From c460ef61d64f3ccb46f60d1b53f271f5b1c05b79 Mon Sep 17 00:00:00 2001 From: wlei Date: Tue, 16 Feb 2021 12:55:06 -0800 Subject: [PATCH] [CSSPGO][llvm-profgen] Change sample count of dangling probe in llvm-profgen Differential Revision: https://reviews.llvm.org/D96811 --- llvm/include/llvm/ProfileData/SampleProf.h | 7 +++++++ llvm/test/tools/llvm-profgen/inline-cs-pseudoprobe.test | 6 +++--- llvm/test/tools/llvm-profgen/noinline-cs-pseudoprobe.test | 6 +++--- llvm/tools/llvm-profgen/ProfileGenerator.cpp | 12 +++++++++++- 4 files changed, 24 insertions(+), 7 deletions(-) diff --git a/llvm/include/llvm/ProfileData/SampleProf.h b/llvm/include/llvm/ProfileData/SampleProf.h index 7c79577..11b160f 100644 --- a/llvm/include/llvm/ProfileData/SampleProf.h +++ b/llvm/include/llvm/ProfileData/SampleProf.h @@ -552,6 +552,13 @@ public: FName, Num, Weight); } + sampleprof_error addBodySamplesForProbe(uint32_t Index, uint64_t Num, + uint64_t Weight = 1) { + SampleRecord S; + S.addSamples(Num, Weight); + return BodySamples[LineLocation(Index, 0)].merge(S, Weight); + } + /// Return the number of samples collected at the given location. /// Each location is specified by \p LineOffset and \p Discriminator. /// If the location is not found in profile, return error. diff --git a/llvm/test/tools/llvm-profgen/inline-cs-pseudoprobe.test b/llvm/test/tools/llvm-profgen/inline-cs-pseudoprobe.test index c7aa1de..cb414c2 100644 --- a/llvm/test/tools/llvm-profgen/inline-cs-pseudoprobe.test +++ b/llvm/test/tools/llvm-profgen/inline-cs-pseudoprobe.test @@ -9,10 +9,10 @@ ; CHECK-NEXT: 6: 15 ; CHECK-NEXT: 8: 14 bar:14 ; CHECK-NEXT: !CFGChecksum: 138950591924 -; CHECK-NEXT:[main:2 @ foo:8 @ bar]:56:14 +; CHECK-NEXT:[main:2 @ foo:8 @ bar]:28:14 ; CHECK-NEXT: 1: 14 -; CHECK-NEXT: 2: 14 -; CHECK-NEXT: 3: 14 +; CHECK-NEXT: 2: 18446744073709551615 +; CHECK-NEXT: 3: 18446744073709551615 ; CHECK-NEXT: 4: 14 ; CHECK-NEXT: !CFGChecksum: 72617220756 diff --git a/llvm/test/tools/llvm-profgen/noinline-cs-pseudoprobe.test b/llvm/test/tools/llvm-profgen/noinline-cs-pseudoprobe.test index a0e5507..64a8b05 100644 --- a/llvm/test/tools/llvm-profgen/noinline-cs-pseudoprobe.test +++ b/llvm/test/tools/llvm-profgen/noinline-cs-pseudoprobe.test @@ -8,10 +8,10 @@ ; CHECK-NEXT: 6: 15 ; CHECK-NEXT: 8: 15 bar:15 ; CHECK-NEXT: !CFGChecksum: 138950591924 -; CHECK-NEXT:[main:2 @ foo:8 @ bar]:60:15 +; CHECK-NEXT:[main:2 @ foo:8 @ bar]:30:15 ; CHECK-NEXT: 1: 15 -; CHECK-NEXT: 2: 15 -; CHECK-NEXT: 3: 15 +; CHECK-NEXT: 2: 18446744073709551615 +; CHECK-NEXT: 3: 18446744073709551615 ; CHECK-NEXT: 4: 15 ; CHECK-NEXT: !CFGChecksum: 72617220756 diff --git a/llvm/tools/llvm-profgen/ProfileGenerator.cpp b/llvm/tools/llvm-profgen/ProfileGenerator.cpp index 4cfadff..d4233a8 100644 --- a/llvm/tools/llvm-profgen/ProfileGenerator.cpp +++ b/llvm/tools/llvm-profgen/ProfileGenerator.cpp @@ -492,7 +492,17 @@ void PseudoProbeCSProfileGenerator::populateBodySamplesWithProbes( FunctionSamples &FunctionProfile = getFunctionProfileForLeafProbe(ContextStrStack, Probe, Binary); - FunctionProfile.addBodySamples(Probe->Index, 0, Count); + // Use InvalidProbeCount(UINT64_MAX) to mark sample count for a dangling + // probe. Dangling probes are the probes associated to an empty block. With + // this place holder, sample count on dangling probe will not be trusted by + // the compiler and it will rely on the counts inference algorithm to get + // the probe a reasonable count. + if (Probe->isDangling()) { + FunctionProfile.addBodySamplesForProbe( + Probe->Index, FunctionSamples::InvalidProbeCount); + continue; + } + FunctionProfile.addBodySamplesForProbe(Probe->Index, Count); FunctionProfile.addTotalSamples(Count); if (Probe->isEntry()) { FunctionProfile.addHeadSamples(Count); -- 2.7.4