On Sat, Jan 14, 2017 at 11:19 AM, Uros Bizjak <ubiz...@gmail.com> wrote: > On Fri, Jan 13, 2017 at 4:58 PM, Uros Bizjak <ubiz...@gmail.com> wrote: >> On Fri, Jan 13, 2017 at 12:50 PM, Alan Modra <amo...@gmail.com> wrote: >>> Rather than using unspecs in doloop insns to stop combine creating >>> these insns, use legitimate_combined_insn. >>> >>> I'm not sure why the original patch implementing >>> legitimate_combined_insn did not store the result of recog to the insn >>> but it seems good to me, and would allow the recog call in >>> ix86_legitimate_combined_insn to be omitted. (I tested that too, not >>> shown here.) >> >> IIRC, I copied operand scanning loop from recog.c (around line 2580) >> and the function was later enhanced with preferred alternatives >> handling. The function worked well, and not being an expert in this >> area, I didn't try to "optimize" the code that worked... >> >> So, there is no particular reason for the current implementation. > > FYI, the following patch immediately crashed build:
Bah, it would help if I actually saved source with proposed combine.c change. Testing the patch... Uros.
