https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66140
Uroš Bizjak <ubizjak at gmail dot com> changed:
What |Removed |Added
----------------------------------------------------------------------------
Status|UNCONFIRMED |NEW
Last reconfirmed| |2015-05-14
CC| |rth at gcc dot gnu.org,
| |ubizjak at gmail dot com
Ever confirmed|0 |1
--- Comment #1 from Uroš Bizjak <ubizjak at gmail dot com> ---
Confirmed with a cross from x86_64-linux-gnu.
The problem is with (insn 56), where reload does:
Reloads for insn # 56
Reload 0: reload_in (DI) = (reg/v/f:DI 71 [ bpl ])
GENERAL_REGS, RELOAD_FOR_OUTPUT_ADDRESS (opnum = 0)
reload_in_reg: (reg/v/f:DI 71 [ bpl ])
reload_reg_rtx: (reg:DI 4 $4)
Reload 1: GENERAL_REGS, RELOAD_FOR_OUTPUT_ADDRESS (opnum = 0), can't combine,
secondary_reload_p
reload_reg_rtx: (reg:TI 2 $2)
Reload 2: reload_out (QI) = (mem:QI (plus:DI (reg/v/f:DI 71 [ bpl ])
(const_int 3 [0x3])) [1
*bpl_5+3 S1 A8])
GENERAL_REGS, RELOAD_FOR_OUTPUT (opnum = 0)
reload_out_reg: (mem:QI (plus:DI (reg/v/f:DI 71 [ bpl ])
(const_int 3 [0x3])) [1
*bpl_5+3 S1 A8])
reload_reg_rtx: (reg:QI 5 $5)
secondary_out_reload = 1
secondary_out_icode = reload_outqi
Tracing the RTX through reload_outqi, we enter with operands[0]:
(mem:QI (plus:DI (reg/v/f:DI 71 [ bpl ])
(const_int 3 [0x3])) [1 *bpl_5+3 S1 A8])
and get_unaligned_addr returns:
(plus:DI (reg/v/f:DI 71 [ bpl ])
(const_int 3 [0x3]))
But ... (reg/v/f:DI 71 [ bpl ]) is scheduled for reload in Reload 0, and got
its replacement register (reg:DI 4 $4).
So, we have to call find_replacement in get_unaligned_address, even if (ref) is
otherwise correct memory_address_p operand.
With the (totaly untested) patch below, get_unaligned_address returns:
(plus:DI (reg:DI 4 $4)
(const_int 3 [0x3]))
--cut here--
Index: alpha.c
===================================================================
--- alpha.c (revision 223201)
+++ alpha.c (working copy)
@@ -1602,8 +1602,7 @@ get_unaligned_address (rtx ref)
gcc_assert (MEM_P (ref));
- if (reload_in_progress
- && ! memory_address_p (GET_MODE (ref), XEXP (ref, 0)))
+ if (reload_in_progress)
{
base = find_replacement (&XEXP (ref, 0));
--cut here--
