haifa-sched.c: make twins a auto_vec<rtx_insn *>

gcc/ChangeLog:

2016-07-28  Trevor Saunders  <tbsaunde+gcc@tbsaunde.org>

	* haifa-sched.c (add_to_speculative_block): Make twins a vector.

From-SVN: r238813

gcc/ChangeLog

 2016-07-28  Trevor Saunders  <tbsaunde+gcc@tbsaunde.org>
 
+	* haifa-sched.c (add_to_speculative_block): Make twins a vector.
+
+2016-07-28  Trevor Saunders  <tbsaunde+gcc@tbsaunde.org>
+
 	* store-motion.c (struct st_expr): Make pattern_regs a vector.
 	(extract_mentioned_regs): Append to a vector instead of
 	returning a rtx_expr_list.

gcc/haifa-sched.c

@@ -7991,7 +7991,7 @@ add_to_speculative_block (rtx_insn *insn)
   ds_t ts;
   sd_iterator_def sd_it;
   dep_t dep;
-  rtx_insn_list *twins = NULL;
+  auto_vec<rtx_insn *, 10> twins;
 
   ts = TODO_SPEC (insn);
   gcc_assert (!(ts & ~BE_IN_SPEC));
@@ -8060,7 +8060,7 @@ add_to_speculative_block (rtx_insn *insn)
         fprintf (spec_info->dump, ";;\t\tGenerated twin insn : %d/rec%d\n",
                  INSN_UID (twin), rec->index);
 
-      twins = alloc_INSN_LIST (twin, twins);
+      twins.safe_push (twin);
 
       /* Add dependences between TWIN and all appropriate
 	 instructions from REC.  */
@@ -8099,13 +8099,9 @@ add_to_speculative_block (rtx_insn *insn)
 
   /* We couldn't have added the dependencies between INSN and TWINS earlier
      because that would make TWINS appear in the INSN_BACK_DEPS (INSN).  */
-  while (twins)
-    {
+  unsigned int i;
   rtx_insn *twin;
-      rtx_insn_list *next_node;
-
-      twin = twins->insn ();
-
+  FOR_EACH_VEC_ELT_REVERSE (twins, i, twin)
     {
       dep_def _new_dep, *new_dep = &_new_dep;
 
@@ -8113,11 +8109,6 @@ add_to_speculative_block (rtx_insn *insn)
       sd_add_dep (new_dep, false);
     }
 
-      next_node = twins->next ();
-      free_INSN_LIST_node (twins);
-      twins = next_node;
-    }
-
   calc_priorities (priorities_roots);
 }