llvm/llvm/lib/CodeGen/MachineBlockFrequencyInfo.cpp

//===- MachineBlockFrequencyInfo.cpp - MBB 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/CodeGen/MachineBlockFrequencyInfo.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/iterator.h"
#include "llvm/Analysis/BlockFrequencyInfoImpl.h"
#include "llvm/CodeGen/MachineBasicBlock.h"
#include "llvm/CodeGen/MachineBranchProbabilityInfo.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/MachineLoopInfo.h"
#include "llvm/InitializePasses.h"
#include "llvm/Pass.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/GraphWriter.h"
#include <optional>
#include <string>

usingnamespacellvm;

#define DEBUG_TYPE …

namespace llvm {
static cl::opt<GVDAGType> ViewMachineBlockFreqPropagationDAG(
    "view-machine-block-freq-propagation-dags", cl::Hidden,
    cl::desc("Pop up a window to show a dag displaying how machine block "
             "frequencies propagate 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.")));

// Similar option above, but used to control BFI display only after MBP pass
cl::opt<GVDAGType> ViewBlockLayoutWithBFI(
    "view-block-layout-with-bfi", cl::Hidden,
    cl::desc(
        "Pop up a window to show a dag displaying MBP layout and associated "
        "block frequencies of 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.")));

// Command line option to specify the name of the function for CFG dump
// Defined in Analysis/BlockFrequencyInfo.cpp:  -view-bfi-func-name=
extern cl::opt<std::string> ViewBlockFreqFuncName;

// Command line option to specify hot frequency threshold.
// Defined in Analysis/BlockFrequencyInfo.cpp:  -view-hot-freq-perc=
extern cl::opt<unsigned> ViewHotFreqPercent;

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

// Command line option to specify the name of the function for block frequency
// dump. Defined in Analysis/BlockFrequencyInfo.cpp.
extern cl::opt<std::string> PrintBFIFuncName;
} // namespace llvm

static GVDAGType getGVDT() { … }

namespace llvm {

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

MBFIDOTGraphTraitsBase;

template <>
struct DOTGraphTraits<MachineBlockFrequencyInfo *>
    : public MBFIDOTGraphTraitsBase { … };

} // end namespace llvm

AnalysisKey MachineBlockFrequencyAnalysis::Key;

MachineBlockFrequencyAnalysis::Result
MachineBlockFrequencyAnalysis::run(MachineFunction &MF,
                                   MachineFunctionAnalysisManager &MFAM) { … }

PreservedAnalyses
MachineBlockFrequencyPrinterPass::run(MachineFunction &MF,
                                      MachineFunctionAnalysisManager &MFAM) { … }

INITIALIZE_PASS_BEGIN(MachineBlockFrequencyInfoWrapperPass, DEBUG_TYPE,
                      "Machine Block Frequency Analysis", true, true)
INITIALIZE_PASS_DEPENDENCY(MachineBranchProbabilityInfoWrapperPass)
INITIALIZE_PASS_DEPENDENCY(MachineLoopInfoWrapperPass)
INITIALIZE_PASS_END(MachineBlockFrequencyInfoWrapperPass, DEBUG_TYPE,
                    "Machine Block Frequency Analysis", true, true)

char MachineBlockFrequencyInfoWrapperPass::ID = …;

MachineBlockFrequencyInfoWrapperPass::MachineBlockFrequencyInfoWrapperPass()
    : … { … }

MachineBlockFrequencyInfo::MachineBlockFrequencyInfo() = default;

MachineBlockFrequencyInfo::MachineBlockFrequencyInfo(
    MachineBlockFrequencyInfo &&) = default;

MachineBlockFrequencyInfo::MachineBlockFrequencyInfo(
    MachineFunction &F, MachineBranchProbabilityInfo &MBPI,
    MachineLoopInfo &MLI) { … }

MachineBlockFrequencyInfo::~MachineBlockFrequencyInfo() = default;

bool MachineBlockFrequencyInfo::invalidate(
    MachineFunction &MF, const PreservedAnalyses &PA,
    MachineFunctionAnalysisManager::Invalidator &) { … }

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

void MachineBlockFrequencyInfo::calculate(
    const MachineFunction &F, const MachineBranchProbabilityInfo &MBPI,
    const MachineLoopInfo &MLI) { … }

bool MachineBlockFrequencyInfoWrapperPass::runOnMachineFunction(
    MachineFunction &F) { … }

void MachineBlockFrequencyInfo::print(raw_ostream &OS) { … }

void MachineBlockFrequencyInfo::releaseMemory() { … }

/// Pop up a ghostview window with the current block frequency propagation
/// rendered using dot.
void MachineBlockFrequencyInfo::view(const Twine &Name, bool isSimple) const { … }

BlockFrequency
MachineBlockFrequencyInfo::getBlockFreq(const MachineBasicBlock *MBB) const { … }

std::optional<uint64_t> MachineBlockFrequencyInfo::getBlockProfileCount(
    const MachineBasicBlock *MBB) const { … }

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

bool MachineBlockFrequencyInfo::isIrrLoopHeader(
    const MachineBasicBlock *MBB) const { … }

void MachineBlockFrequencyInfo::onEdgeSplit(
    const MachineBasicBlock &NewPredecessor,
    const MachineBasicBlock &NewSuccessor,
    const MachineBranchProbabilityInfo &MBPI) { … }

const MachineFunction *MachineBlockFrequencyInfo::getFunction() const { … }

const MachineBranchProbabilityInfo *MachineBlockFrequencyInfo::getMBPI() const { … }

BlockFrequency MachineBlockFrequencyInfo::getEntryFreq() const { … }

Printable llvm::printBlockFreq(const MachineBlockFrequencyInfo &MBFI,
                               BlockFrequency Freq) { … }

Printable llvm::printBlockFreq(const MachineBlockFrequencyInfo &MBFI,
                               const MachineBasicBlock &MBB) { … }