utils/TableGen/TGParser.cpp

   1 //===- TGParser.cpp - Parser for TableGen Files ---------------------------===//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file is distributed under the University of Illinois Open Source
   6 // License. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9 //
  10 // Implement the Parser for TableGen.
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #include "TGParser.h"
  15 #include "Record.h"
  16 #include "llvm/ADT/StringExtras.h"
  17 #include <algorithm>
  18 #include <sstream>
  19 #include "llvm/ADT/SmallVector.h"
  20 #include "llvm/Support/CommandLine.h"
  21 using namespace llvm;
  22
  23 //===----------------------------------------------------------------------===//
  24 // Support Code for the Semantic Actions.
  25 //===----------------------------------------------------------------------===//
  26
  27 namespace llvm {
  28 struct SubClassReference {
  29   SMLoc RefLoc;
  30   Record *Rec;
  31   std::vector<Init*> TemplateArgs;
  32   SubClassReference() : Rec(0) {}
  33
  34   bool isInvalid() const { return Rec == 0; }
  35 };
  36
  37 struct SubMultiClassReference {
  38   SMLoc RefLoc;
  39   MultiClass *MC;
  40   std::vector<Init*> TemplateArgs;
  41   SubMultiClassReference() : MC(0) {}
  42
  43   bool isInvalid() const { return MC == 0; }
  44   void dump() const;
  45 };
  46
  47 void SubMultiClassReference::dump() const {
  48   errs() << "Multiclass:\n";
  49
  50   MC->dump();
  51
  52   errs() << "Template args:\n";
  53   for (std::vector<Init *>::const_iterator i = TemplateArgs.begin(),
  54          iend = TemplateArgs.end();
  55        i != iend;
  56        ++i) {
  57     (*i)->dump();
  58   }
  59 }
  60
  61 } // end namespace llvm
  62
  63 bool TGParser::AddValue(Record *CurRec, SMLoc Loc, const RecordVal &RV) {
  64   if (CurRec == 0)
  65     CurRec = &CurMultiClass->Rec;
  66
  67   if (RecordVal *ERV = CurRec->getValue(RV.getName())) {
  68     // The value already exists in the class, treat this as a set.
  69     if (ERV->setValue(RV.getValue()))
  70       return Error(Loc, "New definition of '" + RV.getName() + "' of type '" +
  71                    RV.getType()->getAsString() + "' is incompatible with " +
  72                    "previous definition of type '" +
  73                    ERV->getType()->getAsString() + "'");
  74   } else {
  75     CurRec->addValue(RV);
  76   }
  77   return false;
  78 }
  79
  80 /// SetValue -
  81 /// Return true on error, false on success.
  82 bool TGParser::SetValue(Record *CurRec, SMLoc Loc, const std::string &ValName,
  83                         const std::vector<unsigned> &BitList, Init *V) {
  84   if (!V) return false;
  85
  86   if (CurRec == 0) CurRec = &CurMultiClass->Rec;
  87
  88   RecordVal *RV = CurRec->getValue(ValName);
  89   if (RV == 0)
  90     return Error(Loc, "Value '" + ValName + "' unknown!");
  91
  92   // Do not allow assignments like 'X = X'.  This will just cause infinite loops
  93   // in the resolution machinery.
  94   if (BitList.empty())
  95     if (VarInit *VI = dynamic_cast<VarInit*>(V))
  96       if (VI->getName() == ValName)
  97         return false;
  98
  99   // If we are assigning to a subset of the bits in the value... then we must be
 100   // assigning to a field of BitsRecTy, which must have a BitsInit
 101   // initializer.
 102   //
 103   if (!BitList.empty()) {
 104     BitsInit *CurVal = dynamic_cast<BitsInit*>(RV->getValue());
 105     if (CurVal == 0)
 106       return Error(Loc, "Value '" + ValName + "' is not a bits type");
 107
 108     // Convert the incoming value to a bits type of the appropriate size...
 109     Init *BI = V->convertInitializerTo(new BitsRecTy(BitList.size()));
 110     if (BI == 0) {
 111       V->convertInitializerTo(new BitsRecTy(BitList.size()));
 112       return Error(Loc, "Initializer is not compatible with bit range");
 113     }
 114
 115     // We should have a BitsInit type now.
 116     BitsInit *BInit = dynamic_cast<BitsInit*>(BI);
 117     assert(BInit != 0);
 118
 119     BitsInit *NewVal = new BitsInit(CurVal->getNumBits());
 120
 121     // Loop over bits, assigning values as appropriate.
 122     for (unsigned i = 0, e = BitList.size(); i != e; ++i) {
 123       unsigned Bit = BitList[i];
 124       if (NewVal->getBit(Bit))
 125         return Error(Loc, "Cannot set bit #" + utostr(Bit) + " of value '" +
 126                      ValName + "' more than once");
 127       NewVal->setBit(Bit, BInit->getBit(i));
 128     }
 129
 130     for (unsigned i = 0, e = CurVal->getNumBits(); i != e; ++i)
 131       if (NewVal->getBit(i) == 0)
 132         NewVal->setBit(i, CurVal->getBit(i));
 133
 134     V = NewVal;
 135   }
 136
 137   if (RV->setValue(V))
 138    return Error(Loc, "Value '" + ValName + "' of type '" +
 139                 RV->getType()->getAsString() +
 140                 "' is incompatible with initializer '" + V->getAsString() +"'");
 141   return false;
 142 }
 143
 144 /// AddSubClass - Add SubClass as a subclass to CurRec, resolving its template
 145 /// args as SubClass's template arguments.
 146 bool TGParser::AddSubClass(Record *CurRec, SubClassReference &SubClass) {
 147   Record *SC = SubClass.Rec;
 148   // Add all of the values in the subclass into the current class.
 149   const std::vector<RecordVal> &Vals = SC->getValues();
 150   for (unsigned i = 0, e = Vals.size(); i != e; ++i)
 151     if (AddValue(CurRec, SubClass.RefLoc, Vals[i]))
 152       return true;
 153
 154   const std::vector<std::string> &TArgs = SC->getTemplateArgs();
 155
 156   // Ensure that an appropriate number of template arguments are specified.
 157   if (TArgs.size() < SubClass.TemplateArgs.size())
 158     return Error(SubClass.RefLoc, "More template args specified than expected");
 159
 160   // Loop over all of the template arguments, setting them to the specified
 161   // value or leaving them as the default if necessary.
 162   for (unsigned i = 0, e = TArgs.size(); i != e; ++i) {
 163     if (i < SubClass.TemplateArgs.size()) {
 164       // If a value is specified for this template arg, set it now.
 165       if (SetValue(CurRec, SubClass.RefLoc, TArgs[i], std::vector<unsigned>(),
 166                    SubClass.TemplateArgs[i]))
 167         return true;
 168
 169       // Resolve it next.
 170       CurRec->resolveReferencesTo(CurRec->getValue(TArgs[i]));
 171
 172       // Now remove it.
 173       CurRec->removeValue(TArgs[i]);
 174
 175     } else if (!CurRec->getValue(TArgs[i])->getValue()->isComplete()) {
 176       return Error(SubClass.RefLoc,"Value not specified for template argument #"
 177                    + utostr(i) + " (" + TArgs[i] + ") of subclass '" +
 178                    SC->getName() + "'!");
 179     }
 180   }
 181
 182   // Since everything went well, we can now set the "superclass" list for the
 183   // current record.
 184   const std::vector<Record*> &SCs = SC->getSuperClasses();
 185   for (unsigned i = 0, e = SCs.size(); i != e; ++i) {
 186     if (CurRec->isSubClassOf(SCs[i]))
 187       return Error(SubClass.RefLoc,
 188                    "Already subclass of '" + SCs[i]->getName() + "'!\n");
 189     CurRec->addSuperClass(SCs[i]);
 190   }
 191
 192   if (CurRec->isSubClassOf(SC))
 193     return Error(SubClass.RefLoc,
 194                  "Already subclass of '" + SC->getName() + "'!\n");
 195   CurRec->addSuperClass(SC);
 196   return false;
 197 }
 198
 199 /// AddSubMultiClass - Add SubMultiClass as a subclass to
 200 /// CurMC, resolving its template args as SubMultiClass's
 201 /// template arguments.
 202 bool TGParser::AddSubMultiClass(MultiClass *CurMC,
 203                                 SubMultiClassReference &SubMultiClass) {
 204   MultiClass *SMC = SubMultiClass.MC;
 205   Record *CurRec = &CurMC->Rec;
 206
 207   const std::vector<RecordVal> &MCVals = CurRec->getValues();
 208
 209   // Add all of the values in the subclass into the current class.
 210   const std::vector<RecordVal> &SMCVals = SMC->Rec.getValues();
 211   for (unsigned i = 0, e = SMCVals.size(); i != e; ++i)
 212     if (AddValue(CurRec, SubMultiClass.RefLoc, SMCVals[i]))
 213       return true;
 214
 215   int newDefStart = CurMC->DefPrototypes.size();
 216
 217   // Add all of the defs in the subclass into the current multiclass.
 218   for (MultiClass::RecordVector::const_iterator i = SMC->DefPrototypes.begin(),
 219          iend = SMC->DefPrototypes.end();
 220        i != iend;
 221        ++i) {
 222     // Clone the def and add it to the current multiclass
 223     Record *NewDef = new Record(**i);
 224
 225     // Add all of the values in the superclass into the current def.
 226     for (unsigned i = 0, e = MCVals.size(); i != e; ++i)
 227       if (AddValue(NewDef, SubMultiClass.RefLoc, MCVals[i]))
 228         return true;
 229
 230     CurMC->DefPrototypes.push_back(NewDef);
 231   }
 232
 233   const std::vector<std::string> &SMCTArgs = SMC->Rec.getTemplateArgs();
 234
 235   // Ensure that an appropriate number of template arguments are
 236   // specified.
 237   if (SMCTArgs.size() < SubMultiClass.TemplateArgs.size())
 238     return Error(SubMultiClass.RefLoc,
 239                  "More template args specified than expected");
 240
 241   // Loop over all of the template arguments, setting them to the specified
 242   // value or leaving them as the default if necessary.
 243   for (unsigned i = 0, e = SMCTArgs.size(); i != e; ++i) {
 244     if (i < SubMultiClass.TemplateArgs.size()) {
 245       // If a value is specified for this template arg, set it in the
 246       // superclass now.
 247       if (SetValue(CurRec, SubMultiClass.RefLoc, SMCTArgs[i],
 248                    std::vector<unsigned>(),
 249                    SubMultiClass.TemplateArgs[i]))
 250         return true;
 251
 252       // Resolve it next.
 253       CurRec->resolveReferencesTo(CurRec->getValue(SMCTArgs[i]));
 254
 255       // Now remove it.
 256       CurRec->removeValue(SMCTArgs[i]);
 257
 258       // If a value is specified for this template arg, set it in the
 259       // new defs now.
 260       for (MultiClass::RecordVector::iterator j =
 261              CurMC->DefPrototypes.begin() + newDefStart,
 262              jend = CurMC->DefPrototypes.end();
 263            j != jend;
 264            ++j) {
 265         Record *Def = *j;
 266
 267         if (SetValue(Def, SubMultiClass.RefLoc, SMCTArgs[i],
 268                      std::vector<unsigned>(),
 269                      SubMultiClass.TemplateArgs[i]))
 270           return true;
 271
 272         // Resolve it next.
 273         Def->resolveReferencesTo(Def->getValue(SMCTArgs[i]));
 274
 275         // Now remove it
 276         Def->removeValue(SMCTArgs[i]);
 277       }
 278     } else if (!CurRec->getValue(SMCTArgs[i])->getValue()->isComplete()) {
 279       return Error(SubMultiClass.RefLoc,
 280                    "Value not specified for template argument #"
 281                    + utostr(i) + " (" + SMCTArgs[i] + ") of subclass '" +
 282                    SMC->Rec.getName() + "'!");
 283     }
 284   }
 285
 286   return false;
 287 }
 288
 289 //===----------------------------------------------------------------------===//
 290 // Parser Code
 291 //===----------------------------------------------------------------------===//
 292
 293 /// isObjectStart - Return true if this is a valid first token for an Object.
 294 static bool isObjectStart(tgtok::TokKind K) {
 295   return K == tgtok::Class || K == tgtok::Def ||
 296          K == tgtok::Defm || K == tgtok::Let || K == tgtok::MultiClass;
 297 }
 298
 299 static std::string GetNewAnonymousName() {
 300   static unsigned AnonCounter = 0;
 301   return "anonymous."+utostr(AnonCounter++);
 302 }
 303
 304 /// ParseObjectName - If an object name is specified, return it.  Otherwise,
 305 /// return an anonymous name.
 306 ///   ObjectName ::= ID
 307 ///   ObjectName ::= /*empty*/
 308 ///
 309 std::string TGParser::ParseObjectName() {
 310   if (Lex.getCode() != tgtok::Id)
 311     return GetNewAnonymousName();
 312
 313   std::string Ret = Lex.getCurStrVal();
 314   Lex.Lex();
 315   return Ret;
 316 }
 317
 318
 319 /// ParseClassID - Parse and resolve a reference to a class name.  This returns
 320 /// null on error.
 321 ///
 322 ///    ClassID ::= ID
 323 ///
 324 Record *TGParser::ParseClassID() {
 325   if (Lex.getCode() != tgtok::Id) {
 326     TokError("expected name for ClassID");
 327     return 0;
 328   }
 329
 330   Record *Result = Records.getClass(Lex.getCurStrVal());
 331   if (Result == 0)
 332     TokError("Couldn't find class '" + Lex.getCurStrVal() + "'");
 333
 334   Lex.Lex();
 335   return Result;
 336 }
 337
 338 /// ParseMultiClassID - Parse and resolve a reference to a multiclass name.
 339 /// This returns null on error.
 340 ///
 341 ///    MultiClassID ::= ID
 342 ///
 343 MultiClass *TGParser::ParseMultiClassID() {
 344   if (Lex.getCode() != tgtok::Id) {
 345     TokError("expected name for ClassID");
 346     return 0;
 347   }
 348
 349   MultiClass *Result = MultiClasses[Lex.getCurStrVal()];
 350   if (Result == 0)
 351     TokError("Couldn't find class '" + Lex.getCurStrVal() + "'");
 352
 353   Lex.Lex();
 354   return Result;
 355 }
 356
 357 Record *TGParser::ParseDefmID() {
 358   if (Lex.getCode() != tgtok::Id) {
 359     TokError("expected multiclass name");
 360     return 0;
 361   }
 362
 363   MultiClass *MC = MultiClasses[Lex.getCurStrVal()];
 364   if (MC == 0) {
 365     TokError("Couldn't find multiclass '" + Lex.getCurStrVal() + "'");
 366     return 0;
 367   }
 368
 369   Lex.Lex();
 370   return &MC->Rec;
 371 }
 372
 373
 374 /// ParseSubClassReference - Parse a reference to a subclass or to a templated
 375 /// subclass.  This returns a SubClassRefTy with a null Record* on error.
 376 ///
 377 ///  SubClassRef ::= ClassID
 378 ///  SubClassRef ::= ClassID '<' ValueList '>'
 379 ///
 380 SubClassReference TGParser::
 381 ParseSubClassReference(Record *CurRec, bool isDefm) {
 382   SubClassReference Result;
 383   Result.RefLoc = Lex.getLoc();
 384
 385   if (isDefm)
 386     Result.Rec = ParseDefmID();
 387   else
 388     Result.Rec = ParseClassID();
 389   if (Result.Rec == 0) return Result;
 390
 391   // If there is no template arg list, we're done.
 392   if (Lex.getCode() != tgtok::less)
 393     return Result;
 394   Lex.Lex();  // Eat the '<'
 395
 396   if (Lex.getCode() == tgtok::greater) {
 397     TokError("subclass reference requires a non-empty list of template values");
 398     Result.Rec = 0;
 399     return Result;
 400   }
 401
 402   Result.TemplateArgs = ParseValueList(CurRec, Result.Rec);
 403   if (Result.TemplateArgs.empty()) {
 404     Result.Rec = 0;   // Error parsing value list.
 405     return Result;
 406   }
 407
 408   if (Lex.getCode() != tgtok::greater) {
 409     TokError("expected '>' in template value list");
 410     Result.Rec = 0;
 411     return Result;
 412   }
 413   Lex.Lex();
 414
 415   return Result;
 416 }
 417
 418 /// ParseSubMultiClassReference - Parse a reference to a subclass or to a
 419 /// templated submulticlass.  This returns a SubMultiClassRefTy with a null
 420 /// Record* on error.
 421 ///
 422 ///  SubMultiClassRef ::= MultiClassID
 423 ///  SubMultiClassRef ::= MultiClassID '<' ValueList '>'
 424 ///
 425 SubMultiClassReference TGParser::
 426 ParseSubMultiClassReference(MultiClass *CurMC) {
 427   SubMultiClassReference Result;
 428   Result.RefLoc = Lex.getLoc();
 429
 430   Result.MC = ParseMultiClassID();
 431   if (Result.MC == 0) return Result;
 432
 433   // If there is no template arg list, we're done.
 434   if (Lex.getCode() != tgtok::less)
 435     return Result;
 436   Lex.Lex();  // Eat the '<'
 437
 438   if (Lex.getCode() == tgtok::greater) {
 439     TokError("subclass reference requires a non-empty list of template values");
 440     Result.MC = 0;
 441     return Result;
 442   }
 443
 444   Result.TemplateArgs = ParseValueList(&CurMC->Rec, &Result.MC->Rec);
 445   if (Result.TemplateArgs.empty()) {
 446     Result.MC = 0;   // Error parsing value list.
 447     return Result;
 448   }
 449
 450   if (Lex.getCode() != tgtok::greater) {
 451     TokError("expected '>' in template value list");
 452     Result.MC = 0;
 453     return Result;
 454   }
 455   Lex.Lex();
 456
 457   return Result;
 458 }
 459
 460 /// ParseRangePiece - Parse a bit/value range.
 461 ///   RangePiece ::= INTVAL
 462 ///   RangePiece ::= INTVAL '-' INTVAL
 463 ///   RangePiece ::= INTVAL INTVAL
 464 bool TGParser::ParseRangePiece(std::vector<unsigned> &Ranges) {
 465   if (Lex.getCode() != tgtok::IntVal) {
 466     TokError("expected integer or bitrange");
 467     return true;
 468   }
 469   int64_t Start = Lex.getCurIntVal();
 470   int64_t End;
 471
 472   if (Start < 0)
 473     return TokError("invalid range, cannot be negative");
 474
 475   switch (Lex.Lex()) {  // eat first character.
 476   default:
 477     Ranges.push_back(Start);
 478     return false;
 479   case tgtok::minus:
 480     if (Lex.Lex() != tgtok::IntVal) {
 481       TokError("expected integer value as end of range");
 482       return true;
 483     }
 484     End = Lex.getCurIntVal();
 485     break;
 486   case tgtok::IntVal:
 487     End = -Lex.getCurIntVal();
 488     break;
 489   }
 490   if (End < 0)
 491     return TokError("invalid range, cannot be negative");
 492   Lex.Lex();
 493
 494   // Add to the range.
 495   if (Start < End) {
 496     for (; Start <= End; ++Start)
 497       Ranges.push_back(Start);
 498   } else {
 499     for (; Start >= End; --Start)
 500       Ranges.push_back(Start);
 501   }
 502   return false;
 503 }
 504
 505 /// ParseRangeList - Parse a list of scalars and ranges into scalar values.
 506 ///
 507 ///   RangeList ::= RangePiece (',' RangePiece)*
 508 ///
 509 std::vector<unsigned> TGParser::ParseRangeList() {
 510   std::vector<unsigned> Result;
 511
 512   // Parse the first piece.
 513   if (ParseRangePiece(Result))
 514     return std::vector<unsigned>();
 515   while (Lex.getCode() == tgtok::comma) {
 516     Lex.Lex();  // Eat the comma.
 517
 518     // Parse the next range piece.
 519     if (ParseRangePiece(Result))
 520       return std::vector<unsigned>();
 521   }
 522   return Result;
 523 }
 524
 525 /// ParseOptionalRangeList - Parse either a range list in <>'s or nothing.
 526 ///   OptionalRangeList ::= '<' RangeList '>'
 527 ///   OptionalRangeList ::= /*empty*/
 528 bool TGParser::ParseOptionalRangeList(std::vector<unsigned> &Ranges) {
 529   if (Lex.getCode() != tgtok::less)
 530     return false;
 531
 532   SMLoc StartLoc = Lex.getLoc();
 533   Lex.Lex(); // eat the '<'
 534
 535   // Parse the range list.
 536   Ranges = ParseRangeList();
 537   if (Ranges.empty()) return true;
 538
 539   if (Lex.getCode() != tgtok::greater) {
 540     TokError("expected '>' at end of range list");
 541     return Error(StartLoc, "to match this '<'");
 542   }
 543   Lex.Lex();   // eat the '>'.
 544   return false;
 545 }
 546
 547 /// ParseOptionalBitList - Parse either a bit list in {}'s or nothing.
 548 ///   OptionalBitList ::= '{' RangeList '}'
 549 ///   OptionalBitList ::= /*empty*/
 550 bool TGParser::ParseOptionalBitList(std::vector<unsigned> &Ranges) {
 551   if (Lex.getCode() != tgtok::l_brace)
 552     return false;
 553
 554   SMLoc StartLoc = Lex.getLoc();
 555   Lex.Lex(); // eat the '{'
 556
 557   // Parse the range list.
 558   Ranges = ParseRangeList();
 559   if (Ranges.empty()) return true;
 560
 561   if (Lex.getCode() != tgtok::r_brace) {
 562     TokError("expected '}' at end of bit list");
 563     return Error(StartLoc, "to match this '{'");
 564   }
 565   Lex.Lex();   // eat the '}'.
 566   return false;
 567 }
 568
 569
 570 /// ParseType - Parse and return a tblgen type.  This returns null on error.
 571 ///
 572 ///   Type ::= STRING                       // string type
 573 ///   Type ::= BIT                          // bit type
 574 ///   Type ::= BITS '<' INTVAL '>'          // bits<x> type
 575 ///   Type ::= INT                          // int type
 576 ///   Type ::= LIST '<' Type '>'            // list<x> type
 577 ///   Type ::= CODE                         // code type
 578 ///   Type ::= DAG                          // dag type
 579 ///   Type ::= ClassID                      // Record Type
 580 ///
 581 RecTy *TGParser::ParseType() {
 582   switch (Lex.getCode()) {
 583   default: TokError("Unknown token when expecting a type"); return 0;
 584   case tgtok::String: Lex.Lex(); return new StringRecTy();
 585   case tgtok::Bit:    Lex.Lex(); return new BitRecTy();
 586   case tgtok::Int:    Lex.Lex(); return new IntRecTy();
 587   case tgtok::Code:   Lex.Lex(); return new CodeRecTy();
 588   case tgtok::Dag:    Lex.Lex(); return new DagRecTy();
 589   case tgtok::Id:
 590     if (Record *R = ParseClassID()) return new RecordRecTy(R);
 591     return 0;
 592   case tgtok::Bits: {
 593     if (Lex.Lex() != tgtok::less) { // Eat 'bits'
 594       TokError("expected '<' after bits type");
 595       return 0;
 596     }
 597     if (Lex.Lex() != tgtok::IntVal) {  // Eat '<'
 598       TokError("expected integer in bits<n> type");
 599       return 0;
 600     }
 601     uint64_t Val = Lex.getCurIntVal();
 602     if (Lex.Lex() != tgtok::greater) {  // Eat count.
 603       TokError("expected '>' at end of bits<n> type");
 604       return 0;
 605     }
 606     Lex.Lex();  // Eat '>'
 607     return new BitsRecTy(Val);
 608   }
 609   case tgtok::List: {
 610     if (Lex.Lex() != tgtok::less) { // Eat 'bits'
 611       TokError("expected '<' after list type");
 612       return 0;
 613     }
 614     Lex.Lex();  // Eat '<'
 615     RecTy *SubType = ParseType();
 616     if (SubType == 0) return 0;
 617
 618     if (Lex.getCode() != tgtok::greater) {
 619       TokError("expected '>' at end of list<ty> type");
 620       return 0;
 621     }
 622     Lex.Lex();  // Eat '>'
 623     return new ListRecTy(SubType);
 624   }
 625   }
 626 }
 627
 628 /// ParseIDValue - Parse an ID as a value and decode what it means.
 629 ///
 630 ///  IDValue ::= ID [def local value]
 631 ///  IDValue ::= ID [def template arg]
 632 ///  IDValue ::= ID [multiclass local value]
 633 ///  IDValue ::= ID [multiclass template argument]
 634 ///  IDValue ::= ID [def name]
 635 ///
 636 Init *TGParser::ParseIDValue(Record *CurRec) {
 637   assert(Lex.getCode() == tgtok::Id && "Expected ID in ParseIDValue");
 638   std::string Name = Lex.getCurStrVal();
 639   SMLoc Loc = Lex.getLoc();
 640   Lex.Lex();
 641   return ParseIDValue(CurRec, Name, Loc);
 642 }
 643
 644 /// ParseIDValue - This is just like ParseIDValue above, but it assumes the ID
 645 /// has already been read.
 646 Init *TGParser::ParseIDValue(Record *CurRec,
 647                              const std::string &Name, SMLoc NameLoc) {
 648   if (CurRec) {
 649     if (const RecordVal *RV = CurRec->getValue(Name))
 650       return new VarInit(Name, RV->getType());
 651
 652     std::string TemplateArgName = CurRec->getName()+":"+Name;
 653     if (CurRec->isTemplateArg(TemplateArgName)) {
 654       const RecordVal *RV = CurRec->getValue(TemplateArgName);
 655       assert(RV && "Template arg doesn't exist??");
 656       return new VarInit(TemplateArgName, RV->getType());
 657     }
 658   }
 659
 660   if (CurMultiClass) {
 661     std::string MCName = CurMultiClass->Rec.getName()+"::"+Name;
 662     if (CurMultiClass->Rec.isTemplateArg(MCName)) {
 663       const RecordVal *RV = CurMultiClass->Rec.getValue(MCName);
 664       assert(RV && "Template arg doesn't exist??");
 665       return new VarInit(MCName, RV->getType());
 666     }
 667   }
 668
 669   if (Record *D = Records.getDef(Name))
 670     return new DefInit(D);
 671
 672   Error(NameLoc, "Variable not defined: '" + Name + "'");
 673   return 0;
 674 }
 675
 676 /// ParseOperation - Parse an operator.  This returns null on error.
 677 ///
 678 /// Operation ::= XOperator ['<' Type '>'] '(' Args ')'
 679 ///
 680 Init *TGParser::ParseOperation(Record *CurRec) {
 681   switch (Lex.getCode()) {
 682   default:
 683     TokError("unknown operation");
 684     return 0;
 685     break;
 686   case tgtok::XCar:
 687   case tgtok::XCdr:
 688   case tgtok::XNull:
 689   case tgtok::XCast: {  // Value ::= !unop '(' Value ')'
 690     UnOpInit::UnaryOp Code;
 691     RecTy *Type = 0;
 692
 693     switch (Lex.getCode()) {
 694     default: assert(0 && "Unhandled code!");
 695     case tgtok::XCast:
 696       Lex.Lex();  // eat the operation
 697       Code = UnOpInit::CAST;
 698
 699       Type = ParseOperatorType();
 700
 701       if (Type == 0) {
 702         TokError("did not get type for unary operator");
 703         return 0;
 704       }
 705
 706       break;
 707     case tgtok::XCar:
 708       Lex.Lex();  // eat the operation
 709       Code = UnOpInit::CAR;
 710       break;
 711     case tgtok::XCdr:
 712       Lex.Lex();  // eat the operation
 713       Code = UnOpInit::CDR;
 714       break;
 715     case tgtok::XNull:
 716       Lex.Lex();  // eat the operation
 717       Code = UnOpInit::LNULL;
 718       Type = new IntRecTy;
 719       break;
 720     }
 721     if (Lex.getCode() != tgtok::l_paren) {
 722       TokError("expected '(' after unary operator");
 723       return 0;
 724     }
 725     Lex.Lex();  // eat the '('
 726
 727     Init *LHS = ParseValue(CurRec);
 728     if (LHS == 0) return 0;
 729
 730     if (Code == UnOpInit::CAR
 731         || Code == UnOpInit::CDR
 732         || Code == UnOpInit::LNULL) {
 733       ListInit *LHSl = dynamic_cast<ListInit*>(LHS);
 734       StringInit *LHSs = dynamic_cast<StringInit*>(LHS);
 735       TypedInit *LHSt = dynamic_cast<TypedInit*>(LHS);
 736       if (LHSl == 0 && LHSs == 0 && LHSt == 0) {
 737         TokError("expected list or string type argument in unary operator");
 738         return 0;
 739       }
 740       if (LHSt) {
 741         ListRecTy *LType = dynamic_cast<ListRecTy*>(LHSt->getType());
 742         StringRecTy *SType = dynamic_cast<StringRecTy*>(LHSt->getType());
 743         if (LType == 0 && SType == 0) {
 744           TokError("expected list or string type argumnet in unary operator");
 745           return 0;
 746         }
 747       }
 748
 749       if (Code == UnOpInit::CAR
 750           || Code == UnOpInit::CDR) {
 751         if (LHSl == 0 && LHSt == 0) {
 752           TokError("expected list type argumnet in unary operator");
 753           return 0;
 754         }
 755
 756         if (LHSl && LHSl->getSize() == 0) {
 757           TokError("empty list argument in unary operator");
 758           return 0;
 759         }
 760         if (LHSl) {
 761           Init *Item = LHSl->getElement(0);
 762           TypedInit *Itemt = dynamic_cast<TypedInit*>(Item);
 763           if (Itemt == 0) {
 764             TokError("untyped list element in unary operator");
 765             return 0;
 766           }
 767           if (Code == UnOpInit::CAR) {
 768             Type = Itemt->getType();
 769           } else {
 770             Type = new ListRecTy(Itemt->getType());
 771           }
 772         } else {
 773           assert(LHSt && "expected list type argument in unary operator");
 774           ListRecTy *LType = dynamic_cast<ListRecTy*>(LHSt->getType());
 775           if (LType == 0) {
 776             TokError("expected list type argumnet in unary operator");
 777             return 0;
 778           }
 779           if (Code == UnOpInit::CAR) {
 780             Type = LType->getElementType();
 781           } else {
 782             Type = LType;
 783           }
 784         }
 785       }
 786     }
 787
 788     if (Lex.getCode() != tgtok::r_paren) {
 789       TokError("expected ')' in unary operator");
 790       return 0;
 791     }
 792     Lex.Lex();  // eat the ')'
 793     return (new UnOpInit(Code, LHS, Type))->Fold(CurRec, CurMultiClass);
 794   }
 795
 796   case tgtok::XConcat:
 797   case tgtok::XSRA:
 798   case tgtok::XSRL:
 799   case tgtok::XSHL:
 800   case tgtok::XEq:
 801   case tgtok::XStrConcat: {  // Value ::= !binop '(' Value ',' Value ')'
 802     tgtok::TokKind OpTok = Lex.getCode();
 803     SMLoc OpLoc = Lex.getLoc();
 804     Lex.Lex();  // eat the operation
 805
 806     BinOpInit::BinaryOp Code;
 807     RecTy *Type = 0;
 808
 809     switch (OpTok) {
 810     default: assert(0 && "Unhandled code!");
 811     case tgtok::XConcat: Code = BinOpInit::CONCAT; Type = new DagRecTy(); break;
 812     case tgtok::XSRA:    Code = BinOpInit::SRA;    Type = new IntRecTy(); break;
 813     case tgtok::XSRL:    Code = BinOpInit::SRL;    Type = new IntRecTy(); break;
 814     case tgtok::XSHL:    Code = BinOpInit::SHL;    Type = new IntRecTy(); break;
 815     case tgtok::XEq:     Code = BinOpInit::EQ;     Type = new BitRecTy(); break;
 816     case tgtok::XStrConcat:
 817       Code = BinOpInit::STRCONCAT;
 818       Type = new StringRecTy();
 819       break;
 820     }
 821
 822     if (Lex.getCode() != tgtok::l_paren) {
 823       TokError("expected '(' after binary operator");
 824       return 0;
 825     }
 826     Lex.Lex();  // eat the '('
 827
 828     SmallVector<Init*, 2> InitList;
 829
 830     InitList.push_back(ParseValue(CurRec));
 831     if (InitList.back() == 0) return 0;
 832
 833     while (Lex.getCode() == tgtok::comma) {
 834       Lex.Lex();  // eat the ','
 835
 836       InitList.push_back(ParseValue(CurRec));
 837       if (InitList.back() == 0) return 0;
 838     }
 839
 840     if (Lex.getCode() != tgtok::r_paren) {
 841       TokError("expected ')' in operator");
 842       return 0;
 843     }
 844     Lex.Lex();  // eat the ')'
 845
 846     // We allow multiple operands to associative operators like !strconcat as
 847     // shorthand for nesting them.
 848     if (Code == BinOpInit::STRCONCAT) {
 849       while (InitList.size() > 2) {
 850         Init *RHS = InitList.pop_back_val();
 851         RHS = (new BinOpInit(Code, InitList.back(), RHS, Type))
 852                       ->Fold(CurRec, CurMultiClass);
 853         InitList.back() = RHS;
 854       }
 855     }
 856
 857     if (InitList.size() == 2)
 858       return (new BinOpInit(Code, InitList[0], InitList[1], Type))
 859         ->Fold(CurRec, CurMultiClass);
 860
 861     Error(OpLoc, "expected two operands to operator");
 862     return 0;
 863   }
 864
 865   case tgtok::XIf:
 866   case tgtok::XForEach:
 867   case tgtok::XSubst: {  // Value ::= !ternop '(' Value ',' Value ',' Value ')'
 868     TernOpInit::TernaryOp Code;
 869     RecTy *Type = 0;
 870
 871
 872     tgtok::TokKind LexCode = Lex.getCode();
 873     Lex.Lex();  // eat the operation
 874     switch (LexCode) {
 875     default: assert(0 && "Unhandled code!");
 876     case tgtok::XIf:
 877       Code = TernOpInit::IF;
 878       break;
 879     case tgtok::XForEach:
 880       Code = TernOpInit::FOREACH;
 881       break;
 882     case tgtok::XSubst:
 883       Code = TernOpInit::SUBST;
 884       break;
 885     }
 886     if (Lex.getCode() != tgtok::l_paren) {
 887       TokError("expected '(' after ternary operator");
 888       return 0;
 889     }
 890     Lex.Lex();  // eat the '('
 891
 892     Init *LHS = ParseValue(CurRec);
 893     if (LHS == 0) return 0;
 894
 895     if (Lex.getCode() != tgtok::comma) {
 896       TokError("expected ',' in ternary operator");
 897       return 0;
 898     }
 899     Lex.Lex();  // eat the ','
 900
 901     Init *MHS = ParseValue(CurRec);
 902     if (MHS == 0) return 0;
 903
 904     if (Lex.getCode() != tgtok::comma) {
 905       TokError("expected ',' in ternary operator");
 906       return 0;
 907     }
 908     Lex.Lex();  // eat the ','
 909
 910     Init *RHS = ParseValue(CurRec);
 911     if (RHS == 0) return 0;
 912
 913     if (Lex.getCode() != tgtok::r_paren) {
 914       TokError("expected ')' in binary operator");
 915       return 0;
 916     }
 917     Lex.Lex();  // eat the ')'
 918
 919     switch (LexCode) {
 920     default: assert(0 && "Unhandled code!");
 921     case tgtok::XIf: {
 922       TypedInit *MHSt = dynamic_cast<TypedInit *>(MHS);
 923       TypedInit *RHSt = dynamic_cast<TypedInit *>(RHS);
 924       if (MHSt == 0 || RHSt == 0) {
 925         TokError("could not get type for !if");
 926         return 0;
 927       }
 928       if (MHSt->getType()->typeIsConvertibleTo(RHSt->getType())) {
 929         Type = RHSt->getType();
 930       } else if (RHSt->getType()->typeIsConvertibleTo(MHSt->getType())) {
 931         Type = MHSt->getType();
 932       } else {
 933         TokError("inconsistent types for !if");
 934         return 0;
 935       }
 936       break;
 937     }
 938     case tgtok::XForEach: {
 939       TypedInit *MHSt = dynamic_cast<TypedInit *>(MHS);
 940       if (MHSt == 0) {
 941         TokError("could not get type for !foreach");
 942         return 0;
 943       }
 944       Type = MHSt->getType();
 945       break;
 946     }
 947     case tgtok::XSubst: {
 948       TypedInit *RHSt = dynamic_cast<TypedInit *>(RHS);
 949       if (RHSt == 0) {
 950         TokError("could not get type for !subst");
 951         return 0;
 952       }
 953       Type = RHSt->getType();
 954       break;
 955     }
 956     }
 957     return (new TernOpInit(Code, LHS, MHS, RHS, Type))->Fold(CurRec,
 958                                                              CurMultiClass);
 959   }
 960   }
 961   TokError("could not parse operation");
 962   return 0;
 963 }
 964
 965 /// ParseOperatorType - Parse a type for an operator.  This returns
 966 /// null on error.
 967 ///
 968 /// OperatorType ::= '<' Type '>'
 969 ///
 970 RecTy *TGParser::ParseOperatorType() {
 971   RecTy *Type = 0;
 972
 973   if (Lex.getCode() != tgtok::less) {
 974     TokError("expected type name for operator");
 975     return 0;
 976   }
 977   Lex.Lex();  // eat the <
 978
 979   Type = ParseType();
 980
 981   if (Type == 0) {
 982     TokError("expected type name for operator");
 983     return 0;
 984   }
 985
 986   if (Lex.getCode() != tgtok::greater) {
 987     TokError("expected type name for operator");
 988     return 0;
 989   }
 990   Lex.Lex();  // eat the >
 991
 992   return Type;
 993 }
 994
 995
 996 /// ParseSimpleValue - Parse a tblgen value.  This returns null on error.
 997 ///
 998 ///   SimpleValue ::= IDValue
 999 ///   SimpleValue ::= INTVAL
1000 ///   SimpleValue ::= STRVAL+
1001 ///   SimpleValue ::= CODEFRAGMENT
1002 ///   SimpleValue ::= '?'
1003 ///   SimpleValue ::= '{' ValueList '}'
1004 ///   SimpleValue ::= ID '<' ValueListNE '>'
1005 ///   SimpleValue ::= '[' ValueList ']'
1006 ///   SimpleValue ::= '(' IDValue DagArgList ')'
1007 ///   SimpleValue ::= CONCATTOK '(' Value ',' Value ')'
1008 ///   SimpleValue ::= SHLTOK '(' Value ',' Value ')'
1009 ///   SimpleValue ::= SRATOK '(' Value ',' Value ')'
1010 ///   SimpleValue ::= SRLTOK '(' Value ',' Value ')'
1011 ///   SimpleValue ::= STRCONCATTOK '(' Value ',' Value ')'
1012 ///
1013 Init *TGParser::ParseSimpleValue(Record *CurRec, RecTy *ItemType) {
1014   Init *R = 0;
1015   switch (Lex.getCode()) {
1016   default: TokError("Unknown token when parsing a value"); break;
1017   case tgtok::IntVal: R = new IntInit(Lex.getCurIntVal()); Lex.Lex(); break;
1018   case tgtok::StrVal: {
1019     std::string Val = Lex.getCurStrVal();
1020     Lex.Lex();
1021
1022     // Handle multiple consecutive concatenated strings.
1023     while (Lex.getCode() == tgtok::StrVal) {
1024       Val += Lex.getCurStrVal();
1025       Lex.Lex();
1026     }
1027
1028     R = new StringInit(Val);
1029     break;
1030   }
1031   case tgtok::CodeFragment:
1032     R = new CodeInit(Lex.getCurStrVal());
1033     Lex.Lex();
1034     break;
1035   case tgtok::question:
1036     R = new UnsetInit();
1037     Lex.Lex();
1038     break;
1039   case tgtok::Id: {
1040     SMLoc NameLoc = Lex.getLoc();
1041     std::string Name = Lex.getCurStrVal();
1042     if (Lex.Lex() != tgtok::less)  // consume the Id.
1043       return ParseIDValue(CurRec, Name, NameLoc);    // Value ::= IDValue
1044
1045     // Value ::= ID '<' ValueListNE '>'
1046     if (Lex.Lex() == tgtok::greater) {
1047       TokError("expected non-empty value list");
1048       return 0;
1049     }
1050
1051     // This is a CLASS<initvalslist> expression.  This is supposed to synthesize
1052     // a new anonymous definition, deriving from CLASS<initvalslist> with no
1053     // body.
1054     Record *Class = Records.getClass(Name);
1055     if (!Class) {
1056       Error(NameLoc, "Expected a class name, got '" + Name + "'");
1057       return 0;
1058     }
1059
1060     std::vector<Init*> ValueList = ParseValueList(CurRec, Class);
1061     if (ValueList.empty()) return 0;
1062
1063     if (Lex.getCode() != tgtok::greater) {
1064       TokError("expected '>' at end of value list");
1065       return 0;
1066     }
1067     Lex.Lex();  // eat the '>'
1068
1069     // Create the new record, set it as CurRec temporarily.
1070     static unsigned AnonCounter = 0;
1071     Record *NewRec = new Record("anonymous.val."+utostr(AnonCounter++),NameLoc);
1072     SubClassReference SCRef;
1073     SCRef.RefLoc = NameLoc;
1074     SCRef.Rec = Class;
1075     SCRef.TemplateArgs = ValueList;
1076     // Add info about the subclass to NewRec.
1077     if (AddSubClass(NewRec, SCRef))
1078       return 0;
1079     NewRec->resolveReferences();
1080     Records.addDef(NewRec);
1081
1082     // The result of the expression is a reference to the new record.
1083     return new DefInit(NewRec);
1084   }
1085   case tgtok::l_brace: {           // Value ::= '{' ValueList '}'
1086     SMLoc BraceLoc = Lex.getLoc();
1087     Lex.Lex(); // eat the '{'
1088     std::vector<Init*> Vals;
1089
1090     if (Lex.getCode() != tgtok::r_brace) {
1091       Vals = ParseValueList(CurRec);
1092       if (Vals.empty()) return 0;
1093     }
1094     if (Lex.getCode() != tgtok::r_brace) {
1095       TokError("expected '}' at end of bit list value");
1096       return 0;
1097     }
1098     Lex.Lex();  // eat the '}'
1099
1100     BitsInit *Result = new BitsInit(Vals.size());
1101     for (unsigned i = 0, e = Vals.size(); i != e; ++i) {
1102       Init *Bit = Vals[i]->convertInitializerTo(new BitRecTy());
1103       if (Bit == 0) {
1104         Error(BraceLoc, "Element #" + utostr(i) + " (" + Vals[i]->getAsString()+
1105               ") is not convertable to a bit");
1106         return 0;
1107       }
1108       Result->setBit(Vals.size()-i-1, Bit);
1109     }
1110     return Result;
1111   }
1112   case tgtok::l_square: {          // Value ::= '[' ValueList ']'
1113     Lex.Lex(); // eat the '['
1114     std::vector<Init*> Vals;
1115
1116     RecTy *DeducedEltTy = 0;
1117     ListRecTy *GivenListTy = 0;
1118
1119     if (ItemType != 0) {
1120       ListRecTy *ListType = dynamic_cast<ListRecTy*>(ItemType);
1121       if (ListType == 0) {
1122         std::stringstream s;
1123         s << "Type mismatch for list, expected list type, got "
1124           << ItemType->getAsString();
1125         TokError(s.str());
1126       }
1127       GivenListTy = ListType;
1128     }
1129
1130     if (Lex.getCode() != tgtok::r_square) {
1131       Vals = ParseValueList(CurRec, 0,
1132                             GivenListTy ? GivenListTy->getElementType() : 0);
1133       if (Vals.empty()) return 0;
1134     }
1135     if (Lex.getCode() != tgtok::r_square) {
1136       TokError("expected ']' at end of list value");
1137       return 0;
1138     }
1139     Lex.Lex();  // eat the ']'
1140
1141     RecTy *GivenEltTy = 0;
1142     if (Lex.getCode() == tgtok::less) {
1143       // Optional list element type
1144       Lex.Lex();  // eat the '<'
1145
1146       GivenEltTy = ParseType();
1147       if (GivenEltTy == 0) {
1148         // Couldn't parse element type
1149         return 0;
1150       }
1151
1152       if (Lex.getCode() != tgtok::greater) {
1153         TokError("expected '>' at end of list element type");
1154         return 0;
1155       }
1156       Lex.Lex();  // eat the '>'
1157     }
1158
1159     // Check elements
1160     RecTy *EltTy = 0;
1161     for (std::vector<Init *>::iterator i = Vals.begin(), ie = Vals.end();
1162          i != ie;
1163          ++i) {
1164       TypedInit *TArg = dynamic_cast<TypedInit*>(*i);
1165       if (TArg == 0) {
1166         TokError("Untyped list element");
1167         return 0;
1168       }
1169       if (EltTy != 0) {
1170         EltTy = resolveTypes(EltTy, TArg->getType());
1171         if (EltTy == 0) {
1172           TokError("Incompatible types in list elements");
1173           return 0;
1174         }
1175       } else {
1176         EltTy = TArg->getType();
1177       }
1178     }
1179
1180     if (GivenEltTy != 0) {
1181       if (EltTy != 0) {
1182         // Verify consistency
1183         if (!EltTy->typeIsConvertibleTo(GivenEltTy)) {
1184           TokError("Incompatible types in list elements");
1185           return 0;
1186         }
1187       }
1188       EltTy = GivenEltTy;
1189     }
1190
1191     if (EltTy == 0) {
1192       if (ItemType == 0) {
1193         TokError("No type for list");
1194         return 0;
1195       }
1196       DeducedEltTy = GivenListTy->getElementType();
1197     } else {
1198       // Make sure the deduced type is compatible with the given type
1199       if (GivenListTy) {
1200         if (!EltTy->typeIsConvertibleTo(GivenListTy->getElementType())) {
1201           TokError("Element type mismatch for list");
1202           return 0;
1203         }
1204       }
1205       DeducedEltTy = EltTy;
1206     }
1207
1208     return new ListInit(Vals, DeducedEltTy);
1209   }
1210   case tgtok::l_paren: {         // Value ::= '(' IDValue DagArgList ')'
1211     Lex.Lex();   // eat the '('
1212     if (Lex.getCode() != tgtok::Id && Lex.getCode() != tgtok::XCast) {
1213       TokError("expected identifier in dag init");
1214       return 0;
1215     }
1216
1217     Init *Operator = ParseValue(CurRec);
1218     if (Operator == 0) return 0;
1219
1220     // If the operator name is present, parse it.
1221     std::string OperatorName;
1222     if (Lex.getCode() == tgtok::colon) {
1223       if (Lex.Lex() != tgtok::VarName) { // eat the ':'
1224         TokError("expected variable name in dag operator");
1225         return 0;
1226       }
1227       OperatorName = Lex.getCurStrVal();
1228       Lex.Lex();  // eat the VarName.
1229     }
1230
1231     std::vector<std::pair<llvm::Init*, std::string> > DagArgs;
1232     if (Lex.getCode() != tgtok::r_paren) {
1233       DagArgs = ParseDagArgList(CurRec);
1234       if (DagArgs.empty()) return 0;
1235     }
1236
1237     if (Lex.getCode() != tgtok::r_paren) {
1238       TokError("expected ')' in dag init");
1239       return 0;
1240     }
1241     Lex.Lex();  // eat the ')'
1242
1243     return new DagInit(Operator, OperatorName, DagArgs);
1244   }
1245
1246   case tgtok::XCar:
1247   case tgtok::XCdr:
1248   case tgtok::XNull:
1249   case tgtok::XCast:  // Value ::= !unop '(' Value ')'
1250   case tgtok::XConcat:
1251   case tgtok::XSRA:
1252   case tgtok::XSRL:
1253   case tgtok::XSHL:
1254   case tgtok::XEq:
1255   case tgtok::XStrConcat:   // Value ::= !binop '(' Value ',' Value ')'
1256   case tgtok::XIf:
1257   case tgtok::XForEach:
1258   case tgtok::XSubst: {  // Value ::= !ternop '(' Value ',' Value ',' Value ')'
1259     return ParseOperation(CurRec);
1260   }
1261   }
1262
1263   return R;
1264 }
1265
1266 /// ParseValue - Parse a tblgen value.  This returns null on error.
1267 ///
1268 ///   Value       ::= SimpleValue ValueSuffix*
1269 ///   ValueSuffix ::= '{' BitList '}'
1270 ///   ValueSuffix ::= '[' BitList ']'
1271 ///   ValueSuffix ::= '.' ID
1272 ///
1273 Init *TGParser::ParseValue(Record *CurRec, RecTy *ItemType) {
1274   Init *Result = ParseSimpleValue(CurRec, ItemType);
1275   if (Result == 0) return 0;
1276
1277   // Parse the suffixes now if present.
1278   while (1) {
1279     switch (Lex.getCode()) {
1280     default: return Result;
1281     case tgtok::l_brace: {
1282       SMLoc CurlyLoc = Lex.getLoc();
1283       Lex.Lex(); // eat the '{'
1284       std::vector<unsigned> Ranges = ParseRangeList();
1285       if (Ranges.empty()) return 0;
1286
1287       // Reverse the bitlist.
1288       std::reverse(Ranges.begin(), Ranges.end());
1289       Result = Result->convertInitializerBitRange(Ranges);
1290       if (Result == 0) {
1291         Error(CurlyLoc, "Invalid bit range for value");
1292         return 0;
1293       }
1294
1295       // Eat the '}'.
1296       if (Lex.getCode() != tgtok::r_brace) {
1297         TokError("expected '}' at end of bit range list");
1298         return 0;
1299       }
1300       Lex.Lex();
1301       break;
1302     }
1303     case tgtok::l_square: {
1304       SMLoc SquareLoc = Lex.getLoc();
1305       Lex.Lex(); // eat the '['
1306       std::vector<unsigned> Ranges = ParseRangeList();
1307       if (Ranges.empty()) return 0;
1308
1309       Result = Result->convertInitListSlice(Ranges);
1310       if (Result == 0) {
1311         Error(SquareLoc, "Invalid range for list slice");
1312         return 0;
1313       }
1314
1315       // Eat the ']'.
1316       if (Lex.getCode() != tgtok::r_square) {
1317         TokError("expected ']' at end of list slice");
1318         return 0;
1319       }
1320       Lex.Lex();
1321       break;
1322     }
1323     case tgtok::period:
1324       if (Lex.Lex() != tgtok::Id) {  // eat the .
1325         TokError("expected field identifier after '.'");
1326         return 0;
1327       }
1328       if (!Result->getFieldType(Lex.getCurStrVal())) {
1329         TokError("Cannot access field '" + Lex.getCurStrVal() + "' of value '" +
1330                  Result->getAsString() + "'");
1331         return 0;
1332       }
1333       Result = new FieldInit(Result, Lex.getCurStrVal());
1334       Lex.Lex();  // eat field name
1335       break;
1336     }
1337   }
1338 }
1339
1340 /// ParseDagArgList - Parse the argument list for a dag literal expression.
1341 ///
1342 ///    ParseDagArgList ::= Value (':' VARNAME)?
1343 ///    ParseDagArgList ::= ParseDagArgList ',' Value (':' VARNAME)?
1344 std::vector<std::pair<llvm::Init*, std::string> >
1345 TGParser::ParseDagArgList(Record *CurRec) {
1346   std::vector<std::pair<llvm::Init*, std::string> > Result;
1347
1348   while (1) {
1349     Init *Val = ParseValue(CurRec);
1350     if (Val == 0) return std::vector<std::pair<llvm::Init*, std::string> >();
1351
1352     // If the variable name is present, add it.
1353     std::string VarName;
1354     if (Lex.getCode() == tgtok::colon) {
1355       if (Lex.Lex() != tgtok::VarName) { // eat the ':'
1356         TokError("expected variable name in dag literal");
1357         return std::vector<std::pair<llvm::Init*, std::string> >();
1358       }
1359       VarName = Lex.getCurStrVal();
1360       Lex.Lex();  // eat the VarName.
1361     }
1362
1363     Result.push_back(std::make_pair(Val, VarName));
1364
1365     if (Lex.getCode() != tgtok::comma) break;
1366     Lex.Lex(); // eat the ','
1367   }
1368
1369   return Result;
1370 }
1371
1372
1373 /// ParseValueList - Parse a comma separated list of values, returning them as a
1374 /// vector.  Note that this always expects to be able to parse at least one
1375 /// value.  It returns an empty list if this is not possible.
1376 ///
1377 ///   ValueList ::= Value (',' Value)
1378 ///
1379 std::vector<Init*> TGParser::ParseValueList(Record *CurRec, Record *ArgsRec,
1380                                             RecTy *EltTy) {
1381   std::vector<Init*> Result;
1382   RecTy *ItemType = EltTy;
1383   unsigned int ArgN = 0;
1384   if (ArgsRec != 0 && EltTy == 0) {
1385     const std::vector<std::string> &TArgs = ArgsRec->getTemplateArgs();
1386     const RecordVal *RV = ArgsRec->getValue(TArgs[ArgN]);
1387     assert(RV && "Template argument record not found??");
1388     ItemType = RV->getType();
1389     ++ArgN;
1390   }
1391   Result.push_back(ParseValue(CurRec, ItemType));
1392   if (Result.back() == 0) return std::vector<Init*>();
1393
1394   while (Lex.getCode() == tgtok::comma) {
1395     Lex.Lex();  // Eat the comma
1396
1397     if (ArgsRec != 0 && EltTy == 0) {
1398       const std::vector<std::string> &TArgs = ArgsRec->getTemplateArgs();
1399       if (ArgN >= TArgs.size()) {
1400         TokError("too many template arguments");
1401         return std::vector<Init*>();
1402       }
1403       const RecordVal *RV = ArgsRec->getValue(TArgs[ArgN]);
1404       assert(RV && "Template argument record not found??");
1405       ItemType = RV->getType();
1406       ++ArgN;
1407     }
1408     Result.push_back(ParseValue(CurRec, ItemType));
1409     if (Result.back() == 0) return std::vector<Init*>();
1410   }
1411
1412   return Result;
1413 }
1414
1415
1416 /// ParseDeclaration - Read a declaration, returning the name of field ID, or an
1417 /// empty string on error.  This can happen in a number of different context's,
1418 /// including within a def or in the template args for a def (which which case
1419 /// CurRec will be non-null) and within the template args for a multiclass (in
1420 /// which case CurRec will be null, but CurMultiClass will be set).  This can
1421 /// also happen within a def that is within a multiclass, which will set both
1422 /// CurRec and CurMultiClass.
1423 ///
1424 ///  Declaration ::= FIELD? Type ID ('=' Value)?
1425 ///
1426 std::string TGParser::ParseDeclaration(Record *CurRec,
1427                                        bool ParsingTemplateArgs) {
1428   // Read the field prefix if present.
1429   bool HasField = Lex.getCode() == tgtok::Field;
1430   if (HasField) Lex.Lex();
1431
1432   RecTy *Type = ParseType();
1433   if (Type == 0) return "";
1434
1435   if (Lex.getCode() != tgtok::Id) {
1436     TokError("Expected identifier in declaration");
1437     return "";
1438   }
1439
1440   SMLoc IdLoc = Lex.getLoc();
1441   std::string DeclName = Lex.getCurStrVal();
1442   Lex.Lex();
1443
1444   if (ParsingTemplateArgs) {
1445     if (CurRec) {
1446       DeclName = CurRec->getName() + ":" + DeclName;
1447     } else {
1448       assert(CurMultiClass);
1449     }
1450     if (CurMultiClass)
1451       DeclName = CurMultiClass->Rec.getName() + "::" + DeclName;
1452   }
1453
1454   // Add the value.
1455   if (AddValue(CurRec, IdLoc, RecordVal(DeclName, Type, HasField)))
1456     return "";
1457
1458   // If a value is present, parse it.
1459   if (Lex.getCode() == tgtok::equal) {
1460     Lex.Lex();
1461     SMLoc ValLoc = Lex.getLoc();
1462     Init *Val = ParseValue(CurRec, Type);
1463     if (Val == 0 ||
1464         SetValue(CurRec, ValLoc, DeclName, std::vector<unsigned>(), Val))
1465       return "";
1466   }
1467
1468   return DeclName;
1469 }
1470
1471 /// ParseTemplateArgList - Read a template argument list, which is a non-empty
1472 /// sequence of template-declarations in <>'s.  If CurRec is non-null, these are
1473 /// template args for a def, which may or may not be in a multiclass.  If null,
1474 /// these are the template args for a multiclass.
1475 ///
1476 ///    TemplateArgList ::= '<' Declaration (',' Declaration)* '>'
1477 ///
1478 bool TGParser::ParseTemplateArgList(Record *CurRec) {
1479   assert(Lex.getCode() == tgtok::less && "Not a template arg list!");
1480   Lex.Lex(); // eat the '<'
1481
1482   Record *TheRecToAddTo = CurRec ? CurRec : &CurMultiClass->Rec;
1483
1484   // Read the first declaration.
1485   std::string TemplArg = ParseDeclaration(CurRec, true/*templateargs*/);
1486   if (TemplArg.empty())
1487     return true;
1488
1489   TheRecToAddTo->addTemplateArg(TemplArg);
1490
1491   while (Lex.getCode() == tgtok::comma) {
1492     Lex.Lex(); // eat the ','
1493
1494     // Read the following declarations.
1495     TemplArg = ParseDeclaration(CurRec, true/*templateargs*/);
1496     if (TemplArg.empty())
1497       return true;
1498     TheRecToAddTo->addTemplateArg(TemplArg);
1499   }
1500
1501   if (Lex.getCode() != tgtok::greater)
1502     return TokError("expected '>' at end of template argument list");
1503   Lex.Lex(); // eat the '>'.
1504   return false;
1505 }
1506
1507
1508 /// ParseBodyItem - Parse a single item at within the body of a def or class.
1509 ///
1510 ///   BodyItem ::= Declaration ';'
1511 ///   BodyItem ::= LET ID OptionalBitList '=' Value ';'
1512 bool TGParser::ParseBodyItem(Record *CurRec) {
1513   if (Lex.getCode() != tgtok::Let) {
1514     if (ParseDeclaration(CurRec, false).empty())
1515       return true;
1516
1517     if (Lex.getCode() != tgtok::semi)
1518       return TokError("expected ';' after declaration");
1519     Lex.Lex();
1520     return false;
1521   }
1522
1523   // LET ID OptionalRangeList '=' Value ';'
1524   if (Lex.Lex() != tgtok::Id)
1525     return TokError("expected field identifier after let");
1526
1527   SMLoc IdLoc = Lex.getLoc();
1528   std::string FieldName = Lex.getCurStrVal();
1529   Lex.Lex();  // eat the field name.
1530
1531   std::vector<unsigned> BitList;
1532   if (ParseOptionalBitList(BitList))
1533     return true;
1534   std::reverse(BitList.begin(), BitList.end());
1535
1536   if (Lex.getCode() != tgtok::equal)
1537     return TokError("expected '=' in let expression");
1538   Lex.Lex();  // eat the '='.
1539
1540   RecordVal *Field = CurRec->getValue(FieldName);
1541   if (Field == 0)
1542     return TokError("Value '" + FieldName + "' unknown!");
1543
1544   RecTy *Type = Field->getType();
1545
1546   Init *Val = ParseValue(CurRec, Type);
1547   if (Val == 0) return true;
1548
1549   if (Lex.getCode() != tgtok::semi)
1550     return TokError("expected ';' after let expression");
1551   Lex.Lex();
1552
1553   return SetValue(CurRec, IdLoc, FieldName, BitList, Val);
1554 }
1555
1556 /// ParseBody - Read the body of a class or def.  Return true on error, false on
1557 /// success.
1558 ///
1559 ///   Body     ::= ';'
1560 ///   Body     ::= '{' BodyList '}'
1561 ///   BodyList BodyItem*
1562 ///
1563 bool TGParser::ParseBody(Record *CurRec) {
1564   // If this is a null definition, just eat the semi and return.
1565   if (Lex.getCode() == tgtok::semi) {
1566     Lex.Lex();
1567     return false;
1568   }
1569
1570   if (Lex.getCode() != tgtok::l_brace)
1571     return TokError("Expected ';' or '{' to start body");
1572   // Eat the '{'.
1573   Lex.Lex();
1574
1575   while (Lex.getCode() != tgtok::r_brace)
1576     if (ParseBodyItem(CurRec))
1577       return true;
1578
1579   // Eat the '}'.
1580   Lex.Lex();
1581   return false;
1582 }
1583
1584 /// ParseObjectBody - Parse the body of a def or class.  This consists of an
1585 /// optional ClassList followed by a Body.  CurRec is the current def or class
1586 /// that is being parsed.
1587 ///
1588 ///   ObjectBody      ::= BaseClassList Body
1589 ///   BaseClassList   ::= /*empty*/
1590 ///   BaseClassList   ::= ':' BaseClassListNE
1591 ///   BaseClassListNE ::= SubClassRef (',' SubClassRef)*
1592 ///
1593 bool TGParser::ParseObjectBody(Record *CurRec) {
1594   // If there is a baseclass list, read it.
1595   if (Lex.getCode() == tgtok::colon) {
1596     Lex.Lex();
1597
1598     // Read all of the subclasses.
1599     SubClassReference SubClass = ParseSubClassReference(CurRec, false);
1600     while (1) {
1601       // Check for error.
1602       if (SubClass.Rec == 0) return true;
1603
1604       // Add it.
1605       if (AddSubClass(CurRec, SubClass))
1606         return true;
1607
1608       if (Lex.getCode() != tgtok::comma) break;
1609       Lex.Lex(); // eat ','.
1610       SubClass = ParseSubClassReference(CurRec, false);
1611     }
1612   }
1613
1614   // Process any variables on the let stack.
1615   for (unsigned i = 0, e = LetStack.size(); i != e; ++i)
1616     for (unsigned j = 0, e = LetStack[i].size(); j != e; ++j)
1617       if (SetValue(CurRec, LetStack[i][j].Loc, LetStack[i][j].Name,
1618                    LetStack[i][j].Bits, LetStack[i][j].Value))
1619         return true;
1620
1621   return ParseBody(CurRec);
1622 }
1623
1624 /// ParseDef - Parse and return a top level or multiclass def, return the record
1625 /// corresponding to it.  This returns null on error.
1626 ///
1627 ///   DefInst ::= DEF ObjectName ObjectBody
1628 ///
1629 bool TGParser::ParseDef(MultiClass *CurMultiClass) {
1630   SMLoc DefLoc = Lex.getLoc();
1631   assert(Lex.getCode() == tgtok::Def && "Unknown tok");
1632   Lex.Lex();  // Eat the 'def' token.
1633
1634   // Parse ObjectName and make a record for it.
1635   Record *CurRec = new Record(ParseObjectName(), DefLoc);
1636
1637   if (!CurMultiClass) {
1638     // Top-level def definition.
1639
1640     // Ensure redefinition doesn't happen.
1641     if (Records.getDef(CurRec->getName())) {
1642       Error(DefLoc, "def '" + CurRec->getName() + "' already defined");
1643       return true;
1644     }
1645     Records.addDef(CurRec);
1646   } else {
1647     // Otherwise, a def inside a multiclass, add it to the multiclass.
1648     for (unsigned i = 0, e = CurMultiClass->DefPrototypes.size(); i != e; ++i)
1649       if (CurMultiClass->DefPrototypes[i]->getName() == CurRec->getName()) {
1650         Error(DefLoc, "def '" + CurRec->getName() +
1651               "' already defined in this multiclass!");
1652         return true;
1653       }
1654     CurMultiClass->DefPrototypes.push_back(CurRec);
1655   }
1656
1657   if (ParseObjectBody(CurRec))
1658     return true;
1659
1660   if (CurMultiClass == 0)  // Def's in multiclasses aren't really defs.
1661     CurRec->resolveReferences();
1662
1663   // If ObjectBody has template arguments, it's an error.
1664   assert(CurRec->getTemplateArgs().empty() && "How'd this get template args?");
1665
1666   if (CurMultiClass) {
1667     // Copy the template arguments for the multiclass into the def.
1668     const std::vector<std::string> &TArgs =
1669                                 CurMultiClass->Rec.getTemplateArgs();
1670
1671     for (unsigned i = 0, e = TArgs.size(); i != e; ++i) {
1672       const RecordVal *RV = CurMultiClass->Rec.getValue(TArgs[i]);
1673       assert(RV && "Template arg doesn't exist?");
1674       CurRec->addValue(*RV);
1675     }
1676   }
1677
1678   return false;
1679 }
1680
1681
1682 /// ParseClass - Parse a tblgen class definition.
1683 ///
1684 ///   ClassInst ::= CLASS ID TemplateArgList? ObjectBody
1685 ///
1686 bool TGParser::ParseClass() {
1687   assert(Lex.getCode() == tgtok::Class && "Unexpected token!");
1688   Lex.Lex();
1689
1690   if (Lex.getCode() != tgtok::Id)
1691     return TokError("expected class name after 'class' keyword");
1692
1693   Record *CurRec = Records.getClass(Lex.getCurStrVal());
1694   if (CurRec) {
1695     // If the body was previously defined, this is an error.
1696     if (!CurRec->getValues().empty() ||
1697         !CurRec->getSuperClasses().empty() ||
1698         !CurRec->getTemplateArgs().empty())
1699       return TokError("Class '" + CurRec->getName() + "' already defined");
1700   } else {
1701     // If this is the first reference to this class, create and add it.
1702     CurRec = new Record(Lex.getCurStrVal(), Lex.getLoc());
1703     Records.addClass(CurRec);
1704   }
1705   Lex.Lex(); // eat the name.
1706
1707   // If there are template args, parse them.
1708   if (Lex.getCode() == tgtok::less)
1709     if (ParseTemplateArgList(CurRec))
1710       return true;
1711
1712   // Finally, parse the object body.
1713   return ParseObjectBody(CurRec);
1714 }
1715
1716 /// ParseLetList - Parse a non-empty list of assignment expressions into a list
1717 /// of LetRecords.
1718 ///
1719 ///   LetList ::= LetItem (',' LetItem)*
1720 ///   LetItem ::= ID OptionalRangeList '=' Value
1721 ///
1722 std::vector<LetRecord> TGParser::ParseLetList() {
1723   std::vector<LetRecord> Result;
1724
1725   while (1) {
1726     if (Lex.getCode() != tgtok::Id) {
1727       TokError("expected identifier in let definition");
1728       return std::vector<LetRecord>();
1729     }
1730     std::string Name = Lex.getCurStrVal();
1731     SMLoc NameLoc = Lex.getLoc();
1732     Lex.Lex();  // Eat the identifier.
1733
1734     // Check for an optional RangeList.
1735     std::vector<unsigned> Bits;
1736     if (ParseOptionalRangeList(Bits))
1737       return std::vector<LetRecord>();
1738     std::reverse(Bits.begin(), Bits.end());
1739
1740     if (Lex.getCode() != tgtok::equal) {
1741       TokError("expected '=' in let expression");
1742       return std::vector<LetRecord>();
1743     }
1744     Lex.Lex();  // eat the '='.
1745
1746     Init *Val = ParseValue(0);
1747     if (Val == 0) return std::vector<LetRecord>();
1748
1749     // Now that we have everything, add the record.
1750     Result.push_back(LetRecord(Name, Bits, Val, NameLoc));
1751
1752     if (Lex.getCode() != tgtok::comma)
1753       return Result;
1754     Lex.Lex();  // eat the comma.
1755   }
1756 }
1757
1758 /// ParseTopLevelLet - Parse a 'let' at top level.  This can be a couple of
1759 /// different related productions. This works inside multiclasses too.
1760 ///
1761 ///   Object ::= LET LetList IN '{' ObjectList '}'
1762 ///   Object ::= LET LetList IN Object
1763 ///
1764 bool TGParser::ParseTopLevelLet(MultiClass *CurMultiClass) {
1765   assert(Lex.getCode() == tgtok::Let && "Unexpected token");
1766   Lex.Lex();
1767
1768   // Add this entry to the let stack.
1769   std::vector<LetRecord> LetInfo = ParseLetList();
1770   if (LetInfo.empty()) return true;
1771   LetStack.push_back(LetInfo);
1772
1773   if (Lex.getCode() != tgtok::In)
1774     return TokError("expected 'in' at end of top-level 'let'");
1775   Lex.Lex();
1776
1777   // If this is a scalar let, just handle it now
1778   if (Lex.getCode() != tgtok::l_brace) {
1779     // LET LetList IN Object
1780     if (ParseObject(CurMultiClass))
1781       return true;
1782   } else {   // Object ::= LETCommand '{' ObjectList '}'
1783     SMLoc BraceLoc = Lex.getLoc();
1784     // Otherwise, this is a group let.
1785     Lex.Lex();  // eat the '{'.
1786
1787     // Parse the object list.
1788     if (ParseObjectList(CurMultiClass))
1789       return true;
1790
1791     if (Lex.getCode() != tgtok::r_brace) {
1792       TokError("expected '}' at end of top level let command");
1793       return Error(BraceLoc, "to match this '{'");
1794     }
1795     Lex.Lex();
1796   }
1797
1798   // Outside this let scope, this let block is not active.
1799   LetStack.pop_back();
1800   return false;
1801 }
1802
1803 /// ParseMultiClass - Parse a multiclass definition.
1804 ///
1805 ///  MultiClassInst ::= MULTICLASS ID TemplateArgList?
1806 ///                     ':' BaseMultiClassList '{' MultiClassDef+ '}'
1807 ///
1808 bool TGParser::ParseMultiClass() {
1809   assert(Lex.getCode() == tgtok::MultiClass && "Unexpected token");
1810   Lex.Lex();  // Eat the multiclass token.
1811
1812   if (Lex.getCode() != tgtok::Id)
1813     return TokError("expected identifier after multiclass for name");
1814   std::string Name = Lex.getCurStrVal();
1815
1816   if (MultiClasses.count(Name))
1817     return TokError("multiclass '" + Name + "' already defined");
1818
1819   CurMultiClass = MultiClasses[Name] = new MultiClass(Name, Lex.getLoc());
1820   Lex.Lex();  // Eat the identifier.
1821
1822   // If there are template args, parse them.
1823   if (Lex.getCode() == tgtok::less)
1824     if (ParseTemplateArgList(0))
1825       return true;
1826
1827   bool inherits = false;
1828
1829   // If there are submulticlasses, parse them.
1830   if (Lex.getCode() == tgtok::colon) {
1831     inherits = true;
1832
1833     Lex.Lex();
1834
1835     // Read all of the submulticlasses.
1836     SubMultiClassReference SubMultiClass =
1837       ParseSubMultiClassReference(CurMultiClass);
1838     while (1) {
1839       // Check for error.
1840       if (SubMultiClass.MC == 0) return true;
1841
1842       // Add it.
1843       if (AddSubMultiClass(CurMultiClass, SubMultiClass))
1844         return true;
1845
1846       if (Lex.getCode() != tgtok::comma) break;
1847       Lex.Lex(); // eat ','.
1848       SubMultiClass = ParseSubMultiClassReference(CurMultiClass);
1849     }
1850   }
1851
1852   if (Lex.getCode() != tgtok::l_brace) {
1853     if (!inherits)
1854       return TokError("expected '{' in multiclass definition");
1855     else if (Lex.getCode() != tgtok::semi)
1856       return TokError("expected ';' in multiclass definition");
1857     else
1858       Lex.Lex();  // eat the ';'.
1859   } else {
1860     if (Lex.Lex() == tgtok::r_brace)  // eat the '{'.
1861       return TokError("multiclass must contain at least one def");
1862
1863     while (Lex.getCode() != tgtok::r_brace) {
1864       switch (Lex.getCode()) {
1865         default:
1866           return TokError("expected 'let', 'def' or 'defm' in multiclass body");
1867         case tgtok::Let:
1868         case tgtok::Def:
1869         case tgtok::Defm:
1870           if (ParseObject(CurMultiClass))
1871             return true;
1872          break;
1873       }
1874     }
1875     Lex.Lex();  // eat the '}'.
1876   }
1877
1878   CurMultiClass = 0;
1879   return false;
1880 }
1881
1882 /// ParseDefm - Parse the instantiation of a multiclass.
1883 ///
1884 ///   DefMInst ::= DEFM ID ':' DefmSubClassRef ';'
1885 ///
1886 bool TGParser::ParseDefm(MultiClass *CurMultiClass) {
1887   assert(Lex.getCode() == tgtok::Defm && "Unexpected token!");
1888
1889   std::string DefmPrefix;
1890   if (Lex.Lex() == tgtok::Id) {  // eat the defm.
1891     DefmPrefix = Lex.getCurStrVal();
1892     Lex.Lex();  // Eat the defm prefix.
1893   }
1894
1895   SMLoc DefmPrefixLoc = Lex.getLoc();
1896   if (Lex.getCode() != tgtok::colon)
1897     return TokError("expected ':' after defm identifier");
1898
1899   // Keep track of the new generated record definitions.
1900   std::vector<Record*> NewRecDefs;
1901
1902   // This record also inherits from a regular class (non-multiclass)?
1903   bool InheritFromClass = false;
1904
1905   // eat the colon.
1906   Lex.Lex();
1907
1908   SMLoc SubClassLoc = Lex.getLoc();
1909   SubClassReference Ref = ParseSubClassReference(0, true);
1910
1911   while (1) {
1912     if (Ref.Rec == 0) return true;
1913
1914     // To instantiate a multiclass, we need to first get the multiclass, then
1915     // instantiate each def contained in the multiclass with the SubClassRef
1916     // template parameters.
1917     MultiClass *MC = MultiClasses[Ref.Rec->getName()];
1918     assert(MC && "Didn't lookup multiclass correctly?");
1919     std::vector<Init*> &TemplateVals = Ref.TemplateArgs;
1920
1921     // Verify that the correct number of template arguments were specified.
1922     const std::vector<std::string> &TArgs = MC->Rec.getTemplateArgs();
1923     if (TArgs.size() < TemplateVals.size())
1924       return Error(SubClassLoc,
1925                    "more template args specified than multiclass expects");
1926
1927     // Loop over all the def's in the multiclass, instantiating each one.
1928     for (unsigned i = 0, e = MC->DefPrototypes.size(); i != e; ++i) {
1929       Record *DefProto = MC->DefPrototypes[i];
1930
1931       // Add in the defm name.  If the defm prefix is empty, give each
1932       // instantiated def a unique name.  Otherwise, if "#NAME#" exists in the
1933       // name, substitute the prefix for #NAME#.  Otherwise, use the defm name
1934       // as a prefix.
1935       std::string DefName = DefProto->getName();
1936       if (DefmPrefix.empty()) {
1937         DefName = GetNewAnonymousName();
1938       } else {
1939         std::string::size_type idx = DefName.find("#NAME#");
1940         if (idx != std::string::npos) {
1941           DefName.replace(idx, 6, DefmPrefix);
1942         } else {
1943           // Add the suffix to the defm name to get the new name.
1944           DefName = DefmPrefix + DefName;
1945         }
1946       }
1947
1948       Record *CurRec = new Record(DefName, DefmPrefixLoc);
1949
1950       SubClassReference Ref;
1951       Ref.RefLoc = DefmPrefixLoc;
1952       Ref.Rec = DefProto;
1953       AddSubClass(CurRec, Ref);
1954
1955       // Loop over all of the template arguments, setting them to the specified
1956       // value or leaving them as the default if necessary.
1957       for (unsigned i = 0, e = TArgs.size(); i != e; ++i) {
1958         // Check if a value is specified for this temp-arg.
1959         if (i < TemplateVals.size()) {
1960           // Set it now.
1961           if (SetValue(CurRec, DefmPrefixLoc, TArgs[i], std::vector<unsigned>(),
1962                        TemplateVals[i]))
1963             return true;
1964
1965           // Resolve it next.
1966           CurRec->resolveReferencesTo(CurRec->getValue(TArgs[i]));
1967
1968           // Now remove it.
1969           CurRec->removeValue(TArgs[i]);
1970
1971         } else if (!CurRec->getValue(TArgs[i])->getValue()->isComplete()) {
1972           return Error(SubClassLoc,
1973                        "value not specified for template argument #"+
1974                        utostr(i) + " (" + TArgs[i] + ") of multiclassclass '" +
1975                        MC->Rec.getName() + "'");
1976         }
1977       }
1978
1979       // If the mdef is inside a 'let' expression, add to each def.
1980       for (unsigned i = 0, e = LetStack.size(); i != e; ++i)
1981         for (unsigned j = 0, e = LetStack[i].size(); j != e; ++j)
1982           if (SetValue(CurRec, LetStack[i][j].Loc, LetStack[i][j].Name,
1983                        LetStack[i][j].Bits, LetStack[i][j].Value)) {
1984             Error(DefmPrefixLoc, "when instantiating this defm");
1985             return true;
1986           }
1987
1988       // Ensure redefinition doesn't happen.
1989       if (Records.getDef(CurRec->getName()))
1990         return Error(DefmPrefixLoc, "def '" + CurRec->getName() +
1991                      "' already defined, instantiating defm with subdef '" +
1992                      DefProto->getName() + "'");
1993
1994       // Don't create a top level definition for defm inside multiclasses,
1995       // instead, only update the prototypes and bind the template args
1996       // with the new created definition.
1997       if (CurMultiClass) {
1998         for (unsigned i = 0, e = CurMultiClass->DefPrototypes.size();
1999              i != e; ++i) {
2000           if (CurMultiClass->DefPrototypes[i]->getName() == CurRec->getName()) {
2001             Error(DefmPrefixLoc, "defm '" + CurRec->getName() +
2002                   "' already defined in this multiclass!");
2003             return 0;
2004           }
2005         }
2006         CurMultiClass->DefPrototypes.push_back(CurRec);
2007
2008         // Copy the template arguments for the multiclass into the new def.
2009         const std::vector<std::string> &TA =
2010           CurMultiClass->Rec.getTemplateArgs();
2011
2012         for (unsigned i = 0, e = TA.size(); i != e; ++i) {
2013           const RecordVal *RV = CurMultiClass->Rec.getValue(TA[i]);
2014           assert(RV && "Template arg doesn't exist?");
2015           CurRec->addValue(*RV);
2016         }
2017       } else {
2018         Records.addDef(CurRec);
2019       }
2020
2021       NewRecDefs.push_back(CurRec);
2022     }
2023
2024     if (Lex.getCode() != tgtok::comma) break;
2025     Lex.Lex(); // eat ','.
2026
2027     SubClassLoc = Lex.getLoc();
2028
2029     // A defm can inherit from regular classes (non-multiclass) as
2030     // long as they come in the end of the inheritance list.
2031     InheritFromClass = (Records.getClass(Lex.getCurStrVal()) != 0);
2032
2033     if (InheritFromClass)
2034       break;
2035
2036     Ref = ParseSubClassReference(0, true);
2037   }
2038
2039   if (InheritFromClass) {
2040     // Process all the classes to inherit as if they were part of a
2041     // regular 'def' and inherit all record values.
2042     SubClassReference SubClass = ParseSubClassReference(0, false);
2043     while (1) {
2044       // Check for error.
2045       if (SubClass.Rec == 0) return true;
2046
2047       // Get the expanded definition prototypes and teach them about
2048       // the record values the current class to inherit has
2049       for (unsigned i = 0, e = NewRecDefs.size(); i != e; ++i) {
2050         Record *CurRec = NewRecDefs[i];
2051
2052         // Add it.
2053         if (AddSubClass(CurRec, SubClass))
2054           return true;
2055
2056         // Process any variables on the let stack.
2057         for (unsigned i = 0, e = LetStack.size(); i != e; ++i)
2058           for (unsigned j = 0, e = LetStack[i].size(); j != e; ++j)
2059             if (SetValue(CurRec, LetStack[i][j].Loc, LetStack[i][j].Name,
2060                          LetStack[i][j].Bits, LetStack[i][j].Value))
2061               return true;
2062       }
2063
2064       if (Lex.getCode() != tgtok::comma) break;
2065       Lex.Lex(); // eat ','.
2066       SubClass = ParseSubClassReference(0, false);
2067     }
2068   }
2069
2070   if (!CurMultiClass)
2071     for (unsigned i = 0, e = NewRecDefs.size(); i != e; ++i)
2072       NewRecDefs[i]->resolveReferences();
2073
2074   if (Lex.getCode() != tgtok::semi)
2075     return TokError("expected ';' at end of defm");
2076   Lex.Lex();
2077
2078   return false;
2079 }
2080
2081 /// ParseObject
2082 ///   Object ::= ClassInst
2083 ///   Object ::= DefInst
2084 ///   Object ::= MultiClassInst
2085 ///   Object ::= DefMInst
2086 ///   Object ::= LETCommand '{' ObjectList '}'
2087 ///   Object ::= LETCommand Object
2088 bool TGParser::ParseObject(MultiClass *MC) {
2089   switch (Lex.getCode()) {
2090   default:
2091     return TokError("Expected class, def, defm, multiclass or let definition");
2092   case tgtok::Let:   return ParseTopLevelLet(MC);
2093   case tgtok::Def:   return ParseDef(MC);
2094   case tgtok::Defm:  return ParseDefm(MC);
2095   case tgtok::Class: return ParseClass();
2096   case tgtok::MultiClass: return ParseMultiClass();
2097   }
2098 }
2099
2100 /// ParseObjectList
2101 ///   ObjectList :== Object*
2102 bool TGParser::ParseObjectList(MultiClass *MC) {
2103   while (isObjectStart(Lex.getCode())) {
2104     if (ParseObject(MC))
2105       return true;
2106   }
2107   return false;
2108 }
2109
2110 bool TGParser::ParseFile() {
2111   Lex.Lex(); // Prime the lexer.
2112   if (ParseObjectList()) return true;
2113
2114   // If we have unread input at the end of the file, report it.
2115   if (Lex.getCode() == tgtok::Eof)
2116     return false;
2117
2118   return TokError("Unexpected input at top level");
2119 }
2120