1 //===---- ParseStmtAsm.cpp - Assembly Statement Parser --------------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file implements parsing for GCC and Microsoft inline assembly.
12 //===----------------------------------------------------------------------===//
14 #include "clang/Parse/Parser.h"
15 #include "clang/AST/ASTContext.h"
16 #include "clang/Basic/Diagnostic.h"
17 #include "clang/Basic/TargetInfo.h"
18 #include "clang/Parse/RAIIObjectsForParser.h"
19 #include "llvm/ADT/SmallString.h"
20 #include "llvm/ADT/StringExtras.h"
21 #include "llvm/MC/MCAsmInfo.h"
22 #include "llvm/MC/MCContext.h"
23 #include "llvm/MC/MCInstPrinter.h"
24 #include "llvm/MC/MCInstrInfo.h"
25 #include "llvm/MC/MCObjectFileInfo.h"
26 #include "llvm/MC/MCParser/MCAsmParser.h"
27 #include "llvm/MC/MCParser/MCTargetAsmParser.h"
28 #include "llvm/MC/MCRegisterInfo.h"
29 #include "llvm/MC/MCStreamer.h"
30 #include "llvm/MC/MCSubtargetInfo.h"
31 #include "llvm/MC/MCTargetOptions.h"
32 #include "llvm/Support/SourceMgr.h"
33 #include "llvm/Support/TargetRegistry.h"
34 #include "llvm/Support/TargetSelect.h"
35 using namespace clang;
38 class ClangAsmParserCallback : public llvm::MCAsmParserSemaCallback {
40 SourceLocation AsmLoc;
43 /// The tokens we streamed into AsmString and handed off to MC.
44 ArrayRef<Token> AsmToks;
46 /// The offset of each token in AsmToks within AsmString.
47 ArrayRef<unsigned> AsmTokOffsets;
50 ClangAsmParserCallback(Parser &P, SourceLocation Loc, StringRef AsmString,
51 ArrayRef<Token> Toks, ArrayRef<unsigned> Offsets)
52 : TheParser(P), AsmLoc(Loc), AsmString(AsmString), AsmToks(Toks),
53 AsmTokOffsets(Offsets) {
54 assert(AsmToks.size() == AsmTokOffsets.size());
57 void *LookupInlineAsmIdentifier(StringRef &LineBuf,
58 llvm::InlineAsmIdentifierInfo &Info,
59 bool IsUnevaluatedContext) override {
60 // Collect the desired tokens.
61 SmallVector<Token, 16> LineToks;
62 const Token *FirstOrigToken = nullptr;
63 findTokensForString(LineBuf, LineToks, FirstOrigToken);
65 unsigned NumConsumedToks;
66 ExprResult Result = TheParser.ParseMSAsmIdentifier(
67 LineToks, NumConsumedToks, &Info, IsUnevaluatedContext);
69 // If we consumed the entire line, tell MC that.
70 // Also do this if we consumed nothing as a way of reporting failure.
71 if (NumConsumedToks == 0 || NumConsumedToks == LineToks.size()) {
72 // By not modifying LineBuf, we're implicitly consuming it all.
74 // Otherwise, consume up to the original tokens.
76 assert(FirstOrigToken && "not using original tokens?");
78 // Since we're using original tokens, apply that offset.
79 assert(FirstOrigToken[NumConsumedToks].getLocation() ==
80 LineToks[NumConsumedToks].getLocation());
81 unsigned FirstIndex = FirstOrigToken - AsmToks.begin();
82 unsigned LastIndex = FirstIndex + NumConsumedToks - 1;
84 // The total length we've consumed is the relative offset
85 // of the last token we consumed plus its length.
86 unsigned TotalOffset =
87 (AsmTokOffsets[LastIndex] + AsmToks[LastIndex].getLength() -
88 AsmTokOffsets[FirstIndex]);
89 LineBuf = LineBuf.substr(0, TotalOffset);
92 // Initialize the "decl" with the lookup result.
93 Info.OpDecl = static_cast<void *>(Result.get());
97 StringRef LookupInlineAsmLabel(StringRef Identifier, llvm::SourceMgr &LSM,
99 bool Create) override {
100 SourceLocation Loc = translateLocation(LSM, Location);
102 TheParser.getActions().GetOrCreateMSAsmLabel(Identifier, Loc, Create);
103 return Label->getMSAsmLabel();
106 bool LookupInlineAsmField(StringRef Base, StringRef Member,
107 unsigned &Offset) override {
108 return TheParser.getActions().LookupInlineAsmField(Base, Member, Offset,
112 static void DiagHandlerCallback(const llvm::SMDiagnostic &D, void *Context) {
113 ((ClangAsmParserCallback *)Context)->handleDiagnostic(D);
117 /// Collect the appropriate tokens for the given string.
118 void findTokensForString(StringRef Str, SmallVectorImpl<Token> &TempToks,
119 const Token *&FirstOrigToken) const {
120 // For now, assert that the string we're working with is a substring
121 // of what we gave to MC. This lets us use the original tokens.
122 assert(!std::less<const char *>()(Str.begin(), AsmString.begin()) &&
123 !std::less<const char *>()(AsmString.end(), Str.end()));
125 // Try to find a token whose offset matches the first token.
126 unsigned FirstCharOffset = Str.begin() - AsmString.begin();
127 const unsigned *FirstTokOffset = std::lower_bound(
128 AsmTokOffsets.begin(), AsmTokOffsets.end(), FirstCharOffset);
130 // For now, assert that the start of the string exactly
131 // corresponds to the start of a token.
132 assert(*FirstTokOffset == FirstCharOffset);
134 // Use all the original tokens for this line. (We assume the
135 // end of the line corresponds cleanly to a token break.)
136 unsigned FirstTokIndex = FirstTokOffset - AsmTokOffsets.begin();
137 FirstOrigToken = &AsmToks[FirstTokIndex];
138 unsigned LastCharOffset = Str.end() - AsmString.begin();
139 for (unsigned i = FirstTokIndex, e = AsmTokOffsets.size(); i != e; ++i) {
140 if (AsmTokOffsets[i] >= LastCharOffset)
142 TempToks.push_back(AsmToks[i]);
146 SourceLocation translateLocation(const llvm::SourceMgr &LSM, llvm::SMLoc SMLoc) {
147 // Compute an offset into the inline asm buffer.
148 // FIXME: This isn't right if .macro is involved (but hopefully, no
149 // real-world code does that).
150 const llvm::MemoryBuffer *LBuf =
151 LSM.getMemoryBuffer(LSM.FindBufferContainingLoc(SMLoc));
152 unsigned Offset = SMLoc.getPointer() - LBuf->getBufferStart();
154 // Figure out which token that offset points into.
155 const unsigned *TokOffsetPtr =
156 std::lower_bound(AsmTokOffsets.begin(), AsmTokOffsets.end(), Offset);
157 unsigned TokIndex = TokOffsetPtr - AsmTokOffsets.begin();
158 unsigned TokOffset = *TokOffsetPtr;
160 // If we come up with an answer which seems sane, use it; otherwise,
161 // just point at the __asm keyword.
162 // FIXME: Assert the answer is sane once we handle .macro correctly.
163 SourceLocation Loc = AsmLoc;
164 if (TokIndex < AsmToks.size()) {
165 const Token &Tok = AsmToks[TokIndex];
166 Loc = Tok.getLocation();
167 Loc = Loc.getLocWithOffset(Offset - TokOffset);
172 void handleDiagnostic(const llvm::SMDiagnostic &D) {
173 const llvm::SourceMgr &LSM = *D.getSourceMgr();
174 SourceLocation Loc = translateLocation(LSM, D.getLoc());
175 TheParser.Diag(Loc, diag::err_inline_ms_asm_parsing) << D.getMessage();
180 /// Parse an identifier in an MS-style inline assembly block.
182 /// \param CastInfo - a void* so that we don't have to teach Parser.h
183 /// about the actual type.
184 ExprResult Parser::ParseMSAsmIdentifier(llvm::SmallVectorImpl<Token> &LineToks,
185 unsigned &NumLineToksConsumed,
187 bool IsUnevaluatedContext) {
188 llvm::InlineAsmIdentifierInfo &Info =
189 *(llvm::InlineAsmIdentifierInfo *)CastInfo;
191 // Push a fake token on the end so that we don't overrun the token
192 // stream. We use ';' because it expression-parsing should never
194 const tok::TokenKind EndOfStream = tok::semi;
195 Token EndOfStreamTok;
196 EndOfStreamTok.startToken();
197 EndOfStreamTok.setKind(EndOfStream);
198 LineToks.push_back(EndOfStreamTok);
200 // Also copy the current token over.
201 LineToks.push_back(Tok);
203 PP.EnterTokenStream(LineToks, /*DisableMacroExpansions*/ true);
205 // Clear the current token and advance to the first token in LineToks.
208 // Parse an optional scope-specifier if we're in C++.
210 if (getLangOpts().CPlusPlus) {
211 ParseOptionalCXXScopeSpecifier(SS, nullptr, /*EnteringContext=*/false);
214 // Require an identifier here.
215 SourceLocation TemplateKWLoc;
219 if (Tok.is(tok::kw_this)) {
220 Result = ParseCXXThis();
223 Invalid = ParseUnqualifiedId(SS,
224 /*EnteringContext=*/false,
225 /*AllowDestructorName=*/false,
226 /*AllowConstructorName=*/false,
227 /*AllowDeductionGuide=*/false,
228 /*ObjectType=*/nullptr, TemplateKWLoc, Id);
229 // Perform the lookup.
230 Result = Actions.LookupInlineAsmIdentifier(SS, TemplateKWLoc, Id, Info,
231 IsUnevaluatedContext);
233 // While the next two tokens are 'period' 'identifier', repeatedly parse it as
234 // a field access. We have to avoid consuming assembler directives that look
236 while (Result.isUsable() && Tok.is(tok::period)) {
237 Token IdTok = PP.LookAhead(0);
238 if (IdTok.isNot(tok::identifier))
240 ConsumeToken(); // Consume the period.
241 IdentifierInfo *Id = Tok.getIdentifierInfo();
242 ConsumeToken(); // Consume the identifier.
243 Result = Actions.LookupInlineAsmVarDeclField(Result.get(), Id->getName(),
244 Info, Tok.getLocation());
247 // Figure out how many tokens we are into LineToks.
248 unsigned LineIndex = 0;
249 if (Tok.is(EndOfStream)) {
250 LineIndex = LineToks.size() - 2;
252 while (LineToks[LineIndex].getLocation() != Tok.getLocation()) {
254 assert(LineIndex < LineToks.size() - 2); // we added two extra tokens
258 // If we've run into the poison token we inserted before, or there
259 // was a parsing error, then claim the entire line.
260 if (Invalid || Tok.is(EndOfStream)) {
261 NumLineToksConsumed = LineToks.size() - 2;
263 // Otherwise, claim up to the start of the next token.
264 NumLineToksConsumed = LineIndex;
267 // Finally, restore the old parsing state by consuming all the tokens we
268 // staged before, implicitly killing off the token-lexer we pushed.
269 for (unsigned i = 0, e = LineToks.size() - LineIndex - 2; i != e; ++i) {
272 assert(Tok.is(EndOfStream));
275 // Leave LineToks in its original state.
282 /// Turn a sequence of our tokens back into a string that we can hand
283 /// to the MC asm parser.
284 static bool buildMSAsmString(Preprocessor &PP, SourceLocation AsmLoc,
285 ArrayRef<Token> AsmToks,
286 SmallVectorImpl<unsigned> &TokOffsets,
287 SmallString<512> &Asm) {
288 assert(!AsmToks.empty() && "Didn't expect an empty AsmToks!");
290 // Is this the start of a new assembly statement?
291 bool isNewStatement = true;
293 for (unsigned i = 0, e = AsmToks.size(); i < e; ++i) {
294 const Token &Tok = AsmToks[i];
296 // Start each new statement with a newline and a tab.
297 if (!isNewStatement && (Tok.is(tok::kw_asm) || Tok.isAtStartOfLine())) {
299 isNewStatement = true;
302 // Preserve the existence of leading whitespace except at the
303 // start of a statement.
304 if (!isNewStatement && Tok.hasLeadingSpace())
307 // Remember the offset of this token.
308 TokOffsets.push_back(Asm.size());
310 // Don't actually write '__asm' into the assembly stream.
311 if (Tok.is(tok::kw_asm)) {
312 // Complain about __asm at the end of the stream.
314 PP.Diag(AsmLoc, diag::err_asm_empty);
321 // Append the spelling of the token.
322 SmallString<32> SpellingBuffer;
323 bool SpellingInvalid = false;
324 Asm += PP.getSpelling(Tok, SpellingBuffer, &SpellingInvalid);
325 assert(!SpellingInvalid && "spelling was invalid after correct parse?");
327 // We are no longer at the start of a statement.
328 isNewStatement = false;
331 // Ensure that the buffer is null-terminated.
335 assert(TokOffsets.size() == AsmToks.size());
339 /// isTypeQualifier - Return true if the current token could be the
340 /// start of a type-qualifier-list.
341 static bool isTypeQualifier(const Token &Tok) {
342 switch (Tok.getKind()) {
343 default: return false;
346 case tok::kw_volatile:
347 case tok::kw_restrict:
348 case tok::kw___private:
349 case tok::kw___local:
350 case tok::kw___global:
351 case tok::kw___constant:
352 case tok::kw___generic:
353 case tok::kw___read_only:
354 case tok::kw___read_write:
355 case tok::kw___write_only:
360 // Determine if this is a GCC-style asm statement.
361 static bool isGCCAsmStatement(const Token &TokAfterAsm) {
362 return TokAfterAsm.is(tok::l_paren) || TokAfterAsm.is(tok::kw_goto) ||
363 isTypeQualifier(TokAfterAsm);
366 /// ParseMicrosoftAsmStatement. When -fms-extensions/-fasm-blocks is enabled,
367 /// this routine is called to collect the tokens for an MS asm statement.
369 /// [MS] ms-asm-statement:
371 /// ms-asm-block ms-asm-statement
373 /// [MS] ms-asm-block:
374 /// '__asm' ms-asm-line '\n'
375 /// '__asm' '{' ms-asm-instruction-block[opt] '}' ';'[opt]
377 /// [MS] ms-asm-instruction-block
379 /// ms-asm-line '\n' ms-asm-instruction-block
381 StmtResult Parser::ParseMicrosoftAsmStatement(SourceLocation AsmLoc) {
382 SourceManager &SrcMgr = PP.getSourceManager();
383 SourceLocation EndLoc = AsmLoc;
384 SmallVector<Token, 4> AsmToks;
386 bool SingleLineMode = true;
387 unsigned BraceNesting = 0;
388 unsigned short savedBraceCount = BraceCount;
389 bool InAsmComment = false;
392 unsigned NumTokensRead = 0;
393 SmallVector<SourceLocation, 4> LBraceLocs;
394 bool SkippedStartOfLine = false;
396 if (Tok.is(tok::l_brace)) {
397 // Braced inline asm: consume the opening brace.
398 SingleLineMode = false;
400 EndLoc = ConsumeBrace();
401 LBraceLocs.push_back(EndLoc);
404 // Single-line inline asm; compute which line it is on.
405 std::pair<FileID, unsigned> ExpAsmLoc =
406 SrcMgr.getDecomposedExpansionLoc(EndLoc);
407 FID = ExpAsmLoc.first;
408 LineNo = SrcMgr.getLineNumber(FID, ExpAsmLoc.second);
409 LBraceLocs.push_back(SourceLocation());
412 SourceLocation TokLoc = Tok.getLocation();
414 // If we hit EOF, we're done, period.
418 if (!InAsmComment && Tok.is(tok::l_brace)) {
419 // Consume the opening brace.
420 SkippedStartOfLine = Tok.isAtStartOfLine();
421 AsmToks.push_back(Tok);
422 EndLoc = ConsumeBrace();
424 LBraceLocs.push_back(EndLoc);
425 TokLoc = Tok.getLocation();
428 } else if (!InAsmComment && Tok.is(tok::semi)) {
429 // A semicolon in an asm is the start of a comment.
431 if (!SingleLineMode) {
432 // Compute which line the comment is on.
433 std::pair<FileID, unsigned> ExpSemiLoc =
434 SrcMgr.getDecomposedExpansionLoc(TokLoc);
435 FID = ExpSemiLoc.first;
436 LineNo = SrcMgr.getLineNumber(FID, ExpSemiLoc.second);
438 } else if (SingleLineMode || InAsmComment) {
439 // If end-of-line is significant, check whether this token is on a
441 std::pair<FileID, unsigned> ExpLoc =
442 SrcMgr.getDecomposedExpansionLoc(TokLoc);
443 if (ExpLoc.first != FID ||
444 SrcMgr.getLineNumber(ExpLoc.first, ExpLoc.second) != LineNo) {
445 // If this is a single-line __asm, we're done, except if the next
446 // line is MS-style asm too, in which case we finish a comment
447 // if needed and then keep processing the next line as a single
449 bool isAsm = Tok.is(tok::kw_asm);
450 if (SingleLineMode && (!isAsm || isGCCAsmStatement(NextToken())))
452 // We're no longer in a comment.
453 InAsmComment = false;
455 // If this is a new __asm {} block we want to process it separately
456 // from the single-line __asm statements
457 if (PP.LookAhead(0).is(tok::l_brace))
459 LineNo = SrcMgr.getLineNumber(ExpLoc.first, ExpLoc.second);
460 SkippedStartOfLine = Tok.isAtStartOfLine();
461 } else if (Tok.is(tok::semi)) {
462 // A multi-line asm-statement, where next line is a comment
465 LineNo = SrcMgr.getLineNumber(FID, ExpLoc.second);
467 } else if (!InAsmComment && Tok.is(tok::r_brace)) {
468 // In MSVC mode, braces only participate in brace matching and
469 // separating the asm statements. This is an intentional
470 // departure from the Apple gcc behavior.
475 if (!InAsmComment && BraceNesting && Tok.is(tok::r_brace) &&
476 BraceCount == (savedBraceCount + BraceNesting)) {
477 // Consume the closing brace.
478 SkippedStartOfLine = Tok.isAtStartOfLine();
479 // Don't want to add the closing brace of the whole asm block
480 if (SingleLineMode || BraceNesting > 1) {
481 Tok.clearFlag(Token::LeadingSpace);
482 AsmToks.push_back(Tok);
484 EndLoc = ConsumeBrace();
486 // Finish if all of the opened braces in the inline asm section were
488 if (BraceNesting == 0 && !SingleLineMode)
491 LBraceLocs.pop_back();
492 TokLoc = Tok.getLocation();
498 // Consume the next token; make sure we don't modify the brace count etc.
499 // if we are in a comment.
504 // Set the token as the start of line if we skipped the original start
505 // of line token in case it was a nested brace.
506 if (SkippedStartOfLine)
507 Tok.setFlag(Token::StartOfLine);
508 AsmToks.push_back(Tok);
511 TokLoc = Tok.getLocation();
513 SkippedStartOfLine = false;
516 if (BraceNesting && BraceCount != savedBraceCount) {
517 // __asm without closing brace (this can happen at EOF).
518 for (unsigned i = 0; i < BraceNesting; ++i) {
519 Diag(Tok, diag::err_expected) << tok::r_brace;
520 Diag(LBraceLocs.back(), diag::note_matching) << tok::l_brace;
521 LBraceLocs.pop_back();
524 } else if (NumTokensRead == 0) {
526 Diag(Tok, diag::err_expected) << tok::l_brace;
530 // Okay, prepare to use MC to parse the assembly.
531 SmallVector<StringRef, 4> ConstraintRefs;
532 SmallVector<Expr *, 4> Exprs;
533 SmallVector<StringRef, 4> ClobberRefs;
535 // We need an actual supported target.
536 const llvm::Triple &TheTriple = Actions.Context.getTargetInfo().getTriple();
537 llvm::Triple::ArchType ArchTy = TheTriple.getArch();
538 const std::string &TT = TheTriple.getTriple();
539 const llvm::Target *TheTarget = nullptr;
540 bool UnsupportedArch =
541 (ArchTy != llvm::Triple::x86 && ArchTy != llvm::Triple::x86_64);
542 if (UnsupportedArch) {
543 Diag(AsmLoc, diag::err_msasm_unsupported_arch) << TheTriple.getArchName();
546 TheTarget = llvm::TargetRegistry::lookupTarget(TT, Error);
548 Diag(AsmLoc, diag::err_msasm_unable_to_create_target) << Error;
551 assert(!LBraceLocs.empty() && "Should have at least one location here");
553 // If we don't support assembly, or the assembly is empty, we don't
554 // need to instantiate the AsmParser, etc.
555 if (!TheTarget || AsmToks.empty()) {
556 return Actions.ActOnMSAsmStmt(AsmLoc, LBraceLocs[0], AsmToks, StringRef(),
557 /*NumOutputs*/ 0, /*NumInputs*/ 0,
558 ConstraintRefs, ClobberRefs, Exprs, EndLoc);
561 // Expand the tokens into a string buffer.
562 SmallString<512> AsmString;
563 SmallVector<unsigned, 8> TokOffsets;
564 if (buildMSAsmString(PP, AsmLoc, AsmToks, TokOffsets, AsmString))
567 TargetOptions TO = Actions.Context.getTargetInfo().getTargetOpts();
568 std::string FeaturesStr =
569 llvm::join(TO.Features.begin(), TO.Features.end(), ",");
571 std::unique_ptr<llvm::MCRegisterInfo> MRI(TheTarget->createMCRegInfo(TT));
572 std::unique_ptr<llvm::MCAsmInfo> MAI(TheTarget->createMCAsmInfo(*MRI, TT));
573 // Get the instruction descriptor.
574 std::unique_ptr<llvm::MCInstrInfo> MII(TheTarget->createMCInstrInfo());
575 std::unique_ptr<llvm::MCObjectFileInfo> MOFI(new llvm::MCObjectFileInfo());
576 std::unique_ptr<llvm::MCSubtargetInfo> STI(
577 TheTarget->createMCSubtargetInfo(TT, TO.CPU, FeaturesStr));
579 llvm::SourceMgr TempSrcMgr;
580 llvm::MCContext Ctx(MAI.get(), MRI.get(), MOFI.get(), &TempSrcMgr);
581 MOFI->InitMCObjectFileInfo(TheTriple, /*PIC*/ false, llvm::CodeModel::Default,
583 std::unique_ptr<llvm::MemoryBuffer> Buffer =
584 llvm::MemoryBuffer::getMemBuffer(AsmString, "<MS inline asm>");
586 // Tell SrcMgr about this buffer, which is what the parser will pick up.
587 TempSrcMgr.AddNewSourceBuffer(std::move(Buffer), llvm::SMLoc());
589 std::unique_ptr<llvm::MCStreamer> Str(createNullStreamer(Ctx));
590 std::unique_ptr<llvm::MCAsmParser> Parser(
591 createMCAsmParser(TempSrcMgr, Ctx, *Str.get(), *MAI));
593 // FIXME: init MCOptions from sanitizer flags here.
594 llvm::MCTargetOptions MCOptions;
595 std::unique_ptr<llvm::MCTargetAsmParser> TargetParser(
596 TheTarget->createMCAsmParser(*STI, *Parser, *MII, MCOptions));
598 std::unique_ptr<llvm::MCInstPrinter> IP(
599 TheTarget->createMCInstPrinter(llvm::Triple(TT), 1, *MAI, *MII, *MRI));
601 // Change to the Intel dialect.
602 Parser->setAssemblerDialect(1);
603 Parser->setTargetParser(*TargetParser.get());
604 Parser->setParsingInlineAsm(true);
605 TargetParser->setParsingInlineAsm(true);
607 ClangAsmParserCallback Callback(*this, AsmLoc, AsmString, AsmToks,
609 TargetParser->setSemaCallback(&Callback);
610 TempSrcMgr.setDiagHandler(ClangAsmParserCallback::DiagHandlerCallback,
615 std::string AsmStringIR;
616 SmallVector<std::pair<void *, bool>, 4> OpExprs;
617 SmallVector<std::string, 4> Constraints;
618 SmallVector<std::string, 4> Clobbers;
619 if (Parser->parseMSInlineAsm(AsmLoc.getPtrEncoding(), AsmStringIR, NumOutputs,
620 NumInputs, OpExprs, Constraints, Clobbers,
621 MII.get(), IP.get(), Callback))
624 // Filter out "fpsw" and "mxcsr". They aren't valid GCC asm clobber
625 // constraints. Clang always adds fpsr to the clobber list anyway.
626 llvm::erase_if(Clobbers, [](const std::string &C) {
627 return C == "fpsw" || C == "mxcsr";
630 // Build the vector of clobber StringRefs.
631 ClobberRefs.insert(ClobberRefs.end(), Clobbers.begin(), Clobbers.end());
633 // Recast the void pointers and build the vector of constraint StringRefs.
634 unsigned NumExprs = NumOutputs + NumInputs;
635 ConstraintRefs.resize(NumExprs);
636 Exprs.resize(NumExprs);
637 for (unsigned i = 0, e = NumExprs; i != e; ++i) {
638 Expr *OpExpr = static_cast<Expr *>(OpExprs[i].first);
642 // Need address of variable.
643 if (OpExprs[i].second)
645 Actions.BuildUnaryOp(getCurScope(), AsmLoc, UO_AddrOf, OpExpr).get();
647 ConstraintRefs[i] = StringRef(Constraints[i]);
651 // FIXME: We should be passing source locations for better diagnostics.
652 return Actions.ActOnMSAsmStmt(AsmLoc, LBraceLocs[0], AsmToks, AsmStringIR,
653 NumOutputs, NumInputs, ConstraintRefs,
654 ClobberRefs, Exprs, EndLoc);
657 /// ParseAsmStatement - Parse a GNU extended asm statement.
659 /// gnu-asm-statement
662 /// [GNU] gnu-asm-statement:
663 /// 'asm' type-qualifier[opt] '(' asm-argument ')' ';'
665 /// [GNU] asm-argument:
666 /// asm-string-literal
667 /// asm-string-literal ':' asm-operands[opt]
668 /// asm-string-literal ':' asm-operands[opt] ':' asm-operands[opt]
669 /// asm-string-literal ':' asm-operands[opt] ':' asm-operands[opt]
672 /// [GNU] asm-clobbers:
673 /// asm-string-literal
674 /// asm-clobbers ',' asm-string-literal
676 StmtResult Parser::ParseAsmStatement(bool &msAsm) {
677 assert(Tok.is(tok::kw_asm) && "Not an asm stmt");
678 SourceLocation AsmLoc = ConsumeToken();
680 if (getLangOpts().AsmBlocks && !isGCCAsmStatement(Tok)) {
682 return ParseMicrosoftAsmStatement(AsmLoc);
685 DeclSpec DS(AttrFactory);
686 SourceLocation Loc = Tok.getLocation();
687 ParseTypeQualifierListOpt(DS, AR_VendorAttributesParsed);
689 // GNU asms accept, but warn, about type-qualifiers other than volatile.
690 if (DS.getTypeQualifiers() & DeclSpec::TQ_const)
691 Diag(Loc, diag::warn_asm_qualifier_ignored) << "const";
692 if (DS.getTypeQualifiers() & DeclSpec::TQ_restrict)
693 Diag(Loc, diag::warn_asm_qualifier_ignored) << "restrict";
694 // FIXME: Once GCC supports _Atomic, check whether it permits it here.
695 if (DS.getTypeQualifiers() & DeclSpec::TQ_atomic)
696 Diag(Loc, diag::warn_asm_qualifier_ignored) << "_Atomic";
698 // Remember if this was a volatile asm.
699 bool isVolatile = DS.getTypeQualifiers() & DeclSpec::TQ_volatile;
701 // TODO: support "asm goto" constructs (PR#9295).
702 if (Tok.is(tok::kw_goto)) {
703 Diag(Tok, diag::err_asm_goto_not_supported_yet);
704 SkipUntil(tok::r_paren, StopAtSemi);
708 if (Tok.isNot(tok::l_paren)) {
709 Diag(Tok, diag::err_expected_lparen_after) << "asm";
710 SkipUntil(tok::r_paren, StopAtSemi);
713 BalancedDelimiterTracker T(*this, tok::l_paren);
716 ExprResult AsmString(ParseAsmStringLiteral());
718 // Check if GNU-style InlineAsm is disabled.
719 // Error on anything other than empty string.
720 if (!(getLangOpts().GNUAsm || AsmString.isInvalid())) {
721 const auto *SL = cast<StringLiteral>(AsmString.get());
722 if (!SL->getString().trim().empty())
723 Diag(Loc, diag::err_gnu_inline_asm_disabled);
726 if (AsmString.isInvalid()) {
727 // Consume up to and including the closing paren.
732 SmallVector<IdentifierInfo *, 4> Names;
733 ExprVector Constraints;
737 if (Tok.is(tok::r_paren)) {
738 // We have a simple asm expression like 'asm("foo")'.
740 return Actions.ActOnGCCAsmStmt(AsmLoc, /*isSimple*/ true, isVolatile,
741 /*NumOutputs*/ 0, /*NumInputs*/ 0, nullptr,
742 Constraints, Exprs, AsmString.get(),
743 Clobbers, T.getCloseLocation());
746 // Parse Outputs, if present.
747 bool AteExtraColon = false;
748 if (Tok.is(tok::colon) || Tok.is(tok::coloncolon)) {
749 // In C++ mode, parse "::" like ": :".
750 AteExtraColon = Tok.is(tok::coloncolon);
753 if (!AteExtraColon && ParseAsmOperandsOpt(Names, Constraints, Exprs))
757 unsigned NumOutputs = Names.size();
759 // Parse Inputs, if present.
760 if (AteExtraColon || Tok.is(tok::colon) || Tok.is(tok::coloncolon)) {
761 // In C++ mode, parse "::" like ": :".
763 AteExtraColon = false;
765 AteExtraColon = Tok.is(tok::coloncolon);
769 if (!AteExtraColon && ParseAsmOperandsOpt(Names, Constraints, Exprs))
773 assert(Names.size() == Constraints.size() &&
774 Constraints.size() == Exprs.size() && "Input operand size mismatch!");
776 unsigned NumInputs = Names.size() - NumOutputs;
778 // Parse the clobbers, if present.
779 if (AteExtraColon || Tok.is(tok::colon)) {
783 // Parse the asm-string list for clobbers if present.
784 if (Tok.isNot(tok::r_paren)) {
786 ExprResult Clobber(ParseAsmStringLiteral());
788 if (Clobber.isInvalid())
791 Clobbers.push_back(Clobber.get());
793 if (!TryConsumeToken(tok::comma))
800 return Actions.ActOnGCCAsmStmt(
801 AsmLoc, false, isVolatile, NumOutputs, NumInputs, Names.data(),
802 Constraints, Exprs, AsmString.get(), Clobbers, T.getCloseLocation());
805 /// ParseAsmOperands - Parse the asm-operands production as used by
806 /// asm-statement, assuming the leading ':' token was eaten.
808 /// [GNU] asm-operands:
810 /// asm-operands ',' asm-operand
812 /// [GNU] asm-operand:
813 /// asm-string-literal '(' expression ')'
814 /// '[' identifier ']' asm-string-literal '(' expression ')'
817 // FIXME: Avoid unnecessary std::string trashing.
818 bool Parser::ParseAsmOperandsOpt(SmallVectorImpl<IdentifierInfo *> &Names,
819 SmallVectorImpl<Expr *> &Constraints,
820 SmallVectorImpl<Expr *> &Exprs) {
821 // 'asm-operands' isn't present?
822 if (!isTokenStringLiteral() && Tok.isNot(tok::l_square))
826 // Read the [id] if present.
827 if (Tok.is(tok::l_square)) {
828 BalancedDelimiterTracker T(*this, tok::l_square);
831 if (Tok.isNot(tok::identifier)) {
832 Diag(Tok, diag::err_expected) << tok::identifier;
833 SkipUntil(tok::r_paren, StopAtSemi);
837 IdentifierInfo *II = Tok.getIdentifierInfo();
843 Names.push_back(nullptr);
845 ExprResult Constraint(ParseAsmStringLiteral());
846 if (Constraint.isInvalid()) {
847 SkipUntil(tok::r_paren, StopAtSemi);
850 Constraints.push_back(Constraint.get());
852 if (Tok.isNot(tok::l_paren)) {
853 Diag(Tok, diag::err_expected_lparen_after) << "asm operand";
854 SkipUntil(tok::r_paren, StopAtSemi);
858 // Read the parenthesized expression.
859 BalancedDelimiterTracker T(*this, tok::l_paren);
861 ExprResult Res = Actions.CorrectDelayedTyposInExpr(ParseExpression());
863 if (Res.isInvalid()) {
864 SkipUntil(tok::r_paren, StopAtSemi);
867 Exprs.push_back(Res.get());
868 // Eat the comma and continue parsing if it exists.
869 if (!TryConsumeToken(tok::comma))