BlockFrequencyInfo.cpp | Explore in Territory

//===- BlockFrequencyInfo.cpp - Block Frequency Analysis ------------------===//
//
// 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
//
//===----------------------------------------------------------------------===//
//
// Loops should be simplified before this analysis.
//
//===----------------------------------------------------------------------===//

#include "llvm/Analysis/BlockFrequencyInfo.h"
#include "llvm/ADT/APInt.h"
#include "llvm/ADT/iterator.h"
#include "llvm/Analysis/BlockFrequencyInfoImpl.h"
#include "llvm/Analysis/BranchProbabilityInfo.h"
#include "llvm/Analysis/LoopInfo.h"
#include "llvm/IR/CFG.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/PassManager.h"
#include "llvm/InitializePasses.h"
#include "llvm/Pass.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/GraphWriter.h"
#include "llvm/Support/raw_ostream.h"
#include <cassert>
#include <optional>
#include <string>

usingnamespacellvm;

#define DEBUG_TYPE …

static cl::opt<GVDAGType> ViewBlockFreqPropagationDAG(
    "view-block-freq-propagation-dags", cl::Hidden,
    cl::desc("Pop up a window to show a dag displaying how block "
             "frequencies propagation through the CFG."),
    cl::values(clEnumValN(GVDT_None, "none", "do not display graphs."),
               clEnumValN(GVDT_Fraction, "fraction",
                          "display a graph using the "
                          "fractional block frequency representation."),
               clEnumValN(GVDT_Integer, "integer",
                          "display a graph using the raw "
                          "integer fractional block frequency representation."),
               clEnumValN(GVDT_Count, "count", "display a graph using the real "
                                               "profile count if available.")));

namespace llvm {
cl::opt<std::string>
    ViewBlockFreqFuncName("view-bfi-func-name", cl::Hidden,
                          cl::desc("The option to specify "
                                   "the name of the function "
                                   "whose CFG will be displayed."));

cl::opt<unsigned>
    ViewHotFreqPercent("view-hot-freq-percent", cl::init(10), cl::Hidden,
                       cl::desc("An integer in percent used to specify "
                                "the hot blocks/edges to be displayed "
                                "in red: a block or edge whose frequency "
                                "is no less than the max frequency of the "
                                "function multiplied by this percent."));

// Command line option to turn on CFG dot or text dump after profile annotation.
cl::opt<PGOViewCountsType> PGOViewCounts(
    "pgo-view-counts", cl::Hidden,
    cl::desc("A boolean option to show CFG dag or text with "
             "block profile counts and branch probabilities "
             "right after PGO profile annotation step. The "
             "profile counts are computed using branch "
             "probabilities from the runtime profile data and "
             "block frequency propagation algorithm. To view "
             "the raw counts from the profile, use option "
             "-pgo-view-raw-counts instead. To limit graph "
             "display to only one function, use filtering option "
             "-view-bfi-func-name."),
    cl::values(clEnumValN(PGOVCT_None, "none", "do not show."),
               clEnumValN(PGOVCT_Graph, "graph", "show a graph."),
               clEnumValN(PGOVCT_Text, "text", "show in text.")));

static cl::opt<bool> PrintBFI("print-bfi", cl::init(false), cl::Hidden,
                              cl::desc("Print the block frequency info."));

cl::opt<std::string>
    PrintBFIFuncName("print-bfi-func-name", cl::Hidden,
                     cl::desc("The option to specify the name of the function "
                              "whose block frequency info is printed."));
} // namespace llvm

namespace llvm {

static GVDAGType getGVDT() { … }

template <>
struct GraphTraits<BlockFrequencyInfo *> { … };

BFIDOTGTraitsBase;

template <>
struct DOTGraphTraits<BlockFrequencyInfo *> : public BFIDOTGTraitsBase { … };

} // end namespace llvm

BlockFrequencyInfo::BlockFrequencyInfo() = default;

BlockFrequencyInfo::BlockFrequencyInfo(const Function &F,
                                       const BranchProbabilityInfo &BPI,
                                       const LoopInfo &LI) { … }

BlockFrequencyInfo::BlockFrequencyInfo(BlockFrequencyInfo &&Arg)
    : … { … }

BlockFrequencyInfo &BlockFrequencyInfo::operator=(BlockFrequencyInfo &&RHS) { … }

// Explicitly define the default constructor otherwise it would be implicitly
// defined at the first ODR-use which is the BFI member in the
// LazyBlockFrequencyInfo header.  The dtor needs the BlockFrequencyInfoImpl
// template instantiated which is not available in the header.
BlockFrequencyInfo::~BlockFrequencyInfo() = default;

bool BlockFrequencyInfo::invalidate(Function &F, const PreservedAnalyses &PA,
                                    FunctionAnalysisManager::Invalidator &) { … }

void BlockFrequencyInfo::calculate(const Function &F,
                                   const BranchProbabilityInfo &BPI,
                                   const LoopInfo &LI) { … }

BlockFrequency BlockFrequencyInfo::getBlockFreq(const BasicBlock *BB) const { … }

std::optional<uint64_t>
BlockFrequencyInfo::getBlockProfileCount(const BasicBlock *BB,
                                         bool AllowSynthetic) const { … }

std::optional<uint64_t>
BlockFrequencyInfo::getProfileCountFromFreq(BlockFrequency Freq) const { … }

bool BlockFrequencyInfo::isIrrLoopHeader(const BasicBlock *BB) { … }

void BlockFrequencyInfo::setBlockFreq(const BasicBlock *BB,
                                      BlockFrequency Freq) { … }

void BlockFrequencyInfo::setBlockFreqAndScale(
    const BasicBlock *ReferenceBB, BlockFrequency Freq,
    SmallPtrSetImpl<BasicBlock *> &BlocksToScale) { … }

/// Pop up a ghostview window with the current block frequency propagation
/// rendered using dot.
void BlockFrequencyInfo::view(StringRef title) const { … }

const Function *BlockFrequencyInfo::getFunction() const { … }

const BranchProbabilityInfo *BlockFrequencyInfo::getBPI() const { … }

BlockFrequency BlockFrequencyInfo::getEntryFreq() const { … }

void BlockFrequencyInfo::releaseMemory() { … }

void BlockFrequencyInfo::print(raw_ostream &OS) const { … }

void BlockFrequencyInfo::verifyMatch(BlockFrequencyInfo &Other) const { … }

Printable llvm::printBlockFreq(const BlockFrequencyInfo &BFI,
                               BlockFrequency Freq) { … }

Printable llvm::printBlockFreq(const BlockFrequencyInfo &BFI,
                               const BasicBlock &BB) { … }

INITIALIZE_PASS_BEGIN(BlockFrequencyInfoWrapperPass, "block-freq",
                      "Block Frequency Analysis", true, true)
INITIALIZE_PASS_DEPENDENCY(BranchProbabilityInfoWrapperPass)
INITIALIZE_PASS_DEPENDENCY(LoopInfoWrapperPass)
INITIALIZE_PASS_END(BlockFrequencyInfoWrapperPass, "block-freq",
                    "Block Frequency Analysis", true, true)

char BlockFrequencyInfoWrapperPass::ID = …;

BlockFrequencyInfoWrapperPass::BlockFrequencyInfoWrapperPass()
    : … { … }

BlockFrequencyInfoWrapperPass::~BlockFrequencyInfoWrapperPass() = default;

void BlockFrequencyInfoWrapperPass::print(raw_ostream &OS,
                                          const Module *) const { … }

void BlockFrequencyInfoWrapperPass::getAnalysisUsage(AnalysisUsage &AU) const { … }

void BlockFrequencyInfoWrapperPass::releaseMemory() { … }

bool BlockFrequencyInfoWrapperPass::runOnFunction(Function &F) { … }

AnalysisKey BlockFrequencyAnalysis::Key;
BlockFrequencyInfo BlockFrequencyAnalysis::run(Function &F,
                                               FunctionAnalysisManager &AM) { … }

PreservedAnalyses
BlockFrequencyPrinterPass::run(Function &F, FunctionAnalysisManager &AM) { … }
llvm/llvm/lib/Analysis/BlockFrequencyInfo.cpp
