- 80-bit and quad precision trigonometric and other most

important functions: acosl, asinl, atanl, atan2l, cosl,
sinl, tanl, exp2l, frexpl, ilogbl, ldexpl, logbl, scalbnl,
fabsl, hypotl, powl, sqrtl, rintl, copysignl, nanl, fdiml,
fmaxl, fminl.  mostly taken from freebsd, needed alot of
changes to adapt.  note, these are all c versions;  and are
quite slow when architectures have, e.g. sqrt.  assembly
versions will be added afterwards
- make them .weak/__weak_alias to the double precision
versions on other archs
- no need to have two finites.  finite() and finitef() are
non-standard 3BSD obsolete versions of isfinite.  remove
from libm.  make them weak_alias in libc to __isfinite and
__isfinitef instead.  similarly make 3BSD obsolete versions
of isinf, isinff, isnan, isnanf weak_aliases to C99's
__isinf, __isinff, __isnan, __isnanf
- remove unused infinity.c.  the c library has infinities
for each supported platform
- use STRICT_ASSIGN cast hack for _kernel_rem_pio2, so that
the double version has a chance of working on i386 with
extra precision
- avoid storing multiple copies of the pi/2 array, since
it won't vary
- bump major due to removed finite/finitef.  although they
will be in libc, which anything is linked to, minor bump
might be enough
ok millert@.   tested by sthen@, jsg@, ajacoutot@, kili@, naddy@

1 files changed, 77 insertions, 0 deletions

diff --git a/lib/libm/src/s_logbl.c b/lib/libm/src/s_logbl.c
new file mode 100644
index 00000000000..7de6ede4fd0
--- /dev/null
+++ b/lib/libm/src/s_logbl.c
@@ -0,0 +1,77 @@
+/*	$OpenBSD: s_logbl.c,v 1.1 2008/12/09 20:00:35 martynas Exp $	*/
+/*
+ * From: @(#)s_ilogb.c 5.1 93/09/24
+ * ====================================================
+ * 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 <sys/types.h>
+#include <machine/ieee.h>
+#include <float.h>
+#include <limits.h>
+#include <math.h>
+
+long double
+logbl(long double x)
+{
+	union {
+		long double e;
+		struct ieee_ext bits;
+	} u;
+	unsigned long m;
+	int b;
+
+	u.e = x;
+	if (u.bits.ext_exp == 0) {
+		if ((u.bits.ext_fracl
+#ifdef EXT_FRACLMBITS
+			| u.bits.ext_fraclm
+#endif /* EXT_FRACLMBITS */
+#ifdef EXT_FRACHMBITS
+			| u.bits.ext_frachm
+#endif /* EXT_FRACHMBITS */
+			| u.bits.ext_frach) == 0) {	/* x == 0 */
+			u.bits.ext_sign = 1;
+			return (1.0L / u.e);
+		}
+		/* denormalized */
+		if (u.bits.ext_frach == 0
+#ifdef EXT_FRACHMBITS
+			&& u.bits.ext_frachm == 0
+#endif
+			) {
+			m = 1lu << (EXT_FRACLBITS - 1);
+			for (b = EXT_FRACHBITS; !(u.bits.ext_fracl & m); m >>= 1)
+				b++;
+#if defined(EXT_FRACHMBITS) && defined(EXT_FRACLMBITS)
+			m = 1lu << (EXT_FRACLMBITS - 1);
+			for (b += EXT_FRACHMBITS; !(u.bits.ext_fraclm & m);
+				m >>= 1)
+				b++;
+#endif /* defined(EXT_FRACHMBITS) && defined(EXT_FRACLMBITS) */
+		} else {
+			m = 1lu << (EXT_FRACHBITS - 1);
+			for (b = 0; !(u.bits.ext_frach & m); m >>= 1)
+				b++;
+#ifdef EXT_FRACHMBITS
+			m = 1lu << (EXT_FRACHMBITS - 1);
+			for (; !(u.bits.ext_frachm & m); m >>= 1)
+				b++;
+#endif /* EXT_FRACHMBITS */
+		}
+#ifdef EXT_IMPLICIT_NBIT
+		b++;
+#endif
+		return ((long double)(LDBL_MIN_EXP - b - 1));
+	}
+	if (u.bits.ext_exp < (LDBL_MAX_EXP << 1) - 1)	/* normal */
+		return ((long double)(u.bits.ext_exp - LDBL_MAX_EXP + 1));
+	else						/* +/- inf or nan */
+		return (x * x);
+}