ChangeLog gcc/

2011-04-20  Kai Tietz  <ktietz@redhat.com>

	* fold-const.c (fold_binary_loc): Add handling for
	(X & ~Y) | (~X & Y) and (X && !Y) | (!X && Y) optimization
	to (X ^ Y).

ChangeLog gcc/testsuite

2011-04-20  Kai Tietz  <ktietz@redhat.com>

	* gcc.dg/binio-xor1.c: New test.
	* gcc.dg/binio-xor2.c: New test.
	* gcc.dg/binio-xor3.c: New test.
	* gcc.dg/binio-xor4.c: New test.
	* gcc.dg/binio-xor5.c: New test.

From-SVN: r172776

8 files changed, 128 insertions, 0 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index d64225c..cdb4d3b 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2011-04-20  Kai Tietz  <ktietz@redhat.com>
+
+	* fold-const.c (fold_binary_loc): Add handling for
+	(X & ~Y) | (~X & Y) and (X && !Y) | (!X && Y) optimization
+	to (X ^ Y).
+
 2011-04-20  Andrew Stubbs  <ams@codesourcery.com>
 
 	* config/arm/arm.c (arm_gen_constant): Remove redundant can_invert.
diff --git a/gcc/fold-const.c b/gcc/fold-const.c
index 8d543c4..c4bf088 100644
--- a/gcc/fold-const.c
+++ b/gcc/fold-const.c
@@ -10660,6 +10660,28 @@ fold_binary_loc (location_t loc,
 	  && reorder_operands_p (arg0, TREE_OPERAND (arg1, 0)))
 	return omit_one_operand_loc (loc, type, arg0, TREE_OPERAND (arg1, 0));
 
+      /* (X & ~Y) | (~X & Y) is X ^ Y */
+      if (TREE_CODE (arg0) == BIT_AND_EXPR
+	  && TREE_CODE (arg1) == BIT_AND_EXPR)
+        {
+	  tree a0, a1, l0, l1, n0, n1;
+
+	  a0 = fold_convert_loc (loc, type, TREE_OPERAND (arg1, 0));
+	  a1 = fold_convert_loc (loc, type, TREE_OPERAND (arg1, 1));
+
+	  l0 = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0));
+	  l1 = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 1));
+	  
+	  n0 = fold_build1_loc (loc, BIT_NOT_EXPR, type, l0);
+	  n1 = fold_build1_loc (loc, BIT_NOT_EXPR, type, l1);
+	  
+	  if ((operand_equal_p (n0, a0, 0)
+	       && operand_equal_p (n1, a1, 0))
+	      || (operand_equal_p (n0, a1, 0)
+		  && operand_equal_p (n1, a0, 0)))
+	    return fold_build2_loc (loc, BIT_XOR_EXPR, type, l0, n1);
+	}
+
       t1 = distribute_bit_expr (loc, code, type, arg0, arg1);
       if (t1 != NULL_TREE)
 	return t1;
@@ -12039,6 +12061,27 @@ fold_binary_loc (location_t loc,
 	  && operand_equal_p (arg0, TREE_OPERAND (arg1, 0), 0))
 	return omit_one_operand_loc (loc, type, integer_one_node, arg0);
 
+      /* (X && !Y) || (!X && Y) is X ^ Y */
+      if (TREE_CODE (arg0) == TRUTH_AND_EXPR
+	  && TREE_CODE (arg1) == TRUTH_AND_EXPR)
+        {
+	  tree a0, a1, l0, l1, n0, n1;
+
+	  a0 = fold_convert_loc (loc, type, TREE_OPERAND (arg1, 0));
+	  a1 = fold_convert_loc (loc, type, TREE_OPERAND (arg1, 1));
+
+	  l0 = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 0));
+	  l1 = fold_convert_loc (loc, type, TREE_OPERAND (arg0, 1));
+	  
+	  n0 = fold_build1_loc (loc, TRUTH_NOT_EXPR, type, l0);
+	  n1 = fold_build1_loc (loc, TRUTH_NOT_EXPR, type, l1);
+	  
+	  if ((operand_equal_p (n0, a0, 0)
+	       && operand_equal_p (n1, a1, 0))
+	      || (operand_equal_p (n0, a1, 0)
+		  && operand_equal_p (n1, a0, 0)))
+	    return fold_build2_loc (loc, TRUTH_XOR_EXPR, type, l0, n1);
+	}
       goto truth_andor;
 
     case TRUTH_XOR_EXPR:
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 5c792f1..95646de 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,11 @@
+2011-04-20  Kai Tietz  <ktietz@redhat.com>
+
+	* gcc.dg/binio-xor1.c: New test.
+	* gcc.dg/binio-xor2.c: New test.
+	* gcc.dg/binio-xor3.c: New test.
+	* gcc.dg/binio-xor4.c: New test.
+	* gcc.dg/binio-xor5.c: New test.
+
 2011-04-20  Richard Guenther  <rguenther@suse.de>
 
 	PR tree-optimization/47892
diff --git a/gcc/testsuite/gcc.dg/binop-xor1.c b/gcc/testsuite/gcc.dg/binop-xor1.c
new file mode 100644
index 0000000..7e46286
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/binop-xor1.c
@@ -0,0 +1,14 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -fdump-tree-optimized" } */
+
+int
+foo (int a, int b, int c)
+{
+  return ((a && !b && c) || (!a && b && c));
+}
+
+/* We expect to see "<bb N>"; confirm that, so that we know to count
+   it in the real test.  */
+/* { dg-final { scan-tree-dump-times "<bb\[^>\]*>" 5 "optimized" } } */
+/* { dg-final { scan-tree-dump-times "\^" 1 "optimized" } } */
+/* { dg-final { cleanup-tree-dump "optimized" } } */
diff --git a/gcc/testsuite/gcc.dg/binop-xor2.c b/gcc/testsuite/gcc.dg/binop-xor2.c
new file mode 100644
index 0000000..369b350
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/binop-xor2.c
@@ -0,0 +1,14 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -fdump-tree-optimized" } */
+
+int
+foo (int a, int b)
+{
+  return ((a & ~b) | (~a & b));
+}
+
+/* We expect to see "<bb N>"; confirm that, so that we know to count
+   it in the real test.  */
+/* { dg-final { scan-tree-dump-times "<bb\[^>\]*>" 1 "optimized" } } */
+/* { dg-final { scan-tree-dump-times "\^" 1 "optimized" } } */
+/* { dg-final { cleanup-tree-dump "optimized" } } */
diff --git a/gcc/testsuite/gcc.dg/binop-xor3.c b/gcc/testsuite/gcc.dg/binop-xor3.c
new file mode 100644
index 0000000..ef4b82f
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/binop-xor3.c
@@ -0,0 +1,14 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -fdump-tree-optimized" } */
+
+int
+foo (int a, int b)
+{
+  return ((a && !b) || (!a && b));
+}
+
+/* We expect to see "<bb N>"; confirm that, so that we know to count
+   it in the real test.  */
+/* { dg-final { scan-tree-dump-times "<bb\[^>\]*>" 1 "optimized" } } */
+/* { dg-final { scan-tree-dump-times "\^" 1 "optimized" } } */
+/* { dg-final { cleanup-tree-dump "optimized" } } */
diff --git a/gcc/testsuite/gcc.dg/binop-xor4.c b/gcc/testsuite/gcc.dg/binop-xor4.c
new file mode 100644
index 0000000..af228d96
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/binop-xor4.c
@@ -0,0 +1,14 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -fdump-tree-optimized" } */
+
+int
+foo (int a, int b, int c)
+{
+  return ((a & ~b) | (~a & b)) & c;
+}
+
+/* We expect to see "<bb N>"; confirm that, so that we know to count
+   it in the real test.  */
+/* { dg-final { scan-tree-dump-times "<bb\[^>\]*>" 1 "optimized" } } */
+/* { dg-final { scan-tree-dump-times "\^" 1 "optimized" } } */
+/* { dg-final { cleanup-tree-dump "optimized" } } */
diff --git a/gcc/testsuite/gcc.dg/binop-xor5.c b/gcc/testsuite/gcc.dg/binop-xor5.c
new file mode 100644
index 0000000..5f2b8df
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/binop-xor5.c
@@ -0,0 +1,15 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -fdump-tree-optimized" } */
+
+int
+foo (int a, int b, int c)
+{
+  return ((a & ~b & c) | (~a & b & c));
+}
+
+/* We expect to see "<bb N>"; confirm that, so that we know to count
+   it in the real test.  */
+/* { dg-final { scan-tree-dump-times "<bb\[^>\]*>" 1 "optimized" } } */
+/* { dg-final { scan-tree-dump-times "\^" 1 "optimized" } } */
+/* { dg-final { scan-tree-dump-times "\&" 1 "optimized" } } */
+/* { dg-final { cleanup-tree-dump "optimized" } } */