[Bug rtl-optimization/66412] [5/6 Regression] ICE on valid code at -O2 and -O3 with -g enabled in simplify_subreg, at simplify-rtx.c:5748

[ubizjak at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66412

--- Comment #2 from Uroš Bizjak <ubizjak at gmail dot com> ---
(gdb) bt
#0  internal_error (gmsgid=0x1d02fb5 "in %s, at %s:%d") at
/home/uros/gcc-svn/trunk/gcc/diagnostic.c:1270
#1  0x00000000017291d7 in fancy_abort (file=0x1863c90
"/home/uros/gcc-svn/trunk/gcc/simplify-rtx.c", line=5750, 
    function=0x1864b40 <simplify_subreg(machine_mode, rtx_def*, machine_mode,
unsigned int)::__FUNCTION__> "simplify_subreg")
    at /home/uros/gcc-svn/trunk/gcc/diagnostic.c:1340
#2  0x0000000000d71e51 in simplify_subreg (outermode=HImode, op=0x2aaaae8eacd8,
innermode=SImode, byte=0)
    at /home/uros/gcc-svn/trunk/gcc/simplify-rtx.c:5749
#3  0x0000000000d72b41 in simplify_gen_subreg (outermode=HImode,
op=0x2aaaae8eacd8, innermode=SImode, byte=0)
    at /home/uros/gcc-svn/trunk/gcc/simplify-rtx.c:5969
#4  0x0000000000d77a93 in simplify_replace_fn_rtx (x=0x2aaaae8ea5b8,
old_rtx=0x2aaaae8ea2d0, 
    fn=0x10c06e6 <propagate_for_debug_subst(rtx, const_rtx, void*)>,
data=0x7fffffffc490) at /home/uros/gcc-svn/trunk/gcc/simplify-rtx.c:511
#5  0x00000000010c0685 in propagate_for_debug (insn=0x2aaaae7bc480,
last=0x2aaaae7bc5c0, dest=0x2aaaae8ea2d0, src=0x2aaaae8eaa38, 
    this_basic_block=0x2aaaae7b3958) at
/home/uros/gcc-svn/trunk/gcc/valtrack.c:205
#6  0x00000000015e1a04 in try_combine (i3=0x2aaaae7bc580, i2=0x2aaaae7bc540,
i1=0x2aaaae7bc400, i0=0x0, new_direct_jump_p=0x7fffffffcc04, 
    last_combined_insn=0x2aaaae7bc580) at
/home/uros/gcc-svn/trunk/gcc/combine.c:4386

(gdb) f 2
#2  0x0000000000d71e51 in simplify_subreg (outermode=HImode, op=0x2aaaae8eacd8,
innermode=SImode, byte=0)
    at /home/uros/gcc-svn/trunk/gcc/simplify-rtx.c:5749
5749      gcc_assert (GET_MODE (op) == innermode
(gdb) p op
$18 = (rtx) 0x2aaaae8eacd8
(gdb) p debug_rtx (op)
(eq:QI (reg:CCZ 17 flags)
    (const_int 0 [0]))