Re: [PATCH] hppa: Improve hppa_rtx_costs for shifts by constants.
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 > > 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
Re: [PATCH] hppa: Improve hppa_rtx_costs for shifts by constants.
Hi Roger, On 2020-08-27 12:42 p.m., Roger Sayle wrote: > 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 > > gcc/ChangeLog > * config/pa/pa.c (hppa_rtx_costs) [ASHIFT, ASHIFTRT, LSHIFTRT]: > Provide accurate costs for shifts of integer constants. Will test. -- John David Anglin dave.ang...@bell.net
Re: [PATCH] hppa: Improve hppa_rtx_costs for shifts by constants.
On Thu, 2020-08-27 at 17:42 +0100, 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 > > gcc/ChangeLog > * config/pa/pa.c (hppa_rtx_costs) [ASHIFT, ASHIFTRT, LSHIFTRT]: > Provide accurate costs for shifts of integer constants. Spinning in the tester. Figure results about this time tomorrow: http://3.14.90.209:8080/job/hppa-linux-gnu/944/console > jeff
