[PGO] Add PGO support at -O0 in the experimental new pass manager
Add PGO support at -O0 in the experimental new pass manager to sync the
behavior of the legacy pass manager.
Also change the test of gcc-flag-compatibility.c for more complete test:
(1) change the match string to "profc" and "profd" to ensure the
instrumentation is happening.
(2) add IR format proftext so that PGO use compilation is tested.
Differential Revision: https://reviews.llvm.org/D64029
llvm-svn: 367628
diff --git a/llvm/lib/Passes/PassBuilder.cpp b/llvm/lib/Passes/PassBuilder.cpp
index eef94bf..6cb6afa 100644
--- a/llvm/lib/Passes/PassBuilder.cpp
+++ b/llvm/lib/Passes/PassBuilder.cpp
@@ -541,6 +541,7 @@
bool RunProfileGen, bool IsCS,
std::string ProfileFile,
std::string ProfileRemappingFile) {
+ assert(Level != O0 && "Not expecting O0 here!");
// Generally running simplification passes and the inliner with an high
// threshold results in smaller executables, but there may be cases where
// the size grows, so let's be conservative here and skip this simplification
@@ -571,34 +572,62 @@
CGPipeline.addPass(createCGSCCToFunctionPassAdaptor(std::move(FPM)));
MPM.addPass(createModuleToPostOrderCGSCCPassAdaptor(std::move(CGPipeline)));
+
+ // Delete anything that is now dead to make sure that we don't instrument
+ // dead code. Instrumentation can end up keeping dead code around and
+ // dramatically increase code size.
+ MPM.addPass(GlobalDCEPass());
}
- // Delete anything that is now dead to make sure that we don't instrument
- // dead code. Instrumentation can end up keeping dead code around and
- // dramatically increase code size.
- MPM.addPass(GlobalDCEPass());
-
- if (RunProfileGen) {
- MPM.addPass(PGOInstrumentationGen(IsCS));
-
- FunctionPassManager FPM;
- FPM.addPass(
- createFunctionToLoopPassAdaptor(LoopRotatePass(), DebugLogging));
- MPM.addPass(createModuleToFunctionPassAdaptor(std::move(FPM)));
-
- // Add the profile lowering pass.
- InstrProfOptions Options;
- if (!ProfileFile.empty())
- Options.InstrProfileOutput = ProfileFile;
- Options.DoCounterPromotion = true;
- Options.UseBFIInPromotion = IsCS;
- MPM.addPass(InstrProfiling(Options, IsCS));
- } else if (!ProfileFile.empty()) {
+ if (!RunProfileGen) {
+ assert(!ProfileFile.empty() && "Profile use expecting a profile file!");
MPM.addPass(PGOInstrumentationUse(ProfileFile, ProfileRemappingFile, IsCS));
// Cache ProfileSummaryAnalysis once to avoid the potential need to insert
// RequireAnalysisPass for PSI before subsequent non-module passes.
MPM.addPass(RequireAnalysisPass<ProfileSummaryAnalysis, Module>());
+ return;
}
+
+ // Perform PGO instrumentation.
+ MPM.addPass(PGOInstrumentationGen(IsCS));
+
+ FunctionPassManager FPM;
+ FPM.addPass(createFunctionToLoopPassAdaptor(LoopRotatePass(), DebugLogging));
+ MPM.addPass(createModuleToFunctionPassAdaptor(std::move(FPM)));
+
+ // Add the profile lowering pass.
+ InstrProfOptions Options;
+ if (!ProfileFile.empty())
+ Options.InstrProfileOutput = ProfileFile;
+ // Do counter promotion at Level greater than O0.
+ Options.DoCounterPromotion = true;
+ Options.UseBFIInPromotion = IsCS;
+ MPM.addPass(InstrProfiling(Options, IsCS));
+}
+
+void PassBuilder::addPGOInstrPassesForO0(ModulePassManager &MPM,
+ bool DebugLogging, bool RunProfileGen,
+ bool IsCS, std::string ProfileFile,
+ std::string ProfileRemappingFile) {
+ if (!RunProfileGen) {
+ assert(!ProfileFile.empty() && "Profile use expecting a profile file!");
+ MPM.addPass(PGOInstrumentationUse(ProfileFile, ProfileRemappingFile, IsCS));
+ // Cache ProfileSummaryAnalysis once to avoid the potential need to insert
+ // RequireAnalysisPass for PSI before subsequent non-module passes.
+ MPM.addPass(RequireAnalysisPass<ProfileSummaryAnalysis, Module>());
+ return;
+ }
+
+ // Perform PGO instrumentation.
+ MPM.addPass(PGOInstrumentationGen(IsCS));
+ // Add the profile lowering pass.
+ InstrProfOptions Options;
+ if (!ProfileFile.empty())
+ Options.InstrProfileOutput = ProfileFile;
+ // Do not do counter promotion at O0.
+ Options.DoCounterPromotion = false;
+ Options.UseBFIInPromotion = IsCS;
+ MPM.addPass(InstrProfiling(Options, IsCS));
}
static InlineParams
@@ -1801,9 +1830,19 @@
.Case("O3", O3)
.Case("Os", Os)
.Case("Oz", Oz);
- if (L == O0)
- // At O0 we do nothing at all!
+ if (L == O0) {
+ // Add instrumentation PGO passes -- at O0 we can still do PGO.
+ if (PGOOpt && Matches[1] != "thinlto" &&
+ (PGOOpt->Action == PGOOptions::IRInstr ||
+ PGOOpt->Action == PGOOptions::IRUse))
+ addPGOInstrPassesForO0(
+ MPM, DebugLogging,
+ /* RunProfileGen */ (PGOOpt->Action == PGOOptions::IRInstr),
+ /* IsCS */ false, PGOOpt->ProfileFile,
+ PGOOpt->ProfileRemappingFile);
+ // Do nothing else at all!
return Error::success();
+ }
if (Matches[1] == "default") {
MPM.addPass(buildPerModuleDefaultPipeline(L, DebugLogging));