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      1 //===- DarwinAsmParser.cpp - Darwin (Mach-O) Assembly Parser --------------===//
      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 #include "llvm/MC/MCParser/MCAsmParserExtension.h"
     11 #include "llvm/ADT/StringRef.h"
     12 #include "llvm/ADT/StringSwitch.h"
     13 #include "llvm/ADT/Twine.h"
     14 #include "llvm/MC/MCContext.h"
     15 #include "llvm/MC/MCParser/MCAsmLexer.h"
     16 #include "llvm/MC/MCParser/MCAsmParser.h"
     17 #include "llvm/MC/MCSectionMachO.h"
     18 #include "llvm/MC/MCStreamer.h"
     19 #include "llvm/MC/MCSymbol.h"
     20 #include "llvm/Support/MemoryBuffer.h"
     21 #include "llvm/Support/SourceMgr.h"
     22 using namespace llvm;
     23 
     24 namespace {
     25 
     26 /// \brief Implementation of directive handling which is shared across all
     27 /// Darwin targets.
     28 class DarwinAsmParser : public MCAsmParserExtension {
     29   template<bool (DarwinAsmParser::*HandlerMethod)(StringRef, SMLoc)>
     30   void addDirectiveHandler(StringRef Directive) {
     31     MCAsmParser::ExtensionDirectiveHandler Handler = std::make_pair(
     32         this, HandleDirective<DarwinAsmParser, HandlerMethod>);
     33     getParser().addDirectiveHandler(Directive, Handler);
     34   }
     35 
     36   bool ParseSectionSwitch(const char *Segment, const char *Section,
     37                           unsigned TAA = 0, unsigned ImplicitAlign = 0,
     38                           unsigned StubSize = 0);
     39 
     40 public:
     41   DarwinAsmParser() {}
     42 
     43   virtual void Initialize(MCAsmParser &Parser) {
     44     // Call the base implementation.
     45     this->MCAsmParserExtension::Initialize(Parser);
     46 
     47     addDirectiveHandler<&DarwinAsmParser::ParseDirectiveDesc>(".desc");
     48     addDirectiveHandler<&DarwinAsmParser::ParseDirectiveLsym>(".lsym");
     49     addDirectiveHandler<&DarwinAsmParser::ParseDirectiveSubsectionsViaSymbols>(
     50       ".subsections_via_symbols");
     51     addDirectiveHandler<&DarwinAsmParser::ParseDirectiveDumpOrLoad>(".dump");
     52     addDirectiveHandler<&DarwinAsmParser::ParseDirectiveDumpOrLoad>(".load");
     53     addDirectiveHandler<&DarwinAsmParser::ParseDirectiveSection>(".section");
     54     addDirectiveHandler<&DarwinAsmParser::ParseDirectivePushSection>(
     55       ".pushsection");
     56     addDirectiveHandler<&DarwinAsmParser::ParseDirectivePopSection>(
     57       ".popsection");
     58     addDirectiveHandler<&DarwinAsmParser::ParseDirectivePrevious>(".previous");
     59     addDirectiveHandler<&DarwinAsmParser::ParseDirectiveSecureLogUnique>(
     60       ".secure_log_unique");
     61     addDirectiveHandler<&DarwinAsmParser::ParseDirectiveSecureLogReset>(
     62       ".secure_log_reset");
     63     addDirectiveHandler<&DarwinAsmParser::ParseDirectiveTBSS>(".tbss");
     64     addDirectiveHandler<&DarwinAsmParser::ParseDirectiveZerofill>(".zerofill");
     65 
     66     addDirectiveHandler<&DarwinAsmParser::ParseDirectiveDataRegion>(
     67       ".data_region");
     68     addDirectiveHandler<&DarwinAsmParser::ParseDirectiveDataRegionEnd>(
     69       ".end_data_region");
     70 
     71     // Special section directives.
     72     addDirectiveHandler<&DarwinAsmParser::ParseSectionDirectiveConst>(".const");
     73     addDirectiveHandler<&DarwinAsmParser::ParseSectionDirectiveConstData>(
     74       ".const_data");
     75     addDirectiveHandler<&DarwinAsmParser::ParseSectionDirectiveConstructor>(
     76       ".constructor");
     77     addDirectiveHandler<&DarwinAsmParser::ParseSectionDirectiveCString>(
     78       ".cstring");
     79     addDirectiveHandler<&DarwinAsmParser::ParseSectionDirectiveData>(".data");
     80     addDirectiveHandler<&DarwinAsmParser::ParseSectionDirectiveDestructor>(
     81       ".destructor");
     82     addDirectiveHandler<&DarwinAsmParser::ParseSectionDirectiveDyld>(".dyld");
     83     addDirectiveHandler<&DarwinAsmParser::ParseSectionDirectiveFVMLibInit0>(
     84       ".fvmlib_init0");
     85     addDirectiveHandler<&DarwinAsmParser::ParseSectionDirectiveFVMLibInit1>(
     86       ".fvmlib_init1");
     87     addDirectiveHandler<
     88       &DarwinAsmParser::ParseSectionDirectiveLazySymbolPointers>(
     89         ".lazy_symbol_pointer");
     90     addDirectiveHandler<&DarwinAsmParser::ParseDirectiveLinkerOption>(
     91       ".linker_option");
     92     addDirectiveHandler<&DarwinAsmParser::ParseSectionDirectiveLiteral16>(
     93       ".literal16");
     94     addDirectiveHandler<&DarwinAsmParser::ParseSectionDirectiveLiteral4>(
     95       ".literal4");
     96     addDirectiveHandler<&DarwinAsmParser::ParseSectionDirectiveLiteral8>(
     97       ".literal8");
     98     addDirectiveHandler<&DarwinAsmParser::ParseSectionDirectiveModInitFunc>(
     99       ".mod_init_func");
    100     addDirectiveHandler<&DarwinAsmParser::ParseSectionDirectiveModTermFunc>(
    101       ".mod_term_func");
    102     addDirectiveHandler<
    103       &DarwinAsmParser::ParseSectionDirectiveNonLazySymbolPointers>(
    104         ".non_lazy_symbol_pointer");
    105     addDirectiveHandler<&DarwinAsmParser::ParseSectionDirectiveObjCCatClsMeth>(
    106       ".objc_cat_cls_meth");
    107     addDirectiveHandler<&DarwinAsmParser::ParseSectionDirectiveObjCCatInstMeth>(
    108       ".objc_cat_inst_meth");
    109     addDirectiveHandler<&DarwinAsmParser::ParseSectionDirectiveObjCCategory>(
    110       ".objc_category");
    111     addDirectiveHandler<&DarwinAsmParser::ParseSectionDirectiveObjCClass>(
    112       ".objc_class");
    113     addDirectiveHandler<&DarwinAsmParser::ParseSectionDirectiveObjCClassNames>(
    114       ".objc_class_names");
    115     addDirectiveHandler<&DarwinAsmParser::ParseSectionDirectiveObjCClassVars>(
    116       ".objc_class_vars");
    117     addDirectiveHandler<&DarwinAsmParser::ParseSectionDirectiveObjCClsMeth>(
    118       ".objc_cls_meth");
    119     addDirectiveHandler<&DarwinAsmParser::ParseSectionDirectiveObjCClsRefs>(
    120       ".objc_cls_refs");
    121     addDirectiveHandler<&DarwinAsmParser::ParseSectionDirectiveObjCInstMeth>(
    122       ".objc_inst_meth");
    123     addDirectiveHandler<
    124       &DarwinAsmParser::ParseSectionDirectiveObjCInstanceVars>(
    125         ".objc_instance_vars");
    126     addDirectiveHandler<&DarwinAsmParser::ParseSectionDirectiveObjCMessageRefs>(
    127       ".objc_message_refs");
    128     addDirectiveHandler<&DarwinAsmParser::ParseSectionDirectiveObjCMetaClass>(
    129       ".objc_meta_class");
    130     addDirectiveHandler<
    131       &DarwinAsmParser::ParseSectionDirectiveObjCMethVarNames>(
    132         ".objc_meth_var_names");
    133     addDirectiveHandler<
    134       &DarwinAsmParser::ParseSectionDirectiveObjCMethVarTypes>(
    135         ".objc_meth_var_types");
    136     addDirectiveHandler<&DarwinAsmParser::ParseSectionDirectiveObjCModuleInfo>(
    137       ".objc_module_info");
    138     addDirectiveHandler<&DarwinAsmParser::ParseSectionDirectiveObjCProtocol>(
    139       ".objc_protocol");
    140     addDirectiveHandler<
    141       &DarwinAsmParser::ParseSectionDirectiveObjCSelectorStrs>(
    142         ".objc_selector_strs");
    143     addDirectiveHandler<
    144       &DarwinAsmParser::ParseSectionDirectiveObjCStringObject>(
    145         ".objc_string_object");
    146     addDirectiveHandler<&DarwinAsmParser::ParseSectionDirectiveObjCSymbols>(
    147       ".objc_symbols");
    148     addDirectiveHandler<&DarwinAsmParser::ParseSectionDirectivePICSymbolStub>(
    149       ".picsymbol_stub");
    150     addDirectiveHandler<&DarwinAsmParser::ParseSectionDirectiveStaticConst>(
    151       ".static_const");
    152     addDirectiveHandler<&DarwinAsmParser::ParseSectionDirectiveStaticData>(
    153       ".static_data");
    154     addDirectiveHandler<&DarwinAsmParser::ParseSectionDirectiveSymbolStub>(
    155       ".symbol_stub");
    156     addDirectiveHandler<&DarwinAsmParser::ParseSectionDirectiveTData>(".tdata");
    157     addDirectiveHandler<&DarwinAsmParser::ParseSectionDirectiveText>(".text");
    158     addDirectiveHandler<&DarwinAsmParser::ParseSectionDirectiveThreadInitFunc>(
    159       ".thread_init_func");
    160     addDirectiveHandler<&DarwinAsmParser::ParseSectionDirectiveTLV>(".tlv");
    161 
    162     addDirectiveHandler<&DarwinAsmParser::ParseSectionDirectiveIdent>(".ident");
    163   }
    164 
    165   bool ParseDirectiveDesc(StringRef, SMLoc);
    166   bool ParseDirectiveDumpOrLoad(StringRef, SMLoc);
    167   bool ParseDirectiveLsym(StringRef, SMLoc);
    168   bool ParseDirectiveLinkerOption(StringRef, SMLoc);
    169   bool ParseDirectiveSection(StringRef, SMLoc);
    170   bool ParseDirectivePushSection(StringRef, SMLoc);
    171   bool ParseDirectivePopSection(StringRef, SMLoc);
    172   bool ParseDirectivePrevious(StringRef, SMLoc);
    173   bool ParseDirectiveSecureLogReset(StringRef, SMLoc);
    174   bool ParseDirectiveSecureLogUnique(StringRef, SMLoc);
    175   bool ParseDirectiveSubsectionsViaSymbols(StringRef, SMLoc);
    176   bool ParseDirectiveTBSS(StringRef, SMLoc);
    177   bool ParseDirectiveZerofill(StringRef, SMLoc);
    178   bool ParseDirectiveDataRegion(StringRef, SMLoc);
    179   bool ParseDirectiveDataRegionEnd(StringRef, SMLoc);
    180 
    181   // Named Section Directive
    182   bool ParseSectionDirectiveConst(StringRef, SMLoc) {
    183     return ParseSectionSwitch("__TEXT", "__const");
    184   }
    185   bool ParseSectionDirectiveStaticConst(StringRef, SMLoc) {
    186     return ParseSectionSwitch("__TEXT", "__static_const");
    187   }
    188   bool ParseSectionDirectiveCString(StringRef, SMLoc) {
    189     return ParseSectionSwitch("__TEXT","__cstring",
    190                               MCSectionMachO::S_CSTRING_LITERALS);
    191   }
    192   bool ParseSectionDirectiveLiteral4(StringRef, SMLoc) {
    193     return ParseSectionSwitch("__TEXT", "__literal4",
    194                               MCSectionMachO::S_4BYTE_LITERALS, 4);
    195   }
    196   bool ParseSectionDirectiveLiteral8(StringRef, SMLoc) {
    197     return ParseSectionSwitch("__TEXT", "__literal8",
    198                               MCSectionMachO::S_8BYTE_LITERALS, 8);
    199   }
    200   bool ParseSectionDirectiveLiteral16(StringRef, SMLoc) {
    201     return ParseSectionSwitch("__TEXT","__literal16",
    202                               MCSectionMachO::S_16BYTE_LITERALS, 16);
    203   }
    204   bool ParseSectionDirectiveConstructor(StringRef, SMLoc) {
    205     return ParseSectionSwitch("__TEXT","__constructor");
    206   }
    207   bool ParseSectionDirectiveDestructor(StringRef, SMLoc) {
    208     return ParseSectionSwitch("__TEXT","__destructor");
    209   }
    210   bool ParseSectionDirectiveFVMLibInit0(StringRef, SMLoc) {
    211     return ParseSectionSwitch("__TEXT","__fvmlib_init0");
    212   }
    213   bool ParseSectionDirectiveFVMLibInit1(StringRef, SMLoc) {
    214     return ParseSectionSwitch("__TEXT","__fvmlib_init1");
    215   }
    216   bool ParseSectionDirectiveSymbolStub(StringRef, SMLoc) {
    217     return ParseSectionSwitch("__TEXT","__symbol_stub",
    218                               MCSectionMachO::S_SYMBOL_STUBS |
    219                               MCSectionMachO::S_ATTR_PURE_INSTRUCTIONS,
    220                               // FIXME: Different on PPC and ARM.
    221                               0, 16);
    222   }
    223   bool ParseSectionDirectivePICSymbolStub(StringRef, SMLoc) {
    224     return ParseSectionSwitch("__TEXT","__picsymbol_stub",
    225                               MCSectionMachO::S_SYMBOL_STUBS |
    226                               MCSectionMachO::S_ATTR_PURE_INSTRUCTIONS, 0, 26);
    227   }
    228   bool ParseSectionDirectiveData(StringRef, SMLoc) {
    229     return ParseSectionSwitch("__DATA", "__data");
    230   }
    231   bool ParseSectionDirectiveStaticData(StringRef, SMLoc) {
    232     return ParseSectionSwitch("__DATA", "__static_data");
    233   }
    234   bool ParseSectionDirectiveNonLazySymbolPointers(StringRef, SMLoc) {
    235     return ParseSectionSwitch("__DATA", "__nl_symbol_ptr",
    236                               MCSectionMachO::S_NON_LAZY_SYMBOL_POINTERS, 4);
    237   }
    238   bool ParseSectionDirectiveLazySymbolPointers(StringRef, SMLoc) {
    239     return ParseSectionSwitch("__DATA", "__la_symbol_ptr",
    240                               MCSectionMachO::S_LAZY_SYMBOL_POINTERS, 4);
    241   }
    242   bool ParseSectionDirectiveDyld(StringRef, SMLoc) {
    243     return ParseSectionSwitch("__DATA", "__dyld");
    244   }
    245   bool ParseSectionDirectiveModInitFunc(StringRef, SMLoc) {
    246     return ParseSectionSwitch("__DATA", "__mod_init_func",
    247                               MCSectionMachO::S_MOD_INIT_FUNC_POINTERS, 4);
    248   }
    249   bool ParseSectionDirectiveModTermFunc(StringRef, SMLoc) {
    250     return ParseSectionSwitch("__DATA", "__mod_term_func",
    251                               MCSectionMachO::S_MOD_TERM_FUNC_POINTERS, 4);
    252   }
    253   bool ParseSectionDirectiveConstData(StringRef, SMLoc) {
    254     return ParseSectionSwitch("__DATA", "__const");
    255   }
    256   bool ParseSectionDirectiveObjCClass(StringRef, SMLoc) {
    257     return ParseSectionSwitch("__OBJC", "__class",
    258                               MCSectionMachO::S_ATTR_NO_DEAD_STRIP);
    259   }
    260   bool ParseSectionDirectiveObjCMetaClass(StringRef, SMLoc) {
    261     return ParseSectionSwitch("__OBJC", "__meta_class",
    262                               MCSectionMachO::S_ATTR_NO_DEAD_STRIP);
    263   }
    264   bool ParseSectionDirectiveObjCCatClsMeth(StringRef, SMLoc) {
    265     return ParseSectionSwitch("__OBJC", "__cat_cls_meth",
    266                               MCSectionMachO::S_ATTR_NO_DEAD_STRIP);
    267   }
    268   bool ParseSectionDirectiveObjCCatInstMeth(StringRef, SMLoc) {
    269     return ParseSectionSwitch("__OBJC", "__cat_inst_meth",
    270                               MCSectionMachO::S_ATTR_NO_DEAD_STRIP);
    271   }
    272   bool ParseSectionDirectiveObjCProtocol(StringRef, SMLoc) {
    273     return ParseSectionSwitch("__OBJC", "__protocol",
    274                               MCSectionMachO::S_ATTR_NO_DEAD_STRIP);
    275   }
    276   bool ParseSectionDirectiveObjCStringObject(StringRef, SMLoc) {
    277     return ParseSectionSwitch("__OBJC", "__string_object",
    278                               MCSectionMachO::S_ATTR_NO_DEAD_STRIP);
    279   }
    280   bool ParseSectionDirectiveObjCClsMeth(StringRef, SMLoc) {
    281     return ParseSectionSwitch("__OBJC", "__cls_meth",
    282                               MCSectionMachO::S_ATTR_NO_DEAD_STRIP);
    283   }
    284   bool ParseSectionDirectiveObjCInstMeth(StringRef, SMLoc) {
    285     return ParseSectionSwitch("__OBJC", "__inst_meth",
    286                               MCSectionMachO::S_ATTR_NO_DEAD_STRIP);
    287   }
    288   bool ParseSectionDirectiveObjCClsRefs(StringRef, SMLoc) {
    289     return ParseSectionSwitch("__OBJC", "__cls_refs",
    290                               MCSectionMachO::S_ATTR_NO_DEAD_STRIP |
    291                               MCSectionMachO::S_LITERAL_POINTERS, 4);
    292   }
    293   bool ParseSectionDirectiveObjCMessageRefs(StringRef, SMLoc) {
    294     return ParseSectionSwitch("__OBJC", "__message_refs",
    295                               MCSectionMachO::S_ATTR_NO_DEAD_STRIP |
    296                               MCSectionMachO::S_LITERAL_POINTERS, 4);
    297   }
    298   bool ParseSectionDirectiveObjCSymbols(StringRef, SMLoc) {
    299     return ParseSectionSwitch("__OBJC", "__symbols",
    300                               MCSectionMachO::S_ATTR_NO_DEAD_STRIP);
    301   }
    302   bool ParseSectionDirectiveObjCCategory(StringRef, SMLoc) {
    303     return ParseSectionSwitch("__OBJC", "__category",
    304                               MCSectionMachO::S_ATTR_NO_DEAD_STRIP);
    305   }
    306   bool ParseSectionDirectiveObjCClassVars(StringRef, SMLoc) {
    307     return ParseSectionSwitch("__OBJC", "__class_vars",
    308                               MCSectionMachO::S_ATTR_NO_DEAD_STRIP);
    309   }
    310   bool ParseSectionDirectiveObjCInstanceVars(StringRef, SMLoc) {
    311     return ParseSectionSwitch("__OBJC", "__instance_vars",
    312                               MCSectionMachO::S_ATTR_NO_DEAD_STRIP);
    313   }
    314   bool ParseSectionDirectiveObjCModuleInfo(StringRef, SMLoc) {
    315     return ParseSectionSwitch("__OBJC", "__module_info",
    316                               MCSectionMachO::S_ATTR_NO_DEAD_STRIP);
    317   }
    318   bool ParseSectionDirectiveObjCClassNames(StringRef, SMLoc) {
    319     return ParseSectionSwitch("__TEXT", "__cstring",
    320                               MCSectionMachO::S_CSTRING_LITERALS);
    321   }
    322   bool ParseSectionDirectiveObjCMethVarTypes(StringRef, SMLoc) {
    323     return ParseSectionSwitch("__TEXT", "__cstring",
    324                               MCSectionMachO::S_CSTRING_LITERALS);
    325   }
    326   bool ParseSectionDirectiveObjCMethVarNames(StringRef, SMLoc) {
    327     return ParseSectionSwitch("__TEXT", "__cstring",
    328                               MCSectionMachO::S_CSTRING_LITERALS);
    329   }
    330   bool ParseSectionDirectiveObjCSelectorStrs(StringRef, SMLoc) {
    331     return ParseSectionSwitch("__OBJC", "__selector_strs",
    332                               MCSectionMachO::S_CSTRING_LITERALS);
    333   }
    334   bool ParseSectionDirectiveTData(StringRef, SMLoc) {
    335     return ParseSectionSwitch("__DATA", "__thread_data",
    336                               MCSectionMachO::S_THREAD_LOCAL_REGULAR);
    337   }
    338   bool ParseSectionDirectiveText(StringRef, SMLoc) {
    339     return ParseSectionSwitch("__TEXT", "__text",
    340                               MCSectionMachO::S_ATTR_PURE_INSTRUCTIONS);
    341   }
    342   bool ParseSectionDirectiveTLV(StringRef, SMLoc) {
    343     return ParseSectionSwitch("__DATA", "__thread_vars",
    344                               MCSectionMachO::S_THREAD_LOCAL_VARIABLES);
    345   }
    346   bool ParseSectionDirectiveIdent(StringRef, SMLoc) {
    347     // Darwin silently ignores the .ident directive.
    348     getParser().eatToEndOfStatement();
    349     return false;
    350   }
    351   bool ParseSectionDirectiveThreadInitFunc(StringRef, SMLoc) {
    352     return ParseSectionSwitch("__DATA", "__thread_init",
    353                          MCSectionMachO::S_THREAD_LOCAL_INIT_FUNCTION_POINTERS);
    354   }
    355 
    356 };
    357 
    358 } // end anonymous namespace
    359 
    360 bool DarwinAsmParser::ParseSectionSwitch(const char *Segment,
    361                                          const char *Section,
    362                                          unsigned TAA, unsigned Align,
    363                                          unsigned StubSize) {
    364   if (getLexer().isNot(AsmToken::EndOfStatement))
    365     return TokError("unexpected token in section switching directive");
    366   Lex();
    367 
    368   // FIXME: Arch specific.
    369   bool isText = TAA & MCSectionMachO::S_ATTR_PURE_INSTRUCTIONS;
    370   getStreamer().SwitchSection(getContext().getMachOSection(
    371                                 Segment, Section, TAA, StubSize,
    372                                 isText ? SectionKind::getText()
    373                                        : SectionKind::getDataRel()));
    374 
    375   // Set the implicit alignment, if any.
    376   //
    377   // FIXME: This isn't really what 'as' does; I think it just uses the implicit
    378   // alignment on the section (e.g., if one manually inserts bytes into the
    379   // section, then just issuing the section switch directive will not realign
    380   // the section. However, this is arguably more reasonable behavior, and there
    381   // is no good reason for someone to intentionally emit incorrectly sized
    382   // values into the implicitly aligned sections.
    383   if (Align)
    384     getStreamer().EmitValueToAlignment(Align, 0, 1, 0);
    385 
    386   return false;
    387 }
    388 
    389 /// ParseDirectiveDesc
    390 ///  ::= .desc identifier , expression
    391 bool DarwinAsmParser::ParseDirectiveDesc(StringRef, SMLoc) {
    392   StringRef Name;
    393   if (getParser().parseIdentifier(Name))
    394     return TokError("expected identifier in directive");
    395 
    396   // Handle the identifier as the key symbol.
    397   MCSymbol *Sym = getContext().GetOrCreateSymbol(Name);
    398 
    399   if (getLexer().isNot(AsmToken::Comma))
    400     return TokError("unexpected token in '.desc' directive");
    401   Lex();
    402 
    403   int64_t DescValue;
    404   if (getParser().parseAbsoluteExpression(DescValue))
    405     return true;
    406 
    407   if (getLexer().isNot(AsmToken::EndOfStatement))
    408     return TokError("unexpected token in '.desc' directive");
    409 
    410   Lex();
    411 
    412   // Set the n_desc field of this Symbol to this DescValue
    413   getStreamer().EmitSymbolDesc(Sym, DescValue);
    414 
    415   return false;
    416 }
    417 
    418 /// ParseDirectiveDumpOrLoad
    419 ///  ::= ( .dump | .load ) "filename"
    420 bool DarwinAsmParser::ParseDirectiveDumpOrLoad(StringRef Directive,
    421                                                SMLoc IDLoc) {
    422   bool IsDump = Directive == ".dump";
    423   if (getLexer().isNot(AsmToken::String))
    424     return TokError("expected string in '.dump' or '.load' directive");
    425 
    426   Lex();
    427 
    428   if (getLexer().isNot(AsmToken::EndOfStatement))
    429     return TokError("unexpected token in '.dump' or '.load' directive");
    430 
    431   Lex();
    432 
    433   // FIXME: If/when .dump and .load are implemented they will be done in the
    434   // the assembly parser and not have any need for an MCStreamer API.
    435   if (IsDump)
    436     return Warning(IDLoc, "ignoring directive .dump for now");
    437   else
    438     return Warning(IDLoc, "ignoring directive .load for now");
    439 }
    440 
    441 /// ParseDirectiveLinkerOption
    442 ///  ::= .linker_option "string" ( , "string" )*
    443 bool DarwinAsmParser::ParseDirectiveLinkerOption(StringRef IDVal, SMLoc) {
    444   SmallVector<std::string, 4> Args;
    445   for (;;) {
    446     if (getLexer().isNot(AsmToken::String))
    447       return TokError("expected string in '" + Twine(IDVal) + "' directive");
    448 
    449     std::string Data;
    450     if (getParser().parseEscapedString(Data))
    451       return true;
    452 
    453     Args.push_back(Data);
    454 
    455     Lex();
    456     if (getLexer().is(AsmToken::EndOfStatement))
    457       break;
    458 
    459     if (getLexer().isNot(AsmToken::Comma))
    460       return TokError("unexpected token in '" + Twine(IDVal) + "' directive");
    461     Lex();
    462   }
    463 
    464   getStreamer().EmitLinkerOptions(Args);
    465   return false;
    466 }
    467 
    468 /// ParseDirectiveLsym
    469 ///  ::= .lsym identifier , expression
    470 bool DarwinAsmParser::ParseDirectiveLsym(StringRef, SMLoc) {
    471   StringRef Name;
    472   if (getParser().parseIdentifier(Name))
    473     return TokError("expected identifier in directive");
    474 
    475   // Handle the identifier as the key symbol.
    476   MCSymbol *Sym = getContext().GetOrCreateSymbol(Name);
    477 
    478   if (getLexer().isNot(AsmToken::Comma))
    479     return TokError("unexpected token in '.lsym' directive");
    480   Lex();
    481 
    482   const MCExpr *Value;
    483   if (getParser().parseExpression(Value))
    484     return true;
    485 
    486   if (getLexer().isNot(AsmToken::EndOfStatement))
    487     return TokError("unexpected token in '.lsym' directive");
    488 
    489   Lex();
    490 
    491   // We don't currently support this directive.
    492   //
    493   // FIXME: Diagnostic location!
    494   (void) Sym;
    495   return TokError("directive '.lsym' is unsupported");
    496 }
    497 
    498 /// ParseDirectiveSection:
    499 ///   ::= .section identifier (',' identifier)*
    500 bool DarwinAsmParser::ParseDirectiveSection(StringRef, SMLoc) {
    501   SMLoc Loc = getLexer().getLoc();
    502 
    503   StringRef SectionName;
    504   if (getParser().parseIdentifier(SectionName))
    505     return Error(Loc, "expected identifier after '.section' directive");
    506 
    507   // Verify there is a following comma.
    508   if (!getLexer().is(AsmToken::Comma))
    509     return TokError("unexpected token in '.section' directive");
    510 
    511   std::string SectionSpec = SectionName;
    512   SectionSpec += ",";
    513 
    514   // Add all the tokens until the end of the line, ParseSectionSpecifier will
    515   // handle this.
    516   StringRef EOL = getLexer().LexUntilEndOfStatement();
    517   SectionSpec.append(EOL.begin(), EOL.end());
    518 
    519   Lex();
    520   if (getLexer().isNot(AsmToken::EndOfStatement))
    521     return TokError("unexpected token in '.section' directive");
    522   Lex();
    523 
    524 
    525   StringRef Segment, Section;
    526   unsigned StubSize;
    527   unsigned TAA;
    528   bool TAAParsed;
    529   std::string ErrorStr =
    530     MCSectionMachO::ParseSectionSpecifier(SectionSpec, Segment, Section,
    531                                           TAA, TAAParsed, StubSize);
    532 
    533   if (!ErrorStr.empty())
    534     return Error(Loc, ErrorStr.c_str());
    535 
    536   // FIXME: Arch specific.
    537   bool isText = Segment == "__TEXT";  // FIXME: Hack.
    538   getStreamer().SwitchSection(getContext().getMachOSection(
    539                                 Segment, Section, TAA, StubSize,
    540                                 isText ? SectionKind::getText()
    541                                 : SectionKind::getDataRel()));
    542   return false;
    543 }
    544 
    545 /// ParseDirectivePushSection:
    546 ///   ::= .pushsection identifier (',' identifier)*
    547 bool DarwinAsmParser::ParseDirectivePushSection(StringRef S, SMLoc Loc) {
    548   getStreamer().PushSection();
    549 
    550   if (ParseDirectiveSection(S, Loc)) {
    551     getStreamer().PopSection();
    552     return true;
    553   }
    554 
    555   return false;
    556 }
    557 
    558 /// ParseDirectivePopSection:
    559 ///   ::= .popsection
    560 bool DarwinAsmParser::ParseDirectivePopSection(StringRef, SMLoc) {
    561   if (!getStreamer().PopSection())
    562     return TokError(".popsection without corresponding .pushsection");
    563   return false;
    564 }
    565 
    566 /// ParseDirectivePrevious:
    567 ///   ::= .previous
    568 bool DarwinAsmParser::ParseDirectivePrevious(StringRef DirName, SMLoc) {
    569   const MCSection *PreviousSection = getStreamer().getPreviousSection();
    570   if (PreviousSection == NULL)
    571       return TokError(".previous without corresponding .section");
    572   getStreamer().SwitchSection(PreviousSection);
    573   return false;
    574 }
    575 
    576 /// ParseDirectiveSecureLogUnique
    577 ///  ::= .secure_log_unique ... message ...
    578 bool DarwinAsmParser::ParseDirectiveSecureLogUnique(StringRef, SMLoc IDLoc) {
    579   StringRef LogMessage = getParser().parseStringToEndOfStatement();
    580   if (getLexer().isNot(AsmToken::EndOfStatement))
    581     return TokError("unexpected token in '.secure_log_unique' directive");
    582 
    583   if (getContext().getSecureLogUsed() != false)
    584     return Error(IDLoc, ".secure_log_unique specified multiple times");
    585 
    586   // Get the secure log path.
    587   const char *SecureLogFile = getContext().getSecureLogFile();
    588   if (SecureLogFile == NULL)
    589     return Error(IDLoc, ".secure_log_unique used but AS_SECURE_LOG_FILE "
    590                  "environment variable unset.");
    591 
    592   // Open the secure log file if we haven't already.
    593   raw_ostream *OS = getContext().getSecureLog();
    594   if (OS == NULL) {
    595     std::string Err;
    596     OS = new raw_fd_ostream(SecureLogFile, Err, raw_fd_ostream::F_Append);
    597     if (!Err.empty()) {
    598        delete OS;
    599        return Error(IDLoc, Twine("can't open secure log file: ") +
    600                     SecureLogFile + " (" + Err + ")");
    601     }
    602     getContext().setSecureLog(OS);
    603   }
    604 
    605   // Write the message.
    606   int CurBuf = getSourceManager().FindBufferContainingLoc(IDLoc);
    607   *OS << getSourceManager().getBufferInfo(CurBuf).Buffer->getBufferIdentifier()
    608       << ":" << getSourceManager().FindLineNumber(IDLoc, CurBuf) << ":"
    609       << LogMessage + "\n";
    610 
    611   getContext().setSecureLogUsed(true);
    612 
    613   return false;
    614 }
    615 
    616 /// ParseDirectiveSecureLogReset
    617 ///  ::= .secure_log_reset
    618 bool DarwinAsmParser::ParseDirectiveSecureLogReset(StringRef, SMLoc IDLoc) {
    619   if (getLexer().isNot(AsmToken::EndOfStatement))
    620     return TokError("unexpected token in '.secure_log_reset' directive");
    621 
    622   Lex();
    623 
    624   getContext().setSecureLogUsed(false);
    625 
    626   return false;
    627 }
    628 
    629 /// ParseDirectiveSubsectionsViaSymbols
    630 ///  ::= .subsections_via_symbols
    631 bool DarwinAsmParser::ParseDirectiveSubsectionsViaSymbols(StringRef, SMLoc) {
    632   if (getLexer().isNot(AsmToken::EndOfStatement))
    633     return TokError("unexpected token in '.subsections_via_symbols' directive");
    634 
    635   Lex();
    636 
    637   getStreamer().EmitAssemblerFlag(MCAF_SubsectionsViaSymbols);
    638 
    639   return false;
    640 }
    641 
    642 /// ParseDirectiveTBSS
    643 ///  ::= .tbss identifier, size, align
    644 bool DarwinAsmParser::ParseDirectiveTBSS(StringRef, SMLoc) {
    645   SMLoc IDLoc = getLexer().getLoc();
    646   StringRef Name;
    647   if (getParser().parseIdentifier(Name))
    648     return TokError("expected identifier in directive");
    649 
    650   // Handle the identifier as the key symbol.
    651   MCSymbol *Sym = getContext().GetOrCreateSymbol(Name);
    652 
    653   if (getLexer().isNot(AsmToken::Comma))
    654     return TokError("unexpected token in directive");
    655   Lex();
    656 
    657   int64_t Size;
    658   SMLoc SizeLoc = getLexer().getLoc();
    659   if (getParser().parseAbsoluteExpression(Size))
    660     return true;
    661 
    662   int64_t Pow2Alignment = 0;
    663   SMLoc Pow2AlignmentLoc;
    664   if (getLexer().is(AsmToken::Comma)) {
    665     Lex();
    666     Pow2AlignmentLoc = getLexer().getLoc();
    667     if (getParser().parseAbsoluteExpression(Pow2Alignment))
    668       return true;
    669   }
    670 
    671   if (getLexer().isNot(AsmToken::EndOfStatement))
    672     return TokError("unexpected token in '.tbss' directive");
    673 
    674   Lex();
    675 
    676   if (Size < 0)
    677     return Error(SizeLoc, "invalid '.tbss' directive size, can't be less than"
    678                  "zero");
    679 
    680   // FIXME: Diagnose overflow.
    681   if (Pow2Alignment < 0)
    682     return Error(Pow2AlignmentLoc, "invalid '.tbss' alignment, can't be less"
    683                  "than zero");
    684 
    685   if (!Sym->isUndefined())
    686     return Error(IDLoc, "invalid symbol redefinition");
    687 
    688   getStreamer().EmitTBSSSymbol(getContext().getMachOSection(
    689                                  "__DATA", "__thread_bss",
    690                                  MCSectionMachO::S_THREAD_LOCAL_ZEROFILL,
    691                                  0, SectionKind::getThreadBSS()),
    692                                Sym, Size, 1 << Pow2Alignment);
    693 
    694   return false;
    695 }
    696 
    697 /// ParseDirectiveZerofill
    698 ///  ::= .zerofill segname , sectname [, identifier , size_expression [
    699 ///      , align_expression ]]
    700 bool DarwinAsmParser::ParseDirectiveZerofill(StringRef, SMLoc) {
    701   StringRef Segment;
    702   if (getParser().parseIdentifier(Segment))
    703     return TokError("expected segment name after '.zerofill' directive");
    704 
    705   if (getLexer().isNot(AsmToken::Comma))
    706     return TokError("unexpected token in directive");
    707   Lex();
    708 
    709   StringRef Section;
    710   if (getParser().parseIdentifier(Section))
    711     return TokError("expected section name after comma in '.zerofill' "
    712                     "directive");
    713 
    714   // If this is the end of the line all that was wanted was to create the
    715   // the section but with no symbol.
    716   if (getLexer().is(AsmToken::EndOfStatement)) {
    717     // Create the zerofill section but no symbol
    718     getStreamer().EmitZerofill(getContext().getMachOSection(
    719                                  Segment, Section, MCSectionMachO::S_ZEROFILL,
    720                                  0, SectionKind::getBSS()));
    721     return false;
    722   }
    723 
    724   if (getLexer().isNot(AsmToken::Comma))
    725     return TokError("unexpected token in directive");
    726   Lex();
    727 
    728   SMLoc IDLoc = getLexer().getLoc();
    729   StringRef IDStr;
    730   if (getParser().parseIdentifier(IDStr))
    731     return TokError("expected identifier in directive");
    732 
    733   // handle the identifier as the key symbol.
    734   MCSymbol *Sym = getContext().GetOrCreateSymbol(IDStr);
    735 
    736   if (getLexer().isNot(AsmToken::Comma))
    737     return TokError("unexpected token in directive");
    738   Lex();
    739 
    740   int64_t Size;
    741   SMLoc SizeLoc = getLexer().getLoc();
    742   if (getParser().parseAbsoluteExpression(Size))
    743     return true;
    744 
    745   int64_t Pow2Alignment = 0;
    746   SMLoc Pow2AlignmentLoc;
    747   if (getLexer().is(AsmToken::Comma)) {
    748     Lex();
    749     Pow2AlignmentLoc = getLexer().getLoc();
    750     if (getParser().parseAbsoluteExpression(Pow2Alignment))
    751       return true;
    752   }
    753 
    754   if (getLexer().isNot(AsmToken::EndOfStatement))
    755     return TokError("unexpected token in '.zerofill' directive");
    756 
    757   Lex();
    758 
    759   if (Size < 0)
    760     return Error(SizeLoc, "invalid '.zerofill' directive size, can't be less "
    761                  "than zero");
    762 
    763   // NOTE: The alignment in the directive is a power of 2 value, the assembler
    764   // may internally end up wanting an alignment in bytes.
    765   // FIXME: Diagnose overflow.
    766   if (Pow2Alignment < 0)
    767     return Error(Pow2AlignmentLoc, "invalid '.zerofill' directive alignment, "
    768                  "can't be less than zero");
    769 
    770   if (!Sym->isUndefined())
    771     return Error(IDLoc, "invalid symbol redefinition");
    772 
    773   // Create the zerofill Symbol with Size and Pow2Alignment
    774   //
    775   // FIXME: Arch specific.
    776   getStreamer().EmitZerofill(getContext().getMachOSection(
    777                                Segment, Section, MCSectionMachO::S_ZEROFILL,
    778                                0, SectionKind::getBSS()),
    779                              Sym, Size, 1 << Pow2Alignment);
    780 
    781   return false;
    782 }
    783 
    784 /// ParseDirectiveDataRegion
    785 ///  ::= .data_region [ ( jt8 | jt16 | jt32 ) ]
    786 bool DarwinAsmParser::ParseDirectiveDataRegion(StringRef, SMLoc) {
    787   if (getLexer().is(AsmToken::EndOfStatement)) {
    788     Lex();
    789     getStreamer().EmitDataRegion(MCDR_DataRegion);
    790     return false;
    791   }
    792   StringRef RegionType;
    793   SMLoc Loc = getParser().getTok().getLoc();
    794   if (getParser().parseIdentifier(RegionType))
    795     return TokError("expected region type after '.data_region' directive");
    796   int Kind = StringSwitch<int>(RegionType)
    797     .Case("jt8", MCDR_DataRegionJT8)
    798     .Case("jt16", MCDR_DataRegionJT16)
    799     .Case("jt32", MCDR_DataRegionJT32)
    800     .Default(-1);
    801   if (Kind == -1)
    802     return Error(Loc, "unknown region type in '.data_region' directive");
    803   Lex();
    804 
    805   getStreamer().EmitDataRegion((MCDataRegionType)Kind);
    806   return false;
    807 }
    808 
    809 /// ParseDirectiveDataRegionEnd
    810 ///  ::= .end_data_region
    811 bool DarwinAsmParser::ParseDirectiveDataRegionEnd(StringRef, SMLoc) {
    812   if (getLexer().isNot(AsmToken::EndOfStatement))
    813     return TokError("unexpected token in '.end_data_region' directive");
    814 
    815   Lex();
    816   getStreamer().EmitDataRegion(MCDR_DataRegionEnd);
    817   return false;
    818 }
    819 
    820 namespace llvm {
    821 
    822 MCAsmParserExtension *createDarwinAsmParser() {
    823   return new DarwinAsmParser;
    824 }
    825 
    826 } // end llvm namespace
    827