Subject: Re: tools build on ELF mac68k
To: None <firstname.lastname@example.org>
From: Matthew Fredette <fredette@MIT.EDU>
Date: 12/06/2001 13:13:35
> > I think what needs to happen is that strength_reduce needs to call
> > a version of reg_used_between_p that knows about "loop insn order".
> I think this has been fixed in gcc-3.0. Looking at an old'ish
> gcc-current tree I have, I see the following:
> Tue Sep 14 01:33:15 1999 Andreas Schwab <email@example.com>
> * loop.c (strength_reduce): Don't call reg_used_between_p if the
> insn from BL2 is after the insn from BL.
> The change was committed by Jeff Law in rev 1.186 of that file. The
> change is included below.
Sweet. Looks exactly on point. This change jives with my super-crude
understanding of how things work, and with it, the original ch.c
compiles. I compared the patched-cc1-original-ch.c assembly output to
the unpatched-cc1-stopgap-ch.c assembly output and the differences
make sense to me (strength reduction on `desc' within the for loop is
Now what? Should the patch just be committed to our gcc sources?