1 //===- DarwinAsmParser.cpp - Darwin (Mach-O) Assembly Parser --------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #include "llvm/ADT/SmallVector.h"
10 #include "llvm/ADT/StringRef.h"
11 #include "llvm/ADT/StringSwitch.h"
12 #include "llvm/ADT/Triple.h"
13 #include "llvm/ADT/Twine.h"
14 #include "llvm/BinaryFormat/MachO.h"
15 #include "llvm/MC/MCContext.h"
16 #include "llvm/MC/MCDirectives.h"
17 #include "llvm/MC/MCParser/MCAsmLexer.h"
18 #include "llvm/MC/MCParser/MCAsmParser.h"
19 #include "llvm/MC/MCParser/MCAsmParserExtension.h"
20 #include "llvm/MC/MCSectionMachO.h"
21 #include "llvm/MC/MCStreamer.h"
22 #include "llvm/MC/MCSymbol.h"
23 #include "llvm/MC/SectionKind.h"
24 #include "llvm/Support/Error.h"
25 #include "llvm/Support/FileSystem.h"
26 #include "llvm/Support/MemoryBuffer.h"
27 #include "llvm/Support/SMLoc.h"
28 #include "llvm/Support/SourceMgr.h"
29 #include "llvm/Support/raw_ostream.h"
30 #include <cstddef>
31 #include <cstdint>
32 #include <string>
33 #include <system_error>
34 #include <utility>
35 
36 using namespace llvm;
37 
38 namespace {
39 
40 /// Implementation of directive handling which is shared across all
41 /// Darwin targets.
42 class DarwinAsmParser : public MCAsmParserExtension {
43   template<bool (DarwinAsmParser::*HandlerMethod)(StringRef, SMLoc)>
44   void addDirectiveHandler(StringRef Directive) {
45     MCAsmParser::ExtensionDirectiveHandler Handler = std::make_pair(
46         this, HandleDirective<DarwinAsmParser, HandlerMethod>);
47     getParser().addDirectiveHandler(Directive, Handler);
48   }
49 
50   bool parseSectionSwitch(StringRef Segment, StringRef Section,
51                           unsigned TAA = 0, unsigned ImplicitAlign = 0,
52                           unsigned StubSize = 0);
53 
54   SMLoc LastVersionDirective;
55 
56 public:
57   DarwinAsmParser() = default;
58 
59   void Initialize(MCAsmParser &Parser) override {
60     // Call the base implementation.
61     this->MCAsmParserExtension::Initialize(Parser);
62 
63     addDirectiveHandler<&DarwinAsmParser::parseDirectiveAltEntry>(".alt_entry");
64     addDirectiveHandler<&DarwinAsmParser::parseDirectiveDesc>(".desc");
65     addDirectiveHandler<&DarwinAsmParser::parseDirectiveIndirectSymbol>(
66       ".indirect_symbol");
67     addDirectiveHandler<&DarwinAsmParser::parseDirectiveLsym>(".lsym");
68     addDirectiveHandler<&DarwinAsmParser::parseDirectiveSubsectionsViaSymbols>(
69       ".subsections_via_symbols");
70     addDirectiveHandler<&DarwinAsmParser::parseDirectiveDumpOrLoad>(".dump");
71     addDirectiveHandler<&DarwinAsmParser::parseDirectiveDumpOrLoad>(".load");
72     addDirectiveHandler<&DarwinAsmParser::parseDirectiveSection>(".section");
73     addDirectiveHandler<&DarwinAsmParser::parseDirectivePushSection>(
74       ".pushsection");
75     addDirectiveHandler<&DarwinAsmParser::parseDirectivePopSection>(
76       ".popsection");
77     addDirectiveHandler<&DarwinAsmParser::parseDirectivePrevious>(".previous");
78     addDirectiveHandler<&DarwinAsmParser::parseDirectiveSecureLogUnique>(
79       ".secure_log_unique");
80     addDirectiveHandler<&DarwinAsmParser::parseDirectiveSecureLogReset>(
81       ".secure_log_reset");
82     addDirectiveHandler<&DarwinAsmParser::parseDirectiveTBSS>(".tbss");
83     addDirectiveHandler<&DarwinAsmParser::parseDirectiveZerofill>(".zerofill");
84 
85     addDirectiveHandler<&DarwinAsmParser::parseDirectiveDataRegion>(
86       ".data_region");
87     addDirectiveHandler<&DarwinAsmParser::parseDirectiveDataRegionEnd>(
88       ".end_data_region");
89 
90     // Special section directives.
91     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveBss>(".bss");
92     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveConst>(".const");
93     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveConstData>(
94       ".const_data");
95     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveConstructor>(
96       ".constructor");
97     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveCString>(
98       ".cstring");
99     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveData>(".data");
100     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveDestructor>(
101       ".destructor");
102     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveDyld>(".dyld");
103     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveFVMLibInit0>(
104       ".fvmlib_init0");
105     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveFVMLibInit1>(
106       ".fvmlib_init1");
107     addDirectiveHandler<
108       &DarwinAsmParser::parseSectionDirectiveLazySymbolPointers>(
109         ".lazy_symbol_pointer");
110     addDirectiveHandler<&DarwinAsmParser::parseDirectiveLinkerOption>(
111       ".linker_option");
112     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveLiteral16>(
113       ".literal16");
114     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveLiteral4>(
115       ".literal4");
116     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveLiteral8>(
117       ".literal8");
118     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveModInitFunc>(
119       ".mod_init_func");
120     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveModTermFunc>(
121       ".mod_term_func");
122     addDirectiveHandler<
123       &DarwinAsmParser::parseSectionDirectiveNonLazySymbolPointers>(
124         ".non_lazy_symbol_pointer");
125     addDirectiveHandler<
126       &DarwinAsmParser::parseSectionDirectiveThreadLocalVariablePointers>(
127         ".thread_local_variable_pointer");
128     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveObjCCatClsMeth>(
129       ".objc_cat_cls_meth");
130     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveObjCCatInstMeth>(
131       ".objc_cat_inst_meth");
132     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveObjCCategory>(
133       ".objc_category");
134     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveObjCClass>(
135       ".objc_class");
136     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveObjCClassNames>(
137       ".objc_class_names");
138     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveObjCClassVars>(
139       ".objc_class_vars");
140     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveObjCClsMeth>(
141       ".objc_cls_meth");
142     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveObjCClsRefs>(
143       ".objc_cls_refs");
144     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveObjCInstMeth>(
145       ".objc_inst_meth");
146     addDirectiveHandler<
147       &DarwinAsmParser::parseSectionDirectiveObjCInstanceVars>(
148         ".objc_instance_vars");
149     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveObjCMessageRefs>(
150       ".objc_message_refs");
151     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveObjCMetaClass>(
152       ".objc_meta_class");
153     addDirectiveHandler<
154       &DarwinAsmParser::parseSectionDirectiveObjCMethVarNames>(
155         ".objc_meth_var_names");
156     addDirectiveHandler<
157       &DarwinAsmParser::parseSectionDirectiveObjCMethVarTypes>(
158         ".objc_meth_var_types");
159     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveObjCModuleInfo>(
160       ".objc_module_info");
161     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveObjCProtocol>(
162       ".objc_protocol");
163     addDirectiveHandler<
164       &DarwinAsmParser::parseSectionDirectiveObjCSelectorStrs>(
165         ".objc_selector_strs");
166     addDirectiveHandler<
167       &DarwinAsmParser::parseSectionDirectiveObjCStringObject>(
168         ".objc_string_object");
169     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveObjCSymbols>(
170       ".objc_symbols");
171     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectivePICSymbolStub>(
172       ".picsymbol_stub");
173     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveStaticConst>(
174       ".static_const");
175     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveStaticData>(
176       ".static_data");
177     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveSymbolStub>(
178       ".symbol_stub");
179     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveTData>(".tdata");
180     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveText>(".text");
181     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveThreadInitFunc>(
182       ".thread_init_func");
183     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveTLV>(".tlv");
184 
185     addDirectiveHandler<&DarwinAsmParser::parseSectionDirectiveIdent>(".ident");
186     addDirectiveHandler<&DarwinAsmParser::parseWatchOSVersionMin>(
187       ".watchos_version_min");
188     addDirectiveHandler<&DarwinAsmParser::parseTvOSVersionMin>(
189       ".tvos_version_min");
190     addDirectiveHandler<&DarwinAsmParser::parseIOSVersionMin>(
191       ".ios_version_min");
192     addDirectiveHandler<&DarwinAsmParser::parseMacOSXVersionMin>(
193       ".macosx_version_min");
194     addDirectiveHandler<&DarwinAsmParser::parseBuildVersion>(".build_version");
195     addDirectiveHandler<&DarwinAsmParser::parseDirectiveCGProfile>(
196         ".cg_profile");
197 
198     LastVersionDirective = SMLoc();
199   }
200 
201   bool parseDirectiveAltEntry(StringRef, SMLoc);
202   bool parseDirectiveDesc(StringRef, SMLoc);
203   bool parseDirectiveIndirectSymbol(StringRef, SMLoc);
204   bool parseDirectiveDumpOrLoad(StringRef, SMLoc);
205   bool parseDirectiveLsym(StringRef, SMLoc);
206   bool parseDirectiveLinkerOption(StringRef, SMLoc);
207   bool parseDirectiveSection(StringRef, SMLoc);
208   bool parseDirectivePushSection(StringRef, SMLoc);
209   bool parseDirectivePopSection(StringRef, SMLoc);
210   bool parseDirectivePrevious(StringRef, SMLoc);
211   bool parseDirectiveSecureLogReset(StringRef, SMLoc);
212   bool parseDirectiveSecureLogUnique(StringRef, SMLoc);
213   bool parseDirectiveSubsectionsViaSymbols(StringRef, SMLoc);
214   bool parseDirectiveTBSS(StringRef, SMLoc);
215   bool parseDirectiveZerofill(StringRef, SMLoc);
216   bool parseDirectiveDataRegion(StringRef, SMLoc);
217   bool parseDirectiveDataRegionEnd(StringRef, SMLoc);
218 
219   // Named Section Directive
220   bool parseSectionDirectiveBss(StringRef, SMLoc) {
221     return parseSectionSwitch("__DATA", "__bss");
222   }
223 
224   bool parseSectionDirectiveConst(StringRef, SMLoc) {
225     return parseSectionSwitch("__TEXT", "__const");
226   }
227 
228   bool parseSectionDirectiveStaticConst(StringRef, SMLoc) {
229     return parseSectionSwitch("__TEXT", "__static_const");
230   }
231 
232   bool parseSectionDirectiveCString(StringRef, SMLoc) {
233     return parseSectionSwitch("__TEXT","__cstring",
234                               MachO::S_CSTRING_LITERALS);
235   }
236 
237   bool parseSectionDirectiveLiteral4(StringRef, SMLoc) {
238     return parseSectionSwitch("__TEXT", "__literal4",
239                               MachO::S_4BYTE_LITERALS, 4);
240   }
241 
242   bool parseSectionDirectiveLiteral8(StringRef, SMLoc) {
243     return parseSectionSwitch("__TEXT", "__literal8",
244                               MachO::S_8BYTE_LITERALS, 8);
245   }
246 
247   bool parseSectionDirectiveLiteral16(StringRef, SMLoc) {
248     return parseSectionSwitch("__TEXT","__literal16",
249                               MachO::S_16BYTE_LITERALS, 16);
250   }
251 
252   bool parseSectionDirectiveConstructor(StringRef, SMLoc) {
253     return parseSectionSwitch("__TEXT","__constructor");
254   }
255 
256   bool parseSectionDirectiveDestructor(StringRef, SMLoc) {
257     return parseSectionSwitch("__TEXT","__destructor");
258   }
259 
260   bool parseSectionDirectiveFVMLibInit0(StringRef, SMLoc) {
261     return parseSectionSwitch("__TEXT","__fvmlib_init0");
262   }
263 
264   bool parseSectionDirectiveFVMLibInit1(StringRef, SMLoc) {
265     return parseSectionSwitch("__TEXT","__fvmlib_init1");
266   }
267 
268   bool parseSectionDirectiveSymbolStub(StringRef, SMLoc) {
269     return parseSectionSwitch("__TEXT","__symbol_stub",
270                               MachO::S_SYMBOL_STUBS |
271                               MachO::S_ATTR_PURE_INSTRUCTIONS,
272                               // FIXME: Different on PPC and ARM.
273                               0, 16);
274   }
275 
276   bool parseSectionDirectivePICSymbolStub(StringRef, SMLoc) {
277     return parseSectionSwitch("__TEXT","__picsymbol_stub",
278                               MachO::S_SYMBOL_STUBS |
279                               MachO::S_ATTR_PURE_INSTRUCTIONS, 0, 26);
280   }
281 
282   bool parseSectionDirectiveData(StringRef, SMLoc) {
283     return parseSectionSwitch("__DATA", "__data");
284   }
285 
286   bool parseSectionDirectiveStaticData(StringRef, SMLoc) {
287     return parseSectionSwitch("__DATA", "__static_data");
288   }
289 
290   bool parseSectionDirectiveNonLazySymbolPointers(StringRef, SMLoc) {
291     return parseSectionSwitch("__DATA", "__nl_symbol_ptr",
292                               MachO::S_NON_LAZY_SYMBOL_POINTERS, 4);
293   }
294 
295   bool parseSectionDirectiveLazySymbolPointers(StringRef, SMLoc) {
296     return parseSectionSwitch("__DATA", "__la_symbol_ptr",
297                               MachO::S_LAZY_SYMBOL_POINTERS, 4);
298   }
299 
300   bool parseSectionDirectiveThreadLocalVariablePointers(StringRef, SMLoc) {
301     return parseSectionSwitch("__DATA", "__thread_ptr",
302                               MachO::S_THREAD_LOCAL_VARIABLE_POINTERS, 4);
303   }
304 
305   bool parseSectionDirectiveDyld(StringRef, SMLoc) {
306     return parseSectionSwitch("__DATA", "__dyld");
307   }
308 
309   bool parseSectionDirectiveModInitFunc(StringRef, SMLoc) {
310     return parseSectionSwitch("__DATA", "__mod_init_func",
311                               MachO::S_MOD_INIT_FUNC_POINTERS, 4);
312   }
313 
314   bool parseSectionDirectiveModTermFunc(StringRef, SMLoc) {
315     return parseSectionSwitch("__DATA", "__mod_term_func",
316                               MachO::S_MOD_TERM_FUNC_POINTERS, 4);
317   }
318 
319   bool parseSectionDirectiveConstData(StringRef, SMLoc) {
320     return parseSectionSwitch("__DATA", "__const");
321   }
322 
323   bool parseSectionDirectiveObjCClass(StringRef, SMLoc) {
324     return parseSectionSwitch("__OBJC", "__class",
325                               MachO::S_ATTR_NO_DEAD_STRIP);
326   }
327 
328   bool parseSectionDirectiveObjCMetaClass(StringRef, SMLoc) {
329     return parseSectionSwitch("__OBJC", "__meta_class",
330                               MachO::S_ATTR_NO_DEAD_STRIP);
331   }
332 
333   bool parseSectionDirectiveObjCCatClsMeth(StringRef, SMLoc) {
334     return parseSectionSwitch("__OBJC", "__cat_cls_meth",
335                               MachO::S_ATTR_NO_DEAD_STRIP);
336   }
337 
338   bool parseSectionDirectiveObjCCatInstMeth(StringRef, SMLoc) {
339     return parseSectionSwitch("__OBJC", "__cat_inst_meth",
340                               MachO::S_ATTR_NO_DEAD_STRIP);
341   }
342 
343   bool parseSectionDirectiveObjCProtocol(StringRef, SMLoc) {
344     return parseSectionSwitch("__OBJC", "__protocol",
345                               MachO::S_ATTR_NO_DEAD_STRIP);
346   }
347 
348   bool parseSectionDirectiveObjCStringObject(StringRef, SMLoc) {
349     return parseSectionSwitch("__OBJC", "__string_object",
350                               MachO::S_ATTR_NO_DEAD_STRIP);
351   }
352 
353   bool parseSectionDirectiveObjCClsMeth(StringRef, SMLoc) {
354     return parseSectionSwitch("__OBJC", "__cls_meth",
355                               MachO::S_ATTR_NO_DEAD_STRIP);
356   }
357 
358   bool parseSectionDirectiveObjCInstMeth(StringRef, SMLoc) {
359     return parseSectionSwitch("__OBJC", "__inst_meth",
360                               MachO::S_ATTR_NO_DEAD_STRIP);
361   }
362 
363   bool parseSectionDirectiveObjCClsRefs(StringRef, SMLoc) {
364     return parseSectionSwitch("__OBJC", "__cls_refs",
365                               MachO::S_ATTR_NO_DEAD_STRIP |
366                               MachO::S_LITERAL_POINTERS, 4);
367   }
368 
369   bool parseSectionDirectiveObjCMessageRefs(StringRef, SMLoc) {
370     return parseSectionSwitch("__OBJC", "__message_refs",
371                               MachO::S_ATTR_NO_DEAD_STRIP |
372                               MachO::S_LITERAL_POINTERS, 4);
373   }
374 
375   bool parseSectionDirectiveObjCSymbols(StringRef, SMLoc) {
376     return parseSectionSwitch("__OBJC", "__symbols",
377                               MachO::S_ATTR_NO_DEAD_STRIP);
378   }
379 
380   bool parseSectionDirectiveObjCCategory(StringRef, SMLoc) {
381     return parseSectionSwitch("__OBJC", "__category",
382                               MachO::S_ATTR_NO_DEAD_STRIP);
383   }
384 
385   bool parseSectionDirectiveObjCClassVars(StringRef, SMLoc) {
386     return parseSectionSwitch("__OBJC", "__class_vars",
387                               MachO::S_ATTR_NO_DEAD_STRIP);
388   }
389 
390   bool parseSectionDirectiveObjCInstanceVars(StringRef, SMLoc) {
391     return parseSectionSwitch("__OBJC", "__instance_vars",
392                               MachO::S_ATTR_NO_DEAD_STRIP);
393   }
394 
395   bool parseSectionDirectiveObjCModuleInfo(StringRef, SMLoc) {
396     return parseSectionSwitch("__OBJC", "__module_info",
397                               MachO::S_ATTR_NO_DEAD_STRIP);
398   }
399 
400   bool parseSectionDirectiveObjCClassNames(StringRef, SMLoc) {
401     return parseSectionSwitch("__TEXT", "__cstring",
402                               MachO::S_CSTRING_LITERALS);
403   }
404 
405   bool parseSectionDirectiveObjCMethVarTypes(StringRef, SMLoc) {
406     return parseSectionSwitch("__TEXT", "__cstring",
407                               MachO::S_CSTRING_LITERALS);
408   }
409 
410   bool parseSectionDirectiveObjCMethVarNames(StringRef, SMLoc) {
411     return parseSectionSwitch("__TEXT", "__cstring",
412                               MachO::S_CSTRING_LITERALS);
413   }
414 
415   bool parseSectionDirectiveObjCSelectorStrs(StringRef, SMLoc) {
416     return parseSectionSwitch("__OBJC", "__selector_strs",
417                               MachO::S_CSTRING_LITERALS);
418   }
419 
420   bool parseSectionDirectiveTData(StringRef, SMLoc) {
421     return parseSectionSwitch("__DATA", "__thread_data",
422                               MachO::S_THREAD_LOCAL_REGULAR);
423   }
424 
425   bool parseSectionDirectiveText(StringRef, SMLoc) {
426     return parseSectionSwitch("__TEXT", "__text",
427                               MachO::S_ATTR_PURE_INSTRUCTIONS);
428   }
429 
430   bool parseSectionDirectiveTLV(StringRef, SMLoc) {
431     return parseSectionSwitch("__DATA", "__thread_vars",
432                               MachO::S_THREAD_LOCAL_VARIABLES);
433   }
434 
435   bool parseSectionDirectiveIdent(StringRef, SMLoc) {
436     // Darwin silently ignores the .ident directive.
437     getParser().eatToEndOfStatement();
438     return false;
439   }
440 
441   bool parseSectionDirectiveThreadInitFunc(StringRef, SMLoc) {
442     return parseSectionSwitch("__DATA", "__thread_init",
443                          MachO::S_THREAD_LOCAL_INIT_FUNCTION_POINTERS);
444   }
445 
446   bool parseWatchOSVersionMin(StringRef Directive, SMLoc Loc) {
447     return parseVersionMin(Directive, Loc, MCVM_WatchOSVersionMin);
448   }
449   bool parseTvOSVersionMin(StringRef Directive, SMLoc Loc) {
450     return parseVersionMin(Directive, Loc, MCVM_TvOSVersionMin);
451   }
452   bool parseIOSVersionMin(StringRef Directive, SMLoc Loc) {
453     return parseVersionMin(Directive, Loc, MCVM_IOSVersionMin);
454   }
455   bool parseMacOSXVersionMin(StringRef Directive, SMLoc Loc) {
456     return parseVersionMin(Directive, Loc, MCVM_OSXVersionMin);
457   }
458 
459   bool parseBuildVersion(StringRef Directive, SMLoc Loc);
460   bool parseVersionMin(StringRef Directive, SMLoc Loc, MCVersionMinType Type);
461   bool parseMajorMinorVersionComponent(unsigned *Major, unsigned *Minor,
462                                        const char *VersionName);
463   bool parseOptionalTrailingVersionComponent(unsigned *Component,
464                                              const char *ComponentName);
465   bool parseVersion(unsigned *Major, unsigned *Minor, unsigned *Update);
466   bool parseSDKVersion(VersionTuple &SDKVersion);
467   void checkVersion(StringRef Directive, StringRef Arg, SMLoc Loc,
468                     Triple::OSType ExpectedOS);
469   bool parseDirectiveCGProfile(StringRef Directive, SMLoc Loc);
470 };
471 
472 } // end anonymous namespace
473 
474 bool DarwinAsmParser::parseSectionSwitch(StringRef Segment, StringRef Section,
475                                          unsigned TAA, unsigned Alignment,
476                                          unsigned StubSize) {
477   if (getLexer().isNot(AsmToken::EndOfStatement))
478     return TokError("unexpected token in section switching directive");
479   Lex();
480 
481   // FIXME: Arch specific.
482   bool isText = TAA & MachO::S_ATTR_PURE_INSTRUCTIONS;
483   getStreamer().switchSection(getContext().getMachOSection(
484       Segment, Section, TAA, StubSize,
485       isText ? SectionKind::getText() : SectionKind::getData()));
486 
487   // Set the implicit alignment, if any.
488   //
489   // FIXME: This isn't really what 'as' does; I think it just uses the implicit
490   // alignment on the section (e.g., if one manually inserts bytes into the
491   // section, then just issuing the section switch directive will not realign
492   // the section. However, this is arguably more reasonable behavior, and there
493   // is no good reason for someone to intentionally emit incorrectly sized
494   // values into the implicitly aligned sections.
495   if (Alignment)
496     getStreamer().emitValueToAlignment(Align(Alignment));
497 
498   return false;
499 }
500 
501 /// parseDirectiveAltEntry
502 ///  ::= .alt_entry identifier
503 bool DarwinAsmParser::parseDirectiveAltEntry(StringRef, SMLoc) {
504   StringRef Name;
505   if (getParser().parseIdentifier(Name))
506     return TokError("expected identifier in directive");
507 
508   // Look up symbol.
509   MCSymbol *Sym = getContext().getOrCreateSymbol(Name);
510 
511   if (Sym->isDefined())
512     return TokError(".alt_entry must preceed symbol definition");
513 
514   if (!getStreamer().emitSymbolAttribute(Sym, MCSA_AltEntry))
515     return TokError("unable to emit symbol attribute");
516 
517   Lex();
518   return false;
519 }
520 
521 /// parseDirectiveDesc
522 ///  ::= .desc identifier , expression
523 bool DarwinAsmParser::parseDirectiveDesc(StringRef, SMLoc) {
524   StringRef Name;
525   if (getParser().parseIdentifier(Name))
526     return TokError("expected identifier in directive");
527 
528   // Handle the identifier as the key symbol.
529   MCSymbol *Sym = getContext().getOrCreateSymbol(Name);
530 
531   if (getLexer().isNot(AsmToken::Comma))
532     return TokError("unexpected token in '.desc' directive");
533   Lex();
534 
535   int64_t DescValue;
536   if (getParser().parseAbsoluteExpression(DescValue))
537     return true;
538 
539   if (getLexer().isNot(AsmToken::EndOfStatement))
540     return TokError("unexpected token in '.desc' directive");
541 
542   Lex();
543 
544   // Set the n_desc field of this Symbol to this DescValue
545   getStreamer().emitSymbolDesc(Sym, DescValue);
546 
547   return false;
548 }
549 
550 /// parseDirectiveIndirectSymbol
551 ///  ::= .indirect_symbol identifier
552 bool DarwinAsmParser::parseDirectiveIndirectSymbol(StringRef, SMLoc Loc) {
553   const MCSectionMachO *Current = static_cast<const MCSectionMachO *>(
554       getStreamer().getCurrentSectionOnly());
555   MachO::SectionType SectionType = Current->getType();
556   if (SectionType != MachO::S_NON_LAZY_SYMBOL_POINTERS &&
557       SectionType != MachO::S_LAZY_SYMBOL_POINTERS &&
558       SectionType != MachO::S_THREAD_LOCAL_VARIABLE_POINTERS &&
559       SectionType != MachO::S_SYMBOL_STUBS)
560     return Error(Loc, "indirect symbol not in a symbol pointer or stub "
561                       "section");
562 
563   StringRef Name;
564   if (getParser().parseIdentifier(Name))
565     return TokError("expected identifier in .indirect_symbol directive");
566 
567   MCSymbol *Sym = getContext().getOrCreateSymbol(Name);
568 
569   // Assembler local symbols don't make any sense here. Complain loudly.
570   if (Sym->isTemporary())
571     return TokError("non-local symbol required in directive");
572 
573   if (!getStreamer().emitSymbolAttribute(Sym, MCSA_IndirectSymbol))
574     return TokError("unable to emit indirect symbol attribute for: " + Name);
575 
576   if (getLexer().isNot(AsmToken::EndOfStatement))
577     return TokError("unexpected token in '.indirect_symbol' directive");
578 
579   Lex();
580 
581   return false;
582 }
583 
584 /// parseDirectiveDumpOrLoad
585 ///  ::= ( .dump | .load ) "filename"
586 bool DarwinAsmParser::parseDirectiveDumpOrLoad(StringRef Directive,
587                                                SMLoc IDLoc) {
588   bool IsDump = Directive == ".dump";
589   if (getLexer().isNot(AsmToken::String))
590     return TokError("expected string in '.dump' or '.load' directive");
591 
592   Lex();
593 
594   if (getLexer().isNot(AsmToken::EndOfStatement))
595     return TokError("unexpected token in '.dump' or '.load' directive");
596 
597   Lex();
598 
599   // FIXME: If/when .dump and .load are implemented they will be done in the
600   // the assembly parser and not have any need for an MCStreamer API.
601   if (IsDump)
602     return Warning(IDLoc, "ignoring directive .dump for now");
603   else
604     return Warning(IDLoc, "ignoring directive .load for now");
605 }
606 
607 /// ParseDirectiveLinkerOption
608 ///  ::= .linker_option "string" ( , "string" )*
609 bool DarwinAsmParser::parseDirectiveLinkerOption(StringRef IDVal, SMLoc) {
610   SmallVector<std::string, 4> Args;
611   while (true) {
612     if (getLexer().isNot(AsmToken::String))
613       return TokError("expected string in '" + Twine(IDVal) + "' directive");
614 
615     std::string Data;
616     if (getParser().parseEscapedString(Data))
617       return true;
618 
619     Args.push_back(Data);
620 
621     if (getLexer().is(AsmToken::EndOfStatement))
622       break;
623 
624     if (getLexer().isNot(AsmToken::Comma))
625       return TokError("unexpected token in '" + Twine(IDVal) + "' directive");
626     Lex();
627   }
628 
629   getStreamer().emitLinkerOptions(Args);
630   return false;
631 }
632 
633 /// parseDirectiveLsym
634 ///  ::= .lsym identifier , expression
635 bool DarwinAsmParser::parseDirectiveLsym(StringRef, SMLoc) {
636   StringRef Name;
637   if (getParser().parseIdentifier(Name))
638     return TokError("expected identifier in directive");
639 
640   // Handle the identifier as the key symbol.
641   MCSymbol *Sym = getContext().getOrCreateSymbol(Name);
642 
643   if (getLexer().isNot(AsmToken::Comma))
644     return TokError("unexpected token in '.lsym' directive");
645   Lex();
646 
647   const MCExpr *Value;
648   if (getParser().parseExpression(Value))
649     return true;
650 
651   if (getLexer().isNot(AsmToken::EndOfStatement))
652     return TokError("unexpected token in '.lsym' directive");
653 
654   Lex();
655 
656   // We don't currently support this directive.
657   //
658   // FIXME: Diagnostic location!
659   (void) Sym;
660   return TokError("directive '.lsym' is unsupported");
661 }
662 
663 /// parseDirectiveSection:
664 ///   ::= .section identifier (',' identifier)*
665 bool DarwinAsmParser::parseDirectiveSection(StringRef, SMLoc) {
666   SMLoc Loc = getLexer().getLoc();
667 
668   StringRef SectionName;
669   if (getParser().parseIdentifier(SectionName))
670     return Error(Loc, "expected identifier after '.section' directive");
671 
672   // Verify there is a following comma.
673   if (!getLexer().is(AsmToken::Comma))
674     return TokError("unexpected token in '.section' directive");
675 
676   std::string SectionSpec = std::string(SectionName);
677   SectionSpec += ",";
678 
679   // Add all the tokens until the end of the line, ParseSectionSpecifier will
680   // handle this.
681   StringRef EOL = getLexer().LexUntilEndOfStatement();
682   SectionSpec.append(EOL.begin(), EOL.end());
683 
684   Lex();
685   if (getLexer().isNot(AsmToken::EndOfStatement))
686     return TokError("unexpected token in '.section' directive");
687   Lex();
688 
689   StringRef Segment, Section;
690   unsigned StubSize;
691   unsigned TAA;
692   bool TAAParsed;
693   if (class Error E = MCSectionMachO::ParseSectionSpecifier(
694           SectionSpec, Segment, Section, TAA, TAAParsed, StubSize))
695     return Error(Loc, toString(std::move(E)));
696 
697   // Issue a warning if the target is not powerpc and Section is a *coal* section.
698   Triple TT = getParser().getContext().getTargetTriple();
699   Triple::ArchType ArchTy = TT.getArch();
700 
701   if (ArchTy != Triple::ppc && ArchTy != Triple::ppc64) {
702     StringRef NonCoalSection = StringSwitch<StringRef>(Section)
703                                    .Case("__textcoal_nt", "__text")
704                                    .Case("__const_coal", "__const")
705                                    .Case("__datacoal_nt", "__data")
706                                    .Default(Section);
707 
708     if (!Section.equals(NonCoalSection)) {
709       StringRef SectionVal(Loc.getPointer());
710       size_t B = SectionVal.find(',') + 1, E = SectionVal.find(',', B);
711       SMLoc BLoc = SMLoc::getFromPointer(SectionVal.data() + B);
712       SMLoc ELoc = SMLoc::getFromPointer(SectionVal.data() + E);
713       getParser().Warning(Loc, "section \"" + Section + "\" is deprecated",
714                           SMRange(BLoc, ELoc));
715       getParser().Note(Loc, "change section name to \"" + NonCoalSection +
716                        "\"", SMRange(BLoc, ELoc));
717     }
718   }
719 
720   // FIXME: Arch specific.
721   bool isText = Segment == "__TEXT";  // FIXME: Hack.
722   getStreamer().switchSection(getContext().getMachOSection(
723       Segment, Section, TAA, StubSize,
724       isText ? SectionKind::getText() : SectionKind::getData()));
725   return false;
726 }
727 
728 /// ParseDirectivePushSection:
729 ///   ::= .pushsection identifier (',' identifier)*
730 bool DarwinAsmParser::parseDirectivePushSection(StringRef S, SMLoc Loc) {
731   getStreamer().pushSection();
732 
733   if (parseDirectiveSection(S, Loc)) {
734     getStreamer().popSection();
735     return true;
736   }
737 
738   return false;
739 }
740 
741 /// ParseDirectivePopSection:
742 ///   ::= .popsection
743 bool DarwinAsmParser::parseDirectivePopSection(StringRef, SMLoc) {
744   if (!getStreamer().popSection())
745     return TokError(".popsection without corresponding .pushsection");
746   return false;
747 }
748 
749 /// ParseDirectivePrevious:
750 ///   ::= .previous
751 bool DarwinAsmParser::parseDirectivePrevious(StringRef DirName, SMLoc) {
752   MCSectionSubPair PreviousSection = getStreamer().getPreviousSection();
753   if (!PreviousSection.first)
754     return TokError(".previous without corresponding .section");
755   getStreamer().switchSection(PreviousSection.first, PreviousSection.second);
756   return false;
757 }
758 
759 /// ParseDirectiveSecureLogUnique
760 ///  ::= .secure_log_unique ... message ...
761 bool DarwinAsmParser::parseDirectiveSecureLogUnique(StringRef, SMLoc IDLoc) {
762   StringRef LogMessage = getParser().parseStringToEndOfStatement();
763   if (getLexer().isNot(AsmToken::EndOfStatement))
764     return TokError("unexpected token in '.secure_log_unique' directive");
765 
766   if (getContext().getSecureLogUsed())
767     return Error(IDLoc, ".secure_log_unique specified multiple times");
768 
769   // Get the secure log path.
770   StringRef SecureLogFile = getContext().getSecureLogFile();
771   if (SecureLogFile.empty())
772     return Error(IDLoc, ".secure_log_unique used but AS_SECURE_LOG_FILE "
773                  "environment variable unset.");
774 
775   // Open the secure log file if we haven't already.
776   raw_fd_ostream *OS = getContext().getSecureLog();
777   if (!OS) {
778     std::error_code EC;
779     auto NewOS = std::make_unique<raw_fd_ostream>(
780         SecureLogFile, EC, sys::fs::OF_Append | sys::fs::OF_TextWithCRLF);
781     if (EC)
782        return Error(IDLoc, Twine("can't open secure log file: ") +
783                                SecureLogFile + " (" + EC.message() + ")");
784     OS = NewOS.get();
785     getContext().setSecureLog(std::move(NewOS));
786   }
787 
788   // Write the message.
789   unsigned CurBuf = getSourceManager().FindBufferContainingLoc(IDLoc);
790   *OS << getSourceManager().getBufferInfo(CurBuf).Buffer->getBufferIdentifier()
791       << ":" << getSourceManager().FindLineNumber(IDLoc, CurBuf) << ":"
792       << LogMessage + "\n";
793 
794   getContext().setSecureLogUsed(true);
795 
796   return false;
797 }
798 
799 /// ParseDirectiveSecureLogReset
800 ///  ::= .secure_log_reset
801 bool DarwinAsmParser::parseDirectiveSecureLogReset(StringRef, SMLoc IDLoc) {
802   if (getLexer().isNot(AsmToken::EndOfStatement))
803     return TokError("unexpected token in '.secure_log_reset' directive");
804 
805   Lex();
806 
807   getContext().setSecureLogUsed(false);
808 
809   return false;
810 }
811 
812 /// parseDirectiveSubsectionsViaSymbols
813 ///  ::= .subsections_via_symbols
814 bool DarwinAsmParser::parseDirectiveSubsectionsViaSymbols(StringRef, SMLoc) {
815   if (getLexer().isNot(AsmToken::EndOfStatement))
816     return TokError("unexpected token in '.subsections_via_symbols' directive");
817 
818   Lex();
819 
820   getStreamer().emitAssemblerFlag(MCAF_SubsectionsViaSymbols);
821 
822   return false;
823 }
824 
825 /// ParseDirectiveTBSS
826 ///  ::= .tbss identifier, size, align
827 bool DarwinAsmParser::parseDirectiveTBSS(StringRef, SMLoc) {
828   SMLoc IDLoc = getLexer().getLoc();
829   StringRef Name;
830   if (getParser().parseIdentifier(Name))
831     return TokError("expected identifier in directive");
832 
833   // Handle the identifier as the key symbol.
834   MCSymbol *Sym = getContext().getOrCreateSymbol(Name);
835 
836   if (getLexer().isNot(AsmToken::Comma))
837     return TokError("unexpected token in directive");
838   Lex();
839 
840   int64_t Size;
841   SMLoc SizeLoc = getLexer().getLoc();
842   if (getParser().parseAbsoluteExpression(Size))
843     return true;
844 
845   int64_t Pow2Alignment = 0;
846   SMLoc Pow2AlignmentLoc;
847   if (getLexer().is(AsmToken::Comma)) {
848     Lex();
849     Pow2AlignmentLoc = getLexer().getLoc();
850     if (getParser().parseAbsoluteExpression(Pow2Alignment))
851       return true;
852   }
853 
854   if (getLexer().isNot(AsmToken::EndOfStatement))
855     return TokError("unexpected token in '.tbss' directive");
856 
857   Lex();
858 
859   if (Size < 0)
860     return Error(SizeLoc, "invalid '.tbss' directive size, can't be less than"
861                  "zero");
862 
863   // FIXME: Diagnose overflow.
864   if (Pow2Alignment < 0)
865     return Error(Pow2AlignmentLoc, "invalid '.tbss' alignment, can't be less"
866                  "than zero");
867 
868   if (!Sym->isUndefined())
869     return Error(IDLoc, "invalid symbol redefinition");
870 
871   getStreamer().emitTBSSSymbol(
872       getContext().getMachOSection("__DATA", "__thread_bss",
873                                    MachO::S_THREAD_LOCAL_ZEROFILL, 0,
874                                    SectionKind::getThreadBSS()),
875       Sym, Size, Align(1ULL << Pow2Alignment));
876 
877   return false;
878 }
879 
880 /// ParseDirectiveZerofill
881 ///  ::= .zerofill segname , sectname [, identifier , size_expression [
882 ///      , align_expression ]]
883 bool DarwinAsmParser::parseDirectiveZerofill(StringRef, SMLoc) {
884   StringRef Segment;
885   if (getParser().parseIdentifier(Segment))
886     return TokError("expected segment name after '.zerofill' directive");
887 
888   if (getLexer().isNot(AsmToken::Comma))
889     return TokError("unexpected token in directive");
890   Lex();
891 
892   StringRef Section;
893   SMLoc SectionLoc = getLexer().getLoc();
894   if (getParser().parseIdentifier(Section))
895     return TokError("expected section name after comma in '.zerofill' "
896                     "directive");
897 
898   // If this is the end of the line all that was wanted was to create the
899   // the section but with no symbol.
900   if (getLexer().is(AsmToken::EndOfStatement)) {
901     // Create the zerofill section but no symbol
902     getStreamer().emitZerofill(
903         getContext().getMachOSection(Segment, Section, MachO::S_ZEROFILL, 0,
904                                      SectionKind::getBSS()),
905         /*Symbol=*/nullptr, /*Size=*/0, Align(1), SectionLoc);
906     return false;
907   }
908 
909   if (getLexer().isNot(AsmToken::Comma))
910     return TokError("unexpected token in directive");
911   Lex();
912 
913   SMLoc IDLoc = getLexer().getLoc();
914   StringRef IDStr;
915   if (getParser().parseIdentifier(IDStr))
916     return TokError("expected identifier in directive");
917 
918   // handle the identifier as the key symbol.
919   MCSymbol *Sym = getContext().getOrCreateSymbol(IDStr);
920 
921   if (getLexer().isNot(AsmToken::Comma))
922     return TokError("unexpected token in directive");
923   Lex();
924 
925   int64_t Size;
926   SMLoc SizeLoc = getLexer().getLoc();
927   if (getParser().parseAbsoluteExpression(Size))
928     return true;
929 
930   int64_t Pow2Alignment = 0;
931   SMLoc Pow2AlignmentLoc;
932   if (getLexer().is(AsmToken::Comma)) {
933     Lex();
934     Pow2AlignmentLoc = getLexer().getLoc();
935     if (getParser().parseAbsoluteExpression(Pow2Alignment))
936       return true;
937   }
938 
939   if (getLexer().isNot(AsmToken::EndOfStatement))
940     return TokError("unexpected token in '.zerofill' directive");
941 
942   Lex();
943 
944   if (Size < 0)
945     return Error(SizeLoc, "invalid '.zerofill' directive size, can't be less "
946                  "than zero");
947 
948   // NOTE: The alignment in the directive is a power of 2 value, the assembler
949   // may internally end up wanting an alignment in bytes.
950   // FIXME: Diagnose overflow.
951   if (Pow2Alignment < 0)
952     return Error(Pow2AlignmentLoc, "invalid '.zerofill' directive alignment, "
953                  "can't be less than zero");
954 
955   if (!Sym->isUndefined())
956     return Error(IDLoc, "invalid symbol redefinition");
957 
958   // Create the zerofill Symbol with Size and Pow2Alignment
959   //
960   // FIXME: Arch specific.
961   getStreamer().emitZerofill(
962       getContext().getMachOSection(Segment, Section, MachO::S_ZEROFILL, 0,
963                                    SectionKind::getBSS()),
964       Sym, Size, Align(1ULL << Pow2Alignment), SectionLoc);
965 
966   return false;
967 }
968 
969 /// ParseDirectiveDataRegion
970 ///  ::= .data_region [ ( jt8 | jt16 | jt32 ) ]
971 bool DarwinAsmParser::parseDirectiveDataRegion(StringRef, SMLoc) {
972   if (getLexer().is(AsmToken::EndOfStatement)) {
973     Lex();
974     getStreamer().emitDataRegion(MCDR_DataRegion);
975     return false;
976   }
977   StringRef RegionType;
978   SMLoc Loc = getParser().getTok().getLoc();
979   if (getParser().parseIdentifier(RegionType))
980     return TokError("expected region type after '.data_region' directive");
981   int Kind = StringSwitch<int>(RegionType)
982     .Case("jt8", MCDR_DataRegionJT8)
983     .Case("jt16", MCDR_DataRegionJT16)
984     .Case("jt32", MCDR_DataRegionJT32)
985     .Default(-1);
986   if (Kind == -1)
987     return Error(Loc, "unknown region type in '.data_region' directive");
988   Lex();
989 
990   getStreamer().emitDataRegion((MCDataRegionType)Kind);
991   return false;
992 }
993 
994 /// ParseDirectiveDataRegionEnd
995 ///  ::= .end_data_region
996 bool DarwinAsmParser::parseDirectiveDataRegionEnd(StringRef, SMLoc) {
997   if (getLexer().isNot(AsmToken::EndOfStatement))
998     return TokError("unexpected token in '.end_data_region' directive");
999 
1000   Lex();
1001   getStreamer().emitDataRegion(MCDR_DataRegionEnd);
1002   return false;
1003 }
1004 
1005 static bool isSDKVersionToken(const AsmToken &Tok) {
1006   return Tok.is(AsmToken::Identifier) && Tok.getIdentifier() == "sdk_version";
1007 }
1008 
1009 /// parseMajorMinorVersionComponent ::= major, minor
1010 bool DarwinAsmParser::parseMajorMinorVersionComponent(unsigned *Major,
1011                                                       unsigned *Minor,
1012                                                       const char *VersionName) {
1013   // Get the major version number.
1014   if (getLexer().isNot(AsmToken::Integer))
1015     return TokError(Twine("invalid ") + VersionName +
1016                     " major version number, integer expected");
1017   int64_t MajorVal = getLexer().getTok().getIntVal();
1018   if (MajorVal > 65535 || MajorVal <= 0)
1019     return TokError(Twine("invalid ") + VersionName + " major version number");
1020   *Major = (unsigned)MajorVal;
1021   Lex();
1022   if (getLexer().isNot(AsmToken::Comma))
1023     return TokError(Twine(VersionName) +
1024                     " minor version number required, comma expected");
1025   Lex();
1026   // Get the minor version number.
1027   if (getLexer().isNot(AsmToken::Integer))
1028     return TokError(Twine("invalid ") + VersionName +
1029                     " minor version number, integer expected");
1030   int64_t MinorVal = getLexer().getTok().getIntVal();
1031   if (MinorVal > 255 || MinorVal < 0)
1032     return TokError(Twine("invalid ") + VersionName + " minor version number");
1033   *Minor = MinorVal;
1034   Lex();
1035   return false;
1036 }
1037 
1038 /// parseOptionalTrailingVersionComponent ::= , version_number
1039 bool DarwinAsmParser::parseOptionalTrailingVersionComponent(
1040     unsigned *Component, const char *ComponentName) {
1041   assert(getLexer().is(AsmToken::Comma) && "comma expected");
1042   Lex();
1043   if (getLexer().isNot(AsmToken::Integer))
1044     return TokError(Twine("invalid ") + ComponentName +
1045                     " version number, integer expected");
1046   int64_t Val = getLexer().getTok().getIntVal();
1047   if (Val > 255 || Val < 0)
1048     return TokError(Twine("invalid ") + ComponentName + " version number");
1049   *Component = Val;
1050   Lex();
1051   return false;
1052 }
1053 
1054 /// parseVersion ::= parseMajorMinorVersionComponent
1055 ///                      parseOptionalTrailingVersionComponent
1056 bool DarwinAsmParser::parseVersion(unsigned *Major, unsigned *Minor,
1057                                    unsigned *Update) {
1058   if (parseMajorMinorVersionComponent(Major, Minor, "OS"))
1059     return true;
1060 
1061   // Get the update level, if specified
1062   *Update = 0;
1063   if (getLexer().is(AsmToken::EndOfStatement) ||
1064       isSDKVersionToken(getLexer().getTok()))
1065     return false;
1066   if (getLexer().isNot(AsmToken::Comma))
1067     return TokError("invalid OS update specifier, comma expected");
1068   if (parseOptionalTrailingVersionComponent(Update, "OS update"))
1069     return true;
1070   return false;
1071 }
1072 
1073 bool DarwinAsmParser::parseSDKVersion(VersionTuple &SDKVersion) {
1074   assert(isSDKVersionToken(getLexer().getTok()) && "expected sdk_version");
1075   Lex();
1076   unsigned Major, Minor;
1077   if (parseMajorMinorVersionComponent(&Major, &Minor, "SDK"))
1078     return true;
1079   SDKVersion = VersionTuple(Major, Minor);
1080 
1081   // Get the subminor version, if specified.
1082   if (getLexer().is(AsmToken::Comma)) {
1083     unsigned Subminor;
1084     if (parseOptionalTrailingVersionComponent(&Subminor, "SDK subminor"))
1085       return true;
1086     SDKVersion = VersionTuple(Major, Minor, Subminor);
1087   }
1088   return false;
1089 }
1090 
1091 void DarwinAsmParser::checkVersion(StringRef Directive, StringRef Arg,
1092                                    SMLoc Loc, Triple::OSType ExpectedOS) {
1093   const Triple &Target = getContext().getTargetTriple();
1094   if (Target.getOS() != ExpectedOS)
1095     Warning(Loc, Twine(Directive) +
1096             (Arg.empty() ? Twine() : Twine(' ') + Arg) +
1097             " used while targeting " + Target.getOSName());
1098 
1099   if (LastVersionDirective.isValid()) {
1100     Warning(Loc, "overriding previous version directive");
1101     Note(LastVersionDirective, "previous definition is here");
1102   }
1103   LastVersionDirective = Loc;
1104 }
1105 
1106 static Triple::OSType getOSTypeFromMCVM(MCVersionMinType Type) {
1107   switch (Type) {
1108   case MCVM_WatchOSVersionMin: return Triple::WatchOS;
1109   case MCVM_TvOSVersionMin:    return Triple::TvOS;
1110   case MCVM_IOSVersionMin:     return Triple::IOS;
1111   case MCVM_OSXVersionMin:     return Triple::MacOSX;
1112   }
1113   llvm_unreachable("Invalid mc version min type");
1114 }
1115 
1116 /// parseVersionMin
1117 ///   ::= .ios_version_min parseVersion parseSDKVersion
1118 ///   |   .macosx_version_min parseVersion parseSDKVersion
1119 ///   |   .tvos_version_min parseVersion parseSDKVersion
1120 ///   |   .watchos_version_min parseVersion parseSDKVersion
1121 bool DarwinAsmParser::parseVersionMin(StringRef Directive, SMLoc Loc,
1122                                       MCVersionMinType Type) {
1123   unsigned Major;
1124   unsigned Minor;
1125   unsigned Update;
1126   if (parseVersion(&Major, &Minor, &Update))
1127     return true;
1128 
1129   VersionTuple SDKVersion;
1130   if (isSDKVersionToken(getLexer().getTok()) && parseSDKVersion(SDKVersion))
1131     return true;
1132 
1133   if (parseToken(AsmToken::EndOfStatement))
1134     return addErrorSuffix(Twine(" in '") + Directive + "' directive");
1135 
1136   Triple::OSType ExpectedOS = getOSTypeFromMCVM(Type);
1137   checkVersion(Directive, StringRef(), Loc, ExpectedOS);
1138   getStreamer().emitVersionMin(Type, Major, Minor, Update, SDKVersion);
1139   return false;
1140 }
1141 
1142 static Triple::OSType getOSTypeFromPlatform(MachO::PlatformType Type) {
1143   switch (Type) {
1144   case MachO::PLATFORM_UNKNOWN: /* silence warning */
1145     break;
1146   case MachO::PLATFORM_MACOS:   return Triple::MacOSX;
1147   case MachO::PLATFORM_IOS:     return Triple::IOS;
1148   case MachO::PLATFORM_TVOS:    return Triple::TvOS;
1149   case MachO::PLATFORM_WATCHOS: return Triple::WatchOS;
1150   case MachO::PLATFORM_BRIDGEOS:         /* silence warning */ break;
1151   case MachO::PLATFORM_DRIVERKIT:
1152     return Triple::DriverKit;
1153   case MachO::PLATFORM_MACCATALYST: return Triple::IOS;
1154   case MachO::PLATFORM_IOSSIMULATOR:     /* silence warning */ break;
1155   case MachO::PLATFORM_TVOSSIMULATOR:    /* silence warning */ break;
1156   case MachO::PLATFORM_WATCHOSSIMULATOR: /* silence warning */ break;
1157   }
1158   llvm_unreachable("Invalid mach-o platform type");
1159 }
1160 
1161 /// parseBuildVersion
1162 ///   ::= .build_version (macos|ios|tvos|watchos), parseVersion parseSDKVersion
1163 bool DarwinAsmParser::parseBuildVersion(StringRef Directive, SMLoc Loc) {
1164   StringRef PlatformName;
1165   SMLoc PlatformLoc = getTok().getLoc();
1166   if (getParser().parseIdentifier(PlatformName))
1167     return TokError("platform name expected");
1168 
1169   unsigned Platform = StringSwitch<unsigned>(PlatformName)
1170     .Case("macos", MachO::PLATFORM_MACOS)
1171     .Case("ios", MachO::PLATFORM_IOS)
1172     .Case("tvos", MachO::PLATFORM_TVOS)
1173     .Case("watchos", MachO::PLATFORM_WATCHOS)
1174     .Case("macCatalyst", MachO::PLATFORM_MACCATALYST)
1175     .Case("driverkit", MachO::PLATFORM_DRIVERKIT)
1176     .Default(0);
1177   if (Platform == 0)
1178     return Error(PlatformLoc, "unknown platform name");
1179 
1180   if (getLexer().isNot(AsmToken::Comma))
1181     return TokError("version number required, comma expected");
1182   Lex();
1183 
1184   unsigned Major;
1185   unsigned Minor;
1186   unsigned Update;
1187   if (parseVersion(&Major, &Minor, &Update))
1188     return true;
1189 
1190   VersionTuple SDKVersion;
1191   if (isSDKVersionToken(getLexer().getTok()) && parseSDKVersion(SDKVersion))
1192     return true;
1193 
1194   if (parseToken(AsmToken::EndOfStatement))
1195     return addErrorSuffix(" in '.build_version' directive");
1196 
1197   Triple::OSType ExpectedOS
1198     = getOSTypeFromPlatform((MachO::PlatformType)Platform);
1199   checkVersion(Directive, PlatformName, Loc, ExpectedOS);
1200   getStreamer().emitBuildVersion(Platform, Major, Minor, Update, SDKVersion);
1201   return false;
1202 }
1203 
1204 /// parseDirectiveCGProfile
1205 ///   ::= .cg_profile from, to, count
1206 bool DarwinAsmParser::parseDirectiveCGProfile(StringRef S, SMLoc Loc) {
1207   return MCAsmParserExtension::ParseDirectiveCGProfile(S, Loc);
1208 }
1209 
1210 namespace llvm {
1211 
1212 MCAsmParserExtension *createDarwinAsmParser() {
1213   return new DarwinAsmParser;
1214 }
1215 
1216 } // end llvm namespace
1217