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Diffstat (limited to 'sysdeps/ieee754/ldbl-128ibm/s_logbl.c')
-rw-r--r--sysdeps/ieee754/ldbl-128ibm/s_logbl.c47
1 files changed, 47 insertions, 0 deletions
diff --git a/sysdeps/ieee754/ldbl-128ibm/s_logbl.c b/sysdeps/ieee754/ldbl-128ibm/s_logbl.c
new file mode 100644
index 0000000..0c61cda
--- /dev/null
+++ b/sysdeps/ieee754/ldbl-128ibm/s_logbl.c
@@ -0,0 +1,47 @@
+/* s_logbl.c -- long double version of s_logb.c.
+ * Conversion to IEEE quad long double by Jakub Jelinek, jj@ultra.linux.cz.
+ */
+
+/*
+ * ====================================================
+ * 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
+
+/*
+ * long double logbl(x)
+ * IEEE 754 logb. Included to pass IEEE test suite. Not recommend.
+ * Use ilogb instead.
+ */
+
+#include "math.h"
+#include "math_private.h"
+#include <math_ldbl_opt.h>
+
+#ifdef __STDC__
+ long double __logbl(long double x)
+#else
+ long double __logbl(x)
+ long double x;
+#endif
+{
+ int64_t lx,hx;
+ GET_LDOUBLE_WORDS64(hx,lx,x);
+ hx &= 0x7fffffffffffffffLL; /* high |x| */
+ if((hx|(lx&0x7fffffffffffffffLL))==0) return -1.0/fabs(x);
+ if(hx>=0x7ff0000000000000LL) return x*x;
+ if((hx>>=52)==0) /* IEEE 754 logb */
+ return -1022.0;
+ else
+ return (long double) (hx-0x3ff);
+}
+long_double_symbol (libm, __logbl, logbl);