| //===--- SemaStmtAsm.cpp - Semantic Analysis for Asm Statements -----------===// |
| // |
| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| // See https://llvm.org/LICENSE.txt for license information. |
| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file implements semantic analysis for inline asm statements. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "clang/AST/ExprCXX.h" |
| #include "clang/AST/RecordLayout.h" |
| #include "clang/AST/TypeLoc.h" |
| #include "clang/Basic/TargetInfo.h" |
| #include "clang/Lex/Preprocessor.h" |
| #include "clang/Sema/Initialization.h" |
| #include "clang/Sema/Lookup.h" |
| #include "clang/Sema/Scope.h" |
| #include "clang/Sema/ScopeInfo.h" |
| #include "clang/Sema/SemaInternal.h" |
| #include "llvm/ADT/ArrayRef.h" |
| #include "llvm/ADT/StringSet.h" |
| #include "llvm/MC/MCParser/MCAsmParser.h" |
| using namespace clang; |
| using namespace sema; |
| |
| /// Remove the upper-level LValueToRValue cast from an expression. |
| static void removeLValueToRValueCast(Expr *E) { |
| Expr *Parent = E; |
| Expr *ExprUnderCast = nullptr; |
| SmallVector<Expr *, 8> ParentsToUpdate; |
| |
| while (true) { |
| ParentsToUpdate.push_back(Parent); |
| if (auto *ParenE = dyn_cast<ParenExpr>(Parent)) { |
| Parent = ParenE->getSubExpr(); |
| continue; |
| } |
| |
| Expr *Child = nullptr; |
| CastExpr *ParentCast = dyn_cast<CastExpr>(Parent); |
| if (ParentCast) |
| Child = ParentCast->getSubExpr(); |
| else |
| return; |
| |
| if (auto *CastE = dyn_cast<CastExpr>(Child)) |
| if (CastE->getCastKind() == CK_LValueToRValue) { |
| ExprUnderCast = CastE->getSubExpr(); |
| // LValueToRValue cast inside GCCAsmStmt requires an explicit cast. |
| ParentCast->setSubExpr(ExprUnderCast); |
| break; |
| } |
| Parent = Child; |
| } |
| |
| // Update parent expressions to have same ValueType as the underlying. |
| assert(ExprUnderCast && |
| "Should be reachable only if LValueToRValue cast was found!"); |
| auto ValueKind = ExprUnderCast->getValueKind(); |
| for (Expr *E : ParentsToUpdate) |
| E->setValueKind(ValueKind); |
| } |
| |
| /// Emit a warning about usage of "noop"-like casts for lvalues (GNU extension) |
| /// and fix the argument with removing LValueToRValue cast from the expression. |
| static void emitAndFixInvalidAsmCastLValue(const Expr *LVal, Expr *BadArgument, |
| Sema &S) { |
| if (!S.getLangOpts().HeinousExtensions) { |
| S.Diag(LVal->getBeginLoc(), diag::err_invalid_asm_cast_lvalue) |
| << BadArgument->getSourceRange(); |
| } else { |
| S.Diag(LVal->getBeginLoc(), diag::warn_invalid_asm_cast_lvalue) |
| << BadArgument->getSourceRange(); |
| } |
| removeLValueToRValueCast(BadArgument); |
| } |
| |
| /// CheckAsmLValue - GNU C has an extremely ugly extension whereby they silently |
| /// ignore "noop" casts in places where an lvalue is required by an inline asm. |
| /// We emulate this behavior when -fheinous-gnu-extensions is specified, but |
| /// provide a strong guidance to not use it. |
| /// |
| /// This method checks to see if the argument is an acceptable l-value and |
| /// returns false if it is a case we can handle. |
| static bool CheckAsmLValue(Expr *E, Sema &S) { |
| // Type dependent expressions will be checked during instantiation. |
| if (E->isTypeDependent()) |
| return false; |
| |
| if (E->isLValue()) |
| return false; // Cool, this is an lvalue. |
| |
| // Okay, this is not an lvalue, but perhaps it is the result of a cast that we |
| // are supposed to allow. |
| const Expr *E2 = E->IgnoreParenNoopCasts(S.Context); |
| if (E != E2 && E2->isLValue()) { |
| emitAndFixInvalidAsmCastLValue(E2, E, S); |
| // Accept, even if we emitted an error diagnostic. |
| return false; |
| } |
| |
| // None of the above, just randomly invalid non-lvalue. |
| return true; |
| } |
| |
| /// isOperandMentioned - Return true if the specified operand # is mentioned |
| /// anywhere in the decomposed asm string. |
| static bool |
| isOperandMentioned(unsigned OpNo, |
| ArrayRef<GCCAsmStmt::AsmStringPiece> AsmStrPieces) { |
| for (unsigned p = 0, e = AsmStrPieces.size(); p != e; ++p) { |
| const GCCAsmStmt::AsmStringPiece &Piece = AsmStrPieces[p]; |
| if (!Piece.isOperand()) |
| continue; |
| |
| // If this is a reference to the input and if the input was the smaller |
| // one, then we have to reject this asm. |
| if (Piece.getOperandNo() == OpNo) |
| return true; |
| } |
| return false; |
| } |
| |
| static bool CheckNakedParmReference(Expr *E, Sema &S) { |
| FunctionDecl *Func = dyn_cast<FunctionDecl>(S.CurContext); |
| if (!Func) |
| return false; |
| if (!Func->hasAttr<NakedAttr>()) |
| return false; |
| |
| SmallVector<Expr*, 4> WorkList; |
| WorkList.push_back(E); |
| while (WorkList.size()) { |
| Expr *E = WorkList.pop_back_val(); |
| if (isa<CXXThisExpr>(E)) { |
| S.Diag(E->getBeginLoc(), diag::err_asm_naked_this_ref); |
| S.Diag(Func->getAttr<NakedAttr>()->getLocation(), diag::note_attribute); |
| return true; |
| } |
| if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E)) { |
| if (isa<ParmVarDecl>(DRE->getDecl())) { |
| S.Diag(DRE->getBeginLoc(), diag::err_asm_naked_parm_ref); |
| S.Diag(Func->getAttr<NakedAttr>()->getLocation(), diag::note_attribute); |
| return true; |
| } |
| } |
| for (Stmt *Child : E->children()) { |
| if (Expr *E = dyn_cast_or_null<Expr>(Child)) |
| WorkList.push_back(E); |
| } |
| } |
| return false; |
| } |
| |
| /// Returns true if given expression is not compatible with inline |
| /// assembly's memory constraint; false otherwise. |
| static bool checkExprMemoryConstraintCompat(Sema &S, Expr *E, |
| TargetInfo::ConstraintInfo &Info, |
| bool is_input_expr) { |
| enum { |
| ExprBitfield = 0, |
| ExprVectorElt, |
| ExprGlobalRegVar, |
| ExprSafeType |
| } EType = ExprSafeType; |
| |
| // Bitfields, vector elements and global register variables are not |
| // compatible. |
| if (E->refersToBitField()) |
| EType = ExprBitfield; |
| else if (E->refersToVectorElement()) |
| EType = ExprVectorElt; |
| else if (E->refersToGlobalRegisterVar()) |
| EType = ExprGlobalRegVar; |
| |
| if (EType != ExprSafeType) { |
| S.Diag(E->getBeginLoc(), diag::err_asm_non_addr_value_in_memory_constraint) |
| << EType << is_input_expr << Info.getConstraintStr() |
| << E->getSourceRange(); |
| return true; |
| } |
| |
| return false; |
| } |
| |
| // Extracting the register name from the Expression value, |
| // if there is no register name to extract, returns "" |
| static StringRef extractRegisterName(const Expr *Expression, |
| const TargetInfo &Target) { |
| Expression = Expression->IgnoreImpCasts(); |
| if (const DeclRefExpr *AsmDeclRef = dyn_cast<DeclRefExpr>(Expression)) { |
| // Handle cases where the expression is a variable |
| const VarDecl *Variable = dyn_cast<VarDecl>(AsmDeclRef->getDecl()); |
| if (Variable && Variable->getStorageClass() == SC_Register) { |
| if (AsmLabelAttr *Attr = Variable->getAttr<AsmLabelAttr>()) |
| if (Target.isValidGCCRegisterName(Attr->getLabel())) |
| return Target.getNormalizedGCCRegisterName(Attr->getLabel(), true); |
| } |
| } |
| return ""; |
| } |
| |
| // Checks if there is a conflict between the input and output lists with the |
| // clobbers list. If there's a conflict, returns the location of the |
| // conflicted clobber, else returns nullptr |
| static SourceLocation |
| getClobberConflictLocation(MultiExprArg Exprs, StringLiteral **Constraints, |
| StringLiteral **Clobbers, int NumClobbers, |
| const TargetInfo &Target, ASTContext &Cont) { |
| llvm::StringSet<> InOutVars; |
| // Collect all the input and output registers from the extended asm |
| // statement in order to check for conflicts with the clobber list |
| for (unsigned int i = 0; i < Exprs.size(); ++i) { |
| StringRef Constraint = Constraints[i]->getString(); |
| StringRef InOutReg = Target.getConstraintRegister( |
| Constraint, extractRegisterName(Exprs[i], Target)); |
| if (InOutReg != "") |
| InOutVars.insert(InOutReg); |
| } |
| // Check for each item in the clobber list if it conflicts with the input |
| // or output |
| for (int i = 0; i < NumClobbers; ++i) { |
| StringRef Clobber = Clobbers[i]->getString(); |
| // We only check registers, therefore we don't check cc and memory |
| // clobbers |
| if (Clobber == "cc" || Clobber == "memory") |
| continue; |
| Clobber = Target.getNormalizedGCCRegisterName(Clobber, true); |
| // Go over the output's registers we collected |
| if (InOutVars.count(Clobber)) |
| return Clobbers[i]->getBeginLoc(); |
| } |
| return SourceLocation(); |
| } |
| |
| StmtResult Sema::ActOnGCCAsmStmt(SourceLocation AsmLoc, bool IsSimple, |
| bool IsVolatile, unsigned NumOutputs, |
| unsigned NumInputs, IdentifierInfo **Names, |
| MultiExprArg constraints, MultiExprArg Exprs, |
| Expr *asmString, MultiExprArg clobbers, |
| SourceLocation RParenLoc) { |
| unsigned NumClobbers = clobbers.size(); |
| StringLiteral **Constraints = |
| reinterpret_cast<StringLiteral**>(constraints.data()); |
| StringLiteral *AsmString = cast<StringLiteral>(asmString); |
| StringLiteral **Clobbers = reinterpret_cast<StringLiteral**>(clobbers.data()); |
| |
| SmallVector<TargetInfo::ConstraintInfo, 4> OutputConstraintInfos; |
| |
| // The parser verifies that there is a string literal here. |
| assert(AsmString->isAscii()); |
| |
| // If we're compiling CUDA file and function attributes indicate that it's not |
| // for this compilation side, skip all the checks. |
| if (!DeclAttrsMatchCUDAMode(getLangOpts(), getCurFunctionDecl())) { |
| GCCAsmStmt *NS = new (Context) GCCAsmStmt( |
| Context, AsmLoc, IsSimple, IsVolatile, NumOutputs, NumInputs, Names, |
| Constraints, Exprs.data(), AsmString, NumClobbers, Clobbers, RParenLoc); |
| return NS; |
| } |
| |
| for (unsigned i = 0; i != NumOutputs; i++) { |
| StringLiteral *Literal = Constraints[i]; |
| assert(Literal->isAscii()); |
| |
| StringRef OutputName; |
| if (Names[i]) |
| OutputName = Names[i]->getName(); |
| |
| TargetInfo::ConstraintInfo Info(Literal->getString(), OutputName); |
| if (!Context.getTargetInfo().validateOutputConstraint(Info)) |
| return StmtResult(targetDiag(Literal->getBeginLoc(), |
| diag::err_asm_invalid_output_constraint) |
| << Info.getConstraintStr()); |
| |
| ExprResult ER = CheckPlaceholderExpr(Exprs[i]); |
| if (ER.isInvalid()) |
| return StmtError(); |
| Exprs[i] = ER.get(); |
| |
| // Check that the output exprs are valid lvalues. |
| Expr *OutputExpr = Exprs[i]; |
| |
| // Referring to parameters is not allowed in naked functions. |
| if (CheckNakedParmReference(OutputExpr, *this)) |
| return StmtError(); |
| |
| // Check that the output expression is compatible with memory constraint. |
| if (Info.allowsMemory() && |
| checkExprMemoryConstraintCompat(*this, OutputExpr, Info, false)) |
| return StmtError(); |
| |
| OutputConstraintInfos.push_back(Info); |
| |
| // If this is dependent, just continue. |
| if (OutputExpr->isTypeDependent()) |
| continue; |
| |
| Expr::isModifiableLvalueResult IsLV = |
| OutputExpr->isModifiableLvalue(Context, /*Loc=*/nullptr); |
| switch (IsLV) { |
| case Expr::MLV_Valid: |
| // Cool, this is an lvalue. |
| break; |
| case Expr::MLV_ArrayType: |
| // This is OK too. |
| break; |
| case Expr::MLV_LValueCast: { |
| const Expr *LVal = OutputExpr->IgnoreParenNoopCasts(Context); |
| emitAndFixInvalidAsmCastLValue(LVal, OutputExpr, *this); |
| // Accept, even if we emitted an error diagnostic. |
| break; |
| } |
| case Expr::MLV_IncompleteType: |
| case Expr::MLV_IncompleteVoidType: |
| if (RequireCompleteType(OutputExpr->getBeginLoc(), Exprs[i]->getType(), |
| diag::err_dereference_incomplete_type)) |
| return StmtError(); |
| LLVM_FALLTHROUGH; |
| default: |
| return StmtError(Diag(OutputExpr->getBeginLoc(), |
| diag::err_asm_invalid_lvalue_in_output) |
| << OutputExpr->getSourceRange()); |
| } |
| |
| unsigned Size = Context.getTypeSize(OutputExpr->getType()); |
| if (!Context.getTargetInfo().validateOutputSize(Literal->getString(), Size)) |
| return StmtResult(targetDiag(OutputExpr->getBeginLoc(), |
| diag::err_asm_invalid_output_size) |
| << Info.getConstraintStr()); |
| } |
| |
| SmallVector<TargetInfo::ConstraintInfo, 4> InputConstraintInfos; |
| |
| for (unsigned i = NumOutputs, e = NumOutputs + NumInputs; i != e; i++) { |
| StringLiteral *Literal = Constraints[i]; |
| assert(Literal->isAscii()); |
| |
| StringRef InputName; |
| if (Names[i]) |
| InputName = Names[i]->getName(); |
| |
| TargetInfo::ConstraintInfo Info(Literal->getString(), InputName); |
| if (!Context.getTargetInfo().validateInputConstraint(OutputConstraintInfos, |
| Info)) { |
| return StmtResult(targetDiag(Literal->getBeginLoc(), |
| diag::err_asm_invalid_input_constraint) |
| << Info.getConstraintStr()); |
| } |
| |
| ExprResult ER = CheckPlaceholderExpr(Exprs[i]); |
| if (ER.isInvalid()) |
| return StmtError(); |
| Exprs[i] = ER.get(); |
| |
| Expr *InputExpr = Exprs[i]; |
| |
| // Referring to parameters is not allowed in naked functions. |
| if (CheckNakedParmReference(InputExpr, *this)) |
| return StmtError(); |
| |
| // Check that the input expression is compatible with memory constraint. |
| if (Info.allowsMemory() && |
| checkExprMemoryConstraintCompat(*this, InputExpr, Info, true)) |
| return StmtError(); |
| |
| // Only allow void types for memory constraints. |
| if (Info.allowsMemory() && !Info.allowsRegister()) { |
| if (CheckAsmLValue(InputExpr, *this)) |
| return StmtError(Diag(InputExpr->getBeginLoc(), |
| diag::err_asm_invalid_lvalue_in_input) |
| << Info.getConstraintStr() |
| << InputExpr->getSourceRange()); |
| } else if (Info.requiresImmediateConstant() && !Info.allowsRegister()) { |
| if (!InputExpr->isValueDependent()) { |
| Expr::EvalResult EVResult; |
| if (!InputExpr->EvaluateAsRValue(EVResult, Context, true)) |
| return StmtError( |
| Diag(InputExpr->getBeginLoc(), diag::err_asm_immediate_expected) |
| << Info.getConstraintStr() << InputExpr->getSourceRange()); |
| llvm::APSInt Result = EVResult.Val.getInt(); |
| if (!Info.isValidAsmImmediate(Result)) |
| return StmtError(Diag(InputExpr->getBeginLoc(), |
| diag::err_invalid_asm_value_for_constraint) |
| << Result.toString(10) << Info.getConstraintStr() |
| << InputExpr->getSourceRange()); |
| } |
| |
| } else { |
| ExprResult Result = DefaultFunctionArrayLvalueConversion(Exprs[i]); |
| if (Result.isInvalid()) |
| return StmtError(); |
| |
| Exprs[i] = Result.get(); |
| } |
| |
| if (Info.allowsRegister()) { |
| if (InputExpr->getType()->isVoidType()) { |
| return StmtError( |
| Diag(InputExpr->getBeginLoc(), diag::err_asm_invalid_type_in_input) |
| << InputExpr->getType() << Info.getConstraintStr() |
| << InputExpr->getSourceRange()); |
| } |
| } |
| |
| InputConstraintInfos.push_back(Info); |
| |
| const Type *Ty = Exprs[i]->getType().getTypePtr(); |
| if (Ty->isDependentType()) |
| continue; |
| |
| if (!Ty->isVoidType() || !Info.allowsMemory()) |
| if (RequireCompleteType(InputExpr->getBeginLoc(), Exprs[i]->getType(), |
| diag::err_dereference_incomplete_type)) |
| return StmtError(); |
| |
| unsigned Size = Context.getTypeSize(Ty); |
| if (!Context.getTargetInfo().validateInputSize(Literal->getString(), |
| Size)) |
| return StmtResult( |
| targetDiag(InputExpr->getBeginLoc(), diag::err_asm_invalid_input_size) |
| << Info.getConstraintStr()); |
| } |
| |
| // Check that the clobbers are valid. |
| for (unsigned i = 0; i != NumClobbers; i++) { |
| StringLiteral *Literal = Clobbers[i]; |
| assert(Literal->isAscii()); |
| |
| StringRef Clobber = Literal->getString(); |
| |
| if (!Context.getTargetInfo().isValidClobber(Clobber)) |
| return StmtResult(targetDiag(Literal->getBeginLoc(), |
| diag::err_asm_unknown_register_name) |
| << Clobber); |
| } |
| |
| GCCAsmStmt *NS = |
| new (Context) GCCAsmStmt(Context, AsmLoc, IsSimple, IsVolatile, NumOutputs, |
| NumInputs, Names, Constraints, Exprs.data(), |
| AsmString, NumClobbers, Clobbers, RParenLoc); |
| // Validate the asm string, ensuring it makes sense given the operands we |
| // have. |
| SmallVector<GCCAsmStmt::AsmStringPiece, 8> Pieces; |
| unsigned DiagOffs; |
| if (unsigned DiagID = NS->AnalyzeAsmString(Pieces, Context, DiagOffs)) |
| return StmtResult( |
| targetDiag(getLocationOfStringLiteralByte(AsmString, DiagOffs), DiagID) |
| << AsmString->getSourceRange()); |
| |
| // Validate constraints and modifiers. |
| for (unsigned i = 0, e = Pieces.size(); i != e; ++i) { |
| GCCAsmStmt::AsmStringPiece &Piece = Pieces[i]; |
| if (!Piece.isOperand()) continue; |
| |
| // Look for the correct constraint index. |
| unsigned ConstraintIdx = Piece.getOperandNo(); |
| unsigned NumOperands = NS->getNumOutputs() + NS->getNumInputs(); |
| |
| // Look for the (ConstraintIdx - NumOperands + 1)th constraint with |
| // modifier '+'. |
| if (ConstraintIdx >= NumOperands) { |
| unsigned I = 0, E = NS->getNumOutputs(); |
| |
| for (unsigned Cnt = ConstraintIdx - NumOperands; I != E; ++I) |
| if (OutputConstraintInfos[I].isReadWrite() && Cnt-- == 0) { |
| ConstraintIdx = I; |
| break; |
| } |
| |
| assert(I != E && "Invalid operand number should have been caught in " |
| " AnalyzeAsmString"); |
| } |
| |
| // Now that we have the right indexes go ahead and check. |
| StringLiteral *Literal = Constraints[ConstraintIdx]; |
| const Type *Ty = Exprs[ConstraintIdx]->getType().getTypePtr(); |
| if (Ty->isDependentType() || Ty->isIncompleteType()) |
| continue; |
| |
| unsigned Size = Context.getTypeSize(Ty); |
| std::string SuggestedModifier; |
| if (!Context.getTargetInfo().validateConstraintModifier( |
| Literal->getString(), Piece.getModifier(), Size, |
| SuggestedModifier)) { |
| targetDiag(Exprs[ConstraintIdx]->getBeginLoc(), |
| diag::warn_asm_mismatched_size_modifier); |
| |
| if (!SuggestedModifier.empty()) { |
| auto B = targetDiag(Piece.getRange().getBegin(), |
| diag::note_asm_missing_constraint_modifier) |
| << SuggestedModifier; |
| SuggestedModifier = "%" + SuggestedModifier + Piece.getString(); |
| B << FixItHint::CreateReplacement(Piece.getRange(), SuggestedModifier); |
| } |
| } |
| } |
| |
| // Validate tied input operands for type mismatches. |
| unsigned NumAlternatives = ~0U; |
| for (unsigned i = 0, e = OutputConstraintInfos.size(); i != e; ++i) { |
| TargetInfo::ConstraintInfo &Info = OutputConstraintInfos[i]; |
| StringRef ConstraintStr = Info.getConstraintStr(); |
| unsigned AltCount = ConstraintStr.count(',') + 1; |
| if (NumAlternatives == ~0U) |
| NumAlternatives = AltCount; |
| else if (NumAlternatives != AltCount) |
| return StmtResult( |
| targetDiag(NS->getOutputExpr(i)->getBeginLoc(), |
| diag::err_asm_unexpected_constraint_alternatives) |
| << NumAlternatives << AltCount); |
| } |
| SmallVector<size_t, 4> InputMatchedToOutput(OutputConstraintInfos.size(), |
| ~0U); |
| for (unsigned i = 0, e = InputConstraintInfos.size(); i != e; ++i) { |
| TargetInfo::ConstraintInfo &Info = InputConstraintInfos[i]; |
| StringRef ConstraintStr = Info.getConstraintStr(); |
| unsigned AltCount = ConstraintStr.count(',') + 1; |
| if (NumAlternatives == ~0U) |
| NumAlternatives = AltCount; |
| else if (NumAlternatives != AltCount) |
| return StmtResult( |
| targetDiag(NS->getInputExpr(i)->getBeginLoc(), |
| diag::err_asm_unexpected_constraint_alternatives) |
| << NumAlternatives << AltCount); |
| |
| // If this is a tied constraint, verify that the output and input have |
| // either exactly the same type, or that they are int/ptr operands with the |
| // same size (int/long, int*/long, are ok etc). |
| if (!Info.hasTiedOperand()) continue; |
| |
| unsigned TiedTo = Info.getTiedOperand(); |
| unsigned InputOpNo = i+NumOutputs; |
| Expr *OutputExpr = Exprs[TiedTo]; |
| Expr *InputExpr = Exprs[InputOpNo]; |
| |
| // Make sure no more than one input constraint matches each output. |
| assert(TiedTo < InputMatchedToOutput.size() && "TiedTo value out of range"); |
| if (InputMatchedToOutput[TiedTo] != ~0U) { |
| targetDiag(NS->getInputExpr(i)->getBeginLoc(), |
| diag::err_asm_input_duplicate_match) |
| << TiedTo; |
| return StmtResult( |
| targetDiag( |
| NS->getInputExpr(InputMatchedToOutput[TiedTo])->getBeginLoc(), |
| diag::note_asm_input_duplicate_first) |
| << TiedTo); |
| } |
| InputMatchedToOutput[TiedTo] = i; |
| |
| if (OutputExpr->isTypeDependent() || InputExpr->isTypeDependent()) |
| continue; |
| |
| QualType InTy = InputExpr->getType(); |
| QualType OutTy = OutputExpr->getType(); |
| if (Context.hasSameType(InTy, OutTy)) |
| continue; // All types can be tied to themselves. |
| |
| // Decide if the input and output are in the same domain (integer/ptr or |
| // floating point. |
| enum AsmDomain { |
| AD_Int, AD_FP, AD_Other |
| } InputDomain, OutputDomain; |
| |
| if (InTy->isIntegerType() || InTy->isPointerType()) |
| InputDomain = AD_Int; |
| else if (InTy->isRealFloatingType()) |
| InputDomain = AD_FP; |
| else |
| InputDomain = AD_Other; |
| |
| if (OutTy->isIntegerType() || OutTy->isPointerType()) |
| OutputDomain = AD_Int; |
| else if (OutTy->isRealFloatingType()) |
| OutputDomain = AD_FP; |
| else |
| OutputDomain = AD_Other; |
| |
| // They are ok if they are the same size and in the same domain. This |
| // allows tying things like: |
| // void* to int* |
| // void* to int if they are the same size. |
| // double to long double if they are the same size. |
| // |
| uint64_t OutSize = Context.getTypeSize(OutTy); |
| uint64_t InSize = Context.getTypeSize(InTy); |
| if (OutSize == InSize && InputDomain == OutputDomain && |
| InputDomain != AD_Other) |
| continue; |
| |
| // If the smaller input/output operand is not mentioned in the asm string, |
| // then we can promote the smaller one to a larger input and the asm string |
| // won't notice. |
| bool SmallerValueMentioned = false; |
| |
| // If this is a reference to the input and if the input was the smaller |
| // one, then we have to reject this asm. |
| if (isOperandMentioned(InputOpNo, Pieces)) { |
| // This is a use in the asm string of the smaller operand. Since we |
| // codegen this by promoting to a wider value, the asm will get printed |
| // "wrong". |
| SmallerValueMentioned |= InSize < OutSize; |
| } |
| if (isOperandMentioned(TiedTo, Pieces)) { |
| // If this is a reference to the output, and if the output is the larger |
| // value, then it's ok because we'll promote the input to the larger type. |
| SmallerValueMentioned |= OutSize < InSize; |
| } |
| |
| // If the smaller value wasn't mentioned in the asm string, and if the |
| // output was a register, just extend the shorter one to the size of the |
| // larger one. |
| if (!SmallerValueMentioned && InputDomain != AD_Other && |
| OutputConstraintInfos[TiedTo].allowsRegister()) |
| continue; |
| |
| // Either both of the operands were mentioned or the smaller one was |
| // mentioned. One more special case that we'll allow: if the tied input is |
| // integer, unmentioned, and is a constant, then we'll allow truncating it |
| // down to the size of the destination. |
| if (InputDomain == AD_Int && OutputDomain == AD_Int && |
| !isOperandMentioned(InputOpNo, Pieces) && |
| InputExpr->isEvaluatable(Context)) { |
| CastKind castKind = |
| (OutTy->isBooleanType() ? CK_IntegralToBoolean : CK_IntegralCast); |
| InputExpr = ImpCastExprToType(InputExpr, OutTy, castKind).get(); |
| Exprs[InputOpNo] = InputExpr; |
| NS->setInputExpr(i, InputExpr); |
| continue; |
| } |
| |
| return StmtResult(targetDiag(InputExpr->getBeginLoc(), |
| diag::err_asm_tying_incompatible_types) |
| << InTy << OutTy << OutputExpr->getSourceRange() |
| << InputExpr->getSourceRange()); |
| } |
| |
| // Check for conflicts between clobber list and input or output lists |
| SourceLocation ConstraintLoc = |
| getClobberConflictLocation(Exprs, Constraints, Clobbers, NumClobbers, |
| Context.getTargetInfo(), Context); |
| if (ConstraintLoc.isValid()) |
| return StmtResult( |
| targetDiag(ConstraintLoc, diag::error_inoutput_conflict_with_clobber)); |
| |
| return NS; |
| } |
| |
| void Sema::FillInlineAsmIdentifierInfo(Expr *Res, |
| llvm::InlineAsmIdentifierInfo &Info) { |
| QualType T = Res->getType(); |
| Expr::EvalResult Eval; |
| if (T->isFunctionType() || T->isDependentType()) |
| return Info.setLabel(Res); |
| if (Res->isRValue()) { |
| if (isa<clang::EnumType>(T) && Res->EvaluateAsRValue(Eval, Context)) |
| return Info.setEnum(Eval.Val.getInt().getSExtValue()); |
| return Info.setLabel(Res); |
| } |
| unsigned Size = Context.getTypeSizeInChars(T).getQuantity(); |
| unsigned Type = Size; |
| if (const auto *ATy = Context.getAsArrayType(T)) |
| Type = Context.getTypeSizeInChars(ATy->getElementType()).getQuantity(); |
| bool IsGlobalLV = false; |
| if (Res->EvaluateAsLValue(Eval, Context)) |
| IsGlobalLV = Eval.isGlobalLValue(); |
| Info.setVar(Res, IsGlobalLV, Size, Type); |
| } |
| |
| ExprResult Sema::LookupInlineAsmIdentifier(CXXScopeSpec &SS, |
| SourceLocation TemplateKWLoc, |
| UnqualifiedId &Id, |
| bool IsUnevaluatedContext) { |
| |
| if (IsUnevaluatedContext) |
| PushExpressionEvaluationContext( |
| ExpressionEvaluationContext::UnevaluatedAbstract, |
| ReuseLambdaContextDecl); |
| |
| ExprResult Result = ActOnIdExpression(getCurScope(), SS, TemplateKWLoc, Id, |
| /*trailing lparen*/ false, |
| /*is & operand*/ false, |
| /*CorrectionCandidateCallback=*/nullptr, |
| /*IsInlineAsmIdentifier=*/ true); |
| |
| if (IsUnevaluatedContext) |
| PopExpressionEvaluationContext(); |
| |
| if (!Result.isUsable()) return Result; |
| |
| Result = CheckPlaceholderExpr(Result.get()); |
| if (!Result.isUsable()) return Result; |
| |
| // Referring to parameters is not allowed in naked functions. |
| if (CheckNakedParmReference(Result.get(), *this)) |
| return ExprError(); |
| |
| QualType T = Result.get()->getType(); |
| |
| if (T->isDependentType()) { |
| return Result; |
| } |
| |
| // Any sort of function type is fine. |
| if (T->isFunctionType()) { |
| return Result; |
| } |
| |
| // Otherwise, it needs to be a complete type. |
| if (RequireCompleteExprType(Result.get(), diag::err_asm_incomplete_type)) { |
| return ExprError(); |
| } |
| |
| return Result; |
| } |
| |
| bool Sema::LookupInlineAsmField(StringRef Base, StringRef Member, |
| unsigned &Offset, SourceLocation AsmLoc) { |
| Offset = 0; |
| SmallVector<StringRef, 2> Members; |
| Member.split(Members, "."); |
| |
| NamedDecl *FoundDecl = nullptr; |
| |
| // MS InlineAsm uses 'this' as a base |
| if (getLangOpts().CPlusPlus && Base.equals("this")) { |
| if (const Type *PT = getCurrentThisType().getTypePtrOrNull()) |
| FoundDecl = PT->getPointeeType()->getAsTagDecl(); |
| } else { |
| LookupResult BaseResult(*this, &Context.Idents.get(Base), SourceLocation(), |
| LookupOrdinaryName); |
| if (LookupName(BaseResult, getCurScope()) && BaseResult.isSingleResult()) |
| FoundDecl = BaseResult.getFoundDecl(); |
| } |
| |
| if (!FoundDecl) |
| return true; |
| |
| for (StringRef NextMember : Members) { |
| const RecordType *RT = nullptr; |
| if (VarDecl *VD = dyn_cast<VarDecl>(FoundDecl)) |
| RT = VD->getType()->getAs<RecordType>(); |
| else if (TypedefNameDecl *TD = dyn_cast<TypedefNameDecl>(FoundDecl)) { |
| MarkAnyDeclReferenced(TD->getLocation(), TD, /*OdrUse=*/false); |
| // MS InlineAsm often uses struct pointer aliases as a base |
| QualType QT = TD->getUnderlyingType(); |
| if (const auto *PT = QT->getAs<PointerType>()) |
| QT = PT->getPointeeType(); |
| RT = QT->getAs<RecordType>(); |
| } else if (TypeDecl *TD = dyn_cast<TypeDecl>(FoundDecl)) |
| RT = TD->getTypeForDecl()->getAs<RecordType>(); |
| else if (FieldDecl *TD = dyn_cast<FieldDecl>(FoundDecl)) |
| RT = TD->getType()->getAs<RecordType>(); |
| if (!RT) |
| return true; |
| |
| if (RequireCompleteType(AsmLoc, QualType(RT, 0), |
| diag::err_asm_incomplete_type)) |
| return true; |
| |
| LookupResult FieldResult(*this, &Context.Idents.get(NextMember), |
| SourceLocation(), LookupMemberName); |
| |
| if (!LookupQualifiedName(FieldResult, RT->getDecl())) |
| return true; |
| |
| if (!FieldResult.isSingleResult()) |
| return true; |
| FoundDecl = FieldResult.getFoundDecl(); |
| |
| // FIXME: Handle IndirectFieldDecl? |
| FieldDecl *FD = dyn_cast<FieldDecl>(FoundDecl); |
| if (!FD) |
| return true; |
| |
| const ASTRecordLayout &RL = Context.getASTRecordLayout(RT->getDecl()); |
| unsigned i = FD->getFieldIndex(); |
| CharUnits Result = Context.toCharUnitsFromBits(RL.getFieldOffset(i)); |
| Offset += (unsigned)Result.getQuantity(); |
| } |
| |
| return false; |
| } |
| |
| ExprResult |
| Sema::LookupInlineAsmVarDeclField(Expr *E, StringRef Member, |
| SourceLocation AsmLoc) { |
| |
| QualType T = E->getType(); |
| if (T->isDependentType()) { |
| DeclarationNameInfo NameInfo; |
| NameInfo.setLoc(AsmLoc); |
| NameInfo.setName(&Context.Idents.get(Member)); |
| return CXXDependentScopeMemberExpr::Create( |
| Context, E, T, /*IsArrow=*/false, AsmLoc, NestedNameSpecifierLoc(), |
| SourceLocation(), |
| /*FirstQualifierInScope=*/nullptr, NameInfo, /*TemplateArgs=*/nullptr); |
| } |
| |
| const RecordType *RT = T->getAs<RecordType>(); |
| // FIXME: Diagnose this as field access into a scalar type. |
| if (!RT) |
| return ExprResult(); |
| |
| LookupResult FieldResult(*this, &Context.Idents.get(Member), AsmLoc, |
| LookupMemberName); |
| |
| if (!LookupQualifiedName(FieldResult, RT->getDecl())) |
| return ExprResult(); |
| |
| // Only normal and indirect field results will work. |
| ValueDecl *FD = dyn_cast<FieldDecl>(FieldResult.getFoundDecl()); |
| if (!FD) |
| FD = dyn_cast<IndirectFieldDecl>(FieldResult.getFoundDecl()); |
| if (!FD) |
| return ExprResult(); |
| |
| // Make an Expr to thread through OpDecl. |
| ExprResult Result = BuildMemberReferenceExpr( |
| E, E->getType(), AsmLoc, /*IsArrow=*/false, CXXScopeSpec(), |
| SourceLocation(), nullptr, FieldResult, nullptr, nullptr); |
| |
| return Result; |
| } |
| |
| StmtResult Sema::ActOnMSAsmStmt(SourceLocation AsmLoc, SourceLocation LBraceLoc, |
| ArrayRef<Token> AsmToks, |
| StringRef AsmString, |
| unsigned NumOutputs, unsigned NumInputs, |
| ArrayRef<StringRef> Constraints, |
| ArrayRef<StringRef> Clobbers, |
| ArrayRef<Expr*> Exprs, |
| SourceLocation EndLoc) { |
| bool IsSimple = (NumOutputs != 0 || NumInputs != 0); |
| setFunctionHasBranchProtectedScope(); |
| MSAsmStmt *NS = |
| new (Context) MSAsmStmt(Context, AsmLoc, LBraceLoc, IsSimple, |
| /*IsVolatile*/ true, AsmToks, NumOutputs, NumInputs, |
| Constraints, Exprs, AsmString, |
| Clobbers, EndLoc); |
| return NS; |
| } |
| |
| LabelDecl *Sema::GetOrCreateMSAsmLabel(StringRef ExternalLabelName, |
| SourceLocation Location, |
| bool AlwaysCreate) { |
| LabelDecl* Label = LookupOrCreateLabel(PP.getIdentifierInfo(ExternalLabelName), |
| Location); |
| |
| if (Label->isMSAsmLabel()) { |
| // If we have previously created this label implicitly, mark it as used. |
| Label->markUsed(Context); |
| } else { |
| // Otherwise, insert it, but only resolve it if we have seen the label itself. |
| std::string InternalName; |
| llvm::raw_string_ostream OS(InternalName); |
| // Create an internal name for the label. The name should not be a valid |
| // mangled name, and should be unique. We use a dot to make the name an |
| // invalid mangled name. We use LLVM's inline asm ${:uid} escape so that a |
| // unique label is generated each time this blob is emitted, even after |
| // inlining or LTO. |
| OS << "__MSASMLABEL_.${:uid}__"; |
| for (char C : ExternalLabelName) { |
| OS << C; |
| // We escape '$' in asm strings by replacing it with "$$" |
| if (C == '$') |
| OS << '$'; |
| } |
| Label->setMSAsmLabel(OS.str()); |
| } |
| if (AlwaysCreate) { |
| // The label might have been created implicitly from a previously encountered |
| // goto statement. So, for both newly created and looked up labels, we mark |
| // them as resolved. |
| Label->setMSAsmLabelResolved(); |
| } |
| // Adjust their location for being able to generate accurate diagnostics. |
| Label->setLocation(Location); |
| |
| return Label; |
| } |