From 82b52495adf6738472755dbfcbe69c392a3edde2 Mon Sep 17 00:00:00 2001 From: das Date: Sun, 5 Dec 2010 22:11:22 +0000 Subject: Add log2() and log2f(). --- lib/msun/Makefile | 5 ++-- lib/msun/Symbol.map | 2 ++ lib/msun/man/log.3 | 18 ++++++++++++-- lib/msun/man/math.3 | 18 ++++++++------ lib/msun/src/e_log2.c | 60 +++++++++++++++++++++++++++++++++++++++++++++ lib/msun/src/e_log2f.c | 54 ++++++++++++++++++++++++++++++++++++++++ lib/msun/src/math.h | 2 ++ lib/msun/src/math_private.h | 2 ++ 8 files changed, 149 insertions(+), 12 deletions(-) create mode 100644 lib/msun/src/e_log2.c create mode 100644 lib/msun/src/e_log2f.c diff --git a/lib/msun/Makefile b/lib/msun/Makefile index 929af97..0048e25 100644 --- a/lib/msun/Makefile +++ b/lib/msun/Makefile @@ -45,7 +45,8 @@ COMMON_SRCS= b_exp.c b_log.c b_tgamma.c \ e_expf.c e_fmod.c e_fmodf.c e_gamma.c e_gamma_r.c e_gammaf.c \ e_gammaf_r.c e_hypot.c e_hypotf.c e_j0.c e_j0f.c e_j1.c e_j1f.c \ e_jn.c e_jnf.c e_lgamma.c e_lgamma_r.c e_lgammaf.c e_lgammaf_r.c \ - e_log.c e_log10.c e_log10f.c e_logf.c e_pow.c e_powf.c e_rem_pio2.c \ + e_log.c e_log10.c e_log10f.c e_log2.c e_log2f.c e_logf.c \ + e_pow.c e_powf.c e_rem_pio2.c \ e_rem_pio2f.c e_remainder.c e_remainderf.c e_scalb.c e_scalbf.c \ e_sinh.c e_sinhf.c e_sqrt.c e_sqrtf.c fenv.c \ k_cos.c k_cosf.c k_rem_pio2.c k_sin.c k_sinf.c \ @@ -175,7 +176,7 @@ MLINKS+=j0.3 j1.3 j0.3 jn.3 j0.3 y0.3 j0.3 y1.3 j0.3 y1f.3 j0.3 yn.3 MLINKS+=j0.3 j0f.3 j0.3 j1f.3 j0.3 jnf.3 j0.3 y0f.3 j0.3 ynf.3 MLINKS+=lgamma.3 gamma.3 lgamma.3 gammaf.3 lgamma.3 lgammaf.3 \ lgamma.3 tgamma.3 lgamma.3 tgammaf.3 -MLINKS+=log.3 log10.3 log.3 log10f.3 log.3 log1p.3 log.3 log1pf.3 log.3 logf.3 +MLINKS+=log.3 log10.3 log.3 log10f.3 log.3 log1p.3 log.3 log1pf.3 log.3 logf.3 log.3 log2.3 log.3 log2f.3 MLINKS+=lrint.3 llrint.3 lrint.3 llrintf.3 lrint.3 llrintl.3 \ lrint.3 lrintf.3 lrint.3 lrintl.3 MLINKS+=lround.3 llround.3 lround.3 llroundf.3 lround.3 llroundl.3 \ diff --git a/lib/msun/Symbol.map b/lib/msun/Symbol.map index 429a76f..69618e6 100644 --- a/lib/msun/Symbol.map +++ b/lib/msun/Symbol.map @@ -222,4 +222,6 @@ FBSD_1.1 { /* First added in 9.0-CURRENT */ FBSD_1.2 { __isnanf; + log2; + log2f; }; diff --git a/lib/msun/man/log.3 b/lib/msun/man/log.3 index 1934473..b9fd83c 100644 --- a/lib/msun/man/log.3 +++ b/lib/msun/man/log.3 @@ -1,4 +1,4 @@ -.\" Copyright (c) 2008 David Schultz +.\" Copyright (c) 2008-2010 David Schultz .\" All rights reserved. .\" .\" Redistribution and use in source and binary forms, with or without @@ -24,7 +24,7 @@ .\" .\" $FreeBSD$ .\" -.Dd January 17, 2008 +.Dd December 5, 2010 .Dt LOG 3 .Os .Sh NAME @@ -33,6 +33,8 @@ .Nm logl , .Nm log10 , .Nm log10f , +.Nm log2 , +.Nm log2f , .Nm log1p , .Nm log1pf .Nd logarithm functions @@ -49,6 +51,10 @@ .Ft float .Fn log10f "float x" .Ft double +.Fn log2 "double x" +.Ft float +.Fn log2f "float x" +.Ft double .Fn log1p "double x" .Ft float .Fn log1pf "float x" @@ -65,6 +71,12 @@ The and .Fn log10f functions compute the logarithm base 10 of +.Fa x , +while +.Fn log2 +and +.Fn log2f +compute the logarithm base 2 of .Fa x . .Pp The @@ -97,6 +109,8 @@ The .Fn logf , .Fn log10 , .Fn log10f , +.Fn log2 , +.Fn log2f , .Fn log1p , and .Fn log1pf diff --git a/lib/msun/man/math.3 b/lib/msun/man/math.3 index 4690a9a..8e79ce5 100644 --- a/lib/msun/man/math.3 +++ b/lib/msun/man/math.3 @@ -28,7 +28,7 @@ .\" from: @(#)math.3 6.10 (Berkeley) 5/6/91 .\" $FreeBSD$ .\" -.Dd December 16, 2007 +.Dd December 5, 2010 .Dt MATH 3 .Os .Sh NAME @@ -182,7 +182,7 @@ lgamma log gamma function log natural logarithm log10 logarithm to base 10 log1p log(1+x) -.\" log2 base 2 logarithm +log2 base 2 logarithm pow exponential x**y sin trigonometric function sinh hyperbolic function @@ -194,7 +194,7 @@ y1 Bessel function of the second kind of the order 1 yn Bessel function of the second kind of the order n .El .Pp -Unlike the algebraic functions listed earlier, the routines +The routines in this section may not produce a result that is correctly rounded, so reproducible results cannot be guaranteed across platforms. For most of these functions, however, incorrect rounding occurs @@ -221,18 +221,20 @@ and values, were written for or imported into subsequent versions of FreeBSD. .Sh BUGS The -.Fn log2 -function is missing, and many functions are not available in their +.Fn cbrt +function and many of the transcendental functions +are not available in their .Vt "long double" variants. .Pp Many of the routines to compute transcendental functions produce inaccurate results in other than the default rounding mode. .Pp -On some architectures, trigonometric argument reduction is not -performed accurately, resulting in errors greater than 1 +On the i386 platform, trigonometric argument reduction is not +performed accurately for very large arguments, resulting in errors +greater than 1 .Em ulp -for large arguments to +for such arguments to .Fn cos , .Fn sin , and diff --git a/lib/msun/src/e_log2.c b/lib/msun/src/e_log2.c new file mode 100644 index 0000000..8a729d5 --- /dev/null +++ b/lib/msun/src/e_log2.c @@ -0,0 +1,60 @@ + +/* @(#)e_log10.c 1.3 95/01/18 */ +/* + * ==================================================== + * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. + * + * Developed at SunSoft, a Sun Microsystems, Inc. business. + * Permission to use, copy, modify, and distribute this + * software is freely granted, provided that this notice + * is preserved. + * ==================================================== + */ + +#include +__FBSDID("$FreeBSD$"); + +/* log2(x) + * Return the base 2 logarithm of x. + */ + +#include "math.h" +#include "math_private.h" +#include "k_log.h" + +static const double +two54 = 1.80143985094819840000e+16, /* 0x43500000, 0x00000000 */ +ivln2hi = 0x1.71547652000p+0, +ivln2lo = 0x1.705fc2eefa2p-33; + +static const double zero = 0.0; + +double +__ieee754_log2(double x) +{ + double f,hi,lo; + int32_t i,k,hx; + u_int32_t lx; + + EXTRACT_WORDS(hx,lx,x); + + k=0; + if (hx < 0x00100000) { /* x < 2**-1022 */ + if (((hx&0x7fffffff)|lx)==0) + return -two54/zero; /* log(+-0)=-inf */ + if (hx<0) return (x-x)/zero; /* log(-#) = NaN */ + k -= 54; x *= two54; /* subnormal number, scale up x */ + GET_HIGH_WORD(hx,x); + } + if (hx >= 0x7ff00000) return x+x; + k += (hx>>20)-1023; + hx &= 0x000fffff; + i = (hx+0x95f64)&0x100000; + SET_HIGH_WORD(x,hx|(i^0x3ff00000)); /* normalize x or x/2 */ + k += (i>>20); + f = __kernel_log(x); + hi = x = x - 1; + SET_LOW_WORD(hi,0); + lo = x - hi; + return (x+f)*ivln2lo + (lo+f)*ivln2hi + hi*ivln2hi + k; +} diff --git a/lib/msun/src/e_log2f.c b/lib/msun/src/e_log2f.c new file mode 100644 index 0000000..6b2b966 --- /dev/null +++ b/lib/msun/src/e_log2f.c @@ -0,0 +1,54 @@ +/* + * ==================================================== + * 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 +__FBSDID("$FreeBSD$"); + +#include "math.h" +#include "math_private.h" +#include "k_logf.h" + +static const float +two25 = 3.3554432000e+07, /* 0x4c000000 */ +ivln2hi = 0x1.716p+0f, +ivln2lo = -0x1.7135a8fa03d11p-13; + +static const float zero = 0.0; + +float +__ieee754_log2f(float x) +{ + float f,hi,lo; + int32_t i,k,hx; + + GET_FLOAT_WORD(hx,x); + + k=0; + if (hx < 0x00800000) { /* x < 2**-126 */ + if ((hx&0x7fffffff)==0) + return -two25/zero; /* log(+-0)=-inf */ + if (hx<0) return (x-x)/zero; /* log(-#) = NaN */ + k -= 25; x *= two25; /* subnormal number, scale up x */ + GET_FLOAT_WORD(hx,x); + } + if (hx >= 0x7f800000) return x+x; + k += (hx>>23)-127; + hx &= 0x007fffff; + i = (hx+(0x4afb0d))&0x800000; + SET_FLOAT_WORD(x,hx|(i^0x3f800000)); /* normalize x or x/2 */ + k += (i>>23); + f = __kernel_logf(x); + x = x - 1; + GET_FLOAT_WORD(hx,x); + SET_FLOAT_WORD(hi,hx&0xfffff000); + lo = x - hi; + return (x+f)*ivln2lo + (lo+f)*ivln2hi + hi*ivln2hi + k; +} diff --git a/lib/msun/src/math.h b/lib/msun/src/math.h index 9109727..9aa2484 100644 --- a/lib/msun/src/math.h +++ b/lib/msun/src/math.h @@ -236,6 +236,7 @@ double lgamma(double); long long llrint(double); long long llround(double); double log1p(double); +double log2(double); double logb(double); long lrint(double); long lround(double); @@ -319,6 +320,7 @@ int ilogbf(float) __pure2; float ldexpf(float, int); float log10f(float); float log1pf(float); +float log2f(float); float logf(float); float modff(float, float *); /* fundamentally !__pure2 */ diff --git a/lib/msun/src/math_private.h b/lib/msun/src/math_private.h index 10c92f4..d79f808 100644 --- a/lib/msun/src/math_private.h +++ b/lib/msun/src/math_private.h @@ -292,6 +292,7 @@ irint(double x) #define __ieee754_acos acos #define __ieee754_acosh acosh #define __ieee754_log log +#define __ieee754_log2 log2 #define __ieee754_atanh atanh #define __ieee754_asin asin #define __ieee754_atan2 atan2 @@ -330,6 +331,7 @@ irint(double x) #define __ieee754_lgammaf_r lgammaf_r #define __ieee754_gammaf_r gammaf_r #define __ieee754_log10f log10f +#define __ieee754_log2f log2f #define __ieee754_sinhf sinhf #define __ieee754_hypotf hypotf #define __ieee754_j0f j0f -- cgit v1.1