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-exception 6 // 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 #include <map> 15 16 using namespace llvm; 17 18 #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP) 19 LLVM_DUMP_METHOD void SubtargetFeatureInfo::dump() const { 20 errs() << getEnumName() << " " << Index << "\n" << *TheDef; 21 } 22 #endif 23 24 std::vector<std::pair<Record *, SubtargetFeatureInfo>> 25 SubtargetFeatureInfo::getAll(const RecordKeeper &Records) { 26 std::vector<std::pair<Record *, SubtargetFeatureInfo>> SubtargetFeatures; 27 std::vector<Record *> AllPredicates = 28 Records.getAllDerivedDefinitions("Predicate"); 29 for (Record *Pred : AllPredicates) { 30 // Ignore predicates that are not intended for the assembler. 31 // 32 // The "AssemblerMatcherPredicate" string should be promoted to an argument 33 // if we re-use the machinery for non-assembler purposes in future. 34 if (!Pred->getValueAsBit("AssemblerMatcherPredicate")) 35 continue; 36 37 if (Pred->getName().empty()) 38 PrintFatalError(Pred->getLoc(), "Predicate has no name!"); 39 40 // Ignore always true predicates. 41 if (Pred->getValueAsString("CondString").empty()) 42 continue; 43 44 SubtargetFeatures.emplace_back( 45 Pred, SubtargetFeatureInfo(Pred, SubtargetFeatures.size())); 46 } 47 return SubtargetFeatures; 48 } 49 50 void SubtargetFeatureInfo::emitSubtargetFeatureBitEnumeration( 51 SubtargetFeatureInfoMap &SubtargetFeatures, raw_ostream &OS) { 52 OS << "// Bits for subtarget features that participate in " 53 << "instruction matching.\n"; 54 OS << "enum SubtargetFeatureBits : " 55 << getMinimalTypeForRange(SubtargetFeatures.size()) << " {\n"; 56 for (const auto &SF : SubtargetFeatures) { 57 const SubtargetFeatureInfo &SFI = SF.second; 58 OS << " " << SFI.getEnumBitName() << " = " << SFI.Index << ",\n"; 59 } 60 OS << "};\n\n"; 61 } 62 63 void SubtargetFeatureInfo::emitNameTable( 64 SubtargetFeatureInfoMap &SubtargetFeatures, raw_ostream &OS) { 65 // Need to sort the name table so that lookup by the log of the enum value 66 // gives the proper name. More specifically, for a feature of value 1<<n, 67 // SubtargetFeatureNames[n] should be the name of the feature. 68 uint64_t IndexUB = 0; 69 for (const auto &SF : SubtargetFeatures) 70 if (IndexUB <= SF.second.Index) 71 IndexUB = SF.second.Index+1; 72 73 std::vector<std::string> Names; 74 if (IndexUB > 0) 75 Names.resize(IndexUB); 76 for (const auto &SF : SubtargetFeatures) 77 Names[SF.second.Index] = SF.second.getEnumName(); 78 79 OS << "static const char *SubtargetFeatureNames[] = {\n"; 80 for (uint64_t I = 0; I < IndexUB; ++I) 81 OS << " \"" << Names[I] << "\",\n"; 82 83 // A small number of targets have no predicates. Null terminate the array to 84 // avoid a zero-length array. 85 OS << " nullptr\n" 86 << "};\n\n"; 87 } 88 89 void SubtargetFeatureInfo::emitComputeAvailableFeatures( 90 StringRef TargetName, StringRef ClassName, StringRef FuncName, 91 SubtargetFeatureInfoMap &SubtargetFeatures, raw_ostream &OS, 92 StringRef ExtraParams) { 93 OS << "PredicateBitset " << TargetName << ClassName << "::\n" 94 << FuncName << "(const " << TargetName << "Subtarget *Subtarget"; 95 if (!ExtraParams.empty()) 96 OS << ", " << ExtraParams; 97 OS << ") const {\n"; 98 OS << " PredicateBitset Features;\n"; 99 for (const auto &SF : SubtargetFeatures) { 100 const SubtargetFeatureInfo &SFI = SF.second; 101 StringRef CondStr = SFI.TheDef->getValueAsString("CondString"); 102 assert(!CondStr.empty() && "true predicate should have been filtered"); 103 104 OS << " if (" << CondStr << ")\n"; 105 OS << " Features.set(" << SFI.getEnumBitName() << ");\n"; 106 } 107 OS << " return Features;\n"; 108 OS << "}\n\n"; 109 } 110 111 void SubtargetFeatureInfo::emitComputeAssemblerAvailableFeatures( 112 StringRef TargetName, StringRef ClassName, StringRef FuncName, 113 SubtargetFeatureInfoMap &SubtargetFeatures, raw_ostream &OS) { 114 OS << "FeatureBitset " << TargetName << ClassName << "::\n" 115 << FuncName << "(const FeatureBitset &FB) const {\n"; 116 OS << " FeatureBitset Features;\n"; 117 for (const auto &SF : SubtargetFeatures) { 118 const SubtargetFeatureInfo &SFI = SF.second; 119 120 OS << " if ("; 121 122 const DagInit *D = SFI.TheDef->getValueAsDag("AssemblerCondDag"); 123 std::string CombineType = D->getOperator()->getAsString(); 124 if (CombineType != "any_of" && CombineType != "all_of") 125 PrintFatalError(SFI.TheDef->getLoc(), "Invalid AssemblerCondDag!"); 126 if (D->getNumArgs() == 0) 127 PrintFatalError(SFI.TheDef->getLoc(), "Invalid AssemblerCondDag!"); 128 bool IsOr = CombineType == "any_of"; 129 130 if (IsOr) 131 OS << "("; 132 133 ListSeparator LS(IsOr ? " || " : " && "); 134 for (auto *Arg : D->getArgs()) { 135 OS << LS; 136 if (auto *NotArg = dyn_cast<DagInit>(Arg)) { 137 if (NotArg->getOperator()->getAsString() != "not" || 138 NotArg->getNumArgs() != 1) 139 PrintFatalError(SFI.TheDef->getLoc(), "Invalid AssemblerCondDag!"); 140 Arg = NotArg->getArg(0); 141 OS << "!"; 142 } 143 if (!isa<DefInit>(Arg) || 144 !cast<DefInit>(Arg)->getDef()->isSubClassOf("SubtargetFeature")) 145 PrintFatalError(SFI.TheDef->getLoc(), "Invalid AssemblerCondDag!"); 146 OS << "FB[" << TargetName << "::" << Arg->getAsString() << "]"; 147 } 148 149 if (IsOr) 150 OS << ")"; 151 152 OS << ")\n"; 153 OS << " Features.set(" << SFI.getEnumBitName() << ");\n"; 154 } 155 OS << " return Features;\n"; 156 OS << "}\n\n"; 157 } 158