Suppose the saturating counters of a branch predictor contain n bits. When the
counter is between 0 and (2^(n-1) - 1), boundaries included, the branch is
predicted as not taken. When the counter is between 2^(n-1) and (2^n - 1),
boundaries included, the branch is predicted as taken.
when insts execute, they mark the time they finish to be used for subsequent isnts
they may need forwarding of data. However, the regdepmap was using the wrong
value to index into the destination operands of the instruction to be forwarded.
Thus, in some cases, we are checking to see if the 3rd destination register
for an instruction is executed at a certain time, when there is only 1 dest. register
valid. Thus, we get a bad, uninitialized time value that will stall forwarding
causing performance loss but still the correct execution.
In addition to obvious changes, this required a slight change to the slicc
grammar to allow types with :: in them. Otherwise slicc barfs on std::string
which we need for the headers that slicc generates.
make sure to only read 1 src reg. for write-hint and any other similar
'store' instruction. Reading the source reg when its not necessary
can cause the simulator to read from uninitialized values
These recordEvent() calls could cause crashes since they
access the req pointer after it's potentially been
deleted during a failed translation call. (Similar
problem to the traceData bug fixed in the previous cset.)
Moving them above the translation call (as was done
recentlyi in cset 8b2b8e5e7d35) avoids the crash
but doesn't work, since at that point we don't know if
the access is uncached or not.
It's not clear why these calls are there, and no one
seems to use them, so we'll just delete them. If they
are needed, they should be moved to somewhere that's
guaranteed to be after the translation completes but
before the request is possibly deleted, e.g., in
finishTranslation().
Accessing traceData (to call setAddress() and/or setData())
after initiating a timing translation was causing crashes,
since a failed translation could delete the traceData
object before returning.
It turns out that there was never a need to access traceData
after initiating the translation, as the traced data was
always available earlier; this ordering was merely
historical. Furthermore, traceData->setAddress() and
traceData->setData() were being called both from the CPU
model and the ISA definition, often redundantly.
This patch standardizes all setAddress and setData calls
for memory instructions to be in the CPU models and not
in the ISA definition. It also moves those calls above
the translation calls to eliminate the crashes.
When implementing timing address translations instead of atomic, I
forgot to preserve the faults that are returned from the read and
write calls. This patch reinstates them.
When each load or store is sent to the LSQ, we check whether it will cross a
cache line boundary and, if so, split it in two. This creates two TLB
translations and two memory requests. Care has to be taken if the first
packet of a split load is sent but the second blocks the cache. Similarly,
for a store, if the first packet cannot be sent, we must store the second
one somewhere to retry later.
This modifies the LSQSenderState class to record both packets in a split
load or store.
Finally, a new const variable, HasUnalignedMemAcc, is added to each ISA
to indicate whether unaligned memory accesses are allowed. This is used
throughout the changed code so that compiler can optimise away code dealing
with split requests for ISAs that don't need them.
This initiates a timing translation and passes the read or write on to the
processor before waiting for it to finish. Once the translation is finished,
the instruction's state is updated via the 'finish' function. A new
DataTranslation class is created to handle this.
The idea is taken from the implementation of timing translations in
TimingSimpleCPU by Gabe Black. This patch also separates out the timing
translations from this CPU and uses the new DataTranslation class.
- on certain retry requests you can get an assertion failure
- fix by allowing the request to literally "Retry" itself
if it wasnt successful before, and then block any requests
through cache port while waiting for the cache to be
made available for access
when threads are switching in/out the CPU, we need to keep
track of special cases like branches. Add appropriate
variables in ThreadState t track this and then use
these variables when updating pc after context switch
this will be used for when a thread comes back from a cache miss, it needs to update the PCs
because the inst might of been a branch or delayslot in which the next PC isnt always
a straight addition
allow a thread to wakeup and be activated after
it has been in suspended state and another
thread is switched out. Need to give
pipeline stages a "activateThread" function
so that can get to their suspended instruction
when the time is right.
give resources their own specific
activity to do for a "suspend" event
instead of defaulting to deactivating the thread for a
suspend thread event. This really matters
for the fetch sequence unit which wants to remove the
thread from fetching while other units want to
ignore a thread suspension. If you deactivate a thread
in a resource then you may lose some of the allotted
bandwidth that the thread is taking up...
update/add in the use of isThreadReady & isThreadSuspended
functions.Check in activateThread what list a thread is
on so it can be managed accordingly.
-Support ability to activate next ready thread after a cache miss
through the activateNextReadyContext/Thread() functions
-To support this a "readyList" of thread ids is added
-After a cache miss, thread will suspend and then call
activitynextreadythread
allow for events to schedule themselves later if desired. this is important
because of cases like where you need to activate a thread only after the previous
thread has been deactivated. The ordering there has to be enforced
add code to recognize memory stalls in resources and the pipeline as well
as squash a thread if there is a stall and we are in the switch on cache miss
model
add buffer for instructions to switch out to in a pipeline stage
can't squash the instruction and remove the pipeline so we kind of need
to 'suspend' an instruction at the stage while the memory stall resolves
for the switch on cache miss model
- loads were happening on same cycle as the address was generated which is slightly
unrealistic. Instead, force address generation to be on separate cycle from load
initiation
- also, mark the stages in a more traditional way (F-D-X-M-W)
This adds support for the 32-bit, big endian Power ISA. This supports both
integer and floating point instructions based on the Power ISA Book I v2.06.
When enabled, faulting instructions appear in the trace twice
(once when they fault and again when they're re-executed).
This flag is set by the Exec compound flag for backwards compatibility.
Get rid of misc.py and just stick misc things in __init__.py
Move utility functions out of SCons files and into m5.util
Move utility type stuff from m5/__init__.py to m5/util/__init__.py
Remove buildEnv from m5 and allow access only from m5.defines
Rename AddToPath to addToPath while we're moving it to m5.util
Rename read_command to readCommand while we're moving it
Rename compare_versions to compareVersions while we're moving it.
--HG--
rename : src/python/m5/convert.py => src/python/m5/util/convert.py
rename : src/python/m5/smartdict.py => src/python/m5/util/smartdict.py
TLBUnit no longer used and we also get rid of memAccSize and memAccFlags functions added to ISA and StaticInst
since TLB is not a separate resource to acquire. Instead, TLB access is done before any read/write to memory
and the result is checked before it's sent out to memory.
* * *
inorder was incorrectly storing FP values and confusing the integer/fp storage view of floating point operations. A big issue was knowing trying to infer when were doing single or double precision access
because this lets you know the size of value to store (32-64 bits). This isnt exactly straightforward since alpha uses all 64-bit regs while mips/sparc uses a dual-reg view. by getting this value from
the actual floating point register file, the model can figure out what it needs to store
Remove subinstructions eaComp/memAcc since unused in CPU Models. Instead, create eaComp that is visible from StaticInst object. Gives InOrder model capability of generating address without actually initiating access
* * *
Changes so that InOrder can work for a non-delay-slot ISA like Alpha. Typically, changes have to do with handling misspeculated branches at different points in pipeline
Edit AlphaISA to support the inorder model. Mostly alternate constructor functions and also a few skeleton multithreaded support functions
* * *
Remove namespace from header file. Causes compiler issues that are hard to find
* * *
Separate the TLB from the CPU and allow it to live in the TLBUnit resource. Give CPU accessor functions for access and also bind at construction time
* * *
Expose memory access size and flags through instruction object
(temporarily memAccSize and memFlags to get TLB stuff working.)
this was double scheduling itself (once in constructor and once in cpu code). also add support for stopping / starting
progress events through repeatEvent flag and also changing the interval of the progress event as well
For some reason o3 FS init() only called initCPU if the thread state
was Suspended, which was no longer the case. There's no apparent
reason to check, so I whacked the test completely rather than
changing the check to Halted.
The inorder init() was also updated to be symmetric, though the
previous code was just a fancy no-op.
This situation can arise now on the first fetch cycle after
the last active thread is halted. It seems easy enough to
deal with when it happens rather than trying to avoid it.
This provides a common initial status for all threads independent
of CPU model (unlike the prior situation where CPUs initialized
threads to inconsistent states).
This mostly matters for SE mode; in FS mode, ISA-specific startupCPU()
methods generally handle boot-time initialization of thread contexts
(since the right thing to do is ISA-dependent).
Basically merge it in with Halted.
Also had to get rid of a few other functions that
called ThreadContext::deallocate(), including:
- InOrderCPU's setThreadRescheduleCondition.
- ThreadContext::exit(). This function was there to avoid terminating
simulation when one thread out of a multi-thread workload exits, but we
need to find a better (non-cpu-centric) way.
Apparently we broke it with the cache rewrite and never noticed.
Thanks to Bao Yungang <baoyungang@gmail.com> for a significant part
of these changes (and for inspiring me to work on the rest).
Some other overdue cleanup on the prefetch code too.
This model currently only works in MIPS_SE mode, so it will take some effort
to clean it up and make it generally useful. Hopefully people are willing to
help make that happen!
Make interrupts use the new wakeup method, and pull all of the interrupt
stuff into the cpu base class so that only the wakeup code needs to be updated.
I tried to make wakeup, wakeCPU, and the various other mechanisms for waking
and sleeping a little more sane, but I couldn't understand why the statistics
were changing the way they were. Maybe we'll try again some day.
the primary identifier for a hardware context should be contextId(). The
concept of threads within a CPU remains, in the form of threadId() because
sometimes you need to know which context within a cpu to manipulate.
SE. Process still keeps track of the tc's it owns, but registration occurs
with the System, this eases the way for system-wide context Ids based on
registration.
across the subclasses. generally make it so that member data is _cpuId and
accessor functions are cpuId(). The ID val comes from the python (default -1 if
none provided), and if it is -1, the index of cpuList will be given. this has
passed util/regress quick and se.py -n4 and fs.py -n4 as well as standard
switch.
The constructor no-longer schedules an event at construction and the implict conversion between int and bool was allowing the old code to compile without warning.
Signed-off By: Ali Saidi
the instruction after the hwrei to be fetched before the ITB/DTB_CM register is updated in a call pal
call sys and thus the translation fails because the user is attempting to access a super page address.
Minimally, it seems as though some sort of fetch stall or refetch after a hwrei is required. I think
this works currently because the hwrei uses the exec context interface, and the o3 stalls when that occurs.
Additionally, these changes don't update the LOCK register and probably break ll/sc. Both o3 changes were
removed since a great deal of manual patching would be required to only remove the hwrei change.
Make them easier to express by only having the cxx_type parameter which
has the full namespace name, and drop the cxx_namespace thing.
Add support for multiple levels of namespace.
Even though we're not incorrect about operator precedence, let's add
some parens in some particularly confusing places to placate GCC 4.3
so that we don't have to turn the warning off. Agreed that this is a
bit of a pain for those users who get the order of operations correct,
but it is likely to prevent bugs in certain cases.
Fix the logic in the LSQ that determines if there are any stores to
write back. In the commit stage, check for thread specific writebacks
instead of just any writeback.
python type of a latency. In addition, the multiple definitions of profile in the different cpu models caused
problems for intialization of the interval value. If a child class's profile value was defined, the parent
BaseCPU::ProfileEvent interval field would be initialized with a garbage value. The fix was to remove the
multiple redifitions of profile in the child CPU classes.
A whole bunch of stuff has been converted to use the new params stuff, but
the CPU wasn't one of them. While we're at it, make some things a bit
more stylish. Most of the work was done by Gabe, I just cleaned stuff up
a bit more at the end.
When invoking several copies of m5 on the same machine at the same
time, there can be a race for TCP ports for the terminal connections
or remote gdb. Expose a function to disable those ports, and have the
regression scripts disable them. There are some SimObjects that have
no other function than to be used with ports (NativeTrace and
EtherTap), so they will panic if the ports are disabled.
The notIdleFraction statistic isn't updated when the statistics reset, probably because the cpu Status information
was pulled into the atomic and timing cpus. This changeset pulls Status back into the BaseSimpleCPU object. Anyone
care to comment on the odd naming of the Status instance? It shouldn't just be status because that is confusing
with Port::Status, but _status seems a bit strage too.
This should help if somebody gets to the bug
fix before me (or someone else)...
--HG--
extra : convert_revision : 0ae64c58ef4f7b02996f31e9e9e6bfad344719e2
from the right point (#32 usually) instead of restarting at 0 and double-freeing.
Commented out assert line in free_list.hh that will check for when double-free condition
goes bad.
--HG--
extra : convert_revision : 08d5f9b6a874736e487d101e85c22aaa67bf59ae
where we defer a response to a read from a far-away cache A, then later
defer a ReadExcl from a cache B on the same bus as us. We'll assert
MemInhibit in both cases, but in the latter case MemInhibit will keep
the invalidation from reaching cache A. This special response tells
cache A that it gets the block to satisfy its read, but must immediately
invalidate it.
--HG--
extra : convert_revision : f85c8b47bb30232da37ac861b50a6539dc81161b
Also some bug fixes in MIPS ISA uncovered by g++ warnings
(Python string compares don't work in C++!).
--HG--
extra : convert_revision : b347cc0108f23890e9b73b3ee96059f0cea96cf6
SimObjects not yet updated:
- Process and subclasses
- BaseCPU and subclasses
The SimObject(const std::string &name) constructor was removed. Subclasses
that still rely on that behavior must call the parent initializer as
: SimObject(makeParams(name))
--HG--
extra : convert_revision : d6faddde76e7c3361ebdbd0a7b372a40941c12ed
It should be cleared prior to the call to recvRetry.
Add extra DPRINTF statement for clearer debugging output.
--HG--
extra : convert_revision : e2332754743f42d60e159ac89f6fb0fd8b7f57f8
Ignore different values or rcx and r11 after a syscall until either the local or remote value changes. Also change the codes organization somewhat.
--HG--
extra : convert_revision : 2c1f69d4e55b443e68bfc7b43e8387b02cf0b6b5
People should never put pointers in DPRINTFs; it messes up
tracediffs. Plus these used the FullCPU trace flag, which
is not right.
--HG--
extra : convert_revision : 82ed56757da0ad947c165ba205b5f752c85c6667
The correct order is unintuitively rax, rcx, rdx, rbx, etc, not rax, rbx, rcx, rdx.
--HG--
extra : convert_revision : 3abe6a723a6e30becfe34f8da707ea2ff5d4df77
Code was assuming that all argument registers followed in order from ArgumentReg0. There is now an ArgumentReg array which is indexed to find the right index. There is a constant, NumArgumentRegs, which can be used to protect against using an invalid ArgumentReg.
--HG--
extra : convert_revision : f448a3ca4d6adc3fc3323562870f70eec05a8a1f
creation and initialization now happens in python. Parameter objects
are generated and initialized by python. The .ini file is now solely for
debugging purposes and is not used in construction of the objects in any
way.
--HG--
extra : convert_revision : 7e722873e417cb3d696f2e34c35ff488b7bff4ed
src/cpu/simple/timing.cc:
Fix another SC problem.
src/mem/cache/cache_impl.hh:
Forgot to call makeTimingResponse() on uncached timing responses.
--HG--
extra : convert_revision : 5a5a58ca2053e4e8de2133205bfd37de15eb4209
into vm1.(none):/home/stever/bk/newmem-cache2
src/base/traceflags.py:
Hand merge.
--HG--
extra : convert_revision : 9e7539eeab4220ed7a7237457a8f336f79216924
src/cpu/memtest/memtest.cc:
Need to set packet source field so that response from cache
doesn't run into assertion failure when copying source to dest.
src/mem/packet.hh:
Copy source field when copying packets.
Assert that source is valid before copying it to dest
when turning packets around.
--HG--
extra : convert_revision : 09e3cfda424aa89fe170e21e955b295746832bf8
into ahchoo.blinky.homelinux.org:/home/gblack/m5/newmem-o3-micro
src/cpu/o3/fetch_impl.hh:
hand merge
--HG--
extra : convert_revision : 3f71f3ac2035eec8b6f7bceb6906edb4dd09c045
supposed to and make sure parameters have the right type.
Also make sure that any object that should be an intermediate
type has the right options set.
--HG--
extra : convert_revision : d56910628d9a067699827adbc0a26ab629d11e93
into doughnut.hpl.hp.com:/home/gblack/newmem-o3-micro
src/cpu/base_dyn_inst_impl.hh:
src/cpu/o3/fetch_impl.hh:
Hand merge
--HG--
extra : convert_revision : 0c0692033ac30133672d8dfe1f1a27e9d9e95a3d
time it was responded to is curTick. Doesn't change the results, but it does make implementation of nextCycle() more difficult
--HG--
extra : convert_revision : 67ed6261a5451d17d96d5df45992590acc353afc
into vm1.(none):/home/stever/bk/newmem-cache2
configs/example/memtest.py:
Hand merge redundant changes.
--HG--
extra : convert_revision : a2e36be254bf052024f37bcb23b5209f367d37e1
timing mode still broken.
configs/example/memtest.py:
Revamp options.
src/cpu/memtest/memtest.cc:
No need for memory initialization.
No need to make atomic response... memory system should do that now.
src/cpu/memtest/memtest.hh:
MemTest really doesn't want to snoop.
src/mem/bridge.cc:
checkFunctional() cleanup.
src/mem/bus.cc:
src/mem/bus.hh:
src/mem/cache/base_cache.cc:
src/mem/cache/base_cache.hh:
src/mem/cache/cache.cc:
src/mem/cache/cache.hh:
src/mem/cache/cache_blk.hh:
src/mem/cache/cache_builder.cc:
src/mem/cache/cache_impl.hh:
src/mem/cache/coherence/coherence_protocol.cc:
src/mem/cache/coherence/coherence_protocol.hh:
src/mem/cache/coherence/simple_coherence.hh:
src/mem/cache/miss/SConscript:
src/mem/cache/miss/mshr.cc:
src/mem/cache/miss/mshr.hh:
src/mem/cache/miss/mshr_queue.cc:
src/mem/cache/miss/mshr_queue.hh:
src/mem/cache/prefetch/base_prefetcher.cc:
src/mem/cache/tags/fa_lru.cc:
src/mem/cache/tags/fa_lru.hh:
src/mem/cache/tags/iic.cc:
src/mem/cache/tags/iic.hh:
src/mem/cache/tags/lru.cc:
src/mem/cache/tags/lru.hh:
src/mem/cache/tags/split.cc:
src/mem/cache/tags/split.hh:
src/mem/cache/tags/split_lifo.cc:
src/mem/cache/tags/split_lifo.hh:
src/mem/cache/tags/split_lru.cc:
src/mem/cache/tags/split_lru.hh:
src/mem/packet.cc:
src/mem/packet.hh:
src/mem/physical.cc:
src/mem/physical.hh:
src/mem/tport.cc:
More major reorg. Seems to work for atomic mode now,
timing mode still broken.
--HG--
extra : convert_revision : 7e70dfc4a752393b911880ff028271433855ae87
No need to initialize memory contents; should come up as 0.
src/cpu/memtest/memtest.cc:
No need to initialize memory contents; should come up as 0.
--HG--
extra : convert_revision : 1713676956f3d33b4686fee2650bd17027bcc495
Make code compatible with new decode method.
src/arch/alpha/remote_gdb.cc:
src/cpu/base_dyn_inst_impl.hh:
src/cpu/exetrace.cc:
src/cpu/simple/base.cc:
Make code compatible with new decode method.
src/cpu/static_inst.cc:
src/cpu/static_inst.hh:
Modified instruction decode method.
--HG--
extra : convert_revision : a9a6d3a16fff59bc95d0606ea344bd57e71b8d0a
src/arch/x86/predecoder.cc:
Seperate the pc-pc and the pc of the incoming bytes, and get rid of the "moreBytes" which just takes a MachInst. Also make the "opSize" field describe the number of bytes and not the log of the number of bytes.
--HG--
extra : convert_revision : 3a5ec7053ec69c5cba738a475d8b7fd9e6e6ccc0
src/arch/x86/isa/macroop.isa:
Make microOp vs microop and macroOp vs macroop capitilization consistent. Also fill out the emulation environment handling a little more, and use an object to pass around output code.
src/arch/x86/isa/microops/base.isa:
Make microOp vs microop and macroOp vs macroop capitilization consistent. Also adjust python to C++ bool translation.
--HG--
extra : convert_revision : 6f4bacfa334c42732c845f9a7f211cbefc73f96f
real thing. Also rename the null case to something that can
be a C++ symbol.
--HG--
extra : convert_revision : e3bfc4065b59c21f613e486d234711c48d7c9070
into ahchoo.blinky.homelinux.org:/home/gblack/m5/newmem-x86
src/cpu/simple/base.cc:
Hand merge
--HG--
extra : convert_revision : a2902ef9d917d22ffb9c7dfa2fd444694a65240d
Initialize a temporary variable for thread->readPC() at setupFetchRequest() to reduce function calls.
exec tracing isn't needed for m5.fast binaries
Moved MISCREG_GL, MISCREG_CWP, and MISCREG_TLB_DATA out of switch statement and use if blocks instead.
src/arch/sparc/miscregfile.cc:
Moved MISCREG_GL, MISCREG_CWP, and MISCREG_TLB_DATA out of switch statement and use if blocks instead.
src/cpu/simple/base.cc:
Assign traceData to be NULL at BaseSimpleCPU constructor.
Initialize a temporary variable for thread->readPC() at setupFetchRequest() to reduce function calls.
exec tracing isn't needed for m5.fast binaries
--HG--
extra : convert_revision : 5dc92fff05c9bde994f1e0f1bb40e11c44eb72c6
fix the timing cpu to handle receiving a nacked packet
src/cpu/simple/timing.cc:
make the timing cpu handle receiving a nacked packet
src/mem/bridge.cc:
src/mem/bridge.hh:
the bridge never returns false when recvTiming() is called on its ports now, it always returns true and nacks the packet if there isn't sufficient buffer space
--HG--
extra : convert_revision : 5e12d0cf6ce985a5f72bcb7ce26c83a76c34c50a
src/cpu/simple/base.cc:
Cpu's should start as unallocated, not suspended
src/cpu/simple_thread.cc:
Wait for a thread to be assigned to activate the cpu
src/kern/tru64/tru64.hh:
When looking for a open cpu to assign threads, look for an unallocated one, not a suspended one.
--HG--
extra : convert_revision : 5e3ad2e96b4a715ed38293ceaccff5b9f4ea7985
src/cpu/o3/alpha/cpu_impl.hh:
Pass ISA-specific O3 CPU to FullO3CPU as a constructor parameter instead of using setCPU functions.
--HG--
extra : convert_revision : 74f4b1f5fb6f95a56081f367cce7ff44acb5688a
