re PR tree-optimization/19055 (Minor bit optimization with or and xor)

2005-07-21  Andrew Pinski  <pinskia@physics.uc.edu>

        PR middle-end/19055
        * gcc.dg/tree-ssa/pr19055.c: New test.
        * gcc.dg/tree-ssa/pr19055-2.c: New test.

2005-07-21  Andrew Pinski  <pinskia@physics.uc.edu>

        PR middle-end/19055
        * fold-const.c (fold_binary): Transform "(X | Y) ^ X" to "Y & ~ X".

From-SVN: r102243

gcc/ChangeLog

+2005-07-21  Andrew Pinski  <pinskia@physics.uc.edu>
+
+	PR middle-end/19055
+	* fold-const.c (fold_binary): Transform "(X | Y) ^ X" to "Y & ~ X".
+
 2005-07-21  Paolo Bonzini  <bonzini@gnu.org>
 
 	* common.opt (-fforward-propagate): Committed by mistake,

gcc/fold-const.c

@@ -8059,6 +8059,54 @@ fold_binary (enum tree_code code, tree type, tree op0, tree op1)
 	  goto bit_ior;
 	}
 
+      /* (X | Y) ^ X -> Y & ~ X*/
+      if (TREE_CODE (arg0) == BIT_IOR_EXPR
+          && operand_equal_p (TREE_OPERAND (arg0, 0), arg1, 0))
+        {
+	  tree t2 = TREE_OPERAND (arg0, 1);
+	  t1 = fold_build1 (BIT_NOT_EXPR, TREE_TYPE (arg1),
+			    arg1);
+	  t1 = fold_build2 (BIT_AND_EXPR, type, fold_convert (type, t2),
+			    fold_convert (type, t1));
+	  return t1;
+	}
+
+      /* (Y | X) ^ X -> Y & ~ X*/
+      if (TREE_CODE (arg0) == BIT_IOR_EXPR
+          && operand_equal_p (TREE_OPERAND (arg0, 1), arg1, 0))
+        {
+	  tree t2 = TREE_OPERAND (arg0, 0);
+	  t1 = fold_build1 (BIT_NOT_EXPR, TREE_TYPE (arg1),
+			    arg1);
+	  t1 = fold_build2 (BIT_AND_EXPR, type, fold_convert (type, t2),
+			    fold_convert (type, t1));
+	  return t1;
+	}
+
+      /* X ^ (X | Y) -> Y & ~ X*/
+      if (TREE_CODE (arg1) == BIT_IOR_EXPR
+          && operand_equal_p (TREE_OPERAND (arg1, 0), arg0, 0))
+        {
+	  tree t2 = TREE_OPERAND (arg1, 1);
+	  t1 = fold_build1 (BIT_NOT_EXPR, TREE_TYPE (arg0),
+			    arg0);
+	  t1 = fold_build2 (BIT_AND_EXPR, type, fold_convert (type, t2),
+			    fold_convert (type, t1));
+	  return t1;
+	}
+
+      /* X ^ (Y | X) -> Y & ~ X*/
+      if (TREE_CODE (arg1) == BIT_IOR_EXPR
+          && operand_equal_p (TREE_OPERAND (arg1, 1), arg0, 0))
+        {
+	  tree t2 = TREE_OPERAND (arg1, 0);
+	  t1 = fold_build1 (BIT_NOT_EXPR, TREE_TYPE (arg0),
+			    arg0);
+	  t1 = fold_build2 (BIT_AND_EXPR, type, fold_convert (type, t2),
+			    fold_convert (type, t1));
+	  return t1;
+	}
+	
       /* Convert ~X ^ ~Y to X ^ Y.  */
       if (TREE_CODE (arg0) == BIT_NOT_EXPR
 	  && TREE_CODE (arg1) == BIT_NOT_EXPR)

gcc/testsuite/ChangeLog

 2005-07-21  Andrew Pinski  <pinskia@physics.uc.edu>
 
+	PR middle-end/19055
+	* gcc.dg/tree-ssa/pr19055.c: New test.
+	* gcc.dg/tree-ssa/pr19055-2.c: New test.
+
+2005-07-21  Andrew Pinski  <pinskia@physics.uc.edu>
+
 	PR C++/22358
 	* g++.dg/other/pr22358.C: New test.