fpu/softfloat.h

   1 /*============================================================================
   2
   3 This C header file is part of the SoftFloat IEC/IEEE Floating-point Arithmetic
   4 Package, Release 2b.
   5
   6 Written by John R. Hauser.  This work was made possible in part by the
   7 International Computer Science Institute, located at Suite 600, 1947 Center
   8 Street, Berkeley, California 94704.  Funding was partially provided by the
   9 National Science Foundation under grant MIP-9311980.  The original version
  10 of this code was written as part of a project to build a fixed-point vector
  11 processor in collaboration with the University of California at Berkeley,
  12 overseen by Profs. Nelson Morgan and John Wawrzynek.  More information
  13 is available through the Web page `http://www.cs.berkeley.edu/~jhauser/
  14 arithmetic/SoftFloat.html'.
  15
  16 THIS SOFTWARE IS DISTRIBUTED AS IS, FOR FREE.  Although reasonable effort has
  17 been made to avoid it, THIS SOFTWARE MAY CONTAIN FAULTS THAT WILL AT TIMES
  18 RESULT IN INCORRECT BEHAVIOR.  USE OF THIS SOFTWARE IS RESTRICTED TO PERSONS
  19 AND ORGANIZATIONS WHO CAN AND WILL TAKE FULL RESPONSIBILITY FOR ALL LOSSES,
  20 COSTS, OR OTHER PROBLEMS THEY INCUR DUE TO THE SOFTWARE, AND WHO FURTHERMORE
  21 EFFECTIVELY INDEMNIFY JOHN HAUSER AND THE INTERNATIONAL COMPUTER SCIENCE
  22 INSTITUTE (possibly via similar legal warning) AGAINST ALL LOSSES, COSTS, OR
  23 OTHER PROBLEMS INCURRED BY THEIR CUSTOMERS AND CLIENTS DUE TO THE SOFTWARE.
  24
  25 Derivative works are acceptable, even for commercial purposes, so long as
  26 (1) the source code for the derivative work includes prominent notice that
  27 the work is derivative, and (2) the source code includes prominent notice with
  28 these four paragraphs for those parts of this code that are retained.
  29
  30 =============================================================================*/
  31
  32 #ifndef SOFTFLOAT_H
  33 #define SOFTFLOAT_H
  34
  35 #include <inttypes.h>
  36 #include "config.h"
  37
  38 /*----------------------------------------------------------------------------
  39 | Each of the following `typedef's defines the most convenient type that holds
  40 | integers of at least as many bits as specified.  For example, `uint8' should
  41 | be the most convenient type that can hold unsigned integers of as many as
  42 | 8 bits.  The `flag' type must be able to hold either a 0 or 1.  For most
  43 | implementations of C, `flag', `uint8', and `int8' should all be `typedef'ed
  44 | to the same as `int'.
  45 *----------------------------------------------------------------------------*/
  46 typedef char flag;
  47 typedef uint8_t uint8;
  48 typedef int8_t int8;
  49 typedef int uint16;
  50 typedef int int16;
  51 typedef unsigned int uint32;
  52 typedef signed int int32;
  53 typedef uint64_t uint64;
  54 typedef int64_t int64;
  55
  56 /*----------------------------------------------------------------------------
  57 | Each of the following `typedef's defines a type that holds integers
  58 | of _exactly_ the number of bits specified.  For instance, for most
  59 | implementation of C, `bits16' and `sbits16' should be `typedef'ed to
  60 | `unsigned short int' and `signed short int' (or `short int'), respectively.
  61 *----------------------------------------------------------------------------*/
  62 typedef uint8_t bits8;
  63 typedef int8_t sbits8;
  64 typedef uint16_t bits16;
  65 typedef int16_t sbits16;
  66 typedef uint32_t bits32;
  67 typedef int32_t sbits32;
  68 typedef uint64_t bits64;
  69 typedef int64_t sbits64;
  70
  71 #define LIT64( a ) a##LL
  72 #define INLINE static inline
  73
  74 /*----------------------------------------------------------------------------
  75 | The macro `FLOATX80' must be defined to enable the extended double-precision
  76 | floating-point format `floatx80'.  If this macro is not defined, the
  77 | `floatx80' type will not be defined, and none of the functions that either
  78 | input or output the `floatx80' type will be defined.  The same applies to
  79 | the `FLOAT128' macro and the quadruple-precision format `float128'.
  80 *----------------------------------------------------------------------------*/
  81 #ifdef CONFIG_SOFTFLOAT
  82 /* bit exact soft float support */
  83 #define FLOATX80
  84 #define FLOAT128
  85 #else
  86 /* native float support */
  87 #if (defined(__i386__) || defined(__x86_64__)) && !defined(_BSD)
  88 #define FLOATX80
  89 #endif
  90 #endif /* !CONFIG_SOFTFLOAT */
  91
  92 #define STATUS_PARAM , float_status *status
  93 #define STATUS(field) status->field
  94 #define STATUS_VAR , status
  95
  96 /*----------------------------------------------------------------------------
  97 | Software IEC/IEEE floating-point ordering relations
  98 *----------------------------------------------------------------------------*/
  99 enum {
 100     float_relation_less      = -1,
 101     float_relation_equal     =  0,
 102     float_relation_greater   =  1,
 103     float_relation_unordered =  2
 104 };
 105
 106 #ifdef CONFIG_SOFTFLOAT
 107 /*----------------------------------------------------------------------------
 108 | Software IEC/IEEE floating-point types.
 109 *----------------------------------------------------------------------------*/
 110 typedef uint32_t float32;
 111 typedef uint64_t float64;
 112 #ifdef FLOATX80
 113 typedef struct {
 114     uint64_t low;
 115     uint16_t high;
 116 } floatx80;
 117 #endif
 118 #ifdef FLOAT128
 119 typedef struct {
 120 #ifdef WORDS_BIGENDIAN
 121     uint64_t high, low;
 122 #else
 123     uint64_t low, high;
 124 #endif
 125 } float128;
 126 #endif
 127
 128 /*----------------------------------------------------------------------------
 129 | Software IEC/IEEE floating-point underflow tininess-detection mode.
 130 *----------------------------------------------------------------------------*/
 131 enum {
 132     float_tininess_after_rounding  = 0,
 133     float_tininess_before_rounding = 1
 134 };
 135
 136 /*----------------------------------------------------------------------------
 137 | Software IEC/IEEE floating-point rounding mode.
 138 *----------------------------------------------------------------------------*/
 139 enum {
 140     float_round_nearest_even = 0,
 141     float_round_down         = 1,
 142     float_round_up           = 2,
 143     float_round_to_zero      = 3
 144 };
 145
 146 /*----------------------------------------------------------------------------
 147 | Software IEC/IEEE floating-point exception flags.
 148 *----------------------------------------------------------------------------*/
 149 enum {
 150     float_flag_invalid   =  1,
 151     float_flag_divbyzero =  4,
 152     float_flag_overflow  =  8,
 153     float_flag_underflow = 16,
 154     float_flag_inexact   = 32
 155 };
 156
 157 typedef struct float_status {
 158     signed char float_detect_tininess;
 159     signed char float_rounding_mode;
 160     signed char float_exception_flags;
 161 #ifdef FLOATX80
 162     signed char floatx80_rounding_precision;
 163 #endif
 164 } float_status;
 165
 166 void set_float_rounding_mode(int val STATUS_PARAM);
 167 void set_float_exception_flags(int val STATUS_PARAM);
 168 INLINE int get_float_exception_flags(float_status *status)
 169 {
 170     return STATUS(float_exception_flags);
 171 }
 172 #ifdef FLOATX80
 173 void set_floatx80_rounding_precision(int val STATUS_PARAM);
 174 #endif
 175
 176 /*----------------------------------------------------------------------------
 177 | Routine to raise any or all of the software IEC/IEEE floating-point
 178 | exception flags.
 179 *----------------------------------------------------------------------------*/
 180 void float_raise( int8 flags STATUS_PARAM);
 181
 182 /*----------------------------------------------------------------------------
 183 | Software IEC/IEEE integer-to-floating-point conversion routines.
 184 *----------------------------------------------------------------------------*/
 185 float32 int32_to_float32( int STATUS_PARAM );
 186 float64 int32_to_float64( int STATUS_PARAM );
 187 float32 uint32_to_float32( unsigned int STATUS_PARAM );
 188 float64 uint32_to_float64( unsigned int STATUS_PARAM );
 189 #ifdef FLOATX80
 190 floatx80 int32_to_floatx80( int STATUS_PARAM );
 191 #endif
 192 #ifdef FLOAT128
 193 float128 int32_to_float128( int STATUS_PARAM );
 194 #endif
 195 float32 int64_to_float32( int64_t STATUS_PARAM );
 196 float64 int64_to_float64( int64_t STATUS_PARAM );
 197 #ifdef FLOATX80
 198 floatx80 int64_to_floatx80( int64_t STATUS_PARAM );
 199 #endif
 200 #ifdef FLOAT128
 201 float128 int64_to_float128( int64_t STATUS_PARAM );
 202 #endif
 203
 204 /*----------------------------------------------------------------------------
 205 | Software IEC/IEEE single-precision conversion routines.
 206 *----------------------------------------------------------------------------*/
 207 int float32_to_int32( float32 STATUS_PARAM );
 208 int float32_to_int32_round_to_zero( float32 STATUS_PARAM );
 209 unsigned int float32_to_uint32( float32 STATUS_PARAM );
 210 unsigned int float32_to_uint32_round_to_zero( float32 STATUS_PARAM );
 211 int64_t float32_to_int64( float32 STATUS_PARAM );
 212 int64_t float32_to_int64_round_to_zero( float32 STATUS_PARAM );
 213 float64 float32_to_float64( float32 STATUS_PARAM );
 214 #ifdef FLOATX80
 215 floatx80 float32_to_floatx80( float32 STATUS_PARAM );
 216 #endif
 217 #ifdef FLOAT128
 218 float128 float32_to_float128( float32 STATUS_PARAM );
 219 #endif
 220
 221 /*----------------------------------------------------------------------------
 222 | Software IEC/IEEE single-precision operations.
 223 *----------------------------------------------------------------------------*/
 224 float32 float32_round_to_int( float32 STATUS_PARAM );
 225 float32 float32_add( float32, float32 STATUS_PARAM );
 226 float32 float32_sub( float32, float32 STATUS_PARAM );
 227 float32 float32_mul( float32, float32 STATUS_PARAM );
 228 float32 float32_div( float32, float32 STATUS_PARAM );
 229 float32 float32_rem( float32, float32 STATUS_PARAM );
 230 float32 float32_sqrt( float32 STATUS_PARAM );
 231 char float32_eq( float32, float32 STATUS_PARAM );
 232 char float32_le( float32, float32 STATUS_PARAM );
 233 char float32_lt( float32, float32 STATUS_PARAM );
 234 char float32_eq_signaling( float32, float32 STATUS_PARAM );
 235 char float32_le_quiet( float32, float32 STATUS_PARAM );
 236 char float32_lt_quiet( float32, float32 STATUS_PARAM );
 237 char float32_compare( float32, float32 STATUS_PARAM );
 238 char float32_compare_quiet( float32, float32 STATUS_PARAM );
 239 char float32_is_signaling_nan( float32 );
 240
 241 INLINE float32 float32_abs(float32 a)
 242 {
 243     return a & 0x7fffffff;
 244 }
 245
 246 INLINE float32 float32_chs(float32 a)
 247 {
 248     return a ^ 0x80000000;
 249 }
 250
 251 /*----------------------------------------------------------------------------
 252 | Software IEC/IEEE double-precision conversion routines.
 253 *----------------------------------------------------------------------------*/
 254 int float64_to_int32( float64 STATUS_PARAM );
 255 int float64_to_int32_round_to_zero( float64 STATUS_PARAM );
 256 unsigned int float64_to_uint32( float64 STATUS_PARAM );
 257 unsigned int float64_to_uint32_round_to_zero( float64 STATUS_PARAM );
 258 int64_t float64_to_int64( float64 STATUS_PARAM );
 259 int64_t float64_to_int64_round_to_zero( float64 STATUS_PARAM );
 260 float32 float64_to_float32( float64 STATUS_PARAM );
 261 #ifdef FLOATX80
 262 floatx80 float64_to_floatx80( float64 STATUS_PARAM );
 263 #endif
 264 #ifdef FLOAT128
 265 float128 float64_to_float128( float64 STATUS_PARAM );
 266 #endif
 267
 268 /*----------------------------------------------------------------------------
 269 | Software IEC/IEEE double-precision operations.
 270 *----------------------------------------------------------------------------*/
 271 float64 float64_round_to_int( float64 STATUS_PARAM );
 272 float64 float64_add( float64, float64 STATUS_PARAM );
 273 float64 float64_sub( float64, float64 STATUS_PARAM );
 274 float64 float64_mul( float64, float64 STATUS_PARAM );
 275 float64 float64_div( float64, float64 STATUS_PARAM );
 276 float64 float64_rem( float64, float64 STATUS_PARAM );
 277 float64 float64_sqrt( float64 STATUS_PARAM );
 278 char float64_eq( float64, float64 STATUS_PARAM );
 279 char float64_le( float64, float64 STATUS_PARAM );
 280 char float64_lt( float64, float64 STATUS_PARAM );
 281 char float64_eq_signaling( float64, float64 STATUS_PARAM );
 282 char float64_le_quiet( float64, float64 STATUS_PARAM );
 283 char float64_lt_quiet( float64, float64 STATUS_PARAM );
 284 char float64_compare( float64, float64 STATUS_PARAM );
 285 char float64_compare_quiet( float64, float64 STATUS_PARAM );
 286 char float64_is_signaling_nan( float64 );
 287
 288 INLINE float64 float64_abs(float64 a)
 289 {
 290     return a & 0x7fffffffffffffffLL;
 291 }
 292
 293 INLINE float64 float64_chs(float64 a)
 294 {
 295     return a ^ 0x8000000000000000LL;
 296 }
 297
 298 #ifdef FLOATX80
 299
 300 /*----------------------------------------------------------------------------
 301 | Software IEC/IEEE extended double-precision conversion routines.
 302 *----------------------------------------------------------------------------*/
 303 int floatx80_to_int32( floatx80 STATUS_PARAM );
 304 int floatx80_to_int32_round_to_zero( floatx80 STATUS_PARAM );
 305 int64_t floatx80_to_int64( floatx80 STATUS_PARAM );
 306 int64_t floatx80_to_int64_round_to_zero( floatx80 STATUS_PARAM );
 307 float32 floatx80_to_float32( floatx80 STATUS_PARAM );
 308 float64 floatx80_to_float64( floatx80 STATUS_PARAM );
 309 #ifdef FLOAT128
 310 float128 floatx80_to_float128( floatx80 STATUS_PARAM );
 311 #endif
 312
 313 /*----------------------------------------------------------------------------
 314 | Software IEC/IEEE extended double-precision operations.
 315 *----------------------------------------------------------------------------*/
 316 floatx80 floatx80_round_to_int( floatx80 STATUS_PARAM );
 317 floatx80 floatx80_add( floatx80, floatx80 STATUS_PARAM );
 318 floatx80 floatx80_sub( floatx80, floatx80 STATUS_PARAM );
 319 floatx80 floatx80_mul( floatx80, floatx80 STATUS_PARAM );
 320 floatx80 floatx80_div( floatx80, floatx80 STATUS_PARAM );
 321 floatx80 floatx80_rem( floatx80, floatx80 STATUS_PARAM );
 322 floatx80 floatx80_sqrt( floatx80 STATUS_PARAM );
 323 char floatx80_eq( floatx80, floatx80 STATUS_PARAM );
 324 char floatx80_le( floatx80, floatx80 STATUS_PARAM );
 325 char floatx80_lt( floatx80, floatx80 STATUS_PARAM );
 326 char floatx80_eq_signaling( floatx80, floatx80 STATUS_PARAM );
 327 char floatx80_le_quiet( floatx80, floatx80 STATUS_PARAM );
 328 char floatx80_lt_quiet( floatx80, floatx80 STATUS_PARAM );
 329 char floatx80_is_signaling_nan( floatx80 );
 330
 331 INLINE floatx80 floatx80_abs(floatx80 a)
 332 {
 333     a.high &= 0x7fff;
 334     return a;
 335 }
 336
 337 INLINE floatx80 floatx80_chs(floatx80 a)
 338 {
 339     a.high ^= 0x8000;
 340     return a;
 341 }
 342
 343 #endif
 344
 345 #ifdef FLOAT128
 346
 347 /*----------------------------------------------------------------------------
 348 | Software IEC/IEEE quadruple-precision conversion routines.
 349 *----------------------------------------------------------------------------*/
 350 int float128_to_int32( float128 STATUS_PARAM );
 351 int float128_to_int32_round_to_zero( float128 STATUS_PARAM );
 352 int64_t float128_to_int64( float128 STATUS_PARAM );
 353 int64_t float128_to_int64_round_to_zero( float128 STATUS_PARAM );
 354 float32 float128_to_float32( float128 STATUS_PARAM );
 355 float64 float128_to_float64( float128 STATUS_PARAM );
 356 #ifdef FLOATX80
 357 floatx80 float128_to_floatx80( float128 STATUS_PARAM );
 358 #endif
 359
 360 /*----------------------------------------------------------------------------
 361 | Software IEC/IEEE quadruple-precision operations.
 362 *----------------------------------------------------------------------------*/
 363 float128 float128_round_to_int( float128 STATUS_PARAM );
 364 float128 float128_add( float128, float128 STATUS_PARAM );
 365 float128 float128_sub( float128, float128 STATUS_PARAM );
 366 float128 float128_mul( float128, float128 STATUS_PARAM );
 367 float128 float128_div( float128, float128 STATUS_PARAM );
 368 float128 float128_rem( float128, float128 STATUS_PARAM );
 369 float128 float128_sqrt( float128 STATUS_PARAM );
 370 char float128_eq( float128, float128 STATUS_PARAM );
 371 char float128_le( float128, float128 STATUS_PARAM );
 372 char float128_lt( float128, float128 STATUS_PARAM );
 373 char float128_eq_signaling( float128, float128 STATUS_PARAM );
 374 char float128_le_quiet( float128, float128 STATUS_PARAM );
 375 char float128_lt_quiet( float128, float128 STATUS_PARAM );
 376 char float128_is_signaling_nan( float128 );
 377
 378 INLINE float128 float128_abs(float128 a)
 379 {
 380     a.high &= 0x7fffffffffffffffLL;
 381     return a;
 382 }
 383
 384 INLINE float128 float128_chs(float128 a)
 385 {
 386     a.high ^= 0x8000000000000000LL;
 387     return a;
 388 }
 389
 390 #endif
 391
 392 #else /* CONFIG_SOFTFLOAT */
 393
 394 #include "softfloat-native.h"
 395
 396 #endif /* !CONFIG_SOFTFLOAT */
 397
 398 #endif /* !SOFTFLOAT_H */