llvm/llvm/lib/Transforms/Instrumentation/PGOCtxProfFlattening.cpp

//===- PGOCtxProfFlattening.cpp - Contextual Instr. Flattening ------------===//
//
// 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
//
//===----------------------------------------------------------------------===//
//
// Flattens the contextual profile and lowers it to MD_prof.
// This should happen after all IPO (which is assumed to have maintained the
// contextual profile) happened. Flattening consists of summing the values at
// the same index of the counters belonging to all the contexts of a function.
// The lowering consists of materializing the counter values to function
// entrypoint counts and branch probabilities.
//
// This pass also removes contextual instrumentation, which has been kept around
// to facilitate its functionality.
//
//===----------------------------------------------------------------------===//

#include "llvm/Transforms/Instrumentation/PGOCtxProfFlattening.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/ScopeExit.h"
#include "llvm/Analysis/CtxProfAnalysis.h"
#include "llvm/Analysis/ProfileSummaryInfo.h"
#include "llvm/IR/Analysis.h"
#include "llvm/IR/CFG.h"
#include "llvm/IR/Dominators.h"
#include "llvm/IR/Instructions.h"
#include "llvm/IR/IntrinsicInst.h"
#include "llvm/IR/Module.h"
#include "llvm/IR/PassManager.h"
#include "llvm/IR/ProfileSummary.h"
#include "llvm/ProfileData/ProfileCommon.h"
#include "llvm/Transforms/Instrumentation/PGOInstrumentation.h"
#include "llvm/Transforms/Scalar/DCE.h"
#include "llvm/Transforms/Utils/BasicBlockUtils.h"
#include <deque>

usingnamespacellvm;

namespace {

class ProfileAnnotator final { … };

[[maybe_unused]] bool areAllBBsReachable(const Function &F,
                                         FunctionAnalysisManager &FAM) { … }

void clearColdFunctionProfile(Function &F) { … }

void removeInstrumentation(Function &F) { … }

} // namespace

PreservedAnalyses PGOCtxProfFlatteningPass::run(Module &M,
                                                ModuleAnalysisManager &MAM) { … }