Il 19/03/2012 17:07, Ulrich Weigand ha scritto: > Hello, > > now that the apply_distributive_law change is in, I'd like to pick up > Richard's original patch, see discussion here: > http://gcc.gnu.org/ml/gcc-patches/2011-09/msg00852.html > > The version below integrates all requests for changes that were raised. > It's been part of Linaro GCC releases in this form for a while with no > problem reported. We see performance improvements in several libav loops, > as described in Richard's original mail. We've seen no test case so far > where this patch (against current baseline) has shown any significant > performance regressions. > > Re-tested on arm-linux-gnueabi and i386-linux-gnu with no regressions. > > OK for mainline? > > Bye, > Ulrich > > > ChangeLog: > > * fwprop.c (propagate_rtx): Also set PR_CAN_APPEAR for subregs. > > === modified file 'gcc/fwprop.c' > --- gcc/fwprop.c 2011-12-19 22:05:28 +0000 > +++ gcc/fwprop.c 2012-02-22 11:57:19 +0000 > @@ -664,7 +664,12 @@ > return NULL_RTX; > > flags = 0; > - if (REG_P (new_rtx) || CONSTANT_P (new_rtx)) > + if (REG_P (new_rtx) > + || CONSTANT_P (new_rtx) > + || (GET_CODE (new_rtx) == SUBREG > + && REG_P (SUBREG_REG (new_rtx)) > + && (GET_MODE_SIZE (mode) > + <= GET_MODE_SIZE (GET_MODE (SUBREG_REG (new_rtx)))))) > flags |= PR_CAN_APPEAR; > if (!for_each_rtx (&new_rtx, varying_mem_p, NULL)) > flags |= PR_HANDLE_MEM; >
I cannot approve it, but it looks good. Paolo
