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-rw-r--r--lib/CodeGen/CodeGenPGO.cpp364
1 files changed, 122 insertions, 242 deletions
diff --git a/lib/CodeGen/CodeGenPGO.cpp b/lib/CodeGen/CodeGenPGO.cpp
index b233e3c7d75e..24b035d67598 100644
--- a/lib/CodeGen/CodeGenPGO.cpp
+++ b/lib/CodeGen/CodeGenPGO.cpp
@@ -13,8 +13,10 @@
#include "CodeGenPGO.h"
#include "CodeGenFunction.h"
+#include "CoverageMappingGen.h"
#include "clang/AST/RecursiveASTVisitor.h"
#include "clang/AST/StmtVisitor.h"
+#include "llvm/IR/Intrinsics.h"
#include "llvm/IR/MDBuilder.h"
#include "llvm/ProfileData/InstrProfReader.h"
#include "llvm/Support/Endian.h"
@@ -24,8 +26,9 @@
using namespace clang;
using namespace CodeGen;
-void CodeGenPGO::setFuncName(llvm::Function *Fn) {
- RawFuncName = Fn->getName();
+void CodeGenPGO::setFuncName(StringRef Name,
+ llvm::GlobalValue::LinkageTypes Linkage) {
+ StringRef RawFuncName = Name;
// Function names may be prefixed with a binary '1' to indicate
// that the backend should not modify the symbols due to any platform
@@ -33,172 +36,44 @@ void CodeGenPGO::setFuncName(llvm::Function *Fn) {
if (RawFuncName[0] == '\1')
RawFuncName = RawFuncName.substr(1);
- if (!Fn->hasLocalLinkage()) {
- PrefixedFuncName.reset(new std::string(RawFuncName));
- return;
+ FuncName = RawFuncName;
+ 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 (CGM.getCodeGenOpts().MainFileName.empty())
+ FuncName = FuncName.insert(0, "<unknown>:");
+ else
+ FuncName = FuncName.insert(0, CGM.getCodeGenOpts().MainFileName + ":");
}
- // 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.
- PrefixedFuncName.reset(new std::string(CGM.getCodeGenOpts().MainFileName));
- if (PrefixedFuncName->empty())
- PrefixedFuncName->assign("<unknown>");
- PrefixedFuncName->append(":");
- PrefixedFuncName->append(RawFuncName);
-}
-
-static llvm::Function *getRegisterFunc(CodeGenModule &CGM) {
- return CGM.getModule().getFunction("__llvm_profile_register_functions");
-}
-
-static llvm::BasicBlock *getOrInsertRegisterBB(CodeGenModule &CGM) {
- // Don't do this for Darwin. compiler-rt uses linker magic.
- if (CGM.getTarget().getTriple().isOSDarwin())
- return nullptr;
-
- // Only need to insert this once per module.
- if (llvm::Function *RegisterF = getRegisterFunc(CGM))
- return &RegisterF->getEntryBlock();
-
- // Construct the function.
- auto *VoidTy = llvm::Type::getVoidTy(CGM.getLLVMContext());
- auto *RegisterFTy = llvm::FunctionType::get(VoidTy, false);
- auto *RegisterF = llvm::Function::Create(RegisterFTy,
- llvm::GlobalValue::InternalLinkage,
- "__llvm_profile_register_functions",
- &CGM.getModule());
- RegisterF->setUnnamedAddr(true);
- if (CGM.getCodeGenOpts().DisableRedZone)
- RegisterF->addFnAttr(llvm::Attribute::NoRedZone);
-
- // Construct and return the entry block.
- auto *BB = llvm::BasicBlock::Create(CGM.getLLVMContext(), "", RegisterF);
- CGBuilderTy Builder(BB);
- Builder.CreateRetVoid();
- return BB;
-}
-
-static llvm::Constant *getOrInsertRuntimeRegister(CodeGenModule &CGM) {
- auto *VoidTy = llvm::Type::getVoidTy(CGM.getLLVMContext());
- auto *VoidPtrTy = llvm::Type::getInt8PtrTy(CGM.getLLVMContext());
- auto *RuntimeRegisterTy = llvm::FunctionType::get(VoidTy, VoidPtrTy, false);
- return CGM.getModule().getOrInsertFunction("__llvm_profile_register_function",
- RuntimeRegisterTy);
-}
-
-static bool isMachO(const CodeGenModule &CGM) {
- return CGM.getTarget().getTriple().isOSBinFormatMachO();
-}
-
-static StringRef getCountersSection(const CodeGenModule &CGM) {
- return isMachO(CGM) ? "__DATA,__llvm_prf_cnts" : "__llvm_prf_cnts";
-}
-
-static StringRef getNameSection(const CodeGenModule &CGM) {
- return isMachO(CGM) ? "__DATA,__llvm_prf_names" : "__llvm_prf_names";
+ // If we're generating a profile, create a variable for the name.
+ if (CGM.getCodeGenOpts().ProfileInstrGenerate)
+ createFuncNameVar(Linkage);
}
-static StringRef getDataSection(const CodeGenModule &CGM) {
- return isMachO(CGM) ? "__DATA,__llvm_prf_data" : "__llvm_prf_data";
-}
-
-llvm::GlobalVariable *CodeGenPGO::buildDataVar() {
- // Create name variable.
- llvm::LLVMContext &Ctx = CGM.getLLVMContext();
- auto *VarName = llvm::ConstantDataArray::getString(Ctx, getFuncName(),
- false);
- auto *Name = new llvm::GlobalVariable(CGM.getModule(), VarName->getType(),
- true, VarLinkage, VarName,
- getFuncVarName("name"));
- Name->setSection(getNameSection(CGM));
- Name->setAlignment(1);
-
- // Create data variable.
- auto *Int32Ty = llvm::Type::getInt32Ty(Ctx);
- auto *Int64Ty = llvm::Type::getInt64Ty(Ctx);
- auto *Int8PtrTy = llvm::Type::getInt8PtrTy(Ctx);
- auto *Int64PtrTy = llvm::Type::getInt64PtrTy(Ctx);
- llvm::Type *DataTypes[] = {
- Int32Ty, Int32Ty, Int64Ty, Int8PtrTy, Int64PtrTy
- };
- auto *DataTy = llvm::StructType::get(Ctx, makeArrayRef(DataTypes));
- llvm::Constant *DataVals[] = {
- llvm::ConstantInt::get(Int32Ty, getFuncName().size()),
- llvm::ConstantInt::get(Int32Ty, NumRegionCounters),
- llvm::ConstantInt::get(Int64Ty, FunctionHash),
- llvm::ConstantExpr::getBitCast(Name, Int8PtrTy),
- llvm::ConstantExpr::getBitCast(RegionCounters, Int64PtrTy)
- };
- auto *Data =
- new llvm::GlobalVariable(CGM.getModule(), DataTy, true, VarLinkage,
- llvm::ConstantStruct::get(DataTy, DataVals),
- getFuncVarName("data"));
-
- // All the data should be packed into an array in its own section.
- Data->setSection(getDataSection(CGM));
- Data->setAlignment(8);
-
- // Hide all these symbols so that we correctly get a copy for each
- // executable. The profile format expects names and counters to be
- // contiguous, so references into shared objects would be invalid.
- if (!llvm::GlobalValue::isLocalLinkage(VarLinkage)) {
- Name->setVisibility(llvm::GlobalValue::HiddenVisibility);
- Data->setVisibility(llvm::GlobalValue::HiddenVisibility);
- RegionCounters->setVisibility(llvm::GlobalValue::HiddenVisibility);
- }
-
- // Make sure the data doesn't get deleted.
- CGM.addUsedGlobal(Data);
- return Data;
+void CodeGenPGO::setFuncName(llvm::Function *Fn) {
+ setFuncName(Fn->getName(), Fn->getLinkage());
}
-void CodeGenPGO::emitInstrumentationData() {
- if (!RegionCounters)
- return;
-
- // Build the data.
- auto *Data = buildDataVar();
-
- // Register the data.
- auto *RegisterBB = getOrInsertRegisterBB(CGM);
- if (!RegisterBB)
- return;
- CGBuilderTy Builder(RegisterBB->getTerminator());
- auto *VoidPtrTy = llvm::Type::getInt8PtrTy(CGM.getLLVMContext());
- Builder.CreateCall(getOrInsertRuntimeRegister(CGM),
- Builder.CreateBitCast(Data, VoidPtrTy));
-}
-
-llvm::Function *CodeGenPGO::emitInitialization(CodeGenModule &CGM) {
- if (!CGM.getCodeGenOpts().ProfileInstrGenerate)
- return nullptr;
-
- assert(CGM.getModule().getFunction("__llvm_profile_init") == nullptr &&
- "profile initialization already emitted");
-
- // Get the function to call at initialization.
- llvm::Constant *RegisterF = getRegisterFunc(CGM);
- if (!RegisterF)
- return nullptr;
-
- // Create the initialization function.
- auto *VoidTy = llvm::Type::getVoidTy(CGM.getLLVMContext());
- auto *F = llvm::Function::Create(llvm::FunctionType::get(VoidTy, false),
- llvm::GlobalValue::InternalLinkage,
- "__llvm_profile_init", &CGM.getModule());
- F->setUnnamedAddr(true);
- F->addFnAttr(llvm::Attribute::NoInline);
- if (CGM.getCodeGenOpts().DisableRedZone)
- F->addFnAttr(llvm::Attribute::NoRedZone);
-
- // Add the basic block and the necessary calls.
- CGBuilderTy Builder(llvm::BasicBlock::Create(CGM.getLLVMContext(), "", F));
- Builder.CreateCall(RegisterF);
- Builder.CreateRetVoid();
-
- return F;
+void CodeGenPGO::createFuncNameVar(llvm::GlobalValue::LinkageTypes Linkage) {
+ // Usually, we want to match the function's linkage, but
+ // available_externally and extern_weak both have the wrong semantics.
+ if (Linkage == llvm::GlobalValue::ExternalWeakLinkage)
+ Linkage = llvm::GlobalValue::LinkOnceAnyLinkage;
+ else if (Linkage == llvm::GlobalValue::AvailableExternallyLinkage)
+ Linkage = llvm::GlobalValue::LinkOnceODRLinkage;
+
+ auto *Value =
+ llvm::ConstantDataArray::getString(CGM.getLLVMContext(), FuncName, false);
+ FuncNameVar =
+ new llvm::GlobalVariable(CGM.getModule(), Value->getType(), true, Linkage,
+ Value, "__llvm_profile_name_" + FuncName);
+
+ // Hide the symbol so that we correctly get a copy for each executable.
+ if (!llvm::GlobalValue::isLocalLinkage(FuncNameVar->getLinkage()))
+ FuncNameVar->setVisibility(llvm::GlobalValue::HiddenVisibility);
}
namespace {
@@ -778,33 +653,18 @@ uint64_t PGOHash::finalize() {
return endian::read<uint64_t, little, unaligned>(Result);
}
-static void emitRuntimeHook(CodeGenModule &CGM) {
- const char *const RuntimeVarName = "__llvm_profile_runtime";
- const char *const RuntimeUserName = "__llvm_profile_runtime_user";
- if (CGM.getModule().getGlobalVariable(RuntimeVarName))
- return;
-
- // Declare the runtime hook.
- llvm::LLVMContext &Ctx = CGM.getLLVMContext();
- auto *Int32Ty = llvm::Type::getInt32Ty(Ctx);
- auto *Var = new llvm::GlobalVariable(CGM.getModule(), Int32Ty, false,
- llvm::GlobalValue::ExternalLinkage,
- nullptr, RuntimeVarName);
-
- // Make a function that uses it.
- auto *User = llvm::Function::Create(llvm::FunctionType::get(Int32Ty, false),
- llvm::GlobalValue::LinkOnceODRLinkage,
- RuntimeUserName, &CGM.getModule());
- User->addFnAttr(llvm::Attribute::NoInline);
- if (CGM.getCodeGenOpts().DisableRedZone)
- User->addFnAttr(llvm::Attribute::NoRedZone);
- CGBuilderTy Builder(llvm::BasicBlock::Create(CGM.getLLVMContext(), "", User));
- auto *Load = Builder.CreateLoad(Var);
- Builder.CreateRet(Load);
-
- // Create a use of the function. Now the definition of the runtime variable
- // should get pulled in, along with any static initializears.
- CGM.addUsedGlobal(User);
+void CodeGenPGO::checkGlobalDecl(GlobalDecl GD) {
+ // Make sure we only emit coverage mapping for one constructor/destructor.
+ // Clang emits several functions for the constructor and the destructor of
+ // a class. Every function is instrumented, but we only want to provide
+ // coverage for one of them. Because of that we only emit the coverage mapping
+ // for the base constructor/destructor.
+ if ((isa<CXXConstructorDecl>(GD.getDecl()) &&
+ GD.getCtorType() != Ctor_Base) ||
+ (isa<CXXDestructorDecl>(GD.getDecl()) &&
+ GD.getDtorType() != Dtor_Base)) {
+ SkipCoverageMapping = true;
+ }
}
void CodeGenPGO::assignRegionCounters(const Decl *D, llvm::Function *Fn) {
@@ -814,28 +674,12 @@ void CodeGenPGO::assignRegionCounters(const Decl *D, llvm::Function *Fn) {
return;
if (D->isImplicit())
return;
+ CGM.ClearUnusedCoverageMapping(D);
setFuncName(Fn);
- // Set the linkage for variables based on the function linkage. Usually, we
- // want to match it, but available_externally and extern_weak both have the
- // wrong semantics.
- VarLinkage = Fn->getLinkage();
- switch (VarLinkage) {
- case llvm::GlobalValue::ExternalWeakLinkage:
- VarLinkage = llvm::GlobalValue::LinkOnceAnyLinkage;
- break;
- case llvm::GlobalValue::AvailableExternallyLinkage:
- VarLinkage = llvm::GlobalValue::LinkOnceODRLinkage;
- break;
- default:
- break;
- }
-
mapRegionCounters(D);
- if (InstrumentRegions) {
- emitRuntimeHook(CGM);
- emitCounterVariables();
- }
+ if (CGM.getCodeGenOpts().CoverageMapping)
+ emitCounterRegionMapping(D);
if (PGOReader) {
SourceManager &SM = CGM.getContext().getSourceManager();
loadRegionCounts(PGOReader, SM.isInMainFile(D->getLocation()));
@@ -860,6 +704,56 @@ void CodeGenPGO::mapRegionCounters(const Decl *D) {
FunctionHash = Walker.Hash.finalize();
}
+void CodeGenPGO::emitCounterRegionMapping(const Decl *D) {
+ if (SkipCoverageMapping)
+ return;
+ // Don't map the functions inside the system headers
+ auto Loc = D->getBody()->getLocStart();
+ if (CGM.getContext().getSourceManager().isInSystemHeader(Loc))
+ return;
+
+ std::string CoverageMapping;
+ llvm::raw_string_ostream OS(CoverageMapping);
+ CoverageMappingGen MappingGen(*CGM.getCoverageMapping(),
+ CGM.getContext().getSourceManager(),
+ CGM.getLangOpts(), RegionCounterMap.get());
+ MappingGen.emitCounterMapping(D, OS);
+ OS.flush();
+
+ if (CoverageMapping.empty())
+ return;
+
+ CGM.getCoverageMapping()->addFunctionMappingRecord(
+ FuncNameVar, FuncName, FunctionHash, CoverageMapping);
+}
+
+void
+CodeGenPGO::emitEmptyCounterMapping(const Decl *D, StringRef FuncName,
+ llvm::GlobalValue::LinkageTypes Linkage) {
+ if (SkipCoverageMapping)
+ return;
+ setFuncName(FuncName, Linkage);
+
+ // Don't map the functions inside the system headers
+ auto Loc = D->getBody()->getLocStart();
+ if (CGM.getContext().getSourceManager().isInSystemHeader(Loc))
+ return;
+
+ std::string CoverageMapping;
+ llvm::raw_string_ostream OS(CoverageMapping);
+ CoverageMappingGen MappingGen(*CGM.getCoverageMapping(),
+ CGM.getContext().getSourceManager(),
+ CGM.getLangOpts());
+ MappingGen.emitEmptyMapping(D, OS);
+ OS.flush();
+
+ if (CoverageMapping.empty())
+ return;
+
+ CGM.getCoverageMapping()->addFunctionMappingRecord(
+ FuncNameVar, FuncName, FunctionHash, CoverageMapping);
+}
+
void CodeGenPGO::computeRegionCounts(const Decl *D) {
StmtCountMap.reset(new llvm::DenseMap<const Stmt *, uint64_t>);
ComputeRegionCounts Walker(*StmtCountMap, *this);
@@ -891,50 +785,36 @@ CodeGenPGO::applyFunctionAttributes(llvm::IndexedInstrProfReader *PGOReader,
Fn->addFnAttr(llvm::Attribute::Cold);
}
-void CodeGenPGO::emitCounterVariables() {
- llvm::LLVMContext &Ctx = CGM.getLLVMContext();
- llvm::ArrayType *CounterTy = llvm::ArrayType::get(llvm::Type::getInt64Ty(Ctx),
- NumRegionCounters);
- RegionCounters =
- new llvm::GlobalVariable(CGM.getModule(), CounterTy, false, VarLinkage,
- llvm::Constant::getNullValue(CounterTy),
- getFuncVarName("counters"));
- RegionCounters->setAlignment(8);
- RegionCounters->setSection(getCountersSection(CGM));
-}
-
void CodeGenPGO::emitCounterIncrement(CGBuilderTy &Builder, unsigned Counter) {
- if (!RegionCounters)
+ if (!CGM.getCodeGenOpts().ProfileInstrGenerate || !RegionCounterMap)
return;
- llvm::Value *Addr =
- Builder.CreateConstInBoundsGEP2_64(RegionCounters, 0, Counter);
- llvm::Value *Count = Builder.CreateLoad(Addr, "pgocount");
- Count = Builder.CreateAdd(Count, Builder.getInt64(1));
- Builder.CreateStore(Count, Addr);
+ if (!Builder.GetInsertPoint())
+ return;
+ auto *I8PtrTy = llvm::Type::getInt8PtrTy(CGM.getLLVMContext());
+ Builder.CreateCall4(CGM.getIntrinsic(llvm::Intrinsic::instrprof_increment),
+ llvm::ConstantExpr::getBitCast(FuncNameVar, I8PtrTy),
+ Builder.getInt64(FunctionHash),
+ Builder.getInt32(NumRegionCounters),
+ Builder.getInt32(Counter));
}
void CodeGenPGO::loadRegionCounts(llvm::IndexedInstrProfReader *PGOReader,
bool IsInMainFile) {
CGM.getPGOStats().addVisited(IsInMainFile);
- RegionCounts.reset(new std::vector<uint64_t>);
- uint64_t Hash;
- if (PGOReader->getFunctionCounts(getFuncName(), Hash, *RegionCounts)) {
- CGM.getPGOStats().addMissing(IsInMainFile);
- RegionCounts.reset();
- } else if (Hash != FunctionHash ||
- RegionCounts->size() != NumRegionCounters) {
- CGM.getPGOStats().addMismatched(IsInMainFile);
- RegionCounts.reset();
+ RegionCounts.clear();
+ if (std::error_code EC =
+ PGOReader->getFunctionCounts(FuncName, FunctionHash, RegionCounts)) {
+ if (EC == llvm::instrprof_error::unknown_function)
+ CGM.getPGOStats().addMissing(IsInMainFile);
+ else if (EC == llvm::instrprof_error::hash_mismatch)
+ CGM.getPGOStats().addMismatched(IsInMainFile);
+ else if (EC == llvm::instrprof_error::malformed)
+ // TODO: Consider a more specific warning for this case.
+ CGM.getPGOStats().addMismatched(IsInMainFile);
+ RegionCounts.clear();
}
}
-void CodeGenPGO::destroyRegionCounters() {
- RegionCounterMap.reset();
- StmtCountMap.reset();
- RegionCounts.reset();
- RegionCounters = nullptr;
-}
-
/// \brief Calculate what to divide by to scale weights.
///
/// Given the maximum weight, calculate a divisor that will scale all the