[Bug c/84903] New: internal compiler error: in convert_move, at expr.c:229

["marcin.krotkiewski at gmail dot com" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84903

            Bug ID: 84903
           Summary: internal compiler error: in convert_move, at
                    expr.c:229
           Product: gcc
           Version: 7.2.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
          Assignee: unassigned at gcc dot gnu.org
          Reporter: marcin.krotkiewski at gmail dot com
  Target Milestone: ---

Created attachment 43680
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=43680&action=edit
pre-processed source that triggers the error

The attached code fails to compile using gcc 7.2.0 (ubuntu 16.04 and centos
7.4.1708):

gcc -Wimplicit-fallthrough=0 -Wall -Wextra -save-temps -fopenmp -O3
-ftree-vectorize -ffast-math -c cop.c -o cop.o
cop.c: In function ‘HE1OP.simdclone.6’:
cop.c:21:8: internal compiler error: in convert_move, at expr.c:229
 double  HE1OP(double XHE1, double FREQ, double FREQLG, double TKEV, double
TLOG)
        ^~~~~
0x760b50 convert_move(rtx_def*, rtx_def*, int)
        ../../src/gcc/expr.c:229
0x7672b3 store_expr_with_bounds(tree_node*, rtx_def*, int, bool, bool,
tree_node*)
        ../../src/gcc/expr.c:5629
0x76775e expand_assignment(tree_node*, tree_node*, bool)
        ../../src/gcc/expr.c:5321
0x67a841 expand_call_stmt
        ../../src/gcc/cfgexpand.c:2656
0x67a841 expand_gimple_stmt_1
        ../../src/gcc/cfgexpand.c:3571
0x67a841 expand_gimple_stmt
        ../../src/gcc/cfgexpand.c:3737
0x67ba1f expand_gimple_basic_block
        ../../src/gcc/cfgexpand.c:5744
0x680ba6 execute
        ../../src/gcc/cfgexpand.c:6357
Please submit a full bug report,
with preprocessed source if appropriate.
Please include the complete backtrace with any bug report.
See <file:///usr/share/doc/gcc-7/README.Bugs> for instructions.


I tried on centos with gcc 6.4, and it also fails in the same way. The error is
not there if I do not try to generate an OpenMP-vectorized function, i.e., I
remove -fopenmp, -ffast-math, or the #pragma omp simd.

The attached is a simplest case I managed to get down to from the production
code I'm looking at.