lib/MC/MCParser/AsmParser.cpp

   1 //===- AsmParser.cpp - Parser for Assembly 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 // This class implements the parser for assembly files.
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #include "llvm/ADT/APFloat.h"
  15 #include "llvm/ADT/SmallString.h"
  16 #include "llvm/ADT/StringMap.h"
  17 #include "llvm/ADT/StringSwitch.h"
  18 #include "llvm/ADT/Twine.h"
  19 #include "llvm/MC/MCAsmInfo.h"
  20 #include "llvm/MC/MCContext.h"
  21 #include "llvm/MC/MCExpr.h"
  22 #include "llvm/MC/MCParser/AsmCond.h"
  23 #include "llvm/MC/MCParser/AsmLexer.h"
  24 #include "llvm/MC/MCParser/MCAsmParser.h"
  25 #include "llvm/MC/MCParser/MCParsedAsmOperand.h"
  26 #include "llvm/MC/MCSectionMachO.h"
  27 #include "llvm/MC/MCStreamer.h"
  28 #include "llvm/MC/MCSymbol.h"
  29 #include "llvm/MC/MCDwarf.h"
  30 #include "llvm/Support/CommandLine.h"
  31 #include "llvm/Support/MathExtras.h"
  32 #include "llvm/Support/MemoryBuffer.h"
  33 #include "llvm/Support/SourceMgr.h"
  34 #include "llvm/Support/raw_ostream.h"
  35 #include "llvm/Target/TargetAsmInfo.h"
  36 #include "llvm/Target/TargetAsmParser.h"
  37 #include <cctype>
  38 #include <vector>
  39 using namespace llvm;
  40
  41 static cl::opt<bool>
  42 FatalAssemblerWarnings("fatal-assembler-warnings",
  43                        cl::desc("Consider warnings as error"));
  44
  45 namespace {
  46
  47 /// \brief Helper class for tracking macro definitions.
  48 struct Macro {
  49   StringRef Name;
  50   StringRef Body;
  51   std::vector<StringRef> Parameters;
  52
  53 public:
  54   Macro(StringRef N, StringRef B, const std::vector<StringRef> &P) :
  55     Name(N), Body(B), Parameters(P) {}
  56 };
  57
  58 /// \brief Helper class for storing information about an active macro
  59 /// instantiation.
  60 struct MacroInstantiation {
  61   /// The macro being instantiated.
  62   const Macro *TheMacro;
  63
  64   /// The macro instantiation with substitutions.
  65   MemoryBuffer *Instantiation;
  66
  67   /// The location of the instantiation.
  68   SMLoc InstantiationLoc;
  69
  70   /// The location where parsing should resume upon instantiation completion.
  71   SMLoc ExitLoc;
  72
  73 public:
  74   MacroInstantiation(const Macro *M, SMLoc IL, SMLoc EL,
  75                      MemoryBuffer *I);
  76 };
  77
  78 /// \brief The concrete assembly parser instance.
  79 class AsmParser : public MCAsmParser {
  80   friend class GenericAsmParser;
  81
  82   AsmParser(const AsmParser &);   // DO NOT IMPLEMENT
  83   void operator=(const AsmParser &);  // DO NOT IMPLEMENT
  84 private:
  85   AsmLexer Lexer;
  86   MCContext &Ctx;
  87   MCStreamer &Out;
  88   const MCAsmInfo &MAI;
  89   SourceMgr &SrcMgr;
  90   MCAsmParserExtension *GenericParser;
  91   MCAsmParserExtension *PlatformParser;
  92
  93   /// This is the current buffer index we're lexing from as managed by the
  94   /// SourceMgr object.
  95   int CurBuffer;
  96
  97   AsmCond TheCondState;
  98   std::vector<AsmCond> TheCondStack;
  99
 100   /// DirectiveMap - This is a table handlers for directives.  Each handler is
 101   /// invoked after the directive identifier is read and is responsible for
 102   /// parsing and validating the rest of the directive.  The handler is passed
 103   /// in the directive name and the location of the directive keyword.
 104   StringMap<std::pair<MCAsmParserExtension*, DirectiveHandler> > DirectiveMap;
 105
 106   /// MacroMap - Map of currently defined macros.
 107   StringMap<Macro*> MacroMap;
 108
 109   /// ActiveMacros - Stack of active macro instantiations.
 110   std::vector<MacroInstantiation*> ActiveMacros;
 111
 112   /// Boolean tracking whether macro substitution is enabled.
 113   unsigned MacrosEnabled : 1;
 114
 115   /// Flag tracking whether any errors have been encountered.
 116   unsigned HadError : 1;
 117
 118 public:
 119   AsmParser(const Target &T, SourceMgr &SM, MCContext &Ctx, MCStreamer &Out,
 120             const MCAsmInfo &MAI);
 121   ~AsmParser();
 122
 123   virtual bool Run(bool NoInitialTextSection, bool NoFinalize = false);
 124
 125   void AddDirectiveHandler(MCAsmParserExtension *Object,
 126                            StringRef Directive,
 127                            DirectiveHandler Handler) {
 128     DirectiveMap[Directive] = std::make_pair(Object, Handler);
 129   }
 130
 131 public:
 132   /// @name MCAsmParser Interface
 133   /// {
 134
 135   virtual SourceMgr &getSourceManager() { return SrcMgr; }
 136   virtual MCAsmLexer &getLexer() { return Lexer; }
 137   virtual MCContext &getContext() { return Ctx; }
 138   virtual MCStreamer &getStreamer() { return Out; }
 139
 140   virtual bool Warning(SMLoc L, const Twine &Msg);
 141   virtual bool Error(SMLoc L, const Twine &Msg);
 142
 143   const AsmToken &Lex();
 144
 145   bool ParseExpression(const MCExpr *&Res);
 146   virtual bool ParseExpression(const MCExpr *&Res, SMLoc &EndLoc);
 147   virtual bool ParseParenExpression(const MCExpr *&Res, SMLoc &EndLoc);
 148   virtual bool ParseAbsoluteExpression(int64_t &Res);
 149
 150   /// }
 151
 152 private:
 153   void CheckForValidSection();
 154
 155   bool ParseStatement();
 156
 157   bool HandleMacroEntry(StringRef Name, SMLoc NameLoc, const Macro *M);
 158   bool expandMacro(SmallString<256> &Buf, StringRef Body,
 159                    const std::vector<StringRef> &Parameters,
 160                    const std::vector<std::vector<AsmToken> > &A,
 161                    const SMLoc &L);
 162   void HandleMacroExit();
 163
 164   void PrintMacroInstantiations();
 165   void PrintMessage(SMLoc Loc, const Twine &Msg, const char *Type,
 166                     bool ShowLine = true) const {
 167     SrcMgr.PrintMessage(Loc, Msg, Type, ShowLine);
 168   }
 169
 170   /// EnterIncludeFile - Enter the specified file. This returns true on failure.
 171   bool EnterIncludeFile(const std::string &Filename);
 172
 173   /// \brief Reset the current lexer position to that given by \arg Loc. The
 174   /// current token is not set; clients should ensure Lex() is called
 175   /// subsequently.
 176   void JumpToLoc(SMLoc Loc);
 177
 178   void EatToEndOfStatement();
 179
 180   /// \brief Parse up to the end of statement and a return the contents from the
 181   /// current token until the end of the statement; the current token on exit
 182   /// will be either the EndOfStatement or EOF.
 183   StringRef ParseStringToEndOfStatement();
 184
 185   bool ParseAssignment(StringRef Name, bool allow_redef);
 186
 187   bool ParsePrimaryExpr(const MCExpr *&Res, SMLoc &EndLoc);
 188   bool ParseBinOpRHS(unsigned Precedence, const MCExpr *&Res, SMLoc &EndLoc);
 189   bool ParseParenExpr(const MCExpr *&Res, SMLoc &EndLoc);
 190   bool ParseBracketExpr(const MCExpr *&Res, SMLoc &EndLoc);
 191
 192   /// ParseIdentifier - Parse an identifier or string (as a quoted identifier)
 193   /// and set \arg Res to the identifier contents.
 194   bool ParseIdentifier(StringRef &Res);
 195
 196   // Directive Parsing.
 197
 198  // ".ascii", ".asciiz", ".string"
 199   bool ParseDirectiveAscii(StringRef IDVal, bool ZeroTerminated);
 200   bool ParseDirectiveValue(unsigned Size); // ".byte", ".long", ...
 201   bool ParseDirectiveRealValue(const fltSemantics &); // ".single", ...
 202   bool ParseDirectiveFill(); // ".fill"
 203   bool ParseDirectiveSpace(); // ".space"
 204   bool ParseDirectiveZero(); // ".zero"
 205   bool ParseDirectiveSet(StringRef IDVal, bool allow_redef); // ".set", ".equ", ".equiv"
 206   bool ParseDirectiveOrg(); // ".org"
 207   // ".align{,32}", ".p2align{,w,l}"
 208   bool ParseDirectiveAlign(bool IsPow2, unsigned ValueSize);
 209
 210   /// ParseDirectiveSymbolAttribute - Parse a directive like ".globl" which
 211   /// accepts a single symbol (which should be a label or an external).
 212   bool ParseDirectiveSymbolAttribute(MCSymbolAttr Attr);
 213
 214   bool ParseDirectiveComm(bool IsLocal); // ".comm" and ".lcomm"
 215
 216   bool ParseDirectiveAbort(); // ".abort"
 217   bool ParseDirectiveInclude(); // ".include"
 218
 219   bool ParseDirectiveIf(SMLoc DirectiveLoc); // ".if"
 220   // ".ifdef" or ".ifndef", depending on expect_defined
 221   bool ParseDirectiveIfdef(SMLoc DirectiveLoc, bool expect_defined);
 222   bool ParseDirectiveElseIf(SMLoc DirectiveLoc); // ".elseif"
 223   bool ParseDirectiveElse(SMLoc DirectiveLoc); // ".else"
 224   bool ParseDirectiveEndIf(SMLoc DirectiveLoc); // .endif
 225
 226   /// ParseEscapedString - Parse the current token as a string which may include
 227   /// escaped characters and return the string contents.
 228   bool ParseEscapedString(std::string &Data);
 229
 230   const MCExpr *ApplyModifierToExpr(const MCExpr *E,
 231                                     MCSymbolRefExpr::VariantKind Variant);
 232 };
 233
 234 /// \brief Generic implementations of directive handling, etc. which is shared
 235 /// (or the default, at least) for all assembler parser.
 236 class GenericAsmParser : public MCAsmParserExtension {
 237   template<bool (GenericAsmParser::*Handler)(StringRef, SMLoc)>
 238   void AddDirectiveHandler(StringRef Directive) {
 239     getParser().AddDirectiveHandler(this, Directive,
 240                                     HandleDirective<GenericAsmParser, Handler>);
 241   }
 242 public:
 243   GenericAsmParser() {}
 244
 245   AsmParser &getParser() {
 246     return (AsmParser&) this->MCAsmParserExtension::getParser();
 247   }
 248
 249   virtual void Initialize(MCAsmParser &Parser) {
 250     // Call the base implementation.
 251     this->MCAsmParserExtension::Initialize(Parser);
 252
 253     // Debugging directives.
 254     AddDirectiveHandler<&GenericAsmParser::ParseDirectiveFile>(".file");
 255     AddDirectiveHandler<&GenericAsmParser::ParseDirectiveLine>(".line");
 256     AddDirectiveHandler<&GenericAsmParser::ParseDirectiveLoc>(".loc");
 257     AddDirectiveHandler<&GenericAsmParser::ParseDirectiveStabs>(".stabs");
 258
 259     // CFI directives.
 260     AddDirectiveHandler<&GenericAsmParser::ParseDirectiveCFISections>(
 261                                                                ".cfi_sections");
 262     AddDirectiveHandler<&GenericAsmParser::ParseDirectiveCFIStartProc>(
 263                                                               ".cfi_startproc");
 264     AddDirectiveHandler<&GenericAsmParser::ParseDirectiveCFIEndProc>(
 265                                                                 ".cfi_endproc");
 266     AddDirectiveHandler<&GenericAsmParser::ParseDirectiveCFIDefCfa>(
 267                                                          ".cfi_def_cfa");
 268     AddDirectiveHandler<&GenericAsmParser::ParseDirectiveCFIDefCfaOffset>(
 269                                                          ".cfi_def_cfa_offset");
 270     AddDirectiveHandler<&GenericAsmParser::ParseDirectiveCFIAdjustCfaOffset>(
 271                                                       ".cfi_adjust_cfa_offset");
 272     AddDirectiveHandler<&GenericAsmParser::ParseDirectiveCFIDefCfaRegister>(
 273                                                        ".cfi_def_cfa_register");
 274     AddDirectiveHandler<&GenericAsmParser::ParseDirectiveCFIOffset>(
 275                                                                  ".cfi_offset");
 276     AddDirectiveHandler<&GenericAsmParser::ParseDirectiveCFIRelOffset>(
 277                                                              ".cfi_rel_offset");
 278     AddDirectiveHandler<
 279      &GenericAsmParser::ParseDirectiveCFIPersonalityOrLsda>(".cfi_personality");
 280     AddDirectiveHandler<
 281             &GenericAsmParser::ParseDirectiveCFIPersonalityOrLsda>(".cfi_lsda");
 282     AddDirectiveHandler<
 283       &GenericAsmParser::ParseDirectiveCFIRememberState>(".cfi_remember_state");
 284     AddDirectiveHandler<
 285       &GenericAsmParser::ParseDirectiveCFIRestoreState>(".cfi_restore_state");
 286     AddDirectiveHandler<
 287       &GenericAsmParser::ParseDirectiveCFISameValue>(".cfi_same_value");
 288
 289     // Macro directives.
 290     AddDirectiveHandler<&GenericAsmParser::ParseDirectiveMacrosOnOff>(
 291       ".macros_on");
 292     AddDirectiveHandler<&GenericAsmParser::ParseDirectiveMacrosOnOff>(
 293       ".macros_off");
 294     AddDirectiveHandler<&GenericAsmParser::ParseDirectiveMacro>(".macro");
 295     AddDirectiveHandler<&GenericAsmParser::ParseDirectiveEndMacro>(".endm");
 296     AddDirectiveHandler<&GenericAsmParser::ParseDirectiveEndMacro>(".endmacro");
 297
 298     AddDirectiveHandler<&GenericAsmParser::ParseDirectiveLEB128>(".sleb128");
 299     AddDirectiveHandler<&GenericAsmParser::ParseDirectiveLEB128>(".uleb128");
 300   }
 301
 302   bool ParseRegisterOrRegisterNumber(int64_t &Register, SMLoc DirectiveLoc);
 303
 304   bool ParseDirectiveFile(StringRef, SMLoc DirectiveLoc);
 305   bool ParseDirectiveLine(StringRef, SMLoc DirectiveLoc);
 306   bool ParseDirectiveLoc(StringRef, SMLoc DirectiveLoc);
 307   bool ParseDirectiveStabs(StringRef, SMLoc DirectiveLoc);
 308   bool ParseDirectiveCFISections(StringRef, SMLoc DirectiveLoc);
 309   bool ParseDirectiveCFIStartProc(StringRef, SMLoc DirectiveLoc);
 310   bool ParseDirectiveCFIEndProc(StringRef, SMLoc DirectiveLoc);
 311   bool ParseDirectiveCFIDefCfa(StringRef, SMLoc DirectiveLoc);
 312   bool ParseDirectiveCFIDefCfaOffset(StringRef, SMLoc DirectiveLoc);
 313   bool ParseDirectiveCFIAdjustCfaOffset(StringRef, SMLoc DirectiveLoc);
 314   bool ParseDirectiveCFIDefCfaRegister(StringRef, SMLoc DirectiveLoc);
 315   bool ParseDirectiveCFIOffset(StringRef, SMLoc DirectiveLoc);
 316   bool ParseDirectiveCFIRelOffset(StringRef, SMLoc DirectiveLoc);
 317   bool ParseDirectiveCFIPersonalityOrLsda(StringRef, SMLoc DirectiveLoc);
 318   bool ParseDirectiveCFIRememberState(StringRef, SMLoc DirectiveLoc);
 319   bool ParseDirectiveCFIRestoreState(StringRef, SMLoc DirectiveLoc);
 320   bool ParseDirectiveCFISameValue(StringRef, SMLoc DirectiveLoc);
 321
 322   bool ParseDirectiveMacrosOnOff(StringRef, SMLoc DirectiveLoc);
 323   bool ParseDirectiveMacro(StringRef, SMLoc DirectiveLoc);
 324   bool ParseDirectiveEndMacro(StringRef, SMLoc DirectiveLoc);
 325
 326   bool ParseDirectiveLEB128(StringRef, SMLoc);
 327 };
 328
 329 }
 330
 331 namespace llvm {
 332
 333 extern MCAsmParserExtension *createDarwinAsmParser();
 334 extern MCAsmParserExtension *createELFAsmParser();
 335 extern MCAsmParserExtension *createCOFFAsmParser();
 336
 337 }
 338
 339 enum { DEFAULT_ADDRSPACE = 0 };
 340
 341 AsmParser::AsmParser(const Target &T, SourceMgr &_SM, MCContext &_Ctx,
 342                      MCStreamer &_Out, const MCAsmInfo &_MAI)
 343   : Lexer(_MAI), Ctx(_Ctx), Out(_Out), MAI(_MAI), SrcMgr(_SM),
 344     GenericParser(new GenericAsmParser), PlatformParser(0),
 345     CurBuffer(0), MacrosEnabled(true) {
 346   Lexer.setBuffer(SrcMgr.getMemoryBuffer(CurBuffer));
 347
 348   // Initialize the generic parser.
 349   GenericParser->Initialize(*this);
 350
 351   // Initialize the platform / file format parser.
 352   //
 353   // FIXME: This is a hack, we need to (majorly) cleanup how these objects are
 354   // created.
 355   if (_MAI.hasMicrosoftFastStdCallMangling()) {
 356     PlatformParser = createCOFFAsmParser();
 357     PlatformParser->Initialize(*this);
 358   } else if (_MAI.hasSubsectionsViaSymbols()) {
 359     PlatformParser = createDarwinAsmParser();
 360     PlatformParser->Initialize(*this);
 361   } else {
 362     PlatformParser = createELFAsmParser();
 363     PlatformParser->Initialize(*this);
 364   }
 365 }
 366
 367 AsmParser::~AsmParser() {
 368   assert(ActiveMacros.empty() && "Unexpected active macro instantiation!");
 369
 370   // Destroy any macros.
 371   for (StringMap<Macro*>::iterator it = MacroMap.begin(),
 372          ie = MacroMap.end(); it != ie; ++it)
 373     delete it->getValue();
 374
 375   delete PlatformParser;
 376   delete GenericParser;
 377 }
 378
 379 void AsmParser::PrintMacroInstantiations() {
 380   // Print the active macro instantiation stack.
 381   for (std::vector<MacroInstantiation*>::const_reverse_iterator
 382          it = ActiveMacros.rbegin(), ie = ActiveMacros.rend(); it != ie; ++it)
 383     PrintMessage((*it)->InstantiationLoc, "while in macro instantiation",
 384                  "note");
 385 }
 386
 387 bool AsmParser::Warning(SMLoc L, const Twine &Msg) {
 388   if (FatalAssemblerWarnings)
 389     return Error(L, Msg);
 390   PrintMessage(L, Msg, "warning");
 391   PrintMacroInstantiations();
 392   return false;
 393 }
 394
 395 bool AsmParser::Error(SMLoc L, const Twine &Msg) {
 396   HadError = true;
 397   PrintMessage(L, Msg, "error");
 398   PrintMacroInstantiations();
 399   return true;
 400 }
 401
 402 bool AsmParser::EnterIncludeFile(const std::string &Filename) {
 403   std::string IncludedFile;
 404   int NewBuf = SrcMgr.AddIncludeFile(Filename, Lexer.getLoc(), IncludedFile);
 405   if (NewBuf == -1)
 406     return true;
 407
 408   CurBuffer = NewBuf;
 409
 410   Lexer.setBuffer(SrcMgr.getMemoryBuffer(CurBuffer));
 411
 412   return false;
 413 }
 414
 415 void AsmParser::JumpToLoc(SMLoc Loc) {
 416   CurBuffer = SrcMgr.FindBufferContainingLoc(Loc);
 417   Lexer.setBuffer(SrcMgr.getMemoryBuffer(CurBuffer), Loc.getPointer());
 418 }
 419
 420 const AsmToken &AsmParser::Lex() {
 421   const AsmToken *tok = &Lexer.Lex();
 422
 423   if (tok->is(AsmToken::Eof)) {
 424     // If this is the end of an included file, pop the parent file off the
 425     // include stack.
 426     SMLoc ParentIncludeLoc = SrcMgr.getParentIncludeLoc(CurBuffer);
 427     if (ParentIncludeLoc != SMLoc()) {
 428       JumpToLoc(ParentIncludeLoc);
 429       tok = &Lexer.Lex();
 430     }
 431   }
 432
 433   if (tok->is(AsmToken::Error))
 434     Error(Lexer.getErrLoc(), Lexer.getErr());
 435
 436   return *tok;
 437 }
 438
 439 bool AsmParser::Run(bool NoInitialTextSection, bool NoFinalize) {
 440   // Create the initial section, if requested.
 441   if (!NoInitialTextSection)
 442     Out.InitSections();
 443
 444   // Prime the lexer.
 445   Lex();
 446
 447   HadError = false;
 448   AsmCond StartingCondState = TheCondState;
 449
 450   // While we have input, parse each statement.
 451   while (Lexer.isNot(AsmToken::Eof)) {
 452     if (!ParseStatement()) continue;
 453
 454     // We had an error, validate that one was emitted and recover by skipping to
 455     // the next line.
 456     assert(HadError && "Parse statement returned an error, but none emitted!");
 457     EatToEndOfStatement();
 458   }
 459
 460   if (TheCondState.TheCond != StartingCondState.TheCond ||
 461       TheCondState.Ignore != StartingCondState.Ignore)
 462     return TokError("unmatched .ifs or .elses");
 463
 464   // Check to see there are no empty DwarfFile slots.
 465   const std::vector<MCDwarfFile *> &MCDwarfFiles =
 466     getContext().getMCDwarfFiles();
 467   for (unsigned i = 1; i < MCDwarfFiles.size(); i++) {
 468     if (!MCDwarfFiles[i])
 469       TokError("unassigned file number: " + Twine(i) + " for .file directives");
 470   }
 471
 472   // Check to see that all assembler local symbols were actually defined.
 473   // Targets that don't do subsections via symbols may not want this, though,
 474   // so conservatively exclude them. Only do this if we're finalizing, though,
 475   // as otherwise we won't necessarilly have seen everything yet.
 476   if (!NoFinalize && MAI.hasSubsectionsViaSymbols()) {
 477     const MCContext::SymbolTable &Symbols = getContext().getSymbols();
 478     for (MCContext::SymbolTable::const_iterator i = Symbols.begin(),
 479          e = Symbols.end();
 480          i != e; ++i) {
 481       MCSymbol *Sym = i->getValue();
 482       // Variable symbols may not be marked as defined, so check those
 483       // explicitly. If we know it's a variable, we have a definition for
 484       // the purposes of this check.
 485       if (Sym->isTemporary() && !Sym->isVariable() && !Sym->isDefined())
 486         // FIXME: We would really like to refer back to where the symbol was
 487         // first referenced for a source location. We need to add something
 488         // to track that. Currently, we just point to the end of the file.
 489         PrintMessage(getLexer().getLoc(), "assembler local symbol '" +
 490                      Sym->getName() + "' not defined", "error", false);
 491     }
 492   }
 493
 494
 495   // Finalize the output stream if there are no errors and if the client wants
 496   // us to.
 497   if (!HadError && !NoFinalize)
 498     Out.Finish();
 499
 500   return HadError;
 501 }
 502
 503 void AsmParser::CheckForValidSection() {
 504   if (!getStreamer().getCurrentSection()) {
 505     TokError("expected section directive before assembly directive");
 506     Out.SwitchSection(Ctx.getMachOSection(
 507                         "__TEXT", "__text",
 508                         MCSectionMachO::S_ATTR_PURE_INSTRUCTIONS,
 509                         0, SectionKind::getText()));
 510   }
 511 }
 512
 513 /// EatToEndOfStatement - Throw away the rest of the line for testing purposes.
 514 void AsmParser::EatToEndOfStatement() {
 515   while (Lexer.isNot(AsmToken::EndOfStatement) &&
 516          Lexer.isNot(AsmToken::Eof))
 517     Lex();
 518
 519   // Eat EOL.
 520   if (Lexer.is(AsmToken::EndOfStatement))
 521     Lex();
 522 }
 523
 524 StringRef AsmParser::ParseStringToEndOfStatement() {
 525   const char *Start = getTok().getLoc().getPointer();
 526
 527   while (Lexer.isNot(AsmToken::EndOfStatement) &&
 528          Lexer.isNot(AsmToken::Eof))
 529     Lex();
 530
 531   const char *End = getTok().getLoc().getPointer();
 532   return StringRef(Start, End - Start);
 533 }
 534
 535 /// ParseParenExpr - Parse a paren expression and return it.
 536 /// NOTE: This assumes the leading '(' has already been consumed.
 537 ///
 538 /// parenexpr ::= expr)
 539 ///
 540 bool AsmParser::ParseParenExpr(const MCExpr *&Res, SMLoc &EndLoc) {
 541   if (ParseExpression(Res)) return true;
 542   if (Lexer.isNot(AsmToken::RParen))
 543     return TokError("expected ')' in parentheses expression");
 544   EndLoc = Lexer.getLoc();
 545   Lex();
 546   return false;
 547 }
 548
 549 /// ParseBracketExpr - Parse a bracket expression and return it.
 550 /// NOTE: This assumes the leading '[' has already been consumed.
 551 ///
 552 /// bracketexpr ::= expr]
 553 ///
 554 bool AsmParser::ParseBracketExpr(const MCExpr *&Res, SMLoc &EndLoc) {
 555   if (ParseExpression(Res)) return true;
 556   if (Lexer.isNot(AsmToken::RBrac))
 557     return TokError("expected ']' in brackets expression");
 558   EndLoc = Lexer.getLoc();
 559   Lex();
 560   return false;
 561 }
 562
 563 /// ParsePrimaryExpr - Parse a primary expression and return it.
 564 ///  primaryexpr ::= (parenexpr
 565 ///  primaryexpr ::= symbol
 566 ///  primaryexpr ::= number
 567 ///  primaryexpr ::= '.'
 568 ///  primaryexpr ::= ~,+,- primaryexpr
 569 bool AsmParser::ParsePrimaryExpr(const MCExpr *&Res, SMLoc &EndLoc) {
 570   switch (Lexer.getKind()) {
 571   default:
 572     return TokError("unknown token in expression");
 573   // If we have an error assume that we've already handled it.
 574   case AsmToken::Error:
 575     return true;
 576   case AsmToken::Exclaim:
 577     Lex(); // Eat the operator.
 578     if (ParsePrimaryExpr(Res, EndLoc))
 579       return true;
 580     Res = MCUnaryExpr::CreateLNot(Res, getContext());
 581     return false;
 582   case AsmToken::Dollar:
 583   case AsmToken::String:
 584   case AsmToken::Identifier: {
 585     EndLoc = Lexer.getLoc();
 586
 587     StringRef Identifier;
 588     if (ParseIdentifier(Identifier))
 589       return true;
 590
 591     // This is a symbol reference.
 592     std::pair<StringRef, StringRef> Split = Identifier.split('@');
 593     MCSymbol *Sym = getContext().GetOrCreateSymbol(Split.first);
 594
 595     // Lookup the symbol variant if used.
 596     MCSymbolRefExpr::VariantKind Variant = MCSymbolRefExpr::VK_None;
 597     if (Split.first.size() != Identifier.size()) {
 598       Variant = MCSymbolRefExpr::getVariantKindForName(Split.second);
 599       if (Variant == MCSymbolRefExpr::VK_Invalid) {
 600         Variant = MCSymbolRefExpr::VK_None;
 601         return TokError("invalid variant '" + Split.second + "'");
 602       }
 603     }
 604
 605     // If this is an absolute variable reference, substitute it now to preserve
 606     // semantics in the face of reassignment.
 607     if (Sym->isVariable() && isa<MCConstantExpr>(Sym->getVariableValue())) {
 608       if (Variant)
 609         return Error(EndLoc, "unexpected modifier on variable reference");
 610
 611       Res = Sym->getVariableValue();
 612       return false;
 613     }
 614
 615     // Otherwise create a symbol ref.
 616     Res = MCSymbolRefExpr::Create(Sym, Variant, getContext());
 617     return false;
 618   }
 619   case AsmToken::Integer: {
 620     SMLoc Loc = getTok().getLoc();
 621     int64_t IntVal = getTok().getIntVal();
 622     Res = MCConstantExpr::Create(IntVal, getContext());
 623     EndLoc = Lexer.getLoc();
 624     Lex(); // Eat token.
 625     // Look for 'b' or 'f' following an Integer as a directional label
 626     if (Lexer.getKind() == AsmToken::Identifier) {
 627       StringRef IDVal = getTok().getString();
 628       if (IDVal == "f" || IDVal == "b"){
 629         MCSymbol *Sym = Ctx.GetDirectionalLocalSymbol(IntVal,
 630                                                       IDVal == "f" ? 1 : 0);
 631         Res = MCSymbolRefExpr::Create(Sym, MCSymbolRefExpr::VK_None,
 632                                       getContext());
 633         if(IDVal == "b" && Sym->isUndefined())
 634           return Error(Loc, "invalid reference to undefined symbol");
 635         EndLoc = Lexer.getLoc();
 636         Lex(); // Eat identifier.
 637       }
 638     }
 639     return false;
 640   }
 641   case AsmToken::Real: {
 642     APFloat RealVal(APFloat::IEEEdouble, getTok().getString());
 643     uint64_t IntVal = RealVal.bitcastToAPInt().getZExtValue();
 644     Res = MCConstantExpr::Create(IntVal, getContext());
 645     Lex(); // Eat token.
 646     return false;
 647   }
 648   case AsmToken::Dot: {
 649     // This is a '.' reference, which references the current PC.  Emit a
 650     // temporary label to the streamer and refer to it.
 651     MCSymbol *Sym = Ctx.CreateTempSymbol();
 652     Out.EmitLabel(Sym);
 653     Res = MCSymbolRefExpr::Create(Sym, MCSymbolRefExpr::VK_None, getContext());
 654     EndLoc = Lexer.getLoc();
 655     Lex(); // Eat identifier.
 656     return false;
 657   }
 658   case AsmToken::LParen:
 659     Lex(); // Eat the '('.
 660     return ParseParenExpr(Res, EndLoc);
 661   case AsmToken::LBrac:
 662     if (!PlatformParser->HasBracketExpressions())
 663       return TokError("brackets expression not supported on this target");
 664     Lex(); // Eat the '['.
 665     return ParseBracketExpr(Res, EndLoc);
 666   case AsmToken::Minus:
 667     Lex(); // Eat the operator.
 668     if (ParsePrimaryExpr(Res, EndLoc))
 669       return true;
 670     Res = MCUnaryExpr::CreateMinus(Res, getContext());
 671     return false;
 672   case AsmToken::Plus:
 673     Lex(); // Eat the operator.
 674     if (ParsePrimaryExpr(Res, EndLoc))
 675       return true;
 676     Res = MCUnaryExpr::CreatePlus(Res, getContext());
 677     return false;
 678   case AsmToken::Tilde:
 679     Lex(); // Eat the operator.
 680     if (ParsePrimaryExpr(Res, EndLoc))
 681       return true;
 682     Res = MCUnaryExpr::CreateNot(Res, getContext());
 683     return false;
 684   }
 685 }
 686
 687 bool AsmParser::ParseExpression(const MCExpr *&Res) {
 688   SMLoc EndLoc;
 689   return ParseExpression(Res, EndLoc);
 690 }
 691
 692 const MCExpr *
 693 AsmParser::ApplyModifierToExpr(const MCExpr *E,
 694                                MCSymbolRefExpr::VariantKind Variant) {
 695   // Recurse over the given expression, rebuilding it to apply the given variant
 696   // if there is exactly one symbol.
 697   switch (E->getKind()) {
 698   case MCExpr::Target:
 699   case MCExpr::Constant:
 700     return 0;
 701
 702   case MCExpr::SymbolRef: {
 703     const MCSymbolRefExpr *SRE = cast<MCSymbolRefExpr>(E);
 704
 705     if (SRE->getKind() != MCSymbolRefExpr::VK_None) {
 706       TokError("invalid variant on expression '" +
 707                getTok().getIdentifier() + "' (already modified)");
 708       return E;
 709     }
 710
 711     return MCSymbolRefExpr::Create(&SRE->getSymbol(), Variant, getContext());
 712   }
 713
 714   case MCExpr::Unary: {
 715     const MCUnaryExpr *UE = cast<MCUnaryExpr>(E);
 716     const MCExpr *Sub = ApplyModifierToExpr(UE->getSubExpr(), Variant);
 717     if (!Sub)
 718       return 0;
 719     return MCUnaryExpr::Create(UE->getOpcode(), Sub, getContext());
 720   }
 721
 722   case MCExpr::Binary: {
 723     const MCBinaryExpr *BE = cast<MCBinaryExpr>(E);
 724     const MCExpr *LHS = ApplyModifierToExpr(BE->getLHS(), Variant);
 725     const MCExpr *RHS = ApplyModifierToExpr(BE->getRHS(), Variant);
 726
 727     if (!LHS && !RHS)
 728       return 0;
 729
 730     if (!LHS) LHS = BE->getLHS();
 731     if (!RHS) RHS = BE->getRHS();
 732
 733     return MCBinaryExpr::Create(BE->getOpcode(), LHS, RHS, getContext());
 734   }
 735   }
 736
 737   assert(0 && "Invalid expression kind!");
 738   return 0;
 739 }
 740
 741 /// ParseExpression - Parse an expression and return it.
 742 ///
 743 ///  expr ::= expr +,- expr          -> lowest.
 744 ///  expr ::= expr |,^,&,! expr      -> middle.
 745 ///  expr ::= expr *,/,%,<<,>> expr  -> highest.
 746 ///  expr ::= primaryexpr
 747 ///
 748 bool AsmParser::ParseExpression(const MCExpr *&Res, SMLoc &EndLoc) {
 749   // Parse the expression.
 750   Res = 0;
 751   if (ParsePrimaryExpr(Res, EndLoc) || ParseBinOpRHS(1, Res, EndLoc))
 752     return true;
 753
 754   // As a special case, we support 'a op b @ modifier' by rewriting the
 755   // expression to include the modifier. This is inefficient, but in general we
 756   // expect users to use 'a@modifier op b'.
 757   if (Lexer.getKind() == AsmToken::At) {
 758     Lex();
 759
 760     if (Lexer.isNot(AsmToken::Identifier))
 761       return TokError("unexpected symbol modifier following '@'");
 762
 763     MCSymbolRefExpr::VariantKind Variant =
 764       MCSymbolRefExpr::getVariantKindForName(getTok().getIdentifier());
 765     if (Variant == MCSymbolRefExpr::VK_Invalid)
 766       return TokError("invalid variant '" + getTok().getIdentifier() + "'");
 767
 768     const MCExpr *ModifiedRes = ApplyModifierToExpr(Res, Variant);
 769     if (!ModifiedRes) {
 770       return TokError("invalid modifier '" + getTok().getIdentifier() +
 771                       "' (no symbols present)");
 772       return true;
 773     }
 774
 775     Res = ModifiedRes;
 776     Lex();
 777   }
 778
 779   // Try to constant fold it up front, if possible.
 780   int64_t Value;
 781   if (Res->EvaluateAsAbsolute(Value))
 782     Res = MCConstantExpr::Create(Value, getContext());
 783
 784   return false;
 785 }
 786
 787 bool AsmParser::ParseParenExpression(const MCExpr *&Res, SMLoc &EndLoc) {
 788   Res = 0;
 789   return ParseParenExpr(Res, EndLoc) ||
 790          ParseBinOpRHS(1, Res, EndLoc);
 791 }
 792
 793 bool AsmParser::ParseAbsoluteExpression(int64_t &Res) {
 794   const MCExpr *Expr;
 795
 796   SMLoc StartLoc = Lexer.getLoc();
 797   if (ParseExpression(Expr))
 798     return true;
 799
 800   if (!Expr->EvaluateAsAbsolute(Res))
 801     return Error(StartLoc, "expected absolute expression");
 802
 803   return false;
 804 }
 805
 806 static unsigned getBinOpPrecedence(AsmToken::TokenKind K,
 807                                    MCBinaryExpr::Opcode &Kind) {
 808   switch (K) {
 809   default:
 810     return 0;    // not a binop.
 811
 812     // Lowest Precedence: &&, ||, @
 813   case AsmToken::AmpAmp:
 814     Kind = MCBinaryExpr::LAnd;
 815     return 1;
 816   case AsmToken::PipePipe:
 817     Kind = MCBinaryExpr::LOr;
 818     return 1;
 819
 820
 821     // Low Precedence: |, &, ^
 822     //
 823     // FIXME: gas seems to support '!' as an infix operator?
 824   case AsmToken::Pipe:
 825     Kind = MCBinaryExpr::Or;
 826     return 2;
 827   case AsmToken::Caret:
 828     Kind = MCBinaryExpr::Xor;
 829     return 2;
 830   case AsmToken::Amp:
 831     Kind = MCBinaryExpr::And;
 832     return 2;
 833
 834     // Low Intermediate Precedence: ==, !=, <>, <, <=, >, >=
 835   case AsmToken::EqualEqual:
 836     Kind = MCBinaryExpr::EQ;
 837     return 3;
 838   case AsmToken::ExclaimEqual:
 839   case AsmToken::LessGreater:
 840     Kind = MCBinaryExpr::NE;
 841     return 3;
 842   case AsmToken::Less:
 843     Kind = MCBinaryExpr::LT;
 844     return 3;
 845   case AsmToken::LessEqual:
 846     Kind = MCBinaryExpr::LTE;
 847     return 3;
 848   case AsmToken::Greater:
 849     Kind = MCBinaryExpr::GT;
 850     return 3;
 851   case AsmToken::GreaterEqual:
 852     Kind = MCBinaryExpr::GTE;
 853     return 3;
 854
 855     // High Intermediate Precedence: +, -
 856   case AsmToken::Plus:
 857     Kind = MCBinaryExpr::Add;
 858     return 4;
 859   case AsmToken::Minus:
 860     Kind = MCBinaryExpr::Sub;
 861     return 4;
 862
 863     // Highest Precedence: *, /, %, <<, >>
 864   case AsmToken::Star:
 865     Kind = MCBinaryExpr::Mul;
 866     return 5;
 867   case AsmToken::Slash:
 868     Kind = MCBinaryExpr::Div;
 869     return 5;
 870   case AsmToken::Percent:
 871     Kind = MCBinaryExpr::Mod;
 872     return 5;
 873   case AsmToken::LessLess:
 874     Kind = MCBinaryExpr::Shl;
 875     return 5;
 876   case AsmToken::GreaterGreater:
 877     Kind = MCBinaryExpr::Shr;
 878     return 5;
 879   }
 880 }
 881
 882
 883 /// ParseBinOpRHS - Parse all binary operators with precedence >= 'Precedence'.
 884 /// Res contains the LHS of the expression on input.
 885 bool AsmParser::ParseBinOpRHS(unsigned Precedence, const MCExpr *&Res,
 886                               SMLoc &EndLoc) {
 887   while (1) {
 888     MCBinaryExpr::Opcode Kind = MCBinaryExpr::Add;
 889     unsigned TokPrec = getBinOpPrecedence(Lexer.getKind(), Kind);
 890
 891     // If the next token is lower precedence than we are allowed to eat, return
 892     // successfully with what we ate already.
 893     if (TokPrec < Precedence)
 894       return false;
 895
 896     Lex();
 897
 898     // Eat the next primary expression.
 899     const MCExpr *RHS;
 900     if (ParsePrimaryExpr(RHS, EndLoc)) return true;
 901
 902     // If BinOp binds less tightly with RHS than the operator after RHS, let
 903     // the pending operator take RHS as its LHS.
 904     MCBinaryExpr::Opcode Dummy;
 905     unsigned NextTokPrec = getBinOpPrecedence(Lexer.getKind(), Dummy);
 906     if (TokPrec < NextTokPrec) {
 907       if (ParseBinOpRHS(Precedence+1, RHS, EndLoc)) return true;
 908     }
 909
 910     // Merge LHS and RHS according to operator.
 911     Res = MCBinaryExpr::Create(Kind, Res, RHS, getContext());
 912   }
 913 }
 914
 915
 916
 917
 918 /// ParseStatement:
 919 ///   ::= EndOfStatement
 920 ///   ::= Label* Directive ...Operands... EndOfStatement
 921 ///   ::= Label* Identifier OperandList* EndOfStatement
 922 bool AsmParser::ParseStatement() {
 923   if (Lexer.is(AsmToken::EndOfStatement)) {
 924     Out.AddBlankLine();
 925     Lex();
 926     return false;
 927   }
 928
 929   // Statements always start with an identifier or are a full line comment.
 930   AsmToken ID = getTok();
 931   SMLoc IDLoc = ID.getLoc();
 932   StringRef IDVal;
 933   int64_t LocalLabelVal = -1;
 934   // A full line comment is a '#' as the first token.
 935   if (Lexer.is(AsmToken::Hash)) {
 936     EatToEndOfStatement();
 937     return false;
 938   }
 939
 940   // Allow an integer followed by a ':' as a directional local label.
 941   if (Lexer.is(AsmToken::Integer)) {
 942     LocalLabelVal = getTok().getIntVal();
 943     if (LocalLabelVal < 0) {
 944       if (!TheCondState.Ignore)
 945         return TokError("unexpected token at start of statement");
 946       IDVal = "";
 947     }
 948     else {
 949       IDVal = getTok().getString();
 950       Lex(); // Consume the integer token to be used as an identifier token.
 951       if (Lexer.getKind() != AsmToken::Colon) {
 952         if (!TheCondState.Ignore)
 953           return TokError("unexpected token at start of statement");
 954       }
 955     }
 956
 957   } else if (Lexer.is(AsmToken::Dot)) {
 958     // Treat '.' as a valid identifier in this context.
 959     Lex();
 960     IDVal = ".";
 961
 962   } else if (ParseIdentifier(IDVal)) {
 963     if (!TheCondState.Ignore)
 964       return TokError("unexpected token at start of statement");
 965     IDVal = "";
 966   }
 967
 968
 969   // Handle conditional assembly here before checking for skipping.  We
 970   // have to do this so that .endif isn't skipped in a ".if 0" block for
 971   // example.
 972   if (IDVal == ".if")
 973     return ParseDirectiveIf(IDLoc);
 974   if (IDVal == ".ifdef")
 975     return ParseDirectiveIfdef(IDLoc, true);
 976   if (IDVal == ".ifndef" || IDVal == ".ifnotdef")
 977     return ParseDirectiveIfdef(IDLoc, false);
 978   if (IDVal == ".elseif")
 979     return ParseDirectiveElseIf(IDLoc);
 980   if (IDVal == ".else")
 981     return ParseDirectiveElse(IDLoc);
 982   if (IDVal == ".endif")
 983     return ParseDirectiveEndIf(IDLoc);
 984
 985   // If we are in a ".if 0" block, ignore this statement.
 986   if (TheCondState.Ignore) {
 987     EatToEndOfStatement();
 988     return false;
 989   }
 990
 991   // FIXME: Recurse on local labels?
 992
 993   // See what kind of statement we have.
 994   switch (Lexer.getKind()) {
 995   case AsmToken::Colon: {
 996     CheckForValidSection();
 997
 998     // identifier ':'   -> Label.
 999     Lex();
1000
1001     // Diagnose attempt to use '.' as a label.
1002     if (IDVal == ".")
1003       return Error(IDLoc, "invalid use of pseudo-symbol '.' as a label");
1004
1005     // Diagnose attempt to use a variable as a label.
1006     //
1007     // FIXME: Diagnostics. Note the location of the definition as a label.
1008     // FIXME: This doesn't diagnose assignment to a symbol which has been
1009     // implicitly marked as external.
1010     MCSymbol *Sym;
1011     if (LocalLabelVal == -1)
1012       Sym = getContext().GetOrCreateSymbol(IDVal);
1013     else
1014       Sym = Ctx.CreateDirectionalLocalSymbol(LocalLabelVal);
1015     if (!Sym->isUndefined() || Sym->isVariable())
1016       return Error(IDLoc, "invalid symbol redefinition");
1017
1018     // Emit the label.
1019     Out.EmitLabel(Sym);
1020
1021     // Consume any end of statement token, if present, to avoid spurious
1022     // AddBlankLine calls().
1023     if (Lexer.is(AsmToken::EndOfStatement)) {
1024       Lex();
1025       if (Lexer.is(AsmToken::Eof))
1026         return false;
1027     }
1028
1029     return ParseStatement();
1030   }
1031
1032   case AsmToken::Equal:
1033     // identifier '=' ... -> assignment statement
1034     Lex();
1035
1036     return ParseAssignment(IDVal, true);
1037
1038   default: // Normal instruction or directive.
1039     break;
1040   }
1041
1042   // If macros are enabled, check to see if this is a macro instantiation.
1043   if (MacrosEnabled)
1044     if (const Macro *M = MacroMap.lookup(IDVal))
1045       return HandleMacroEntry(IDVal, IDLoc, M);
1046
1047   // Otherwise, we have a normal instruction or directive.
1048   if (IDVal[0] == '.' && IDVal != ".") {
1049     // Assembler features
1050     if (IDVal == ".set" || IDVal == ".equ")
1051       return ParseDirectiveSet(IDVal, true);
1052     if (IDVal == ".equiv")
1053       return ParseDirectiveSet(IDVal, false);
1054
1055     // Data directives
1056
1057     if (IDVal == ".ascii")
1058       return ParseDirectiveAscii(IDVal, false);
1059     if (IDVal == ".asciz" || IDVal == ".string")
1060       return ParseDirectiveAscii(IDVal, true);
1061
1062     if (IDVal == ".byte")
1063       return ParseDirectiveValue(1);
1064     if (IDVal == ".short")
1065       return ParseDirectiveValue(2);
1066     if (IDVal == ".value")
1067       return ParseDirectiveValue(2);
1068     if (IDVal == ".2byte")
1069       return ParseDirectiveValue(2);
1070     if (IDVal == ".long")
1071       return ParseDirectiveValue(4);
1072     if (IDVal == ".int")
1073       return ParseDirectiveValue(4);
1074     if (IDVal == ".4byte")
1075       return ParseDirectiveValue(4);
1076     if (IDVal == ".quad")
1077       return ParseDirectiveValue(8);
1078     if (IDVal == ".8byte")
1079       return ParseDirectiveValue(8);
1080     if (IDVal == ".single" || IDVal == ".float")
1081       return ParseDirectiveRealValue(APFloat::IEEEsingle);
1082     if (IDVal == ".double")
1083       return ParseDirectiveRealValue(APFloat::IEEEdouble);
1084
1085     if (IDVal == ".align") {
1086       bool IsPow2 = !getContext().getAsmInfo().getAlignmentIsInBytes();
1087       return ParseDirectiveAlign(IsPow2, /*ExprSize=*/1);
1088     }
1089     if (IDVal == ".align32") {
1090       bool IsPow2 = !getContext().getAsmInfo().getAlignmentIsInBytes();
1091       return ParseDirectiveAlign(IsPow2, /*ExprSize=*/4);
1092     }
1093     if (IDVal == ".balign")
1094       return ParseDirectiveAlign(/*IsPow2=*/false, /*ExprSize=*/1);
1095     if (IDVal == ".balignw")
1096       return ParseDirectiveAlign(/*IsPow2=*/false, /*ExprSize=*/2);
1097     if (IDVal == ".balignl")
1098       return ParseDirectiveAlign(/*IsPow2=*/false, /*ExprSize=*/4);
1099     if (IDVal == ".p2align")
1100       return ParseDirectiveAlign(/*IsPow2=*/true, /*ExprSize=*/1);
1101     if (IDVal == ".p2alignw")
1102       return ParseDirectiveAlign(/*IsPow2=*/true, /*ExprSize=*/2);
1103     if (IDVal == ".p2alignl")
1104       return ParseDirectiveAlign(/*IsPow2=*/true, /*ExprSize=*/4);
1105
1106     if (IDVal == ".org")
1107       return ParseDirectiveOrg();
1108
1109     if (IDVal == ".fill")
1110       return ParseDirectiveFill();
1111     if (IDVal == ".space" || IDVal == ".skip")
1112       return ParseDirectiveSpace();
1113     if (IDVal == ".zero")
1114       return ParseDirectiveZero();
1115
1116     // Symbol attribute directives
1117
1118     if (IDVal == ".globl" || IDVal == ".global")
1119       return ParseDirectiveSymbolAttribute(MCSA_Global);
1120     // ELF only? Should it be here?
1121     if (IDVal == ".local")
1122       return ParseDirectiveSymbolAttribute(MCSA_Local);
1123     if (IDVal == ".hidden")
1124       return ParseDirectiveSymbolAttribute(MCSA_Hidden);
1125     if (IDVal == ".indirect_symbol")
1126       return ParseDirectiveSymbolAttribute(MCSA_IndirectSymbol);
1127     if (IDVal == ".internal")
1128       return ParseDirectiveSymbolAttribute(MCSA_Internal);
1129     if (IDVal == ".lazy_reference")
1130       return ParseDirectiveSymbolAttribute(MCSA_LazyReference);
1131     if (IDVal == ".no_dead_strip")
1132       return ParseDirectiveSymbolAttribute(MCSA_NoDeadStrip);
1133     if (IDVal == ".symbol_resolver")
1134       return ParseDirectiveSymbolAttribute(MCSA_SymbolResolver);
1135     if (IDVal == ".private_extern")
1136       return ParseDirectiveSymbolAttribute(MCSA_PrivateExtern);
1137     if (IDVal == ".protected")
1138       return ParseDirectiveSymbolAttribute(MCSA_Protected);
1139     if (IDVal == ".reference")
1140       return ParseDirectiveSymbolAttribute(MCSA_Reference);
1141     if (IDVal == ".weak")
1142       return ParseDirectiveSymbolAttribute(MCSA_Weak);
1143     if (IDVal == ".weak_definition")
1144       return ParseDirectiveSymbolAttribute(MCSA_WeakDefinition);
1145     if (IDVal == ".weak_reference")
1146       return ParseDirectiveSymbolAttribute(MCSA_WeakReference);
1147     if (IDVal == ".weak_def_can_be_hidden")
1148       return ParseDirectiveSymbolAttribute(MCSA_WeakDefAutoPrivate);
1149
1150     if (IDVal == ".comm" || IDVal == ".common")
1151       return ParseDirectiveComm(/*IsLocal=*/false);
1152     if (IDVal == ".lcomm")
1153       return ParseDirectiveComm(/*IsLocal=*/true);
1154
1155     if (IDVal == ".abort")
1156       return ParseDirectiveAbort();
1157     if (IDVal == ".include")
1158       return ParseDirectiveInclude();
1159
1160     if (IDVal == ".code16" || IDVal == ".code32" || IDVal == ".code64")
1161       return TokError(Twine(IDVal) + " not supported yet");
1162
1163     // Look up the handler in the handler table.
1164     std::pair<MCAsmParserExtension*, DirectiveHandler> Handler =
1165       DirectiveMap.lookup(IDVal);
1166     if (Handler.first)
1167       return (*Handler.second)(Handler.first, IDVal, IDLoc);
1168
1169     // Target hook for parsing target specific directives.
1170     if (!getTargetParser().ParseDirective(ID))
1171       return false;
1172
1173     bool retval = Warning(IDLoc, "ignoring directive for now");
1174     EatToEndOfStatement();
1175     return retval;
1176   }
1177
1178   CheckForValidSection();
1179
1180   // Canonicalize the opcode to lower case.
1181   SmallString<128> Opcode;
1182   for (unsigned i = 0, e = IDVal.size(); i != e; ++i)
1183     Opcode.push_back(tolower(IDVal[i]));
1184
1185   SmallVector<MCParsedAsmOperand*, 8> ParsedOperands;
1186   bool HadError = getTargetParser().ParseInstruction(Opcode.str(), IDLoc,
1187                                                      ParsedOperands);
1188
1189   // Dump the parsed representation, if requested.
1190   if (getShowParsedOperands()) {
1191     SmallString<256> Str;
1192     raw_svector_ostream OS(Str);
1193     OS << "parsed instruction: [";
1194     for (unsigned i = 0; i != ParsedOperands.size(); ++i) {
1195       if (i != 0)
1196         OS << ", ";
1197       ParsedOperands[i]->dump(OS);
1198     }
1199     OS << "]";
1200
1201     PrintMessage(IDLoc, OS.str(), "note");
1202   }
1203
1204   // If parsing succeeded, match the instruction.
1205   if (!HadError)
1206     HadError = getTargetParser().MatchAndEmitInstruction(IDLoc, ParsedOperands,
1207                                                          Out);
1208
1209   // Free any parsed operands.
1210   for (unsigned i = 0, e = ParsedOperands.size(); i != e; ++i)
1211     delete ParsedOperands[i];
1212
1213   // Don't skip the rest of the line, the instruction parser is responsible for
1214   // that.
1215   return false;
1216 }
1217
1218 bool AsmParser::expandMacro(SmallString<256> &Buf, StringRef Body,
1219                             const std::vector<StringRef> &Parameters,
1220                             const std::vector<std::vector<AsmToken> > &A,
1221                             const SMLoc &L) {
1222   raw_svector_ostream OS(Buf);
1223   unsigned NParameters = Parameters.size();
1224   if (NParameters != 0 && NParameters != A.size())
1225     return Error(L, "Wrong number of arguments");
1226
1227   while (!Body.empty()) {
1228     // Scan for the next substitution.
1229     std::size_t End = Body.size(), Pos = 0;
1230     for (; Pos != End; ++Pos) {
1231       // Check for a substitution or escape.
1232       if (!NParameters) {
1233         // This macro has no parameters, look for $0, $1, etc.
1234         if (Body[Pos] != '$' || Pos + 1 == End)
1235           continue;
1236
1237         char Next = Body[Pos + 1];
1238         if (Next == '$' || Next == 'n' || isdigit(Next))
1239           break;
1240       } else {
1241         // This macro has parameters, look for \foo, \bar, etc.
1242         if (Body[Pos] == '\\' && Pos + 1 != End)
1243           break;
1244       }
1245     }
1246
1247     // Add the prefix.
1248     OS << Body.slice(0, Pos);
1249
1250     // Check if we reached the end.
1251     if (Pos == End)
1252       break;
1253
1254     if (!NParameters) {
1255       switch (Body[Pos+1]) {
1256         // $$ => $
1257       case '$':
1258         OS << '$';
1259         break;
1260
1261         // $n => number of arguments
1262       case 'n':
1263         OS << A.size();
1264         break;
1265
1266         // $[0-9] => argument
1267       default: {
1268         // Missing arguments are ignored.
1269         unsigned Index = Body[Pos+1] - '0';
1270         if (Index >= A.size())
1271           break;
1272
1273         // Otherwise substitute with the token values, with spaces eliminated.
1274         for (std::vector<AsmToken>::const_iterator it = A[Index].begin(),
1275                ie = A[Index].end(); it != ie; ++it)
1276           OS << it->getString();
1277         break;
1278       }
1279       }
1280       Pos += 2;
1281     } else {
1282       unsigned I = Pos + 1;
1283       while (isalnum(Body[I]) && I + 1 != End)
1284         ++I;
1285
1286       const char *Begin = Body.data() + Pos +1;
1287       StringRef Argument(Begin, I - (Pos +1));
1288       unsigned Index = 0;
1289       for (; Index < NParameters; ++Index)
1290         if (Parameters[Index] == Argument)
1291           break;
1292
1293       // FIXME: We should error at the macro definition.
1294       if (Index == NParameters)
1295         return Error(L, "Parameter not found");
1296
1297       for (std::vector<AsmToken>::const_iterator it = A[Index].begin(),
1298              ie = A[Index].end(); it != ie; ++it)
1299         OS << it->getString();
1300
1301       Pos += 1 + Argument.size();
1302     }
1303     // Update the scan point.
1304     Body = Body.substr(Pos);
1305   }
1306
1307   // We include the .endmacro in the buffer as our queue to exit the macro
1308   // instantiation.
1309   OS << ".endmacro\n";
1310   return false;
1311 }
1312
1313 MacroInstantiation::MacroInstantiation(const Macro *M, SMLoc IL, SMLoc EL,
1314                                        MemoryBuffer *I)
1315   : TheMacro(M), Instantiation(I), InstantiationLoc(IL), ExitLoc(EL)
1316 {
1317 }
1318
1319 bool AsmParser::HandleMacroEntry(StringRef Name, SMLoc NameLoc,
1320                                  const Macro *M) {
1321   // Arbitrarily limit macro nesting depth, to match 'as'. We can eliminate
1322   // this, although we should protect against infinite loops.
1323   if (ActiveMacros.size() == 20)
1324     return TokError("macros cannot be nested more than 20 levels deep");
1325
1326   // Parse the macro instantiation arguments.
1327   std::vector<std::vector<AsmToken> > MacroArguments;
1328   MacroArguments.push_back(std::vector<AsmToken>());
1329   unsigned ParenLevel = 0;
1330   for (;;) {
1331     if (Lexer.is(AsmToken::Eof))
1332       return TokError("unexpected token in macro instantiation");
1333     if (Lexer.is(AsmToken::EndOfStatement))
1334       break;
1335
1336     // If we aren't inside parentheses and this is a comma, start a new token
1337     // list.
1338     if (ParenLevel == 0 && Lexer.is(AsmToken::Comma)) {
1339       MacroArguments.push_back(std::vector<AsmToken>());
1340     } else {
1341       // Adjust the current parentheses level.
1342       if (Lexer.is(AsmToken::LParen))
1343         ++ParenLevel;
1344       else if (Lexer.is(AsmToken::RParen) && ParenLevel)
1345         --ParenLevel;
1346
1347       // Append the token to the current argument list.
1348       MacroArguments.back().push_back(getTok());
1349     }
1350     Lex();
1351   }
1352
1353   // Macro instantiation is lexical, unfortunately. We construct a new buffer
1354   // to hold the macro body with substitutions.
1355   SmallString<256> Buf;
1356   StringRef Body = M->Body;
1357
1358   if (expandMacro(Buf, Body, M->Parameters, MacroArguments, getTok().getLoc()))
1359     return true;
1360
1361   MemoryBuffer *Instantiation =
1362     MemoryBuffer::getMemBufferCopy(Buf.str(), "<instantiation>");
1363
1364   // Create the macro instantiation object and add to the current macro
1365   // instantiation stack.
1366   MacroInstantiation *MI = new MacroInstantiation(M, NameLoc,
1367                                                   getTok().getLoc(),
1368                                                   Instantiation);
1369   ActiveMacros.push_back(MI);
1370
1371   // Jump to the macro instantiation and prime the lexer.
1372   CurBuffer = SrcMgr.AddNewSourceBuffer(MI->Instantiation, SMLoc());
1373   Lexer.setBuffer(SrcMgr.getMemoryBuffer(CurBuffer));
1374   Lex();
1375
1376   return false;
1377 }
1378
1379 void AsmParser::HandleMacroExit() {
1380   // Jump to the EndOfStatement we should return to, and consume it.
1381   JumpToLoc(ActiveMacros.back()->ExitLoc);
1382   Lex();
1383
1384   // Pop the instantiation entry.
1385   delete ActiveMacros.back();
1386   ActiveMacros.pop_back();
1387 }
1388
1389 static void MarkUsed(const MCExpr *Value) {
1390   switch (Value->getKind()) {
1391   case MCExpr::Binary:
1392     MarkUsed(static_cast<const MCBinaryExpr*>(Value)->getLHS());
1393     MarkUsed(static_cast<const MCBinaryExpr*>(Value)->getRHS());
1394     break;
1395   case MCExpr::Target:
1396   case MCExpr::Constant:
1397     break;
1398   case MCExpr::SymbolRef: {
1399     static_cast<const MCSymbolRefExpr*>(Value)->getSymbol().setUsed(true);
1400     break;
1401   }
1402   case MCExpr::Unary:
1403     MarkUsed(static_cast<const MCUnaryExpr*>(Value)->getSubExpr());
1404     break;
1405   }
1406 }
1407
1408 bool AsmParser::ParseAssignment(StringRef Name, bool allow_redef) {
1409   // FIXME: Use better location, we should use proper tokens.
1410   SMLoc EqualLoc = Lexer.getLoc();
1411
1412   const MCExpr *Value;
1413   if (ParseExpression(Value))
1414     return true;
1415
1416   MarkUsed(Value);
1417
1418   if (Lexer.isNot(AsmToken::EndOfStatement))
1419     return TokError("unexpected token in assignment");
1420
1421   // Error on assignment to '.'.
1422   if (Name == ".") {
1423     return Error(EqualLoc, ("assignment to pseudo-symbol '.' is unsupported "
1424                             "(use '.space' or '.org').)"));
1425   }
1426
1427   // Eat the end of statement marker.
1428   Lex();
1429
1430   // Validate that the LHS is allowed to be a variable (either it has not been
1431   // used as a symbol, or it is an absolute symbol).
1432   MCSymbol *Sym = getContext().LookupSymbol(Name);
1433   if (Sym) {
1434     // Diagnose assignment to a label.
1435     //
1436     // FIXME: Diagnostics. Note the location of the definition as a label.
1437     // FIXME: Diagnose assignment to protected identifier (e.g., register name).
1438     if (Sym->isUndefined() && !Sym->isUsed() && !Sym->isVariable())
1439       ; // Allow redefinitions of undefined symbols only used in directives.
1440     else if (!Sym->isUndefined() && (!Sym->isVariable() || !allow_redef))
1441       return Error(EqualLoc, "redefinition of '" + Name + "'");
1442     else if (!Sym->isVariable())
1443       return Error(EqualLoc, "invalid assignment to '" + Name + "'");
1444     else if (!isa<MCConstantExpr>(Sym->getVariableValue()))
1445       return Error(EqualLoc, "invalid reassignment of non-absolute variable '" +
1446                    Name + "'");
1447
1448     // Don't count these checks as uses.
1449     Sym->setUsed(false);
1450   } else
1451     Sym = getContext().GetOrCreateSymbol(Name);
1452
1453   // FIXME: Handle '.'.
1454
1455   // Do the assignment.
1456   Out.EmitAssignment(Sym, Value);
1457
1458   return false;
1459 }
1460
1461 /// ParseIdentifier:
1462 ///   ::= identifier
1463 ///   ::= string
1464 bool AsmParser::ParseIdentifier(StringRef &Res) {
1465   // The assembler has relaxed rules for accepting identifiers, in particular we
1466   // allow things like '.globl $foo', which would normally be separate
1467   // tokens. At this level, we have already lexed so we cannot (currently)
1468   // handle this as a context dependent token, instead we detect adjacent tokens
1469   // and return the combined identifier.
1470   if (Lexer.is(AsmToken::Dollar)) {
1471     SMLoc DollarLoc = getLexer().getLoc();
1472
1473     // Consume the dollar sign, and check for a following identifier.
1474     Lex();
1475     if (Lexer.isNot(AsmToken::Identifier))
1476       return true;
1477
1478     // We have a '$' followed by an identifier, make sure they are adjacent.
1479     if (DollarLoc.getPointer() + 1 != getTok().getLoc().getPointer())
1480       return true;
1481
1482     // Construct the joined identifier and consume the token.
1483     Res = StringRef(DollarLoc.getPointer(),
1484                     getTok().getIdentifier().size() + 1);
1485     Lex();
1486     return false;
1487   }
1488
1489   if (Lexer.isNot(AsmToken::Identifier) &&
1490       Lexer.isNot(AsmToken::String))
1491     return true;
1492
1493   Res = getTok().getIdentifier();
1494
1495   Lex(); // Consume the identifier token.
1496
1497   return false;
1498 }
1499
1500 /// ParseDirectiveSet:
1501 ///   ::= .equ identifier ',' expression
1502 ///   ::= .equiv identifier ',' expression
1503 ///   ::= .set identifier ',' expression
1504 bool AsmParser::ParseDirectiveSet(StringRef IDVal, bool allow_redef) {
1505   StringRef Name;
1506
1507   if (ParseIdentifier(Name))
1508     return TokError("expected identifier after '" + Twine(IDVal) + "'");
1509
1510   if (getLexer().isNot(AsmToken::Comma))
1511     return TokError("unexpected token in '" + Twine(IDVal) + "'");
1512   Lex();
1513
1514   return ParseAssignment(Name, allow_redef);
1515 }
1516
1517 bool AsmParser::ParseEscapedString(std::string &Data) {
1518   assert(getLexer().is(AsmToken::String) && "Unexpected current token!");
1519
1520   Data = "";
1521   StringRef Str = getTok().getStringContents();
1522   for (unsigned i = 0, e = Str.size(); i != e; ++i) {
1523     if (Str[i] != '\\') {
1524       Data += Str[i];
1525       continue;
1526     }
1527
1528     // Recognize escaped characters. Note that this escape semantics currently
1529     // loosely follows Darwin 'as'. Notably, it doesn't support hex escapes.
1530     ++i;
1531     if (i == e)
1532       return TokError("unexpected backslash at end of string");
1533
1534     // Recognize octal sequences.
1535     if ((unsigned) (Str[i] - '0') <= 7) {
1536       // Consume up to three octal characters.
1537       unsigned Value = Str[i] - '0';
1538
1539       if (i + 1 != e && ((unsigned) (Str[i + 1] - '0')) <= 7) {
1540         ++i;
1541         Value = Value * 8 + (Str[i] - '0');
1542
1543         if (i + 1 != e && ((unsigned) (Str[i + 1] - '0')) <= 7) {
1544           ++i;
1545           Value = Value * 8 + (Str[i] - '0');
1546         }
1547       }
1548
1549       if (Value > 255)
1550         return TokError("invalid octal escape sequence (out of range)");
1551
1552       Data += (unsigned char) Value;
1553       continue;
1554     }
1555
1556     // Otherwise recognize individual escapes.
1557     switch (Str[i]) {
1558     default:
1559       // Just reject invalid escape sequences for now.
1560       return TokError("invalid escape sequence (unrecognized character)");
1561
1562     case 'b': Data += '\b'; break;
1563     case 'f': Data += '\f'; break;
1564     case 'n': Data += '\n'; break;
1565     case 'r': Data += '\r'; break;
1566     case 't': Data += '\t'; break;
1567     case '"': Data += '"'; break;
1568     case '\\': Data += '\\'; break;
1569     }
1570   }
1571
1572   return false;
1573 }
1574
1575 /// ParseDirectiveAscii:
1576 ///   ::= ( .ascii | .asciz | .string ) [ "string" ( , "string" )* ]
1577 bool AsmParser::ParseDirectiveAscii(StringRef IDVal, bool ZeroTerminated) {
1578   if (getLexer().isNot(AsmToken::EndOfStatement)) {
1579     CheckForValidSection();
1580
1581     for (;;) {
1582       if (getLexer().isNot(AsmToken::String))
1583         return TokError("expected string in '" + Twine(IDVal) + "' directive");
1584
1585       std::string Data;
1586       if (ParseEscapedString(Data))
1587         return true;
1588
1589       getStreamer().EmitBytes(Data, DEFAULT_ADDRSPACE);
1590       if (ZeroTerminated)
1591         getStreamer().EmitBytes(StringRef("\0", 1), DEFAULT_ADDRSPACE);
1592
1593       Lex();
1594
1595       if (getLexer().is(AsmToken::EndOfStatement))
1596         break;
1597
1598       if (getLexer().isNot(AsmToken::Comma))
1599         return TokError("unexpected token in '" + Twine(IDVal) + "' directive");
1600       Lex();
1601     }
1602   }
1603
1604   Lex();
1605   return false;
1606 }
1607
1608 /// ParseDirectiveValue
1609 ///  ::= (.byte | .short | ... ) [ expression (, expression)* ]
1610 bool AsmParser::ParseDirectiveValue(unsigned Size) {
1611   if (getLexer().isNot(AsmToken::EndOfStatement)) {
1612     CheckForValidSection();
1613
1614     for (;;) {
1615       const MCExpr *Value;
1616       SMLoc ExprLoc = getLexer().getLoc();
1617       if (ParseExpression(Value))
1618         return true;
1619
1620       // Special case constant expressions to match code generator.
1621       if (const MCConstantExpr *MCE = dyn_cast<MCConstantExpr>(Value)) {
1622         assert(Size <= 8 && "Invalid size");
1623         uint64_t IntValue = MCE->getValue();
1624         if (!isUIntN(8 * Size, IntValue) && !isIntN(8 * Size, IntValue))
1625           return Error(ExprLoc, "literal value out of range for directive");
1626         getStreamer().EmitIntValue(IntValue, Size, DEFAULT_ADDRSPACE);
1627       } else
1628         getStreamer().EmitValue(Value, Size, DEFAULT_ADDRSPACE);
1629
1630       if (getLexer().is(AsmToken::EndOfStatement))
1631         break;
1632
1633       // FIXME: Improve diagnostic.
1634       if (getLexer().isNot(AsmToken::Comma))
1635         return TokError("unexpected token in directive");
1636       Lex();
1637     }
1638   }
1639
1640   Lex();
1641   return false;
1642 }
1643
1644 /// ParseDirectiveRealValue
1645 ///  ::= (.single | .double) [ expression (, expression)* ]
1646 bool AsmParser::ParseDirectiveRealValue(const fltSemantics &Semantics) {
1647   if (getLexer().isNot(AsmToken::EndOfStatement)) {
1648     CheckForValidSection();
1649
1650     for (;;) {
1651       // We don't truly support arithmetic on floating point expressions, so we
1652       // have to manually parse unary prefixes.
1653       bool IsNeg = false;
1654       if (getLexer().is(AsmToken::Minus)) {
1655         Lex();
1656         IsNeg = true;
1657       } else if (getLexer().is(AsmToken::Plus))
1658         Lex();
1659
1660       if (getLexer().isNot(AsmToken::Integer) &&
1661           getLexer().isNot(AsmToken::Real) &&
1662           getLexer().isNot(AsmToken::Identifier))
1663         return TokError("unexpected token in directive");
1664
1665       // Convert to an APFloat.
1666       APFloat Value(Semantics);
1667       StringRef IDVal = getTok().getString();
1668       if (getLexer().is(AsmToken::Identifier)) {
1669         if (!IDVal.compare_lower("infinity") || !IDVal.compare_lower("inf"))
1670           Value = APFloat::getInf(Semantics);
1671         else if (!IDVal.compare_lower("nan"))
1672           Value = APFloat::getNaN(Semantics, false, ~0);
1673         else
1674           return TokError("invalid floating point literal");
1675       } else if (Value.convertFromString(IDVal, APFloat::rmNearestTiesToEven) ==
1676           APFloat::opInvalidOp)
1677         return TokError("invalid floating point literal");
1678       if (IsNeg)
1679         Value.changeSign();
1680
1681       // Consume the numeric token.
1682       Lex();
1683
1684       // Emit the value as an integer.
1685       APInt AsInt = Value.bitcastToAPInt();
1686       getStreamer().EmitIntValue(AsInt.getLimitedValue(),
1687                                  AsInt.getBitWidth() / 8, DEFAULT_ADDRSPACE);
1688
1689       if (getLexer().is(AsmToken::EndOfStatement))
1690         break;
1691
1692       if (getLexer().isNot(AsmToken::Comma))
1693         return TokError("unexpected token in directive");
1694       Lex();
1695     }
1696   }
1697
1698   Lex();
1699   return false;
1700 }
1701
1702 /// ParseDirectiveSpace
1703 ///  ::= .space expression [ , expression ]
1704 bool AsmParser::ParseDirectiveSpace() {
1705   CheckForValidSection();
1706
1707   int64_t NumBytes;
1708   if (ParseAbsoluteExpression(NumBytes))
1709     return true;
1710
1711   int64_t FillExpr = 0;
1712   if (getLexer().isNot(AsmToken::EndOfStatement)) {
1713     if (getLexer().isNot(AsmToken::Comma))
1714       return TokError("unexpected token in '.space' directive");
1715     Lex();
1716
1717     if (ParseAbsoluteExpression(FillExpr))
1718       return true;
1719
1720     if (getLexer().isNot(AsmToken::EndOfStatement))
1721       return TokError("unexpected token in '.space' directive");
1722   }
1723
1724   Lex();
1725
1726   if (NumBytes <= 0)
1727     return TokError("invalid number of bytes in '.space' directive");
1728
1729   // FIXME: Sometimes the fill expr is 'nop' if it isn't supplied, instead of 0.
1730   getStreamer().EmitFill(NumBytes, FillExpr, DEFAULT_ADDRSPACE);
1731
1732   return false;
1733 }
1734
1735 /// ParseDirectiveZero
1736 ///  ::= .zero expression
1737 bool AsmParser::ParseDirectiveZero() {
1738   CheckForValidSection();
1739
1740   int64_t NumBytes;
1741   if (ParseAbsoluteExpression(NumBytes))
1742     return true;
1743
1744   int64_t Val = 0;
1745   if (getLexer().is(AsmToken::Comma)) {
1746     Lex();
1747     if (ParseAbsoluteExpression(Val))
1748       return true;
1749   }
1750
1751   if (getLexer().isNot(AsmToken::EndOfStatement))
1752     return TokError("unexpected token in '.zero' directive");
1753
1754   Lex();
1755
1756   getStreamer().EmitFill(NumBytes, Val, DEFAULT_ADDRSPACE);
1757
1758   return false;
1759 }
1760
1761 /// ParseDirectiveFill
1762 ///  ::= .fill expression , expression , expression
1763 bool AsmParser::ParseDirectiveFill() {
1764   CheckForValidSection();
1765
1766   int64_t NumValues;
1767   if (ParseAbsoluteExpression(NumValues))
1768     return true;
1769
1770   if (getLexer().isNot(AsmToken::Comma))
1771     return TokError("unexpected token in '.fill' directive");
1772   Lex();
1773
1774   int64_t FillSize;
1775   if (ParseAbsoluteExpression(FillSize))
1776     return true;
1777
1778   if (getLexer().isNot(AsmToken::Comma))
1779     return TokError("unexpected token in '.fill' directive");
1780   Lex();
1781
1782   int64_t FillExpr;
1783   if (ParseAbsoluteExpression(FillExpr))
1784     return true;
1785
1786   if (getLexer().isNot(AsmToken::EndOfStatement))
1787     return TokError("unexpected token in '.fill' directive");
1788
1789   Lex();
1790
1791   if (FillSize != 1 && FillSize != 2 && FillSize != 4 && FillSize != 8)
1792     return TokError("invalid '.fill' size, expected 1, 2, 4, or 8");
1793
1794   for (uint64_t i = 0, e = NumValues; i != e; ++i)
1795     getStreamer().EmitIntValue(FillExpr, FillSize, DEFAULT_ADDRSPACE);
1796
1797   return false;
1798 }
1799
1800 /// ParseDirectiveOrg
1801 ///  ::= .org expression [ , expression ]
1802 bool AsmParser::ParseDirectiveOrg() {
1803   CheckForValidSection();
1804
1805   const MCExpr *Offset;
1806   if (ParseExpression(Offset))
1807     return true;
1808
1809   // Parse optional fill expression.
1810   int64_t FillExpr = 0;
1811   if (getLexer().isNot(AsmToken::EndOfStatement)) {
1812     if (getLexer().isNot(AsmToken::Comma))
1813       return TokError("unexpected token in '.org' directive");
1814     Lex();
1815
1816     if (ParseAbsoluteExpression(FillExpr))
1817       return true;
1818
1819     if (getLexer().isNot(AsmToken::EndOfStatement))
1820       return TokError("unexpected token in '.org' directive");
1821   }
1822
1823   Lex();
1824
1825   // FIXME: Only limited forms of relocatable expressions are accepted here, it
1826   // has to be relative to the current section.
1827   getStreamer().EmitValueToOffset(Offset, FillExpr);
1828
1829   return false;
1830 }
1831
1832 /// ParseDirectiveAlign
1833 ///  ::= {.align, ...} expression [ , expression [ , expression ]]
1834 bool AsmParser::ParseDirectiveAlign(bool IsPow2, unsigned ValueSize) {
1835   CheckForValidSection();
1836
1837   SMLoc AlignmentLoc = getLexer().getLoc();
1838   int64_t Alignment;
1839   if (ParseAbsoluteExpression(Alignment))
1840     return true;
1841
1842   SMLoc MaxBytesLoc;
1843   bool HasFillExpr = false;
1844   int64_t FillExpr = 0;
1845   int64_t MaxBytesToFill = 0;
1846   if (getLexer().isNot(AsmToken::EndOfStatement)) {
1847     if (getLexer().isNot(AsmToken::Comma))
1848       return TokError("unexpected token in directive");
1849     Lex();
1850
1851     // The fill expression can be omitted while specifying a maximum number of
1852     // alignment bytes, e.g:
1853     //  .align 3,,4
1854     if (getLexer().isNot(AsmToken::Comma)) {
1855       HasFillExpr = true;
1856       if (ParseAbsoluteExpression(FillExpr))
1857         return true;
1858     }
1859
1860     if (getLexer().isNot(AsmToken::EndOfStatement)) {
1861       if (getLexer().isNot(AsmToken::Comma))
1862         return TokError("unexpected token in directive");
1863       Lex();
1864
1865       MaxBytesLoc = getLexer().getLoc();
1866       if (ParseAbsoluteExpression(MaxBytesToFill))
1867         return true;
1868
1869       if (getLexer().isNot(AsmToken::EndOfStatement))
1870         return TokError("unexpected token in directive");
1871     }
1872   }
1873
1874   Lex();
1875
1876   if (!HasFillExpr)
1877     FillExpr = 0;
1878
1879   // Compute alignment in bytes.
1880   if (IsPow2) {
1881     // FIXME: Diagnose overflow.
1882     if (Alignment >= 32) {
1883       Error(AlignmentLoc, "invalid alignment value");
1884       Alignment = 31;
1885     }
1886
1887     Alignment = 1ULL << Alignment;
1888   }
1889
1890   // Diagnose non-sensical max bytes to align.
1891   if (MaxBytesLoc.isValid()) {
1892     if (MaxBytesToFill < 1) {
1893       Error(MaxBytesLoc, "alignment directive can never be satisfied in this "
1894             "many bytes, ignoring maximum bytes expression");
1895       MaxBytesToFill = 0;
1896     }
1897
1898     if (MaxBytesToFill >= Alignment) {
1899       Warning(MaxBytesLoc, "maximum bytes expression exceeds alignment and "
1900               "has no effect");
1901       MaxBytesToFill = 0;
1902     }
1903   }
1904
1905   // Check whether we should use optimal code alignment for this .align
1906   // directive.
1907   bool UseCodeAlign = getStreamer().getCurrentSection()->UseCodeAlign();
1908   if ((!HasFillExpr || Lexer.getMAI().getTextAlignFillValue() == FillExpr) &&
1909       ValueSize == 1 && UseCodeAlign) {
1910     getStreamer().EmitCodeAlignment(Alignment, MaxBytesToFill);
1911   } else {
1912     // FIXME: Target specific behavior about how the "extra" bytes are filled.
1913     getStreamer().EmitValueToAlignment(Alignment, FillExpr, ValueSize,
1914                                        MaxBytesToFill);
1915   }
1916
1917   return false;
1918 }
1919
1920 /// ParseDirectiveSymbolAttribute
1921 ///  ::= { ".globl", ".weak", ... } [ identifier ( , identifier )* ]
1922 bool AsmParser::ParseDirectiveSymbolAttribute(MCSymbolAttr Attr) {
1923   if (getLexer().isNot(AsmToken::EndOfStatement)) {
1924     for (;;) {
1925       StringRef Name;
1926
1927       if (ParseIdentifier(Name))
1928         return TokError("expected identifier in directive");
1929
1930       MCSymbol *Sym = getContext().GetOrCreateSymbol(Name);
1931
1932       getStreamer().EmitSymbolAttribute(Sym, Attr);
1933
1934       if (getLexer().is(AsmToken::EndOfStatement))
1935         break;
1936
1937       if (getLexer().isNot(AsmToken::Comma))
1938         return TokError("unexpected token in directive");
1939       Lex();
1940     }
1941   }
1942
1943   Lex();
1944   return false;
1945 }
1946
1947 /// ParseDirectiveComm
1948 ///  ::= ( .comm | .lcomm ) identifier , size_expression [ , align_expression ]
1949 bool AsmParser::ParseDirectiveComm(bool IsLocal) {
1950   CheckForValidSection();
1951
1952   SMLoc IDLoc = getLexer().getLoc();
1953   StringRef Name;
1954   if (ParseIdentifier(Name))
1955     return TokError("expected identifier in directive");
1956
1957   // Handle the identifier as the key symbol.
1958   MCSymbol *Sym = getContext().GetOrCreateSymbol(Name);
1959
1960   if (getLexer().isNot(AsmToken::Comma))
1961     return TokError("unexpected token in directive");
1962   Lex();
1963
1964   int64_t Size;
1965   SMLoc SizeLoc = getLexer().getLoc();
1966   if (ParseAbsoluteExpression(Size))
1967     return true;
1968
1969   int64_t Pow2Alignment = 0;
1970   SMLoc Pow2AlignmentLoc;
1971   if (getLexer().is(AsmToken::Comma)) {
1972     Lex();
1973     Pow2AlignmentLoc = getLexer().getLoc();
1974     if (ParseAbsoluteExpression(Pow2Alignment))
1975       return true;
1976
1977     // If this target takes alignments in bytes (not log) validate and convert.
1978     if (Lexer.getMAI().getAlignmentIsInBytes()) {
1979       if (!isPowerOf2_64(Pow2Alignment))
1980         return Error(Pow2AlignmentLoc, "alignment must be a power of 2");
1981       Pow2Alignment = Log2_64(Pow2Alignment);
1982     }
1983   }
1984
1985   if (getLexer().isNot(AsmToken::EndOfStatement))
1986     return TokError("unexpected token in '.comm' or '.lcomm' directive");
1987
1988   Lex();
1989
1990   // NOTE: a size of zero for a .comm should create a undefined symbol
1991   // but a size of .lcomm creates a bss symbol of size zero.
1992   if (Size < 0)
1993     return Error(SizeLoc, "invalid '.comm' or '.lcomm' directive size, can't "
1994                  "be less than zero");
1995
1996   // NOTE: The alignment in the directive is a power of 2 value, the assembler
1997   // may internally end up wanting an alignment in bytes.
1998   // FIXME: Diagnose overflow.
1999   if (Pow2Alignment < 0)
2000     return Error(Pow2AlignmentLoc, "invalid '.comm' or '.lcomm' directive "
2001                  "alignment, can't be less than zero");
2002
2003   if (!Sym->isUndefined())
2004     return Error(IDLoc, "invalid symbol redefinition");
2005
2006   // '.lcomm' is equivalent to '.zerofill'.
2007   // Create the Symbol as a common or local common with Size and Pow2Alignment
2008   if (IsLocal) {
2009     getStreamer().EmitZerofill(Ctx.getMachOSection(
2010                                  "__DATA", "__bss", MCSectionMachO::S_ZEROFILL,
2011                                  0, SectionKind::getBSS()),
2012                                Sym, Size, 1 << Pow2Alignment);
2013     return false;
2014   }
2015
2016   getStreamer().EmitCommonSymbol(Sym, Size, 1 << Pow2Alignment);
2017   return false;
2018 }
2019
2020 /// ParseDirectiveAbort
2021 ///  ::= .abort [... message ...]
2022 bool AsmParser::ParseDirectiveAbort() {
2023   // FIXME: Use loc from directive.
2024   SMLoc Loc = getLexer().getLoc();
2025
2026   StringRef Str = ParseStringToEndOfStatement();
2027   if (getLexer().isNot(AsmToken::EndOfStatement))
2028     return TokError("unexpected token in '.abort' directive");
2029
2030   Lex();
2031
2032   if (Str.empty())
2033     Error(Loc, ".abort detected. Assembly stopping.");
2034   else
2035     Error(Loc, ".abort '" + Str + "' detected. Assembly stopping.");
2036   // FIXME: Actually abort assembly here.
2037
2038   return false;
2039 }
2040
2041 /// ParseDirectiveInclude
2042 ///  ::= .include "filename"
2043 bool AsmParser::ParseDirectiveInclude() {
2044   if (getLexer().isNot(AsmToken::String))
2045     return TokError("expected string in '.include' directive");
2046
2047   std::string Filename = getTok().getString();
2048   SMLoc IncludeLoc = getLexer().getLoc();
2049   Lex();
2050
2051   if (getLexer().isNot(AsmToken::EndOfStatement))
2052     return TokError("unexpected token in '.include' directive");
2053
2054   // Strip the quotes.
2055   Filename = Filename.substr(1, Filename.size()-2);
2056
2057   // Attempt to switch the lexer to the included file before consuming the end
2058   // of statement to avoid losing it when we switch.
2059   if (EnterIncludeFile(Filename)) {
2060     Error(IncludeLoc, "Could not find include file '" + Filename + "'");
2061     return true;
2062   }
2063
2064   return false;
2065 }
2066
2067 /// ParseDirectiveIf
2068 /// ::= .if expression
2069 bool AsmParser::ParseDirectiveIf(SMLoc DirectiveLoc) {
2070   TheCondStack.push_back(TheCondState);
2071   TheCondState.TheCond = AsmCond::IfCond;
2072   if(TheCondState.Ignore) {
2073     EatToEndOfStatement();
2074   }
2075   else {
2076     int64_t ExprValue;
2077     if (ParseAbsoluteExpression(ExprValue))
2078       return true;
2079
2080     if (getLexer().isNot(AsmToken::EndOfStatement))
2081       return TokError("unexpected token in '.if' directive");
2082
2083     Lex();
2084
2085     TheCondState.CondMet = ExprValue;
2086     TheCondState.Ignore = !TheCondState.CondMet;
2087   }
2088
2089   return false;
2090 }
2091
2092 bool AsmParser::ParseDirectiveIfdef(SMLoc DirectiveLoc, bool expect_defined) {
2093   StringRef Name;
2094   TheCondStack.push_back(TheCondState);
2095   TheCondState.TheCond = AsmCond::IfCond;
2096
2097   if (TheCondState.Ignore) {
2098     EatToEndOfStatement();
2099   } else {
2100     if (ParseIdentifier(Name))
2101       return TokError("expected identifier after '.ifdef'");
2102
2103     Lex();
2104
2105     MCSymbol *Sym = getContext().LookupSymbol(Name);
2106
2107     if (expect_defined)
2108       TheCondState.CondMet = (Sym != NULL && !Sym->isUndefined());
2109     else
2110       TheCondState.CondMet = (Sym == NULL || Sym->isUndefined());
2111     TheCondState.Ignore = !TheCondState.CondMet;
2112   }
2113
2114   return false;
2115 }
2116
2117 /// ParseDirectiveElseIf
2118 /// ::= .elseif expression
2119 bool AsmParser::ParseDirectiveElseIf(SMLoc DirectiveLoc) {
2120   if (TheCondState.TheCond != AsmCond::IfCond &&
2121       TheCondState.TheCond != AsmCond::ElseIfCond)
2122       Error(DirectiveLoc, "Encountered a .elseif that doesn't follow a .if or "
2123                           " an .elseif");
2124   TheCondState.TheCond = AsmCond::ElseIfCond;
2125
2126   bool LastIgnoreState = false;
2127   if (!TheCondStack.empty())
2128       LastIgnoreState = TheCondStack.back().Ignore;
2129   if (LastIgnoreState || TheCondState.CondMet) {
2130     TheCondState.Ignore = true;
2131     EatToEndOfStatement();
2132   }
2133   else {
2134     int64_t ExprValue;
2135     if (ParseAbsoluteExpression(ExprValue))
2136       return true;
2137
2138     if (getLexer().isNot(AsmToken::EndOfStatement))
2139       return TokError("unexpected token in '.elseif' directive");
2140
2141     Lex();
2142     TheCondState.CondMet = ExprValue;
2143     TheCondState.Ignore = !TheCondState.CondMet;
2144   }
2145
2146   return false;
2147 }
2148
2149 /// ParseDirectiveElse
2150 /// ::= .else
2151 bool AsmParser::ParseDirectiveElse(SMLoc DirectiveLoc) {
2152   if (getLexer().isNot(AsmToken::EndOfStatement))
2153     return TokError("unexpected token in '.else' directive");
2154
2155   Lex();
2156
2157   if (TheCondState.TheCond != AsmCond::IfCond &&
2158       TheCondState.TheCond != AsmCond::ElseIfCond)
2159       Error(DirectiveLoc, "Encountered a .else that doesn't follow a .if or an "
2160                           ".elseif");
2161   TheCondState.TheCond = AsmCond::ElseCond;
2162   bool LastIgnoreState = false;
2163   if (!TheCondStack.empty())
2164     LastIgnoreState = TheCondStack.back().Ignore;
2165   if (LastIgnoreState || TheCondState.CondMet)
2166     TheCondState.Ignore = true;
2167   else
2168     TheCondState.Ignore = false;
2169
2170   return false;
2171 }
2172
2173 /// ParseDirectiveEndIf
2174 /// ::= .endif
2175 bool AsmParser::ParseDirectiveEndIf(SMLoc DirectiveLoc) {
2176   if (getLexer().isNot(AsmToken::EndOfStatement))
2177     return TokError("unexpected token in '.endif' directive");
2178
2179   Lex();
2180
2181   if ((TheCondState.TheCond == AsmCond::NoCond) ||
2182       TheCondStack.empty())
2183     Error(DirectiveLoc, "Encountered a .endif that doesn't follow a .if or "
2184                         ".else");
2185   if (!TheCondStack.empty()) {
2186     TheCondState = TheCondStack.back();
2187     TheCondStack.pop_back();
2188   }
2189
2190   return false;
2191 }
2192
2193 /// ParseDirectiveFile
2194 /// ::= .file [number] string
2195 bool GenericAsmParser::ParseDirectiveFile(StringRef, SMLoc DirectiveLoc) {
2196   // FIXME: I'm not sure what this is.
2197   int64_t FileNumber = -1;
2198   SMLoc FileNumberLoc = getLexer().getLoc();
2199   if (getLexer().is(AsmToken::Integer)) {
2200     FileNumber = getTok().getIntVal();
2201     Lex();
2202
2203     if (FileNumber < 1)
2204       return TokError("file number less than one");
2205   }
2206
2207   if (getLexer().isNot(AsmToken::String))
2208     return TokError("unexpected token in '.file' directive");
2209
2210   StringRef Filename = getTok().getString();
2211   Filename = Filename.substr(1, Filename.size()-2);
2212   Lex();
2213
2214   if (getLexer().isNot(AsmToken::EndOfStatement))
2215     return TokError("unexpected token in '.file' directive");
2216
2217   if (FileNumber == -1)
2218     getStreamer().EmitFileDirective(Filename);
2219   else {
2220     if (getStreamer().EmitDwarfFileDirective(FileNumber, Filename))
2221       Error(FileNumberLoc, "file number already allocated");
2222   }
2223
2224   return false;
2225 }
2226
2227 /// ParseDirectiveLine
2228 /// ::= .line [number]
2229 bool GenericAsmParser::ParseDirectiveLine(StringRef, SMLoc DirectiveLoc) {
2230   if (getLexer().isNot(AsmToken::EndOfStatement)) {
2231     if (getLexer().isNot(AsmToken::Integer))
2232       return TokError("unexpected token in '.line' directive");
2233
2234     int64_t LineNumber = getTok().getIntVal();
2235     (void) LineNumber;
2236     Lex();
2237
2238     // FIXME: Do something with the .line.
2239   }
2240
2241   if (getLexer().isNot(AsmToken::EndOfStatement))
2242     return TokError("unexpected token in '.line' directive");
2243
2244   return false;
2245 }
2246
2247
2248 /// ParseDirectiveLoc
2249 /// ::= .loc FileNumber [LineNumber] [ColumnPos] [basic_block] [prologue_end]
2250 ///                                [epilogue_begin] [is_stmt VALUE] [isa VALUE]
2251 /// The first number is a file number, must have been previously assigned with
2252 /// a .file directive, the second number is the line number and optionally the
2253 /// third number is a column position (zero if not specified).  The remaining
2254 /// optional items are .loc sub-directives.
2255 bool GenericAsmParser::ParseDirectiveLoc(StringRef, SMLoc DirectiveLoc) {
2256
2257   if (getLexer().isNot(AsmToken::Integer))
2258     return TokError("unexpected token in '.loc' directive");
2259   int64_t FileNumber = getTok().getIntVal();
2260   if (FileNumber < 1)
2261     return TokError("file number less than one in '.loc' directive");
2262   if (!getContext().isValidDwarfFileNumber(FileNumber))
2263     return TokError("unassigned file number in '.loc' directive");
2264   Lex();
2265
2266   int64_t LineNumber = 0;
2267   if (getLexer().is(AsmToken::Integer)) {
2268     LineNumber = getTok().getIntVal();
2269     if (LineNumber < 1)
2270       return TokError("line number less than one in '.loc' directive");
2271     Lex();
2272   }
2273
2274   int64_t ColumnPos = 0;
2275   if (getLexer().is(AsmToken::Integer)) {
2276     ColumnPos = getTok().getIntVal();
2277     if (ColumnPos < 0)
2278       return TokError("column position less than zero in '.loc' directive");
2279     Lex();
2280   }
2281
2282   unsigned Flags = DWARF2_LINE_DEFAULT_IS_STMT ? DWARF2_FLAG_IS_STMT : 0;
2283   unsigned Isa = 0;
2284   int64_t Discriminator = 0;
2285   if (getLexer().isNot(AsmToken::EndOfStatement)) {
2286     for (;;) {
2287       if (getLexer().is(AsmToken::EndOfStatement))
2288         break;
2289
2290       StringRef Name;
2291       SMLoc Loc = getTok().getLoc();
2292       if (getParser().ParseIdentifier(Name))
2293         return TokError("unexpected token in '.loc' directive");
2294
2295       if (Name == "basic_block")
2296         Flags |= DWARF2_FLAG_BASIC_BLOCK;
2297       else if (Name == "prologue_end")
2298         Flags |= DWARF2_FLAG_PROLOGUE_END;
2299       else if (Name == "epilogue_begin")
2300         Flags |= DWARF2_FLAG_EPILOGUE_BEGIN;
2301       else if (Name == "is_stmt") {
2302         SMLoc Loc = getTok().getLoc();
2303         const MCExpr *Value;
2304         if (getParser().ParseExpression(Value))
2305           return true;
2306         // The expression must be the constant 0 or 1.
2307         if (const MCConstantExpr *MCE = dyn_cast<MCConstantExpr>(Value)) {
2308           int Value = MCE->getValue();
2309           if (Value == 0)
2310             Flags &= ~DWARF2_FLAG_IS_STMT;
2311           else if (Value == 1)
2312             Flags |= DWARF2_FLAG_IS_STMT;
2313           else
2314             return Error(Loc, "is_stmt value not 0 or 1");
2315         }
2316         else {
2317           return Error(Loc, "is_stmt value not the constant value of 0 or 1");
2318         }
2319       }
2320       else if (Name == "isa") {
2321         SMLoc Loc = getTok().getLoc();
2322         const MCExpr *Value;
2323         if (getParser().ParseExpression(Value))
2324           return true;
2325         // The expression must be a constant greater or equal to 0.
2326         if (const MCConstantExpr *MCE = dyn_cast<MCConstantExpr>(Value)) {
2327           int Value = MCE->getValue();
2328           if (Value < 0)
2329             return Error(Loc, "isa number less than zero");
2330           Isa = Value;
2331         }
2332         else {
2333           return Error(Loc, "isa number not a constant value");
2334         }
2335       }
2336       else if (Name == "discriminator") {
2337         if (getParser().ParseAbsoluteExpression(Discriminator))
2338           return true;
2339       }
2340       else {
2341         return Error(Loc, "unknown sub-directive in '.loc' directive");
2342       }
2343
2344       if (getLexer().is(AsmToken::EndOfStatement))
2345         break;
2346     }
2347   }
2348
2349   getStreamer().EmitDwarfLocDirective(FileNumber, LineNumber, ColumnPos, Flags,
2350                                       Isa, Discriminator, StringRef());
2351
2352   return false;
2353 }
2354
2355 /// ParseDirectiveStabs
2356 /// ::= .stabs string, number, number, number
2357 bool GenericAsmParser::ParseDirectiveStabs(StringRef Directive,
2358                                            SMLoc DirectiveLoc) {
2359   return TokError("unsupported directive '" + Directive + "'");
2360 }
2361
2362 /// ParseDirectiveCFISections
2363 /// ::= .cfi_sections section [, section]
2364 bool GenericAsmParser::ParseDirectiveCFISections(StringRef,
2365                                                  SMLoc DirectiveLoc) {
2366   StringRef Name;
2367   bool EH = false;
2368   bool Debug = false;
2369
2370   if (getParser().ParseIdentifier(Name))
2371     return TokError("Expected an identifier");
2372
2373   if (Name == ".eh_frame")
2374     EH = true;
2375   else if (Name == ".debug_frame")
2376     Debug = true;
2377
2378   if (getLexer().is(AsmToken::Comma)) {
2379     Lex();
2380
2381     if (getParser().ParseIdentifier(Name))
2382       return TokError("Expected an identifier");
2383
2384     if (Name == ".eh_frame")
2385       EH = true;
2386     else if (Name == ".debug_frame")
2387       Debug = true;
2388   }
2389
2390   getStreamer().EmitCFISections(EH, Debug);
2391
2392   return false;
2393 }
2394
2395 /// ParseDirectiveCFIStartProc
2396 /// ::= .cfi_startproc
2397 bool GenericAsmParser::ParseDirectiveCFIStartProc(StringRef,
2398                                                   SMLoc DirectiveLoc) {
2399   getStreamer().EmitCFIStartProc();
2400   return false;
2401 }
2402
2403 /// ParseDirectiveCFIEndProc
2404 /// ::= .cfi_endproc
2405 bool GenericAsmParser::ParseDirectiveCFIEndProc(StringRef, SMLoc DirectiveLoc) {
2406   getStreamer().EmitCFIEndProc();
2407   return false;
2408 }
2409
2410 /// ParseRegisterOrRegisterNumber - parse register name or number.
2411 bool GenericAsmParser::ParseRegisterOrRegisterNumber(int64_t &Register,
2412                                                      SMLoc DirectiveLoc) {
2413   unsigned RegNo;
2414
2415   if (getLexer().isNot(AsmToken::Integer)) {
2416     if (getParser().getTargetParser().ParseRegister(RegNo, DirectiveLoc,
2417       DirectiveLoc))
2418       return true;
2419     Register = getContext().getTargetAsmInfo().getDwarfRegNum(RegNo, true);
2420   } else
2421     return getParser().ParseAbsoluteExpression(Register);
2422
2423   return false;
2424 }
2425
2426 /// ParseDirectiveCFIDefCfa
2427 /// ::= .cfi_def_cfa register,  offset
2428 bool GenericAsmParser::ParseDirectiveCFIDefCfa(StringRef,
2429                                                SMLoc DirectiveLoc) {
2430   int64_t Register = 0;
2431   if (ParseRegisterOrRegisterNumber(Register, DirectiveLoc))
2432     return true;
2433
2434   if (getLexer().isNot(AsmToken::Comma))
2435     return TokError("unexpected token in directive");
2436   Lex();
2437
2438   int64_t Offset = 0;
2439   if (getParser().ParseAbsoluteExpression(Offset))
2440     return true;
2441
2442   getStreamer().EmitCFIDefCfa(Register, Offset);
2443   return false;
2444 }
2445
2446 /// ParseDirectiveCFIDefCfaOffset
2447 /// ::= .cfi_def_cfa_offset offset
2448 bool GenericAsmParser::ParseDirectiveCFIDefCfaOffset(StringRef,
2449                                                      SMLoc DirectiveLoc) {
2450   int64_t Offset = 0;
2451   if (getParser().ParseAbsoluteExpression(Offset))
2452     return true;
2453
2454   getStreamer().EmitCFIDefCfaOffset(Offset);
2455   return false;
2456 }
2457
2458 /// ParseDirectiveCFIAdjustCfaOffset
2459 /// ::= .cfi_adjust_cfa_offset adjustment
2460 bool GenericAsmParser::ParseDirectiveCFIAdjustCfaOffset(StringRef,
2461                                                         SMLoc DirectiveLoc) {
2462   int64_t Adjustment = 0;
2463   if (getParser().ParseAbsoluteExpression(Adjustment))
2464     return true;
2465
2466   getStreamer().EmitCFIAdjustCfaOffset(Adjustment);
2467   return false;
2468 }
2469
2470 /// ParseDirectiveCFIDefCfaRegister
2471 /// ::= .cfi_def_cfa_register register
2472 bool GenericAsmParser::ParseDirectiveCFIDefCfaRegister(StringRef,
2473                                                        SMLoc DirectiveLoc) {
2474   int64_t Register = 0;
2475   if (ParseRegisterOrRegisterNumber(Register, DirectiveLoc))
2476     return true;
2477
2478   getStreamer().EmitCFIDefCfaRegister(Register);
2479   return false;
2480 }
2481
2482 /// ParseDirectiveCFIOffset
2483 /// ::= .cfi_offset register, offset
2484 bool GenericAsmParser::ParseDirectiveCFIOffset(StringRef, SMLoc DirectiveLoc) {
2485   int64_t Register = 0;
2486   int64_t Offset = 0;
2487
2488   if (ParseRegisterOrRegisterNumber(Register, DirectiveLoc))
2489     return true;
2490
2491   if (getLexer().isNot(AsmToken::Comma))
2492     return TokError("unexpected token in directive");
2493   Lex();
2494
2495   if (getParser().ParseAbsoluteExpression(Offset))
2496     return true;
2497
2498   getStreamer().EmitCFIOffset(Register, Offset);
2499   return false;
2500 }
2501
2502 /// ParseDirectiveCFIRelOffset
2503 /// ::= .cfi_rel_offset register, offset
2504 bool GenericAsmParser::ParseDirectiveCFIRelOffset(StringRef,
2505                                                   SMLoc DirectiveLoc) {
2506   int64_t Register = 0;
2507
2508   if (ParseRegisterOrRegisterNumber(Register, DirectiveLoc))
2509     return true;
2510
2511   if (getLexer().isNot(AsmToken::Comma))
2512     return TokError("unexpected token in directive");
2513   Lex();
2514
2515   int64_t Offset = 0;
2516   if (getParser().ParseAbsoluteExpression(Offset))
2517     return true;
2518
2519   getStreamer().EmitCFIRelOffset(Register, Offset);
2520   return false;
2521 }
2522
2523 static bool isValidEncoding(int64_t Encoding) {
2524   if (Encoding & ~0xff)
2525     return false;
2526
2527   if (Encoding == dwarf::DW_EH_PE_omit)
2528     return true;
2529
2530   const unsigned Format = Encoding & 0xf;
2531   if (Format != dwarf::DW_EH_PE_absptr && Format != dwarf::DW_EH_PE_udata2 &&
2532       Format != dwarf::DW_EH_PE_udata4 && Format != dwarf::DW_EH_PE_udata8 &&
2533       Format != dwarf::DW_EH_PE_sdata2 && Format != dwarf::DW_EH_PE_sdata4 &&
2534       Format != dwarf::DW_EH_PE_sdata8 && Format != dwarf::DW_EH_PE_signed)
2535     return false;
2536
2537   const unsigned Application = Encoding & 0x70;
2538   if (Application != dwarf::DW_EH_PE_absptr &&
2539       Application != dwarf::DW_EH_PE_pcrel)
2540     return false;
2541
2542   return true;
2543 }
2544
2545 /// ParseDirectiveCFIPersonalityOrLsda
2546 /// ::= .cfi_personality encoding, [symbol_name]
2547 /// ::= .cfi_lsda encoding, [symbol_name]
2548 bool GenericAsmParser::ParseDirectiveCFIPersonalityOrLsda(StringRef IDVal,
2549                                                     SMLoc DirectiveLoc) {
2550   int64_t Encoding = 0;
2551   if (getParser().ParseAbsoluteExpression(Encoding))
2552     return true;
2553   if (Encoding == dwarf::DW_EH_PE_omit)
2554     return false;
2555
2556   if (!isValidEncoding(Encoding))
2557     return TokError("unsupported encoding.");
2558
2559   if (getLexer().isNot(AsmToken::Comma))
2560     return TokError("unexpected token in directive");
2561   Lex();
2562
2563   StringRef Name;
2564   if (getParser().ParseIdentifier(Name))
2565     return TokError("expected identifier in directive");
2566
2567   MCSymbol *Sym = getContext().GetOrCreateSymbol(Name);
2568
2569   if (IDVal == ".cfi_personality")
2570     getStreamer().EmitCFIPersonality(Sym, Encoding);
2571   else {
2572     assert(IDVal == ".cfi_lsda");
2573     getStreamer().EmitCFILsda(Sym, Encoding);
2574   }
2575   return false;
2576 }
2577
2578 /// ParseDirectiveCFIRememberState
2579 /// ::= .cfi_remember_state
2580 bool GenericAsmParser::ParseDirectiveCFIRememberState(StringRef IDVal,
2581                                                       SMLoc DirectiveLoc) {
2582   getStreamer().EmitCFIRememberState();
2583   return false;
2584 }
2585
2586 /// ParseDirectiveCFIRestoreState
2587 /// ::= .cfi_remember_state
2588 bool GenericAsmParser::ParseDirectiveCFIRestoreState(StringRef IDVal,
2589                                                      SMLoc DirectiveLoc) {
2590   getStreamer().EmitCFIRestoreState();
2591   return false;
2592 }
2593
2594 /// ParseDirectiveCFISameValue
2595 /// ::= .cfi_same_value register
2596 bool GenericAsmParser::ParseDirectiveCFISameValue(StringRef IDVal,
2597                                                   SMLoc DirectiveLoc) {
2598   int64_t Register = 0;
2599
2600   if (ParseRegisterOrRegisterNumber(Register, DirectiveLoc))
2601     return true;
2602
2603   getStreamer().EmitCFISameValue(Register);
2604
2605   return false;
2606 }
2607
2608 /// ParseDirectiveMacrosOnOff
2609 /// ::= .macros_on
2610 /// ::= .macros_off
2611 bool GenericAsmParser::ParseDirectiveMacrosOnOff(StringRef Directive,
2612                                                  SMLoc DirectiveLoc) {
2613   if (getLexer().isNot(AsmToken::EndOfStatement))
2614     return Error(getLexer().getLoc(),
2615                  "unexpected token in '" + Directive + "' directive");
2616
2617   getParser().MacrosEnabled = Directive == ".macros_on";
2618
2619   return false;
2620 }
2621
2622 /// ParseDirectiveMacro
2623 /// ::= .macro name [parameters]
2624 bool GenericAsmParser::ParseDirectiveMacro(StringRef Directive,
2625                                            SMLoc DirectiveLoc) {
2626   StringRef Name;
2627   if (getParser().ParseIdentifier(Name))
2628     return TokError("expected identifier in directive");
2629
2630   std::vector<StringRef> Parameters;
2631   if (getLexer().isNot(AsmToken::EndOfStatement)) {
2632     for(;;) {
2633       StringRef Parameter;
2634       if (getParser().ParseIdentifier(Parameter))
2635         return TokError("expected identifier in directive");
2636       Parameters.push_back(Parameter);
2637
2638       if (getLexer().isNot(AsmToken::Comma))
2639         break;
2640       Lex();
2641     }
2642   }
2643
2644   if (getLexer().isNot(AsmToken::EndOfStatement))
2645     return TokError("unexpected token in '.macro' directive");
2646
2647   // Eat the end of statement.
2648   Lex();
2649
2650   AsmToken EndToken, StartToken = getTok();
2651
2652   // Lex the macro definition.
2653   for (;;) {
2654     // Check whether we have reached the end of the file.
2655     if (getLexer().is(AsmToken::Eof))
2656       return Error(DirectiveLoc, "no matching '.endmacro' in definition");
2657
2658     // Otherwise, check whether we have reach the .endmacro.
2659     if (getLexer().is(AsmToken::Identifier) &&
2660         (getTok().getIdentifier() == ".endm" ||
2661          getTok().getIdentifier() == ".endmacro")) {
2662       EndToken = getTok();
2663       Lex();
2664       if (getLexer().isNot(AsmToken::EndOfStatement))
2665         return TokError("unexpected token in '" + EndToken.getIdentifier() +
2666                         "' directive");
2667       break;
2668     }
2669
2670     // Otherwise, scan til the end of the statement.
2671     getParser().EatToEndOfStatement();
2672   }
2673
2674   if (getParser().MacroMap.lookup(Name)) {
2675     return Error(DirectiveLoc, "macro '" + Name + "' is already defined");
2676   }
2677
2678   const char *BodyStart = StartToken.getLoc().getPointer();
2679   const char *BodyEnd = EndToken.getLoc().getPointer();
2680   StringRef Body = StringRef(BodyStart, BodyEnd - BodyStart);
2681   getParser().MacroMap[Name] = new Macro(Name, Body, Parameters);
2682   return false;
2683 }
2684
2685 /// ParseDirectiveEndMacro
2686 /// ::= .endm
2687 /// ::= .endmacro
2688 bool GenericAsmParser::ParseDirectiveEndMacro(StringRef Directive,
2689                                            SMLoc DirectiveLoc) {
2690   if (getLexer().isNot(AsmToken::EndOfStatement))
2691     return TokError("unexpected token in '" + Directive + "' directive");
2692
2693   // If we are inside a macro instantiation, terminate the current
2694   // instantiation.
2695   if (!getParser().ActiveMacros.empty()) {
2696     getParser().HandleMacroExit();
2697     return false;
2698   }
2699
2700   // Otherwise, this .endmacro is a stray entry in the file; well formed
2701   // .endmacro directives are handled during the macro definition parsing.
2702   return TokError("unexpected '" + Directive + "' in file, "
2703                   "no current macro definition");
2704 }
2705
2706 bool GenericAsmParser::ParseDirectiveLEB128(StringRef DirName, SMLoc) {
2707   getParser().CheckForValidSection();
2708
2709   const MCExpr *Value;
2710
2711   if (getParser().ParseExpression(Value))
2712     return true;
2713
2714   if (getLexer().isNot(AsmToken::EndOfStatement))
2715     return TokError("unexpected token in directive");
2716
2717   if (DirName[1] == 's')
2718     getStreamer().EmitSLEB128Value(Value);
2719   else
2720     getStreamer().EmitULEB128Value(Value);
2721
2722   return false;
2723 }
2724
2725
2726 /// \brief Create an MCAsmParser instance.
2727 MCAsmParser *llvm::createMCAsmParser(const Target &T, SourceMgr &SM,
2728                                      MCContext &C, MCStreamer &Out,
2729                                      const MCAsmInfo &MAI) {
2730   return new AsmParser(T, SM, C, Out, MAI);
2731 }