1 /* IEEE floating point support declarations, for GDB, the GNU Debugger. 2 Copyright 1991, 1994, 1995, 1997, 2000, 2003 Free Software Foundation, Inc. 3 4 This file is part of GDB. 5 6 This program is free software; you can redistribute it and/or modify 7 it under the terms of the GNU General Public License as published by 8 the Free Software Foundation; either version 2 of the License, or 9 (at your option) any later version. 10 11 This program is distributed in the hope that it will be useful, 12 but WITHOUT ANY WARRANTY; without even the implied warranty of 13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 GNU General Public License for more details. 15 16 You should have received a copy of the GNU General Public License 17 along with this program; if not, write to the Free Software 18 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ 19 20 #if !defined (FLOATFORMAT_H) 21 #define FLOATFORMAT_H 1 22 23 #include "ansidecl.h" 24 25 /* A floatformat consists of a sign bit, an exponent and a mantissa. Once the 26 bytes are concatenated according to the byteorder flag, then each of those 27 fields is contiguous. We number the bits with 0 being the most significant 28 (i.e. BITS_BIG_ENDIAN type numbering), and specify which bits each field 29 contains with the *_start and *_len fields. */ 30 31 /* What is the order of the bytes. */ 32 33 enum floatformat_byteorders { 34 35 /* Standard little endian byte order. 36 EX: 1.2345678e10 => 00 00 80 c5 e0 fe 06 42 */ 37 38 floatformat_little, 39 40 /* Standard big endian byte order. 41 EX: 1.2345678e10 => 42 06 fe e0 c5 80 00 00 */ 42 43 floatformat_big, 44 45 /* Little endian byte order but big endian word order. 46 EX: 1.2345678e10 => e0 fe 06 42 00 00 80 c5 */ 47 48 floatformat_littlebyte_bigword 49 50 }; 51 52 enum floatformat_intbit { floatformat_intbit_yes, floatformat_intbit_no }; 53 54 struct floatformat 55 { 56 enum floatformat_byteorders byteorder; 57 unsigned int totalsize; /* Total size of number in bits */ 58 59 /* Sign bit is always one bit long. 1 means negative, 0 means positive. */ 60 unsigned int sign_start; 61 62 unsigned int exp_start; 63 unsigned int exp_len; 64 /* Bias added to a "true" exponent to form the biased exponent. It 65 is intentionally signed as, otherwize, -exp_bias can turn into a 66 very large number (e.g., given the exp_bias of 0x3fff and a 64 67 bit long, the equation (long)(1 - exp_bias) evaluates to 68 4294950914) instead of -16382). */ 69 int exp_bias; 70 /* Exponent value which indicates NaN. This is the actual value stored in 71 the float, not adjusted by the exp_bias. This usually consists of all 72 one bits. */ 73 unsigned int exp_nan; 74 75 unsigned int man_start; 76 unsigned int man_len; 77 78 /* Is the integer bit explicit or implicit? */ 79 enum floatformat_intbit intbit; 80 81 /* Internal name for debugging. */ 82 const char *name; 83 84 /* Validator method. */ 85 int (*is_valid) PARAMS ((const struct floatformat *fmt, const char *from)); 86 }; 87 88 /* floatformats for IEEE single and double, big and little endian. */ 89 90 extern const struct floatformat floatformat_ieee_single_big; 91 extern const struct floatformat floatformat_ieee_single_little; 92 extern const struct floatformat floatformat_ieee_double_big; 93 extern const struct floatformat floatformat_ieee_double_little; 94 95 /* floatformat for ARM IEEE double, little endian bytes and big endian words */ 96 97 extern const struct floatformat floatformat_ieee_double_littlebyte_bigword; 98 99 /* floatformats for various extendeds. */ 100 101 extern const struct floatformat floatformat_i387_ext; 102 extern const struct floatformat floatformat_m68881_ext; 103 extern const struct floatformat floatformat_i960_ext; 104 extern const struct floatformat floatformat_m88110_ext; 105 extern const struct floatformat floatformat_m88110_harris_ext; 106 extern const struct floatformat floatformat_arm_ext_big; 107 extern const struct floatformat floatformat_arm_ext_littlebyte_bigword; 108 /* IA-64 Floating Point register spilt into memory. */ 109 extern const struct floatformat floatformat_ia64_spill_big; 110 extern const struct floatformat floatformat_ia64_spill_little; 111 extern const struct floatformat floatformat_ia64_quad_big; 112 extern const struct floatformat floatformat_ia64_quad_little; 113 114 /* Convert from FMT to a double. 115 FROM is the address of the extended float. 116 Store the double in *TO. */ 117 118 extern void 119 floatformat_to_double PARAMS ((const struct floatformat *, const char *, double *)); 120 121 /* The converse: convert the double *FROM to FMT 122 and store where TO points. */ 123 124 extern void 125 floatformat_from_double PARAMS ((const struct floatformat *, 126 const double *, char *)); 127 128 /* Return non-zero iff the data at FROM is a valid number in format FMT. */ 129 130 extern int 131 floatformat_is_valid PARAMS ((const struct floatformat *fmt, const char *from)); 132 133 #endif /* defined (FLOATFORMAT_H) */ 134