On Mon, Nov 09, 2015 at 08:52:13AM +0100, Uros Bizjak wrote: > On Sun, Nov 8, 2015 at 9:58 PM, Segher Boessenkool > <seg...@kernel.crashing.org> wrote: > > On Fri, Nov 06, 2015 at 04:00:08PM -0600, Segher Boessenkool wrote: > >> This patch stops combine from generating widening muls of anything else > >> but registers (immediates, memory, ...). This probably is a reasonable > >> tradeoff for all targets, even those (if any) that have such insns. > >> > >> > >I'll let you put it through it's paces on your setup :) > >> > >> > I'll let Segher give the final yes/no on this, but it generally looks > >> > good to me. > >> > >> It looks okay to me too. Testing now, combine patches have the tendency > >> to do unforeseen things on other targets ;-) > > > > Testing shows it makes a difference only very rarely. For many targets > > it makes no difference, for a few it is a small win. For 32-bit x86 it > > creates slightly bigger code. > > > > I think it looks good, but let's wait to hear Uros' opinion. > > >From the original patch submission, it looks that this patch would > also benefit x86_32.
Yes, that is what I thought too. > Regarding the above code size increase - do you perhaps have a > testcase, to see what causes the difference? I could extract some. It happens quite rarely on usual code. > It isn't necessary due to > the patch, but perhaps some loads are moved to the insn and aren't > CSE'd anymore. Segher