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cpu-minor: Ensure the pc in BranchData is always set.

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Change the type passed to updateBranchData in execute to be a reference,
and replace the nullptr being passed in from Execute::evaluate() with
the current thread's pc. We could use any generic PC instead which might
be slightly faster, but there is likely not a significant difference
and this is a lot easier.

Change-Id: I306ca53b33997f76217c61123e5922df612005f9
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/53584
Maintainer: Gabe Black <gabe.black@gmail.com>
Reviewed-by: Bobby Bruce <bbruce@ucdavis.edu>
Tested-by: kokoro <noreply+kokoro@google.com>
This commit is contained in:
Gabe Black
2021-12-03 18:39:05 -08:00
parent fb2f99cb6c
commit 4ed7341abb
4 changed files with 10 additions and 9 deletions
Download Patch File Download Diff File Expand all files Collapse all files

13
src/cpu/minor/execute.cc
View File

@@ -296,14 +296,14 @@ Execute::tryToBranch(MinorDynInstPtr inst, Fault fault, BranchData &branch)
reason = BranchData::NoBranch;
}
updateBranchData(inst->id.threadId, reason, inst, target.get(), branch);
updateBranchData(inst->id.threadId, reason, inst, *target, branch);
}
void
Execute::updateBranchData(
ThreadID tid,
BranchData::Reason reason,
MinorDynInstPtr inst, const PCStateBase *target,
MinorDynInstPtr inst, const PCStateBase &target,
BranchData &branch)
{
if (reason != BranchData::NoBranch) {
@@ -443,7 +443,7 @@ Execute::takeInterrupt(ThreadID thread_id, BranchData &branch)
/* Assume that an interrupt *must* cause a branch. Assert this? */
updateBranchData(thread_id, BranchData::Interrupt,
MinorDynInst::bubble(), &cpu.getContext(thread_id)->pcState(),
MinorDynInst::bubble(), cpu.getContext(thread_id)->pcState(),
branch);
}
@@ -1032,7 +1032,7 @@ Execute::commitInst(MinorDynInstPtr inst, bool early_memory_issue,
cpu.stats.numFetchSuspends++;
updateBranchData(thread_id, BranchData::SuspendThread, inst,
&resume_pc, branch);
resume_pc, branch);
}
}
@@ -1140,7 +1140,7 @@ Execute::commit(ThreadID thread_id, bool only_commit_microops, bool discard,
/* Branch as there was a change in PC */
updateBranchData(thread_id, BranchData::UnpredictedBranch,
MinorDynInst::bubble(), &thread->pcState(), branch);
MinorDynInst::bubble(), thread->pcState(), branch);
} else if (mem_response &&
num_mem_refs_committed < memoryCommitLimit)
{
@@ -1495,7 +1495,8 @@ Execute::evaluate()
* the bag */
if (commit_info.drainState == DrainHaltFetch) {
updateBranchData(commit_tid, BranchData::HaltFetch,
MinorDynInst::bubble(), nullptr, branch);
MinorDynInst::bubble(),
cpu.getContext(commit_tid)->pcState(), branch);
cpu.wakeupOnEvent(Pipeline::ExecuteStageId);
setDrainState(commit_tid, DrainAllInsts);