http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49452
--- Comment #23 from Carrot <carrot at google dot com> 2011-09-16 06:57:15 UTC
---
(In reply to comment #21)
> > All callee saved registers should never changed after function call. Here fp
> > has been changed is not because it is after a function call, it is because
> > it
> > is after the target of non local goto. I'm not familiar with the
> > implementation
> > of non local goto, but I guess there is some convention/protocol defines
> > which
> > registers may be changed after the target of a non local goto.
>
> That's not the problem. The problem is that the blockage isn't honored.
It seems postreload.c should be changed to the following to avoid combining
--- postreload.c (revision 178904)
+++ postreload.c (working copy)
@@ -1312,7 +1312,7 @@ reload_combine (void)
is and then later disable any optimization that would cross it. */
if (LABEL_P (insn))
last_label_ruid = reload_combine_ruid;
- else if (BARRIER_P (insn))
+ else if (BARRIER_P (insn) || BLOCKAGE_P (insn))
for (r = 0; r < FIRST_PSEUDO_REGISTER; r++)
if (! fixed_regs[r])
reg_state[r].use_index = RELOAD_COMBINE_MAX_USES;
BLOCKAGE_P (insn) is used to detect if insn is a blockage insn, is there any
available function/macro that implement this functionality?
