[Bug target/78669] New: ICE: in combine_and_move_insns, at ira.c:3665 with -Os -fno-tree-ter -mavx512bw

[zsojka at seznam dot cz]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78669

            Bug ID: 78669
           Summary: ICE: in combine_and_move_insns, at ira.c:3665 with -Os
                    -fno-tree-ter -mavx512bw
           Product: gcc
           Version: 7.0
            Status: UNCONFIRMED
          Keywords: ice-on-valid-code
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: zsojka at seznam dot cz
  Target Milestone: ---
              Host: x86_64-pc-linux-gnu
            Target: x86_64-pc-linux-gnu
             Build: x86_64-pc-linux-gnu

Created attachment 40239
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=40239&action=edit
reduced testcase

Compiler output:
$ x86_64-pc-linux-gnu-gcc -Os -fno-tree-ter -mavx512bw testcase.c
testcase.c: In function 'bar':
testcase.c:18:1: internal compiler error: in combine_and_move_insns, at
ira.c:3665
 }
 ^
0xa94929 combine_and_move_insns
        /repo/gcc-trunk/gcc/ira.c:3665
0xa9c1ed ira
        /repo/gcc-trunk/gcc/ira.c:5186
0xa9c1ed execute
        /repo/gcc-trunk/gcc/ira.c:5527
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.

$ x86_64-pc-linux-gnu-gcc -v
Using built-in specs.
COLLECT_GCC=/repo/gcc-trunk/binary-latest/bin/x86_64-pc-linux-gnu-gcc
COLLECT_LTO_WRAPPER=/repo/gcc-trunk/binary-trunk-243200-checking-yes-rtl-df-extra-nobootstrap-nographite-amd64/bin/../libexec/gcc/x86_64-pc-linux-gnu/7.0.0/lto-wrapper
Target: x86_64-pc-linux-gnu
Configured with: /repo/gcc-trunk//configure --enable-languages=c,c++
--enable-valgrind-annotations --disable-nls --enable-checking=yes,rtl,df,extra
--disable-bootstrap --without-cloog --without-ppl --without-isl
--build=x86_64-pc-linux-gnu --host=x86_64-pc-linux-gnu
--target=x86_64-pc-linux-gnu --with-ld=/usr/bin/x86_64-pc-linux-gnu-ld
--with-as=/usr/bin/x86_64-pc-linux-gnu-as --disable-libstdcxx-pch
--prefix=/repo/gcc-trunk//binary-trunk-243200-checking-yes-rtl-df-extra-nobootstrap-nographite-amd64
Thread model: posix
gcc version 7.0.0 20161202 (experimental) (GCC) 

Tested revisions:
r243200 - FAIL
r242857 - FAIL
r242657 - OK
r242541 - OK