224 lines · cpp
1//===- SubtargetFeatureInfo.cpp - Helpers for subtarget features ----------===//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#include "SubtargetFeatureInfo.h"10#include "Types.h"11#include "llvm/Config/llvm-config.h"12#include "llvm/TableGen/Error.h"13#include "llvm/TableGen/Record.h"14 15using namespace llvm;16 17#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)18LLVM_DUMP_METHOD void SubtargetFeatureInfo::dump() const {19 errs() << getEnumName() << " " << Index << "\n" << *TheDef;20}21#endif22 23SubtargetFeaturesInfoVec24SubtargetFeatureInfo::getAll(const RecordKeeper &Records) {25 SubtargetFeaturesInfoVec SubtargetFeatures;26 for (const Record *Pred : Records.getAllDerivedDefinitions("Predicate")) {27 // Ignore predicates that are not intended for the assembler.28 //29 // The "AssemblerMatcherPredicate" string should be promoted to an argument30 // if we re-use the machinery for non-assembler purposes in future.31 if (!Pred->getValueAsBit("AssemblerMatcherPredicate"))32 continue;33 34 if (Pred->getName().empty())35 PrintFatalError(Pred->getLoc(), "Predicate has no name!");36 37 // Ignore always true predicates.38 if (Pred->getValueAsString("CondString").empty())39 continue;40 41 SubtargetFeatures.emplace_back(42 Pred, SubtargetFeatureInfo(Pred, SubtargetFeatures.size()));43 }44 return SubtargetFeatures;45}46 47void SubtargetFeatureInfo::emitSubtargetFeatureBitEnumeration(48 const SubtargetFeatureInfoMap &SubtargetFeatures, raw_ostream &OS,49 const std::map<std::string, unsigned> *HwModes) {50 OS << "// Bits for subtarget features that participate in "51 << "instruction matching.\n";52 unsigned Size = SubtargetFeatures.size();53 if (HwModes)54 Size += HwModes->size();55 56 OS << "enum SubtargetFeatureBits : " << getMinimalTypeForRange(Size)57 << " {\n";58 for (const auto &SF : SubtargetFeatures) {59 const SubtargetFeatureInfo &SFI = SF.second;60 OS << " " << SFI.getEnumBitName() << " = " << SFI.Index << ",\n";61 }62 63 if (HwModes) {64 unsigned Offset = SubtargetFeatures.size();65 for (const auto &M : *HwModes) {66 OS << " Feature_HwMode" << M.second << "Bit = " << (M.second + Offset)67 << ",\n";68 }69 }70 71 OS << "};\n\n";72}73 74void SubtargetFeatureInfo::emitNameTable(75 SubtargetFeatureInfoMap &SubtargetFeatures, raw_ostream &OS) {76 // Need to sort the name table so that lookup by the log of the enum value77 // gives the proper name. More specifically, for a feature of value 1<<n,78 // SubtargetFeatureNames[n] should be the name of the feature.79 uint64_t IndexUB = 0;80 for (const auto &SF : SubtargetFeatures)81 if (IndexUB <= SF.second.Index)82 IndexUB = SF.second.Index + 1;83 84 std::vector<std::string> Names;85 if (IndexUB > 0)86 Names.resize(IndexUB);87 for (const auto &SF : SubtargetFeatures)88 Names[SF.second.Index] = SF.second.getEnumName();89 90 OS << "static const char *SubtargetFeatureNames[] = {\n";91 for (uint64_t I = 0; I < IndexUB; ++I)92 OS << " \"" << Names[I] << "\",\n";93 94 // A small number of targets have no predicates. Null terminate the array to95 // avoid a zero-length array.96 OS << " nullptr\n"97 << "};\n\n";98}99 100void SubtargetFeatureInfo::emitComputeAvailableFeatures(101 StringRef TargetName, StringRef ClassName, StringRef FuncName,102 const SubtargetFeatureInfoMap &SubtargetFeatures, raw_ostream &OS,103 StringRef ExtraParams, const std::map<std::string, unsigned> *HwModes) {104 OS << "PredicateBitset " << ClassName << "::\n"105 << FuncName << "(const " << TargetName << "Subtarget *Subtarget";106 if (!ExtraParams.empty())107 OS << ", " << ExtraParams;108 OS << ") const {\n";109 OS << " PredicateBitset Features{};\n";110 for (const auto &SF : SubtargetFeatures) {111 const SubtargetFeatureInfo &SFI = SF.second;112 StringRef CondStr = SFI.TheDef->getValueAsString("CondString");113 assert(!CondStr.empty() && "true predicate should have been filtered");114 115 OS << " if (" << CondStr << ")\n";116 OS << " Features.set(" << SFI.getEnumBitName() << ");\n";117 }118 119 if (HwModes) {120 for (const auto &M : *HwModes) {121 OS << " if (" << M.first << ")\n";122 OS << " Features.set(Feature_HwMode" << M.second << "Bit);\n";123 }124 }125 126 OS << " return Features;\n";127 OS << "}\n\n";128}129 130// If ParenIfBinOp is true, print a surrounding () if Val uses && or ||.131static bool emitFeaturesAux(StringRef TargetName, const Init &Val,132 bool ParenIfBinOp, raw_ostream &OS) {133 if (auto *D = dyn_cast<DefInit>(&Val)) {134 if (!D->getDef()->isSubClassOf("SubtargetFeature"))135 return true;136 OS << "FB[" << TargetName << "::" << D->getAsString() << "]";137 return false;138 }139 if (auto *D = dyn_cast<DagInit>(&Val)) {140 auto *Op = dyn_cast<DefInit>(D->getOperator());141 if (!Op)142 return true;143 StringRef OpName = Op->getDef()->getName();144 if (OpName == "not" && D->getNumArgs() == 1) {145 OS << '!';146 return emitFeaturesAux(TargetName, *D->getArg(0), true, OS);147 }148 if ((OpName == "any_of" || OpName == "all_of") && D->getNumArgs() > 0) {149 bool Paren = D->getNumArgs() > 1 && std::exchange(ParenIfBinOp, true);150 if (Paren)151 OS << '(';152 ListSeparator LS(OpName == "any_of" ? " || " : " && ");153 for (auto *Arg : D->getArgs()) {154 OS << LS;155 if (emitFeaturesAux(TargetName, *Arg, ParenIfBinOp, OS))156 return true;157 }158 if (Paren)159 OS << ')';160 return false;161 }162 }163 return true;164}165 166void SubtargetFeatureInfo::emitPredicateCheck(167 raw_ostream &OS, ArrayRef<const Record *> Predicates) {168 ListSeparator LS(" && ");169 for (const Record *R : Predicates) {170 StringRef CondString = R->getValueAsString("CondString");171 if (CondString.empty())172 continue;173 OS << LS << '(' << CondString << ')';174 }175}176 177void SubtargetFeatureInfo::emitMCPredicateCheck(178 raw_ostream &OS, StringRef TargetName,179 ArrayRef<const Record *> Predicates) {180 auto MCPredicates = make_filter_range(Predicates, [](const Record *R) {181 return R->getValueAsBit("AssemblerMatcherPredicate");182 });183 184 if (MCPredicates.empty()) {185 OS << "false";186 return;187 }188 189 ListSeparator LS(" && ");190 bool ParenIfBinOp = range_size(MCPredicates) > 1;191 for (const Record *R : MCPredicates) {192 OS << LS;193 if (emitFeaturesAux(TargetName, *R->getValueAsDag("AssemblerCondDag"),194 ParenIfBinOp, OS))195 PrintFatalError(R, "Invalid AssemblerCondDag!");196 }197}198 199void SubtargetFeatureInfo::emitComputeAssemblerAvailableFeatures(200 StringRef TargetName, StringRef ClassName, StringRef FuncName,201 SubtargetFeatureInfoMap &SubtargetFeatures, raw_ostream &OS) {202 OS << "FeatureBitset ";203 if (!ClassName.empty())204 OS << TargetName << ClassName << "::\n";205 OS << FuncName << "(const FeatureBitset &FB) ";206 if (!ClassName.empty())207 OS << "const ";208 OS << "{\n";209 OS << " FeatureBitset Features;\n";210 for (const SubtargetFeatureInfo &SFI : make_second_range(SubtargetFeatures)) {211 const Record *Def = SFI.TheDef;212 213 OS << " if (";214 if (emitFeaturesAux(TargetName, *Def->getValueAsDag("AssemblerCondDag"),215 /*ParenIfBinOp=*/false, OS))216 PrintFatalError(Def, "Invalid AssemblerCondDag!");217 218 OS << ")\n";219 OS << " Features.set(" << SFI.getEnumBitName() << ");\n";220 }221 OS << " return Features;\n";222 OS << "}\n\n";223}224