PR middle-end/52209

	* expr.c (expand_expr_real_2) <case BIT_NOT_EXPR>: Only expand using
	XOR for reduce_bit_field if type is unsigned.

	* gcc.c-torture/execute/pr52209.c: New test.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@184151 138bc75d-0d04-0410-961f-82ee72b054a4

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 1a97108..549af73 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2012-02-13  Jakub Jelinek  <jakub@redhat.com>
+
+       PR middle-end/52209
+       * expr.c (expand_expr_real_2) <case BIT_NOT_EXPR>: Only expand using
+       XOR for reduce_bit_field if type is unsigned.
+
 2012-02-12  Eric Botcazou  <ebotcazou@adacore.com>
 
        * config/sparc/sparc.h (CANNOT_CHANGE_MODE_CLASS): In 64-bit mode,

diff --git a/gcc/expr.c b/gcc/expr.c
index e63ed3b..2e716cc 100644 (file)
--- a/gcc/expr.c
+++ b/gcc/expr.c
@@ -8600,8 +8600,9 @@ expand_expr_real_2 (sepops ops, rtx target, enum machine_mode tmode,
       if (modifier == EXPAND_STACK_PARM)
        target = 0;
       /* In case we have to reduce the result to bitfield precision
-        expand this as XOR with a proper constant instead.  */
-      if (reduce_bit_field)
+        for unsigned bitfield expand this as XOR with a proper constant
+        instead.  */
+      if (reduce_bit_field && TYPE_UNSIGNED (type))
        temp = expand_binop (mode, xor_optab, op0,
                             immed_double_int_const
                               (double_int_mask (TYPE_PRECISION (type)), mode),

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 66abdd0..e75cc5e 100644 (file)
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2012-02-13  Jakub Jelinek  <jakub@redhat.com>
+
+       PR middle-end/52209
+       * gcc.c-torture/execute/pr52209.c: New test.
+
 2012-02-12  Mikael Morin  <mikael@gcc.gnu.org>
 
        PR fortran/50981

diff --git a/gcc/testsuite/gcc.c-torture/execute/pr52209.c b/gcc/testsuite/gcc.c-torture/execute/pr52209.c
new file mode 100644 (file)
index 0000000..f1d5b1f
--- /dev/null
+++ b/gcc/testsuite/gcc.c-torture/execute/pr52209.c
@@ -0,0 +1,14 @@
+/* PR middle-end/52209 */
+
+extern void abort (void);
+struct S0 { int f2 : 1; } c;
+int b;
+
+int
+main ()
+{
+  b = -1 ^ c.f2;
+  if (b != -1)
+    abort ();
+  return 0;
+}