[Bug middle-end/68852] New: [6 Regression] ICE in vect_is_simple_use (tree-vect-stmts.c:8750) using -O3

["marxin at gcc dot gnu.org" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68852

            Bug ID: 68852
           Summary: [6 Regression] ICE in vect_is_simple_use
                    (tree-vect-stmts.c:8750) using -O3
           Product: gcc
           Version: 6.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: middle-end
          Assignee: unassigned at gcc dot gnu.org
          Reporter: marxin at gcc dot gnu.org
  Target Milestone: ---

Created attachment 36991
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=36991&action=edit
test-case

Starting from r230993:

Author: rguenth <rguenth@138bc75d-0d04-0410-961f-82ee72b054a4>
Date:   Fri Nov 27 08:31:44 2015 +0000

    2015-11-27  Richard Biener  <rguenther@suse.de>

        PR tree-optimization/68553
        * tree-vect-slp.c (vect_get_mask_element): Remove.
        (vect_transform_slp_perm_load): Implement in a simpler way.

        * gcc.dg/vect/pr45752.c: Adjust.
        * gcc.dg/vect/slp-perm-4.c: Likewise.

I see ICE in tree-vect-stmts.c:8750:

$ ./xgcc -B. -O3 ~/Programming/testcases/tree-vect-stmts-ice/vect-ice.ii -c
/home/marxin/Programming/testcases/tree-vect-stmts-ice/vect-ice.ii: In function
âvoid fn1()â:
/home/marxin/Programming/testcases/tree-vect-stmts-ice/vect-ice.ii:46:6:
internal compiler error: in vect_is_simple_use, at tree-vect-stmts.c:8750
 void fn1() {
      ^~~

0xf28870 vect_is_simple_use(tree_node*, vec_info*, gimple**, vect_def_type*,
tree_node**)
        ../../gcc/tree-vect-stmts.c:8750
0xf2f143 vectorizable_operation
        ../../gcc/tree-vect-stmts.c:4874
0xf3e2f7 vect_analyze_stmt(gimple*, bool*, _slp_tree*)
        ../../gcc/tree-vect-stmts.c:8090
0xf57192 vect_slp_analyze_node_operations
        ../../gcc/tree-vect-slp.c:2205
0xf57113 vect_slp_analyze_node_operations
        ../../gcc/tree-vect-slp.c:2196
0xf583cc vect_slp_analyze_operations(vec<_slp_instance*, va_heap, vl_ptr>,
void*)
        ../../gcc/tree-vect-slp.c:2228
0xf5d35c vect_slp_analyze_bb_1
        ../../gcc/tree-vect-slp.c:2511
0xf5d35c vect_slp_bb(basic_block_def*)
        ../../gcc/tree-vect-slp.c:2598
0xf5f4b5 execute
        ../../gcc/tree-vectorizer.c:759

Thanks,
Martin