mirror of
https://sourceware.org/git/binutils-gdb.git
synced 2024-12-03 04:12:10 +08:00
fd67aa1129
Adds two new external authors to etc/update-copyright.py to cover bfd/ax_tls.m4, and adds gprofng to dirs handled automatically, then updates copyright messages as follows: 1) Update cgen/utils.scm emitted copyrights. 2) Run "etc/update-copyright.py --this-year" with an extra external author I haven't committed, 'Kalray SA.', to cover gas testsuite files (which should have their copyright message removed). 3) Build with --enable-maintainer-mode --enable-cgen-maint=yes. 4) Check out */po/*.pot which we don't update frequently.
793 lines
22 KiB
C
793 lines
22 KiB
C
/* IEEE floating point support routines, for GDB, the GNU Debugger.
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Copyright (C) 1991-2024 Free Software Foundation, Inc.
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This file is part of GDB.
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This program 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 2 of the License, or
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(at your option) any later version.
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This program 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 this program; if not, write to the Free Software
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Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA. */
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/* This is needed to pick up the NAN macro on some systems. */
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#ifndef _GNU_SOURCE
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#define _GNU_SOURCE
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#endif
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#ifdef HAVE_CONFIG_H
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#include "config.h"
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#endif
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#include <math.h>
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#ifdef HAVE_STRING_H
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#include <string.h>
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#endif
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/* On some platforms, <float.h> provides DBL_QNAN. */
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#ifdef STDC_HEADERS
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#include <float.h>
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#endif
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#include "ansidecl.h"
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#include "libiberty.h"
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#include "floatformat.h"
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#ifndef INFINITY
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#ifdef HUGE_VAL
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#define INFINITY HUGE_VAL
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#else
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#define INFINITY (1.0 / 0.0)
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#endif
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#endif
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#ifndef NAN
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#ifdef DBL_QNAN
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#define NAN DBL_QNAN
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#else
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#define NAN (0.0 / 0.0)
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#endif
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#endif
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static int mant_bits_set (const struct floatformat *, const unsigned char *);
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static unsigned long get_field (const unsigned char *,
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enum floatformat_byteorders,
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unsigned int,
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unsigned int,
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unsigned int);
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static int floatformat_always_valid (const struct floatformat *fmt,
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const void *from);
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static int
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floatformat_always_valid (const struct floatformat *fmt ATTRIBUTE_UNUSED,
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const void *from ATTRIBUTE_UNUSED)
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{
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return 1;
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}
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/* The odds that CHAR_BIT will be anything but 8 are low enough that I'm not
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going to bother with trying to muck around with whether it is defined in
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a system header, what we do if not, etc. */
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#define FLOATFORMAT_CHAR_BIT 8
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/* floatformats for IEEE half, single, double and quad, big and little endian. */
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const struct floatformat floatformat_ieee_half_big =
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{
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floatformat_big, 16, 0, 1, 5, 15, 31, 6, 10,
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floatformat_intbit_no,
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"floatformat_ieee_half_big",
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floatformat_always_valid,
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NULL
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};
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const struct floatformat floatformat_ieee_half_little =
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{
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floatformat_little, 16, 0, 1, 5, 15, 31, 6, 10,
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floatformat_intbit_no,
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"floatformat_ieee_half_little",
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floatformat_always_valid,
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NULL
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};
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const struct floatformat floatformat_ieee_single_big =
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{
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floatformat_big, 32, 0, 1, 8, 127, 255, 9, 23,
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floatformat_intbit_no,
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"floatformat_ieee_single_big",
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floatformat_always_valid,
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NULL
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};
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const struct floatformat floatformat_ieee_single_little =
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{
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floatformat_little, 32, 0, 1, 8, 127, 255, 9, 23,
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floatformat_intbit_no,
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"floatformat_ieee_single_little",
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floatformat_always_valid,
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NULL
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};
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const struct floatformat floatformat_ieee_double_big =
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{
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floatformat_big, 64, 0, 1, 11, 1023, 2047, 12, 52,
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floatformat_intbit_no,
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"floatformat_ieee_double_big",
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floatformat_always_valid,
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NULL
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};
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const struct floatformat floatformat_ieee_double_little =
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{
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floatformat_little, 64, 0, 1, 11, 1023, 2047, 12, 52,
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floatformat_intbit_no,
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"floatformat_ieee_double_little",
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floatformat_always_valid,
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NULL
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};
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const struct floatformat floatformat_ieee_quad_big =
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{
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floatformat_big, 128, 0, 1, 15, 16383, 0x7fff, 16, 112,
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floatformat_intbit_no,
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"floatformat_ieee_quad_big",
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floatformat_always_valid,
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NULL
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};
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const struct floatformat floatformat_ieee_quad_little =
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{
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floatformat_little, 128, 0, 1, 15, 16383, 0x7fff, 16, 112,
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floatformat_intbit_no,
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"floatformat_ieee_quad_little",
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floatformat_always_valid,
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NULL
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};
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/* floatformat for IEEE double, little endian byte order, with big endian word
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ordering, as on the ARM. */
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const struct floatformat floatformat_ieee_double_littlebyte_bigword =
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{
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floatformat_littlebyte_bigword, 64, 0, 1, 11, 1023, 2047, 12, 52,
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floatformat_intbit_no,
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"floatformat_ieee_double_littlebyte_bigword",
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floatformat_always_valid,
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NULL
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};
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/* floatformat for VAX. Not quite IEEE, but close enough. */
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const struct floatformat floatformat_vax_f =
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{
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floatformat_vax, 32, 0, 1, 8, 129, 0, 9, 23,
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floatformat_intbit_no,
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"floatformat_vax_f",
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floatformat_always_valid,
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NULL
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};
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const struct floatformat floatformat_vax_d =
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{
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floatformat_vax, 64, 0, 1, 8, 129, 0, 9, 55,
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floatformat_intbit_no,
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"floatformat_vax_d",
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floatformat_always_valid,
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NULL
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};
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const struct floatformat floatformat_vax_g =
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{
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floatformat_vax, 64, 0, 1, 11, 1025, 0, 12, 52,
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floatformat_intbit_no,
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"floatformat_vax_g",
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floatformat_always_valid,
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NULL
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};
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static int floatformat_i387_ext_is_valid (const struct floatformat *fmt,
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const void *from);
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static int
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floatformat_i387_ext_is_valid (const struct floatformat *fmt, const void *from)
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{
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/* In the i387 double-extended format, if the exponent is all ones,
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then the integer bit must be set. If the exponent is neither 0
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nor ~0, the intbit must also be set. Only if the exponent is
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zero can it be zero, and then it must be zero. */
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unsigned long exponent, int_bit;
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const unsigned char *ufrom = (const unsigned char *) from;
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exponent = get_field (ufrom, fmt->byteorder, fmt->totalsize,
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fmt->exp_start, fmt->exp_len);
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int_bit = get_field (ufrom, fmt->byteorder, fmt->totalsize,
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fmt->man_start, 1);
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if ((exponent == 0) != (int_bit == 0))
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return 0;
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else
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return 1;
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}
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const struct floatformat floatformat_i387_ext =
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{
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floatformat_little, 80, 0, 1, 15, 0x3fff, 0x7fff, 16, 64,
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floatformat_intbit_yes,
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"floatformat_i387_ext",
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floatformat_i387_ext_is_valid,
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NULL
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};
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const struct floatformat floatformat_m68881_ext =
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{
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/* Note that the bits from 16 to 31 are unused. */
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floatformat_big, 96, 0, 1, 15, 0x3fff, 0x7fff, 32, 64,
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floatformat_intbit_yes,
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"floatformat_m68881_ext",
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floatformat_always_valid,
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NULL
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};
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const struct floatformat floatformat_i960_ext =
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{
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/* Note that the bits from 0 to 15 are unused. */
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floatformat_little, 96, 16, 17, 15, 0x3fff, 0x7fff, 32, 64,
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floatformat_intbit_yes,
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"floatformat_i960_ext",
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floatformat_always_valid,
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NULL
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};
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const struct floatformat floatformat_m88110_ext =
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{
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floatformat_big, 80, 0, 1, 15, 0x3fff, 0x7fff, 16, 64,
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floatformat_intbit_yes,
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"floatformat_m88110_ext",
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floatformat_always_valid,
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NULL
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};
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const struct floatformat floatformat_m88110_harris_ext =
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{
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/* Harris uses raw format 128 bytes long, but the number is just an ieee
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double, and the last 64 bits are wasted. */
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floatformat_big,128, 0, 1, 11, 0x3ff, 0x7ff, 12, 52,
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floatformat_intbit_no,
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"floatformat_m88110_ext_harris",
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floatformat_always_valid,
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NULL
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};
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const struct floatformat floatformat_arm_ext_big =
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{
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/* Bits 1 to 16 are unused. */
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floatformat_big, 96, 0, 17, 15, 0x3fff, 0x7fff, 32, 64,
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floatformat_intbit_yes,
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"floatformat_arm_ext_big",
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floatformat_always_valid,
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NULL
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};
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const struct floatformat floatformat_arm_ext_littlebyte_bigword =
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{
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/* Bits 1 to 16 are unused. */
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floatformat_littlebyte_bigword, 96, 0, 17, 15, 0x3fff, 0x7fff, 32, 64,
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floatformat_intbit_yes,
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"floatformat_arm_ext_littlebyte_bigword",
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floatformat_always_valid,
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NULL
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};
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const struct floatformat floatformat_ia64_spill_big =
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{
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floatformat_big, 128, 0, 1, 17, 65535, 0x1ffff, 18, 64,
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floatformat_intbit_yes,
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"floatformat_ia64_spill_big",
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floatformat_always_valid,
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NULL
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};
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const struct floatformat floatformat_ia64_spill_little =
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{
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floatformat_little, 128, 0, 1, 17, 65535, 0x1ffff, 18, 64,
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floatformat_intbit_yes,
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"floatformat_ia64_spill_little",
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floatformat_always_valid,
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NULL
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};
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static int
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floatformat_ibm_long_double_is_valid (const struct floatformat *fmt,
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const void *from)
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{
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const unsigned char *ufrom = (const unsigned char *) from;
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const struct floatformat *hfmt = fmt->split_half;
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long top_exp, bot_exp;
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int top_nan = 0;
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top_exp = get_field (ufrom, hfmt->byteorder, hfmt->totalsize,
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hfmt->exp_start, hfmt->exp_len);
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bot_exp = get_field (ufrom + 8, hfmt->byteorder, hfmt->totalsize,
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hfmt->exp_start, hfmt->exp_len);
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if ((unsigned long) top_exp == hfmt->exp_nan)
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top_nan = mant_bits_set (hfmt, ufrom);
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/* A NaN is valid with any low part. */
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if (top_nan)
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return 1;
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/* An infinity, zero or denormal requires low part 0 (positive or
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negative). */
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if ((unsigned long) top_exp == hfmt->exp_nan || top_exp == 0)
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{
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if (bot_exp != 0)
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return 0;
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return !mant_bits_set (hfmt, ufrom + 8);
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}
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/* The top part is now a finite normal value. The long double value
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is the sum of the two parts, and the top part must equal the
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result of rounding the long double value to nearest double. Thus
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the bottom part must be <= 0.5ulp of the top part in absolute
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value, and if it is < 0.5ulp then the long double is definitely
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valid. */
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if (bot_exp < top_exp - 53)
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return 1;
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if (bot_exp > top_exp - 53 && bot_exp != 0)
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return 0;
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if (bot_exp == 0)
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{
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/* The bottom part is 0 or denormal. Determine which, and if
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denormal the first two set bits. */
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int first_bit = -1, second_bit = -1, cur_bit;
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for (cur_bit = 0; (unsigned int) cur_bit < hfmt->man_len; cur_bit++)
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if (get_field (ufrom + 8, hfmt->byteorder, hfmt->totalsize,
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hfmt->man_start + cur_bit, 1))
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{
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if (first_bit == -1)
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first_bit = cur_bit;
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else
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{
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second_bit = cur_bit;
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break;
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}
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}
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/* Bottom part 0 is OK. */
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if (first_bit == -1)
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return 1;
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/* The real exponent of the bottom part is -first_bit. */
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if (-first_bit < top_exp - 53)
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return 1;
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if (-first_bit > top_exp - 53)
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return 0;
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/* The bottom part is at least 0.5ulp of the top part. For this
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to be OK, the bottom part must be exactly 0.5ulp (i.e. no
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more bits set) and the top part must have last bit 0. */
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if (second_bit != -1)
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return 0;
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return !get_field (ufrom, hfmt->byteorder, hfmt->totalsize,
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hfmt->man_start + hfmt->man_len - 1, 1);
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}
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else
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{
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/* The bottom part is at least 0.5ulp of the top part. For this
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to be OK, it must be exactly 0.5ulp (i.e. no explicit bits
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set) and the top part must have last bit 0. */
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if (get_field (ufrom, hfmt->byteorder, hfmt->totalsize,
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hfmt->man_start + hfmt->man_len - 1, 1))
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return 0;
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return !mant_bits_set (hfmt, ufrom + 8);
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}
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}
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const struct floatformat floatformat_ibm_long_double_big =
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{
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floatformat_big, 128, 0, 1, 11, 1023, 2047, 12, 52,
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floatformat_intbit_no,
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"floatformat_ibm_long_double_big",
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floatformat_ibm_long_double_is_valid,
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&floatformat_ieee_double_big
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};
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const struct floatformat floatformat_ibm_long_double_little =
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{
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floatformat_little, 128, 0, 1, 11, 1023, 2047, 12, 52,
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floatformat_intbit_no,
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"floatformat_ibm_long_double_little",
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floatformat_ibm_long_double_is_valid,
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&floatformat_ieee_double_little
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};
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const struct floatformat floatformat_bfloat16_big =
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{
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floatformat_big, 16, 0, 1, 8, 127, 255, 9, 7,
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floatformat_intbit_no,
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"floatformat_bfloat16_big",
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floatformat_always_valid,
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NULL
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};
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const struct floatformat floatformat_bfloat16_little =
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{
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floatformat_little, 16, 0, 1, 8, 127, 255, 9, 7,
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floatformat_intbit_no,
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"floatformat_bfloat16_little",
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floatformat_always_valid,
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NULL
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};
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#ifndef min
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#define min(a, b) ((a) < (b) ? (a) : (b))
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#endif
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/* Return 1 if any bits are explicitly set in the mantissa of UFROM,
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format FMT, 0 otherwise. */
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static int
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mant_bits_set (const struct floatformat *fmt, const unsigned char *ufrom)
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{
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unsigned int mant_bits, mant_off;
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int mant_bits_left;
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mant_off = fmt->man_start;
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mant_bits_left = fmt->man_len;
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while (mant_bits_left > 0)
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{
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mant_bits = min (mant_bits_left, 32);
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if (get_field (ufrom, fmt->byteorder, fmt->totalsize,
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mant_off, mant_bits) != 0)
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return 1;
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mant_off += mant_bits;
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mant_bits_left -= mant_bits;
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}
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return 0;
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}
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/* Extract a field which starts at START and is LEN bits long. DATA and
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TOTAL_LEN are the thing we are extracting it from, in byteorder ORDER. */
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static unsigned long
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get_field (const unsigned char *data, enum floatformat_byteorders order,
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unsigned int total_len, unsigned int start, unsigned int len)
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{
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unsigned long result = 0;
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unsigned int cur_byte;
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int lo_bit, hi_bit, cur_bitshift = 0;
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int nextbyte = (order == floatformat_little) ? 1 : -1;
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/* Start is in big-endian bit order! Fix that first. */
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start = total_len - (start + len);
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/* Start at the least significant part of the field. */
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if (order == floatformat_little)
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cur_byte = start / FLOATFORMAT_CHAR_BIT;
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else
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cur_byte = (total_len - start - 1) / FLOATFORMAT_CHAR_BIT;
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lo_bit = start % FLOATFORMAT_CHAR_BIT;
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hi_bit = min (lo_bit + len, FLOATFORMAT_CHAR_BIT);
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do
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{
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unsigned int shifted = *(data + cur_byte) >> lo_bit;
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unsigned int bits = hi_bit - lo_bit;
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unsigned int mask = (1 << bits) - 1;
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result |= (shifted & mask) << cur_bitshift;
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len -= bits;
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cur_bitshift += bits;
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cur_byte += nextbyte;
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lo_bit = 0;
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hi_bit = min (len, FLOATFORMAT_CHAR_BIT);
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}
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while (len != 0);
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return result;
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}
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/* Convert from FMT to a double.
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FROM is the address of the extended float.
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Store the double in *TO. */
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void
|
||
floatformat_to_double (const struct floatformat *fmt,
|
||
const void *from, double *to)
|
||
{
|
||
const unsigned char *ufrom = (const unsigned char *) from;
|
||
double dto;
|
||
long exponent;
|
||
unsigned long mant;
|
||
unsigned int mant_bits, mant_off;
|
||
int mant_bits_left;
|
||
|
||
/* Split values are not handled specially, since the top half has
|
||
the correctly rounded double value (in the only supported case of
|
||
split values). */
|
||
|
||
exponent = get_field (ufrom, fmt->byteorder, fmt->totalsize,
|
||
fmt->exp_start, fmt->exp_len);
|
||
|
||
/* If the exponent indicates a NaN, we don't have information to
|
||
decide what to do. So we handle it like IEEE, except that we
|
||
don't try to preserve the type of NaN. FIXME. */
|
||
if ((unsigned long) exponent == fmt->exp_nan)
|
||
{
|
||
int nan = mant_bits_set (fmt, ufrom);
|
||
|
||
/* On certain systems (such as GNU/Linux), the use of the
|
||
INFINITY macro below may generate a warning that cannot be
|
||
silenced due to a bug in GCC (PR preprocessor/11931). The
|
||
preprocessor fails to recognise the __extension__ keyword in
|
||
conjunction with the GNU/C99 extension for hexadecimal
|
||
floating point constants and will issue a warning when
|
||
compiling with -pedantic. */
|
||
if (nan)
|
||
dto = NAN;
|
||
else
|
||
dto = INFINITY;
|
||
|
||
if (get_field (ufrom, fmt->byteorder, fmt->totalsize, fmt->sign_start, 1))
|
||
dto = -dto;
|
||
|
||
*to = dto;
|
||
|
||
return;
|
||
}
|
||
|
||
mant_bits_left = fmt->man_len;
|
||
mant_off = fmt->man_start;
|
||
dto = 0.0;
|
||
|
||
/* Build the result algebraically. Might go infinite, underflow, etc;
|
||
who cares. */
|
||
|
||
/* For denorms use minimum exponent. */
|
||
if (exponent == 0)
|
||
exponent = 1 - fmt->exp_bias;
|
||
else
|
||
{
|
||
exponent -= fmt->exp_bias;
|
||
|
||
/* If this format uses a hidden bit, explicitly add it in now.
|
||
Otherwise, increment the exponent by one to account for the
|
||
integer bit. */
|
||
|
||
if (fmt->intbit == floatformat_intbit_no)
|
||
dto = ldexp (1.0, exponent);
|
||
else
|
||
exponent++;
|
||
}
|
||
|
||
while (mant_bits_left > 0)
|
||
{
|
||
mant_bits = min (mant_bits_left, 32);
|
||
|
||
mant = get_field (ufrom, fmt->byteorder, fmt->totalsize,
|
||
mant_off, mant_bits);
|
||
|
||
dto += ldexp ((double) mant, exponent - mant_bits);
|
||
exponent -= mant_bits;
|
||
mant_off += mant_bits;
|
||
mant_bits_left -= mant_bits;
|
||
}
|
||
|
||
/* Negate it if negative. */
|
||
if (get_field (ufrom, fmt->byteorder, fmt->totalsize, fmt->sign_start, 1))
|
||
dto = -dto;
|
||
*to = dto;
|
||
}
|
||
|
||
static void put_field (unsigned char *, enum floatformat_byteorders,
|
||
unsigned int,
|
||
unsigned int,
|
||
unsigned int,
|
||
unsigned long);
|
||
|
||
/* Set a field which starts at START and is LEN bits long. DATA and
|
||
TOTAL_LEN are the thing we are extracting it from, in byteorder ORDER. */
|
||
static void
|
||
put_field (unsigned char *data, enum floatformat_byteorders order,
|
||
unsigned int total_len, unsigned int start, unsigned int len,
|
||
unsigned long stuff_to_put)
|
||
{
|
||
unsigned int cur_byte;
|
||
int lo_bit, hi_bit;
|
||
int nextbyte = (order == floatformat_little) ? 1 : -1;
|
||
|
||
/* Start is in big-endian bit order! Fix that first. */
|
||
start = total_len - (start + len);
|
||
|
||
/* Start at the least significant part of the field. */
|
||
if (order == floatformat_little)
|
||
cur_byte = start / FLOATFORMAT_CHAR_BIT;
|
||
else
|
||
cur_byte = (total_len - start - 1) / FLOATFORMAT_CHAR_BIT;
|
||
|
||
lo_bit = start % FLOATFORMAT_CHAR_BIT;
|
||
hi_bit = min (lo_bit + len, FLOATFORMAT_CHAR_BIT);
|
||
|
||
do
|
||
{
|
||
unsigned char *byte_ptr = data + cur_byte;
|
||
unsigned int bits = hi_bit - lo_bit;
|
||
unsigned int mask = ((1 << bits) - 1) << lo_bit;
|
||
*byte_ptr = (*byte_ptr & ~mask) | ((stuff_to_put << lo_bit) & mask);
|
||
stuff_to_put >>= bits;
|
||
len -= bits;
|
||
cur_byte += nextbyte;
|
||
lo_bit = 0;
|
||
hi_bit = min (len, FLOATFORMAT_CHAR_BIT);
|
||
}
|
||
while (len != 0);
|
||
}
|
||
|
||
/* The converse: convert the double *FROM to an extended float
|
||
and store where TO points. Neither FROM nor TO have any alignment
|
||
restrictions. */
|
||
|
||
void
|
||
floatformat_from_double (const struct floatformat *fmt,
|
||
const double *from, void *to)
|
||
{
|
||
double dfrom;
|
||
int exponent;
|
||
double mant;
|
||
unsigned int mant_bits, mant_off;
|
||
int mant_bits_left;
|
||
unsigned char *uto = (unsigned char *) to;
|
||
|
||
dfrom = *from;
|
||
memset (uto, 0, fmt->totalsize / FLOATFORMAT_CHAR_BIT);
|
||
|
||
/* Split values are not handled specially, since a bottom half of
|
||
zero is correct for any value representable as double (in the
|
||
only supported case of split values). */
|
||
|
||
/* If negative, set the sign bit. */
|
||
if (dfrom < 0)
|
||
{
|
||
put_field (uto, fmt->byteorder, fmt->totalsize, fmt->sign_start, 1, 1);
|
||
dfrom = -dfrom;
|
||
}
|
||
|
||
if (dfrom == 0)
|
||
{
|
||
/* 0.0. */
|
||
return;
|
||
}
|
||
|
||
if (dfrom != dfrom)
|
||
{
|
||
/* NaN. */
|
||
put_field (uto, fmt->byteorder, fmt->totalsize, fmt->exp_start,
|
||
fmt->exp_len, fmt->exp_nan);
|
||
/* Be sure it's not infinity, but NaN value is irrelevant. */
|
||
put_field (uto, fmt->byteorder, fmt->totalsize, fmt->man_start,
|
||
32, 1);
|
||
return;
|
||
}
|
||
|
||
if (dfrom + dfrom == dfrom)
|
||
{
|
||
/* This can only happen for an infinite value (or zero, which we
|
||
already handled above). */
|
||
put_field (uto, fmt->byteorder, fmt->totalsize, fmt->exp_start,
|
||
fmt->exp_len, fmt->exp_nan);
|
||
return;
|
||
}
|
||
|
||
mant = frexp (dfrom, &exponent);
|
||
if (exponent + fmt->exp_bias - 1 > 0)
|
||
put_field (uto, fmt->byteorder, fmt->totalsize, fmt->exp_start,
|
||
fmt->exp_len, exponent + fmt->exp_bias - 1);
|
||
else
|
||
{
|
||
/* Handle a denormalized number. FIXME: What should we do for
|
||
non-IEEE formats? */
|
||
put_field (uto, fmt->byteorder, fmt->totalsize, fmt->exp_start,
|
||
fmt->exp_len, 0);
|
||
mant = ldexp (mant, exponent + fmt->exp_bias - 1);
|
||
}
|
||
|
||
mant_bits_left = fmt->man_len;
|
||
mant_off = fmt->man_start;
|
||
while (mant_bits_left > 0)
|
||
{
|
||
unsigned long mant_long;
|
||
mant_bits = mant_bits_left < 32 ? mant_bits_left : 32;
|
||
|
||
mant *= 4294967296.0;
|
||
mant_long = (unsigned long)mant;
|
||
mant -= mant_long;
|
||
|
||
/* If the integer bit is implicit, and we are not creating a
|
||
denormalized number, then we need to discard it. */
|
||
if ((unsigned int) mant_bits_left == fmt->man_len
|
||
&& fmt->intbit == floatformat_intbit_no
|
||
&& exponent + fmt->exp_bias - 1 > 0)
|
||
{
|
||
mant_long &= 0x7fffffff;
|
||
mant_bits -= 1;
|
||
}
|
||
else if (mant_bits < 32)
|
||
{
|
||
/* The bits we want are in the most significant MANT_BITS bits of
|
||
mant_long. Move them to the least significant. */
|
||
mant_long >>= 32 - mant_bits;
|
||
}
|
||
|
||
put_field (uto, fmt->byteorder, fmt->totalsize,
|
||
mant_off, mant_bits, mant_long);
|
||
mant_off += mant_bits;
|
||
mant_bits_left -= mant_bits;
|
||
}
|
||
}
|
||
|
||
/* Return non-zero iff the data at FROM is a valid number in format FMT. */
|
||
|
||
int
|
||
floatformat_is_valid (const struct floatformat *fmt, const void *from)
|
||
{
|
||
return fmt->is_valid (fmt, from);
|
||
}
|
||
|
||
|
||
#ifdef IEEE_DEBUG
|
||
|
||
#include <stdio.h>
|
||
|
||
/* This is to be run on a host which uses IEEE floating point. */
|
||
|
||
void
|
||
ieee_test (double n)
|
||
{
|
||
double result;
|
||
|
||
floatformat_to_double (&floatformat_ieee_double_little, &n, &result);
|
||
if ((n != result && (! isnan (n) || ! isnan (result)))
|
||
|| (n < 0 && result >= 0)
|
||
|| (n >= 0 && result < 0))
|
||
printf ("Differ(to): %.20g -> %.20g\n", n, result);
|
||
|
||
floatformat_from_double (&floatformat_ieee_double_little, &n, &result);
|
||
if ((n != result && (! isnan (n) || ! isnan (result)))
|
||
|| (n < 0 && result >= 0)
|
||
|| (n >= 0 && result < 0))
|
||
printf ("Differ(from): %.20g -> %.20g\n", n, result);
|
||
|
||
#if 0
|
||
{
|
||
char exten[16];
|
||
|
||
floatformat_from_double (&floatformat_m68881_ext, &n, exten);
|
||
floatformat_to_double (&floatformat_m68881_ext, exten, &result);
|
||
if (n != result)
|
||
printf ("Differ(to+from): %.20g -> %.20g\n", n, result);
|
||
}
|
||
#endif
|
||
|
||
#if IEEE_DEBUG > 1
|
||
/* This is to be run on a host which uses 68881 format. */
|
||
{
|
||
long double ex = *(long double *)exten;
|
||
if (ex != n)
|
||
printf ("Differ(from vs. extended): %.20g\n", n);
|
||
}
|
||
#endif
|
||
}
|
||
|
||
int
|
||
main (void)
|
||
{
|
||
ieee_test (0.0);
|
||
ieee_test (0.5);
|
||
ieee_test (1.1);
|
||
ieee_test (256.0);
|
||
ieee_test (0.12345);
|
||
ieee_test (234235.78907234);
|
||
ieee_test (-512.0);
|
||
ieee_test (-0.004321);
|
||
ieee_test (1.2E-70);
|
||
ieee_test (1.2E-316);
|
||
ieee_test (4.9406564584124654E-324);
|
||
ieee_test (- 4.9406564584124654E-324);
|
||
ieee_test (- 0.0);
|
||
ieee_test (- INFINITY);
|
||
ieee_test (- NAN);
|
||
ieee_test (INFINITY);
|
||
ieee_test (NAN);
|
||
return 0;
|
||
}
|
||
#endif
|