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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/flt-32/s_ilogbf.c
parent86421aa57ecfd70963ae66848bd6a6dd3b8e0fe6 (diff)
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Update.
Diffstat (limited to 'sysdeps/ieee754/flt-32/s_ilogbf.c')
-rw-r--r--sysdeps/ieee754/flt-32/s_ilogbf.c44
1 files changed, 44 insertions, 0 deletions
diff --git a/sysdeps/ieee754/flt-32/s_ilogbf.c b/sysdeps/ieee754/flt-32/s_ilogbf.c
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+++ b/sysdeps/ieee754/flt-32/s_ilogbf.c
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+/* s_ilogbf.c -- float version of s_ilogb.c.
+ * Conversion to float by Ian Lance Taylor, Cygnus Support, ian@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: s_ilogbf.c,v 1.4 1995/05/10 20:47:31 jtc Exp $";
+#endif
+
+#include "math.h"
+#include "math_private.h"
+
+#ifdef __STDC__
+	int __ilogbf(float x)
+#else
+	int __ilogbf(x)
+	float x;
+#endif
+{
+	int32_t hx,ix;
+
+	GET_FLOAT_WORD(hx,x);
+	hx &= 0x7fffffff;
+	if(hx<0x00800000) {
+	    if(hx==0)
+		return FP_ILOGB0;	/* ilogb(0) = FP_ILOGB0 */
+	    else			/* subnormal x */
+	        for (ix = -126,hx<<=8; hx>0; hx<<=1) ix -=1;
+	    return ix;
+	}
+	else if (hx<0x7f800000) return (hx>>23)-127;
+	else return FP_ILOGBNAN;
+}
+weak_alias (__ilogbf, ilogbf)