[cfe-commits] r81672 - in /cfe/trunk: include/clang/AST/Expr.h lib/AST/ExprConstant.cpp
Eli Friedman
eli.friedman at gmail.com
Sun Sep 13 03:17:45 PDT 2009
Author: efriedma
Date: Sun Sep 13 05:17:44 2009
New Revision: 81672
URL: http://llvm.org/viewvc/llvm-project?rev=81672&view=rev
Log:
Add utility to evaluate lvalues which are an offset relative to a stack
location. Patch by Enea Zaffanella.
Modified:
cfe/trunk/include/clang/AST/Expr.h
cfe/trunk/lib/AST/ExprConstant.cpp
Modified: cfe/trunk/include/clang/AST/Expr.h
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/AST/Expr.h?rev=81672&r1=81671&r2=81672&view=diff
==============================================================================
--- cfe/trunk/include/clang/AST/Expr.h (original)
+++ cfe/trunk/include/clang/AST/Expr.h Sun Sep 13 05:17:44 2009
@@ -248,9 +248,14 @@
/// must be called on an expression that constant folds to an integer.
llvm::APSInt EvaluateAsInt(ASTContext &Ctx) const;
- /// EvaluateAsLValue - Evaluate an expression to see if it's a valid LValue.
+ /// EvaluateAsLValue - Evaluate an expression to see if it's a lvalue
+ /// with link time known address.
bool EvaluateAsLValue(EvalResult &Result, ASTContext &Ctx) const;
+ /// EvaluateAsAnyLValue - The same as EvaluateAsLValue, except that it
+ /// also succeeds on stack based, immutable address lvalues.
+ bool EvaluateAsAnyLValue(EvalResult &Result, ASTContext &Ctx) const;
+
/// isNullPointerConstant - C99 6.3.2.3p3 - Return true if this is either an
/// integer constant expression with the value zero, or if this is one that is
/// cast to void*.
Modified: cfe/trunk/lib/AST/ExprConstant.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/AST/ExprConstant.cpp?rev=81672&r1=81671&r2=81672&view=diff
==============================================================================
--- cfe/trunk/lib/AST/ExprConstant.cpp (original)
+++ cfe/trunk/lib/AST/ExprConstant.cpp Sun Sep 13 05:17:44 2009
@@ -46,8 +46,12 @@
/// EvalResult - Contains information about the evaluation.
Expr::EvalResult &EvalResult;
- EvalInfo(ASTContext &ctx, Expr::EvalResult& evalresult) : Ctx(ctx),
- EvalResult(evalresult) {}
+ /// AnyLValue - Stack based LValue results are not discarded.
+ bool AnyLValue;
+
+ EvalInfo(ASTContext &ctx, Expr::EvalResult& evalresult,
+ bool anylvalue = false)
+ : Ctx(ctx), EvalResult(evalresult), AnyLValue(anylvalue) {}
};
@@ -189,7 +193,7 @@
if (isa<FunctionDecl>(E->getDecl())) {
return APValue(E, 0);
} else if (VarDecl* VD = dyn_cast<VarDecl>(E->getDecl())) {
- if (!VD->hasGlobalStorage())
+ if (!Info.AnyLValue && !VD->hasGlobalStorage())
return APValue();
if (!VD->getType()->isReferenceType())
return APValue(E, 0);
@@ -209,9 +213,9 @@
}
APValue LValueExprEvaluator::VisitCompoundLiteralExpr(CompoundLiteralExpr *E) {
- if (E->isFileScope())
- return APValue(E, 0);
- return APValue();
+ if (!Info.AnyLValue && !E->isFileScope())
+ return APValue();
+ return APValue(E, 0);
}
APValue LValueExprEvaluator::VisitMemberExpr(MemberExpr *E) {
@@ -1786,6 +1790,12 @@
return EvaluateLValue(this, Result.Val, Info) && !Result.HasSideEffects;
}
+bool Expr::EvaluateAsAnyLValue(EvalResult &Result, ASTContext &Ctx) const {
+ EvalInfo Info(Ctx, Result, true);
+
+ return EvaluateLValue(this, Result.Val, Info) && !Result.HasSideEffects;
+}
+
/// isEvaluatable - Call Evaluate to see if this expression can be constant
/// folded, but discard the result.
bool Expr::isEvaluatable(ASTContext &Ctx) const {
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