On Fri, Oct 26, 2012 at 8:30 AM, H.J. Lu <hjl.to...@gmail.com> wrote: > On Thu, Oct 25, 2012 at 11:21 PM, Jakub Jelinek <ja...@redhat.com> wrote: >> On Thu, Oct 25, 2012 at 11:15:06PM -0700, H.J. Lu wrote: >>> Should there be a -fno-ira option before reload pass is >>> removed? It will be useful to investiage IRA regressions. >> >> You mean -fno-lra, and s/IRA/LRA/, right? I think the reason for no > > Yes, I meant -fno-lra. > >> compiler switch is that while returning false from ix86_lra_p () >> likely works right now, -fno-lra mode would be yet another >> thing to support. So, for investigations just return false from ix86_lra_p, >> similarly for benchmarking, but as it needs compiler source changes, it is >> obvious that with old reload everybody is on their own if it breaks >> for targets that switched to LRA. >> > > I'd like to compare glibc code quality on x32, x86-64 and ia32 > with and without LRA. We don't even need to document -fno-lra > or we can make it -mno-lra as x86 undocumented switch. I > expect -fno-lra/-mno-lra will only be useful in a short period > of time.
You can always compare to the revision before LRA merged. My understanding is that -fno-lra is not easily possible as backends change in non-trivial ways once they go the LRA way. Thus you'd not compare what you want to compare. Richard. > > -- > H.J.