On Fri, Sep 22, 2017 at 6:03 AM, Jakub Jelinek wrote:
>
> 2017-09-22 Jakub Jelinek
>
> PR target/82274
> * internal-fn.c (expand_mul_overflow): If both operands have
> the same highpart of -1 or 0 and the topmost bit of lowpart
> is different, overflow is if res
Hi!
An overflow isn't detected on multiplication of signed integer
with all ones in the upper half of bits and all zeros in the lower half
by itself, either with -ftrapv, or __builtin_mul_overflow{,_p},
or signed-integer-overflow sanitization.
For libgcc, we have various cases we handle earlier (
