re PR tree-optimization/24575 (-(i /10) is not foldded to i/-10)

2005-11-27  Andrew Pinski  <pinskia@physics.uc.edu>

        PR middle-end/24575
        * fold-const.c (negate_expr_p): Add case for signed divides if overflow
        is undefined.
        (negate_expr): Likewise.
2005-11-27  Andrew Pinski  <pinskia@physics.uc.edu>

        PR middle-end/24575
        * gcc.dg/tree-ssa/divide-3.c: New test.
        * gcc.dg/tree-ssa/divide-4.c: New test.

From-SVN: r107575

gcc/ChangeLog

+2005-11-27  Andrew Pinski  <pinskia@physics.uc.edu>
+
+	PR middle-end/24575
+	* fold-const.c (negate_expr_p): Add case for signed divides if overflow
+	is undefined.
+	(negate_expr): Likewise.
+
 2005-11-27  Andreas Schwab  <schwab@suse.de>
 
 	* config/m68k/m68k.c: Reindent and fix whitespace, remove

gcc/fold-const.c

@@ -991,6 +991,16 @@ negate_expr_p (tree t)
 	       || negate_expr_p (TREE_OPERAND (t, 0));
       break;
 
+    case TRUNC_DIV_EXPR:
+    case ROUND_DIV_EXPR:
+    case FLOOR_DIV_EXPR:
+    case CEIL_DIV_EXPR:
+    case EXACT_DIV_EXPR:
+      if (TYPE_UNSIGNED (TREE_TYPE (t)) || flag_wrapv)
+        break;
+      return negate_expr_p (TREE_OPERAND (t, 1))
+             || negate_expr_p (TREE_OPERAND (t, 0));
+
     case NOP_EXPR:
       /* Negate -((double)float) as (double)(-float).  */
       if (TREE_CODE (type) == REAL_TYPE)
@@ -1132,6 +1142,28 @@ negate_expr (tree t)
 	}
       break;
 
+    case TRUNC_DIV_EXPR:
+    case ROUND_DIV_EXPR:
+    case FLOOR_DIV_EXPR:
+    case CEIL_DIV_EXPR:
+    case EXACT_DIV_EXPR:
+      if (!TYPE_UNSIGNED (TREE_TYPE (t)) && !flag_wrapv)
+        {
+          tem = TREE_OPERAND (t, 1);
+          if (negate_expr_p (tem))
+            return fold_convert (type,
+                                 fold_build2 (TREE_CODE (t), TREE_TYPE (t),
+                                              TREE_OPERAND (t, 0),
+                                              negate_expr (tem)));
+          tem = TREE_OPERAND (t, 0);
+          if (negate_expr_p (tem))
+            return fold_convert (type,
+                                 fold_build2 (TREE_CODE (t), TREE_TYPE (t),
+                                              negate_expr (tem),
+                                              TREE_OPERAND (t, 1)));
+        }
+      break;
+
     case NOP_EXPR:
       /* Convert -((double)float) into (double)(-float).  */
       if (TREE_CODE (type) == REAL_TYPE)

gcc/testsuite/ChangeLog

+2005-11-27  Andrew Pinski  <pinskia@physics.uc.edu>
+
+	PR middle-end/24575
+	* gcc.dg/tree-ssa/divide-3.c: New test.
+	* gcc.dg/tree-ssa/divide-4.c: New test.
+
 2005-11-27  Steven G. Kargl  <kargls@comcast.net>
 
 	PR fortran/24917

gcc/testsuite/gcc.dg/tree-ssa/divide-3.c

+/* { dg-do compile } */
+/* { dg-options "-O1 -fdump-tree-optimized" } */
+
+int f(int a)
+{
+  return -(a/10);
+}
+
+/* { dg-final { scan-tree-dump-times "a / 10" 0 "optimized"} } */
+/* { dg-final { scan-tree-dump-times "a / -10" 1 "optimized"} } */
+
+/* { dg-final { cleanup-tree-dump "optimized" } } */
+
+

gcc/testsuite/gcc.dg/tree-ssa/divide-4.c

+/* { dg-do compile } */
+/* { dg-options "-O1 -fdump-tree-optimized" } */
+
+int f(int a)
+{
+  return -(-a/10);
+}
+
+/* { dg-final { scan-tree-dump-times "-a / 10" 0 "optimized"} } */
+/* { dg-final { scan-tree-dump-times "a / 10" 1 "optimized"} } */
+
+/* { dg-final { cleanup-tree-dump "optimized" } } */
+
+