tree-ssa-dom.c (simplify_rhs_and_lookup_avail_expr): Reorganize so that it picks…

tree-ssa-dom.c (simplify_rhs_and_lookup_avail_expr): Reorganize so that it picks up more opportunities to eliminate ABS expressions...

        * tree-ssa-dom.c (simplify_rhs_and_lookup_avail_expr): Reorganize
        so that it picks up more opportunities to eliminate ABS expressions
        or turn them into negations.

        * gcc.dg/tree-ssa/20040514-2.c: New test.

From-SVN: r81853

gcc/ChangeLog

+2004-05-14  Jeff Law  <law@redhat.com>
+
+	* tree-ssa-dom.c (simplify_rhs_and_lookup_avail_expr): Reorganize
+	so that it picks up more opportunities to eliminate ABS expressions
+	or turn them into negations.
+
 2004-05-14  Steven Bosscher  <stevenb@suse.de>
 
 	* passes.c (rest_of_handle_null_pointer): Remove.

gcc/testsuite/ChangeLog

+2004-05-14  Jeff Law  <law@redhat.com>
+
+	* gcc.dg/tree-ssa/20040514-2.c: New test.
+
 2004-05-14  Tobias Schlueter  <tobias.schlueter@physik.uni-muenchen.de>
 
 	* gfortran.fortran-torture/compile/noncontinuation_1.f90: Rename

gcc/testsuite/gcc.dg/tree-ssa/20040514-2.c

+/* { dg-do compile } */
+/* { dg-options "-O1 -fdump-tree-dom3" } */
+int
+foo2 (distance, i, j)
+     int distance;
+     int i, j;
+{
+ int t = distance;
+ if (t <= 0)
+   t = ((t) >= 0 ? (t)  : -(t));
+ return t;
+}
+
+/* There should be no ABS_EXPR.  */
+/* { dg-final { scan-tree-dump-times "ABS_EXPR " 0 "dom3"} } */

gcc/tree-ssa-dom.c

@@ -1826,7 +1826,7 @@ simplify_rhs_and_lookup_avail_expr (struct dom_walk_data *walk_data,
 
 	  if (! dummy_cond)
 	    {
-	      dummy_cond = build (LT_EXPR, boolean_type_node,
+	      dummy_cond = build (LE_EXPR, boolean_type_node,
 				  op, integer_zero_node);
 	      dummy_cond = build (COND_EXPR, void_type_node,
 				  dummy_cond, NULL, NULL);
@@ -1834,7 +1834,7 @@ simplify_rhs_and_lookup_avail_expr (struct dom_walk_data *walk_data,
 	    }
 	  else
 	    {
-	      TREE_SET_CODE (TREE_OPERAND (dummy_cond, 0), LT_EXPR);
+	      TREE_SET_CODE (TREE_OPERAND (dummy_cond, 0), LE_EXPR);
 	      TREE_OPERAND (TREE_OPERAND (dummy_cond, 0), 0) = op;
 	      TREE_OPERAND (TREE_OPERAND (dummy_cond, 0), 1)
 		= convert (type, integer_zero_node);
@@ -1842,6 +1842,26 @@ simplify_rhs_and_lookup_avail_expr (struct dom_walk_data *walk_data,
 	  val = simplify_cond_and_lookup_avail_expr (dummy_cond,
 						     &bd->avail_exprs,
 						     NULL, false);
+
+	  if (!val)
+	    {
+	      TREE_SET_CODE (TREE_OPERAND (dummy_cond, 0), GE_EXPR);
+	      TREE_OPERAND (TREE_OPERAND (dummy_cond, 0), 0) = op;
+	      TREE_OPERAND (TREE_OPERAND (dummy_cond, 0), 1)
+		= convert (type, integer_zero_node);
+
+	      val = simplify_cond_and_lookup_avail_expr (dummy_cond,
+							 &bd->avail_exprs,
+							 NULL, false);
+
+	      if (val)
+		{
+		  if (integer_zerop (val))
+		    val = integer_one_node;
+		  else if (integer_onep (val))
+		    val = integer_zero_node;
+		}
+	    }
 	}
 
       if (val