Make ICP uses PSI to check for hotness.
Summary: Currently, ICP checks the count against a fixed value to see if it is hot enough to be promoted. This does not work for SamplePGO because sampled count may be much smaller. This patch uses PSI to check if the count is hot enough to be promoted.
Reviewers: davidxl, tejohnson, eraman
Reviewed By: davidxl
Subscribers: sanjoy, llvm-commits, mehdi_amini
Differential Revision: https://reviews.llvm.org/D36341
llvm-svn: 310416
diff --git a/llvm/lib/Transforms/Instrumentation/IndirectCallPromotion.cpp b/llvm/lib/Transforms/Instrumentation/IndirectCallPromotion.cpp
index abce36d..47e21bd 100644
--- a/llvm/lib/Transforms/Instrumentation/IndirectCallPromotion.cpp
+++ b/llvm/lib/Transforms/Instrumentation/IndirectCallPromotion.cpp
@@ -22,6 +22,7 @@
#include "llvm/Analysis/IndirectCallPromotionAnalysis.h"
#include "llvm/Analysis/IndirectCallSiteVisitor.h"
#include "llvm/Analysis/OptimizationDiagnosticInfo.h"
+#include "llvm/Analysis/ProfileSummaryInfo.h"
#include "llvm/IR/BasicBlock.h"
#include "llvm/IR/CallSite.h"
#include "llvm/IR/DerivedTypes.h"
@@ -121,6 +122,10 @@
*PassRegistry::getPassRegistry());
}
+ void getAnalysisUsage(AnalysisUsage &AU) const override {
+ AU.addRequired<ProfileSummaryInfoWrapperPass>();
+ }
+
StringRef getPassName() const override { return "PGOIndirectCallPromotion"; }
private:
@@ -194,7 +199,7 @@
bool SamplePGO, OptimizationRemarkEmitter &ORE)
: F(Func), M(Modu), Symtab(Symtab), SamplePGO(SamplePGO), ORE(ORE) {}
- bool processFunction();
+ bool processFunction(ProfileSummaryInfo *PSI);
};
} // end anonymous namespace
@@ -613,7 +618,7 @@
// Traverse all the indirect-call callsite and get the value profile
// annotation to perform indirect-call promotion.
-bool ICallPromotionFunc::processFunction() {
+bool ICallPromotionFunc::processFunction(ProfileSummaryInfo *PSI) {
bool Changed = false;
ICallPromotionAnalysis ICallAnalysis;
for (auto &I : findIndirectCallSites(F)) {
@@ -621,7 +626,8 @@
uint64_t TotalCount;
auto ICallProfDataRef = ICallAnalysis.getPromotionCandidatesForInstruction(
I, NumVals, TotalCount, NumCandidates);
- if (!NumCandidates)
+ if (!NumCandidates ||
+ (PSI && PSI->hasProfileSummary() && !PSI->isHotCount(TotalCount)))
continue;
auto PromotionCandidates = getPromotionCandidatesForCallSite(
I, ICallProfDataRef, TotalCount, NumCandidates);
@@ -643,7 +649,8 @@
}
// A wrapper function that does the actual work.
-static bool promoteIndirectCalls(Module &M, bool InLTO, bool SamplePGO,
+static bool promoteIndirectCalls(Module &M, ProfileSummaryInfo *PSI,
+ bool InLTO, bool SamplePGO,
ModuleAnalysisManager *AM = nullptr) {
if (DisableICP)
return false;
@@ -673,7 +680,7 @@
}
ICallPromotionFunc ICallPromotion(F, &M, &Symtab, SamplePGO, *ORE);
- bool FuncChanged = ICallPromotion.processFunction();
+ bool FuncChanged = ICallPromotion.processFunction(PSI);
if (ICPDUMPAFTER && FuncChanged) {
DEBUG(dbgs() << "\n== IR Dump After =="; F.print(dbgs()));
DEBUG(dbgs() << "\n");
@@ -688,15 +695,20 @@
}
bool PGOIndirectCallPromotionLegacyPass::runOnModule(Module &M) {
+ ProfileSummaryInfo *PSI =
+ getAnalysis<ProfileSummaryInfoWrapperPass>().getPSI();
+
// Command-line option has the priority for InLTO.
- return promoteIndirectCalls(M, InLTO | ICPLTOMode,
+ return promoteIndirectCalls(M, PSI, InLTO | ICPLTOMode,
SamplePGO | ICPSamplePGOMode);
}
PreservedAnalyses PGOIndirectCallPromotion::run(Module &M,
ModuleAnalysisManager &AM) {
- if (!promoteIndirectCalls(M, InLTO | ICPLTOMode, SamplePGO | ICPSamplePGOMode,
- &AM))
+ ProfileSummaryInfo *PSI = &AM.getResult<ProfileSummaryAnalysis>(M);
+
+ if (!promoteIndirectCalls(M, PSI, InLTO | ICPLTOMode,
+ SamplePGO | ICPSamplePGOMode, &AM))
return PreservedAnalyses::all();
return PreservedAnalyses::none();