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authorUlrich Drepper <drepper@redhat.com>1999-07-14 00:54:57 +0000
committerUlrich Drepper <drepper@redhat.com>1999-07-14 00:54:57 +0000
commitabfbdde177c3a7155070dda1b2cdc8292054cc26 (patch)
treee021306b596381fbf8311d2b7eb294e918ff17c8 /sysdeps/ieee754/dbl-64/s_isinf.c
parent86421aa57ecfd70963ae66848bd6a6dd3b8e0fe6 (diff)
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Update.
Diffstat (limited to 'sysdeps/ieee754/dbl-64/s_isinf.c')
-rw-r--r--sysdeps/ieee754/dbl-64/s_isinf.c32
1 files changed, 32 insertions, 0 deletions
diff --git a/sysdeps/ieee754/dbl-64/s_isinf.c b/sysdeps/ieee754/dbl-64/s_isinf.c
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+++ b/sysdeps/ieee754/dbl-64/s_isinf.c
@@ -0,0 +1,32 @@
+/*
+ * Written by J.T. Conklin <jtc@netbsd.org>.
+ * Changed to return -1 for -Inf by Ulrich Drepper <drepper@cygnus.com>.
+ * Public domain.
+ */
+
+#if defined(LIBM_SCCS) && !defined(lint)
+static char rcsid[] = "$NetBSD: s_isinf.c,v 1.3 1995/05/11 23:20:14 jtc Exp $";
+#endif
+
+/*
+ * isinf(x) returns 1 is x is inf, -1 if x is -inf, else 0;
+ * no branching!
+ */
+
+#include "math.h"
+#include "math_private.h"
+
+int
+__isinf (double x)
+{
+	int32_t hx,lx;
+	EXTRACT_WORDS(hx,lx,x);
+	lx |= (hx & 0x7fffffff) ^ 0x7ff00000;
+	lx |= -lx;
+	return ~(lx >> 31) & (hx >> 30);
+}
+weak_alias (__isinf, isinf)
+#ifdef NO_LONG_DOUBLE
+strong_alias (__isinf, __isinfl)
+weak_alias (__isinf, isinfl)
+#endif