1 //===--- SemaStmtAsm.cpp - Semantic Analysis for Asm Statements -----------===//
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 semantic analysis for inline asm statements.
12 //===----------------------------------------------------------------------===//
14 #include "clang/AST/ExprCXX.h"
15 #include "clang/AST/RecordLayout.h"
16 #include "clang/AST/TypeLoc.h"
17 #include "clang/Basic/TargetInfo.h"
18 #include "clang/Lex/Preprocessor.h"
19 #include "clang/Sema/Initialization.h"
20 #include "clang/Sema/Lookup.h"
21 #include "clang/Sema/Scope.h"
22 #include "clang/Sema/ScopeInfo.h"
23 #include "clang/Sema/SemaInternal.h"
24 #include "llvm/ADT/ArrayRef.h"
25 #include "llvm/ADT/StringSet.h"
26 #include "llvm/MC/MCParser/MCAsmParser.h"
27 using namespace clang;
30 /// CheckAsmLValue - GNU C has an extremely ugly extension whereby they silently
31 /// ignore "noop" casts in places where an lvalue is required by an inline asm.
32 /// We emulate this behavior when -fheinous-gnu-extensions is specified, but
33 /// provide a strong guidance to not use it.
35 /// This method checks to see if the argument is an acceptable l-value and
36 /// returns false if it is a case we can handle.
37 static bool CheckAsmLValue(const Expr *E, Sema &S) {
38 // Type dependent expressions will be checked during instantiation.
39 if (E->isTypeDependent())
43 return false; // Cool, this is an lvalue.
45 // Okay, this is not an lvalue, but perhaps it is the result of a cast that we
46 // are supposed to allow.
47 const Expr *E2 = E->IgnoreParenNoopCasts(S.Context);
48 if (E != E2 && E2->isLValue()) {
49 if (!S.getLangOpts().HeinousExtensions)
50 S.Diag(E2->getLocStart(), diag::err_invalid_asm_cast_lvalue)
51 << E->getSourceRange();
53 S.Diag(E2->getLocStart(), diag::warn_invalid_asm_cast_lvalue)
54 << E->getSourceRange();
55 // Accept, even if we emitted an error diagnostic.
59 // None of the above, just randomly invalid non-lvalue.
63 /// isOperandMentioned - Return true if the specified operand # is mentioned
64 /// anywhere in the decomposed asm string.
65 static bool isOperandMentioned(unsigned OpNo,
66 ArrayRef<GCCAsmStmt::AsmStringPiece> AsmStrPieces) {
67 for (unsigned p = 0, e = AsmStrPieces.size(); p != e; ++p) {
68 const GCCAsmStmt::AsmStringPiece &Piece = AsmStrPieces[p];
69 if (!Piece.isOperand()) continue;
71 // If this is a reference to the input and if the input was the smaller
72 // one, then we have to reject this asm.
73 if (Piece.getOperandNo() == OpNo)
79 static bool CheckNakedParmReference(Expr *E, Sema &S) {
80 FunctionDecl *Func = dyn_cast<FunctionDecl>(S.CurContext);
83 if (!Func->hasAttr<NakedAttr>())
86 SmallVector<Expr*, 4> WorkList;
87 WorkList.push_back(E);
88 while (WorkList.size()) {
89 Expr *E = WorkList.pop_back_val();
90 if (isa<CXXThisExpr>(E)) {
91 S.Diag(E->getLocStart(), diag::err_asm_naked_this_ref);
92 S.Diag(Func->getAttr<NakedAttr>()->getLocation(), diag::note_attribute);
95 if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E)) {
96 if (isa<ParmVarDecl>(DRE->getDecl())) {
97 S.Diag(DRE->getLocStart(), diag::err_asm_naked_parm_ref);
98 S.Diag(Func->getAttr<NakedAttr>()->getLocation(), diag::note_attribute);
102 for (Stmt *Child : E->children()) {
103 if (Expr *E = dyn_cast_or_null<Expr>(Child))
104 WorkList.push_back(E);
110 /// \brief Returns true if given expression is not compatible with inline
111 /// assembly's memory constraint; false otherwise.
112 static bool checkExprMemoryConstraintCompat(Sema &S, Expr *E,
113 TargetInfo::ConstraintInfo &Info,
114 bool is_input_expr) {
120 } EType = ExprSafeType;
122 // Bitfields, vector elements and global register variables are not
124 if (E->refersToBitField())
125 EType = ExprBitfield;
126 else if (E->refersToVectorElement())
127 EType = ExprVectorElt;
128 else if (E->refersToGlobalRegisterVar())
129 EType = ExprGlobalRegVar;
131 if (EType != ExprSafeType) {
132 S.Diag(E->getLocStart(), diag::err_asm_non_addr_value_in_memory_constraint)
133 << EType << is_input_expr << Info.getConstraintStr()
134 << E->getSourceRange();
141 // Extracting the register name from the Expression value,
142 // if there is no register name to extract, returns ""
143 static StringRef extractRegisterName(const Expr *Expression,
144 const TargetInfo &Target) {
145 Expression = Expression->IgnoreImpCasts();
146 if (const DeclRefExpr *AsmDeclRef = dyn_cast<DeclRefExpr>(Expression)) {
147 // Handle cases where the expression is a variable
148 const VarDecl *Variable = dyn_cast<VarDecl>(AsmDeclRef->getDecl());
149 if (Variable && Variable->getStorageClass() == SC_Register) {
150 if (AsmLabelAttr *Attr = Variable->getAttr<AsmLabelAttr>())
151 if (Target.isValidGCCRegisterName(Attr->getLabel()))
152 return Target.getNormalizedGCCRegisterName(Attr->getLabel(), true);
158 // Checks if there is a conflict between the input and output lists with the
159 // clobbers list. If there's a conflict, returns the location of the
160 // conflicted clobber, else returns nullptr
161 static SourceLocation
162 getClobberConflictLocation(MultiExprArg Exprs, StringLiteral **Constraints,
163 StringLiteral **Clobbers, int NumClobbers,
164 const TargetInfo &Target, ASTContext &Cont) {
165 llvm::StringSet<> InOutVars;
166 // Collect all the input and output registers from the extended asm
167 // statement in order to check for conflicts with the clobber list
168 for (unsigned int i = 0; i < Exprs.size(); ++i) {
169 StringRef Constraint = Constraints[i]->getString();
170 StringRef InOutReg = Target.getConstraintRegister(
171 Constraint, extractRegisterName(Exprs[i], Target));
173 InOutVars.insert(InOutReg);
175 // Check for each item in the clobber list if it conflicts with the input
177 for (int i = 0; i < NumClobbers; ++i) {
178 StringRef Clobber = Clobbers[i]->getString();
179 // We only check registers, therefore we don't check cc and memory
181 if (Clobber == "cc" || Clobber == "memory")
183 Clobber = Target.getNormalizedGCCRegisterName(Clobber, true);
184 // Go over the output's registers we collected
185 if (InOutVars.count(Clobber))
186 return Clobbers[i]->getLocStart();
188 return SourceLocation();
191 StmtResult Sema::ActOnGCCAsmStmt(SourceLocation AsmLoc, bool IsSimple,
192 bool IsVolatile, unsigned NumOutputs,
193 unsigned NumInputs, IdentifierInfo **Names,
194 MultiExprArg constraints, MultiExprArg Exprs,
195 Expr *asmString, MultiExprArg clobbers,
196 SourceLocation RParenLoc) {
197 unsigned NumClobbers = clobbers.size();
198 StringLiteral **Constraints =
199 reinterpret_cast<StringLiteral**>(constraints.data());
200 StringLiteral *AsmString = cast<StringLiteral>(asmString);
201 StringLiteral **Clobbers = reinterpret_cast<StringLiteral**>(clobbers.data());
203 SmallVector<TargetInfo::ConstraintInfo, 4> OutputConstraintInfos;
205 // The parser verifies that there is a string literal here.
206 assert(AsmString->isAscii());
208 // If we're compiling CUDA file and function attributes indicate that it's not
209 // for this compilation side, skip all the checks.
210 if (!DeclAttrsMatchCUDAMode(getLangOpts(), getCurFunctionDecl())) {
211 GCCAsmStmt *NS = new (Context) GCCAsmStmt(
212 Context, AsmLoc, IsSimple, IsVolatile, NumOutputs, NumInputs, Names,
213 Constraints, Exprs.data(), AsmString, NumClobbers, Clobbers, RParenLoc);
217 for (unsigned i = 0; i != NumOutputs; i++) {
218 StringLiteral *Literal = Constraints[i];
219 assert(Literal->isAscii());
221 StringRef OutputName;
223 OutputName = Names[i]->getName();
225 TargetInfo::ConstraintInfo Info(Literal->getString(), OutputName);
226 if (!Context.getTargetInfo().validateOutputConstraint(Info))
227 return StmtError(Diag(Literal->getLocStart(),
228 diag::err_asm_invalid_output_constraint)
229 << Info.getConstraintStr());
231 ExprResult ER = CheckPlaceholderExpr(Exprs[i]);
236 // Check that the output exprs are valid lvalues.
237 Expr *OutputExpr = Exprs[i];
239 // Referring to parameters is not allowed in naked functions.
240 if (CheckNakedParmReference(OutputExpr, *this))
243 // Check that the output expression is compatible with memory constraint.
244 if (Info.allowsMemory() &&
245 checkExprMemoryConstraintCompat(*this, OutputExpr, Info, false))
248 OutputConstraintInfos.push_back(Info);
250 // If this is dependent, just continue.
251 if (OutputExpr->isTypeDependent())
254 Expr::isModifiableLvalueResult IsLV =
255 OutputExpr->isModifiableLvalue(Context, /*Loc=*/nullptr);
257 case Expr::MLV_Valid:
258 // Cool, this is an lvalue.
260 case Expr::MLV_ArrayType:
263 case Expr::MLV_LValueCast: {
264 const Expr *LVal = OutputExpr->IgnoreParenNoopCasts(Context);
265 if (!getLangOpts().HeinousExtensions) {
266 Diag(LVal->getLocStart(), diag::err_invalid_asm_cast_lvalue)
267 << OutputExpr->getSourceRange();
269 Diag(LVal->getLocStart(), diag::warn_invalid_asm_cast_lvalue)
270 << OutputExpr->getSourceRange();
272 // Accept, even if we emitted an error diagnostic.
275 case Expr::MLV_IncompleteType:
276 case Expr::MLV_IncompleteVoidType:
277 if (RequireCompleteType(OutputExpr->getLocStart(), Exprs[i]->getType(),
278 diag::err_dereference_incomplete_type))
282 return StmtError(Diag(OutputExpr->getLocStart(),
283 diag::err_asm_invalid_lvalue_in_output)
284 << OutputExpr->getSourceRange());
287 unsigned Size = Context.getTypeSize(OutputExpr->getType());
288 if (!Context.getTargetInfo().validateOutputSize(Literal->getString(),
290 return StmtError(Diag(OutputExpr->getLocStart(),
291 diag::err_asm_invalid_output_size)
292 << Info.getConstraintStr());
295 SmallVector<TargetInfo::ConstraintInfo, 4> InputConstraintInfos;
297 for (unsigned i = NumOutputs, e = NumOutputs + NumInputs; i != e; i++) {
298 StringLiteral *Literal = Constraints[i];
299 assert(Literal->isAscii());
303 InputName = Names[i]->getName();
305 TargetInfo::ConstraintInfo Info(Literal->getString(), InputName);
306 if (!Context.getTargetInfo().validateInputConstraint(OutputConstraintInfos,
308 return StmtError(Diag(Literal->getLocStart(),
309 diag::err_asm_invalid_input_constraint)
310 << Info.getConstraintStr());
313 ExprResult ER = CheckPlaceholderExpr(Exprs[i]);
318 Expr *InputExpr = Exprs[i];
320 // Referring to parameters is not allowed in naked functions.
321 if (CheckNakedParmReference(InputExpr, *this))
324 // Check that the input expression is compatible with memory constraint.
325 if (Info.allowsMemory() &&
326 checkExprMemoryConstraintCompat(*this, InputExpr, Info, true))
329 // Only allow void types for memory constraints.
330 if (Info.allowsMemory() && !Info.allowsRegister()) {
331 if (CheckAsmLValue(InputExpr, *this))
332 return StmtError(Diag(InputExpr->getLocStart(),
333 diag::err_asm_invalid_lvalue_in_input)
334 << Info.getConstraintStr()
335 << InputExpr->getSourceRange());
336 } else if (Info.requiresImmediateConstant() && !Info.allowsRegister()) {
337 if (!InputExpr->isValueDependent()) {
339 if (!InputExpr->EvaluateAsInt(Result, Context))
341 Diag(InputExpr->getLocStart(), diag::err_asm_immediate_expected)
342 << Info.getConstraintStr() << InputExpr->getSourceRange());
343 if (!Info.isValidAsmImmediate(Result))
344 return StmtError(Diag(InputExpr->getLocStart(),
345 diag::err_invalid_asm_value_for_constraint)
346 << Result.toString(10) << Info.getConstraintStr()
347 << InputExpr->getSourceRange());
351 ExprResult Result = DefaultFunctionArrayLvalueConversion(Exprs[i]);
352 if (Result.isInvalid())
355 Exprs[i] = Result.get();
358 if (Info.allowsRegister()) {
359 if (InputExpr->getType()->isVoidType()) {
360 return StmtError(Diag(InputExpr->getLocStart(),
361 diag::err_asm_invalid_type_in_input)
362 << InputExpr->getType() << Info.getConstraintStr()
363 << InputExpr->getSourceRange());
367 InputConstraintInfos.push_back(Info);
369 const Type *Ty = Exprs[i]->getType().getTypePtr();
370 if (Ty->isDependentType())
373 if (!Ty->isVoidType() || !Info.allowsMemory())
374 if (RequireCompleteType(InputExpr->getLocStart(), Exprs[i]->getType(),
375 diag::err_dereference_incomplete_type))
378 unsigned Size = Context.getTypeSize(Ty);
379 if (!Context.getTargetInfo().validateInputSize(Literal->getString(),
381 return StmtError(Diag(InputExpr->getLocStart(),
382 diag::err_asm_invalid_input_size)
383 << Info.getConstraintStr());
386 // Check that the clobbers are valid.
387 for (unsigned i = 0; i != NumClobbers; i++) {
388 StringLiteral *Literal = Clobbers[i];
389 assert(Literal->isAscii());
391 StringRef Clobber = Literal->getString();
393 if (!Context.getTargetInfo().isValidClobber(Clobber))
394 return StmtError(Diag(Literal->getLocStart(),
395 diag::err_asm_unknown_register_name) << Clobber);
399 new (Context) GCCAsmStmt(Context, AsmLoc, IsSimple, IsVolatile, NumOutputs,
400 NumInputs, Names, Constraints, Exprs.data(),
401 AsmString, NumClobbers, Clobbers, RParenLoc);
402 // Validate the asm string, ensuring it makes sense given the operands we
404 SmallVector<GCCAsmStmt::AsmStringPiece, 8> Pieces;
406 if (unsigned DiagID = NS->AnalyzeAsmString(Pieces, Context, DiagOffs)) {
407 Diag(getLocationOfStringLiteralByte(AsmString, DiagOffs), DiagID)
408 << AsmString->getSourceRange();
412 // Validate constraints and modifiers.
413 for (unsigned i = 0, e = Pieces.size(); i != e; ++i) {
414 GCCAsmStmt::AsmStringPiece &Piece = Pieces[i];
415 if (!Piece.isOperand()) continue;
417 // Look for the correct constraint index.
418 unsigned ConstraintIdx = Piece.getOperandNo();
419 unsigned NumOperands = NS->getNumOutputs() + NS->getNumInputs();
421 // Look for the (ConstraintIdx - NumOperands + 1)th constraint with
423 if (ConstraintIdx >= NumOperands) {
424 unsigned I = 0, E = NS->getNumOutputs();
426 for (unsigned Cnt = ConstraintIdx - NumOperands; I != E; ++I)
427 if (OutputConstraintInfos[I].isReadWrite() && Cnt-- == 0) {
432 assert(I != E && "Invalid operand number should have been caught in "
433 " AnalyzeAsmString");
436 // Now that we have the right indexes go ahead and check.
437 StringLiteral *Literal = Constraints[ConstraintIdx];
438 const Type *Ty = Exprs[ConstraintIdx]->getType().getTypePtr();
439 if (Ty->isDependentType() || Ty->isIncompleteType())
442 unsigned Size = Context.getTypeSize(Ty);
443 std::string SuggestedModifier;
444 if (!Context.getTargetInfo().validateConstraintModifier(
445 Literal->getString(), Piece.getModifier(), Size,
446 SuggestedModifier)) {
447 Diag(Exprs[ConstraintIdx]->getLocStart(),
448 diag::warn_asm_mismatched_size_modifier);
450 if (!SuggestedModifier.empty()) {
451 auto B = Diag(Piece.getRange().getBegin(),
452 diag::note_asm_missing_constraint_modifier)
453 << SuggestedModifier;
454 SuggestedModifier = "%" + SuggestedModifier + Piece.getString();
455 B.AddFixItHint(FixItHint::CreateReplacement(Piece.getRange(),
461 // Validate tied input operands for type mismatches.
462 unsigned NumAlternatives = ~0U;
463 for (unsigned i = 0, e = OutputConstraintInfos.size(); i != e; ++i) {
464 TargetInfo::ConstraintInfo &Info = OutputConstraintInfos[i];
465 StringRef ConstraintStr = Info.getConstraintStr();
466 unsigned AltCount = ConstraintStr.count(',') + 1;
467 if (NumAlternatives == ~0U)
468 NumAlternatives = AltCount;
469 else if (NumAlternatives != AltCount)
470 return StmtError(Diag(NS->getOutputExpr(i)->getLocStart(),
471 diag::err_asm_unexpected_constraint_alternatives)
472 << NumAlternatives << AltCount);
474 SmallVector<size_t, 4> InputMatchedToOutput(OutputConstraintInfos.size(),
476 for (unsigned i = 0, e = InputConstraintInfos.size(); i != e; ++i) {
477 TargetInfo::ConstraintInfo &Info = InputConstraintInfos[i];
478 StringRef ConstraintStr = Info.getConstraintStr();
479 unsigned AltCount = ConstraintStr.count(',') + 1;
480 if (NumAlternatives == ~0U)
481 NumAlternatives = AltCount;
482 else if (NumAlternatives != AltCount)
483 return StmtError(Diag(NS->getInputExpr(i)->getLocStart(),
484 diag::err_asm_unexpected_constraint_alternatives)
485 << NumAlternatives << AltCount);
487 // If this is a tied constraint, verify that the output and input have
488 // either exactly the same type, or that they are int/ptr operands with the
489 // same size (int/long, int*/long, are ok etc).
490 if (!Info.hasTiedOperand()) continue;
492 unsigned TiedTo = Info.getTiedOperand();
493 unsigned InputOpNo = i+NumOutputs;
494 Expr *OutputExpr = Exprs[TiedTo];
495 Expr *InputExpr = Exprs[InputOpNo];
497 // Make sure no more than one input constraint matches each output.
498 assert(TiedTo < InputMatchedToOutput.size() && "TiedTo value out of range");
499 if (InputMatchedToOutput[TiedTo] != ~0U) {
500 Diag(NS->getInputExpr(i)->getLocStart(),
501 diag::err_asm_input_duplicate_match)
503 Diag(NS->getInputExpr(InputMatchedToOutput[TiedTo])->getLocStart(),
504 diag::note_asm_input_duplicate_first)
508 InputMatchedToOutput[TiedTo] = i;
510 if (OutputExpr->isTypeDependent() || InputExpr->isTypeDependent())
513 QualType InTy = InputExpr->getType();
514 QualType OutTy = OutputExpr->getType();
515 if (Context.hasSameType(InTy, OutTy))
516 continue; // All types can be tied to themselves.
518 // Decide if the input and output are in the same domain (integer/ptr or
521 AD_Int, AD_FP, AD_Other
522 } InputDomain, OutputDomain;
524 if (InTy->isIntegerType() || InTy->isPointerType())
525 InputDomain = AD_Int;
526 else if (InTy->isRealFloatingType())
529 InputDomain = AD_Other;
531 if (OutTy->isIntegerType() || OutTy->isPointerType())
532 OutputDomain = AD_Int;
533 else if (OutTy->isRealFloatingType())
534 OutputDomain = AD_FP;
536 OutputDomain = AD_Other;
538 // They are ok if they are the same size and in the same domain. This
539 // allows tying things like:
541 // void* to int if they are the same size.
542 // double to long double if they are the same size.
544 uint64_t OutSize = Context.getTypeSize(OutTy);
545 uint64_t InSize = Context.getTypeSize(InTy);
546 if (OutSize == InSize && InputDomain == OutputDomain &&
547 InputDomain != AD_Other)
550 // If the smaller input/output operand is not mentioned in the asm string,
551 // then we can promote the smaller one to a larger input and the asm string
553 bool SmallerValueMentioned = false;
555 // If this is a reference to the input and if the input was the smaller
556 // one, then we have to reject this asm.
557 if (isOperandMentioned(InputOpNo, Pieces)) {
558 // This is a use in the asm string of the smaller operand. Since we
559 // codegen this by promoting to a wider value, the asm will get printed
561 SmallerValueMentioned |= InSize < OutSize;
563 if (isOperandMentioned(TiedTo, Pieces)) {
564 // If this is a reference to the output, and if the output is the larger
565 // value, then it's ok because we'll promote the input to the larger type.
566 SmallerValueMentioned |= OutSize < InSize;
569 // If the smaller value wasn't mentioned in the asm string, and if the
570 // output was a register, just extend the shorter one to the size of the
572 if (!SmallerValueMentioned && InputDomain != AD_Other &&
573 OutputConstraintInfos[TiedTo].allowsRegister())
576 // Either both of the operands were mentioned or the smaller one was
577 // mentioned. One more special case that we'll allow: if the tied input is
578 // integer, unmentioned, and is a constant, then we'll allow truncating it
579 // down to the size of the destination.
580 if (InputDomain == AD_Int && OutputDomain == AD_Int &&
581 !isOperandMentioned(InputOpNo, Pieces) &&
582 InputExpr->isEvaluatable(Context)) {
584 (OutTy->isBooleanType() ? CK_IntegralToBoolean : CK_IntegralCast);
585 InputExpr = ImpCastExprToType(InputExpr, OutTy, castKind).get();
586 Exprs[InputOpNo] = InputExpr;
587 NS->setInputExpr(i, InputExpr);
591 Diag(InputExpr->getLocStart(),
592 diag::err_asm_tying_incompatible_types)
593 << InTy << OutTy << OutputExpr->getSourceRange()
594 << InputExpr->getSourceRange();
598 // Check for conflicts between clobber list and input or output lists
599 SourceLocation ConstraintLoc =
600 getClobberConflictLocation(Exprs, Constraints, Clobbers, NumClobbers,
601 Context.getTargetInfo(), Context);
602 if (ConstraintLoc.isValid())
603 return Diag(ConstraintLoc, diag::error_inoutput_conflict_with_clobber);
608 static void fillInlineAsmTypeInfo(const ASTContext &Context, QualType T,
609 llvm::InlineAsmIdentifierInfo &Info) {
610 // Compute the type size (and array length if applicable?).
611 Info.Type = Info.Size = Context.getTypeSizeInChars(T).getQuantity();
612 if (T->isArrayType()) {
613 const ArrayType *ATy = Context.getAsArrayType(T);
614 Info.Type = Context.getTypeSizeInChars(ATy->getElementType()).getQuantity();
615 Info.Length = Info.Size / Info.Type;
619 ExprResult Sema::LookupInlineAsmIdentifier(CXXScopeSpec &SS,
620 SourceLocation TemplateKWLoc,
622 llvm::InlineAsmIdentifierInfo &Info,
623 bool IsUnevaluatedContext) {
626 if (IsUnevaluatedContext)
627 PushExpressionEvaluationContext(
628 ExpressionEvaluationContext::UnevaluatedAbstract,
629 ReuseLambdaContextDecl);
631 ExprResult Result = ActOnIdExpression(getCurScope(), SS, TemplateKWLoc, Id,
632 /*trailing lparen*/ false,
633 /*is & operand*/ false,
634 /*CorrectionCandidateCallback=*/nullptr,
635 /*IsInlineAsmIdentifier=*/ true);
637 if (IsUnevaluatedContext)
638 PopExpressionEvaluationContext();
640 if (!Result.isUsable()) return Result;
642 Result = CheckPlaceholderExpr(Result.get());
643 if (!Result.isUsable()) return Result;
645 // Referring to parameters is not allowed in naked functions.
646 if (CheckNakedParmReference(Result.get(), *this))
649 QualType T = Result.get()->getType();
651 if (T->isDependentType()) {
655 // Any sort of function type is fine.
656 if (T->isFunctionType()) {
660 // Otherwise, it needs to be a complete type.
661 if (RequireCompleteExprType(Result.get(), diag::err_asm_incomplete_type)) {
665 fillInlineAsmTypeInfo(Context, T, Info);
667 // We can work with the expression as long as it's not an r-value.
668 if (!Result.get()->isRValue())
669 Info.IsVarDecl = true;
674 bool Sema::LookupInlineAsmField(StringRef Base, StringRef Member,
675 unsigned &Offset, SourceLocation AsmLoc) {
677 SmallVector<StringRef, 2> Members;
678 Member.split(Members, ".");
680 LookupResult BaseResult(*this, &Context.Idents.get(Base), SourceLocation(),
683 if (!LookupName(BaseResult, getCurScope()))
686 if(!BaseResult.isSingleResult())
688 NamedDecl *FoundDecl = BaseResult.getFoundDecl();
689 for (StringRef NextMember : Members) {
690 const RecordType *RT = nullptr;
691 if (VarDecl *VD = dyn_cast<VarDecl>(FoundDecl))
692 RT = VD->getType()->getAs<RecordType>();
693 else if (TypedefNameDecl *TD = dyn_cast<TypedefNameDecl>(FoundDecl)) {
694 MarkAnyDeclReferenced(TD->getLocation(), TD, /*OdrUse=*/false);
695 RT = TD->getUnderlyingType()->getAs<RecordType>();
696 } else if (TypeDecl *TD = dyn_cast<TypeDecl>(FoundDecl))
697 RT = TD->getTypeForDecl()->getAs<RecordType>();
698 else if (FieldDecl *TD = dyn_cast<FieldDecl>(FoundDecl))
699 RT = TD->getType()->getAs<RecordType>();
703 if (RequireCompleteType(AsmLoc, QualType(RT, 0),
704 diag::err_asm_incomplete_type))
707 LookupResult FieldResult(*this, &Context.Idents.get(NextMember),
708 SourceLocation(), LookupMemberName);
710 if (!LookupQualifiedName(FieldResult, RT->getDecl()))
713 if (!FieldResult.isSingleResult())
715 FoundDecl = FieldResult.getFoundDecl();
717 // FIXME: Handle IndirectFieldDecl?
718 FieldDecl *FD = dyn_cast<FieldDecl>(FoundDecl);
722 const ASTRecordLayout &RL = Context.getASTRecordLayout(RT->getDecl());
723 unsigned i = FD->getFieldIndex();
724 CharUnits Result = Context.toCharUnitsFromBits(RL.getFieldOffset(i));
725 Offset += (unsigned)Result.getQuantity();
732 Sema::LookupInlineAsmVarDeclField(Expr *E, StringRef Member,
733 llvm::InlineAsmIdentifierInfo &Info,
734 SourceLocation AsmLoc) {
737 QualType T = E->getType();
738 if (T->isDependentType()) {
739 DeclarationNameInfo NameInfo;
740 NameInfo.setLoc(AsmLoc);
741 NameInfo.setName(&Context.Idents.get(Member));
742 return CXXDependentScopeMemberExpr::Create(
743 Context, E, T, /*IsArrow=*/false, AsmLoc, NestedNameSpecifierLoc(),
745 /*FirstQualifierInScope=*/nullptr, NameInfo, /*TemplateArgs=*/nullptr);
748 const RecordType *RT = T->getAs<RecordType>();
749 // FIXME: Diagnose this as field access into a scalar type.
753 LookupResult FieldResult(*this, &Context.Idents.get(Member), AsmLoc,
756 if (!LookupQualifiedName(FieldResult, RT->getDecl()))
759 // Only normal and indirect field results will work.
760 ValueDecl *FD = dyn_cast<FieldDecl>(FieldResult.getFoundDecl());
762 FD = dyn_cast<IndirectFieldDecl>(FieldResult.getFoundDecl());
766 // Make an Expr to thread through OpDecl.
767 ExprResult Result = BuildMemberReferenceExpr(
768 E, E->getType(), AsmLoc, /*IsArrow=*/false, CXXScopeSpec(),
769 SourceLocation(), nullptr, FieldResult, nullptr, nullptr);
770 if (Result.isInvalid())
772 Info.OpDecl = Result.get();
774 fillInlineAsmTypeInfo(Context, Result.get()->getType(), Info);
776 // Fields are "variables" as far as inline assembly is concerned.
777 Info.IsVarDecl = true;
782 StmtResult Sema::ActOnMSAsmStmt(SourceLocation AsmLoc, SourceLocation LBraceLoc,
783 ArrayRef<Token> AsmToks,
785 unsigned NumOutputs, unsigned NumInputs,
786 ArrayRef<StringRef> Constraints,
787 ArrayRef<StringRef> Clobbers,
788 ArrayRef<Expr*> Exprs,
789 SourceLocation EndLoc) {
790 bool IsSimple = (NumOutputs != 0 || NumInputs != 0);
791 getCurFunction()->setHasBranchProtectedScope();
793 new (Context) MSAsmStmt(Context, AsmLoc, LBraceLoc, IsSimple,
794 /*IsVolatile*/ true, AsmToks, NumOutputs, NumInputs,
795 Constraints, Exprs, AsmString,
800 LabelDecl *Sema::GetOrCreateMSAsmLabel(StringRef ExternalLabelName,
801 SourceLocation Location,
803 LabelDecl* Label = LookupOrCreateLabel(PP.getIdentifierInfo(ExternalLabelName),
806 if (Label->isMSAsmLabel()) {
807 // If we have previously created this label implicitly, mark it as used.
808 Label->markUsed(Context);
810 // Otherwise, insert it, but only resolve it if we have seen the label itself.
811 std::string InternalName;
812 llvm::raw_string_ostream OS(InternalName);
813 // Create an internal name for the label. The name should not be a valid
814 // mangled name, and should be unique. We use a dot to make the name an
815 // invalid mangled name. We use LLVM's inline asm ${:uid} escape so that a
816 // unique label is generated each time this blob is emitted, even after
818 OS << "__MSASMLABEL_.${:uid}__";
819 for (char C : ExternalLabelName) {
821 // We escape '$' in asm strings by replacing it with "$$"
825 Label->setMSAsmLabel(OS.str());
828 // The label might have been created implicitly from a previously encountered
829 // goto statement. So, for both newly created and looked up labels, we mark
831 Label->setMSAsmLabelResolved();
833 // Adjust their location for being able to generate accurate diagnostics.
834 Label->setLocation(Location);