1 //===- TGParser.h - Parser for TableGen Files -------------------*- C++ -*-===// 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 class represents the Parser for tablegen files. 10 // 11 //===----------------------------------------------------------------------===// 12 13 #ifndef LLVM_LIB_TABLEGEN_TGPARSER_H 14 #define LLVM_LIB_TABLEGEN_TGPARSER_H 15 16 #include "TGLexer.h" 17 #include "llvm/ADT/Twine.h" 18 #include "llvm/Support/SourceMgr.h" 19 #include "llvm/TableGen/Error.h" 20 #include "llvm/TableGen/Record.h" 21 #include <map> 22 23 namespace llvm { 24 class Record; 25 class RecordVal; 26 class RecordKeeper; 27 class RecTy; 28 class Init; 29 struct ForeachLoop; 30 struct MultiClass; 31 struct SubClassReference; 32 struct SubMultiClassReference; 33 34 struct LetRecord { 35 StringInit *Name; 36 std::vector<unsigned> Bits; 37 Init *Value; 38 SMLoc Loc; 39 LetRecord(StringInit *N, ArrayRef<unsigned> B, Init *V, SMLoc L) 40 : Name(N), Bits(B), Value(V), Loc(L) { 41 } 42 }; 43 44 /// RecordsEntry - Can be either a record or a foreach loop. 45 struct RecordsEntry { 46 std::unique_ptr<Record> Rec; 47 std::unique_ptr<ForeachLoop> Loop; 48 49 void dump() const; 50 51 RecordsEntry() {} 52 RecordsEntry(std::unique_ptr<Record> Rec) : Rec(std::move(Rec)) {} 53 RecordsEntry(std::unique_ptr<ForeachLoop> Loop) 54 : Loop(std::move(Loop)) {} 55 }; 56 57 /// ForeachLoop - Record the iteration state associated with a for loop. 58 /// This is used to instantiate items in the loop body. 59 /// 60 /// IterVar is allowed to be null, in which case no iteration variable is 61 /// defined in the loop at all. (This happens when a ForeachLoop is 62 /// constructed by desugaring an if statement.) 63 struct ForeachLoop { 64 SMLoc Loc; 65 VarInit *IterVar; 66 Init *ListValue; 67 std::vector<RecordsEntry> Entries; 68 69 void dump() const; 70 71 ForeachLoop(SMLoc Loc, VarInit *IVar, Init *LValue) 72 : Loc(Loc), IterVar(IVar), ListValue(LValue) {} 73 }; 74 75 struct DefsetRecord { 76 SMLoc Loc; 77 RecTy *EltTy = nullptr; 78 SmallVector<Init *, 16> Elements; 79 }; 80 81 class TGLocalVarScope { 82 // A scope to hold local variable definitions from defvar. 83 std::map<std::string, Init *, std::less<>> vars; 84 std::unique_ptr<TGLocalVarScope> parent; 85 86 public: 87 TGLocalVarScope() = default; 88 TGLocalVarScope(std::unique_ptr<TGLocalVarScope> parent) 89 : parent(std::move(parent)) {} 90 91 std::unique_ptr<TGLocalVarScope> extractParent() { 92 // This is expected to be called just before we are destructed, so 93 // it doesn't much matter what state we leave 'parent' in. 94 return std::move(parent); 95 } 96 97 Init *getVar(StringRef Name) const { 98 auto It = vars.find(Name); 99 if (It != vars.end()) 100 return It->second; 101 if (parent) 102 return parent->getVar(Name); 103 return nullptr; 104 } 105 106 bool varAlreadyDefined(StringRef Name) const { 107 // When we check whether a variable is already defined, for the purpose of 108 // reporting an error on redefinition, we don't look up to the parent 109 // scope, because it's all right to shadow an outer definition with an 110 // inner one. 111 return vars.find(Name) != vars.end(); 112 } 113 114 void addVar(StringRef Name, Init *I) { 115 bool Ins = vars.insert(std::make_pair(Name, I)).second; 116 (void)Ins; 117 assert(Ins && "Local variable already exists"); 118 } 119 }; 120 121 struct MultiClass { 122 Record Rec; // Placeholder for template args and Name. 123 std::vector<RecordsEntry> Entries; 124 125 void dump() const; 126 127 MultiClass(StringRef Name, SMLoc Loc, RecordKeeper &Records) : 128 Rec(Name, Loc, Records) {} 129 }; 130 131 class TGParser { 132 TGLexer Lex; 133 std::vector<SmallVector<LetRecord, 4>> LetStack; 134 std::map<std::string, std::unique_ptr<MultiClass>> MultiClasses; 135 136 /// Loops - Keep track of any foreach loops we are within. 137 /// 138 std::vector<std::unique_ptr<ForeachLoop>> Loops; 139 140 SmallVector<DefsetRecord *, 2> Defsets; 141 142 /// CurMultiClass - If we are parsing a 'multiclass' definition, this is the 143 /// current value. 144 MultiClass *CurMultiClass; 145 146 /// CurLocalScope - Innermost of the current nested scopes for 'defvar' local 147 /// variables. 148 std::unique_ptr<TGLocalVarScope> CurLocalScope; 149 150 // Record tracker 151 RecordKeeper &Records; 152 153 // A "named boolean" indicating how to parse identifiers. Usually 154 // identifiers map to some existing object but in special cases 155 // (e.g. parsing def names) no such object exists yet because we are 156 // in the middle of creating in. For those situations, allow the 157 // parser to ignore missing object errors. 158 enum IDParseMode { 159 ParseValueMode, // We are parsing a value we expect to look up. 160 ParseNameMode, // We are parsing a name of an object that does not yet 161 // exist. 162 }; 163 164 public: 165 TGParser(SourceMgr &SM, ArrayRef<std::string> Macros, 166 RecordKeeper &records) 167 : Lex(SM, Macros), CurMultiClass(nullptr), Records(records) {} 168 169 /// ParseFile - Main entrypoint for parsing a tblgen file. These parser 170 /// routines return true on error, or false on success. 171 bool ParseFile(); 172 173 bool Error(SMLoc L, const Twine &Msg) const { 174 PrintError(L, Msg); 175 return true; 176 } 177 bool TokError(const Twine &Msg) const { 178 return Error(Lex.getLoc(), Msg); 179 } 180 const TGLexer::DependenciesSetTy &getDependencies() const { 181 return Lex.getDependencies(); 182 } 183 184 TGLocalVarScope *PushLocalScope() { 185 CurLocalScope = std::make_unique<TGLocalVarScope>(std::move(CurLocalScope)); 186 // Returns a pointer to the new scope, so that the caller can pass it back 187 // to PopLocalScope which will check by assertion that the pushes and pops 188 // match up properly. 189 return CurLocalScope.get(); 190 } 191 void PopLocalScope(TGLocalVarScope *ExpectedStackTop) { 192 assert(ExpectedStackTop == CurLocalScope.get() && 193 "Mismatched pushes and pops of local variable scopes"); 194 CurLocalScope = CurLocalScope->extractParent(); 195 } 196 197 private: // Semantic analysis methods. 198 bool AddValue(Record *TheRec, SMLoc Loc, const RecordVal &RV); 199 bool SetValue(Record *TheRec, SMLoc Loc, Init *ValName, 200 ArrayRef<unsigned> BitList, Init *V, 201 bool AllowSelfAssignment = false); 202 bool AddSubClass(Record *Rec, SubClassReference &SubClass); 203 bool AddSubClass(RecordsEntry &Entry, SubClassReference &SubClass); 204 bool AddSubMultiClass(MultiClass *CurMC, 205 SubMultiClassReference &SubMultiClass); 206 207 using SubstStack = SmallVector<std::pair<Init *, Init *>, 8>; 208 209 bool addEntry(RecordsEntry E); 210 bool resolve(const ForeachLoop &Loop, SubstStack &Stack, bool Final, 211 std::vector<RecordsEntry> *Dest, SMLoc *Loc = nullptr); 212 bool resolve(const std::vector<RecordsEntry> &Source, SubstStack &Substs, 213 bool Final, std::vector<RecordsEntry> *Dest, 214 SMLoc *Loc = nullptr); 215 bool addDefOne(std::unique_ptr<Record> Rec); 216 217 private: // Parser methods. 218 bool ParseObjectList(MultiClass *MC = nullptr); 219 bool ParseObject(MultiClass *MC); 220 bool ParseClass(); 221 bool ParseMultiClass(); 222 bool ParseDefm(MultiClass *CurMultiClass); 223 bool ParseDef(MultiClass *CurMultiClass); 224 bool ParseDefset(); 225 bool ParseDefvar(); 226 bool ParseForeach(MultiClass *CurMultiClass); 227 bool ParseIf(MultiClass *CurMultiClass); 228 bool ParseIfBody(MultiClass *CurMultiClass, StringRef Kind); 229 bool ParseTopLevelLet(MultiClass *CurMultiClass); 230 void ParseLetList(SmallVectorImpl<LetRecord> &Result); 231 232 bool ParseObjectBody(Record *CurRec); 233 bool ParseBody(Record *CurRec); 234 bool ParseBodyItem(Record *CurRec); 235 236 bool ParseTemplateArgList(Record *CurRec); 237 Init *ParseDeclaration(Record *CurRec, bool ParsingTemplateArgs); 238 VarInit *ParseForeachDeclaration(Init *&ForeachListValue); 239 240 SubClassReference ParseSubClassReference(Record *CurRec, bool isDefm); 241 SubMultiClassReference ParseSubMultiClassReference(MultiClass *CurMC); 242 243 Init *ParseIDValue(Record *CurRec, StringInit *Name, SMLoc NameLoc, 244 IDParseMode Mode = ParseValueMode); 245 Init *ParseSimpleValue(Record *CurRec, RecTy *ItemType = nullptr, 246 IDParseMode Mode = ParseValueMode); 247 Init *ParseValue(Record *CurRec, RecTy *ItemType = nullptr, 248 IDParseMode Mode = ParseValueMode); 249 void ParseValueList(SmallVectorImpl<llvm::Init*> &Result, Record *CurRec, 250 Record *ArgsRec = nullptr, RecTy *EltTy = nullptr); 251 void ParseDagArgList( 252 SmallVectorImpl<std::pair<llvm::Init*, StringInit*>> &Result, 253 Record *CurRec); 254 bool ParseOptionalRangeList(SmallVectorImpl<unsigned> &Ranges); 255 bool ParseOptionalBitList(SmallVectorImpl<unsigned> &Ranges); 256 void ParseRangeList(SmallVectorImpl<unsigned> &Result); 257 bool ParseRangePiece(SmallVectorImpl<unsigned> &Ranges, 258 TypedInit *FirstItem = nullptr); 259 RecTy *ParseType(); 260 Init *ParseOperation(Record *CurRec, RecTy *ItemType); 261 Init *ParseOperationCond(Record *CurRec, RecTy *ItemType); 262 RecTy *ParseOperatorType(); 263 Init *ParseObjectName(MultiClass *CurMultiClass); 264 Record *ParseClassID(); 265 MultiClass *ParseMultiClassID(); 266 bool ApplyLetStack(Record *CurRec); 267 bool ApplyLetStack(RecordsEntry &Entry); 268 }; 269 270 } // end namespace llvm 271 272 #endif 273