[Bug rtl-optimization/50765] [4.7 Regression] ICE: in expand_insn, at optabs.c:7681 with -ftree-vectorize -fno-tree-dce

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50765

Richard Guenther <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Priority|P3                          |P1
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2011-10-27
     Ever Confirmed|0                           |1

--- Comment #1 from Richard Guenther <rguenth at gcc dot gnu.org> 2011-10-27 11:11:15 UTC ---
Confirmed.

#2  0x0000000000a41dad in expand_insn (icode=CODE_FOR_vec_unpacks_lo_v4si, 
    nops=2, ops=0x7fffffffcb60)
    at /space/rguenther/src/svn/trunk/gcc/optabs.c:7824
7824        gcc_unreachable ();
(gdb) l
7819    void
7820    expand_insn (enum insn_code icode, unsigned int nops,
7821                 struct expand_operand *ops)
7822    {
7823      if (!maybe_expand_insn (icode, nops, ops))
7824        gcc_unreachable ();

It seems we expand some useless unpacking?