gem5/src/cpu/o3/decode_impl.hh

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/*
* Copyright (c) 2004-2006 The Regents of The University of Michigan
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met: redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer;
* redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution;
* neither the name of the copyright holders nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* Authors: Kevin Lim
*/
#include "config/the_isa.hh"
shuffle files around for new directory structure --HG-- rename : cpu/base_cpu.cc => cpu/base.cc rename : cpu/base_cpu.hh => cpu/base.hh rename : cpu/beta_cpu/2bit_local_pred.cc => cpu/o3/2bit_local_pred.cc rename : cpu/beta_cpu/2bit_local_pred.hh => cpu/o3/2bit_local_pred.hh rename : cpu/beta_cpu/alpha_full_cpu.cc => cpu/o3/alpha_cpu.cc rename : cpu/beta_cpu/alpha_full_cpu.hh => cpu/o3/alpha_cpu.hh rename : cpu/beta_cpu/alpha_full_cpu_builder.cc => cpu/o3/alpha_cpu_builder.cc rename : cpu/beta_cpu/alpha_full_cpu_impl.hh => cpu/o3/alpha_cpu_impl.hh rename : cpu/beta_cpu/alpha_dyn_inst.cc => cpu/o3/alpha_dyn_inst.cc rename : cpu/beta_cpu/alpha_dyn_inst.hh => cpu/o3/alpha_dyn_inst.hh rename : cpu/beta_cpu/alpha_dyn_inst_impl.hh => cpu/o3/alpha_dyn_inst_impl.hh rename : cpu/beta_cpu/alpha_impl.hh => cpu/o3/alpha_impl.hh rename : cpu/beta_cpu/alpha_params.hh => cpu/o3/alpha_params.hh rename : cpu/beta_cpu/bpred_unit.cc => cpu/o3/bpred_unit.cc rename : cpu/beta_cpu/bpred_unit.hh => cpu/o3/bpred_unit.hh rename : cpu/beta_cpu/bpred_unit_impl.hh => cpu/o3/bpred_unit_impl.hh rename : cpu/beta_cpu/btb.cc => cpu/o3/btb.cc rename : cpu/beta_cpu/btb.hh => cpu/o3/btb.hh rename : cpu/beta_cpu/comm.hh => cpu/o3/comm.hh rename : cpu/beta_cpu/commit.cc => cpu/o3/commit.cc rename : cpu/beta_cpu/commit.hh => cpu/o3/commit.hh rename : cpu/beta_cpu/commit_impl.hh => cpu/o3/commit_impl.hh rename : cpu/beta_cpu/full_cpu.cc => cpu/o3/cpu.cc rename : cpu/beta_cpu/full_cpu.hh => cpu/o3/cpu.hh rename : cpu/beta_cpu/cpu_policy.hh => cpu/o3/cpu_policy.hh rename : cpu/beta_cpu/decode.cc => cpu/o3/decode.cc rename : cpu/beta_cpu/decode.hh => cpu/o3/decode.hh rename : cpu/beta_cpu/decode_impl.hh => cpu/o3/decode_impl.hh rename : cpu/beta_cpu/fetch.cc => cpu/o3/fetch.cc rename : cpu/beta_cpu/fetch.hh => cpu/o3/fetch.hh rename : cpu/beta_cpu/fetch_impl.hh => cpu/o3/fetch_impl.hh rename : cpu/beta_cpu/free_list.cc => cpu/o3/free_list.cc rename : cpu/beta_cpu/free_list.hh => cpu/o3/free_list.hh rename : cpu/beta_cpu/iew.cc => cpu/o3/iew.cc rename : cpu/beta_cpu/iew.hh => cpu/o3/iew.hh rename : cpu/beta_cpu/iew_impl.hh => cpu/o3/iew_impl.hh rename : cpu/beta_cpu/inst_queue.cc => cpu/o3/inst_queue.cc rename : cpu/beta_cpu/inst_queue.hh => cpu/o3/inst_queue.hh rename : cpu/beta_cpu/inst_queue_impl.hh => cpu/o3/inst_queue_impl.hh rename : cpu/beta_cpu/mem_dep_unit.cc => cpu/o3/mem_dep_unit.cc rename : cpu/beta_cpu/mem_dep_unit.hh => cpu/o3/mem_dep_unit.hh rename : cpu/beta_cpu/mem_dep_unit_impl.hh => cpu/o3/mem_dep_unit_impl.hh rename : cpu/beta_cpu/ras.cc => cpu/o3/ras.cc rename : cpu/beta_cpu/ras.hh => cpu/o3/ras.hh rename : cpu/beta_cpu/regfile.hh => cpu/o3/regfile.hh rename : cpu/beta_cpu/rename.cc => cpu/o3/rename.cc rename : cpu/beta_cpu/rename.hh => cpu/o3/rename.hh rename : cpu/beta_cpu/rename_impl.hh => cpu/o3/rename_impl.hh rename : cpu/beta_cpu/rename_map.cc => cpu/o3/rename_map.cc rename : cpu/beta_cpu/rename_map.hh => cpu/o3/rename_map.hh rename : cpu/beta_cpu/rob.cc => cpu/o3/rob.cc rename : cpu/beta_cpu/rob.hh => cpu/o3/rob.hh rename : cpu/beta_cpu/rob_impl.hh => cpu/o3/rob_impl.hh rename : cpu/beta_cpu/sat_counter.cc => cpu/o3/sat_counter.cc rename : cpu/beta_cpu/sat_counter.hh => cpu/o3/sat_counter.hh rename : cpu/beta_cpu/store_set.cc => cpu/o3/store_set.cc rename : cpu/beta_cpu/store_set.hh => cpu/o3/store_set.hh rename : cpu/beta_cpu/tournament_pred.cc => cpu/o3/tournament_pred.cc rename : cpu/beta_cpu/tournament_pred.hh => cpu/o3/tournament_pred.hh rename : cpu/ooo_cpu/ooo_cpu.cc => cpu/ozone/cpu.cc rename : cpu/ooo_cpu/ooo_cpu.hh => cpu/ozone/cpu.hh rename : cpu/ooo_cpu/ooo_impl.hh => cpu/ozone/cpu_impl.hh rename : cpu/ooo_cpu/ea_list.cc => cpu/ozone/ea_list.cc rename : cpu/ooo_cpu/ea_list.hh => cpu/ozone/ea_list.hh rename : cpu/simple_cpu/simple_cpu.cc => cpu/simple/cpu.cc rename : cpu/simple_cpu/simple_cpu.hh => cpu/simple/cpu.hh rename : cpu/full_cpu/smt.hh => cpu/smt.hh rename : cpu/full_cpu/op_class.hh => encumbered/cpu/full/op_class.hh extra : convert_revision : c4a891d8d6d3e0e9e5ea56be47d851da44d8c032
2005-06-05 02:50:10 +02:00
#include "cpu/o3/decode.hh"
#include "params/DerivO3CPU.hh"
using namespace std;
template<class Impl>
DefaultDecode<Impl>::DefaultDecode(O3CPU *_cpu, DerivO3CPUParams *params)
: cpu(_cpu),
renameToDecodeDelay(params->renameToDecodeDelay),
iewToDecodeDelay(params->iewToDecodeDelay),
commitToDecodeDelay(params->commitToDecodeDelay),
fetchToDecodeDelay(params->fetchToDecodeDelay),
decodeWidth(params->decodeWidth),
numThreads(params->numThreads)
{
_status = Inactive;
// Setup status, make sure stall signals are clear.
for (ThreadID tid = 0; tid < numThreads; ++tid) {
decodeStatus[tid] = Idle;
stalls[tid].rename = false;
stalls[tid].iew = false;
stalls[tid].commit = false;
}
// @todo: Make into a parameter
skidBufferMax = (fetchToDecodeDelay * params->fetchWidth) + decodeWidth;
}
template <class Impl>
std::string
DefaultDecode<Impl>::name() const
{
return cpu->name() + ".decode";
}
Check in of various updates to the CPU. Mainly adds in stats, improves branch prediction, and makes memory dependence work properly. SConscript: Added return address stack, tournament predictor. cpu/base_cpu.cc: Added debug break and print statements. cpu/base_dyn_inst.cc: cpu/base_dyn_inst.hh: Comment out possibly unneeded variables. cpu/beta_cpu/2bit_local_pred.cc: 2bit predictor no longer speculatively updates itself. cpu/beta_cpu/alpha_dyn_inst.hh: Comment formatting. cpu/beta_cpu/alpha_full_cpu.hh: Formatting cpu/beta_cpu/alpha_full_cpu_builder.cc: Added new parameters for branch predictors, and IQ parameters. cpu/beta_cpu/alpha_full_cpu_impl.hh: Register stats. cpu/beta_cpu/alpha_params.hh: Added parameters for IQ, branch predictors, and store sets. cpu/beta_cpu/bpred_unit.cc: Removed one class. cpu/beta_cpu/bpred_unit.hh: Add in RAS, stats. Changed branch predictor unit functionality so that it holds a history of past branches so it can update, and also hold a proper history of the RAS so it can be restored on branch mispredicts. cpu/beta_cpu/bpred_unit_impl.hh: Added in stats, history of branches, RAS. Now bpred unit actually modifies the instruction's predicted next PC. cpu/beta_cpu/btb.cc: Add in sanity checks. cpu/beta_cpu/comm.hh: Add in communication where needed, remove it where it's not. cpu/beta_cpu/commit.hh: cpu/beta_cpu/rename.hh: cpu/beta_cpu/rename_impl.hh: Add in stats. cpu/beta_cpu/commit_impl.hh: Stats, update what is sent back on branch mispredict. cpu/beta_cpu/cpu_policy.hh: Change the bpred unit being used. cpu/beta_cpu/decode.hh: cpu/beta_cpu/decode_impl.hh: Stats. cpu/beta_cpu/fetch.hh: Stats, change squash so it can handle squashes from decode differently than squashes from commit. cpu/beta_cpu/fetch_impl.hh: Add in stats. Change how a cache line is fetched. Update to work with caches. Also have separate functions for different behavior if squash is coming from decode vs commit. cpu/beta_cpu/free_list.hh: Remove some old comments. cpu/beta_cpu/full_cpu.cc: cpu/beta_cpu/full_cpu.hh: Added function to remove instructions from back of instruction list until a certain sequence number. cpu/beta_cpu/iew.hh: Stats, separate squashing behavior due to branches vs memory. cpu/beta_cpu/iew_impl.hh: Stats, separate squashing behavior for branches vs memory. cpu/beta_cpu/inst_queue.cc: Debug stuff cpu/beta_cpu/inst_queue.hh: Stats, change how mem dep unit works, debug stuff cpu/beta_cpu/inst_queue_impl.hh: Stats, change how mem dep unit works, debug stuff. Also add in parameters that used to be hardcoded. cpu/beta_cpu/mem_dep_unit.hh: cpu/beta_cpu/mem_dep_unit_impl.hh: Add in stats, change how memory dependence unit works. It now holds the memory instructions that are waiting for their memory dependences to resolve. It provides which instructions are ready directly to the IQ. cpu/beta_cpu/regfile.hh: Fix up sanity checks. cpu/beta_cpu/rename_map.cc: Fix loop variable type. cpu/beta_cpu/rob_impl.hh: Remove intermediate DynInstPtr cpu/beta_cpu/store_set.cc: Add in debugging statements. cpu/beta_cpu/store_set.hh: Reorder function arguments to match the rest of the calls. --HG-- extra : convert_revision : aabf9b1fecd1d743265dfc3b174d6159937c6f44
2004-10-22 00:02:36 +02:00
template <class Impl>
void
DefaultDecode<Impl>::regStats()
Check in of various updates to the CPU. Mainly adds in stats, improves branch prediction, and makes memory dependence work properly. SConscript: Added return address stack, tournament predictor. cpu/base_cpu.cc: Added debug break and print statements. cpu/base_dyn_inst.cc: cpu/base_dyn_inst.hh: Comment out possibly unneeded variables. cpu/beta_cpu/2bit_local_pred.cc: 2bit predictor no longer speculatively updates itself. cpu/beta_cpu/alpha_dyn_inst.hh: Comment formatting. cpu/beta_cpu/alpha_full_cpu.hh: Formatting cpu/beta_cpu/alpha_full_cpu_builder.cc: Added new parameters for branch predictors, and IQ parameters. cpu/beta_cpu/alpha_full_cpu_impl.hh: Register stats. cpu/beta_cpu/alpha_params.hh: Added parameters for IQ, branch predictors, and store sets. cpu/beta_cpu/bpred_unit.cc: Removed one class. cpu/beta_cpu/bpred_unit.hh: Add in RAS, stats. Changed branch predictor unit functionality so that it holds a history of past branches so it can update, and also hold a proper history of the RAS so it can be restored on branch mispredicts. cpu/beta_cpu/bpred_unit_impl.hh: Added in stats, history of branches, RAS. Now bpred unit actually modifies the instruction's predicted next PC. cpu/beta_cpu/btb.cc: Add in sanity checks. cpu/beta_cpu/comm.hh: Add in communication where needed, remove it where it's not. cpu/beta_cpu/commit.hh: cpu/beta_cpu/rename.hh: cpu/beta_cpu/rename_impl.hh: Add in stats. cpu/beta_cpu/commit_impl.hh: Stats, update what is sent back on branch mispredict. cpu/beta_cpu/cpu_policy.hh: Change the bpred unit being used. cpu/beta_cpu/decode.hh: cpu/beta_cpu/decode_impl.hh: Stats. cpu/beta_cpu/fetch.hh: Stats, change squash so it can handle squashes from decode differently than squashes from commit. cpu/beta_cpu/fetch_impl.hh: Add in stats. Change how a cache line is fetched. Update to work with caches. Also have separate functions for different behavior if squash is coming from decode vs commit. cpu/beta_cpu/free_list.hh: Remove some old comments. cpu/beta_cpu/full_cpu.cc: cpu/beta_cpu/full_cpu.hh: Added function to remove instructions from back of instruction list until a certain sequence number. cpu/beta_cpu/iew.hh: Stats, separate squashing behavior due to branches vs memory. cpu/beta_cpu/iew_impl.hh: Stats, separate squashing behavior for branches vs memory. cpu/beta_cpu/inst_queue.cc: Debug stuff cpu/beta_cpu/inst_queue.hh: Stats, change how mem dep unit works, debug stuff cpu/beta_cpu/inst_queue_impl.hh: Stats, change how mem dep unit works, debug stuff. Also add in parameters that used to be hardcoded. cpu/beta_cpu/mem_dep_unit.hh: cpu/beta_cpu/mem_dep_unit_impl.hh: Add in stats, change how memory dependence unit works. It now holds the memory instructions that are waiting for their memory dependences to resolve. It provides which instructions are ready directly to the IQ. cpu/beta_cpu/regfile.hh: Fix up sanity checks. cpu/beta_cpu/rename_map.cc: Fix loop variable type. cpu/beta_cpu/rob_impl.hh: Remove intermediate DynInstPtr cpu/beta_cpu/store_set.cc: Add in debugging statements. cpu/beta_cpu/store_set.hh: Reorder function arguments to match the rest of the calls. --HG-- extra : convert_revision : aabf9b1fecd1d743265dfc3b174d6159937c6f44
2004-10-22 00:02:36 +02:00
{
decodeIdleCycles
.name(name() + ".DECODE:IdleCycles")
Check in of various updates to the CPU. Mainly adds in stats, improves branch prediction, and makes memory dependence work properly. SConscript: Added return address stack, tournament predictor. cpu/base_cpu.cc: Added debug break and print statements. cpu/base_dyn_inst.cc: cpu/base_dyn_inst.hh: Comment out possibly unneeded variables. cpu/beta_cpu/2bit_local_pred.cc: 2bit predictor no longer speculatively updates itself. cpu/beta_cpu/alpha_dyn_inst.hh: Comment formatting. cpu/beta_cpu/alpha_full_cpu.hh: Formatting cpu/beta_cpu/alpha_full_cpu_builder.cc: Added new parameters for branch predictors, and IQ parameters. cpu/beta_cpu/alpha_full_cpu_impl.hh: Register stats. cpu/beta_cpu/alpha_params.hh: Added parameters for IQ, branch predictors, and store sets. cpu/beta_cpu/bpred_unit.cc: Removed one class. cpu/beta_cpu/bpred_unit.hh: Add in RAS, stats. Changed branch predictor unit functionality so that it holds a history of past branches so it can update, and also hold a proper history of the RAS so it can be restored on branch mispredicts. cpu/beta_cpu/bpred_unit_impl.hh: Added in stats, history of branches, RAS. Now bpred unit actually modifies the instruction's predicted next PC. cpu/beta_cpu/btb.cc: Add in sanity checks. cpu/beta_cpu/comm.hh: Add in communication where needed, remove it where it's not. cpu/beta_cpu/commit.hh: cpu/beta_cpu/rename.hh: cpu/beta_cpu/rename_impl.hh: Add in stats. cpu/beta_cpu/commit_impl.hh: Stats, update what is sent back on branch mispredict. cpu/beta_cpu/cpu_policy.hh: Change the bpred unit being used. cpu/beta_cpu/decode.hh: cpu/beta_cpu/decode_impl.hh: Stats. cpu/beta_cpu/fetch.hh: Stats, change squash so it can handle squashes from decode differently than squashes from commit. cpu/beta_cpu/fetch_impl.hh: Add in stats. Change how a cache line is fetched. Update to work with caches. Also have separate functions for different behavior if squash is coming from decode vs commit. cpu/beta_cpu/free_list.hh: Remove some old comments. cpu/beta_cpu/full_cpu.cc: cpu/beta_cpu/full_cpu.hh: Added function to remove instructions from back of instruction list until a certain sequence number. cpu/beta_cpu/iew.hh: Stats, separate squashing behavior due to branches vs memory. cpu/beta_cpu/iew_impl.hh: Stats, separate squashing behavior for branches vs memory. cpu/beta_cpu/inst_queue.cc: Debug stuff cpu/beta_cpu/inst_queue.hh: Stats, change how mem dep unit works, debug stuff cpu/beta_cpu/inst_queue_impl.hh: Stats, change how mem dep unit works, debug stuff. Also add in parameters that used to be hardcoded. cpu/beta_cpu/mem_dep_unit.hh: cpu/beta_cpu/mem_dep_unit_impl.hh: Add in stats, change how memory dependence unit works. It now holds the memory instructions that are waiting for their memory dependences to resolve. It provides which instructions are ready directly to the IQ. cpu/beta_cpu/regfile.hh: Fix up sanity checks. cpu/beta_cpu/rename_map.cc: Fix loop variable type. cpu/beta_cpu/rob_impl.hh: Remove intermediate DynInstPtr cpu/beta_cpu/store_set.cc: Add in debugging statements. cpu/beta_cpu/store_set.hh: Reorder function arguments to match the rest of the calls. --HG-- extra : convert_revision : aabf9b1fecd1d743265dfc3b174d6159937c6f44
2004-10-22 00:02:36 +02:00
.desc("Number of cycles decode is idle")
.prereq(decodeIdleCycles);
decodeBlockedCycles
.name(name() + ".DECODE:BlockedCycles")
Check in of various updates to the CPU. Mainly adds in stats, improves branch prediction, and makes memory dependence work properly. SConscript: Added return address stack, tournament predictor. cpu/base_cpu.cc: Added debug break and print statements. cpu/base_dyn_inst.cc: cpu/base_dyn_inst.hh: Comment out possibly unneeded variables. cpu/beta_cpu/2bit_local_pred.cc: 2bit predictor no longer speculatively updates itself. cpu/beta_cpu/alpha_dyn_inst.hh: Comment formatting. cpu/beta_cpu/alpha_full_cpu.hh: Formatting cpu/beta_cpu/alpha_full_cpu_builder.cc: Added new parameters for branch predictors, and IQ parameters. cpu/beta_cpu/alpha_full_cpu_impl.hh: Register stats. cpu/beta_cpu/alpha_params.hh: Added parameters for IQ, branch predictors, and store sets. cpu/beta_cpu/bpred_unit.cc: Removed one class. cpu/beta_cpu/bpred_unit.hh: Add in RAS, stats. Changed branch predictor unit functionality so that it holds a history of past branches so it can update, and also hold a proper history of the RAS so it can be restored on branch mispredicts. cpu/beta_cpu/bpred_unit_impl.hh: Added in stats, history of branches, RAS. Now bpred unit actually modifies the instruction's predicted next PC. cpu/beta_cpu/btb.cc: Add in sanity checks. cpu/beta_cpu/comm.hh: Add in communication where needed, remove it where it's not. cpu/beta_cpu/commit.hh: cpu/beta_cpu/rename.hh: cpu/beta_cpu/rename_impl.hh: Add in stats. cpu/beta_cpu/commit_impl.hh: Stats, update what is sent back on branch mispredict. cpu/beta_cpu/cpu_policy.hh: Change the bpred unit being used. cpu/beta_cpu/decode.hh: cpu/beta_cpu/decode_impl.hh: Stats. cpu/beta_cpu/fetch.hh: Stats, change squash so it can handle squashes from decode differently than squashes from commit. cpu/beta_cpu/fetch_impl.hh: Add in stats. Change how a cache line is fetched. Update to work with caches. Also have separate functions for different behavior if squash is coming from decode vs commit. cpu/beta_cpu/free_list.hh: Remove some old comments. cpu/beta_cpu/full_cpu.cc: cpu/beta_cpu/full_cpu.hh: Added function to remove instructions from back of instruction list until a certain sequence number. cpu/beta_cpu/iew.hh: Stats, separate squashing behavior due to branches vs memory. cpu/beta_cpu/iew_impl.hh: Stats, separate squashing behavior for branches vs memory. cpu/beta_cpu/inst_queue.cc: Debug stuff cpu/beta_cpu/inst_queue.hh: Stats, change how mem dep unit works, debug stuff cpu/beta_cpu/inst_queue_impl.hh: Stats, change how mem dep unit works, debug stuff. Also add in parameters that used to be hardcoded. cpu/beta_cpu/mem_dep_unit.hh: cpu/beta_cpu/mem_dep_unit_impl.hh: Add in stats, change how memory dependence unit works. It now holds the memory instructions that are waiting for their memory dependences to resolve. It provides which instructions are ready directly to the IQ. cpu/beta_cpu/regfile.hh: Fix up sanity checks. cpu/beta_cpu/rename_map.cc: Fix loop variable type. cpu/beta_cpu/rob_impl.hh: Remove intermediate DynInstPtr cpu/beta_cpu/store_set.cc: Add in debugging statements. cpu/beta_cpu/store_set.hh: Reorder function arguments to match the rest of the calls. --HG-- extra : convert_revision : aabf9b1fecd1d743265dfc3b174d6159937c6f44
2004-10-22 00:02:36 +02:00
.desc("Number of cycles decode is blocked")
.prereq(decodeBlockedCycles);
decodeRunCycles
.name(name() + ".DECODE:RunCycles")
.desc("Number of cycles decode is running")
.prereq(decodeRunCycles);
Check in of various updates to the CPU. Mainly adds in stats, improves branch prediction, and makes memory dependence work properly. SConscript: Added return address stack, tournament predictor. cpu/base_cpu.cc: Added debug break and print statements. cpu/base_dyn_inst.cc: cpu/base_dyn_inst.hh: Comment out possibly unneeded variables. cpu/beta_cpu/2bit_local_pred.cc: 2bit predictor no longer speculatively updates itself. cpu/beta_cpu/alpha_dyn_inst.hh: Comment formatting. cpu/beta_cpu/alpha_full_cpu.hh: Formatting cpu/beta_cpu/alpha_full_cpu_builder.cc: Added new parameters for branch predictors, and IQ parameters. cpu/beta_cpu/alpha_full_cpu_impl.hh: Register stats. cpu/beta_cpu/alpha_params.hh: Added parameters for IQ, branch predictors, and store sets. cpu/beta_cpu/bpred_unit.cc: Removed one class. cpu/beta_cpu/bpred_unit.hh: Add in RAS, stats. Changed branch predictor unit functionality so that it holds a history of past branches so it can update, and also hold a proper history of the RAS so it can be restored on branch mispredicts. cpu/beta_cpu/bpred_unit_impl.hh: Added in stats, history of branches, RAS. Now bpred unit actually modifies the instruction's predicted next PC. cpu/beta_cpu/btb.cc: Add in sanity checks. cpu/beta_cpu/comm.hh: Add in communication where needed, remove it where it's not. cpu/beta_cpu/commit.hh: cpu/beta_cpu/rename.hh: cpu/beta_cpu/rename_impl.hh: Add in stats. cpu/beta_cpu/commit_impl.hh: Stats, update what is sent back on branch mispredict. cpu/beta_cpu/cpu_policy.hh: Change the bpred unit being used. cpu/beta_cpu/decode.hh: cpu/beta_cpu/decode_impl.hh: Stats. cpu/beta_cpu/fetch.hh: Stats, change squash so it can handle squashes from decode differently than squashes from commit. cpu/beta_cpu/fetch_impl.hh: Add in stats. Change how a cache line is fetched. Update to work with caches. Also have separate functions for different behavior if squash is coming from decode vs commit. cpu/beta_cpu/free_list.hh: Remove some old comments. cpu/beta_cpu/full_cpu.cc: cpu/beta_cpu/full_cpu.hh: Added function to remove instructions from back of instruction list until a certain sequence number. cpu/beta_cpu/iew.hh: Stats, separate squashing behavior due to branches vs memory. cpu/beta_cpu/iew_impl.hh: Stats, separate squashing behavior for branches vs memory. cpu/beta_cpu/inst_queue.cc: Debug stuff cpu/beta_cpu/inst_queue.hh: Stats, change how mem dep unit works, debug stuff cpu/beta_cpu/inst_queue_impl.hh: Stats, change how mem dep unit works, debug stuff. Also add in parameters that used to be hardcoded. cpu/beta_cpu/mem_dep_unit.hh: cpu/beta_cpu/mem_dep_unit_impl.hh: Add in stats, change how memory dependence unit works. It now holds the memory instructions that are waiting for their memory dependences to resolve. It provides which instructions are ready directly to the IQ. cpu/beta_cpu/regfile.hh: Fix up sanity checks. cpu/beta_cpu/rename_map.cc: Fix loop variable type. cpu/beta_cpu/rob_impl.hh: Remove intermediate DynInstPtr cpu/beta_cpu/store_set.cc: Add in debugging statements. cpu/beta_cpu/store_set.hh: Reorder function arguments to match the rest of the calls. --HG-- extra : convert_revision : aabf9b1fecd1d743265dfc3b174d6159937c6f44
2004-10-22 00:02:36 +02:00
decodeUnblockCycles
.name(name() + ".DECODE:UnblockCycles")
Check in of various updates to the CPU. Mainly adds in stats, improves branch prediction, and makes memory dependence work properly. SConscript: Added return address stack, tournament predictor. cpu/base_cpu.cc: Added debug break and print statements. cpu/base_dyn_inst.cc: cpu/base_dyn_inst.hh: Comment out possibly unneeded variables. cpu/beta_cpu/2bit_local_pred.cc: 2bit predictor no longer speculatively updates itself. cpu/beta_cpu/alpha_dyn_inst.hh: Comment formatting. cpu/beta_cpu/alpha_full_cpu.hh: Formatting cpu/beta_cpu/alpha_full_cpu_builder.cc: Added new parameters for branch predictors, and IQ parameters. cpu/beta_cpu/alpha_full_cpu_impl.hh: Register stats. cpu/beta_cpu/alpha_params.hh: Added parameters for IQ, branch predictors, and store sets. cpu/beta_cpu/bpred_unit.cc: Removed one class. cpu/beta_cpu/bpred_unit.hh: Add in RAS, stats. Changed branch predictor unit functionality so that it holds a history of past branches so it can update, and also hold a proper history of the RAS so it can be restored on branch mispredicts. cpu/beta_cpu/bpred_unit_impl.hh: Added in stats, history of branches, RAS. Now bpred unit actually modifies the instruction's predicted next PC. cpu/beta_cpu/btb.cc: Add in sanity checks. cpu/beta_cpu/comm.hh: Add in communication where needed, remove it where it's not. cpu/beta_cpu/commit.hh: cpu/beta_cpu/rename.hh: cpu/beta_cpu/rename_impl.hh: Add in stats. cpu/beta_cpu/commit_impl.hh: Stats, update what is sent back on branch mispredict. cpu/beta_cpu/cpu_policy.hh: Change the bpred unit being used. cpu/beta_cpu/decode.hh: cpu/beta_cpu/decode_impl.hh: Stats. cpu/beta_cpu/fetch.hh: Stats, change squash so it can handle squashes from decode differently than squashes from commit. cpu/beta_cpu/fetch_impl.hh: Add in stats. Change how a cache line is fetched. Update to work with caches. Also have separate functions for different behavior if squash is coming from decode vs commit. cpu/beta_cpu/free_list.hh: Remove some old comments. cpu/beta_cpu/full_cpu.cc: cpu/beta_cpu/full_cpu.hh: Added function to remove instructions from back of instruction list until a certain sequence number. cpu/beta_cpu/iew.hh: Stats, separate squashing behavior due to branches vs memory. cpu/beta_cpu/iew_impl.hh: Stats, separate squashing behavior for branches vs memory. cpu/beta_cpu/inst_queue.cc: Debug stuff cpu/beta_cpu/inst_queue.hh: Stats, change how mem dep unit works, debug stuff cpu/beta_cpu/inst_queue_impl.hh: Stats, change how mem dep unit works, debug stuff. Also add in parameters that used to be hardcoded. cpu/beta_cpu/mem_dep_unit.hh: cpu/beta_cpu/mem_dep_unit_impl.hh: Add in stats, change how memory dependence unit works. It now holds the memory instructions that are waiting for their memory dependences to resolve. It provides which instructions are ready directly to the IQ. cpu/beta_cpu/regfile.hh: Fix up sanity checks. cpu/beta_cpu/rename_map.cc: Fix loop variable type. cpu/beta_cpu/rob_impl.hh: Remove intermediate DynInstPtr cpu/beta_cpu/store_set.cc: Add in debugging statements. cpu/beta_cpu/store_set.hh: Reorder function arguments to match the rest of the calls. --HG-- extra : convert_revision : aabf9b1fecd1d743265dfc3b174d6159937c6f44
2004-10-22 00:02:36 +02:00
.desc("Number of cycles decode is unblocking")
.prereq(decodeUnblockCycles);
decodeSquashCycles
.name(name() + ".DECODE:SquashCycles")
Check in of various updates to the CPU. Mainly adds in stats, improves branch prediction, and makes memory dependence work properly. SConscript: Added return address stack, tournament predictor. cpu/base_cpu.cc: Added debug break and print statements. cpu/base_dyn_inst.cc: cpu/base_dyn_inst.hh: Comment out possibly unneeded variables. cpu/beta_cpu/2bit_local_pred.cc: 2bit predictor no longer speculatively updates itself. cpu/beta_cpu/alpha_dyn_inst.hh: Comment formatting. cpu/beta_cpu/alpha_full_cpu.hh: Formatting cpu/beta_cpu/alpha_full_cpu_builder.cc: Added new parameters for branch predictors, and IQ parameters. cpu/beta_cpu/alpha_full_cpu_impl.hh: Register stats. cpu/beta_cpu/alpha_params.hh: Added parameters for IQ, branch predictors, and store sets. cpu/beta_cpu/bpred_unit.cc: Removed one class. cpu/beta_cpu/bpred_unit.hh: Add in RAS, stats. Changed branch predictor unit functionality so that it holds a history of past branches so it can update, and also hold a proper history of the RAS so it can be restored on branch mispredicts. cpu/beta_cpu/bpred_unit_impl.hh: Added in stats, history of branches, RAS. Now bpred unit actually modifies the instruction's predicted next PC. cpu/beta_cpu/btb.cc: Add in sanity checks. cpu/beta_cpu/comm.hh: Add in communication where needed, remove it where it's not. cpu/beta_cpu/commit.hh: cpu/beta_cpu/rename.hh: cpu/beta_cpu/rename_impl.hh: Add in stats. cpu/beta_cpu/commit_impl.hh: Stats, update what is sent back on branch mispredict. cpu/beta_cpu/cpu_policy.hh: Change the bpred unit being used. cpu/beta_cpu/decode.hh: cpu/beta_cpu/decode_impl.hh: Stats. cpu/beta_cpu/fetch.hh: Stats, change squash so it can handle squashes from decode differently than squashes from commit. cpu/beta_cpu/fetch_impl.hh: Add in stats. Change how a cache line is fetched. Update to work with caches. Also have separate functions for different behavior if squash is coming from decode vs commit. cpu/beta_cpu/free_list.hh: Remove some old comments. cpu/beta_cpu/full_cpu.cc: cpu/beta_cpu/full_cpu.hh: Added function to remove instructions from back of instruction list until a certain sequence number. cpu/beta_cpu/iew.hh: Stats, separate squashing behavior due to branches vs memory. cpu/beta_cpu/iew_impl.hh: Stats, separate squashing behavior for branches vs memory. cpu/beta_cpu/inst_queue.cc: Debug stuff cpu/beta_cpu/inst_queue.hh: Stats, change how mem dep unit works, debug stuff cpu/beta_cpu/inst_queue_impl.hh: Stats, change how mem dep unit works, debug stuff. Also add in parameters that used to be hardcoded. cpu/beta_cpu/mem_dep_unit.hh: cpu/beta_cpu/mem_dep_unit_impl.hh: Add in stats, change how memory dependence unit works. It now holds the memory instructions that are waiting for their memory dependences to resolve. It provides which instructions are ready directly to the IQ. cpu/beta_cpu/regfile.hh: Fix up sanity checks. cpu/beta_cpu/rename_map.cc: Fix loop variable type. cpu/beta_cpu/rob_impl.hh: Remove intermediate DynInstPtr cpu/beta_cpu/store_set.cc: Add in debugging statements. cpu/beta_cpu/store_set.hh: Reorder function arguments to match the rest of the calls. --HG-- extra : convert_revision : aabf9b1fecd1d743265dfc3b174d6159937c6f44
2004-10-22 00:02:36 +02:00
.desc("Number of cycles decode is squashing")
.prereq(decodeSquashCycles);
decodeBranchResolved
.name(name() + ".DECODE:BranchResolved")
.desc("Number of times decode resolved a branch")
.prereq(decodeBranchResolved);
Check in of various updates to the CPU. Mainly adds in stats, improves branch prediction, and makes memory dependence work properly. SConscript: Added return address stack, tournament predictor. cpu/base_cpu.cc: Added debug break and print statements. cpu/base_dyn_inst.cc: cpu/base_dyn_inst.hh: Comment out possibly unneeded variables. cpu/beta_cpu/2bit_local_pred.cc: 2bit predictor no longer speculatively updates itself. cpu/beta_cpu/alpha_dyn_inst.hh: Comment formatting. cpu/beta_cpu/alpha_full_cpu.hh: Formatting cpu/beta_cpu/alpha_full_cpu_builder.cc: Added new parameters for branch predictors, and IQ parameters. cpu/beta_cpu/alpha_full_cpu_impl.hh: Register stats. cpu/beta_cpu/alpha_params.hh: Added parameters for IQ, branch predictors, and store sets. cpu/beta_cpu/bpred_unit.cc: Removed one class. cpu/beta_cpu/bpred_unit.hh: Add in RAS, stats. Changed branch predictor unit functionality so that it holds a history of past branches so it can update, and also hold a proper history of the RAS so it can be restored on branch mispredicts. cpu/beta_cpu/bpred_unit_impl.hh: Added in stats, history of branches, RAS. Now bpred unit actually modifies the instruction's predicted next PC. cpu/beta_cpu/btb.cc: Add in sanity checks. cpu/beta_cpu/comm.hh: Add in communication where needed, remove it where it's not. cpu/beta_cpu/commit.hh: cpu/beta_cpu/rename.hh: cpu/beta_cpu/rename_impl.hh: Add in stats. cpu/beta_cpu/commit_impl.hh: Stats, update what is sent back on branch mispredict. cpu/beta_cpu/cpu_policy.hh: Change the bpred unit being used. cpu/beta_cpu/decode.hh: cpu/beta_cpu/decode_impl.hh: Stats. cpu/beta_cpu/fetch.hh: Stats, change squash so it can handle squashes from decode differently than squashes from commit. cpu/beta_cpu/fetch_impl.hh: Add in stats. Change how a cache line is fetched. Update to work with caches. Also have separate functions for different behavior if squash is coming from decode vs commit. cpu/beta_cpu/free_list.hh: Remove some old comments. cpu/beta_cpu/full_cpu.cc: cpu/beta_cpu/full_cpu.hh: Added function to remove instructions from back of instruction list until a certain sequence number. cpu/beta_cpu/iew.hh: Stats, separate squashing behavior due to branches vs memory. cpu/beta_cpu/iew_impl.hh: Stats, separate squashing behavior for branches vs memory. cpu/beta_cpu/inst_queue.cc: Debug stuff cpu/beta_cpu/inst_queue.hh: Stats, change how mem dep unit works, debug stuff cpu/beta_cpu/inst_queue_impl.hh: Stats, change how mem dep unit works, debug stuff. Also add in parameters that used to be hardcoded. cpu/beta_cpu/mem_dep_unit.hh: cpu/beta_cpu/mem_dep_unit_impl.hh: Add in stats, change how memory dependence unit works. It now holds the memory instructions that are waiting for their memory dependences to resolve. It provides which instructions are ready directly to the IQ. cpu/beta_cpu/regfile.hh: Fix up sanity checks. cpu/beta_cpu/rename_map.cc: Fix loop variable type. cpu/beta_cpu/rob_impl.hh: Remove intermediate DynInstPtr cpu/beta_cpu/store_set.cc: Add in debugging statements. cpu/beta_cpu/store_set.hh: Reorder function arguments to match the rest of the calls. --HG-- extra : convert_revision : aabf9b1fecd1d743265dfc3b174d6159937c6f44
2004-10-22 00:02:36 +02:00
decodeBranchMispred
.name(name() + ".DECODE:BranchMispred")
Check in of various updates to the CPU. Mainly adds in stats, improves branch prediction, and makes memory dependence work properly. SConscript: Added return address stack, tournament predictor. cpu/base_cpu.cc: Added debug break and print statements. cpu/base_dyn_inst.cc: cpu/base_dyn_inst.hh: Comment out possibly unneeded variables. cpu/beta_cpu/2bit_local_pred.cc: 2bit predictor no longer speculatively updates itself. cpu/beta_cpu/alpha_dyn_inst.hh: Comment formatting. cpu/beta_cpu/alpha_full_cpu.hh: Formatting cpu/beta_cpu/alpha_full_cpu_builder.cc: Added new parameters for branch predictors, and IQ parameters. cpu/beta_cpu/alpha_full_cpu_impl.hh: Register stats. cpu/beta_cpu/alpha_params.hh: Added parameters for IQ, branch predictors, and store sets. cpu/beta_cpu/bpred_unit.cc: Removed one class. cpu/beta_cpu/bpred_unit.hh: Add in RAS, stats. Changed branch predictor unit functionality so that it holds a history of past branches so it can update, and also hold a proper history of the RAS so it can be restored on branch mispredicts. cpu/beta_cpu/bpred_unit_impl.hh: Added in stats, history of branches, RAS. Now bpred unit actually modifies the instruction's predicted next PC. cpu/beta_cpu/btb.cc: Add in sanity checks. cpu/beta_cpu/comm.hh: Add in communication where needed, remove it where it's not. cpu/beta_cpu/commit.hh: cpu/beta_cpu/rename.hh: cpu/beta_cpu/rename_impl.hh: Add in stats. cpu/beta_cpu/commit_impl.hh: Stats, update what is sent back on branch mispredict. cpu/beta_cpu/cpu_policy.hh: Change the bpred unit being used. cpu/beta_cpu/decode.hh: cpu/beta_cpu/decode_impl.hh: Stats. cpu/beta_cpu/fetch.hh: Stats, change squash so it can handle squashes from decode differently than squashes from commit. cpu/beta_cpu/fetch_impl.hh: Add in stats. Change how a cache line is fetched. Update to work with caches. Also have separate functions for different behavior if squash is coming from decode vs commit. cpu/beta_cpu/free_list.hh: Remove some old comments. cpu/beta_cpu/full_cpu.cc: cpu/beta_cpu/full_cpu.hh: Added function to remove instructions from back of instruction list until a certain sequence number. cpu/beta_cpu/iew.hh: Stats, separate squashing behavior due to branches vs memory. cpu/beta_cpu/iew_impl.hh: Stats, separate squashing behavior for branches vs memory. cpu/beta_cpu/inst_queue.cc: Debug stuff cpu/beta_cpu/inst_queue.hh: Stats, change how mem dep unit works, debug stuff cpu/beta_cpu/inst_queue_impl.hh: Stats, change how mem dep unit works, debug stuff. Also add in parameters that used to be hardcoded. cpu/beta_cpu/mem_dep_unit.hh: cpu/beta_cpu/mem_dep_unit_impl.hh: Add in stats, change how memory dependence unit works. It now holds the memory instructions that are waiting for their memory dependences to resolve. It provides which instructions are ready directly to the IQ. cpu/beta_cpu/regfile.hh: Fix up sanity checks. cpu/beta_cpu/rename_map.cc: Fix loop variable type. cpu/beta_cpu/rob_impl.hh: Remove intermediate DynInstPtr cpu/beta_cpu/store_set.cc: Add in debugging statements. cpu/beta_cpu/store_set.hh: Reorder function arguments to match the rest of the calls. --HG-- extra : convert_revision : aabf9b1fecd1d743265dfc3b174d6159937c6f44
2004-10-22 00:02:36 +02:00
.desc("Number of times decode detected a branch misprediction")
.prereq(decodeBranchMispred);
decodeControlMispred
.name(name() + ".DECODE:ControlMispred")
Check in of various updates to the CPU. Mainly adds in stats, improves branch prediction, and makes memory dependence work properly. SConscript: Added return address stack, tournament predictor. cpu/base_cpu.cc: Added debug break and print statements. cpu/base_dyn_inst.cc: cpu/base_dyn_inst.hh: Comment out possibly unneeded variables. cpu/beta_cpu/2bit_local_pred.cc: 2bit predictor no longer speculatively updates itself. cpu/beta_cpu/alpha_dyn_inst.hh: Comment formatting. cpu/beta_cpu/alpha_full_cpu.hh: Formatting cpu/beta_cpu/alpha_full_cpu_builder.cc: Added new parameters for branch predictors, and IQ parameters. cpu/beta_cpu/alpha_full_cpu_impl.hh: Register stats. cpu/beta_cpu/alpha_params.hh: Added parameters for IQ, branch predictors, and store sets. cpu/beta_cpu/bpred_unit.cc: Removed one class. cpu/beta_cpu/bpred_unit.hh: Add in RAS, stats. Changed branch predictor unit functionality so that it holds a history of past branches so it can update, and also hold a proper history of the RAS so it can be restored on branch mispredicts. cpu/beta_cpu/bpred_unit_impl.hh: Added in stats, history of branches, RAS. Now bpred unit actually modifies the instruction's predicted next PC. cpu/beta_cpu/btb.cc: Add in sanity checks. cpu/beta_cpu/comm.hh: Add in communication where needed, remove it where it's not. cpu/beta_cpu/commit.hh: cpu/beta_cpu/rename.hh: cpu/beta_cpu/rename_impl.hh: Add in stats. cpu/beta_cpu/commit_impl.hh: Stats, update what is sent back on branch mispredict. cpu/beta_cpu/cpu_policy.hh: Change the bpred unit being used. cpu/beta_cpu/decode.hh: cpu/beta_cpu/decode_impl.hh: Stats. cpu/beta_cpu/fetch.hh: Stats, change squash so it can handle squashes from decode differently than squashes from commit. cpu/beta_cpu/fetch_impl.hh: Add in stats. Change how a cache line is fetched. Update to work with caches. Also have separate functions for different behavior if squash is coming from decode vs commit. cpu/beta_cpu/free_list.hh: Remove some old comments. cpu/beta_cpu/full_cpu.cc: cpu/beta_cpu/full_cpu.hh: Added function to remove instructions from back of instruction list until a certain sequence number. cpu/beta_cpu/iew.hh: Stats, separate squashing behavior due to branches vs memory. cpu/beta_cpu/iew_impl.hh: Stats, separate squashing behavior for branches vs memory. cpu/beta_cpu/inst_queue.cc: Debug stuff cpu/beta_cpu/inst_queue.hh: Stats, change how mem dep unit works, debug stuff cpu/beta_cpu/inst_queue_impl.hh: Stats, change how mem dep unit works, debug stuff. Also add in parameters that used to be hardcoded. cpu/beta_cpu/mem_dep_unit.hh: cpu/beta_cpu/mem_dep_unit_impl.hh: Add in stats, change how memory dependence unit works. It now holds the memory instructions that are waiting for their memory dependences to resolve. It provides which instructions are ready directly to the IQ. cpu/beta_cpu/regfile.hh: Fix up sanity checks. cpu/beta_cpu/rename_map.cc: Fix loop variable type. cpu/beta_cpu/rob_impl.hh: Remove intermediate DynInstPtr cpu/beta_cpu/store_set.cc: Add in debugging statements. cpu/beta_cpu/store_set.hh: Reorder function arguments to match the rest of the calls. --HG-- extra : convert_revision : aabf9b1fecd1d743265dfc3b174d6159937c6f44
2004-10-22 00:02:36 +02:00
.desc("Number of times decode detected an instruction incorrectly"
" predicted as a control")
.prereq(decodeControlMispred);
decodeDecodedInsts
.name(name() + ".DECODE:DecodedInsts")
Check in of various updates to the CPU. Mainly adds in stats, improves branch prediction, and makes memory dependence work properly. SConscript: Added return address stack, tournament predictor. cpu/base_cpu.cc: Added debug break and print statements. cpu/base_dyn_inst.cc: cpu/base_dyn_inst.hh: Comment out possibly unneeded variables. cpu/beta_cpu/2bit_local_pred.cc: 2bit predictor no longer speculatively updates itself. cpu/beta_cpu/alpha_dyn_inst.hh: Comment formatting. cpu/beta_cpu/alpha_full_cpu.hh: Formatting cpu/beta_cpu/alpha_full_cpu_builder.cc: Added new parameters for branch predictors, and IQ parameters. cpu/beta_cpu/alpha_full_cpu_impl.hh: Register stats. cpu/beta_cpu/alpha_params.hh: Added parameters for IQ, branch predictors, and store sets. cpu/beta_cpu/bpred_unit.cc: Removed one class. cpu/beta_cpu/bpred_unit.hh: Add in RAS, stats. Changed branch predictor unit functionality so that it holds a history of past branches so it can update, and also hold a proper history of the RAS so it can be restored on branch mispredicts. cpu/beta_cpu/bpred_unit_impl.hh: Added in stats, history of branches, RAS. Now bpred unit actually modifies the instruction's predicted next PC. cpu/beta_cpu/btb.cc: Add in sanity checks. cpu/beta_cpu/comm.hh: Add in communication where needed, remove it where it's not. cpu/beta_cpu/commit.hh: cpu/beta_cpu/rename.hh: cpu/beta_cpu/rename_impl.hh: Add in stats. cpu/beta_cpu/commit_impl.hh: Stats, update what is sent back on branch mispredict. cpu/beta_cpu/cpu_policy.hh: Change the bpred unit being used. cpu/beta_cpu/decode.hh: cpu/beta_cpu/decode_impl.hh: Stats. cpu/beta_cpu/fetch.hh: Stats, change squash so it can handle squashes from decode differently than squashes from commit. cpu/beta_cpu/fetch_impl.hh: Add in stats. Change how a cache line is fetched. Update to work with caches. Also have separate functions for different behavior if squash is coming from decode vs commit. cpu/beta_cpu/free_list.hh: Remove some old comments. cpu/beta_cpu/full_cpu.cc: cpu/beta_cpu/full_cpu.hh: Added function to remove instructions from back of instruction list until a certain sequence number. cpu/beta_cpu/iew.hh: Stats, separate squashing behavior due to branches vs memory. cpu/beta_cpu/iew_impl.hh: Stats, separate squashing behavior for branches vs memory. cpu/beta_cpu/inst_queue.cc: Debug stuff cpu/beta_cpu/inst_queue.hh: Stats, change how mem dep unit works, debug stuff cpu/beta_cpu/inst_queue_impl.hh: Stats, change how mem dep unit works, debug stuff. Also add in parameters that used to be hardcoded. cpu/beta_cpu/mem_dep_unit.hh: cpu/beta_cpu/mem_dep_unit_impl.hh: Add in stats, change how memory dependence unit works. It now holds the memory instructions that are waiting for their memory dependences to resolve. It provides which instructions are ready directly to the IQ. cpu/beta_cpu/regfile.hh: Fix up sanity checks. cpu/beta_cpu/rename_map.cc: Fix loop variable type. cpu/beta_cpu/rob_impl.hh: Remove intermediate DynInstPtr cpu/beta_cpu/store_set.cc: Add in debugging statements. cpu/beta_cpu/store_set.hh: Reorder function arguments to match the rest of the calls. --HG-- extra : convert_revision : aabf9b1fecd1d743265dfc3b174d6159937c6f44
2004-10-22 00:02:36 +02:00
.desc("Number of instructions handled by decode")
.prereq(decodeDecodedInsts);
decodeSquashedInsts
.name(name() + ".DECODE:SquashedInsts")
Check in of various updates to the CPU. Mainly adds in stats, improves branch prediction, and makes memory dependence work properly. SConscript: Added return address stack, tournament predictor. cpu/base_cpu.cc: Added debug break and print statements. cpu/base_dyn_inst.cc: cpu/base_dyn_inst.hh: Comment out possibly unneeded variables. cpu/beta_cpu/2bit_local_pred.cc: 2bit predictor no longer speculatively updates itself. cpu/beta_cpu/alpha_dyn_inst.hh: Comment formatting. cpu/beta_cpu/alpha_full_cpu.hh: Formatting cpu/beta_cpu/alpha_full_cpu_builder.cc: Added new parameters for branch predictors, and IQ parameters. cpu/beta_cpu/alpha_full_cpu_impl.hh: Register stats. cpu/beta_cpu/alpha_params.hh: Added parameters for IQ, branch predictors, and store sets. cpu/beta_cpu/bpred_unit.cc: Removed one class. cpu/beta_cpu/bpred_unit.hh: Add in RAS, stats. Changed branch predictor unit functionality so that it holds a history of past branches so it can update, and also hold a proper history of the RAS so it can be restored on branch mispredicts. cpu/beta_cpu/bpred_unit_impl.hh: Added in stats, history of branches, RAS. Now bpred unit actually modifies the instruction's predicted next PC. cpu/beta_cpu/btb.cc: Add in sanity checks. cpu/beta_cpu/comm.hh: Add in communication where needed, remove it where it's not. cpu/beta_cpu/commit.hh: cpu/beta_cpu/rename.hh: cpu/beta_cpu/rename_impl.hh: Add in stats. cpu/beta_cpu/commit_impl.hh: Stats, update what is sent back on branch mispredict. cpu/beta_cpu/cpu_policy.hh: Change the bpred unit being used. cpu/beta_cpu/decode.hh: cpu/beta_cpu/decode_impl.hh: Stats. cpu/beta_cpu/fetch.hh: Stats, change squash so it can handle squashes from decode differently than squashes from commit. cpu/beta_cpu/fetch_impl.hh: Add in stats. Change how a cache line is fetched. Update to work with caches. Also have separate functions for different behavior if squash is coming from decode vs commit. cpu/beta_cpu/free_list.hh: Remove some old comments. cpu/beta_cpu/full_cpu.cc: cpu/beta_cpu/full_cpu.hh: Added function to remove instructions from back of instruction list until a certain sequence number. cpu/beta_cpu/iew.hh: Stats, separate squashing behavior due to branches vs memory. cpu/beta_cpu/iew_impl.hh: Stats, separate squashing behavior for branches vs memory. cpu/beta_cpu/inst_queue.cc: Debug stuff cpu/beta_cpu/inst_queue.hh: Stats, change how mem dep unit works, debug stuff cpu/beta_cpu/inst_queue_impl.hh: Stats, change how mem dep unit works, debug stuff. Also add in parameters that used to be hardcoded. cpu/beta_cpu/mem_dep_unit.hh: cpu/beta_cpu/mem_dep_unit_impl.hh: Add in stats, change how memory dependence unit works. It now holds the memory instructions that are waiting for their memory dependences to resolve. It provides which instructions are ready directly to the IQ. cpu/beta_cpu/regfile.hh: Fix up sanity checks. cpu/beta_cpu/rename_map.cc: Fix loop variable type. cpu/beta_cpu/rob_impl.hh: Remove intermediate DynInstPtr cpu/beta_cpu/store_set.cc: Add in debugging statements. cpu/beta_cpu/store_set.hh: Reorder function arguments to match the rest of the calls. --HG-- extra : convert_revision : aabf9b1fecd1d743265dfc3b174d6159937c6f44
2004-10-22 00:02:36 +02:00
.desc("Number of squashed instructions handled by decode")
.prereq(decodeSquashedInsts);
}
template<class Impl>
void
DefaultDecode<Impl>::setTimeBuffer(TimeBuffer<TimeStruct> *tb_ptr)
{
timeBuffer = tb_ptr;
// Setup wire to write information back to fetch.
toFetch = timeBuffer->getWire(0);
// Create wires to get information from proper places in time buffer.
fromRename = timeBuffer->getWire(-renameToDecodeDelay);
fromIEW = timeBuffer->getWire(-iewToDecodeDelay);
fromCommit = timeBuffer->getWire(-commitToDecodeDelay);
}
template<class Impl>
void
DefaultDecode<Impl>::setDecodeQueue(TimeBuffer<DecodeStruct> *dq_ptr)
{
decodeQueue = dq_ptr;
// Setup wire to write information to proper place in decode queue.
toRename = decodeQueue->getWire(0);
}
template<class Impl>
void
DefaultDecode<Impl>::setFetchQueue(TimeBuffer<FetchStruct> *fq_ptr)
{
fetchQueue = fq_ptr;
// Setup wire to read information from fetch queue.
fromFetch = fetchQueue->getWire(-fetchToDecodeDelay);
}
template<class Impl>
void
DefaultDecode<Impl>::setActiveThreads(std::list<ThreadID> *at_ptr)
{
activeThreads = at_ptr;
}
template <class Impl>
bool
DefaultDecode<Impl>::drain()
{
// Decode is done draining at any time.
cpu->signalDrained();
return true;
}
template <class Impl>
void
DefaultDecode<Impl>::takeOverFrom()
{
_status = Inactive;
// Be sure to reset state and clear out any old instructions.
for (ThreadID tid = 0; tid < numThreads; ++tid) {
decodeStatus[tid] = Idle;
stalls[tid].rename = false;
stalls[tid].iew = false;
stalls[tid].commit = false;
while (!insts[tid].empty())
insts[tid].pop();
while (!skidBuffer[tid].empty())
skidBuffer[tid].pop();
branchCount[tid] = 0;
}
wroteToTimeBuffer = false;
}
template<class Impl>
bool
DefaultDecode<Impl>::checkStall(ThreadID tid) const
{
bool ret_val = false;
if (stalls[tid].rename) {
DPRINTF(Decode,"[tid:%i]: Stall fom Rename stage detected.\n", tid);
ret_val = true;
} else if (stalls[tid].iew) {
DPRINTF(Decode,"[tid:%i]: Stall fom IEW stage detected.\n", tid);
ret_val = true;
} else if (stalls[tid].commit) {
DPRINTF(Decode,"[tid:%i]: Stall fom Commit stage detected.\n", tid);
ret_val = true;
}
return ret_val;
}
Large update of several parts of my code. The most notable change is the inclusion of a full-fledged load/store queue. At the moment it still has some issues running, but most of the code is hopefully close to the final version. SConscript: arch/isa_parser.py: cpu/base_dyn_inst.cc: Remove OOO CPU stuff. arch/alpha/faults.hh: Add fake memory fault. This will be removed eventually. arch/alpha/isa_desc: Change EA comp and Mem accessor to be const StaticInstPtrs. cpu/base_dyn_inst.hh: Update read/write calls to use load queue and store queue indices. cpu/beta_cpu/alpha_dyn_inst.hh: Change to const StaticInst in the register accessors. cpu/beta_cpu/alpha_dyn_inst_impl.hh: Update syscall code with thread numbers. cpu/beta_cpu/alpha_full_cpu.hh: Alter some of the full system code so it will compile without errors. cpu/beta_cpu/alpha_full_cpu_builder.cc: Created a DerivAlphaFullCPU class so I can instantiate different CPUs that have different template parameters. cpu/beta_cpu/alpha_full_cpu_impl.hh: Update some of the full system code so it compiles. cpu/beta_cpu/alpha_params.hh: cpu/beta_cpu/fetch_impl.hh: Remove asid. cpu/beta_cpu/comm.hh: Remove global history field. cpu/beta_cpu/commit.hh: Comment out rename map. cpu/beta_cpu/commit_impl.hh: Update some of the full system code so it compiles. Also change it so that it handles memory instructions properly. cpu/beta_cpu/cpu_policy.hh: Removed IQ from the IEW template parameter to make it more uniform. cpu/beta_cpu/decode.hh: Add debug function. cpu/beta_cpu/decode_impl.hh: Slight updates for decode in the case where it causes a squash. cpu/beta_cpu/fetch.hh: cpu/beta_cpu/rob.hh: Comment out unneccessary code. cpu/beta_cpu/full_cpu.cc: Changed some of the full system code so it compiles. Updated exec contexts and so forth to hopefully make multithreading easier. cpu/beta_cpu/full_cpu.hh: Updated some of the full system code to make it compile. cpu/beta_cpu/iew.cc: Removed IQ from template parameter to IEW. cpu/beta_cpu/iew.hh: Removed IQ from template parameter to IEW. Updated IEW to recognize the Load/Store queue. cpu/beta_cpu/iew_impl.hh: New handling of memory instructions through the Load/Store queue. cpu/beta_cpu/inst_queue.hh: Updated comment. cpu/beta_cpu/inst_queue_impl.hh: Slightly different handling of memory instructions due to Load/Store queue. cpu/beta_cpu/regfile.hh: Updated full system code so it compiles. cpu/beta_cpu/rob_impl.hh: Moved some code around; no major functional changes. cpu/ooo_cpu/ooo_cpu.hh: Slight updates to OOO CPU; still does not work. cpu/static_inst.hh: Remove OOO CPU stuff. Change ea comp and mem acc to return const StaticInst. kern/kernel_stats.hh: Extra forward declares added due to compile error. --HG-- extra : convert_revision : 594a7cdbe57f6c2bda7d08856fcd864604a6238e
2005-05-03 16:56:47 +02:00
template<class Impl>
inline bool
DefaultDecode<Impl>::fetchInstsValid()
Large update of several parts of my code. The most notable change is the inclusion of a full-fledged load/store queue. At the moment it still has some issues running, but most of the code is hopefully close to the final version. SConscript: arch/isa_parser.py: cpu/base_dyn_inst.cc: Remove OOO CPU stuff. arch/alpha/faults.hh: Add fake memory fault. This will be removed eventually. arch/alpha/isa_desc: Change EA comp and Mem accessor to be const StaticInstPtrs. cpu/base_dyn_inst.hh: Update read/write calls to use load queue and store queue indices. cpu/beta_cpu/alpha_dyn_inst.hh: Change to const StaticInst in the register accessors. cpu/beta_cpu/alpha_dyn_inst_impl.hh: Update syscall code with thread numbers. cpu/beta_cpu/alpha_full_cpu.hh: Alter some of the full system code so it will compile without errors. cpu/beta_cpu/alpha_full_cpu_builder.cc: Created a DerivAlphaFullCPU class so I can instantiate different CPUs that have different template parameters. cpu/beta_cpu/alpha_full_cpu_impl.hh: Update some of the full system code so it compiles. cpu/beta_cpu/alpha_params.hh: cpu/beta_cpu/fetch_impl.hh: Remove asid. cpu/beta_cpu/comm.hh: Remove global history field. cpu/beta_cpu/commit.hh: Comment out rename map. cpu/beta_cpu/commit_impl.hh: Update some of the full system code so it compiles. Also change it so that it handles memory instructions properly. cpu/beta_cpu/cpu_policy.hh: Removed IQ from the IEW template parameter to make it more uniform. cpu/beta_cpu/decode.hh: Add debug function. cpu/beta_cpu/decode_impl.hh: Slight updates for decode in the case where it causes a squash. cpu/beta_cpu/fetch.hh: cpu/beta_cpu/rob.hh: Comment out unneccessary code. cpu/beta_cpu/full_cpu.cc: Changed some of the full system code so it compiles. Updated exec contexts and so forth to hopefully make multithreading easier. cpu/beta_cpu/full_cpu.hh: Updated some of the full system code to make it compile. cpu/beta_cpu/iew.cc: Removed IQ from template parameter to IEW. cpu/beta_cpu/iew.hh: Removed IQ from template parameter to IEW. Updated IEW to recognize the Load/Store queue. cpu/beta_cpu/iew_impl.hh: New handling of memory instructions through the Load/Store queue. cpu/beta_cpu/inst_queue.hh: Updated comment. cpu/beta_cpu/inst_queue_impl.hh: Slightly different handling of memory instructions due to Load/Store queue. cpu/beta_cpu/regfile.hh: Updated full system code so it compiles. cpu/beta_cpu/rob_impl.hh: Moved some code around; no major functional changes. cpu/ooo_cpu/ooo_cpu.hh: Slight updates to OOO CPU; still does not work. cpu/static_inst.hh: Remove OOO CPU stuff. Change ea comp and mem acc to return const StaticInst. kern/kernel_stats.hh: Extra forward declares added due to compile error. --HG-- extra : convert_revision : 594a7cdbe57f6c2bda7d08856fcd864604a6238e
2005-05-03 16:56:47 +02:00
{
return fromFetch->size > 0;
}
template<class Impl>
bool
DefaultDecode<Impl>::block(ThreadID tid)
{
DPRINTF(Decode, "[tid:%u]: Blocking.\n", tid);
// Add the current inputs to the skid buffer so they can be
// reprocessed when this stage unblocks.
skidInsert(tid);
// If the decode status is blocked or unblocking then decode has not yet
// signalled fetch to unblock. In that case, there is no need to tell
// fetch to block.
if (decodeStatus[tid] != Blocked) {
// Set the status to Blocked.
decodeStatus[tid] = Blocked;
if (decodeStatus[tid] != Unblocking) {
toFetch->decodeBlock[tid] = true;
wroteToTimeBuffer = true;
}
return true;
}
return false;
}
template<class Impl>
bool
DefaultDecode<Impl>::unblock(ThreadID tid)
{
// Decode is done unblocking only if the skid buffer is empty.
if (skidBuffer[tid].empty()) {
DPRINTF(Decode, "[tid:%u]: Done unblocking.\n", tid);
toFetch->decodeUnblock[tid] = true;
wroteToTimeBuffer = true;
decodeStatus[tid] = Running;
return true;
}
DPRINTF(Decode, "[tid:%u]: Currently unblocking.\n", tid);
return false;
}
template<class Impl>
void
DefaultDecode<Impl>::squash(DynInstPtr &inst, ThreadID tid)
{
ISA,CPU,etc: Create an ISA defined PC type that abstracts out ISA behaviors. This change is a low level and pervasive reorganization of how PCs are managed in M5. Back when Alpha was the only ISA, there were only 2 PCs to worry about, the PC and the NPC, and the lsb of the PC signaled whether or not you were in PAL mode. As other ISAs were added, we had to add an NNPC, micro PC and next micropc, x86 and ARM introduced variable length instruction sets, and ARM started to keep track of mode bits in the PC. Each CPU model handled PCs in its own custom way that needed to be updated individually to handle the new dimensions of variability, or, in the case of ARMs mode-bit-in-the-pc hack, the complexity could be hidden in the ISA at the ISA implementation's expense. Areas like the branch predictor hadn't been updated to handle branch delay slots or micropcs, and it turns out that had introduced a significant (10s of percent) performance bug in SPARC and to a lesser extend MIPS. Rather than perpetuate the problem by reworking O3 again to handle the PC features needed by x86, this change was introduced to rework PC handling in a more modular, transparent, and hopefully efficient way. PC type: Rather than having the superset of all possible elements of PC state declared in each of the CPU models, each ISA defines its own PCState type which has exactly the elements it needs. A cross product of canned PCState classes are defined in the new "generic" ISA directory for ISAs with/without delay slots and microcode. These are either typedef-ed or subclassed by each ISA. To read or write this structure through a *Context, you use the new pcState() accessor which reads or writes depending on whether it has an argument. If you just want the address of the current or next instruction or the current micro PC, you can get those through read-only accessors on either the PCState type or the *Contexts. These are instAddr(), nextInstAddr(), and microPC(). Note the move away from readPC. That name is ambiguous since it's not clear whether or not it should be the actual address to fetch from, or if it should have extra bits in it like the PAL mode bit. Each class is free to define its own functions to get at whatever values it needs however it needs to to be used in ISA specific code. Eventually Alpha's PAL mode bit could be moved out of the PC and into a separate field like ARM. These types can be reset to a particular pc (where npc = pc + sizeof(MachInst), nnpc = npc + sizeof(MachInst), upc = 0, nupc = 1 as appropriate), printed, serialized, and compared. There is a branching() function which encapsulates code in the CPU models that checked if an instruction branched or not. Exactly what that means in the context of branch delay slots which can skip an instruction when not taken is ambiguous, and ideally this function and its uses can be eliminated. PCStates also generally know how to advance themselves in various ways depending on if they point at an instruction, a microop, or the last microop of a macroop. More on that later. Ideally, accessing all the PCs at once when setting them will improve performance of M5 even though more data needs to be moved around. This is because often all the PCs need to be manipulated together, and by getting them all at once you avoid multiple function calls. Also, the PCs of a particular thread will have spatial locality in the cache. Previously they were grouped by element in arrays which spread out accesses. Advancing the PC: The PCs were previously managed entirely by the CPU which had to know about PC semantics, try to figure out which dimension to increment the PC in, what to set NPC/NNPC, etc. These decisions are best left to the ISA in conjunction with the PC type itself. Because most of the information about how to increment the PC (mainly what type of instruction it refers to) is contained in the instruction object, a new advancePC virtual function was added to the StaticInst class. Subclasses provide an implementation that moves around the right element of the PC with a minimal amount of decision making. In ISAs like Alpha, the instructions always simply assign NPC to PC without having to worry about micropcs, nnpcs, etc. The added cost of a virtual function call should be outweighed by not having to figure out as much about what to do with the PCs and mucking around with the extra elements. One drawback of making the StaticInsts advance the PC is that you have to actually have one to advance the PC. This would, superficially, seem to require decoding an instruction before fetch could advance. This is, as far as I can tell, realistic. fetch would advance through memory addresses, not PCs, perhaps predicting new memory addresses using existing ones. More sophisticated decisions about control flow would be made later on, after the instruction was decoded, and handed back to fetch. If branching needs to happen, some amount of decoding needs to happen to see that it's a branch, what the target is, etc. This could get a little more complicated if that gets done by the predecoder, but I'm choosing to ignore that for now. Variable length instructions: To handle variable length instructions in x86 and ARM, the predecoder now takes in the current PC by reference to the getExtMachInst function. It can modify the PC however it needs to (by setting NPC to be the PC + instruction length, for instance). This could be improved since the CPU doesn't know if the PC was modified and always has to write it back. ISA parser: To support the new API, all PC related operand types were removed from the parser and replaced with a PCState type. There are two warts on this implementation. First, as with all the other operand types, the PCState still has to have a valid operand type even though it doesn't use it. Second, using syntax like PCS.npc(target) doesn't work for two reasons, this looks like the syntax for operand type overriding, and the parser can't figure out if you're reading or writing. Instructions that use the PCS operand (which I've consistently called it) need to first read it into a local variable, manipulate it, and then write it back out. Return address stack: The return address stack needed a little extra help because, in the presence of branch delay slots, it has to merge together elements of the return PC and the call PC. To handle that, a buildRetPC utility function was added. There are basically only two versions in all the ISAs, but it didn't seem short enough to put into the generic ISA directory. Also, the branch predictor code in O3 and InOrder were adjusted so that they always store the PC of the actual call instruction in the RAS, not the next PC. If the call instruction is a microop, the next PC refers to the next microop in the same macroop which is probably not desirable. The buildRetPC function advances the PC intelligently to the next macroop (in an ISA specific way) so that that case works. Change in stats: There were no change in stats except in MIPS and SPARC in the O3 model. MIPS runs in about 9% fewer ticks. SPARC runs with 30%-50% fewer ticks, which could likely be improved further by setting call/return instruction flags and taking advantage of the RAS. TODO: Add != operators to the PCState classes, defined trivially to be !(a==b). Smooth out places where PCs are split apart, passed around, and put back together later. I think this might happen in SPARC's fault code. Add ISA specific constructors that allow setting PC elements without calling a bunch of accessors. Try to eliminate the need for the branching() function. Factor out Alpha's PAL mode pc bit into a separate flag field, and eliminate places where it's blindly masked out or tested in the PC.
2010-10-31 08:07:20 +01:00
DPRINTF(Decode, "[tid:%i]: [sn:%i] Squashing due to incorrect branch "
"prediction detected at decode.\n", tid, inst->seqNum);
// Send back mispredict information.
toFetch->decodeInfo[tid].branchMispredict = true;
toFetch->decodeInfo[tid].predIncorrect = true;
toFetch->decodeInfo[tid].squash = true;
toFetch->decodeInfo[tid].doneSeqNum = inst->seqNum;
toFetch->decodeInfo[tid].nextPC = inst->branchTarget();
ISA,CPU,etc: Create an ISA defined PC type that abstracts out ISA behaviors. This change is a low level and pervasive reorganization of how PCs are managed in M5. Back when Alpha was the only ISA, there were only 2 PCs to worry about, the PC and the NPC, and the lsb of the PC signaled whether or not you were in PAL mode. As other ISAs were added, we had to add an NNPC, micro PC and next micropc, x86 and ARM introduced variable length instruction sets, and ARM started to keep track of mode bits in the PC. Each CPU model handled PCs in its own custom way that needed to be updated individually to handle the new dimensions of variability, or, in the case of ARMs mode-bit-in-the-pc hack, the complexity could be hidden in the ISA at the ISA implementation's expense. Areas like the branch predictor hadn't been updated to handle branch delay slots or micropcs, and it turns out that had introduced a significant (10s of percent) performance bug in SPARC and to a lesser extend MIPS. Rather than perpetuate the problem by reworking O3 again to handle the PC features needed by x86, this change was introduced to rework PC handling in a more modular, transparent, and hopefully efficient way. PC type: Rather than having the superset of all possible elements of PC state declared in each of the CPU models, each ISA defines its own PCState type which has exactly the elements it needs. A cross product of canned PCState classes are defined in the new "generic" ISA directory for ISAs with/without delay slots and microcode. These are either typedef-ed or subclassed by each ISA. To read or write this structure through a *Context, you use the new pcState() accessor which reads or writes depending on whether it has an argument. If you just want the address of the current or next instruction or the current micro PC, you can get those through read-only accessors on either the PCState type or the *Contexts. These are instAddr(), nextInstAddr(), and microPC(). Note the move away from readPC. That name is ambiguous since it's not clear whether or not it should be the actual address to fetch from, or if it should have extra bits in it like the PAL mode bit. Each class is free to define its own functions to get at whatever values it needs however it needs to to be used in ISA specific code. Eventually Alpha's PAL mode bit could be moved out of the PC and into a separate field like ARM. These types can be reset to a particular pc (where npc = pc + sizeof(MachInst), nnpc = npc + sizeof(MachInst), upc = 0, nupc = 1 as appropriate), printed, serialized, and compared. There is a branching() function which encapsulates code in the CPU models that checked if an instruction branched or not. Exactly what that means in the context of branch delay slots which can skip an instruction when not taken is ambiguous, and ideally this function and its uses can be eliminated. PCStates also generally know how to advance themselves in various ways depending on if they point at an instruction, a microop, or the last microop of a macroop. More on that later. Ideally, accessing all the PCs at once when setting them will improve performance of M5 even though more data needs to be moved around. This is because often all the PCs need to be manipulated together, and by getting them all at once you avoid multiple function calls. Also, the PCs of a particular thread will have spatial locality in the cache. Previously they were grouped by element in arrays which spread out accesses. Advancing the PC: The PCs were previously managed entirely by the CPU which had to know about PC semantics, try to figure out which dimension to increment the PC in, what to set NPC/NNPC, etc. These decisions are best left to the ISA in conjunction with the PC type itself. Because most of the information about how to increment the PC (mainly what type of instruction it refers to) is contained in the instruction object, a new advancePC virtual function was added to the StaticInst class. Subclasses provide an implementation that moves around the right element of the PC with a minimal amount of decision making. In ISAs like Alpha, the instructions always simply assign NPC to PC without having to worry about micropcs, nnpcs, etc. The added cost of a virtual function call should be outweighed by not having to figure out as much about what to do with the PCs and mucking around with the extra elements. One drawback of making the StaticInsts advance the PC is that you have to actually have one to advance the PC. This would, superficially, seem to require decoding an instruction before fetch could advance. This is, as far as I can tell, realistic. fetch would advance through memory addresses, not PCs, perhaps predicting new memory addresses using existing ones. More sophisticated decisions about control flow would be made later on, after the instruction was decoded, and handed back to fetch. If branching needs to happen, some amount of decoding needs to happen to see that it's a branch, what the target is, etc. This could get a little more complicated if that gets done by the predecoder, but I'm choosing to ignore that for now. Variable length instructions: To handle variable length instructions in x86 and ARM, the predecoder now takes in the current PC by reference to the getExtMachInst function. It can modify the PC however it needs to (by setting NPC to be the PC + instruction length, for instance). This could be improved since the CPU doesn't know if the PC was modified and always has to write it back. ISA parser: To support the new API, all PC related operand types were removed from the parser and replaced with a PCState type. There are two warts on this implementation. First, as with all the other operand types, the PCState still has to have a valid operand type even though it doesn't use it. Second, using syntax like PCS.npc(target) doesn't work for two reasons, this looks like the syntax for operand type overriding, and the parser can't figure out if you're reading or writing. Instructions that use the PCS operand (which I've consistently called it) need to first read it into a local variable, manipulate it, and then write it back out. Return address stack: The return address stack needed a little extra help because, in the presence of branch delay slots, it has to merge together elements of the return PC and the call PC. To handle that, a buildRetPC utility function was added. There are basically only two versions in all the ISAs, but it didn't seem short enough to put into the generic ISA directory. Also, the branch predictor code in O3 and InOrder were adjusted so that they always store the PC of the actual call instruction in the RAS, not the next PC. If the call instruction is a microop, the next PC refers to the next microop in the same macroop which is probably not desirable. The buildRetPC function advances the PC intelligently to the next macroop (in an ISA specific way) so that that case works. Change in stats: There were no change in stats except in MIPS and SPARC in the O3 model. MIPS runs in about 9% fewer ticks. SPARC runs with 30%-50% fewer ticks, which could likely be improved further by setting call/return instruction flags and taking advantage of the RAS. TODO: Add != operators to the PCState classes, defined trivially to be !(a==b). Smooth out places where PCs are split apart, passed around, and put back together later. I think this might happen in SPARC's fault code. Add ISA specific constructors that allow setting PC elements without calling a bunch of accessors. Try to eliminate the need for the branching() function. Factor out Alpha's PAL mode pc bit into a separate flag field, and eliminate places where it's blindly masked out or tested in the PC.
2010-10-31 08:07:20 +01:00
toFetch->decodeInfo[tid].branchTaken = inst->pcState().branching();
InstSeqNum squash_seq_num = inst->seqNum;
This changeset gets the MIPS ISA pretty much working in the O3CPU. It builds, runs, and gets very very close to completing the hello world succesfully but there are some minor quirks to iron out. Who would've known a DELAY SLOT introduces that much complexity?! arrgh! Anyways, a lot of this stuff had to do with my project at MIPS and me needing to know how I was going to get this working for the MIPS ISA. So I figured I would try to touch it up and throw it in here (I hate to introduce non-completely working components... ) src/arch/alpha/isa/mem.isa: spacing src/arch/mips/faults.cc: src/arch/mips/faults.hh: Gabe really authored this src/arch/mips/isa/decoder.isa: add StoreConditional Flag to instruction src/arch/mips/isa/formats/basic.isa: Steven really did this file src/arch/mips/isa/formats/branch.isa: fix bug for uncond/cond control src/arch/mips/isa/formats/mem.isa: Adjust O3CPU memory access to use new memory model interface. src/arch/mips/isa/formats/util.isa: update LoadStoreBase template src/arch/mips/isa_traits.cc: update SERIALIZE partially src/arch/mips/process.cc: src/arch/mips/process.hh: no need for this for NOW. ASID/Virtual addressing handles it src/arch/mips/regfile/misc_regfile.hh: add in clear() function and comments for future usage of special misc. regs src/cpu/base_dyn_inst.hh: add in nextNPC variable and supporting functions. add isCondDelaySlot function Update predTaken and mispredicted functions src/cpu/base_dyn_inst_impl.hh: init nextNPC src/cpu/o3/SConscript: add MIPS files to compile src/cpu/o3/alpha/thread_context.hh: no need for my name on this file src/cpu/o3/bpred_unit_impl.hh: Update RAS appropriately for MIPS src/cpu/o3/comm.hh: add some extra communication variables to aid in handling the delay slots src/cpu/o3/commit.hh: minor name fix for nextNPC functions. src/cpu/o3/commit_impl.hh: src/cpu/o3/decode_impl.hh: src/cpu/o3/fetch_impl.hh: src/cpu/o3/iew_impl.hh: src/cpu/o3/inst_queue_impl.hh: src/cpu/o3/rename_impl.hh: Fix necessary variables and functions for squashes with delay slots src/cpu/o3/cpu.cc: Update function interface ... adjust removeInstsNotInROB function to recognize delay slots insts src/cpu/o3/cpu.hh: update removeInstsNotInROB src/cpu/o3/decode.hh: declare necessary variables for handling delay slot src/cpu/o3/dyn_inst.hh: Add in MipsDynInst src/cpu/o3/fetch.hh: src/cpu/o3/iew.hh: src/cpu/o3/rename.hh: declare necessary variables and adjust functions for handling delay slot src/cpu/o3/inst_queue.hh: src/cpu/simple/base.cc: no need for my name here src/cpu/o3/isa_specific.hh: add in MIPS files src/cpu/o3/scoreboard.hh: dont include alpha specific isa traits! src/cpu/o3/thread_context.hh: no need for my name here, i just rearranged where the file goes src/cpu/static_inst.hh: add isCondDelaySlot function src/cpu/o3/mips/cpu.cc: src/cpu/o3/mips/cpu.hh: src/cpu/o3/mips/cpu_builder.cc: src/cpu/o3/mips/cpu_impl.hh: src/cpu/o3/mips/dyn_inst.cc: src/cpu/o3/mips/dyn_inst.hh: src/cpu/o3/mips/dyn_inst_impl.hh: src/cpu/o3/mips/impl.hh: src/cpu/o3/mips/params.hh: src/cpu/o3/mips/thread_context.cc: src/cpu/o3/mips/thread_context.hh: MIPS file for O3CPU...mirrors ALPHA definition --HG-- extra : convert_revision : 9bb199b4085903e49ffd5a4c8ac44d11460d988c
2006-07-23 19:39:42 +02:00
// Might have to tell fetch to unblock.
if (decodeStatus[tid] == Blocked ||
decodeStatus[tid] == Unblocking) {
toFetch->decodeUnblock[tid] = 1;
}
// Set status to squashing.
decodeStatus[tid] = Squashing;
for (int i=0; i<fromFetch->size; i++) {
if (fromFetch->insts[i]->threadNumber == tid &&
This changeset gets the MIPS ISA pretty much working in the O3CPU. It builds, runs, and gets very very close to completing the hello world succesfully but there are some minor quirks to iron out. Who would've known a DELAY SLOT introduces that much complexity?! arrgh! Anyways, a lot of this stuff had to do with my project at MIPS and me needing to know how I was going to get this working for the MIPS ISA. So I figured I would try to touch it up and throw it in here (I hate to introduce non-completely working components... ) src/arch/alpha/isa/mem.isa: spacing src/arch/mips/faults.cc: src/arch/mips/faults.hh: Gabe really authored this src/arch/mips/isa/decoder.isa: add StoreConditional Flag to instruction src/arch/mips/isa/formats/basic.isa: Steven really did this file src/arch/mips/isa/formats/branch.isa: fix bug for uncond/cond control src/arch/mips/isa/formats/mem.isa: Adjust O3CPU memory access to use new memory model interface. src/arch/mips/isa/formats/util.isa: update LoadStoreBase template src/arch/mips/isa_traits.cc: update SERIALIZE partially src/arch/mips/process.cc: src/arch/mips/process.hh: no need for this for NOW. ASID/Virtual addressing handles it src/arch/mips/regfile/misc_regfile.hh: add in clear() function and comments for future usage of special misc. regs src/cpu/base_dyn_inst.hh: add in nextNPC variable and supporting functions. add isCondDelaySlot function Update predTaken and mispredicted functions src/cpu/base_dyn_inst_impl.hh: init nextNPC src/cpu/o3/SConscript: add MIPS files to compile src/cpu/o3/alpha/thread_context.hh: no need for my name on this file src/cpu/o3/bpred_unit_impl.hh: Update RAS appropriately for MIPS src/cpu/o3/comm.hh: add some extra communication variables to aid in handling the delay slots src/cpu/o3/commit.hh: minor name fix for nextNPC functions. src/cpu/o3/commit_impl.hh: src/cpu/o3/decode_impl.hh: src/cpu/o3/fetch_impl.hh: src/cpu/o3/iew_impl.hh: src/cpu/o3/inst_queue_impl.hh: src/cpu/o3/rename_impl.hh: Fix necessary variables and functions for squashes with delay slots src/cpu/o3/cpu.cc: Update function interface ... adjust removeInstsNotInROB function to recognize delay slots insts src/cpu/o3/cpu.hh: update removeInstsNotInROB src/cpu/o3/decode.hh: declare necessary variables for handling delay slot src/cpu/o3/dyn_inst.hh: Add in MipsDynInst src/cpu/o3/fetch.hh: src/cpu/o3/iew.hh: src/cpu/o3/rename.hh: declare necessary variables and adjust functions for handling delay slot src/cpu/o3/inst_queue.hh: src/cpu/simple/base.cc: no need for my name here src/cpu/o3/isa_specific.hh: add in MIPS files src/cpu/o3/scoreboard.hh: dont include alpha specific isa traits! src/cpu/o3/thread_context.hh: no need for my name here, i just rearranged where the file goes src/cpu/static_inst.hh: add isCondDelaySlot function src/cpu/o3/mips/cpu.cc: src/cpu/o3/mips/cpu.hh: src/cpu/o3/mips/cpu_builder.cc: src/cpu/o3/mips/cpu_impl.hh: src/cpu/o3/mips/dyn_inst.cc: src/cpu/o3/mips/dyn_inst.hh: src/cpu/o3/mips/dyn_inst_impl.hh: src/cpu/o3/mips/impl.hh: src/cpu/o3/mips/params.hh: src/cpu/o3/mips/thread_context.cc: src/cpu/o3/mips/thread_context.hh: MIPS file for O3CPU...mirrors ALPHA definition --HG-- extra : convert_revision : 9bb199b4085903e49ffd5a4c8ac44d11460d988c
2006-07-23 19:39:42 +02:00
fromFetch->insts[i]->seqNum > squash_seq_num) {
fromFetch->insts[i]->setSquashed();
}
}
// Clear the instruction list and skid buffer in case they have any
// insts in them.
while (!insts[tid].empty()) {
insts[tid].pop();
}
while (!skidBuffer[tid].empty()) {
skidBuffer[tid].pop();
}
Large update of several parts of my code. The most notable change is the inclusion of a full-fledged load/store queue. At the moment it still has some issues running, but most of the code is hopefully close to the final version. SConscript: arch/isa_parser.py: cpu/base_dyn_inst.cc: Remove OOO CPU stuff. arch/alpha/faults.hh: Add fake memory fault. This will be removed eventually. arch/alpha/isa_desc: Change EA comp and Mem accessor to be const StaticInstPtrs. cpu/base_dyn_inst.hh: Update read/write calls to use load queue and store queue indices. cpu/beta_cpu/alpha_dyn_inst.hh: Change to const StaticInst in the register accessors. cpu/beta_cpu/alpha_dyn_inst_impl.hh: Update syscall code with thread numbers. cpu/beta_cpu/alpha_full_cpu.hh: Alter some of the full system code so it will compile without errors. cpu/beta_cpu/alpha_full_cpu_builder.cc: Created a DerivAlphaFullCPU class so I can instantiate different CPUs that have different template parameters. cpu/beta_cpu/alpha_full_cpu_impl.hh: Update some of the full system code so it compiles. cpu/beta_cpu/alpha_params.hh: cpu/beta_cpu/fetch_impl.hh: Remove asid. cpu/beta_cpu/comm.hh: Remove global history field. cpu/beta_cpu/commit.hh: Comment out rename map. cpu/beta_cpu/commit_impl.hh: Update some of the full system code so it compiles. Also change it so that it handles memory instructions properly. cpu/beta_cpu/cpu_policy.hh: Removed IQ from the IEW template parameter to make it more uniform. cpu/beta_cpu/decode.hh: Add debug function. cpu/beta_cpu/decode_impl.hh: Slight updates for decode in the case where it causes a squash. cpu/beta_cpu/fetch.hh: cpu/beta_cpu/rob.hh: Comment out unneccessary code. cpu/beta_cpu/full_cpu.cc: Changed some of the full system code so it compiles. Updated exec contexts and so forth to hopefully make multithreading easier. cpu/beta_cpu/full_cpu.hh: Updated some of the full system code to make it compile. cpu/beta_cpu/iew.cc: Removed IQ from template parameter to IEW. cpu/beta_cpu/iew.hh: Removed IQ from template parameter to IEW. Updated IEW to recognize the Load/Store queue. cpu/beta_cpu/iew_impl.hh: New handling of memory instructions through the Load/Store queue. cpu/beta_cpu/inst_queue.hh: Updated comment. cpu/beta_cpu/inst_queue_impl.hh: Slightly different handling of memory instructions due to Load/Store queue. cpu/beta_cpu/regfile.hh: Updated full system code so it compiles. cpu/beta_cpu/rob_impl.hh: Moved some code around; no major functional changes. cpu/ooo_cpu/ooo_cpu.hh: Slight updates to OOO CPU; still does not work. cpu/static_inst.hh: Remove OOO CPU stuff. Change ea comp and mem acc to return const StaticInst. kern/kernel_stats.hh: Extra forward declares added due to compile error. --HG-- extra : convert_revision : 594a7cdbe57f6c2bda7d08856fcd864604a6238e
2005-05-03 16:56:47 +02:00
// Squash instructions up until this one
This changeset gets the MIPS ISA pretty much working in the O3CPU. It builds, runs, and gets very very close to completing the hello world succesfully but there are some minor quirks to iron out. Who would've known a DELAY SLOT introduces that much complexity?! arrgh! Anyways, a lot of this stuff had to do with my project at MIPS and me needing to know how I was going to get this working for the MIPS ISA. So I figured I would try to touch it up and throw it in here (I hate to introduce non-completely working components... ) src/arch/alpha/isa/mem.isa: spacing src/arch/mips/faults.cc: src/arch/mips/faults.hh: Gabe really authored this src/arch/mips/isa/decoder.isa: add StoreConditional Flag to instruction src/arch/mips/isa/formats/basic.isa: Steven really did this file src/arch/mips/isa/formats/branch.isa: fix bug for uncond/cond control src/arch/mips/isa/formats/mem.isa: Adjust O3CPU memory access to use new memory model interface. src/arch/mips/isa/formats/util.isa: update LoadStoreBase template src/arch/mips/isa_traits.cc: update SERIALIZE partially src/arch/mips/process.cc: src/arch/mips/process.hh: no need for this for NOW. ASID/Virtual addressing handles it src/arch/mips/regfile/misc_regfile.hh: add in clear() function and comments for future usage of special misc. regs src/cpu/base_dyn_inst.hh: add in nextNPC variable and supporting functions. add isCondDelaySlot function Update predTaken and mispredicted functions src/cpu/base_dyn_inst_impl.hh: init nextNPC src/cpu/o3/SConscript: add MIPS files to compile src/cpu/o3/alpha/thread_context.hh: no need for my name on this file src/cpu/o3/bpred_unit_impl.hh: Update RAS appropriately for MIPS src/cpu/o3/comm.hh: add some extra communication variables to aid in handling the delay slots src/cpu/o3/commit.hh: minor name fix for nextNPC functions. src/cpu/o3/commit_impl.hh: src/cpu/o3/decode_impl.hh: src/cpu/o3/fetch_impl.hh: src/cpu/o3/iew_impl.hh: src/cpu/o3/inst_queue_impl.hh: src/cpu/o3/rename_impl.hh: Fix necessary variables and functions for squashes with delay slots src/cpu/o3/cpu.cc: Update function interface ... adjust removeInstsNotInROB function to recognize delay slots insts src/cpu/o3/cpu.hh: update removeInstsNotInROB src/cpu/o3/decode.hh: declare necessary variables for handling delay slot src/cpu/o3/dyn_inst.hh: Add in MipsDynInst src/cpu/o3/fetch.hh: src/cpu/o3/iew.hh: src/cpu/o3/rename.hh: declare necessary variables and adjust functions for handling delay slot src/cpu/o3/inst_queue.hh: src/cpu/simple/base.cc: no need for my name here src/cpu/o3/isa_specific.hh: add in MIPS files src/cpu/o3/scoreboard.hh: dont include alpha specific isa traits! src/cpu/o3/thread_context.hh: no need for my name here, i just rearranged where the file goes src/cpu/static_inst.hh: add isCondDelaySlot function src/cpu/o3/mips/cpu.cc: src/cpu/o3/mips/cpu.hh: src/cpu/o3/mips/cpu_builder.cc: src/cpu/o3/mips/cpu_impl.hh: src/cpu/o3/mips/dyn_inst.cc: src/cpu/o3/mips/dyn_inst.hh: src/cpu/o3/mips/dyn_inst_impl.hh: src/cpu/o3/mips/impl.hh: src/cpu/o3/mips/params.hh: src/cpu/o3/mips/thread_context.cc: src/cpu/o3/mips/thread_context.hh: MIPS file for O3CPU...mirrors ALPHA definition --HG-- extra : convert_revision : 9bb199b4085903e49ffd5a4c8ac44d11460d988c
2006-07-23 19:39:42 +02:00
cpu->removeInstsUntil(squash_seq_num, tid);
}
template<class Impl>
unsigned
DefaultDecode<Impl>::squash(ThreadID tid)
{
DPRINTF(Decode, "[tid:%i]: Squashing.\n",tid);
if (decodeStatus[tid] == Blocked ||
decodeStatus[tid] == Unblocking) {
#if !FULL_SYSTEM
// In syscall emulation, we can have both a block and a squash due
// to a syscall in the same cycle. This would cause both signals to
// be high. This shouldn't happen in full system.
// @todo: Determine if this still happens.
if (toFetch->decodeBlock[tid]) {
toFetch->decodeBlock[tid] = 0;
} else {
toFetch->decodeUnblock[tid] = 1;
}
#else
toFetch->decodeUnblock[tid] = 1;
#endif
}
// Set status to squashing.
decodeStatus[tid] = Squashing;
// Go through incoming instructions from fetch and squash them.
unsigned squash_count = 0;
for (int i=0; i<fromFetch->size; i++) {
if (fromFetch->insts[i]->threadNumber == tid) {
fromFetch->insts[i]->setSquashed();
squash_count++;
}
}
// Clear the instruction list and skid buffer in case they have any
// insts in them.
while (!insts[tid].empty()) {
insts[tid].pop();
}
while (!skidBuffer[tid].empty()) {
skidBuffer[tid].pop();
}
return squash_count;
}
template<class Impl>
void
DefaultDecode<Impl>::skidInsert(ThreadID tid)
{
DynInstPtr inst = NULL;
while (!insts[tid].empty()) {
inst = insts[tid].front();
insts[tid].pop();
Check in of various updates to the CPU. Mainly adds in stats, improves branch prediction, and makes memory dependence work properly. SConscript: Added return address stack, tournament predictor. cpu/base_cpu.cc: Added debug break and print statements. cpu/base_dyn_inst.cc: cpu/base_dyn_inst.hh: Comment out possibly unneeded variables. cpu/beta_cpu/2bit_local_pred.cc: 2bit predictor no longer speculatively updates itself. cpu/beta_cpu/alpha_dyn_inst.hh: Comment formatting. cpu/beta_cpu/alpha_full_cpu.hh: Formatting cpu/beta_cpu/alpha_full_cpu_builder.cc: Added new parameters for branch predictors, and IQ parameters. cpu/beta_cpu/alpha_full_cpu_impl.hh: Register stats. cpu/beta_cpu/alpha_params.hh: Added parameters for IQ, branch predictors, and store sets. cpu/beta_cpu/bpred_unit.cc: Removed one class. cpu/beta_cpu/bpred_unit.hh: Add in RAS, stats. Changed branch predictor unit functionality so that it holds a history of past branches so it can update, and also hold a proper history of the RAS so it can be restored on branch mispredicts. cpu/beta_cpu/bpred_unit_impl.hh: Added in stats, history of branches, RAS. Now bpred unit actually modifies the instruction's predicted next PC. cpu/beta_cpu/btb.cc: Add in sanity checks. cpu/beta_cpu/comm.hh: Add in communication where needed, remove it where it's not. cpu/beta_cpu/commit.hh: cpu/beta_cpu/rename.hh: cpu/beta_cpu/rename_impl.hh: Add in stats. cpu/beta_cpu/commit_impl.hh: Stats, update what is sent back on branch mispredict. cpu/beta_cpu/cpu_policy.hh: Change the bpred unit being used. cpu/beta_cpu/decode.hh: cpu/beta_cpu/decode_impl.hh: Stats. cpu/beta_cpu/fetch.hh: Stats, change squash so it can handle squashes from decode differently than squashes from commit. cpu/beta_cpu/fetch_impl.hh: Add in stats. Change how a cache line is fetched. Update to work with caches. Also have separate functions for different behavior if squash is coming from decode vs commit. cpu/beta_cpu/free_list.hh: Remove some old comments. cpu/beta_cpu/full_cpu.cc: cpu/beta_cpu/full_cpu.hh: Added function to remove instructions from back of instruction list until a certain sequence number. cpu/beta_cpu/iew.hh: Stats, separate squashing behavior due to branches vs memory. cpu/beta_cpu/iew_impl.hh: Stats, separate squashing behavior for branches vs memory. cpu/beta_cpu/inst_queue.cc: Debug stuff cpu/beta_cpu/inst_queue.hh: Stats, change how mem dep unit works, debug stuff cpu/beta_cpu/inst_queue_impl.hh: Stats, change how mem dep unit works, debug stuff. Also add in parameters that used to be hardcoded. cpu/beta_cpu/mem_dep_unit.hh: cpu/beta_cpu/mem_dep_unit_impl.hh: Add in stats, change how memory dependence unit works. It now holds the memory instructions that are waiting for their memory dependences to resolve. It provides which instructions are ready directly to the IQ. cpu/beta_cpu/regfile.hh: Fix up sanity checks. cpu/beta_cpu/rename_map.cc: Fix loop variable type. cpu/beta_cpu/rob_impl.hh: Remove intermediate DynInstPtr cpu/beta_cpu/store_set.cc: Add in debugging statements. cpu/beta_cpu/store_set.hh: Reorder function arguments to match the rest of the calls. --HG-- extra : convert_revision : aabf9b1fecd1d743265dfc3b174d6159937c6f44
2004-10-22 00:02:36 +02:00
assert(tid == inst->threadNumber);
Update to make multiple instruction issue and different latencies work. Also change to ref counted DynInst. SConscript: Add branch predictor, BTB, load store queue, and storesets. arch/isa_parser.py: Specify the template parameter for AlphaDynInst base/traceflags.py: Add load store queue, store set, and mem dependence unit to the list of trace flags. cpu/base_dyn_inst.cc: Change formating, add in debug statement. cpu/base_dyn_inst.hh: Change DynInst to be RefCounted, add flag to clear whether or not this instruction can commit. This is likely to be removed in the future. cpu/beta_cpu/alpha_dyn_inst.cc: AlphaDynInst has been changed to be templated, so now this CC file is just used to force instantiations of AlphaDynInst. cpu/beta_cpu/alpha_dyn_inst.hh: Changed AlphaDynInst to be templated on Impl. Removed some unnecessary functions. cpu/beta_cpu/alpha_full_cpu.cc: AlphaFullCPU has been changed to be templated, so this CC file is now just used to force instantation of AlphaFullCPU. cpu/beta_cpu/alpha_full_cpu.hh: Change AlphaFullCPU to be templated on Impl. cpu/beta_cpu/alpha_impl.hh: Update it to reflect AlphaDynInst and AlphaFullCPU being templated on Impl. Also removed time buffers from here, as they are really a part of the CPU and are thus in the CPU policy now. cpu/beta_cpu/alpha_params.hh: Make AlphaSimpleParams inherit from the BaseFullCPU so that it doesn't need to specifically declare any parameters that are already in the BaseFullCPU. cpu/beta_cpu/comm.hh: Changed the structure of the time buffer communication structs. Now they include the size of the packet of instructions it is sending. Added some parameters to the backwards communication struct, mainly for squashing. cpu/beta_cpu/commit.hh: Update typenames to reflect change in location of time buffer structs. Update DynInst to DynInstPtr (it is refcounted now). cpu/beta_cpu/commit_impl.hh: Formatting changes mainly. Also sends back proper information on branch mispredicts so that the bpred unit can update itself. Updated behavior for non-speculative instructions (stores, any other non-spec instructions): once they reach the head of the ROB, the ROB signals back to the IQ that it can go ahead and issue the non-speculative instruction. The instruction itself is updated so that commit won't try to commit it again until it is done executing. cpu/beta_cpu/cpu_policy.hh: Added branch prediction unit, mem dependence prediction unit, load store queue. Moved time buffer structs from AlphaSimpleImpl to here. cpu/beta_cpu/decode.hh: Changed typedefs to reflect change in location of time buffer structs and also the change from DynInst to ref counted DynInstPtr. cpu/beta_cpu/decode_impl.hh: Continues to buffer instructions even while unblocking now. Changed how it loops through groups of instructions so it can properly block during the middle of a group of instructions. cpu/beta_cpu/fetch.hh: Changed typedefs to reflect change in location of time buffer structs and the change to ref counted DynInsts. Also added in branch brediction unit. cpu/beta_cpu/fetch_impl.hh: Add in branch prediction. Changed how fetch checks inputs and its current state to make for easier logic. cpu/beta_cpu/free_list.cc: Changed int regs and float regs to logically use one flat namespace. Future change will be moving them to a single scoreboard to conserve space. cpu/beta_cpu/free_list.hh: Mostly debugging statements. Might be removed for performance in future. cpu/beta_cpu/full_cpu.cc: Added in some debugging statements. Updated BaseFullCPU to take a params object. cpu/beta_cpu/full_cpu.hh: Added params class within BaseCPU that other param classes will be able to inherit from. Updated typedefs to reflect change in location of time buffer structs and ref counted DynInst. cpu/beta_cpu/iew.hh: Updated typedefs to reflect change in location of time buffer structs and use of ref counted DynInsts. cpu/beta_cpu/iew_impl.hh: Added in load store queue, updated iew to be able to execute non- speculative instructions, instead of having them execute in commit. cpu/beta_cpu/inst_queue.hh: Updated change to ref counted DynInsts. Changed inst queue to hold non-speculative instructions as well, which are issued only when commit signals backwards that a nonspeculative instruction is at the head of the ROB. cpu/beta_cpu/inst_queue_impl.hh: Updated to allow for non-speculative instructions to be in the inst queue. Also added some debug functions. cpu/beta_cpu/regfile.hh: Added debugging statements, changed formatting. cpu/beta_cpu/rename.hh: Updated typedefs, added some functions to clean up code. cpu/beta_cpu/rename_impl.hh: Moved some code into functions to make it easier to read. cpu/beta_cpu/rename_map.cc: Changed int and float reg behavior to use a single flat namespace. In the future, the rename maps can be combined to a single rename map to save space. cpu/beta_cpu/rename_map.hh: Added destructor. cpu/beta_cpu/rob.hh: Updated it with change from DynInst to ref counted DynInst. cpu/beta_cpu/rob_impl.hh: Formatting, updated to use ref counted DynInst. cpu/static_inst.hh: Updated forward declaration for AlphaDynInst now that it is templated. --HG-- extra : convert_revision : 1045f240ee9b6a4bd368e1806aca029ebbdc6dd3
2004-09-23 20:06:03 +02:00
ISA,CPU,etc: Create an ISA defined PC type that abstracts out ISA behaviors. This change is a low level and pervasive reorganization of how PCs are managed in M5. Back when Alpha was the only ISA, there were only 2 PCs to worry about, the PC and the NPC, and the lsb of the PC signaled whether or not you were in PAL mode. As other ISAs were added, we had to add an NNPC, micro PC and next micropc, x86 and ARM introduced variable length instruction sets, and ARM started to keep track of mode bits in the PC. Each CPU model handled PCs in its own custom way that needed to be updated individually to handle the new dimensions of variability, or, in the case of ARMs mode-bit-in-the-pc hack, the complexity could be hidden in the ISA at the ISA implementation's expense. Areas like the branch predictor hadn't been updated to handle branch delay slots or micropcs, and it turns out that had introduced a significant (10s of percent) performance bug in SPARC and to a lesser extend MIPS. Rather than perpetuate the problem by reworking O3 again to handle the PC features needed by x86, this change was introduced to rework PC handling in a more modular, transparent, and hopefully efficient way. PC type: Rather than having the superset of all possible elements of PC state declared in each of the CPU models, each ISA defines its own PCState type which has exactly the elements it needs. A cross product of canned PCState classes are defined in the new "generic" ISA directory for ISAs with/without delay slots and microcode. These are either typedef-ed or subclassed by each ISA. To read or write this structure through a *Context, you use the new pcState() accessor which reads or writes depending on whether it has an argument. If you just want the address of the current or next instruction or the current micro PC, you can get those through read-only accessors on either the PCState type or the *Contexts. These are instAddr(), nextInstAddr(), and microPC(). Note the move away from readPC. That name is ambiguous since it's not clear whether or not it should be the actual address to fetch from, or if it should have extra bits in it like the PAL mode bit. Each class is free to define its own functions to get at whatever values it needs however it needs to to be used in ISA specific code. Eventually Alpha's PAL mode bit could be moved out of the PC and into a separate field like ARM. These types can be reset to a particular pc (where npc = pc + sizeof(MachInst), nnpc = npc + sizeof(MachInst), upc = 0, nupc = 1 as appropriate), printed, serialized, and compared. There is a branching() function which encapsulates code in the CPU models that checked if an instruction branched or not. Exactly what that means in the context of branch delay slots which can skip an instruction when not taken is ambiguous, and ideally this function and its uses can be eliminated. PCStates also generally know how to advance themselves in various ways depending on if they point at an instruction, a microop, or the last microop of a macroop. More on that later. Ideally, accessing all the PCs at once when setting them will improve performance of M5 even though more data needs to be moved around. This is because often all the PCs need to be manipulated together, and by getting them all at once you avoid multiple function calls. Also, the PCs of a particular thread will have spatial locality in the cache. Previously they were grouped by element in arrays which spread out accesses. Advancing the PC: The PCs were previously managed entirely by the CPU which had to know about PC semantics, try to figure out which dimension to increment the PC in, what to set NPC/NNPC, etc. These decisions are best left to the ISA in conjunction with the PC type itself. Because most of the information about how to increment the PC (mainly what type of instruction it refers to) is contained in the instruction object, a new advancePC virtual function was added to the StaticInst class. Subclasses provide an implementation that moves around the right element of the PC with a minimal amount of decision making. In ISAs like Alpha, the instructions always simply assign NPC to PC without having to worry about micropcs, nnpcs, etc. The added cost of a virtual function call should be outweighed by not having to figure out as much about what to do with the PCs and mucking around with the extra elements. One drawback of making the StaticInsts advance the PC is that you have to actually have one to advance the PC. This would, superficially, seem to require decoding an instruction before fetch could advance. This is, as far as I can tell, realistic. fetch would advance through memory addresses, not PCs, perhaps predicting new memory addresses using existing ones. More sophisticated decisions about control flow would be made later on, after the instruction was decoded, and handed back to fetch. If branching needs to happen, some amount of decoding needs to happen to see that it's a branch, what the target is, etc. This could get a little more complicated if that gets done by the predecoder, but I'm choosing to ignore that for now. Variable length instructions: To handle variable length instructions in x86 and ARM, the predecoder now takes in the current PC by reference to the getExtMachInst function. It can modify the PC however it needs to (by setting NPC to be the PC + instruction length, for instance). This could be improved since the CPU doesn't know if the PC was modified and always has to write it back. ISA parser: To support the new API, all PC related operand types were removed from the parser and replaced with a PCState type. There are two warts on this implementation. First, as with all the other operand types, the PCState still has to have a valid operand type even though it doesn't use it. Second, using syntax like PCS.npc(target) doesn't work for two reasons, this looks like the syntax for operand type overriding, and the parser can't figure out if you're reading or writing. Instructions that use the PCS operand (which I've consistently called it) need to first read it into a local variable, manipulate it, and then write it back out. Return address stack: The return address stack needed a little extra help because, in the presence of branch delay slots, it has to merge together elements of the return PC and the call PC. To handle that, a buildRetPC utility function was added. There are basically only two versions in all the ISAs, but it didn't seem short enough to put into the generic ISA directory. Also, the branch predictor code in O3 and InOrder were adjusted so that they always store the PC of the actual call instruction in the RAS, not the next PC. If the call instruction is a microop, the next PC refers to the next microop in the same macroop which is probably not desirable. The buildRetPC function advances the PC intelligently to the next macroop (in an ISA specific way) so that that case works. Change in stats: There were no change in stats except in MIPS and SPARC in the O3 model. MIPS runs in about 9% fewer ticks. SPARC runs with 30%-50% fewer ticks, which could likely be improved further by setting call/return instruction flags and taking advantage of the RAS. TODO: Add != operators to the PCState classes, defined trivially to be !(a==b). Smooth out places where PCs are split apart, passed around, and put back together later. I think this might happen in SPARC's fault code. Add ISA specific constructors that allow setting PC elements without calling a bunch of accessors. Try to eliminate the need for the branching() function. Factor out Alpha's PAL mode pc bit into a separate flag field, and eliminate places where it's blindly masked out or tested in the PC.
2010-10-31 08:07:20 +01:00
DPRINTF(Decode,"Inserting [sn:%lli] PC: %s into decode skidBuffer %i\n",
inst->seqNum, inst->pcState(), inst->threadNumber);
Check in of various updates to the CPU. Mainly adds in stats, improves branch prediction, and makes memory dependence work properly. SConscript: Added return address stack, tournament predictor. cpu/base_cpu.cc: Added debug break and print statements. cpu/base_dyn_inst.cc: cpu/base_dyn_inst.hh: Comment out possibly unneeded variables. cpu/beta_cpu/2bit_local_pred.cc: 2bit predictor no longer speculatively updates itself. cpu/beta_cpu/alpha_dyn_inst.hh: Comment formatting. cpu/beta_cpu/alpha_full_cpu.hh: Formatting cpu/beta_cpu/alpha_full_cpu_builder.cc: Added new parameters for branch predictors, and IQ parameters. cpu/beta_cpu/alpha_full_cpu_impl.hh: Register stats. cpu/beta_cpu/alpha_params.hh: Added parameters for IQ, branch predictors, and store sets. cpu/beta_cpu/bpred_unit.cc: Removed one class. cpu/beta_cpu/bpred_unit.hh: Add in RAS, stats. Changed branch predictor unit functionality so that it holds a history of past branches so it can update, and also hold a proper history of the RAS so it can be restored on branch mispredicts. cpu/beta_cpu/bpred_unit_impl.hh: Added in stats, history of branches, RAS. Now bpred unit actually modifies the instruction's predicted next PC. cpu/beta_cpu/btb.cc: Add in sanity checks. cpu/beta_cpu/comm.hh: Add in communication where needed, remove it where it's not. cpu/beta_cpu/commit.hh: cpu/beta_cpu/rename.hh: cpu/beta_cpu/rename_impl.hh: Add in stats. cpu/beta_cpu/commit_impl.hh: Stats, update what is sent back on branch mispredict. cpu/beta_cpu/cpu_policy.hh: Change the bpred unit being used. cpu/beta_cpu/decode.hh: cpu/beta_cpu/decode_impl.hh: Stats. cpu/beta_cpu/fetch.hh: Stats, change squash so it can handle squashes from decode differently than squashes from commit. cpu/beta_cpu/fetch_impl.hh: Add in stats. Change how a cache line is fetched. Update to work with caches. Also have separate functions for different behavior if squash is coming from decode vs commit. cpu/beta_cpu/free_list.hh: Remove some old comments. cpu/beta_cpu/full_cpu.cc: cpu/beta_cpu/full_cpu.hh: Added function to remove instructions from back of instruction list until a certain sequence number. cpu/beta_cpu/iew.hh: Stats, separate squashing behavior due to branches vs memory. cpu/beta_cpu/iew_impl.hh: Stats, separate squashing behavior for branches vs memory. cpu/beta_cpu/inst_queue.cc: Debug stuff cpu/beta_cpu/inst_queue.hh: Stats, change how mem dep unit works, debug stuff cpu/beta_cpu/inst_queue_impl.hh: Stats, change how mem dep unit works, debug stuff. Also add in parameters that used to be hardcoded. cpu/beta_cpu/mem_dep_unit.hh: cpu/beta_cpu/mem_dep_unit_impl.hh: Add in stats, change how memory dependence unit works. It now holds the memory instructions that are waiting for their memory dependences to resolve. It provides which instructions are ready directly to the IQ. cpu/beta_cpu/regfile.hh: Fix up sanity checks. cpu/beta_cpu/rename_map.cc: Fix loop variable type. cpu/beta_cpu/rob_impl.hh: Remove intermediate DynInstPtr cpu/beta_cpu/store_set.cc: Add in debugging statements. cpu/beta_cpu/store_set.hh: Reorder function arguments to match the rest of the calls. --HG-- extra : convert_revision : aabf9b1fecd1d743265dfc3b174d6159937c6f44
2004-10-22 00:02:36 +02:00
skidBuffer[tid].push(inst);
}
// @todo: Eventually need to enforce this by not letting a thread
// fetch past its skidbuffer
assert(skidBuffer[tid].size() <= skidBufferMax);
}
template<class Impl>
bool
DefaultDecode<Impl>::skidsEmpty()
{
list<ThreadID>::iterator threads = activeThreads->begin();
list<ThreadID>::iterator end = activeThreads->end();
while (threads != end) {
ThreadID tid = *threads++;
if (!skidBuffer[tid].empty())
return false;
}
return true;
}
template<class Impl>
void
DefaultDecode<Impl>::updateStatus()
{
bool any_unblocking = false;
list<ThreadID>::iterator threads = activeThreads->begin();
list<ThreadID>::iterator end = activeThreads->end();
while (threads != end) {
ThreadID tid = *threads++;
if (decodeStatus[tid] == Unblocking) {
any_unblocking = true;
break;
}
}
// Decode will have activity if it's unblocking.
if (any_unblocking) {
if (_status == Inactive) {
_status = Active;
DPRINTF(Activity, "Activating stage.\n");
Two updates that got combined into one ChangeSet accidentally. They're both pretty simple so they shouldn't cause any trouble. First: Rename FullCPU and its variants in the o3 directory to O3CPU to differentiate from the old model, and also to specify it's an out of order model. Second: Include build options for selecting the Checker to be used. These options make sure if the Checker is being used there is a CPU that supports it also being compiled. SConstruct: Add in option USE_CHECKER to allow for not compiling in checker code. The checker is enabled through this option instead of through the CPU_MODELS list. However it's still necessary to treat the Checker like a CPU model, so it is appended onto the CPU_MODELS list if enabled. configs/test/test.py: Name change for DetailedCPU to DetailedO3CPU. Also include option for max tick. src/base/traceflags.py: Add in O3CPU trace flag. src/cpu/SConscript: Rename AlphaFullCPU to AlphaO3CPU. Only include checker sources if they're necessary. Also add a list of CPUs that support the Checker, and only allow the Checker to be compiled in if one of those CPUs are also being included. src/cpu/base_dyn_inst.cc: src/cpu/base_dyn_inst.hh: Rename typedef to ImplCPU instead of FullCPU, to differentiate from the old FullCPU. src/cpu/cpu_models.py: src/cpu/o3/alpha_cpu.cc: src/cpu/o3/alpha_cpu.hh: src/cpu/o3/alpha_cpu_builder.cc: src/cpu/o3/alpha_cpu_impl.hh: Rename AlphaFullCPU to AlphaO3CPU to differentiate from old FullCPU model. src/cpu/o3/alpha_dyn_inst.hh: src/cpu/o3/alpha_dyn_inst_impl.hh: src/cpu/o3/alpha_impl.hh: src/cpu/o3/alpha_params.hh: src/cpu/o3/commit.hh: src/cpu/o3/cpu.hh: src/cpu/o3/decode.hh: src/cpu/o3/decode_impl.hh: src/cpu/o3/fetch.hh: src/cpu/o3/iew.hh: src/cpu/o3/iew_impl.hh: src/cpu/o3/inst_queue.hh: src/cpu/o3/lsq.hh: src/cpu/o3/lsq_impl.hh: src/cpu/o3/lsq_unit.hh: src/cpu/o3/regfile.hh: src/cpu/o3/rename.hh: src/cpu/o3/rename_impl.hh: src/cpu/o3/rob.hh: src/cpu/o3/rob_impl.hh: src/cpu/o3/thread_state.hh: src/python/m5/objects/AlphaO3CPU.py: Rename FullCPU to O3CPU to differentiate from old FullCPU model. src/cpu/o3/commit_impl.hh: src/cpu/o3/cpu.cc: src/cpu/o3/fetch_impl.hh: src/cpu/o3/lsq_unit_impl.hh: Rename FullCPU to O3CPU to differentiate from old FullCPU model. Also #ifdef the checker code so it doesn't need to be included if it's not selected. --HG-- rename : src/cpu/checker/o3_cpu_builder.cc => src/cpu/checker/o3_builder.cc rename : src/cpu/checker/cpu_builder.cc => src/cpu/checker/ozone_builder.cc rename : src/python/m5/objects/AlphaFullCPU.py => src/python/m5/objects/AlphaO3CPU.py extra : convert_revision : 86619baf257b8b7c8955efd447eba56e0d7acd6a
2006-06-16 23:08:47 +02:00
cpu->activateStage(O3CPU::DecodeIdx);
}
} else {
// If it's not unblocking, then decode will not have any internal
// activity. Switch it to inactive.
if (_status == Active) {
_status = Inactive;
DPRINTF(Activity, "Deactivating stage.\n");
Two updates that got combined into one ChangeSet accidentally. They're both pretty simple so they shouldn't cause any trouble. First: Rename FullCPU and its variants in the o3 directory to O3CPU to differentiate from the old model, and also to specify it's an out of order model. Second: Include build options for selecting the Checker to be used. These options make sure if the Checker is being used there is a CPU that supports it also being compiled. SConstruct: Add in option USE_CHECKER to allow for not compiling in checker code. The checker is enabled through this option instead of through the CPU_MODELS list. However it's still necessary to treat the Checker like a CPU model, so it is appended onto the CPU_MODELS list if enabled. configs/test/test.py: Name change for DetailedCPU to DetailedO3CPU. Also include option for max tick. src/base/traceflags.py: Add in O3CPU trace flag. src/cpu/SConscript: Rename AlphaFullCPU to AlphaO3CPU. Only include checker sources if they're necessary. Also add a list of CPUs that support the Checker, and only allow the Checker to be compiled in if one of those CPUs are also being included. src/cpu/base_dyn_inst.cc: src/cpu/base_dyn_inst.hh: Rename typedef to ImplCPU instead of FullCPU, to differentiate from the old FullCPU. src/cpu/cpu_models.py: src/cpu/o3/alpha_cpu.cc: src/cpu/o3/alpha_cpu.hh: src/cpu/o3/alpha_cpu_builder.cc: src/cpu/o3/alpha_cpu_impl.hh: Rename AlphaFullCPU to AlphaO3CPU to differentiate from old FullCPU model. src/cpu/o3/alpha_dyn_inst.hh: src/cpu/o3/alpha_dyn_inst_impl.hh: src/cpu/o3/alpha_impl.hh: src/cpu/o3/alpha_params.hh: src/cpu/o3/commit.hh: src/cpu/o3/cpu.hh: src/cpu/o3/decode.hh: src/cpu/o3/decode_impl.hh: src/cpu/o3/fetch.hh: src/cpu/o3/iew.hh: src/cpu/o3/iew_impl.hh: src/cpu/o3/inst_queue.hh: src/cpu/o3/lsq.hh: src/cpu/o3/lsq_impl.hh: src/cpu/o3/lsq_unit.hh: src/cpu/o3/regfile.hh: src/cpu/o3/rename.hh: src/cpu/o3/rename_impl.hh: src/cpu/o3/rob.hh: src/cpu/o3/rob_impl.hh: src/cpu/o3/thread_state.hh: src/python/m5/objects/AlphaO3CPU.py: Rename FullCPU to O3CPU to differentiate from old FullCPU model. src/cpu/o3/commit_impl.hh: src/cpu/o3/cpu.cc: src/cpu/o3/fetch_impl.hh: src/cpu/o3/lsq_unit_impl.hh: Rename FullCPU to O3CPU to differentiate from old FullCPU model. Also #ifdef the checker code so it doesn't need to be included if it's not selected. --HG-- rename : src/cpu/checker/o3_cpu_builder.cc => src/cpu/checker/o3_builder.cc rename : src/cpu/checker/cpu_builder.cc => src/cpu/checker/ozone_builder.cc rename : src/python/m5/objects/AlphaFullCPU.py => src/python/m5/objects/AlphaO3CPU.py extra : convert_revision : 86619baf257b8b7c8955efd447eba56e0d7acd6a
2006-06-16 23:08:47 +02:00
cpu->deactivateStage(O3CPU::DecodeIdx);
}
}
}
template <class Impl>
void
DefaultDecode<Impl>::sortInsts()
{
int insts_from_fetch = fromFetch->size;
#ifdef DEBUG
for (ThreadID tid = 0; tid < numThreads; tid++)
assert(insts[tid].empty());
#endif
for (int i = 0; i < insts_from_fetch; ++i) {
insts[fromFetch->insts[i]->threadNumber].push(fromFetch->insts[i]);
}
}
template<class Impl>
void
DefaultDecode<Impl>::readStallSignals(ThreadID tid)
{
if (fromRename->renameBlock[tid]) {
stalls[tid].rename = true;
}
if (fromRename->renameUnblock[tid]) {
assert(stalls[tid].rename);
stalls[tid].rename = false;
}
if (fromIEW->iewBlock[tid]) {
stalls[tid].iew = true;
}
if (fromIEW->iewUnblock[tid]) {
assert(stalls[tid].iew);
stalls[tid].iew = false;
}
if (fromCommit->commitBlock[tid]) {
stalls[tid].commit = true;
}
if (fromCommit->commitUnblock[tid]) {
assert(stalls[tid].commit);
stalls[tid].commit = false;
}
}
template <class Impl>
bool
DefaultDecode<Impl>::checkSignalsAndUpdate(ThreadID tid)
{
// Check if there's a squash signal, squash if there is.
// Check stall signals, block if necessary.
// If status was blocked
// Check if stall conditions have passed
// if so then go to unblocking
// If status was Squashing
// check if squashing is not high. Switch to running this cycle.
// Update the per thread stall statuses.
readStallSignals(tid);
// Check squash signals from commit.
if (fromCommit->commitInfo[tid].squash) {
DPRINTF(Decode, "[tid:%u]: Squashing instructions due to squash "
"from commit.\n", tid);
squash(tid);
return true;
}
// Check ROB squash signals from commit.
if (fromCommit->commitInfo[tid].robSquashing) {
DPRINTF(Decode, "[tid:%u]: ROB is still squashing.\n", tid);
// Continue to squash.
decodeStatus[tid] = Squashing;
return true;
}
if (checkStall(tid)) {
return block(tid);
}
if (decodeStatus[tid] == Blocked) {
DPRINTF(Decode, "[tid:%u]: Done blocking, switching to unblocking.\n",
tid);
decodeStatus[tid] = Unblocking;
unblock(tid);
return true;
}
if (decodeStatus[tid] == Squashing) {
// Switch status to running if decode isn't being told to block or
// squash this cycle.
DPRINTF(Decode, "[tid:%u]: Done squashing, switching to running.\n",
tid);
decodeStatus[tid] = Running;
return false;
}
// If we've reached this point, we have not gotten any signals that
// cause decode to change its status. Decode remains the same as before.
return false;
}
template<class Impl>
void
DefaultDecode<Impl>::tick()
{
wroteToTimeBuffer = false;
bool status_change = false;
toRenameIndex = 0;
list<ThreadID>::iterator threads = activeThreads->begin();
list<ThreadID>::iterator end = activeThreads->end();
sortInsts();
//Check stall and squash signals.
while (threads != end) {
ThreadID tid = *threads++;
DPRINTF(Decode,"Processing [tid:%i]\n",tid);
status_change = checkSignalsAndUpdate(tid) || status_change;
decode(status_change, tid);
}
if (status_change) {
updateStatus();
}
if (wroteToTimeBuffer) {
DPRINTF(Activity, "Activity this cycle.\n");
cpu->activityThisCycle();
}
}
template<class Impl>
void
DefaultDecode<Impl>::decode(bool &status_change, ThreadID tid)
{
// If status is Running or idle,
// call decodeInsts()
// If status is Unblocking,
// buffer any instructions coming from fetch
// continue trying to empty skid buffer
// check if stall conditions have passed
if (decodeStatus[tid] == Blocked) {
++decodeBlockedCycles;
} else if (decodeStatus[tid] == Squashing) {
++decodeSquashCycles;
}
// Decode should try to decode as many instructions as its bandwidth
// will allow, as long as it is not currently blocked.
if (decodeStatus[tid] == Running ||
decodeStatus[tid] == Idle) {
This changeset gets the MIPS ISA pretty much working in the O3CPU. It builds, runs, and gets very very close to completing the hello world succesfully but there are some minor quirks to iron out. Who would've known a DELAY SLOT introduces that much complexity?! arrgh! Anyways, a lot of this stuff had to do with my project at MIPS and me needing to know how I was going to get this working for the MIPS ISA. So I figured I would try to touch it up and throw it in here (I hate to introduce non-completely working components... ) src/arch/alpha/isa/mem.isa: spacing src/arch/mips/faults.cc: src/arch/mips/faults.hh: Gabe really authored this src/arch/mips/isa/decoder.isa: add StoreConditional Flag to instruction src/arch/mips/isa/formats/basic.isa: Steven really did this file src/arch/mips/isa/formats/branch.isa: fix bug for uncond/cond control src/arch/mips/isa/formats/mem.isa: Adjust O3CPU memory access to use new memory model interface. src/arch/mips/isa/formats/util.isa: update LoadStoreBase template src/arch/mips/isa_traits.cc: update SERIALIZE partially src/arch/mips/process.cc: src/arch/mips/process.hh: no need for this for NOW. ASID/Virtual addressing handles it src/arch/mips/regfile/misc_regfile.hh: add in clear() function and comments for future usage of special misc. regs src/cpu/base_dyn_inst.hh: add in nextNPC variable and supporting functions. add isCondDelaySlot function Update predTaken and mispredicted functions src/cpu/base_dyn_inst_impl.hh: init nextNPC src/cpu/o3/SConscript: add MIPS files to compile src/cpu/o3/alpha/thread_context.hh: no need for my name on this file src/cpu/o3/bpred_unit_impl.hh: Update RAS appropriately for MIPS src/cpu/o3/comm.hh: add some extra communication variables to aid in handling the delay slots src/cpu/o3/commit.hh: minor name fix for nextNPC functions. src/cpu/o3/commit_impl.hh: src/cpu/o3/decode_impl.hh: src/cpu/o3/fetch_impl.hh: src/cpu/o3/iew_impl.hh: src/cpu/o3/inst_queue_impl.hh: src/cpu/o3/rename_impl.hh: Fix necessary variables and functions for squashes with delay slots src/cpu/o3/cpu.cc: Update function interface ... adjust removeInstsNotInROB function to recognize delay slots insts src/cpu/o3/cpu.hh: update removeInstsNotInROB src/cpu/o3/decode.hh: declare necessary variables for handling delay slot src/cpu/o3/dyn_inst.hh: Add in MipsDynInst src/cpu/o3/fetch.hh: src/cpu/o3/iew.hh: src/cpu/o3/rename.hh: declare necessary variables and adjust functions for handling delay slot src/cpu/o3/inst_queue.hh: src/cpu/simple/base.cc: no need for my name here src/cpu/o3/isa_specific.hh: add in MIPS files src/cpu/o3/scoreboard.hh: dont include alpha specific isa traits! src/cpu/o3/thread_context.hh: no need for my name here, i just rearranged where the file goes src/cpu/static_inst.hh: add isCondDelaySlot function src/cpu/o3/mips/cpu.cc: src/cpu/o3/mips/cpu.hh: src/cpu/o3/mips/cpu_builder.cc: src/cpu/o3/mips/cpu_impl.hh: src/cpu/o3/mips/dyn_inst.cc: src/cpu/o3/mips/dyn_inst.hh: src/cpu/o3/mips/dyn_inst_impl.hh: src/cpu/o3/mips/impl.hh: src/cpu/o3/mips/params.hh: src/cpu/o3/mips/thread_context.cc: src/cpu/o3/mips/thread_context.hh: MIPS file for O3CPU...mirrors ALPHA definition --HG-- extra : convert_revision : 9bb199b4085903e49ffd5a4c8ac44d11460d988c
2006-07-23 19:39:42 +02:00
DPRINTF(Decode, "[tid:%u]: Not blocked, so attempting to run "
"stage.\n",tid);
decodeInsts(tid);
} else if (decodeStatus[tid] == Unblocking) {
// Make sure that the skid buffer has something in it if the
// status is unblocking.
assert(!skidsEmpty());
// If the status was unblocking, then instructions from the skid
// buffer were used. Remove those instructions and handle
// the rest of unblocking.
decodeInsts(tid);
if (fetchInstsValid()) {
// Add the current inputs to the skid buffer so they can be
// reprocessed when this stage unblocks.
skidInsert(tid);
}
status_change = unblock(tid) || status_change;
}
}
template <class Impl>
void
DefaultDecode<Impl>::decodeInsts(ThreadID tid)
{
// Instructions can come either from the skid buffer or the list of
// instructions coming from fetch, depending on decode's status.
int insts_available = decodeStatus[tid] == Unblocking ?
skidBuffer[tid].size() : insts[tid].size();
if (insts_available == 0) {
DPRINTF(Decode, "[tid:%u] Nothing to do, breaking out"
" early.\n",tid);
// Should I change the status to idle?
Check in of various updates to the CPU. Mainly adds in stats, improves branch prediction, and makes memory dependence work properly. SConscript: Added return address stack, tournament predictor. cpu/base_cpu.cc: Added debug break and print statements. cpu/base_dyn_inst.cc: cpu/base_dyn_inst.hh: Comment out possibly unneeded variables. cpu/beta_cpu/2bit_local_pred.cc: 2bit predictor no longer speculatively updates itself. cpu/beta_cpu/alpha_dyn_inst.hh: Comment formatting. cpu/beta_cpu/alpha_full_cpu.hh: Formatting cpu/beta_cpu/alpha_full_cpu_builder.cc: Added new parameters for branch predictors, and IQ parameters. cpu/beta_cpu/alpha_full_cpu_impl.hh: Register stats. cpu/beta_cpu/alpha_params.hh: Added parameters for IQ, branch predictors, and store sets. cpu/beta_cpu/bpred_unit.cc: Removed one class. cpu/beta_cpu/bpred_unit.hh: Add in RAS, stats. Changed branch predictor unit functionality so that it holds a history of past branches so it can update, and also hold a proper history of the RAS so it can be restored on branch mispredicts. cpu/beta_cpu/bpred_unit_impl.hh: Added in stats, history of branches, RAS. Now bpred unit actually modifies the instruction's predicted next PC. cpu/beta_cpu/btb.cc: Add in sanity checks. cpu/beta_cpu/comm.hh: Add in communication where needed, remove it where it's not. cpu/beta_cpu/commit.hh: cpu/beta_cpu/rename.hh: cpu/beta_cpu/rename_impl.hh: Add in stats. cpu/beta_cpu/commit_impl.hh: Stats, update what is sent back on branch mispredict. cpu/beta_cpu/cpu_policy.hh: Change the bpred unit being used. cpu/beta_cpu/decode.hh: cpu/beta_cpu/decode_impl.hh: Stats. cpu/beta_cpu/fetch.hh: Stats, change squash so it can handle squashes from decode differently than squashes from commit. cpu/beta_cpu/fetch_impl.hh: Add in stats. Change how a cache line is fetched. Update to work with caches. Also have separate functions for different behavior if squash is coming from decode vs commit. cpu/beta_cpu/free_list.hh: Remove some old comments. cpu/beta_cpu/full_cpu.cc: cpu/beta_cpu/full_cpu.hh: Added function to remove instructions from back of instruction list until a certain sequence number. cpu/beta_cpu/iew.hh: Stats, separate squashing behavior due to branches vs memory. cpu/beta_cpu/iew_impl.hh: Stats, separate squashing behavior for branches vs memory. cpu/beta_cpu/inst_queue.cc: Debug stuff cpu/beta_cpu/inst_queue.hh: Stats, change how mem dep unit works, debug stuff cpu/beta_cpu/inst_queue_impl.hh: Stats, change how mem dep unit works, debug stuff. Also add in parameters that used to be hardcoded. cpu/beta_cpu/mem_dep_unit.hh: cpu/beta_cpu/mem_dep_unit_impl.hh: Add in stats, change how memory dependence unit works. It now holds the memory instructions that are waiting for their memory dependences to resolve. It provides which instructions are ready directly to the IQ. cpu/beta_cpu/regfile.hh: Fix up sanity checks. cpu/beta_cpu/rename_map.cc: Fix loop variable type. cpu/beta_cpu/rob_impl.hh: Remove intermediate DynInstPtr cpu/beta_cpu/store_set.cc: Add in debugging statements. cpu/beta_cpu/store_set.hh: Reorder function arguments to match the rest of the calls. --HG-- extra : convert_revision : aabf9b1fecd1d743265dfc3b174d6159937c6f44
2004-10-22 00:02:36 +02:00
++decodeIdleCycles;
return;
} else if (decodeStatus[tid] == Unblocking) {
DPRINTF(Decode, "[tid:%u] Unblocking, removing insts from skid "
"buffer.\n",tid);
++decodeUnblockCycles;
} else if (decodeStatus[tid] == Running) {
++decodeRunCycles;
}
Update to make multiple instruction issue and different latencies work. Also change to ref counted DynInst. SConscript: Add branch predictor, BTB, load store queue, and storesets. arch/isa_parser.py: Specify the template parameter for AlphaDynInst base/traceflags.py: Add load store queue, store set, and mem dependence unit to the list of trace flags. cpu/base_dyn_inst.cc: Change formating, add in debug statement. cpu/base_dyn_inst.hh: Change DynInst to be RefCounted, add flag to clear whether or not this instruction can commit. This is likely to be removed in the future. cpu/beta_cpu/alpha_dyn_inst.cc: AlphaDynInst has been changed to be templated, so now this CC file is just used to force instantiations of AlphaDynInst. cpu/beta_cpu/alpha_dyn_inst.hh: Changed AlphaDynInst to be templated on Impl. Removed some unnecessary functions. cpu/beta_cpu/alpha_full_cpu.cc: AlphaFullCPU has been changed to be templated, so this CC file is now just used to force instantation of AlphaFullCPU. cpu/beta_cpu/alpha_full_cpu.hh: Change AlphaFullCPU to be templated on Impl. cpu/beta_cpu/alpha_impl.hh: Update it to reflect AlphaDynInst and AlphaFullCPU being templated on Impl. Also removed time buffers from here, as they are really a part of the CPU and are thus in the CPU policy now. cpu/beta_cpu/alpha_params.hh: Make AlphaSimpleParams inherit from the BaseFullCPU so that it doesn't need to specifically declare any parameters that are already in the BaseFullCPU. cpu/beta_cpu/comm.hh: Changed the structure of the time buffer communication structs. Now they include the size of the packet of instructions it is sending. Added some parameters to the backwards communication struct, mainly for squashing. cpu/beta_cpu/commit.hh: Update typenames to reflect change in location of time buffer structs. Update DynInst to DynInstPtr (it is refcounted now). cpu/beta_cpu/commit_impl.hh: Formatting changes mainly. Also sends back proper information on branch mispredicts so that the bpred unit can update itself. Updated behavior for non-speculative instructions (stores, any other non-spec instructions): once they reach the head of the ROB, the ROB signals back to the IQ that it can go ahead and issue the non-speculative instruction. The instruction itself is updated so that commit won't try to commit it again until it is done executing. cpu/beta_cpu/cpu_policy.hh: Added branch prediction unit, mem dependence prediction unit, load store queue. Moved time buffer structs from AlphaSimpleImpl to here. cpu/beta_cpu/decode.hh: Changed typedefs to reflect change in location of time buffer structs and also the change from DynInst to ref counted DynInstPtr. cpu/beta_cpu/decode_impl.hh: Continues to buffer instructions even while unblocking now. Changed how it loops through groups of instructions so it can properly block during the middle of a group of instructions. cpu/beta_cpu/fetch.hh: Changed typedefs to reflect change in location of time buffer structs and the change to ref counted DynInsts. Also added in branch brediction unit. cpu/beta_cpu/fetch_impl.hh: Add in branch prediction. Changed how fetch checks inputs and its current state to make for easier logic. cpu/beta_cpu/free_list.cc: Changed int regs and float regs to logically use one flat namespace. Future change will be moving them to a single scoreboard to conserve space. cpu/beta_cpu/free_list.hh: Mostly debugging statements. Might be removed for performance in future. cpu/beta_cpu/full_cpu.cc: Added in some debugging statements. Updated BaseFullCPU to take a params object. cpu/beta_cpu/full_cpu.hh: Added params class within BaseCPU that other param classes will be able to inherit from. Updated typedefs to reflect change in location of time buffer structs and ref counted DynInst. cpu/beta_cpu/iew.hh: Updated typedefs to reflect change in location of time buffer structs and use of ref counted DynInsts. cpu/beta_cpu/iew_impl.hh: Added in load store queue, updated iew to be able to execute non- speculative instructions, instead of having them execute in commit. cpu/beta_cpu/inst_queue.hh: Updated change to ref counted DynInsts. Changed inst queue to hold non-speculative instructions as well, which are issued only when commit signals backwards that a nonspeculative instruction is at the head of the ROB. cpu/beta_cpu/inst_queue_impl.hh: Updated to allow for non-speculative instructions to be in the inst queue. Also added some debug functions. cpu/beta_cpu/regfile.hh: Added debugging statements, changed formatting. cpu/beta_cpu/rename.hh: Updated typedefs, added some functions to clean up code. cpu/beta_cpu/rename_impl.hh: Moved some code into functions to make it easier to read. cpu/beta_cpu/rename_map.cc: Changed int and float reg behavior to use a single flat namespace. In the future, the rename maps can be combined to a single rename map to save space. cpu/beta_cpu/rename_map.hh: Added destructor. cpu/beta_cpu/rob.hh: Updated it with change from DynInst to ref counted DynInst. cpu/beta_cpu/rob_impl.hh: Formatting, updated to use ref counted DynInst. cpu/static_inst.hh: Updated forward declaration for AlphaDynInst now that it is templated. --HG-- extra : convert_revision : 1045f240ee9b6a4bd368e1806aca029ebbdc6dd3
2004-09-23 20:06:03 +02:00
DynInstPtr inst;
std::queue<DynInstPtr>
&insts_to_decode = decodeStatus[tid] == Unblocking ?
skidBuffer[tid] : insts[tid];
Update to make multiple instruction issue and different latencies work. Also change to ref counted DynInst. SConscript: Add branch predictor, BTB, load store queue, and storesets. arch/isa_parser.py: Specify the template parameter for AlphaDynInst base/traceflags.py: Add load store queue, store set, and mem dependence unit to the list of trace flags. cpu/base_dyn_inst.cc: Change formating, add in debug statement. cpu/base_dyn_inst.hh: Change DynInst to be RefCounted, add flag to clear whether or not this instruction can commit. This is likely to be removed in the future. cpu/beta_cpu/alpha_dyn_inst.cc: AlphaDynInst has been changed to be templated, so now this CC file is just used to force instantiations of AlphaDynInst. cpu/beta_cpu/alpha_dyn_inst.hh: Changed AlphaDynInst to be templated on Impl. Removed some unnecessary functions. cpu/beta_cpu/alpha_full_cpu.cc: AlphaFullCPU has been changed to be templated, so this CC file is now just used to force instantation of AlphaFullCPU. cpu/beta_cpu/alpha_full_cpu.hh: Change AlphaFullCPU to be templated on Impl. cpu/beta_cpu/alpha_impl.hh: Update it to reflect AlphaDynInst and AlphaFullCPU being templated on Impl. Also removed time buffers from here, as they are really a part of the CPU and are thus in the CPU policy now. cpu/beta_cpu/alpha_params.hh: Make AlphaSimpleParams inherit from the BaseFullCPU so that it doesn't need to specifically declare any parameters that are already in the BaseFullCPU. cpu/beta_cpu/comm.hh: Changed the structure of the time buffer communication structs. Now they include the size of the packet of instructions it is sending. Added some parameters to the backwards communication struct, mainly for squashing. cpu/beta_cpu/commit.hh: Update typenames to reflect change in location of time buffer structs. Update DynInst to DynInstPtr (it is refcounted now). cpu/beta_cpu/commit_impl.hh: Formatting changes mainly. Also sends back proper information on branch mispredicts so that the bpred unit can update itself. Updated behavior for non-speculative instructions (stores, any other non-spec instructions): once they reach the head of the ROB, the ROB signals back to the IQ that it can go ahead and issue the non-speculative instruction. The instruction itself is updated so that commit won't try to commit it again until it is done executing. cpu/beta_cpu/cpu_policy.hh: Added branch prediction unit, mem dependence prediction unit, load store queue. Moved time buffer structs from AlphaSimpleImpl to here. cpu/beta_cpu/decode.hh: Changed typedefs to reflect change in location of time buffer structs and also the change from DynInst to ref counted DynInstPtr. cpu/beta_cpu/decode_impl.hh: Continues to buffer instructions even while unblocking now. Changed how it loops through groups of instructions so it can properly block during the middle of a group of instructions. cpu/beta_cpu/fetch.hh: Changed typedefs to reflect change in location of time buffer structs and the change to ref counted DynInsts. Also added in branch brediction unit. cpu/beta_cpu/fetch_impl.hh: Add in branch prediction. Changed how fetch checks inputs and its current state to make for easier logic. cpu/beta_cpu/free_list.cc: Changed int regs and float regs to logically use one flat namespace. Future change will be moving them to a single scoreboard to conserve space. cpu/beta_cpu/free_list.hh: Mostly debugging statements. Might be removed for performance in future. cpu/beta_cpu/full_cpu.cc: Added in some debugging statements. Updated BaseFullCPU to take a params object. cpu/beta_cpu/full_cpu.hh: Added params class within BaseCPU that other param classes will be able to inherit from. Updated typedefs to reflect change in location of time buffer structs and ref counted DynInst. cpu/beta_cpu/iew.hh: Updated typedefs to reflect change in location of time buffer structs and use of ref counted DynInsts. cpu/beta_cpu/iew_impl.hh: Added in load store queue, updated iew to be able to execute non- speculative instructions, instead of having them execute in commit. cpu/beta_cpu/inst_queue.hh: Updated change to ref counted DynInsts. Changed inst queue to hold non-speculative instructions as well, which are issued only when commit signals backwards that a nonspeculative instruction is at the head of the ROB. cpu/beta_cpu/inst_queue_impl.hh: Updated to allow for non-speculative instructions to be in the inst queue. Also added some debug functions. cpu/beta_cpu/regfile.hh: Added debugging statements, changed formatting. cpu/beta_cpu/rename.hh: Updated typedefs, added some functions to clean up code. cpu/beta_cpu/rename_impl.hh: Moved some code into functions to make it easier to read. cpu/beta_cpu/rename_map.cc: Changed int and float reg behavior to use a single flat namespace. In the future, the rename maps can be combined to a single rename map to save space. cpu/beta_cpu/rename_map.hh: Added destructor. cpu/beta_cpu/rob.hh: Updated it with change from DynInst to ref counted DynInst. cpu/beta_cpu/rob_impl.hh: Formatting, updated to use ref counted DynInst. cpu/static_inst.hh: Updated forward declaration for AlphaDynInst now that it is templated. --HG-- extra : convert_revision : 1045f240ee9b6a4bd368e1806aca029ebbdc6dd3
2004-09-23 20:06:03 +02:00
DPRINTF(Decode, "[tid:%u]: Sending instruction to rename.\n",tid);
while (insts_available > 0 && toRenameIndex < decodeWidth) {
assert(!insts_to_decode.empty());
inst = insts_to_decode.front();
Check in of various updates to the CPU. Mainly adds in stats, improves branch prediction, and makes memory dependence work properly. SConscript: Added return address stack, tournament predictor. cpu/base_cpu.cc: Added debug break and print statements. cpu/base_dyn_inst.cc: cpu/base_dyn_inst.hh: Comment out possibly unneeded variables. cpu/beta_cpu/2bit_local_pred.cc: 2bit predictor no longer speculatively updates itself. cpu/beta_cpu/alpha_dyn_inst.hh: Comment formatting. cpu/beta_cpu/alpha_full_cpu.hh: Formatting cpu/beta_cpu/alpha_full_cpu_builder.cc: Added new parameters for branch predictors, and IQ parameters. cpu/beta_cpu/alpha_full_cpu_impl.hh: Register stats. cpu/beta_cpu/alpha_params.hh: Added parameters for IQ, branch predictors, and store sets. cpu/beta_cpu/bpred_unit.cc: Removed one class. cpu/beta_cpu/bpred_unit.hh: Add in RAS, stats. Changed branch predictor unit functionality so that it holds a history of past branches so it can update, and also hold a proper history of the RAS so it can be restored on branch mispredicts. cpu/beta_cpu/bpred_unit_impl.hh: Added in stats, history of branches, RAS. Now bpred unit actually modifies the instruction's predicted next PC. cpu/beta_cpu/btb.cc: Add in sanity checks. cpu/beta_cpu/comm.hh: Add in communication where needed, remove it where it's not. cpu/beta_cpu/commit.hh: cpu/beta_cpu/rename.hh: cpu/beta_cpu/rename_impl.hh: Add in stats. cpu/beta_cpu/commit_impl.hh: Stats, update what is sent back on branch mispredict. cpu/beta_cpu/cpu_policy.hh: Change the bpred unit being used. cpu/beta_cpu/decode.hh: cpu/beta_cpu/decode_impl.hh: Stats. cpu/beta_cpu/fetch.hh: Stats, change squash so it can handle squashes from decode differently than squashes from commit. cpu/beta_cpu/fetch_impl.hh: Add in stats. Change how a cache line is fetched. Update to work with caches. Also have separate functions for different behavior if squash is coming from decode vs commit. cpu/beta_cpu/free_list.hh: Remove some old comments. cpu/beta_cpu/full_cpu.cc: cpu/beta_cpu/full_cpu.hh: Added function to remove instructions from back of instruction list until a certain sequence number. cpu/beta_cpu/iew.hh: Stats, separate squashing behavior due to branches vs memory. cpu/beta_cpu/iew_impl.hh: Stats, separate squashing behavior for branches vs memory. cpu/beta_cpu/inst_queue.cc: Debug stuff cpu/beta_cpu/inst_queue.hh: Stats, change how mem dep unit works, debug stuff cpu/beta_cpu/inst_queue_impl.hh: Stats, change how mem dep unit works, debug stuff. Also add in parameters that used to be hardcoded. cpu/beta_cpu/mem_dep_unit.hh: cpu/beta_cpu/mem_dep_unit_impl.hh: Add in stats, change how memory dependence unit works. It now holds the memory instructions that are waiting for their memory dependences to resolve. It provides which instructions are ready directly to the IQ. cpu/beta_cpu/regfile.hh: Fix up sanity checks. cpu/beta_cpu/rename_map.cc: Fix loop variable type. cpu/beta_cpu/rob_impl.hh: Remove intermediate DynInstPtr cpu/beta_cpu/store_set.cc: Add in debugging statements. cpu/beta_cpu/store_set.hh: Reorder function arguments to match the rest of the calls. --HG-- extra : convert_revision : aabf9b1fecd1d743265dfc3b174d6159937c6f44
2004-10-22 00:02:36 +02:00
insts_to_decode.pop();
Update to make multiple instruction issue and different latencies work. Also change to ref counted DynInst. SConscript: Add branch predictor, BTB, load store queue, and storesets. arch/isa_parser.py: Specify the template parameter for AlphaDynInst base/traceflags.py: Add load store queue, store set, and mem dependence unit to the list of trace flags. cpu/base_dyn_inst.cc: Change formating, add in debug statement. cpu/base_dyn_inst.hh: Change DynInst to be RefCounted, add flag to clear whether or not this instruction can commit. This is likely to be removed in the future. cpu/beta_cpu/alpha_dyn_inst.cc: AlphaDynInst has been changed to be templated, so now this CC file is just used to force instantiations of AlphaDynInst. cpu/beta_cpu/alpha_dyn_inst.hh: Changed AlphaDynInst to be templated on Impl. Removed some unnecessary functions. cpu/beta_cpu/alpha_full_cpu.cc: AlphaFullCPU has been changed to be templated, so this CC file is now just used to force instantation of AlphaFullCPU. cpu/beta_cpu/alpha_full_cpu.hh: Change AlphaFullCPU to be templated on Impl. cpu/beta_cpu/alpha_impl.hh: Update it to reflect AlphaDynInst and AlphaFullCPU being templated on Impl. Also removed time buffers from here, as they are really a part of the CPU and are thus in the CPU policy now. cpu/beta_cpu/alpha_params.hh: Make AlphaSimpleParams inherit from the BaseFullCPU so that it doesn't need to specifically declare any parameters that are already in the BaseFullCPU. cpu/beta_cpu/comm.hh: Changed the structure of the time buffer communication structs. Now they include the size of the packet of instructions it is sending. Added some parameters to the backwards communication struct, mainly for squashing. cpu/beta_cpu/commit.hh: Update typenames to reflect change in location of time buffer structs. Update DynInst to DynInstPtr (it is refcounted now). cpu/beta_cpu/commit_impl.hh: Formatting changes mainly. Also sends back proper information on branch mispredicts so that the bpred unit can update itself. Updated behavior for non-speculative instructions (stores, any other non-spec instructions): once they reach the head of the ROB, the ROB signals back to the IQ that it can go ahead and issue the non-speculative instruction. The instruction itself is updated so that commit won't try to commit it again until it is done executing. cpu/beta_cpu/cpu_policy.hh: Added branch prediction unit, mem dependence prediction unit, load store queue. Moved time buffer structs from AlphaSimpleImpl to here. cpu/beta_cpu/decode.hh: Changed typedefs to reflect change in location of time buffer structs and also the change from DynInst to ref counted DynInstPtr. cpu/beta_cpu/decode_impl.hh: Continues to buffer instructions even while unblocking now. Changed how it loops through groups of instructions so it can properly block during the middle of a group of instructions. cpu/beta_cpu/fetch.hh: Changed typedefs to reflect change in location of time buffer structs and the change to ref counted DynInsts. Also added in branch brediction unit. cpu/beta_cpu/fetch_impl.hh: Add in branch prediction. Changed how fetch checks inputs and its current state to make for easier logic. cpu/beta_cpu/free_list.cc: Changed int regs and float regs to logically use one flat namespace. Future change will be moving them to a single scoreboard to conserve space. cpu/beta_cpu/free_list.hh: Mostly debugging statements. Might be removed for performance in future. cpu/beta_cpu/full_cpu.cc: Added in some debugging statements. Updated BaseFullCPU to take a params object. cpu/beta_cpu/full_cpu.hh: Added params class within BaseCPU that other param classes will be able to inherit from. Updated typedefs to reflect change in location of time buffer structs and ref counted DynInst. cpu/beta_cpu/iew.hh: Updated typedefs to reflect change in location of time buffer structs and use of ref counted DynInsts. cpu/beta_cpu/iew_impl.hh: Added in load store queue, updated iew to be able to execute non- speculative instructions, instead of having them execute in commit. cpu/beta_cpu/inst_queue.hh: Updated change to ref counted DynInsts. Changed inst queue to hold non-speculative instructions as well, which are issued only when commit signals backwards that a nonspeculative instruction is at the head of the ROB. cpu/beta_cpu/inst_queue_impl.hh: Updated to allow for non-speculative instructions to be in the inst queue. Also added some debug functions. cpu/beta_cpu/regfile.hh: Added debugging statements, changed formatting. cpu/beta_cpu/rename.hh: Updated typedefs, added some functions to clean up code. cpu/beta_cpu/rename_impl.hh: Moved some code into functions to make it easier to read. cpu/beta_cpu/rename_map.cc: Changed int and float reg behavior to use a single flat namespace. In the future, the rename maps can be combined to a single rename map to save space. cpu/beta_cpu/rename_map.hh: Added destructor. cpu/beta_cpu/rob.hh: Updated it with change from DynInst to ref counted DynInst. cpu/beta_cpu/rob_impl.hh: Formatting, updated to use ref counted DynInst. cpu/static_inst.hh: Updated forward declaration for AlphaDynInst now that it is templated. --HG-- extra : convert_revision : 1045f240ee9b6a4bd368e1806aca029ebbdc6dd3
2004-09-23 20:06:03 +02:00
DPRINTF(Decode, "[tid:%u]: Processing instruction [sn:%lli] with "
ISA,CPU,etc: Create an ISA defined PC type that abstracts out ISA behaviors. This change is a low level and pervasive reorganization of how PCs are managed in M5. Back when Alpha was the only ISA, there were only 2 PCs to worry about, the PC and the NPC, and the lsb of the PC signaled whether or not you were in PAL mode. As other ISAs were added, we had to add an NNPC, micro PC and next micropc, x86 and ARM introduced variable length instruction sets, and ARM started to keep track of mode bits in the PC. Each CPU model handled PCs in its own custom way that needed to be updated individually to handle the new dimensions of variability, or, in the case of ARMs mode-bit-in-the-pc hack, the complexity could be hidden in the ISA at the ISA implementation's expense. Areas like the branch predictor hadn't been updated to handle branch delay slots or micropcs, and it turns out that had introduced a significant (10s of percent) performance bug in SPARC and to a lesser extend MIPS. Rather than perpetuate the problem by reworking O3 again to handle the PC features needed by x86, this change was introduced to rework PC handling in a more modular, transparent, and hopefully efficient way. PC type: Rather than having the superset of all possible elements of PC state declared in each of the CPU models, each ISA defines its own PCState type which has exactly the elements it needs. A cross product of canned PCState classes are defined in the new "generic" ISA directory for ISAs with/without delay slots and microcode. These are either typedef-ed or subclassed by each ISA. To read or write this structure through a *Context, you use the new pcState() accessor which reads or writes depending on whether it has an argument. If you just want the address of the current or next instruction or the current micro PC, you can get those through read-only accessors on either the PCState type or the *Contexts. These are instAddr(), nextInstAddr(), and microPC(). Note the move away from readPC. That name is ambiguous since it's not clear whether or not it should be the actual address to fetch from, or if it should have extra bits in it like the PAL mode bit. Each class is free to define its own functions to get at whatever values it needs however it needs to to be used in ISA specific code. Eventually Alpha's PAL mode bit could be moved out of the PC and into a separate field like ARM. These types can be reset to a particular pc (where npc = pc + sizeof(MachInst), nnpc = npc + sizeof(MachInst), upc = 0, nupc = 1 as appropriate), printed, serialized, and compared. There is a branching() function which encapsulates code in the CPU models that checked if an instruction branched or not. Exactly what that means in the context of branch delay slots which can skip an instruction when not taken is ambiguous, and ideally this function and its uses can be eliminated. PCStates also generally know how to advance themselves in various ways depending on if they point at an instruction, a microop, or the last microop of a macroop. More on that later. Ideally, accessing all the PCs at once when setting them will improve performance of M5 even though more data needs to be moved around. This is because often all the PCs need to be manipulated together, and by getting them all at once you avoid multiple function calls. Also, the PCs of a particular thread will have spatial locality in the cache. Previously they were grouped by element in arrays which spread out accesses. Advancing the PC: The PCs were previously managed entirely by the CPU which had to know about PC semantics, try to figure out which dimension to increment the PC in, what to set NPC/NNPC, etc. These decisions are best left to the ISA in conjunction with the PC type itself. Because most of the information about how to increment the PC (mainly what type of instruction it refers to) is contained in the instruction object, a new advancePC virtual function was added to the StaticInst class. Subclasses provide an implementation that moves around the right element of the PC with a minimal amount of decision making. In ISAs like Alpha, the instructions always simply assign NPC to PC without having to worry about micropcs, nnpcs, etc. The added cost of a virtual function call should be outweighed by not having to figure out as much about what to do with the PCs and mucking around with the extra elements. One drawback of making the StaticInsts advance the PC is that you have to actually have one to advance the PC. This would, superficially, seem to require decoding an instruction before fetch could advance. This is, as far as I can tell, realistic. fetch would advance through memory addresses, not PCs, perhaps predicting new memory addresses using existing ones. More sophisticated decisions about control flow would be made later on, after the instruction was decoded, and handed back to fetch. If branching needs to happen, some amount of decoding needs to happen to see that it's a branch, what the target is, etc. This could get a little more complicated if that gets done by the predecoder, but I'm choosing to ignore that for now. Variable length instructions: To handle variable length instructions in x86 and ARM, the predecoder now takes in the current PC by reference to the getExtMachInst function. It can modify the PC however it needs to (by setting NPC to be the PC + instruction length, for instance). This could be improved since the CPU doesn't know if the PC was modified and always has to write it back. ISA parser: To support the new API, all PC related operand types were removed from the parser and replaced with a PCState type. There are two warts on this implementation. First, as with all the other operand types, the PCState still has to have a valid operand type even though it doesn't use it. Second, using syntax like PCS.npc(target) doesn't work for two reasons, this looks like the syntax for operand type overriding, and the parser can't figure out if you're reading or writing. Instructions that use the PCS operand (which I've consistently called it) need to first read it into a local variable, manipulate it, and then write it back out. Return address stack: The return address stack needed a little extra help because, in the presence of branch delay slots, it has to merge together elements of the return PC and the call PC. To handle that, a buildRetPC utility function was added. There are basically only two versions in all the ISAs, but it didn't seem short enough to put into the generic ISA directory. Also, the branch predictor code in O3 and InOrder were adjusted so that they always store the PC of the actual call instruction in the RAS, not the next PC. If the call instruction is a microop, the next PC refers to the next microop in the same macroop which is probably not desirable. The buildRetPC function advances the PC intelligently to the next macroop (in an ISA specific way) so that that case works. Change in stats: There were no change in stats except in MIPS and SPARC in the O3 model. MIPS runs in about 9% fewer ticks. SPARC runs with 30%-50% fewer ticks, which could likely be improved further by setting call/return instruction flags and taking advantage of the RAS. TODO: Add != operators to the PCState classes, defined trivially to be !(a==b). Smooth out places where PCs are split apart, passed around, and put back together later. I think this might happen in SPARC's fault code. Add ISA specific constructors that allow setting PC elements without calling a bunch of accessors. Try to eliminate the need for the branching() function. Factor out Alpha's PAL mode pc bit into a separate flag field, and eliminate places where it's blindly masked out or tested in the PC.
2010-10-31 08:07:20 +01:00
"PC %s\n", tid, inst->seqNum, inst->pcState());
Update to make multiple instruction issue and different latencies work. Also change to ref counted DynInst. SConscript: Add branch predictor, BTB, load store queue, and storesets. arch/isa_parser.py: Specify the template parameter for AlphaDynInst base/traceflags.py: Add load store queue, store set, and mem dependence unit to the list of trace flags. cpu/base_dyn_inst.cc: Change formating, add in debug statement. cpu/base_dyn_inst.hh: Change DynInst to be RefCounted, add flag to clear whether or not this instruction can commit. This is likely to be removed in the future. cpu/beta_cpu/alpha_dyn_inst.cc: AlphaDynInst has been changed to be templated, so now this CC file is just used to force instantiations of AlphaDynInst. cpu/beta_cpu/alpha_dyn_inst.hh: Changed AlphaDynInst to be templated on Impl. Removed some unnecessary functions. cpu/beta_cpu/alpha_full_cpu.cc: AlphaFullCPU has been changed to be templated, so this CC file is now just used to force instantation of AlphaFullCPU. cpu/beta_cpu/alpha_full_cpu.hh: Change AlphaFullCPU to be templated on Impl. cpu/beta_cpu/alpha_impl.hh: Update it to reflect AlphaDynInst and AlphaFullCPU being templated on Impl. Also removed time buffers from here, as they are really a part of the CPU and are thus in the CPU policy now. cpu/beta_cpu/alpha_params.hh: Make AlphaSimpleParams inherit from the BaseFullCPU so that it doesn't need to specifically declare any parameters that are already in the BaseFullCPU. cpu/beta_cpu/comm.hh: Changed the structure of the time buffer communication structs. Now they include the size of the packet of instructions it is sending. Added some parameters to the backwards communication struct, mainly for squashing. cpu/beta_cpu/commit.hh: Update typenames to reflect change in location of time buffer structs. Update DynInst to DynInstPtr (it is refcounted now). cpu/beta_cpu/commit_impl.hh: Formatting changes mainly. Also sends back proper information on branch mispredicts so that the bpred unit can update itself. Updated behavior for non-speculative instructions (stores, any other non-spec instructions): once they reach the head of the ROB, the ROB signals back to the IQ that it can go ahead and issue the non-speculative instruction. The instruction itself is updated so that commit won't try to commit it again until it is done executing. cpu/beta_cpu/cpu_policy.hh: Added branch prediction unit, mem dependence prediction unit, load store queue. Moved time buffer structs from AlphaSimpleImpl to here. cpu/beta_cpu/decode.hh: Changed typedefs to reflect change in location of time buffer structs and also the change from DynInst to ref counted DynInstPtr. cpu/beta_cpu/decode_impl.hh: Continues to buffer instructions even while unblocking now. Changed how it loops through groups of instructions so it can properly block during the middle of a group of instructions. cpu/beta_cpu/fetch.hh: Changed typedefs to reflect change in location of time buffer structs and the change to ref counted DynInsts. Also added in branch brediction unit. cpu/beta_cpu/fetch_impl.hh: Add in branch prediction. Changed how fetch checks inputs and its current state to make for easier logic. cpu/beta_cpu/free_list.cc: Changed int regs and float regs to logically use one flat namespace. Future change will be moving them to a single scoreboard to conserve space. cpu/beta_cpu/free_list.hh: Mostly debugging statements. Might be removed for performance in future. cpu/beta_cpu/full_cpu.cc: Added in some debugging statements. Updated BaseFullCPU to take a params object. cpu/beta_cpu/full_cpu.hh: Added params class within BaseCPU that other param classes will be able to inherit from. Updated typedefs to reflect change in location of time buffer structs and ref counted DynInst. cpu/beta_cpu/iew.hh: Updated typedefs to reflect change in location of time buffer structs and use of ref counted DynInsts. cpu/beta_cpu/iew_impl.hh: Added in load store queue, updated iew to be able to execute non- speculative instructions, instead of having them execute in commit. cpu/beta_cpu/inst_queue.hh: Updated change to ref counted DynInsts. Changed inst queue to hold non-speculative instructions as well, which are issued only when commit signals backwards that a nonspeculative instruction is at the head of the ROB. cpu/beta_cpu/inst_queue_impl.hh: Updated to allow for non-speculative instructions to be in the inst queue. Also added some debug functions. cpu/beta_cpu/regfile.hh: Added debugging statements, changed formatting. cpu/beta_cpu/rename.hh: Updated typedefs, added some functions to clean up code. cpu/beta_cpu/rename_impl.hh: Moved some code into functions to make it easier to read. cpu/beta_cpu/rename_map.cc: Changed int and float reg behavior to use a single flat namespace. In the future, the rename maps can be combined to a single rename map to save space. cpu/beta_cpu/rename_map.hh: Added destructor. cpu/beta_cpu/rob.hh: Updated it with change from DynInst to ref counted DynInst. cpu/beta_cpu/rob_impl.hh: Formatting, updated to use ref counted DynInst. cpu/static_inst.hh: Updated forward declaration for AlphaDynInst now that it is templated. --HG-- extra : convert_revision : 1045f240ee9b6a4bd368e1806aca029ebbdc6dd3
2004-09-23 20:06:03 +02:00
if (inst->isSquashed()) {
ISA,CPU,etc: Create an ISA defined PC type that abstracts out ISA behaviors. This change is a low level and pervasive reorganization of how PCs are managed in M5. Back when Alpha was the only ISA, there were only 2 PCs to worry about, the PC and the NPC, and the lsb of the PC signaled whether or not you were in PAL mode. As other ISAs were added, we had to add an NNPC, micro PC and next micropc, x86 and ARM introduced variable length instruction sets, and ARM started to keep track of mode bits in the PC. Each CPU model handled PCs in its own custom way that needed to be updated individually to handle the new dimensions of variability, or, in the case of ARMs mode-bit-in-the-pc hack, the complexity could be hidden in the ISA at the ISA implementation's expense. Areas like the branch predictor hadn't been updated to handle branch delay slots or micropcs, and it turns out that had introduced a significant (10s of percent) performance bug in SPARC and to a lesser extend MIPS. Rather than perpetuate the problem by reworking O3 again to handle the PC features needed by x86, this change was introduced to rework PC handling in a more modular, transparent, and hopefully efficient way. PC type: Rather than having the superset of all possible elements of PC state declared in each of the CPU models, each ISA defines its own PCState type which has exactly the elements it needs. A cross product of canned PCState classes are defined in the new "generic" ISA directory for ISAs with/without delay slots and microcode. These are either typedef-ed or subclassed by each ISA. To read or write this structure through a *Context, you use the new pcState() accessor which reads or writes depending on whether it has an argument. If you just want the address of the current or next instruction or the current micro PC, you can get those through read-only accessors on either the PCState type or the *Contexts. These are instAddr(), nextInstAddr(), and microPC(). Note the move away from readPC. That name is ambiguous since it's not clear whether or not it should be the actual address to fetch from, or if it should have extra bits in it like the PAL mode bit. Each class is free to define its own functions to get at whatever values it needs however it needs to to be used in ISA specific code. Eventually Alpha's PAL mode bit could be moved out of the PC and into a separate field like ARM. These types can be reset to a particular pc (where npc = pc + sizeof(MachInst), nnpc = npc + sizeof(MachInst), upc = 0, nupc = 1 as appropriate), printed, serialized, and compared. There is a branching() function which encapsulates code in the CPU models that checked if an instruction branched or not. Exactly what that means in the context of branch delay slots which can skip an instruction when not taken is ambiguous, and ideally this function and its uses can be eliminated. PCStates also generally know how to advance themselves in various ways depending on if they point at an instruction, a microop, or the last microop of a macroop. More on that later. Ideally, accessing all the PCs at once when setting them will improve performance of M5 even though more data needs to be moved around. This is because often all the PCs need to be manipulated together, and by getting them all at once you avoid multiple function calls. Also, the PCs of a particular thread will have spatial locality in the cache. Previously they were grouped by element in arrays which spread out accesses. Advancing the PC: The PCs were previously managed entirely by the CPU which had to know about PC semantics, try to figure out which dimension to increment the PC in, what to set NPC/NNPC, etc. These decisions are best left to the ISA in conjunction with the PC type itself. Because most of the information about how to increment the PC (mainly what type of instruction it refers to) is contained in the instruction object, a new advancePC virtual function was added to the StaticInst class. Subclasses provide an implementation that moves around the right element of the PC with a minimal amount of decision making. In ISAs like Alpha, the instructions always simply assign NPC to PC without having to worry about micropcs, nnpcs, etc. The added cost of a virtual function call should be outweighed by not having to figure out as much about what to do with the PCs and mucking around with the extra elements. One drawback of making the StaticInsts advance the PC is that you have to actually have one to advance the PC. This would, superficially, seem to require decoding an instruction before fetch could advance. This is, as far as I can tell, realistic. fetch would advance through memory addresses, not PCs, perhaps predicting new memory addresses using existing ones. More sophisticated decisions about control flow would be made later on, after the instruction was decoded, and handed back to fetch. If branching needs to happen, some amount of decoding needs to happen to see that it's a branch, what the target is, etc. This could get a little more complicated if that gets done by the predecoder, but I'm choosing to ignore that for now. Variable length instructions: To handle variable length instructions in x86 and ARM, the predecoder now takes in the current PC by reference to the getExtMachInst function. It can modify the PC however it needs to (by setting NPC to be the PC + instruction length, for instance). This could be improved since the CPU doesn't know if the PC was modified and always has to write it back. ISA parser: To support the new API, all PC related operand types were removed from the parser and replaced with a PCState type. There are two warts on this implementation. First, as with all the other operand types, the PCState still has to have a valid operand type even though it doesn't use it. Second, using syntax like PCS.npc(target) doesn't work for two reasons, this looks like the syntax for operand type overriding, and the parser can't figure out if you're reading or writing. Instructions that use the PCS operand (which I've consistently called it) need to first read it into a local variable, manipulate it, and then write it back out. Return address stack: The return address stack needed a little extra help because, in the presence of branch delay slots, it has to merge together elements of the return PC and the call PC. To handle that, a buildRetPC utility function was added. There are basically only two versions in all the ISAs, but it didn't seem short enough to put into the generic ISA directory. Also, the branch predictor code in O3 and InOrder were adjusted so that they always store the PC of the actual call instruction in the RAS, not the next PC. If the call instruction is a microop, the next PC refers to the next microop in the same macroop which is probably not desirable. The buildRetPC function advances the PC intelligently to the next macroop (in an ISA specific way) so that that case works. Change in stats: There were no change in stats except in MIPS and SPARC in the O3 model. MIPS runs in about 9% fewer ticks. SPARC runs with 30%-50% fewer ticks, which could likely be improved further by setting call/return instruction flags and taking advantage of the RAS. TODO: Add != operators to the PCState classes, defined trivially to be !(a==b). Smooth out places where PCs are split apart, passed around, and put back together later. I think this might happen in SPARC's fault code. Add ISA specific constructors that allow setting PC elements without calling a bunch of accessors. Try to eliminate the need for the branching() function. Factor out Alpha's PAL mode pc bit into a separate flag field, and eliminate places where it's blindly masked out or tested in the PC.
2010-10-31 08:07:20 +01:00
DPRINTF(Decode, "[tid:%u]: Instruction %i with PC %s is "
Update to make multiple instruction issue and different latencies work. Also change to ref counted DynInst. SConscript: Add branch predictor, BTB, load store queue, and storesets. arch/isa_parser.py: Specify the template parameter for AlphaDynInst base/traceflags.py: Add load store queue, store set, and mem dependence unit to the list of trace flags. cpu/base_dyn_inst.cc: Change formating, add in debug statement. cpu/base_dyn_inst.hh: Change DynInst to be RefCounted, add flag to clear whether or not this instruction can commit. This is likely to be removed in the future. cpu/beta_cpu/alpha_dyn_inst.cc: AlphaDynInst has been changed to be templated, so now this CC file is just used to force instantiations of AlphaDynInst. cpu/beta_cpu/alpha_dyn_inst.hh: Changed AlphaDynInst to be templated on Impl. Removed some unnecessary functions. cpu/beta_cpu/alpha_full_cpu.cc: AlphaFullCPU has been changed to be templated, so this CC file is now just used to force instantation of AlphaFullCPU. cpu/beta_cpu/alpha_full_cpu.hh: Change AlphaFullCPU to be templated on Impl. cpu/beta_cpu/alpha_impl.hh: Update it to reflect AlphaDynInst and AlphaFullCPU being templated on Impl. Also removed time buffers from here, as they are really a part of the CPU and are thus in the CPU policy now. cpu/beta_cpu/alpha_params.hh: Make AlphaSimpleParams inherit from the BaseFullCPU so that it doesn't need to specifically declare any parameters that are already in the BaseFullCPU. cpu/beta_cpu/comm.hh: Changed the structure of the time buffer communication structs. Now they include the size of the packet of instructions it is sending. Added some parameters to the backwards communication struct, mainly for squashing. cpu/beta_cpu/commit.hh: Update typenames to reflect change in location of time buffer structs. Update DynInst to DynInstPtr (it is refcounted now). cpu/beta_cpu/commit_impl.hh: Formatting changes mainly. Also sends back proper information on branch mispredicts so that the bpred unit can update itself. Updated behavior for non-speculative instructions (stores, any other non-spec instructions): once they reach the head of the ROB, the ROB signals back to the IQ that it can go ahead and issue the non-speculative instruction. The instruction itself is updated so that commit won't try to commit it again until it is done executing. cpu/beta_cpu/cpu_policy.hh: Added branch prediction unit, mem dependence prediction unit, load store queue. Moved time buffer structs from AlphaSimpleImpl to here. cpu/beta_cpu/decode.hh: Changed typedefs to reflect change in location of time buffer structs and also the change from DynInst to ref counted DynInstPtr. cpu/beta_cpu/decode_impl.hh: Continues to buffer instructions even while unblocking now. Changed how it loops through groups of instructions so it can properly block during the middle of a group of instructions. cpu/beta_cpu/fetch.hh: Changed typedefs to reflect change in location of time buffer structs and the change to ref counted DynInsts. Also added in branch brediction unit. cpu/beta_cpu/fetch_impl.hh: Add in branch prediction. Changed how fetch checks inputs and its current state to make for easier logic. cpu/beta_cpu/free_list.cc: Changed int regs and float regs to logically use one flat namespace. Future change will be moving them to a single scoreboard to conserve space. cpu/beta_cpu/free_list.hh: Mostly debugging statements. Might be removed for performance in future. cpu/beta_cpu/full_cpu.cc: Added in some debugging statements. Updated BaseFullCPU to take a params object. cpu/beta_cpu/full_cpu.hh: Added params class within BaseCPU that other param classes will be able to inherit from. Updated typedefs to reflect change in location of time buffer structs and ref counted DynInst. cpu/beta_cpu/iew.hh: Updated typedefs to reflect change in location of time buffer structs and use of ref counted DynInsts. cpu/beta_cpu/iew_impl.hh: Added in load store queue, updated iew to be able to execute non- speculative instructions, instead of having them execute in commit. cpu/beta_cpu/inst_queue.hh: Updated change to ref counted DynInsts. Changed inst queue to hold non-speculative instructions as well, which are issued only when commit signals backwards that a nonspeculative instruction is at the head of the ROB. cpu/beta_cpu/inst_queue_impl.hh: Updated to allow for non-speculative instructions to be in the inst queue. Also added some debug functions. cpu/beta_cpu/regfile.hh: Added debugging statements, changed formatting. cpu/beta_cpu/rename.hh: Updated typedefs, added some functions to clean up code. cpu/beta_cpu/rename_impl.hh: Moved some code into functions to make it easier to read. cpu/beta_cpu/rename_map.cc: Changed int and float reg behavior to use a single flat namespace. In the future, the rename maps can be combined to a single rename map to save space. cpu/beta_cpu/rename_map.hh: Added destructor. cpu/beta_cpu/rob.hh: Updated it with change from DynInst to ref counted DynInst. cpu/beta_cpu/rob_impl.hh: Formatting, updated to use ref counted DynInst. cpu/static_inst.hh: Updated forward declaration for AlphaDynInst now that it is templated. --HG-- extra : convert_revision : 1045f240ee9b6a4bd368e1806aca029ebbdc6dd3
2004-09-23 20:06:03 +02:00
"squashed, skipping.\n",
ISA,CPU,etc: Create an ISA defined PC type that abstracts out ISA behaviors. This change is a low level and pervasive reorganization of how PCs are managed in M5. Back when Alpha was the only ISA, there were only 2 PCs to worry about, the PC and the NPC, and the lsb of the PC signaled whether or not you were in PAL mode. As other ISAs were added, we had to add an NNPC, micro PC and next micropc, x86 and ARM introduced variable length instruction sets, and ARM started to keep track of mode bits in the PC. Each CPU model handled PCs in its own custom way that needed to be updated individually to handle the new dimensions of variability, or, in the case of ARMs mode-bit-in-the-pc hack, the complexity could be hidden in the ISA at the ISA implementation's expense. Areas like the branch predictor hadn't been updated to handle branch delay slots or micropcs, and it turns out that had introduced a significant (10s of percent) performance bug in SPARC and to a lesser extend MIPS. Rather than perpetuate the problem by reworking O3 again to handle the PC features needed by x86, this change was introduced to rework PC handling in a more modular, transparent, and hopefully efficient way. PC type: Rather than having the superset of all possible elements of PC state declared in each of the CPU models, each ISA defines its own PCState type which has exactly the elements it needs. A cross product of canned PCState classes are defined in the new "generic" ISA directory for ISAs with/without delay slots and microcode. These are either typedef-ed or subclassed by each ISA. To read or write this structure through a *Context, you use the new pcState() accessor which reads or writes depending on whether it has an argument. If you just want the address of the current or next instruction or the current micro PC, you can get those through read-only accessors on either the PCState type or the *Contexts. These are instAddr(), nextInstAddr(), and microPC(). Note the move away from readPC. That name is ambiguous since it's not clear whether or not it should be the actual address to fetch from, or if it should have extra bits in it like the PAL mode bit. Each class is free to define its own functions to get at whatever values it needs however it needs to to be used in ISA specific code. Eventually Alpha's PAL mode bit could be moved out of the PC and into a separate field like ARM. These types can be reset to a particular pc (where npc = pc + sizeof(MachInst), nnpc = npc + sizeof(MachInst), upc = 0, nupc = 1 as appropriate), printed, serialized, and compared. There is a branching() function which encapsulates code in the CPU models that checked if an instruction branched or not. Exactly what that means in the context of branch delay slots which can skip an instruction when not taken is ambiguous, and ideally this function and its uses can be eliminated. PCStates also generally know how to advance themselves in various ways depending on if they point at an instruction, a microop, or the last microop of a macroop. More on that later. Ideally, accessing all the PCs at once when setting them will improve performance of M5 even though more data needs to be moved around. This is because often all the PCs need to be manipulated together, and by getting them all at once you avoid multiple function calls. Also, the PCs of a particular thread will have spatial locality in the cache. Previously they were grouped by element in arrays which spread out accesses. Advancing the PC: The PCs were previously managed entirely by the CPU which had to know about PC semantics, try to figure out which dimension to increment the PC in, what to set NPC/NNPC, etc. These decisions are best left to the ISA in conjunction with the PC type itself. Because most of the information about how to increment the PC (mainly what type of instruction it refers to) is contained in the instruction object, a new advancePC virtual function was added to the StaticInst class. Subclasses provide an implementation that moves around the right element of the PC with a minimal amount of decision making. In ISAs like Alpha, the instructions always simply assign NPC to PC without having to worry about micropcs, nnpcs, etc. The added cost of a virtual function call should be outweighed by not having to figure out as much about what to do with the PCs and mucking around with the extra elements. One drawback of making the StaticInsts advance the PC is that you have to actually have one to advance the PC. This would, superficially, seem to require decoding an instruction before fetch could advance. This is, as far as I can tell, realistic. fetch would advance through memory addresses, not PCs, perhaps predicting new memory addresses using existing ones. More sophisticated decisions about control flow would be made later on, after the instruction was decoded, and handed back to fetch. If branching needs to happen, some amount of decoding needs to happen to see that it's a branch, what the target is, etc. This could get a little more complicated if that gets done by the predecoder, but I'm choosing to ignore that for now. Variable length instructions: To handle variable length instructions in x86 and ARM, the predecoder now takes in the current PC by reference to the getExtMachInst function. It can modify the PC however it needs to (by setting NPC to be the PC + instruction length, for instance). This could be improved since the CPU doesn't know if the PC was modified and always has to write it back. ISA parser: To support the new API, all PC related operand types were removed from the parser and replaced with a PCState type. There are two warts on this implementation. First, as with all the other operand types, the PCState still has to have a valid operand type even though it doesn't use it. Second, using syntax like PCS.npc(target) doesn't work for two reasons, this looks like the syntax for operand type overriding, and the parser can't figure out if you're reading or writing. Instructions that use the PCS operand (which I've consistently called it) need to first read it into a local variable, manipulate it, and then write it back out. Return address stack: The return address stack needed a little extra help because, in the presence of branch delay slots, it has to merge together elements of the return PC and the call PC. To handle that, a buildRetPC utility function was added. There are basically only two versions in all the ISAs, but it didn't seem short enough to put into the generic ISA directory. Also, the branch predictor code in O3 and InOrder were adjusted so that they always store the PC of the actual call instruction in the RAS, not the next PC. If the call instruction is a microop, the next PC refers to the next microop in the same macroop which is probably not desirable. The buildRetPC function advances the PC intelligently to the next macroop (in an ISA specific way) so that that case works. Change in stats: There were no change in stats except in MIPS and SPARC in the O3 model. MIPS runs in about 9% fewer ticks. SPARC runs with 30%-50% fewer ticks, which could likely be improved further by setting call/return instruction flags and taking advantage of the RAS. TODO: Add != operators to the PCState classes, defined trivially to be !(a==b). Smooth out places where PCs are split apart, passed around, and put back together later. I think this might happen in SPARC's fault code. Add ISA specific constructors that allow setting PC elements without calling a bunch of accessors. Try to eliminate the need for the branching() function. Factor out Alpha's PAL mode pc bit into a separate flag field, and eliminate places where it's blindly masked out or tested in the PC.
2010-10-31 08:07:20 +01:00
tid, inst->seqNum, inst->pcState());
Update to make multiple instruction issue and different latencies work. Also change to ref counted DynInst. SConscript: Add branch predictor, BTB, load store queue, and storesets. arch/isa_parser.py: Specify the template parameter for AlphaDynInst base/traceflags.py: Add load store queue, store set, and mem dependence unit to the list of trace flags. cpu/base_dyn_inst.cc: Change formating, add in debug statement. cpu/base_dyn_inst.hh: Change DynInst to be RefCounted, add flag to clear whether or not this instruction can commit. This is likely to be removed in the future. cpu/beta_cpu/alpha_dyn_inst.cc: AlphaDynInst has been changed to be templated, so now this CC file is just used to force instantiations of AlphaDynInst. cpu/beta_cpu/alpha_dyn_inst.hh: Changed AlphaDynInst to be templated on Impl. Removed some unnecessary functions. cpu/beta_cpu/alpha_full_cpu.cc: AlphaFullCPU has been changed to be templated, so this CC file is now just used to force instantation of AlphaFullCPU. cpu/beta_cpu/alpha_full_cpu.hh: Change AlphaFullCPU to be templated on Impl. cpu/beta_cpu/alpha_impl.hh: Update it to reflect AlphaDynInst and AlphaFullCPU being templated on Impl. Also removed time buffers from here, as they are really a part of the CPU and are thus in the CPU policy now. cpu/beta_cpu/alpha_params.hh: Make AlphaSimpleParams inherit from the BaseFullCPU so that it doesn't need to specifically declare any parameters that are already in the BaseFullCPU. cpu/beta_cpu/comm.hh: Changed the structure of the time buffer communication structs. Now they include the size of the packet of instructions it is sending. Added some parameters to the backwards communication struct, mainly for squashing. cpu/beta_cpu/commit.hh: Update typenames to reflect change in location of time buffer structs. Update DynInst to DynInstPtr (it is refcounted now). cpu/beta_cpu/commit_impl.hh: Formatting changes mainly. Also sends back proper information on branch mispredicts so that the bpred unit can update itself. Updated behavior for non-speculative instructions (stores, any other non-spec instructions): once they reach the head of the ROB, the ROB signals back to the IQ that it can go ahead and issue the non-speculative instruction. The instruction itself is updated so that commit won't try to commit it again until it is done executing. cpu/beta_cpu/cpu_policy.hh: Added branch prediction unit, mem dependence prediction unit, load store queue. Moved time buffer structs from AlphaSimpleImpl to here. cpu/beta_cpu/decode.hh: Changed typedefs to reflect change in location of time buffer structs and also the change from DynInst to ref counted DynInstPtr. cpu/beta_cpu/decode_impl.hh: Continues to buffer instructions even while unblocking now. Changed how it loops through groups of instructions so it can properly block during the middle of a group of instructions. cpu/beta_cpu/fetch.hh: Changed typedefs to reflect change in location of time buffer structs and the change to ref counted DynInsts. Also added in branch brediction unit. cpu/beta_cpu/fetch_impl.hh: Add in branch prediction. Changed how fetch checks inputs and its current state to make for easier logic. cpu/beta_cpu/free_list.cc: Changed int regs and float regs to logically use one flat namespace. Future change will be moving them to a single scoreboard to conserve space. cpu/beta_cpu/free_list.hh: Mostly debugging statements. Might be removed for performance in future. cpu/beta_cpu/full_cpu.cc: Added in some debugging statements. Updated BaseFullCPU to take a params object. cpu/beta_cpu/full_cpu.hh: Added params class within BaseCPU that other param classes will be able to inherit from. Updated typedefs to reflect change in location of time buffer structs and ref counted DynInst. cpu/beta_cpu/iew.hh: Updated typedefs to reflect change in location of time buffer structs and use of ref counted DynInsts. cpu/beta_cpu/iew_impl.hh: Added in load store queue, updated iew to be able to execute non- speculative instructions, instead of having them execute in commit. cpu/beta_cpu/inst_queue.hh: Updated change to ref counted DynInsts. Changed inst queue to hold non-speculative instructions as well, which are issued only when commit signals backwards that a nonspeculative instruction is at the head of the ROB. cpu/beta_cpu/inst_queue_impl.hh: Updated to allow for non-speculative instructions to be in the inst queue. Also added some debug functions. cpu/beta_cpu/regfile.hh: Added debugging statements, changed formatting. cpu/beta_cpu/rename.hh: Updated typedefs, added some functions to clean up code. cpu/beta_cpu/rename_impl.hh: Moved some code into functions to make it easier to read. cpu/beta_cpu/rename_map.cc: Changed int and float reg behavior to use a single flat namespace. In the future, the rename maps can be combined to a single rename map to save space. cpu/beta_cpu/rename_map.hh: Added destructor. cpu/beta_cpu/rob.hh: Updated it with change from DynInst to ref counted DynInst. cpu/beta_cpu/rob_impl.hh: Formatting, updated to use ref counted DynInst. cpu/static_inst.hh: Updated forward declaration for AlphaDynInst now that it is templated. --HG-- extra : convert_revision : 1045f240ee9b6a4bd368e1806aca029ebbdc6dd3
2004-09-23 20:06:03 +02:00
Check in of various updates to the CPU. Mainly adds in stats, improves branch prediction, and makes memory dependence work properly. SConscript: Added return address stack, tournament predictor. cpu/base_cpu.cc: Added debug break and print statements. cpu/base_dyn_inst.cc: cpu/base_dyn_inst.hh: Comment out possibly unneeded variables. cpu/beta_cpu/2bit_local_pred.cc: 2bit predictor no longer speculatively updates itself. cpu/beta_cpu/alpha_dyn_inst.hh: Comment formatting. cpu/beta_cpu/alpha_full_cpu.hh: Formatting cpu/beta_cpu/alpha_full_cpu_builder.cc: Added new parameters for branch predictors, and IQ parameters. cpu/beta_cpu/alpha_full_cpu_impl.hh: Register stats. cpu/beta_cpu/alpha_params.hh: Added parameters for IQ, branch predictors, and store sets. cpu/beta_cpu/bpred_unit.cc: Removed one class. cpu/beta_cpu/bpred_unit.hh: Add in RAS, stats. Changed branch predictor unit functionality so that it holds a history of past branches so it can update, and also hold a proper history of the RAS so it can be restored on branch mispredicts. cpu/beta_cpu/bpred_unit_impl.hh: Added in stats, history of branches, RAS. Now bpred unit actually modifies the instruction's predicted next PC. cpu/beta_cpu/btb.cc: Add in sanity checks. cpu/beta_cpu/comm.hh: Add in communication where needed, remove it where it's not. cpu/beta_cpu/commit.hh: cpu/beta_cpu/rename.hh: cpu/beta_cpu/rename_impl.hh: Add in stats. cpu/beta_cpu/commit_impl.hh: Stats, update what is sent back on branch mispredict. cpu/beta_cpu/cpu_policy.hh: Change the bpred unit being used. cpu/beta_cpu/decode.hh: cpu/beta_cpu/decode_impl.hh: Stats. cpu/beta_cpu/fetch.hh: Stats, change squash so it can handle squashes from decode differently than squashes from commit. cpu/beta_cpu/fetch_impl.hh: Add in stats. Change how a cache line is fetched. Update to work with caches. Also have separate functions for different behavior if squash is coming from decode vs commit. cpu/beta_cpu/free_list.hh: Remove some old comments. cpu/beta_cpu/full_cpu.cc: cpu/beta_cpu/full_cpu.hh: Added function to remove instructions from back of instruction list until a certain sequence number. cpu/beta_cpu/iew.hh: Stats, separate squashing behavior due to branches vs memory. cpu/beta_cpu/iew_impl.hh: Stats, separate squashing behavior for branches vs memory. cpu/beta_cpu/inst_queue.cc: Debug stuff cpu/beta_cpu/inst_queue.hh: Stats, change how mem dep unit works, debug stuff cpu/beta_cpu/inst_queue_impl.hh: Stats, change how mem dep unit works, debug stuff. Also add in parameters that used to be hardcoded. cpu/beta_cpu/mem_dep_unit.hh: cpu/beta_cpu/mem_dep_unit_impl.hh: Add in stats, change how memory dependence unit works. It now holds the memory instructions that are waiting for their memory dependences to resolve. It provides which instructions are ready directly to the IQ. cpu/beta_cpu/regfile.hh: Fix up sanity checks. cpu/beta_cpu/rename_map.cc: Fix loop variable type. cpu/beta_cpu/rob_impl.hh: Remove intermediate DynInstPtr cpu/beta_cpu/store_set.cc: Add in debugging statements. cpu/beta_cpu/store_set.hh: Reorder function arguments to match the rest of the calls. --HG-- extra : convert_revision : aabf9b1fecd1d743265dfc3b174d6159937c6f44
2004-10-22 00:02:36 +02:00
++decodeSquashedInsts;
Update to make multiple instruction issue and different latencies work. Also change to ref counted DynInst. SConscript: Add branch predictor, BTB, load store queue, and storesets. arch/isa_parser.py: Specify the template parameter for AlphaDynInst base/traceflags.py: Add load store queue, store set, and mem dependence unit to the list of trace flags. cpu/base_dyn_inst.cc: Change formating, add in debug statement. cpu/base_dyn_inst.hh: Change DynInst to be RefCounted, add flag to clear whether or not this instruction can commit. This is likely to be removed in the future. cpu/beta_cpu/alpha_dyn_inst.cc: AlphaDynInst has been changed to be templated, so now this CC file is just used to force instantiations of AlphaDynInst. cpu/beta_cpu/alpha_dyn_inst.hh: Changed AlphaDynInst to be templated on Impl. Removed some unnecessary functions. cpu/beta_cpu/alpha_full_cpu.cc: AlphaFullCPU has been changed to be templated, so this CC file is now just used to force instantation of AlphaFullCPU. cpu/beta_cpu/alpha_full_cpu.hh: Change AlphaFullCPU to be templated on Impl. cpu/beta_cpu/alpha_impl.hh: Update it to reflect AlphaDynInst and AlphaFullCPU being templated on Impl. Also removed time buffers from here, as they are really a part of the CPU and are thus in the CPU policy now. cpu/beta_cpu/alpha_params.hh: Make AlphaSimpleParams inherit from the BaseFullCPU so that it doesn't need to specifically declare any parameters that are already in the BaseFullCPU. cpu/beta_cpu/comm.hh: Changed the structure of the time buffer communication structs. Now they include the size of the packet of instructions it is sending. Added some parameters to the backwards communication struct, mainly for squashing. cpu/beta_cpu/commit.hh: Update typenames to reflect change in location of time buffer structs. Update DynInst to DynInstPtr (it is refcounted now). cpu/beta_cpu/commit_impl.hh: Formatting changes mainly. Also sends back proper information on branch mispredicts so that the bpred unit can update itself. Updated behavior for non-speculative instructions (stores, any other non-spec instructions): once they reach the head of the ROB, the ROB signals back to the IQ that it can go ahead and issue the non-speculative instruction. The instruction itself is updated so that commit won't try to commit it again until it is done executing. cpu/beta_cpu/cpu_policy.hh: Added branch prediction unit, mem dependence prediction unit, load store queue. Moved time buffer structs from AlphaSimpleImpl to here. cpu/beta_cpu/decode.hh: Changed typedefs to reflect change in location of time buffer structs and also the change from DynInst to ref counted DynInstPtr. cpu/beta_cpu/decode_impl.hh: Continues to buffer instructions even while unblocking now. Changed how it loops through groups of instructions so it can properly block during the middle of a group of instructions. cpu/beta_cpu/fetch.hh: Changed typedefs to reflect change in location of time buffer structs and the change to ref counted DynInsts. Also added in branch brediction unit. cpu/beta_cpu/fetch_impl.hh: Add in branch prediction. Changed how fetch checks inputs and its current state to make for easier logic. cpu/beta_cpu/free_list.cc: Changed int regs and float regs to logically use one flat namespace. Future change will be moving them to a single scoreboard to conserve space. cpu/beta_cpu/free_list.hh: Mostly debugging statements. Might be removed for performance in future. cpu/beta_cpu/full_cpu.cc: Added in some debugging statements. Updated BaseFullCPU to take a params object. cpu/beta_cpu/full_cpu.hh: Added params class within BaseCPU that other param classes will be able to inherit from. Updated typedefs to reflect change in location of time buffer structs and ref counted DynInst. cpu/beta_cpu/iew.hh: Updated typedefs to reflect change in location of time buffer structs and use of ref counted DynInsts. cpu/beta_cpu/iew_impl.hh: Added in load store queue, updated iew to be able to execute non- speculative instructions, instead of having them execute in commit. cpu/beta_cpu/inst_queue.hh: Updated change to ref counted DynInsts. Changed inst queue to hold non-speculative instructions as well, which are issued only when commit signals backwards that a nonspeculative instruction is at the head of the ROB. cpu/beta_cpu/inst_queue_impl.hh: Updated to allow for non-speculative instructions to be in the inst queue. Also added some debug functions. cpu/beta_cpu/regfile.hh: Added debugging statements, changed formatting. cpu/beta_cpu/rename.hh: Updated typedefs, added some functions to clean up code. cpu/beta_cpu/rename_impl.hh: Moved some code into functions to make it easier to read. cpu/beta_cpu/rename_map.cc: Changed int and float reg behavior to use a single flat namespace. In the future, the rename maps can be combined to a single rename map to save space. cpu/beta_cpu/rename_map.hh: Added destructor. cpu/beta_cpu/rob.hh: Updated it with change from DynInst to ref counted DynInst. cpu/beta_cpu/rob_impl.hh: Formatting, updated to use ref counted DynInst. cpu/static_inst.hh: Updated forward declaration for AlphaDynInst now that it is templated. --HG-- extra : convert_revision : 1045f240ee9b6a4bd368e1806aca029ebbdc6dd3
2004-09-23 20:06:03 +02:00
--insts_available;
continue;
}
Large update of several parts of my code. The most notable change is the inclusion of a full-fledged load/store queue. At the moment it still has some issues running, but most of the code is hopefully close to the final version. SConscript: arch/isa_parser.py: cpu/base_dyn_inst.cc: Remove OOO CPU stuff. arch/alpha/faults.hh: Add fake memory fault. This will be removed eventually. arch/alpha/isa_desc: Change EA comp and Mem accessor to be const StaticInstPtrs. cpu/base_dyn_inst.hh: Update read/write calls to use load queue and store queue indices. cpu/beta_cpu/alpha_dyn_inst.hh: Change to const StaticInst in the register accessors. cpu/beta_cpu/alpha_dyn_inst_impl.hh: Update syscall code with thread numbers. cpu/beta_cpu/alpha_full_cpu.hh: Alter some of the full system code so it will compile without errors. cpu/beta_cpu/alpha_full_cpu_builder.cc: Created a DerivAlphaFullCPU class so I can instantiate different CPUs that have different template parameters. cpu/beta_cpu/alpha_full_cpu_impl.hh: Update some of the full system code so it compiles. cpu/beta_cpu/alpha_params.hh: cpu/beta_cpu/fetch_impl.hh: Remove asid. cpu/beta_cpu/comm.hh: Remove global history field. cpu/beta_cpu/commit.hh: Comment out rename map. cpu/beta_cpu/commit_impl.hh: Update some of the full system code so it compiles. Also change it so that it handles memory instructions properly. cpu/beta_cpu/cpu_policy.hh: Removed IQ from the IEW template parameter to make it more uniform. cpu/beta_cpu/decode.hh: Add debug function. cpu/beta_cpu/decode_impl.hh: Slight updates for decode in the case where it causes a squash. cpu/beta_cpu/fetch.hh: cpu/beta_cpu/rob.hh: Comment out unneccessary code. cpu/beta_cpu/full_cpu.cc: Changed some of the full system code so it compiles. Updated exec contexts and so forth to hopefully make multithreading easier. cpu/beta_cpu/full_cpu.hh: Updated some of the full system code to make it compile. cpu/beta_cpu/iew.cc: Removed IQ from template parameter to IEW. cpu/beta_cpu/iew.hh: Removed IQ from template parameter to IEW. Updated IEW to recognize the Load/Store queue. cpu/beta_cpu/iew_impl.hh: New handling of memory instructions through the Load/Store queue. cpu/beta_cpu/inst_queue.hh: Updated comment. cpu/beta_cpu/inst_queue_impl.hh: Slightly different handling of memory instructions due to Load/Store queue. cpu/beta_cpu/regfile.hh: Updated full system code so it compiles. cpu/beta_cpu/rob_impl.hh: Moved some code around; no major functional changes. cpu/ooo_cpu/ooo_cpu.hh: Slight updates to OOO CPU; still does not work. cpu/static_inst.hh: Remove OOO CPU stuff. Change ea comp and mem acc to return const StaticInst. kern/kernel_stats.hh: Extra forward declares added due to compile error. --HG-- extra : convert_revision : 594a7cdbe57f6c2bda7d08856fcd864604a6238e
2005-05-03 16:56:47 +02:00
// Also check if instructions have no source registers. Mark
// them as ready to issue at any time. Not sure if this check
// should exist here or at a later stage; however it doesn't matter
// too much for function correctness.
if (inst->numSrcRegs() == 0) {
inst->setCanIssue();
}
// This current instruction is valid, so add it into the decode
// queue. The next instruction may not be valid, so check to
// see if branches were predicted correctly.
toRename->insts[toRenameIndex] = inst;
Update to make multiple instruction issue and different latencies work. Also change to ref counted DynInst. SConscript: Add branch predictor, BTB, load store queue, and storesets. arch/isa_parser.py: Specify the template parameter for AlphaDynInst base/traceflags.py: Add load store queue, store set, and mem dependence unit to the list of trace flags. cpu/base_dyn_inst.cc: Change formating, add in debug statement. cpu/base_dyn_inst.hh: Change DynInst to be RefCounted, add flag to clear whether or not this instruction can commit. This is likely to be removed in the future. cpu/beta_cpu/alpha_dyn_inst.cc: AlphaDynInst has been changed to be templated, so now this CC file is just used to force instantiations of AlphaDynInst. cpu/beta_cpu/alpha_dyn_inst.hh: Changed AlphaDynInst to be templated on Impl. Removed some unnecessary functions. cpu/beta_cpu/alpha_full_cpu.cc: AlphaFullCPU has been changed to be templated, so this CC file is now just used to force instantation of AlphaFullCPU. cpu/beta_cpu/alpha_full_cpu.hh: Change AlphaFullCPU to be templated on Impl. cpu/beta_cpu/alpha_impl.hh: Update it to reflect AlphaDynInst and AlphaFullCPU being templated on Impl. Also removed time buffers from here, as they are really a part of the CPU and are thus in the CPU policy now. cpu/beta_cpu/alpha_params.hh: Make AlphaSimpleParams inherit from the BaseFullCPU so that it doesn't need to specifically declare any parameters that are already in the BaseFullCPU. cpu/beta_cpu/comm.hh: Changed the structure of the time buffer communication structs. Now they include the size of the packet of instructions it is sending. Added some parameters to the backwards communication struct, mainly for squashing. cpu/beta_cpu/commit.hh: Update typenames to reflect change in location of time buffer structs. Update DynInst to DynInstPtr (it is refcounted now). cpu/beta_cpu/commit_impl.hh: Formatting changes mainly. Also sends back proper information on branch mispredicts so that the bpred unit can update itself. Updated behavior for non-speculative instructions (stores, any other non-spec instructions): once they reach the head of the ROB, the ROB signals back to the IQ that it can go ahead and issue the non-speculative instruction. The instruction itself is updated so that commit won't try to commit it again until it is done executing. cpu/beta_cpu/cpu_policy.hh: Added branch prediction unit, mem dependence prediction unit, load store queue. Moved time buffer structs from AlphaSimpleImpl to here. cpu/beta_cpu/decode.hh: Changed typedefs to reflect change in location of time buffer structs and also the change from DynInst to ref counted DynInstPtr. cpu/beta_cpu/decode_impl.hh: Continues to buffer instructions even while unblocking now. Changed how it loops through groups of instructions so it can properly block during the middle of a group of instructions. cpu/beta_cpu/fetch.hh: Changed typedefs to reflect change in location of time buffer structs and the change to ref counted DynInsts. Also added in branch brediction unit. cpu/beta_cpu/fetch_impl.hh: Add in branch prediction. Changed how fetch checks inputs and its current state to make for easier logic. cpu/beta_cpu/free_list.cc: Changed int regs and float regs to logically use one flat namespace. Future change will be moving them to a single scoreboard to conserve space. cpu/beta_cpu/free_list.hh: Mostly debugging statements. Might be removed for performance in future. cpu/beta_cpu/full_cpu.cc: Added in some debugging statements. Updated BaseFullCPU to take a params object. cpu/beta_cpu/full_cpu.hh: Added params class within BaseCPU that other param classes will be able to inherit from. Updated typedefs to reflect change in location of time buffer structs and ref counted DynInst. cpu/beta_cpu/iew.hh: Updated typedefs to reflect change in location of time buffer structs and use of ref counted DynInsts. cpu/beta_cpu/iew_impl.hh: Added in load store queue, updated iew to be able to execute non- speculative instructions, instead of having them execute in commit. cpu/beta_cpu/inst_queue.hh: Updated change to ref counted DynInsts. Changed inst queue to hold non-speculative instructions as well, which are issued only when commit signals backwards that a nonspeculative instruction is at the head of the ROB. cpu/beta_cpu/inst_queue_impl.hh: Updated to allow for non-speculative instructions to be in the inst queue. Also added some debug functions. cpu/beta_cpu/regfile.hh: Added debugging statements, changed formatting. cpu/beta_cpu/rename.hh: Updated typedefs, added some functions to clean up code. cpu/beta_cpu/rename_impl.hh: Moved some code into functions to make it easier to read. cpu/beta_cpu/rename_map.cc: Changed int and float reg behavior to use a single flat namespace. In the future, the rename maps can be combined to a single rename map to save space. cpu/beta_cpu/rename_map.hh: Added destructor. cpu/beta_cpu/rob.hh: Updated it with change from DynInst to ref counted DynInst. cpu/beta_cpu/rob_impl.hh: Formatting, updated to use ref counted DynInst. cpu/static_inst.hh: Updated forward declaration for AlphaDynInst now that it is templated. --HG-- extra : convert_revision : 1045f240ee9b6a4bd368e1806aca029ebbdc6dd3
2004-09-23 20:06:03 +02:00
++(toRename->size);
++toRenameIndex;
++decodeDecodedInsts;
--insts_available;
// Ensure that if it was predicted as a branch, it really is a
Update to make multiple instruction issue and different latencies work. Also change to ref counted DynInst. SConscript: Add branch predictor, BTB, load store queue, and storesets. arch/isa_parser.py: Specify the template parameter for AlphaDynInst base/traceflags.py: Add load store queue, store set, and mem dependence unit to the list of trace flags. cpu/base_dyn_inst.cc: Change formating, add in debug statement. cpu/base_dyn_inst.hh: Change DynInst to be RefCounted, add flag to clear whether or not this instruction can commit. This is likely to be removed in the future. cpu/beta_cpu/alpha_dyn_inst.cc: AlphaDynInst has been changed to be templated, so now this CC file is just used to force instantiations of AlphaDynInst. cpu/beta_cpu/alpha_dyn_inst.hh: Changed AlphaDynInst to be templated on Impl. Removed some unnecessary functions. cpu/beta_cpu/alpha_full_cpu.cc: AlphaFullCPU has been changed to be templated, so this CC file is now just used to force instantation of AlphaFullCPU. cpu/beta_cpu/alpha_full_cpu.hh: Change AlphaFullCPU to be templated on Impl. cpu/beta_cpu/alpha_impl.hh: Update it to reflect AlphaDynInst and AlphaFullCPU being templated on Impl. Also removed time buffers from here, as they are really a part of the CPU and are thus in the CPU policy now. cpu/beta_cpu/alpha_params.hh: Make AlphaSimpleParams inherit from the BaseFullCPU so that it doesn't need to specifically declare any parameters that are already in the BaseFullCPU. cpu/beta_cpu/comm.hh: Changed the structure of the time buffer communication structs. Now they include the size of the packet of instructions it is sending. Added some parameters to the backwards communication struct, mainly for squashing. cpu/beta_cpu/commit.hh: Update typenames to reflect change in location of time buffer structs. Update DynInst to DynInstPtr (it is refcounted now). cpu/beta_cpu/commit_impl.hh: Formatting changes mainly. Also sends back proper information on branch mispredicts so that the bpred unit can update itself. Updated behavior for non-speculative instructions (stores, any other non-spec instructions): once they reach the head of the ROB, the ROB signals back to the IQ that it can go ahead and issue the non-speculative instruction. The instruction itself is updated so that commit won't try to commit it again until it is done executing. cpu/beta_cpu/cpu_policy.hh: Added branch prediction unit, mem dependence prediction unit, load store queue. Moved time buffer structs from AlphaSimpleImpl to here. cpu/beta_cpu/decode.hh: Changed typedefs to reflect change in location of time buffer structs and also the change from DynInst to ref counted DynInstPtr. cpu/beta_cpu/decode_impl.hh: Continues to buffer instructions even while unblocking now. Changed how it loops through groups of instructions so it can properly block during the middle of a group of instructions. cpu/beta_cpu/fetch.hh: Changed typedefs to reflect change in location of time buffer structs and the change to ref counted DynInsts. Also added in branch brediction unit. cpu/beta_cpu/fetch_impl.hh: Add in branch prediction. Changed how fetch checks inputs and its current state to make for easier logic. cpu/beta_cpu/free_list.cc: Changed int regs and float regs to logically use one flat namespace. Future change will be moving them to a single scoreboard to conserve space. cpu/beta_cpu/free_list.hh: Mostly debugging statements. Might be removed for performance in future. cpu/beta_cpu/full_cpu.cc: Added in some debugging statements. Updated BaseFullCPU to take a params object. cpu/beta_cpu/full_cpu.hh: Added params class within BaseCPU that other param classes will be able to inherit from. Updated typedefs to reflect change in location of time buffer structs and ref counted DynInst. cpu/beta_cpu/iew.hh: Updated typedefs to reflect change in location of time buffer structs and use of ref counted DynInsts. cpu/beta_cpu/iew_impl.hh: Added in load store queue, updated iew to be able to execute non- speculative instructions, instead of having them execute in commit. cpu/beta_cpu/inst_queue.hh: Updated change to ref counted DynInsts. Changed inst queue to hold non-speculative instructions as well, which are issued only when commit signals backwards that a nonspeculative instruction is at the head of the ROB. cpu/beta_cpu/inst_queue_impl.hh: Updated to allow for non-speculative instructions to be in the inst queue. Also added some debug functions. cpu/beta_cpu/regfile.hh: Added debugging statements, changed formatting. cpu/beta_cpu/rename.hh: Updated typedefs, added some functions to clean up code. cpu/beta_cpu/rename_impl.hh: Moved some code into functions to make it easier to read. cpu/beta_cpu/rename_map.cc: Changed int and float reg behavior to use a single flat namespace. In the future, the rename maps can be combined to a single rename map to save space. cpu/beta_cpu/rename_map.hh: Added destructor. cpu/beta_cpu/rob.hh: Updated it with change from DynInst to ref counted DynInst. cpu/beta_cpu/rob_impl.hh: Formatting, updated to use ref counted DynInst. cpu/static_inst.hh: Updated forward declaration for AlphaDynInst now that it is templated. --HG-- extra : convert_revision : 1045f240ee9b6a4bd368e1806aca029ebbdc6dd3
2004-09-23 20:06:03 +02:00
// branch.
if (inst->readPredTaken() && !inst->isControl()) {
panic("Instruction predicted as a branch!");
Check in of various updates to the CPU. Mainly adds in stats, improves branch prediction, and makes memory dependence work properly. SConscript: Added return address stack, tournament predictor. cpu/base_cpu.cc: Added debug break and print statements. cpu/base_dyn_inst.cc: cpu/base_dyn_inst.hh: Comment out possibly unneeded variables. cpu/beta_cpu/2bit_local_pred.cc: 2bit predictor no longer speculatively updates itself. cpu/beta_cpu/alpha_dyn_inst.hh: Comment formatting. cpu/beta_cpu/alpha_full_cpu.hh: Formatting cpu/beta_cpu/alpha_full_cpu_builder.cc: Added new parameters for branch predictors, and IQ parameters. cpu/beta_cpu/alpha_full_cpu_impl.hh: Register stats. cpu/beta_cpu/alpha_params.hh: Added parameters for IQ, branch predictors, and store sets. cpu/beta_cpu/bpred_unit.cc: Removed one class. cpu/beta_cpu/bpred_unit.hh: Add in RAS, stats. Changed branch predictor unit functionality so that it holds a history of past branches so it can update, and also hold a proper history of the RAS so it can be restored on branch mispredicts. cpu/beta_cpu/bpred_unit_impl.hh: Added in stats, history of branches, RAS. Now bpred unit actually modifies the instruction's predicted next PC. cpu/beta_cpu/btb.cc: Add in sanity checks. cpu/beta_cpu/comm.hh: Add in communication where needed, remove it where it's not. cpu/beta_cpu/commit.hh: cpu/beta_cpu/rename.hh: cpu/beta_cpu/rename_impl.hh: Add in stats. cpu/beta_cpu/commit_impl.hh: Stats, update what is sent back on branch mispredict. cpu/beta_cpu/cpu_policy.hh: Change the bpred unit being used. cpu/beta_cpu/decode.hh: cpu/beta_cpu/decode_impl.hh: Stats. cpu/beta_cpu/fetch.hh: Stats, change squash so it can handle squashes from decode differently than squashes from commit. cpu/beta_cpu/fetch_impl.hh: Add in stats. Change how a cache line is fetched. Update to work with caches. Also have separate functions for different behavior if squash is coming from decode vs commit. cpu/beta_cpu/free_list.hh: Remove some old comments. cpu/beta_cpu/full_cpu.cc: cpu/beta_cpu/full_cpu.hh: Added function to remove instructions from back of instruction list until a certain sequence number. cpu/beta_cpu/iew.hh: Stats, separate squashing behavior due to branches vs memory. cpu/beta_cpu/iew_impl.hh: Stats, separate squashing behavior for branches vs memory. cpu/beta_cpu/inst_queue.cc: Debug stuff cpu/beta_cpu/inst_queue.hh: Stats, change how mem dep unit works, debug stuff cpu/beta_cpu/inst_queue_impl.hh: Stats, change how mem dep unit works, debug stuff. Also add in parameters that used to be hardcoded. cpu/beta_cpu/mem_dep_unit.hh: cpu/beta_cpu/mem_dep_unit_impl.hh: Add in stats, change how memory dependence unit works. It now holds the memory instructions that are waiting for their memory dependences to resolve. It provides which instructions are ready directly to the IQ. cpu/beta_cpu/regfile.hh: Fix up sanity checks. cpu/beta_cpu/rename_map.cc: Fix loop variable type. cpu/beta_cpu/rob_impl.hh: Remove intermediate DynInstPtr cpu/beta_cpu/store_set.cc: Add in debugging statements. cpu/beta_cpu/store_set.hh: Reorder function arguments to match the rest of the calls. --HG-- extra : convert_revision : aabf9b1fecd1d743265dfc3b174d6159937c6f44
2004-10-22 00:02:36 +02:00
++decodeControlMispred;
// Might want to set some sort of boolean and just do
// a check at the end
squash(inst, inst->threadNumber);
break;
}
Check in of various updates to the CPU. Mainly adds in stats, improves branch prediction, and makes memory dependence work properly. SConscript: Added return address stack, tournament predictor. cpu/base_cpu.cc: Added debug break and print statements. cpu/base_dyn_inst.cc: cpu/base_dyn_inst.hh: Comment out possibly unneeded variables. cpu/beta_cpu/2bit_local_pred.cc: 2bit predictor no longer speculatively updates itself. cpu/beta_cpu/alpha_dyn_inst.hh: Comment formatting. cpu/beta_cpu/alpha_full_cpu.hh: Formatting cpu/beta_cpu/alpha_full_cpu_builder.cc: Added new parameters for branch predictors, and IQ parameters. cpu/beta_cpu/alpha_full_cpu_impl.hh: Register stats. cpu/beta_cpu/alpha_params.hh: Added parameters for IQ, branch predictors, and store sets. cpu/beta_cpu/bpred_unit.cc: Removed one class. cpu/beta_cpu/bpred_unit.hh: Add in RAS, stats. Changed branch predictor unit functionality so that it holds a history of past branches so it can update, and also hold a proper history of the RAS so it can be restored on branch mispredicts. cpu/beta_cpu/bpred_unit_impl.hh: Added in stats, history of branches, RAS. Now bpred unit actually modifies the instruction's predicted next PC. cpu/beta_cpu/btb.cc: Add in sanity checks. cpu/beta_cpu/comm.hh: Add in communication where needed, remove it where it's not. cpu/beta_cpu/commit.hh: cpu/beta_cpu/rename.hh: cpu/beta_cpu/rename_impl.hh: Add in stats. cpu/beta_cpu/commit_impl.hh: Stats, update what is sent back on branch mispredict. cpu/beta_cpu/cpu_policy.hh: Change the bpred unit being used. cpu/beta_cpu/decode.hh: cpu/beta_cpu/decode_impl.hh: Stats. cpu/beta_cpu/fetch.hh: Stats, change squash so it can handle squashes from decode differently than squashes from commit. cpu/beta_cpu/fetch_impl.hh: Add in stats. Change how a cache line is fetched. Update to work with caches. Also have separate functions for different behavior if squash is coming from decode vs commit. cpu/beta_cpu/free_list.hh: Remove some old comments. cpu/beta_cpu/full_cpu.cc: cpu/beta_cpu/full_cpu.hh: Added function to remove instructions from back of instruction list until a certain sequence number. cpu/beta_cpu/iew.hh: Stats, separate squashing behavior due to branches vs memory. cpu/beta_cpu/iew_impl.hh: Stats, separate squashing behavior for branches vs memory. cpu/beta_cpu/inst_queue.cc: Debug stuff cpu/beta_cpu/inst_queue.hh: Stats, change how mem dep unit works, debug stuff cpu/beta_cpu/inst_queue_impl.hh: Stats, change how mem dep unit works, debug stuff. Also add in parameters that used to be hardcoded. cpu/beta_cpu/mem_dep_unit.hh: cpu/beta_cpu/mem_dep_unit_impl.hh: Add in stats, change how memory dependence unit works. It now holds the memory instructions that are waiting for their memory dependences to resolve. It provides which instructions are ready directly to the IQ. cpu/beta_cpu/regfile.hh: Fix up sanity checks. cpu/beta_cpu/rename_map.cc: Fix loop variable type. cpu/beta_cpu/rob_impl.hh: Remove intermediate DynInstPtr cpu/beta_cpu/store_set.cc: Add in debugging statements. cpu/beta_cpu/store_set.hh: Reorder function arguments to match the rest of the calls. --HG-- extra : convert_revision : aabf9b1fecd1d743265dfc3b174d6159937c6f44
2004-10-22 00:02:36 +02:00
// Go ahead and compute any PC-relative branches.
if (inst->isDirectCtrl() && inst->isUncondCtrl()) {
++decodeBranchResolved;
Check in of various updates to the CPU. Mainly adds in stats, improves branch prediction, and makes memory dependence work properly. SConscript: Added return address stack, tournament predictor. cpu/base_cpu.cc: Added debug break and print statements. cpu/base_dyn_inst.cc: cpu/base_dyn_inst.hh: Comment out possibly unneeded variables. cpu/beta_cpu/2bit_local_pred.cc: 2bit predictor no longer speculatively updates itself. cpu/beta_cpu/alpha_dyn_inst.hh: Comment formatting. cpu/beta_cpu/alpha_full_cpu.hh: Formatting cpu/beta_cpu/alpha_full_cpu_builder.cc: Added new parameters for branch predictors, and IQ parameters. cpu/beta_cpu/alpha_full_cpu_impl.hh: Register stats. cpu/beta_cpu/alpha_params.hh: Added parameters for IQ, branch predictors, and store sets. cpu/beta_cpu/bpred_unit.cc: Removed one class. cpu/beta_cpu/bpred_unit.hh: Add in RAS, stats. Changed branch predictor unit functionality so that it holds a history of past branches so it can update, and also hold a proper history of the RAS so it can be restored on branch mispredicts. cpu/beta_cpu/bpred_unit_impl.hh: Added in stats, history of branches, RAS. Now bpred unit actually modifies the instruction's predicted next PC. cpu/beta_cpu/btb.cc: Add in sanity checks. cpu/beta_cpu/comm.hh: Add in communication where needed, remove it where it's not. cpu/beta_cpu/commit.hh: cpu/beta_cpu/rename.hh: cpu/beta_cpu/rename_impl.hh: Add in stats. cpu/beta_cpu/commit_impl.hh: Stats, update what is sent back on branch mispredict. cpu/beta_cpu/cpu_policy.hh: Change the bpred unit being used. cpu/beta_cpu/decode.hh: cpu/beta_cpu/decode_impl.hh: Stats. cpu/beta_cpu/fetch.hh: Stats, change squash so it can handle squashes from decode differently than squashes from commit. cpu/beta_cpu/fetch_impl.hh: Add in stats. Change how a cache line is fetched. Update to work with caches. Also have separate functions for different behavior if squash is coming from decode vs commit. cpu/beta_cpu/free_list.hh: Remove some old comments. cpu/beta_cpu/full_cpu.cc: cpu/beta_cpu/full_cpu.hh: Added function to remove instructions from back of instruction list until a certain sequence number. cpu/beta_cpu/iew.hh: Stats, separate squashing behavior due to branches vs memory. cpu/beta_cpu/iew_impl.hh: Stats, separate squashing behavior for branches vs memory. cpu/beta_cpu/inst_queue.cc: Debug stuff cpu/beta_cpu/inst_queue.hh: Stats, change how mem dep unit works, debug stuff cpu/beta_cpu/inst_queue_impl.hh: Stats, change how mem dep unit works, debug stuff. Also add in parameters that used to be hardcoded. cpu/beta_cpu/mem_dep_unit.hh: cpu/beta_cpu/mem_dep_unit_impl.hh: Add in stats, change how memory dependence unit works. It now holds the memory instructions that are waiting for their memory dependences to resolve. It provides which instructions are ready directly to the IQ. cpu/beta_cpu/regfile.hh: Fix up sanity checks. cpu/beta_cpu/rename_map.cc: Fix loop variable type. cpu/beta_cpu/rob_impl.hh: Remove intermediate DynInstPtr cpu/beta_cpu/store_set.cc: Add in debugging statements. cpu/beta_cpu/store_set.hh: Reorder function arguments to match the rest of the calls. --HG-- extra : convert_revision : aabf9b1fecd1d743265dfc3b174d6159937c6f44
2004-10-22 00:02:36 +02:00
ISA,CPU,etc: Create an ISA defined PC type that abstracts out ISA behaviors. This change is a low level and pervasive reorganization of how PCs are managed in M5. Back when Alpha was the only ISA, there were only 2 PCs to worry about, the PC and the NPC, and the lsb of the PC signaled whether or not you were in PAL mode. As other ISAs were added, we had to add an NNPC, micro PC and next micropc, x86 and ARM introduced variable length instruction sets, and ARM started to keep track of mode bits in the PC. Each CPU model handled PCs in its own custom way that needed to be updated individually to handle the new dimensions of variability, or, in the case of ARMs mode-bit-in-the-pc hack, the complexity could be hidden in the ISA at the ISA implementation's expense. Areas like the branch predictor hadn't been updated to handle branch delay slots or micropcs, and it turns out that had introduced a significant (10s of percent) performance bug in SPARC and to a lesser extend MIPS. Rather than perpetuate the problem by reworking O3 again to handle the PC features needed by x86, this change was introduced to rework PC handling in a more modular, transparent, and hopefully efficient way. PC type: Rather than having the superset of all possible elements of PC state declared in each of the CPU models, each ISA defines its own PCState type which has exactly the elements it needs. A cross product of canned PCState classes are defined in the new "generic" ISA directory for ISAs with/without delay slots and microcode. These are either typedef-ed or subclassed by each ISA. To read or write this structure through a *Context, you use the new pcState() accessor which reads or writes depending on whether it has an argument. If you just want the address of the current or next instruction or the current micro PC, you can get those through read-only accessors on either the PCState type or the *Contexts. These are instAddr(), nextInstAddr(), and microPC(). Note the move away from readPC. That name is ambiguous since it's not clear whether or not it should be the actual address to fetch from, or if it should have extra bits in it like the PAL mode bit. Each class is free to define its own functions to get at whatever values it needs however it needs to to be used in ISA specific code. Eventually Alpha's PAL mode bit could be moved out of the PC and into a separate field like ARM. These types can be reset to a particular pc (where npc = pc + sizeof(MachInst), nnpc = npc + sizeof(MachInst), upc = 0, nupc = 1 as appropriate), printed, serialized, and compared. There is a branching() function which encapsulates code in the CPU models that checked if an instruction branched or not. Exactly what that means in the context of branch delay slots which can skip an instruction when not taken is ambiguous, and ideally this function and its uses can be eliminated. PCStates also generally know how to advance themselves in various ways depending on if they point at an instruction, a microop, or the last microop of a macroop. More on that later. Ideally, accessing all the PCs at once when setting them will improve performance of M5 even though more data needs to be moved around. This is because often all the PCs need to be manipulated together, and by getting them all at once you avoid multiple function calls. Also, the PCs of a particular thread will have spatial locality in the cache. Previously they were grouped by element in arrays which spread out accesses. Advancing the PC: The PCs were previously managed entirely by the CPU which had to know about PC semantics, try to figure out which dimension to increment the PC in, what to set NPC/NNPC, etc. These decisions are best left to the ISA in conjunction with the PC type itself. Because most of the information about how to increment the PC (mainly what type of instruction it refers to) is contained in the instruction object, a new advancePC virtual function was added to the StaticInst class. Subclasses provide an implementation that moves around the right element of the PC with a minimal amount of decision making. In ISAs like Alpha, the instructions always simply assign NPC to PC without having to worry about micropcs, nnpcs, etc. The added cost of a virtual function call should be outweighed by not having to figure out as much about what to do with the PCs and mucking around with the extra elements. One drawback of making the StaticInsts advance the PC is that you have to actually have one to advance the PC. This would, superficially, seem to require decoding an instruction before fetch could advance. This is, as far as I can tell, realistic. fetch would advance through memory addresses, not PCs, perhaps predicting new memory addresses using existing ones. More sophisticated decisions about control flow would be made later on, after the instruction was decoded, and handed back to fetch. If branching needs to happen, some amount of decoding needs to happen to see that it's a branch, what the target is, etc. This could get a little more complicated if that gets done by the predecoder, but I'm choosing to ignore that for now. Variable length instructions: To handle variable length instructions in x86 and ARM, the predecoder now takes in the current PC by reference to the getExtMachInst function. It can modify the PC however it needs to (by setting NPC to be the PC + instruction length, for instance). This could be improved since the CPU doesn't know if the PC was modified and always has to write it back. ISA parser: To support the new API, all PC related operand types were removed from the parser and replaced with a PCState type. There are two warts on this implementation. First, as with all the other operand types, the PCState still has to have a valid operand type even though it doesn't use it. Second, using syntax like PCS.npc(target) doesn't work for two reasons, this looks like the syntax for operand type overriding, and the parser can't figure out if you're reading or writing. Instructions that use the PCS operand (which I've consistently called it) need to first read it into a local variable, manipulate it, and then write it back out. Return address stack: The return address stack needed a little extra help because, in the presence of branch delay slots, it has to merge together elements of the return PC and the call PC. To handle that, a buildRetPC utility function was added. There are basically only two versions in all the ISAs, but it didn't seem short enough to put into the generic ISA directory. Also, the branch predictor code in O3 and InOrder were adjusted so that they always store the PC of the actual call instruction in the RAS, not the next PC. If the call instruction is a microop, the next PC refers to the next microop in the same macroop which is probably not desirable. The buildRetPC function advances the PC intelligently to the next macroop (in an ISA specific way) so that that case works. Change in stats: There were no change in stats except in MIPS and SPARC in the O3 model. MIPS runs in about 9% fewer ticks. SPARC runs with 30%-50% fewer ticks, which could likely be improved further by setting call/return instruction flags and taking advantage of the RAS. TODO: Add != operators to the PCState classes, defined trivially to be !(a==b). Smooth out places where PCs are split apart, passed around, and put back together later. I think this might happen in SPARC's fault code. Add ISA specific constructors that allow setting PC elements without calling a bunch of accessors. Try to eliminate the need for the branching() function. Factor out Alpha's PAL mode pc bit into a separate flag field, and eliminate places where it's blindly masked out or tested in the PC.
2010-10-31 08:07:20 +01:00
if (!(inst->branchTarget() == inst->readPredTarg())) {
Check in of various updates to the CPU. Mainly adds in stats, improves branch prediction, and makes memory dependence work properly. SConscript: Added return address stack, tournament predictor. cpu/base_cpu.cc: Added debug break and print statements. cpu/base_dyn_inst.cc: cpu/base_dyn_inst.hh: Comment out possibly unneeded variables. cpu/beta_cpu/2bit_local_pred.cc: 2bit predictor no longer speculatively updates itself. cpu/beta_cpu/alpha_dyn_inst.hh: Comment formatting. cpu/beta_cpu/alpha_full_cpu.hh: Formatting cpu/beta_cpu/alpha_full_cpu_builder.cc: Added new parameters for branch predictors, and IQ parameters. cpu/beta_cpu/alpha_full_cpu_impl.hh: Register stats. cpu/beta_cpu/alpha_params.hh: Added parameters for IQ, branch predictors, and store sets. cpu/beta_cpu/bpred_unit.cc: Removed one class. cpu/beta_cpu/bpred_unit.hh: Add in RAS, stats. Changed branch predictor unit functionality so that it holds a history of past branches so it can update, and also hold a proper history of the RAS so it can be restored on branch mispredicts. cpu/beta_cpu/bpred_unit_impl.hh: Added in stats, history of branches, RAS. Now bpred unit actually modifies the instruction's predicted next PC. cpu/beta_cpu/btb.cc: Add in sanity checks. cpu/beta_cpu/comm.hh: Add in communication where needed, remove it where it's not. cpu/beta_cpu/commit.hh: cpu/beta_cpu/rename.hh: cpu/beta_cpu/rename_impl.hh: Add in stats. cpu/beta_cpu/commit_impl.hh: Stats, update what is sent back on branch mispredict. cpu/beta_cpu/cpu_policy.hh: Change the bpred unit being used. cpu/beta_cpu/decode.hh: cpu/beta_cpu/decode_impl.hh: Stats. cpu/beta_cpu/fetch.hh: Stats, change squash so it can handle squashes from decode differently than squashes from commit. cpu/beta_cpu/fetch_impl.hh: Add in stats. Change how a cache line is fetched. Update to work with caches. Also have separate functions for different behavior if squash is coming from decode vs commit. cpu/beta_cpu/free_list.hh: Remove some old comments. cpu/beta_cpu/full_cpu.cc: cpu/beta_cpu/full_cpu.hh: Added function to remove instructions from back of instruction list until a certain sequence number. cpu/beta_cpu/iew.hh: Stats, separate squashing behavior due to branches vs memory. cpu/beta_cpu/iew_impl.hh: Stats, separate squashing behavior for branches vs memory. cpu/beta_cpu/inst_queue.cc: Debug stuff cpu/beta_cpu/inst_queue.hh: Stats, change how mem dep unit works, debug stuff cpu/beta_cpu/inst_queue_impl.hh: Stats, change how mem dep unit works, debug stuff. Also add in parameters that used to be hardcoded. cpu/beta_cpu/mem_dep_unit.hh: cpu/beta_cpu/mem_dep_unit_impl.hh: Add in stats, change how memory dependence unit works. It now holds the memory instructions that are waiting for their memory dependences to resolve. It provides which instructions are ready directly to the IQ. cpu/beta_cpu/regfile.hh: Fix up sanity checks. cpu/beta_cpu/rename_map.cc: Fix loop variable type. cpu/beta_cpu/rob_impl.hh: Remove intermediate DynInstPtr cpu/beta_cpu/store_set.cc: Add in debugging statements. cpu/beta_cpu/store_set.hh: Reorder function arguments to match the rest of the calls. --HG-- extra : convert_revision : aabf9b1fecd1d743265dfc3b174d6159937c6f44
2004-10-22 00:02:36 +02:00
++decodeBranchMispred;
// Might want to set some sort of boolean and just do
// a check at the end
squash(inst, inst->threadNumber);
ISA,CPU,etc: Create an ISA defined PC type that abstracts out ISA behaviors. This change is a low level and pervasive reorganization of how PCs are managed in M5. Back when Alpha was the only ISA, there were only 2 PCs to worry about, the PC and the NPC, and the lsb of the PC signaled whether or not you were in PAL mode. As other ISAs were added, we had to add an NNPC, micro PC and next micropc, x86 and ARM introduced variable length instruction sets, and ARM started to keep track of mode bits in the PC. Each CPU model handled PCs in its own custom way that needed to be updated individually to handle the new dimensions of variability, or, in the case of ARMs mode-bit-in-the-pc hack, the complexity could be hidden in the ISA at the ISA implementation's expense. Areas like the branch predictor hadn't been updated to handle branch delay slots or micropcs, and it turns out that had introduced a significant (10s of percent) performance bug in SPARC and to a lesser extend MIPS. Rather than perpetuate the problem by reworking O3 again to handle the PC features needed by x86, this change was introduced to rework PC handling in a more modular, transparent, and hopefully efficient way. PC type: Rather than having the superset of all possible elements of PC state declared in each of the CPU models, each ISA defines its own PCState type which has exactly the elements it needs. A cross product of canned PCState classes are defined in the new "generic" ISA directory for ISAs with/without delay slots and microcode. These are either typedef-ed or subclassed by each ISA. To read or write this structure through a *Context, you use the new pcState() accessor which reads or writes depending on whether it has an argument. If you just want the address of the current or next instruction or the current micro PC, you can get those through read-only accessors on either the PCState type or the *Contexts. These are instAddr(), nextInstAddr(), and microPC(). Note the move away from readPC. That name is ambiguous since it's not clear whether or not it should be the actual address to fetch from, or if it should have extra bits in it like the PAL mode bit. Each class is free to define its own functions to get at whatever values it needs however it needs to to be used in ISA specific code. Eventually Alpha's PAL mode bit could be moved out of the PC and into a separate field like ARM. These types can be reset to a particular pc (where npc = pc + sizeof(MachInst), nnpc = npc + sizeof(MachInst), upc = 0, nupc = 1 as appropriate), printed, serialized, and compared. There is a branching() function which encapsulates code in the CPU models that checked if an instruction branched or not. Exactly what that means in the context of branch delay slots which can skip an instruction when not taken is ambiguous, and ideally this function and its uses can be eliminated. PCStates also generally know how to advance themselves in various ways depending on if they point at an instruction, a microop, or the last microop of a macroop. More on that later. Ideally, accessing all the PCs at once when setting them will improve performance of M5 even though more data needs to be moved around. This is because often all the PCs need to be manipulated together, and by getting them all at once you avoid multiple function calls. Also, the PCs of a particular thread will have spatial locality in the cache. Previously they were grouped by element in arrays which spread out accesses. Advancing the PC: The PCs were previously managed entirely by the CPU which had to know about PC semantics, try to figure out which dimension to increment the PC in, what to set NPC/NNPC, etc. These decisions are best left to the ISA in conjunction with the PC type itself. Because most of the information about how to increment the PC (mainly what type of instruction it refers to) is contained in the instruction object, a new advancePC virtual function was added to the StaticInst class. Subclasses provide an implementation that moves around the right element of the PC with a minimal amount of decision making. In ISAs like Alpha, the instructions always simply assign NPC to PC without having to worry about micropcs, nnpcs, etc. The added cost of a virtual function call should be outweighed by not having to figure out as much about what to do with the PCs and mucking around with the extra elements. One drawback of making the StaticInsts advance the PC is that you have to actually have one to advance the PC. This would, superficially, seem to require decoding an instruction before fetch could advance. This is, as far as I can tell, realistic. fetch would advance through memory addresses, not PCs, perhaps predicting new memory addresses using existing ones. More sophisticated decisions about control flow would be made later on, after the instruction was decoded, and handed back to fetch. If branching needs to happen, some amount of decoding needs to happen to see that it's a branch, what the target is, etc. This could get a little more complicated if that gets done by the predecoder, but I'm choosing to ignore that for now. Variable length instructions: To handle variable length instructions in x86 and ARM, the predecoder now takes in the current PC by reference to the getExtMachInst function. It can modify the PC however it needs to (by setting NPC to be the PC + instruction length, for instance). This could be improved since the CPU doesn't know if the PC was modified and always has to write it back. ISA parser: To support the new API, all PC related operand types were removed from the parser and replaced with a PCState type. There are two warts on this implementation. First, as with all the other operand types, the PCState still has to have a valid operand type even though it doesn't use it. Second, using syntax like PCS.npc(target) doesn't work for two reasons, this looks like the syntax for operand type overriding, and the parser can't figure out if you're reading or writing. Instructions that use the PCS operand (which I've consistently called it) need to first read it into a local variable, manipulate it, and then write it back out. Return address stack: The return address stack needed a little extra help because, in the presence of branch delay slots, it has to merge together elements of the return PC and the call PC. To handle that, a buildRetPC utility function was added. There are basically only two versions in all the ISAs, but it didn't seem short enough to put into the generic ISA directory. Also, the branch predictor code in O3 and InOrder were adjusted so that they always store the PC of the actual call instruction in the RAS, not the next PC. If the call instruction is a microop, the next PC refers to the next microop in the same macroop which is probably not desirable. The buildRetPC function advances the PC intelligently to the next macroop (in an ISA specific way) so that that case works. Change in stats: There were no change in stats except in MIPS and SPARC in the O3 model. MIPS runs in about 9% fewer ticks. SPARC runs with 30%-50% fewer ticks, which could likely be improved further by setting call/return instruction flags and taking advantage of the RAS. TODO: Add != operators to the PCState classes, defined trivially to be !(a==b). Smooth out places where PCs are split apart, passed around, and put back together later. I think this might happen in SPARC's fault code. Add ISA specific constructors that allow setting PC elements without calling a bunch of accessors. Try to eliminate the need for the branching() function. Factor out Alpha's PAL mode pc bit into a separate flag field, and eliminate places where it's blindly masked out or tested in the PC.
2010-10-31 08:07:20 +01:00
TheISA::PCState target = inst->branchTarget();
ISA,CPU,etc: Create an ISA defined PC type that abstracts out ISA behaviors. This change is a low level and pervasive reorganization of how PCs are managed in M5. Back when Alpha was the only ISA, there were only 2 PCs to worry about, the PC and the NPC, and the lsb of the PC signaled whether or not you were in PAL mode. As other ISAs were added, we had to add an NNPC, micro PC and next micropc, x86 and ARM introduced variable length instruction sets, and ARM started to keep track of mode bits in the PC. Each CPU model handled PCs in its own custom way that needed to be updated individually to handle the new dimensions of variability, or, in the case of ARMs mode-bit-in-the-pc hack, the complexity could be hidden in the ISA at the ISA implementation's expense. Areas like the branch predictor hadn't been updated to handle branch delay slots or micropcs, and it turns out that had introduced a significant (10s of percent) performance bug in SPARC and to a lesser extend MIPS. Rather than perpetuate the problem by reworking O3 again to handle the PC features needed by x86, this change was introduced to rework PC handling in a more modular, transparent, and hopefully efficient way. PC type: Rather than having the superset of all possible elements of PC state declared in each of the CPU models, each ISA defines its own PCState type which has exactly the elements it needs. A cross product of canned PCState classes are defined in the new "generic" ISA directory for ISAs with/without delay slots and microcode. These are either typedef-ed or subclassed by each ISA. To read or write this structure through a *Context, you use the new pcState() accessor which reads or writes depending on whether it has an argument. If you just want the address of the current or next instruction or the current micro PC, you can get those through read-only accessors on either the PCState type or the *Contexts. These are instAddr(), nextInstAddr(), and microPC(). Note the move away from readPC. That name is ambiguous since it's not clear whether or not it should be the actual address to fetch from, or if it should have extra bits in it like the PAL mode bit. Each class is free to define its own functions to get at whatever values it needs however it needs to to be used in ISA specific code. Eventually Alpha's PAL mode bit could be moved out of the PC and into a separate field like ARM. These types can be reset to a particular pc (where npc = pc + sizeof(MachInst), nnpc = npc + sizeof(MachInst), upc = 0, nupc = 1 as appropriate), printed, serialized, and compared. There is a branching() function which encapsulates code in the CPU models that checked if an instruction branched or not. Exactly what that means in the context of branch delay slots which can skip an instruction when not taken is ambiguous, and ideally this function and its uses can be eliminated. PCStates also generally know how to advance themselves in various ways depending on if they point at an instruction, a microop, or the last microop of a macroop. More on that later. Ideally, accessing all the PCs at once when setting them will improve performance of M5 even though more data needs to be moved around. This is because often all the PCs need to be manipulated together, and by getting them all at once you avoid multiple function calls. Also, the PCs of a particular thread will have spatial locality in the cache. Previously they were grouped by element in arrays which spread out accesses. Advancing the PC: The PCs were previously managed entirely by the CPU which had to know about PC semantics, try to figure out which dimension to increment the PC in, what to set NPC/NNPC, etc. These decisions are best left to the ISA in conjunction with the PC type itself. Because most of the information about how to increment the PC (mainly what type of instruction it refers to) is contained in the instruction object, a new advancePC virtual function was added to the StaticInst class. Subclasses provide an implementation that moves around the right element of the PC with a minimal amount of decision making. In ISAs like Alpha, the instructions always simply assign NPC to PC without having to worry about micropcs, nnpcs, etc. The added cost of a virtual function call should be outweighed by not having to figure out as much about what to do with the PCs and mucking around with the extra elements. One drawback of making the StaticInsts advance the PC is that you have to actually have one to advance the PC. This would, superficially, seem to require decoding an instruction before fetch could advance. This is, as far as I can tell, realistic. fetch would advance through memory addresses, not PCs, perhaps predicting new memory addresses using existing ones. More sophisticated decisions about control flow would be made later on, after the instruction was decoded, and handed back to fetch. If branching needs to happen, some amount of decoding needs to happen to see that it's a branch, what the target is, etc. This could get a little more complicated if that gets done by the predecoder, but I'm choosing to ignore that for now. Variable length instructions: To handle variable length instructions in x86 and ARM, the predecoder now takes in the current PC by reference to the getExtMachInst function. It can modify the PC however it needs to (by setting NPC to be the PC + instruction length, for instance). This could be improved since the CPU doesn't know if the PC was modified and always has to write it back. ISA parser: To support the new API, all PC related operand types were removed from the parser and replaced with a PCState type. There are two warts on this implementation. First, as with all the other operand types, the PCState still has to have a valid operand type even though it doesn't use it. Second, using syntax like PCS.npc(target) doesn't work for two reasons, this looks like the syntax for operand type overriding, and the parser can't figure out if you're reading or writing. Instructions that use the PCS operand (which I've consistently called it) need to first read it into a local variable, manipulate it, and then write it back out. Return address stack: The return address stack needed a little extra help because, in the presence of branch delay slots, it has to merge together elements of the return PC and the call PC. To handle that, a buildRetPC utility function was added. There are basically only two versions in all the ISAs, but it didn't seem short enough to put into the generic ISA directory. Also, the branch predictor code in O3 and InOrder were adjusted so that they always store the PC of the actual call instruction in the RAS, not the next PC. If the call instruction is a microop, the next PC refers to the next microop in the same macroop which is probably not desirable. The buildRetPC function advances the PC intelligently to the next macroop (in an ISA specific way) so that that case works. Change in stats: There were no change in stats except in MIPS and SPARC in the O3 model. MIPS runs in about 9% fewer ticks. SPARC runs with 30%-50% fewer ticks, which could likely be improved further by setting call/return instruction flags and taking advantage of the RAS. TODO: Add != operators to the PCState classes, defined trivially to be !(a==b). Smooth out places where PCs are split apart, passed around, and put back together later. I think this might happen in SPARC's fault code. Add ISA specific constructors that allow setting PC elements without calling a bunch of accessors. Try to eliminate the need for the branching() function. Factor out Alpha's PAL mode pc bit into a separate flag field, and eliminate places where it's blindly masked out or tested in the PC.
2010-10-31 08:07:20 +01:00
DPRINTF(Decode, "[sn:%i]: Updating predictions: PredPC: %s\n",
inst->seqNum, target);
//The micro pc after an instruction level branch should be 0
ISA,CPU,etc: Create an ISA defined PC type that abstracts out ISA behaviors. This change is a low level and pervasive reorganization of how PCs are managed in M5. Back when Alpha was the only ISA, there were only 2 PCs to worry about, the PC and the NPC, and the lsb of the PC signaled whether or not you were in PAL mode. As other ISAs were added, we had to add an NNPC, micro PC and next micropc, x86 and ARM introduced variable length instruction sets, and ARM started to keep track of mode bits in the PC. Each CPU model handled PCs in its own custom way that needed to be updated individually to handle the new dimensions of variability, or, in the case of ARMs mode-bit-in-the-pc hack, the complexity could be hidden in the ISA at the ISA implementation's expense. Areas like the branch predictor hadn't been updated to handle branch delay slots or micropcs, and it turns out that had introduced a significant (10s of percent) performance bug in SPARC and to a lesser extend MIPS. Rather than perpetuate the problem by reworking O3 again to handle the PC features needed by x86, this change was introduced to rework PC handling in a more modular, transparent, and hopefully efficient way. PC type: Rather than having the superset of all possible elements of PC state declared in each of the CPU models, each ISA defines its own PCState type which has exactly the elements it needs. A cross product of canned PCState classes are defined in the new "generic" ISA directory for ISAs with/without delay slots and microcode. These are either typedef-ed or subclassed by each ISA. To read or write this structure through a *Context, you use the new pcState() accessor which reads or writes depending on whether it has an argument. If you just want the address of the current or next instruction or the current micro PC, you can get those through read-only accessors on either the PCState type or the *Contexts. These are instAddr(), nextInstAddr(), and microPC(). Note the move away from readPC. That name is ambiguous since it's not clear whether or not it should be the actual address to fetch from, or if it should have extra bits in it like the PAL mode bit. Each class is free to define its own functions to get at whatever values it needs however it needs to to be used in ISA specific code. Eventually Alpha's PAL mode bit could be moved out of the PC and into a separate field like ARM. These types can be reset to a particular pc (where npc = pc + sizeof(MachInst), nnpc = npc + sizeof(MachInst), upc = 0, nupc = 1 as appropriate), printed, serialized, and compared. There is a branching() function which encapsulates code in the CPU models that checked if an instruction branched or not. Exactly what that means in the context of branch delay slots which can skip an instruction when not taken is ambiguous, and ideally this function and its uses can be eliminated. PCStates also generally know how to advance themselves in various ways depending on if they point at an instruction, a microop, or the last microop of a macroop. More on that later. Ideally, accessing all the PCs at once when setting them will improve performance of M5 even though more data needs to be moved around. This is because often all the PCs need to be manipulated together, and by getting them all at once you avoid multiple function calls. Also, the PCs of a particular thread will have spatial locality in the cache. Previously they were grouped by element in arrays which spread out accesses. Advancing the PC: The PCs were previously managed entirely by the CPU which had to know about PC semantics, try to figure out which dimension to increment the PC in, what to set NPC/NNPC, etc. These decisions are best left to the ISA in conjunction with the PC type itself. Because most of the information about how to increment the PC (mainly what type of instruction it refers to) is contained in the instruction object, a new advancePC virtual function was added to the StaticInst class. Subclasses provide an implementation that moves around the right element of the PC with a minimal amount of decision making. In ISAs like Alpha, the instructions always simply assign NPC to PC without having to worry about micropcs, nnpcs, etc. The added cost of a virtual function call should be outweighed by not having to figure out as much about what to do with the PCs and mucking around with the extra elements. One drawback of making the StaticInsts advance the PC is that you have to actually have one to advance the PC. This would, superficially, seem to require decoding an instruction before fetch could advance. This is, as far as I can tell, realistic. fetch would advance through memory addresses, not PCs, perhaps predicting new memory addresses using existing ones. More sophisticated decisions about control flow would be made later on, after the instruction was decoded, and handed back to fetch. If branching needs to happen, some amount of decoding needs to happen to see that it's a branch, what the target is, etc. This could get a little more complicated if that gets done by the predecoder, but I'm choosing to ignore that for now. Variable length instructions: To handle variable length instructions in x86 and ARM, the predecoder now takes in the current PC by reference to the getExtMachInst function. It can modify the PC however it needs to (by setting NPC to be the PC + instruction length, for instance). This could be improved since the CPU doesn't know if the PC was modified and always has to write it back. ISA parser: To support the new API, all PC related operand types were removed from the parser and replaced with a PCState type. There are two warts on this implementation. First, as with all the other operand types, the PCState still has to have a valid operand type even though it doesn't use it. Second, using syntax like PCS.npc(target) doesn't work for two reasons, this looks like the syntax for operand type overriding, and the parser can't figure out if you're reading or writing. Instructions that use the PCS operand (which I've consistently called it) need to first read it into a local variable, manipulate it, and then write it back out. Return address stack: The return address stack needed a little extra help because, in the presence of branch delay slots, it has to merge together elements of the return PC and the call PC. To handle that, a buildRetPC utility function was added. There are basically only two versions in all the ISAs, but it didn't seem short enough to put into the generic ISA directory. Also, the branch predictor code in O3 and InOrder were adjusted so that they always store the PC of the actual call instruction in the RAS, not the next PC. If the call instruction is a microop, the next PC refers to the next microop in the same macroop which is probably not desirable. The buildRetPC function advances the PC intelligently to the next macroop (in an ISA specific way) so that that case works. Change in stats: There were no change in stats except in MIPS and SPARC in the O3 model. MIPS runs in about 9% fewer ticks. SPARC runs with 30%-50% fewer ticks, which could likely be improved further by setting call/return instruction flags and taking advantage of the RAS. TODO: Add != operators to the PCState classes, defined trivially to be !(a==b). Smooth out places where PCs are split apart, passed around, and put back together later. I think this might happen in SPARC's fault code. Add ISA specific constructors that allow setting PC elements without calling a bunch of accessors. Try to eliminate the need for the branching() function. Factor out Alpha's PAL mode pc bit into a separate flag field, and eliminate places where it's blindly masked out or tested in the PC.
2010-10-31 08:07:20 +01:00
inst->setPredTarg(target);
break;
}
}
}
// If we didn't process all instructions, then we will need to block
// and put all those instructions into the skid buffer.
if (!insts_to_decode.empty()) {
block(tid);
}
Update to make multiple instruction issue and different latencies work. Also change to ref counted DynInst. SConscript: Add branch predictor, BTB, load store queue, and storesets. arch/isa_parser.py: Specify the template parameter for AlphaDynInst base/traceflags.py: Add load store queue, store set, and mem dependence unit to the list of trace flags. cpu/base_dyn_inst.cc: Change formating, add in debug statement. cpu/base_dyn_inst.hh: Change DynInst to be RefCounted, add flag to clear whether or not this instruction can commit. This is likely to be removed in the future. cpu/beta_cpu/alpha_dyn_inst.cc: AlphaDynInst has been changed to be templated, so now this CC file is just used to force instantiations of AlphaDynInst. cpu/beta_cpu/alpha_dyn_inst.hh: Changed AlphaDynInst to be templated on Impl. Removed some unnecessary functions. cpu/beta_cpu/alpha_full_cpu.cc: AlphaFullCPU has been changed to be templated, so this CC file is now just used to force instantation of AlphaFullCPU. cpu/beta_cpu/alpha_full_cpu.hh: Change AlphaFullCPU to be templated on Impl. cpu/beta_cpu/alpha_impl.hh: Update it to reflect AlphaDynInst and AlphaFullCPU being templated on Impl. Also removed time buffers from here, as they are really a part of the CPU and are thus in the CPU policy now. cpu/beta_cpu/alpha_params.hh: Make AlphaSimpleParams inherit from the BaseFullCPU so that it doesn't need to specifically declare any parameters that are already in the BaseFullCPU. cpu/beta_cpu/comm.hh: Changed the structure of the time buffer communication structs. Now they include the size of the packet of instructions it is sending. Added some parameters to the backwards communication struct, mainly for squashing. cpu/beta_cpu/commit.hh: Update typenames to reflect change in location of time buffer structs. Update DynInst to DynInstPtr (it is refcounted now). cpu/beta_cpu/commit_impl.hh: Formatting changes mainly. Also sends back proper information on branch mispredicts so that the bpred unit can update itself. Updated behavior for non-speculative instructions (stores, any other non-spec instructions): once they reach the head of the ROB, the ROB signals back to the IQ that it can go ahead and issue the non-speculative instruction. The instruction itself is updated so that commit won't try to commit it again until it is done executing. cpu/beta_cpu/cpu_policy.hh: Added branch prediction unit, mem dependence prediction unit, load store queue. Moved time buffer structs from AlphaSimpleImpl to here. cpu/beta_cpu/decode.hh: Changed typedefs to reflect change in location of time buffer structs and also the change from DynInst to ref counted DynInstPtr. cpu/beta_cpu/decode_impl.hh: Continues to buffer instructions even while unblocking now. Changed how it loops through groups of instructions so it can properly block during the middle of a group of instructions. cpu/beta_cpu/fetch.hh: Changed typedefs to reflect change in location of time buffer structs and the change to ref counted DynInsts. Also added in branch brediction unit. cpu/beta_cpu/fetch_impl.hh: Add in branch prediction. Changed how fetch checks inputs and its current state to make for easier logic. cpu/beta_cpu/free_list.cc: Changed int regs and float regs to logically use one flat namespace. Future change will be moving them to a single scoreboard to conserve space. cpu/beta_cpu/free_list.hh: Mostly debugging statements. Might be removed for performance in future. cpu/beta_cpu/full_cpu.cc: Added in some debugging statements. Updated BaseFullCPU to take a params object. cpu/beta_cpu/full_cpu.hh: Added params class within BaseCPU that other param classes will be able to inherit from. Updated typedefs to reflect change in location of time buffer structs and ref counted DynInst. cpu/beta_cpu/iew.hh: Updated typedefs to reflect change in location of time buffer structs and use of ref counted DynInsts. cpu/beta_cpu/iew_impl.hh: Added in load store queue, updated iew to be able to execute non- speculative instructions, instead of having them execute in commit. cpu/beta_cpu/inst_queue.hh: Updated change to ref counted DynInsts. Changed inst queue to hold non-speculative instructions as well, which are issued only when commit signals backwards that a nonspeculative instruction is at the head of the ROB. cpu/beta_cpu/inst_queue_impl.hh: Updated to allow for non-speculative instructions to be in the inst queue. Also added some debug functions. cpu/beta_cpu/regfile.hh: Added debugging statements, changed formatting. cpu/beta_cpu/rename.hh: Updated typedefs, added some functions to clean up code. cpu/beta_cpu/rename_impl.hh: Moved some code into functions to make it easier to read. cpu/beta_cpu/rename_map.cc: Changed int and float reg behavior to use a single flat namespace. In the future, the rename maps can be combined to a single rename map to save space. cpu/beta_cpu/rename_map.hh: Added destructor. cpu/beta_cpu/rob.hh: Updated it with change from DynInst to ref counted DynInst. cpu/beta_cpu/rob_impl.hh: Formatting, updated to use ref counted DynInst. cpu/static_inst.hh: Updated forward declaration for AlphaDynInst now that it is templated. --HG-- extra : convert_revision : 1045f240ee9b6a4bd368e1806aca029ebbdc6dd3
2004-09-23 20:06:03 +02:00
// Record that decode has written to the time buffer for activity
// tracking.
if (toRenameIndex) {
wroteToTimeBuffer = true;
}
}