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Split Alpha ISA description into multiple files (thanks to Gabe's include feature!). arch/alpha/isa/main.isa: Split out into multiple .isa files. --HG-- extra : convert_revision : 30d8edf74ea194d4a208febf1e66edc72a7dbd5d
2006-02-10 05:02:38 +01:00
// -*- mode:c++ -*-
// Copyright (c) 2003-2005 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.
Updated Authors from bk prs info --HG-- extra : convert_revision : 77f475b156d81c03a2811818fa23593d5615c685
2006-06-01 01:26:56 +02:00
//
// Authors: Steve Reinhardt
Split Alpha ISA description into multiple files (thanks to Gabe's include feature!). arch/alpha/isa/main.isa: Split out into multiple .isa files. --HG-- extra : convert_revision : 30d8edf74ea194d4a208febf1e66edc72a7dbd5d
2006-02-10 05:02:38 +01:00
Remove authors from copyright. --HG-- extra : convert_revision : 5daba0ab70b4e6d7213bad6aedcb47a0fe56031d
2006-05-29 05:26:15 +02:00
////////////////////////////////////////////////////////////////////
//
// Control transfer instructions
//
Split Alpha ISA description into multiple files (thanks to Gabe's include feature!). arch/alpha/isa/main.isa: Split out into multiple .isa files. --HG-- extra : convert_revision : 30d8edf74ea194d4a208febf1e66edc72a7dbd5d
2006-02-10 05:02:38 +01:00
output header {{
/**
* Base class for instructions whose disassembly is not purely a
* function of the machine instruction (i.e., it depends on the
* PC). This class overrides the disassemble() method to check
* the PC and symbol table values before re-using a cached
* disassembly string. This is necessary for branches and jumps,
* where the disassembly string includes the target address (which
* may depend on the PC and/or symbol table).
*/
class PCDependentDisassembly : public AlphaStaticInst
{
protected:
/// Cached program counter from last disassembly
mutable Addr cachedPC;
/// Cached symbol table pointer from last disassembly
mutable const SymbolTable *cachedSymtab;
/// Constructor
Changes to support automatic renaming of the shadow registers at decode time. This requires using an ExtMachInst (uint64_t) instead of the normal MachInst; the ExtMachInst is packed with extra decode context information. In the case of Alpha, the PAL mode is included. The shadow registers are folded into the normal integer registers to ease renaming indexing. Include the removed Opcdec class of instructions for faulting when a pal mode only instruction is decoded in non-pal mode. arch/alpha/ev5.cc: Changes to automatically map the shadow registers if the instruction is in PAL mode. arch/alpha/isa/branch.isa: arch/alpha/isa/decoder.isa: arch/alpha/isa/fp.isa: arch/alpha/isa/int.isa: arch/alpha/isa/mem.isa: arch/alpha/isa/pal.isa: arch/alpha/isa/unimp.isa: Changes for automatically using the shadow registers. Now instructions must decode based on an ExtMachInst, which is a MachInst with any decode context information concatenated onto the higher order bits. arch/alpha/isa/main.isa: Changes for automatically using the shadow registers. Now instructions must decode based on an ExtMachInst, which is a MachInst with any decode context information concatenated onto the higher order bits. The decoder (for Alpha) uses the 32nd bit in order to determine if the machine is in PAL mode. If it is, then it refers to the reg_redir table to determine the true index of the register it is using. Also include the opcdec instruction definition. arch/alpha/isa_traits.hh: Define ExtMachInst type that is used by the static inst in order to decode the instruction, given the context of being in pal mode or not. Redefine the number of Int registers, splitting it into NumIntArchRegs (32) and NumIntRegs (32 + 8 shadow registers). Change the dependence tags to reflect the integer registers include the 8 shadow registers. Define function to make an ExtMachInst. Currently it is somewhat specific to Alpha; in the future it must be decided to make this more generic and possibly slower, or leave it specific to each architecture and ifdef it within the CPU. arch/isa_parser.py: Have static insts decode on the ExtMachInst. base/remote_gdb.cc: Support the automatic remapping of shadow registers. Remote GDB must now look at the PC being read in order to tell if it should use the normal register indices or the shadow register indices. cpu/o3/regfile.hh: Comment out the pal registers; they are now a part of the integer registers. cpu/simple/cpu.cc: Create an ExtMachInst to decode on, based on the normal MachInst and the PC of the instructoin. cpu/static_inst.hh: Change from MachInst to ExtMachInst to support shadow register renaming. --HG-- extra : convert_revision : 1d23eabf735e297068e1917445a6348e9f8c88d5
2006-03-03 21:28:25 +01:00
PCDependentDisassembly(const char *mnem, ExtMachInst _machInst,
Split Alpha ISA description into multiple files (thanks to Gabe's include feature!). arch/alpha/isa/main.isa: Split out into multiple .isa files. --HG-- extra : convert_revision : 30d8edf74ea194d4a208febf1e66edc72a7dbd5d
2006-02-10 05:02:38 +01:00
OpClass __opClass)
: AlphaStaticInst(mnem, _machInst, __opClass),
cachedPC(0), cachedSymtab(0)
{
}
const std::string &
disassemble(Addr pc, const SymbolTable *symtab) const;
};
/**
* Base class for branches (PC-relative control transfers),
* conditional or unconditional.
*/
class Branch : public PCDependentDisassembly
{
protected:
/// Displacement to target address (signed).
int32_t disp;
/// Constructor.
Changes to support automatic renaming of the shadow registers at decode time. This requires using an ExtMachInst (uint64_t) instead of the normal MachInst; the ExtMachInst is packed with extra decode context information. In the case of Alpha, the PAL mode is included. The shadow registers are folded into the normal integer registers to ease renaming indexing. Include the removed Opcdec class of instructions for faulting when a pal mode only instruction is decoded in non-pal mode. arch/alpha/ev5.cc: Changes to automatically map the shadow registers if the instruction is in PAL mode. arch/alpha/isa/branch.isa: arch/alpha/isa/decoder.isa: arch/alpha/isa/fp.isa: arch/alpha/isa/int.isa: arch/alpha/isa/mem.isa: arch/alpha/isa/pal.isa: arch/alpha/isa/unimp.isa: Changes for automatically using the shadow registers. Now instructions must decode based on an ExtMachInst, which is a MachInst with any decode context information concatenated onto the higher order bits. arch/alpha/isa/main.isa: Changes for automatically using the shadow registers. Now instructions must decode based on an ExtMachInst, which is a MachInst with any decode context information concatenated onto the higher order bits. The decoder (for Alpha) uses the 32nd bit in order to determine if the machine is in PAL mode. If it is, then it refers to the reg_redir table to determine the true index of the register it is using. Also include the opcdec instruction definition. arch/alpha/isa_traits.hh: Define ExtMachInst type that is used by the static inst in order to decode the instruction, given the context of being in pal mode or not. Redefine the number of Int registers, splitting it into NumIntArchRegs (32) and NumIntRegs (32 + 8 shadow registers). Change the dependence tags to reflect the integer registers include the 8 shadow registers. Define function to make an ExtMachInst. Currently it is somewhat specific to Alpha; in the future it must be decided to make this more generic and possibly slower, or leave it specific to each architecture and ifdef it within the CPU. arch/isa_parser.py: Have static insts decode on the ExtMachInst. base/remote_gdb.cc: Support the automatic remapping of shadow registers. Remote GDB must now look at the PC being read in order to tell if it should use the normal register indices or the shadow register indices. cpu/o3/regfile.hh: Comment out the pal registers; they are now a part of the integer registers. cpu/simple/cpu.cc: Create an ExtMachInst to decode on, based on the normal MachInst and the PC of the instructoin. cpu/static_inst.hh: Change from MachInst to ExtMachInst to support shadow register renaming. --HG-- extra : convert_revision : 1d23eabf735e297068e1917445a6348e9f8c88d5
2006-03-03 21:28:25 +01:00
Branch(const char *mnem, ExtMachInst _machInst, OpClass __opClass)
Split Alpha ISA description into multiple files (thanks to Gabe's include feature!). arch/alpha/isa/main.isa: Split out into multiple .isa files. --HG-- extra : convert_revision : 30d8edf74ea194d4a208febf1e66edc72a7dbd5d
2006-02-10 05:02:38 +01:00
: PCDependentDisassembly(mnem, _machInst, __opClass),
disp(BRDISP << 2)
{
}
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
AlphaISA::PCState branchTarget(const AlphaISA::PCState &branchPC) const;
Split Alpha ISA description into multiple files (thanks to Gabe's include feature!). arch/alpha/isa/main.isa: Split out into multiple .isa files. --HG-- extra : convert_revision : 30d8edf74ea194d4a208febf1e66edc72a7dbd5d
2006-02-10 05:02:38 +01:00
scons: Add warning for overloaded virtual functions A derived function with a different signature than a base class function will result in the base class function of the same name being hidden. The parameter list and return type for the member function in the derived class must match those of the member function in the base class, otherwise the function in the derived class will hide the function in the base class and no polymorphic behaviour will occur. This patch addresses these warnings by ensuring a unique function name to avoid (unintentionally) hiding any functions.
2013-02-19 11:56:06 +01:00
/// Explicitly import the otherwise hidden branchTarget
using StaticInst::branchTarget;
Split Alpha ISA description into multiple files (thanks to Gabe's include feature!). arch/alpha/isa/main.isa: Split out into multiple .isa files. --HG-- extra : convert_revision : 30d8edf74ea194d4a208febf1e66edc72a7dbd5d
2006-02-10 05:02:38 +01:00
std::string
generateDisassembly(Addr pc, const SymbolTable *symtab) const;
};
/**
* Base class for jumps (register-indirect control transfers). In
* the Alpha ISA, these are always unconditional.
*/
class Jump : public PCDependentDisassembly
{
protected:
/// Displacement to target address (signed).
int32_t disp;
public:
/// Constructor
Changes to support automatic renaming of the shadow registers at decode time. This requires using an ExtMachInst (uint64_t) instead of the normal MachInst; the ExtMachInst is packed with extra decode context information. In the case of Alpha, the PAL mode is included. The shadow registers are folded into the normal integer registers to ease renaming indexing. Include the removed Opcdec class of instructions for faulting when a pal mode only instruction is decoded in non-pal mode. arch/alpha/ev5.cc: Changes to automatically map the shadow registers if the instruction is in PAL mode. arch/alpha/isa/branch.isa: arch/alpha/isa/decoder.isa: arch/alpha/isa/fp.isa: arch/alpha/isa/int.isa: arch/alpha/isa/mem.isa: arch/alpha/isa/pal.isa: arch/alpha/isa/unimp.isa: Changes for automatically using the shadow registers. Now instructions must decode based on an ExtMachInst, which is a MachInst with any decode context information concatenated onto the higher order bits. arch/alpha/isa/main.isa: Changes for automatically using the shadow registers. Now instructions must decode based on an ExtMachInst, which is a MachInst with any decode context information concatenated onto the higher order bits. The decoder (for Alpha) uses the 32nd bit in order to determine if the machine is in PAL mode. If it is, then it refers to the reg_redir table to determine the true index of the register it is using. Also include the opcdec instruction definition. arch/alpha/isa_traits.hh: Define ExtMachInst type that is used by the static inst in order to decode the instruction, given the context of being in pal mode or not. Redefine the number of Int registers, splitting it into NumIntArchRegs (32) and NumIntRegs (32 + 8 shadow registers). Change the dependence tags to reflect the integer registers include the 8 shadow registers. Define function to make an ExtMachInst. Currently it is somewhat specific to Alpha; in the future it must be decided to make this more generic and possibly slower, or leave it specific to each architecture and ifdef it within the CPU. arch/isa_parser.py: Have static insts decode on the ExtMachInst. base/remote_gdb.cc: Support the automatic remapping of shadow registers. Remote GDB must now look at the PC being read in order to tell if it should use the normal register indices or the shadow register indices. cpu/o3/regfile.hh: Comment out the pal registers; they are now a part of the integer registers. cpu/simple/cpu.cc: Create an ExtMachInst to decode on, based on the normal MachInst and the PC of the instructoin. cpu/static_inst.hh: Change from MachInst to ExtMachInst to support shadow register renaming. --HG-- extra : convert_revision : 1d23eabf735e297068e1917445a6348e9f8c88d5
2006-03-03 21:28:25 +01:00
Jump(const char *mnem, ExtMachInst _machInst, OpClass __opClass)
Split Alpha ISA description into multiple files (thanks to Gabe's include feature!). arch/alpha/isa/main.isa: Split out into multiple .isa files. --HG-- extra : convert_revision : 30d8edf74ea194d4a208febf1e66edc72a7dbd5d
2006-02-10 05:02:38 +01:00
: PCDependentDisassembly(mnem, _machInst, __opClass),
disp(BRDISP)
{
}
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
AlphaISA::PCState branchTarget(ThreadContext *tc) const;
Split Alpha ISA description into multiple files (thanks to Gabe's include feature!). arch/alpha/isa/main.isa: Split out into multiple .isa files. --HG-- extra : convert_revision : 30d8edf74ea194d4a208febf1e66edc72a7dbd5d
2006-02-10 05:02:38 +01:00
scons: Add warning for overloaded virtual functions A derived function with a different signature than a base class function will result in the base class function of the same name being hidden. The parameter list and return type for the member function in the derived class must match those of the member function in the base class, otherwise the function in the derived class will hide the function in the base class and no polymorphic behaviour will occur. This patch addresses these warnings by ensuring a unique function name to avoid (unintentionally) hiding any functions.
2013-02-19 11:56:06 +01:00
/// Explicitly import the otherwise hidden branchTarget
using StaticInst::branchTarget;
Split Alpha ISA description into multiple files (thanks to Gabe's include feature!). arch/alpha/isa/main.isa: Split out into multiple .isa files. --HG-- extra : convert_revision : 30d8edf74ea194d4a208febf1e66edc72a7dbd5d
2006-02-10 05:02:38 +01:00
std::string
generateDisassembly(Addr pc, const SymbolTable *symtab) const;
};
}};
output decoder {{
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
AlphaISA::PCState
Branch::branchTarget(const AlphaISA::PCState &branchPC) const
Split Alpha ISA description into multiple files (thanks to Gabe's include feature!). arch/alpha/isa/main.isa: Split out into multiple .isa files. --HG-- extra : convert_revision : 30d8edf74ea194d4a208febf1e66edc72a7dbd5d
2006-02-10 05:02:38 +01:00
{
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
return branchPC.pc() + 4 + disp;
Split Alpha ISA description into multiple files (thanks to Gabe's include feature!). arch/alpha/isa/main.isa: Split out into multiple .isa files. --HG-- extra : convert_revision : 30d8edf74ea194d4a208febf1e66edc72a7dbd5d
2006-02-10 05:02:38 +01:00
}
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
AlphaISA::PCState
Change ExecContext to ThreadContext. This is being renamed to differentiate between the interface used objects outside of the CPU, and the interface used by the ISA. ThreadContext is used by objects outside of the CPU and is specifically defined in thread_context.hh. ExecContext is more implicit, and is defined by files such as base_dyn_inst.hh or cpu/simple/base.hh. Further renames/reorganization will be coming shortly; what is currently CPUExecContext (the old ExecContext from m5) will be renamed to SimpleThread or something similar. src/arch/alpha/arguments.cc: src/arch/alpha/arguments.hh: src/arch/alpha/ev5.cc: src/arch/alpha/faults.cc: src/arch/alpha/faults.hh: src/arch/alpha/freebsd/system.cc: src/arch/alpha/freebsd/system.hh: src/arch/alpha/isa/branch.isa: src/arch/alpha/isa/decoder.isa: src/arch/alpha/isa/main.isa: src/arch/alpha/linux/process.cc: src/arch/alpha/linux/system.cc: src/arch/alpha/linux/system.hh: src/arch/alpha/linux/threadinfo.hh: src/arch/alpha/process.cc: src/arch/alpha/regfile.hh: src/arch/alpha/stacktrace.cc: src/arch/alpha/stacktrace.hh: src/arch/alpha/tlb.cc: src/arch/alpha/tlb.hh: src/arch/alpha/tru64/process.cc: src/arch/alpha/tru64/system.cc: src/arch/alpha/tru64/system.hh: src/arch/alpha/utility.hh: src/arch/alpha/vtophys.cc: src/arch/alpha/vtophys.hh: src/arch/mips/faults.cc: src/arch/mips/faults.hh: src/arch/mips/isa_traits.cc: src/arch/mips/isa_traits.hh: src/arch/mips/linux/process.cc: src/arch/mips/process.cc: src/arch/mips/regfile/float_regfile.hh: src/arch/mips/regfile/int_regfile.hh: src/arch/mips/regfile/misc_regfile.hh: src/arch/mips/regfile/regfile.hh: src/arch/mips/stacktrace.hh: src/arch/sparc/faults.cc: src/arch/sparc/faults.hh: src/arch/sparc/isa_traits.hh: src/arch/sparc/linux/process.cc: src/arch/sparc/linux/process.hh: src/arch/sparc/process.cc: src/arch/sparc/regfile.hh: src/arch/sparc/solaris/process.cc: src/arch/sparc/stacktrace.hh: src/arch/sparc/ua2005.cc: src/arch/sparc/utility.hh: src/arch/sparc/vtophys.cc: src/arch/sparc/vtophys.hh: src/base/remote_gdb.cc: src/base/remote_gdb.hh: src/cpu/base.cc: src/cpu/base.hh: src/cpu/base_dyn_inst.hh: src/cpu/checker/cpu.cc: src/cpu/checker/cpu.hh: src/cpu/checker/exec_context.hh: src/cpu/cpu_exec_context.cc: src/cpu/cpu_exec_context.hh: src/cpu/cpuevent.cc: src/cpu/cpuevent.hh: src/cpu/exetrace.hh: src/cpu/intr_control.cc: src/cpu/memtest/memtest.hh: src/cpu/o3/alpha_cpu.hh: src/cpu/o3/alpha_cpu_impl.hh: src/cpu/o3/alpha_dyn_inst_impl.hh: src/cpu/o3/commit.hh: src/cpu/o3/commit_impl.hh: src/cpu/o3/cpu.cc: src/cpu/o3/cpu.hh: src/cpu/o3/fetch_impl.hh: src/cpu/o3/regfile.hh: src/cpu/o3/thread_state.hh: src/cpu/ozone/back_end.hh: src/cpu/ozone/cpu.hh: src/cpu/ozone/cpu_impl.hh: src/cpu/ozone/front_end.hh: src/cpu/ozone/front_end_impl.hh: src/cpu/ozone/inorder_back_end.hh: src/cpu/ozone/lw_back_end.hh: src/cpu/ozone/lw_back_end_impl.hh: src/cpu/ozone/lw_lsq.hh: src/cpu/ozone/lw_lsq_impl.hh: src/cpu/ozone/thread_state.hh: src/cpu/pc_event.cc: src/cpu/pc_event.hh: src/cpu/profile.cc: src/cpu/profile.hh: src/cpu/quiesce_event.cc: src/cpu/quiesce_event.hh: src/cpu/simple/atomic.cc: src/cpu/simple/base.cc: src/cpu/simple/base.hh: src/cpu/simple/timing.cc: src/cpu/static_inst.cc: src/cpu/static_inst.hh: src/cpu/thread_state.hh: src/dev/alpha_console.cc: src/dev/ns_gige.cc: src/dev/sinic.cc: src/dev/tsunami_cchip.cc: src/kern/kernel_stats.cc: src/kern/kernel_stats.hh: src/kern/linux/events.cc: src/kern/linux/events.hh: src/kern/system_events.cc: src/kern/system_events.hh: src/kern/tru64/dump_mbuf.cc: src/kern/tru64/tru64.hh: src/kern/tru64/tru64_events.cc: src/kern/tru64/tru64_events.hh: src/mem/vport.cc: src/mem/vport.hh: src/sim/faults.cc: src/sim/faults.hh: src/sim/process.cc: src/sim/process.hh: src/sim/pseudo_inst.cc: src/sim/pseudo_inst.hh: src/sim/syscall_emul.cc: src/sim/syscall_emul.hh: src/sim/system.cc: src/cpu/thread_context.hh: src/sim/system.hh: src/sim/vptr.hh: Change ExecContext to ThreadContext. --HG-- rename : src/cpu/exec_context.hh => src/cpu/thread_context.hh extra : convert_revision : 108bb97d15a114a565a2a6a23faa554f4e2fd77e
2006-06-06 23:32:21 +02:00
Jump::branchTarget(ThreadContext *tc) const
Split Alpha ISA description into multiple files (thanks to Gabe's include feature!). arch/alpha/isa/main.isa: Split out into multiple .isa files. --HG-- extra : convert_revision : 30d8edf74ea194d4a208febf1e66edc72a7dbd5d
2006-02-10 05:02:38 +01:00
{
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
PCState pc = tc->pcState();
Change ExecContext to ThreadContext. This is being renamed to differentiate between the interface used objects outside of the CPU, and the interface used by the ISA. ThreadContext is used by objects outside of the CPU and is specifically defined in thread_context.hh. ExecContext is more implicit, and is defined by files such as base_dyn_inst.hh or cpu/simple/base.hh. Further renames/reorganization will be coming shortly; what is currently CPUExecContext (the old ExecContext from m5) will be renamed to SimpleThread or something similar. src/arch/alpha/arguments.cc: src/arch/alpha/arguments.hh: src/arch/alpha/ev5.cc: src/arch/alpha/faults.cc: src/arch/alpha/faults.hh: src/arch/alpha/freebsd/system.cc: src/arch/alpha/freebsd/system.hh: src/arch/alpha/isa/branch.isa: src/arch/alpha/isa/decoder.isa: src/arch/alpha/isa/main.isa: src/arch/alpha/linux/process.cc: src/arch/alpha/linux/system.cc: src/arch/alpha/linux/system.hh: src/arch/alpha/linux/threadinfo.hh: src/arch/alpha/process.cc: src/arch/alpha/regfile.hh: src/arch/alpha/stacktrace.cc: src/arch/alpha/stacktrace.hh: src/arch/alpha/tlb.cc: src/arch/alpha/tlb.hh: src/arch/alpha/tru64/process.cc: src/arch/alpha/tru64/system.cc: src/arch/alpha/tru64/system.hh: src/arch/alpha/utility.hh: src/arch/alpha/vtophys.cc: src/arch/alpha/vtophys.hh: src/arch/mips/faults.cc: src/arch/mips/faults.hh: src/arch/mips/isa_traits.cc: src/arch/mips/isa_traits.hh: src/arch/mips/linux/process.cc: src/arch/mips/process.cc: src/arch/mips/regfile/float_regfile.hh: src/arch/mips/regfile/int_regfile.hh: src/arch/mips/regfile/misc_regfile.hh: src/arch/mips/regfile/regfile.hh: src/arch/mips/stacktrace.hh: src/arch/sparc/faults.cc: src/arch/sparc/faults.hh: src/arch/sparc/isa_traits.hh: src/arch/sparc/linux/process.cc: src/arch/sparc/linux/process.hh: src/arch/sparc/process.cc: src/arch/sparc/regfile.hh: src/arch/sparc/solaris/process.cc: src/arch/sparc/stacktrace.hh: src/arch/sparc/ua2005.cc: src/arch/sparc/utility.hh: src/arch/sparc/vtophys.cc: src/arch/sparc/vtophys.hh: src/base/remote_gdb.cc: src/base/remote_gdb.hh: src/cpu/base.cc: src/cpu/base.hh: src/cpu/base_dyn_inst.hh: src/cpu/checker/cpu.cc: src/cpu/checker/cpu.hh: src/cpu/checker/exec_context.hh: src/cpu/cpu_exec_context.cc: src/cpu/cpu_exec_context.hh: src/cpu/cpuevent.cc: src/cpu/cpuevent.hh: src/cpu/exetrace.hh: src/cpu/intr_control.cc: src/cpu/memtest/memtest.hh: src/cpu/o3/alpha_cpu.hh: src/cpu/o3/alpha_cpu_impl.hh: src/cpu/o3/alpha_dyn_inst_impl.hh: src/cpu/o3/commit.hh: src/cpu/o3/commit_impl.hh: src/cpu/o3/cpu.cc: src/cpu/o3/cpu.hh: src/cpu/o3/fetch_impl.hh: src/cpu/o3/regfile.hh: src/cpu/o3/thread_state.hh: src/cpu/ozone/back_end.hh: src/cpu/ozone/cpu.hh: src/cpu/ozone/cpu_impl.hh: src/cpu/ozone/front_end.hh: src/cpu/ozone/front_end_impl.hh: src/cpu/ozone/inorder_back_end.hh: src/cpu/ozone/lw_back_end.hh: src/cpu/ozone/lw_back_end_impl.hh: src/cpu/ozone/lw_lsq.hh: src/cpu/ozone/lw_lsq_impl.hh: src/cpu/ozone/thread_state.hh: src/cpu/pc_event.cc: src/cpu/pc_event.hh: src/cpu/profile.cc: src/cpu/profile.hh: src/cpu/quiesce_event.cc: src/cpu/quiesce_event.hh: src/cpu/simple/atomic.cc: src/cpu/simple/base.cc: src/cpu/simple/base.hh: src/cpu/simple/timing.cc: src/cpu/static_inst.cc: src/cpu/static_inst.hh: src/cpu/thread_state.hh: src/dev/alpha_console.cc: src/dev/ns_gige.cc: src/dev/sinic.cc: src/dev/tsunami_cchip.cc: src/kern/kernel_stats.cc: src/kern/kernel_stats.hh: src/kern/linux/events.cc: src/kern/linux/events.hh: src/kern/system_events.cc: src/kern/system_events.hh: src/kern/tru64/dump_mbuf.cc: src/kern/tru64/tru64.hh: src/kern/tru64/tru64_events.cc: src/kern/tru64/tru64_events.hh: src/mem/vport.cc: src/mem/vport.hh: src/sim/faults.cc: src/sim/faults.hh: src/sim/process.cc: src/sim/process.hh: src/sim/pseudo_inst.cc: src/sim/pseudo_inst.hh: src/sim/syscall_emul.cc: src/sim/syscall_emul.hh: src/sim/system.cc: src/cpu/thread_context.hh: src/sim/system.hh: src/sim/vptr.hh: Change ExecContext to ThreadContext. --HG-- rename : src/cpu/exec_context.hh => src/cpu/thread_context.hh extra : convert_revision : 108bb97d15a114a565a2a6a23faa554f4e2fd77e
2006-06-06 23:32:21 +02:00
uint64_t Rb = tc->readIntReg(_srcRegIdx[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
pc.set((Rb & ~3) | (pc.pc() & 1));
return pc;
Split Alpha ISA description into multiple files (thanks to Gabe's include feature!). arch/alpha/isa/main.isa: Split out into multiple .isa files. --HG-- extra : convert_revision : 30d8edf74ea194d4a208febf1e66edc72a7dbd5d
2006-02-10 05:02:38 +01:00
}
const std::string &
PCDependentDisassembly::disassemble(Addr pc,
const SymbolTable *symtab) const
{
if (!cachedDisassembly ||
pc != cachedPC || symtab != cachedSymtab)
{
if (cachedDisassembly)
delete cachedDisassembly;
cachedDisassembly =
new std::string(generateDisassembly(pc, symtab));
cachedPC = pc;
cachedSymtab = symtab;
}
return *cachedDisassembly;
}
std::string
Branch::generateDisassembly(Addr pc, const SymbolTable *symtab) const
{
std::stringstream ss;
ccprintf(ss, "%-10s ", mnemonic);
// There's only one register arg (RA), but it could be
// either a source (the condition for conditional
// branches) or a destination (the link reg for
// unconditional branches)
if (_numSrcRegs > 0) {
printReg(ss, _srcRegIdx[0]);
ss << ",";
}
else if (_numDestRegs > 0) {
printReg(ss, _destRegIdx[0]);
ss << ",";
}
#ifdef SS_COMPATIBLE_DISASSEMBLY
if (_numSrcRegs == 0 && _numDestRegs == 0) {
printReg(ss, 31);
ss << ",";
}
#endif
Addr target = pc + 4 + disp;
std::string str;
if (symtab && symtab->findSymbol(target, str))
ss << str;
else
ccprintf(ss, "0x%x", target);
return ss.str();
}
std::string
Jump::generateDisassembly(Addr pc, const SymbolTable *symtab) const
{
std::stringstream ss;
ccprintf(ss, "%-10s ", mnemonic);
#ifdef SS_COMPATIBLE_DISASSEMBLY
if (_numDestRegs == 0) {
printReg(ss, 31);
ss << ",";
}
#endif
if (_numDestRegs > 0) {
printReg(ss, _destRegIdx[0]);
ss << ",";
}
ccprintf(ss, "(r%d)", RB);
return ss.str();
}
}};
def template JumpOrBranchDecode {{
return (RA == 31)
Changes to untemplate StaticInst and StaticInstPtr, change the isa to a namespace instead of a class, an improvement to the architecture specific header file selection system, and fixed up a few include paths. arch/alpha/alpha_linux_process.cc: Added using directive for AlphaISA namespace arch/alpha/alpha_memory.hh: arch/alpha/isa/branch.isa: cpu/pc_event.hh: Added typedefs for Addr arch/alpha/alpha_tru64_process.cc: arch/alpha/arguments.cc: Added using directive for AlphaISA arch/alpha/ev5.hh: Added an include of arch/alpha/isa_traits.hh, and a using directive for the AlphaISA namespace. arch/alpha/faults.hh: Added a typedef for the Addr type, and changed the formatting of the faults slightly. arch/alpha/isa/main.isa: Untemplatized StaticInst, added a using for namespace AlphaISA to show up in decoder.cc and the exec.ccs, relocated makeNop to decoder.hh arch/alpha/isa/mem.isa: Untemplatized StaticInst and StaticInstPtr arch/alpha/isa/pal.isa: cpu/base_dyn_inst.cc: Untemplatized StaticInstPtr arch/alpha/isa_traits.hh: Changed variables to be externs instead of static since they are part of a namespace and not a class. arch/alpha/stacktrace.cc: Untemplatized StaticInstPtr, and added a using directive for AlphaISA. arch/alpha/stacktrace.hh: Added some typedefs for Addr and MachInst, and untemplatized StaticInstPtr arch/alpha/vtophys.cc: Added a using directive for AlphaISA arch/alpha/vtophys.hh: Added the AlphaISA namespace specifier where needed arch/isa_parser.py: Changed the placement of the definition of the decodeInst function to be outside the namespaceInst namespace. base/loader/object_file.hh: cpu/o3/bpred_unit.hh: Added a typedef for Addr base/loader/symtab.hh: Added a typedef for Addr, and added a TheISA to Addr in another typedef base/remote_gdb.cc: Added a using namespace TheISA, and untemplatized StaticInstPtr base/remote_gdb.hh: Added typedefs for Addr and MachInst cpu/base.cc: Added TheISA specifier to some variables exported from the isa. cpu/base.hh: Added a typedef for Addr, and TheISA to some variables from the ISA cpu/base_dyn_inst.hh: Untemplatized StaticInstPtr, and added TheISA specifier to some variables from the ISA. cpu/exec_context.hh: Added some typedefs for types from the isa, and added TheISA specifier to some variables from the isa cpu/exetrace.hh: Added typedefs for some types from the ISA, and untemplatized StaticInstPtr cpu/memtest/memtest.cc: cpu/o3/btb.cc: dev/baddev.cc: dev/ide_ctrl.cc: dev/ide_disk.cc: dev/isa_fake.cc: dev/ns_gige.cc: dev/pciconfigall.cc: dev/platform.cc: dev/sinic.cc: dev/uart8250.cc: kern/freebsd/freebsd_system.cc: kern/linux/linux_system.cc: kern/system_events.cc: kern/tru64/dump_mbuf.cc: kern/tru64/tru64_events.cc: sim/process.cc: sim/pseudo_inst.cc: sim/system.cc: Added using namespace TheISA cpu/memtest/memtest.hh: cpu/trace/opt_cpu.hh: cpu/trace/reader/itx_reader.hh: dev/ide_disk.hh: dev/pcidev.hh: dev/platform.hh: dev/tsunami.hh: sim/system.hh: sim/vptr.hh: Added typedef for Addr cpu/o3/2bit_local_pred.hh: Changed the include to use arch/isa_traits.hh instead of arch/alpha/isa_traits.hh. Added typedef for Addr cpu/o3/alpha_cpu.hh: Added typedefs for Addr and IntReg cpu/o3/alpha_cpu_impl.hh: Added this-> to setNextPC to fix a problem since it didn't depend on template parameters any more. Removed "typename" where it was no longer needed. cpu/o3/alpha_dyn_inst.hh: Cleaned up some typedefs, and untemplatized StaticInst cpu/o3/alpha_dyn_inst_impl.hh: untemplatized StaticInstPtr cpu/o3/alpha_impl.hh: Fixed up a typedef of MachInst cpu/o3/bpred_unit_impl.hh: Added a using TheISA::MachInst to a function cpu/o3/btb.hh: Changed an include from arch/alpha/isa_traits.hh to arch/isa_traits.hh, and added a typedef for Addr cpu/o3/commit.hh: Removed a typedef of Impl::ISA as ISA, since TheISA takes care of this now. cpu/o3/cpu.cc: Cleaned up namespace issues cpu/o3/cpu.hh: Cleaned up namespace usage cpu/o3/decode.hh: Removed typedef of ISA, and changed it to TheISA cpu/o3/fetch.hh: Fized up typedefs, and changed ISA to TheISA cpu/o3/free_list.hh: Changed include of arch/alpha/isa_traits.hh to arch/isa_traits.hh cpu/o3/iew.hh: Removed typedef of ISA cpu/o3/iew_impl.hh: Added TheISA namespace specifier to MachInst cpu/o3/ras.hh: Changed include from arch/alpha/isa_traits.hh to arch/isa_traits.hh, and added a typedef for Addr. cpu/o3/regfile.hh: Changed ISA to TheISA, and added some typedefs for Addr, IntReg, FloatReg, and MiscRegFile cpu/o3/rename.hh: Changed ISA to TheISA, and added a typedef for RegIndex cpu/o3/rename_map.hh: Added an include for arch/isa_traits.hh, and a typedef for RegIndex cpu/o3/rob.hh: Added a typedef for RegIndex cpu/o3/store_set.hh: cpu/o3/tournament_pred.hh: Changed an include of arch/alpha/isa_traits.hh to arch/isa_traits.hh, and added a typedef of Addr cpu/ozone/cpu.hh: Changed ISA into TheISA, and untemplatized StaticInst cpu/pc_event.cc: Added namespace specifier TheISA to Addr types cpu/profile.hh: kern/kernel_stats.hh: Added typedef for Addr, and untemplatized StaticInstPtr cpu/simple/cpu.cc: Changed using directive from LittleEndianGuest to AlphaISA, which will contain both namespaces. Added TheISA where needed, and untemplatized StaticInst cpu/simple/cpu.hh: Added a typedef for MachInst, and untemplatized StaticInst cpu/static_inst.cc: Untemplatized StaticInst cpu/static_inst.hh: Untemplatized StaticInst by using the TheISA namespace dev/alpha_console.cc: Added using namespace AlphaISA dev/simple_disk.hh: Added typedef for Addr and fixed up some formatting dev/sinicreg.hh: Added TheISA namespace specifier where needed dev/tsunami.cc: dev/tsunami_io.cc: dev/tsunami_pchip.cc: Added using namespace TheISA. It might be better for it to be AlphaISA dev/tsunami_cchip.cc: Added typedef for TheISA. It might be better for it to be AlphaISA kern/linux/aligned.hh: sim/pseudo_inst.hh: Added TheISA namespace specifier to Addr kern/linux/linux_threadinfo.hh: Added typedef for Addr, and TheISA namespace specifier to StackPointerReg kern/tru64/mbuf.hh: Added TheISA to Addr type in structs sim/process.hh: Added typedefs of Addr, RegFile, and MachInst sim/syscall_emul.cc: Added using namespace TheISA, and a cast of VMPageSize to the int type sim/syscall_emul.hh: Added typecast for Addr, and TheISA namespace specifier for where needed --HG-- extra : convert_revision : 91d4f6ca33a73b21c1f1771d74bfdea3b80eff45
2006-02-19 08:34:37 +01:00
? (StaticInst *)new %(class_name)s(machInst)
: (StaticInst *)new %(class_name)sAndLink(machInst);
Split Alpha ISA description into multiple files (thanks to Gabe's include feature!). arch/alpha/isa/main.isa: Split out into multiple .isa files. --HG-- extra : convert_revision : 30d8edf74ea194d4a208febf1e66edc72a7dbd5d
2006-02-10 05:02:38 +01:00
}};
def format CondBranch(code) {{
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
code = '''
bool cond;
%(code)s;
if (cond)
Alpha: Take advantage of new PCState syntax.
2010-12-08 19:55:33 +01:00
NPC = NPC + disp;
else
NPC = NPC;
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
''' % { "code" : code }
Convert Alpha (and finish converting MIPS) to new InstObjParam interface. src/arch/alpha/isa/branch.isa: src/arch/alpha/isa/fp.isa: src/arch/alpha/isa/int.isa: src/arch/alpha/isa/main.isa: src/arch/alpha/isa/mem.isa: src/arch/alpha/isa/pal.isa: src/arch/mips/isa/formats/mem.isa: src/arch/mips/isa/formats/util.isa: Get rid of CodeBlock calls to adapt to new InstObjParam interface. src/arch/isa_parser.py: Check template code for operands (in addition to snippets). src/cpu/o3/alpha/dyn_inst.hh: Add (read|write)MiscRegOperand calls to Alpha DynInst. --HG-- extra : convert_revision : 332caf1bee19b014cb62c1ed9e793e793334c8ee
2006-12-18 04:27:50 +01:00
iop = InstObjParams(name, Name, 'Branch', code,
Split Alpha ISA description into multiple files (thanks to Gabe's include feature!). arch/alpha/isa/main.isa: Split out into multiple .isa files. --HG-- extra : convert_revision : 30d8edf74ea194d4a208febf1e66edc72a7dbd5d
2006-02-10 05:02:38 +01:00
('IsDirectControl', 'IsCondControl'))
header_output = BasicDeclare.subst(iop)
decoder_output = BasicConstructor.subst(iop)
decode_block = BasicDecode.subst(iop)
exec_output = BasicExecute.subst(iop)
}};
let {{
def UncondCtrlBase(name, Name, base_class, npc_expr, flags):
# Declare basic control transfer w/o link (i.e. link reg is R31)
Alpha: Take advantage of new PCState syntax.
2010-12-08 19:55:33 +01:00
nolink_code = 'NPC = %s;\n' % npc_expr
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
nolink_iop = InstObjParams(name, Name, base_class,
Alpha: Take advantage of new PCState syntax.
2010-12-08 19:55:33 +01:00
nolink_code, flags)
Split Alpha ISA description into multiple files (thanks to Gabe's include feature!). arch/alpha/isa/main.isa: Split out into multiple .isa files. --HG-- extra : convert_revision : 30d8edf74ea194d4a208febf1e66edc72a7dbd5d
2006-02-10 05:02:38 +01:00
header_output = BasicDeclare.subst(nolink_iop)
decoder_output = BasicConstructor.subst(nolink_iop)
exec_output = BasicExecute.subst(nolink_iop)
# Generate declaration of '*AndLink' version, append to decls
Alpha: Take advantage of new PCState syntax.
2010-12-08 19:55:33 +01:00
link_code = 'Ra = NPC & ~3;\n' + nolink_code
Split Alpha ISA description into multiple files (thanks to Gabe's include feature!). arch/alpha/isa/main.isa: Split out into multiple .isa files. --HG-- extra : convert_revision : 30d8edf74ea194d4a208febf1e66edc72a7dbd5d
2006-02-10 05:02:38 +01:00
link_iop = InstObjParams(name, Name + 'AndLink', base_class,
Alpha: Take advantage of new PCState syntax.
2010-12-08 19:55:33 +01:00
link_code, flags)
Split Alpha ISA description into multiple files (thanks to Gabe's include feature!). arch/alpha/isa/main.isa: Split out into multiple .isa files. --HG-- extra : convert_revision : 30d8edf74ea194d4a208febf1e66edc72a7dbd5d
2006-02-10 05:02:38 +01:00
header_output += BasicDeclare.subst(link_iop)
decoder_output += BasicConstructor.subst(link_iop)
exec_output += BasicExecute.subst(link_iop)
# need to use link_iop for the decode template since it is expecting
# the shorter version of class_name (w/o "AndLink")
return (header_output, decoder_output,
JumpOrBranchDecode.subst(nolink_iop), exec_output)
}};
def format UncondBranch(*flags) {{
flags += ('IsUncondControl', 'IsDirectControl')
(header_output, decoder_output, decode_block, exec_output) = \
Alpha: Take advantage of new PCState syntax.
2010-12-08 19:55:33 +01:00
UncondCtrlBase(name, Name, 'Branch', 'NPC + disp', flags)
Split Alpha ISA description into multiple files (thanks to Gabe's include feature!). arch/alpha/isa/main.isa: Split out into multiple .isa files. --HG-- extra : convert_revision : 30d8edf74ea194d4a208febf1e66edc72a7dbd5d
2006-02-10 05:02:38 +01:00
}};
def format Jump(*flags) {{
flags += ('IsUncondControl', 'IsIndirectControl')
(header_output, decoder_output, decode_block, exec_output) = \
Alpha: Take advantage of new PCState syntax.
2010-12-08 19:55:33 +01:00
UncondCtrlBase(name, Name, 'Jump', '(Rb & ~3) | (NPC & 1)', flags)
Split Alpha ISA description into multiple files (thanks to Gabe's include feature!). arch/alpha/isa/main.isa: Split out into multiple .isa files. --HG-- extra : convert_revision : 30d8edf74ea194d4a208febf1e66edc72a7dbd5d
2006-02-10 05:02:38 +01:00
}};
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