//===- InstrProf.cpp - Instrumented profiling format support --------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This file contains support for clang's instrumentation based PGO and
// coverage.
//
//===----------------------------------------------------------------------===//
#include "llvm/ProfileData/InstrProf.h"
#include "llvm/ADT/ArrayRef.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/ADT/StringRef.h"
#include "llvm/Config/config.h"
#include "llvm/IR/Constant.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/GlobalValue.h"
#include "llvm/IR/GlobalVariable.h"
#include "llvm/IR/Instruction.h"
#include "llvm/IR/LLVMContext.h"
#include "llvm/IR/MDBuilder.h"
#include "llvm/IR/Metadata.h"
#include "llvm/IR/Module.h"
#include "llvm/IR/Type.h"
#include "llvm/ProfileData/InstrProfReader.h"
#include "llvm/Support/Casting.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Compiler.h"
#include "llvm/Support/Compression.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/Endian.h"
#include "llvm/Support/Error.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/LEB128.h"
#include "llvm/Support/MathExtras.h"
#include "llvm/Support/Path.h"
#include "llvm/Support/SwapByteOrder.h"
#include "llvm/Support/VirtualFileSystem.h"
#include "llvm/TargetParser/Triple.h"
#include <algorithm>
#include <cassert>
#include <cstddef>
#include <cstdint>
#include <cstring>
#include <memory>
#include <string>
#include <system_error>
#include <type_traits>
#include <utility>
#include <vector>
using namespace llvm;
#define DEBUG_TYPE "instrprof"
static cl::opt<bool> StaticFuncFullModulePrefix(
"static-func-full-module-prefix", cl::init(true), cl::Hidden,
cl::desc("Use full module build paths in the profile counter names for "
"static functions."));
// This option is tailored to users that have different top-level directory in
// profile-gen and profile-use compilation. Users need to specific the number
// of levels to strip. A value larger than the number of directories in the
// source file will strip all the directory names and only leave the basename.
//
// Note current ThinLTO module importing for the indirect-calls assumes
// the source directory name not being stripped. A non-zero option value here
// can potentially prevent some inter-module indirect-call-promotions.
static cl::opt<unsigned> StaticFuncStripDirNamePrefix(
"static-func-strip-dirname-prefix", cl::init(0), cl::Hidden,
cl::desc("Strip specified level of directory name from source path in "
"the profile counter name for static functions."));
static std::string getInstrProfErrString(instrprof_error Err,
const std::string &ErrMsg = "") {
std::string Msg;
raw_string_ostream OS(Msg);
switch (Err) {
case instrprof_error::success:
OS << "success";
break;
case instrprof_error::eof:
OS << "end of File";
break;
case instrprof_error::unrecognized_format:
OS << "unrecognized instrumentation profile encoding format";
break;
case instrprof_error::bad_magic:
OS << "invalid instrumentation profile data (bad magic)";
break;
case instrprof_error::bad_header:
OS << "invalid instrumentation profile data (file header is corrupt)";
break;
case instrprof_error::unsupported_version:
OS << "unsupported instrumentation profile format version";
break;
case instrprof_error::unsupported_hash_type:
OS << "unsupported instrumentation profile hash type";
break;
case instrprof_error::too_large:
OS << "too much profile data";
break;
case instrprof_error::truncated:
OS << "truncated profile data";
break;
case instrprof_error::malformed:
OS << "malformed instrumentation profile data";
break;
case instrprof_error::missing_correlation_info:
OS << "debug info/binary for correlation is required";
break;
case instrprof_error::unexpected_correlation_info:
OS << "debug info/binary for correlation is not necessary";
break;
case instrprof_error::unable_to_correlate_profile:
OS << "unable to correlate profile";
break;
case instrprof_error::invalid_prof:
OS << "invalid profile created. Please file a bug "
"at: " BUG_REPORT_URL
" and include the profraw files that caused this error.";
break;
case instrprof_error::unknown_function:
OS << "no profile data available for function";
break;
case instrprof_error::hash_mismatch:
OS << "function control flow change detected (hash mismatch)";
break;
case instrprof_error::count_mismatch:
OS << "function basic block count change detected (counter mismatch)";
break;
case instrprof_error::bitmap_mismatch:
OS << "function bitmap size change detected (bitmap size mismatch)";
break;
case instrprof_error::counter_overflow:
OS << "counter overflow";
break;
case instrprof_error::value_site_count_mismatch:
OS << "function value site count change detected (counter mismatch)";
break;
case instrprof_error::compress_failed:
OS << "failed to compress data (zlib)";
break;
case instrprof_error::uncompress_failed:
OS << "failed to uncompress data (zlib)";
break;
case instrprof_error::empty_raw_profile:
OS << "empty raw profile file";
break;
case instrprof_error::zlib_unavailable:
OS << "profile uses zlib compression but the profile reader was built "
"without zlib support";
break;
case instrprof_error::raw_profile_version_mismatch:
OS << "raw profile version mismatch";
break;
case instrprof_error::counter_value_too_large:
OS << "excessively large counter value suggests corrupted profile data";
break;
}
// If optional error message is not empty, append it to the message.
if (!ErrMsg.empty())
OS << ": " << ErrMsg;
return OS.str();
}
namespace {
// FIXME: This class is only here to support the transition to llvm::Error. It
// will be removed once this transition is complete. Clients should prefer to
// deal with the Error value directly, rather than converting to error_code.
class InstrProfErrorCategoryType : public std::error_category {
const char *name() const noexcept override { return "llvm.instrprof"; }
std::string message(int IE) const override {
return getInstrProfErrString(static_cast<instrprof_error>(IE));
}
};
} // end anonymous namespace
const std::error_category &llvm::instrprof_category() {
static InstrProfErrorCategoryType ErrorCategory;
return ErrorCategory;
}
namespace {
const char *InstrProfSectNameCommon[] = {
#define INSTR_PROF_SECT_ENTRY(Kind, SectNameCommon, SectNameCoff, Prefix) \
SectNameCommon,
#include "llvm/ProfileData/InstrProfData.inc"
};
const char *InstrProfSectNameCoff[] = {
#define INSTR_PROF_SECT_ENTRY(Kind, SectNameCommon, SectNameCoff, Prefix) \
SectNameCoff,
#include "llvm/ProfileData/InstrProfData.inc"
};
const char *InstrProfSectNamePrefix[] = {
#define INSTR_PROF_SECT_ENTRY(Kind, SectNameCommon, SectNameCoff, Prefix) \
Prefix,
#include "llvm/ProfileData/InstrProfData.inc"
};
} // namespace
namespace llvm {
cl::opt<bool> DoInstrProfNameCompression(
"enable-name-compression",
cl::desc("Enable name/filename string compression"), cl::init(true));
cl::opt<bool> EnableVTableValueProfiling(
"enable-vtable-value-profiling", cl::init(false),
cl::desc("If true, the virtual table address will be instrumented to know "
"the types of a C++ pointer. The information is used in indirect "
"call promotion to do selective vtable-based comparison."));
cl::opt<bool> EnableVTableProfileUse(
"enable-vtable-profile-use", cl::init(false),
cl::desc("If ThinLTO and WPD is enabled and this option is true, vtable "
"profiles will be used by ICP pass for more efficient indirect "
"call sequence. If false, type profiles won't be used."));
std::string getInstrProfSectionName(InstrProfSectKind IPSK,
Triple::ObjectFormatType OF,
bool AddSegmentInfo) {
std::string SectName;
if (OF == Triple::MachO && AddSegmentInfo)
SectName = InstrProfSectNamePrefix[IPSK];
if (OF == Triple::COFF)
SectName += InstrProfSectNameCoff[IPSK];
else
SectName += InstrProfSectNameCommon[IPSK];
if (OF == Triple::MachO && IPSK == IPSK_data && AddSegmentInfo)
SectName += ",regular,live_support";
return SectName;
}
std::string InstrProfError::message() const {
return getInstrProfErrString(Err, Msg);
}
char InstrProfError::ID = 0;
std::string getPGOFuncName(StringRef Name, GlobalValue::LinkageTypes Linkage,
StringRef FileName,
uint64_t Version LLVM_ATTRIBUTE_UNUSED) {
// Value names may be prefixed with a binary '1' to indicate
// that the backend should not modify the symbols due to any platform
// naming convention. Do not include that '1' in the PGO profile name.
if (Name[0] == '\1')
Name = Name.substr(1);
std::string NewName = std::string(Name);
if (llvm::GlobalValue::isLocalLinkage(Linkage)) {
// For local symbols, prepend the main file name to distinguish them.
// Do not include the full path in the file name since there's no guarantee
// that it will stay the same, e.g., if the files are checked out from
// version control in different locations.
if (FileName.empty())
NewName = NewName.insert(0, "<unknown>:");
else
NewName = NewName.insert(0, FileName.str() + ":");
}
return NewName;
}
// Strip NumPrefix level of directory name from PathNameStr. If the number of
// directory separators is less than NumPrefix, strip all the directories and
// leave base file name only.
static StringRef stripDirPrefix(StringRef PathNameStr, uint32_t NumPrefix) {
uint32_t Count = NumPrefix;
uint32_t Pos = 0, LastPos = 0;
for (const auto &CI : PathNameStr) {
++Pos;
if (llvm::sys::path::is_separator(CI)) {
LastPos = Pos;
--Count;
}
if (Count == 0)
break;
}
return PathNameStr.substr(LastPos);
}
static StringRef getStrippedSourceFileName(const GlobalObject &GO) {
StringRef FileName(GO.getParent()->getSourceFileName());
uint32_t StripLevel = StaticFuncFullModulePrefix ? 0 : (uint32_t)-1;
if (StripLevel < StaticFuncStripDirNamePrefix)
StripLevel = StaticFuncStripDirNamePrefix;
if (StripLevel)
FileName = stripDirPrefix(FileName, StripLevel);
return FileName;
}
// The PGO name has the format [<filepath>;]<mangled-name> where <filepath>; is
// provided if linkage is local and is used to discriminate possibly identical
// mangled names. ";" is used because it is unlikely to be found in either
// <filepath> or <mangled-name>.
//
// Older compilers used getPGOFuncName() which has the format
// [<filepath>:]<mangled-name>. This caused trouble for Objective-C functions
// which commonly have :'s in their names. We still need to compute this name to
// lookup functions from profiles built by older compilers.
static std::string
getIRPGONameForGlobalObject(const GlobalObject &GO,
GlobalValue::LinkageTypes Linkage,
StringRef FileName) {
return GlobalValue::getGlobalIdentifier(GO.getName(), Linkage, FileName);
}
static std::optional<std::string> lookupPGONameFromMetadata(MDNode *MD) {
if (MD != nullptr) {
StringRef S = cast<MDString>(MD->getOperand(0))->getString();
return S.str();
}
return {};
}
// Returns the PGO object name. This function has some special handling
// when called in LTO optimization. The following only applies when calling in
// LTO passes (when \c InLTO is true): LTO's internalization privatizes many
// global linkage symbols. This happens after value profile annotation, but
// those internal linkage functions should not have a source prefix.
// Additionally, for ThinLTO mode, exported internal functions are promoted
// and renamed. We need to ensure that the original internal PGO name is
// used when computing the GUID that is compared against the profiled GUIDs.
// To differentiate compiler generated internal symbols from original ones,
// PGOFuncName meta data are created and attached to the original internal
// symbols in the value profile annotation step
// (PGOUseFunc::annotateIndirectCallSites). If a symbol does not have the meta
// data, its original linkage must be non-internal.
static std::string getIRPGOObjectName(const GlobalObject &GO, bool InLTO,
MDNode *PGONameMetadata) {
if (!InLTO) {
auto FileName = getStrippedSourceFileName(GO);
return getIRPGONameForGlobalObject(GO, GO.getLinkage(), FileName);
}
// In LTO mode (when InLTO is true), first check if there is a meta data.
if (auto IRPGOFuncName = lookupPGONameFromMetadata(PGONameMetadata))
return *IRPGOFuncName;
// If there is no meta data, the function must be a global before the value
// profile annotation pass. Its current linkage may be internal if it is
// internalized in LTO mode.
return getIRPGONameForGlobalObject(GO, GlobalValue::ExternalLinkage, "");
}
// Returns the IRPGO function name and does special handling when called
// in LTO optimization. See the comments of `getIRPGOObjectName` for details.
std::string getIRPGOFuncName(const Function &F, bool InLTO) {
return getIRPGOObjectName(F, InLTO, getPGOFuncNameMetadata(F));
}
// Please use getIRPGOFuncName for LLVM IR instrumentation. This function is
// for front-end (Clang, etc) instrumentation.
// The implementation is kept for profile matching from older profiles.
// This is similar to `getIRPGOFuncName` except that this function calls
// 'getPGOFuncName' to get a name and `getIRPGOFuncName` calls
// 'getIRPGONameForGlobalObject'. See the difference between two callees in the
// comments of `getIRPGONameForGlobalObject`.
std::string getPGOFuncName(const Function &F, bool InLTO, uint64_t Version) {
if (!InLTO) {
auto FileName = getStrippedSourceFileName(F);
return getPGOFuncName(F.getName(), F.getLinkage(), FileName, Version);
}
// In LTO mode (when InLTO is true), first check if there is a meta data.
if (auto PGOFuncName = lookupPGONameFromMetadata(getPGOFuncNameMetadata(F)))
return *PGOFuncName;
// If there is no meta data, the function must be a global before the value
// profile annotation pass. Its current linkage may be internal if it is
// internalized in LTO mode.
return getPGOFuncName(F.getName(), GlobalValue::ExternalLinkage, "");
}
std::string getPGOName(const GlobalVariable &V, bool InLTO) {
// PGONameMetadata should be set by compiler at profile use time
// and read by symtab creation to look up symbols corresponding to
// a MD5 hash.
return getIRPGOObjectName(V, InLTO, V.getMetadata(getPGONameMetadataName()));
}
// See getIRPGOObjectName() for a discription of the format.
std::pair<StringRef, StringRef> getParsedIRPGOName(StringRef IRPGOName) {
auto [FileName, MangledName] = IRPGOName.split(GlobalIdentifierDelimiter);
if (MangledName.empty())
return std::make_pair(StringRef(), IRPGOName);
return std::make_pair(FileName, MangledName);
}
StringRef getFuncNameWithoutPrefix(StringRef PGOFuncName, StringRef FileName) {
if (FileName.empty())
return PGOFuncName;
// Drop the file name including ':' or ';'. See getIRPGONameForGlobalObject as
// well.
if (PGOFuncName.starts_with(FileName))
PGOFuncName = PGOFuncName.drop_front(FileName.size() + 1);
return PGOFuncName;
}
// \p FuncName is the string used as profile lookup key for the function. A
// symbol is created to hold the name. Return the legalized symbol name.
std::string getPGOFuncNameVarName(StringRef FuncName,
GlobalValue::LinkageTypes Linkage) {
std::string VarName = std::string(getInstrProfNameVarPrefix());
VarName += FuncName;
if (!GlobalValue::isLocalLinkage(Linkage))
return VarName;
// Now fix up illegal chars in local VarName that may upset the assembler.
const char InvalidChars[] = "-:;<>/\"'";
size_t FoundPos = VarName.find_first_of(InvalidChars);
while (FoundPos != std::string::npos) {
VarName[FoundPos] = '_';
FoundPos = VarName.find_first_of(InvalidChars, FoundPos + 1);
}
return VarName;
}
GlobalVariable *createPGOFuncNameVar(Module &M,
GlobalValue::LinkageTypes Linkage,
StringRef PGOFuncName) {
// We generally want to match the function's linkage, but available_externally
// and extern_weak both have the wrong semantics, and anything that doesn't
// need to link across compilation units doesn't need to be visible at all.
if (Linkage == GlobalValue::ExternalWeakLinkage)
Linkage = GlobalValue::LinkOnceAnyLinkage;
else if (Linkage == GlobalValue::AvailableExternallyLinkage)
Linkage = GlobalValue::LinkOnceODRLinkage;
else if (Linkage == GlobalValue::InternalLinkage ||
Linkage == GlobalValue::ExternalLinkage)
Linkage = GlobalValue::PrivateLinkage;
auto *Value =
ConstantDataArray::getString(M.getContext(), PGOFuncName, false);
auto *FuncNameVar =
new GlobalVariable(M, Value->getType(), true, Linkage, Value,
getPGOFuncNameVarName(PGOFuncName, Linkage));
// Hide the symbol so that we correctly get a copy for each executable.
if (!GlobalValue::isLocalLinkage(FuncNameVar->getLinkage()))
FuncNameVar->setVisibility(GlobalValue::HiddenVisibility);
return FuncNameVar;
}
GlobalVariable *createPGOFuncNameVar(Function &F, StringRef PGOFuncName) {
return createPGOFuncNameVar(*F.getParent(), F.getLinkage(), PGOFuncName);
}
Error InstrProfSymtab::create(Module &M, bool InLTO) {
for (Function &F : M) {
// Function may not have a name: like using asm("") to overwrite the name.
// Ignore in this case.
if (!F.hasName())
continue;
if (Error E = addFuncWithName(F, getIRPGOFuncName(F, InLTO)))
return E;
// Also use getPGOFuncName() so that we can find records from older profiles
if (Error E = addFuncWithName(F, getPGOFuncName(F, InLTO)))
return E;
}
SmallVector<MDNode *, 2> Types;
for (GlobalVariable &G : M.globals()) {
if (!G.hasName() || !G.hasMetadata(LLVMContext::MD_type))
continue;
if (Error E = addVTableWithName(G, getPGOName(G, InLTO)))
return E;
}
Sorted = false;
finalizeSymtab();
return Error::success();
}
Error InstrProfSymtab::addVTableWithName(GlobalVariable &VTable,
StringRef VTablePGOName) {
auto NameToGUIDMap = [&](StringRef Name) -> Error {
if (Error E = addSymbolName(Name))
return E;
bool Inserted = true;
std::tie(std::ignore, Inserted) =
MD5VTableMap.try_emplace(GlobalValue::getGUID(Name), &VTable);
if (!Inserted)
LLVM_DEBUG(dbgs() << "GUID conflict within one module");
return Error::success();
};
if (Error E = NameToGUIDMap(VTablePGOName))
return E;
StringRef CanonicalName = getCanonicalName(VTablePGOName);
if (CanonicalName != VTablePGOName)
return NameToGUIDMap(CanonicalName);
return Error::success();
}
/// \c NameStrings is a string composed of one of more possibly encoded
/// sub-strings. The substrings are separated by 0 or more zero bytes. This
/// method decodes the string and calls `NameCallback` for each substring.
static Error
readAndDecodeStrings(StringRef NameStrings,
std::function<Error(StringRef)> NameCallback) {
const uint8_t *P = NameStrings.bytes_begin();
const uint8_t *EndP = NameStrings.bytes_end();
while (P < EndP) {
uint32_t N;
uint64_t UncompressedSize = decodeULEB128(P, &N);
P += N;
uint64_t CompressedSize = decodeULEB128(P, &N);
P += N;
const bool IsCompressed = (CompressedSize != 0);
SmallVector<uint8_t, 128> UncompressedNameStrings;
StringRef NameStrings;
if (IsCompressed) {
if (!llvm::compression::zlib::isAvailable())
return make_error<InstrProfError>(instrprof_error::zlib_unavailable);
if (Error E = compression::zlib::decompress(ArrayRef(P, CompressedSize),
UncompressedNameStrings,
UncompressedSize)) {
consumeError(std::move(E));
return make_error<InstrProfError>(instrprof_error::uncompress_failed);
}
P += CompressedSize;
NameStrings = toStringRef(UncompressedNameStrings);
} else {
NameStrings =
StringRef(reinterpret_cast<const char *>(P), UncompressedSize);
P += UncompressedSize;
}
// Now parse the name strings.
SmallVector<StringRef, 0> Names;
NameStrings.split(Names, getInstrProfNameSeparator());
for (StringRef &Name : Names)
if (Error E = NameCallback(Name))
return E;
while (P < EndP && *P == 0)
P++;
}
return Error::success();
}
Error InstrProfSymtab::create(StringRef NameStrings) {
return readAndDecodeStrings(
NameStrings,
std::bind(&InstrProfSymtab::addFuncName, this, std::placeholders::_1));
}
Error InstrProfSymtab::create(StringRef FuncNameStrings,
StringRef VTableNameStrings) {
if (Error E = readAndDecodeStrings(FuncNameStrings,
std::bind(&InstrProfSymtab::addFuncName,
this, std::placeholders::_1)))
return E;
return readAndDecodeStrings(
VTableNameStrings,
std::bind(&InstrProfSymtab::addVTableName, this, std::placeholders::_1));
}
Error InstrProfSymtab::initVTableNamesFromCompressedStrings(
StringRef CompressedVTableStrings) {
return readAndDecodeStrings(
CompressedVTableStrings,
std::bind(&InstrProfSymtab::addVTableName, this, std::placeholders::_1));
}
StringRef InstrProfSymtab::getCanonicalName(StringRef PGOName) {
// In ThinLTO, local function may have been promoted to global and have
// suffix ".llvm." added to the function name. We need to add the
// stripped function name to the symbol table so that we can find a match
// from profile.
//
// ".__uniq." suffix is used to differentiate internal linkage functions in
// different modules and should be kept. This is the only suffix with the
// pattern ".xxx" which is kept before matching, other suffixes similar as
// ".llvm." will be stripped.
const std::string UniqSuffix = ".__uniq.";
size_t Pos = PGOName.find(UniqSuffix);
if (Pos != StringRef::npos)
Pos += UniqSuffix.length();
else
Pos = 0;
// Search '.' after ".__uniq." if ".__uniq." exists, otherwise search '.' from
// the beginning.
Pos = PGOName.find('.', Pos);
if (Pos != StringRef::npos && Pos != 0)
return PGOName.substr(0, Pos);
return PGOName;
}
Error InstrProfSymtab::addFuncWithName(Function &F, StringRef PGOFuncName) {
auto NameToGUIDMap = [&](StringRef Name) -> Error {
if (Error E = addFuncName(Name))
return E;
MD5FuncMap.emplace_back(Function::getGUID(Name), &F);
return Error::success();
};
if (Error E = NameToGUIDMap(PGOFuncName))
return E;
StringRef CanonicalFuncName = getCanonicalName(PGOFuncName);
if (CanonicalFuncName != PGOFuncName)
return NameToGUIDMap(CanonicalFuncName);
return Error::success();
}
uint64_t InstrProfSymtab::getVTableHashFromAddress(uint64_t Address) {
// Given a runtime address, look up the hash value in the interval map, and
// fallback to value 0 if a hash value is not found.
return VTableAddrMap.lookup(Address, 0);
}
uint64_t InstrProfSymtab::getFunctionHashFromAddress(uint64_t Address) {
finalizeSymtab();
auto It = partition_point(AddrToMD5Map, [=](std::pair<uint64_t, uint64_t> A) {
return A.first < Address;
});
// Raw function pointer collected by value profiler may be from
// external functions that are not instrumented. They won't have
// mapping data to be used by the deserializer. Force the value to
// be 0 in this case.
if (It != AddrToMD5Map.end() && It->first == Address)
return (uint64_t)It->second;
return 0;
}
void InstrProfSymtab::dumpNames(raw_ostream &OS) const {
SmallVector<StringRef, 0> Sorted(NameTab.keys());
llvm::sort(Sorted);
for (StringRef S : Sorted)
OS << S << '\n';
}
Error collectGlobalObjectNameStrings(ArrayRef<std::string> NameStrs,
bool DoCompression, std::string &Result) {
assert(!NameStrs.empty() && "No name data to emit");
uint8_t Header[20], *P = Header;
std::string UncompressedNameStrings =
join(NameStrs.begin(), NameStrs.end(), getInstrProfNameSeparator());
assert(StringRef(UncompressedNameStrings)
.count(getInstrProfNameSeparator()) == (NameStrs.size() - 1) &&
"PGO name is invalid (contains separator token)");
unsigned EncLen = encodeULEB128(UncompressedNameStrings.length(), P);
P += EncLen;
auto WriteStringToResult = [&](size_t CompressedLen, StringRef InputStr) {
EncLen = encodeULEB128(CompressedLen, P);
P += EncLen;
char *HeaderStr = reinterpret_cast<char *>(&Header[0]);
unsigned HeaderLen = P - &Header[0];
Result.append(HeaderStr, HeaderLen);
Result += InputStr;
return Error::success();
};
if (!DoCompression) {
return WriteStringToResult(0, UncompressedNameStrings);
}
SmallVector<uint8_t, 128> CompressedNameStrings;
compression::zlib::compress(arrayRefFromStringRef(UncompressedNameStrings),
CompressedNameStrings,
compression::zlib::BestSizeCompression);
return WriteStringToResult(CompressedNameStrings.size(),
toStringRef(CompressedNameStrings));
}
StringRef getPGOFuncNameVarInitializer(GlobalVariable *NameVar) {
auto *Arr = cast<ConstantDataArray>(NameVar->getInitializer());
StringRef NameStr =
Arr->isCString() ? Arr->getAsCString() : Arr->getAsString();
return NameStr;
}
Error collectPGOFuncNameStrings(ArrayRef<GlobalVariable *> NameVars,
std::string &Result, bool DoCompression) {
std::vector<std::string> NameStrs;
for (auto *NameVar : NameVars) {
NameStrs.push_back(std::string(getPGOFuncNameVarInitializer(NameVar)));
}
return collectGlobalObjectNameStrings(
NameStrs, compression::zlib::isAvailable() && DoCompression, Result);
}
Error collectVTableStrings(ArrayRef<GlobalVariable *> VTables,
std::string &Result, bool DoCompression) {
std::vector<std::string> VTableNameStrs;
for (auto *VTable : VTables)
VTableNameStrs.push_back(getPGOName(*VTable));
return collectGlobalObjectNameStrings(
VTableNameStrs, compression::zlib::isAvailable() && DoCompression,
Result);
}
void InstrProfRecord::accumulateCounts(CountSumOrPercent &Sum) const {
uint64_t FuncSum = 0;
Sum.NumEntries += Counts.size();
for (uint64_t Count : Counts)
FuncSum += Count;
Sum.CountSum += FuncSum;
for (uint32_t VK = IPVK_First; VK <= IPVK_Last; ++VK) {
uint64_t KindSum = 0;
uint32_t NumValueSites = getNumValueSites(VK);
for (size_t I = 0; I < NumValueSites; ++I) {
for (const auto &V : getValueArrayForSite(VK, I))
KindSum += V.Count;
}
Sum.ValueCounts[VK] += KindSum;
}
}
void InstrProfValueSiteRecord::overlap(InstrProfValueSiteRecord &Input,
uint32_t ValueKind,
OverlapStats &Overlap,
OverlapStats &FuncLevelOverlap) {
this->sortByTargetValues();
Input.sortByTargetValues();
double Score = 0.0f, FuncLevelScore = 0.0f;
auto I = ValueData.begin();
auto IE = ValueData.end();
auto J = Input.ValueData.begin();
auto JE = Input.ValueData.end();
while (I != IE && J != JE) {
if (I->Value == J->Value) {
Score += OverlapStats::score(I->Count, J->Count,
Overlap.Base.ValueCounts[ValueKind],
Overlap.Test.ValueCounts[ValueKind]);
FuncLevelScore += OverlapStats::score(
I->Count, J->Count, FuncLevelOverlap.Base.ValueCounts[ValueKind],
FuncLevelOverlap.Test.ValueCounts[ValueKind]);
++I;
} else if (I->Value < J->Value) {
++I;
continue;
}
++J;
}
Overlap.Overlap.ValueCounts[ValueKind] += Score;
FuncLevelOverlap.Overlap.ValueCounts[ValueKind] += FuncLevelScore;
}
// Return false on mismatch.
void InstrProfRecord::overlapValueProfData(uint32_t ValueKind,
InstrProfRecord &Other,
OverlapStats &Overlap,
OverlapStats &FuncLevelOverlap) {
uint32_t ThisNumValueSites = getNumValueSites(ValueKind);
assert(ThisNumValueSites == Other.getNumValueSites(ValueKind));
if (!ThisNumValueSites)
return;
std::vector<InstrProfValueSiteRecord> &ThisSiteRecords =
getOrCreateValueSitesForKind(ValueKind);
MutableArrayRef<InstrProfValueSiteRecord> OtherSiteRecords =
Other.getValueSitesForKind(ValueKind);
for (uint32_t I = 0; I < ThisNumValueSites; I++)
ThisSiteRecords[I].overlap(OtherSiteRecords[I], ValueKind, Overlap,
FuncLevelOverlap);
}
void InstrProfRecord::overlap(InstrProfRecord &Other, OverlapStats &Overlap,
OverlapStats &FuncLevelOverlap,
uint64_t ValueCutoff) {
// FuncLevel CountSum for other should already computed and nonzero.
assert(FuncLevelOverlap.Test.CountSum >= 1.0f);
accumulateCounts(FuncLevelOverlap.Base);
bool Mismatch = (Counts.size() != Other.Counts.size());
// Check if the value profiles mismatch.
if (!Mismatch) {
for (uint32_t Kind = IPVK_First; Kind <= IPVK_Last; ++Kind) {
uint32_t ThisNumValueSites = getNumValueSites(Kind);
uint32_t OtherNumValueSites = Other.getNumValueSites(Kind);
if (ThisNumValueSites != OtherNumValueSites) {
Mismatch = true;
break;
}
}
}
if (Mismatch) {
Overlap.addOneMismatch(FuncLevelOverlap.Test);
return;
}
// Compute overlap for value counts.
for (uint32_t Kind = IPVK_First; Kind <= IPVK_Last; ++Kind)
overlapValueProfData(Kind, Other, Overlap, FuncLevelOverlap);
double Score = 0.0;
uint64_t MaxCount = 0;
// Compute overlap for edge counts.
for (size_t I = 0, E = Other.Counts.size(); I < E; ++I) {
Score += OverlapStats::score(Counts[I], Other.Counts[I],
Overlap.Base.CountSum, Overlap.Test.CountSum);
MaxCount = std::max(Other.Counts[I], MaxCount);
}
Overlap.Overlap.CountSum += Score;
Overlap.Overlap.NumEntries += 1;
if (MaxCount >= ValueCutoff) {
double FuncScore = 0.0;
for (size_t I = 0, E = Other.Counts.size(); I < E; ++I)
FuncScore += OverlapStats::score(Counts[I], Other.Counts[I],
FuncLevelOverlap.Base.CountSum,
FuncLevelOverlap.Test.CountSum);
FuncLevelOverlap.Overlap.CountSum = FuncScore;
FuncLevelOverlap.Overlap.NumEntries = Other.Counts.size();
FuncLevelOverlap.Valid = true;
}
}
void InstrProfValueSiteRecord::merge(InstrProfValueSiteRecord &Input,
uint64_t Weight,
function_ref<void(instrprof_error)> Warn) {
this->sortByTargetValues();
Input.sortByTargetValues();
auto I = ValueData.begin();
auto IE = ValueData.end();
std::vector<InstrProfValueData> Merged;
Merged.reserve(std::max(ValueData.size(), Input.ValueData.size()));
for (const InstrProfValueData &J : Input.ValueData) {
while (I != IE && I->Value < J.Value) {
Merged.push_back(*I);
++I;
}
if (I != IE && I->Value == J.Value) {
bool Overflowed;
I->Count = SaturatingMultiplyAdd(J.Count, Weight, I->Count, &Overflowed);
if (Overflowed)
Warn(instrprof_error::counter_overflow);
Merged.push_back(*I);
++I;
continue;
}
Merged.push_back(J);
}
Merged.insert(Merged.end(), I, IE);
ValueData = std::move(Merged);
}
void InstrProfValueSiteRecord::scale(uint64_t N, uint64_t D,
function_ref<void(instrprof_error)> Warn) {
for (InstrProfValueData &I : ValueData) {
bool Overflowed;
I.Count = SaturatingMultiply(I.Count, N, &Overflowed) / D;
if (Overflowed)
Warn(instrprof_error::counter_overflow);
}
}
// Merge Value Profile data from Src record to this record for ValueKind.
// Scale merged value counts by \p Weight.
void InstrProfRecord::mergeValueProfData(
uint32_t ValueKind, InstrProfRecord &Src, uint64_t Weight,
function_ref<void(instrprof_error)> Warn) {
uint32_t ThisNumValueSites = getNumValueSites(ValueKind);
uint32_t OtherNumValueSites = Src.getNumValueSites(ValueKind);
if (ThisNumValueSites != OtherNumValueSites) {
Warn(instrprof_error::value_site_count_mismatch);
return;
}
if (!ThisNumValueSites)
return;
std::vector<InstrProfValueSiteRecord> &ThisSiteRecords =
getOrCreateValueSitesForKind(ValueKind);
MutableArrayRef<InstrProfValueSiteRecord> OtherSiteRecords =
Src.getValueSitesForKind(ValueKind);
for (uint32_t I = 0; I < ThisNumValueSites; I++)
ThisSiteRecords[I].merge(OtherSiteRecords[I], Weight, Warn);
}
void InstrProfRecord::merge(InstrProfRecord &Other, uint64_t Weight,
function_ref<void(instrprof_error)> Warn) {
// If the number of counters doesn't match we either have bad data
// or a hash collision.
if (Counts.size() != Other.Counts.size()) {
Warn(instrprof_error::count_mismatch);
return;
}
// Special handling of the first count as the PseudoCount.
CountPseudoKind OtherKind = Other.getCountPseudoKind();
CountPseudoKind ThisKind = getCountPseudoKind();
if (OtherKind != NotPseudo || ThisKind != NotPseudo) {
// We don't allow the merge of a profile with pseudo counts and
// a normal profile (i.e. without pesudo counts).
// Profile supplimenation should be done after the profile merge.
if (OtherKind == NotPseudo || ThisKind == NotPseudo) {
Warn(instrprof_error::count_mismatch);
return;
}
if (OtherKind == PseudoHot || ThisKind == PseudoHot)
setPseudoCount(PseudoHot);
else
setPseudoCount(PseudoWarm);
return;
}
for (size_t I = 0, E = Other.Counts.size(); I < E; ++I) {
bool Overflowed;
uint64_t Value =
SaturatingMultiplyAdd(Other.Counts[I], Weight, Counts[I], &Overflowed);
if (Value > getInstrMaxCountValue()) {
Value = getInstrMaxCountValue();
Overflowed = true;
}
Counts[I] = Value;
if (Overflowed)
Warn(instrprof_error::counter_overflow);
}
// If the number of bitmap bytes doesn't match we either have bad data
// or a hash collision.
if (BitmapBytes.size() != Other.BitmapBytes.size()) {
Warn(instrprof_error::bitmap_mismatch);
return;
}
// Bitmap bytes are merged by simply ORing them together.
for (size_t I = 0, E = Other.BitmapBytes.size(); I < E; ++I) {
BitmapBytes[I] = Other.BitmapBytes[I] | BitmapBytes[I];
}
for (uint32_t Kind = IPVK_First; Kind <= IPVK_Last; ++Kind)
mergeValueProfData(Kind, Other, Weight, Warn);
}
void InstrProfRecord::scaleValueProfData(
uint32_t ValueKind, uint64_t N, uint64_t D,
function_ref<void(instrprof_error)> Warn) {
for (auto &R : getValueSitesForKind(ValueKind))
R.scale(N, D, Warn);
}
void InstrProfRecord::scale(uint64_t N, uint64_t D,
function_ref<void(instrprof_error)> Warn) {
assert(D != 0 && "D cannot be 0");
for (auto &Count : this->Counts) {
bool Overflowed;
Count = SaturatingMultiply(Count, N, &Overflowed) / D;
if (Count > getInstrMaxCountValue()) {
Count = getInstrMaxCountValue();
Overflowed = true;
}
if (Overflowed)
Warn(instrprof_error::counter_overflow);
}
for (uint32_t Kind = IPVK_First; Kind <= IPVK_Last; ++Kind)
scaleValueProfData(Kind, N, D, Warn);
}
// Map indirect call target name hash to name string.
uint64_t InstrProfRecord::remapValue(uint64_t Value, uint32_t ValueKind,
InstrProfSymtab *SymTab) {
if (!SymTab)
return Value;
if (ValueKind == IPVK_IndirectCallTarget)
return SymTab->getFunctionHashFromAddress(Value);
if (ValueKind == IPVK_VTableTarget)
return SymTab->getVTableHashFromAddress(Value);
return Value;
}
void InstrProfRecord::addValueData(uint32_t ValueKind, uint32_t Site,
ArrayRef<InstrProfValueData> VData,
InstrProfSymtab *ValueMap) {
// Remap values.
std::vector<InstrProfValueData> RemappedVD;
RemappedVD.reserve(VData.size());
for (const auto &V : VData) {
uint64_t NewValue = remapValue(V.Value, ValueKind, ValueMap);
RemappedVD.push_back({NewValue, V.Count});
}
std::vector<InstrProfValueSiteRecord> &ValueSites =
getOrCreateValueSitesForKind(ValueKind);
assert(ValueSites.size() == Site);
// Add a new value site with remapped value profiling data.
ValueSites.emplace_back(std::move(RemappedVD));
}
void TemporalProfTraceTy::createBPFunctionNodes(
ArrayRef<TemporalProfTraceTy> Traces, std::vector<BPFunctionNode> &Nodes,
bool RemoveOutlierUNs) {
using IDT = BPFunctionNode::IDT;
using UtilityNodeT = BPFunctionNode::UtilityNodeT;
UtilityNodeT MaxUN = 0;
DenseMap<IDT, size_t> IdToFirstTimestamp;
DenseMap<IDT, UtilityNodeT> IdToFirstUN;
DenseMap<IDT, SmallVector<UtilityNodeT>> IdToUNs;
// TODO: We need to use the Trace.Weight field to give more weight to more
// important utilities
for (auto &Trace : Traces) {
size_t CutoffTimestamp = 1;
for (size_t Timestamp = 0; Timestamp < Trace.FunctionNameRefs.size();
Timestamp++) {
IDT Id = Trace.FunctionNameRefs[Timestamp];
auto [It, WasInserted] = IdToFirstTimestamp.try_emplace(Id, Timestamp);
if (!WasInserted)
It->getSecond() = std::min<size_t>(It->getSecond(), Timestamp);
if (Timestamp >= CutoffTimestamp) {
++MaxUN;
CutoffTimestamp = 2 * Timestamp;
}
IdToFirstUN.try_emplace(Id, MaxUN);
}
for (auto &[Id, FirstUN] : IdToFirstUN)
for (auto UN = FirstUN; UN <= MaxUN; ++UN)
IdToUNs[Id].push_back(UN);
++MaxUN;
IdToFirstUN.clear();
}
if (RemoveOutlierUNs) {
DenseMap<UtilityNodeT, unsigned> UNFrequency;
for (auto &[Id, UNs] : IdToUNs)
for (auto &UN : UNs)
++UNFrequency[UN];
// Filter out utility nodes that are too infrequent or too prevalent to make
// BalancedPartitioning more effective.
for (auto &[Id, UNs] : IdToUNs)
llvm::erase_if(UNs, [&](auto &UN) {
return UNFrequency[UN] <= 1 || 2 * UNFrequency[UN] > IdToUNs.size();
});
}
for (auto &[Id, UNs] : IdToUNs)
Nodes.emplace_back(Id, UNs);
// Since BalancedPartitioning is sensitive to the initial order, we explicitly
// order nodes by their earliest timestamp.
llvm::sort(Nodes, [&](auto &L, auto &R) {
return std::make_pair(IdToFirstTimestamp[L.Id], L.Id) <
std::make_pair(IdToFirstTimestamp[R.Id], R.Id);
});
}
#define INSTR_PROF_COMMON_API_IMPL
#include "llvm/ProfileData/InstrProfData.inc"
/*!
* ValueProfRecordClosure Interface implementation for InstrProfRecord
* class. These C wrappers are used as adaptors so that C++ code can be
* invoked as callbacks.
*/
uint32_t getNumValueKindsInstrProf(const void *Record) {
return reinterpret_cast<const InstrProfRecord *>(Record)->getNumValueKinds();
}
uint32_t getNumValueSitesInstrProf(const void *Record, uint32_t VKind) {
return reinterpret_cast<const InstrProfRecord *>(Record)
->getNumValueSites(VKind);
}
uint32_t getNumValueDataInstrProf(const void *Record, uint32_t VKind) {
return reinterpret_cast<const InstrProfRecord *>(Record)
->getNumValueData(VKind);
}
uint32_t getNumValueDataForSiteInstrProf(const void *R, uint32_t VK,
uint32_t S) {
const auto *IPR = reinterpret_cast<const InstrProfRecord *>(R);
return IPR->getValueArrayForSite(VK, S).size();
}
void getValueForSiteInstrProf(const void *R, InstrProfValueData *Dst,
uint32_t K, uint32_t S) {
const auto *IPR = reinterpret_cast<const InstrProfRecord *>(R);
llvm::copy(IPR->getValueArrayForSite(K, S), Dst);
}
ValueProfData *allocValueProfDataInstrProf(size_t TotalSizeInBytes) {
ValueProfData *VD =
(ValueProfData *)(new (::operator new(TotalSizeInBytes)) ValueProfData());
memset(VD, 0, TotalSizeInBytes);
return VD;
}
static ValueProfRecordClosure InstrProfRecordClosure = {
nullptr,
getNumValueKindsInstrProf,
getNumValueSitesInstrProf,
getNumValueDataInstrProf,
getNumValueDataForSiteInstrProf,
nullptr,
getValueForSiteInstrProf,
allocValueProfDataInstrProf};
// Wrapper implementation using the closure mechanism.
uint32_t ValueProfData::getSize(const InstrProfRecord &Record) {
auto Closure = InstrProfRecordClosure;
Closure.Record = &Record;
return getValueProfDataSize(&Closure);
}
// Wrapper implementation using the closure mechanism.
std::unique_ptr<ValueProfData>
ValueProfData::serializeFrom(const InstrProfRecord &Record) {
InstrProfRecordClosure.Record = &Record;
std::unique_ptr<ValueProfData> VPD(
serializeValueProfDataFrom(&InstrProfRecordClosure, nullptr));
return VPD;
}
void ValueProfRecord::deserializeTo(InstrProfRecord &Record,
InstrProfSymtab *SymTab) {
Record.reserveSites(Kind, NumValueSites);
InstrProfValueData *ValueData = getValueProfRecordValueData(this);
for (uint64_t VSite = 0; VSite < NumValueSites; ++VSite) {
uint8_t ValueDataCount = this->SiteCountArray[VSite];
ArrayRef<InstrProfValueData> VDs(ValueData, ValueDataCount);
Record.addValueData(Kind, VSite, VDs, SymTab);
ValueData += ValueDataCount;
}
}
// For writing/serializing, Old is the host endianness, and New is
// byte order intended on disk. For Reading/deserialization, Old
// is the on-disk source endianness, and New is the host endianness.
void ValueProfRecord::swapBytes(llvm::endianness Old, llvm::endianness New) {
using namespace support;
if (Old == New)
return;
if (llvm::endianness::native != Old) {
sys::swapByteOrder<uint32_t>(NumValueSites);
sys::swapByteOrder<uint32_t>(Kind);
}
uint32_t ND = getValueProfRecordNumValueData(this);
InstrProfValueData *VD = getValueProfRecordValueData(this);
// No need to swap byte array: SiteCountArrray.
for (uint32_t I = 0; I < ND; I++) {
sys::swapByteOrder<uint64_t>(VD[I].Value);
sys::swapByteOrder<uint64_t>(VD[I].Count);
}
if (llvm::endianness::native == Old) {
sys::swapByteOrder<uint32_t>(NumValueSites);
sys::swapByteOrder<uint32_t>(Kind);
}
}
void ValueProfData::deserializeTo(InstrProfRecord &Record,
InstrProfSymtab *SymTab) {
if (NumValueKinds == 0)
return;
ValueProfRecord *VR = getFirstValueProfRecord(this);
for (uint32_t K = 0; K < NumValueKinds; K++) {
VR->deserializeTo(Record, SymTab);
VR = getValueProfRecordNext(VR);
}
}
static std::unique_ptr<ValueProfData> allocValueProfData(uint32_t TotalSize) {
return std::unique_ptr<ValueProfData>(new (::operator new(TotalSize))
ValueProfData());
}
Error ValueProfData::checkIntegrity() {
if (NumValueKinds > IPVK_Last + 1)
return make_error<InstrProfError>(
instrprof_error::malformed, "number of value profile kinds is invalid");
// Total size needs to be multiple of quadword size.
if (TotalSize % sizeof(uint64_t))
return make_error<InstrProfError>(
instrprof_error::malformed, "total size is not multiples of quardword");
ValueProfRecord *VR = getFirstValueProfRecord(this);
for (uint32_t K = 0; K < this->NumValueKinds; K++) {
if (VR->Kind > IPVK_Last)
return make_error<InstrProfError>(instrprof_error::malformed,
"value kind is invalid");
VR = getValueProfRecordNext(VR);
if ((char *)VR - (char *)this > (ptrdiff_t)TotalSize)
return make_error<InstrProfError>(
instrprof_error::malformed,
"value profile address is greater than total size");
}
return Error::success();
}
Expected<std::unique_ptr<ValueProfData>>
ValueProfData::getValueProfData(const unsigned char *D,
const unsigned char *const BufferEnd,
llvm::endianness Endianness) {
using namespace support;
if (D + sizeof(ValueProfData) > BufferEnd)
return make_error<InstrProfError>(instrprof_error::truncated);
const unsigned char *Header = D;
uint32_t TotalSize = endian::readNext<uint32_t>(Header, Endianness);
if (D + TotalSize > BufferEnd)
return make_error<InstrProfError>(instrprof_error::too_large);
std::unique_ptr<ValueProfData> VPD = allocValueProfData(TotalSize);
memcpy(VPD.get(), D, TotalSize);
// Byte swap.
VPD->swapBytesToHost(Endianness);
Error E = VPD->checkIntegrity();
if (E)
return std::move(E);
return std::move(VPD);
}
void ValueProfData::swapBytesToHost(llvm::endianness Endianness) {
using namespace support;
if (Endianness == llvm::endianness::native)
return;
sys::swapByteOrder<uint32_t>(TotalSize);
sys::swapByteOrder<uint32_t>(NumValueKinds);
ValueProfRecord *VR = getFirstValueProfRecord(this);
for (uint32_t K = 0; K < NumValueKinds; K++) {
VR->swapBytes(Endianness, llvm::endianness::native);
VR = getValueProfRecordNext(VR);
}
}
void ValueProfData::swapBytesFromHost(llvm::endianness Endianness) {
using namespace support;
if (Endianness == llvm::endianness::native)
return;
ValueProfRecord *VR = getFirstValueProfRecord(this);
for (uint32_t K = 0; K < NumValueKinds; K++) {
ValueProfRecord *NVR = getValueProfRecordNext(VR);
VR->swapBytes(llvm::endianness::native, Endianness);
VR = NVR;
}
sys::swapByteOrder<uint32_t>(TotalSize);
sys::swapByteOrder<uint32_t>(NumValueKinds);
}
void annotateValueSite(Module &M, Instruction &Inst,
const InstrProfRecord &InstrProfR,
InstrProfValueKind ValueKind, uint32_t SiteIdx,
uint32_t MaxMDCount) {
auto VDs = InstrProfR.getValueArrayForSite(ValueKind, SiteIdx);
if (VDs.empty())
return;
uint64_t Sum = 0;
for (const InstrProfValueData &V : VDs)
Sum = SaturatingAdd(Sum, V.Count);
annotateValueSite(M, Inst, VDs, Sum, ValueKind, MaxMDCount);
}
void annotateValueSite(Module &M, Instruction &Inst,
ArrayRef<InstrProfValueData> VDs,
uint64_t Sum, InstrProfValueKind ValueKind,
uint32_t MaxMDCount) {
if (VDs.empty())
return;
LLVMContext &Ctx = M.getContext();
MDBuilder MDHelper(Ctx);
SmallVector<Metadata *, 3> Vals;
// Tag
Vals.push_back(MDHelper.createString("VP"));
// Value Kind
Vals.push_back(MDHelper.createConstant(
ConstantInt::get(Type::getInt32Ty(Ctx), ValueKind)));
// Total Count
Vals.push_back(
MDHelper.createConstant(ConstantInt::get(Type::getInt64Ty(Ctx), Sum)));
// Value Profile Data
uint32_t MDCount = MaxMDCount;
for (const auto &VD : VDs) {
Vals.push_back(MDHelper.createConstant(
ConstantInt::get(Type::getInt64Ty(Ctx), VD.Value)));
Vals.push_back(MDHelper.createConstant(
ConstantInt::get(Type::getInt64Ty(Ctx), VD.Count)));
if (--MDCount == 0)
break;
}
Inst.setMetadata(LLVMContext::MD_prof, MDNode::get(Ctx, Vals));
}
MDNode *mayHaveValueProfileOfKind(const Instruction &Inst,
InstrProfValueKind ValueKind) {
MDNode *MD = Inst.getMetadata(LLVMContext::MD_prof);
if (!MD)
return nullptr;
if (MD->getNumOperands() < 5)
return nullptr;
MDString *Tag = cast<MDString>(MD->getOperand(0));
if (!Tag || Tag->getString() != "VP")
return nullptr;
// Now check kind:
ConstantInt *KindInt = mdconst::dyn_extract<ConstantInt>(MD->getOperand(1));
if (!KindInt)
return nullptr;
if (KindInt->getZExtValue() != ValueKind)
return nullptr;
return MD;
}
SmallVector<InstrProfValueData, 4>
getValueProfDataFromInst(const Instruction &Inst, InstrProfValueKind ValueKind,
uint32_t MaxNumValueData, uint64_t &TotalC,
bool GetNoICPValue) {
// Four inline elements seem to work well in practice. With MaxNumValueData,
// this array won't grow very big anyway.
SmallVector<InstrProfValueData, 4> ValueData;
MDNode *MD = mayHaveValueProfileOfKind(Inst, ValueKind);
if (!MD)
return ValueData;
const unsigned NOps = MD->getNumOperands();
// Get total count
ConstantInt *TotalCInt = mdconst::dyn_extract<ConstantInt>(MD->getOperand(2));
if (!TotalCInt)
return ValueData;
TotalC = TotalCInt->getZExtValue();
ValueData.reserve((NOps - 3) / 2);
for (unsigned I = 3; I < NOps; I += 2) {
if (ValueData.size() >= MaxNumValueData)
break;
ConstantInt *Value = mdconst::dyn_extract<ConstantInt>(MD->getOperand(I));
ConstantInt *Count =
mdconst::dyn_extract<ConstantInt>(MD->getOperand(I + 1));
if (!Value || !Count) {
ValueData.clear();
return ValueData;
}
uint64_t CntValue = Count->getZExtValue();
if (!GetNoICPValue && (CntValue == NOMORE_ICP_MAGICNUM))
continue;
InstrProfValueData V;
V.Value = Value->getZExtValue();
V.Count = CntValue;
ValueData.push_back(V);
}
return ValueData;
}
MDNode *getPGOFuncNameMetadata(const Function &F) {
return F.getMetadata(getPGOFuncNameMetadataName());
}
static void createPGONameMetadata(GlobalObject &GO, StringRef MetadataName,
StringRef PGOName) {
// Only for internal linkage functions or global variables. The name is not
// the same as PGO name for these global objects.
if (GO.getName() == PGOName)
return;
// Don't create duplicated metadata.
if (GO.getMetadata(MetadataName))
return;
LLVMContext &C = GO.getContext();
MDNode *N = MDNode::get(C, MDString::get(C, PGOName));
GO.setMetadata(MetadataName, N);
}
void createPGOFuncNameMetadata(Function &F, StringRef PGOFuncName) {
return createPGONameMetadata(F, getPGOFuncNameMetadataName(), PGOFuncName);
}
void createPGONameMetadata(GlobalObject &GO, StringRef PGOName) {
return createPGONameMetadata(GO, getPGONameMetadataName(), PGOName);
}
bool needsComdatForCounter(const GlobalObject &GO, const Module &M) {
if (GO.hasComdat())
return true;
if (!Triple(M.getTargetTriple()).supportsCOMDAT())
return false;
// See createPGOFuncNameVar for more details. To avoid link errors, profile
// counters for function with available_externally linkage needs to be changed
// to linkonce linkage. On ELF based systems, this leads to weak symbols to be
// created. Without using comdat, duplicate entries won't be removed by the
// linker leading to increased data segement size and raw profile size. Even
// worse, since the referenced counter from profile per-function data object
// will be resolved to the common strong definition, the profile counts for
// available_externally functions will end up being duplicated in raw profile
// data. This can result in distorted profile as the counts of those dups
// will be accumulated by the profile merger.
GlobalValue::LinkageTypes Linkage = GO.getLinkage();
if (Linkage != GlobalValue::ExternalWeakLinkage &&
Linkage != GlobalValue::AvailableExternallyLinkage)
return false;
return true;
}
// Check if INSTR_PROF_RAW_VERSION_VAR is defined.
bool isIRPGOFlagSet(const Module *M) {
const GlobalVariable *IRInstrVar =
M->getNamedGlobal(INSTR_PROF_QUOTE(INSTR_PROF_RAW_VERSION_VAR));
if (!IRInstrVar || IRInstrVar->hasLocalLinkage())
return false;
// For CSPGO+LTO, this variable might be marked as non-prevailing and we only
// have the decl.
if (IRInstrVar->isDeclaration())
return true;
// Check if the flag is set.
if (!IRInstrVar->hasInitializer())
return false;
auto *InitVal = dyn_cast_or_null<ConstantInt>(IRInstrVar->getInitializer());
if (!InitVal)
return false;
return (InitVal->getZExtValue() & VARIANT_MASK_IR_PROF) != 0;
}
// Check if we can safely rename this Comdat function.
bool canRenameComdatFunc(const Function &F, bool CheckAddressTaken) {
if (F.getName().empty())
return false;
if (!needsComdatForCounter(F, *(F.getParent())))
return false;
// Unsafe to rename the address-taken function (which can be used in
// function comparison).
if (CheckAddressTaken && F.hasAddressTaken())
return false;
// Only safe to do if this function may be discarded if it is not used
// in the compilation unit.
if (!GlobalValue::isDiscardableIfUnused(F.getLinkage()))
return false;
// For AvailableExternallyLinkage functions.
if (!F.hasComdat()) {
assert(F.getLinkage() == GlobalValue::AvailableExternallyLinkage);
return true;
}
return true;
}
// Create the variable for the profile file name.
void createProfileFileNameVar(Module &M, StringRef InstrProfileOutput) {
if (InstrProfileOutput.empty())
return;
Constant *ProfileNameConst =
ConstantDataArray::getString(M.getContext(), InstrProfileOutput, true);
GlobalVariable *ProfileNameVar = new GlobalVariable(
M, ProfileNameConst->getType(), true, GlobalValue::WeakAnyLinkage,
ProfileNameConst, INSTR_PROF_QUOTE(INSTR_PROF_PROFILE_NAME_VAR));
ProfileNameVar->setVisibility(GlobalValue::HiddenVisibility);
Triple TT(M.getTargetTriple());
if (TT.supportsCOMDAT()) {
ProfileNameVar->setLinkage(GlobalValue::ExternalLinkage);
ProfileNameVar->setComdat(M.getOrInsertComdat(
StringRef(INSTR_PROF_QUOTE(INSTR_PROF_PROFILE_NAME_VAR))));
}
}
Error OverlapStats::accumulateCounts(const std::string &BaseFilename,
const std::string &TestFilename,
bool IsCS) {
auto GetProfileSum = [IsCS](const std::string &Filename,
CountSumOrPercent &Sum) -> Error {
// This function is only used from llvm-profdata that doesn't use any kind
// of VFS. Just create a default RealFileSystem to read profiles.
auto FS = vfs::getRealFileSystem();
auto ReaderOrErr = InstrProfReader::create(Filename, *FS);
if (Error E = ReaderOrErr.takeError()) {
return E;
}
auto Reader = std::move(ReaderOrErr.get());
Reader->accumulateCounts(Sum, IsCS);
return Error::success();
};
auto Ret = GetProfileSum(BaseFilename, Base);
if (Ret)
return Ret;
Ret = GetProfileSum(TestFilename, Test);
if (Ret)
return Ret;
this->BaseFilename = &BaseFilename;
this->TestFilename = &TestFilename;
Valid = true;
return Error::success();
}
void OverlapStats::addOneMismatch(const CountSumOrPercent &MismatchFunc) {
Mismatch.NumEntries += 1;
Mismatch.CountSum += MismatchFunc.CountSum / Test.CountSum;
for (unsigned I = 0; I < IPVK_Last - IPVK_First + 1; I++) {
if (Test.ValueCounts[I] >= 1.0f)
Mismatch.ValueCounts[I] +=
MismatchFunc.ValueCounts[I] / Test.ValueCounts[I];
}
}
void OverlapStats::addOneUnique(const CountSumOrPercent &UniqueFunc) {
Unique.NumEntries += 1;
Unique.CountSum += UniqueFunc.CountSum / Test.CountSum;
for (unsigned I = 0; I < IPVK_Last - IPVK_First + 1; I++) {
if (Test.ValueCounts[I] >= 1.0f)
Unique.ValueCounts[I] += UniqueFunc.ValueCounts[I] / Test.ValueCounts[I];
}
}
void OverlapStats::dump(raw_fd_ostream &OS) const {
if (!Valid)
return;
const char *EntryName =
(Level == ProgramLevel ? "functions" : "edge counters");
if (Level == ProgramLevel) {
OS << "Profile overlap infomation for base_profile: " << *BaseFilename
<< " and test_profile: " << *TestFilename << "\nProgram level:\n";
} else {
OS << "Function level:\n"
<< " Function: " << FuncName << " (Hash=" << FuncHash << ")\n";
}
OS << " # of " << EntryName << " overlap: " << Overlap.NumEntries << "\n";
if (Mismatch.NumEntries)
OS << " # of " << EntryName << " mismatch: " << Mismatch.NumEntries
<< "\n";
if (Unique.NumEntries)
OS << " # of " << EntryName
<< " only in test_profile: " << Unique.NumEntries << "\n";
OS << " Edge profile overlap: " << format("%.3f%%", Overlap.CountSum * 100)
<< "\n";
if (Mismatch.NumEntries)
OS << " Mismatched count percentage (Edge): "
<< format("%.3f%%", Mismatch.CountSum * 100) << "\n";
if (Unique.NumEntries)
OS << " Percentage of Edge profile only in test_profile: "
<< format("%.3f%%", Unique.CountSum * 100) << "\n";
OS << " Edge profile base count sum: " << format("%.0f", Base.CountSum)
<< "\n"
<< " Edge profile test count sum: " << format("%.0f", Test.CountSum)
<< "\n";
for (unsigned I = 0; I < IPVK_Last - IPVK_First + 1; I++) {
if (Base.ValueCounts[I] < 1.0f && Test.ValueCounts[I] < 1.0f)
continue;
char ProfileKindName[20] = {0};
switch (I) {
case IPVK_IndirectCallTarget:
strncpy(ProfileKindName, "IndirectCall", 19);
break;
case IPVK_MemOPSize:
strncpy(ProfileKindName, "MemOP", 19);
break;
case IPVK_VTableTarget:
strncpy(ProfileKindName, "VTable", 19);
break;
default:
snprintf(ProfileKindName, 19, "VP[%d]", I);
break;
}
OS << " " << ProfileKindName
<< " profile overlap: " << format("%.3f%%", Overlap.ValueCounts[I] * 100)
<< "\n";
if (Mismatch.NumEntries)
OS << " Mismatched count percentage (" << ProfileKindName
<< "): " << format("%.3f%%", Mismatch.ValueCounts[I] * 100) << "\n";
if (Unique.NumEntries)
OS << " Percentage of " << ProfileKindName
<< " profile only in test_profile: "
<< format("%.3f%%", Unique.ValueCounts[I] * 100) << "\n";
OS << " " << ProfileKindName
<< " profile base count sum: " << format("%.0f", Base.ValueCounts[I])
<< "\n"
<< " " << ProfileKindName
<< " profile test count sum: " << format("%.0f", Test.ValueCounts[I])
<< "\n";
}
}
namespace IndexedInstrProf {
Expected<Header> Header::readFromBuffer(const unsigned char *Buffer) {
using namespace support;
static_assert(std::is_standard_layout_v<Header>,
"Use standard layout for Header for simplicity");
Header H;
H.Magic = endian::readNext<uint64_t, llvm::endianness::little>(Buffer);
// Check the magic number.
if (H.Magic != IndexedInstrProf::Magic)
return make_error<InstrProfError>(instrprof_error::bad_magic);
// Read the version.
H.Version = endian::readNext<uint64_t, llvm::endianness::little>(Buffer);
if (H.getIndexedProfileVersion() >
IndexedInstrProf::ProfVersion::CurrentVersion)
return make_error<InstrProfError>(instrprof_error::unsupported_version);
static_assert(IndexedInstrProf::ProfVersion::CurrentVersion == Version12,
"Please update the reader as needed when a new field is added "
"or when indexed profile version gets bumped.");
Buffer += sizeof(uint64_t); // Skip Header.Unused field.
H.HashType = endian::readNext<uint64_t, llvm::endianness::little>(Buffer);
H.HashOffset = endian::readNext<uint64_t, llvm::endianness::little>(Buffer);
if (H.getIndexedProfileVersion() >= 8)
H.MemProfOffset =
endian::readNext<uint64_t, llvm::endianness::little>(Buffer);
if (H.getIndexedProfileVersion() >= 9)
H.BinaryIdOffset =
endian::readNext<uint64_t, llvm::endianness::little>(Buffer);
// Version 11 is handled by this condition.
if (H.getIndexedProfileVersion() >= 10)
H.TemporalProfTracesOffset =
endian::readNext<uint64_t, llvm::endianness::little>(Buffer);
if (H.getIndexedProfileVersion() >= 12)
H.VTableNamesOffset =
endian::readNext<uint64_t, llvm::endianness::little>(Buffer);
return H;
}
uint64_t Header::getIndexedProfileVersion() const {
return GET_VERSION(Version);
}
size_t Header::size() const {
switch (getIndexedProfileVersion()) {
// To retain backward compatibility, new fields must be appended to the end
// of the header, and byte offset of existing fields shouldn't change when
// indexed profile version gets incremented.
static_assert(
IndexedInstrProf::ProfVersion::CurrentVersion == Version12,
"Please update the size computation below if a new field has "
"been added to the header; for a version bump without new "
"fields, add a case statement to fall through to the latest version.");
case 12ull:
return 72;
case 11ull:
[[fallthrough]];
case 10ull:
return 64;
case 9ull:
return 56;
case 8ull:
return 48;
default: // Version7 (when the backwards compatible header was introduced).
return 40;
}
}
} // namespace IndexedInstrProf
} // end namespace llvm