glibc/sysdeps/ieee754/dbl-64/e_log2.c
Ulrich Drepper 601d294296 Update.
2001-06-04  Bruno Haible  <haible@clisp.cons.org>

	* iconv/loop.c (UNICODE_TAG_HANDLER): New macro.
	* iconv/gconv_simple.c (__gconv_transform_internal_ascii): Invoke
	UNICODE_TAG_HANDLER.
	(__gconv_transform_internal_ucs2): Likewise.
	(__gconv_transform_internal_ucs2reverse): Likewise.
	* iconvdata/8bit-gap.c (BODY for TO_LOOP): Invoke UNICODE_TAG_HANDLER.
	* iconvdata/8bit-generic.c (BODY for TO_LOOP): Likewise.
	* iconvdata/ansi_x3.110.c (BODY for TO_LOOP): Likewise.
	* iconvdata/big5.c (BODY for TO_LOOP): Likewise.
	* iconvdata/big5hkscs.c (BODY for TO_LOOP): Likewise.
	* iconvdata/cp1255.c (BODY for TO_LOOP): Likewise.
	* iconvdata/cp1258.c (BODY for TO_LOOP): Likewise.
	* iconvdata/euc-cn.c (BODY for TO_LOOP): Likewise.
	* iconvdata/euc-jp.c (BODY for TO_LOOP): Likewise.
	* iconvdata/euc-kr.c (BODY for TO_LOOP): Likewise.
	* iconvdata/euc-tw.c (BODY for TO_LOOP): Likewise.
	* iconvdata/gbk.c (BODY for TO_LOOP): Likewise.
	* iconvdata/ibm930.c (BODY for TO_LOOP): Likewise.
	* iconvdata/ibm932.c (BODY for TO_LOOP): Likewise.
	* iconvdata/ibm933.c (BODY for TO_LOOP): Likewise.
	* iconvdata/ibm935.c (BODY for TO_LOOP): Likewise.
	* iconvdata/ibm937.c (BODY for TO_LOOP): Likewise.
	* iconvdata/ibm939.c (BODY for TO_LOOP): Likewise.
	* iconvdata/ibm943.c (BODY for TO_LOOP): Likewise.
	* iconvdata/iso646.c (BODY for TO_LOOP): Likewise.
	* iconvdata/iso8859-1.c (BODY for TO_LOOP): Likewise.
	* iconvdata/iso_6937.c (BODY for TO_LOOP): Likewise.
	* iconvdata/iso_6937-2.c (BODY for TO_LOOP): Likewise.
	* iconvdata/iso-2022-cn.c (BODY for TO_LOOP): Likewise.
	* iconvdata/iso-2022-cn-ext.c (BODY for TO_LOOP): Likewise.
	* iconvdata/iso-2022-kr.c (BODY for TO_LOOP): Likewise.
	* iconvdata/johab.c (BODY for TO_LOOP): Likewise.
	* iconvdata/sjis.c (BODY for TO_LOOP): Likewise.
	* iconvdata/t.61.c (BODY for TO_LOOP): Likewise.
	* iconvdata/uhc.c (BODY for TO_LOOP): Likewise.
	* iconvdata/unicode.c (BODY for TO_LOOP): Likewise.
	* iconvdata/iso-2022-jp.c (TAG_none, TAG_language, TAG_language_j,
	TAG_language_ja, TAG_language_k, TAG_language_ko, TAG_language_z,
	TAG_language_zh, CURRENT_TAG_MASK): New enum values.
	(EMIT_SHIFT_TO_INIT): Don't emit an escape sequence if ASCII_set
	is already selected but set2 or tag are set.
	(conversion): New enum type.
	(cvlist_t): New type.
	(CVLIST, CVLIST_FIRST, CVLIST_REST): New macros.
	(conversion_lists): New array.
	(BODY for TO_LOOP): Keep track of Unicode 3.1 language tag. If "ja",
	prefer conversion to Japanese character sets. If "zh", prefer
	conversion to GB2312. If "ko", prefer conversion to KSC5601. Small
	optimizations.
	(INIT_PARAMS): Add tag.
	(UPDATE_PARAMS): Add tag.

2001-06-04  Bruno Haible  <haible@clisp.cons.org>

	* locale/programs/locfile.c (write_locale_data): Before creat(),
	unlink the file, to avoid crashing the processes that mmap it.  Change
	a double slash to a single slash.  Free fname in case of error return.

2001-06-02  Jakub Jelinek  <jakub@redhat.com>

	* sysdeps/i386/fpu/s_frexpl.S (__frexpl): Mostly revert 2000-12-03
	changes, do the special handling for denormal numbers, not for
	normalized numbers (patch by <trevin@xmission.com>).

	* math/test-misc.c (main): Test frexpl with denormal arguments.

2001-06-04  Jakub Jelinek  <jakub@redhat.com>

	* math/libm-test.inc (llround_test): Add two new llround tests.
	* sysdeps/ieee754/ldbl-96/s_llroundl.c (__llroundl): Don't allow
	overflow when rounding away from zero.

2001-06-04  Jakub Jelinek  <jakub@redhat.com>

	* math/Makefile (libm-calls): Add e_log2, w_log2, remove s_log2.
	* math/math_private.h (__ieee754_log2, __ieee754_log2f,
	__ieee754_log2l): New prototypes.
	* sysdeps/generic/w_log2.c: New file.
	* sysdeps/generic/w_log2f.c: New file.
	* sysdeps/generic/w_log2l.c: New file.
	* sysdeps/generic/s_log2l.c: Move...
	* sysdeps/generic/e_log2l.c: ...to here. Rename to __ieee754_log2l.
	* sysdeps/ieee754/k_standard.c (__kernel_standard): Handle log2(0)
	and log2(x < 0).
	* sysdeps/i386/fpu/s_log2.S: Move...
	* sysdeps/i386/fpu/e_log2.S: ...to here. Rename to __ieee754_log2.
	* sysdeps/i386/fpu/s_log2f.S: Move...
	* sysdeps/i386/fpu/e_log2f.S: ...to here. Rename to __ieee754_log2f.
	* sysdeps/i386/fpu/s_log2l.S: Move...
	* sysdeps/i386/fpu/e_log2l.S: ...to here. Rename to __ieee754_log2l.
	* sysdeps/m68k/fpu/s_log2.S: Move...
	* sysdeps/m68k/fpu/e_log2.S: ...to here. Rename to __ieee754_log2.
	* sysdeps/m68k/fpu/s_log2f.S: Move...
	* sysdeps/m68k/fpu/e_log2f.S: ...to here. Rename to __ieee754_log2f.
	* sysdeps/m68k/fpu/s_log2l.S: Move...
	* sysdeps/m68k/fpu/e_log2l.S: ...to here. Rename to __ieee754_log2l.
	* sysdeps/ieee754/dbl-64/s_log2.c: Move...
	* sysdeps/ieee754/dbl-64/e_log2.c: ...to here. Rename to
	__ieee754_log2.
	* sysdeps/ieee754/flt-32/s_log2f.c: Move...
	* sysdeps/ieee754/flt-32/e_log2f.c: ...to here. Rename to
	__ieee754_log2f.

2001-06-04  Jakub Jelinek  <jakub@redhat.com>

	* sysdeps/generic/w_exp2.c (u_threshold): Lower threshold so that
	even arguments which result in denormalized exp2 are accepted.
	(__exp2): Arguments equal to u_threshold already result into
	underflow.
	* sysdeps/generic/w_exp2f.c (u_threshold, __exp2f): Likewise.
	* sysdeps/generic/w_exp2l.c (u_threshold, __exp2l): Likewise.
	* sysdeps/ieee754/dbl-64/e_exp2.c (__ieee754_exp2): Lomark was too
	low, with corrected lowmark use greaterequal, not greater.
	* sysdeps/ieee754/flt-32/e_exp2f.c (__ieee754_exp2f): Likewise.

2001-06-04  Jakub Jelinek  <jakub@redhat.com>

	* math/libm-test.inc (ilogb_test): Test that ilogb(+-Inf) == INT_MAX.
	* sysdeps/i386/fpu/s_ilogb.S (__ilogb): Return INT_MAX for +-Inf.
	* sysdeps/i386/fpu/s_ilogbf.S (__ilogbf): Likewise.
	* sysdeps/i386/fpu/s_ilogbl.S (__ilogbl): Likewise.
	* sysdeps/ieee754/dbl-64/s_ilogb.c (__ilogb): Likewise.
	* sysdeps/ieee754/flt-32/s_ilogbf.c (__ilogbf): Likewise.
	* sysdeps/ieee754/ldbl-128/s_ilogbl.c (__ilogbl): Likewise.
	* sysdeps/ieee754/ldbl-96/s_ilogbl.c (__ilogbl): Likewise.

2001-06-04  Jakub Jelinek  <jakub@redhat.com>

	* sysdeps/generic/w_coshl.c (__coshl): Test if finite argument
	gave non-finite result instead of using constant in generic
	version.
	* sysdeps/generic/w_coshf.c (__coshf): Likewise.
	* sysdeps/generic/w_cosh.c (__cosh): Likewise.
	* sysdeps/generic/w_exp10.c (o_threshold, u_threshold): Remove.
	(__exp10): Test if finite argument gave non-finite result.
	* sysdeps/generic/w_exp10f.c (o_threshold, u_threshold, __exp10f):
	Likewise.
	* sysdeps/generic/w_exp10l.c (o_threshold, u_threshold, __exp10l):
	Likewise.
2001-06-04  Jakub Jelinek  <jakub@redhat.com>

	* sysdeps/ieee754/ldbl-96/e_coshl.c (__ieee754_coshl): Fix
	overflow threshold constant (log(LDBL_MAX)+M_LN2l).

2001-05-29  Bruno Haible  <haible@clisp.cons.org>

	* locale/programs/ld-ctype.c (idx_table): New struct type.
	(idx_table_init, idx_table_get, idx_table_add): New functions.
	(MAX_CHARNAMES_IDX): Remove macro.
	(locale_ctype_t): Change type of charnames_idx field.
	(ctype_startup): Change initialization of charnames_idx field.
	(find_idx): Use idx_table_get and idx_table_add for speed.

	* locale/programs/charmap.c (charmap_new_char): Fix ucs4 value
	computation of characters in a range.

2001-05-29  Bruno Haible  <haible@clisp.cons.org>

	* iconvdata/gb18030.c (__fourbyte_to_ucs1): Add mappings for <U03F4>,
	<U03F5>.
	(__ucs_to_gb18030_tab1): Likewise.
	(BODY for FROM_LOOP): Add mapping for <U00010000>..<U0010FFFF>.
	(BODY for TO_LOOP): Likewise.
	* iconvdata/tst-table-charmap.sh: Update for charmaps containing
	<U00xxxxxx> syntax.
	* iconvdata/tst-table-from.c (bmp_only): New variable.
	(utf8_decode): If bmp_only, don't return characters outside Unicode
	plane 0.
	(main): When testing UTF-8 or GB18030, set bmp_only to 1. Don't print
	a conversion line if utf8_decode returns NULL.
	* iconvdata/tst-table-to.c (main): When testing encodings other than
	UTF-8 and GB18030, loop upto U+30000 instead of U+10000. Use UTF-8
	instead of UCS-2 as input.
	* iconvdata/tst-table.sh: For GB18030, use only the part < 0x10000
	of the charmap.

2001-05-29  Bruno Haible  <haible@clisp.cons.org>

	* iconvdata/cns11643l1.c: Update to Unicode 3.1.
	(__cns11643l1_to_ucs4_tab): Regenerated.
	(__cns11643l1_from_ucs4_tab12): Regenerated.
	* iconvdata/cns11643.c: Update to Unicode 3.1.
	(__cns11643l14_to_ucs4_tab): Remove array.
	(__cns11643l3_to_ucs4_tab, __cns11643l4_to_ucs4_tab,
	__cns11643l5_to_ucs4_tab, __cns11643l6_to_ucs4_tab,
	__cns11643l7_to_ucs4_tab, __cns11643l15_to_ucs4_tab): New arrays.
	(__cns11643_from_ucs4p0_tab): Renamed from __cns11643_from_ucs4_tab.
	(__cns11643_from_ucs4p2_tab): New array.
	* iconvdata/cns11643.h (__cns11643l14_to_ucs4_tab): Remove declaration.
	(__cns11643l3_to_ucs4_tab, __cns11643l4_to_ucs4_tab,
	__cns11643l5_to_ucs4_tab, __cns11643l6_to_ucs4_tab,
	__cns11643l7_to_ucs4_tab, __cns11643l15_to_ucs4_tab): New declarations.
	(cns11643_to_ucs4): Treat planes 3, 4, 5, 6, 7, 15 instead of 14.
	(__cns11643_from_ucs4_tab): Remove declaration.
	(__cns11643_from_ucs4p0_tab, __cns11643_from_ucs4p2_tab): New
	declarations.
	(ucs4_to_cns11643): Update for new arrays. Treat U+3400..U+4DFF and
	U+20000..U+2A6D6.
	* iconvdata/cns11643l2.h (__cns11643_from_ucs4_tab): Remove
	declaration.
	(__cns11643_from_ucs4p0_tab): New declaration.
	(ucs4_to_cns11643l2): Update for new arrays.
	* iconvdata/iso-2022-cn-ext.c (BODY for FROM_LOOP): Handle planes
	3 to 7.
	(BODY for TO_LOOP): Handle planes 3 to 7, instead of plane 14.
	* iconvdata/EUC-TW.irreversible: New file.
	* iconvdata/tst-table.sh: Use it.
	* iconvdata/Makefile (distribute): Add CP1255.irreversible,
	CP1258.irreversible, EUC-TW.irreversible.

2001-05-29  Bruno Haible  <haible@clisp.cons.org>

	* locale/C-translit.h.in: Add transliterations for new Unicode 3.1
	mathematical symbols.
2001-06-06 12:55:46 +00:00

131 lines
3.8 KiB
C

/* Adapted for log2 by Ulrich Drepper <drepper@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.
* ====================================================
*/
/* __ieee754_log2(x)
* Return the logarithm to base 2 of x
*
* Method :
* 1. Argument Reduction: find k and f such that
* x = 2^k * (1+f),
* where sqrt(2)/2 < 1+f < sqrt(2) .
*
* 2. Approximation of log(1+f).
* Let s = f/(2+f) ; based on log(1+f) = log(1+s) - log(1-s)
* = 2s + 2/3 s**3 + 2/5 s**5 + .....,
* = 2s + s*R
* We use a special Reme algorithm on [0,0.1716] to generate
* a polynomial of degree 14 to approximate R The maximum error
* of this polynomial approximation is bounded by 2**-58.45. In
* other words,
* 2 4 6 8 10 12 14
* R(z) ~ Lg1*s +Lg2*s +Lg3*s +Lg4*s +Lg5*s +Lg6*s +Lg7*s
* (the values of Lg1 to Lg7 are listed in the program)
* and
* | 2 14 | -58.45
* | Lg1*s +...+Lg7*s - R(z) | <= 2
* | |
* Note that 2s = f - s*f = f - hfsq + s*hfsq, where hfsq = f*f/2.
* In order to guarantee error in log below 1ulp, we compute log
* by
* log(1+f) = f - s*(f - R) (if f is not too large)
* log(1+f) = f - (hfsq - s*(hfsq+R)). (better accuracy)
*
* 3. Finally, log(x) = k + log(1+f).
* = k+(f-(hfsq-(s*(hfsq+R))))
*
* Special cases:
* log2(x) is NaN with signal if x < 0 (including -INF) ;
* log2(+INF) is +INF; log(0) is -INF with signal;
* log2(NaN) is that NaN with no signal.
*
* Constants:
* The hexadecimal values are the intended ones for the following
* constants. The decimal values may be used, provided that the
* compiler will convert from decimal to binary accurately enough
* to produce the hexadecimal values shown.
*/
#include "math.h"
#include "math_private.h"
#ifdef __STDC__
static const double
#else
static double
#endif
ln2 = 0.69314718055994530942,
two54 = 1.80143985094819840000e+16, /* 43500000 00000000 */
Lg1 = 6.666666666666735130e-01, /* 3FE55555 55555593 */
Lg2 = 3.999999999940941908e-01, /* 3FD99999 9997FA04 */
Lg3 = 2.857142874366239149e-01, /* 3FD24924 94229359 */
Lg4 = 2.222219843214978396e-01, /* 3FCC71C5 1D8E78AF */
Lg5 = 1.818357216161805012e-01, /* 3FC74664 96CB03DE */
Lg6 = 1.531383769920937332e-01, /* 3FC39A09 D078C69F */
Lg7 = 1.479819860511658591e-01; /* 3FC2F112 DF3E5244 */
#ifdef __STDC__
static const double zero = 0.0;
#else
static double zero = 0.0;
#endif
#ifdef __STDC__
double __ieee754_log2(double x)
#else
double __ieee754_log2(x)
double x;
#endif
{
double hfsq,f,s,z,R,w,t1,t2,dk;
int32_t k,hx,i,j;
u_int32_t lx;
EXTRACT_WORDS(hx,lx,x);
k=0;
if (hx < 0x00100000) { /* x < 2**-1022 */
if (((hx&0x7fffffff)|lx)==0)
return -two54/(x-x); /* log(+-0)=-inf */
if (hx<0) return (x-x)/(x-x); /* 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);
dk = (double) k;
f = x-1.0;
if((0x000fffff&(2+hx))<3) { /* |f| < 2**-20 */
if(f==zero) return dk;
R = f*f*(0.5-0.33333333333333333*f);
return dk-(R-f)/ln2;
}
s = f/(2.0+f);
z = s*s;
i = hx-0x6147a;
w = z*z;
j = 0x6b851-hx;
t1= w*(Lg2+w*(Lg4+w*Lg6));
t2= z*(Lg1+w*(Lg3+w*(Lg5+w*Lg7)));
i |= j;
R = t2+t1;
if(i>0) {
hfsq=0.5*f*f;
return dk-((hfsq-(s*(hfsq+R)))-f)/ln2;
} else {
return dk-((s*(f-R))-f)/ln2;
}
}