319 lines · cpp
1//===------ MacroFusionPredicatorEmitter.cpp - Generator for Fusion ------===//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// MacroFusionPredicatorEmitter implements a TableGen-driven predicators10// generator for macro-op fusions.11//12// This TableGen backend processes `Fusion` definitions and generates13// predicators for checking if input instructions can be fused. These14// predicators can used in `MacroFusion` DAG mutation.15//16// The generated header file contains two parts: one for predicator17// declarations and one for predicator implementations. The user can get them18// by defining macro `GET_<TargetName>_MACRO_FUSION_PRED_DECL` or19// `GET_<TargetName>_MACRO_FUSION_PRED_IMPL` and then including the generated20// header file.21//22// The generated predicator will be like:23//24// ```25// bool isNAME(const TargetInstrInfo &TII,26// const TargetSubtargetInfo &STI,27// const MachineInstr *FirstMI,28// const MachineInstr &SecondMI) {29// auto &MRI = SecondMI.getMF()->getRegInfo();30// /* Predicates */31// return true;32// }33// ```34//35// The `Predicates` part is generated from a list of `FusionPredicate`, which36// can be predefined predicates, a raw code string or `MCInstPredicate` defined37// in TargetInstrPredicate.td.38//39//===---------------------------------------------------------------------===//40 41#include "Common/CodeGenTarget.h"42#include "Common/PredicateExpander.h"43#include "llvm/Support/Debug.h"44#include "llvm/TableGen/Error.h"45#include "llvm/TableGen/Record.h"46#include "llvm/TableGen/TableGenBackend.h"47#include <vector>48 49using namespace llvm;50 51#define DEBUG_TYPE "macro-fusion-predicator"52 53namespace {54class MacroFusionPredicatorEmitter {55 const RecordKeeper &Records;56 const CodeGenTarget Target;57 58 void emitMacroFusionDecl(ArrayRef<const Record *> Fusions,59 PredicateExpander &PE, raw_ostream &OS);60 void emitMacroFusionImpl(ArrayRef<const Record *> Fusions,61 PredicateExpander &PE, raw_ostream &OS);62 void emitPredicates(ArrayRef<const Record *> FirstPredicate,63 bool IsCommutable, PredicateExpander &PE,64 raw_ostream &OS);65 void emitFirstPredicate(const Record *SecondPredicate, bool IsCommutable,66 PredicateExpander &PE, raw_ostream &OS);67 void emitSecondPredicate(const Record *SecondPredicate, bool IsCommutable,68 PredicateExpander &PE, raw_ostream &OS);69 void emitBothPredicate(const Record *Predicates, bool IsCommutable,70 PredicateExpander &PE, raw_ostream &OS);71 72public:73 MacroFusionPredicatorEmitter(const RecordKeeper &R) : Records(R), Target(R) {}74 75 void run(raw_ostream &OS);76};77} // End anonymous namespace.78 79void MacroFusionPredicatorEmitter::emitMacroFusionDecl(80 ArrayRef<const Record *> Fusions, PredicateExpander &PE, raw_ostream &OS) {81 OS << "#ifdef GET_" << Target.getName() << "_MACRO_FUSION_PRED_DECL\n";82 OS << "#undef GET_" << Target.getName() << "_MACRO_FUSION_PRED_DECL\n\n";83 OS << "namespace llvm {\n";84 85 for (const Record *Fusion : Fusions) {86 OS << "bool is" << Fusion->getName() << "(const TargetInstrInfo &, "87 << "const TargetSubtargetInfo &, "88 << "const MachineInstr *, "89 << "const MachineInstr &);\n";90 }91 92 OS << "} // end namespace llvm\n";93 OS << "\n#endif\n";94}95 96void MacroFusionPredicatorEmitter::emitMacroFusionImpl(97 ArrayRef<const Record *> Fusions, PredicateExpander &PE, raw_ostream &OS) {98 OS << "#ifdef GET_" << Target.getName() << "_MACRO_FUSION_PRED_IMPL\n";99 OS << "#undef GET_" << Target.getName() << "_MACRO_FUSION_PRED_IMPL\n\n";100 OS << "namespace llvm {\n";101 102 for (const Record *Fusion : Fusions) {103 std::vector<const Record *> Predicates =104 Fusion->getValueAsListOfDefs("Predicates");105 bool IsCommutable = Fusion->getValueAsBit("IsCommutable");106 107 OS << "bool is" << Fusion->getName() << "(\n";108 OS.indent(4) << "const TargetInstrInfo &TII,\n";109 OS.indent(4) << "const TargetSubtargetInfo &STI,\n";110 OS.indent(4) << "const MachineInstr *FirstMI,\n";111 OS.indent(4) << "const MachineInstr &SecondMI) {\n";112 OS.indent(2)113 << "[[maybe_unused]] auto &MRI = SecondMI.getMF()->getRegInfo();\n";114 115 emitPredicates(Predicates, IsCommutable, PE, OS);116 117 OS.indent(2) << "return true;\n";118 OS << "}\n";119 }120 121 OS << "} // end namespace llvm\n";122 OS << "\n#endif\n";123}124 125void MacroFusionPredicatorEmitter::emitPredicates(126 ArrayRef<const Record *> Predicates, bool IsCommutable,127 PredicateExpander &PE, raw_ostream &OS) {128 for (const Record *Predicate : Predicates) {129 const Record *Target = Predicate->getValueAsDef("Target");130 if (Target->getName() == "first_fusion_target")131 emitFirstPredicate(Predicate, IsCommutable, PE, OS);132 else if (Target->getName() == "second_fusion_target")133 emitSecondPredicate(Predicate, IsCommutable, PE, OS);134 else if (Target->getName() == "both_fusion_target")135 emitBothPredicate(Predicate, IsCommutable, PE, OS);136 else137 PrintFatalError(Target->getLoc(),138 "Unsupported 'FusionTarget': " + Target->getName());139 }140}141 142void MacroFusionPredicatorEmitter::emitFirstPredicate(const Record *Predicate,143 bool IsCommutable,144 PredicateExpander &PE,145 raw_ostream &OS) {146 if (Predicate->isSubClassOf("WildcardPred")) {147 OS.indent(2) << "if (!FirstMI)\n";148 OS.indent(2) << " return "149 << (Predicate->getValueAsBit("ReturnValue") ? "true" : "false")150 << ";\n";151 } else if (Predicate->isSubClassOf("OneUsePred")) {152 OS.indent(2) << "{\n";153 OS.indent(4) << "Register FirstDest = FirstMI->getOperand(0).getReg();\n";154 OS.indent(4)155 << "if (FirstDest.isVirtual() && !MRI.hasOneNonDBGUse(FirstDest))\n";156 OS.indent(4) << " return false;\n";157 OS.indent(2) << "}\n";158 } else if (Predicate->isSubClassOf("FirstInstHasSameReg")) {159 int FirstOpIdx = Predicate->getValueAsInt("FirstOpIdx");160 int SecondOpIdx = Predicate->getValueAsInt("SecondOpIdx");161 162 OS.indent(2) << "if (!FirstMI->getOperand(" << FirstOpIdx163 << ").getReg().isVirtual()) {\n";164 OS.indent(4) << "if (FirstMI->getOperand(" << FirstOpIdx165 << ").getReg() != FirstMI->getOperand(" << SecondOpIdx166 << ").getReg())";167 168 if (IsCommutable) {169 OS << " {\n";170 OS.indent(6) << "if (!FirstMI->getDesc().isCommutable())\n";171 OS.indent(6) << " return false;\n";172 173 OS.indent(6)174 << "unsigned SrcOpIdx1 = " << SecondOpIdx175 << ", SrcOpIdx2 = TargetInstrInfo::CommuteAnyOperandIndex;\n";176 OS.indent(6)177 << "if (TII.findCommutedOpIndices(FirstMI, SrcOpIdx1, SrcOpIdx2))\n";178 OS.indent(6)179 << " if (FirstMI->getOperand(" << FirstOpIdx180 << ").getReg() != FirstMI->getOperand(SrcOpIdx2).getReg())\n";181 OS.indent(6) << " return false;\n";182 OS.indent(4) << "}\n";183 } else {184 OS << "\n";185 OS.indent(4) << " return false;\n";186 }187 OS.indent(2) << "}\n";188 } else if (Predicate->isSubClassOf("FusionPredicateWithMCInstPredicate")) {189 OS.indent(2) << "{\n";190 OS.indent(4) << "const MachineInstr *MI = FirstMI;\n";191 OS.indent(4) << "if (";192 PE.setNegatePredicate(true);193 PE.getIndent() = 3;194 PE.expandPredicate(OS, Predicate->getValueAsDef("Predicate"));195 OS << ")\n";196 OS.indent(4) << " return false;\n";197 OS.indent(2) << "}\n";198 } else {199 PrintFatalError(Predicate->getLoc(),200 "Unsupported predicate for first instruction: " +201 Predicate->getType()->getAsString());202 }203}204 205void MacroFusionPredicatorEmitter::emitSecondPredicate(const Record *Predicate,206 bool IsCommutable,207 PredicateExpander &PE,208 raw_ostream &OS) {209 if (Predicate->isSubClassOf("FusionPredicateWithMCInstPredicate")) {210 OS.indent(2) << "{\n";211 OS.indent(4) << "const MachineInstr *MI = &SecondMI;\n";212 OS.indent(4) << "if (";213 PE.setNegatePredicate(true);214 PE.getIndent() = 3;215 PE.expandPredicate(OS, Predicate->getValueAsDef("Predicate"));216 OS << ")\n";217 OS.indent(4) << " return false;\n";218 OS.indent(2) << "}\n";219 } else if (Predicate->isSubClassOf("SecondInstHasSameReg")) {220 int FirstOpIdx = Predicate->getValueAsInt("FirstOpIdx");221 int SecondOpIdx = Predicate->getValueAsInt("SecondOpIdx");222 223 OS.indent(2) << "if (!SecondMI.getOperand(" << FirstOpIdx224 << ").getReg().isVirtual()) {\n";225 OS.indent(4) << "if (SecondMI.getOperand(" << FirstOpIdx226 << ").getReg() != SecondMI.getOperand(" << SecondOpIdx227 << ").getReg())";228 229 if (IsCommutable) {230 OS << " {\n";231 OS.indent(6) << "if (!SecondMI.getDesc().isCommutable())\n";232 OS.indent(6) << " return false;\n";233 234 OS.indent(6)235 << "unsigned SrcOpIdx1 = " << SecondOpIdx236 << ", SrcOpIdx2 = TargetInstrInfo::CommuteAnyOperandIndex;\n";237 OS.indent(6)238 << "if (TII.findCommutedOpIndices(SecondMI, SrcOpIdx1, SrcOpIdx2))\n";239 OS.indent(6)240 << " if (SecondMI.getOperand(" << FirstOpIdx241 << ").getReg() != SecondMI.getOperand(SrcOpIdx2).getReg())\n";242 OS.indent(6) << " return false;\n";243 OS.indent(4) << "}\n";244 } else {245 OS << "\n";246 OS.indent(4) << " return false;\n";247 }248 OS.indent(2) << "}\n";249 } else {250 PrintFatalError(Predicate->getLoc(),251 "Unsupported predicate for second instruction: " +252 Predicate->getType()->getAsString());253 }254}255 256void MacroFusionPredicatorEmitter::emitBothPredicate(const Record *Predicate,257 bool IsCommutable,258 PredicateExpander &PE,259 raw_ostream &OS) {260 if (Predicate->isSubClassOf("FusionPredicateWithCode"))261 OS << Predicate->getValueAsString("Predicate");262 else if (Predicate->isSubClassOf("BothFusionPredicateWithMCInstPredicate")) {263 emitFirstPredicate(Predicate, IsCommutable, PE, OS);264 emitSecondPredicate(Predicate, IsCommutable, PE, OS);265 } else if (Predicate->isSubClassOf("TieReg")) {266 int FirstOpIdx = Predicate->getValueAsInt("FirstOpIdx");267 int SecondOpIdx = Predicate->getValueAsInt("SecondOpIdx");268 OS.indent(2) << "if (!(FirstMI->getOperand(" << FirstOpIdx269 << ").isReg() &&\n";270 OS.indent(2) << " SecondMI.getOperand(" << SecondOpIdx271 << ").isReg() &&\n";272 OS.indent(2) << " FirstMI->getOperand(" << FirstOpIdx273 << ").getReg() == SecondMI.getOperand(" << SecondOpIdx274 << ").getReg()))";275 276 if (IsCommutable) {277 OS << " {\n";278 OS.indent(4) << "if (!SecondMI.getDesc().isCommutable())\n";279 OS.indent(4) << " return false;\n";280 281 OS.indent(4)282 << "unsigned SrcOpIdx1 = " << SecondOpIdx283 << ", SrcOpIdx2 = TargetInstrInfo::CommuteAnyOperandIndex;\n";284 OS.indent(4)285 << "if (TII.findCommutedOpIndices(SecondMI, SrcOpIdx1, SrcOpIdx2))\n";286 OS.indent(4)287 << " if (FirstMI->getOperand(" << FirstOpIdx288 << ").getReg() != SecondMI.getOperand(SrcOpIdx2).getReg())\n";289 OS.indent(4) << " return false;\n";290 OS.indent(2) << "}";291 } else {292 OS << "\n";293 OS.indent(2) << " return false;";294 }295 OS << "\n";296 } else {297 PrintFatalError(Predicate->getLoc(),298 "Unsupported predicate for both instruction: " +299 Predicate->getType()->getAsString());300 }301}302 303void MacroFusionPredicatorEmitter::run(raw_ostream &OS) {304 // Emit file header.305 emitSourceFileHeader("Macro Fusion Predicators", OS);306 307 PredicateExpander PE(Target.getName());308 PE.setByRef(false);309 PE.setExpandForMC(false);310 311 ArrayRef<const Record *> Fusions = Records.getAllDerivedDefinitions("Fusion");312 emitMacroFusionDecl(Fusions, PE, OS);313 OS << "\n";314 emitMacroFusionImpl(Fusions, PE, OS);315}316 317static TableGen::Emitter::OptClass<MacroFusionPredicatorEmitter>318 X("gen-macro-fusion-pred", "Generate macro fusion predicators.");319