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Re: [PATCH, SH] PR target/56995


Christian Bruel <christian.bruel@st.com> wrote:
> So, Just removing DF_HI_REGS seems to fix the issue with strictly same
> performance results for SH4.
> 
>   No regressions in the testsuite for
>     sh-sim//-m2/
>     sh-sim//-m2a/
>     sh-sim//-m2a-nofpu/
>     sh-sim//-m2a-single/
>     sh-sim//-m2a-single-only/
>     sh-sim//-m3/
>     sh-sim//-m3e/
>     sh-sim//-m4/
>     sh-sim//-m4-single/
>     sh-sim//-m4-single-only/
>     sh-sim//-m4a/
>     sh-sim//-m4a-single/
>     sh-sim//-m4a-single-only/
> 
>  *[-mb,-ml]
> 
>  No performance regression for -m4

The patch is OK.
It seems that your patch does the right thing, though I don't
know the history of DF_HI_REGS at all.

> The consequence of this it that find_costs_and_classes seems to be
> confused when two register classes are strictly equivalent. Is it
> plausible ?

Looks very likely to me.

Regards,
	kaz


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