160 lines
4.3 KiB
C
160 lines
4.3 KiB
C
/* $OpenBSD: ldtoa.c,v 1.4 2016/03/09 16:28:47 deraadt Exp $ */
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/*-
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* Copyright (c) 2003 David Schultz <das@FreeBSD.ORG>
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* All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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*
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* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*/
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#include <newlib.h>
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#include <sys/config.h>
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#ifdef _USE_GDTOA
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#include <sys/types.h>
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#include <machine/ieee.h>
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#include <float.h>
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#include <stdint.h>
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#include <limits.h>
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#include <math.h>
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#include <stdlib.h>
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#include "gdtoaimp.h"
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#if (LDBL_MANT_DIG > DBL_MANT_DIG)
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/*
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* ldtoa() is a wrapper for gdtoa() that makes it smell like dtoa(),
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* except that the floating point argument is passed by reference.
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* When dtoa() is passed a NaN or infinity, it sets expt to 9999.
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* However, a long double could have a valid exponent of 9999, so we
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* use INT_MAX in ldtoa() instead.
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*/
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char *
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_ldtoa_r(struct _reent *ptr,
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long double ld, int mode, int ndigits, int *decpt, int *sign, char **rve)
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{
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FPI fpi = {
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LDBL_MANT_DIG, /* nbits */
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LDBL_MIN_EXP - LDBL_MANT_DIG, /* emin */
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LDBL_MAX_EXP - LDBL_MANT_DIG, /* emax */
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FLT_ROUNDS, /* rounding */
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#ifdef Sudden_Underflow /* unused, but correct anyway */
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1
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#else
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0
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#endif
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};
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int be, kind;
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char *ret;
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struct ieee_ext *p = (struct ieee_ext *)&ld;
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uint32_t bits[(LDBL_MANT_DIG + 31) / 32];
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void *vbits = bits;
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_REENT_CHECK_MP (ptr);
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/* reentrancy addition to use mprec storage pool */
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if (_REENT_MP_RESULT (ptr)) {
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_REENT_MP_RESULT (ptr)->_k = _REENT_MP_RESULT_K (ptr);
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_REENT_MP_RESULT (ptr)->_maxwds = 1 << _REENT_MP_RESULT_K (ptr);
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Bfree (ptr, _REENT_MP_RESULT (ptr));
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_REENT_MP_RESULT (ptr) = 0;
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}
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/*
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* gdtoa doesn't know anything about the sign of the number, so
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* if the number is negative, we need to swap rounding modes of
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* 2 (upwards) and 3 (downwards).
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*/
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*sign = p->ext_sign;
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fpi.rounding ^= (fpi.rounding >> 1) & p->ext_sign;
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be = p->ext_exp - (LDBL_MAX_EXP - 1) - (LDBL_MANT_DIG - 1);
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EXT_TO_ARRAY32(p, bits);
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switch (fpclassify(ld)) {
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case FP_NORMAL:
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kind = STRTOG_Normal;
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#ifdef EXT_IMPLICIT_NBIT
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bits[LDBL_MANT_DIG / 32] |= 1 << ((LDBL_MANT_DIG - 1) % 32);
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#endif /* EXT_IMPLICIT_NBIT */
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break;
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case FP_ZERO:
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kind = STRTOG_Zero;
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break;
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case FP_SUBNORMAL:
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kind = STRTOG_Denormal;
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be++;
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break;
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case FP_INFINITE:
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kind = STRTOG_Infinite;
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break;
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case FP_NAN:
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kind = STRTOG_NaN;
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break;
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default:
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abort();
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}
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ret = gdtoa(ptr, &fpi, be, vbits, &kind, mode, ndigits, decpt, rve);
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if (*decpt == -32768)
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*decpt = INT_MAX;
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return ret;
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}
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DEF_STRONG(_ldtoa_r);
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#else /* (LDBL_MANT_DIG == DBL_MANT_DIG) */
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char *
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_ldtoa_r(struct _reent *ptr,
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long double ld, int mode, int ndigits, int *decpt, int *sign,
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char **rve)
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{
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char *ret;
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ret = _dtoa_r(ptr, (double)ld, mode, ndigits, decpt, sign, rve);
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if (*decpt == 9999)
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*decpt = INT_MAX;
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return ret;
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}
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DEF_STRONG(_ldtoa_r);
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#endif /* (LDBL_MANT_DIG == DBL_MANT_DIG) */
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/* Routine used to tell if long double is NaN or Infinity or regular number.
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Returns: 0 = regular number
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1 = Nan
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2 = Infinity
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*/
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int
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_ldcheck (long double *d)
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{
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switch (fpclassify(*d)) {
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case FP_NAN:
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return 1;
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case FP_INFINITE:
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return 2;
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default:
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return 0;
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}
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}
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#endif /* _USE_GDTOA */
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