llvm/llvm/lib/CodeGen/GlobalISel/Legalizer.cpp

//===-- llvm/CodeGen/GlobalISel/Legalizer.cpp -----------------------------===//
//
// 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
//
//===----------------------------------------------------------------------===//
//
/// \file This file implements the LegalizerHelper class to legalize individual
/// instructions and the LegalizePass wrapper pass for the primary
/// legalization.
//
//===----------------------------------------------------------------------===//

#include "llvm/CodeGen/GlobalISel/Legalizer.h"
#include "llvm/ADT/PostOrderIterator.h"
#include "llvm/Analysis/OptimizationRemarkEmitter.h"
#include "llvm/CodeGen/GlobalISel/CSEInfo.h"
#include "llvm/CodeGen/GlobalISel/CSEMIRBuilder.h"
#include "llvm/CodeGen/GlobalISel/GISelChangeObserver.h"
#include "llvm/CodeGen/GlobalISel/GISelKnownBits.h"
#include "llvm/CodeGen/GlobalISel/GISelWorkList.h"
#include "llvm/CodeGen/GlobalISel/LegalizationArtifactCombiner.h"
#include "llvm/CodeGen/GlobalISel/LegalizerHelper.h"
#include "llvm/CodeGen/GlobalISel/LostDebugLocObserver.h"
#include "llvm/CodeGen/GlobalISel/Utils.h"
#include "llvm/CodeGen/MachineOptimizationRemarkEmitter.h"
#include "llvm/CodeGen/TargetPassConfig.h"
#include "llvm/CodeGen/TargetSubtargetInfo.h"
#include "llvm/InitializePasses.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/Error.h"

#define DEBUG_TYPE …

usingnamespacellvm;

static cl::opt<bool>
    EnableCSEInLegalizer("enable-cse-in-legalizer",
                         cl::desc("Should enable CSE in Legalizer"),
                         cl::Optional, cl::init(false));

// This is a temporary hack, should be removed soon.
static cl::opt<bool> AllowGInsertAsArtifact(
    "allow-ginsert-as-artifact",
    cl::desc("Allow G_INSERT to be considered an artifact. Hack around AMDGPU "
             "test infinite loops."),
    cl::Optional, cl::init(true));

enum class DebugLocVerifyLevel { … };
#ifndef NDEBUG
static cl::opt<DebugLocVerifyLevel> VerifyDebugLocs(
    "verify-legalizer-debug-locs",
    cl::desc("Verify that debug locations are handled"),
    cl::values(
        clEnumValN(DebugLocVerifyLevel::None, "none", "No verification"),
        clEnumValN(DebugLocVerifyLevel::Legalizations, "legalizations",
                   "Verify legalizations"),
        clEnumValN(DebugLocVerifyLevel::LegalizationsAndArtifactCombiners,
                   "legalizations+artifactcombiners",
                   "Verify legalizations and artifact combines")),
    cl::init(DebugLocVerifyLevel::Legalizations));
#else
// Always disable it for release builds by preventing the observer from being
// installed.
static const DebugLocVerifyLevel VerifyDebugLocs = …;
#endif

char Legalizer::ID = …;
INITIALIZE_PASS_BEGIN(Legalizer, DEBUG_TYPE,
                      "Legalize the Machine IR a function's Machine IR", false,
                      false)
INITIALIZE_PASS_DEPENDENCY(TargetPassConfig)
INITIALIZE_PASS_DEPENDENCY(GISelCSEAnalysisWrapperPass)
INITIALIZE_PASS_DEPENDENCY(GISelKnownBitsAnalysis)
INITIALIZE_PASS_END(Legalizer, DEBUG_TYPE,
                    "Legalize the Machine IR a function's Machine IR", false,
                    false)

Legalizer::Legalizer() : … { … }

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

void Legalizer::init(MachineFunction &MF) { … }

static bool isArtifact(const MachineInstr &MI) { … }
InstListTy;
ArtifactListTy;

namespace {
class LegalizerWorkListManager : public GISelChangeObserver { … };
} // namespace

Legalizer::MFResult
Legalizer::legalizeMachineFunction(MachineFunction &MF, const LegalizerInfo &LI,
                                   ArrayRef<GISelChangeObserver *> AuxObservers,
                                   LostDebugLocObserver &LocObserver,
                                   MachineIRBuilder &MIRBuilder,
                                   GISelKnownBits *KB) { … }

bool Legalizer::runOnMachineFunction(MachineFunction &MF) { … }