1 //=== RISCVO0PreLegalizerCombiner.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-exception 6 // 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/Combiner.h" 16 #include "llvm/CodeGen/GlobalISel/CombinerHelper.h" 17 #include "llvm/CodeGen/GlobalISel/CombinerInfo.h" 18 #include "llvm/CodeGen/GlobalISel/GIMatchTableExecutorImpl.h" 19 #include "llvm/CodeGen/GlobalISel/GISelKnownBits.h" 20 #include "llvm/CodeGen/GlobalISel/MachineIRBuilder.h" 21 #include "llvm/CodeGen/MachineDominators.h" 22 #include "llvm/CodeGen/MachineFunction.h" 23 #include "llvm/CodeGen/MachineFunctionPass.h" 24 #include "llvm/CodeGen/TargetPassConfig.h" 25 26 #define GET_GICOMBINER_DEPS 27 #include "RISCVGenO0PreLegalizeGICombiner.inc" 28 #undef GET_GICOMBINER_DEPS 29 30 #define DEBUG_TYPE "riscv-O0-prelegalizer-combiner" 31 32 using namespace llvm; 33 34 namespace { 35 #define GET_GICOMBINER_TYPES 36 #include "RISCVGenO0PreLegalizeGICombiner.inc" 37 #undef GET_GICOMBINER_TYPES 38 39 class RISCVO0PreLegalizerCombinerImpl : public Combiner { 40 protected: 41 const CombinerHelper Helper; 42 const RISCVO0PreLegalizerCombinerImplRuleConfig &RuleConfig; 43 const RISCVSubtarget &STI; 44 45 public: 46 RISCVO0PreLegalizerCombinerImpl( 47 MachineFunction &MF, CombinerInfo &CInfo, const TargetPassConfig *TPC, 48 GISelKnownBits &KB, GISelCSEInfo *CSEInfo, 49 const RISCVO0PreLegalizerCombinerImplRuleConfig &RuleConfig, 50 const RISCVSubtarget &STI); 51 52 static const char *getName() { return "RISCVO0PreLegalizerCombiner"; } 53 54 bool tryCombineAll(MachineInstr &I) const override; 55 56 private: 57 #define GET_GICOMBINER_CLASS_MEMBERS 58 #include "RISCVGenO0PreLegalizeGICombiner.inc" 59 #undef GET_GICOMBINER_CLASS_MEMBERS 60 }; 61 62 #define GET_GICOMBINER_IMPL 63 #include "RISCVGenO0PreLegalizeGICombiner.inc" 64 #undef GET_GICOMBINER_IMPL 65 66 RISCVO0PreLegalizerCombinerImpl::RISCVO0PreLegalizerCombinerImpl( 67 MachineFunction &MF, CombinerInfo &CInfo, const TargetPassConfig *TPC, 68 GISelKnownBits &KB, GISelCSEInfo *CSEInfo, 69 const RISCVO0PreLegalizerCombinerImplRuleConfig &RuleConfig, 70 const RISCVSubtarget &STI) 71 : Combiner(MF, CInfo, TPC, &KB, CSEInfo), 72 Helper(Observer, B, /*IsPreLegalize*/ true, &KB), RuleConfig(RuleConfig), 73 STI(STI), 74 #define GET_GICOMBINER_CONSTRUCTOR_INITS 75 #include "RISCVGenO0PreLegalizeGICombiner.inc" 76 #undef GET_GICOMBINER_CONSTRUCTOR_INITS 77 { 78 } 79 80 // Pass boilerplate 81 // ================ 82 83 class RISCVO0PreLegalizerCombiner : public MachineFunctionPass { 84 public: 85 static char ID; 86 87 RISCVO0PreLegalizerCombiner(); 88 89 StringRef getPassName() const override { 90 return "RISCVO0PreLegalizerCombiner"; 91 } 92 93 bool runOnMachineFunction(MachineFunction &MF) override; 94 95 void getAnalysisUsage(AnalysisUsage &AU) const override; 96 97 private: 98 RISCVO0PreLegalizerCombinerImplRuleConfig RuleConfig; 99 }; 100 } // end anonymous namespace 101 102 void RISCVO0PreLegalizerCombiner::getAnalysisUsage(AnalysisUsage &AU) const { 103 AU.addRequired<TargetPassConfig>(); 104 AU.setPreservesCFG(); 105 getSelectionDAGFallbackAnalysisUsage(AU); 106 AU.addRequired<GISelKnownBitsAnalysis>(); 107 AU.addPreserved<GISelKnownBitsAnalysis>(); 108 MachineFunctionPass::getAnalysisUsage(AU); 109 } 110 111 RISCVO0PreLegalizerCombiner::RISCVO0PreLegalizerCombiner() 112 : MachineFunctionPass(ID) { 113 initializeRISCVO0PreLegalizerCombinerPass(*PassRegistry::getPassRegistry()); 114 115 if (!RuleConfig.parseCommandLineOption()) 116 report_fatal_error("Invalid rule identifier"); 117 } 118 119 bool RISCVO0PreLegalizerCombiner::runOnMachineFunction(MachineFunction &MF) { 120 if (MF.getProperties().hasProperty( 121 MachineFunctionProperties::Property::FailedISel)) 122 return false; 123 auto &TPC = getAnalysis<TargetPassConfig>(); 124 125 const Function &F = MF.getFunction(); 126 GISelKnownBits *KB = &getAnalysis<GISelKnownBitsAnalysis>().get(MF); 127 128 const RISCVSubtarget &ST = MF.getSubtarget<RISCVSubtarget>(); 129 130 CombinerInfo CInfo(/*AllowIllegalOps*/ true, /*ShouldLegalizeIllegal*/ false, 131 /*LegalizerInfo*/ nullptr, /*EnableOpt*/ false, 132 F.hasOptSize(), F.hasMinSize()); 133 // Disable fixed-point iteration in the Combiner. This improves compile-time 134 // at the cost of possibly missing optimizations. See PR#94291 for details. 135 CInfo.MaxIterations = 1; 136 137 RISCVO0PreLegalizerCombinerImpl Impl(MF, CInfo, &TPC, *KB, 138 /*CSEInfo*/ nullptr, RuleConfig, ST); 139 return Impl.combineMachineInstrs(); 140 } 141 142 char RISCVO0PreLegalizerCombiner::ID = 0; 143 INITIALIZE_PASS_BEGIN(RISCVO0PreLegalizerCombiner, DEBUG_TYPE, 144 "Combine RISC-V machine instrs before legalization", 145 false, false) 146 INITIALIZE_PASS_DEPENDENCY(TargetPassConfig) 147 INITIALIZE_PASS_DEPENDENCY(GISelKnownBitsAnalysis) 148 INITIALIZE_PASS_DEPENDENCY(GISelCSEAnalysisWrapperPass) 149 INITIALIZE_PASS_END(RISCVO0PreLegalizerCombiner, DEBUG_TYPE, 150 "Combine RISC-V machine instrs before legalization", false, 151 false) 152 153 namespace llvm { 154 FunctionPass *createRISCVO0PreLegalizerCombiner() { 155 return new RISCVO0PreLegalizerCombiner(); 156 } 157 } // end namespace llvm 158