forked from KolibriOS/kolibrios
813 lines
20 KiB
C
813 lines
20 KiB
C
/* atof_ieee.c - turn a Flonum into an IEEE floating point number
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Copyright (C) 1987-2015 Free Software Foundation, Inc.
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This file is part of GAS, the GNU Assembler.
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GAS is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 3, or (at your option)
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any later version.
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GAS is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with GAS; see the file COPYING. If not, write to the Free
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Software Foundation, 51 Franklin Street - Fifth Floor, Boston, MA
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02110-1301, USA. */
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#include "as.h"
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/* Flonums returned here. */
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extern FLONUM_TYPE generic_floating_point_number;
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extern const char EXP_CHARS[];
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/* Precision in LittleNums. */
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/* Don't count the gap in the m68k extended precision format. */
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#define MAX_PRECISION 5
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#define F_PRECISION 2
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#define D_PRECISION 4
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#define X_PRECISION 5
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#define P_PRECISION 5
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/* Length in LittleNums of guard bits. */
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#define GUARD 2
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#ifndef TC_LARGEST_EXPONENT_IS_NORMAL
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#define TC_LARGEST_EXPONENT_IS_NORMAL(PRECISION) 0
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#endif
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static const unsigned long mask[] =
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{
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0x00000000,
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0x00000001,
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0x00000003,
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0x00000007,
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0x0000000f,
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0x0000001f,
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0x0000003f,
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0x0000007f,
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0x000000ff,
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0x000001ff,
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0x000003ff,
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0x000007ff,
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0x00000fff,
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0x00001fff,
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0x00003fff,
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0x00007fff,
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0x0000ffff,
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0x0001ffff,
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0x0003ffff,
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0x0007ffff,
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0x000fffff,
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0x001fffff,
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0x003fffff,
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0x007fffff,
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0x00ffffff,
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0x01ffffff,
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0x03ffffff,
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0x07ffffff,
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0x0fffffff,
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0x1fffffff,
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0x3fffffff,
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0x7fffffff,
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0xffffffff,
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};
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static int bits_left_in_littlenum;
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static int littlenums_left;
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static LITTLENUM_TYPE *littlenum_pointer;
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static int
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next_bits (int number_of_bits)
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{
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int return_value;
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if (!littlenums_left)
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return 0;
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if (number_of_bits >= bits_left_in_littlenum)
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{
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return_value = mask[bits_left_in_littlenum] & *littlenum_pointer;
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number_of_bits -= bits_left_in_littlenum;
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return_value <<= number_of_bits;
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if (--littlenums_left)
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{
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bits_left_in_littlenum = LITTLENUM_NUMBER_OF_BITS - number_of_bits;
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--littlenum_pointer;
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return_value |=
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(*littlenum_pointer >> bits_left_in_littlenum)
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& mask[number_of_bits];
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}
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}
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else
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{
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bits_left_in_littlenum -= number_of_bits;
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return_value =
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mask[number_of_bits] & (*littlenum_pointer >> bits_left_in_littlenum);
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}
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return return_value;
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}
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/* Num had better be less than LITTLENUM_NUMBER_OF_BITS. */
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static void
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unget_bits (int num)
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{
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if (!littlenums_left)
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{
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++littlenum_pointer;
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++littlenums_left;
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bits_left_in_littlenum = num;
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}
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else if (bits_left_in_littlenum + num > LITTLENUM_NUMBER_OF_BITS)
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{
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bits_left_in_littlenum =
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num - (LITTLENUM_NUMBER_OF_BITS - bits_left_in_littlenum);
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++littlenum_pointer;
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++littlenums_left;
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}
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else
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bits_left_in_littlenum += num;
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}
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static void
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make_invalid_floating_point_number (LITTLENUM_TYPE *words)
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{
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as_bad (_("cannot create floating-point number"));
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/* Zero the leftmost bit. */
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words[0] = (LITTLENUM_TYPE) ((unsigned) -1) >> 1;
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words[1] = (LITTLENUM_TYPE) -1;
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words[2] = (LITTLENUM_TYPE) -1;
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words[3] = (LITTLENUM_TYPE) -1;
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words[4] = (LITTLENUM_TYPE) -1;
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words[5] = (LITTLENUM_TYPE) -1;
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}
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/* Warning: This returns 16-bit LITTLENUMs. It is up to the caller to
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figure out any alignment problems and to conspire for the
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bytes/word to be emitted in the right order. Bigendians beware! */
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/* Note that atof-ieee always has X and P precisions enabled. it is up
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to md_atof to filter them out if the target machine does not support
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them. */
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/* Returns pointer past text consumed. */
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char *
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atof_ieee (char *str, /* Text to convert to binary. */
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int what_kind, /* 'd', 'f', 'x', 'p'. */
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LITTLENUM_TYPE *words) /* Build the binary here. */
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{
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/* Extra bits for zeroed low-order bits.
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The 1st MAX_PRECISION are zeroed, the last contain flonum bits. */
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static LITTLENUM_TYPE bits[MAX_PRECISION + MAX_PRECISION + GUARD];
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char *return_value;
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/* Number of 16-bit words in the format. */
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int precision;
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long exponent_bits;
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FLONUM_TYPE save_gen_flonum;
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/* We have to save the generic_floating_point_number because it
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contains storage allocation about the array of LITTLENUMs where
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the value is actually stored. We will allocate our own array of
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littlenums below, but have to restore the global one on exit. */
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save_gen_flonum = generic_floating_point_number;
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return_value = str;
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generic_floating_point_number.low = bits + MAX_PRECISION;
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generic_floating_point_number.high = NULL;
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generic_floating_point_number.leader = NULL;
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generic_floating_point_number.exponent = 0;
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generic_floating_point_number.sign = '\0';
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/* Use more LittleNums than seems necessary: the highest flonum may
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have 15 leading 0 bits, so could be useless. */
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memset (bits, '\0', sizeof (LITTLENUM_TYPE) * MAX_PRECISION);
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switch (what_kind)
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{
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case 'f':
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case 'F':
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case 's':
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case 'S':
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precision = F_PRECISION;
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exponent_bits = 8;
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break;
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case 'd':
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case 'D':
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case 'r':
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case 'R':
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precision = D_PRECISION;
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exponent_bits = 11;
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break;
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case 'x':
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case 'X':
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case 'e':
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case 'E':
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precision = X_PRECISION;
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exponent_bits = 15;
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break;
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case 'p':
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case 'P':
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precision = P_PRECISION;
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exponent_bits = -1;
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break;
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default:
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make_invalid_floating_point_number (words);
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return (NULL);
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}
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generic_floating_point_number.high
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= generic_floating_point_number.low + precision - 1 + GUARD;
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if (atof_generic (&return_value, ".", EXP_CHARS,
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&generic_floating_point_number))
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{
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make_invalid_floating_point_number (words);
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return NULL;
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}
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gen_to_words (words, precision, exponent_bits);
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/* Restore the generic_floating_point_number's storage alloc (and
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everything else). */
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generic_floating_point_number = save_gen_flonum;
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return return_value;
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}
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/* Turn generic_floating_point_number into a real float/double/extended. */
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int
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gen_to_words (LITTLENUM_TYPE *words, int precision, long exponent_bits)
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{
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int return_value = 0;
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long exponent_1;
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long exponent_2;
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long exponent_3;
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long exponent_4;
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int exponent_skippage;
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LITTLENUM_TYPE word1;
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LITTLENUM_TYPE *lp;
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LITTLENUM_TYPE *words_end;
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words_end = words + precision;
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#ifdef TC_M68K
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if (precision == X_PRECISION)
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/* On the m68k the extended precision format has a gap of 16 bits
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between the exponent and the mantissa. */
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words_end++;
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#endif
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if (generic_floating_point_number.low > generic_floating_point_number.leader)
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{
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/* 0.0e0 seen. */
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if (generic_floating_point_number.sign == '+')
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words[0] = 0x0000;
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else
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words[0] = 0x8000;
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memset (&words[1], '\0',
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(words_end - words - 1) * sizeof (LITTLENUM_TYPE));
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return return_value;
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}
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/* NaN: Do the right thing. */
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if (generic_floating_point_number.sign == 0)
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{
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if (TC_LARGEST_EXPONENT_IS_NORMAL (precision))
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as_warn (_("NaNs are not supported by this target\n"));
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if (precision == F_PRECISION)
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{
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words[0] = 0x7fff;
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words[1] = 0xffff;
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}
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else if (precision == X_PRECISION)
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{
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#ifdef TC_M68K
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words[0] = 0x7fff;
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words[1] = 0;
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words[2] = 0xffff;
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words[3] = 0xffff;
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words[4] = 0xffff;
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words[5] = 0xffff;
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#else /* ! TC_M68K */
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#ifdef TC_I386
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words[0] = 0xffff;
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words[1] = 0xc000;
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words[2] = 0;
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words[3] = 0;
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words[4] = 0;
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#else /* ! TC_I386 */
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abort ();
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#endif /* ! TC_I386 */
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#endif /* ! TC_M68K */
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}
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else
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{
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words[0] = 0x7fff;
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words[1] = 0xffff;
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words[2] = 0xffff;
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words[3] = 0xffff;
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}
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return return_value;
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}
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else if (generic_floating_point_number.sign == 'P')
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{
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if (TC_LARGEST_EXPONENT_IS_NORMAL (precision))
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as_warn (_("Infinities are not supported by this target\n"));
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/* +INF: Do the right thing. */
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if (precision == F_PRECISION)
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{
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words[0] = 0x7f80;
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words[1] = 0;
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}
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else if (precision == X_PRECISION)
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{
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#ifdef TC_M68K
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words[0] = 0x7fff;
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words[1] = 0;
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words[2] = 0;
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words[3] = 0;
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words[4] = 0;
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words[5] = 0;
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#else /* ! TC_M68K */
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#ifdef TC_I386
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words[0] = 0x7fff;
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words[1] = 0x8000;
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words[2] = 0;
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words[3] = 0;
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words[4] = 0;
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#else /* ! TC_I386 */
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abort ();
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#endif /* ! TC_I386 */
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#endif /* ! TC_M68K */
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}
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else
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{
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words[0] = 0x7ff0;
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words[1] = 0;
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words[2] = 0;
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words[3] = 0;
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}
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return return_value;
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}
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else if (generic_floating_point_number.sign == 'N')
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{
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if (TC_LARGEST_EXPONENT_IS_NORMAL (precision))
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as_warn (_("Infinities are not supported by this target\n"));
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/* Negative INF. */
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if (precision == F_PRECISION)
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{
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words[0] = 0xff80;
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words[1] = 0x0;
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}
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else if (precision == X_PRECISION)
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{
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#ifdef TC_M68K
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words[0] = 0xffff;
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words[1] = 0;
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words[2] = 0;
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words[3] = 0;
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words[4] = 0;
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words[5] = 0;
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#else /* ! TC_M68K */
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#ifdef TC_I386
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words[0] = 0xffff;
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words[1] = 0x8000;
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words[2] = 0;
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words[3] = 0;
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words[4] = 0;
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#else /* ! TC_I386 */
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abort ();
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#endif /* ! TC_I386 */
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#endif /* ! TC_M68K */
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}
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else
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{
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words[0] = 0xfff0;
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words[1] = 0x0;
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words[2] = 0x0;
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words[3] = 0x0;
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}
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return return_value;
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}
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/* The floating point formats we support have:
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Bit 15 is sign bit.
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Bits 14:n are excess-whatever exponent.
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Bits n-1:0 (if any) are most significant bits of fraction.
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Bits 15:0 of the next word(s) are the next most significant bits.
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So we need: number of bits of exponent, number of bits of
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mantissa. */
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bits_left_in_littlenum = LITTLENUM_NUMBER_OF_BITS;
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littlenum_pointer = generic_floating_point_number.leader;
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littlenums_left = (1
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+ generic_floating_point_number.leader
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- generic_floating_point_number.low);
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/* Seek (and forget) 1st significant bit. */
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for (exponent_skippage = 0; !next_bits (1); ++exponent_skippage);
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exponent_1 = (generic_floating_point_number.exponent
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+ generic_floating_point_number.leader
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+ 1
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- generic_floating_point_number.low);
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/* Radix LITTLENUM_RADIX, point just higher than
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generic_floating_point_number.leader. */
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exponent_2 = exponent_1 * LITTLENUM_NUMBER_OF_BITS;
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/* Radix 2. */
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exponent_3 = exponent_2 - exponent_skippage;
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/* Forget leading zeros, forget 1st bit. */
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exponent_4 = exponent_3 + ((1 << (exponent_bits - 1)) - 2);
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/* Offset exponent. */
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lp = words;
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/* Word 1. Sign, exponent and perhaps high bits. */
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word1 = ((generic_floating_point_number.sign == '+')
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? 0
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: (1 << (LITTLENUM_NUMBER_OF_BITS - 1)));
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/* Assume 2's complement integers. */
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if (exponent_4 <= 0)
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{
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int prec_bits;
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int num_bits;
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unget_bits (1);
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num_bits = -exponent_4;
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prec_bits =
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LITTLENUM_NUMBER_OF_BITS * precision - (exponent_bits + 1 + num_bits);
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#ifdef TC_I386
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if (precision == X_PRECISION && exponent_bits == 15)
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{
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/* On the i386 a denormalized extended precision float is
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shifted down by one, effectively decreasing the exponent
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bias by one. */
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prec_bits -= 1;
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num_bits += 1;
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}
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#endif
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if (num_bits >= LITTLENUM_NUMBER_OF_BITS - exponent_bits)
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{
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/* Bigger than one littlenum. */
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num_bits -= (LITTLENUM_NUMBER_OF_BITS - 1) - exponent_bits;
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*lp++ = word1;
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if (num_bits + exponent_bits + 1
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> precision * LITTLENUM_NUMBER_OF_BITS)
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{
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/* Exponent overflow. */
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make_invalid_floating_point_number (words);
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return return_value;
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}
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#ifdef TC_M68K
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if (precision == X_PRECISION && exponent_bits == 15)
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*lp++ = 0;
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#endif
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while (num_bits >= LITTLENUM_NUMBER_OF_BITS)
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{
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num_bits -= LITTLENUM_NUMBER_OF_BITS;
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*lp++ = 0;
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}
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if (num_bits)
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*lp++ = next_bits (LITTLENUM_NUMBER_OF_BITS - (num_bits));
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}
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else
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{
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if (precision == X_PRECISION && exponent_bits == 15)
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{
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*lp++ = word1;
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#ifdef TC_M68K
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*lp++ = 0;
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#endif
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*lp++ = next_bits (LITTLENUM_NUMBER_OF_BITS - num_bits);
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}
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else
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{
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word1 |= next_bits ((LITTLENUM_NUMBER_OF_BITS - 1)
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- (exponent_bits + num_bits));
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*lp++ = word1;
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}
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}
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while (lp < words_end)
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*lp++ = next_bits (LITTLENUM_NUMBER_OF_BITS);
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/* Round the mantissa up, but don't change the number. */
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if (next_bits (1))
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{
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--lp;
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if (prec_bits >= LITTLENUM_NUMBER_OF_BITS)
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{
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int n = 0;
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int tmp_bits;
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n = 0;
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tmp_bits = prec_bits;
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while (tmp_bits > LITTLENUM_NUMBER_OF_BITS)
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{
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if (lp[n] != (LITTLENUM_TYPE) - 1)
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break;
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--n;
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tmp_bits -= LITTLENUM_NUMBER_OF_BITS;
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}
|
||
if (tmp_bits > LITTLENUM_NUMBER_OF_BITS
|
||
|| (lp[n] & mask[tmp_bits]) != mask[tmp_bits]
|
||
|| (prec_bits != (precision * LITTLENUM_NUMBER_OF_BITS
|
||
- exponent_bits - 1)
|
||
#ifdef TC_I386
|
||
/* An extended precision float with only the integer
|
||
bit set would be invalid. That must be converted
|
||
to the smallest normalized number. */
|
||
&& !(precision == X_PRECISION
|
||
&& prec_bits == (precision * LITTLENUM_NUMBER_OF_BITS
|
||
- exponent_bits - 2))
|
||
#endif
|
||
))
|
||
{
|
||
unsigned long carry;
|
||
|
||
for (carry = 1; carry && (lp >= words); lp--)
|
||
{
|
||
carry = *lp + carry;
|
||
*lp = carry;
|
||
carry >>= LITTLENUM_NUMBER_OF_BITS;
|
||
}
|
||
}
|
||
else
|
||
{
|
||
/* This is an overflow of the denormal numbers. We
|
||
need to forget what we have produced, and instead
|
||
generate the smallest normalized number. */
|
||
lp = words;
|
||
word1 = ((generic_floating_point_number.sign == '+')
|
||
? 0
|
||
: (1 << (LITTLENUM_NUMBER_OF_BITS - 1)));
|
||
word1 |= (1
|
||
<< ((LITTLENUM_NUMBER_OF_BITS - 1)
|
||
- exponent_bits));
|
||
*lp++ = word1;
|
||
#ifdef TC_I386
|
||
/* Set the integer bit in the extended precision format.
|
||
This cannot happen on the m68k where the mantissa
|
||
just overflows into the integer bit above. */
|
||
if (precision == X_PRECISION)
|
||
*lp++ = 1 << (LITTLENUM_NUMBER_OF_BITS - 1);
|
||
#endif
|
||
while (lp < words_end)
|
||
*lp++ = 0;
|
||
}
|
||
}
|
||
else
|
||
*lp += 1;
|
||
}
|
||
|
||
return return_value;
|
||
}
|
||
else if ((unsigned long) exponent_4 > mask[exponent_bits]
|
||
|| (! TC_LARGEST_EXPONENT_IS_NORMAL (precision)
|
||
&& (unsigned long) exponent_4 == mask[exponent_bits]))
|
||
{
|
||
/* Exponent overflow. Lose immediately. */
|
||
|
||
/* We leave return_value alone: admit we read the
|
||
number, but return a floating exception
|
||
because we can't encode the number. */
|
||
make_invalid_floating_point_number (words);
|
||
return return_value;
|
||
}
|
||
else
|
||
{
|
||
word1 |= (exponent_4 << ((LITTLENUM_NUMBER_OF_BITS - 1) - exponent_bits))
|
||
| next_bits ((LITTLENUM_NUMBER_OF_BITS - 1) - exponent_bits);
|
||
}
|
||
|
||
*lp++ = word1;
|
||
|
||
/* X_PRECISION is special: on the 68k, it has 16 bits of zero in the
|
||
middle. Either way, it is then followed by a 1 bit. */
|
||
if (exponent_bits == 15 && precision == X_PRECISION)
|
||
{
|
||
#ifdef TC_M68K
|
||
*lp++ = 0;
|
||
#endif
|
||
*lp++ = (1 << (LITTLENUM_NUMBER_OF_BITS - 1)
|
||
| next_bits (LITTLENUM_NUMBER_OF_BITS - 1));
|
||
}
|
||
|
||
/* The rest of the words are just mantissa bits. */
|
||
while (lp < words_end)
|
||
*lp++ = next_bits (LITTLENUM_NUMBER_OF_BITS);
|
||
|
||
if (next_bits (1))
|
||
{
|
||
unsigned long carry;
|
||
/* Since the NEXT bit is a 1, round UP the mantissa.
|
||
The cunning design of these hidden-1 floats permits
|
||
us to let the mantissa overflow into the exponent, and
|
||
it 'does the right thing'. However, we lose if the
|
||
highest-order bit of the lowest-order word flips.
|
||
Is that clear? */
|
||
|
||
/* #if (sizeof(carry)) < ((sizeof(bits[0]) * BITS_PER_CHAR) + 2)
|
||
Please allow at least 1 more bit in carry than is in a LITTLENUM.
|
||
We need that extra bit to hold a carry during a LITTLENUM carry
|
||
propagation. Another extra bit (kept 0) will assure us that we
|
||
don't get a sticky sign bit after shifting right, and that
|
||
permits us to propagate the carry without any masking of bits.
|
||
#endif */
|
||
for (carry = 1, lp--; carry; lp--)
|
||
{
|
||
carry = *lp + carry;
|
||
*lp = carry;
|
||
carry >>= LITTLENUM_NUMBER_OF_BITS;
|
||
if (lp == words)
|
||
break;
|
||
}
|
||
if (precision == X_PRECISION && exponent_bits == 15)
|
||
{
|
||
/* Extended precision numbers have an explicit integer bit
|
||
that we may have to restore. */
|
||
if (lp == words)
|
||
{
|
||
#ifdef TC_M68K
|
||
/* On the m68k there is a gap of 16 bits. We must
|
||
explicitly propagate the carry into the exponent. */
|
||
words[0] += words[1];
|
||
words[1] = 0;
|
||
lp++;
|
||
#endif
|
||
/* Put back the integer bit. */
|
||
lp[1] |= 1 << (LITTLENUM_NUMBER_OF_BITS - 1);
|
||
}
|
||
}
|
||
if ((word1 ^ *words) & (1 << (LITTLENUM_NUMBER_OF_BITS - 1)))
|
||
{
|
||
/* We leave return_value alone: admit we read the number,
|
||
but return a floating exception because we can't encode
|
||
the number. */
|
||
*words &= ~(1 << (LITTLENUM_NUMBER_OF_BITS - 1));
|
||
}
|
||
}
|
||
return return_value;
|
||
}
|
||
|
||
#ifdef TEST
|
||
char *
|
||
print_gen (gen)
|
||
FLONUM_TYPE *gen;
|
||
{
|
||
FLONUM_TYPE f;
|
||
LITTLENUM_TYPE arr[10];
|
||
double dv;
|
||
float fv;
|
||
static char sbuf[40];
|
||
|
||
if (gen)
|
||
{
|
||
f = generic_floating_point_number;
|
||
generic_floating_point_number = *gen;
|
||
}
|
||
gen_to_words (&arr[0], 4, 11);
|
||
memcpy (&dv, &arr[0], sizeof (double));
|
||
sprintf (sbuf, "%x %x %x %x %.14G ", arr[0], arr[1], arr[2], arr[3], dv);
|
||
gen_to_words (&arr[0], 2, 8);
|
||
memcpy (&fv, &arr[0], sizeof (float));
|
||
sprintf (sbuf + strlen (sbuf), "%x %x %.12g\n", arr[0], arr[1], fv);
|
||
|
||
if (gen)
|
||
generic_floating_point_number = f;
|
||
|
||
return (sbuf);
|
||
}
|
||
#endif
|
||
|
||
extern const char FLT_CHARS[];
|
||
#define MAX_LITTLENUMS 6
|
||
|
||
/* This is a utility function called from various tc-*.c files. It
|
||
is here in order to reduce code duplication.
|
||
|
||
Turn a string at input_line_pointer into a floating point constant
|
||
of type TYPE (a character found in the FLT_CHARS macro), and store
|
||
it as LITTLENUMS in the bytes buffer LITP. The number of chars
|
||
emitted is stored in *SIZEP. BIG_WORDIAN is TRUE if the littlenums
|
||
should be emitted most significant littlenum first.
|
||
|
||
An error message is returned, or a NULL pointer if everything went OK. */
|
||
|
||
char *
|
||
ieee_md_atof (int type,
|
||
char *litP,
|
||
int *sizeP,
|
||
bfd_boolean big_wordian)
|
||
{
|
||
LITTLENUM_TYPE words[MAX_LITTLENUMS];
|
||
LITTLENUM_TYPE *wordP;
|
||
char *t;
|
||
int prec = 0;
|
||
|
||
if (strchr (FLT_CHARS, type) != NULL)
|
||
{
|
||
switch (type)
|
||
{
|
||
case 'f':
|
||
case 'F':
|
||
case 's':
|
||
case 'S':
|
||
prec = F_PRECISION;
|
||
break;
|
||
|
||
case 'd':
|
||
case 'D':
|
||
case 'r':
|
||
case 'R':
|
||
prec = D_PRECISION;
|
||
break;
|
||
|
||
case 't':
|
||
case 'T':
|
||
prec = X_PRECISION;
|
||
type = 'x'; /* This is what atof_ieee() understands. */
|
||
break;
|
||
|
||
case 'x':
|
||
case 'X':
|
||
case 'p':
|
||
case 'P':
|
||
#ifdef TC_M68K
|
||
/* Note: on the m68k there is a gap of 16 bits (one littlenum)
|
||
between the exponent and mantissa. Hence the precision is
|
||
6 and not 5. */
|
||
prec = P_PRECISION + 1;
|
||
#else
|
||
prec = P_PRECISION;
|
||
#endif
|
||
break;
|
||
|
||
default:
|
||
break;
|
||
}
|
||
}
|
||
/* The 'f' and 'd' types are always recognised, even if the target has
|
||
not put them into the FLT_CHARS macro. This is because the 'f' type
|
||
can come from the .dc.s, .dcb.s, .float or .single pseudo-ops and the
|
||
'd' type from the .dc.d, .dbc.d or .double pseudo-ops.
|
||
|
||
The 'x' type is not implicitly recongised however, even though it can
|
||
be generated by the .dc.x and .dbc.x pseudo-ops because not all targets
|
||
can support floating point values that big. ie the target has to
|
||
explicitly allow them by putting them into FLT_CHARS. */
|
||
else if (type == 'f')
|
||
prec = F_PRECISION;
|
||
else if (type == 'd')
|
||
prec = D_PRECISION;
|
||
|
||
if (prec == 0)
|
||
{
|
||
*sizeP = 0;
|
||
return _("Unrecognized or unsupported floating point constant");
|
||
}
|
||
|
||
gas_assert (prec <= MAX_LITTLENUMS);
|
||
|
||
t = atof_ieee (input_line_pointer, type, words);
|
||
if (t)
|
||
input_line_pointer = t;
|
||
|
||
*sizeP = prec * sizeof (LITTLENUM_TYPE);
|
||
|
||
if (big_wordian)
|
||
{
|
||
for (wordP = words; prec --;)
|
||
{
|
||
md_number_to_chars (litP, (valueT) (* wordP ++), sizeof (LITTLENUM_TYPE));
|
||
litP += sizeof (LITTLENUM_TYPE);
|
||
}
|
||
}
|
||
else
|
||
{
|
||
for (wordP = words + prec; prec --;)
|
||
{
|
||
md_number_to_chars (litP, (valueT) (* -- wordP), sizeof (LITTLENUM_TYPE));
|
||
litP += sizeof (LITTLENUM_TYPE);
|
||
}
|
||
}
|
||
|
||
return NULL;
|
||
}
|