Hi Roger,

This change is fine.  PR middle-end/87256 remains resolved.

I'll have to tweak the shadd-2 test again.  The number of sh*add instructions 
dropped
to three but the total number of instruction dropped by one.

Thanks,
Dave

On 2020-08-27 12:42 p.m., Roger Sayle wrote:
> Hi Dave (and Jeff),
> For your consideration, here's a patch that should fix the recent regression
> of gcc.dg/tree-ssa/slrt-13.c on hppa targets.
>
> This patch provides more accurate rtx_costs estimates for shifts by
> integer constants (which are cheaper than by a register amount).
> Fine tuning these is sufficient to have simple-ssa-strength-reduce
> prefer multiplications by four, over multiplications by five.
>
> Technically only the ASHIFT is required to fix the regression, but for
> symmetry
> I've added the appropriate PA-RISC values for all three shift types (in
> SImode).
> I've also checked that this doesn't reintroduce PR middle-end/87256.
>
> I was wondering whether you could please "put this in the queue", and
> reconfirm that PR middle-end/87256 remains resolved?
>
>
> 2020-08-27  Roger Sayle  <ro...@nextmovesoftware.com>
>
> gcc/ChangeLog
>       * config/pa/pa.c (hppa_rtx_costs) [ASHIFT, ASHIFTRT, LSHIFTRT]:
>       Provide accurate costs for shifts of integer constants.
>
> Many thanks in advance (and my apologies for the inconvenience),
> Roger
> --
> Roger Sayle
> NextMove Software
> Cambridge, UK
>


-- 
John David Anglin  dave.ang...@bell.net

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