forked from OSchip/llvm-project
122 lines
4.3 KiB
C++
122 lines
4.3 KiB
C++
//===--- CodeGenPGO.h - PGO Instrumentation for LLVM CodeGen ----*- C++ -*-===//
|
|
//
|
|
// The LLVM Compiler Infrastructure
|
|
//
|
|
// This file is distributed under the University of Illinois Open Source
|
|
// License. See LICENSE.TXT for details.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
//
|
|
// Instrumentation-based profile-guided optimization
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#ifndef LLVM_CLANG_LIB_CODEGEN_CODEGENPGO_H
|
|
#define LLVM_CLANG_LIB_CODEGEN_CODEGENPGO_H
|
|
|
|
#include "CGBuilder.h"
|
|
#include "CodeGenModule.h"
|
|
#include "CodeGenTypes.h"
|
|
#include "clang/Frontend/CodeGenOptions.h"
|
|
#include "llvm/ProfileData/InstrProfReader.h"
|
|
#include <array>
|
|
#include <memory>
|
|
|
|
namespace clang {
|
|
namespace CodeGen {
|
|
|
|
/// Per-function PGO state.
|
|
class CodeGenPGO {
|
|
private:
|
|
CodeGenModule &CGM;
|
|
std::string FuncName;
|
|
llvm::GlobalVariable *FuncNameVar;
|
|
|
|
std::array <unsigned, llvm::IPVK_Last + 1> NumValueSites;
|
|
unsigned NumRegionCounters;
|
|
uint64_t FunctionHash;
|
|
std::unique_ptr<llvm::DenseMap<const Stmt *, unsigned>> RegionCounterMap;
|
|
std::unique_ptr<llvm::DenseMap<const Stmt *, uint64_t>> StmtCountMap;
|
|
std::unique_ptr<llvm::InstrProfRecord> ProfRecord;
|
|
std::vector<uint64_t> RegionCounts;
|
|
uint64_t CurrentRegionCount;
|
|
|
|
public:
|
|
CodeGenPGO(CodeGenModule &CGM)
|
|
: CGM(CGM), NumValueSites({{0}}), NumRegionCounters(0), FunctionHash(0),
|
|
CurrentRegionCount(0) {}
|
|
|
|
/// Whether or not we have PGO region data for the current function. This is
|
|
/// false both when we have no data at all and when our data has been
|
|
/// discarded.
|
|
bool haveRegionCounts() const { return !RegionCounts.empty(); }
|
|
|
|
/// Return the counter value of the current region.
|
|
uint64_t getCurrentRegionCount() const { return CurrentRegionCount; }
|
|
|
|
/// Set the counter value for the current region. This is used to keep track
|
|
/// of changes to the most recent counter from control flow and non-local
|
|
/// exits.
|
|
void setCurrentRegionCount(uint64_t Count) { CurrentRegionCount = Count; }
|
|
|
|
/// Check if an execution count is known for a given statement. If so, return
|
|
/// true and put the value in Count; else return false.
|
|
Optional<uint64_t> getStmtCount(const Stmt *S) {
|
|
if (!StmtCountMap)
|
|
return None;
|
|
auto I = StmtCountMap->find(S);
|
|
if (I == StmtCountMap->end())
|
|
return None;
|
|
return I->second;
|
|
}
|
|
|
|
/// If the execution count for the current statement is known, record that
|
|
/// as the current count.
|
|
void setCurrentStmt(const Stmt *S) {
|
|
if (auto Count = getStmtCount(S))
|
|
setCurrentRegionCount(*Count);
|
|
}
|
|
|
|
/// Assign counters to regions and configure them for PGO of a given
|
|
/// function. Does nothing if instrumentation is not enabled and either
|
|
/// generates global variables or associates PGO data with each of the
|
|
/// counters depending on whether we are generating or using instrumentation.
|
|
void assignRegionCounters(GlobalDecl GD, llvm::Function *Fn);
|
|
/// Emit a coverage mapping range with a counter zero
|
|
/// for an unused declaration.
|
|
void emitEmptyCounterMapping(const Decl *D, StringRef FuncName,
|
|
llvm::GlobalValue::LinkageTypes Linkage);
|
|
// Insert instrumentation or attach profile metadata at value sites
|
|
void valueProfile(CGBuilderTy &Builder, uint32_t ValueKind,
|
|
llvm::Instruction *ValueSite, llvm::Value *ValuePtr);
|
|
private:
|
|
void setFuncName(llvm::Function *Fn);
|
|
void setFuncName(StringRef Name, llvm::GlobalValue::LinkageTypes Linkage);
|
|
void mapRegionCounters(const Decl *D);
|
|
void computeRegionCounts(const Decl *D);
|
|
void applyFunctionAttributes(llvm::IndexedInstrProfReader *PGOReader,
|
|
llvm::Function *Fn);
|
|
void loadRegionCounts(llvm::IndexedInstrProfReader *PGOReader,
|
|
bool IsInMainFile);
|
|
bool skipRegionMappingForDecl(const Decl *D);
|
|
void emitCounterRegionMapping(const Decl *D);
|
|
|
|
public:
|
|
void emitCounterIncrement(CGBuilderTy &Builder, const Stmt *S,
|
|
llvm::Value *StepV);
|
|
|
|
/// Return the region count for the counter at the given index.
|
|
uint64_t getRegionCount(const Stmt *S) {
|
|
if (!RegionCounterMap)
|
|
return 0;
|
|
if (!haveRegionCounts())
|
|
return 0;
|
|
return RegionCounts[(*RegionCounterMap)[S]];
|
|
}
|
|
};
|
|
|
|
} // end namespace CodeGen
|
|
} // end namespace clang
|
|
|
|
#endif
|