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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/STLExtras.h"
12 #include "llvm/ADT/StringRef.h"
13 #include "llvm/ADT/StringSwitch.h"
14 #include "llvm/ADT/Triple.h"
15 #include "llvm/ADT/Twine.h"
16 #include "llvm/MC/MCContext.h"
17 #include "llvm/MC/MCObjectFileInfo.h"
18 #include "llvm/MC/MCParser/MCAsmLexer.h"
19 #include "llvm/MC/MCParser/MCAsmParser.h"
20 #include "llvm/MC/MCSectionMachO.h"
21 #include "llvm/MC/MCStreamer.h"
22 #include "llvm/MC/MCSymbol.h"
23 #include "llvm/Support/FileSystem.h"
24 #include "llvm/Support/MemoryBuffer.h"
25 #include "llvm/Support/SourceMgr.h"
26 using namespace llvm;
27 
28 namespace {
29 
30 /// \brief Implementation of directive handling which is shared across all
31 /// Darwin targets.
32 class DarwinAsmParser : public MCAsmParserExtension {
33   template<bool (DarwinAsmParser::*HandlerMethod)(StringRef, SMLoc)>
addDirectiveHandler(StringRef Directive)34   void addDirectiveHandler(StringRef Directive) {
35     MCAsmParser::ExtensionDirectiveHandler Handler = std::make_pair(
36         this, HandleDirective<DarwinAsmParser, HandlerMethod>);
37     getParser().addDirectiveHandler(Directive, Handler);
38   }
39 
40   bool parseSectionSwitch(const char *Segment, const char *Section,
41                           unsigned TAA = 0, unsigned ImplicitAlign = 0,
42                           unsigned StubSize = 0);
43 
44   SMLoc LastVersionMinDirective;
45 
46 public:
DarwinAsmParser()47   DarwinAsmParser() {}
48 
Initialize(MCAsmParser & Parser)49   void Initialize(MCAsmParser &Parser) override {
50     // Call the base implementation.
51     this->MCAsmParserExtension::Initialize(Parser);
52 
53     addDirectiveHandler<&DarwinAsmParser::parseDirectiveAltEntry>(".alt_entry");
54     addDirectiveHandler<&DarwinAsmParser::parseDirectiveDesc>(".desc");
55     addDirectiveHandler<&DarwinAsmParser::parseDirectiveIndirectSymbol>(
56       ".indirect_symbol");
57     addDirectiveHandler<&DarwinAsmParser::parseDirectiveLsym>(".lsym");
58     addDirectiveHandler<&DarwinAsmParser::parseDirectiveSubsectionsViaSymbols>(
59       ".subsections_via_symbols");
60     addDirectiveHandler<&DarwinAsmParser::parseDirectiveDumpOrLoad>(".dump");
61     addDirectiveHandler<&DarwinAsmParser::parseDirectiveDumpOrLoad>(".load");
62     addDirectiveHandler<&DarwinAsmParser::parseDirectiveSection>(".section");
63     addDirectiveHandler<&DarwinAsmParser::parseDirectivePushSection>(
64       ".pushsection");
65     addDirectiveHandler<&DarwinAsmParser::parseDirectivePopSection>(
66       ".popsection");
67     addDirectiveHandler<&DarwinAsmParser::parseDirectivePrevious>(".previous");
68     addDirectiveHandler<&DarwinAsmParser::parseDirectiveSecureLogUnique>(
69       ".secure_log_unique");
70     addDirectiveHandler<&DarwinAsmParser::parseDirectiveSecureLogReset>(
71       ".secure_log_reset");
72     addDirectiveHandler<&DarwinAsmParser::parseDirectiveTBSS>(".tbss");
73     addDirectiveHandler<&DarwinAsmParser::parseDirectiveZerofill>(".zerofill");
74 
75     addDirectiveHandler<&DarwinAsmParser::parseDirectiveDataRegion>(
76       ".data_region");
77     addDirectiveHandler<&DarwinAsmParser::parseDirectiveDataRegionEnd>(
78       ".end_data_region");
79 
80     // Special section directives.
81     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveBss>(".bss");
82     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveConst>(".const");
83     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveConstData>(
84       ".const_data");
85     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveConstructor>(
86       ".constructor");
87     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveCString>(
88       ".cstring");
89     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveData>(".data");
90     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveDestructor>(
91       ".destructor");
92     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveDyld>(".dyld");
93     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveFVMLibInit0>(
94       ".fvmlib_init0");
95     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveFVMLibInit1>(
96       ".fvmlib_init1");
97     addDirectiveHandler<
98       &DarwinAsmParser::parseSectionDirectiveLazySymbolPointers>(
99         ".lazy_symbol_pointer");
100     addDirectiveHandler<&DarwinAsmParser::parseDirectiveLinkerOption>(
101       ".linker_option");
102     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveLiteral16>(
103       ".literal16");
104     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveLiteral4>(
105       ".literal4");
106     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveLiteral8>(
107       ".literal8");
108     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveModInitFunc>(
109       ".mod_init_func");
110     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveModTermFunc>(
111       ".mod_term_func");
112     addDirectiveHandler<
113       &DarwinAsmParser::parseSectionDirectiveNonLazySymbolPointers>(
114         ".non_lazy_symbol_pointer");
115     addDirectiveHandler<
116       &DarwinAsmParser::parseSectionDirectiveThreadLocalVariablePointers>(
117         ".thread_local_variable_pointer");
118     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveObjCCatClsMeth>(
119       ".objc_cat_cls_meth");
120     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveObjCCatInstMeth>(
121       ".objc_cat_inst_meth");
122     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveObjCCategory>(
123       ".objc_category");
124     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveObjCClass>(
125       ".objc_class");
126     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveObjCClassNames>(
127       ".objc_class_names");
128     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveObjCClassVars>(
129       ".objc_class_vars");
130     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveObjCClsMeth>(
131       ".objc_cls_meth");
132     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveObjCClsRefs>(
133       ".objc_cls_refs");
134     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveObjCInstMeth>(
135       ".objc_inst_meth");
136     addDirectiveHandler<
137       &DarwinAsmParser::parseSectionDirectiveObjCInstanceVars>(
138         ".objc_instance_vars");
139     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveObjCMessageRefs>(
140       ".objc_message_refs");
141     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveObjCMetaClass>(
142       ".objc_meta_class");
143     addDirectiveHandler<
144       &DarwinAsmParser::parseSectionDirectiveObjCMethVarNames>(
145         ".objc_meth_var_names");
146     addDirectiveHandler<
147       &DarwinAsmParser::parseSectionDirectiveObjCMethVarTypes>(
148         ".objc_meth_var_types");
149     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveObjCModuleInfo>(
150       ".objc_module_info");
151     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveObjCProtocol>(
152       ".objc_protocol");
153     addDirectiveHandler<
154       &DarwinAsmParser::parseSectionDirectiveObjCSelectorStrs>(
155         ".objc_selector_strs");
156     addDirectiveHandler<
157       &DarwinAsmParser::parseSectionDirectiveObjCStringObject>(
158         ".objc_string_object");
159     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveObjCSymbols>(
160       ".objc_symbols");
161     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectivePICSymbolStub>(
162       ".picsymbol_stub");
163     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveStaticConst>(
164       ".static_const");
165     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveStaticData>(
166       ".static_data");
167     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveSymbolStub>(
168       ".symbol_stub");
169     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveTData>(".tdata");
170     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveText>(".text");
171     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveThreadInitFunc>(
172       ".thread_init_func");
173     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveTLV>(".tlv");
174 
175     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveIdent>(".ident");
176     addDirectiveHandler<&DarwinAsmParser::parseVersionMin>(
177       ".watchos_version_min");
178     addDirectiveHandler<&DarwinAsmParser::parseVersionMin>(".tvos_version_min");
179     addDirectiveHandler<&DarwinAsmParser::parseVersionMin>(".ios_version_min");
180     addDirectiveHandler<&DarwinAsmParser::parseVersionMin>(
181       ".macosx_version_min");
182 
183     LastVersionMinDirective = SMLoc();
184   }
185 
186   bool parseDirectiveAltEntry(StringRef, SMLoc);
187   bool parseDirectiveDesc(StringRef, SMLoc);
188   bool parseDirectiveIndirectSymbol(StringRef, SMLoc);
189   bool parseDirectiveDumpOrLoad(StringRef, SMLoc);
190   bool parseDirectiveLsym(StringRef, SMLoc);
191   bool parseDirectiveLinkerOption(StringRef, SMLoc);
192   bool parseDirectiveSection(StringRef, SMLoc);
193   bool parseDirectivePushSection(StringRef, SMLoc);
194   bool parseDirectivePopSection(StringRef, SMLoc);
195   bool parseDirectivePrevious(StringRef, SMLoc);
196   bool parseDirectiveSecureLogReset(StringRef, SMLoc);
197   bool parseDirectiveSecureLogUnique(StringRef, SMLoc);
198   bool parseDirectiveSubsectionsViaSymbols(StringRef, SMLoc);
199   bool parseDirectiveTBSS(StringRef, SMLoc);
200   bool parseDirectiveZerofill(StringRef, SMLoc);
201   bool parseDirectiveDataRegion(StringRef, SMLoc);
202   bool parseDirectiveDataRegionEnd(StringRef, SMLoc);
203 
204   // Named Section Directive
parseSectionDirectiveBss(StringRef,SMLoc)205   bool parseSectionDirectiveBss(StringRef, SMLoc) {
206     return parseSectionSwitch("__DATA", "__bss");
207   }
208 
parseSectionDirectiveConst(StringRef,SMLoc)209   bool parseSectionDirectiveConst(StringRef, SMLoc) {
210     return parseSectionSwitch("__TEXT", "__const");
211   }
parseSectionDirectiveStaticConst(StringRef,SMLoc)212   bool parseSectionDirectiveStaticConst(StringRef, SMLoc) {
213     return parseSectionSwitch("__TEXT", "__static_const");
214   }
parseSectionDirectiveCString(StringRef,SMLoc)215   bool parseSectionDirectiveCString(StringRef, SMLoc) {
216     return parseSectionSwitch("__TEXT","__cstring",
217                               MachO::S_CSTRING_LITERALS);
218   }
parseSectionDirectiveLiteral4(StringRef,SMLoc)219   bool parseSectionDirectiveLiteral4(StringRef, SMLoc) {
220     return parseSectionSwitch("__TEXT", "__literal4",
221                               MachO::S_4BYTE_LITERALS, 4);
222   }
parseSectionDirectiveLiteral8(StringRef,SMLoc)223   bool parseSectionDirectiveLiteral8(StringRef, SMLoc) {
224     return parseSectionSwitch("__TEXT", "__literal8",
225                               MachO::S_8BYTE_LITERALS, 8);
226   }
parseSectionDirectiveLiteral16(StringRef,SMLoc)227   bool parseSectionDirectiveLiteral16(StringRef, SMLoc) {
228     return parseSectionSwitch("__TEXT","__literal16",
229                               MachO::S_16BYTE_LITERALS, 16);
230   }
parseSectionDirectiveConstructor(StringRef,SMLoc)231   bool parseSectionDirectiveConstructor(StringRef, SMLoc) {
232     return parseSectionSwitch("__TEXT","__constructor");
233   }
parseSectionDirectiveDestructor(StringRef,SMLoc)234   bool parseSectionDirectiveDestructor(StringRef, SMLoc) {
235     return parseSectionSwitch("__TEXT","__destructor");
236   }
parseSectionDirectiveFVMLibInit0(StringRef,SMLoc)237   bool parseSectionDirectiveFVMLibInit0(StringRef, SMLoc) {
238     return parseSectionSwitch("__TEXT","__fvmlib_init0");
239   }
parseSectionDirectiveFVMLibInit1(StringRef,SMLoc)240   bool parseSectionDirectiveFVMLibInit1(StringRef, SMLoc) {
241     return parseSectionSwitch("__TEXT","__fvmlib_init1");
242   }
parseSectionDirectiveSymbolStub(StringRef,SMLoc)243   bool parseSectionDirectiveSymbolStub(StringRef, SMLoc) {
244     return parseSectionSwitch("__TEXT","__symbol_stub",
245                               MachO::S_SYMBOL_STUBS |
246                               MachO::S_ATTR_PURE_INSTRUCTIONS,
247                               // FIXME: Different on PPC and ARM.
248                               0, 16);
249   }
parseSectionDirectivePICSymbolStub(StringRef,SMLoc)250   bool parseSectionDirectivePICSymbolStub(StringRef, SMLoc) {
251     return parseSectionSwitch("__TEXT","__picsymbol_stub",
252                               MachO::S_SYMBOL_STUBS |
253                               MachO::S_ATTR_PURE_INSTRUCTIONS, 0, 26);
254   }
parseSectionDirectiveData(StringRef,SMLoc)255   bool parseSectionDirectiveData(StringRef, SMLoc) {
256     return parseSectionSwitch("__DATA", "__data");
257   }
parseSectionDirectiveStaticData(StringRef,SMLoc)258   bool parseSectionDirectiveStaticData(StringRef, SMLoc) {
259     return parseSectionSwitch("__DATA", "__static_data");
260   }
parseSectionDirectiveNonLazySymbolPointers(StringRef,SMLoc)261   bool parseSectionDirectiveNonLazySymbolPointers(StringRef, SMLoc) {
262     return parseSectionSwitch("__DATA", "__nl_symbol_ptr",
263                               MachO::S_NON_LAZY_SYMBOL_POINTERS, 4);
264   }
parseSectionDirectiveLazySymbolPointers(StringRef,SMLoc)265   bool parseSectionDirectiveLazySymbolPointers(StringRef, SMLoc) {
266     return parseSectionSwitch("__DATA", "__la_symbol_ptr",
267                               MachO::S_LAZY_SYMBOL_POINTERS, 4);
268   }
parseSectionDirectiveThreadLocalVariablePointers(StringRef,SMLoc)269   bool parseSectionDirectiveThreadLocalVariablePointers(StringRef, SMLoc) {
270     return parseSectionSwitch("__DATA", "__thread_ptr",
271                               MachO::S_THREAD_LOCAL_VARIABLE_POINTERS, 4);
272   }
parseSectionDirectiveDyld(StringRef,SMLoc)273   bool parseSectionDirectiveDyld(StringRef, SMLoc) {
274     return parseSectionSwitch("__DATA", "__dyld");
275   }
parseSectionDirectiveModInitFunc(StringRef,SMLoc)276   bool parseSectionDirectiveModInitFunc(StringRef, SMLoc) {
277     return parseSectionSwitch("__DATA", "__mod_init_func",
278                               MachO::S_MOD_INIT_FUNC_POINTERS, 4);
279   }
parseSectionDirectiveModTermFunc(StringRef,SMLoc)280   bool parseSectionDirectiveModTermFunc(StringRef, SMLoc) {
281     return parseSectionSwitch("__DATA", "__mod_term_func",
282                               MachO::S_MOD_TERM_FUNC_POINTERS, 4);
283   }
parseSectionDirectiveConstData(StringRef,SMLoc)284   bool parseSectionDirectiveConstData(StringRef, SMLoc) {
285     return parseSectionSwitch("__DATA", "__const");
286   }
parseSectionDirectiveObjCClass(StringRef,SMLoc)287   bool parseSectionDirectiveObjCClass(StringRef, SMLoc) {
288     return parseSectionSwitch("__OBJC", "__class",
289                               MachO::S_ATTR_NO_DEAD_STRIP);
290   }
parseSectionDirectiveObjCMetaClass(StringRef,SMLoc)291   bool parseSectionDirectiveObjCMetaClass(StringRef, SMLoc) {
292     return parseSectionSwitch("__OBJC", "__meta_class",
293                               MachO::S_ATTR_NO_DEAD_STRIP);
294   }
parseSectionDirectiveObjCCatClsMeth(StringRef,SMLoc)295   bool parseSectionDirectiveObjCCatClsMeth(StringRef, SMLoc) {
296     return parseSectionSwitch("__OBJC", "__cat_cls_meth",
297                               MachO::S_ATTR_NO_DEAD_STRIP);
298   }
parseSectionDirectiveObjCCatInstMeth(StringRef,SMLoc)299   bool parseSectionDirectiveObjCCatInstMeth(StringRef, SMLoc) {
300     return parseSectionSwitch("__OBJC", "__cat_inst_meth",
301                               MachO::S_ATTR_NO_DEAD_STRIP);
302   }
parseSectionDirectiveObjCProtocol(StringRef,SMLoc)303   bool parseSectionDirectiveObjCProtocol(StringRef, SMLoc) {
304     return parseSectionSwitch("__OBJC", "__protocol",
305                               MachO::S_ATTR_NO_DEAD_STRIP);
306   }
parseSectionDirectiveObjCStringObject(StringRef,SMLoc)307   bool parseSectionDirectiveObjCStringObject(StringRef, SMLoc) {
308     return parseSectionSwitch("__OBJC", "__string_object",
309                               MachO::S_ATTR_NO_DEAD_STRIP);
310   }
parseSectionDirectiveObjCClsMeth(StringRef,SMLoc)311   bool parseSectionDirectiveObjCClsMeth(StringRef, SMLoc) {
312     return parseSectionSwitch("__OBJC", "__cls_meth",
313                               MachO::S_ATTR_NO_DEAD_STRIP);
314   }
parseSectionDirectiveObjCInstMeth(StringRef,SMLoc)315   bool parseSectionDirectiveObjCInstMeth(StringRef, SMLoc) {
316     return parseSectionSwitch("__OBJC", "__inst_meth",
317                               MachO::S_ATTR_NO_DEAD_STRIP);
318   }
parseSectionDirectiveObjCClsRefs(StringRef,SMLoc)319   bool parseSectionDirectiveObjCClsRefs(StringRef, SMLoc) {
320     return parseSectionSwitch("__OBJC", "__cls_refs",
321                               MachO::S_ATTR_NO_DEAD_STRIP |
322                               MachO::S_LITERAL_POINTERS, 4);
323   }
parseSectionDirectiveObjCMessageRefs(StringRef,SMLoc)324   bool parseSectionDirectiveObjCMessageRefs(StringRef, SMLoc) {
325     return parseSectionSwitch("__OBJC", "__message_refs",
326                               MachO::S_ATTR_NO_DEAD_STRIP |
327                               MachO::S_LITERAL_POINTERS, 4);
328   }
parseSectionDirectiveObjCSymbols(StringRef,SMLoc)329   bool parseSectionDirectiveObjCSymbols(StringRef, SMLoc) {
330     return parseSectionSwitch("__OBJC", "__symbols",
331                               MachO::S_ATTR_NO_DEAD_STRIP);
332   }
parseSectionDirectiveObjCCategory(StringRef,SMLoc)333   bool parseSectionDirectiveObjCCategory(StringRef, SMLoc) {
334     return parseSectionSwitch("__OBJC", "__category",
335                               MachO::S_ATTR_NO_DEAD_STRIP);
336   }
parseSectionDirectiveObjCClassVars(StringRef,SMLoc)337   bool parseSectionDirectiveObjCClassVars(StringRef, SMLoc) {
338     return parseSectionSwitch("__OBJC", "__class_vars",
339                               MachO::S_ATTR_NO_DEAD_STRIP);
340   }
parseSectionDirectiveObjCInstanceVars(StringRef,SMLoc)341   bool parseSectionDirectiveObjCInstanceVars(StringRef, SMLoc) {
342     return parseSectionSwitch("__OBJC", "__instance_vars",
343                               MachO::S_ATTR_NO_DEAD_STRIP);
344   }
parseSectionDirectiveObjCModuleInfo(StringRef,SMLoc)345   bool parseSectionDirectiveObjCModuleInfo(StringRef, SMLoc) {
346     return parseSectionSwitch("__OBJC", "__module_info",
347                               MachO::S_ATTR_NO_DEAD_STRIP);
348   }
parseSectionDirectiveObjCClassNames(StringRef,SMLoc)349   bool parseSectionDirectiveObjCClassNames(StringRef, SMLoc) {
350     return parseSectionSwitch("__TEXT", "__cstring",
351                               MachO::S_CSTRING_LITERALS);
352   }
parseSectionDirectiveObjCMethVarTypes(StringRef,SMLoc)353   bool parseSectionDirectiveObjCMethVarTypes(StringRef, SMLoc) {
354     return parseSectionSwitch("__TEXT", "__cstring",
355                               MachO::S_CSTRING_LITERALS);
356   }
parseSectionDirectiveObjCMethVarNames(StringRef,SMLoc)357   bool parseSectionDirectiveObjCMethVarNames(StringRef, SMLoc) {
358     return parseSectionSwitch("__TEXT", "__cstring",
359                               MachO::S_CSTRING_LITERALS);
360   }
parseSectionDirectiveObjCSelectorStrs(StringRef,SMLoc)361   bool parseSectionDirectiveObjCSelectorStrs(StringRef, SMLoc) {
362     return parseSectionSwitch("__OBJC", "__selector_strs",
363                               MachO::S_CSTRING_LITERALS);
364   }
parseSectionDirectiveTData(StringRef,SMLoc)365   bool parseSectionDirectiveTData(StringRef, SMLoc) {
366     return parseSectionSwitch("__DATA", "__thread_data",
367                               MachO::S_THREAD_LOCAL_REGULAR);
368   }
parseSectionDirectiveText(StringRef,SMLoc)369   bool parseSectionDirectiveText(StringRef, SMLoc) {
370     return parseSectionSwitch("__TEXT", "__text",
371                               MachO::S_ATTR_PURE_INSTRUCTIONS);
372   }
parseSectionDirectiveTLV(StringRef,SMLoc)373   bool parseSectionDirectiveTLV(StringRef, SMLoc) {
374     return parseSectionSwitch("__DATA", "__thread_vars",
375                               MachO::S_THREAD_LOCAL_VARIABLES);
376   }
parseSectionDirectiveIdent(StringRef,SMLoc)377   bool parseSectionDirectiveIdent(StringRef, SMLoc) {
378     // Darwin silently ignores the .ident directive.
379     getParser().eatToEndOfStatement();
380     return false;
381   }
parseSectionDirectiveThreadInitFunc(StringRef,SMLoc)382   bool parseSectionDirectiveThreadInitFunc(StringRef, SMLoc) {
383     return parseSectionSwitch("__DATA", "__thread_init",
384                          MachO::S_THREAD_LOCAL_INIT_FUNCTION_POINTERS);
385   }
386   bool parseVersionMin(StringRef, SMLoc);
387 
388 };
389 
390 } // end anonymous namespace
391 
parseSectionSwitch(const char * Segment,const char * Section,unsigned TAA,unsigned Align,unsigned StubSize)392 bool DarwinAsmParser::parseSectionSwitch(const char *Segment,
393                                          const char *Section,
394                                          unsigned TAA, unsigned Align,
395                                          unsigned StubSize) {
396   if (getLexer().isNot(AsmToken::EndOfStatement))
397     return TokError("unexpected token in section switching directive");
398   Lex();
399 
400   // FIXME: Arch specific.
401   bool isText = TAA & MachO::S_ATTR_PURE_INSTRUCTIONS;
402   getStreamer().SwitchSection(getContext().getMachOSection(
403       Segment, Section, TAA, StubSize,
404       isText ? SectionKind::getText() : SectionKind::getData()));
405 
406   // Set the implicit alignment, if any.
407   //
408   // FIXME: This isn't really what 'as' does; I think it just uses the implicit
409   // alignment on the section (e.g., if one manually inserts bytes into the
410   // section, then just issuing the section switch directive will not realign
411   // the section. However, this is arguably more reasonable behavior, and there
412   // is no good reason for someone to intentionally emit incorrectly sized
413   // values into the implicitly aligned sections.
414   if (Align)
415     getStreamer().EmitValueToAlignment(Align);
416 
417   return false;
418 }
419 
420 /// parseDirectiveAltEntry
421 ///  ::= .alt_entry identifier
parseDirectiveAltEntry(StringRef,SMLoc)422 bool DarwinAsmParser::parseDirectiveAltEntry(StringRef, SMLoc) {
423   StringRef Name;
424   if (getParser().parseIdentifier(Name))
425     return TokError("expected identifier in directive");
426 
427   // Look up symbol.
428   MCSymbol *Sym = getContext().getOrCreateSymbol(Name);
429 
430   if (Sym->isDefined())
431     return TokError(".alt_entry must preceed symbol definition");
432 
433   if (!getStreamer().EmitSymbolAttribute(Sym, MCSA_AltEntry))
434     return TokError("unable to emit symbol attribute");
435 
436   Lex();
437   return false;
438 }
439 
440 /// parseDirectiveDesc
441 ///  ::= .desc identifier , expression
parseDirectiveDesc(StringRef,SMLoc)442 bool DarwinAsmParser::parseDirectiveDesc(StringRef, SMLoc) {
443   StringRef Name;
444   if (getParser().parseIdentifier(Name))
445     return TokError("expected identifier in directive");
446 
447   // Handle the identifier as the key symbol.
448   MCSymbol *Sym = getContext().getOrCreateSymbol(Name);
449 
450   if (getLexer().isNot(AsmToken::Comma))
451     return TokError("unexpected token in '.desc' directive");
452   Lex();
453 
454   int64_t DescValue;
455   if (getParser().parseAbsoluteExpression(DescValue))
456     return true;
457 
458   if (getLexer().isNot(AsmToken::EndOfStatement))
459     return TokError("unexpected token in '.desc' directive");
460 
461   Lex();
462 
463   // Set the n_desc field of this Symbol to this DescValue
464   getStreamer().EmitSymbolDesc(Sym, DescValue);
465 
466   return false;
467 }
468 
469 /// parseDirectiveIndirectSymbol
470 ///  ::= .indirect_symbol identifier
parseDirectiveIndirectSymbol(StringRef,SMLoc Loc)471 bool DarwinAsmParser::parseDirectiveIndirectSymbol(StringRef, SMLoc Loc) {
472   const MCSectionMachO *Current = static_cast<const MCSectionMachO*>(
473                                        getStreamer().getCurrentSection().first);
474   MachO::SectionType SectionType = Current->getType();
475   if (SectionType != MachO::S_NON_LAZY_SYMBOL_POINTERS &&
476       SectionType != MachO::S_LAZY_SYMBOL_POINTERS &&
477       SectionType != MachO::S_THREAD_LOCAL_VARIABLE_POINTERS &&
478       SectionType != MachO::S_SYMBOL_STUBS)
479     return Error(Loc, "indirect symbol not in a symbol pointer or stub "
480                       "section");
481 
482   StringRef Name;
483   if (getParser().parseIdentifier(Name))
484     return TokError("expected identifier in .indirect_symbol directive");
485 
486   MCSymbol *Sym = getContext().getOrCreateSymbol(Name);
487 
488   // Assembler local symbols don't make any sense here. Complain loudly.
489   if (Sym->isTemporary())
490     return TokError("non-local symbol required in directive");
491 
492   if (!getStreamer().EmitSymbolAttribute(Sym, MCSA_IndirectSymbol))
493     return TokError("unable to emit indirect symbol attribute for: " + Name);
494 
495   if (getLexer().isNot(AsmToken::EndOfStatement))
496     return TokError("unexpected token in '.indirect_symbol' directive");
497 
498   Lex();
499 
500   return false;
501 }
502 
503 /// parseDirectiveDumpOrLoad
504 ///  ::= ( .dump | .load ) "filename"
parseDirectiveDumpOrLoad(StringRef Directive,SMLoc IDLoc)505 bool DarwinAsmParser::parseDirectiveDumpOrLoad(StringRef Directive,
506                                                SMLoc IDLoc) {
507   bool IsDump = Directive == ".dump";
508   if (getLexer().isNot(AsmToken::String))
509     return TokError("expected string in '.dump' or '.load' directive");
510 
511   Lex();
512 
513   if (getLexer().isNot(AsmToken::EndOfStatement))
514     return TokError("unexpected token in '.dump' or '.load' directive");
515 
516   Lex();
517 
518   // FIXME: If/when .dump and .load are implemented they will be done in the
519   // the assembly parser and not have any need for an MCStreamer API.
520   if (IsDump)
521     return Warning(IDLoc, "ignoring directive .dump for now");
522   else
523     return Warning(IDLoc, "ignoring directive .load for now");
524 }
525 
526 /// ParseDirectiveLinkerOption
527 ///  ::= .linker_option "string" ( , "string" )*
parseDirectiveLinkerOption(StringRef IDVal,SMLoc)528 bool DarwinAsmParser::parseDirectiveLinkerOption(StringRef IDVal, SMLoc) {
529   SmallVector<std::string, 4> Args;
530   for (;;) {
531     if (getLexer().isNot(AsmToken::String))
532       return TokError("expected string in '" + Twine(IDVal) + "' directive");
533 
534     std::string Data;
535     if (getParser().parseEscapedString(Data))
536       return true;
537 
538     Args.push_back(Data);
539 
540     Lex();
541     if (getLexer().is(AsmToken::EndOfStatement))
542       break;
543 
544     if (getLexer().isNot(AsmToken::Comma))
545       return TokError("unexpected token in '" + Twine(IDVal) + "' directive");
546     Lex();
547   }
548 
549   getStreamer().EmitLinkerOptions(Args);
550   return false;
551 }
552 
553 /// parseDirectiveLsym
554 ///  ::= .lsym identifier , expression
parseDirectiveLsym(StringRef,SMLoc)555 bool DarwinAsmParser::parseDirectiveLsym(StringRef, SMLoc) {
556   StringRef Name;
557   if (getParser().parseIdentifier(Name))
558     return TokError("expected identifier in directive");
559 
560   // Handle the identifier as the key symbol.
561   MCSymbol *Sym = getContext().getOrCreateSymbol(Name);
562 
563   if (getLexer().isNot(AsmToken::Comma))
564     return TokError("unexpected token in '.lsym' directive");
565   Lex();
566 
567   const MCExpr *Value;
568   if (getParser().parseExpression(Value))
569     return true;
570 
571   if (getLexer().isNot(AsmToken::EndOfStatement))
572     return TokError("unexpected token in '.lsym' directive");
573 
574   Lex();
575 
576   // We don't currently support this directive.
577   //
578   // FIXME: Diagnostic location!
579   (void) Sym;
580   return TokError("directive '.lsym' is unsupported");
581 }
582 
583 /// parseDirectiveSection:
584 ///   ::= .section identifier (',' identifier)*
parseDirectiveSection(StringRef,SMLoc)585 bool DarwinAsmParser::parseDirectiveSection(StringRef, SMLoc) {
586   SMLoc Loc = getLexer().getLoc();
587 
588   StringRef SectionName;
589   if (getParser().parseIdentifier(SectionName))
590     return Error(Loc, "expected identifier after '.section' directive");
591 
592   // Verify there is a following comma.
593   if (!getLexer().is(AsmToken::Comma))
594     return TokError("unexpected token in '.section' directive");
595 
596   std::string SectionSpec = SectionName;
597   SectionSpec += ",";
598 
599   // Add all the tokens until the end of the line, ParseSectionSpecifier will
600   // handle this.
601   StringRef EOL = getLexer().LexUntilEndOfStatement();
602   SectionSpec.append(EOL.begin(), EOL.end());
603 
604   Lex();
605   if (getLexer().isNot(AsmToken::EndOfStatement))
606     return TokError("unexpected token in '.section' directive");
607   Lex();
608 
609 
610   StringRef Segment, Section;
611   unsigned StubSize;
612   unsigned TAA;
613   bool TAAParsed;
614   std::string ErrorStr =
615     MCSectionMachO::ParseSectionSpecifier(SectionSpec, Segment, Section,
616                                           TAA, TAAParsed, StubSize);
617 
618   if (!ErrorStr.empty())
619     return Error(Loc, ErrorStr.c_str());
620 
621   // Issue a warning if the target is not powerpc and Section is a *coal* section.
622   Triple TT = getParser().getContext().getObjectFileInfo()->getTargetTriple();
623   Triple::ArchType ArchTy = TT.getArch();
624 
625   if (ArchTy != Triple::ppc && ArchTy != Triple::ppc64) {
626     StringRef NonCoalSection = StringSwitch<StringRef>(Section)
627                                    .Case("__textcoal_nt", "__text")
628                                    .Case("__const_coal", "__const")
629                                    .Case("__datacoal_nt", "__data")
630                                    .Default(Section);
631 
632     if (!Section.equals(NonCoalSection)) {
633       StringRef SectionVal(Loc.getPointer());
634       size_t B = SectionVal.find(',') + 1, E = SectionVal.find(',', B);
635       SMLoc BLoc = SMLoc::getFromPointer(SectionVal.data() + B);
636       SMLoc ELoc = SMLoc::getFromPointer(SectionVal.data() + E);
637       getParser().Warning(Loc, "section \"" + Section + "\" is deprecated",
638                           SMRange(BLoc, ELoc));
639       getParser().Note(Loc, "change section name to \"" + NonCoalSection +
640                        "\"", SMRange(BLoc, ELoc));
641     }
642   }
643 
644   // FIXME: Arch specific.
645   bool isText = Segment == "__TEXT";  // FIXME: Hack.
646   getStreamer().SwitchSection(getContext().getMachOSection(
647       Segment, Section, TAA, StubSize,
648       isText ? SectionKind::getText() : SectionKind::getData()));
649   return false;
650 }
651 
652 /// ParseDirectivePushSection:
653 ///   ::= .pushsection identifier (',' identifier)*
parseDirectivePushSection(StringRef S,SMLoc Loc)654 bool DarwinAsmParser::parseDirectivePushSection(StringRef S, SMLoc Loc) {
655   getStreamer().PushSection();
656 
657   if (parseDirectiveSection(S, Loc)) {
658     getStreamer().PopSection();
659     return true;
660   }
661 
662   return false;
663 }
664 
665 /// ParseDirectivePopSection:
666 ///   ::= .popsection
parseDirectivePopSection(StringRef,SMLoc)667 bool DarwinAsmParser::parseDirectivePopSection(StringRef, SMLoc) {
668   if (!getStreamer().PopSection())
669     return TokError(".popsection without corresponding .pushsection");
670   return false;
671 }
672 
673 /// ParseDirectivePrevious:
674 ///   ::= .previous
parseDirectivePrevious(StringRef DirName,SMLoc)675 bool DarwinAsmParser::parseDirectivePrevious(StringRef DirName, SMLoc) {
676   MCSectionSubPair PreviousSection = getStreamer().getPreviousSection();
677   if (!PreviousSection.first)
678     return TokError(".previous without corresponding .section");
679   getStreamer().SwitchSection(PreviousSection.first, PreviousSection.second);
680   return false;
681 }
682 
683 /// ParseDirectiveSecureLogUnique
684 ///  ::= .secure_log_unique ... message ...
parseDirectiveSecureLogUnique(StringRef,SMLoc IDLoc)685 bool DarwinAsmParser::parseDirectiveSecureLogUnique(StringRef, SMLoc IDLoc) {
686   StringRef LogMessage = getParser().parseStringToEndOfStatement();
687   if (getLexer().isNot(AsmToken::EndOfStatement))
688     return TokError("unexpected token in '.secure_log_unique' directive");
689 
690   if (getContext().getSecureLogUsed())
691     return Error(IDLoc, ".secure_log_unique specified multiple times");
692 
693   // Get the secure log path.
694   const char *SecureLogFile = getContext().getSecureLogFile();
695   if (!SecureLogFile)
696     return Error(IDLoc, ".secure_log_unique used but AS_SECURE_LOG_FILE "
697                  "environment variable unset.");
698 
699   // Open the secure log file if we haven't already.
700   raw_fd_ostream *OS = getContext().getSecureLog();
701   if (!OS) {
702     std::error_code EC;
703     auto NewOS = llvm::make_unique<raw_fd_ostream>(
704         SecureLogFile, EC, sys::fs::F_Append | sys::fs::F_Text);
705     if (EC)
706        return Error(IDLoc, Twine("can't open secure log file: ") +
707                                SecureLogFile + " (" + EC.message() + ")");
708     OS = NewOS.get();
709     getContext().setSecureLog(std::move(NewOS));
710   }
711 
712   // Write the message.
713   unsigned CurBuf = getSourceManager().FindBufferContainingLoc(IDLoc);
714   *OS << getSourceManager().getBufferInfo(CurBuf).Buffer->getBufferIdentifier()
715       << ":" << getSourceManager().FindLineNumber(IDLoc, CurBuf) << ":"
716       << LogMessage + "\n";
717 
718   getContext().setSecureLogUsed(true);
719 
720   return false;
721 }
722 
723 /// ParseDirectiveSecureLogReset
724 ///  ::= .secure_log_reset
parseDirectiveSecureLogReset(StringRef,SMLoc IDLoc)725 bool DarwinAsmParser::parseDirectiveSecureLogReset(StringRef, SMLoc IDLoc) {
726   if (getLexer().isNot(AsmToken::EndOfStatement))
727     return TokError("unexpected token in '.secure_log_reset' directive");
728 
729   Lex();
730 
731   getContext().setSecureLogUsed(false);
732 
733   return false;
734 }
735 
736 /// parseDirectiveSubsectionsViaSymbols
737 ///  ::= .subsections_via_symbols
parseDirectiveSubsectionsViaSymbols(StringRef,SMLoc)738 bool DarwinAsmParser::parseDirectiveSubsectionsViaSymbols(StringRef, SMLoc) {
739   if (getLexer().isNot(AsmToken::EndOfStatement))
740     return TokError("unexpected token in '.subsections_via_symbols' directive");
741 
742   Lex();
743 
744   getStreamer().EmitAssemblerFlag(MCAF_SubsectionsViaSymbols);
745 
746   return false;
747 }
748 
749 /// ParseDirectiveTBSS
750 ///  ::= .tbss identifier, size, align
parseDirectiveTBSS(StringRef,SMLoc)751 bool DarwinAsmParser::parseDirectiveTBSS(StringRef, SMLoc) {
752   SMLoc IDLoc = getLexer().getLoc();
753   StringRef Name;
754   if (getParser().parseIdentifier(Name))
755     return TokError("expected identifier in directive");
756 
757   // Handle the identifier as the key symbol.
758   MCSymbol *Sym = getContext().getOrCreateSymbol(Name);
759 
760   if (getLexer().isNot(AsmToken::Comma))
761     return TokError("unexpected token in directive");
762   Lex();
763 
764   int64_t Size;
765   SMLoc SizeLoc = getLexer().getLoc();
766   if (getParser().parseAbsoluteExpression(Size))
767     return true;
768 
769   int64_t Pow2Alignment = 0;
770   SMLoc Pow2AlignmentLoc;
771   if (getLexer().is(AsmToken::Comma)) {
772     Lex();
773     Pow2AlignmentLoc = getLexer().getLoc();
774     if (getParser().parseAbsoluteExpression(Pow2Alignment))
775       return true;
776   }
777 
778   if (getLexer().isNot(AsmToken::EndOfStatement))
779     return TokError("unexpected token in '.tbss' directive");
780 
781   Lex();
782 
783   if (Size < 0)
784     return Error(SizeLoc, "invalid '.tbss' directive size, can't be less than"
785                  "zero");
786 
787   // FIXME: Diagnose overflow.
788   if (Pow2Alignment < 0)
789     return Error(Pow2AlignmentLoc, "invalid '.tbss' alignment, can't be less"
790                  "than zero");
791 
792   if (!Sym->isUndefined())
793     return Error(IDLoc, "invalid symbol redefinition");
794 
795   getStreamer().EmitTBSSSymbol(getContext().getMachOSection(
796                                  "__DATA", "__thread_bss",
797                                  MachO::S_THREAD_LOCAL_ZEROFILL,
798                                  0, SectionKind::getThreadBSS()),
799                                Sym, Size, 1 << Pow2Alignment);
800 
801   return false;
802 }
803 
804 /// ParseDirectiveZerofill
805 ///  ::= .zerofill segname , sectname [, identifier , size_expression [
806 ///      , align_expression ]]
parseDirectiveZerofill(StringRef,SMLoc)807 bool DarwinAsmParser::parseDirectiveZerofill(StringRef, SMLoc) {
808   StringRef Segment;
809   if (getParser().parseIdentifier(Segment))
810     return TokError("expected segment name after '.zerofill' directive");
811 
812   if (getLexer().isNot(AsmToken::Comma))
813     return TokError("unexpected token in directive");
814   Lex();
815 
816   StringRef Section;
817   if (getParser().parseIdentifier(Section))
818     return TokError("expected section name after comma in '.zerofill' "
819                     "directive");
820 
821   // If this is the end of the line all that was wanted was to create the
822   // the section but with no symbol.
823   if (getLexer().is(AsmToken::EndOfStatement)) {
824     // Create the zerofill section but no symbol
825     getStreamer().EmitZerofill(getContext().getMachOSection(
826                                  Segment, Section, MachO::S_ZEROFILL,
827                                  0, SectionKind::getBSS()));
828     return false;
829   }
830 
831   if (getLexer().isNot(AsmToken::Comma))
832     return TokError("unexpected token in directive");
833   Lex();
834 
835   SMLoc IDLoc = getLexer().getLoc();
836   StringRef IDStr;
837   if (getParser().parseIdentifier(IDStr))
838     return TokError("expected identifier in directive");
839 
840   // handle the identifier as the key symbol.
841   MCSymbol *Sym = getContext().getOrCreateSymbol(IDStr);
842 
843   if (getLexer().isNot(AsmToken::Comma))
844     return TokError("unexpected token in directive");
845   Lex();
846 
847   int64_t Size;
848   SMLoc SizeLoc = getLexer().getLoc();
849   if (getParser().parseAbsoluteExpression(Size))
850     return true;
851 
852   int64_t Pow2Alignment = 0;
853   SMLoc Pow2AlignmentLoc;
854   if (getLexer().is(AsmToken::Comma)) {
855     Lex();
856     Pow2AlignmentLoc = getLexer().getLoc();
857     if (getParser().parseAbsoluteExpression(Pow2Alignment))
858       return true;
859   }
860 
861   if (getLexer().isNot(AsmToken::EndOfStatement))
862     return TokError("unexpected token in '.zerofill' directive");
863 
864   Lex();
865 
866   if (Size < 0)
867     return Error(SizeLoc, "invalid '.zerofill' directive size, can't be less "
868                  "than zero");
869 
870   // NOTE: The alignment in the directive is a power of 2 value, the assembler
871   // may internally end up wanting an alignment in bytes.
872   // FIXME: Diagnose overflow.
873   if (Pow2Alignment < 0)
874     return Error(Pow2AlignmentLoc, "invalid '.zerofill' directive alignment, "
875                  "can't be less than zero");
876 
877   if (!Sym->isUndefined())
878     return Error(IDLoc, "invalid symbol redefinition");
879 
880   // Create the zerofill Symbol with Size and Pow2Alignment
881   //
882   // FIXME: Arch specific.
883   getStreamer().EmitZerofill(getContext().getMachOSection(
884                                Segment, Section, MachO::S_ZEROFILL,
885                                0, SectionKind::getBSS()),
886                              Sym, Size, 1 << Pow2Alignment);
887 
888   return false;
889 }
890 
891 /// ParseDirectiveDataRegion
892 ///  ::= .data_region [ ( jt8 | jt16 | jt32 ) ]
parseDirectiveDataRegion(StringRef,SMLoc)893 bool DarwinAsmParser::parseDirectiveDataRegion(StringRef, SMLoc) {
894   if (getLexer().is(AsmToken::EndOfStatement)) {
895     Lex();
896     getStreamer().EmitDataRegion(MCDR_DataRegion);
897     return false;
898   }
899   StringRef RegionType;
900   SMLoc Loc = getParser().getTok().getLoc();
901   if (getParser().parseIdentifier(RegionType))
902     return TokError("expected region type after '.data_region' directive");
903   int Kind = StringSwitch<int>(RegionType)
904     .Case("jt8", MCDR_DataRegionJT8)
905     .Case("jt16", MCDR_DataRegionJT16)
906     .Case("jt32", MCDR_DataRegionJT32)
907     .Default(-1);
908   if (Kind == -1)
909     return Error(Loc, "unknown region type in '.data_region' directive");
910   Lex();
911 
912   getStreamer().EmitDataRegion((MCDataRegionType)Kind);
913   return false;
914 }
915 
916 /// ParseDirectiveDataRegionEnd
917 ///  ::= .end_data_region
parseDirectiveDataRegionEnd(StringRef,SMLoc)918 bool DarwinAsmParser::parseDirectiveDataRegionEnd(StringRef, SMLoc) {
919   if (getLexer().isNot(AsmToken::EndOfStatement))
920     return TokError("unexpected token in '.end_data_region' directive");
921 
922   Lex();
923   getStreamer().EmitDataRegion(MCDR_DataRegionEnd);
924   return false;
925 }
926 
927 /// parseVersionMin
928 ///  ::= .ios_version_min major,minor[,update]
929 ///  ::= .macosx_version_min major,minor[,update]
parseVersionMin(StringRef Directive,SMLoc Loc)930 bool DarwinAsmParser::parseVersionMin(StringRef Directive, SMLoc Loc) {
931   int64_t Major = 0, Minor = 0, Update = 0;
932   int Kind = StringSwitch<int>(Directive)
933     .Case(".watchos_version_min", MCVM_WatchOSVersionMin)
934     .Case(".tvos_version_min", MCVM_TvOSVersionMin)
935     .Case(".ios_version_min", MCVM_IOSVersionMin)
936     .Case(".macosx_version_min", MCVM_OSXVersionMin);
937   // Get the major version number.
938   if (getLexer().isNot(AsmToken::Integer))
939     return TokError("invalid OS major version number");
940   Major = getLexer().getTok().getIntVal();
941   if (Major > 65535 || Major <= 0)
942     return TokError("invalid OS major version number");
943   Lex();
944   if (getLexer().isNot(AsmToken::Comma))
945     return TokError("minor OS version number required, comma expected");
946   Lex();
947   // Get the minor version number.
948   if (getLexer().isNot(AsmToken::Integer))
949     return TokError("invalid OS minor version number");
950   Minor = getLexer().getTok().getIntVal();
951   if (Minor > 255 || Minor < 0)
952     return TokError("invalid OS minor version number");
953   Lex();
954   // Get the update level, if specified
955   if (getLexer().isNot(AsmToken::EndOfStatement)) {
956     if (getLexer().isNot(AsmToken::Comma))
957       return TokError("invalid update specifier, comma expected");
958     Lex();
959     if (getLexer().isNot(AsmToken::Integer))
960       return TokError("invalid OS update number");
961     Update = getLexer().getTok().getIntVal();
962     if (Update > 255 || Update < 0)
963       return TokError("invalid OS update number");
964     Lex();
965   }
966 
967   const Triple &T = getContext().getObjectFileInfo()->getTargetTriple();
968   Triple::OSType ExpectedOS = Triple::UnknownOS;
969   switch ((MCVersionMinType)Kind) {
970   case MCVM_WatchOSVersionMin: ExpectedOS = Triple::WatchOS; break;
971   case MCVM_TvOSVersionMin:    ExpectedOS = Triple::TvOS;    break;
972   case MCVM_IOSVersionMin:     ExpectedOS = Triple::IOS;     break;
973   case MCVM_OSXVersionMin:     ExpectedOS = Triple::MacOSX;  break;
974   }
975   if (T.getOS() != ExpectedOS)
976     Warning(Loc, Directive + " should only be used for " +
977             Triple::getOSTypeName(ExpectedOS) + " targets");
978 
979   if (LastVersionMinDirective.isValid()) {
980     Warning(Loc, "overriding previous version_min directive");
981     Note(LastVersionMinDirective, "previous definition is here");
982   }
983   LastVersionMinDirective = Loc;
984 
985   // We've parsed a correct version specifier, so send it to the streamer.
986   getStreamer().EmitVersionMin((MCVersionMinType)Kind, Major, Minor, Update);
987 
988   return false;
989 }
990 
991 namespace llvm {
992 
createDarwinAsmParser()993 MCAsmParserExtension *createDarwinAsmParser() {
994   return new DarwinAsmParser;
995 }
996 
997 } // end llvm namespace
998