Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | =============================================================================== |
| 3 | |
| 4 | This C source file is part of the SoftFloat IEC/IEEE Floating-point |
| 5 | Arithmetic Package, Release 2. |
| 6 | |
| 7 | Written by John R. Hauser. This work was made possible in part by the |
| 8 | International Computer Science Institute, located at Suite 600, 1947 Center |
| 9 | Street, Berkeley, California 94704. Funding was partially provided by the |
| 10 | National Science Foundation under grant MIP-9311980. The original version |
| 11 | of this code was written as part of a project to build a fixed-point vector |
| 12 | processor in collaboration with the University of California at Berkeley, |
| 13 | overseen by Profs. Nelson Morgan and John Wawrzynek. More information |
Justin P. Mattock | 50a23e6 | 2010-10-16 10:36:23 -0700 | [diff] [blame] | 14 | is available through the web page |
| 15 | http://www.jhauser.us/arithmetic/SoftFloat-2b/SoftFloat-source.txt |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 16 | |
| 17 | THIS SOFTWARE IS DISTRIBUTED AS IS, FOR FREE. Although reasonable effort |
| 18 | has been made to avoid it, THIS SOFTWARE MAY CONTAIN FAULTS THAT WILL AT |
| 19 | TIMES RESULT IN INCORRECT BEHAVIOR. USE OF THIS SOFTWARE IS RESTRICTED TO |
| 20 | PERSONS AND ORGANIZATIONS WHO CAN AND WILL TAKE FULL RESPONSIBILITY FOR ANY |
| 21 | AND ALL LOSSES, COSTS, OR OTHER PROBLEMS ARISING FROM ITS USE. |
| 22 | |
| 23 | Derivative works are acceptable, even for commercial purposes, so long as |
| 24 | (1) they include prominent notice that the work is derivative, and (2) they |
| 25 | include prominent notice akin to these three paragraphs for those parts of |
| 26 | this code that are retained. |
| 27 | |
| 28 | =============================================================================== |
| 29 | */ |
| 30 | |
Nicolas Pitre | c1241c4c | 2005-06-23 21:56:46 +0100 | [diff] [blame] | 31 | #include <asm/div64.h> |
| 32 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 33 | #include "fpa11.h" |
| 34 | //#include "milieu.h" |
| 35 | //#include "softfloat.h" |
| 36 | |
| 37 | /* |
| 38 | ------------------------------------------------------------------------------- |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 39 | Primitive arithmetic functions, including multi-word arithmetic, and |
| 40 | division and square root approximations. (Can be specialized to target if |
| 41 | desired.) |
| 42 | ------------------------------------------------------------------------------- |
| 43 | */ |
| 44 | #include "softfloat-macros" |
| 45 | |
| 46 | /* |
| 47 | ------------------------------------------------------------------------------- |
| 48 | Functions and definitions to determine: (1) whether tininess for underflow |
| 49 | is detected before or after rounding by default, (2) what (if anything) |
| 50 | happens when exceptions are raised, (3) how signaling NaNs are distinguished |
| 51 | from quiet NaNs, (4) the default generated quiet NaNs, and (5) how NaNs |
| 52 | are propagated from function inputs to output. These details are target- |
| 53 | specific. |
| 54 | ------------------------------------------------------------------------------- |
| 55 | */ |
| 56 | #include "softfloat-specialize" |
| 57 | |
| 58 | /* |
| 59 | ------------------------------------------------------------------------------- |
| 60 | Takes a 64-bit fixed-point value `absZ' with binary point between bits 6 |
| 61 | and 7, and returns the properly rounded 32-bit integer corresponding to the |
| 62 | input. If `zSign' is nonzero, the input is negated before being converted |
| 63 | to an integer. Bit 63 of `absZ' must be zero. Ordinarily, the fixed-point |
| 64 | input is simply rounded to an integer, with the inexact exception raised if |
| 65 | the input cannot be represented exactly as an integer. If the fixed-point |
| 66 | input is too large, however, the invalid exception is raised and the largest |
| 67 | positive or negative integer is returned. |
| 68 | ------------------------------------------------------------------------------- |
| 69 | */ |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 70 | static int32 roundAndPackInt32( struct roundingData *roundData, flag zSign, bits64 absZ ) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 71 | { |
| 72 | int8 roundingMode; |
| 73 | flag roundNearestEven; |
| 74 | int8 roundIncrement, roundBits; |
| 75 | int32 z; |
| 76 | |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 77 | roundingMode = roundData->mode; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 78 | roundNearestEven = ( roundingMode == float_round_nearest_even ); |
| 79 | roundIncrement = 0x40; |
| 80 | if ( ! roundNearestEven ) { |
| 81 | if ( roundingMode == float_round_to_zero ) { |
| 82 | roundIncrement = 0; |
| 83 | } |
| 84 | else { |
| 85 | roundIncrement = 0x7F; |
| 86 | if ( zSign ) { |
| 87 | if ( roundingMode == float_round_up ) roundIncrement = 0; |
| 88 | } |
| 89 | else { |
| 90 | if ( roundingMode == float_round_down ) roundIncrement = 0; |
| 91 | } |
| 92 | } |
| 93 | } |
| 94 | roundBits = absZ & 0x7F; |
| 95 | absZ = ( absZ + roundIncrement )>>7; |
| 96 | absZ &= ~ ( ( ( roundBits ^ 0x40 ) == 0 ) & roundNearestEven ); |
| 97 | z = absZ; |
| 98 | if ( zSign ) z = - z; |
| 99 | if ( ( absZ>>32 ) || ( z && ( ( z < 0 ) ^ zSign ) ) ) { |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 100 | roundData->exception |= float_flag_invalid; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 101 | return zSign ? 0x80000000 : 0x7FFFFFFF; |
| 102 | } |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 103 | if ( roundBits ) roundData->exception |= float_flag_inexact; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 104 | return z; |
| 105 | |
| 106 | } |
| 107 | |
| 108 | /* |
| 109 | ------------------------------------------------------------------------------- |
| 110 | Returns the fraction bits of the single-precision floating-point value `a'. |
| 111 | ------------------------------------------------------------------------------- |
| 112 | */ |
| 113 | INLINE bits32 extractFloat32Frac( float32 a ) |
| 114 | { |
| 115 | |
| 116 | return a & 0x007FFFFF; |
| 117 | |
| 118 | } |
| 119 | |
| 120 | /* |
| 121 | ------------------------------------------------------------------------------- |
| 122 | Returns the exponent bits of the single-precision floating-point value `a'. |
| 123 | ------------------------------------------------------------------------------- |
| 124 | */ |
| 125 | INLINE int16 extractFloat32Exp( float32 a ) |
| 126 | { |
| 127 | |
| 128 | return ( a>>23 ) & 0xFF; |
| 129 | |
| 130 | } |
| 131 | |
| 132 | /* |
| 133 | ------------------------------------------------------------------------------- |
| 134 | Returns the sign bit of the single-precision floating-point value `a'. |
| 135 | ------------------------------------------------------------------------------- |
| 136 | */ |
| 137 | #if 0 /* in softfloat.h */ |
| 138 | INLINE flag extractFloat32Sign( float32 a ) |
| 139 | { |
| 140 | |
| 141 | return a>>31; |
| 142 | |
| 143 | } |
| 144 | #endif |
| 145 | |
| 146 | /* |
| 147 | ------------------------------------------------------------------------------- |
| 148 | Normalizes the subnormal single-precision floating-point value represented |
| 149 | by the denormalized significand `aSig'. The normalized exponent and |
| 150 | significand are stored at the locations pointed to by `zExpPtr' and |
| 151 | `zSigPtr', respectively. |
| 152 | ------------------------------------------------------------------------------- |
| 153 | */ |
| 154 | static void |
| 155 | normalizeFloat32Subnormal( bits32 aSig, int16 *zExpPtr, bits32 *zSigPtr ) |
| 156 | { |
| 157 | int8 shiftCount; |
| 158 | |
| 159 | shiftCount = countLeadingZeros32( aSig ) - 8; |
| 160 | *zSigPtr = aSig<<shiftCount; |
| 161 | *zExpPtr = 1 - shiftCount; |
| 162 | |
| 163 | } |
| 164 | |
| 165 | /* |
| 166 | ------------------------------------------------------------------------------- |
| 167 | Packs the sign `zSign', exponent `zExp', and significand `zSig' into a |
| 168 | single-precision floating-point value, returning the result. After being |
| 169 | shifted into the proper positions, the three fields are simply added |
| 170 | together to form the result. This means that any integer portion of `zSig' |
| 171 | will be added into the exponent. Since a properly normalized significand |
| 172 | will have an integer portion equal to 1, the `zExp' input should be 1 less |
| 173 | than the desired result exponent whenever `zSig' is a complete, normalized |
| 174 | significand. |
| 175 | ------------------------------------------------------------------------------- |
| 176 | */ |
| 177 | INLINE float32 packFloat32( flag zSign, int16 zExp, bits32 zSig ) |
| 178 | { |
| 179 | #if 0 |
| 180 | float32 f; |
| 181 | __asm__("@ packFloat32 \n\ |
| 182 | mov %0, %1, asl #31 \n\ |
| 183 | orr %0, %2, asl #23 \n\ |
| 184 | orr %0, %3" |
| 185 | : /* no outputs */ |
| 186 | : "g" (f), "g" (zSign), "g" (zExp), "g" (zSig) |
| 187 | : "cc"); |
| 188 | return f; |
| 189 | #else |
| 190 | return ( ( (bits32) zSign )<<31 ) + ( ( (bits32) zExp )<<23 ) + zSig; |
| 191 | #endif |
| 192 | } |
| 193 | |
| 194 | /* |
| 195 | ------------------------------------------------------------------------------- |
| 196 | Takes an abstract floating-point value having sign `zSign', exponent `zExp', |
| 197 | and significand `zSig', and returns the proper single-precision floating- |
| 198 | point value corresponding to the abstract input. Ordinarily, the abstract |
| 199 | value is simply rounded and packed into the single-precision format, with |
| 200 | the inexact exception raised if the abstract input cannot be represented |
| 201 | exactly. If the abstract value is too large, however, the overflow and |
| 202 | inexact exceptions are raised and an infinity or maximal finite value is |
| 203 | returned. If the abstract value is too small, the input value is rounded to |
| 204 | a subnormal number, and the underflow and inexact exceptions are raised if |
| 205 | the abstract input cannot be represented exactly as a subnormal single- |
| 206 | precision floating-point number. |
| 207 | The input significand `zSig' has its binary point between bits 30 |
| 208 | and 29, which is 7 bits to the left of the usual location. This shifted |
| 209 | significand must be normalized or smaller. If `zSig' is not normalized, |
| 210 | `zExp' must be 0; in that case, the result returned is a subnormal number, |
| 211 | and it must not require rounding. In the usual case that `zSig' is |
| 212 | normalized, `zExp' must be 1 less than the ``true'' floating-point exponent. |
| 213 | The handling of underflow and overflow follows the IEC/IEEE Standard for |
| 214 | Binary Floating-point Arithmetic. |
| 215 | ------------------------------------------------------------------------------- |
| 216 | */ |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 217 | static float32 roundAndPackFloat32( struct roundingData *roundData, flag zSign, int16 zExp, bits32 zSig ) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 218 | { |
| 219 | int8 roundingMode; |
| 220 | flag roundNearestEven; |
| 221 | int8 roundIncrement, roundBits; |
| 222 | flag isTiny; |
| 223 | |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 224 | roundingMode = roundData->mode; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 225 | roundNearestEven = ( roundingMode == float_round_nearest_even ); |
| 226 | roundIncrement = 0x40; |
| 227 | if ( ! roundNearestEven ) { |
| 228 | if ( roundingMode == float_round_to_zero ) { |
| 229 | roundIncrement = 0; |
| 230 | } |
| 231 | else { |
| 232 | roundIncrement = 0x7F; |
| 233 | if ( zSign ) { |
| 234 | if ( roundingMode == float_round_up ) roundIncrement = 0; |
| 235 | } |
| 236 | else { |
| 237 | if ( roundingMode == float_round_down ) roundIncrement = 0; |
| 238 | } |
| 239 | } |
| 240 | } |
| 241 | roundBits = zSig & 0x7F; |
| 242 | if ( 0xFD <= (bits16) zExp ) { |
| 243 | if ( ( 0xFD < zExp ) |
| 244 | || ( ( zExp == 0xFD ) |
| 245 | && ( (sbits32) ( zSig + roundIncrement ) < 0 ) ) |
| 246 | ) { |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 247 | roundData->exception |= float_flag_overflow | float_flag_inexact; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 248 | return packFloat32( zSign, 0xFF, 0 ) - ( roundIncrement == 0 ); |
| 249 | } |
| 250 | if ( zExp < 0 ) { |
| 251 | isTiny = |
| 252 | ( float_detect_tininess == float_tininess_before_rounding ) |
| 253 | || ( zExp < -1 ) |
| 254 | || ( zSig + roundIncrement < 0x80000000 ); |
| 255 | shift32RightJamming( zSig, - zExp, &zSig ); |
| 256 | zExp = 0; |
| 257 | roundBits = zSig & 0x7F; |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 258 | if ( isTiny && roundBits ) roundData->exception |= float_flag_underflow; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 259 | } |
| 260 | } |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 261 | if ( roundBits ) roundData->exception |= float_flag_inexact; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 262 | zSig = ( zSig + roundIncrement )>>7; |
| 263 | zSig &= ~ ( ( ( roundBits ^ 0x40 ) == 0 ) & roundNearestEven ); |
| 264 | if ( zSig == 0 ) zExp = 0; |
| 265 | return packFloat32( zSign, zExp, zSig ); |
| 266 | |
| 267 | } |
| 268 | |
| 269 | /* |
| 270 | ------------------------------------------------------------------------------- |
| 271 | Takes an abstract floating-point value having sign `zSign', exponent `zExp', |
| 272 | and significand `zSig', and returns the proper single-precision floating- |
| 273 | point value corresponding to the abstract input. This routine is just like |
| 274 | `roundAndPackFloat32' except that `zSig' does not have to be normalized in |
| 275 | any way. In all cases, `zExp' must be 1 less than the ``true'' floating- |
| 276 | point exponent. |
| 277 | ------------------------------------------------------------------------------- |
| 278 | */ |
| 279 | static float32 |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 280 | normalizeRoundAndPackFloat32( struct roundingData *roundData, flag zSign, int16 zExp, bits32 zSig ) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 281 | { |
| 282 | int8 shiftCount; |
| 283 | |
| 284 | shiftCount = countLeadingZeros32( zSig ) - 1; |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 285 | return roundAndPackFloat32( roundData, zSign, zExp - shiftCount, zSig<<shiftCount ); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 286 | |
| 287 | } |
| 288 | |
| 289 | /* |
| 290 | ------------------------------------------------------------------------------- |
| 291 | Returns the fraction bits of the double-precision floating-point value `a'. |
| 292 | ------------------------------------------------------------------------------- |
| 293 | */ |
| 294 | INLINE bits64 extractFloat64Frac( float64 a ) |
| 295 | { |
| 296 | |
| 297 | return a & LIT64( 0x000FFFFFFFFFFFFF ); |
| 298 | |
| 299 | } |
| 300 | |
| 301 | /* |
| 302 | ------------------------------------------------------------------------------- |
| 303 | Returns the exponent bits of the double-precision floating-point value `a'. |
| 304 | ------------------------------------------------------------------------------- |
| 305 | */ |
| 306 | INLINE int16 extractFloat64Exp( float64 a ) |
| 307 | { |
| 308 | |
| 309 | return ( a>>52 ) & 0x7FF; |
| 310 | |
| 311 | } |
| 312 | |
| 313 | /* |
| 314 | ------------------------------------------------------------------------------- |
| 315 | Returns the sign bit of the double-precision floating-point value `a'. |
| 316 | ------------------------------------------------------------------------------- |
| 317 | */ |
| 318 | #if 0 /* in softfloat.h */ |
| 319 | INLINE flag extractFloat64Sign( float64 a ) |
| 320 | { |
| 321 | |
| 322 | return a>>63; |
| 323 | |
| 324 | } |
| 325 | #endif |
| 326 | |
| 327 | /* |
| 328 | ------------------------------------------------------------------------------- |
| 329 | Normalizes the subnormal double-precision floating-point value represented |
| 330 | by the denormalized significand `aSig'. The normalized exponent and |
| 331 | significand are stored at the locations pointed to by `zExpPtr' and |
| 332 | `zSigPtr', respectively. |
| 333 | ------------------------------------------------------------------------------- |
| 334 | */ |
| 335 | static void |
| 336 | normalizeFloat64Subnormal( bits64 aSig, int16 *zExpPtr, bits64 *zSigPtr ) |
| 337 | { |
| 338 | int8 shiftCount; |
| 339 | |
| 340 | shiftCount = countLeadingZeros64( aSig ) - 11; |
| 341 | *zSigPtr = aSig<<shiftCount; |
| 342 | *zExpPtr = 1 - shiftCount; |
| 343 | |
| 344 | } |
| 345 | |
| 346 | /* |
| 347 | ------------------------------------------------------------------------------- |
| 348 | Packs the sign `zSign', exponent `zExp', and significand `zSig' into a |
| 349 | double-precision floating-point value, returning the result. After being |
| 350 | shifted into the proper positions, the three fields are simply added |
| 351 | together to form the result. This means that any integer portion of `zSig' |
| 352 | will be added into the exponent. Since a properly normalized significand |
| 353 | will have an integer portion equal to 1, the `zExp' input should be 1 less |
| 354 | than the desired result exponent whenever `zSig' is a complete, normalized |
| 355 | significand. |
| 356 | ------------------------------------------------------------------------------- |
| 357 | */ |
| 358 | INLINE float64 packFloat64( flag zSign, int16 zExp, bits64 zSig ) |
| 359 | { |
| 360 | |
| 361 | return ( ( (bits64) zSign )<<63 ) + ( ( (bits64) zExp )<<52 ) + zSig; |
| 362 | |
| 363 | } |
| 364 | |
| 365 | /* |
| 366 | ------------------------------------------------------------------------------- |
| 367 | Takes an abstract floating-point value having sign `zSign', exponent `zExp', |
| 368 | and significand `zSig', and returns the proper double-precision floating- |
| 369 | point value corresponding to the abstract input. Ordinarily, the abstract |
| 370 | value is simply rounded and packed into the double-precision format, with |
| 371 | the inexact exception raised if the abstract input cannot be represented |
| 372 | exactly. If the abstract value is too large, however, the overflow and |
| 373 | inexact exceptions are raised and an infinity or maximal finite value is |
| 374 | returned. If the abstract value is too small, the input value is rounded to |
| 375 | a subnormal number, and the underflow and inexact exceptions are raised if |
| 376 | the abstract input cannot be represented exactly as a subnormal double- |
| 377 | precision floating-point number. |
| 378 | The input significand `zSig' has its binary point between bits 62 |
| 379 | and 61, which is 10 bits to the left of the usual location. This shifted |
| 380 | significand must be normalized or smaller. If `zSig' is not normalized, |
| 381 | `zExp' must be 0; in that case, the result returned is a subnormal number, |
| 382 | and it must not require rounding. In the usual case that `zSig' is |
| 383 | normalized, `zExp' must be 1 less than the ``true'' floating-point exponent. |
| 384 | The handling of underflow and overflow follows the IEC/IEEE Standard for |
| 385 | Binary Floating-point Arithmetic. |
| 386 | ------------------------------------------------------------------------------- |
| 387 | */ |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 388 | static float64 roundAndPackFloat64( struct roundingData *roundData, flag zSign, int16 zExp, bits64 zSig ) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 389 | { |
| 390 | int8 roundingMode; |
| 391 | flag roundNearestEven; |
| 392 | int16 roundIncrement, roundBits; |
| 393 | flag isTiny; |
| 394 | |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 395 | roundingMode = roundData->mode; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 396 | roundNearestEven = ( roundingMode == float_round_nearest_even ); |
| 397 | roundIncrement = 0x200; |
| 398 | if ( ! roundNearestEven ) { |
| 399 | if ( roundingMode == float_round_to_zero ) { |
| 400 | roundIncrement = 0; |
| 401 | } |
| 402 | else { |
| 403 | roundIncrement = 0x3FF; |
| 404 | if ( zSign ) { |
| 405 | if ( roundingMode == float_round_up ) roundIncrement = 0; |
| 406 | } |
| 407 | else { |
| 408 | if ( roundingMode == float_round_down ) roundIncrement = 0; |
| 409 | } |
| 410 | } |
| 411 | } |
| 412 | roundBits = zSig & 0x3FF; |
| 413 | if ( 0x7FD <= (bits16) zExp ) { |
| 414 | if ( ( 0x7FD < zExp ) |
| 415 | || ( ( zExp == 0x7FD ) |
| 416 | && ( (sbits64) ( zSig + roundIncrement ) < 0 ) ) |
| 417 | ) { |
| 418 | //register int lr = __builtin_return_address(0); |
| 419 | //printk("roundAndPackFloat64 called from 0x%08x\n",lr); |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 420 | roundData->exception |= float_flag_overflow | float_flag_inexact; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 421 | return packFloat64( zSign, 0x7FF, 0 ) - ( roundIncrement == 0 ); |
| 422 | } |
| 423 | if ( zExp < 0 ) { |
| 424 | isTiny = |
| 425 | ( float_detect_tininess == float_tininess_before_rounding ) |
| 426 | || ( zExp < -1 ) |
| 427 | || ( zSig + roundIncrement < LIT64( 0x8000000000000000 ) ); |
| 428 | shift64RightJamming( zSig, - zExp, &zSig ); |
| 429 | zExp = 0; |
| 430 | roundBits = zSig & 0x3FF; |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 431 | if ( isTiny && roundBits ) roundData->exception |= float_flag_underflow; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 432 | } |
| 433 | } |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 434 | if ( roundBits ) roundData->exception |= float_flag_inexact; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 435 | zSig = ( zSig + roundIncrement )>>10; |
| 436 | zSig &= ~ ( ( ( roundBits ^ 0x200 ) == 0 ) & roundNearestEven ); |
| 437 | if ( zSig == 0 ) zExp = 0; |
| 438 | return packFloat64( zSign, zExp, zSig ); |
| 439 | |
| 440 | } |
| 441 | |
| 442 | /* |
| 443 | ------------------------------------------------------------------------------- |
| 444 | Takes an abstract floating-point value having sign `zSign', exponent `zExp', |
| 445 | and significand `zSig', and returns the proper double-precision floating- |
| 446 | point value corresponding to the abstract input. This routine is just like |
| 447 | `roundAndPackFloat64' except that `zSig' does not have to be normalized in |
| 448 | any way. In all cases, `zExp' must be 1 less than the ``true'' floating- |
| 449 | point exponent. |
| 450 | ------------------------------------------------------------------------------- |
| 451 | */ |
| 452 | static float64 |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 453 | normalizeRoundAndPackFloat64( struct roundingData *roundData, flag zSign, int16 zExp, bits64 zSig ) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 454 | { |
| 455 | int8 shiftCount; |
| 456 | |
| 457 | shiftCount = countLeadingZeros64( zSig ) - 1; |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 458 | return roundAndPackFloat64( roundData, zSign, zExp - shiftCount, zSig<<shiftCount ); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 459 | |
| 460 | } |
| 461 | |
| 462 | #ifdef FLOATX80 |
| 463 | |
| 464 | /* |
| 465 | ------------------------------------------------------------------------------- |
| 466 | Returns the fraction bits of the extended double-precision floating-point |
| 467 | value `a'. |
| 468 | ------------------------------------------------------------------------------- |
| 469 | */ |
| 470 | INLINE bits64 extractFloatx80Frac( floatx80 a ) |
| 471 | { |
| 472 | |
| 473 | return a.low; |
| 474 | |
| 475 | } |
| 476 | |
| 477 | /* |
| 478 | ------------------------------------------------------------------------------- |
| 479 | Returns the exponent bits of the extended double-precision floating-point |
| 480 | value `a'. |
| 481 | ------------------------------------------------------------------------------- |
| 482 | */ |
| 483 | INLINE int32 extractFloatx80Exp( floatx80 a ) |
| 484 | { |
| 485 | |
| 486 | return a.high & 0x7FFF; |
| 487 | |
| 488 | } |
| 489 | |
| 490 | /* |
| 491 | ------------------------------------------------------------------------------- |
| 492 | Returns the sign bit of the extended double-precision floating-point value |
| 493 | `a'. |
| 494 | ------------------------------------------------------------------------------- |
| 495 | */ |
| 496 | INLINE flag extractFloatx80Sign( floatx80 a ) |
| 497 | { |
| 498 | |
| 499 | return a.high>>15; |
| 500 | |
| 501 | } |
| 502 | |
| 503 | /* |
| 504 | ------------------------------------------------------------------------------- |
| 505 | Normalizes the subnormal extended double-precision floating-point value |
| 506 | represented by the denormalized significand `aSig'. The normalized exponent |
| 507 | and significand are stored at the locations pointed to by `zExpPtr' and |
| 508 | `zSigPtr', respectively. |
| 509 | ------------------------------------------------------------------------------- |
| 510 | */ |
| 511 | static void |
| 512 | normalizeFloatx80Subnormal( bits64 aSig, int32 *zExpPtr, bits64 *zSigPtr ) |
| 513 | { |
| 514 | int8 shiftCount; |
| 515 | |
| 516 | shiftCount = countLeadingZeros64( aSig ); |
| 517 | *zSigPtr = aSig<<shiftCount; |
| 518 | *zExpPtr = 1 - shiftCount; |
| 519 | |
| 520 | } |
| 521 | |
| 522 | /* |
| 523 | ------------------------------------------------------------------------------- |
| 524 | Packs the sign `zSign', exponent `zExp', and significand `zSig' into an |
| 525 | extended double-precision floating-point value, returning the result. |
| 526 | ------------------------------------------------------------------------------- |
| 527 | */ |
| 528 | INLINE floatx80 packFloatx80( flag zSign, int32 zExp, bits64 zSig ) |
| 529 | { |
| 530 | floatx80 z; |
| 531 | |
| 532 | z.low = zSig; |
| 533 | z.high = ( ( (bits16) zSign )<<15 ) + zExp; |
Lennert Buytenhek | 06c03ca | 2005-11-07 21:12:07 +0000 | [diff] [blame] | 534 | z.__padding = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 535 | return z; |
| 536 | |
| 537 | } |
| 538 | |
| 539 | /* |
| 540 | ------------------------------------------------------------------------------- |
| 541 | Takes an abstract floating-point value having sign `zSign', exponent `zExp', |
| 542 | and extended significand formed by the concatenation of `zSig0' and `zSig1', |
| 543 | and returns the proper extended double-precision floating-point value |
| 544 | corresponding to the abstract input. Ordinarily, the abstract value is |
| 545 | rounded and packed into the extended double-precision format, with the |
| 546 | inexact exception raised if the abstract input cannot be represented |
| 547 | exactly. If the abstract value is too large, however, the overflow and |
| 548 | inexact exceptions are raised and an infinity or maximal finite value is |
| 549 | returned. If the abstract value is too small, the input value is rounded to |
| 550 | a subnormal number, and the underflow and inexact exceptions are raised if |
| 551 | the abstract input cannot be represented exactly as a subnormal extended |
| 552 | double-precision floating-point number. |
| 553 | If `roundingPrecision' is 32 or 64, the result is rounded to the same |
| 554 | number of bits as single or double precision, respectively. Otherwise, the |
| 555 | result is rounded to the full precision of the extended double-precision |
| 556 | format. |
| 557 | The input significand must be normalized or smaller. If the input |
| 558 | significand is not normalized, `zExp' must be 0; in that case, the result |
| 559 | returned is a subnormal number, and it must not require rounding. The |
| 560 | handling of underflow and overflow follows the IEC/IEEE Standard for Binary |
| 561 | Floating-point Arithmetic. |
| 562 | ------------------------------------------------------------------------------- |
| 563 | */ |
| 564 | static floatx80 |
| 565 | roundAndPackFloatx80( |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 566 | struct roundingData *roundData, flag zSign, int32 zExp, bits64 zSig0, bits64 zSig1 |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 567 | ) |
| 568 | { |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 569 | int8 roundingMode, roundingPrecision; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 570 | flag roundNearestEven, increment, isTiny; |
| 571 | int64 roundIncrement, roundMask, roundBits; |
| 572 | |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 573 | roundingMode = roundData->mode; |
| 574 | roundingPrecision = roundData->precision; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 575 | roundNearestEven = ( roundingMode == float_round_nearest_even ); |
| 576 | if ( roundingPrecision == 80 ) goto precision80; |
| 577 | if ( roundingPrecision == 64 ) { |
| 578 | roundIncrement = LIT64( 0x0000000000000400 ); |
| 579 | roundMask = LIT64( 0x00000000000007FF ); |
| 580 | } |
| 581 | else if ( roundingPrecision == 32 ) { |
| 582 | roundIncrement = LIT64( 0x0000008000000000 ); |
| 583 | roundMask = LIT64( 0x000000FFFFFFFFFF ); |
| 584 | } |
| 585 | else { |
| 586 | goto precision80; |
| 587 | } |
| 588 | zSig0 |= ( zSig1 != 0 ); |
| 589 | if ( ! roundNearestEven ) { |
| 590 | if ( roundingMode == float_round_to_zero ) { |
| 591 | roundIncrement = 0; |
| 592 | } |
| 593 | else { |
| 594 | roundIncrement = roundMask; |
| 595 | if ( zSign ) { |
| 596 | if ( roundingMode == float_round_up ) roundIncrement = 0; |
| 597 | } |
| 598 | else { |
| 599 | if ( roundingMode == float_round_down ) roundIncrement = 0; |
| 600 | } |
| 601 | } |
| 602 | } |
| 603 | roundBits = zSig0 & roundMask; |
| 604 | if ( 0x7FFD <= (bits32) ( zExp - 1 ) ) { |
| 605 | if ( ( 0x7FFE < zExp ) |
| 606 | || ( ( zExp == 0x7FFE ) && ( zSig0 + roundIncrement < zSig0 ) ) |
| 607 | ) { |
| 608 | goto overflow; |
| 609 | } |
| 610 | if ( zExp <= 0 ) { |
| 611 | isTiny = |
| 612 | ( float_detect_tininess == float_tininess_before_rounding ) |
| 613 | || ( zExp < 0 ) |
| 614 | || ( zSig0 <= zSig0 + roundIncrement ); |
| 615 | shift64RightJamming( zSig0, 1 - zExp, &zSig0 ); |
| 616 | zExp = 0; |
| 617 | roundBits = zSig0 & roundMask; |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 618 | if ( isTiny && roundBits ) roundData->exception |= float_flag_underflow; |
| 619 | if ( roundBits ) roundData->exception |= float_flag_inexact; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 620 | zSig0 += roundIncrement; |
| 621 | if ( (sbits64) zSig0 < 0 ) zExp = 1; |
| 622 | roundIncrement = roundMask + 1; |
| 623 | if ( roundNearestEven && ( roundBits<<1 == roundIncrement ) ) { |
| 624 | roundMask |= roundIncrement; |
| 625 | } |
| 626 | zSig0 &= ~ roundMask; |
| 627 | return packFloatx80( zSign, zExp, zSig0 ); |
| 628 | } |
| 629 | } |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 630 | if ( roundBits ) roundData->exception |= float_flag_inexact; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 631 | zSig0 += roundIncrement; |
| 632 | if ( zSig0 < roundIncrement ) { |
| 633 | ++zExp; |
| 634 | zSig0 = LIT64( 0x8000000000000000 ); |
| 635 | } |
| 636 | roundIncrement = roundMask + 1; |
| 637 | if ( roundNearestEven && ( roundBits<<1 == roundIncrement ) ) { |
| 638 | roundMask |= roundIncrement; |
| 639 | } |
| 640 | zSig0 &= ~ roundMask; |
| 641 | if ( zSig0 == 0 ) zExp = 0; |
| 642 | return packFloatx80( zSign, zExp, zSig0 ); |
| 643 | precision80: |
| 644 | increment = ( (sbits64) zSig1 < 0 ); |
| 645 | if ( ! roundNearestEven ) { |
| 646 | if ( roundingMode == float_round_to_zero ) { |
| 647 | increment = 0; |
| 648 | } |
| 649 | else { |
| 650 | if ( zSign ) { |
| 651 | increment = ( roundingMode == float_round_down ) && zSig1; |
| 652 | } |
| 653 | else { |
| 654 | increment = ( roundingMode == float_round_up ) && zSig1; |
| 655 | } |
| 656 | } |
| 657 | } |
| 658 | if ( 0x7FFD <= (bits32) ( zExp - 1 ) ) { |
| 659 | if ( ( 0x7FFE < zExp ) |
| 660 | || ( ( zExp == 0x7FFE ) |
| 661 | && ( zSig0 == LIT64( 0xFFFFFFFFFFFFFFFF ) ) |
| 662 | && increment |
| 663 | ) |
| 664 | ) { |
| 665 | roundMask = 0; |
| 666 | overflow: |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 667 | roundData->exception |= float_flag_overflow | float_flag_inexact; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 668 | if ( ( roundingMode == float_round_to_zero ) |
| 669 | || ( zSign && ( roundingMode == float_round_up ) ) |
| 670 | || ( ! zSign && ( roundingMode == float_round_down ) ) |
| 671 | ) { |
| 672 | return packFloatx80( zSign, 0x7FFE, ~ roundMask ); |
| 673 | } |
| 674 | return packFloatx80( zSign, 0x7FFF, LIT64( 0x8000000000000000 ) ); |
| 675 | } |
| 676 | if ( zExp <= 0 ) { |
| 677 | isTiny = |
| 678 | ( float_detect_tininess == float_tininess_before_rounding ) |
| 679 | || ( zExp < 0 ) |
| 680 | || ! increment |
| 681 | || ( zSig0 < LIT64( 0xFFFFFFFFFFFFFFFF ) ); |
| 682 | shift64ExtraRightJamming( zSig0, zSig1, 1 - zExp, &zSig0, &zSig1 ); |
| 683 | zExp = 0; |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 684 | if ( isTiny && zSig1 ) roundData->exception |= float_flag_underflow; |
| 685 | if ( zSig1 ) roundData->exception |= float_flag_inexact; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 686 | if ( roundNearestEven ) { |
| 687 | increment = ( (sbits64) zSig1 < 0 ); |
| 688 | } |
| 689 | else { |
| 690 | if ( zSign ) { |
| 691 | increment = ( roundingMode == float_round_down ) && zSig1; |
| 692 | } |
| 693 | else { |
| 694 | increment = ( roundingMode == float_round_up ) && zSig1; |
| 695 | } |
| 696 | } |
| 697 | if ( increment ) { |
| 698 | ++zSig0; |
| 699 | zSig0 &= ~ ( ( zSig1 + zSig1 == 0 ) & roundNearestEven ); |
| 700 | if ( (sbits64) zSig0 < 0 ) zExp = 1; |
| 701 | } |
| 702 | return packFloatx80( zSign, zExp, zSig0 ); |
| 703 | } |
| 704 | } |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 705 | if ( zSig1 ) roundData->exception |= float_flag_inexact; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 706 | if ( increment ) { |
| 707 | ++zSig0; |
| 708 | if ( zSig0 == 0 ) { |
| 709 | ++zExp; |
| 710 | zSig0 = LIT64( 0x8000000000000000 ); |
| 711 | } |
| 712 | else { |
| 713 | zSig0 &= ~ ( ( zSig1 + zSig1 == 0 ) & roundNearestEven ); |
| 714 | } |
| 715 | } |
| 716 | else { |
| 717 | if ( zSig0 == 0 ) zExp = 0; |
| 718 | } |
| 719 | |
| 720 | return packFloatx80( zSign, zExp, zSig0 ); |
| 721 | } |
| 722 | |
| 723 | /* |
| 724 | ------------------------------------------------------------------------------- |
| 725 | Takes an abstract floating-point value having sign `zSign', exponent |
| 726 | `zExp', and significand formed by the concatenation of `zSig0' and `zSig1', |
| 727 | and returns the proper extended double-precision floating-point value |
| 728 | corresponding to the abstract input. This routine is just like |
| 729 | `roundAndPackFloatx80' except that the input significand does not have to be |
| 730 | normalized. |
| 731 | ------------------------------------------------------------------------------- |
| 732 | */ |
| 733 | static floatx80 |
| 734 | normalizeRoundAndPackFloatx80( |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 735 | struct roundingData *roundData, flag zSign, int32 zExp, bits64 zSig0, bits64 zSig1 |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 736 | ) |
| 737 | { |
| 738 | int8 shiftCount; |
| 739 | |
| 740 | if ( zSig0 == 0 ) { |
| 741 | zSig0 = zSig1; |
| 742 | zSig1 = 0; |
| 743 | zExp -= 64; |
| 744 | } |
| 745 | shiftCount = countLeadingZeros64( zSig0 ); |
| 746 | shortShift128Left( zSig0, zSig1, shiftCount, &zSig0, &zSig1 ); |
| 747 | zExp -= shiftCount; |
| 748 | return |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 749 | roundAndPackFloatx80( roundData, zSign, zExp, zSig0, zSig1 ); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 750 | |
| 751 | } |
| 752 | |
| 753 | #endif |
| 754 | |
| 755 | /* |
| 756 | ------------------------------------------------------------------------------- |
| 757 | Returns the result of converting the 32-bit two's complement integer `a' to |
| 758 | the single-precision floating-point format. The conversion is performed |
| 759 | according to the IEC/IEEE Standard for Binary Floating-point Arithmetic. |
| 760 | ------------------------------------------------------------------------------- |
| 761 | */ |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 762 | float32 int32_to_float32(struct roundingData *roundData, int32 a) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 763 | { |
| 764 | flag zSign; |
| 765 | |
| 766 | if ( a == 0 ) return 0; |
| 767 | if ( a == 0x80000000 ) return packFloat32( 1, 0x9E, 0 ); |
| 768 | zSign = ( a < 0 ); |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 769 | return normalizeRoundAndPackFloat32( roundData, zSign, 0x9C, zSign ? - a : a ); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 770 | |
| 771 | } |
| 772 | |
| 773 | /* |
| 774 | ------------------------------------------------------------------------------- |
| 775 | Returns the result of converting the 32-bit two's complement integer `a' to |
| 776 | the double-precision floating-point format. The conversion is performed |
| 777 | according to the IEC/IEEE Standard for Binary Floating-point Arithmetic. |
| 778 | ------------------------------------------------------------------------------- |
| 779 | */ |
| 780 | float64 int32_to_float64( int32 a ) |
| 781 | { |
| 782 | flag aSign; |
| 783 | uint32 absA; |
| 784 | int8 shiftCount; |
| 785 | bits64 zSig; |
| 786 | |
| 787 | if ( a == 0 ) return 0; |
| 788 | aSign = ( a < 0 ); |
| 789 | absA = aSign ? - a : a; |
| 790 | shiftCount = countLeadingZeros32( absA ) + 21; |
| 791 | zSig = absA; |
| 792 | return packFloat64( aSign, 0x432 - shiftCount, zSig<<shiftCount ); |
| 793 | |
| 794 | } |
| 795 | |
| 796 | #ifdef FLOATX80 |
| 797 | |
| 798 | /* |
| 799 | ------------------------------------------------------------------------------- |
| 800 | Returns the result of converting the 32-bit two's complement integer `a' |
| 801 | to the extended double-precision floating-point format. The conversion |
| 802 | is performed according to the IEC/IEEE Standard for Binary Floating-point |
| 803 | Arithmetic. |
| 804 | ------------------------------------------------------------------------------- |
| 805 | */ |
| 806 | floatx80 int32_to_floatx80( int32 a ) |
| 807 | { |
| 808 | flag zSign; |
| 809 | uint32 absA; |
| 810 | int8 shiftCount; |
| 811 | bits64 zSig; |
| 812 | |
| 813 | if ( a == 0 ) return packFloatx80( 0, 0, 0 ); |
| 814 | zSign = ( a < 0 ); |
| 815 | absA = zSign ? - a : a; |
| 816 | shiftCount = countLeadingZeros32( absA ) + 32; |
| 817 | zSig = absA; |
| 818 | return packFloatx80( zSign, 0x403E - shiftCount, zSig<<shiftCount ); |
| 819 | |
| 820 | } |
| 821 | |
| 822 | #endif |
| 823 | |
| 824 | /* |
| 825 | ------------------------------------------------------------------------------- |
| 826 | Returns the result of converting the single-precision floating-point value |
| 827 | `a' to the 32-bit two's complement integer format. The conversion is |
| 828 | performed according to the IEC/IEEE Standard for Binary Floating-point |
| 829 | Arithmetic---which means in particular that the conversion is rounded |
| 830 | according to the current rounding mode. If `a' is a NaN, the largest |
| 831 | positive integer is returned. Otherwise, if the conversion overflows, the |
| 832 | largest integer with the same sign as `a' is returned. |
| 833 | ------------------------------------------------------------------------------- |
| 834 | */ |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 835 | int32 float32_to_int32( struct roundingData *roundData, float32 a ) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 836 | { |
| 837 | flag aSign; |
| 838 | int16 aExp, shiftCount; |
| 839 | bits32 aSig; |
| 840 | bits64 zSig; |
| 841 | |
| 842 | aSig = extractFloat32Frac( a ); |
| 843 | aExp = extractFloat32Exp( a ); |
| 844 | aSign = extractFloat32Sign( a ); |
| 845 | if ( ( aExp == 0x7FF ) && aSig ) aSign = 0; |
| 846 | if ( aExp ) aSig |= 0x00800000; |
| 847 | shiftCount = 0xAF - aExp; |
| 848 | zSig = aSig; |
| 849 | zSig <<= 32; |
| 850 | if ( 0 < shiftCount ) shift64RightJamming( zSig, shiftCount, &zSig ); |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 851 | return roundAndPackInt32( roundData, aSign, zSig ); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 852 | |
| 853 | } |
| 854 | |
| 855 | /* |
| 856 | ------------------------------------------------------------------------------- |
| 857 | Returns the result of converting the single-precision floating-point value |
| 858 | `a' to the 32-bit two's complement integer format. The conversion is |
| 859 | performed according to the IEC/IEEE Standard for Binary Floating-point |
| 860 | Arithmetic, except that the conversion is always rounded toward zero. If |
| 861 | `a' is a NaN, the largest positive integer is returned. Otherwise, if the |
| 862 | conversion overflows, the largest integer with the same sign as `a' is |
| 863 | returned. |
| 864 | ------------------------------------------------------------------------------- |
| 865 | */ |
| 866 | int32 float32_to_int32_round_to_zero( float32 a ) |
| 867 | { |
| 868 | flag aSign; |
| 869 | int16 aExp, shiftCount; |
| 870 | bits32 aSig; |
| 871 | int32 z; |
| 872 | |
| 873 | aSig = extractFloat32Frac( a ); |
| 874 | aExp = extractFloat32Exp( a ); |
| 875 | aSign = extractFloat32Sign( a ); |
| 876 | shiftCount = aExp - 0x9E; |
| 877 | if ( 0 <= shiftCount ) { |
| 878 | if ( a == 0xCF000000 ) return 0x80000000; |
| 879 | float_raise( float_flag_invalid ); |
| 880 | if ( ! aSign || ( ( aExp == 0xFF ) && aSig ) ) return 0x7FFFFFFF; |
| 881 | return 0x80000000; |
| 882 | } |
| 883 | else if ( aExp <= 0x7E ) { |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 884 | if ( aExp | aSig ) float_raise( float_flag_inexact ); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 885 | return 0; |
| 886 | } |
| 887 | aSig = ( aSig | 0x00800000 )<<8; |
| 888 | z = aSig>>( - shiftCount ); |
| 889 | if ( (bits32) ( aSig<<( shiftCount & 31 ) ) ) { |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 890 | float_raise( float_flag_inexact ); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 891 | } |
| 892 | return aSign ? - z : z; |
| 893 | |
| 894 | } |
| 895 | |
| 896 | /* |
| 897 | ------------------------------------------------------------------------------- |
| 898 | Returns the result of converting the single-precision floating-point value |
| 899 | `a' to the double-precision floating-point format. The conversion is |
| 900 | performed according to the IEC/IEEE Standard for Binary Floating-point |
| 901 | Arithmetic. |
| 902 | ------------------------------------------------------------------------------- |
| 903 | */ |
| 904 | float64 float32_to_float64( float32 a ) |
| 905 | { |
| 906 | flag aSign; |
| 907 | int16 aExp; |
| 908 | bits32 aSig; |
| 909 | |
| 910 | aSig = extractFloat32Frac( a ); |
| 911 | aExp = extractFloat32Exp( a ); |
| 912 | aSign = extractFloat32Sign( a ); |
| 913 | if ( aExp == 0xFF ) { |
| 914 | if ( aSig ) return commonNaNToFloat64( float32ToCommonNaN( a ) ); |
| 915 | return packFloat64( aSign, 0x7FF, 0 ); |
| 916 | } |
| 917 | if ( aExp == 0 ) { |
| 918 | if ( aSig == 0 ) return packFloat64( aSign, 0, 0 ); |
| 919 | normalizeFloat32Subnormal( aSig, &aExp, &aSig ); |
| 920 | --aExp; |
| 921 | } |
| 922 | return packFloat64( aSign, aExp + 0x380, ( (bits64) aSig )<<29 ); |
| 923 | |
| 924 | } |
| 925 | |
| 926 | #ifdef FLOATX80 |
| 927 | |
| 928 | /* |
| 929 | ------------------------------------------------------------------------------- |
| 930 | Returns the result of converting the single-precision floating-point value |
| 931 | `a' to the extended double-precision floating-point format. The conversion |
| 932 | is performed according to the IEC/IEEE Standard for Binary Floating-point |
| 933 | Arithmetic. |
| 934 | ------------------------------------------------------------------------------- |
| 935 | */ |
| 936 | floatx80 float32_to_floatx80( float32 a ) |
| 937 | { |
| 938 | flag aSign; |
| 939 | int16 aExp; |
| 940 | bits32 aSig; |
| 941 | |
| 942 | aSig = extractFloat32Frac( a ); |
| 943 | aExp = extractFloat32Exp( a ); |
| 944 | aSign = extractFloat32Sign( a ); |
| 945 | if ( aExp == 0xFF ) { |
| 946 | if ( aSig ) return commonNaNToFloatx80( float32ToCommonNaN( a ) ); |
| 947 | return packFloatx80( aSign, 0x7FFF, LIT64( 0x8000000000000000 ) ); |
| 948 | } |
| 949 | if ( aExp == 0 ) { |
| 950 | if ( aSig == 0 ) return packFloatx80( aSign, 0, 0 ); |
| 951 | normalizeFloat32Subnormal( aSig, &aExp, &aSig ); |
| 952 | } |
| 953 | aSig |= 0x00800000; |
| 954 | return packFloatx80( aSign, aExp + 0x3F80, ( (bits64) aSig )<<40 ); |
| 955 | |
| 956 | } |
| 957 | |
| 958 | #endif |
| 959 | |
| 960 | /* |
| 961 | ------------------------------------------------------------------------------- |
| 962 | Rounds the single-precision floating-point value `a' to an integer, and |
| 963 | returns the result as a single-precision floating-point value. The |
| 964 | operation is performed according to the IEC/IEEE Standard for Binary |
| 965 | Floating-point Arithmetic. |
| 966 | ------------------------------------------------------------------------------- |
| 967 | */ |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 968 | float32 float32_round_to_int( struct roundingData *roundData, float32 a ) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 969 | { |
| 970 | flag aSign; |
| 971 | int16 aExp; |
| 972 | bits32 lastBitMask, roundBitsMask; |
| 973 | int8 roundingMode; |
| 974 | float32 z; |
| 975 | |
| 976 | aExp = extractFloat32Exp( a ); |
| 977 | if ( 0x96 <= aExp ) { |
| 978 | if ( ( aExp == 0xFF ) && extractFloat32Frac( a ) ) { |
| 979 | return propagateFloat32NaN( a, a ); |
| 980 | } |
| 981 | return a; |
| 982 | } |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 983 | roundingMode = roundData->mode; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 984 | if ( aExp <= 0x7E ) { |
| 985 | if ( (bits32) ( a<<1 ) == 0 ) return a; |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 986 | roundData->exception |= float_flag_inexact; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 987 | aSign = extractFloat32Sign( a ); |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 988 | switch ( roundingMode ) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 989 | case float_round_nearest_even: |
| 990 | if ( ( aExp == 0x7E ) && extractFloat32Frac( a ) ) { |
| 991 | return packFloat32( aSign, 0x7F, 0 ); |
| 992 | } |
| 993 | break; |
| 994 | case float_round_down: |
| 995 | return aSign ? 0xBF800000 : 0; |
| 996 | case float_round_up: |
| 997 | return aSign ? 0x80000000 : 0x3F800000; |
| 998 | } |
| 999 | return packFloat32( aSign, 0, 0 ); |
| 1000 | } |
| 1001 | lastBitMask = 1; |
| 1002 | lastBitMask <<= 0x96 - aExp; |
| 1003 | roundBitsMask = lastBitMask - 1; |
| 1004 | z = a; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1005 | if ( roundingMode == float_round_nearest_even ) { |
| 1006 | z += lastBitMask>>1; |
| 1007 | if ( ( z & roundBitsMask ) == 0 ) z &= ~ lastBitMask; |
| 1008 | } |
| 1009 | else if ( roundingMode != float_round_to_zero ) { |
| 1010 | if ( extractFloat32Sign( z ) ^ ( roundingMode == float_round_up ) ) { |
| 1011 | z += roundBitsMask; |
| 1012 | } |
| 1013 | } |
| 1014 | z &= ~ roundBitsMask; |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 1015 | if ( z != a ) roundData->exception |= float_flag_inexact; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1016 | return z; |
| 1017 | |
| 1018 | } |
| 1019 | |
| 1020 | /* |
| 1021 | ------------------------------------------------------------------------------- |
| 1022 | Returns the result of adding the absolute values of the single-precision |
| 1023 | floating-point values `a' and `b'. If `zSign' is true, the sum is negated |
| 1024 | before being returned. `zSign' is ignored if the result is a NaN. The |
| 1025 | addition is performed according to the IEC/IEEE Standard for Binary |
| 1026 | Floating-point Arithmetic. |
| 1027 | ------------------------------------------------------------------------------- |
| 1028 | */ |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 1029 | static float32 addFloat32Sigs( struct roundingData *roundData, float32 a, float32 b, flag zSign ) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1030 | { |
| 1031 | int16 aExp, bExp, zExp; |
| 1032 | bits32 aSig, bSig, zSig; |
| 1033 | int16 expDiff; |
| 1034 | |
| 1035 | aSig = extractFloat32Frac( a ); |
| 1036 | aExp = extractFloat32Exp( a ); |
| 1037 | bSig = extractFloat32Frac( b ); |
| 1038 | bExp = extractFloat32Exp( b ); |
| 1039 | expDiff = aExp - bExp; |
| 1040 | aSig <<= 6; |
| 1041 | bSig <<= 6; |
| 1042 | if ( 0 < expDiff ) { |
| 1043 | if ( aExp == 0xFF ) { |
| 1044 | if ( aSig ) return propagateFloat32NaN( a, b ); |
| 1045 | return a; |
| 1046 | } |
| 1047 | if ( bExp == 0 ) { |
| 1048 | --expDiff; |
| 1049 | } |
| 1050 | else { |
| 1051 | bSig |= 0x20000000; |
| 1052 | } |
| 1053 | shift32RightJamming( bSig, expDiff, &bSig ); |
| 1054 | zExp = aExp; |
| 1055 | } |
| 1056 | else if ( expDiff < 0 ) { |
| 1057 | if ( bExp == 0xFF ) { |
| 1058 | if ( bSig ) return propagateFloat32NaN( a, b ); |
| 1059 | return packFloat32( zSign, 0xFF, 0 ); |
| 1060 | } |
| 1061 | if ( aExp == 0 ) { |
| 1062 | ++expDiff; |
| 1063 | } |
| 1064 | else { |
| 1065 | aSig |= 0x20000000; |
| 1066 | } |
| 1067 | shift32RightJamming( aSig, - expDiff, &aSig ); |
| 1068 | zExp = bExp; |
| 1069 | } |
| 1070 | else { |
| 1071 | if ( aExp == 0xFF ) { |
| 1072 | if ( aSig | bSig ) return propagateFloat32NaN( a, b ); |
| 1073 | return a; |
| 1074 | } |
| 1075 | if ( aExp == 0 ) return packFloat32( zSign, 0, ( aSig + bSig )>>6 ); |
| 1076 | zSig = 0x40000000 + aSig + bSig; |
| 1077 | zExp = aExp; |
| 1078 | goto roundAndPack; |
| 1079 | } |
| 1080 | aSig |= 0x20000000; |
| 1081 | zSig = ( aSig + bSig )<<1; |
| 1082 | --zExp; |
| 1083 | if ( (sbits32) zSig < 0 ) { |
| 1084 | zSig = aSig + bSig; |
| 1085 | ++zExp; |
| 1086 | } |
| 1087 | roundAndPack: |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 1088 | return roundAndPackFloat32( roundData, zSign, zExp, zSig ); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1089 | |
| 1090 | } |
| 1091 | |
| 1092 | /* |
| 1093 | ------------------------------------------------------------------------------- |
| 1094 | Returns the result of subtracting the absolute values of the single- |
| 1095 | precision floating-point values `a' and `b'. If `zSign' is true, the |
| 1096 | difference is negated before being returned. `zSign' is ignored if the |
| 1097 | result is a NaN. The subtraction is performed according to the IEC/IEEE |
| 1098 | Standard for Binary Floating-point Arithmetic. |
| 1099 | ------------------------------------------------------------------------------- |
| 1100 | */ |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 1101 | static float32 subFloat32Sigs( struct roundingData *roundData, float32 a, float32 b, flag zSign ) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1102 | { |
| 1103 | int16 aExp, bExp, zExp; |
| 1104 | bits32 aSig, bSig, zSig; |
| 1105 | int16 expDiff; |
| 1106 | |
| 1107 | aSig = extractFloat32Frac( a ); |
| 1108 | aExp = extractFloat32Exp( a ); |
| 1109 | bSig = extractFloat32Frac( b ); |
| 1110 | bExp = extractFloat32Exp( b ); |
| 1111 | expDiff = aExp - bExp; |
| 1112 | aSig <<= 7; |
| 1113 | bSig <<= 7; |
| 1114 | if ( 0 < expDiff ) goto aExpBigger; |
| 1115 | if ( expDiff < 0 ) goto bExpBigger; |
| 1116 | if ( aExp == 0xFF ) { |
| 1117 | if ( aSig | bSig ) return propagateFloat32NaN( a, b ); |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 1118 | roundData->exception |= float_flag_invalid; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1119 | return float32_default_nan; |
| 1120 | } |
| 1121 | if ( aExp == 0 ) { |
| 1122 | aExp = 1; |
| 1123 | bExp = 1; |
| 1124 | } |
| 1125 | if ( bSig < aSig ) goto aBigger; |
| 1126 | if ( aSig < bSig ) goto bBigger; |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 1127 | return packFloat32( roundData->mode == float_round_down, 0, 0 ); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1128 | bExpBigger: |
| 1129 | if ( bExp == 0xFF ) { |
| 1130 | if ( bSig ) return propagateFloat32NaN( a, b ); |
| 1131 | return packFloat32( zSign ^ 1, 0xFF, 0 ); |
| 1132 | } |
| 1133 | if ( aExp == 0 ) { |
| 1134 | ++expDiff; |
| 1135 | } |
| 1136 | else { |
| 1137 | aSig |= 0x40000000; |
| 1138 | } |
| 1139 | shift32RightJamming( aSig, - expDiff, &aSig ); |
| 1140 | bSig |= 0x40000000; |
| 1141 | bBigger: |
| 1142 | zSig = bSig - aSig; |
| 1143 | zExp = bExp; |
| 1144 | zSign ^= 1; |
| 1145 | goto normalizeRoundAndPack; |
| 1146 | aExpBigger: |
| 1147 | if ( aExp == 0xFF ) { |
| 1148 | if ( aSig ) return propagateFloat32NaN( a, b ); |
| 1149 | return a; |
| 1150 | } |
| 1151 | if ( bExp == 0 ) { |
| 1152 | --expDiff; |
| 1153 | } |
| 1154 | else { |
| 1155 | bSig |= 0x40000000; |
| 1156 | } |
| 1157 | shift32RightJamming( bSig, expDiff, &bSig ); |
| 1158 | aSig |= 0x40000000; |
| 1159 | aBigger: |
| 1160 | zSig = aSig - bSig; |
| 1161 | zExp = aExp; |
| 1162 | normalizeRoundAndPack: |
| 1163 | --zExp; |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 1164 | return normalizeRoundAndPackFloat32( roundData, zSign, zExp, zSig ); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1165 | |
| 1166 | } |
| 1167 | |
| 1168 | /* |
| 1169 | ------------------------------------------------------------------------------- |
| 1170 | Returns the result of adding the single-precision floating-point values `a' |
| 1171 | and `b'. The operation is performed according to the IEC/IEEE Standard for |
| 1172 | Binary Floating-point Arithmetic. |
| 1173 | ------------------------------------------------------------------------------- |
| 1174 | */ |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 1175 | float32 float32_add( struct roundingData *roundData, float32 a, float32 b ) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1176 | { |
| 1177 | flag aSign, bSign; |
| 1178 | |
| 1179 | aSign = extractFloat32Sign( a ); |
| 1180 | bSign = extractFloat32Sign( b ); |
| 1181 | if ( aSign == bSign ) { |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 1182 | return addFloat32Sigs( roundData, a, b, aSign ); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1183 | } |
| 1184 | else { |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 1185 | return subFloat32Sigs( roundData, a, b, aSign ); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1186 | } |
| 1187 | |
| 1188 | } |
| 1189 | |
| 1190 | /* |
| 1191 | ------------------------------------------------------------------------------- |
| 1192 | Returns the result of subtracting the single-precision floating-point values |
| 1193 | `a' and `b'. The operation is performed according to the IEC/IEEE Standard |
| 1194 | for Binary Floating-point Arithmetic. |
| 1195 | ------------------------------------------------------------------------------- |
| 1196 | */ |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 1197 | float32 float32_sub( struct roundingData *roundData, float32 a, float32 b ) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1198 | { |
| 1199 | flag aSign, bSign; |
| 1200 | |
| 1201 | aSign = extractFloat32Sign( a ); |
| 1202 | bSign = extractFloat32Sign( b ); |
| 1203 | if ( aSign == bSign ) { |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 1204 | return subFloat32Sigs( roundData, a, b, aSign ); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1205 | } |
| 1206 | else { |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 1207 | return addFloat32Sigs( roundData, a, b, aSign ); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1208 | } |
| 1209 | |
| 1210 | } |
| 1211 | |
| 1212 | /* |
| 1213 | ------------------------------------------------------------------------------- |
| 1214 | Returns the result of multiplying the single-precision floating-point values |
| 1215 | `a' and `b'. The operation is performed according to the IEC/IEEE Standard |
| 1216 | for Binary Floating-point Arithmetic. |
| 1217 | ------------------------------------------------------------------------------- |
| 1218 | */ |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 1219 | float32 float32_mul( struct roundingData *roundData, float32 a, float32 b ) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1220 | { |
| 1221 | flag aSign, bSign, zSign; |
| 1222 | int16 aExp, bExp, zExp; |
| 1223 | bits32 aSig, bSig; |
| 1224 | bits64 zSig64; |
| 1225 | bits32 zSig; |
| 1226 | |
| 1227 | aSig = extractFloat32Frac( a ); |
| 1228 | aExp = extractFloat32Exp( a ); |
| 1229 | aSign = extractFloat32Sign( a ); |
| 1230 | bSig = extractFloat32Frac( b ); |
| 1231 | bExp = extractFloat32Exp( b ); |
| 1232 | bSign = extractFloat32Sign( b ); |
| 1233 | zSign = aSign ^ bSign; |
| 1234 | if ( aExp == 0xFF ) { |
| 1235 | if ( aSig || ( ( bExp == 0xFF ) && bSig ) ) { |
| 1236 | return propagateFloat32NaN( a, b ); |
| 1237 | } |
| 1238 | if ( ( bExp | bSig ) == 0 ) { |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 1239 | roundData->exception |= float_flag_invalid; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1240 | return float32_default_nan; |
| 1241 | } |
| 1242 | return packFloat32( zSign, 0xFF, 0 ); |
| 1243 | } |
| 1244 | if ( bExp == 0xFF ) { |
| 1245 | if ( bSig ) return propagateFloat32NaN( a, b ); |
| 1246 | if ( ( aExp | aSig ) == 0 ) { |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 1247 | roundData->exception |= float_flag_invalid; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1248 | return float32_default_nan; |
| 1249 | } |
| 1250 | return packFloat32( zSign, 0xFF, 0 ); |
| 1251 | } |
| 1252 | if ( aExp == 0 ) { |
| 1253 | if ( aSig == 0 ) return packFloat32( zSign, 0, 0 ); |
| 1254 | normalizeFloat32Subnormal( aSig, &aExp, &aSig ); |
| 1255 | } |
| 1256 | if ( bExp == 0 ) { |
| 1257 | if ( bSig == 0 ) return packFloat32( zSign, 0, 0 ); |
| 1258 | normalizeFloat32Subnormal( bSig, &bExp, &bSig ); |
| 1259 | } |
| 1260 | zExp = aExp + bExp - 0x7F; |
| 1261 | aSig = ( aSig | 0x00800000 )<<7; |
| 1262 | bSig = ( bSig | 0x00800000 )<<8; |
| 1263 | shift64RightJamming( ( (bits64) aSig ) * bSig, 32, &zSig64 ); |
| 1264 | zSig = zSig64; |
| 1265 | if ( 0 <= (sbits32) ( zSig<<1 ) ) { |
| 1266 | zSig <<= 1; |
| 1267 | --zExp; |
| 1268 | } |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 1269 | return roundAndPackFloat32( roundData, zSign, zExp, zSig ); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1270 | |
| 1271 | } |
| 1272 | |
| 1273 | /* |
| 1274 | ------------------------------------------------------------------------------- |
| 1275 | Returns the result of dividing the single-precision floating-point value `a' |
| 1276 | by the corresponding value `b'. The operation is performed according to the |
| 1277 | IEC/IEEE Standard for Binary Floating-point Arithmetic. |
| 1278 | ------------------------------------------------------------------------------- |
| 1279 | */ |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 1280 | float32 float32_div( struct roundingData *roundData, float32 a, float32 b ) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1281 | { |
| 1282 | flag aSign, bSign, zSign; |
| 1283 | int16 aExp, bExp, zExp; |
| 1284 | bits32 aSig, bSig, zSig; |
| 1285 | |
| 1286 | aSig = extractFloat32Frac( a ); |
| 1287 | aExp = extractFloat32Exp( a ); |
| 1288 | aSign = extractFloat32Sign( a ); |
| 1289 | bSig = extractFloat32Frac( b ); |
| 1290 | bExp = extractFloat32Exp( b ); |
| 1291 | bSign = extractFloat32Sign( b ); |
| 1292 | zSign = aSign ^ bSign; |
| 1293 | if ( aExp == 0xFF ) { |
| 1294 | if ( aSig ) return propagateFloat32NaN( a, b ); |
| 1295 | if ( bExp == 0xFF ) { |
| 1296 | if ( bSig ) return propagateFloat32NaN( a, b ); |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 1297 | roundData->exception |= float_flag_invalid; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1298 | return float32_default_nan; |
| 1299 | } |
| 1300 | return packFloat32( zSign, 0xFF, 0 ); |
| 1301 | } |
| 1302 | if ( bExp == 0xFF ) { |
| 1303 | if ( bSig ) return propagateFloat32NaN( a, b ); |
| 1304 | return packFloat32( zSign, 0, 0 ); |
| 1305 | } |
| 1306 | if ( bExp == 0 ) { |
| 1307 | if ( bSig == 0 ) { |
| 1308 | if ( ( aExp | aSig ) == 0 ) { |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 1309 | roundData->exception |= float_flag_invalid; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1310 | return float32_default_nan; |
| 1311 | } |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 1312 | roundData->exception |= float_flag_divbyzero; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1313 | return packFloat32( zSign, 0xFF, 0 ); |
| 1314 | } |
| 1315 | normalizeFloat32Subnormal( bSig, &bExp, &bSig ); |
| 1316 | } |
| 1317 | if ( aExp == 0 ) { |
| 1318 | if ( aSig == 0 ) return packFloat32( zSign, 0, 0 ); |
| 1319 | normalizeFloat32Subnormal( aSig, &aExp, &aSig ); |
| 1320 | } |
| 1321 | zExp = aExp - bExp + 0x7D; |
| 1322 | aSig = ( aSig | 0x00800000 )<<7; |
| 1323 | bSig = ( bSig | 0x00800000 )<<8; |
| 1324 | if ( bSig <= ( aSig + aSig ) ) { |
| 1325 | aSig >>= 1; |
| 1326 | ++zExp; |
| 1327 | } |
Nicolas Pitre | c1241c4c | 2005-06-23 21:56:46 +0100 | [diff] [blame] | 1328 | { |
| 1329 | bits64 tmp = ( (bits64) aSig )<<32; |
| 1330 | do_div( tmp, bSig ); |
| 1331 | zSig = tmp; |
| 1332 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1333 | if ( ( zSig & 0x3F ) == 0 ) { |
| 1334 | zSig |= ( ( (bits64) bSig ) * zSig != ( (bits64) aSig )<<32 ); |
| 1335 | } |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 1336 | return roundAndPackFloat32( roundData, zSign, zExp, zSig ); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1337 | |
| 1338 | } |
| 1339 | |
| 1340 | /* |
| 1341 | ------------------------------------------------------------------------------- |
| 1342 | Returns the remainder of the single-precision floating-point value `a' |
| 1343 | with respect to the corresponding value `b'. The operation is performed |
| 1344 | according to the IEC/IEEE Standard for Binary Floating-point Arithmetic. |
| 1345 | ------------------------------------------------------------------------------- |
| 1346 | */ |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 1347 | float32 float32_rem( struct roundingData *roundData, float32 a, float32 b ) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1348 | { |
| 1349 | flag aSign, bSign, zSign; |
| 1350 | int16 aExp, bExp, expDiff; |
| 1351 | bits32 aSig, bSig; |
| 1352 | bits32 q; |
| 1353 | bits64 aSig64, bSig64, q64; |
| 1354 | bits32 alternateASig; |
| 1355 | sbits32 sigMean; |
| 1356 | |
| 1357 | aSig = extractFloat32Frac( a ); |
| 1358 | aExp = extractFloat32Exp( a ); |
| 1359 | aSign = extractFloat32Sign( a ); |
| 1360 | bSig = extractFloat32Frac( b ); |
| 1361 | bExp = extractFloat32Exp( b ); |
| 1362 | bSign = extractFloat32Sign( b ); |
| 1363 | if ( aExp == 0xFF ) { |
| 1364 | if ( aSig || ( ( bExp == 0xFF ) && bSig ) ) { |
| 1365 | return propagateFloat32NaN( a, b ); |
| 1366 | } |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 1367 | roundData->exception |= float_flag_invalid; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1368 | return float32_default_nan; |
| 1369 | } |
| 1370 | if ( bExp == 0xFF ) { |
| 1371 | if ( bSig ) return propagateFloat32NaN( a, b ); |
| 1372 | return a; |
| 1373 | } |
| 1374 | if ( bExp == 0 ) { |
| 1375 | if ( bSig == 0 ) { |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 1376 | roundData->exception |= float_flag_invalid; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1377 | return float32_default_nan; |
| 1378 | } |
| 1379 | normalizeFloat32Subnormal( bSig, &bExp, &bSig ); |
| 1380 | } |
| 1381 | if ( aExp == 0 ) { |
| 1382 | if ( aSig == 0 ) return a; |
| 1383 | normalizeFloat32Subnormal( aSig, &aExp, &aSig ); |
| 1384 | } |
| 1385 | expDiff = aExp - bExp; |
| 1386 | aSig |= 0x00800000; |
| 1387 | bSig |= 0x00800000; |
| 1388 | if ( expDiff < 32 ) { |
| 1389 | aSig <<= 8; |
| 1390 | bSig <<= 8; |
| 1391 | if ( expDiff < 0 ) { |
| 1392 | if ( expDiff < -1 ) return a; |
| 1393 | aSig >>= 1; |
| 1394 | } |
| 1395 | q = ( bSig <= aSig ); |
| 1396 | if ( q ) aSig -= bSig; |
| 1397 | if ( 0 < expDiff ) { |
Nicolas Pitre | c1241c4c | 2005-06-23 21:56:46 +0100 | [diff] [blame] | 1398 | bits64 tmp = ( (bits64) aSig )<<32; |
| 1399 | do_div( tmp, bSig ); |
| 1400 | q = tmp; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1401 | q >>= 32 - expDiff; |
| 1402 | bSig >>= 2; |
| 1403 | aSig = ( ( aSig>>1 )<<( expDiff - 1 ) ) - bSig * q; |
| 1404 | } |
| 1405 | else { |
| 1406 | aSig >>= 2; |
| 1407 | bSig >>= 2; |
| 1408 | } |
| 1409 | } |
| 1410 | else { |
| 1411 | if ( bSig <= aSig ) aSig -= bSig; |
| 1412 | aSig64 = ( (bits64) aSig )<<40; |
| 1413 | bSig64 = ( (bits64) bSig )<<40; |
| 1414 | expDiff -= 64; |
| 1415 | while ( 0 < expDiff ) { |
| 1416 | q64 = estimateDiv128To64( aSig64, 0, bSig64 ); |
| 1417 | q64 = ( 2 < q64 ) ? q64 - 2 : 0; |
| 1418 | aSig64 = - ( ( bSig * q64 )<<38 ); |
| 1419 | expDiff -= 62; |
| 1420 | } |
| 1421 | expDiff += 64; |
| 1422 | q64 = estimateDiv128To64( aSig64, 0, bSig64 ); |
| 1423 | q64 = ( 2 < q64 ) ? q64 - 2 : 0; |
| 1424 | q = q64>>( 64 - expDiff ); |
| 1425 | bSig <<= 6; |
| 1426 | aSig = ( ( aSig64>>33 )<<( expDiff - 1 ) ) - bSig * q; |
| 1427 | } |
| 1428 | do { |
| 1429 | alternateASig = aSig; |
| 1430 | ++q; |
| 1431 | aSig -= bSig; |
| 1432 | } while ( 0 <= (sbits32) aSig ); |
| 1433 | sigMean = aSig + alternateASig; |
| 1434 | if ( ( sigMean < 0 ) || ( ( sigMean == 0 ) && ( q & 1 ) ) ) { |
| 1435 | aSig = alternateASig; |
| 1436 | } |
| 1437 | zSign = ( (sbits32) aSig < 0 ); |
| 1438 | if ( zSign ) aSig = - aSig; |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 1439 | return normalizeRoundAndPackFloat32( roundData, aSign ^ zSign, bExp, aSig ); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1440 | |
| 1441 | } |
| 1442 | |
| 1443 | /* |
| 1444 | ------------------------------------------------------------------------------- |
| 1445 | Returns the square root of the single-precision floating-point value `a'. |
| 1446 | The operation is performed according to the IEC/IEEE Standard for Binary |
| 1447 | Floating-point Arithmetic. |
| 1448 | ------------------------------------------------------------------------------- |
| 1449 | */ |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 1450 | float32 float32_sqrt( struct roundingData *roundData, float32 a ) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1451 | { |
| 1452 | flag aSign; |
| 1453 | int16 aExp, zExp; |
| 1454 | bits32 aSig, zSig; |
| 1455 | bits64 rem, term; |
| 1456 | |
| 1457 | aSig = extractFloat32Frac( a ); |
| 1458 | aExp = extractFloat32Exp( a ); |
| 1459 | aSign = extractFloat32Sign( a ); |
| 1460 | if ( aExp == 0xFF ) { |
| 1461 | if ( aSig ) return propagateFloat32NaN( a, 0 ); |
| 1462 | if ( ! aSign ) return a; |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 1463 | roundData->exception |= float_flag_invalid; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1464 | return float32_default_nan; |
| 1465 | } |
| 1466 | if ( aSign ) { |
| 1467 | if ( ( aExp | aSig ) == 0 ) return a; |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 1468 | roundData->exception |= float_flag_invalid; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1469 | return float32_default_nan; |
| 1470 | } |
| 1471 | if ( aExp == 0 ) { |
| 1472 | if ( aSig == 0 ) return 0; |
| 1473 | normalizeFloat32Subnormal( aSig, &aExp, &aSig ); |
| 1474 | } |
| 1475 | zExp = ( ( aExp - 0x7F )>>1 ) + 0x7E; |
| 1476 | aSig = ( aSig | 0x00800000 )<<8; |
| 1477 | zSig = estimateSqrt32( aExp, aSig ) + 2; |
| 1478 | if ( ( zSig & 0x7F ) <= 5 ) { |
| 1479 | if ( zSig < 2 ) { |
| 1480 | zSig = 0xFFFFFFFF; |
| 1481 | } |
| 1482 | else { |
| 1483 | aSig >>= aExp & 1; |
| 1484 | term = ( (bits64) zSig ) * zSig; |
| 1485 | rem = ( ( (bits64) aSig )<<32 ) - term; |
| 1486 | while ( (sbits64) rem < 0 ) { |
| 1487 | --zSig; |
| 1488 | rem += ( ( (bits64) zSig )<<1 ) | 1; |
| 1489 | } |
| 1490 | zSig |= ( rem != 0 ); |
| 1491 | } |
| 1492 | } |
| 1493 | shift32RightJamming( zSig, 1, &zSig ); |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 1494 | return roundAndPackFloat32( roundData, 0, zExp, zSig ); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1495 | |
| 1496 | } |
| 1497 | |
| 1498 | /* |
| 1499 | ------------------------------------------------------------------------------- |
| 1500 | Returns 1 if the single-precision floating-point value `a' is equal to the |
| 1501 | corresponding value `b', and 0 otherwise. The comparison is performed |
| 1502 | according to the IEC/IEEE Standard for Binary Floating-point Arithmetic. |
| 1503 | ------------------------------------------------------------------------------- |
| 1504 | */ |
| 1505 | flag float32_eq( float32 a, float32 b ) |
| 1506 | { |
| 1507 | |
| 1508 | if ( ( ( extractFloat32Exp( a ) == 0xFF ) && extractFloat32Frac( a ) ) |
| 1509 | || ( ( extractFloat32Exp( b ) == 0xFF ) && extractFloat32Frac( b ) ) |
| 1510 | ) { |
| 1511 | if ( float32_is_signaling_nan( a ) || float32_is_signaling_nan( b ) ) { |
| 1512 | float_raise( float_flag_invalid ); |
| 1513 | } |
| 1514 | return 0; |
| 1515 | } |
| 1516 | return ( a == b ) || ( (bits32) ( ( a | b )<<1 ) == 0 ); |
| 1517 | |
| 1518 | } |
| 1519 | |
| 1520 | /* |
| 1521 | ------------------------------------------------------------------------------- |
| 1522 | Returns 1 if the single-precision floating-point value `a' is less than or |
| 1523 | equal to the corresponding value `b', and 0 otherwise. The comparison is |
| 1524 | performed according to the IEC/IEEE Standard for Binary Floating-point |
| 1525 | Arithmetic. |
| 1526 | ------------------------------------------------------------------------------- |
| 1527 | */ |
| 1528 | flag float32_le( float32 a, float32 b ) |
| 1529 | { |
| 1530 | flag aSign, bSign; |
| 1531 | |
| 1532 | if ( ( ( extractFloat32Exp( a ) == 0xFF ) && extractFloat32Frac( a ) ) |
| 1533 | || ( ( extractFloat32Exp( b ) == 0xFF ) && extractFloat32Frac( b ) ) |
| 1534 | ) { |
| 1535 | float_raise( float_flag_invalid ); |
| 1536 | return 0; |
| 1537 | } |
| 1538 | aSign = extractFloat32Sign( a ); |
| 1539 | bSign = extractFloat32Sign( b ); |
| 1540 | if ( aSign != bSign ) return aSign || ( (bits32) ( ( a | b )<<1 ) == 0 ); |
| 1541 | return ( a == b ) || ( aSign ^ ( a < b ) ); |
| 1542 | |
| 1543 | } |
| 1544 | |
| 1545 | /* |
| 1546 | ------------------------------------------------------------------------------- |
| 1547 | Returns 1 if the single-precision floating-point value `a' is less than |
| 1548 | the corresponding value `b', and 0 otherwise. The comparison is performed |
| 1549 | according to the IEC/IEEE Standard for Binary Floating-point Arithmetic. |
| 1550 | ------------------------------------------------------------------------------- |
| 1551 | */ |
| 1552 | flag float32_lt( float32 a, float32 b ) |
| 1553 | { |
| 1554 | flag aSign, bSign; |
| 1555 | |
| 1556 | if ( ( ( extractFloat32Exp( a ) == 0xFF ) && extractFloat32Frac( a ) ) |
| 1557 | || ( ( extractFloat32Exp( b ) == 0xFF ) && extractFloat32Frac( b ) ) |
| 1558 | ) { |
| 1559 | float_raise( float_flag_invalid ); |
| 1560 | return 0; |
| 1561 | } |
| 1562 | aSign = extractFloat32Sign( a ); |
| 1563 | bSign = extractFloat32Sign( b ); |
| 1564 | if ( aSign != bSign ) return aSign && ( (bits32) ( ( a | b )<<1 ) != 0 ); |
| 1565 | return ( a != b ) && ( aSign ^ ( a < b ) ); |
| 1566 | |
| 1567 | } |
| 1568 | |
| 1569 | /* |
| 1570 | ------------------------------------------------------------------------------- |
| 1571 | Returns 1 if the single-precision floating-point value `a' is equal to the |
| 1572 | corresponding value `b', and 0 otherwise. The invalid exception is raised |
| 1573 | if either operand is a NaN. Otherwise, the comparison is performed |
| 1574 | according to the IEC/IEEE Standard for Binary Floating-point Arithmetic. |
| 1575 | ------------------------------------------------------------------------------- |
| 1576 | */ |
| 1577 | flag float32_eq_signaling( float32 a, float32 b ) |
| 1578 | { |
| 1579 | |
| 1580 | if ( ( ( extractFloat32Exp( a ) == 0xFF ) && extractFloat32Frac( a ) ) |
| 1581 | || ( ( extractFloat32Exp( b ) == 0xFF ) && extractFloat32Frac( b ) ) |
| 1582 | ) { |
| 1583 | float_raise( float_flag_invalid ); |
| 1584 | return 0; |
| 1585 | } |
| 1586 | return ( a == b ) || ( (bits32) ( ( a | b )<<1 ) == 0 ); |
| 1587 | |
| 1588 | } |
| 1589 | |
| 1590 | /* |
| 1591 | ------------------------------------------------------------------------------- |
| 1592 | Returns 1 if the single-precision floating-point value `a' is less than or |
| 1593 | equal to the corresponding value `b', and 0 otherwise. Quiet NaNs do not |
| 1594 | cause an exception. Otherwise, the comparison is performed according to the |
| 1595 | IEC/IEEE Standard for Binary Floating-point Arithmetic. |
| 1596 | ------------------------------------------------------------------------------- |
| 1597 | */ |
| 1598 | flag float32_le_quiet( float32 a, float32 b ) |
| 1599 | { |
| 1600 | flag aSign, bSign; |
| 1601 | //int16 aExp, bExp; |
| 1602 | |
| 1603 | if ( ( ( extractFloat32Exp( a ) == 0xFF ) && extractFloat32Frac( a ) ) |
| 1604 | || ( ( extractFloat32Exp( b ) == 0xFF ) && extractFloat32Frac( b ) ) |
| 1605 | ) { |
Richard Purdie | 54738e8 | 2005-08-15 20:42:32 +0100 | [diff] [blame] | 1606 | /* Do nothing, even if NaN as we're quiet */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1607 | return 0; |
| 1608 | } |
| 1609 | aSign = extractFloat32Sign( a ); |
| 1610 | bSign = extractFloat32Sign( b ); |
| 1611 | if ( aSign != bSign ) return aSign || ( (bits32) ( ( a | b )<<1 ) == 0 ); |
| 1612 | return ( a == b ) || ( aSign ^ ( a < b ) ); |
| 1613 | |
| 1614 | } |
| 1615 | |
| 1616 | /* |
| 1617 | ------------------------------------------------------------------------------- |
| 1618 | Returns 1 if the single-precision floating-point value `a' is less than |
| 1619 | the corresponding value `b', and 0 otherwise. Quiet NaNs do not cause an |
| 1620 | exception. Otherwise, the comparison is performed according to the IEC/IEEE |
| 1621 | Standard for Binary Floating-point Arithmetic. |
| 1622 | ------------------------------------------------------------------------------- |
| 1623 | */ |
| 1624 | flag float32_lt_quiet( float32 a, float32 b ) |
| 1625 | { |
| 1626 | flag aSign, bSign; |
| 1627 | |
| 1628 | if ( ( ( extractFloat32Exp( a ) == 0xFF ) && extractFloat32Frac( a ) ) |
| 1629 | || ( ( extractFloat32Exp( b ) == 0xFF ) && extractFloat32Frac( b ) ) |
| 1630 | ) { |
Richard Purdie | 54738e8 | 2005-08-15 20:42:32 +0100 | [diff] [blame] | 1631 | /* Do nothing, even if NaN as we're quiet */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1632 | return 0; |
| 1633 | } |
| 1634 | aSign = extractFloat32Sign( a ); |
| 1635 | bSign = extractFloat32Sign( b ); |
| 1636 | if ( aSign != bSign ) return aSign && ( (bits32) ( ( a | b )<<1 ) != 0 ); |
| 1637 | return ( a != b ) && ( aSign ^ ( a < b ) ); |
| 1638 | |
| 1639 | } |
| 1640 | |
| 1641 | /* |
| 1642 | ------------------------------------------------------------------------------- |
| 1643 | Returns the result of converting the double-precision floating-point value |
| 1644 | `a' to the 32-bit two's complement integer format. The conversion is |
| 1645 | performed according to the IEC/IEEE Standard for Binary Floating-point |
| 1646 | Arithmetic---which means in particular that the conversion is rounded |
| 1647 | according to the current rounding mode. If `a' is a NaN, the largest |
| 1648 | positive integer is returned. Otherwise, if the conversion overflows, the |
| 1649 | largest integer with the same sign as `a' is returned. |
| 1650 | ------------------------------------------------------------------------------- |
| 1651 | */ |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 1652 | int32 float64_to_int32( struct roundingData *roundData, float64 a ) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1653 | { |
| 1654 | flag aSign; |
| 1655 | int16 aExp, shiftCount; |
| 1656 | bits64 aSig; |
| 1657 | |
| 1658 | aSig = extractFloat64Frac( a ); |
| 1659 | aExp = extractFloat64Exp( a ); |
| 1660 | aSign = extractFloat64Sign( a ); |
| 1661 | if ( ( aExp == 0x7FF ) && aSig ) aSign = 0; |
| 1662 | if ( aExp ) aSig |= LIT64( 0x0010000000000000 ); |
| 1663 | shiftCount = 0x42C - aExp; |
| 1664 | if ( 0 < shiftCount ) shift64RightJamming( aSig, shiftCount, &aSig ); |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 1665 | return roundAndPackInt32( roundData, aSign, aSig ); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1666 | |
| 1667 | } |
| 1668 | |
| 1669 | /* |
| 1670 | ------------------------------------------------------------------------------- |
| 1671 | Returns the result of converting the double-precision floating-point value |
| 1672 | `a' to the 32-bit two's complement integer format. The conversion is |
| 1673 | performed according to the IEC/IEEE Standard for Binary Floating-point |
| 1674 | Arithmetic, except that the conversion is always rounded toward zero. If |
| 1675 | `a' is a NaN, the largest positive integer is returned. Otherwise, if the |
| 1676 | conversion overflows, the largest integer with the same sign as `a' is |
| 1677 | returned. |
| 1678 | ------------------------------------------------------------------------------- |
| 1679 | */ |
| 1680 | int32 float64_to_int32_round_to_zero( float64 a ) |
| 1681 | { |
| 1682 | flag aSign; |
| 1683 | int16 aExp, shiftCount; |
| 1684 | bits64 aSig, savedASig; |
| 1685 | int32 z; |
| 1686 | |
| 1687 | aSig = extractFloat64Frac( a ); |
| 1688 | aExp = extractFloat64Exp( a ); |
| 1689 | aSign = extractFloat64Sign( a ); |
| 1690 | shiftCount = 0x433 - aExp; |
| 1691 | if ( shiftCount < 21 ) { |
| 1692 | if ( ( aExp == 0x7FF ) && aSig ) aSign = 0; |
| 1693 | goto invalid; |
| 1694 | } |
| 1695 | else if ( 52 < shiftCount ) { |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 1696 | if ( aExp || aSig ) float_raise( float_flag_inexact ); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1697 | return 0; |
| 1698 | } |
| 1699 | aSig |= LIT64( 0x0010000000000000 ); |
| 1700 | savedASig = aSig; |
| 1701 | aSig >>= shiftCount; |
| 1702 | z = aSig; |
| 1703 | if ( aSign ) z = - z; |
| 1704 | if ( ( z < 0 ) ^ aSign ) { |
| 1705 | invalid: |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 1706 | float_raise( float_flag_invalid ); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1707 | return aSign ? 0x80000000 : 0x7FFFFFFF; |
| 1708 | } |
| 1709 | if ( ( aSig<<shiftCount ) != savedASig ) { |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 1710 | float_raise( float_flag_inexact ); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1711 | } |
| 1712 | return z; |
| 1713 | |
| 1714 | } |
| 1715 | |
| 1716 | /* |
| 1717 | ------------------------------------------------------------------------------- |
| 1718 | Returns the result of converting the double-precision floating-point value |
| 1719 | `a' to the 32-bit two's complement unsigned integer format. The conversion |
| 1720 | is performed according to the IEC/IEEE Standard for Binary Floating-point |
| 1721 | Arithmetic---which means in particular that the conversion is rounded |
| 1722 | according to the current rounding mode. If `a' is a NaN, the largest |
| 1723 | positive integer is returned. Otherwise, if the conversion overflows, the |
| 1724 | largest positive integer is returned. |
| 1725 | ------------------------------------------------------------------------------- |
| 1726 | */ |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 1727 | int32 float64_to_uint32( struct roundingData *roundData, float64 a ) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1728 | { |
| 1729 | flag aSign; |
| 1730 | int16 aExp, shiftCount; |
| 1731 | bits64 aSig; |
| 1732 | |
| 1733 | aSig = extractFloat64Frac( a ); |
| 1734 | aExp = extractFloat64Exp( a ); |
| 1735 | aSign = 0; //extractFloat64Sign( a ); |
| 1736 | //if ( ( aExp == 0x7FF ) && aSig ) aSign = 0; |
| 1737 | if ( aExp ) aSig |= LIT64( 0x0010000000000000 ); |
| 1738 | shiftCount = 0x42C - aExp; |
| 1739 | if ( 0 < shiftCount ) shift64RightJamming( aSig, shiftCount, &aSig ); |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 1740 | return roundAndPackInt32( roundData, aSign, aSig ); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1741 | } |
| 1742 | |
| 1743 | /* |
| 1744 | ------------------------------------------------------------------------------- |
| 1745 | Returns the result of converting the double-precision floating-point value |
| 1746 | `a' to the 32-bit two's complement integer format. The conversion is |
| 1747 | performed according to the IEC/IEEE Standard for Binary Floating-point |
| 1748 | Arithmetic, except that the conversion is always rounded toward zero. If |
| 1749 | `a' is a NaN, the largest positive integer is returned. Otherwise, if the |
| 1750 | conversion overflows, the largest positive integer is returned. |
| 1751 | ------------------------------------------------------------------------------- |
| 1752 | */ |
| 1753 | int32 float64_to_uint32_round_to_zero( float64 a ) |
| 1754 | { |
| 1755 | flag aSign; |
| 1756 | int16 aExp, shiftCount; |
| 1757 | bits64 aSig, savedASig; |
| 1758 | int32 z; |
| 1759 | |
| 1760 | aSig = extractFloat64Frac( a ); |
| 1761 | aExp = extractFloat64Exp( a ); |
| 1762 | aSign = extractFloat64Sign( a ); |
| 1763 | shiftCount = 0x433 - aExp; |
| 1764 | if ( shiftCount < 21 ) { |
| 1765 | if ( ( aExp == 0x7FF ) && aSig ) aSign = 0; |
| 1766 | goto invalid; |
| 1767 | } |
| 1768 | else if ( 52 < shiftCount ) { |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 1769 | if ( aExp || aSig ) float_raise( float_flag_inexact ); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1770 | return 0; |
| 1771 | } |
| 1772 | aSig |= LIT64( 0x0010000000000000 ); |
| 1773 | savedASig = aSig; |
| 1774 | aSig >>= shiftCount; |
| 1775 | z = aSig; |
| 1776 | if ( aSign ) z = - z; |
| 1777 | if ( ( z < 0 ) ^ aSign ) { |
| 1778 | invalid: |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 1779 | float_raise( float_flag_invalid ); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1780 | return aSign ? 0x80000000 : 0x7FFFFFFF; |
| 1781 | } |
| 1782 | if ( ( aSig<<shiftCount ) != savedASig ) { |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 1783 | float_raise( float_flag_inexact ); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1784 | } |
| 1785 | return z; |
| 1786 | } |
| 1787 | |
| 1788 | /* |
| 1789 | ------------------------------------------------------------------------------- |
| 1790 | Returns the result of converting the double-precision floating-point value |
| 1791 | `a' to the single-precision floating-point format. The conversion is |
| 1792 | performed according to the IEC/IEEE Standard for Binary Floating-point |
| 1793 | Arithmetic. |
| 1794 | ------------------------------------------------------------------------------- |
| 1795 | */ |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 1796 | float32 float64_to_float32( struct roundingData *roundData, float64 a ) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1797 | { |
| 1798 | flag aSign; |
| 1799 | int16 aExp; |
| 1800 | bits64 aSig; |
| 1801 | bits32 zSig; |
| 1802 | |
| 1803 | aSig = extractFloat64Frac( a ); |
| 1804 | aExp = extractFloat64Exp( a ); |
| 1805 | aSign = extractFloat64Sign( a ); |
| 1806 | if ( aExp == 0x7FF ) { |
| 1807 | if ( aSig ) return commonNaNToFloat32( float64ToCommonNaN( a ) ); |
| 1808 | return packFloat32( aSign, 0xFF, 0 ); |
| 1809 | } |
| 1810 | shift64RightJamming( aSig, 22, &aSig ); |
| 1811 | zSig = aSig; |
| 1812 | if ( aExp || zSig ) { |
| 1813 | zSig |= 0x40000000; |
| 1814 | aExp -= 0x381; |
| 1815 | } |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 1816 | return roundAndPackFloat32( roundData, aSign, aExp, zSig ); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1817 | |
| 1818 | } |
| 1819 | |
| 1820 | #ifdef FLOATX80 |
| 1821 | |
| 1822 | /* |
| 1823 | ------------------------------------------------------------------------------- |
| 1824 | Returns the result of converting the double-precision floating-point value |
| 1825 | `a' to the extended double-precision floating-point format. The conversion |
| 1826 | is performed according to the IEC/IEEE Standard for Binary Floating-point |
| 1827 | Arithmetic. |
| 1828 | ------------------------------------------------------------------------------- |
| 1829 | */ |
| 1830 | floatx80 float64_to_floatx80( float64 a ) |
| 1831 | { |
| 1832 | flag aSign; |
| 1833 | int16 aExp; |
| 1834 | bits64 aSig; |
| 1835 | |
| 1836 | aSig = extractFloat64Frac( a ); |
| 1837 | aExp = extractFloat64Exp( a ); |
| 1838 | aSign = extractFloat64Sign( a ); |
| 1839 | if ( aExp == 0x7FF ) { |
| 1840 | if ( aSig ) return commonNaNToFloatx80( float64ToCommonNaN( a ) ); |
| 1841 | return packFloatx80( aSign, 0x7FFF, LIT64( 0x8000000000000000 ) ); |
| 1842 | } |
| 1843 | if ( aExp == 0 ) { |
| 1844 | if ( aSig == 0 ) return packFloatx80( aSign, 0, 0 ); |
| 1845 | normalizeFloat64Subnormal( aSig, &aExp, &aSig ); |
| 1846 | } |
| 1847 | return |
| 1848 | packFloatx80( |
| 1849 | aSign, aExp + 0x3C00, ( aSig | LIT64( 0x0010000000000000 ) )<<11 ); |
| 1850 | |
| 1851 | } |
| 1852 | |
| 1853 | #endif |
| 1854 | |
| 1855 | /* |
| 1856 | ------------------------------------------------------------------------------- |
| 1857 | Rounds the double-precision floating-point value `a' to an integer, and |
| 1858 | returns the result as a double-precision floating-point value. The |
| 1859 | operation is performed according to the IEC/IEEE Standard for Binary |
| 1860 | Floating-point Arithmetic. |
| 1861 | ------------------------------------------------------------------------------- |
| 1862 | */ |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 1863 | float64 float64_round_to_int( struct roundingData *roundData, float64 a ) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1864 | { |
| 1865 | flag aSign; |
| 1866 | int16 aExp; |
| 1867 | bits64 lastBitMask, roundBitsMask; |
| 1868 | int8 roundingMode; |
| 1869 | float64 z; |
| 1870 | |
| 1871 | aExp = extractFloat64Exp( a ); |
| 1872 | if ( 0x433 <= aExp ) { |
| 1873 | if ( ( aExp == 0x7FF ) && extractFloat64Frac( a ) ) { |
| 1874 | return propagateFloat64NaN( a, a ); |
| 1875 | } |
| 1876 | return a; |
| 1877 | } |
| 1878 | if ( aExp <= 0x3FE ) { |
| 1879 | if ( (bits64) ( a<<1 ) == 0 ) return a; |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 1880 | roundData->exception |= float_flag_inexact; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1881 | aSign = extractFloat64Sign( a ); |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 1882 | switch ( roundData->mode ) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1883 | case float_round_nearest_even: |
| 1884 | if ( ( aExp == 0x3FE ) && extractFloat64Frac( a ) ) { |
| 1885 | return packFloat64( aSign, 0x3FF, 0 ); |
| 1886 | } |
| 1887 | break; |
| 1888 | case float_round_down: |
| 1889 | return aSign ? LIT64( 0xBFF0000000000000 ) : 0; |
| 1890 | case float_round_up: |
| 1891 | return |
| 1892 | aSign ? LIT64( 0x8000000000000000 ) : LIT64( 0x3FF0000000000000 ); |
| 1893 | } |
| 1894 | return packFloat64( aSign, 0, 0 ); |
| 1895 | } |
| 1896 | lastBitMask = 1; |
| 1897 | lastBitMask <<= 0x433 - aExp; |
| 1898 | roundBitsMask = lastBitMask - 1; |
| 1899 | z = a; |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 1900 | roundingMode = roundData->mode; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1901 | if ( roundingMode == float_round_nearest_even ) { |
| 1902 | z += lastBitMask>>1; |
| 1903 | if ( ( z & roundBitsMask ) == 0 ) z &= ~ lastBitMask; |
| 1904 | } |
| 1905 | else if ( roundingMode != float_round_to_zero ) { |
| 1906 | if ( extractFloat64Sign( z ) ^ ( roundingMode == float_round_up ) ) { |
| 1907 | z += roundBitsMask; |
| 1908 | } |
| 1909 | } |
| 1910 | z &= ~ roundBitsMask; |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 1911 | if ( z != a ) roundData->exception |= float_flag_inexact; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1912 | return z; |
| 1913 | |
| 1914 | } |
| 1915 | |
| 1916 | /* |
| 1917 | ------------------------------------------------------------------------------- |
| 1918 | Returns the result of adding the absolute values of the double-precision |
| 1919 | floating-point values `a' and `b'. If `zSign' is true, the sum is negated |
| 1920 | before being returned. `zSign' is ignored if the result is a NaN. The |
| 1921 | addition is performed according to the IEC/IEEE Standard for Binary |
| 1922 | Floating-point Arithmetic. |
| 1923 | ------------------------------------------------------------------------------- |
| 1924 | */ |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 1925 | static float64 addFloat64Sigs( struct roundingData *roundData, float64 a, float64 b, flag zSign ) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1926 | { |
| 1927 | int16 aExp, bExp, zExp; |
| 1928 | bits64 aSig, bSig, zSig; |
| 1929 | int16 expDiff; |
| 1930 | |
| 1931 | aSig = extractFloat64Frac( a ); |
| 1932 | aExp = extractFloat64Exp( a ); |
| 1933 | bSig = extractFloat64Frac( b ); |
| 1934 | bExp = extractFloat64Exp( b ); |
| 1935 | expDiff = aExp - bExp; |
| 1936 | aSig <<= 9; |
| 1937 | bSig <<= 9; |
| 1938 | if ( 0 < expDiff ) { |
| 1939 | if ( aExp == 0x7FF ) { |
| 1940 | if ( aSig ) return propagateFloat64NaN( a, b ); |
| 1941 | return a; |
| 1942 | } |
| 1943 | if ( bExp == 0 ) { |
| 1944 | --expDiff; |
| 1945 | } |
| 1946 | else { |
| 1947 | bSig |= LIT64( 0x2000000000000000 ); |
| 1948 | } |
| 1949 | shift64RightJamming( bSig, expDiff, &bSig ); |
| 1950 | zExp = aExp; |
| 1951 | } |
| 1952 | else if ( expDiff < 0 ) { |
| 1953 | if ( bExp == 0x7FF ) { |
| 1954 | if ( bSig ) return propagateFloat64NaN( a, b ); |
| 1955 | return packFloat64( zSign, 0x7FF, 0 ); |
| 1956 | } |
| 1957 | if ( aExp == 0 ) { |
| 1958 | ++expDiff; |
| 1959 | } |
| 1960 | else { |
| 1961 | aSig |= LIT64( 0x2000000000000000 ); |
| 1962 | } |
| 1963 | shift64RightJamming( aSig, - expDiff, &aSig ); |
| 1964 | zExp = bExp; |
| 1965 | } |
| 1966 | else { |
| 1967 | if ( aExp == 0x7FF ) { |
| 1968 | if ( aSig | bSig ) return propagateFloat64NaN( a, b ); |
| 1969 | return a; |
| 1970 | } |
| 1971 | if ( aExp == 0 ) return packFloat64( zSign, 0, ( aSig + bSig )>>9 ); |
| 1972 | zSig = LIT64( 0x4000000000000000 ) + aSig + bSig; |
| 1973 | zExp = aExp; |
| 1974 | goto roundAndPack; |
| 1975 | } |
| 1976 | aSig |= LIT64( 0x2000000000000000 ); |
| 1977 | zSig = ( aSig + bSig )<<1; |
| 1978 | --zExp; |
| 1979 | if ( (sbits64) zSig < 0 ) { |
| 1980 | zSig = aSig + bSig; |
| 1981 | ++zExp; |
| 1982 | } |
| 1983 | roundAndPack: |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 1984 | return roundAndPackFloat64( roundData, zSign, zExp, zSig ); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1985 | |
| 1986 | } |
| 1987 | |
| 1988 | /* |
| 1989 | ------------------------------------------------------------------------------- |
| 1990 | Returns the result of subtracting the absolute values of the double- |
| 1991 | precision floating-point values `a' and `b'. If `zSign' is true, the |
| 1992 | difference is negated before being returned. `zSign' is ignored if the |
| 1993 | result is a NaN. The subtraction is performed according to the IEC/IEEE |
| 1994 | Standard for Binary Floating-point Arithmetic. |
| 1995 | ------------------------------------------------------------------------------- |
| 1996 | */ |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 1997 | static float64 subFloat64Sigs( struct roundingData *roundData, float64 a, float64 b, flag zSign ) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1998 | { |
| 1999 | int16 aExp, bExp, zExp; |
| 2000 | bits64 aSig, bSig, zSig; |
| 2001 | int16 expDiff; |
| 2002 | |
| 2003 | aSig = extractFloat64Frac( a ); |
| 2004 | aExp = extractFloat64Exp( a ); |
| 2005 | bSig = extractFloat64Frac( b ); |
| 2006 | bExp = extractFloat64Exp( b ); |
| 2007 | expDiff = aExp - bExp; |
| 2008 | aSig <<= 10; |
| 2009 | bSig <<= 10; |
| 2010 | if ( 0 < expDiff ) goto aExpBigger; |
| 2011 | if ( expDiff < 0 ) goto bExpBigger; |
| 2012 | if ( aExp == 0x7FF ) { |
| 2013 | if ( aSig | bSig ) return propagateFloat64NaN( a, b ); |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 2014 | roundData->exception |= float_flag_invalid; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2015 | return float64_default_nan; |
| 2016 | } |
| 2017 | if ( aExp == 0 ) { |
| 2018 | aExp = 1; |
| 2019 | bExp = 1; |
| 2020 | } |
| 2021 | if ( bSig < aSig ) goto aBigger; |
| 2022 | if ( aSig < bSig ) goto bBigger; |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 2023 | return packFloat64( roundData->mode == float_round_down, 0, 0 ); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2024 | bExpBigger: |
| 2025 | if ( bExp == 0x7FF ) { |
| 2026 | if ( bSig ) return propagateFloat64NaN( a, b ); |
| 2027 | return packFloat64( zSign ^ 1, 0x7FF, 0 ); |
| 2028 | } |
| 2029 | if ( aExp == 0 ) { |
| 2030 | ++expDiff; |
| 2031 | } |
| 2032 | else { |
| 2033 | aSig |= LIT64( 0x4000000000000000 ); |
| 2034 | } |
| 2035 | shift64RightJamming( aSig, - expDiff, &aSig ); |
| 2036 | bSig |= LIT64( 0x4000000000000000 ); |
| 2037 | bBigger: |
| 2038 | zSig = bSig - aSig; |
| 2039 | zExp = bExp; |
| 2040 | zSign ^= 1; |
| 2041 | goto normalizeRoundAndPack; |
| 2042 | aExpBigger: |
| 2043 | if ( aExp == 0x7FF ) { |
| 2044 | if ( aSig ) return propagateFloat64NaN( a, b ); |
| 2045 | return a; |
| 2046 | } |
| 2047 | if ( bExp == 0 ) { |
| 2048 | --expDiff; |
| 2049 | } |
| 2050 | else { |
| 2051 | bSig |= LIT64( 0x4000000000000000 ); |
| 2052 | } |
| 2053 | shift64RightJamming( bSig, expDiff, &bSig ); |
| 2054 | aSig |= LIT64( 0x4000000000000000 ); |
| 2055 | aBigger: |
| 2056 | zSig = aSig - bSig; |
| 2057 | zExp = aExp; |
| 2058 | normalizeRoundAndPack: |
| 2059 | --zExp; |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 2060 | return normalizeRoundAndPackFloat64( roundData, zSign, zExp, zSig ); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2061 | |
| 2062 | } |
| 2063 | |
| 2064 | /* |
| 2065 | ------------------------------------------------------------------------------- |
| 2066 | Returns the result of adding the double-precision floating-point values `a' |
| 2067 | and `b'. The operation is performed according to the IEC/IEEE Standard for |
| 2068 | Binary Floating-point Arithmetic. |
| 2069 | ------------------------------------------------------------------------------- |
| 2070 | */ |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 2071 | float64 float64_add( struct roundingData *roundData, float64 a, float64 b ) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2072 | { |
| 2073 | flag aSign, bSign; |
| 2074 | |
| 2075 | aSign = extractFloat64Sign( a ); |
| 2076 | bSign = extractFloat64Sign( b ); |
| 2077 | if ( aSign == bSign ) { |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 2078 | return addFloat64Sigs( roundData, a, b, aSign ); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2079 | } |
| 2080 | else { |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 2081 | return subFloat64Sigs( roundData, a, b, aSign ); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2082 | } |
| 2083 | |
| 2084 | } |
| 2085 | |
| 2086 | /* |
| 2087 | ------------------------------------------------------------------------------- |
| 2088 | Returns the result of subtracting the double-precision floating-point values |
| 2089 | `a' and `b'. The operation is performed according to the IEC/IEEE Standard |
| 2090 | for Binary Floating-point Arithmetic. |
| 2091 | ------------------------------------------------------------------------------- |
| 2092 | */ |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 2093 | float64 float64_sub( struct roundingData *roundData, float64 a, float64 b ) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2094 | { |
| 2095 | flag aSign, bSign; |
| 2096 | |
| 2097 | aSign = extractFloat64Sign( a ); |
| 2098 | bSign = extractFloat64Sign( b ); |
| 2099 | if ( aSign == bSign ) { |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 2100 | return subFloat64Sigs( roundData, a, b, aSign ); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2101 | } |
| 2102 | else { |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 2103 | return addFloat64Sigs( roundData, a, b, aSign ); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2104 | } |
| 2105 | |
| 2106 | } |
| 2107 | |
| 2108 | /* |
| 2109 | ------------------------------------------------------------------------------- |
| 2110 | Returns the result of multiplying the double-precision floating-point values |
| 2111 | `a' and `b'. The operation is performed according to the IEC/IEEE Standard |
| 2112 | for Binary Floating-point Arithmetic. |
| 2113 | ------------------------------------------------------------------------------- |
| 2114 | */ |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 2115 | float64 float64_mul( struct roundingData *roundData, float64 a, float64 b ) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2116 | { |
| 2117 | flag aSign, bSign, zSign; |
| 2118 | int16 aExp, bExp, zExp; |
| 2119 | bits64 aSig, bSig, zSig0, zSig1; |
| 2120 | |
| 2121 | aSig = extractFloat64Frac( a ); |
| 2122 | aExp = extractFloat64Exp( a ); |
| 2123 | aSign = extractFloat64Sign( a ); |
| 2124 | bSig = extractFloat64Frac( b ); |
| 2125 | bExp = extractFloat64Exp( b ); |
| 2126 | bSign = extractFloat64Sign( b ); |
| 2127 | zSign = aSign ^ bSign; |
| 2128 | if ( aExp == 0x7FF ) { |
| 2129 | if ( aSig || ( ( bExp == 0x7FF ) && bSig ) ) { |
| 2130 | return propagateFloat64NaN( a, b ); |
| 2131 | } |
| 2132 | if ( ( bExp | bSig ) == 0 ) { |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 2133 | roundData->exception |= float_flag_invalid; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2134 | return float64_default_nan; |
| 2135 | } |
| 2136 | return packFloat64( zSign, 0x7FF, 0 ); |
| 2137 | } |
| 2138 | if ( bExp == 0x7FF ) { |
| 2139 | if ( bSig ) return propagateFloat64NaN( a, b ); |
| 2140 | if ( ( aExp | aSig ) == 0 ) { |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 2141 | roundData->exception |= float_flag_invalid; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2142 | return float64_default_nan; |
| 2143 | } |
| 2144 | return packFloat64( zSign, 0x7FF, 0 ); |
| 2145 | } |
| 2146 | if ( aExp == 0 ) { |
| 2147 | if ( aSig == 0 ) return packFloat64( zSign, 0, 0 ); |
| 2148 | normalizeFloat64Subnormal( aSig, &aExp, &aSig ); |
| 2149 | } |
| 2150 | if ( bExp == 0 ) { |
| 2151 | if ( bSig == 0 ) return packFloat64( zSign, 0, 0 ); |
| 2152 | normalizeFloat64Subnormal( bSig, &bExp, &bSig ); |
| 2153 | } |
| 2154 | zExp = aExp + bExp - 0x3FF; |
| 2155 | aSig = ( aSig | LIT64( 0x0010000000000000 ) )<<10; |
| 2156 | bSig = ( bSig | LIT64( 0x0010000000000000 ) )<<11; |
| 2157 | mul64To128( aSig, bSig, &zSig0, &zSig1 ); |
| 2158 | zSig0 |= ( zSig1 != 0 ); |
| 2159 | if ( 0 <= (sbits64) ( zSig0<<1 ) ) { |
| 2160 | zSig0 <<= 1; |
| 2161 | --zExp; |
| 2162 | } |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 2163 | return roundAndPackFloat64( roundData, zSign, zExp, zSig0 ); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2164 | |
| 2165 | } |
| 2166 | |
| 2167 | /* |
| 2168 | ------------------------------------------------------------------------------- |
| 2169 | Returns the result of dividing the double-precision floating-point value `a' |
| 2170 | by the corresponding value `b'. The operation is performed according to |
| 2171 | the IEC/IEEE Standard for Binary Floating-point Arithmetic. |
| 2172 | ------------------------------------------------------------------------------- |
| 2173 | */ |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 2174 | float64 float64_div( struct roundingData *roundData, float64 a, float64 b ) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2175 | { |
| 2176 | flag aSign, bSign, zSign; |
| 2177 | int16 aExp, bExp, zExp; |
| 2178 | bits64 aSig, bSig, zSig; |
| 2179 | bits64 rem0, rem1; |
| 2180 | bits64 term0, term1; |
| 2181 | |
| 2182 | aSig = extractFloat64Frac( a ); |
| 2183 | aExp = extractFloat64Exp( a ); |
| 2184 | aSign = extractFloat64Sign( a ); |
| 2185 | bSig = extractFloat64Frac( b ); |
| 2186 | bExp = extractFloat64Exp( b ); |
| 2187 | bSign = extractFloat64Sign( b ); |
| 2188 | zSign = aSign ^ bSign; |
| 2189 | if ( aExp == 0x7FF ) { |
| 2190 | if ( aSig ) return propagateFloat64NaN( a, b ); |
| 2191 | if ( bExp == 0x7FF ) { |
| 2192 | if ( bSig ) return propagateFloat64NaN( a, b ); |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 2193 | roundData->exception |= float_flag_invalid; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2194 | return float64_default_nan; |
| 2195 | } |
| 2196 | return packFloat64( zSign, 0x7FF, 0 ); |
| 2197 | } |
| 2198 | if ( bExp == 0x7FF ) { |
| 2199 | if ( bSig ) return propagateFloat64NaN( a, b ); |
| 2200 | return packFloat64( zSign, 0, 0 ); |
| 2201 | } |
| 2202 | if ( bExp == 0 ) { |
| 2203 | if ( bSig == 0 ) { |
| 2204 | if ( ( aExp | aSig ) == 0 ) { |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 2205 | roundData->exception |= float_flag_invalid; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2206 | return float64_default_nan; |
| 2207 | } |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 2208 | roundData->exception |= float_flag_divbyzero; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2209 | return packFloat64( zSign, 0x7FF, 0 ); |
| 2210 | } |
| 2211 | normalizeFloat64Subnormal( bSig, &bExp, &bSig ); |
| 2212 | } |
| 2213 | if ( aExp == 0 ) { |
| 2214 | if ( aSig == 0 ) return packFloat64( zSign, 0, 0 ); |
| 2215 | normalizeFloat64Subnormal( aSig, &aExp, &aSig ); |
| 2216 | } |
| 2217 | zExp = aExp - bExp + 0x3FD; |
| 2218 | aSig = ( aSig | LIT64( 0x0010000000000000 ) )<<10; |
| 2219 | bSig = ( bSig | LIT64( 0x0010000000000000 ) )<<11; |
| 2220 | if ( bSig <= ( aSig + aSig ) ) { |
| 2221 | aSig >>= 1; |
| 2222 | ++zExp; |
| 2223 | } |
| 2224 | zSig = estimateDiv128To64( aSig, 0, bSig ); |
| 2225 | if ( ( zSig & 0x1FF ) <= 2 ) { |
| 2226 | mul64To128( bSig, zSig, &term0, &term1 ); |
| 2227 | sub128( aSig, 0, term0, term1, &rem0, &rem1 ); |
| 2228 | while ( (sbits64) rem0 < 0 ) { |
| 2229 | --zSig; |
| 2230 | add128( rem0, rem1, 0, bSig, &rem0, &rem1 ); |
| 2231 | } |
| 2232 | zSig |= ( rem1 != 0 ); |
| 2233 | } |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 2234 | return roundAndPackFloat64( roundData, zSign, zExp, zSig ); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2235 | |
| 2236 | } |
| 2237 | |
| 2238 | /* |
| 2239 | ------------------------------------------------------------------------------- |
| 2240 | Returns the remainder of the double-precision floating-point value `a' |
| 2241 | with respect to the corresponding value `b'. The operation is performed |
| 2242 | according to the IEC/IEEE Standard for Binary Floating-point Arithmetic. |
| 2243 | ------------------------------------------------------------------------------- |
| 2244 | */ |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 2245 | float64 float64_rem( struct roundingData *roundData, float64 a, float64 b ) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2246 | { |
| 2247 | flag aSign, bSign, zSign; |
| 2248 | int16 aExp, bExp, expDiff; |
| 2249 | bits64 aSig, bSig; |
| 2250 | bits64 q, alternateASig; |
| 2251 | sbits64 sigMean; |
| 2252 | |
| 2253 | aSig = extractFloat64Frac( a ); |
| 2254 | aExp = extractFloat64Exp( a ); |
| 2255 | aSign = extractFloat64Sign( a ); |
| 2256 | bSig = extractFloat64Frac( b ); |
| 2257 | bExp = extractFloat64Exp( b ); |
| 2258 | bSign = extractFloat64Sign( b ); |
| 2259 | if ( aExp == 0x7FF ) { |
| 2260 | if ( aSig || ( ( bExp == 0x7FF ) && bSig ) ) { |
| 2261 | return propagateFloat64NaN( a, b ); |
| 2262 | } |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 2263 | roundData->exception |= float_flag_invalid; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2264 | return float64_default_nan; |
| 2265 | } |
| 2266 | if ( bExp == 0x7FF ) { |
| 2267 | if ( bSig ) return propagateFloat64NaN( a, b ); |
| 2268 | return a; |
| 2269 | } |
| 2270 | if ( bExp == 0 ) { |
| 2271 | if ( bSig == 0 ) { |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 2272 | roundData->exception |= float_flag_invalid; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2273 | return float64_default_nan; |
| 2274 | } |
| 2275 | normalizeFloat64Subnormal( bSig, &bExp, &bSig ); |
| 2276 | } |
| 2277 | if ( aExp == 0 ) { |
| 2278 | if ( aSig == 0 ) return a; |
| 2279 | normalizeFloat64Subnormal( aSig, &aExp, &aSig ); |
| 2280 | } |
| 2281 | expDiff = aExp - bExp; |
| 2282 | aSig = ( aSig | LIT64( 0x0010000000000000 ) )<<11; |
| 2283 | bSig = ( bSig | LIT64( 0x0010000000000000 ) )<<11; |
| 2284 | if ( expDiff < 0 ) { |
| 2285 | if ( expDiff < -1 ) return a; |
| 2286 | aSig >>= 1; |
| 2287 | } |
| 2288 | q = ( bSig <= aSig ); |
| 2289 | if ( q ) aSig -= bSig; |
| 2290 | expDiff -= 64; |
| 2291 | while ( 0 < expDiff ) { |
| 2292 | q = estimateDiv128To64( aSig, 0, bSig ); |
| 2293 | q = ( 2 < q ) ? q - 2 : 0; |
| 2294 | aSig = - ( ( bSig>>2 ) * q ); |
| 2295 | expDiff -= 62; |
| 2296 | } |
| 2297 | expDiff += 64; |
| 2298 | if ( 0 < expDiff ) { |
| 2299 | q = estimateDiv128To64( aSig, 0, bSig ); |
| 2300 | q = ( 2 < q ) ? q - 2 : 0; |
| 2301 | q >>= 64 - expDiff; |
| 2302 | bSig >>= 2; |
| 2303 | aSig = ( ( aSig>>1 )<<( expDiff - 1 ) ) - bSig * q; |
| 2304 | } |
| 2305 | else { |
| 2306 | aSig >>= 2; |
| 2307 | bSig >>= 2; |
| 2308 | } |
| 2309 | do { |
| 2310 | alternateASig = aSig; |
| 2311 | ++q; |
| 2312 | aSig -= bSig; |
| 2313 | } while ( 0 <= (sbits64) aSig ); |
| 2314 | sigMean = aSig + alternateASig; |
| 2315 | if ( ( sigMean < 0 ) || ( ( sigMean == 0 ) && ( q & 1 ) ) ) { |
| 2316 | aSig = alternateASig; |
| 2317 | } |
| 2318 | zSign = ( (sbits64) aSig < 0 ); |
| 2319 | if ( zSign ) aSig = - aSig; |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 2320 | return normalizeRoundAndPackFloat64( roundData, aSign ^ zSign, bExp, aSig ); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2321 | |
| 2322 | } |
| 2323 | |
| 2324 | /* |
| 2325 | ------------------------------------------------------------------------------- |
| 2326 | Returns the square root of the double-precision floating-point value `a'. |
| 2327 | The operation is performed according to the IEC/IEEE Standard for Binary |
| 2328 | Floating-point Arithmetic. |
| 2329 | ------------------------------------------------------------------------------- |
| 2330 | */ |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 2331 | float64 float64_sqrt( struct roundingData *roundData, float64 a ) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2332 | { |
| 2333 | flag aSign; |
| 2334 | int16 aExp, zExp; |
| 2335 | bits64 aSig, zSig; |
| 2336 | bits64 rem0, rem1, term0, term1; //, shiftedRem; |
| 2337 | //float64 z; |
| 2338 | |
| 2339 | aSig = extractFloat64Frac( a ); |
| 2340 | aExp = extractFloat64Exp( a ); |
| 2341 | aSign = extractFloat64Sign( a ); |
| 2342 | if ( aExp == 0x7FF ) { |
| 2343 | if ( aSig ) return propagateFloat64NaN( a, a ); |
| 2344 | if ( ! aSign ) return a; |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 2345 | roundData->exception |= float_flag_invalid; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2346 | return float64_default_nan; |
| 2347 | } |
| 2348 | if ( aSign ) { |
| 2349 | if ( ( aExp | aSig ) == 0 ) return a; |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 2350 | roundData->exception |= float_flag_invalid; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2351 | return float64_default_nan; |
| 2352 | } |
| 2353 | if ( aExp == 0 ) { |
| 2354 | if ( aSig == 0 ) return 0; |
| 2355 | normalizeFloat64Subnormal( aSig, &aExp, &aSig ); |
| 2356 | } |
| 2357 | zExp = ( ( aExp - 0x3FF )>>1 ) + 0x3FE; |
| 2358 | aSig |= LIT64( 0x0010000000000000 ); |
| 2359 | zSig = estimateSqrt32( aExp, aSig>>21 ); |
| 2360 | zSig <<= 31; |
| 2361 | aSig <<= 9 - ( aExp & 1 ); |
| 2362 | zSig = estimateDiv128To64( aSig, 0, zSig ) + zSig + 2; |
| 2363 | if ( ( zSig & 0x3FF ) <= 5 ) { |
| 2364 | if ( zSig < 2 ) { |
| 2365 | zSig = LIT64( 0xFFFFFFFFFFFFFFFF ); |
| 2366 | } |
| 2367 | else { |
| 2368 | aSig <<= 2; |
| 2369 | mul64To128( zSig, zSig, &term0, &term1 ); |
| 2370 | sub128( aSig, 0, term0, term1, &rem0, &rem1 ); |
| 2371 | while ( (sbits64) rem0 < 0 ) { |
| 2372 | --zSig; |
| 2373 | shortShift128Left( 0, zSig, 1, &term0, &term1 ); |
| 2374 | term1 |= 1; |
| 2375 | add128( rem0, rem1, term0, term1, &rem0, &rem1 ); |
| 2376 | } |
| 2377 | zSig |= ( ( rem0 | rem1 ) != 0 ); |
| 2378 | } |
| 2379 | } |
| 2380 | shift64RightJamming( zSig, 1, &zSig ); |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 2381 | return roundAndPackFloat64( roundData, 0, zExp, zSig ); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2382 | |
| 2383 | } |
| 2384 | |
| 2385 | /* |
| 2386 | ------------------------------------------------------------------------------- |
| 2387 | Returns 1 if the double-precision floating-point value `a' is equal to the |
| 2388 | corresponding value `b', and 0 otherwise. The comparison is performed |
| 2389 | according to the IEC/IEEE Standard for Binary Floating-point Arithmetic. |
| 2390 | ------------------------------------------------------------------------------- |
| 2391 | */ |
| 2392 | flag float64_eq( float64 a, float64 b ) |
| 2393 | { |
| 2394 | |
| 2395 | if ( ( ( extractFloat64Exp( a ) == 0x7FF ) && extractFloat64Frac( a ) ) |
| 2396 | || ( ( extractFloat64Exp( b ) == 0x7FF ) && extractFloat64Frac( b ) ) |
| 2397 | ) { |
| 2398 | if ( float64_is_signaling_nan( a ) || float64_is_signaling_nan( b ) ) { |
| 2399 | float_raise( float_flag_invalid ); |
| 2400 | } |
| 2401 | return 0; |
| 2402 | } |
| 2403 | return ( a == b ) || ( (bits64) ( ( a | b )<<1 ) == 0 ); |
| 2404 | |
| 2405 | } |
| 2406 | |
| 2407 | /* |
| 2408 | ------------------------------------------------------------------------------- |
| 2409 | Returns 1 if the double-precision floating-point value `a' is less than or |
| 2410 | equal to the corresponding value `b', and 0 otherwise. The comparison is |
| 2411 | performed according to the IEC/IEEE Standard for Binary Floating-point |
| 2412 | Arithmetic. |
| 2413 | ------------------------------------------------------------------------------- |
| 2414 | */ |
| 2415 | flag float64_le( float64 a, float64 b ) |
| 2416 | { |
| 2417 | flag aSign, bSign; |
| 2418 | |
| 2419 | if ( ( ( extractFloat64Exp( a ) == 0x7FF ) && extractFloat64Frac( a ) ) |
| 2420 | || ( ( extractFloat64Exp( b ) == 0x7FF ) && extractFloat64Frac( b ) ) |
| 2421 | ) { |
| 2422 | float_raise( float_flag_invalid ); |
| 2423 | return 0; |
| 2424 | } |
| 2425 | aSign = extractFloat64Sign( a ); |
| 2426 | bSign = extractFloat64Sign( b ); |
| 2427 | if ( aSign != bSign ) return aSign || ( (bits64) ( ( a | b )<<1 ) == 0 ); |
| 2428 | return ( a == b ) || ( aSign ^ ( a < b ) ); |
| 2429 | |
| 2430 | } |
| 2431 | |
| 2432 | /* |
| 2433 | ------------------------------------------------------------------------------- |
| 2434 | Returns 1 if the double-precision floating-point value `a' is less than |
| 2435 | the corresponding value `b', and 0 otherwise. The comparison is performed |
| 2436 | according to the IEC/IEEE Standard for Binary Floating-point Arithmetic. |
| 2437 | ------------------------------------------------------------------------------- |
| 2438 | */ |
| 2439 | flag float64_lt( float64 a, float64 b ) |
| 2440 | { |
| 2441 | flag aSign, bSign; |
| 2442 | |
| 2443 | if ( ( ( extractFloat64Exp( a ) == 0x7FF ) && extractFloat64Frac( a ) ) |
| 2444 | || ( ( extractFloat64Exp( b ) == 0x7FF ) && extractFloat64Frac( b ) ) |
| 2445 | ) { |
| 2446 | float_raise( float_flag_invalid ); |
| 2447 | return 0; |
| 2448 | } |
| 2449 | aSign = extractFloat64Sign( a ); |
| 2450 | bSign = extractFloat64Sign( b ); |
| 2451 | if ( aSign != bSign ) return aSign && ( (bits64) ( ( a | b )<<1 ) != 0 ); |
| 2452 | return ( a != b ) && ( aSign ^ ( a < b ) ); |
| 2453 | |
| 2454 | } |
| 2455 | |
| 2456 | /* |
| 2457 | ------------------------------------------------------------------------------- |
| 2458 | Returns 1 if the double-precision floating-point value `a' is equal to the |
| 2459 | corresponding value `b', and 0 otherwise. The invalid exception is raised |
| 2460 | if either operand is a NaN. Otherwise, the comparison is performed |
| 2461 | according to the IEC/IEEE Standard for Binary Floating-point Arithmetic. |
| 2462 | ------------------------------------------------------------------------------- |
| 2463 | */ |
| 2464 | flag float64_eq_signaling( float64 a, float64 b ) |
| 2465 | { |
| 2466 | |
| 2467 | if ( ( ( extractFloat64Exp( a ) == 0x7FF ) && extractFloat64Frac( a ) ) |
| 2468 | || ( ( extractFloat64Exp( b ) == 0x7FF ) && extractFloat64Frac( b ) ) |
| 2469 | ) { |
| 2470 | float_raise( float_flag_invalid ); |
| 2471 | return 0; |
| 2472 | } |
| 2473 | return ( a == b ) || ( (bits64) ( ( a | b )<<1 ) == 0 ); |
| 2474 | |
| 2475 | } |
| 2476 | |
| 2477 | /* |
| 2478 | ------------------------------------------------------------------------------- |
| 2479 | Returns 1 if the double-precision floating-point value `a' is less than or |
| 2480 | equal to the corresponding value `b', and 0 otherwise. Quiet NaNs do not |
| 2481 | cause an exception. Otherwise, the comparison is performed according to the |
| 2482 | IEC/IEEE Standard for Binary Floating-point Arithmetic. |
| 2483 | ------------------------------------------------------------------------------- |
| 2484 | */ |
| 2485 | flag float64_le_quiet( float64 a, float64 b ) |
| 2486 | { |
| 2487 | flag aSign, bSign; |
| 2488 | //int16 aExp, bExp; |
| 2489 | |
| 2490 | if ( ( ( extractFloat64Exp( a ) == 0x7FF ) && extractFloat64Frac( a ) ) |
| 2491 | || ( ( extractFloat64Exp( b ) == 0x7FF ) && extractFloat64Frac( b ) ) |
| 2492 | ) { |
Richard Purdie | 54738e8 | 2005-08-15 20:42:32 +0100 | [diff] [blame] | 2493 | /* Do nothing, even if NaN as we're quiet */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2494 | return 0; |
| 2495 | } |
| 2496 | aSign = extractFloat64Sign( a ); |
| 2497 | bSign = extractFloat64Sign( b ); |
| 2498 | if ( aSign != bSign ) return aSign || ( (bits64) ( ( a | b )<<1 ) == 0 ); |
| 2499 | return ( a == b ) || ( aSign ^ ( a < b ) ); |
| 2500 | |
| 2501 | } |
| 2502 | |
| 2503 | /* |
| 2504 | ------------------------------------------------------------------------------- |
| 2505 | Returns 1 if the double-precision floating-point value `a' is less than |
| 2506 | the corresponding value `b', and 0 otherwise. Quiet NaNs do not cause an |
| 2507 | exception. Otherwise, the comparison is performed according to the IEC/IEEE |
| 2508 | Standard for Binary Floating-point Arithmetic. |
| 2509 | ------------------------------------------------------------------------------- |
| 2510 | */ |
| 2511 | flag float64_lt_quiet( float64 a, float64 b ) |
| 2512 | { |
| 2513 | flag aSign, bSign; |
| 2514 | |
| 2515 | if ( ( ( extractFloat64Exp( a ) == 0x7FF ) && extractFloat64Frac( a ) ) |
| 2516 | || ( ( extractFloat64Exp( b ) == 0x7FF ) && extractFloat64Frac( b ) ) |
| 2517 | ) { |
Richard Purdie | 54738e8 | 2005-08-15 20:42:32 +0100 | [diff] [blame] | 2518 | /* Do nothing, even if NaN as we're quiet */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2519 | return 0; |
| 2520 | } |
| 2521 | aSign = extractFloat64Sign( a ); |
| 2522 | bSign = extractFloat64Sign( b ); |
| 2523 | if ( aSign != bSign ) return aSign && ( (bits64) ( ( a | b )<<1 ) != 0 ); |
| 2524 | return ( a != b ) && ( aSign ^ ( a < b ) ); |
| 2525 | |
| 2526 | } |
| 2527 | |
| 2528 | #ifdef FLOATX80 |
| 2529 | |
| 2530 | /* |
| 2531 | ------------------------------------------------------------------------------- |
| 2532 | Returns the result of converting the extended double-precision floating- |
| 2533 | point value `a' to the 32-bit two's complement integer format. The |
| 2534 | conversion is performed according to the IEC/IEEE Standard for Binary |
| 2535 | Floating-point Arithmetic---which means in particular that the conversion |
| 2536 | is rounded according to the current rounding mode. If `a' is a NaN, the |
| 2537 | largest positive integer is returned. Otherwise, if the conversion |
| 2538 | overflows, the largest integer with the same sign as `a' is returned. |
| 2539 | ------------------------------------------------------------------------------- |
| 2540 | */ |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 2541 | int32 floatx80_to_int32( struct roundingData *roundData, floatx80 a ) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2542 | { |
| 2543 | flag aSign; |
| 2544 | int32 aExp, shiftCount; |
| 2545 | bits64 aSig; |
| 2546 | |
| 2547 | aSig = extractFloatx80Frac( a ); |
| 2548 | aExp = extractFloatx80Exp( a ); |
| 2549 | aSign = extractFloatx80Sign( a ); |
| 2550 | if ( ( aExp == 0x7FFF ) && (bits64) ( aSig<<1 ) ) aSign = 0; |
| 2551 | shiftCount = 0x4037 - aExp; |
| 2552 | if ( shiftCount <= 0 ) shiftCount = 1; |
| 2553 | shift64RightJamming( aSig, shiftCount, &aSig ); |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 2554 | return roundAndPackInt32( roundData, aSign, aSig ); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2555 | |
| 2556 | } |
| 2557 | |
| 2558 | /* |
| 2559 | ------------------------------------------------------------------------------- |
| 2560 | Returns the result of converting the extended double-precision floating- |
| 2561 | point value `a' to the 32-bit two's complement integer format. The |
| 2562 | conversion is performed according to the IEC/IEEE Standard for Binary |
| 2563 | Floating-point Arithmetic, except that the conversion is always rounded |
| 2564 | toward zero. If `a' is a NaN, the largest positive integer is returned. |
| 2565 | Otherwise, if the conversion overflows, the largest integer with the same |
| 2566 | sign as `a' is returned. |
| 2567 | ------------------------------------------------------------------------------- |
| 2568 | */ |
| 2569 | int32 floatx80_to_int32_round_to_zero( floatx80 a ) |
| 2570 | { |
| 2571 | flag aSign; |
| 2572 | int32 aExp, shiftCount; |
| 2573 | bits64 aSig, savedASig; |
| 2574 | int32 z; |
| 2575 | |
| 2576 | aSig = extractFloatx80Frac( a ); |
| 2577 | aExp = extractFloatx80Exp( a ); |
| 2578 | aSign = extractFloatx80Sign( a ); |
| 2579 | shiftCount = 0x403E - aExp; |
| 2580 | if ( shiftCount < 32 ) { |
| 2581 | if ( ( aExp == 0x7FFF ) && (bits64) ( aSig<<1 ) ) aSign = 0; |
| 2582 | goto invalid; |
| 2583 | } |
| 2584 | else if ( 63 < shiftCount ) { |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 2585 | if ( aExp || aSig ) float_raise( float_flag_inexact ); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2586 | return 0; |
| 2587 | } |
| 2588 | savedASig = aSig; |
| 2589 | aSig >>= shiftCount; |
| 2590 | z = aSig; |
| 2591 | if ( aSign ) z = - z; |
| 2592 | if ( ( z < 0 ) ^ aSign ) { |
| 2593 | invalid: |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 2594 | float_raise( float_flag_invalid ); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2595 | return aSign ? 0x80000000 : 0x7FFFFFFF; |
| 2596 | } |
| 2597 | if ( ( aSig<<shiftCount ) != savedASig ) { |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 2598 | float_raise( float_flag_inexact ); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2599 | } |
| 2600 | return z; |
| 2601 | |
| 2602 | } |
| 2603 | |
| 2604 | /* |
| 2605 | ------------------------------------------------------------------------------- |
| 2606 | Returns the result of converting the extended double-precision floating- |
| 2607 | point value `a' to the single-precision floating-point format. The |
| 2608 | conversion is performed according to the IEC/IEEE Standard for Binary |
| 2609 | Floating-point Arithmetic. |
| 2610 | ------------------------------------------------------------------------------- |
| 2611 | */ |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 2612 | float32 floatx80_to_float32( struct roundingData *roundData, floatx80 a ) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2613 | { |
| 2614 | flag aSign; |
| 2615 | int32 aExp; |
| 2616 | bits64 aSig; |
| 2617 | |
| 2618 | aSig = extractFloatx80Frac( a ); |
| 2619 | aExp = extractFloatx80Exp( a ); |
| 2620 | aSign = extractFloatx80Sign( a ); |
| 2621 | if ( aExp == 0x7FFF ) { |
| 2622 | if ( (bits64) ( aSig<<1 ) ) { |
| 2623 | return commonNaNToFloat32( floatx80ToCommonNaN( a ) ); |
| 2624 | } |
| 2625 | return packFloat32( aSign, 0xFF, 0 ); |
| 2626 | } |
| 2627 | shift64RightJamming( aSig, 33, &aSig ); |
| 2628 | if ( aExp || aSig ) aExp -= 0x3F81; |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 2629 | return roundAndPackFloat32( roundData, aSign, aExp, aSig ); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2630 | |
| 2631 | } |
| 2632 | |
| 2633 | /* |
| 2634 | ------------------------------------------------------------------------------- |
| 2635 | Returns the result of converting the extended double-precision floating- |
| 2636 | point value `a' to the double-precision floating-point format. The |
| 2637 | conversion is performed according to the IEC/IEEE Standard for Binary |
| 2638 | Floating-point Arithmetic. |
| 2639 | ------------------------------------------------------------------------------- |
| 2640 | */ |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 2641 | float64 floatx80_to_float64( struct roundingData *roundData, floatx80 a ) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2642 | { |
| 2643 | flag aSign; |
| 2644 | int32 aExp; |
| 2645 | bits64 aSig, zSig; |
| 2646 | |
| 2647 | aSig = extractFloatx80Frac( a ); |
| 2648 | aExp = extractFloatx80Exp( a ); |
| 2649 | aSign = extractFloatx80Sign( a ); |
| 2650 | if ( aExp == 0x7FFF ) { |
| 2651 | if ( (bits64) ( aSig<<1 ) ) { |
| 2652 | return commonNaNToFloat64( floatx80ToCommonNaN( a ) ); |
| 2653 | } |
| 2654 | return packFloat64( aSign, 0x7FF, 0 ); |
| 2655 | } |
| 2656 | shift64RightJamming( aSig, 1, &zSig ); |
| 2657 | if ( aExp || aSig ) aExp -= 0x3C01; |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 2658 | return roundAndPackFloat64( roundData, aSign, aExp, zSig ); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2659 | |
| 2660 | } |
| 2661 | |
| 2662 | /* |
| 2663 | ------------------------------------------------------------------------------- |
| 2664 | Rounds the extended double-precision floating-point value `a' to an integer, |
| 2665 | and returns the result as an extended quadruple-precision floating-point |
| 2666 | value. The operation is performed according to the IEC/IEEE Standard for |
| 2667 | Binary Floating-point Arithmetic. |
| 2668 | ------------------------------------------------------------------------------- |
| 2669 | */ |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 2670 | floatx80 floatx80_round_to_int( struct roundingData *roundData, floatx80 a ) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2671 | { |
| 2672 | flag aSign; |
| 2673 | int32 aExp; |
| 2674 | bits64 lastBitMask, roundBitsMask; |
| 2675 | int8 roundingMode; |
| 2676 | floatx80 z; |
| 2677 | |
| 2678 | aExp = extractFloatx80Exp( a ); |
| 2679 | if ( 0x403E <= aExp ) { |
| 2680 | if ( ( aExp == 0x7FFF ) && (bits64) ( extractFloatx80Frac( a )<<1 ) ) { |
| 2681 | return propagateFloatx80NaN( a, a ); |
| 2682 | } |
| 2683 | return a; |
| 2684 | } |
| 2685 | if ( aExp <= 0x3FFE ) { |
| 2686 | if ( ( aExp == 0 ) |
| 2687 | && ( (bits64) ( extractFloatx80Frac( a )<<1 ) == 0 ) ) { |
| 2688 | return a; |
| 2689 | } |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 2690 | roundData->exception |= float_flag_inexact; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2691 | aSign = extractFloatx80Sign( a ); |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 2692 | switch ( roundData->mode ) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2693 | case float_round_nearest_even: |
| 2694 | if ( ( aExp == 0x3FFE ) && (bits64) ( extractFloatx80Frac( a )<<1 ) |
| 2695 | ) { |
| 2696 | return |
| 2697 | packFloatx80( aSign, 0x3FFF, LIT64( 0x8000000000000000 ) ); |
| 2698 | } |
| 2699 | break; |
| 2700 | case float_round_down: |
| 2701 | return |
| 2702 | aSign ? |
| 2703 | packFloatx80( 1, 0x3FFF, LIT64( 0x8000000000000000 ) ) |
| 2704 | : packFloatx80( 0, 0, 0 ); |
| 2705 | case float_round_up: |
| 2706 | return |
| 2707 | aSign ? packFloatx80( 1, 0, 0 ) |
| 2708 | : packFloatx80( 0, 0x3FFF, LIT64( 0x8000000000000000 ) ); |
| 2709 | } |
| 2710 | return packFloatx80( aSign, 0, 0 ); |
| 2711 | } |
| 2712 | lastBitMask = 1; |
| 2713 | lastBitMask <<= 0x403E - aExp; |
| 2714 | roundBitsMask = lastBitMask - 1; |
| 2715 | z = a; |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 2716 | roundingMode = roundData->mode; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2717 | if ( roundingMode == float_round_nearest_even ) { |
| 2718 | z.low += lastBitMask>>1; |
| 2719 | if ( ( z.low & roundBitsMask ) == 0 ) z.low &= ~ lastBitMask; |
| 2720 | } |
| 2721 | else if ( roundingMode != float_round_to_zero ) { |
| 2722 | if ( extractFloatx80Sign( z ) ^ ( roundingMode == float_round_up ) ) { |
| 2723 | z.low += roundBitsMask; |
| 2724 | } |
| 2725 | } |
| 2726 | z.low &= ~ roundBitsMask; |
| 2727 | if ( z.low == 0 ) { |
| 2728 | ++z.high; |
| 2729 | z.low = LIT64( 0x8000000000000000 ); |
| 2730 | } |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 2731 | if ( z.low != a.low ) roundData->exception |= float_flag_inexact; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2732 | return z; |
| 2733 | |
| 2734 | } |
| 2735 | |
| 2736 | /* |
| 2737 | ------------------------------------------------------------------------------- |
| 2738 | Returns the result of adding the absolute values of the extended double- |
| 2739 | precision floating-point values `a' and `b'. If `zSign' is true, the sum is |
| 2740 | negated before being returned. `zSign' is ignored if the result is a NaN. |
| 2741 | The addition is performed according to the IEC/IEEE Standard for Binary |
| 2742 | Floating-point Arithmetic. |
| 2743 | ------------------------------------------------------------------------------- |
| 2744 | */ |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 2745 | static floatx80 addFloatx80Sigs( struct roundingData *roundData, floatx80 a, floatx80 b, flag zSign ) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2746 | { |
| 2747 | int32 aExp, bExp, zExp; |
| 2748 | bits64 aSig, bSig, zSig0, zSig1; |
| 2749 | int32 expDiff; |
| 2750 | |
| 2751 | aSig = extractFloatx80Frac( a ); |
| 2752 | aExp = extractFloatx80Exp( a ); |
| 2753 | bSig = extractFloatx80Frac( b ); |
| 2754 | bExp = extractFloatx80Exp( b ); |
| 2755 | expDiff = aExp - bExp; |
| 2756 | if ( 0 < expDiff ) { |
| 2757 | if ( aExp == 0x7FFF ) { |
| 2758 | if ( (bits64) ( aSig<<1 ) ) return propagateFloatx80NaN( a, b ); |
| 2759 | return a; |
| 2760 | } |
| 2761 | if ( bExp == 0 ) --expDiff; |
| 2762 | shift64ExtraRightJamming( bSig, 0, expDiff, &bSig, &zSig1 ); |
| 2763 | zExp = aExp; |
| 2764 | } |
| 2765 | else if ( expDiff < 0 ) { |
| 2766 | if ( bExp == 0x7FFF ) { |
| 2767 | if ( (bits64) ( bSig<<1 ) ) return propagateFloatx80NaN( a, b ); |
| 2768 | return packFloatx80( zSign, 0x7FFF, LIT64( 0x8000000000000000 ) ); |
| 2769 | } |
| 2770 | if ( aExp == 0 ) ++expDiff; |
| 2771 | shift64ExtraRightJamming( aSig, 0, - expDiff, &aSig, &zSig1 ); |
| 2772 | zExp = bExp; |
| 2773 | } |
| 2774 | else { |
| 2775 | if ( aExp == 0x7FFF ) { |
| 2776 | if ( (bits64) ( ( aSig | bSig )<<1 ) ) { |
| 2777 | return propagateFloatx80NaN( a, b ); |
| 2778 | } |
| 2779 | return a; |
| 2780 | } |
| 2781 | zSig1 = 0; |
| 2782 | zSig0 = aSig + bSig; |
| 2783 | if ( aExp == 0 ) { |
| 2784 | normalizeFloatx80Subnormal( zSig0, &zExp, &zSig0 ); |
| 2785 | goto roundAndPack; |
| 2786 | } |
| 2787 | zExp = aExp; |
| 2788 | goto shiftRight1; |
| 2789 | } |
| 2790 | |
| 2791 | zSig0 = aSig + bSig; |
| 2792 | |
| 2793 | if ( (sbits64) zSig0 < 0 ) goto roundAndPack; |
| 2794 | shiftRight1: |
| 2795 | shift64ExtraRightJamming( zSig0, zSig1, 1, &zSig0, &zSig1 ); |
| 2796 | zSig0 |= LIT64( 0x8000000000000000 ); |
| 2797 | ++zExp; |
| 2798 | roundAndPack: |
| 2799 | return |
| 2800 | roundAndPackFloatx80( |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 2801 | roundData, zSign, zExp, zSig0, zSig1 ); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2802 | |
| 2803 | } |
| 2804 | |
| 2805 | /* |
| 2806 | ------------------------------------------------------------------------------- |
| 2807 | Returns the result of subtracting the absolute values of the extended |
| 2808 | double-precision floating-point values `a' and `b'. If `zSign' is true, |
| 2809 | the difference is negated before being returned. `zSign' is ignored if the |
| 2810 | result is a NaN. The subtraction is performed according to the IEC/IEEE |
| 2811 | Standard for Binary Floating-point Arithmetic. |
| 2812 | ------------------------------------------------------------------------------- |
| 2813 | */ |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 2814 | static floatx80 subFloatx80Sigs( struct roundingData *roundData, floatx80 a, floatx80 b, flag zSign ) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2815 | { |
| 2816 | int32 aExp, bExp, zExp; |
| 2817 | bits64 aSig, bSig, zSig0, zSig1; |
| 2818 | int32 expDiff; |
| 2819 | floatx80 z; |
| 2820 | |
| 2821 | aSig = extractFloatx80Frac( a ); |
| 2822 | aExp = extractFloatx80Exp( a ); |
| 2823 | bSig = extractFloatx80Frac( b ); |
| 2824 | bExp = extractFloatx80Exp( b ); |
| 2825 | expDiff = aExp - bExp; |
| 2826 | if ( 0 < expDiff ) goto aExpBigger; |
| 2827 | if ( expDiff < 0 ) goto bExpBigger; |
| 2828 | if ( aExp == 0x7FFF ) { |
| 2829 | if ( (bits64) ( ( aSig | bSig )<<1 ) ) { |
| 2830 | return propagateFloatx80NaN( a, b ); |
| 2831 | } |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 2832 | roundData->exception |= float_flag_invalid; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2833 | z.low = floatx80_default_nan_low; |
| 2834 | z.high = floatx80_default_nan_high; |
Lennert Buytenhek | 06c03ca | 2005-11-07 21:12:07 +0000 | [diff] [blame] | 2835 | z.__padding = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2836 | return z; |
| 2837 | } |
| 2838 | if ( aExp == 0 ) { |
| 2839 | aExp = 1; |
| 2840 | bExp = 1; |
| 2841 | } |
| 2842 | zSig1 = 0; |
| 2843 | if ( bSig < aSig ) goto aBigger; |
| 2844 | if ( aSig < bSig ) goto bBigger; |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 2845 | return packFloatx80( roundData->mode == float_round_down, 0, 0 ); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2846 | bExpBigger: |
| 2847 | if ( bExp == 0x7FFF ) { |
| 2848 | if ( (bits64) ( bSig<<1 ) ) return propagateFloatx80NaN( a, b ); |
| 2849 | return packFloatx80( zSign ^ 1, 0x7FFF, LIT64( 0x8000000000000000 ) ); |
| 2850 | } |
| 2851 | if ( aExp == 0 ) ++expDiff; |
| 2852 | shift128RightJamming( aSig, 0, - expDiff, &aSig, &zSig1 ); |
| 2853 | bBigger: |
| 2854 | sub128( bSig, 0, aSig, zSig1, &zSig0, &zSig1 ); |
| 2855 | zExp = bExp; |
| 2856 | zSign ^= 1; |
| 2857 | goto normalizeRoundAndPack; |
| 2858 | aExpBigger: |
| 2859 | if ( aExp == 0x7FFF ) { |
| 2860 | if ( (bits64) ( aSig<<1 ) ) return propagateFloatx80NaN( a, b ); |
| 2861 | return a; |
| 2862 | } |
| 2863 | if ( bExp == 0 ) --expDiff; |
| 2864 | shift128RightJamming( bSig, 0, expDiff, &bSig, &zSig1 ); |
| 2865 | aBigger: |
| 2866 | sub128( aSig, 0, bSig, zSig1, &zSig0, &zSig1 ); |
| 2867 | zExp = aExp; |
| 2868 | normalizeRoundAndPack: |
| 2869 | return |
| 2870 | normalizeRoundAndPackFloatx80( |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 2871 | roundData, zSign, zExp, zSig0, zSig1 ); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2872 | |
| 2873 | } |
| 2874 | |
| 2875 | /* |
| 2876 | ------------------------------------------------------------------------------- |
| 2877 | Returns the result of adding the extended double-precision floating-point |
| 2878 | values `a' and `b'. The operation is performed according to the IEC/IEEE |
| 2879 | Standard for Binary Floating-point Arithmetic. |
| 2880 | ------------------------------------------------------------------------------- |
| 2881 | */ |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 2882 | floatx80 floatx80_add( struct roundingData *roundData, floatx80 a, floatx80 b ) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2883 | { |
| 2884 | flag aSign, bSign; |
| 2885 | |
| 2886 | aSign = extractFloatx80Sign( a ); |
| 2887 | bSign = extractFloatx80Sign( b ); |
| 2888 | if ( aSign == bSign ) { |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 2889 | return addFloatx80Sigs( roundData, a, b, aSign ); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2890 | } |
| 2891 | else { |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 2892 | return subFloatx80Sigs( roundData, a, b, aSign ); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2893 | } |
| 2894 | |
| 2895 | } |
| 2896 | |
| 2897 | /* |
| 2898 | ------------------------------------------------------------------------------- |
| 2899 | Returns the result of subtracting the extended double-precision floating- |
| 2900 | point values `a' and `b'. The operation is performed according to the |
| 2901 | IEC/IEEE Standard for Binary Floating-point Arithmetic. |
| 2902 | ------------------------------------------------------------------------------- |
| 2903 | */ |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 2904 | floatx80 floatx80_sub( struct roundingData *roundData, floatx80 a, floatx80 b ) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2905 | { |
| 2906 | flag aSign, bSign; |
| 2907 | |
| 2908 | aSign = extractFloatx80Sign( a ); |
| 2909 | bSign = extractFloatx80Sign( b ); |
| 2910 | if ( aSign == bSign ) { |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 2911 | return subFloatx80Sigs( roundData, a, b, aSign ); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2912 | } |
| 2913 | else { |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 2914 | return addFloatx80Sigs( roundData, a, b, aSign ); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2915 | } |
| 2916 | |
| 2917 | } |
| 2918 | |
| 2919 | /* |
| 2920 | ------------------------------------------------------------------------------- |
| 2921 | Returns the result of multiplying the extended double-precision floating- |
| 2922 | point values `a' and `b'. The operation is performed according to the |
| 2923 | IEC/IEEE Standard for Binary Floating-point Arithmetic. |
| 2924 | ------------------------------------------------------------------------------- |
| 2925 | */ |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 2926 | floatx80 floatx80_mul( struct roundingData *roundData, floatx80 a, floatx80 b ) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2927 | { |
| 2928 | flag aSign, bSign, zSign; |
| 2929 | int32 aExp, bExp, zExp; |
| 2930 | bits64 aSig, bSig, zSig0, zSig1; |
| 2931 | floatx80 z; |
| 2932 | |
| 2933 | aSig = extractFloatx80Frac( a ); |
| 2934 | aExp = extractFloatx80Exp( a ); |
| 2935 | aSign = extractFloatx80Sign( a ); |
| 2936 | bSig = extractFloatx80Frac( b ); |
| 2937 | bExp = extractFloatx80Exp( b ); |
| 2938 | bSign = extractFloatx80Sign( b ); |
| 2939 | zSign = aSign ^ bSign; |
| 2940 | if ( aExp == 0x7FFF ) { |
| 2941 | if ( (bits64) ( aSig<<1 ) |
| 2942 | || ( ( bExp == 0x7FFF ) && (bits64) ( bSig<<1 ) ) ) { |
| 2943 | return propagateFloatx80NaN( a, b ); |
| 2944 | } |
| 2945 | if ( ( bExp | bSig ) == 0 ) goto invalid; |
| 2946 | return packFloatx80( zSign, 0x7FFF, LIT64( 0x8000000000000000 ) ); |
| 2947 | } |
| 2948 | if ( bExp == 0x7FFF ) { |
| 2949 | if ( (bits64) ( bSig<<1 ) ) return propagateFloatx80NaN( a, b ); |
| 2950 | if ( ( aExp | aSig ) == 0 ) { |
| 2951 | invalid: |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 2952 | roundData->exception |= float_flag_invalid; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2953 | z.low = floatx80_default_nan_low; |
| 2954 | z.high = floatx80_default_nan_high; |
Lennert Buytenhek | 06c03ca | 2005-11-07 21:12:07 +0000 | [diff] [blame] | 2955 | z.__padding = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2956 | return z; |
| 2957 | } |
| 2958 | return packFloatx80( zSign, 0x7FFF, LIT64( 0x8000000000000000 ) ); |
| 2959 | } |
| 2960 | if ( aExp == 0 ) { |
| 2961 | if ( aSig == 0 ) return packFloatx80( zSign, 0, 0 ); |
| 2962 | normalizeFloatx80Subnormal( aSig, &aExp, &aSig ); |
| 2963 | } |
| 2964 | if ( bExp == 0 ) { |
| 2965 | if ( bSig == 0 ) return packFloatx80( zSign, 0, 0 ); |
| 2966 | normalizeFloatx80Subnormal( bSig, &bExp, &bSig ); |
| 2967 | } |
| 2968 | zExp = aExp + bExp - 0x3FFE; |
| 2969 | mul64To128( aSig, bSig, &zSig0, &zSig1 ); |
| 2970 | if ( 0 < (sbits64) zSig0 ) { |
| 2971 | shortShift128Left( zSig0, zSig1, 1, &zSig0, &zSig1 ); |
| 2972 | --zExp; |
| 2973 | } |
| 2974 | return |
| 2975 | roundAndPackFloatx80( |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 2976 | roundData, zSign, zExp, zSig0, zSig1 ); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2977 | |
| 2978 | } |
| 2979 | |
| 2980 | /* |
| 2981 | ------------------------------------------------------------------------------- |
| 2982 | Returns the result of dividing the extended double-precision floating-point |
| 2983 | value `a' by the corresponding value `b'. The operation is performed |
| 2984 | according to the IEC/IEEE Standard for Binary Floating-point Arithmetic. |
| 2985 | ------------------------------------------------------------------------------- |
| 2986 | */ |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 2987 | floatx80 floatx80_div( struct roundingData *roundData, floatx80 a, floatx80 b ) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 2988 | { |
| 2989 | flag aSign, bSign, zSign; |
| 2990 | int32 aExp, bExp, zExp; |
| 2991 | bits64 aSig, bSig, zSig0, zSig1; |
| 2992 | bits64 rem0, rem1, rem2, term0, term1, term2; |
| 2993 | floatx80 z; |
| 2994 | |
| 2995 | aSig = extractFloatx80Frac( a ); |
| 2996 | aExp = extractFloatx80Exp( a ); |
| 2997 | aSign = extractFloatx80Sign( a ); |
| 2998 | bSig = extractFloatx80Frac( b ); |
| 2999 | bExp = extractFloatx80Exp( b ); |
| 3000 | bSign = extractFloatx80Sign( b ); |
| 3001 | zSign = aSign ^ bSign; |
| 3002 | if ( aExp == 0x7FFF ) { |
| 3003 | if ( (bits64) ( aSig<<1 ) ) return propagateFloatx80NaN( a, b ); |
| 3004 | if ( bExp == 0x7FFF ) { |
| 3005 | if ( (bits64) ( bSig<<1 ) ) return propagateFloatx80NaN( a, b ); |
| 3006 | goto invalid; |
| 3007 | } |
| 3008 | return packFloatx80( zSign, 0x7FFF, LIT64( 0x8000000000000000 ) ); |
| 3009 | } |
| 3010 | if ( bExp == 0x7FFF ) { |
| 3011 | if ( (bits64) ( bSig<<1 ) ) return propagateFloatx80NaN( a, b ); |
| 3012 | return packFloatx80( zSign, 0, 0 ); |
| 3013 | } |
| 3014 | if ( bExp == 0 ) { |
| 3015 | if ( bSig == 0 ) { |
| 3016 | if ( ( aExp | aSig ) == 0 ) { |
| 3017 | invalid: |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 3018 | roundData->exception |= float_flag_invalid; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3019 | z.low = floatx80_default_nan_low; |
| 3020 | z.high = floatx80_default_nan_high; |
Lennert Buytenhek | 06c03ca | 2005-11-07 21:12:07 +0000 | [diff] [blame] | 3021 | z.__padding = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3022 | return z; |
| 3023 | } |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 3024 | roundData->exception |= float_flag_divbyzero; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3025 | return packFloatx80( zSign, 0x7FFF, LIT64( 0x8000000000000000 ) ); |
| 3026 | } |
| 3027 | normalizeFloatx80Subnormal( bSig, &bExp, &bSig ); |
| 3028 | } |
| 3029 | if ( aExp == 0 ) { |
| 3030 | if ( aSig == 0 ) return packFloatx80( zSign, 0, 0 ); |
| 3031 | normalizeFloatx80Subnormal( aSig, &aExp, &aSig ); |
| 3032 | } |
| 3033 | zExp = aExp - bExp + 0x3FFE; |
| 3034 | rem1 = 0; |
| 3035 | if ( bSig <= aSig ) { |
| 3036 | shift128Right( aSig, 0, 1, &aSig, &rem1 ); |
| 3037 | ++zExp; |
| 3038 | } |
| 3039 | zSig0 = estimateDiv128To64( aSig, rem1, bSig ); |
| 3040 | mul64To128( bSig, zSig0, &term0, &term1 ); |
| 3041 | sub128( aSig, rem1, term0, term1, &rem0, &rem1 ); |
| 3042 | while ( (sbits64) rem0 < 0 ) { |
| 3043 | --zSig0; |
| 3044 | add128( rem0, rem1, 0, bSig, &rem0, &rem1 ); |
| 3045 | } |
| 3046 | zSig1 = estimateDiv128To64( rem1, 0, bSig ); |
| 3047 | if ( (bits64) ( zSig1<<1 ) <= 8 ) { |
| 3048 | mul64To128( bSig, zSig1, &term1, &term2 ); |
| 3049 | sub128( rem1, 0, term1, term2, &rem1, &rem2 ); |
| 3050 | while ( (sbits64) rem1 < 0 ) { |
| 3051 | --zSig1; |
| 3052 | add128( rem1, rem2, 0, bSig, &rem1, &rem2 ); |
| 3053 | } |
| 3054 | zSig1 |= ( ( rem1 | rem2 ) != 0 ); |
| 3055 | } |
| 3056 | return |
| 3057 | roundAndPackFloatx80( |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 3058 | roundData, zSign, zExp, zSig0, zSig1 ); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3059 | |
| 3060 | } |
| 3061 | |
| 3062 | /* |
| 3063 | ------------------------------------------------------------------------------- |
| 3064 | Returns the remainder of the extended double-precision floating-point value |
| 3065 | `a' with respect to the corresponding value `b'. The operation is performed |
| 3066 | according to the IEC/IEEE Standard for Binary Floating-point Arithmetic. |
| 3067 | ------------------------------------------------------------------------------- |
| 3068 | */ |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 3069 | floatx80 floatx80_rem( struct roundingData *roundData, floatx80 a, floatx80 b ) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3070 | { |
| 3071 | flag aSign, bSign, zSign; |
| 3072 | int32 aExp, bExp, expDiff; |
| 3073 | bits64 aSig0, aSig1, bSig; |
| 3074 | bits64 q, term0, term1, alternateASig0, alternateASig1; |
| 3075 | floatx80 z; |
| 3076 | |
| 3077 | aSig0 = extractFloatx80Frac( a ); |
| 3078 | aExp = extractFloatx80Exp( a ); |
| 3079 | aSign = extractFloatx80Sign( a ); |
| 3080 | bSig = extractFloatx80Frac( b ); |
| 3081 | bExp = extractFloatx80Exp( b ); |
| 3082 | bSign = extractFloatx80Sign( b ); |
| 3083 | if ( aExp == 0x7FFF ) { |
| 3084 | if ( (bits64) ( aSig0<<1 ) |
| 3085 | || ( ( bExp == 0x7FFF ) && (bits64) ( bSig<<1 ) ) ) { |
| 3086 | return propagateFloatx80NaN( a, b ); |
| 3087 | } |
| 3088 | goto invalid; |
| 3089 | } |
| 3090 | if ( bExp == 0x7FFF ) { |
| 3091 | if ( (bits64) ( bSig<<1 ) ) return propagateFloatx80NaN( a, b ); |
| 3092 | return a; |
| 3093 | } |
| 3094 | if ( bExp == 0 ) { |
| 3095 | if ( bSig == 0 ) { |
| 3096 | invalid: |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 3097 | roundData->exception |= float_flag_invalid; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3098 | z.low = floatx80_default_nan_low; |
| 3099 | z.high = floatx80_default_nan_high; |
Lennert Buytenhek | 06c03ca | 2005-11-07 21:12:07 +0000 | [diff] [blame] | 3100 | z.__padding = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3101 | return z; |
| 3102 | } |
| 3103 | normalizeFloatx80Subnormal( bSig, &bExp, &bSig ); |
| 3104 | } |
| 3105 | if ( aExp == 0 ) { |
| 3106 | if ( (bits64) ( aSig0<<1 ) == 0 ) return a; |
| 3107 | normalizeFloatx80Subnormal( aSig0, &aExp, &aSig0 ); |
| 3108 | } |
| 3109 | bSig |= LIT64( 0x8000000000000000 ); |
| 3110 | zSign = aSign; |
| 3111 | expDiff = aExp - bExp; |
| 3112 | aSig1 = 0; |
| 3113 | if ( expDiff < 0 ) { |
| 3114 | if ( expDiff < -1 ) return a; |
| 3115 | shift128Right( aSig0, 0, 1, &aSig0, &aSig1 ); |
| 3116 | expDiff = 0; |
| 3117 | } |
| 3118 | q = ( bSig <= aSig0 ); |
| 3119 | if ( q ) aSig0 -= bSig; |
| 3120 | expDiff -= 64; |
| 3121 | while ( 0 < expDiff ) { |
| 3122 | q = estimateDiv128To64( aSig0, aSig1, bSig ); |
| 3123 | q = ( 2 < q ) ? q - 2 : 0; |
| 3124 | mul64To128( bSig, q, &term0, &term1 ); |
| 3125 | sub128( aSig0, aSig1, term0, term1, &aSig0, &aSig1 ); |
| 3126 | shortShift128Left( aSig0, aSig1, 62, &aSig0, &aSig1 ); |
| 3127 | expDiff -= 62; |
| 3128 | } |
| 3129 | expDiff += 64; |
| 3130 | if ( 0 < expDiff ) { |
| 3131 | q = estimateDiv128To64( aSig0, aSig1, bSig ); |
| 3132 | q = ( 2 < q ) ? q - 2 : 0; |
| 3133 | q >>= 64 - expDiff; |
| 3134 | mul64To128( bSig, q<<( 64 - expDiff ), &term0, &term1 ); |
| 3135 | sub128( aSig0, aSig1, term0, term1, &aSig0, &aSig1 ); |
| 3136 | shortShift128Left( 0, bSig, 64 - expDiff, &term0, &term1 ); |
| 3137 | while ( le128( term0, term1, aSig0, aSig1 ) ) { |
| 3138 | ++q; |
| 3139 | sub128( aSig0, aSig1, term0, term1, &aSig0, &aSig1 ); |
| 3140 | } |
| 3141 | } |
| 3142 | else { |
| 3143 | term1 = 0; |
| 3144 | term0 = bSig; |
| 3145 | } |
| 3146 | sub128( term0, term1, aSig0, aSig1, &alternateASig0, &alternateASig1 ); |
| 3147 | if ( lt128( alternateASig0, alternateASig1, aSig0, aSig1 ) |
| 3148 | || ( eq128( alternateASig0, alternateASig1, aSig0, aSig1 ) |
| 3149 | && ( q & 1 ) ) |
| 3150 | ) { |
| 3151 | aSig0 = alternateASig0; |
| 3152 | aSig1 = alternateASig1; |
| 3153 | zSign = ! zSign; |
| 3154 | } |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 3155 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3156 | return |
| 3157 | normalizeRoundAndPackFloatx80( |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 3158 | roundData, zSign, bExp + expDiff, aSig0, aSig1 ); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3159 | |
| 3160 | } |
| 3161 | |
| 3162 | /* |
| 3163 | ------------------------------------------------------------------------------- |
| 3164 | Returns the square root of the extended double-precision floating-point |
| 3165 | value `a'. The operation is performed according to the IEC/IEEE Standard |
| 3166 | for Binary Floating-point Arithmetic. |
| 3167 | ------------------------------------------------------------------------------- |
| 3168 | */ |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 3169 | floatx80 floatx80_sqrt( struct roundingData *roundData, floatx80 a ) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3170 | { |
| 3171 | flag aSign; |
| 3172 | int32 aExp, zExp; |
| 3173 | bits64 aSig0, aSig1, zSig0, zSig1; |
| 3174 | bits64 rem0, rem1, rem2, rem3, term0, term1, term2, term3; |
| 3175 | bits64 shiftedRem0, shiftedRem1; |
| 3176 | floatx80 z; |
| 3177 | |
| 3178 | aSig0 = extractFloatx80Frac( a ); |
| 3179 | aExp = extractFloatx80Exp( a ); |
| 3180 | aSign = extractFloatx80Sign( a ); |
| 3181 | if ( aExp == 0x7FFF ) { |
| 3182 | if ( (bits64) ( aSig0<<1 ) ) return propagateFloatx80NaN( a, a ); |
| 3183 | if ( ! aSign ) return a; |
| 3184 | goto invalid; |
| 3185 | } |
| 3186 | if ( aSign ) { |
| 3187 | if ( ( aExp | aSig0 ) == 0 ) return a; |
| 3188 | invalid: |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 3189 | roundData->exception |= float_flag_invalid; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3190 | z.low = floatx80_default_nan_low; |
| 3191 | z.high = floatx80_default_nan_high; |
Lennert Buytenhek | 06c03ca | 2005-11-07 21:12:07 +0000 | [diff] [blame] | 3192 | z.__padding = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3193 | return z; |
| 3194 | } |
| 3195 | if ( aExp == 0 ) { |
| 3196 | if ( aSig0 == 0 ) return packFloatx80( 0, 0, 0 ); |
| 3197 | normalizeFloatx80Subnormal( aSig0, &aExp, &aSig0 ); |
| 3198 | } |
| 3199 | zExp = ( ( aExp - 0x3FFF )>>1 ) + 0x3FFF; |
| 3200 | zSig0 = estimateSqrt32( aExp, aSig0>>32 ); |
| 3201 | zSig0 <<= 31; |
| 3202 | aSig1 = 0; |
| 3203 | shift128Right( aSig0, 0, ( aExp & 1 ) + 2, &aSig0, &aSig1 ); |
| 3204 | zSig0 = estimateDiv128To64( aSig0, aSig1, zSig0 ) + zSig0 + 4; |
| 3205 | if ( 0 <= (sbits64) zSig0 ) zSig0 = LIT64( 0xFFFFFFFFFFFFFFFF ); |
| 3206 | shortShift128Left( aSig0, aSig1, 2, &aSig0, &aSig1 ); |
| 3207 | mul64To128( zSig0, zSig0, &term0, &term1 ); |
| 3208 | sub128( aSig0, aSig1, term0, term1, &rem0, &rem1 ); |
| 3209 | while ( (sbits64) rem0 < 0 ) { |
| 3210 | --zSig0; |
| 3211 | shortShift128Left( 0, zSig0, 1, &term0, &term1 ); |
| 3212 | term1 |= 1; |
| 3213 | add128( rem0, rem1, term0, term1, &rem0, &rem1 ); |
| 3214 | } |
| 3215 | shortShift128Left( rem0, rem1, 63, &shiftedRem0, &shiftedRem1 ); |
| 3216 | zSig1 = estimateDiv128To64( shiftedRem0, shiftedRem1, zSig0 ); |
| 3217 | if ( (bits64) ( zSig1<<1 ) <= 10 ) { |
| 3218 | if ( zSig1 == 0 ) zSig1 = 1; |
| 3219 | mul64To128( zSig0, zSig1, &term1, &term2 ); |
| 3220 | shortShift128Left( term1, term2, 1, &term1, &term2 ); |
| 3221 | sub128( rem1, 0, term1, term2, &rem1, &rem2 ); |
| 3222 | mul64To128( zSig1, zSig1, &term2, &term3 ); |
| 3223 | sub192( rem1, rem2, 0, 0, term2, term3, &rem1, &rem2, &rem3 ); |
| 3224 | while ( (sbits64) rem1 < 0 ) { |
| 3225 | --zSig1; |
| 3226 | shortShift192Left( 0, zSig0, zSig1, 1, &term1, &term2, &term3 ); |
| 3227 | term3 |= 1; |
| 3228 | add192( |
| 3229 | rem1, rem2, rem3, term1, term2, term3, &rem1, &rem2, &rem3 ); |
| 3230 | } |
| 3231 | zSig1 |= ( ( rem1 | rem2 | rem3 ) != 0 ); |
| 3232 | } |
| 3233 | return |
| 3234 | roundAndPackFloatx80( |
Richard Purdie | f148af2 | 2005-08-03 19:49:17 +0100 | [diff] [blame] | 3235 | roundData, 0, zExp, zSig0, zSig1 ); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3236 | |
| 3237 | } |
| 3238 | |
| 3239 | /* |
| 3240 | ------------------------------------------------------------------------------- |
| 3241 | Returns 1 if the extended double-precision floating-point value `a' is |
| 3242 | equal to the corresponding value `b', and 0 otherwise. The comparison is |
| 3243 | performed according to the IEC/IEEE Standard for Binary Floating-point |
| 3244 | Arithmetic. |
| 3245 | ------------------------------------------------------------------------------- |
| 3246 | */ |
| 3247 | flag floatx80_eq( floatx80 a, floatx80 b ) |
| 3248 | { |
| 3249 | |
| 3250 | if ( ( ( extractFloatx80Exp( a ) == 0x7FFF ) |
| 3251 | && (bits64) ( extractFloatx80Frac( a )<<1 ) ) |
| 3252 | || ( ( extractFloatx80Exp( b ) == 0x7FFF ) |
| 3253 | && (bits64) ( extractFloatx80Frac( b )<<1 ) ) |
| 3254 | ) { |
| 3255 | if ( floatx80_is_signaling_nan( a ) |
| 3256 | || floatx80_is_signaling_nan( b ) ) { |
Richard Purdie | 54738e8 | 2005-08-15 20:42:32 +0100 | [diff] [blame] | 3257 | float_raise( float_flag_invalid ); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3258 | } |
| 3259 | return 0; |
| 3260 | } |
| 3261 | return |
| 3262 | ( a.low == b.low ) |
| 3263 | && ( ( a.high == b.high ) |
| 3264 | || ( ( a.low == 0 ) |
| 3265 | && ( (bits16) ( ( a.high | b.high )<<1 ) == 0 ) ) |
| 3266 | ); |
| 3267 | |
| 3268 | } |
| 3269 | |
| 3270 | /* |
| 3271 | ------------------------------------------------------------------------------- |
| 3272 | Returns 1 if the extended double-precision floating-point value `a' is |
| 3273 | less than or equal to the corresponding value `b', and 0 otherwise. The |
| 3274 | comparison is performed according to the IEC/IEEE Standard for Binary |
| 3275 | Floating-point Arithmetic. |
| 3276 | ------------------------------------------------------------------------------- |
| 3277 | */ |
| 3278 | flag floatx80_le( floatx80 a, floatx80 b ) |
| 3279 | { |
| 3280 | flag aSign, bSign; |
| 3281 | |
| 3282 | if ( ( ( extractFloatx80Exp( a ) == 0x7FFF ) |
| 3283 | && (bits64) ( extractFloatx80Frac( a )<<1 ) ) |
| 3284 | || ( ( extractFloatx80Exp( b ) == 0x7FFF ) |
| 3285 | && (bits64) ( extractFloatx80Frac( b )<<1 ) ) |
| 3286 | ) { |
Richard Purdie | 54738e8 | 2005-08-15 20:42:32 +0100 | [diff] [blame] | 3287 | float_raise( float_flag_invalid ); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3288 | return 0; |
| 3289 | } |
| 3290 | aSign = extractFloatx80Sign( a ); |
| 3291 | bSign = extractFloatx80Sign( b ); |
| 3292 | if ( aSign != bSign ) { |
| 3293 | return |
| 3294 | aSign |
| 3295 | || ( ( ( (bits16) ( ( a.high | b.high )<<1 ) ) | a.low | b.low ) |
| 3296 | == 0 ); |
| 3297 | } |
| 3298 | return |
| 3299 | aSign ? le128( b.high, b.low, a.high, a.low ) |
| 3300 | : le128( a.high, a.low, b.high, b.low ); |
| 3301 | |
| 3302 | } |
| 3303 | |
| 3304 | /* |
| 3305 | ------------------------------------------------------------------------------- |
| 3306 | Returns 1 if the extended double-precision floating-point value `a' is |
| 3307 | less than the corresponding value `b', and 0 otherwise. The comparison |
| 3308 | is performed according to the IEC/IEEE Standard for Binary Floating-point |
| 3309 | Arithmetic. |
| 3310 | ------------------------------------------------------------------------------- |
| 3311 | */ |
| 3312 | flag floatx80_lt( floatx80 a, floatx80 b ) |
| 3313 | { |
| 3314 | flag aSign, bSign; |
| 3315 | |
| 3316 | if ( ( ( extractFloatx80Exp( a ) == 0x7FFF ) |
| 3317 | && (bits64) ( extractFloatx80Frac( a )<<1 ) ) |
| 3318 | || ( ( extractFloatx80Exp( b ) == 0x7FFF ) |
| 3319 | && (bits64) ( extractFloatx80Frac( b )<<1 ) ) |
| 3320 | ) { |
Richard Purdie | 54738e8 | 2005-08-15 20:42:32 +0100 | [diff] [blame] | 3321 | float_raise( float_flag_invalid ); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3322 | return 0; |
| 3323 | } |
| 3324 | aSign = extractFloatx80Sign( a ); |
| 3325 | bSign = extractFloatx80Sign( b ); |
| 3326 | if ( aSign != bSign ) { |
| 3327 | return |
| 3328 | aSign |
| 3329 | && ( ( ( (bits16) ( ( a.high | b.high )<<1 ) ) | a.low | b.low ) |
| 3330 | != 0 ); |
| 3331 | } |
| 3332 | return |
| 3333 | aSign ? lt128( b.high, b.low, a.high, a.low ) |
| 3334 | : lt128( a.high, a.low, b.high, b.low ); |
| 3335 | |
| 3336 | } |
| 3337 | |
| 3338 | /* |
| 3339 | ------------------------------------------------------------------------------- |
| 3340 | Returns 1 if the extended double-precision floating-point value `a' is equal |
| 3341 | to the corresponding value `b', and 0 otherwise. The invalid exception is |
| 3342 | raised if either operand is a NaN. Otherwise, the comparison is performed |
| 3343 | according to the IEC/IEEE Standard for Binary Floating-point Arithmetic. |
| 3344 | ------------------------------------------------------------------------------- |
| 3345 | */ |
| 3346 | flag floatx80_eq_signaling( floatx80 a, floatx80 b ) |
| 3347 | { |
| 3348 | |
| 3349 | if ( ( ( extractFloatx80Exp( a ) == 0x7FFF ) |
| 3350 | && (bits64) ( extractFloatx80Frac( a )<<1 ) ) |
| 3351 | || ( ( extractFloatx80Exp( b ) == 0x7FFF ) |
| 3352 | && (bits64) ( extractFloatx80Frac( b )<<1 ) ) |
| 3353 | ) { |
Richard Purdie | 54738e8 | 2005-08-15 20:42:32 +0100 | [diff] [blame] | 3354 | float_raise( float_flag_invalid ); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3355 | return 0; |
| 3356 | } |
| 3357 | return |
| 3358 | ( a.low == b.low ) |
| 3359 | && ( ( a.high == b.high ) |
| 3360 | || ( ( a.low == 0 ) |
| 3361 | && ( (bits16) ( ( a.high | b.high )<<1 ) == 0 ) ) |
| 3362 | ); |
| 3363 | |
| 3364 | } |
| 3365 | |
| 3366 | /* |
| 3367 | ------------------------------------------------------------------------------- |
| 3368 | Returns 1 if the extended double-precision floating-point value `a' is less |
| 3369 | than or equal to the corresponding value `b', and 0 otherwise. Quiet NaNs |
| 3370 | do not cause an exception. Otherwise, the comparison is performed according |
| 3371 | to the IEC/IEEE Standard for Binary Floating-point Arithmetic. |
| 3372 | ------------------------------------------------------------------------------- |
| 3373 | */ |
| 3374 | flag floatx80_le_quiet( floatx80 a, floatx80 b ) |
| 3375 | { |
| 3376 | flag aSign, bSign; |
| 3377 | |
| 3378 | if ( ( ( extractFloatx80Exp( a ) == 0x7FFF ) |
| 3379 | && (bits64) ( extractFloatx80Frac( a )<<1 ) ) |
| 3380 | || ( ( extractFloatx80Exp( b ) == 0x7FFF ) |
| 3381 | && (bits64) ( extractFloatx80Frac( b )<<1 ) ) |
| 3382 | ) { |
Richard Purdie | 54738e8 | 2005-08-15 20:42:32 +0100 | [diff] [blame] | 3383 | /* Do nothing, even if NaN as we're quiet */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3384 | return 0; |
| 3385 | } |
| 3386 | aSign = extractFloatx80Sign( a ); |
| 3387 | bSign = extractFloatx80Sign( b ); |
| 3388 | if ( aSign != bSign ) { |
| 3389 | return |
| 3390 | aSign |
| 3391 | || ( ( ( (bits16) ( ( a.high | b.high )<<1 ) ) | a.low | b.low ) |
| 3392 | == 0 ); |
| 3393 | } |
| 3394 | return |
| 3395 | aSign ? le128( b.high, b.low, a.high, a.low ) |
| 3396 | : le128( a.high, a.low, b.high, b.low ); |
| 3397 | |
| 3398 | } |
| 3399 | |
| 3400 | /* |
| 3401 | ------------------------------------------------------------------------------- |
| 3402 | Returns 1 if the extended double-precision floating-point value `a' is less |
| 3403 | than the corresponding value `b', and 0 otherwise. Quiet NaNs do not cause |
| 3404 | an exception. Otherwise, the comparison is performed according to the |
| 3405 | IEC/IEEE Standard for Binary Floating-point Arithmetic. |
| 3406 | ------------------------------------------------------------------------------- |
| 3407 | */ |
| 3408 | flag floatx80_lt_quiet( floatx80 a, floatx80 b ) |
| 3409 | { |
| 3410 | flag aSign, bSign; |
| 3411 | |
| 3412 | if ( ( ( extractFloatx80Exp( a ) == 0x7FFF ) |
| 3413 | && (bits64) ( extractFloatx80Frac( a )<<1 ) ) |
| 3414 | || ( ( extractFloatx80Exp( b ) == 0x7FFF ) |
| 3415 | && (bits64) ( extractFloatx80Frac( b )<<1 ) ) |
| 3416 | ) { |
Richard Purdie | 54738e8 | 2005-08-15 20:42:32 +0100 | [diff] [blame] | 3417 | /* Do nothing, even if NaN as we're quiet */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 3418 | return 0; |
| 3419 | } |
| 3420 | aSign = extractFloatx80Sign( a ); |
| 3421 | bSign = extractFloatx80Sign( b ); |
| 3422 | if ( aSign != bSign ) { |
| 3423 | return |
| 3424 | aSign |
| 3425 | && ( ( ( (bits16) ( ( a.high | b.high )<<1 ) ) | a.low | b.low ) |
| 3426 | != 0 ); |
| 3427 | } |
| 3428 | return |
| 3429 | aSign ? lt128( b.high, b.low, a.high, a.low ) |
| 3430 | : lt128( a.high, a.low, b.high, b.low ); |
| 3431 | |
| 3432 | } |
| 3433 | |
| 3434 | #endif |
| 3435 | |