On Fri, Aug 13, 2021 at 4:24 PM Segher Boessenkool <seg...@kernel.crashing.org> wrote: > > On Fri, Aug 13, 2021 at 02:07:25PM -0400, David Edelsohn wrote: > > On Fri, Aug 13, 2021 at 12:08 PM Segher Boessenkool > > <seg...@kernel.crashing.org> wrote: > > > > > > On Fri, Aug 13, 2021 at 11:15:21AM -0400, David Edelsohn wrote: > > > > On Fri, Aug 13, 2021 at 10:49 AM Segher Boessenkool > > > > <seg...@kernel.crashing.org> wrote: > > > > > > > > > > On Fri, Aug 13, 2021 at 12:14:14AM -0400, Michael Meissner wrote: > > > > > > I noticed that the xxeval built-in function used the > > > > > > altivec_register_operand > > > > > > predicate. Since it takes vsx registers, this might force the > > > > > > register > > > > > > allocate to issue a move when it could use a traditional floating > > > > > > point > > > > > > register. This patch fixes that. > > > > > > > > > > Why register_operand instead of gpc_reg_operand? The former allows > > > > > subregs of memory, likely not what you want here (and not in other > > > > > rs6000 pattern that currently use it, either). > > > > > > > > Because it's consistent with the other patterns. > > > > > > Not with the vast majority of other patterns, no. > > > > For vector operands in altivec.md, if the predicates do not use > > altivec_register_operand, they use register_operand, not > > gpc_reg_operand. Mike's change is consistent with the rest of the > > altivec.md file. > > > > Maybe the predicates for those patterns should be changed. Maybe that > > change would be an improvement. > > > > Your statement about the vast majority of patterns is wrong with > > respect to altivec.md. > > There is nothing about that file that makes it any different for this? > > Anyway, the numbers: > > gpc_reg_operand register_operand > config/rs6000/altivec.md 11 760 > config/rs6000/crypto.md 0 14 > config/rs6000/darwin.md 25 1 > config/rs6000/dfp.md 71 3 > config/rs6000/fusion.md 349 0 > config/rs6000/htm.md 10 0 > config/rs6000/mma.md 4 0 > config/rs6000/pcrel-opt.md 8 0 > config/rs6000/rs6000.md 1105 116 > config/rs6000/sync.md 0 3 > config/rs6000/vector.md 0 29 > config/rs6000/vsx.md 102 122
There is a song from Sesame Street: "Which of these is not like the others?" altivec.md seems like an outlier. crypto.md and vsx.md also seem unusual. We have register_operand gpc_reg_operand altivec_register_operand vsx_register_operand among various relevant options. It seems like this deserves to be cleaned up sometime, but a patch for xxeval is not the time. Thanks, David
