On Tue, Oct 7, 2014 at 1:20 AM, Mike Stump <mikest...@comcast.net> wrote: > On Oct 6, 2014, at 4:32 AM, Richard Biener <richard.guent...@gmail.com> wrote: >> On Mon, Oct 6, 2014 at 11:57 AM, Bin.Cheng <amker.ch...@gmail.com> wrote: >> >> How many merging opportunities does sched2 undo again? ISTR it >> has the tendency of pushing stores down and loads up. > > So, the pass works by merging 2 or more loads into 1 load (at least on my > port). sched2 would need to rip apart 1 load into 2 loads to be able to undo > the real work. The non-real work, doesn't matter any. Can sched2 rip apart > a single load? On ARM and AARCH64, the two merged load/store are transformed into single parallel insn by the following peephole2 pass, so that sched2 would not undo the fusion work. I though sched2 works on the basis of instructions, and it isn't good practice to have sched2 do split work.
Thanks, bin
