Re: [PATCH, i386]: Extend TARGET_READ_MODIFY{,_WRITE} peepholes to all integer modes

[Eric Botcazou <ebotcazou@adacore.com>]

> Attached patch was actually tested on a couple of cases. It generates
> the same assembly as before.

Note that you could just remove the second ":W" in the define_insn pattern.

That's better, but not quite it because this segfaults at -O2:

#0  memory_operand (op=0xabababababababab, mode=mode@entry=VOIDmode)
    at /home/eric/svn/gcc/gcc/recog.c:1360
#1  0x00000000014388b1 in get_attr_memory (insn=insn@entry=0x7ffff697b8c0)
    at /home/eric/svn/gcc/gcc/config/i386/i386.md:2120
#2  0x0000000001636fb8 in insn_default_latency_generic (insn=0x7ffff697b8c0)
    at /home/eric/svn/gcc/gcc/config/i386/i386.md:27394
#3  0x00000000017f9695 in insn_cost (insn=0x7ffff697b8c0)
    at /home/eric/svn/gcc/gcc/haifa-sched.c:1415
#4  0x00000000017feb75 in dep_cost_1 (link=link@entry=0x2e962e8, 
dw=dw@entry=0)
    at /home/eric/svn/gcc/gcc/haifa-sched.c:1468
#5  0x0000000001800d7a in dep_cost (link=0x2e962e8)
    at /home/eric/svn/gcc/gcc/haifa-sched.c:1523
#6  priority (insn=0x7ffff697b8c0) at /home/eric/svn/gcc/gcc/haifa-
sched.c:1674
#7  0x0000000001800e6f in set_priorities (head=<optimized out>, 
    tail=<optimized out>) at /home/eric/svn/gcc/gcc/haifa-sched.c:7209
#8  0x0000000000f689e3 in compute_priorities ()
    at /home/eric/svn/gcc/gcc/sched-rgn.c:3022
#9  0x0000000000f6bc46 in schedule_region (rgn=0)
    at /home/eric/svn/gcc/gcc/sched-rgn.c:3115
#10 schedule_insns () at /home/eric/svn/gcc/gcc/sched-rgn.c:3513
#11 0x0000000000f6c4de in schedule_insns ()

(gdb) frame 1
#1  0x00000000014388b1 in get_attr_memory (insn=insn@entry=0x7ffff697b8c0)
    at /home/eric/svn/gcc/gcc/config/i386/i386.md:2120
2120                   (match_test "TARGET_AVX")
(gdb) p debug_rtx(insn)
(insn 779 927 928 2 (parallel [
            (set (mem/v:DI (reg/f:DI 7 sp) [0  S8 A8])
                (unspec:DI [
                        (const_int 0 [0])
                    ] UNSPEC_PROBE_STACK))
            (clobber (reg:CC 17 flags))
        ]) c52104y.adb:57 1005 {probe_stack_di}
     (expr_list:REG_UNUSED (reg:CC 17 flags)
        (nil)))
$1 = void

-- 
Eric Botcazou