import newlib-2000-02-17 snapshot

1 files changed, 48 insertions, 0 deletions

diff --git a/newlib/libm/common/sf_logb.c b/newlib/libm/common/sf_logb.c
new file mode 100644
index 000000000..6e67637fe
--- /dev/null
+++ b/newlib/libm/common/sf_logb.c
@@ -0,0 +1,48 @@
+/* sf_logb.c -- float version of s_logb.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.
+ * ====================================================
+ */
+
+#include "fdlibm.h"
+
+#ifdef __STDC__
+	float logbf(float x)
+#else
+	float logbf(x)
+	float x;
+#endif
+{
+	__int32_t ix;
+	GET_FLOAT_WORD(ix,x);
+	ix &= 0x7fffffff;			/* high |x| */
+	if(ix==0) return (float)-1.0/fabsf(x);
+	if(ix>=0x7f800000) return x*x;
+	if((ix>>=23)==0) 			/* IEEE 754 logb */
+		return -126.0; 
+	else
+		return (float) (ix-127); 
+}
+
+#ifdef _DOUBLE_IS_32BITS
+
+#ifdef __STDC__
+	double logb(double x)
+#else
+	double logb(x)
+	double x;
+#endif
+{
+	return (double) logbf((float) x);
+}
+
+#endif /* defined(_DOUBLE_IS_32BITS) */