[Bug rtl-optimization/56571] New: ICE in copyprop_hardreg_forward_1, at regcprop.c (insn does not satisfy its constraints !)

[antoine.balestrat at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56571

             Bug #: 56571
           Summary: ICE in copyprop_hardreg_forward_1, at regcprop.c (insn
                    does not satisfy its constraints !)
    Classification: Unclassified
           Product: gcc
           Version: 4.8.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: rtl-optimization
        AssignedTo: unassig...@gcc.gnu.org
        ReportedBy: antoine.balest...@gmail.com


Hello !
The following testcase makes GCC 4.7.2 and 4.8.0 as of 20130308 fail.

$ cat insn.c
int a, b;

int f(void)
{
    (a % b) && f();
    a = (0 || a | (a ? : 1));
}

$ xgcc -w -O2 -funroll-loops -ftracer insn.c
insn.c: In function ‘f’:
insn.c:7:1: error: insn does not satisfy its constraints:
 }
 ^
(insn 83 79 84 9 (parallel [
            (set (reg:CCZ 17 flags)
                (compare:CCZ (ior:SI (reg:SI 4 si [81])
                        (reg:SI 2 cx [orig:69 D.1741 ] [69]))
                    (const_int 0 [0])))
            (clobber (reg:SI 39 r10 [81]))
        ]) insn.c:6 451 {*iorsi_3}
     (expr_list:REG_DEAD (reg:SI 2 cx [orig:69 D.1741 ] [69])
        (expr_list:REG_DEAD (reg:SI 0 ax [81])
            (expr_list:REG_UNUSED (reg:SI 0 ax [81])
                (nil)))))
insn.c:7:1: internal compiler error: in copyprop_hardreg_forward_1, at
regcprop.c:774
0x8a175a _fatal_insn(char const*, rtx_def const*, char const*, int, char
const*)
    ../../srcdir/gcc/rtl-error.c:109
0x8a177f _fatal_insn_not_found(rtx_def const*, char const*, int, char const*)
    ../../srcdir/gcc/rtl-error.c:120
0x87b1e7 copyprop_hardreg_forward_1
    ../../srcdir/gcc/regcprop.c:774
0x87b1e7 copyprop_hardreg_forward
    ../../srcdir/gcc/regcprop.c:1085
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