nkeynes@1265 | 1 | /* IEEE floating point support routines, for GDB, the GNU Debugger.
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nkeynes@1265 | 2 | Copyright 1991, 1994, 1999, 2000, 2003, 2005, 2006, 2010
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nkeynes@1265 | 3 | Free Software Foundation, Inc.
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nkeynes@1265 | 4 |
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nkeynes@1265 | 5 | This file is part of GDB.
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nkeynes@1265 | 6 |
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nkeynes@1265 | 7 | This program is free software; you can redistribute it and/or modify
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nkeynes@1265 | 8 | it under the terms of the GNU General Public License as published by
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nkeynes@1265 | 9 | the Free Software Foundation; either version 2 of the License, or
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nkeynes@1265 | 10 | (at your option) any later version.
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nkeynes@1265 | 11 |
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nkeynes@1265 | 12 | This program is distributed in the hope that it will be useful,
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nkeynes@1265 | 13 | but WITHOUT ANY WARRANTY; without even the implied warranty of
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nkeynes@1265 | 14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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nkeynes@1265 | 15 | GNU General Public License for more details.
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nkeynes@1265 | 16 |
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nkeynes@1265 | 17 | You should have received a copy of the GNU General Public License
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nkeynes@1265 | 18 | along with this program; if not, write to the Free Software
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nkeynes@1265 | 19 | Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston, MA 02110-1301, USA. */
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nkeynes@1265 | 20 |
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nkeynes@1265 | 21 | #ifdef HAVE_CONFIG_H
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nkeynes@1265 | 22 | #include "config.h"
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nkeynes@1265 | 23 | #endif
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nkeynes@1265 | 24 |
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nkeynes@1265 | 25 | #include <math.h>
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nkeynes@1265 | 26 |
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nkeynes@1265 | 27 | #ifdef HAVE_STRING_H
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nkeynes@1265 | 28 | #include <string.h>
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nkeynes@1265 | 29 | #endif
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nkeynes@1265 | 30 |
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nkeynes@1265 | 31 | /* On some platforms, <float.h> provides DBL_QNAN. */
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nkeynes@1265 | 32 | #ifdef STDC_HEADERS
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nkeynes@1265 | 33 | #include <float.h>
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nkeynes@1265 | 34 | #endif
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nkeynes@1265 | 35 |
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nkeynes@1265 | 36 | #include "ansidecl.h"
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nkeynes@1265 | 37 | #include "floatformat.h"
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nkeynes@1265 | 38 |
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nkeynes@1265 | 39 | #ifndef INFINITY
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nkeynes@1265 | 40 | #ifdef HUGE_VAL
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nkeynes@1265 | 41 | #define INFINITY HUGE_VAL
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nkeynes@1265 | 42 | #else
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nkeynes@1265 | 43 | #define INFINITY (1.0 / 0.0)
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nkeynes@1265 | 44 | #endif
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nkeynes@1265 | 45 | #endif
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nkeynes@1265 | 46 |
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nkeynes@1265 | 47 | #ifndef NAN
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nkeynes@1265 | 48 | #ifdef DBL_QNAN
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nkeynes@1265 | 49 | #define NAN DBL_QNAN
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nkeynes@1265 | 50 | #else
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nkeynes@1265 | 51 | #define NAN (0.0 / 0.0)
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nkeynes@1265 | 52 | #endif
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nkeynes@1265 | 53 | #endif
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nkeynes@1265 | 54 |
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nkeynes@1265 | 55 | static int mant_bits_set (const struct floatformat *, const unsigned char *);
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nkeynes@1265 | 56 | static unsigned long get_field (const unsigned char *,
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nkeynes@1265 | 57 | enum floatformat_byteorders,
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nkeynes@1265 | 58 | unsigned int,
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nkeynes@1265 | 59 | unsigned int,
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nkeynes@1265 | 60 | unsigned int);
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nkeynes@1265 | 61 | static int floatformat_always_valid (const struct floatformat *fmt,
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nkeynes@1265 | 62 | const void *from);
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nkeynes@1265 | 63 |
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nkeynes@1265 | 64 | static int
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nkeynes@1265 | 65 | floatformat_always_valid (const struct floatformat *fmt ATTRIBUTE_UNUSED,
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nkeynes@1265 | 66 | const void *from ATTRIBUTE_UNUSED)
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nkeynes@1265 | 67 | {
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nkeynes@1265 | 68 | return 1;
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nkeynes@1265 | 69 | }
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nkeynes@1265 | 70 |
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nkeynes@1265 | 71 | /* The odds that CHAR_BIT will be anything but 8 are low enough that I'm not
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nkeynes@1265 | 72 | going to bother with trying to muck around with whether it is defined in
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nkeynes@1265 | 73 | a system header, what we do if not, etc. */
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nkeynes@1265 | 74 | #define FLOATFORMAT_CHAR_BIT 8
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nkeynes@1265 | 75 |
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nkeynes@1265 | 76 | /* floatformats for IEEE half, single and double, big and little endian. */
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nkeynes@1265 | 77 | const struct floatformat floatformat_ieee_half_big =
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nkeynes@1265 | 78 | {
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nkeynes@1265 | 79 | floatformat_big, 16, 0, 1, 5, 15, 31, 6, 10,
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nkeynes@1265 | 80 | floatformat_intbit_no,
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nkeynes@1265 | 81 | "floatformat_ieee_half_big",
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nkeynes@1265 | 82 | floatformat_always_valid,
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nkeynes@1265 | 83 | NULL
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nkeynes@1265 | 84 | };
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nkeynes@1265 | 85 | const struct floatformat floatformat_ieee_half_little =
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nkeynes@1265 | 86 | {
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nkeynes@1265 | 87 | floatformat_little, 16, 0, 1, 5, 15, 31, 6, 10,
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nkeynes@1265 | 88 | floatformat_intbit_no,
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nkeynes@1265 | 89 | "floatformat_ieee_half_little",
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nkeynes@1265 | 90 | floatformat_always_valid,
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nkeynes@1265 | 91 | NULL
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nkeynes@1265 | 92 | };
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nkeynes@1265 | 93 | const struct floatformat floatformat_ieee_single_big =
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nkeynes@1265 | 94 | {
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nkeynes@1265 | 95 | floatformat_big, 32, 0, 1, 8, 127, 255, 9, 23,
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nkeynes@1265 | 96 | floatformat_intbit_no,
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nkeynes@1265 | 97 | "floatformat_ieee_single_big",
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nkeynes@1265 | 98 | floatformat_always_valid,
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nkeynes@1265 | 99 | NULL
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nkeynes@1265 | 100 | };
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nkeynes@1265 | 101 | const struct floatformat floatformat_ieee_single_little =
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nkeynes@1265 | 102 | {
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nkeynes@1265 | 103 | floatformat_little, 32, 0, 1, 8, 127, 255, 9, 23,
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nkeynes@1265 | 104 | floatformat_intbit_no,
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nkeynes@1265 | 105 | "floatformat_ieee_single_little",
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nkeynes@1265 | 106 | floatformat_always_valid,
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nkeynes@1265 | 107 | NULL
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nkeynes@1265 | 108 | };
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nkeynes@1265 | 109 | const struct floatformat floatformat_ieee_double_big =
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nkeynes@1265 | 110 | {
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nkeynes@1265 | 111 | floatformat_big, 64, 0, 1, 11, 1023, 2047, 12, 52,
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nkeynes@1265 | 112 | floatformat_intbit_no,
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nkeynes@1265 | 113 | "floatformat_ieee_double_big",
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nkeynes@1265 | 114 | floatformat_always_valid,
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nkeynes@1265 | 115 | NULL
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nkeynes@1265 | 116 | };
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nkeynes@1265 | 117 | const struct floatformat floatformat_ieee_double_little =
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nkeynes@1265 | 118 | {
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nkeynes@1265 | 119 | floatformat_little, 64, 0, 1, 11, 1023, 2047, 12, 52,
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nkeynes@1265 | 120 | floatformat_intbit_no,
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nkeynes@1265 | 121 | "floatformat_ieee_double_little",
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nkeynes@1265 | 122 | floatformat_always_valid,
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nkeynes@1265 | 123 | NULL
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nkeynes@1265 | 124 | };
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nkeynes@1265 | 125 |
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nkeynes@1265 | 126 | /* floatformat for IEEE double, little endian byte order, with big endian word
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nkeynes@1265 | 127 | ordering, as on the ARM. */
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nkeynes@1265 | 128 |
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nkeynes@1265 | 129 | const struct floatformat floatformat_ieee_double_littlebyte_bigword =
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nkeynes@1265 | 130 | {
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nkeynes@1265 | 131 | floatformat_littlebyte_bigword, 64, 0, 1, 11, 1023, 2047, 12, 52,
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nkeynes@1265 | 132 | floatformat_intbit_no,
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nkeynes@1265 | 133 | "floatformat_ieee_double_littlebyte_bigword",
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nkeynes@1265 | 134 | floatformat_always_valid,
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nkeynes@1265 | 135 | NULL
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nkeynes@1265 | 136 | };
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nkeynes@1265 | 137 |
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nkeynes@1265 | 138 | /* floatformat for VAX. Not quite IEEE, but close enough. */
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nkeynes@1265 | 139 |
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nkeynes@1265 | 140 | const struct floatformat floatformat_vax_f =
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nkeynes@1265 | 141 | {
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nkeynes@1265 | 142 | floatformat_vax, 32, 0, 1, 8, 129, 0, 9, 23,
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nkeynes@1265 | 143 | floatformat_intbit_no,
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nkeynes@1265 | 144 | "floatformat_vax_f",
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nkeynes@1265 | 145 | floatformat_always_valid,
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nkeynes@1265 | 146 | NULL
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nkeynes@1265 | 147 | };
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nkeynes@1265 | 148 | const struct floatformat floatformat_vax_d =
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nkeynes@1265 | 149 | {
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nkeynes@1265 | 150 | floatformat_vax, 64, 0, 1, 8, 129, 0, 9, 55,
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nkeynes@1265 | 151 | floatformat_intbit_no,
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nkeynes@1265 | 152 | "floatformat_vax_d",
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nkeynes@1265 | 153 | floatformat_always_valid,
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nkeynes@1265 | 154 | NULL
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nkeynes@1265 | 155 | };
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nkeynes@1265 | 156 | const struct floatformat floatformat_vax_g =
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nkeynes@1265 | 157 | {
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nkeynes@1265 | 158 | floatformat_vax, 64, 0, 1, 11, 1025, 0, 12, 52,
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nkeynes@1265 | 159 | floatformat_intbit_no,
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nkeynes@1265 | 160 | "floatformat_vax_g",
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nkeynes@1265 | 161 | floatformat_always_valid,
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nkeynes@1265 | 162 | NULL
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nkeynes@1265 | 163 | };
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nkeynes@1265 | 164 |
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nkeynes@1265 | 165 | static int floatformat_i387_ext_is_valid (const struct floatformat *fmt,
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nkeynes@1265 | 166 | const void *from);
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nkeynes@1265 | 167 |
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nkeynes@1265 | 168 | static int
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nkeynes@1265 | 169 | floatformat_i387_ext_is_valid (const struct floatformat *fmt, const void *from)
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nkeynes@1265 | 170 | {
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nkeynes@1265 | 171 | /* In the i387 double-extended format, if the exponent is all ones,
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nkeynes@1265 | 172 | then the integer bit must be set. If the exponent is neither 0
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nkeynes@1265 | 173 | nor ~0, the intbit must also be set. Only if the exponent is
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nkeynes@1265 | 174 | zero can it be zero, and then it must be zero. */
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nkeynes@1265 | 175 | unsigned long exponent, int_bit;
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nkeynes@1265 | 176 | const unsigned char *ufrom = (const unsigned char *) from;
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nkeynes@1265 | 177 |
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nkeynes@1265 | 178 | exponent = get_field (ufrom, fmt->byteorder, fmt->totalsize,
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nkeynes@1265 | 179 | fmt->exp_start, fmt->exp_len);
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nkeynes@1265 | 180 | int_bit = get_field (ufrom, fmt->byteorder, fmt->totalsize,
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nkeynes@1265 | 181 | fmt->man_start, 1);
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nkeynes@1265 | 182 |
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nkeynes@1265 | 183 | if ((exponent == 0) != (int_bit == 0))
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nkeynes@1265 | 184 | return 0;
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nkeynes@1265 | 185 | else
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nkeynes@1265 | 186 | return 1;
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nkeynes@1265 | 187 | }
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nkeynes@1265 | 188 |
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nkeynes@1265 | 189 | const struct floatformat floatformat_i387_ext =
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nkeynes@1265 | 190 | {
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nkeynes@1265 | 191 | floatformat_little, 80, 0, 1, 15, 0x3fff, 0x7fff, 16, 64,
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nkeynes@1265 | 192 | floatformat_intbit_yes,
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nkeynes@1265 | 193 | "floatformat_i387_ext",
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nkeynes@1265 | 194 | floatformat_i387_ext_is_valid,
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nkeynes@1265 | 195 | NULL
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nkeynes@1265 | 196 | };
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nkeynes@1265 | 197 | const struct floatformat floatformat_m68881_ext =
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nkeynes@1265 | 198 | {
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nkeynes@1265 | 199 | /* Note that the bits from 16 to 31 are unused. */
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nkeynes@1265 | 200 | floatformat_big, 96, 0, 1, 15, 0x3fff, 0x7fff, 32, 64,
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nkeynes@1265 | 201 | floatformat_intbit_yes,
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nkeynes@1265 | 202 | "floatformat_m68881_ext",
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nkeynes@1265 | 203 | floatformat_always_valid,
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nkeynes@1265 | 204 | NULL
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nkeynes@1265 | 205 | };
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nkeynes@1265 | 206 | const struct floatformat floatformat_i960_ext =
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nkeynes@1265 | 207 | {
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nkeynes@1265 | 208 | /* Note that the bits from 0 to 15 are unused. */
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nkeynes@1265 | 209 | floatformat_little, 96, 16, 17, 15, 0x3fff, 0x7fff, 32, 64,
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nkeynes@1265 | 210 | floatformat_intbit_yes,
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nkeynes@1265 | 211 | "floatformat_i960_ext",
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nkeynes@1265 | 212 | floatformat_always_valid,
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nkeynes@1265 | 213 | NULL
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nkeynes@1265 | 214 | };
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nkeynes@1265 | 215 | const struct floatformat floatformat_m88110_ext =
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nkeynes@1265 | 216 | {
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nkeynes@1265 | 217 | floatformat_big, 80, 0, 1, 15, 0x3fff, 0x7fff, 16, 64,
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nkeynes@1265 | 218 | floatformat_intbit_yes,
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nkeynes@1265 | 219 | "floatformat_m88110_ext",
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nkeynes@1265 | 220 | floatformat_always_valid,
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nkeynes@1265 | 221 | NULL
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nkeynes@1265 | 222 | };
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nkeynes@1265 | 223 | const struct floatformat floatformat_m88110_harris_ext =
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nkeynes@1265 | 224 | {
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nkeynes@1265 | 225 | /* Harris uses raw format 128 bytes long, but the number is just an ieee
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nkeynes@1265 | 226 | double, and the last 64 bits are wasted. */
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nkeynes@1265 | 227 | floatformat_big,128, 0, 1, 11, 0x3ff, 0x7ff, 12, 52,
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nkeynes@1265 | 228 | floatformat_intbit_no,
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nkeynes@1265 | 229 | "floatformat_m88110_ext_harris",
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nkeynes@1265 | 230 | floatformat_always_valid,
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nkeynes@1265 | 231 | NULL
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nkeynes@1265 | 232 | };
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nkeynes@1265 | 233 | const struct floatformat floatformat_arm_ext_big =
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nkeynes@1265 | 234 | {
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nkeynes@1265 | 235 | /* Bits 1 to 16 are unused. */
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nkeynes@1265 | 236 | floatformat_big, 96, 0, 17, 15, 0x3fff, 0x7fff, 32, 64,
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nkeynes@1265 | 237 | floatformat_intbit_yes,
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nkeynes@1265 | 238 | "floatformat_arm_ext_big",
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nkeynes@1265 | 239 | floatformat_always_valid,
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nkeynes@1265 | 240 | NULL
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nkeynes@1265 | 241 | };
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nkeynes@1265 | 242 | const struct floatformat floatformat_arm_ext_littlebyte_bigword =
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nkeynes@1265 | 243 | {
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nkeynes@1265 | 244 | /* Bits 1 to 16 are unused. */
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nkeynes@1265 | 245 | floatformat_littlebyte_bigword, 96, 0, 17, 15, 0x3fff, 0x7fff, 32, 64,
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nkeynes@1265 | 246 | floatformat_intbit_yes,
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nkeynes@1265 | 247 | "floatformat_arm_ext_littlebyte_bigword",
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nkeynes@1265 | 248 | floatformat_always_valid,
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nkeynes@1265 | 249 | NULL
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nkeynes@1265 | 250 | };
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nkeynes@1265 | 251 | const struct floatformat floatformat_ia64_spill_big =
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nkeynes@1265 | 252 | {
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nkeynes@1265 | 253 | floatformat_big, 128, 0, 1, 17, 65535, 0x1ffff, 18, 64,
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nkeynes@1265 | 254 | floatformat_intbit_yes,
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nkeynes@1265 | 255 | "floatformat_ia64_spill_big",
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nkeynes@1265 | 256 | floatformat_always_valid,
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nkeynes@1265 | 257 | NULL
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nkeynes@1265 | 258 | };
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nkeynes@1265 | 259 | const struct floatformat floatformat_ia64_spill_little =
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nkeynes@1265 | 260 | {
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nkeynes@1265 | 261 | floatformat_little, 128, 0, 1, 17, 65535, 0x1ffff, 18, 64,
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nkeynes@1265 | 262 | floatformat_intbit_yes,
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nkeynes@1265 | 263 | "floatformat_ia64_spill_little",
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nkeynes@1265 | 264 | floatformat_always_valid,
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nkeynes@1265 | 265 | NULL
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nkeynes@1265 | 266 | };
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nkeynes@1265 | 267 | const struct floatformat floatformat_ia64_quad_big =
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nkeynes@1265 | 268 | {
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nkeynes@1265 | 269 | floatformat_big, 128, 0, 1, 15, 16383, 0x7fff, 16, 112,
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nkeynes@1265 | 270 | floatformat_intbit_no,
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nkeynes@1265 | 271 | "floatformat_ia64_quad_big",
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nkeynes@1265 | 272 | floatformat_always_valid,
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nkeynes@1265 | 273 | NULL
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nkeynes@1265 | 274 | };
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nkeynes@1265 | 275 | const struct floatformat floatformat_ia64_quad_little =
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nkeynes@1265 | 276 | {
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nkeynes@1265 | 277 | floatformat_little, 128, 0, 1, 15, 16383, 0x7fff, 16, 112,
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nkeynes@1265 | 278 | floatformat_intbit_no,
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nkeynes@1265 | 279 | "floatformat_ia64_quad_little",
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nkeynes@1265 | 280 | floatformat_always_valid,
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nkeynes@1265 | 281 | NULL
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nkeynes@1265 | 282 | };
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nkeynes@1265 | 283 |
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nkeynes@1265 | 284 | static int
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nkeynes@1265 | 285 | floatformat_ibm_long_double_is_valid (const struct floatformat *fmt,
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nkeynes@1265 | 286 | const void *from)
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nkeynes@1265 | 287 | {
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nkeynes@1265 | 288 | const unsigned char *ufrom = (const unsigned char *) from;
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nkeynes@1265 | 289 | const struct floatformat *hfmt = fmt->split_half;
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nkeynes@1265 | 290 | long top_exp, bot_exp;
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nkeynes@1265 | 291 | int top_nan = 0;
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nkeynes@1265 | 292 |
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nkeynes@1265 | 293 | top_exp = get_field (ufrom, hfmt->byteorder, hfmt->totalsize,
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nkeynes@1265 | 294 | hfmt->exp_start, hfmt->exp_len);
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nkeynes@1265 | 295 | bot_exp = get_field (ufrom + 8, hfmt->byteorder, hfmt->totalsize,
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nkeynes@1265 | 296 | hfmt->exp_start, hfmt->exp_len);
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nkeynes@1265 | 297 |
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nkeynes@1265 | 298 | if ((unsigned long) top_exp == hfmt->exp_nan)
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nkeynes@1265 | 299 | top_nan = mant_bits_set (hfmt, ufrom);
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nkeynes@1265 | 300 |
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nkeynes@1265 | 301 | /* A NaN is valid with any low part. */
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nkeynes@1265 | 302 | if (top_nan)
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nkeynes@1265 | 303 | return 1;
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nkeynes@1265 | 304 |
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nkeynes@1265 | 305 | /* An infinity, zero or denormal requires low part 0 (positive or
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nkeynes@1265 | 306 | negative). */
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nkeynes@1265 | 307 | if ((unsigned long) top_exp == hfmt->exp_nan || top_exp == 0)
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nkeynes@1265 | 308 | {
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nkeynes@1265 | 309 | if (bot_exp != 0)
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nkeynes@1265 | 310 | return 0;
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nkeynes@1265 | 311 |
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nkeynes@1265 | 312 | return !mant_bits_set (hfmt, ufrom + 8);
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nkeynes@1265 | 313 | }
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nkeynes@1265 | 314 |
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nkeynes@1265 | 315 | /* The top part is now a finite normal value. The long double value
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nkeynes@1265 | 316 | is the sum of the two parts, and the top part must equal the
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nkeynes@1265 | 317 | result of rounding the long double value to nearest double. Thus
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nkeynes@1265 | 318 | the bottom part must be <= 0.5ulp of the top part in absolute
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nkeynes@1265 | 319 | value, and if it is < 0.5ulp then the long double is definitely
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nkeynes@1265 | 320 | valid. */
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nkeynes@1265 | 321 | if (bot_exp < top_exp - 53)
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nkeynes@1265 | 322 | return 1;
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nkeynes@1265 | 323 | if (bot_exp > top_exp - 53 && bot_exp != 0)
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nkeynes@1265 | 324 | return 0;
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nkeynes@1265 | 325 | if (bot_exp == 0)
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nkeynes@1265 | 326 | {
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nkeynes@1265 | 327 | /* The bottom part is 0 or denormal. Determine which, and if
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nkeynes@1265 | 328 | denormal the first two set bits. */
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nkeynes@1265 | 329 | int first_bit = -1, second_bit = -1, cur_bit;
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nkeynes@1265 | 330 | for (cur_bit = 0; (unsigned int) cur_bit < hfmt->man_len; cur_bit++)
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nkeynes@1265 | 331 | if (get_field (ufrom + 8, hfmt->byteorder, hfmt->totalsize,
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nkeynes@1265 | 332 | hfmt->man_start + cur_bit, 1))
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nkeynes@1265 | 333 | {
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nkeynes@1265 | 334 | if (first_bit == -1)
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nkeynes@1265 | 335 | first_bit = cur_bit;
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nkeynes@1265 | 336 | else
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nkeynes@1265 | 337 | {
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nkeynes@1265 | 338 | second_bit = cur_bit;
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nkeynes@1265 | 339 | break;
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nkeynes@1265 | 340 | }
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nkeynes@1265 | 341 | }
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nkeynes@1265 | 342 | /* Bottom part 0 is OK. */
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nkeynes@1265 | 343 | if (first_bit == -1)
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nkeynes@1265 | 344 | return 1;
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nkeynes@1265 | 345 | /* The real exponent of the bottom part is -first_bit. */
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nkeynes@1265 | 346 | if (-first_bit < top_exp - 53)
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nkeynes@1265 | 347 | return 1;
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nkeynes@1265 | 348 | if (-first_bit > top_exp - 53)
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nkeynes@1265 | 349 | return 0;
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nkeynes@1265 | 350 | /* The bottom part is at least 0.5ulp of the top part. For this
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nkeynes@1265 | 351 | to be OK, the bottom part must be exactly 0.5ulp (i.e. no
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nkeynes@1265 | 352 | more bits set) and the top part must have last bit 0. */
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nkeynes@1265 | 353 | if (second_bit != -1)
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nkeynes@1265 | 354 | return 0;
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nkeynes@1265 | 355 | return !get_field (ufrom, hfmt->byteorder, hfmt->totalsize,
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nkeynes@1265 | 356 | hfmt->man_start + hfmt->man_len - 1, 1);
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nkeynes@1265 | 357 | }
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nkeynes@1265 | 358 | else
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nkeynes@1265 | 359 | {
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nkeynes@1265 | 360 | /* The bottom part is at least 0.5ulp of the top part. For this
|
nkeynes@1265 | 361 | to be OK, it must be exactly 0.5ulp (i.e. no explicit bits
|
nkeynes@1265 | 362 | set) and the top part must have last bit 0. */
|
nkeynes@1265 | 363 | if (get_field (ufrom, hfmt->byteorder, hfmt->totalsize,
|
nkeynes@1265 | 364 | hfmt->man_start + hfmt->man_len - 1, 1))
|
nkeynes@1265 | 365 | return 0;
|
nkeynes@1265 | 366 | return !mant_bits_set (hfmt, ufrom + 8);
|
nkeynes@1265 | 367 | }
|
nkeynes@1265 | 368 | }
|
nkeynes@1265 | 369 |
|
nkeynes@1265 | 370 | const struct floatformat floatformat_ibm_long_double =
|
nkeynes@1265 | 371 | {
|
nkeynes@1265 | 372 | floatformat_big, 128, 0, 1, 11, 1023, 2047, 12, 52,
|
nkeynes@1265 | 373 | floatformat_intbit_no,
|
nkeynes@1265 | 374 | "floatformat_ibm_long_double",
|
nkeynes@1265 | 375 | floatformat_ibm_long_double_is_valid,
|
nkeynes@1265 | 376 | &floatformat_ieee_double_big
|
nkeynes@1265 | 377 | };
|
nkeynes@1265 | 378 |
|
nkeynes@1265 | 379 |
|
nkeynes@1265 | 380 | #ifndef min
|
nkeynes@1265 | 381 | #define min(a, b) ((a) < (b) ? (a) : (b))
|
nkeynes@1265 | 382 | #endif
|
nkeynes@1265 | 383 |
|
nkeynes@1265 | 384 | /* Return 1 if any bits are explicitly set in the mantissa of UFROM,
|
nkeynes@1265 | 385 | format FMT, 0 otherwise. */
|
nkeynes@1265 | 386 | static int
|
nkeynes@1265 | 387 | mant_bits_set (const struct floatformat *fmt, const unsigned char *ufrom)
|
nkeynes@1265 | 388 | {
|
nkeynes@1265 | 389 | unsigned int mant_bits, mant_off;
|
nkeynes@1265 | 390 | int mant_bits_left;
|
nkeynes@1265 | 391 |
|
nkeynes@1265 | 392 | mant_off = fmt->man_start;
|
nkeynes@1265 | 393 | mant_bits_left = fmt->man_len;
|
nkeynes@1265 | 394 | while (mant_bits_left > 0)
|
nkeynes@1265 | 395 | {
|
nkeynes@1265 | 396 | mant_bits = min (mant_bits_left, 32);
|
nkeynes@1265 | 397 |
|
nkeynes@1265 | 398 | if (get_field (ufrom, fmt->byteorder, fmt->totalsize,
|
nkeynes@1265 | 399 | mant_off, mant_bits) != 0)
|
nkeynes@1265 | 400 | return 1;
|
nkeynes@1265 | 401 |
|
nkeynes@1265 | 402 | mant_off += mant_bits;
|
nkeynes@1265 | 403 | mant_bits_left -= mant_bits;
|
nkeynes@1265 | 404 | }
|
nkeynes@1265 | 405 | return 0;
|
nkeynes@1265 | 406 | }
|
nkeynes@1265 | 407 |
|
nkeynes@1265 | 408 | /* Extract a field which starts at START and is LEN bits long. DATA and
|
nkeynes@1265 | 409 | TOTAL_LEN are the thing we are extracting it from, in byteorder ORDER. */
|
nkeynes@1265 | 410 | static unsigned long
|
nkeynes@1265 | 411 | get_field (const unsigned char *data, enum floatformat_byteorders order,
|
nkeynes@1265 | 412 | unsigned int total_len, unsigned int start, unsigned int len)
|
nkeynes@1265 | 413 | {
|
nkeynes@1265 | 414 | unsigned long result = 0;
|
nkeynes@1265 | 415 | unsigned int cur_byte;
|
nkeynes@1265 | 416 | int lo_bit, hi_bit, cur_bitshift = 0;
|
nkeynes@1265 | 417 | int nextbyte = (order == floatformat_little) ? 1 : -1;
|
nkeynes@1265 | 418 |
|
nkeynes@1265 | 419 | /* Start is in big-endian bit order! Fix that first. */
|
nkeynes@1265 | 420 | start = total_len - (start + len);
|
nkeynes@1265 | 421 |
|
nkeynes@1265 | 422 | /* Start at the least significant part of the field. */
|
nkeynes@1265 | 423 | if (order == floatformat_little)
|
nkeynes@1265 | 424 | cur_byte = start / FLOATFORMAT_CHAR_BIT;
|
nkeynes@1265 | 425 | else
|
nkeynes@1265 | 426 | cur_byte = (total_len - start - 1) / FLOATFORMAT_CHAR_BIT;
|
nkeynes@1265 | 427 |
|
nkeynes@1265 | 428 | lo_bit = start % FLOATFORMAT_CHAR_BIT;
|
nkeynes@1265 | 429 | hi_bit = min (lo_bit + len, FLOATFORMAT_CHAR_BIT);
|
nkeynes@1265 | 430 |
|
nkeynes@1265 | 431 | do
|
nkeynes@1265 | 432 | {
|
nkeynes@1265 | 433 | unsigned int shifted = *(data + cur_byte) >> lo_bit;
|
nkeynes@1265 | 434 | unsigned int bits = hi_bit - lo_bit;
|
nkeynes@1265 | 435 | unsigned int mask = (1 << bits) - 1;
|
nkeynes@1265 | 436 | result |= (shifted & mask) << cur_bitshift;
|
nkeynes@1265 | 437 | len -= bits;
|
nkeynes@1265 | 438 | cur_bitshift += bits;
|
nkeynes@1265 | 439 | cur_byte += nextbyte;
|
nkeynes@1265 | 440 | lo_bit = 0;
|
nkeynes@1265 | 441 | hi_bit = min (len, FLOATFORMAT_CHAR_BIT);
|
nkeynes@1265 | 442 | }
|
nkeynes@1265 | 443 | while (len != 0);
|
nkeynes@1265 | 444 |
|
nkeynes@1265 | 445 | return result;
|
nkeynes@1265 | 446 | }
|
nkeynes@1265 | 447 |
|
nkeynes@1265 | 448 | /* Convert from FMT to a double.
|
nkeynes@1265 | 449 | FROM is the address of the extended float.
|
nkeynes@1265 | 450 | Store the double in *TO. */
|
nkeynes@1265 | 451 |
|
nkeynes@1265 | 452 | void
|
nkeynes@1265 | 453 | floatformat_to_double (const struct floatformat *fmt,
|
nkeynes@1265 | 454 | const void *from, double *to)
|
nkeynes@1265 | 455 | {
|
nkeynes@1265 | 456 | const unsigned char *ufrom = (const unsigned char *) from;
|
nkeynes@1265 | 457 | double dto;
|
nkeynes@1265 | 458 | long exponent;
|
nkeynes@1265 | 459 | unsigned long mant;
|
nkeynes@1265 | 460 | unsigned int mant_bits, mant_off;
|
nkeynes@1265 | 461 | int mant_bits_left;
|
nkeynes@1265 | 462 | int special_exponent; /* It's a NaN, denorm or zero */
|
nkeynes@1265 | 463 |
|
nkeynes@1265 | 464 | /* Split values are not handled specially, since the top half has
|
nkeynes@1265 | 465 | the correctly rounded double value (in the only supported case of
|
nkeynes@1265 | 466 | split values). */
|
nkeynes@1265 | 467 |
|
nkeynes@1265 | 468 | exponent = get_field (ufrom, fmt->byteorder, fmt->totalsize,
|
nkeynes@1265 | 469 | fmt->exp_start, fmt->exp_len);
|
nkeynes@1265 | 470 |
|
nkeynes@1265 | 471 | /* If the exponent indicates a NaN, we don't have information to
|
nkeynes@1265 | 472 | decide what to do. So we handle it like IEEE, except that we
|
nkeynes@1265 | 473 | don't try to preserve the type of NaN. FIXME. */
|
nkeynes@1265 | 474 | if ((unsigned long) exponent == fmt->exp_nan)
|
nkeynes@1265 | 475 | {
|
nkeynes@1265 | 476 | int nan = mant_bits_set (fmt, ufrom);
|
nkeynes@1265 | 477 |
|
nkeynes@1265 | 478 | /* On certain systems (such as GNU/Linux), the use of the
|
nkeynes@1265 | 479 | INFINITY macro below may generate a warning that can not be
|
nkeynes@1265 | 480 | silenced due to a bug in GCC (PR preprocessor/11931). The
|
nkeynes@1265 | 481 | preprocessor fails to recognise the __extension__ keyword in
|
nkeynes@1265 | 482 | conjunction with the GNU/C99 extension for hexadecimal
|
nkeynes@1265 | 483 | floating point constants and will issue a warning when
|
nkeynes@1265 | 484 | compiling with -pedantic. */
|
nkeynes@1265 | 485 | if (nan)
|
nkeynes@1265 | 486 | dto = NAN;
|
nkeynes@1265 | 487 | else
|
nkeynes@1265 | 488 | dto = INFINITY;
|
nkeynes@1265 | 489 |
|
nkeynes@1265 | 490 | if (get_field (ufrom, fmt->byteorder, fmt->totalsize, fmt->sign_start, 1))
|
nkeynes@1265 | 491 | dto = -dto;
|
nkeynes@1265 | 492 |
|
nkeynes@1265 | 493 | *to = dto;
|
nkeynes@1265 | 494 |
|
nkeynes@1265 | 495 | return;
|
nkeynes@1265 | 496 | }
|
nkeynes@1265 | 497 |
|
nkeynes@1265 | 498 | mant_bits_left = fmt->man_len;
|
nkeynes@1265 | 499 | mant_off = fmt->man_start;
|
nkeynes@1265 | 500 | dto = 0.0;
|
nkeynes@1265 | 501 |
|
nkeynes@1265 | 502 | special_exponent = exponent == 0 || (unsigned long) exponent == fmt->exp_nan;
|
nkeynes@1265 | 503 |
|
nkeynes@1265 | 504 | /* Don't bias zero's, denorms or NaNs. */
|
nkeynes@1265 | 505 | if (!special_exponent)
|
nkeynes@1265 | 506 | exponent -= fmt->exp_bias;
|
nkeynes@1265 | 507 |
|
nkeynes@1265 | 508 | /* Build the result algebraically. Might go infinite, underflow, etc;
|
nkeynes@1265 | 509 | who cares. */
|
nkeynes@1265 | 510 |
|
nkeynes@1265 | 511 | /* If this format uses a hidden bit, explicitly add it in now. Otherwise,
|
nkeynes@1265 | 512 | increment the exponent by one to account for the integer bit. */
|
nkeynes@1265 | 513 |
|
nkeynes@1265 | 514 | if (!special_exponent)
|
nkeynes@1265 | 515 | {
|
nkeynes@1265 | 516 | if (fmt->intbit == floatformat_intbit_no)
|
nkeynes@1265 | 517 | dto = ldexp (1.0, exponent);
|
nkeynes@1265 | 518 | else
|
nkeynes@1265 | 519 | exponent++;
|
nkeynes@1265 | 520 | }
|
nkeynes@1265 | 521 |
|
nkeynes@1265 | 522 | while (mant_bits_left > 0)
|
nkeynes@1265 | 523 | {
|
nkeynes@1265 | 524 | mant_bits = min (mant_bits_left, 32);
|
nkeynes@1265 | 525 |
|
nkeynes@1265 | 526 | mant = get_field (ufrom, fmt->byteorder, fmt->totalsize,
|
nkeynes@1265 | 527 | mant_off, mant_bits);
|
nkeynes@1265 | 528 |
|
nkeynes@1265 | 529 | /* Handle denormalized numbers. FIXME: What should we do for
|
nkeynes@1265 | 530 | non-IEEE formats? */
|
nkeynes@1265 | 531 | if (special_exponent && exponent == 0 && mant != 0)
|
nkeynes@1265 | 532 | dto += ldexp ((double)mant,
|
nkeynes@1265 | 533 | (- fmt->exp_bias
|
nkeynes@1265 | 534 | - mant_bits
|
nkeynes@1265 | 535 | - (mant_off - fmt->man_start)
|
nkeynes@1265 | 536 | + 1));
|
nkeynes@1265 | 537 | else
|
nkeynes@1265 | 538 | dto += ldexp ((double)mant, exponent - mant_bits);
|
nkeynes@1265 | 539 | if (exponent != 0)
|
nkeynes@1265 | 540 | exponent -= mant_bits;
|
nkeynes@1265 | 541 | mant_off += mant_bits;
|
nkeynes@1265 | 542 | mant_bits_left -= mant_bits;
|
nkeynes@1265 | 543 | }
|
nkeynes@1265 | 544 |
|
nkeynes@1265 | 545 | /* Negate it if negative. */
|
nkeynes@1265 | 546 | if (get_field (ufrom, fmt->byteorder, fmt->totalsize, fmt->sign_start, 1))
|
nkeynes@1265 | 547 | dto = -dto;
|
nkeynes@1265 | 548 | *to = dto;
|
nkeynes@1265 | 549 | }
|
nkeynes@1265 | 550 |
|
nkeynes@1265 | 551 | static void put_field (unsigned char *, enum floatformat_byteorders,
|
nkeynes@1265 | 552 | unsigned int,
|
nkeynes@1265 | 553 | unsigned int,
|
nkeynes@1265 | 554 | unsigned int,
|
nkeynes@1265 | 555 | unsigned long);
|
nkeynes@1265 | 556 |
|
nkeynes@1265 | 557 | /* Set a field which starts at START and is LEN bits long. DATA and
|
nkeynes@1265 | 558 | TOTAL_LEN are the thing we are extracting it from, in byteorder ORDER. */
|
nkeynes@1265 | 559 | static void
|
nkeynes@1265 | 560 | put_field (unsigned char *data, enum floatformat_byteorders order,
|
nkeynes@1265 | 561 | unsigned int total_len, unsigned int start, unsigned int len,
|
nkeynes@1265 | 562 | unsigned long stuff_to_put)
|
nkeynes@1265 | 563 | {
|
nkeynes@1265 | 564 | unsigned int cur_byte;
|
nkeynes@1265 | 565 | int lo_bit, hi_bit;
|
nkeynes@1265 | 566 | int nextbyte = (order == floatformat_little) ? 1 : -1;
|
nkeynes@1265 | 567 |
|
nkeynes@1265 | 568 | /* Start is in big-endian bit order! Fix that first. */
|
nkeynes@1265 | 569 | start = total_len - (start + len);
|
nkeynes@1265 | 570 |
|
nkeynes@1265 | 571 | /* Start at the least significant part of the field. */
|
nkeynes@1265 | 572 | if (order == floatformat_little)
|
nkeynes@1265 | 573 | cur_byte = start / FLOATFORMAT_CHAR_BIT;
|
nkeynes@1265 | 574 | else
|
nkeynes@1265 | 575 | cur_byte = (total_len - start - 1) / FLOATFORMAT_CHAR_BIT;
|
nkeynes@1265 | 576 |
|
nkeynes@1265 | 577 | lo_bit = start % FLOATFORMAT_CHAR_BIT;
|
nkeynes@1265 | 578 | hi_bit = min (lo_bit + len, FLOATFORMAT_CHAR_BIT);
|
nkeynes@1265 | 579 |
|
nkeynes@1265 | 580 | do
|
nkeynes@1265 | 581 | {
|
nkeynes@1265 | 582 | unsigned char *byte_ptr = data + cur_byte;
|
nkeynes@1265 | 583 | unsigned int bits = hi_bit - lo_bit;
|
nkeynes@1265 | 584 | unsigned int mask = ((1 << bits) - 1) << lo_bit;
|
nkeynes@1265 | 585 | *byte_ptr = (*byte_ptr & ~mask) | ((stuff_to_put << lo_bit) & mask);
|
nkeynes@1265 | 586 | stuff_to_put >>= bits;
|
nkeynes@1265 | 587 | len -= bits;
|
nkeynes@1265 | 588 | cur_byte += nextbyte;
|
nkeynes@1265 | 589 | lo_bit = 0;
|
nkeynes@1265 | 590 | hi_bit = min (len, FLOATFORMAT_CHAR_BIT);
|
nkeynes@1265 | 591 | }
|
nkeynes@1265 | 592 | while (len != 0);
|
nkeynes@1265 | 593 | }
|
nkeynes@1265 | 594 |
|
nkeynes@1265 | 595 | /* The converse: convert the double *FROM to an extended float
|
nkeynes@1265 | 596 | and store where TO points. Neither FROM nor TO have any alignment
|
nkeynes@1265 | 597 | restrictions. */
|
nkeynes@1265 | 598 |
|
nkeynes@1265 | 599 | void
|
nkeynes@1265 | 600 | floatformat_from_double (const struct floatformat *fmt,
|
nkeynes@1265 | 601 | const double *from, void *to)
|
nkeynes@1265 | 602 | {
|
nkeynes@1265 | 603 | double dfrom;
|
nkeynes@1265 | 604 | int exponent;
|
nkeynes@1265 | 605 | double mant;
|
nkeynes@1265 | 606 | unsigned int mant_bits, mant_off;
|
nkeynes@1265 | 607 | int mant_bits_left;
|
nkeynes@1265 | 608 | unsigned char *uto = (unsigned char *) to;
|
nkeynes@1265 | 609 |
|
nkeynes@1265 | 610 | dfrom = *from;
|
nkeynes@1265 | 611 | memset (uto, 0, fmt->totalsize / FLOATFORMAT_CHAR_BIT);
|
nkeynes@1265 | 612 |
|
nkeynes@1265 | 613 | /* Split values are not handled specially, since a bottom half of
|
nkeynes@1265 | 614 | zero is correct for any value representable as double (in the
|
nkeynes@1265 | 615 | only supported case of split values). */
|
nkeynes@1265 | 616 |
|
nkeynes@1265 | 617 | /* If negative, set the sign bit. */
|
nkeynes@1265 | 618 | if (dfrom < 0)
|
nkeynes@1265 | 619 | {
|
nkeynes@1265 | 620 | put_field (uto, fmt->byteorder, fmt->totalsize, fmt->sign_start, 1, 1);
|
nkeynes@1265 | 621 | dfrom = -dfrom;
|
nkeynes@1265 | 622 | }
|
nkeynes@1265 | 623 |
|
nkeynes@1265 | 624 | if (dfrom == 0)
|
nkeynes@1265 | 625 | {
|
nkeynes@1265 | 626 | /* 0.0. */
|
nkeynes@1265 | 627 | return;
|
nkeynes@1265 | 628 | }
|
nkeynes@1265 | 629 |
|
nkeynes@1265 | 630 | if (dfrom != dfrom)
|
nkeynes@1265 | 631 | {
|
nkeynes@1265 | 632 | /* NaN. */
|
nkeynes@1265 | 633 | put_field (uto, fmt->byteorder, fmt->totalsize, fmt->exp_start,
|
nkeynes@1265 | 634 | fmt->exp_len, fmt->exp_nan);
|
nkeynes@1265 | 635 | /* Be sure it's not infinity, but NaN value is irrelevant. */
|
nkeynes@1265 | 636 | put_field (uto, fmt->byteorder, fmt->totalsize, fmt->man_start,
|
nkeynes@1265 | 637 | 32, 1);
|
nkeynes@1265 | 638 | return;
|
nkeynes@1265 | 639 | }
|
nkeynes@1265 | 640 |
|
nkeynes@1265 | 641 | if (dfrom + dfrom == dfrom)
|
nkeynes@1265 | 642 | {
|
nkeynes@1265 | 643 | /* This can only happen for an infinite value (or zero, which we
|
nkeynes@1265 | 644 | already handled above). */
|
nkeynes@1265 | 645 | put_field (uto, fmt->byteorder, fmt->totalsize, fmt->exp_start,
|
nkeynes@1265 | 646 | fmt->exp_len, fmt->exp_nan);
|
nkeynes@1265 | 647 | return;
|
nkeynes@1265 | 648 | }
|
nkeynes@1265 | 649 |
|
nkeynes@1265 | 650 | mant = frexp (dfrom, &exponent);
|
nkeynes@1265 | 651 | if (exponent + fmt->exp_bias - 1 > 0)
|
nkeynes@1265 | 652 | put_field (uto, fmt->byteorder, fmt->totalsize, fmt->exp_start,
|
nkeynes@1265 | 653 | fmt->exp_len, exponent + fmt->exp_bias - 1);
|
nkeynes@1265 | 654 | else
|
nkeynes@1265 | 655 | {
|
nkeynes@1265 | 656 | /* Handle a denormalized number. FIXME: What should we do for
|
nkeynes@1265 | 657 | non-IEEE formats? */
|
nkeynes@1265 | 658 | put_field (uto, fmt->byteorder, fmt->totalsize, fmt->exp_start,
|
nkeynes@1265 | 659 | fmt->exp_len, 0);
|
nkeynes@1265 | 660 | mant = ldexp (mant, exponent + fmt->exp_bias - 1);
|
nkeynes@1265 | 661 | }
|
nkeynes@1265 | 662 |
|
nkeynes@1265 | 663 | mant_bits_left = fmt->man_len;
|
nkeynes@1265 | 664 | mant_off = fmt->man_start;
|
nkeynes@1265 | 665 | while (mant_bits_left > 0)
|
nkeynes@1265 | 666 | {
|
nkeynes@1265 | 667 | unsigned long mant_long;
|
nkeynes@1265 | 668 | mant_bits = mant_bits_left < 32 ? mant_bits_left : 32;
|
nkeynes@1265 | 669 |
|
nkeynes@1265 | 670 | mant *= 4294967296.0;
|
nkeynes@1265 | 671 | mant_long = (unsigned long)mant;
|
nkeynes@1265 | 672 | mant -= mant_long;
|
nkeynes@1265 | 673 |
|
nkeynes@1265 | 674 | /* If the integer bit is implicit, and we are not creating a
|
nkeynes@1265 | 675 | denormalized number, then we need to discard it. */
|
nkeynes@1265 | 676 | if ((unsigned int) mant_bits_left == fmt->man_len
|
nkeynes@1265 | 677 | && fmt->intbit == floatformat_intbit_no
|
nkeynes@1265 | 678 | && exponent + fmt->exp_bias - 1 > 0)
|
nkeynes@1265 | 679 | {
|
nkeynes@1265 | 680 | mant_long &= 0x7fffffff;
|
nkeynes@1265 | 681 | mant_bits -= 1;
|
nkeynes@1265 | 682 | }
|
nkeynes@1265 | 683 | else if (mant_bits < 32)
|
nkeynes@1265 | 684 | {
|
nkeynes@1265 | 685 | /* The bits we want are in the most significant MANT_BITS bits of
|
nkeynes@1265 | 686 | mant_long. Move them to the least significant. */
|
nkeynes@1265 | 687 | mant_long >>= 32 - mant_bits;
|
nkeynes@1265 | 688 | }
|
nkeynes@1265 | 689 |
|
nkeynes@1265 | 690 | put_field (uto, fmt->byteorder, fmt->totalsize,
|
nkeynes@1265 | 691 | mant_off, mant_bits, mant_long);
|
nkeynes@1265 | 692 | mant_off += mant_bits;
|
nkeynes@1265 | 693 | mant_bits_left -= mant_bits;
|
nkeynes@1265 | 694 | }
|
nkeynes@1265 | 695 | }
|
nkeynes@1265 | 696 |
|
nkeynes@1265 | 697 | /* Return non-zero iff the data at FROM is a valid number in format FMT. */
|
nkeynes@1265 | 698 |
|
nkeynes@1265 | 699 | int
|
nkeynes@1265 | 700 | floatformat_is_valid (const struct floatformat *fmt, const void *from)
|
nkeynes@1265 | 701 | {
|
nkeynes@1265 | 702 | return fmt->is_valid (fmt, from);
|
nkeynes@1265 | 703 | }
|
nkeynes@1265 | 704 |
|
nkeynes@1265 | 705 |
|
nkeynes@1265 | 706 | #ifdef IEEE_DEBUG
|
nkeynes@1265 | 707 |
|
nkeynes@1265 | 708 | #include <stdio.h>
|
nkeynes@1265 | 709 |
|
nkeynes@1265 | 710 | /* This is to be run on a host which uses IEEE floating point. */
|
nkeynes@1265 | 711 |
|
nkeynes@1265 | 712 | void
|
nkeynes@1265 | 713 | ieee_test (double n)
|
nkeynes@1265 | 714 | {
|
nkeynes@1265 | 715 | double result;
|
nkeynes@1265 | 716 |
|
nkeynes@1265 | 717 | floatformat_to_double (&floatformat_ieee_double_little, &n, &result);
|
nkeynes@1265 | 718 | if ((n != result && (! isnan (n) || ! isnan (result)))
|
nkeynes@1265 | 719 | || (n < 0 && result >= 0)
|
nkeynes@1265 | 720 | || (n >= 0 && result < 0))
|
nkeynes@1265 | 721 | printf ("Differ(to): %.20g -> %.20g\n", n, result);
|
nkeynes@1265 | 722 |
|
nkeynes@1265 | 723 | floatformat_from_double (&floatformat_ieee_double_little, &n, &result);
|
nkeynes@1265 | 724 | if ((n != result && (! isnan (n) || ! isnan (result)))
|
nkeynes@1265 | 725 | || (n < 0 && result >= 0)
|
nkeynes@1265 | 726 | || (n >= 0 && result < 0))
|
nkeynes@1265 | 727 | printf ("Differ(from): %.20g -> %.20g\n", n, result);
|
nkeynes@1265 | 728 |
|
nkeynes@1265 | 729 | #if 0
|
nkeynes@1265 | 730 | {
|
nkeynes@1265 | 731 | char exten[16];
|
nkeynes@1265 | 732 |
|
nkeynes@1265 | 733 | floatformat_from_double (&floatformat_m68881_ext, &n, exten);
|
nkeynes@1265 | 734 | floatformat_to_double (&floatformat_m68881_ext, exten, &result);
|
nkeynes@1265 | 735 | if (n != result)
|
nkeynes@1265 | 736 | printf ("Differ(to+from): %.20g -> %.20g\n", n, result);
|
nkeynes@1265 | 737 | }
|
nkeynes@1265 | 738 | #endif
|
nkeynes@1265 | 739 |
|
nkeynes@1265 | 740 | #if IEEE_DEBUG > 1
|
nkeynes@1265 | 741 | /* This is to be run on a host which uses 68881 format. */
|
nkeynes@1265 | 742 | {
|
nkeynes@1265 | 743 | long double ex = *(long double *)exten;
|
nkeynes@1265 | 744 | if (ex != n)
|
nkeynes@1265 | 745 | printf ("Differ(from vs. extended): %.20g\n", n);
|
nkeynes@1265 | 746 | }
|
nkeynes@1265 | 747 | #endif
|
nkeynes@1265 | 748 | }
|
nkeynes@1265 | 749 |
|
nkeynes@1265 | 750 | int
|
nkeynes@1265 | 751 | main (void)
|
nkeynes@1265 | 752 | {
|
nkeynes@1265 | 753 | ieee_test (0.0);
|
nkeynes@1265 | 754 | ieee_test (0.5);
|
nkeynes@1265 | 755 | ieee_test (256.0);
|
nkeynes@1265 | 756 | ieee_test (0.12345);
|
nkeynes@1265 | 757 | ieee_test (234235.78907234);
|
nkeynes@1265 | 758 | ieee_test (-512.0);
|
nkeynes@1265 | 759 | ieee_test (-0.004321);
|
nkeynes@1265 | 760 | ieee_test (1.2E-70);
|
nkeynes@1265 | 761 | ieee_test (1.2E-316);
|
nkeynes@1265 | 762 | ieee_test (4.9406564584124654E-324);
|
nkeynes@1265 | 763 | ieee_test (- 4.9406564584124654E-324);
|
nkeynes@1265 | 764 | ieee_test (- 0.0);
|
nkeynes@1265 | 765 | ieee_test (- INFINITY);
|
nkeynes@1265 | 766 | ieee_test (- NAN);
|
nkeynes@1265 | 767 | ieee_test (INFINITY);
|
nkeynes@1265 | 768 | ieee_test (NAN);
|
nkeynes@1265 | 769 | return 0;
|
nkeynes@1265 | 770 | }
|
nkeynes@1265 | 771 | #endif
|