[Bug c/84987] New: ice in vectorizable_reduction with -O3

[dcb314 at hotmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84987

            Bug ID: 84987
           Summary: ice in vectorizable_reduction with -O3
           Product: gcc
           Version: 8.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
          Assignee: unassigned at gcc dot gnu.org
          Reporter: dcb314 at hotmail dot com
  Target Milestone: ---

Created attachment 43715
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=43715&action=edit
C source code

The attached C code seems to cause a crash with flag -O3:

$ ../results/bin/gcc -c -w -O3 bug423.c
during GIMPLE pass: vect
quvi.c: In function ‘main’:
quvi.c:1058:5: internal compiler error: Segmentation fault
0xdafbbf crash_signal
        ../../trunk/gcc/toplev.c:325
0x10b7566 tree_check(tree_node*, char const*, int, char const*, tree_code)
        ../../trunk/gcc/tree.h:3134
0x10b7566 vectorizable_reduction(gimple*, gimple_stmt_iterator*, gimple**,
_slp_tree*, _slp_instance*)
        ../../trunk/gcc/tree-vect-loop.c:6858
0x10aba9d vect_analyze_stmt(gimple*, bool*, _slp_tree*, _slp_instance*)
        ../../trunk/gcc/tree-vect-stmts.c:9378

This seems to have been happening since sometime before revision 257549.

I'll have a go at reducing the code.