1//===- AsmParser.cpp - Parser for Assembly Files --------------------------===//
2//
3// The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This class implements the parser for assembly files.
11//
12//===----------------------------------------------------------------------===//
13
14#include "llvm/MC/MCParser/AsmParser.h"
15#include "llvm/ADT/SmallString.h"
16#include "llvm/ADT/Twine.h"
17#include "llvm/MC/MCContext.h"
18#include "llvm/MC/MCExpr.h"
19#include "llvm/MC/MCInst.h"
20#include "llvm/MC/MCSectionMachO.h"
21#include "llvm/MC/MCStreamer.h"
22#include "llvm/MC/MCSymbol.h"
23#include "llvm/MC/MCParser/MCParsedAsmOperand.h"
24#include "llvm/Support/Compiler.h"
25#include "llvm/Support/SourceMgr.h"
26#include "llvm/Support/raw_ostream.h"
27#include "llvm/Target/TargetAsmParser.h"
28using namespace llvm;
29
30
31enum { DEFAULT_ADDRSPACE = 0 };
32
33// Mach-O section uniquing.
34//
35// FIXME: Figure out where this should live, it should be shared by
36// TargetLoweringObjectFile.
37typedef StringMap<const MCSectionMachO*> MachOUniqueMapTy;
38
39AsmParser::AsmParser(SourceMgr &_SM, MCContext &_Ctx, MCStreamer &_Out,
40 const MCAsmInfo &_MAI)
41 : Lexer(_MAI), Ctx(_Ctx), Out(_Out), SrcMgr(_SM), TargetParser(0),
42 CurBuffer(0), SectionUniquingMap(0) {
43 Lexer.setBuffer(SrcMgr.getMemoryBuffer(CurBuffer));
44
45 // Debugging directives.
46 AddDirectiveHandler(".file", &AsmParser::ParseDirectiveFile);
47 AddDirectiveHandler(".line", &AsmParser::ParseDirectiveLine);
48 AddDirectiveHandler(".loc", &AsmParser::ParseDirectiveLoc);
49}
50
51
52
53AsmParser::~AsmParser() {
54 // If we have the MachO uniquing map, free it.
55 delete (MachOUniqueMapTy*)SectionUniquingMap;
56}
57
58const MCSection *AsmParser::getMachOSection(const StringRef &Segment,
59 const StringRef &Section,
60 unsigned TypeAndAttributes,
61 unsigned Reserved2,
62 SectionKind Kind) const {
63 // We unique sections by their segment/section pair. The returned section
64 // may not have the same flags as the requested section, if so this should be
65 // diagnosed by the client as an error.
66
67 // Create the map if it doesn't already exist.
68 if (SectionUniquingMap == 0)
69 SectionUniquingMap = new MachOUniqueMapTy();
70 MachOUniqueMapTy &Map = *(MachOUniqueMapTy*)SectionUniquingMap;
71
72 // Form the name to look up.
73 SmallString<64> Name;
74 Name += Segment;
75 Name.push_back(',');
76 Name += Section;
77
78 // Do the lookup, if we have a hit, return it.
79 const MCSectionMachO *&Entry = Map[Name.str()];
80
81 // FIXME: This should validate the type and attributes.
82 if (Entry) return Entry;
83
84 // Otherwise, return a new section.
85 return Entry = MCSectionMachO::Create(Segment, Section, TypeAndAttributes,
86 Reserved2, Kind, Ctx);
87}
88
89void AsmParser::Warning(SMLoc L, const Twine &Msg) {
90 PrintMessage(L, Msg.str(), "warning");
91}
92
93bool AsmParser::Error(SMLoc L, const Twine &Msg) {
94 PrintMessage(L, Msg.str(), "error");
95 return true;
96}
97
98bool AsmParser::TokError(const char *Msg) {
99 PrintMessage(Lexer.getLoc(), Msg, "error");
100 return true;
101}
102
103void AsmParser::PrintMessage(SMLoc Loc, const std::string &Msg,
104 const char *Type) const {
105 SrcMgr.PrintMessage(Loc, Msg, Type);
106}
107
108bool AsmParser::EnterIncludeFile(const std::string &Filename) {
109 int NewBuf = SrcMgr.AddIncludeFile(Filename, Lexer.getLoc());
110 if (NewBuf == -1)
111 return true;
112
113 CurBuffer = NewBuf;
114
115 Lexer.setBuffer(SrcMgr.getMemoryBuffer(CurBuffer));
116
117 return false;
118}
119
120const AsmToken &AsmParser::Lex() {
121 const AsmToken *tok = &Lexer.Lex();
122
123 if (tok->is(AsmToken::Eof)) {
124 // If this is the end of an included file, pop the parent file off the
125 // include stack.
126 SMLoc ParentIncludeLoc = SrcMgr.getParentIncludeLoc(CurBuffer);
127 if (ParentIncludeLoc != SMLoc()) {
128 CurBuffer = SrcMgr.FindBufferContainingLoc(ParentIncludeLoc);
129 Lexer.setBuffer(SrcMgr.getMemoryBuffer(CurBuffer),
130 ParentIncludeLoc.getPointer());
131 tok = &Lexer.Lex();
132 }
133 }
134
135 if (tok->is(AsmToken::Error))
136 PrintMessage(Lexer.getErrLoc(), Lexer.getErr(), "error");
137
138 return *tok;
139}
140
141bool AsmParser::Run(bool NoInitialTextSection) {
142 // Create the initial section, if requested.
143 //
144 // FIXME: Target hook & command line option for initial section.
145 if (!NoInitialTextSection)
146 Out.SwitchSection(getMachOSection("__TEXT", "__text",
147 MCSectionMachO::S_ATTR_PURE_INSTRUCTIONS,
148 0, SectionKind::getText()));
149
150 // Prime the lexer.
151 Lex();
152
153 bool HadError = false;
154
155 AsmCond StartingCondState = TheCondState;
156
157 // While we have input, parse each statement.
158 while (Lexer.isNot(AsmToken::Eof)) {
159 // Handle conditional assembly here before calling ParseStatement()
160 if (Lexer.getKind() == AsmToken::Identifier) {
161 // If we have an identifier, handle it as the key symbol.
162 AsmToken ID = getTok();
163 SMLoc IDLoc = ID.getLoc();
164 StringRef IDVal = ID.getString();
165
166 if (IDVal == ".if" ||
167 IDVal == ".elseif" ||
168 IDVal == ".else" ||
169 IDVal == ".endif") {
170 if (!ParseConditionalAssemblyDirectives(IDVal, IDLoc))
171 continue;
172 HadError = true;
173 EatToEndOfStatement();
174 continue;
175 }
176 }
177 if (TheCondState.Ignore) {
178 EatToEndOfStatement();
179 continue;
180 }
181
182 if (!ParseStatement()) continue;
183
184 // We had an error, remember it and recover by skipping to the next line.
185 HadError = true;
186 EatToEndOfStatement();
187 }
188
189 if (TheCondState.TheCond != StartingCondState.TheCond ||
190 TheCondState.Ignore != StartingCondState.Ignore)
191 return TokError("unmatched .ifs or .elses");
192
193 if (!HadError)
194 Out.Finish();
195
196 return HadError;
197}
198
199/// ParseConditionalAssemblyDirectives - parse the conditional assembly
200/// directives
201bool AsmParser::ParseConditionalAssemblyDirectives(StringRef Directive,
202 SMLoc DirectiveLoc) {
203 if (Directive == ".if")
204 return ParseDirectiveIf(DirectiveLoc);
205 if (Directive == ".elseif")
206 return ParseDirectiveElseIf(DirectiveLoc);
207 if (Directive == ".else")
208 return ParseDirectiveElse(DirectiveLoc);
209 if (Directive == ".endif")
210 return ParseDirectiveEndIf(DirectiveLoc);
211 return true;
212}
213
214/// EatToEndOfStatement - Throw away the rest of the line for testing purposes.
215void AsmParser::EatToEndOfStatement() {
216 while (Lexer.isNot(AsmToken::EndOfStatement) &&
217 Lexer.isNot(AsmToken::Eof))
218 Lex();
219
220 // Eat EOL.
221 if (Lexer.is(AsmToken::EndOfStatement))
222 Lex();
223}
224
225
226/// ParseParenExpr - Parse a paren expression and return it.
227/// NOTE: This assumes the leading '(' has already been consumed.
228///
229/// parenexpr ::= expr)
230///
231bool AsmParser::ParseParenExpr(const MCExpr *&Res, SMLoc &EndLoc) {
232 if (ParseExpression(Res)) return true;
233 if (Lexer.isNot(AsmToken::RParen))
234 return TokError("expected ')' in parentheses expression");
235 EndLoc = Lexer.getLoc();
236 Lex();
237 return false;
238}
239
240MCSymbol *AsmParser::CreateSymbol(StringRef Name) {
241 // If the label starts with L it is an assembler temporary label.
242 if (Name.startswith("L"))
243 return Ctx.GetOrCreateTemporarySymbol(Name);
244 return Ctx.GetOrCreateSymbol(Name);
245}
246
247/// ParsePrimaryExpr - Parse a primary expression and return it.
248/// primaryexpr ::= (parenexpr
249/// primaryexpr ::= symbol
250/// primaryexpr ::= number
251/// primaryexpr ::= ~,+,- primaryexpr
252bool AsmParser::ParsePrimaryExpr(const MCExpr *&Res, SMLoc &EndLoc) {
253 switch (Lexer.getKind()) {
254 default:
255 return TokError("unknown token in expression");
256 case AsmToken::Exclaim:
257 Lex(); // Eat the operator.
258 if (ParsePrimaryExpr(Res, EndLoc))
259 return true;
260 Res = MCUnaryExpr::CreateLNot(Res, getContext());
261 return false;
262 case AsmToken::String:
263 case AsmToken::Identifier: {
264 // This is a symbol reference.
265 std::pair<StringRef, StringRef> Split = getTok().getIdentifier().split('@');
266 MCSymbol *Sym = CreateSymbol(Split.first);
267
268 // Lookup the symbol variant if used.
269 MCSymbolRefExpr::VariantKind Variant = MCSymbolRefExpr::VK_None;
270 if (Split.first.size() != getTok().getIdentifier().size())
271 Variant = MCSymbolRefExpr::getVariantKindForName(Split.second);
272
273 EndLoc = Lexer.getLoc();
274 Lex(); // Eat identifier.
275
276 // If this is an absolute variable reference, substitute it now to preserve
277 // semantics in the face of reassignment.
278 if (Sym->getValue() && isa<MCConstantExpr>(Sym->getValue())) {
279 if (Variant)
280 return Error(EndLoc, "unexpected modified on variable reference");
281
282 Res = Sym->getValue();
283 return false;
284 }
285
286 // Otherwise create a symbol ref.
287 Res = MCSymbolRefExpr::Create(Sym, Variant, getContext());
288 return false;
289 }
290 case AsmToken::Integer:
291 Res = MCConstantExpr::Create(getTok().getIntVal(), getContext());
292 EndLoc = Lexer.getLoc();
293 Lex(); // Eat token.
294 return false;
295 case AsmToken::LParen:
296 Lex(); // Eat the '('.
297 return ParseParenExpr(Res, EndLoc);
298 case AsmToken::Minus:
299 Lex(); // Eat the operator.
300 if (ParsePrimaryExpr(Res, EndLoc))
301 return true;
302 Res = MCUnaryExpr::CreateMinus(Res, getContext());
303 return false;
304 case AsmToken::Plus:
305 Lex(); // Eat the operator.
306 if (ParsePrimaryExpr(Res, EndLoc))
307 return true;
308 Res = MCUnaryExpr::CreatePlus(Res, getContext());
309 return false;
310 case AsmToken::Tilde:
311 Lex(); // Eat the operator.
312 if (ParsePrimaryExpr(Res, EndLoc))
313 return true;
314 Res = MCUnaryExpr::CreateNot(Res, getContext());
315 return false;
316 }
317}
318
319bool AsmParser::ParseExpression(const MCExpr *&Res) {
320 SMLoc EndLoc;
321 return ParseExpression(Res, EndLoc);
322}
323
324/// ParseExpression - Parse an expression and return it.
325///
326/// expr ::= expr +,- expr -> lowest.
327/// expr ::= expr |,^,&,! expr -> middle.
328/// expr ::= expr *,/,%,<<,>> expr -> highest.
329/// expr ::= primaryexpr
330///
331bool AsmParser::ParseExpression(const MCExpr *&Res, SMLoc &EndLoc) {
332 // Parse the expression.
333 Res = 0;
334 if (ParsePrimaryExpr(Res, EndLoc) || ParseBinOpRHS(1, Res, EndLoc))
335 return true;
336
337 // Try to constant fold it up front, if possible.
338 int64_t Value;
339 if (Res->EvaluateAsAbsolute(Value))
340 Res = MCConstantExpr::Create(Value, getContext());
341
342 return false;
343}
344
345bool AsmParser::ParseParenExpression(const MCExpr *&Res, SMLoc &EndLoc) {
346 Res = 0;
347 return ParseParenExpr(Res, EndLoc) ||
348 ParseBinOpRHS(1, Res, EndLoc);
349}
350
351bool AsmParser::ParseAbsoluteExpression(int64_t &Res) {
352 const MCExpr *Expr;
353
354 SMLoc StartLoc = Lexer.getLoc();
355 if (ParseExpression(Expr))
356 return true;
357
358 if (!Expr->EvaluateAsAbsolute(Res))
359 return Error(StartLoc, "expected absolute expression");
360
361 return false;
362}
363
364static unsigned getBinOpPrecedence(AsmToken::TokenKind K,
365 MCBinaryExpr::Opcode &Kind) {
366 switch (K) {
367 default:
368 return 0; // not a binop.
369
370 // Lowest Precedence: &&, ||
371 case AsmToken::AmpAmp:
372 Kind = MCBinaryExpr::LAnd;
373 return 1;
374 case AsmToken::PipePipe:
375 Kind = MCBinaryExpr::LOr;
376 return 1;
377
378 // Low Precedence: +, -, ==, !=, <>, <, <=, >, >=
379 case AsmToken::Plus:
380 Kind = MCBinaryExpr::Add;
381 return 2;
382 case AsmToken::Minus:
383 Kind = MCBinaryExpr::Sub;
384 return 2;
385 case AsmToken::EqualEqual:
386 Kind = MCBinaryExpr::EQ;
387 return 2;
388 case AsmToken::ExclaimEqual:
389 case AsmToken::LessGreater:
390 Kind = MCBinaryExpr::NE;
391 return 2;
392 case AsmToken::Less:
393 Kind = MCBinaryExpr::LT;
394 return 2;
395 case AsmToken::LessEqual:
396 Kind = MCBinaryExpr::LTE;
397 return 2;
398 case AsmToken::Greater:
399 Kind = MCBinaryExpr::GT;
400 return 2;
401 case AsmToken::GreaterEqual:
402 Kind = MCBinaryExpr::GTE;
403 return 2;
404
405 // Intermediate Precedence: |, &, ^
406 //
407 // FIXME: gas seems to support '!' as an infix operator?
408 case AsmToken::Pipe:
409 Kind = MCBinaryExpr::Or;
410 return 3;
411 case AsmToken::Caret:
412 Kind = MCBinaryExpr::Xor;
413 return 3;
414 case AsmToken::Amp:
415 Kind = MCBinaryExpr::And;
416 return 3;
417
418 // Highest Precedence: *, /, %, <<, >>
419 case AsmToken::Star:
420 Kind = MCBinaryExpr::Mul;
421 return 4;
422 case AsmToken::Slash:
423 Kind = MCBinaryExpr::Div;
424 return 4;
425 case AsmToken::Percent:
426 Kind = MCBinaryExpr::Mod;
427 return 4;
428 case AsmToken::LessLess:
429 Kind = MCBinaryExpr::Shl;
430 return 4;
431 case AsmToken::GreaterGreater:
432 Kind = MCBinaryExpr::Shr;
433 return 4;
434 }
435}
436
437
438/// ParseBinOpRHS - Parse all binary operators with precedence >= 'Precedence'.
439/// Res contains the LHS of the expression on input.
440bool AsmParser::ParseBinOpRHS(unsigned Precedence, const MCExpr *&Res,
441 SMLoc &EndLoc) {
442 while (1) {
443 MCBinaryExpr::Opcode Kind = MCBinaryExpr::Add;
444 unsigned TokPrec = getBinOpPrecedence(Lexer.getKind(), Kind);
445
446 // If the next token is lower precedence than we are allowed to eat, return
447 // successfully with what we ate already.
448 if (TokPrec < Precedence)
449 return false;
450
451 Lex();
452
453 // Eat the next primary expression.
454 const MCExpr *RHS;
455 if (ParsePrimaryExpr(RHS, EndLoc)) return true;
456
457 // If BinOp binds less tightly with RHS than the operator after RHS, let
458 // the pending operator take RHS as its LHS.
459 MCBinaryExpr::Opcode Dummy;
460 unsigned NextTokPrec = getBinOpPrecedence(Lexer.getKind(), Dummy);
461 if (TokPrec < NextTokPrec) {
462 if (ParseBinOpRHS(Precedence+1, RHS, EndLoc)) return true;
463 }
464
465 // Merge LHS and RHS according to operator.
466 Res = MCBinaryExpr::Create(Kind, Res, RHS, getContext());
467 }
468}
469
470
471
472
473/// ParseStatement:
474/// ::= EndOfStatement
475/// ::= Label* Directive ...Operands... EndOfStatement
476/// ::= Label* Identifier OperandList* EndOfStatement
477bool AsmParser::ParseStatement() {
478 if (Lexer.is(AsmToken::EndOfStatement)) {
479 Lex();
480 return false;
481 }
482
483 // Statements always start with an identifier.
484 AsmToken ID = getTok();
485 SMLoc IDLoc = ID.getLoc();
486 StringRef IDVal;
487 if (ParseIdentifier(IDVal))
488 return TokError("unexpected token at start of statement");
489
490 // FIXME: Recurse on local labels?
491
492 // See what kind of statement we have.
493 switch (Lexer.getKind()) {
494 case AsmToken::Colon: {
495 // identifier ':' -> Label.
496 Lex();
497
498 // Diagnose attempt to use a variable as a label.
499 //
500 // FIXME: Diagnostics. Note the location of the definition as a label.
501 // FIXME: This doesn't diagnose assignment to a symbol which has been
502 // implicitly marked as external.
503 MCSymbol *Sym = CreateSymbol(IDVal);
504 if (!Sym->isUndefined())
505 return Error(IDLoc, "invalid symbol redefinition");
506
507 // Emit the label.
508 Out.EmitLabel(Sym);
509
510 return ParseStatement();
511 }
512
513 case AsmToken::Equal:
514 // identifier '=' ... -> assignment statement
515 Lex();
516
517 return ParseAssignment(IDVal);
518
519 default: // Normal instruction or directive.
520 break;
521 }
522
523 // Otherwise, we have a normal instruction or directive.
524 if (IDVal[0] == '.') {
525 // FIXME: This should be driven based on a hash lookup and callback.
526 if (IDVal == ".section")
527 return ParseDirectiveDarwinSection();
528 if (IDVal == ".text")
529 // FIXME: This changes behavior based on the -static flag to the
530 // assembler.
531 return ParseDirectiveSectionSwitch("__TEXT", "__text",
532 MCSectionMachO::S_ATTR_PURE_INSTRUCTIONS);
533 if (IDVal == ".const")
534 return ParseDirectiveSectionSwitch("__TEXT", "__const");
535 if (IDVal == ".static_const")
536 return ParseDirectiveSectionSwitch("__TEXT", "__static_const");
537 if (IDVal == ".cstring")
538 return ParseDirectiveSectionSwitch("__TEXT","__cstring",
539 MCSectionMachO::S_CSTRING_LITERALS);
540 if (IDVal == ".literal4")
541 return ParseDirectiveSectionSwitch("__TEXT", "__literal4",
542 MCSectionMachO::S_4BYTE_LITERALS,
543 4);
544 if (IDVal == ".literal8")
545 return ParseDirectiveSectionSwitch("__TEXT", "__literal8",
546 MCSectionMachO::S_8BYTE_LITERALS,
547 8);
548 if (IDVal == ".literal16")
549 return ParseDirectiveSectionSwitch("__TEXT","__literal16",
550 MCSectionMachO::S_16BYTE_LITERALS,
551 16);
552 if (IDVal == ".constructor")
553 return ParseDirectiveSectionSwitch("__TEXT","__constructor");
554 if (IDVal == ".destructor")
555 return ParseDirectiveSectionSwitch("__TEXT","__destructor");
556 if (IDVal == ".fvmlib_init0")
557 return ParseDirectiveSectionSwitch("__TEXT","__fvmlib_init0");
558 if (IDVal == ".fvmlib_init1")
559 return ParseDirectiveSectionSwitch("__TEXT","__fvmlib_init1");
560
561 // FIXME: The assembler manual claims that this has the self modify code
562 // flag, at least on x86-32, but that does not appear to be correct.
563 if (IDVal == ".symbol_stub")
564 return ParseDirectiveSectionSwitch("__TEXT","__symbol_stub",
565 MCSectionMachO::S_SYMBOL_STUBS |
566 MCSectionMachO::S_ATTR_PURE_INSTRUCTIONS,
567 // FIXME: Different on PPC and ARM.
568 0, 16);
569 // FIXME: PowerPC only?
570 if (IDVal == ".picsymbol_stub")
571 return ParseDirectiveSectionSwitch("__TEXT","__picsymbol_stub",
572 MCSectionMachO::S_SYMBOL_STUBS |
573 MCSectionMachO::S_ATTR_PURE_INSTRUCTIONS,
574 0, 26);
575 if (IDVal == ".data")
576 return ParseDirectiveSectionSwitch("__DATA", "__data");
577 if (IDVal == ".static_data")
578 return ParseDirectiveSectionSwitch("__DATA", "__static_data");
579
580 // FIXME: The section names of these two are misspelled in the assembler
581 // manual.
582 if (IDVal == ".non_lazy_symbol_pointer")
583 return ParseDirectiveSectionSwitch("__DATA", "__nl_symbol_ptr",
584 MCSectionMachO::S_NON_LAZY_SYMBOL_POINTERS,
585 4);
586 if (IDVal == ".lazy_symbol_pointer")
587 return ParseDirectiveSectionSwitch("__DATA", "__la_symbol_ptr",
588 MCSectionMachO::S_LAZY_SYMBOL_POINTERS,
589 4);
590
591 if (IDVal == ".dyld")
592 return ParseDirectiveSectionSwitch("__DATA", "__dyld");
593 if (IDVal == ".mod_init_func")
594 return ParseDirectiveSectionSwitch("__DATA", "__mod_init_func",
595 MCSectionMachO::S_MOD_INIT_FUNC_POINTERS,
596 4);
597 if (IDVal == ".mod_term_func")
598 return ParseDirectiveSectionSwitch("__DATA", "__mod_term_func",
599 MCSectionMachO::S_MOD_TERM_FUNC_POINTERS,
600 4);
601 if (IDVal == ".const_data")
602 return ParseDirectiveSectionSwitch("__DATA", "__const");
603
604
605 if (IDVal == ".objc_class")
606 return ParseDirectiveSectionSwitch("__OBJC", "__class",
607 MCSectionMachO::S_ATTR_NO_DEAD_STRIP);
608 if (IDVal == ".objc_meta_class")
609 return ParseDirectiveSectionSwitch("__OBJC", "__meta_class",
610 MCSectionMachO::S_ATTR_NO_DEAD_STRIP);
611 if (IDVal == ".objc_cat_cls_meth")
612 return ParseDirectiveSectionSwitch("__OBJC", "__cat_cls_meth",
613 MCSectionMachO::S_ATTR_NO_DEAD_STRIP);
614 if (IDVal == ".objc_cat_inst_meth")
615 return ParseDirectiveSectionSwitch("__OBJC", "__cat_inst_meth",
616 MCSectionMachO::S_ATTR_NO_DEAD_STRIP);
617 if (IDVal == ".objc_protocol")
618 return ParseDirectiveSectionSwitch("__OBJC", "__protocol",
619 MCSectionMachO::S_ATTR_NO_DEAD_STRIP);
620 if (IDVal == ".objc_string_object")
621 return ParseDirectiveSectionSwitch("__OBJC", "__string_object",
622 MCSectionMachO::S_ATTR_NO_DEAD_STRIP);
623 if (IDVal == ".objc_cls_meth")
624 return ParseDirectiveSectionSwitch("__OBJC", "__cls_meth",
625 MCSectionMachO::S_ATTR_NO_DEAD_STRIP);
626 if (IDVal == ".objc_inst_meth")
627 return ParseDirectiveSectionSwitch("__OBJC", "__inst_meth",
628 MCSectionMachO::S_ATTR_NO_DEAD_STRIP);
629 if (IDVal == ".objc_cls_refs")
630 return ParseDirectiveSectionSwitch("__OBJC", "__cls_refs",
631 MCSectionMachO::S_ATTR_NO_DEAD_STRIP |
632 MCSectionMachO::S_LITERAL_POINTERS,
633 4);
634 if (IDVal == ".objc_message_refs")
635 return ParseDirectiveSectionSwitch("__OBJC", "__message_refs",
636 MCSectionMachO::S_ATTR_NO_DEAD_STRIP |
637 MCSectionMachO::S_LITERAL_POINTERS,
638 4);
639 if (IDVal == ".objc_symbols")
640 return ParseDirectiveSectionSwitch("__OBJC", "__symbols",
641 MCSectionMachO::S_ATTR_NO_DEAD_STRIP);
642 if (IDVal == ".objc_category")
643 return ParseDirectiveSectionSwitch("__OBJC", "__category",
644 MCSectionMachO::S_ATTR_NO_DEAD_STRIP);
645 if (IDVal == ".objc_class_vars")
646 return ParseDirectiveSectionSwitch("__OBJC", "__class_vars",
647 MCSectionMachO::S_ATTR_NO_DEAD_STRIP);
648 if (IDVal == ".objc_instance_vars")
649 return ParseDirectiveSectionSwitch("__OBJC", "__instance_vars",
650 MCSectionMachO::S_ATTR_NO_DEAD_STRIP);
651 if (IDVal == ".objc_module_info")
652 return ParseDirectiveSectionSwitch("__OBJC", "__module_info",
653 MCSectionMachO::S_ATTR_NO_DEAD_STRIP);
654 if (IDVal == ".objc_class_names")
655 return ParseDirectiveSectionSwitch("__TEXT", "__cstring",
656 MCSectionMachO::S_CSTRING_LITERALS);
657 if (IDVal == ".objc_meth_var_types")
658 return ParseDirectiveSectionSwitch("__TEXT", "__cstring",
659 MCSectionMachO::S_CSTRING_LITERALS);
660 if (IDVal == ".objc_meth_var_names")
661 return ParseDirectiveSectionSwitch("__TEXT", "__cstring",
662 MCSectionMachO::S_CSTRING_LITERALS);
663 if (IDVal == ".objc_selector_strs")
664 return ParseDirectiveSectionSwitch("__OBJC", "__selector_strs",
665 MCSectionMachO::S_CSTRING_LITERALS);
666
667 // Assembler features
668 if (IDVal == ".set")
669 return ParseDirectiveSet();
670
671 // Data directives
672
673 if (IDVal == ".ascii")
674 return ParseDirectiveAscii(false);
675 if (IDVal == ".asciz")
676 return ParseDirectiveAscii(true);
677
678 if (IDVal == ".byte")
679 return ParseDirectiveValue(1);
680 if (IDVal == ".short")
681 return ParseDirectiveValue(2);
682 if (IDVal == ".long")
683 return ParseDirectiveValue(4);
684 if (IDVal == ".quad")
685 return ParseDirectiveValue(8);
686
687 // FIXME: Target hooks for IsPow2.
688 if (IDVal == ".align")
689 return ParseDirectiveAlign(/*IsPow2=*/true, /*ExprSize=*/1);
690 if (IDVal == ".align32")
691 return ParseDirectiveAlign(/*IsPow2=*/true, /*ExprSize=*/4);
692 if (IDVal == ".balign")
693 return ParseDirectiveAlign(/*IsPow2=*/false, /*ExprSize=*/1);
694 if (IDVal == ".balignw")
695 return ParseDirectiveAlign(/*IsPow2=*/false, /*ExprSize=*/2);
696 if (IDVal == ".balignl")
697 return ParseDirectiveAlign(/*IsPow2=*/false, /*ExprSize=*/4);
698 if (IDVal == ".p2align")
699 return ParseDirectiveAlign(/*IsPow2=*/true, /*ExprSize=*/1);
700 if (IDVal == ".p2alignw")
701 return ParseDirectiveAlign(/*IsPow2=*/true, /*ExprSize=*/2);
702 if (IDVal == ".p2alignl")
703 return ParseDirectiveAlign(/*IsPow2=*/true, /*ExprSize=*/4);
704
705 if (IDVal == ".org")
706 return ParseDirectiveOrg();
707
708 if (IDVal == ".fill")
709 return ParseDirectiveFill();
710 if (IDVal == ".space")
711 return ParseDirectiveSpace();
712
713 // Symbol attribute directives
714
715 if (IDVal == ".globl" || IDVal == ".global")
716 return ParseDirectiveSymbolAttribute(MCSA_Global);
717 if (IDVal == ".hidden")
718 return ParseDirectiveSymbolAttribute(MCSA_Hidden);
719 if (IDVal == ".indirect_symbol")
720 return ParseDirectiveSymbolAttribute(MCSA_IndirectSymbol);
721 if (IDVal == ".internal")
722 return ParseDirectiveSymbolAttribute(MCSA_Internal);
723 if (IDVal == ".lazy_reference")
724 return ParseDirectiveSymbolAttribute(MCSA_LazyReference);
725 if (IDVal == ".no_dead_strip")
726 return ParseDirectiveSymbolAttribute(MCSA_NoDeadStrip);
727 if (IDVal == ".private_extern")
728 return ParseDirectiveSymbolAttribute(MCSA_PrivateExtern);
729 if (IDVal == ".protected")
730 return ParseDirectiveSymbolAttribute(MCSA_Protected);
731 if (IDVal == ".reference")
732 return ParseDirectiveSymbolAttribute(MCSA_Reference);
733 if (IDVal == ".weak")
734 return ParseDirectiveSymbolAttribute(MCSA_Weak);
735 if (IDVal == ".weak_definition")
736 return ParseDirectiveSymbolAttribute(MCSA_WeakDefinition);
737 if (IDVal == ".weak_reference")
738 return ParseDirectiveSymbolAttribute(MCSA_WeakReference);
739
740 if (IDVal == ".comm")
741 return ParseDirectiveComm(/*IsLocal=*/false);
742 if (IDVal == ".lcomm")
743 return ParseDirectiveComm(/*IsLocal=*/true);
744 if (IDVal == ".zerofill")
745 return ParseDirectiveDarwinZerofill();
746 if (IDVal == ".desc")
747 return ParseDirectiveDarwinSymbolDesc();
748 if (IDVal == ".lsym")
749 return ParseDirectiveDarwinLsym();
750
751 if (IDVal == ".subsections_via_symbols")
752 return ParseDirectiveDarwinSubsectionsViaSymbols();
753 if (IDVal == ".abort")
754 return ParseDirectiveAbort();
755 if (IDVal == ".include")
756 return ParseDirectiveInclude();
757 if (IDVal == ".dump")
758 return ParseDirectiveDarwinDumpOrLoad(IDLoc, /*IsDump=*/true);
759 if (IDVal == ".load")
760 return ParseDirectiveDarwinDumpOrLoad(IDLoc, /*IsLoad=*/false);
761
762 // Look up the handler in the handler table,
763 bool(AsmParser::*Handler)(StringRef, SMLoc) = DirectiveMap[IDVal];
764 if (Handler)
765 return (this->*Handler)(IDVal, IDLoc);
766
767 // Target hook for parsing target specific directives.
768 if (!getTargetParser().ParseDirective(ID))
769 return false;
770
771 Warning(IDLoc, "ignoring directive for now");
772 EatToEndOfStatement();
773 return false;
774 }
775
776
777 SmallVector<MCParsedAsmOperand*, 8> ParsedOperands;
778 if (getTargetParser().ParseInstruction(IDVal, IDLoc, ParsedOperands))
779 // FIXME: Leaking ParsedOperands on failure.
780 return true;
781
782 if (Lexer.isNot(AsmToken::EndOfStatement))
783 // FIXME: Leaking ParsedOperands on failure.
784 return TokError("unexpected token in argument list");
785
786 // Eat the end of statement marker.
787 Lex();
788
789
790 MCInst Inst;
791
792 bool MatchFail = getTargetParser().MatchInstruction(ParsedOperands, Inst);
793
794 // Free any parsed operands.
795 for (unsigned i = 0, e = ParsedOperands.size(); i != e; ++i)
796 delete ParsedOperands[i];
797
798 if (MatchFail) {
799 // FIXME: We should give nicer diagnostics about the exact failure.
800 Error(IDLoc, "unrecognized instruction");
801 return true;
802 }
803
804 // Instruction is good, process it.
805 Out.EmitInstruction(Inst);
806
807 // Skip to end of line for now.
808 return false;
809}
810
811bool AsmParser::ParseAssignment(const StringRef &Name) {
812 // FIXME: Use better location, we should use proper tokens.
813 SMLoc EqualLoc = Lexer.getLoc();
814
815 const MCExpr *Value;
816 SMLoc StartLoc = Lexer.getLoc();
817 if (ParseExpression(Value))
818 return true;
819
820 if (Lexer.isNot(AsmToken::EndOfStatement))
821 return TokError("unexpected token in assignment");
822
823 // Eat the end of statement marker.
824 Lex();
825
826 // Validate that the LHS is allowed to be a variable (either it has not been
827 // used as a symbol, or it is an absolute symbol).
828 MCSymbol *Sym = getContext().LookupSymbol(Name);
829 if (Sym) {
830 // Diagnose assignment to a label.
831 //
832 // FIXME: Diagnostics. Note the location of the definition as a label.
833 // FIXME: Diagnose assignment to protected identifier (e.g., register name).
834 if (!Sym->isUndefined() && !Sym->isAbsolute())
835 return Error(EqualLoc, "redefinition of '" + Name + "'");
836 else if (!Sym->isVariable())
837 return Error(EqualLoc, "invalid assignment to '" + Name + "'");
838 else if (!isa<MCConstantExpr>(Sym->getValue()))
839 return Error(EqualLoc, "invalid reassignment of non-absolute variable '" +
840 Name + "'");
841 } else
842 Sym = CreateSymbol(Name);
843
844 // FIXME: Handle '.'.
845
846 // Do the assignment.
847 Out.EmitAssignment(Sym, Value);
848
849 return false;
850}
851
852/// ParseIdentifier:
853/// ::= identifier
854/// ::= string
855bool AsmParser::ParseIdentifier(StringRef &Res) {
856 if (Lexer.isNot(AsmToken::Identifier) &&
857 Lexer.isNot(AsmToken::String))
858 return true;
859
860 Res = getTok().getIdentifier();
861
862 Lex(); // Consume the identifier token.
863
864 return false;
865}
866
867/// ParseDirectiveSet:
868/// ::= .set identifier ',' expression
869bool AsmParser::ParseDirectiveSet() {
870 StringRef Name;
871
872 if (ParseIdentifier(Name))
873 return TokError("expected identifier after '.set' directive");
874
875 if (Lexer.isNot(AsmToken::Comma))
876 return TokError("unexpected token in '.set'");
877 Lex();
878
879 return ParseAssignment(Name);
880}
881
882/// ParseDirectiveSection:
883/// ::= .section identifier (',' identifier)*
884/// FIXME: This should actually parse out the segment, section, attributes and
885/// sizeof_stub fields.
886bool AsmParser::ParseDirectiveDarwinSection() {
887 SMLoc Loc = Lexer.getLoc();
888
889 StringRef SectionName;
890 if (ParseIdentifier(SectionName))
891 return Error(Loc, "expected identifier after '.section' directive");
892
893 // Verify there is a following comma.
894 if (!Lexer.is(AsmToken::Comma))
895 return TokError("unexpected token in '.section' directive");
896
897 std::string SectionSpec = SectionName;
898 SectionSpec += ",";
899
900 // Add all the tokens until the end of the line, ParseSectionSpecifier will
901 // handle this.
902 StringRef EOL = Lexer.LexUntilEndOfStatement();
903 SectionSpec.append(EOL.begin(), EOL.end());
904
905 Lex();
906 if (Lexer.isNot(AsmToken::EndOfStatement))
907 return TokError("unexpected token in '.section' directive");
908 Lex();
909
910
911 StringRef Segment, Section;
912 unsigned TAA, StubSize;
913 std::string ErrorStr =
914 MCSectionMachO::ParseSectionSpecifier(SectionSpec, Segment, Section,
915 TAA, StubSize);
916
917 if (!ErrorStr.empty())
918 return Error(Loc, ErrorStr.c_str());
919
920 // FIXME: Arch specific.
921 bool isText = Segment == "__TEXT"; // FIXME: Hack.
922 Out.SwitchSection(getMachOSection(Segment, Section, TAA, StubSize,
923 isText ? SectionKind::getText()
924 : SectionKind::getDataRel()));
925 return false;
926}
927
928/// ParseDirectiveSectionSwitch -
929bool AsmParser::ParseDirectiveSectionSwitch(const char *Segment,
930 const char *Section,
931 unsigned TAA, unsigned Align,
932 unsigned StubSize) {
933 if (Lexer.isNot(AsmToken::EndOfStatement))
934 return TokError("unexpected token in section switching directive");
935 Lex();
936
937 // FIXME: Arch specific.
938 bool isText = StringRef(Segment) == "__TEXT"; // FIXME: Hack.
939 Out.SwitchSection(getMachOSection(Segment, Section, TAA, StubSize,
940 isText ? SectionKind::getText()
941 : SectionKind::getDataRel()));
942
943 // Set the implicit alignment, if any.
944 //
945 // FIXME: This isn't really what 'as' does; I think it just uses the implicit
946 // alignment on the section (e.g., if one manually inserts bytes into the
947 // section, then just issueing the section switch directive will not realign
948 // the section. However, this is arguably more reasonable behavior, and there
949 // is no good reason for someone to intentionally emit incorrectly sized
950 // values into the implicitly aligned sections.
951 if (Align)
952 Out.EmitValueToAlignment(Align, 0, 1, 0);
953
954 return false;
955}
956
957bool AsmParser::ParseEscapedString(std::string &Data) {
958 assert(Lexer.is(AsmToken::String) && "Unexpected current token!");
959
960 Data = "";
961 StringRef Str = getTok().getStringContents();
962 for (unsigned i = 0, e = Str.size(); i != e; ++i) {
963 if (Str[i] != '\\') {
964 Data += Str[i];
965 continue;
966 }
967
968 // Recognize escaped characters. Note that this escape semantics currently
969 // loosely follows Darwin 'as'. Notably, it doesn't support hex escapes.
970 ++i;
971 if (i == e)
972 return TokError("unexpected backslash at end of string");
973
974 // Recognize octal sequences.
975 if ((unsigned) (Str[i] - '0') <= 7) {
976 // Consume up to three octal characters.
977 unsigned Value = Str[i] - '0';
978
979 if (i + 1 != e && ((unsigned) (Str[i + 1] - '0')) <= 7) {
980 ++i;
981 Value = Value * 8 + (Str[i] - '0');
982
983 if (i + 1 != e && ((unsigned) (Str[i + 1] - '0')) <= 7) {
984 ++i;
985 Value = Value * 8 + (Str[i] - '0');
986 }
987 }
988
989 if (Value > 255)
990 return TokError("invalid octal escape sequence (out of range)");
991
992 Data += (unsigned char) Value;
993 continue;
994 }
995
996 // Otherwise recognize individual escapes.
997 switch (Str[i]) {
998 default:
999 // Just reject invalid escape sequences for now.
1000 return TokError("invalid escape sequence (unrecognized character)");
1001
1002 case 'b': Data += '\b'; break;
1003 case 'f': Data += '\f'; break;
1004 case 'n': Data += '\n'; break;
1005 case 'r': Data += '\r'; break;
1006 case 't': Data += '\t'; break;
1007 case '"': Data += '"'; break;
1008 case '\\': Data += '\\'; break;
1009 }
1010 }
1011
1012 return false;
1013}
1014
1015/// ParseDirectiveAscii:
1016/// ::= ( .ascii | .asciz ) [ "string" ( , "string" )* ]
1017bool AsmParser::ParseDirectiveAscii(bool ZeroTerminated) {
1018 if (Lexer.isNot(AsmToken::EndOfStatement)) {
1019 for (;;) {
1020 if (Lexer.isNot(AsmToken::String))
1021 return TokError("expected string in '.ascii' or '.asciz' directive");
1022
1023 std::string Data;
1024 if (ParseEscapedString(Data))
1025 return true;
1026
1027 Out.EmitBytes(Data, DEFAULT_ADDRSPACE);
1028 if (ZeroTerminated)
1029 Out.EmitBytes(StringRef("\0", 1), DEFAULT_ADDRSPACE);
1030
1031 Lex();
1032
1033 if (Lexer.is(AsmToken::EndOfStatement))
1034 break;
1035
1036 if (Lexer.isNot(AsmToken::Comma))
1037 return TokError("unexpected token in '.ascii' or '.asciz' directive");
1038 Lex();
1039 }
1040 }
1041
1042 Lex();
1043 return false;
1044}
1045
1046/// ParseDirectiveValue
1047/// ::= (.byte | .short | ... ) [ expression (, expression)* ]
1048bool AsmParser::ParseDirectiveValue(unsigned Size) {
1049 if (Lexer.isNot(AsmToken::EndOfStatement)) {
1050 for (;;) {
1051 const MCExpr *Value;
1052 SMLoc ATTRIBUTE_UNUSED StartLoc = Lexer.getLoc();
1053 if (ParseExpression(Value))
1054 return true;
1055
1056 Out.EmitValue(Value, Size, DEFAULT_ADDRSPACE);
1057
1058 if (Lexer.is(AsmToken::EndOfStatement))
1059 break;
1060
1061 // FIXME: Improve diagnostic.
1062 if (Lexer.isNot(AsmToken::Comma))
1063 return TokError("unexpected token in directive");
1064 Lex();
1065 }
1066 }
1067
1068 Lex();
1069 return false;
1070}
1071
1072/// ParseDirectiveSpace
1073/// ::= .space expression [ , expression ]
1074bool AsmParser::ParseDirectiveSpace() {
1075 int64_t NumBytes;
1076 if (ParseAbsoluteExpression(NumBytes))
1077 return true;
1078
1079 int64_t FillExpr = 0;
1080 bool HasFillExpr = false;
1081 if (Lexer.isNot(AsmToken::EndOfStatement)) {
1082 if (Lexer.isNot(AsmToken::Comma))
1083 return TokError("unexpected token in '.space' directive");
1084 Lex();
1085
1086 if (ParseAbsoluteExpression(FillExpr))
1087 return true;
1088
1089 HasFillExpr = true;
1090
1091 if (Lexer.isNot(AsmToken::EndOfStatement))
1092 return TokError("unexpected token in '.space' directive");
1093 }
1094
1095 Lex();
1096
1097 if (NumBytes <= 0)
1098 return TokError("invalid number of bytes in '.space' directive");
1099
1100 // FIXME: Sometimes the fill expr is 'nop' if it isn't supplied, instead of 0.
1101 Out.EmitFill(NumBytes, FillExpr, DEFAULT_ADDRSPACE);
1102
1103 return false;
1104}
1105
1106/// ParseDirectiveFill
1107/// ::= .fill expression , expression , expression
1108bool AsmParser::ParseDirectiveFill() {
1109 int64_t NumValues;
1110 if (ParseAbsoluteExpression(NumValues))
1111 return true;
1112
1113 if (Lexer.isNot(AsmToken::Comma))
1114 return TokError("unexpected token in '.fill' directive");
1115 Lex();
1116
1117 int64_t FillSize;
1118 if (ParseAbsoluteExpression(FillSize))
1119 return true;
1120
1121 if (Lexer.isNot(AsmToken::Comma))
1122 return TokError("unexpected token in '.fill' directive");
1123 Lex();
1124
1125 int64_t FillExpr;
1126 if (ParseAbsoluteExpression(FillExpr))
1127 return true;
1128
1129 if (Lexer.isNot(AsmToken::EndOfStatement))
1130 return TokError("unexpected token in '.fill' directive");
1131
1132 Lex();
1133
1134 if (FillSize != 1 && FillSize != 2 && FillSize != 4 && FillSize != 8)
1135 return TokError("invalid '.fill' size, expected 1, 2, 4, or 8");
1136
1137 for (uint64_t i = 0, e = NumValues; i != e; ++i)
1138 Out.EmitValue(MCConstantExpr::Create(FillExpr, getContext()), FillSize,
1139 DEFAULT_ADDRSPACE);
1140
1141 return false;
1142}
1143
1144/// ParseDirectiveOrg
1145/// ::= .org expression [ , expression ]
1146bool AsmParser::ParseDirectiveOrg() {
1147 const MCExpr *Offset;
1148 SMLoc StartLoc = Lexer.getLoc();
1149 if (ParseExpression(Offset))
1150 return true;
1151
1152 // Parse optional fill expression.
1153 int64_t FillExpr = 0;
1154 if (Lexer.isNot(AsmToken::EndOfStatement)) {
1155 if (Lexer.isNot(AsmToken::Comma))
1156 return TokError("unexpected token in '.org' directive");
1157 Lex();
1158
1159 if (ParseAbsoluteExpression(FillExpr))
1160 return true;
1161
1162 if (Lexer.isNot(AsmToken::EndOfStatement))
1163 return TokError("unexpected token in '.org' directive");
1164 }
1165
1166 Lex();
1167
1168 // FIXME: Only limited forms of relocatable expressions are accepted here, it
1169 // has to be relative to the current section.
1170 Out.EmitValueToOffset(Offset, FillExpr);
1171
1172 return false;
1173}
1174
1175/// ParseDirectiveAlign
1176/// ::= {.align, ...} expression [ , expression [ , expression ]]
1177bool AsmParser::ParseDirectiveAlign(bool IsPow2, unsigned ValueSize) {
1178 SMLoc AlignmentLoc = Lexer.getLoc();
1179 int64_t Alignment;
1180 if (ParseAbsoluteExpression(Alignment))
1181 return true;
1182
1183 SMLoc MaxBytesLoc;
1184 bool HasFillExpr = false;
1185 int64_t FillExpr = 0;
1186 int64_t MaxBytesToFill = 0;
1187 if (Lexer.isNot(AsmToken::EndOfStatement)) {
1188 if (Lexer.isNot(AsmToken::Comma))
1189 return TokError("unexpected token in directive");
1190 Lex();
1191
1192 // The fill expression can be omitted while specifying a maximum number of
1193 // alignment bytes, e.g:
1194 // .align 3,,4
1195 if (Lexer.isNot(AsmToken::Comma)) {
1196 HasFillExpr = true;
1197 if (ParseAbsoluteExpression(FillExpr))
1198 return true;
1199 }
1200
1201 if (Lexer.isNot(AsmToken::EndOfStatement)) {
1202 if (Lexer.isNot(AsmToken::Comma))
1203 return TokError("unexpected token in directive");
1204 Lex();
1205
1206 MaxBytesLoc = Lexer.getLoc();
1207 if (ParseAbsoluteExpression(MaxBytesToFill))
1208 return true;
1209
1210 if (Lexer.isNot(AsmToken::EndOfStatement))
1211 return TokError("unexpected token in directive");
1212 }
1213 }
1214
1215 Lex();
1216
1217 if (!HasFillExpr) {
1218 // FIXME: Sometimes fill with nop.
1219 FillExpr = 0;
1220 }
1221
1222 // Compute alignment in bytes.
1223 if (IsPow2) {
1224 // FIXME: Diagnose overflow.
1225 if (Alignment >= 32) {
1226 Error(AlignmentLoc, "invalid alignment value");
1227 Alignment = 31;
1228 }
1229
1230 Alignment = 1ULL << Alignment;
1231 }
1232
1233 // Diagnose non-sensical max bytes to align.
1234 if (MaxBytesLoc.isValid()) {
1235 if (MaxBytesToFill < 1) {
1236 Error(MaxBytesLoc, "alignment directive can never be satisfied in this "
1237 "many bytes, ignoring maximum bytes expression");
1238 MaxBytesToFill = 0;
1239 }
1240
1241 if (MaxBytesToFill >= Alignment) {
1242 Warning(MaxBytesLoc, "maximum bytes expression exceeds alignment and "
1243 "has no effect");
1244 MaxBytesToFill = 0;
1245 }
1246 }
1247
1248 // FIXME: hard code the parser to use EmitCodeAlignment for text when using
1249 // the TextAlignFillValue.
1250 if(Out.getCurrentSection()->getKind().isText() &&
1251 Lexer.getMAI().getTextAlignFillValue() == FillExpr)
1252 Out.EmitCodeAlignment(Alignment, MaxBytesToFill);
1253 else
1254 // FIXME: Target specific behavior about how the "extra" bytes are filled.
1255 Out.EmitValueToAlignment(Alignment, FillExpr, ValueSize, MaxBytesToFill);
1256
1257 return false;
1258}
1259
1260/// ParseDirectiveSymbolAttribute
1261/// ::= { ".globl", ".weak", ... } [ identifier ( , identifier )* ]
1262bool AsmParser::ParseDirectiveSymbolAttribute(MCSymbolAttr Attr) {
1263 if (Lexer.isNot(AsmToken::EndOfStatement)) {
1264 for (;;) {
1265 StringRef Name;
1266
1267 if (ParseIdentifier(Name))
1268 return TokError("expected identifier in directive");
1269
1270 MCSymbol *Sym = CreateSymbol(Name);
1271
1272 Out.EmitSymbolAttribute(Sym, Attr);
1273
1274 if (Lexer.is(AsmToken::EndOfStatement))
1275 break;
1276
1277 if (Lexer.isNot(AsmToken::Comma))
1278 return TokError("unexpected token in directive");
1279 Lex();
1280 }
1281 }
1282
1283 Lex();
1284 return false;
1285}
1286
1287/// ParseDirectiveDarwinSymbolDesc
1288/// ::= .desc identifier , expression
1289bool AsmParser::ParseDirectiveDarwinSymbolDesc() {
1290 StringRef Name;
1291 if (ParseIdentifier(Name))
1292 return TokError("expected identifier in directive");
1293
1294 // Handle the identifier as the key symbol.
1295 MCSymbol *Sym = CreateSymbol(Name);
1296
1297 if (Lexer.isNot(AsmToken::Comma))
1298 return TokError("unexpected token in '.desc' directive");
1299 Lex();
1300
1301 SMLoc DescLoc = Lexer.getLoc();
1302 int64_t DescValue;
1303 if (ParseAbsoluteExpression(DescValue))
1304 return true;
1305
1306 if (Lexer.isNot(AsmToken::EndOfStatement))
1307 return TokError("unexpected token in '.desc' directive");
1308
1309 Lex();
1310
1311 // Set the n_desc field of this Symbol to this DescValue
1312 Out.EmitSymbolDesc(Sym, DescValue);
1313
1314 return false;
1315}
1316
1317/// ParseDirectiveComm
1318/// ::= ( .comm | .lcomm ) identifier , size_expression [ , align_expression ]
1319bool AsmParser::ParseDirectiveComm(bool IsLocal) {
1320 SMLoc IDLoc = Lexer.getLoc();
1321 StringRef Name;
1322 if (ParseIdentifier(Name))
1323 return TokError("expected identifier in directive");
1324
1325 // Handle the identifier as the key symbol.
1326 MCSymbol *Sym = CreateSymbol(Name);
1327
1328 if (Lexer.isNot(AsmToken::Comma))
1329 return TokError("unexpected token in directive");
1330 Lex();
1331
1332 int64_t Size;
1333 SMLoc SizeLoc = Lexer.getLoc();
1334 if (ParseAbsoluteExpression(Size))
1335 return true;
1336
1337 int64_t Pow2Alignment = 0;
1338 SMLoc Pow2AlignmentLoc;
1339 if (Lexer.is(AsmToken::Comma)) {
1340 Lex();
1341 Pow2AlignmentLoc = Lexer.getLoc();
1342 if (ParseAbsoluteExpression(Pow2Alignment))
1343 return true;
1344
1345 // If this target takes alignments in bytes (not log) validate and convert.
1346 if (Lexer.getMAI().getAlignmentIsInBytes()) {
1347 if (!isPowerOf2_64(Pow2Alignment))
1348 return Error(Pow2AlignmentLoc, "alignment must be a power of 2");
1349 Pow2Alignment = Log2_64(Pow2Alignment);
1350 }
1351 }
1352
1353 if (Lexer.isNot(AsmToken::EndOfStatement))
1354 return TokError("unexpected token in '.comm' or '.lcomm' directive");
1355
1356 Lex();
1357
1358 // NOTE: a size of zero for a .comm should create a undefined symbol
1359 // but a size of .lcomm creates a bss symbol of size zero.
1360 if (Size < 0)
1361 return Error(SizeLoc, "invalid '.comm' or '.lcomm' directive size, can't "
1362 "be less than zero");
1363
1364 // NOTE: The alignment in the directive is a power of 2 value, the assember
1365 // may internally end up wanting an alignment in bytes.
1366 // FIXME: Diagnose overflow.
1367 if (Pow2Alignment < 0)
1368 return Error(Pow2AlignmentLoc, "invalid '.comm' or '.lcomm' directive "
1369 "alignment, can't be less than zero");
1370
1371 if (!Sym->isUndefined())
1372 return Error(IDLoc, "invalid symbol redefinition");
1373
1374 // '.lcomm' is equivalent to '.zerofill'.
1375 // Create the Symbol as a common or local common with Size and Pow2Alignment
1376 if (IsLocal) {
1377 Out.EmitZerofill(getMachOSection("__DATA", "__bss",
1378 MCSectionMachO::S_ZEROFILL, 0,
1379 SectionKind::getBSS()),
1380 Sym, Size, 1 << Pow2Alignment);
1381 return false;
1382 }
1383
1384 Out.EmitCommonSymbol(Sym, Size, 1 << Pow2Alignment);
1385 return false;
1386}
1387
1388/// ParseDirectiveDarwinZerofill
1389/// ::= .zerofill segname , sectname [, identifier , size_expression [
1390/// , align_expression ]]
1391bool AsmParser::ParseDirectiveDarwinZerofill() {
1392 // FIXME: Handle quoted names here.
1393
1394 if (Lexer.isNot(AsmToken::Identifier))
1395 return TokError("expected segment name after '.zerofill' directive");
1396 StringRef Segment = getTok().getString();
1397 Lex();
1398
1399 if (Lexer.isNot(AsmToken::Comma))
1400 return TokError("unexpected token in directive");
1401 Lex();
1402
1403 if (Lexer.isNot(AsmToken::Identifier))
1404 return TokError("expected section name after comma in '.zerofill' "
1405 "directive");
1406 StringRef Section = getTok().getString();
1407 Lex();
1408
1409 // If this is the end of the line all that was wanted was to create the
1410 // the section but with no symbol.
1411 if (Lexer.is(AsmToken::EndOfStatement)) {
1412 // Create the zerofill section but no symbol
1413 Out.EmitZerofill(getMachOSection(Segment, Section,
1414 MCSectionMachO::S_ZEROFILL, 0,
1415 SectionKind::getBSS()));
1416 return false;
1417 }
1418
1419 if (Lexer.isNot(AsmToken::Comma))
1420 return TokError("unexpected token in directive");
1421 Lex();
1422
1423 if (Lexer.isNot(AsmToken::Identifier))
1424 return TokError("expected identifier in directive");
1425
1426 // handle the identifier as the key symbol.
1427 SMLoc IDLoc = Lexer.getLoc();
1428 MCSymbol *Sym = CreateSymbol(getTok().getString());
1429 Lex();
1430
1431 if (Lexer.isNot(AsmToken::Comma))
1432 return TokError("unexpected token in directive");
1433 Lex();
1434
1435 int64_t Size;
1436 SMLoc SizeLoc = Lexer.getLoc();
1437 if (ParseAbsoluteExpression(Size))
1438 return true;
1439
1440 int64_t Pow2Alignment = 0;
1441 SMLoc Pow2AlignmentLoc;
1442 if (Lexer.is(AsmToken::Comma)) {
1443 Lex();
1444 Pow2AlignmentLoc = Lexer.getLoc();
1445 if (ParseAbsoluteExpression(Pow2Alignment))
1446 return true;
1447 }
1448
1449 if (Lexer.isNot(AsmToken::EndOfStatement))
1450 return TokError("unexpected token in '.zerofill' directive");
1451
1452 Lex();
1453
1454 if (Size < 0)
1455 return Error(SizeLoc, "invalid '.zerofill' directive size, can't be less "
1456 "than zero");
1457
1458 // NOTE: The alignment in the directive is a power of 2 value, the assember
1459 // may internally end up wanting an alignment in bytes.
1460 // FIXME: Diagnose overflow.
1461 if (Pow2Alignment < 0)
1462 return Error(Pow2AlignmentLoc, "invalid '.zerofill' directive alignment, "
1463 "can't be less than zero");
1464
1465 if (!Sym->isUndefined())
1466 return Error(IDLoc, "invalid symbol redefinition");
1467
1468 // Create the zerofill Symbol with Size and Pow2Alignment
1469 //
1470 // FIXME: Arch specific.
1471 Out.EmitZerofill(getMachOSection(Segment, Section,
1472 MCSectionMachO::S_ZEROFILL, 0,
1473 SectionKind::getBSS()),
1474 Sym, Size, 1 << Pow2Alignment);
1475
1476 return false;
1477}
1478
1479/// ParseDirectiveDarwinSubsectionsViaSymbols
1480/// ::= .subsections_via_symbols
1481bool AsmParser::ParseDirectiveDarwinSubsectionsViaSymbols() {
1482 if (Lexer.isNot(AsmToken::EndOfStatement))
1483 return TokError("unexpected token in '.subsections_via_symbols' directive");
1484
1485 Lex();
1486
1487 Out.EmitAssemblerFlag(MCAF_SubsectionsViaSymbols);
1488
1489 return false;
1490}
1491
1492/// ParseDirectiveAbort
1493/// ::= .abort [ "abort_string" ]
1494bool AsmParser::ParseDirectiveAbort() {
1495 // FIXME: Use loc from directive.
1496 SMLoc Loc = Lexer.getLoc();
1497
1498 StringRef Str = "";
1499 if (Lexer.isNot(AsmToken::EndOfStatement)) {
1500 if (Lexer.isNot(AsmToken::String))
1501 return TokError("expected string in '.abort' directive");
1502
1503 Str = getTok().getString();
1504
1505 Lex();
1506 }
1507
1508 if (Lexer.isNot(AsmToken::EndOfStatement))
1509 return TokError("unexpected token in '.abort' directive");
1510
1511 Lex();
1512
1513 // FIXME: Handle here.
1514 if (Str.empty())
1515 Error(Loc, ".abort detected. Assembly stopping.");
1516 else
1517 Error(Loc, ".abort '" + Str + "' detected. Assembly stopping.");
1518
1519 return false;
1520}
1521
1522/// ParseDirectiveLsym
1523/// ::= .lsym identifier , expression
1524bool AsmParser::ParseDirectiveDarwinLsym() {
1525 StringRef Name;
1526 if (ParseIdentifier(Name))
1527 return TokError("expected identifier in directive");
1528
1529 // Handle the identifier as the key symbol.
1530 MCSymbol *Sym = CreateSymbol(Name);
1531
1532 if (Lexer.isNot(AsmToken::Comma))
1533 return TokError("unexpected token in '.lsym' directive");
1534 Lex();
1535
1536 const MCExpr *Value;
1537 SMLoc StartLoc = Lexer.getLoc();
1538 if (ParseExpression(Value))
1539 return true;
1540
1541 if (Lexer.isNot(AsmToken::EndOfStatement))
1542 return TokError("unexpected token in '.lsym' directive");
1543
1544 Lex();
1545
1546 // We don't currently support this directive.
1547 //
1548 // FIXME: Diagnostic location!
1549 (void) Sym;
1550 return TokError("directive '.lsym' is unsupported");
1551}
1552
1553/// ParseDirectiveInclude
1554/// ::= .include "filename"
1555bool AsmParser::ParseDirectiveInclude() {
1556 if (Lexer.isNot(AsmToken::String))
1557 return TokError("expected string in '.include' directive");
1558
1559 std::string Filename = getTok().getString();
1560 SMLoc IncludeLoc = Lexer.getLoc();
1561 Lex();
1562
1563 if (Lexer.isNot(AsmToken::EndOfStatement))
1564 return TokError("unexpected token in '.include' directive");
1565
1566 // Strip the quotes.
1567 Filename = Filename.substr(1, Filename.size()-2);
1568
1569 // Attempt to switch the lexer to the included file before consuming the end
1570 // of statement to avoid losing it when we switch.
1571 if (EnterIncludeFile(Filename)) {
1572 PrintMessage(IncludeLoc,
1573 "Could not find include file '" + Filename + "'",
1574 "error");
1575 return true;
1576 }
1577
1578 return false;
1579}
1580
1581/// ParseDirectiveDarwinDumpOrLoad
1582/// ::= ( .dump | .load ) "filename"
1583bool AsmParser::ParseDirectiveDarwinDumpOrLoad(SMLoc IDLoc, bool IsDump) {
1584 if (Lexer.isNot(AsmToken::String))
1585 return TokError("expected string in '.dump' or '.load' directive");
1586
1587 Lex();
1588
1589 if (Lexer.isNot(AsmToken::EndOfStatement))
1590 return TokError("unexpected token in '.dump' or '.load' directive");
1591
1592 Lex();
1593
1594 // FIXME: If/when .dump and .load are implemented they will be done in the
1595 // the assembly parser and not have any need for an MCStreamer API.
1596 if (IsDump)
1597 Warning(IDLoc, "ignoring directive .dump for now");
1598 else
1599 Warning(IDLoc, "ignoring directive .load for now");
1600
1601 return false;
1602}
1603
1604/// ParseDirectiveIf
1605/// ::= .if expression
1606bool AsmParser::ParseDirectiveIf(SMLoc DirectiveLoc) {
1607 // Consume the identifier that was the .if directive
1608 Lex();
1609
1610 TheCondStack.push_back(TheCondState);
1611 TheCondState.TheCond = AsmCond::IfCond;
1612 if(TheCondState.Ignore) {
1613 EatToEndOfStatement();
1614 }
1615 else {
1616 int64_t ExprValue;
1617 if (ParseAbsoluteExpression(ExprValue))
1618 return true;
1619
1620 if (Lexer.isNot(AsmToken::EndOfStatement))
1621 return TokError("unexpected token in '.if' directive");
1622
1623 Lex();
1624
1625 TheCondState.CondMet = ExprValue;
1626 TheCondState.Ignore = !TheCondState.CondMet;
1627 }
1628
1629 return false;
1630}
1631
1632/// ParseDirectiveElseIf
1633/// ::= .elseif expression
1634bool AsmParser::ParseDirectiveElseIf(SMLoc DirectiveLoc) {
1635 if (TheCondState.TheCond != AsmCond::IfCond &&
1636 TheCondState.TheCond != AsmCond::ElseIfCond)
1637 Error(DirectiveLoc, "Encountered a .elseif that doesn't follow a .if or "
1638 " an .elseif");
1639 TheCondState.TheCond = AsmCond::ElseIfCond;
1640
1641 // Consume the identifier that was the .elseif directive
1642 Lex();
1643
1644 bool LastIgnoreState = false;
1645 if (!TheCondStack.empty())
1646 LastIgnoreState = TheCondStack.back().Ignore;
1647 if (LastIgnoreState || TheCondState.CondMet) {
1648 TheCondState.Ignore = true;
1649 EatToEndOfStatement();
1650 }
1651 else {
1652 int64_t ExprValue;
1653 if (ParseAbsoluteExpression(ExprValue))
1654 return true;
1655
1656 if (Lexer.isNot(AsmToken::EndOfStatement))
1657 return TokError("unexpected token in '.elseif' directive");
1658
1659 Lex();
1660 TheCondState.CondMet = ExprValue;
1661 TheCondState.Ignore = !TheCondState.CondMet;
1662 }
1663
1664 return false;
1665}
1666
1667/// ParseDirectiveElse
1668/// ::= .else
1669bool AsmParser::ParseDirectiveElse(SMLoc DirectiveLoc) {
1670 // Consume the identifier that was the .else directive
1671 Lex();
1672
1673 if (Lexer.isNot(AsmToken::EndOfStatement))
1674 return TokError("unexpected token in '.else' directive");
1675
1676 Lex();
1677
1678 if (TheCondState.TheCond != AsmCond::IfCond &&
1679 TheCondState.TheCond != AsmCond::ElseIfCond)
1680 Error(DirectiveLoc, "Encountered a .else that doesn't follow a .if or an "
1681 ".elseif");
1682 TheCondState.TheCond = AsmCond::ElseCond;
1683 bool LastIgnoreState = false;
1684 if (!TheCondStack.empty())
1685 LastIgnoreState = TheCondStack.back().Ignore;
1686 if (LastIgnoreState || TheCondState.CondMet)
1687 TheCondState.Ignore = true;
1688 else
1689 TheCondState.Ignore = false;
1690
1691 return false;
1692}
1693
1694/// ParseDirectiveEndIf
1695/// ::= .endif
1696bool AsmParser::ParseDirectiveEndIf(SMLoc DirectiveLoc) {
1697 // Consume the identifier that was the .endif directive
1698 Lex();
1699
1700 if (Lexer.isNot(AsmToken::EndOfStatement))
1701 return TokError("unexpected token in '.endif' directive");
1702
1703 Lex();
1704
1705 if ((TheCondState.TheCond == AsmCond::NoCond) ||
1706 TheCondStack.empty())
1707 Error(DirectiveLoc, "Encountered a .endif that doesn't follow a .if or "
1708 ".else");
1709 if (!TheCondStack.empty()) {
1710 TheCondState = TheCondStack.back();
1711 TheCondStack.pop_back();
1712 }
1713
1714 return false;
1715}
1716
1717/// ParseDirectiveFile
1718/// ::= .file [number] string
1719bool AsmParser::ParseDirectiveFile(StringRef, SMLoc DirectiveLoc) {
1720 // FIXME: I'm not sure what this is.
1721 int64_t FileNumber = -1;
1722 if (Lexer.is(AsmToken::Integer)) {
1723 FileNumber = getTok().getIntVal();
1724 Lex();
1725
1726 if (FileNumber < 1)
1727 return TokError("file number less than one");
1728 }
1729
1730 if (Lexer.isNot(AsmToken::String))
1731 return TokError("unexpected token in '.file' directive");
1732
1733 StringRef Filename = getTok().getString();
1734 Filename = Filename.substr(1, Filename.size()-2);
1735 Lex();
1736
1737 if (Lexer.isNot(AsmToken::EndOfStatement))
1738 return TokError("unexpected token in '.file' directive");
1739
1740 if (FileNumber == -1)
1741 Out.EmitFileDirective(Filename);
1742 else
1743 Out.EmitDwarfFileDirective(FileNumber, Filename);
1744
1745 return false;
1746}
1747
1748/// ParseDirectiveLine
1749/// ::= .line [number]
1750bool AsmParser::ParseDirectiveLine(StringRef, SMLoc DirectiveLoc) {
1751 if (Lexer.isNot(AsmToken::EndOfStatement)) {
1752 if (Lexer.isNot(AsmToken::Integer))
1753 return TokError("unexpected token in '.line' directive");
1754
1755 int64_t LineNumber = getTok().getIntVal();
1756 (void) LineNumber;
1757 Lex();
1758
1759 // FIXME: Do something with the .line.
1760 }
1761
1762 if (Lexer.isNot(AsmToken::EndOfStatement))
1763 return TokError("unexpected token in '.file' directive");
1764
1765 return false;
1766}
1767
1768
1769/// ParseDirectiveLoc
1770/// ::= .loc number [number [number]]
1771bool AsmParser::ParseDirectiveLoc(StringRef, SMLoc DirectiveLoc) {
1772 if (Lexer.isNot(AsmToken::Integer))
1773 return TokError("unexpected token in '.loc' directive");
1774
1775 // FIXME: What are these fields?
1776 int64_t FileNumber = getTok().getIntVal();
1777 (void) FileNumber;
1778 // FIXME: Validate file.
1779
1780 Lex();
1781 if (Lexer.isNot(AsmToken::EndOfStatement)) {
1782 if (Lexer.isNot(AsmToken::Integer))
1783 return TokError("unexpected token in '.loc' directive");
1784
1785 int64_t Param2 = getTok().getIntVal();
1786 (void) Param2;
1787 Lex();
1788
1789 if (Lexer.isNot(AsmToken::EndOfStatement)) {
1790 if (Lexer.isNot(AsmToken::Integer))
1791 return TokError("unexpected token in '.loc' directive");
1792
1793 int64_t Param3 = getTok().getIntVal();
1794 (void) Param3;
1795 Lex();
1796
1797 // FIXME: Do something with the .loc.
1798 }
1799 }
1800
1801 if (Lexer.isNot(AsmToken::EndOfStatement))
1802 return TokError("unexpected token in '.file' directive");
1803
1804 return false;
1805}
1806