https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64905
H.J. Lu <hjl.tools at gmail dot com> changed:
What |Removed |Added
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CC| |vmakarov at redhat dot com
--- Comment #5 from H.J. Lu <hjl.tools at gmail dot com> ---
(In reply to Uroš Bizjak from comment #4)
> It looks the failure is due to:
>
> emit-rtl.c: REGNO_POINTER_ALIGN (HARD_FRAME_POINTER_REGNUM) =
> STACK_BOUNDARY;
>
> The testcase forces the pointer to %rbp (== HARD_FRAME_POINTER_REGNUM in the
> above line), so the predicate thinks that the value in %rbp is aligned,
> since %rbp has its REGNO_POINTER_ALIGN set to STACK_BOUNDARY.
>
> Looks like generic RTL infrastructure problem to me, the
> REGNO_POINTER_ALIGNMENT of hard_frame_pointer should be cleared when H_F_P
> is omitted and reused.
Like this
diff --git a/gcc/ira.c b/gcc/ira.c
index ea2b69f..a7cf476 100644
--- a/gcc/ira.c
+++ b/gcc/ira.c
@@ -2313,6 +2313,8 @@ ira_setup_eliminable_regset (void)
if (frame_pointer_needed)
df_set_regs_ever_live (HARD_FRAME_POINTER_REGNUM, true);
+ else
+ REGNO_POINTER_ALIGN (HARD_FRAME_POINTER_REGNUM) = 0;
COPY_HARD_REG_SET (ira_no_alloc_regs, no_unit_alloc_regs);
CLEAR_HARD_REG_SET (eliminable_regset);
