tree-vrp.c (stmt_interesting_for_vrp): Some statements with virtual operands are interesting.

	* tree-vrp.c (stmt_interesting_for_vrp): Some statements with
	virtual operands are interesting.
	(vrp_visit_stmt): Corresponding changes.

	* gcc.dg/tree-ssa/20030807-2.c: No longer expected to fail.

From-SVN: r112011

gcc/ChangeLog

+2006-03-13  Jeff Law  <law@redhat.com>
+
+	* tree-vrp.c (stmt_interesting_for_vrp): Some statements with
+	virtual operands are interesting.
+	(vrp_visit_stmt): Corresponding changes.
+
 2006-03-13  Bernd Schmidt  <bernd.schmidt@analog.com>
 
 	* config/bfin/lib1funcs.asm (___umodsi3): Use stack to save contents

gcc/testsuite/ChangeLog

+2006-03-13  Jeff Law  <law@redhat.com>
+
+	* gcc.dg/tree-ssa/20030807-2.c: No longer expected to fail.
+
 2006-03-13  Eric Botcazou  <ebotcazou@adacore.com>
 
 	* gcc.dg/switch-9.c: New test.

gcc/testsuite/gcc.dg/tree-ssa/20030807-2.c

@@ -24,5 +24,5 @@ foo(int n)
 
                                                                                
 /* There should be no IF conditionals.  */
-/* { dg-final { scan-tree-dump-times "if " 0 "dom3" { xfail *-*-* } } } */
+/* { dg-final { scan-tree-dump-times "if " 0 "dom3" } } */
 /* { dg-final { cleanup-tree-dump "dom3" } } */

gcc/tree-vrp.c

@@ -3266,11 +3266,19 @@ stmt_interesting_for_vrp (tree stmt)
   else if (TREE_CODE (stmt) == MODIFY_EXPR)
     {
       tree lhs = TREE_OPERAND (stmt, 0);
+      tree rhs = TREE_OPERAND (stmt, 1);
 
+      /* In general, assignments with virtual operands are not useful
+	 for deriving ranges, with the obvious exception of calls to
+	 builtin functions.  */
       if (TREE_CODE (lhs) == SSA_NAME
 	  && (INTEGRAL_TYPE_P (TREE_TYPE (lhs))
 	      || POINTER_TYPE_P (TREE_TYPE (lhs)))
-	  && ZERO_SSA_OPERANDS (stmt, SSA_OP_ALL_VIRTUALS))
+	  && ((TREE_CODE (rhs) == CALL_EXPR
+	       && TREE_CODE (TREE_OPERAND (rhs, 0)) == ADDR_EXPR
+	       && DECL_P (TREE_OPERAND (TREE_OPERAND (rhs, 0), 0))
+	       && DECL_IS_BUILTIN (TREE_OPERAND (TREE_OPERAND (rhs, 0), 0)))
+	      || ZERO_SSA_OPERANDS (stmt, SSA_OP_ALL_VIRTUALS)))
 	return true;
     }
   else if (TREE_CODE (stmt) == COND_EXPR || TREE_CODE (stmt) == SWITCH_EXPR)
@@ -3739,9 +3747,20 @@ vrp_visit_stmt (tree stmt, edge *taken_edge_p, tree *output_p)
     }
 
   ann = stmt_ann (stmt);
-  if (TREE_CODE (stmt) == MODIFY_EXPR
-      && ZERO_SSA_OPERANDS (stmt, SSA_OP_ALL_VIRTUALS))
-    return vrp_visit_assignment (stmt, output_p);
+  if (TREE_CODE (stmt) == MODIFY_EXPR)
+    {
+      tree rhs = TREE_OPERAND (stmt, 1);
+
+      /* In general, assignments with virtual operands are not useful
+	 for deriving ranges, with the obvious exception of calls to
+	 builtin functions.  */
+      if ((TREE_CODE (rhs) == CALL_EXPR
+	   && TREE_CODE (TREE_OPERAND (rhs, 0)) == ADDR_EXPR
+	   && DECL_P (TREE_OPERAND (TREE_OPERAND (rhs, 0), 0))
+	   && DECL_IS_BUILTIN (TREE_OPERAND (TREE_OPERAND (rhs, 0), 0)))
+	  || ZERO_SSA_OPERANDS (stmt, SSA_OP_ALL_VIRTUALS))
+	return vrp_visit_assignment (stmt, output_p);
+    }
   else if (TREE_CODE (stmt) == COND_EXPR || TREE_CODE (stmt) == SWITCH_EXPR)
     return vrp_visit_cond_stmt (stmt, taken_edge_p);