On Tue, 2007-03-06 at 18:18 +0100, Paolo Bonzini wrote:
> > It would be really sweet if we propagated the 'di - 4' into insn 8, then
> > recognized that di is now the value of SI 58, and propagated di into the
> > compare. insn 7 would be dead and we'd get the code the PR is looking
> > for :-)
>
> It would be really sweet if we propagated the 'di - 4' into insn 8, then
> recognized that di is now the value of SI 58, and propagated di into the
> compare. insn 7 would be dead and we'd get the code the PR is looking
> for :-)
Unfortunately there's no hope of that because fwprop doesn't do
I was working on a a patch for PR 21596, and it seems to have triggered
a bug in fwprop on x86 in mainline.
The testcase is simple:
register int *reg __asm__("%edi");
int test () { return *--reg <= 0; }
I've attached the patch for TER which changes the tree produced in
mainline from:
re
