[PATCH 07/18] loop-iv.c: make cond_list a vec

[tbsaunde+gcc at tbsaunde dot org]

From: Trevor Saunders <tbsaunde+gcc@tbsaunde.org>

gcc/ChangeLog:

2016-04-19  Trevor Saunders  <tbsaunde+gcc@tbsaunde.org>

	* loop-iv.c (simplify_using_initial_values): Make cond_list a vector.
---
 gcc/loop-iv.c | 55 ++++++++++++++++++-------------------------------------
 1 file changed, 18 insertions(+), 37 deletions(-)

diff --git a/gcc/loop-iv.c b/gcc/loop-iv.c
index fecaf8f..7f000c7 100644
--- a/gcc/loop-iv.c
+++ b/gcc/loop-iv.c
@@ -1860,7 +1860,6 @@ simplify_using_initial_values (struct loop *loop, enum rtx_code op, rtx *expr)
 {
   bool expression_valid;
   rtx head, tail, last_valid_expr;
-  rtx_expr_list *cond_list;
   rtx_insn *insn;
   rtx neutral, aggr;
   regset altered, this_altered;
@@ -1936,7 +1935,7 @@ simplify_using_initial_values (struct loop *loop, enum rtx_code op, rtx *expr)
 
   expression_valid = true;
   last_valid_expr = *expr;
-  cond_list = NULL;
+  auto_vec<rtx> cond_list;
   while (1)
     {
       insn = BB_END (e->src);
@@ -1952,17 +1951,18 @@ simplify_using_initial_values (struct loop *loop, enum rtx_code op, rtx *expr)
 	      simplify_using_condition (cond, expr, altered);
 	      if (old != *expr)
 		{
-		  rtx note;
 		  if (CONSTANT_P (*expr))
 		    goto out;
-		  for (note = cond_list; note; note = XEXP (note, 1))
+
+		  unsigned int len = cond_list.length ();
+		  for (unsigned int i = len - 1; i < len; i--)
 		    {
-		      simplify_using_condition (XEXP (note, 0), expr, altered);
+		      simplify_using_condition (cond_list[i], expr, altered);
 		      if (CONSTANT_P (*expr))
 			goto out;
 		    }
 		}
-	      cond_list = alloc_EXPR_LIST (0, cond, cond_list);
+	      cond_list.safe_push (cond);
 	    }
 	}
 
@@ -1988,39 +1988,30 @@ simplify_using_initial_values (struct loop *loop, enum rtx_code op, rtx *expr)
 
 	  if (suitable_set_for_replacement (insn, &dest, &src))
 	    {
-	      rtx_expr_list **pnote, **pnote_next;
-
 	      replace_in_expr (expr, dest, src);
 	      if (CONSTANT_P (*expr))
 		goto out;
 
-	      for (pnote = &cond_list; *pnote; pnote = pnote_next)
+	      unsigned int len = cond_list.length ();
+	      for (unsigned int i = len - 1; i < len; i--)
 		{
-		  rtx_expr_list *note = *pnote;
-		  rtx old_cond = XEXP (note, 0);
+		  rtx old_cond = cond_list[i];
 
-		  pnote_next = (rtx_expr_list **)&XEXP (note, 1);
-		  replace_in_expr (&XEXP (note, 0), dest, src);
+		  replace_in_expr (&cond_list[i], dest, src);
 
 		  /* We can no longer use a condition that has been simplified
 		     to a constant, and simplify_using_condition will abort if
 		     we try.  */
-		  if (CONSTANT_P (XEXP (note, 0)))
-		    {
-		      *pnote = *pnote_next;
-		      pnote_next = pnote;
-		      free_EXPR_LIST_node (note);
-		    }
+		  if (CONSTANT_P (cond_list[i]))
+		    cond_list.ordered_remove (i);
 		  /* Retry simplifications with this condition if either the
 		     expression or the condition changed.  */
-		  else if (old_cond != XEXP (note, 0) || old != *expr)
-		    simplify_using_condition (XEXP (note, 0), expr, altered);
+		  else if (old_cond != cond_list[i] || old != *expr)
+		    simplify_using_condition (cond_list[i], expr, altered);
 		}
 	    }
 	  else
 	    {
-	      rtx_expr_list **pnote, **pnote_next;
-
 	      /* If we did not use this insn to make a replacement, any overlap
 		 between stores in this insn and our expression will cause the
 		 expression to become invalid.  */
@@ -2028,19 +2019,10 @@ simplify_using_initial_values (struct loop *loop, enum rtx_code op, rtx *expr)
 		goto out;
 
 	      /* Likewise for the conditions.  */
-	      for (pnote = &cond_list; *pnote; pnote = pnote_next)
-		{
-		  rtx_expr_list *note = *pnote;
-		  rtx old_cond = XEXP (note, 0);
-
-		  pnote_next = (rtx_expr_list **)&XEXP (note, 1);
-		  if (altered_reg_used (old_cond, this_altered))
-		    {
-		      *pnote = *pnote_next;
-		      pnote_next = pnote;
-		      free_EXPR_LIST_node (note);
-		    }
-		}
+	      unsigned int len = cond_list.length ();
+	      for (unsigned int i = len - 1; i < len; i--)
+		if (altered_reg_used (cond_list[i], this_altered))
+		  cond_list.ordered_remove (i);
 	    }
 
 	  if (CONSTANT_P (*expr))
@@ -2065,7 +2047,6 @@ simplify_using_initial_values (struct loop *loop, enum rtx_code op, rtx *expr)
     }
 
  out:
-  free_EXPR_LIST_list (&cond_list);
   if (!CONSTANT_P (*expr))
     *expr = last_valid_expr;
   FREE_REG_SET (altered);
-- 
2.7.4