From 9dc572f568d55568174020218d3b939c1ba8d102 Mon Sep 17 00:00:00 2001 From: Diego Novillo Date: Fri, 16 Oct 2015 18:54:35 +0000 Subject: [PATCH] Sample profiles - Re-arrange binary format to emit head samples only on top functions. The number of samples collected at the head of a function only make sense for top-level functions (i.e., those actually called as opposed to being inlined inside another). Head samples essentially count the time spent inside the function's prologue. This clearly doesn't make sense for inlined functions, so we were always emitting 0 in those. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@250539 91177308-0d34-0410-b5e6-96231b3b80d8 --- include/llvm/ProfileData/SampleProf.h | 2 +- include/llvm/ProfileData/SampleProfReader.h | 8 +++++-- include/llvm/ProfileData/SampleProfWriter.h | 1 + lib/ProfileData/SampleProfReader.cpp | 21 +++++++++--------- lib/ProfileData/SampleProfWriter.cpp | 21 +++++++++++------- .../SampleProfile/Inputs/fnptr.binprof | Bin 105 -> 105 bytes 6 files changed, 32 insertions(+), 21 deletions(-) diff --git a/include/llvm/ProfileData/SampleProf.h b/include/llvm/ProfileData/SampleProf.h index e46407bde2c..96df141e4b2 100644 --- a/include/llvm/ProfileData/SampleProf.h +++ b/include/llvm/ProfileData/SampleProf.h @@ -61,7 +61,7 @@ static inline uint64_t SPMagic() { uint64_t('2') << (64 - 56) | uint64_t(0xff); } -static inline uint64_t SPVersion() { return 101; } +static inline uint64_t SPVersion() { return 102; } /// Represents the relative location of an instruction. /// diff --git a/include/llvm/ProfileData/SampleProfReader.h b/include/llvm/ProfileData/SampleProfReader.h index 02bb85af10f..2f404be50e6 100644 --- a/include/llvm/ProfileData/SampleProfReader.h +++ b/include/llvm/ProfileData/SampleProfReader.h @@ -136,12 +136,16 @@ // A NUL-separated list of SIZE strings. // // FUNCTION BODY (one for each uninlined function body present in the profile) +// HEAD_SAMPLES (uint64_t) [only for top-level functions] +// Total number of samples collected at the head (prologue) of the +// function. +// NOTE: This field should only be present for top-level functions +// (i.e., not inlined into any caller). Inlined function calls +// have no prologue, so they don't need this. // NAME_IDX (uint32_t) // Index into the name table indicating the function name. // SAMPLES (uint64_t) // Total number of samples collected in this function. -// HEAD_SAMPLES (uint64_t) -// Total number of samples collected at the head of the function. // NRECS (uint32_t) // Total number of sampling records this function's profile. // BODY RECORDS diff --git a/include/llvm/ProfileData/SampleProfWriter.h b/include/llvm/ProfileData/SampleProfWriter.h index 48fbe10a6ab..4bd5c71e002 100644 --- a/include/llvm/ProfileData/SampleProfWriter.h +++ b/include/llvm/ProfileData/SampleProfWriter.h @@ -105,6 +105,7 @@ protected: std::error_code writeHeader(const StringMap &ProfileMap) override; std::error_code writeNameIdx(StringRef FName); + std::error_code writeBody(StringRef FName, const FunctionSamples &S); private: void addName(StringRef FName); diff --git a/lib/ProfileData/SampleProfReader.cpp b/lib/ProfileData/SampleProfReader.cpp index 1ea7d2a0c4b..d184969e046 100644 --- a/lib/ProfileData/SampleProfReader.cpp +++ b/lib/ProfileData/SampleProfReader.cpp @@ -21,13 +21,13 @@ //===----------------------------------------------------------------------===// #include "llvm/ProfileData/SampleProfReader.h" +#include "llvm/ADT/DenseMap.h" +#include "llvm/ADT/SmallVector.h" #include "llvm/Support/Debug.h" #include "llvm/Support/ErrorOr.h" #include "llvm/Support/LEB128.h" #include "llvm/Support/LineIterator.h" #include "llvm/Support/MemoryBuffer.h" -#include "llvm/ADT/DenseMap.h" -#include "llvm/ADT/SmallVector.h" using namespace llvm::sampleprof; using namespace llvm; @@ -293,15 +293,10 @@ ErrorOr SampleProfileReaderBinary::readStringFromTable() { std::error_code SampleProfileReaderBinary::readProfile(FunctionSamples &FProfile) { - auto Val = readNumber(); - if (std::error_code EC = Val.getError()) + auto NumSamples = readNumber(); + if (std::error_code EC = NumSamples.getError()) return EC; - FProfile.addTotalSamples(*Val); - - Val = readNumber(); - if (std::error_code EC = Val.getError()) - return EC; - FProfile.addHeadSamples(*Val); + FProfile.addTotalSamples(*NumSamples); // Read the samples in the body. auto NumRecords = readNumber(); @@ -370,6 +365,10 @@ SampleProfileReaderBinary::readProfile(FunctionSamples &FProfile) { std::error_code SampleProfileReaderBinary::read() { while (!at_eof()) { + auto NumHeadSamples = readNumber(); + if (std::error_code EC = NumHeadSamples.getError()) + return EC; + auto FName(readStringFromTable()); if (std::error_code EC = FName.getError()) return EC; @@ -377,6 +376,8 @@ std::error_code SampleProfileReaderBinary::read() { Profiles[*FName] = FunctionSamples(); FunctionSamples &FProfile = Profiles[*FName]; + FProfile.addHeadSamples(*NumHeadSamples); + if (std::error_code EC = readProfile(FProfile)) return EC; } diff --git a/lib/ProfileData/SampleProfWriter.cpp b/lib/ProfileData/SampleProfWriter.cpp index daf3783aba6..a6e3cabd89e 100644 --- a/lib/ProfileData/SampleProfWriter.cpp +++ b/lib/ProfileData/SampleProfWriter.cpp @@ -122,19 +122,15 @@ std::error_code SampleProfileWriterBinary::writeHeader( return sampleprof_error::success; } -/// \brief Write samples to a binary file. -/// -/// \returns true if the samples were written successfully, false otherwise. -std::error_code SampleProfileWriterBinary::write(StringRef FName, - const FunctionSamples &S) { +std::error_code SampleProfileWriterBinary::writeBody(StringRef FName, + const FunctionSamples &S) { if (std::error_code EC = writeNameIdx(FName)) return EC; encodeULEB128(S.getTotalSamples(), OS); - encodeULEB128(S.getHeadSamples(), OS); - encodeULEB128(S.getBodySamples().size(), OS); // Emit all the body samples. + encodeULEB128(S.getBodySamples().size(), OS); for (const auto &I : S.getBodySamples()) { LineLocation Loc = I.first; const SampleRecord &Sample = I.second; @@ -158,13 +154,22 @@ std::error_code SampleProfileWriterBinary::write(StringRef FName, const FunctionSamples &CalleeSamples = J.second; encodeULEB128(Loc.LineOffset, OS); encodeULEB128(Loc.Discriminator, OS); - if (std::error_code EC = write(Loc.CalleeName, CalleeSamples)) + if (std::error_code EC = writeBody(Loc.CalleeName, CalleeSamples)) return EC; } return sampleprof_error::success; } +/// \brief Write samples of a top-level function to a binary file. +/// +/// \returns true if the samples were written successfully, false otherwise. +std::error_code SampleProfileWriterBinary::write(StringRef FName, + const FunctionSamples &S) { + encodeULEB128(S.getHeadSamples(), OS); + return writeBody(FName, S); +} + /// \brief Create a sample profile writer based on the specified format. /// /// \param Filename The file to create. diff --git a/test/Transforms/SampleProfile/Inputs/fnptr.binprof b/test/Transforms/SampleProfile/Inputs/fnptr.binprof index dc7234d8300828c853036e310bd2e83a6d651807..a074f53db945df7b0e59b7dd4b678a93ca911b89 100644 GIT binary patch delta 69 zcmd1IRQ><-!p1Krr>qE0W6n*?%wvd;GEU3S&jis)iA9+V3=Eg&a!*v%mVCs*INyem Wk>L>w1H)WyrnB=Hft<-!p1Krr>qE0WzJ2^%wvd;GEU3S&jis)iA9+V443C}GfY&~mSmi7^N59! Vk>L>w0|V39d5m+pfgGS50|3l=7PtTa -- 2.34.1