------- Comment #3 from rguenth at gcc dot gnu dot org 2010-02-04 10:33 -------
Well, dse puts
(mem/u/f/c/i:DI (symbol_ref:DI ("q") [flags 0x2] <var_decl 0x7ffff5ae7140 q>)
[0 q+0 S8 A64])
(mem/u/f/c/i:DI (symbol_ref:DI ("p") [flags 0x2] <var_decl 0x7ffff5ae70a0 p>)
[0 p+0 S8 A64])
into different groups:
**scanning insn=9
cselib value 2 0x10f8e58 (reg/f:DI 63 [ q ])
cselib lookup (reg/f:DI 63 [ q ]) => 2
mem: (reg/f:DI 63 [ q ])
after canon_rtx address: (mem/u/f/c/i:DI (symbol_ref:DI ("q") [flags 0x2]
<var_decl 0x7ffff5ae7140 q>) [0 q+0 S8 A64])
gid=2 offset=0
processing const load gid=2[0..4)
mems_found = 0, cannot_delete = true
cselib lookup (mem:SI (reg/f:DI 63 [ q ]) [0 S4 A32]) => 0
**scanning insn=10
cselib lookup (reg/f:DI 58 [ p.0 ]) => 1
mem: (reg/f:DI 58 [ p.0 ])
after canon_rtx address: (mem/u/f/c/i:DI (symbol_ref:DI ("p") [flags 0x2]
<var_decl 0x7ffff5ae70a0 p>) [0 p+0 S8 A64])
gid=1 offset=0
processing const base store gid=1[0..4)
trying store in insn=7 gid=1[0..4)
just because the addresses are MEM_READONLY_P. But that obviously does not
mean they do not point to the same thing - no idea what implementor had
in mind here. Kenny?
The following fixes this for me:
Index: dse.c
===================================================================
--- dse.c (revision 156468)
+++ dse.c (working copy)
@@ -1015,9 +1015,6 @@ const_or_frame_p (rtx x)
{
switch (GET_CODE (x))
{
- case MEM:
- return MEM_READONLY_P (x);
-
case CONST:
case CONST_INT:
case CONST_DOUBLE:
--
rguenth at gcc dot gnu dot org changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |zadeck at gcc dot gnu dot
| |org
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42952
