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-rw-r--r--sysdeps/x86/fpu/s_isnanl.c45
1 files changed, 45 insertions, 0 deletions
diff --git a/sysdeps/x86/fpu/s_isnanl.c b/sysdeps/x86/fpu/s_isnanl.c
new file mode 100644
index 0000000000..45541df08a
--- /dev/null
+++ b/sysdeps/x86/fpu/s_isnanl.c
@@ -0,0 +1,45 @@
+/* s_isnanl.c -- long double version for i387 of s_isnan.c.
+ * Conversion to long double by Ulrich Drepper,
+ * Cygnus Support, drepper@cygnus.com.
+ */
+
+/*
+ * ====================================================
+ * 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: $";
+#endif
+
+/*
+ * isnanl(x) returns 1 is x is nan, else 0;
+ * no branching!
+ */
+
+#include <math.h>
+#include <math_private.h>
+
+int __isnanl(long double x)
+{
+	int32_t se,hx,lx,pn;
+	GET_LDOUBLE_WORDS(se,hx,lx,x);
+	se = (se & 0x7fff) << 1;
+	/* Detect pseudo-normal numbers, i.e. exponent is non-zero and the top
+	   bit of the significand is not set.   */
+	pn = (uint32_t)((~hx & 0x80000000) & (se|(-se)))>>31;
+	/* Clear the significand bit when computing mantissa.  */
+	lx |= hx & 0x7fffffff;
+	se |= (uint32_t)(lx|(-lx))>>31;
+	se = 0xfffe - se;
+
+	return (int)(((uint32_t)(se)) >> 16) | pn;
+}
+hidden_def (__isnanl)
+weak_alias (__isnanl, isnanl)