[Bug target/71555] New: [7 Regression] ICE: compilation "never" finishes with -O -mtune=sandybridge -mavx512bw

["zsojka at seznam dot cz" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71555

            Bug ID: 71555
           Summary: [7 Regression] ICE: compilation "never" finishes with
                    -O -mtune=sandybridge -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 38710
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=38710&action=edit
reduced testcase

Compiler output:
$ x86_64-pc-linux-gnu-gcc -O -mtune=sandybridge -mavx512bw testcase.c
(nothing)

The cc1 process is slowly eating memory.

Backtrace:
(gdb) bt
#0  bitmap_set_bit (head=head@entry=0x7fffffffcfc0, bit=1153) at
/repo/gcc-trunk/gcc/bitmap.c:602
#1  0x0000000000a346f7 in assign_spill_hard_regs (n=1, pseudo_regnos=0x25f7260)
at /repo/gcc-trunk/gcc/lra-spills.c:275
#2  lra_spill () at /repo/gcc-trunk/gcc/lra-spills.c:587
#3  0x0000000000a0b2ad in lra (f=<optimized out>) at
/repo/gcc-trunk/gcc/lra.c:2380
#4  0x00000000009b24ba in do_reload () at /repo/gcc-trunk/gcc/ira.c:5384
#5  (anonymous namespace)::pass_reload::execute (this=<optimized out>) at
/repo/gcc-trunk/gcc/ira.c:5568
#6  0x0000000000ab8447 in execute_one_pass (pass=pass@entry=0x228db00) at
/repo/gcc-trunk/gcc/passes.c:2344
#7  0x0000000000ab8a18 in execute_pass_list_1 (pass=0x228db00) at
/repo/gcc-trunk/gcc/passes.c:2428
#8  0x0000000000ab8a2a in execute_pass_list_1 (pass=0x228ca80) at
/repo/gcc-trunk/gcc/passes.c:2429
#9  0x0000000000ab8a75 in execute_pass_list (fn=<optimized out>,
pass=<optimized out>) at /repo/gcc-trunk/gcc/passes.c:2439
#10 0x000000000076a554 in cgraph_node::expand (this=this@entry=0x7ffff6e4c000)
at /repo/gcc-trunk/gcc/cgraphunit.c:1983
#11 0x000000000076beaf in expand_all_functions () at
/repo/gcc-trunk/gcc/cgraphunit.c:2119
#12 symbol_table::compile (this=this@entry=0x7ffff6c580a8) at
/repo/gcc-trunk/gcc/cgraphunit.c:2475
#13 0x000000000076e18a in symbol_table::compile (this=0x7ffff6c580a8) at
/repo/gcc-trunk/gcc/cgraphunit.c:2568
#14 symbol_table::finalize_compilation_unit (this=0x7ffff6c580a8) at
/repo/gcc-trunk/gcc/cgraphunit.c:2565
#15 0x0000000000bc1fcb in compile_file () at /repo/gcc-trunk/gcc/toplev.c:490
#16 0x00000000005c92fa in do_compile () at /repo/gcc-trunk/gcc/toplev.c:1998
#17 toplev::main (this=this@entry=0x7fffffffd2e0, argc=<optimized out>,
argc@entry=16, argv=<optimized out>, argv@entry=0x7fffffffd3e8) at
/repo/gcc-trunk/gcc/toplev.c:2127
#18 0x00000000005cb2b7 in main (argc=16, argv=0x7fffffffd3e8) at
/repo/gcc-trunk/gcc/main.c:39