diff options
Diffstat (limited to 'clang/lib')
-rw-r--r-- | clang/lib/Sema/Sema.cpp | 7 | ||||
-rw-r--r-- | clang/lib/Sema/Sema.h | 57 | ||||
-rw-r--r-- | clang/lib/Sema/SemaExpr.cpp | 49 | ||||
-rw-r--r-- | clang/lib/Sema/SemaExprCXX.cpp | 7 |
4 files changed, 80 insertions, 40 deletions
diff --git a/clang/lib/Sema/Sema.cpp b/clang/lib/Sema/Sema.cpp index 838fb6cbb00..f0812bfe7fd 100644 --- a/clang/lib/Sema/Sema.cpp +++ b/clang/lib/Sema/Sema.cpp @@ -352,7 +352,7 @@ Sema::Sema(Preprocessor &pp, ASTContext &ctxt, ASTConsumer &consumer, ExternalSource(0), CodeCompleter(CodeCompleter), CurContext(0), PreDeclaratorDC(0), CurBlock(0), PackContext(0), ParsingDeclDepth(0), IdResolver(pp.getLangOptions()), StdNamespace(0), StdBadAlloc(0), - GlobalNewDeleteDeclared(false), ExprEvalContext(PotentiallyEvaluated), + GlobalNewDeleteDeclared(false), CompleteTranslationUnit(CompleteTranslationUnit), NumSFINAEErrors(0), NonInstantiationEntries(0), CurrentInstantiationScope(0) @@ -363,6 +363,9 @@ Sema::Sema(Preprocessor &pp, ASTContext &ctxt, ASTConsumer &consumer, // Tell diagnostics how to render things from the AST library. PP.getDiagnostics().SetArgToStringFn(ConvertArgToStringFn, &Context); + + ExprEvalContexts.push_back( + ExpressionEvaluationContextRecord(PotentiallyEvaluated, 0)); } /// Retrieves the width and signedness of the given integer type, @@ -592,7 +595,7 @@ static void DiagnoseImpCast(Sema &S, Expr *E, QualType T, unsigned diag) { /// Implements -Wconversion. static void CheckImplicitConversion(Sema &S, Expr *E, QualType T) { // Don't diagnose in unevaluated contexts. - if (S.ExprEvalContext == Sema::Unevaluated) + if (S.ExprEvalContexts.back().Context == Sema::Unevaluated) return; // Don't diagnose for value-dependent expressions. diff --git a/clang/lib/Sema/Sema.h b/clang/lib/Sema/Sema.h index 084f720d4dd..5577cbd7d74 100644 --- a/clang/lib/Sema/Sema.h +++ b/clang/lib/Sema/Sema.h @@ -330,18 +330,49 @@ public: /// have been declared. bool GlobalNewDeleteDeclared; - /// The current expression evaluation context. - ExpressionEvaluationContext ExprEvalContext; - - typedef std::vector<std::pair<SourceLocation, Decl *> > + /// \brief The set of declarations that have been referenced within + /// a potentially evaluated expression. + typedef std::vector<std::pair<SourceLocation, Decl *> > PotentiallyReferencedDecls; - /// A stack of declarations, each element of which is a set of declarations - /// that will be marked as referenced if the corresponding potentially - /// potentially evaluated expression is potentially evaluated. Each element - /// in the stack corresponds to a PotentiallyPotentiallyEvaluated expression - /// evaluation context. - std::list<PotentiallyReferencedDecls> PotentiallyReferencedDeclStack; + /// \brief Data structure used to record current or nested + /// expression evaluation contexts. + struct ExpressionEvaluationContextRecord { + /// \brief The expression evaluation context. + ExpressionEvaluationContext Context; + + /// \brief The number of temporaries that were active when we + /// entered this expression evaluation context. + unsigned NumTemporaries; + + /// \brief The set of declarations referenced within a + /// potentially potentially-evaluated context. + /// + /// When leaving a potentially potentially-evaluated context, each + /// of these elements will be as referenced if the corresponding + /// potentially potentially evaluated expression is potentially + /// evaluated. + PotentiallyReferencedDecls *PotentiallyReferenced; + + ExpressionEvaluationContextRecord(ExpressionEvaluationContext Context, + unsigned NumTemporaries) + : Context(Context), NumTemporaries(NumTemporaries), + PotentiallyReferenced(0) { } + + void addReferencedDecl(SourceLocation Loc, Decl *Decl) { + if (!PotentiallyReferenced) + PotentiallyReferenced = new PotentiallyReferencedDecls; + PotentiallyReferenced->push_back(std::make_pair(Loc, Decl)); + } + + void Destroy() { + delete PotentiallyReferenced; + PotentiallyReferenced = 0; + } + }; + + /// A stack of expression evaluation contexts. + llvm::SmallVector<ExpressionEvaluationContextRecord, 8> ExprEvalContexts; /// \brief Whether the code handled by Sema should be considered a /// complete translation unit or not. @@ -1377,12 +1408,10 @@ public: const PartialDiagnostic &PD, bool Equality = false); - virtual ExpressionEvaluationContext + virtual void PushExpressionEvaluationContext(ExpressionEvaluationContext NewContext); - virtual void - PopExpressionEvaluationContext(ExpressionEvaluationContext OldContext, - ExpressionEvaluationContext NewContext); + virtual void PopExpressionEvaluationContext(); void MarkDeclarationReferenced(SourceLocation Loc, Decl *D); diff --git a/clang/lib/Sema/SemaExpr.cpp b/clang/lib/Sema/SemaExpr.cpp index 5479ce65fa8..f3a6765a6a2 100644 --- a/clang/lib/Sema/SemaExpr.cpp +++ b/clang/lib/Sema/SemaExpr.cpp @@ -4490,7 +4490,7 @@ QualType Sema::CheckShiftOperands(Expr *&lex, Expr *&rex, SourceLocation Loc, void Sema::CheckSignCompare(Expr *lex, Expr *rex, SourceLocation OpLoc, const PartialDiagnostic &PD, bool Equality) { // Don't warn if we're in an unevaluated context. - if (ExprEvalContext == Unevaluated) + if (ExprEvalContexts.back().Context == Unevaluated) return; QualType lt = lex->getType(), rt = rex->getType(); @@ -6378,34 +6378,41 @@ bool Sema::VerifyIntegerConstantExpression(const Expr *E, llvm::APSInt *Result){ return false; } -Sema::ExpressionEvaluationContext +void Sema::PushExpressionEvaluationContext(ExpressionEvaluationContext NewContext) { - // Introduce a new set of potentially referenced declarations to the stack. - if (NewContext == PotentiallyPotentiallyEvaluated) - PotentiallyReferencedDeclStack.push_back(PotentiallyReferencedDecls()); - - std::swap(ExprEvalContext, NewContext); - return NewContext; + ExprEvalContexts.push_back( + ExpressionEvaluationContextRecord(NewContext, ExprTemporaries.size())); } void -Sema::PopExpressionEvaluationContext(ExpressionEvaluationContext OldContext, - ExpressionEvaluationContext NewContext) { - ExprEvalContext = NewContext; +Sema::PopExpressionEvaluationContext() { + // Pop the current expression evaluation context off the stack. + ExpressionEvaluationContextRecord Rec = ExprEvalContexts.back(); + ExprEvalContexts.pop_back(); - if (OldContext == PotentiallyPotentiallyEvaluated) { + if (Rec.Context == PotentiallyPotentiallyEvaluated && + Rec.PotentiallyReferenced) { // Mark any remaining declarations in the current position of the stack // as "referenced". If they were not meant to be referenced, semantic // analysis would have eliminated them (e.g., in ActOnCXXTypeId). - PotentiallyReferencedDecls RemainingDecls; - RemainingDecls.swap(PotentiallyReferencedDeclStack.back()); - PotentiallyReferencedDeclStack.pop_back(); - - for (PotentiallyReferencedDecls::iterator I = RemainingDecls.begin(), - IEnd = RemainingDecls.end(); + for (PotentiallyReferencedDecls::iterator + I = Rec.PotentiallyReferenced->begin(), + IEnd = Rec.PotentiallyReferenced->end(); I != IEnd; ++I) MarkDeclarationReferenced(I->first, I->second); - } + } + + // When are coming out of an unevaluated context, clear out any + // temporaries that we may have created as part of the evaluation of + // the expression in that context: they aren't relevant because they + // will never be constructed. + if (Rec.Context == Unevaluated && + ExprTemporaries.size() > Rec.NumTemporaries) + ExprTemporaries.erase(ExprTemporaries.begin() + Rec.NumTemporaries, + ExprTemporaries.end()); + + // Destroy the popped expression evaluation record. + Rec.Destroy(); } /// \brief Note that the given declaration was referenced in the source code. @@ -6437,7 +6444,7 @@ void Sema::MarkDeclarationReferenced(SourceLocation Loc, Decl *D) { if (CurContext->isDependentContext()) return; - switch (ExprEvalContext) { + switch (ExprEvalContexts.back().Context) { case Unevaluated: // We are in an expression that is not potentially evaluated; do nothing. return; @@ -6451,7 +6458,7 @@ void Sema::MarkDeclarationReferenced(SourceLocation Loc, Decl *D) { // We are in an expression that may be potentially evaluated; queue this // declaration reference until we know whether the expression is // potentially evaluated. - PotentiallyReferencedDeclStack.back().push_back(std::make_pair(Loc, D)); + ExprEvalContexts.back().addReferencedDecl(Loc, D); return; } diff --git a/clang/lib/Sema/SemaExprCXX.cpp b/clang/lib/Sema/SemaExprCXX.cpp index 3b18b3a1ba9..af7a56fb7b0 100644 --- a/clang/lib/Sema/SemaExprCXX.cpp +++ b/clang/lib/Sema/SemaExprCXX.cpp @@ -63,10 +63,11 @@ Sema::ActOnCXXTypeid(SourceLocation OpLoc, SourceLocation LParenLoc, } } - // If this is an unevaluated operand, clear out the set of declaration - // references we have been computing. + // If this is an unevaluated operand, clear out the set of + // declaration references we have been computing and eliminate any + // temporaries introduced in its computation. if (isUnevaluatedOperand) - PotentiallyReferencedDeclStack.back().clear(); + ExprEvalContexts.back().Context = Unevaluated; } return Owned(new (Context) CXXTypeidExpr(isType, TyOrExpr, |