Remove Sema::CheckForIntOverflow, and instead check all full-expressions.
CheckForIntOverflow used to implement a whitelist of top-level expressions to
send to the constant expression evaluator, which handled many more expressions
than the CheckForIntOverflow whitelist did.
llvm-svn: 301742
diff --git a/clang/lib/AST/ExprConstant.cpp b/clang/lib/AST/ExprConstant.cpp
index dcbbe8a..75bb0ca 100644
--- a/clang/lib/AST/ExprConstant.cpp
+++ b/clang/lib/AST/ExprConstant.cpp
@@ -6217,6 +6217,10 @@
// the initializer list.
ImplicitValueInitExpr VIE(HaveInit ? Info.Ctx.IntTy : Field->getType());
const Expr *Init = HaveInit ? E->getInit(ElementNo++) : &VIE;
+ if (Init->isValueDependent()) {
+ Success = false;
+ continue;
+ }
// Temporarily override This, in case there's a CXXDefaultInitExpr in here.
ThisOverrideRAII ThisOverride(*Info.CurrentCall, &This,
@@ -9927,7 +9931,8 @@
}
static bool FastEvaluateAsRValue(const Expr *Exp, Expr::EvalResult &Result,
- const ASTContext &Ctx, bool &IsConst) {
+ const ASTContext &Ctx, bool &IsConst,
+ bool IsCheckingForOverflow) {
// Fast-path evaluations of integer literals, since we sometimes see files
// containing vast quantities of these.
if (const IntegerLiteral *L = dyn_cast<IntegerLiteral>(Exp)) {
@@ -9948,7 +9953,7 @@
// performance problems. Only do so in C++11 for now.
if (Exp->isRValue() && (Exp->getType()->isArrayType() ||
Exp->getType()->isRecordType()) &&
- !Ctx.getLangOpts().CPlusPlus11) {
+ !Ctx.getLangOpts().CPlusPlus11 && !IsCheckingForOverflow) {
IsConst = false;
return true;
}
@@ -9963,7 +9968,7 @@
/// will be applied to the result.
bool Expr::EvaluateAsRValue(EvalResult &Result, const ASTContext &Ctx) const {
bool IsConst;
- if (FastEvaluateAsRValue(this, Result, Ctx, IsConst))
+ if (FastEvaluateAsRValue(this, Result, Ctx, IsConst, false))
return IsConst;
EvalInfo Info(Ctx, Result, EvalInfo::EM_IgnoreSideEffects);
@@ -10088,7 +10093,7 @@
void Expr::EvaluateForOverflow(const ASTContext &Ctx) const {
bool IsConst;
EvalResult EvalResult;
- if (!FastEvaluateAsRValue(this, EvalResult, Ctx, IsConst)) {
+ if (!FastEvaluateAsRValue(this, EvalResult, Ctx, IsConst, true)) {
EvalInfo Info(Ctx, EvalResult, EvalInfo::EM_EvaluateForOverflow);
(void)::EvaluateAsRValue(Info, this, EvalResult.Val);
}
diff --git a/clang/lib/Sema/SemaChecking.cpp b/clang/lib/Sema/SemaChecking.cpp
index ea6f16e..b3ba86e 100644
--- a/clang/lib/Sema/SemaChecking.cpp
+++ b/clang/lib/Sema/SemaChecking.cpp
@@ -9866,28 +9866,6 @@
::CheckBoolLikeConversion(*this, E, CC);
}
-/// Diagnose when expression is an integer constant expression and its evaluation
-/// results in integer overflow
-void Sema::CheckForIntOverflow (Expr *E) {
- // Use a work list to deal with nested struct initializers.
- SmallVector<Expr *, 2> Exprs(1, E);
-
- do {
- Expr *E = Exprs.pop_back_val();
-
- if (isa<BinaryOperator>(E->IgnoreParenCasts())) {
- E->IgnoreParenCasts()->EvaluateForOverflow(Context);
- continue;
- }
-
- if (auto InitList = dyn_cast<InitListExpr>(E))
- Exprs.append(InitList->inits().begin(), InitList->inits().end());
-
- if (isa<ObjCBoxedExpr>(E))
- E->IgnoreParenCasts()->EvaluateForOverflow(Context);
- } while (!Exprs.empty());
-}
-
namespace {
/// \brief Visitor for expressions which looks for unsequenced operations on the
/// same object.
@@ -10389,7 +10367,7 @@
if (!E->isInstantiationDependent())
CheckUnsequencedOperations(E);
if (!IsConstexpr && !E->isValueDependent())
- CheckForIntOverflow(E);
+ E->EvaluateForOverflow(Context);
DiagnoseMisalignedMembers();
}