------- Comment #51 from bergner at gcc dot gnu dot org 2008-04-08 18:50
-------
Ok, I dug into this a little deeper. For the following test case:
int array[1024];
void
clear_table (unsigned int n)
{
unsigned int i;
for (i = 0; i < n; i++)
array[i] = 0;
}
compiling this with -O1 (it's ok with -O2 or above) on powerpc{,64}-linux,
during expand, we call swap_commutative_operands_p with a SYMBOL_REF and a REG
which currently prefers the REG first. Later, break_out_memory_refs forces the
SYMBOL_REF into a register (with the REG_POINTER attribute set), but we're
already done swapping, so we get the wrong operand ordering. Paolo, I wonder
if this patch instead of the rtlanal.c hunk might be better. It does fix my
problem:
Index: explow.c
===================================================================
--- explow.c (revision 134095)
+++ explow.c (working copy)
@@ -305,7 +305,7 @@ break_out_memory_refs (rtx x)
rtx op1 = break_out_memory_refs (XEXP (x, 1));
if (op0 != XEXP (x, 0) || op1 != XEXP (x, 1))
- x = gen_rtx_fmt_ee (GET_CODE (x), Pmode, op0, op1);
+ x = simplify_gen_binary (GET_CODE (x), Pmode, op0, op1);
}
return x;
--
bergner at gcc dot gnu dot org changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|RESOLVED |REOPENED
Resolution|FIXED |
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28690
