src/libm/s_copysign.c
changeset 2756 a98604b691c8
child 3162 dc1eb82ffdaa
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/libm/s_copysign.c	Mon Sep 15 06:33:23 2008 +0000
@@ -0,0 +1,42 @@
+/* @(#)s_copysign.c 5.1 93/09/24 */
+/*
+ * ====================================================
+ * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
+ *
+ * Developed at SunPro, a Sun Microsystems, Inc. business.
+ * Permission to use, copy, modify, and distribute this
+ * software is freely granted, provided that this notice
+ * is preserved.
+ * ====================================================
+ */
+
+#if defined(LIBM_SCCS) && !defined(lint)
+static char rcsid[] =
+    "$NetBSD: s_copysign.c,v 1.8 1995/05/10 20:46:57 jtc Exp $";
+#endif
+
+/*
+ * copysign(double x, double y)
+ * copysign(x,y) returns a value with the magnitude of x and
+ * with the sign bit of y.
+ */
+
+#include "math.h"
+#include "math_private.h"
+
+libm_hidden_proto(copysign)
+#ifdef __STDC__
+     double copysign(double x, double y)
+#else
+     double copysign(x, y)
+     double x, y;
+#endif
+{
+    u_int32_t hx, hy;
+    GET_HIGH_WORD(hx, x);
+    GET_HIGH_WORD(hy, y);
+    SET_HIGH_WORD(x, (hx & 0x7fffffff) | (hy & 0x80000000));
+    return x;
+}
+
+libm_hidden_def(copysign)