On Wed, Dec 23, 2009 at 10:06 AM, Paolo Bonzini <bonz...@gnu.org> wrote: > On 12/23/2009 06:47 PM, H.J. Lu wrote: >> >> On Wed, Dec 23, 2009 at 8:41 AM, Paolo Bonzini<bonz...@gnu.org> wrote: >>> >>> On 12/23/2009 04:19 PM, Bingfeng Mei wrote: >>>> >>>> It seems that just commenting out this check in fwprop.c should work. >>> >>> Yes, but it would pessimize x86. >>> >> >> Is there a bug open for x86? Can't we make it target dependent, something >> like >> >> /* Do not propagate loop invariant definitions inside the loop. */ >> if (targetm.foobar >> && DF_REF_BB (def)->loop_father != DF_REF_BB (use)->loop_father) >> return; > > I'll open a bug. The solution is to actually understand what the address > costs are on x86 (apparently it's not true that the more complex addressing > modes are always better, probably because of instruction sizes), not to add > a target macro. >
I will ask around to see if there are any guild lines for this after the bug is open. Thanks. -- H.J.
