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https://git.code.sf.net/p/mingw-w64/mingw-w64
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b190082731
As of Jan. 06 2023. Changelog from http://netlib.org/fp/changes (filtered): 20121220 dtoa.c and gdtoa.tgz: to avoid a possible one-time race when Infinity or NaN appear in decimal->binary conversions done in parallel threads, replace hexdig_init() with static initialization. 20131209 dtoa.c, gdtoa.tgz: when strtod computes its starting approximation, allow z to involve one more digit for IEEE arithmetic and two more digits for IBM-mainframe and VAX arithmetics. Thanks to Walter Qian (water.qian@gmail.com) for suggesting this change, which makes some conversions faster. 20151020 dtoa.c: add a test for dtoa() to return "1" under mode 4 when converting some very small powers of 10, such as 1e-322 with ndigits = 4 and 1e-319 with ndigits = 7 (examples provided by jay.foad@gmail.com). 20160219 gdtoa.tgz: Adjust gdtoa(...,mode,...) to assume "round near" when mode is 0 or 1. Make various tweaks to banish (useless) warnings from "gcc -Wall -Wextra". Thanks to Jarkko Hietaniemi <jhi@iki.fi> for advocating the latter exercise (and correcting a typo in README). 20160307 dtoa.c: fix glitches with floating-point values in hexadecimal notation: some values that should overflow to (appropriately signed) Infinity, such as 0x1p1025, were mishandled, and values greater than 0x1p-1075 and less than 0x1.0000000000001p-1075 where treated as zero rather than the smallest denormal number. gdtoa.tgz: fix a bug with hexadecimal input greater than the smallest denormal and less than the smallest denormal times the smallest number greater than one. In round-to-nearest values, such values should round to the smallest denormal rather than to zero. Thanks to Albert Chan <albertmcchan@yahoo.com> for bug reports. 20160325 dtoa.c: fix a bug whereby dtoa(...,mode,...) with, e.g., mode = 2 or 3 could return a string with trailing zeros, contrary to specification. An example provided by Albert Chan: dtoa(81320560005., 2, 10,...). gdtoa.tgz: fix the analogous bug in gdtoa/dtoa.c and gdtoa/gdtoa.c and apply the bug fix of 20151020 to gdtoa/dtoa.c. 20160429 dtoa.c, gdtoa.tgz (file dtoa.c): Fix a bug with dtoa mode 0 when Honor_FLT_ROUNDS is defined: with some inputs and nondefault rounding modes (e.g., 1.23 with round toward zero), the returned string was off by one. When the new 64-bit integer logic is used, the test in question is very unlikely to be used. This is another bug reported by Albert Chan. 20160505 dtoa.c: fix some glitches in strtod() when Honor_FLT_ROUNDS is defined: zero was returned for some decimal values that should have been rounded to +- the smallest denormal, and +-Infinity was returned for some hexadecimal strings with huge values that should have been rounded to +- the largest finite value. 20160506 gdtoa.tgz: analogous bug fixes to those of 20160505. 20180730 strtodg.c in gdtoa.c: fix a glitch, introduced 20160506, with some return values of +-Infinity: the STRTOG_Overflow bit was not set.
97 lines
2.9 KiB
C
97 lines
2.9 KiB
C
/****************************************************************
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The author of this software is David M. Gay.
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Copyright (C) 2004 by David M. Gay.
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All Rights Reserved
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Based on material in the rest of /netlib/fp/gdota.tar.gz,
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which is copyright (C) 1998, 2000 by Lucent Technologies.
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Permission to use, copy, modify, and distribute this software and
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its documentation for any purpose and without fee is hereby
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granted, provided that the above copyright notice appear in all
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copies and that both that the copyright notice and this
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permission notice and warranty disclaimer appear in supporting
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documentation, and that the name of Lucent or any of its entities
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not be used in advertising or publicity pertaining to
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distribution of the software without specific, written prior
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permission.
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LUCENT DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
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INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS.
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IN NO EVENT SHALL LUCENT OR ANY OF ITS ENTITIES BE LIABLE FOR ANY
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SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
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WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER
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IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION,
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ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF
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THIS SOFTWARE.
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****************************************************************/
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/* This is a variant of strtod that works on Intel ia32 systems */
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/* with the default extended-precision arithmetic -- it does not */
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/* require setting the precision control to 53 bits. */
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/* Please send bug reports to David M. Gay (dmg at acm dot org,
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* with " at " changed at "@" and " dot " changed to "."). */
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#include "gdtoaimp.h"
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double __strtod (const char *s, char **sp)
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{
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static FPI fpi = { 53, 1-1023-53+1, 2046-1023-53+1, 1, SI, Int_max /*unused*/ };
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ULong bits[2];
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Long expo;
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int k;
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union { ULong L[2]; double d; } u;
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k = __strtodg (s, sp, &fpi, &expo, bits);
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switch(k & STRTOG_Retmask) {
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case STRTOG_NoNumber:
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case STRTOG_Zero:
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u.L[0] = u.L[1] = 0;
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break;
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case STRTOG_Normal:
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u.L[_1] = bits[0];
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u.L[_0] = (bits[1] & ~0x100000) | ((expo + 0x3ff + 52) << 20);
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break;
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case STRTOG_Denormal:
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u.L[_1] = bits[0];
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u.L[_0] = bits[1];
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break;
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case STRTOG_Infinite:
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u.L[_0] = 0x7ff00000;
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u.L[_1] = 0;
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break;
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case STRTOG_NaN:
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u.L[_1] = d_QNAN0;
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u.L[_0] = d_QNAN1;
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break;
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case STRTOG_NaNbits:
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u.L[_0] = 0x7ff00000 | bits[1];
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u.L[_1] = bits[0];
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}
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if (k & STRTOG_Neg)
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u.L[_0] |= 0x80000000L;
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return u.d;
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}
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double __cdecl
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__mingw_strtod (const char * __restrict__ src, char ** __restrict__ endptr)
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__attribute__((alias("__strtod")));
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#if !(defined(_AMD64_) || defined(__x86_64__) || \
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defined(_X86_) || defined(__i386__))
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/* For systems other than x86, where long double == double, provide the
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* long double functions as aliases to __strtod. */
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long double __cdecl
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__mingw_strtold (const char * __restrict__ src, char ** __restrict__ endptr)
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__attribute__((alias("__strtod")));
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#endif
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