[Bug target/63910] New: [5 Regression] ICE: simplify_immed_subreg, at simplify-rtx.c:5519 with -mstringop-strategy=vector_loop -mavx512f

[zsojka at seznam dot cz]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63910

            Bug ID: 63910
           Summary: [5 Regression] ICE: simplify_immed_subreg, at
                    simplify-rtx.c:5519 with
                    -mstringop-strategy=vector_loop -mavx512f
           Product: gcc
           Version: 5.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: zsojka at seznam dot cz

Created attachment 33999
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=33999&action=edit
reduced testcase

Compiler output:
$ gcc -O -mstringop-strategy=vector_loop -mavx512f testcase.c 
testcase.c: In function 'foo':
testcase.c:8:1: internal compiler error: in simplify_immed_subreg, at
simplify-rtx.c:5519
 }
 ^
0xc331ee simplify_immed_subreg
        /mnt/svn/gcc-trunk/gcc/simplify-rtx.c:5519
0xc48509 simplify_gen_subreg(machine_mode, rtx_def*, machine_mode, unsigned
int)
        /mnt/svn/gcc-trunk/gcc/simplify-rtx.c:5818
0x165f75c propagate_rtx_1
        /mnt/svn/gcc-trunk/gcc/fwprop.c:550
0x166014f propagate_rtx
        /mnt/svn/gcc-trunk/gcc/fwprop.c:686
0x1661f63 forward_propagate_and_simplify
        /mnt/svn/gcc-trunk/gcc/fwprop.c:1333
0x1661f63 forward_propagate_into
        /mnt/svn/gcc-trunk/gcc/fwprop.c:1391
0x1662c84 fwprop
        /mnt/svn/gcc-trunk/gcc/fwprop.c:1476
0x1662c84 execute
        /mnt/svn/gcc-trunk/gcc/fwprop.c:1509
Please submit a full bug report,
with preprocessed source if appropriate.
Please include the complete backtrace with any bug report.
See <http://gcc.gnu.org/bugs.html> for instructions.


Tested revisions:
r217624 - ICE
4_9 r216937 - OK