171 lines · cpp
1//=== RISCVPreLegalizerCombiner.cpp ---------------------------------------===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8//9// This pass does combining of machine instructions at the generic MI level,10// before the legalizer.11//12//===----------------------------------------------------------------------===//13 14#include "RISCVSubtarget.h"15#include "llvm/CodeGen/GlobalISel/CSEInfo.h"16#include "llvm/CodeGen/GlobalISel/Combiner.h"17#include "llvm/CodeGen/GlobalISel/CombinerHelper.h"18#include "llvm/CodeGen/GlobalISel/CombinerInfo.h"19#include "llvm/CodeGen/GlobalISel/GIMatchTableExecutorImpl.h"20#include "llvm/CodeGen/GlobalISel/GISelValueTracking.h"21#include "llvm/CodeGen/GlobalISel/MachineIRBuilder.h"22#include "llvm/CodeGen/MachineDominators.h"23#include "llvm/CodeGen/MachineFunction.h"24#include "llvm/CodeGen/MachineFunctionPass.h"25#include "llvm/CodeGen/TargetPassConfig.h"26 27#define GET_GICOMBINER_DEPS28#include "RISCVGenPreLegalizeGICombiner.inc"29#undef GET_GICOMBINER_DEPS30 31#define DEBUG_TYPE "riscv-prelegalizer-combiner"32 33using namespace llvm;34 35namespace {36 37#define GET_GICOMBINER_TYPES38#include "RISCVGenPreLegalizeGICombiner.inc"39#undef GET_GICOMBINER_TYPES40 41class RISCVPreLegalizerCombinerImpl : public Combiner {42protected:43 const CombinerHelper Helper;44 const RISCVPreLegalizerCombinerImplRuleConfig &RuleConfig;45 const RISCVSubtarget &STI;46 47public:48 RISCVPreLegalizerCombinerImpl(49 MachineFunction &MF, CombinerInfo &CInfo, const TargetPassConfig *TPC,50 GISelValueTracking &VT, GISelCSEInfo *CSEInfo,51 const RISCVPreLegalizerCombinerImplRuleConfig &RuleConfig,52 const RISCVSubtarget &STI, MachineDominatorTree *MDT,53 const LegalizerInfo *LI);54 55 static const char *getName() { return "RISCV00PreLegalizerCombiner"; }56 57 bool tryCombineAll(MachineInstr &I) const override;58 59private:60#define GET_GICOMBINER_CLASS_MEMBERS61#include "RISCVGenPreLegalizeGICombiner.inc"62#undef GET_GICOMBINER_CLASS_MEMBERS63};64 65#define GET_GICOMBINER_IMPL66#include "RISCVGenPreLegalizeGICombiner.inc"67#undef GET_GICOMBINER_IMPL68 69RISCVPreLegalizerCombinerImpl::RISCVPreLegalizerCombinerImpl(70 MachineFunction &MF, CombinerInfo &CInfo, const TargetPassConfig *TPC,71 GISelValueTracking &VT, GISelCSEInfo *CSEInfo,72 const RISCVPreLegalizerCombinerImplRuleConfig &RuleConfig,73 const RISCVSubtarget &STI, MachineDominatorTree *MDT,74 const LegalizerInfo *LI)75 : Combiner(MF, CInfo, TPC, &VT, CSEInfo),76 Helper(Observer, B, /*IsPreLegalize*/ true, &VT, MDT, LI),77 RuleConfig(RuleConfig), STI(STI),78#define GET_GICOMBINER_CONSTRUCTOR_INITS79#include "RISCVGenPreLegalizeGICombiner.inc"80#undef GET_GICOMBINER_CONSTRUCTOR_INITS81{82}83 84// Pass boilerplate85// ================86 87class RISCVPreLegalizerCombiner : public MachineFunctionPass {88public:89 static char ID;90 91 RISCVPreLegalizerCombiner();92 93 StringRef getPassName() const override { return "RISCVPreLegalizerCombiner"; }94 95 bool runOnMachineFunction(MachineFunction &MF) override;96 97 void getAnalysisUsage(AnalysisUsage &AU) const override;98 99private:100 RISCVPreLegalizerCombinerImplRuleConfig RuleConfig;101};102} // end anonymous namespace103 104void RISCVPreLegalizerCombiner::getAnalysisUsage(AnalysisUsage &AU) const {105 AU.addRequired<TargetPassConfig>();106 AU.setPreservesCFG();107 getSelectionDAGFallbackAnalysisUsage(AU);108 AU.addRequired<GISelValueTrackingAnalysisLegacy>();109 AU.addPreserved<GISelValueTrackingAnalysisLegacy>();110 AU.addRequired<MachineDominatorTreeWrapperPass>();111 AU.addPreserved<MachineDominatorTreeWrapperPass>();112 AU.addRequired<GISelCSEAnalysisWrapperPass>();113 AU.addPreserved<GISelCSEAnalysisWrapperPass>();114 MachineFunctionPass::getAnalysisUsage(AU);115}116 117RISCVPreLegalizerCombiner::RISCVPreLegalizerCombiner()118 : MachineFunctionPass(ID) {119 if (!RuleConfig.parseCommandLineOption())120 report_fatal_error("Invalid rule identifier");121}122 123bool RISCVPreLegalizerCombiner::runOnMachineFunction(MachineFunction &MF) {124 if (MF.getProperties().hasFailedISel())125 return false;126 auto &TPC = getAnalysis<TargetPassConfig>();127 128 // Enable CSE.129 GISelCSEAnalysisWrapper &Wrapper =130 getAnalysis<GISelCSEAnalysisWrapperPass>().getCSEWrapper();131 auto *CSEInfo = &Wrapper.get(TPC.getCSEConfig());132 133 const RISCVSubtarget &ST = MF.getSubtarget<RISCVSubtarget>();134 const auto *LI = ST.getLegalizerInfo();135 136 const Function &F = MF.getFunction();137 bool EnableOpt =138 MF.getTarget().getOptLevel() != CodeGenOptLevel::None && !skipFunction(F);139 GISelValueTracking *VT =140 &getAnalysis<GISelValueTrackingAnalysisLegacy>().get(MF);141 MachineDominatorTree *MDT =142 &getAnalysis<MachineDominatorTreeWrapperPass>().getDomTree();143 CombinerInfo CInfo(/*AllowIllegalOps*/ true, /*ShouldLegalizeIllegal*/ false,144 /*LegalizerInfo*/ nullptr, EnableOpt, F.hasOptSize(),145 F.hasMinSize());146 // Disable fixed-point iteration to reduce compile-time147 CInfo.MaxIterations = 1;148 CInfo.ObserverLvl = CombinerInfo::ObserverLevel::SinglePass;149 // This is the first Combiner, so the input IR might contain dead150 // instructions.151 CInfo.EnableFullDCE = true;152 RISCVPreLegalizerCombinerImpl Impl(MF, CInfo, &TPC, *VT, CSEInfo, RuleConfig,153 ST, MDT, LI);154 return Impl.combineMachineInstrs();155}156 157char RISCVPreLegalizerCombiner::ID = 0;158INITIALIZE_PASS_BEGIN(RISCVPreLegalizerCombiner, DEBUG_TYPE,159 "Combine RISC-V machine instrs before legalization", false,160 false)161INITIALIZE_PASS_DEPENDENCY(TargetPassConfig)162INITIALIZE_PASS_DEPENDENCY(GISelValueTrackingAnalysisLegacy)163INITIALIZE_PASS_DEPENDENCY(GISelCSEAnalysisWrapperPass)164INITIALIZE_PASS_END(RISCVPreLegalizerCombiner, DEBUG_TYPE,165 "Combine RISC-V machine instrs before legalization", false,166 false)167 168FunctionPass *llvm::createRISCVPreLegalizerCombiner() {169 return new RISCVPreLegalizerCombiner();170}171