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-rw-r--r--lib/AST/ExprConstant.cpp141
1 files changed, 134 insertions, 7 deletions
diff --git a/lib/AST/ExprConstant.cpp b/lib/AST/ExprConstant.cpp
index 94d2299..7862c57 100644
--- a/lib/AST/ExprConstant.cpp
+++ b/lib/AST/ExprConstant.cpp
@@ -58,7 +58,8 @@ struct EvalInfo {
static bool EvaluateLValue(const Expr *E, APValue &Result, EvalInfo &Info);
static bool EvaluatePointer(const Expr *E, APValue &Result, EvalInfo &Info);
static bool EvaluateInteger(const Expr *E, APSInt &Result, EvalInfo &Info);
-static bool EvaluateIntegerOrLValue(const Expr *E, APValue &Result, EvalInfo &Info);
+static bool EvaluateIntegerOrLValue(const Expr *E, APValue &Result,
+ EvalInfo &Info);
static bool EvaluateFloat(const Expr *E, APFloat &Result, EvalInfo &Info);
static bool EvaluateComplex(const Expr *E, APValue &Result, EvalInfo &Info);
@@ -151,6 +152,67 @@ static APFloat HandleIntToFloatCast(QualType DestType, QualType SrcType,
return Result;
}
+namespace {
+class VISIBILITY_HIDDEN HasSideEffect
+ : public StmtVisitor<HasSideEffect, bool> {
+ EvalInfo &Info;
+public:
+
+ HasSideEffect(EvalInfo &info) : Info(info) {}
+
+ // Unhandled nodes conservatively default to having side effects.
+ bool VisitStmt(Stmt *S) {
+ return true;
+ }
+
+ bool VisitParenExpr(ParenExpr *E) { return Visit(E->getSubExpr()); }
+ bool VisitDeclRefExpr(DeclRefExpr *E) {
+ if (Info.Ctx.getCanonicalType(E->getType()).isVolatileQualified())
+ return true;
+ return false;
+ }
+ // We don't want to evaluate BlockExprs multiple times, as they generate
+ // a ton of code.
+ bool VisitBlockExpr(BlockExpr *E) { return true; }
+ bool VisitPredefinedExpr(PredefinedExpr *E) { return false; }
+ bool VisitCompoundLiteralExpr(CompoundLiteralExpr *E)
+ { return Visit(E->getInitializer()); }
+ bool VisitMemberExpr(MemberExpr *E) { return Visit(E->getBase()); }
+ bool VisitIntegerLiteral(IntegerLiteral *E) { return false; }
+ bool VisitFloatingLiteral(FloatingLiteral *E) { return false; }
+ bool VisitStringLiteral(StringLiteral *E) { return false; }
+ bool VisitCharacterLiteral(CharacterLiteral *E) { return false; }
+ bool VisitSizeOfAlignOfExpr(SizeOfAlignOfExpr *E) { return false; }
+ bool VisitArraySubscriptExpr(ArraySubscriptExpr *E)
+ { return Visit(E->getLHS()) || Visit(E->getRHS()); }
+ bool VisitChooseExpr(ChooseExpr *E)
+ { return Visit(E->getChosenSubExpr(Info.Ctx)); }
+ bool VisitCastExpr(CastExpr *E) { return Visit(E->getSubExpr()); }
+ bool VisitBinAssign(BinaryOperator *E) { return true; }
+ bool VisitCompoundAssignOperator(BinaryOperator *E) { return true; }
+ bool VisitBinaryOperator(BinaryOperator *E)
+ { return Visit(E->getLHS()) || Visit(E->getRHS()); }
+ bool VisitUnaryPreInc(UnaryOperator *E) { return true; }
+ bool VisitUnaryPostInc(UnaryOperator *E) { return true; }
+ bool VisitUnaryPreDec(UnaryOperator *E) { return true; }
+ bool VisitUnaryPostDec(UnaryOperator *E) { return true; }
+ bool VisitUnaryDeref(UnaryOperator *E) {
+ if (Info.Ctx.getCanonicalType(E->getType()).isVolatileQualified())
+ return true;
+ return Visit(E->getSubExpr());
+ }
+ bool VisitUnaryOperator(UnaryOperator *E) { return Visit(E->getSubExpr()); }
+};
+
+bool HasSideEffects(const Expr* E, ASTContext &Ctx) {
+ Expr::EvalResult Result;
+ EvalInfo Info(Ctx, Result);
+
+ return HasSideEffect(Info).Visit(const_cast<Expr*>(E));
+}
+
+} // end anonymous namespace
+
//===----------------------------------------------------------------------===//
// LValue Evaluation
//===----------------------------------------------------------------------===//
@@ -208,8 +270,9 @@ APValue LValueExprEvaluator::VisitDeclRefExpr(DeclRefExpr *E) {
if (!VD->getType()->isReferenceType())
return APValue(E, 0);
// FIXME: Check whether VD might be overridden!
- if (VD->getInit())
- return Visit(VD->getInit());
+ const VarDecl *Def = 0;
+ if (const Expr *Init = VD->getDefinition(Def))
+ return Visit(const_cast<Expr *>(Init));
}
return APValue();
@@ -793,11 +856,14 @@ bool IntExprEvaluator::VisitDeclRefExpr(const DeclRefExpr *E) {
// In C++, const, non-volatile integers initialized with ICEs are ICEs.
// In C, they can also be folded, although they are not ICEs.
- if (E->getType().getCVRQualifiers() == Qualifiers::Const) {
+ if (Info.Ctx.getCanonicalType(E->getType()).getCVRQualifiers()
+ == Qualifiers::Const) {
if (const VarDecl *D = dyn_cast<VarDecl>(E->getDecl())) {
- if (APValue *V = D->getEvaluatedValue())
- return Success(V->getInt(), E);
- if (const Expr *Init = D->getInit()) {
+ const VarDecl *Def = 0;
+ if (const Expr *Init = D->getDefinition(Def)) {
+ if (APValue *V = D->getEvaluatedValue())
+ return Success(V->getInt(), E);
+
if (Visit(const_cast<Expr*>(Init))) {
// Cache the evaluated value in the variable declaration.
D->setEvaluatedValue(Info.Ctx, Result);
@@ -873,6 +939,40 @@ bool IntExprEvaluator::VisitCallExpr(const CallExpr *E) {
switch (E->isBuiltinCall(Info.Ctx)) {
default:
return Error(E->getLocStart(), diag::note_invalid_subexpr_in_ice, E);
+
+ case Builtin::BI__builtin_object_size: {
+ const Expr *Arg = E->getArg(0)->IgnoreParens();
+ Expr::EvalResult Base;
+ if (Arg->EvaluateAsAny(Base, Info.Ctx)
+ && Base.Val.getKind() == APValue::LValue
+ && !Base.HasSideEffects)
+ if (const Expr *LVBase = Base.Val.getLValueBase())
+ if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(LVBase)) {
+ if (const VarDecl *VD = dyn_cast<VarDecl>(DRE->getDecl())) {
+ if (!VD->getType()->isIncompleteType()
+ && VD->getType()->isObjectType()
+ && !VD->getType()->isVariablyModifiedType()
+ && !VD->getType()->isDependentType()) {
+ uint64_t Size = Info.Ctx.getTypeSize(VD->getType()) / 8;
+ uint64_t Offset = Base.Val.getLValueOffset();
+ if (Offset <= Size)
+ Size -= Base.Val.getLValueOffset();
+ else
+ Size = 0;
+ return Success(Size, E);
+ }
+ }
+ }
+
+ if (HasSideEffects(E->getArg(0), Info.Ctx)) {
+ if (E->getArg(1)->EvaluateAsInt(Info.Ctx).getZExtValue() < 2)
+ return Success(-1ULL, E);
+ return Success(0, E);
+ }
+
+ return Error(E->getLocStart(), diag::note_invalid_subexpr_in_ice, E);
+ }
+
case Builtin::BI__builtin_classify_type:
return Success(EvaluateBuiltinClassifyType(E), E);
@@ -1801,6 +1901,33 @@ bool Expr::Evaluate(EvalResult &Result, ASTContext &Ctx) const {
return true;
}
+bool Expr::EvaluateAsAny(EvalResult &Result, ASTContext &Ctx) const {
+ EvalInfo Info(Ctx, Result, true);
+
+ if (getType()->isVectorType()) {
+ if (!EvaluateVector(this, Result.Val, Info))
+ return false;
+ } else if (getType()->isIntegerType()) {
+ if (!IntExprEvaluator(Info, Result.Val).Visit(const_cast<Expr*>(this)))
+ return false;
+ } else if (getType()->hasPointerRepresentation()) {
+ if (!EvaluatePointer(this, Result.Val, Info))
+ return false;
+ } else if (getType()->isRealFloatingType()) {
+ llvm::APFloat f(0.0);
+ if (!EvaluateFloat(this, f, Info))
+ return false;
+
+ Result.Val = APValue(f);
+ } else if (getType()->isAnyComplexType()) {
+ if (!EvaluateComplex(this, Result.Val, Info))
+ return false;
+ } else
+ return false;
+
+ return true;
+}
+
bool Expr::EvaluateAsLValue(EvalResult &Result, ASTContext &Ctx) const {
EvalInfo Info(Ctx, Result);
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