[Bug target/115749] Non optimal assembly for integer modulo by a constant on x86-64 CPUs

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115749

Andrew Pinski <pinskia at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         Depends on|                            |115755

--- Comment #6 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
(In reply to Andrew Pinski from comment #5)
> The mulx issue can be reduced down to just:
> ```
> unsigned long func(unsigned long x)
> {
>   __uint128_t t = x;
>   return (t * 123)>>64;
> }
> 
> 
> __uint128_t func1(unsigned long x, unsigned long y)
> {
>   __uint128_t t = x;
>   return (t * 123);
> }
> 
> ```
> 
> It only happens with constants it seems.

I split that out to PR 115755.


Referenced Bugs:

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=115755
[Bug 115755] mulx (with -mbmi2) does not show up with constant multiply