================
@@ -3542,6 +3542,56 @@ bool CallExpr::isBuiltinAssumeFalse(const ASTContext
&Ctx) const {
Arg->EvaluateAsBooleanCondition(ArgVal, Ctx) && !ArgVal;
}
+const AllocSizeAttr *CallExpr::getCalleeAllocSizeAttr() const {
+ if (const FunctionDecl *DirectCallee = getDirectCallee())
+ return DirectCallee->getAttr<AllocSizeAttr>();
+ if (const Decl *IndirectCallee = getCalleeDecl())
+ return IndirectCallee->getAttr<AllocSizeAttr>();
+ return nullptr;
+}
+
+std::optional<llvm::APInt>
+CallExpr::getBytesReturnedByAllocSizeCall(const ASTContext &Ctx) const {
+ const AllocSizeAttr *AllocSize = getCalleeAllocSizeAttr();
+
+ assert(AllocSize && AllocSize->getElemSizeParam().isValid());
+ unsigned SizeArgNo = AllocSize->getElemSizeParam().getASTIndex();
+ unsigned BitsInSizeT = Ctx.getTypeSize(Ctx.getSizeType());
+ if (getNumArgs() <= SizeArgNo)
+ return {};
+
+ auto EvaluateAsSizeT = [&](const Expr *E, llvm::APSInt &Into) {
+ Expr::EvalResult ExprResult;
+ if (E->isValueDependent() ||
+ !E->EvaluateAsInt(ExprResult, Ctx, Expr::SE_AllowSideEffects))
+ return false;
+ Into = ExprResult.Val.getInt();
+ if (Into.isNegative() || !Into.isIntN(BitsInSizeT))
----------------
erichkeane wrote:
Does this need to be BitsInSizeT-1? In the case where the `size_t` is signed,
but the expression is unsigned-same-bits-as-size_t?
That would make the `EvaluateAsSizeT` result in a negative value.
https://github.com/llvm/llvm-project/pull/150028
_______________________________________________
cfe-commits mailing list
[email protected]
https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
