[Bug target/59605] [4.9 Regression] error: wrong number of branch edges after unconditional jump in bb 11

["hjl.tools at gmail dot com" <gcc-bugzilla at gcc dot gnu dot org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=59605

H.J. Lu <hjl.tools at gmail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2013-12-26
     Ever confirmed|0                           |1

--- Comment #2 from H.J. Lu <hjl.tools at gmail dot com> ---
ix86_expand_set_or_movmem has

  rtx jump_around_label = NULL;

 /* Misaligned move sequences handles both prologues and epilogues at once.
     Default code generation results in smaller code for large alignments and
     also avoids redundant job when sizes are known precisely.  */
  if (misaligned_prologue_used)
    {
      /* Misaligned move prologue handled small blocks by itself.  */
      expand_set_or_movmem_prologue_epilogue_by_misaligned_moves
           (dst, src, &destreg, &srcreg,
            move_mode, promoted_val, vec_promoted_val,
            &count_exp,
            &jump_around_label,
            desired_align < align
            ? MAX (desired_align, epilogue_size_needed) : epilogue_size_needed,
            desired_align, align, &min_size, dynamic_check, issetmem);
      if (!issetmem)
        src = change_address (src, BLKmode, srcreg);
...
      else
        {   
          rtx hot_label = gen_label_rtx ();
          jump_around_label = gen_label_rtx ();
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
When jump_around_label != NULL, the previous jump_around_label
is lost.
          emit_cmp_and_jump_insns (count_exp, GEN_INT (dynamic_check - 1),
                                   LEU, 0, GET_MODE (count_exp), 1, hot_label);
          predict_jump (REG_BR_PROB_BASE * 90 / 100);
          if (issetmem)
            set_storage_via_libcall (dst, count_exp, val_exp, false);
          else
            emit_block_move_via_libcall (dst, src, count_exp, false);
          emit_jump (jump_around_label);
          emit_label (hot_label);
        }