patch to fix PR55050 and PR55068

[Vladimir Makarov]

The following patch is to solve

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55050
and probably

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55068

Code updating equivalences was added to IRA.  It was supposed for LRA.  
It might create problems for reload because it creates inconsistency in 
dealing with equivs in reload and IRA.

The patch was successfully bootstrapped on x86/x86-64.

Committed as rev. 192797.

2012-10-24  Vladimir Makarov  <vmaka...@redhat.com>

    PR bootstrap/55068
    PR regression/55050
    * ira.c (setup_reg_renumber): Fix assert.
    * ira-emit.c (emit_move_list): Update equivalences only for LRA.

Index: ira.c
===================================================================
--- ira.c       (revision 192742)
+++ ira.c       (working copy)
@@ -1989,6 +1989,7 @@ setup_reg_renumber (void)
              ira_assert (!optimize || flag_caller_saves
                          || (ALLOCNO_CALLS_CROSSED_NUM (a)
                              == ALLOCNO_CHEAP_CALLS_CROSSED_NUM (a))
+                         || regno >= ira_reg_equiv_len
                          || ira_equiv_no_lvalue_p (regno));
              caller_save_needed = 1;
            }
Index: ira-emit.c
===================================================================
--- ira-emit.c  (revision 192742)
+++ ira-emit.c  (working copy)
@@ -947,7 +947,8 @@ emit_move_list (move_t list, int freq)
                = gen_rtx_INSN_LIST (VOIDmode, insn, reg_equiv_init (regno));
            }
        }
-      ira_update_equiv_info_by_shuffle_insn (to_regno, from_regno, list->insn);
+      if (ira_use_lra_p)
+       ira_update_equiv_info_by_shuffle_insn (to_regno, from_regno, 
list->insn);
       emit_insn (list->insn);
       mode = ALLOCNO_MODE (list->to);
       aclass = ALLOCNO_CLASS (list->to);