1 2 /* 3 =============================================================================== 4 5 This C header file is part of the SoftFloat IEC/IEEE Floating-point 6 Arithmetic Package, Release 2. 7 8 Written by John R. Hauser. This work was made possible in part by the 9 International Computer Science Institute, located at Suite 600, 1947 Center 10 Street, Berkeley, California 94704. Funding was partially provided by the 11 National Science Foundation under grant MIP-9311980. The original version 12 of this code was written as part of a project to build a fixed-point vector 13 processor in collaboration with the University of California at Berkeley, 14 overseen by Profs. Nelson Morgan and John Wawrzynek. More information 15 is available through the Web page `http://HTTP.CS.Berkeley.EDU/~jhauser/ 16 arithmetic/softfloat.html'. 17 18 THIS SOFTWARE IS DISTRIBUTED AS IS, FOR FREE. Although reasonable effort 19 has been made to avoid it, THIS SOFTWARE MAY CONTAIN FAULTS THAT WILL AT 20 TIMES RESULT IN INCORRECT BEHAVIOR. USE OF THIS SOFTWARE IS RESTRICTED TO 21 PERSONS AND ORGANIZATIONS WHO CAN AND WILL TAKE FULL RESPONSIBILITY FOR ANY 22 AND ALL LOSSES, COSTS, OR OTHER PROBLEMS ARISING FROM ITS USE. 23 24 Derivative works are acceptable, even for commercial purposes, so long as 25 (1) they include prominent notice that the work is derivative, and (2) they 26 include prominent notice akin to these three paragraphs for those parts of 27 this code that are retained. 28 29 =============================================================================== 30 */ 31 32 #ifndef __SOFTFLOAT_H__ 33 #define __SOFTFLOAT_H__ 34 35 #include <linux/config.h> 36 37 /* 38 ------------------------------------------------------------------------------- 39 The macro `FLOATX80' must be defined to enable the extended double-precision 40 floating-point format `floatx80'. If this macro is not defined, the 41 `floatx80' type will not be defined, and none of the functions that either 42 input or output the `floatx80' type will be defined. 43 ------------------------------------------------------------------------------- 44 */ 45 #ifdef CONFIG_FPE_NWFPE_XP 46 #define FLOATX80 47 #endif 48 49 /* 50 ------------------------------------------------------------------------------- 51 Software IEC/IEEE floating-point types. 52 ------------------------------------------------------------------------------- 53 */ 54 typedef unsigned long int float32; 55 typedef unsigned long long float64; 56 typedef struct { 57 unsigned short high; 58 unsigned long long low; 59 } floatx80; 60 61 /* 62 ------------------------------------------------------------------------------- 63 Software IEC/IEEE floating-point underflow tininess-detection mode. 64 ------------------------------------------------------------------------------- 65 */ 66 extern signed char float_detect_tininess; 67 enum { 68 float_tininess_after_rounding = 0, 69 float_tininess_before_rounding = 1 70 }; 71 72 /* 73 ------------------------------------------------------------------------------- 74 Software IEC/IEEE floating-point rounding mode. 75 ------------------------------------------------------------------------------- 76 */ 77 //extern int8 float_rounding_mode; 78 enum { 79 float_round_nearest_even = 0, 80 float_round_to_zero = 1, 81 float_round_down = 2, 82 float_round_up = 3 83 }; 84 85 /* 86 ------------------------------------------------------------------------------- 87 Software IEC/IEEE floating-point exception flags. 88 ------------------------------------------------------------------------------- 89 enum { 90 float_flag_inexact = 1, 91 float_flag_underflow = 2, 92 float_flag_overflow = 4, 93 float_flag_divbyzero = 8, 94 float_flag_invalid = 16 95 }; 96 97 ScottB: November 4, 1998 98 Changed the enumeration to match the bit order in the FPA11. 99 */ 100 101 enum { 102 float_flag_invalid = 1, 103 float_flag_divbyzero = 2, 104 float_flag_overflow = 4, 105 float_flag_underflow = 8, 106 float_flag_inexact = 16 107 }; 108 109 /* 110 ------------------------------------------------------------------------------- 111 Routine to raise any or all of the software IEC/IEEE floating-point 112 exception flags. 113 ------------------------------------------------------------------------------- 114 */ 115 void float_raise( signed char ); 116 117 /* 118 ------------------------------------------------------------------------------- 119 Software IEC/IEEE integer-to-floating-point conversion routines. 120 ------------------------------------------------------------------------------- 121 */ 122 float32 int32_to_float32( struct roundingData *, signed int ); 123 float64 int32_to_float64( signed int ); 124 #ifdef FLOATX80 125 floatx80 int32_to_floatx80( signed int ); 126 #endif 127 128 /* 129 ------------------------------------------------------------------------------- 130 Software IEC/IEEE single-precision conversion routines. 131 ------------------------------------------------------------------------------- 132 */ 133 signed int float32_to_int32( struct roundingData *, float32 ); 134 signed int float32_to_int32_round_to_zero( float32 ); 135 float64 float32_to_float64( float32 ); 136 #ifdef FLOATX80 137 floatx80 float32_to_floatx80( float32 ); 138 #endif 139 140 /* 141 ------------------------------------------------------------------------------- 142 Software IEC/IEEE single-precision operations. 143 ------------------------------------------------------------------------------- 144 */ 145 float32 float32_round_to_int( struct roundingData*, float32 ); 146 float32 float32_add( struct roundingData *, float32, float32 ); 147 float32 float32_sub( struct roundingData *, float32, float32 ); 148 float32 float32_mul( struct roundingData *, float32, float32 ); 149 float32 float32_div( struct roundingData *, float32, float32 ); 150 float32 float32_rem( struct roundingData *, float32, float32 ); 151 float32 float32_sqrt( struct roundingData*, float32 ); 152 char float32_eq( float32, float32 ); 153 char float32_le( float32, float32 ); 154 char float32_lt( float32, float32 ); 155 char float32_eq_signaling( float32, float32 ); 156 char float32_le_quiet( float32, float32 ); 157 char float32_lt_quiet( float32, float32 ); 158 char float32_is_signaling_nan( float32 ); 159 160 /* 161 ------------------------------------------------------------------------------- 162 Software IEC/IEEE double-precision conversion routines. 163 ------------------------------------------------------------------------------- 164 */ 165 signed int float64_to_int32( struct roundingData *, float64 ); 166 signed int float64_to_int32_round_to_zero( float64 ); 167 float32 float64_to_float32( struct roundingData *, float64 ); 168 #ifdef FLOATX80 169 floatx80 float64_to_floatx80( float64 ); 170 #endif 171 172 /* 173 ------------------------------------------------------------------------------- 174 Software IEC/IEEE double-precision operations. 175 ------------------------------------------------------------------------------- 176 */ 177 float64 float64_round_to_int( struct roundingData *, float64 ); 178 float64 float64_add( struct roundingData *, float64, float64 ); 179 float64 float64_sub( struct roundingData *, float64, float64 ); 180 float64 float64_mul( struct roundingData *, float64, float64 ); 181 float64 float64_div( struct roundingData *, float64, float64 ); 182 float64 float64_rem( struct roundingData *, float64, float64 ); 183 float64 float64_sqrt( struct roundingData *, float64 ); 184 char float64_eq( float64, float64 ); 185 char float64_le( float64, float64 ); 186 char float64_lt( float64, float64 ); 187 char float64_eq_signaling( float64, float64 ); 188 char float64_le_quiet( float64, float64 ); 189 char float64_lt_quiet( float64, float64 ); 190 char float64_is_signaling_nan( float64 ); 191 192 #ifdef FLOATX80 193 194 /* 195 ------------------------------------------------------------------------------- 196 Software IEC/IEEE extended double-precision conversion routines. 197 ------------------------------------------------------------------------------- 198 */ 199 signed int floatx80_to_int32( struct roundingData *, floatx80 ); 200 signed int floatx80_to_int32_round_to_zero( floatx80 ); 201 float32 floatx80_to_float32( struct roundingData *, floatx80 ); 202 float64 floatx80_to_float64( struct roundingData *, floatx80 ); 203 204 /* 205 ------------------------------------------------------------------------------- 206 Software IEC/IEEE extended double-precision operations. 207 ------------------------------------------------------------------------------- 208 */ 209 floatx80 floatx80_round_to_int( struct roundingData *, floatx80 ); 210 floatx80 floatx80_add( struct roundingData *, floatx80, floatx80 ); 211 floatx80 floatx80_sub( struct roundingData *, floatx80, floatx80 ); 212 floatx80 floatx80_mul( struct roundingData *, floatx80, floatx80 ); 213 floatx80 floatx80_div( struct roundingData *, floatx80, floatx80 ); 214 floatx80 floatx80_rem( struct roundingData *, floatx80, floatx80 ); 215 floatx80 floatx80_sqrt( struct roundingData *, floatx80 ); 216 char floatx80_eq( floatx80, floatx80 ); 217 char floatx80_le( floatx80, floatx80 ); 218 char floatx80_lt( floatx80, floatx80 ); 219 char floatx80_eq_signaling( floatx80, floatx80 ); 220 char floatx80_le_quiet( floatx80, floatx80 ); 221 char floatx80_lt_quiet( floatx80, floatx80 ); 222 char floatx80_is_signaling_nan( floatx80 ); 223 224 #endif 225 226 static inline flag extractFloat32Sign(float32 a) 227 { 228 return a >> 31; 229 } 230 231 static inline flag float32_eq_nocheck(float32 a, float32 b) 232 { 233 return (a == b) || ((bits32) ((a | b) << 1) == 0); 234 } 235 236 static inline flag float32_lt_nocheck(float32 a, float32 b) 237 { 238 flag aSign, bSign; 239 240 aSign = extractFloat32Sign(a); 241 bSign = extractFloat32Sign(b); 242 if (aSign != bSign) 243 return aSign && ((bits32) ((a | b) << 1) != 0); 244 return (a != b) && (aSign ^ (a < b)); 245 } 246 247 static inline flag extractFloat64Sign(float64 a) 248 { 249 return a >> 63; 250 } 251 252 static inline flag float64_eq_nocheck(float64 a, float64 b) 253 { 254 return (a == b) || ((bits64) ((a | b) << 1) == 0); 255 } 256 257 static inline flag float64_lt_nocheck(float64 a, float64 b) 258 { 259 flag aSign, bSign; 260 261 aSign = extractFloat64Sign(a); 262 bSign = extractFloat64Sign(b); 263 if (aSign != bSign) 264 return aSign && ((bits64) ((a | b) << 1) != 0); 265 return (a != b) && (aSign ^ (a < b)); 266 } 267 268 #endif 269