On Mon, Aug 3, 2020 at 2:20 AM Richard Biener via Gcc-patches
wrote:
>
> On Sun, Aug 2, 2020 at 6:31 PM Roger Sayle wrote:
> >
> >
> >
> > PR rtl-optimization/60473 was a code quality regression that has
> >
> > been cured by improvements to register allocation. For the function
> >
> > in the t
>> Since GCC 4.9 (including current mainline), it generates optimal
>>
>> code with no mov instructions, matching what used to be generated
>>
>> in GCC 4.1.
>>
>>
>>
>> foo:rdtsc
>>
>> sal rdx, 32
>>
>> or rax, rdx
>>
>> ret
>>
>>
>>
>> This test case, which ha
On Sun, Aug 2, 2020 at 6:31 PM Roger Sayle wrote:
>
>
>
> PR rtl-optimization/60473 was a code quality regression that has
>
> been cured by improvements to register allocation. For the function
>
> in the test case, GCC 4.4, 4.5 and 4.6 generated very poor code
>
> requiring two mov instructions
PR rtl-optimization/60473 was a code quality regression that has
been cured by improvements to register allocation. For the function
in the test case, GCC 4.4, 4.5 and 4.6 generated very poor code
requiring two mov instructions:
foo:rdtsc
mov rcx, rax
mov ra
