reload ICE during ada and go bootstrap on x86_64

[Martin Sebor]

I've been running into the following errors during the bootstrap
of the top of trunk on x86_64 with no local changes.   They don't
seem to be triggered by other front ends.  Before I open a new
bug, has anyone else noticed them and maybe already filed one?
(I don't see anything recent in Bugzilla but I could be looking
for the wrong thing.)

Thanks
Martin

/opt/notnfs/msebor/src/gcc/82301/libgo/go/cmd/go/internal/load/pkg.go:377:1: 
error: this is the insn:
(insn 1134 2835 2611 195 (parallel [
             (set (reg:DI 492)
                 (const_int 0 [0]))
             (set (reg/f:DI 1008 [orig:490 <retval> ] [490])
                 (plus:DI (ashift:DI (reg:DI 492)
                         (const_int 3 [0x3]))
                     (reg/f:DI 1008 [orig:490 <retval> ] [490])))
             (set (reg/f:DI 1009 [880])
                 (plus:DI (ashift:DI (reg:DI 492)
                         (const_int 3 [0x3]))
                     (reg/f:DI 1009 [880])))
             (set (mem:BLK (reg/f:DI 1008 [orig:490 <retval> ] [490]) 
[22 *_372+0 S1048 A64])
                 (mem/c:BLK (reg/f:DI 1009 [880]) [22 GOTMP.492+0 S1048 
A128]))
             (use (reg:DI 492))
         ]) 
"/opt/notnfs/msebor/src/gcc/82301/libgo/go/cmd/go/internal/load/pkg.go":679 
930 {*rep_movdi_rex64}
      (expr_list:REG_UNUSED (reg/f:DI 1009 [880])
         (expr_list:REG_UNUSED (reg/f:DI 1008 [orig:490 <retval> ] [490])
             (expr_list:REG_UNUSED (reg:DI 492)
                 (expr_list:REG_EH_REGION (const_int 1 [0x1])
                     (nil))))))
during RTL pass: reload

and in Ada:

s-stposu.adb:343:8: error: unable to find a register to spill
s-stposu.adb:343:8: error: this is the insn:
(insn 187 591 592 34 (parallel [
             (set (reg:SI 185 [156])
                 (div:SI (reg:SI 185 [156])
                     (mem/c:SI (plus:SI (reg/f:SI 16 argp)
                             (const_int 28 [0x1c])) [5 alignment+0 S4 
A32])))
             (set (reg:SI 158)
                 (mod:SI (reg:SI 185 [156])
                     (mem/c:SI (plus:SI (reg/f:SI 16 argp)
                             (const_int 28 [0x1c])) [5 alignment+0 S4 
A32])))
             (clobber (reg:CC 17 flags))
         ]) "s-stposu.adb":603 362 {*divmodsi4}
      (expr_list:REG_DEAD (reg:XF 16 argp)
         (expr_list:REG_UNUSED (reg:SI 158)
             (expr_list:REG_UNUSED (reg:CC 17 flags)
                 (expr_list:REG_EH_REGION (const_int 12 [0xc])
                     (nil))))))
+===========================GNAT BUG DETECTED==============================+
| 8.0.0 20171011 (experimental) (x86_64-pc-linux-gnu) GCC error:           |
| in assign_by_spills, at lra-assigns.c:1468                               |
| Error detected around s-stposu.adb:343:8                                 |
| Please submit a bug report; see https://gcc.gnu.org/bugs/ .              |
| Use a subject line meaningful to you and us to track the bug.            |
| Include the entire contents of this bug box in the report.               |
| Include the exact command that you entered.                              |
| Also include sources listed below.                                       |
+==========================================================================+