| Message ID | 87ip30umyt.fsf@redhat.com |
|---|---|
| State | New |
| Headers | show |
On 05/03/2013 09:01 AM, Nick Clifton wrote: > Hi Guys, > > I would like to apply the patch below to allow simplify_subreg_regno() > to treat the frame pointer register in the same way as the stack > pointer register when the LRA pass is running. I found that I needed > this whilst trying to enable LRA for the RX and RL78 targets. (LRA is > still not working for these targets, but this patch lets more of > libgcc be built than before). > > No regressions noted on an i686-pc-linux-gnu toolchain built with this > patch applied. OK to apply ? > > Cheers > Nick > > gcc/ChangeLog > 2013-05-03 Nick Clifton <nickc@redhat.com> > > * rtlanal.c (simplify_subreg_regno): Allow simplification of > SUBREGs involving the frame pointer when running the LRA pass. Ewwwww. Before accepting this, I'd like to see more of the rationale behind the change. jeff
Hi Jeff, >> I would like to apply the patch below to allow simplify_subreg_regno() >> to treat the frame pointer register in the same way as the stack >> pointer register when the LRA pass is running. > Ewwwww. > > Before accepting this, I'd like to see more of the rationale behind the > change. *sigh* Of course now I cannot reproduce the failure that this patch used to fix. Oh well. I withdraw the patch for now and if I can find a way to reproduce the problem I will post the patch again along with a more complete description of what is happening. Cheers Nick
Index: gcc/rtlanal.c =================================================================== --- gcc/rtlanal.c (revision 198496) +++ gcc/rtlanal.c (working copy) @@ -3481,8 +3481,10 @@ return -1; #endif - /* We shouldn't simplify stack-related registers. */ + /* We shouldn't simplify stack-related registers... */ if ((!reload_completed || frame_pointer_needed) + /* ...unless we are in LRA that is. */ + && ! lra_in_progress && xregno == FRAME_POINTER_REGNUM) return -1;