1 // SPDX-License-Identifier: GPL-2.0 2 /*---------------------------------------------------------------------------+ 3 | reg_ld_str.c | 4 | | 5 | All of the functions which transfer data between user memory and FPU_REGs.| 6 | | 7 | Copyright (C) 1992,1993,1994,1996,1997 | 8 | W. Metzenthen, 22 Parker St, Ormond, Vic 3163, Australia | 9 | E-mail billm@suburbia.net | 10 | | 11 | | 12 +---------------------------------------------------------------------------*/ 13 14 /*---------------------------------------------------------------------------+ 15 | Note: | 16 | The file contains code which accesses user memory. | 17 | Emulator static data may change when user memory is accessed, due to | 18 | other processes using the emulator while swapping is in progress. | 19 +---------------------------------------------------------------------------*/ 20 21 #include "fpu_emu.h" 22 23 #include <linux/uaccess.h> 24 25 #include "fpu_system.h" 26 #include "exception.h" 27 #include "reg_constant.h" 28 #include "control_w.h" 29 #include "status_w.h" 30 31 #define DOUBLE_Emax 1023 /* largest valid exponent */ 32 #define DOUBLE_Ebias 1023 33 #define DOUBLE_Emin (-1022) /* smallest valid exponent */ 34 35 #define SINGLE_Emax 127 /* largest valid exponent */ 36 #define SINGLE_Ebias 127 37 #define SINGLE_Emin (-126) /* smallest valid exponent */ 38 39 static u_char normalize_no_excep(FPU_REG *r, int exp, int sign) 40 { 41 u_char tag; 42 43 setexponent16(r, exp); 44 45 tag = FPU_normalize_nuo(r); 46 stdexp(r); 47 if (sign) 48 setnegative(r); 49 50 return tag; 51 } 52 53 int FPU_tagof(FPU_REG *ptr) 54 { 55 int exp; 56 57 exp = exponent16(ptr) & 0x7fff; 58 if (exp == 0) { 59 if (!(ptr->sigh | ptr->sigl)) { 60 return TAG_Zero; 61 } 62 /* The number is a de-normal or pseudodenormal. */ 63 return TAG_Special; 64 } 65 66 if (exp == 0x7fff) { 67 /* Is an Infinity, a NaN, or an unsupported data type. */ 68 return TAG_Special; 69 } 70 71 if (!(ptr->sigh & 0x80000000)) { 72 /* Unsupported data type. */ 73 /* Valid numbers have the ms bit set to 1. */ 74 /* Unnormal. */ 75 return TAG_Special; 76 } 77 78 return TAG_Valid; 79 } 80 81 /* Get a long double from user memory */ 82 int FPU_load_extended(long double __user *s, int stnr) 83 { 84 FPU_REG *sti_ptr = &st(stnr); 85 86 RE_ENTRANT_CHECK_OFF; 87 FPU_access_ok(s, 10); 88 FPU_copy_from_user(sti_ptr, s, 10); 89 RE_ENTRANT_CHECK_ON; 90 91 return FPU_tagof(sti_ptr); 92 } 93 94 /* Get a double from user memory */ 95 int FPU_load_double(double __user *dfloat, FPU_REG *loaded_data) 96 { 97 int exp, tag, negative; 98 unsigned m64, l64; 99 100 RE_ENTRANT_CHECK_OFF; 101 FPU_access_ok(dfloat, 8); 102 FPU_get_user(m64, 1 + (unsigned long __user *)dfloat); 103 FPU_get_user(l64, (unsigned long __user *)dfloat); 104 RE_ENTRANT_CHECK_ON; 105 106 negative = (m64 & 0x80000000) ? SIGN_Negative : SIGN_Positive; 107 exp = ((m64 & 0x7ff00000) >> 20) - DOUBLE_Ebias + EXTENDED_Ebias; 108 m64 &= 0xfffff; 109 if (exp > DOUBLE_Emax + EXTENDED_Ebias) { 110 /* Infinity or NaN */ 111 if ((m64 == 0) && (l64 == 0)) { 112 /* +- infinity */ 113 loaded_data->sigh = 0x80000000; 114 loaded_data->sigl = 0x00000000; 115 exp = EXP_Infinity + EXTENDED_Ebias; 116 tag = TAG_Special; 117 } else { 118 /* Must be a signaling or quiet NaN */ 119 exp = EXP_NaN + EXTENDED_Ebias; 120 loaded_data->sigh = (m64 << 11) | 0x80000000; 121 loaded_data->sigh |= l64 >> 21; 122 loaded_data->sigl = l64 << 11; 123 tag = TAG_Special; /* The calling function must look for NaNs */ 124 } 125 } else if (exp < DOUBLE_Emin + EXTENDED_Ebias) { 126 /* Zero or de-normal */ 127 if ((m64 == 0) && (l64 == 0)) { 128 /* Zero */ 129 reg_copy(&CONST_Z, loaded_data); 130 exp = 0; 131 tag = TAG_Zero; 132 } else { 133 /* De-normal */ 134 loaded_data->sigh = m64 << 11; 135 loaded_data->sigh |= l64 >> 21; 136 loaded_data->sigl = l64 << 11; 137 138 return normalize_no_excep(loaded_data, DOUBLE_Emin, 139 negative) 140 | (denormal_operand() < 0 ? FPU_Exception : 0); 141 } 142 } else { 143 loaded_data->sigh = (m64 << 11) | 0x80000000; 144 loaded_data->sigh |= l64 >> 21; 145 loaded_data->sigl = l64 << 11; 146 147 tag = TAG_Valid; 148 } 149 150 setexponent16(loaded_data, exp | negative); 151 152 return tag; 153 } 154 155 /* Get a float from user memory */ 156 int FPU_load_single(float __user *single, FPU_REG *loaded_data) 157 { 158 unsigned m32; 159 int exp, tag, negative; 160 161 RE_ENTRANT_CHECK_OFF; 162 FPU_access_ok(single, 4); 163 FPU_get_user(m32, (unsigned long __user *)single); 164 RE_ENTRANT_CHECK_ON; 165 166 negative = (m32 & 0x80000000) ? SIGN_Negative : SIGN_Positive; 167 168 if (!(m32 & 0x7fffffff)) { 169 /* Zero */ 170 reg_copy(&CONST_Z, loaded_data); 171 addexponent(loaded_data, negative); 172 return TAG_Zero; 173 } 174 exp = ((m32 & 0x7f800000) >> 23) - SINGLE_Ebias + EXTENDED_Ebias; 175 m32 = (m32 & 0x7fffff) << 8; 176 if (exp < SINGLE_Emin + EXTENDED_Ebias) { 177 /* De-normals */ 178 loaded_data->sigh = m32; 179 loaded_data->sigl = 0; 180 181 return normalize_no_excep(loaded_data, SINGLE_Emin, negative) 182 | (denormal_operand() < 0 ? FPU_Exception : 0); 183 } else if (exp > SINGLE_Emax + EXTENDED_Ebias) { 184 /* Infinity or NaN */ 185 if (m32 == 0) { 186 /* +- infinity */ 187 loaded_data->sigh = 0x80000000; 188 loaded_data->sigl = 0x00000000; 189 exp = EXP_Infinity + EXTENDED_Ebias; 190 tag = TAG_Special; 191 } else { 192 /* Must be a signaling or quiet NaN */ 193 exp = EXP_NaN + EXTENDED_Ebias; 194 loaded_data->sigh = m32 | 0x80000000; 195 loaded_data->sigl = 0; 196 tag = TAG_Special; /* The calling function must look for NaNs */ 197 } 198 } else { 199 loaded_data->sigh = m32 | 0x80000000; 200 loaded_data->sigl = 0; 201 tag = TAG_Valid; 202 } 203 204 setexponent16(loaded_data, exp | negative); /* Set the sign. */ 205 206 return tag; 207 } 208 209 /* Get a long long from user memory */ 210 int FPU_load_int64(long long __user *_s) 211 { 212 long long s; 213 int sign; 214 FPU_REG *st0_ptr = &st(0); 215 216 RE_ENTRANT_CHECK_OFF; 217 FPU_access_ok(_s, 8); 218 if (copy_from_user(&s, _s, 8)) 219 FPU_abort; 220 RE_ENTRANT_CHECK_ON; 221 222 if (s == 0) { 223 reg_copy(&CONST_Z, st0_ptr); 224 return TAG_Zero; 225 } 226 227 if (s > 0) 228 sign = SIGN_Positive; 229 else { 230 s = -s; 231 sign = SIGN_Negative; 232 } 233 234 significand(st0_ptr) = s; 235 236 return normalize_no_excep(st0_ptr, 63, sign); 237 } 238 239 /* Get a long from user memory */ 240 int FPU_load_int32(long __user *_s, FPU_REG *loaded_data) 241 { 242 long s; 243 int negative; 244 245 RE_ENTRANT_CHECK_OFF; 246 FPU_access_ok(_s, 4); 247 FPU_get_user(s, _s); 248 RE_ENTRANT_CHECK_ON; 249 250 if (s == 0) { 251 reg_copy(&CONST_Z, loaded_data); 252 return TAG_Zero; 253 } 254 255 if (s > 0) 256 negative = SIGN_Positive; 257 else { 258 s = -s; 259 negative = SIGN_Negative; 260 } 261 262 loaded_data->sigh = s; 263 loaded_data->sigl = 0; 264 265 return normalize_no_excep(loaded_data, 31, negative); 266 } 267 268 /* Get a short from user memory */ 269 int FPU_load_int16(short __user *_s, FPU_REG *loaded_data) 270 { 271 int s, negative; 272 273 RE_ENTRANT_CHECK_OFF; 274 FPU_access_ok(_s, 2); 275 /* Cast as short to get the sign extended. */ 276 FPU_get_user(s, _s); 277 RE_ENTRANT_CHECK_ON; 278 279 if (s == 0) { 280 reg_copy(&CONST_Z, loaded_data); 281 return TAG_Zero; 282 } 283 284 if (s > 0) 285 negative = SIGN_Positive; 286 else { 287 s = -s; 288 negative = SIGN_Negative; 289 } 290 291 loaded_data->sigh = s << 16; 292 loaded_data->sigl = 0; 293 294 return normalize_no_excep(loaded_data, 15, negative); 295 } 296 297 /* Get a packed bcd array from user memory */ 298 int FPU_load_bcd(u_char __user *s) 299 { 300 FPU_REG *st0_ptr = &st(0); 301 int pos; 302 u_char bcd; 303 long long l = 0; 304 int sign; 305 306 RE_ENTRANT_CHECK_OFF; 307 FPU_access_ok(s, 10); 308 RE_ENTRANT_CHECK_ON; 309 for (pos = 8; pos >= 0; pos--) { 310 l *= 10; 311 RE_ENTRANT_CHECK_OFF; 312 FPU_get_user(bcd, s + pos); 313 RE_ENTRANT_CHECK_ON; 314 l += bcd >> 4; 315 l *= 10; 316 l += bcd & 0x0f; 317 } 318 319 RE_ENTRANT_CHECK_OFF; 320 FPU_get_user(sign, s + 9); 321 sign = sign & 0x80 ? SIGN_Negative : SIGN_Positive; 322 RE_ENTRANT_CHECK_ON; 323 324 if (l == 0) { 325 reg_copy(&CONST_Z, st0_ptr); 326 addexponent(st0_ptr, sign); /* Set the sign. */ 327 return TAG_Zero; 328 } else { 329 significand(st0_ptr) = l; 330 return normalize_no_excep(st0_ptr, 63, sign); 331 } 332 } 333 334 /*===========================================================================*/ 335 336 /* Put a long double into user memory */ 337 int FPU_store_extended(FPU_REG *st0_ptr, u_char st0_tag, 338 long double __user * d) 339 { 340 /* 341 The only exception raised by an attempt to store to an 342 extended format is the Invalid Stack exception, i.e. 343 attempting to store from an empty register. 344 */ 345 346 if (st0_tag != TAG_Empty) { 347 RE_ENTRANT_CHECK_OFF; 348 FPU_access_ok(d, 10); 349 350 FPU_put_user(st0_ptr->sigl, (unsigned long __user *)d); 351 FPU_put_user(st0_ptr->sigh, 352 (unsigned long __user *)((u_char __user *) d + 4)); 353 FPU_put_user(exponent16(st0_ptr), 354 (unsigned short __user *)((u_char __user *) d + 355 8)); 356 RE_ENTRANT_CHECK_ON; 357 358 return 1; 359 } 360 361 /* Empty register (stack underflow) */ 362 EXCEPTION(EX_StackUnder); 363 if (control_word & CW_Invalid) { 364 /* The masked response */ 365 /* Put out the QNaN indefinite */ 366 RE_ENTRANT_CHECK_OFF; 367 FPU_access_ok(d, 10); 368 FPU_put_user(0, (unsigned long __user *)d); 369 FPU_put_user(0xc0000000, 1 + (unsigned long __user *)d); 370 FPU_put_user(0xffff, 4 + (short __user *)d); 371 RE_ENTRANT_CHECK_ON; 372 return 1; 373 } else 374 return 0; 375 376 } 377 378 /* Put a double into user memory */ 379 int FPU_store_double(FPU_REG *st0_ptr, u_char st0_tag, double __user *dfloat) 380 { 381 unsigned long l[2]; 382 unsigned long increment = 0; /* avoid gcc warnings */ 383 int precision_loss; 384 int exp; 385 FPU_REG tmp; 386 387 l[0] = 0; 388 l[1] = 0; 389 if (st0_tag == TAG_Valid) { 390 reg_copy(st0_ptr, &tmp); 391 exp = exponent(&tmp); 392 393 if (exp < DOUBLE_Emin) { /* It may be a denormal */ 394 addexponent(&tmp, -DOUBLE_Emin + 52); /* largest exp to be 51 */ 395 denormal_arg: 396 if ((precision_loss = FPU_round_to_int(&tmp, st0_tag))) { 397 #ifdef PECULIAR_486 398 /* Did it round to a non-denormal ? */ 399 /* This behaviour might be regarded as peculiar, it appears 400 that the 80486 rounds to the dest precision, then 401 converts to decide underflow. */ 402 if (! 403 ((tmp.sigh == 0x00100000) && (tmp.sigl == 0) 404 && (st0_ptr->sigl & 0x000007ff))) 405 #endif /* PECULIAR_486 */ 406 { 407 EXCEPTION(EX_Underflow); 408 /* This is a special case: see sec 16.2.5.1 of 409 the 80486 book */ 410 if (!(control_word & CW_Underflow)) 411 return 0; 412 } 413 EXCEPTION(precision_loss); 414 if (!(control_word & CW_Precision)) 415 return 0; 416 } 417 l[0] = tmp.sigl; 418 l[1] = tmp.sigh; 419 } else { 420 if (tmp.sigl & 0x000007ff) { 421 precision_loss = 1; 422 switch (control_word & CW_RC) { 423 case RC_RND: 424 /* Rounding can get a little messy.. */ 425 increment = ((tmp.sigl & 0x7ff) > 0x400) | /* nearest */ 426 ((tmp.sigl & 0xc00) == 0xc00); /* odd -> even */ 427 break; 428 case RC_DOWN: /* towards -infinity */ 429 increment = 430 signpositive(&tmp) ? 0 : tmp. 431 sigl & 0x7ff; 432 break; 433 case RC_UP: /* towards +infinity */ 434 increment = 435 signpositive(&tmp) ? tmp. 436 sigl & 0x7ff : 0; 437 break; 438 case RC_CHOP: 439 increment = 0; 440 break; 441 } 442 443 /* Truncate the mantissa */ 444 tmp.sigl &= 0xfffff800; 445 446 if (increment) { 447 if (tmp.sigl >= 0xfffff800) { 448 /* the sigl part overflows */ 449 if (tmp.sigh == 0xffffffff) { 450 /* The sigh part overflows */ 451 tmp.sigh = 0x80000000; 452 exp++; 453 if (exp >= EXP_OVER) 454 goto overflow; 455 } else { 456 tmp.sigh++; 457 } 458 tmp.sigl = 0x00000000; 459 } else { 460 /* We only need to increment sigl */ 461 tmp.sigl += 0x00000800; 462 } 463 } 464 } else 465 precision_loss = 0; 466 467 l[0] = (tmp.sigl >> 11) | (tmp.sigh << 21); 468 l[1] = ((tmp.sigh >> 11) & 0xfffff); 469 470 if (exp > DOUBLE_Emax) { 471 overflow: 472 EXCEPTION(EX_Overflow); 473 if (!(control_word & CW_Overflow)) 474 return 0; 475 set_precision_flag_up(); 476 if (!(control_word & CW_Precision)) 477 return 0; 478 479 /* This is a special case: see sec 16.2.5.1 of the 80486 book */ 480 /* Overflow to infinity */ 481 l[1] = 0x7ff00000; /* Set to + INF */ 482 } else { 483 if (precision_loss) { 484 if (increment) 485 set_precision_flag_up(); 486 else 487 set_precision_flag_down(); 488 } 489 /* Add the exponent */ 490 l[1] |= (((exp + DOUBLE_Ebias) & 0x7ff) << 20); 491 } 492 } 493 } else if (st0_tag == TAG_Zero) { 494 /* Number is zero */ 495 } else if (st0_tag == TAG_Special) { 496 st0_tag = FPU_Special(st0_ptr); 497 if (st0_tag == TW_Denormal) { 498 /* A denormal will always underflow. */ 499 #ifndef PECULIAR_486 500 /* An 80486 is supposed to be able to generate 501 a denormal exception here, but... */ 502 /* Underflow has priority. */ 503 if (control_word & CW_Underflow) 504 denormal_operand(); 505 #endif /* PECULIAR_486 */ 506 reg_copy(st0_ptr, &tmp); 507 goto denormal_arg; 508 } else if (st0_tag == TW_Infinity) { 509 l[1] = 0x7ff00000; 510 } else if (st0_tag == TW_NaN) { 511 /* Is it really a NaN ? */ 512 if ((exponent(st0_ptr) == EXP_OVER) 513 && (st0_ptr->sigh & 0x80000000)) { 514 /* See if we can get a valid NaN from the FPU_REG */ 515 l[0] = 516 (st0_ptr->sigl >> 11) | (st0_ptr-> 517 sigh << 21); 518 l[1] = ((st0_ptr->sigh >> 11) & 0xfffff); 519 if (!(st0_ptr->sigh & 0x40000000)) { 520 /* It is a signalling NaN */ 521 EXCEPTION(EX_Invalid); 522 if (!(control_word & CW_Invalid)) 523 return 0; 524 l[1] |= (0x40000000 >> 11); 525 } 526 l[1] |= 0x7ff00000; 527 } else { 528 /* It is an unsupported data type */ 529 EXCEPTION(EX_Invalid); 530 if (!(control_word & CW_Invalid)) 531 return 0; 532 l[1] = 0xfff80000; 533 } 534 } 535 } else if (st0_tag == TAG_Empty) { 536 /* Empty register (stack underflow) */ 537 EXCEPTION(EX_StackUnder); 538 if (control_word & CW_Invalid) { 539 /* The masked response */ 540 /* Put out the QNaN indefinite */ 541 RE_ENTRANT_CHECK_OFF; 542 FPU_access_ok(dfloat, 8); 543 FPU_put_user(0, (unsigned long __user *)dfloat); 544 FPU_put_user(0xfff80000, 545 1 + (unsigned long __user *)dfloat); 546 RE_ENTRANT_CHECK_ON; 547 return 1; 548 } else 549 return 0; 550 } 551 if (getsign(st0_ptr)) 552 l[1] |= 0x80000000; 553 554 RE_ENTRANT_CHECK_OFF; 555 FPU_access_ok(dfloat, 8); 556 FPU_put_user(l[0], (unsigned long __user *)dfloat); 557 FPU_put_user(l[1], 1 + (unsigned long __user *)dfloat); 558 RE_ENTRANT_CHECK_ON; 559 560 return 1; 561 } 562 563 /* Put a float into user memory */ 564 int FPU_store_single(FPU_REG *st0_ptr, u_char st0_tag, float __user *single) 565 { 566 long templ = 0; 567 unsigned long increment = 0; /* avoid gcc warnings */ 568 int precision_loss; 569 int exp; 570 FPU_REG tmp; 571 572 if (st0_tag == TAG_Valid) { 573 574 reg_copy(st0_ptr, &tmp); 575 exp = exponent(&tmp); 576 577 if (exp < SINGLE_Emin) { 578 addexponent(&tmp, -SINGLE_Emin + 23); /* largest exp to be 22 */ 579 580 denormal_arg: 581 582 if ((precision_loss = FPU_round_to_int(&tmp, st0_tag))) { 583 #ifdef PECULIAR_486 584 /* Did it round to a non-denormal ? */ 585 /* This behaviour might be regarded as peculiar, it appears 586 that the 80486 rounds to the dest precision, then 587 converts to decide underflow. */ 588 if (!((tmp.sigl == 0x00800000) && 589 ((st0_ptr->sigh & 0x000000ff) 590 || st0_ptr->sigl))) 591 #endif /* PECULIAR_486 */ 592 { 593 EXCEPTION(EX_Underflow); 594 /* This is a special case: see sec 16.2.5.1 of 595 the 80486 book */ 596 if (!(control_word & CW_Underflow)) 597 return 0; 598 } 599 EXCEPTION(precision_loss); 600 if (!(control_word & CW_Precision)) 601 return 0; 602 } 603 templ = tmp.sigl; 604 } else { 605 if (tmp.sigl | (tmp.sigh & 0x000000ff)) { 606 unsigned long sigh = tmp.sigh; 607 unsigned long sigl = tmp.sigl; 608 609 precision_loss = 1; 610 switch (control_word & CW_RC) { 611 case RC_RND: 612 increment = ((sigh & 0xff) > 0x80) /* more than half */ 613 ||(((sigh & 0xff) == 0x80) && sigl) /* more than half */ 614 ||((sigh & 0x180) == 0x180); /* round to even */ 615 break; 616 case RC_DOWN: /* towards -infinity */ 617 increment = signpositive(&tmp) 618 ? 0 : (sigl | (sigh & 0xff)); 619 break; 620 case RC_UP: /* towards +infinity */ 621 increment = signpositive(&tmp) 622 ? (sigl | (sigh & 0xff)) : 0; 623 break; 624 case RC_CHOP: 625 increment = 0; 626 break; 627 } 628 629 /* Truncate part of the mantissa */ 630 tmp.sigl = 0; 631 632 if (increment) { 633 if (sigh >= 0xffffff00) { 634 /* The sigh part overflows */ 635 tmp.sigh = 0x80000000; 636 exp++; 637 if (exp >= EXP_OVER) 638 goto overflow; 639 } else { 640 tmp.sigh &= 0xffffff00; 641 tmp.sigh += 0x100; 642 } 643 } else { 644 tmp.sigh &= 0xffffff00; /* Finish the truncation */ 645 } 646 } else 647 precision_loss = 0; 648 649 templ = (tmp.sigh >> 8) & 0x007fffff; 650 651 if (exp > SINGLE_Emax) { 652 overflow: 653 EXCEPTION(EX_Overflow); 654 if (!(control_word & CW_Overflow)) 655 return 0; 656 set_precision_flag_up(); 657 if (!(control_word & CW_Precision)) 658 return 0; 659 660 /* This is a special case: see sec 16.2.5.1 of the 80486 book. */ 661 /* Masked response is overflow to infinity. */ 662 templ = 0x7f800000; 663 } else { 664 if (precision_loss) { 665 if (increment) 666 set_precision_flag_up(); 667 else 668 set_precision_flag_down(); 669 } 670 /* Add the exponent */ 671 templ |= ((exp + SINGLE_Ebias) & 0xff) << 23; 672 } 673 } 674 } else if (st0_tag == TAG_Zero) { 675 templ = 0; 676 } else if (st0_tag == TAG_Special) { 677 st0_tag = FPU_Special(st0_ptr); 678 if (st0_tag == TW_Denormal) { 679 reg_copy(st0_ptr, &tmp); 680 681 /* A denormal will always underflow. */ 682 #ifndef PECULIAR_486 683 /* An 80486 is supposed to be able to generate 684 a denormal exception here, but... */ 685 /* Underflow has priority. */ 686 if (control_word & CW_Underflow) 687 denormal_operand(); 688 #endif /* PECULIAR_486 */ 689 goto denormal_arg; 690 } else if (st0_tag == TW_Infinity) { 691 templ = 0x7f800000; 692 } else if (st0_tag == TW_NaN) { 693 /* Is it really a NaN ? */ 694 if ((exponent(st0_ptr) == EXP_OVER) 695 && (st0_ptr->sigh & 0x80000000)) { 696 /* See if we can get a valid NaN from the FPU_REG */ 697 templ = st0_ptr->sigh >> 8; 698 if (!(st0_ptr->sigh & 0x40000000)) { 699 /* It is a signalling NaN */ 700 EXCEPTION(EX_Invalid); 701 if (!(control_word & CW_Invalid)) 702 return 0; 703 templ |= (0x40000000 >> 8); 704 } 705 templ |= 0x7f800000; 706 } else { 707 /* It is an unsupported data type */ 708 EXCEPTION(EX_Invalid); 709 if (!(control_word & CW_Invalid)) 710 return 0; 711 templ = 0xffc00000; 712 } 713 } 714 #ifdef PARANOID 715 else { 716 EXCEPTION(EX_INTERNAL | 0x164); 717 return 0; 718 } 719 #endif 720 } else if (st0_tag == TAG_Empty) { 721 /* Empty register (stack underflow) */ 722 EXCEPTION(EX_StackUnder); 723 if (control_word & EX_Invalid) { 724 /* The masked response */ 725 /* Put out the QNaN indefinite */ 726 RE_ENTRANT_CHECK_OFF; 727 FPU_access_ok(single, 4); 728 FPU_put_user(0xffc00000, 729 (unsigned long __user *)single); 730 RE_ENTRANT_CHECK_ON; 731 return 1; 732 } else 733 return 0; 734 } 735 #ifdef PARANOID 736 else { 737 EXCEPTION(EX_INTERNAL | 0x163); 738 return 0; 739 } 740 #endif 741 if (getsign(st0_ptr)) 742 templ |= 0x80000000; 743 744 RE_ENTRANT_CHECK_OFF; 745 FPU_access_ok(single, 4); 746 FPU_put_user(templ, (unsigned long __user *)single); 747 RE_ENTRANT_CHECK_ON; 748 749 return 1; 750 } 751 752 /* Put a long long into user memory */ 753 int FPU_store_int64(FPU_REG *st0_ptr, u_char st0_tag, long long __user *d) 754 { 755 FPU_REG t; 756 long long tll; 757 int precision_loss; 758 759 if (st0_tag == TAG_Empty) { 760 /* Empty register (stack underflow) */ 761 EXCEPTION(EX_StackUnder); 762 goto invalid_operand; 763 } else if (st0_tag == TAG_Special) { 764 st0_tag = FPU_Special(st0_ptr); 765 if ((st0_tag == TW_Infinity) || (st0_tag == TW_NaN)) { 766 EXCEPTION(EX_Invalid); 767 goto invalid_operand; 768 } 769 } 770 771 reg_copy(st0_ptr, &t); 772 precision_loss = FPU_round_to_int(&t, st0_tag); 773 ((long *)&tll)[0] = t.sigl; 774 ((long *)&tll)[1] = t.sigh; 775 if ((precision_loss == 1) || 776 ((t.sigh & 0x80000000) && 777 !((t.sigh == 0x80000000) && (t.sigl == 0) && signnegative(&t)))) { 778 EXCEPTION(EX_Invalid); 779 /* This is a special case: see sec 16.2.5.1 of the 80486 book */ 780 invalid_operand: 781 if (control_word & EX_Invalid) { 782 /* Produce something like QNaN "indefinite" */ 783 tll = 0x8000000000000000LL; 784 } else 785 return 0; 786 } else { 787 if (precision_loss) 788 set_precision_flag(precision_loss); 789 if (signnegative(&t)) 790 tll = -tll; 791 } 792 793 RE_ENTRANT_CHECK_OFF; 794 FPU_access_ok(d, 8); 795 if (copy_to_user(d, &tll, 8)) 796 FPU_abort; 797 RE_ENTRANT_CHECK_ON; 798 799 return 1; 800 } 801 802 /* Put a long into user memory */ 803 int FPU_store_int32(FPU_REG *st0_ptr, u_char st0_tag, long __user *d) 804 { 805 FPU_REG t; 806 int precision_loss; 807 808 if (st0_tag == TAG_Empty) { 809 /* Empty register (stack underflow) */ 810 EXCEPTION(EX_StackUnder); 811 goto invalid_operand; 812 } else if (st0_tag == TAG_Special) { 813 st0_tag = FPU_Special(st0_ptr); 814 if ((st0_tag == TW_Infinity) || (st0_tag == TW_NaN)) { 815 EXCEPTION(EX_Invalid); 816 goto invalid_operand; 817 } 818 } 819 820 reg_copy(st0_ptr, &t); 821 precision_loss = FPU_round_to_int(&t, st0_tag); 822 if (t.sigh || 823 ((t.sigl & 0x80000000) && 824 !((t.sigl == 0x80000000) && signnegative(&t)))) { 825 EXCEPTION(EX_Invalid); 826 /* This is a special case: see sec 16.2.5.1 of the 80486 book */ 827 invalid_operand: 828 if (control_word & EX_Invalid) { 829 /* Produce something like QNaN "indefinite" */ 830 t.sigl = 0x80000000; 831 } else 832 return 0; 833 } else { 834 if (precision_loss) 835 set_precision_flag(precision_loss); 836 if (signnegative(&t)) 837 t.sigl = -(long)t.sigl; 838 } 839 840 RE_ENTRANT_CHECK_OFF; 841 FPU_access_ok(d, 4); 842 FPU_put_user(t.sigl, (unsigned long __user *)d); 843 RE_ENTRANT_CHECK_ON; 844 845 return 1; 846 } 847 848 /* Put a short into user memory */ 849 int FPU_store_int16(FPU_REG *st0_ptr, u_char st0_tag, short __user *d) 850 { 851 FPU_REG t; 852 int precision_loss; 853 854 if (st0_tag == TAG_Empty) { 855 /* Empty register (stack underflow) */ 856 EXCEPTION(EX_StackUnder); 857 goto invalid_operand; 858 } else if (st0_tag == TAG_Special) { 859 st0_tag = FPU_Special(st0_ptr); 860 if ((st0_tag == TW_Infinity) || (st0_tag == TW_NaN)) { 861 EXCEPTION(EX_Invalid); 862 goto invalid_operand; 863 } 864 } 865 866 reg_copy(st0_ptr, &t); 867 precision_loss = FPU_round_to_int(&t, st0_tag); 868 if (t.sigh || 869 ((t.sigl & 0xffff8000) && 870 !((t.sigl == 0x8000) && signnegative(&t)))) { 871 EXCEPTION(EX_Invalid); 872 /* This is a special case: see sec 16.2.5.1 of the 80486 book */ 873 invalid_operand: 874 if (control_word & EX_Invalid) { 875 /* Produce something like QNaN "indefinite" */ 876 t.sigl = 0x8000; 877 } else 878 return 0; 879 } else { 880 if (precision_loss) 881 set_precision_flag(precision_loss); 882 if (signnegative(&t)) 883 t.sigl = -t.sigl; 884 } 885 886 RE_ENTRANT_CHECK_OFF; 887 FPU_access_ok(d, 2); 888 FPU_put_user((short)t.sigl, d); 889 RE_ENTRANT_CHECK_ON; 890 891 return 1; 892 } 893 894 /* Put a packed bcd array into user memory */ 895 int FPU_store_bcd(FPU_REG *st0_ptr, u_char st0_tag, u_char __user *d) 896 { 897 FPU_REG t; 898 unsigned long long ll; 899 u_char b; 900 int i, precision_loss; 901 u_char sign = (getsign(st0_ptr) == SIGN_NEG) ? 0x80 : 0; 902 903 if (st0_tag == TAG_Empty) { 904 /* Empty register (stack underflow) */ 905 EXCEPTION(EX_StackUnder); 906 goto invalid_operand; 907 } else if (st0_tag == TAG_Special) { 908 st0_tag = FPU_Special(st0_ptr); 909 if ((st0_tag == TW_Infinity) || (st0_tag == TW_NaN)) { 910 EXCEPTION(EX_Invalid); 911 goto invalid_operand; 912 } 913 } 914 915 reg_copy(st0_ptr, &t); 916 precision_loss = FPU_round_to_int(&t, st0_tag); 917 ll = significand(&t); 918 919 /* Check for overflow, by comparing with 999999999999999999 decimal. */ 920 if ((t.sigh > 0x0de0b6b3) || 921 ((t.sigh == 0x0de0b6b3) && (t.sigl > 0xa763ffff))) { 922 EXCEPTION(EX_Invalid); 923 /* This is a special case: see sec 16.2.5.1 of the 80486 book */ 924 invalid_operand: 925 if (control_word & CW_Invalid) { 926 /* Produce the QNaN "indefinite" */ 927 RE_ENTRANT_CHECK_OFF; 928 FPU_access_ok(d, 10); 929 for (i = 0; i < 7; i++) 930 FPU_put_user(0, d + i); /* These bytes "undefined" */ 931 FPU_put_user(0xc0, d + 7); /* This byte "undefined" */ 932 FPU_put_user(0xff, d + 8); 933 FPU_put_user(0xff, d + 9); 934 RE_ENTRANT_CHECK_ON; 935 return 1; 936 } else 937 return 0; 938 } else if (precision_loss) { 939 /* Precision loss doesn't stop the data transfer */ 940 set_precision_flag(precision_loss); 941 } 942 943 RE_ENTRANT_CHECK_OFF; 944 FPU_access_ok(d, 10); 945 RE_ENTRANT_CHECK_ON; 946 for (i = 0; i < 9; i++) { 947 b = FPU_div_small(&ll, 10); 948 b |= (FPU_div_small(&ll, 10)) << 4; 949 RE_ENTRANT_CHECK_OFF; 950 FPU_put_user(b, d + i); 951 RE_ENTRANT_CHECK_ON; 952 } 953 RE_ENTRANT_CHECK_OFF; 954 FPU_put_user(sign, d + 9); 955 RE_ENTRANT_CHECK_ON; 956 957 return 1; 958 } 959 960 /*===========================================================================*/ 961 962 /* r gets mangled such that sig is int, sign: 963 it is NOT normalized */ 964 /* The return value (in eax) is zero if the result is exact, 965 if bits are changed due to rounding, truncation, etc, then 966 a non-zero value is returned */ 967 /* Overflow is signaled by a non-zero return value (in eax). 968 In the case of overflow, the returned significand always has the 969 largest possible value */ 970 int FPU_round_to_int(FPU_REG *r, u_char tag) 971 { 972 u_char very_big; 973 unsigned eax; 974 975 if (tag == TAG_Zero) { 976 /* Make sure that zero is returned */ 977 significand(r) = 0; 978 return 0; /* o.k. */ 979 } 980 981 if (exponent(r) > 63) { 982 r->sigl = r->sigh = ~0; /* The largest representable number */ 983 return 1; /* overflow */ 984 } 985 986 eax = FPU_shrxs(&r->sigl, 63 - exponent(r)); 987 very_big = !(~(r->sigh) | ~(r->sigl)); /* test for 0xfff...fff */ 988 #define half_or_more (eax & 0x80000000) 989 #define frac_part (eax) 990 #define more_than_half ((eax & 0x80000001) == 0x80000001) 991 switch (control_word & CW_RC) { 992 case RC_RND: 993 if (more_than_half /* nearest */ 994 || (half_or_more && (r->sigl & 1))) { /* odd -> even */ 995 if (very_big) 996 return 1; /* overflow */ 997 significand(r)++; 998 return PRECISION_LOST_UP; 999 } 1000 break; 1001 case RC_DOWN: 1002 if (frac_part && getsign(r)) { 1003 if (very_big) 1004 return 1; /* overflow */ 1005 significand(r)++; 1006 return PRECISION_LOST_UP; 1007 } 1008 break; 1009 case RC_UP: 1010 if (frac_part && !getsign(r)) { 1011 if (very_big) 1012 return 1; /* overflow */ 1013 significand(r)++; 1014 return PRECISION_LOST_UP; 1015 } 1016 break; 1017 case RC_CHOP: 1018 break; 1019 } 1020 1021 return eax ? PRECISION_LOST_DOWN : 0; 1022 1023 } 1024 1025 /*===========================================================================*/ 1026 1027 u_char __user *fldenv(fpu_addr_modes addr_modes, u_char __user *s) 1028 { 1029 unsigned short tag_word = 0; 1030 u_char tag; 1031 int i; 1032 1033 if ((addr_modes.default_mode == VM86) || 1034 ((addr_modes.default_mode == PM16) 1035 ^ (addr_modes.override.operand_size == OP_SIZE_PREFIX))) { 1036 RE_ENTRANT_CHECK_OFF; 1037 FPU_access_ok(s, 0x0e); 1038 FPU_get_user(control_word, (unsigned short __user *)s); 1039 FPU_get_user(partial_status, (unsigned short __user *)(s + 2)); 1040 FPU_get_user(tag_word, (unsigned short __user *)(s + 4)); 1041 FPU_get_user(instruction_address.offset, 1042 (unsigned short __user *)(s + 6)); 1043 FPU_get_user(instruction_address.selector, 1044 (unsigned short __user *)(s + 8)); 1045 FPU_get_user(operand_address.offset, 1046 (unsigned short __user *)(s + 0x0a)); 1047 FPU_get_user(operand_address.selector, 1048 (unsigned short __user *)(s + 0x0c)); 1049 RE_ENTRANT_CHECK_ON; 1050 s += 0x0e; 1051 if (addr_modes.default_mode == VM86) { 1052 instruction_address.offset 1053 += (instruction_address.selector & 0xf000) << 4; 1054 operand_address.offset += 1055 (operand_address.selector & 0xf000) << 4; 1056 } 1057 } else { 1058 RE_ENTRANT_CHECK_OFF; 1059 FPU_access_ok(s, 0x1c); 1060 FPU_get_user(control_word, (unsigned short __user *)s); 1061 FPU_get_user(partial_status, (unsigned short __user *)(s + 4)); 1062 FPU_get_user(tag_word, (unsigned short __user *)(s + 8)); 1063 FPU_get_user(instruction_address.offset, 1064 (unsigned long __user *)(s + 0x0c)); 1065 FPU_get_user(instruction_address.selector, 1066 (unsigned short __user *)(s + 0x10)); 1067 FPU_get_user(instruction_address.opcode, 1068 (unsigned short __user *)(s + 0x12)); 1069 FPU_get_user(operand_address.offset, 1070 (unsigned long __user *)(s + 0x14)); 1071 FPU_get_user(operand_address.selector, 1072 (unsigned long __user *)(s + 0x18)); 1073 RE_ENTRANT_CHECK_ON; 1074 s += 0x1c; 1075 } 1076 1077 #ifdef PECULIAR_486 1078 control_word &= ~0xe080; 1079 #endif /* PECULIAR_486 */ 1080 1081 top = (partial_status >> SW_Top_Shift) & 7; 1082 1083 if (partial_status & ~control_word & CW_Exceptions) 1084 partial_status |= (SW_Summary | SW_Backward); 1085 else 1086 partial_status &= ~(SW_Summary | SW_Backward); 1087 1088 for (i = 0; i < 8; i++) { 1089 tag = tag_word & 3; 1090 tag_word >>= 2; 1091 1092 if (tag == TAG_Empty) 1093 /* New tag is empty. Accept it */ 1094 FPU_settag(i, TAG_Empty); 1095 else if (FPU_gettag(i) == TAG_Empty) { 1096 /* Old tag is empty and new tag is not empty. New tag is determined 1097 by old reg contents */ 1098 if (exponent(&fpu_register(i)) == -EXTENDED_Ebias) { 1099 if (! 1100 (fpu_register(i).sigl | fpu_register(i). 1101 sigh)) 1102 FPU_settag(i, TAG_Zero); 1103 else 1104 FPU_settag(i, TAG_Special); 1105 } else if (exponent(&fpu_register(i)) == 1106 0x7fff - EXTENDED_Ebias) { 1107 FPU_settag(i, TAG_Special); 1108 } else if (fpu_register(i).sigh & 0x80000000) 1109 FPU_settag(i, TAG_Valid); 1110 else 1111 FPU_settag(i, TAG_Special); /* An Un-normal */ 1112 } 1113 /* Else old tag is not empty and new tag is not empty. Old tag 1114 remains correct */ 1115 } 1116 1117 return s; 1118 } 1119 1120 void FPU_frstor(fpu_addr_modes addr_modes, u_char __user *data_address) 1121 { 1122 int i, regnr; 1123 u_char __user *s = fldenv(addr_modes, data_address); 1124 int offset = (top & 7) * 10, other = 80 - offset; 1125 1126 /* Copy all registers in stack order. */ 1127 RE_ENTRANT_CHECK_OFF; 1128 FPU_access_ok(s, 80); 1129 FPU_copy_from_user(register_base + offset, s, other); 1130 if (offset) 1131 FPU_copy_from_user(register_base, s + other, offset); 1132 RE_ENTRANT_CHECK_ON; 1133 1134 for (i = 0; i < 8; i++) { 1135 regnr = (i + top) & 7; 1136 if (FPU_gettag(regnr) != TAG_Empty) 1137 /* The loaded data over-rides all other cases. */ 1138 FPU_settag(regnr, FPU_tagof(&st(i))); 1139 } 1140 1141 } 1142 1143 u_char __user *fstenv(fpu_addr_modes addr_modes, u_char __user *d) 1144 { 1145 if ((addr_modes.default_mode == VM86) || 1146 ((addr_modes.default_mode == PM16) 1147 ^ (addr_modes.override.operand_size == OP_SIZE_PREFIX))) { 1148 RE_ENTRANT_CHECK_OFF; 1149 FPU_access_ok(d, 14); 1150 #ifdef PECULIAR_486 1151 FPU_put_user(control_word & ~0xe080, (unsigned long __user *)d); 1152 #else 1153 FPU_put_user(control_word, (unsigned short __user *)d); 1154 #endif /* PECULIAR_486 */ 1155 FPU_put_user(status_word(), (unsigned short __user *)(d + 2)); 1156 FPU_put_user(fpu_tag_word, (unsigned short __user *)(d + 4)); 1157 FPU_put_user(instruction_address.offset, 1158 (unsigned short __user *)(d + 6)); 1159 FPU_put_user(operand_address.offset, 1160 (unsigned short __user *)(d + 0x0a)); 1161 if (addr_modes.default_mode == VM86) { 1162 FPU_put_user((instruction_address. 1163 offset & 0xf0000) >> 4, 1164 (unsigned short __user *)(d + 8)); 1165 FPU_put_user((operand_address.offset & 0xf0000) >> 4, 1166 (unsigned short __user *)(d + 0x0c)); 1167 } else { 1168 FPU_put_user(instruction_address.selector, 1169 (unsigned short __user *)(d + 8)); 1170 FPU_put_user(operand_address.selector, 1171 (unsigned short __user *)(d + 0x0c)); 1172 } 1173 RE_ENTRANT_CHECK_ON; 1174 d += 0x0e; 1175 } else { 1176 RE_ENTRANT_CHECK_OFF; 1177 FPU_access_ok(d, 7 * 4); 1178 #ifdef PECULIAR_486 1179 control_word &= ~0xe080; 1180 /* An 80486 sets nearly all of the reserved bits to 1. */ 1181 control_word |= 0xffff0040; 1182 partial_status = status_word() | 0xffff0000; 1183 fpu_tag_word |= 0xffff0000; 1184 I387->soft.fcs &= ~0xf8000000; 1185 I387->soft.fos |= 0xffff0000; 1186 #endif /* PECULIAR_486 */ 1187 if (__copy_to_user(d, &control_word, 7 * 4)) 1188 FPU_abort; 1189 RE_ENTRANT_CHECK_ON; 1190 d += 0x1c; 1191 } 1192 1193 control_word |= CW_Exceptions; 1194 partial_status &= ~(SW_Summary | SW_Backward); 1195 1196 return d; 1197 } 1198 1199 void fsave(fpu_addr_modes addr_modes, u_char __user *data_address) 1200 { 1201 u_char __user *d; 1202 int offset = (top & 7) * 10, other = 80 - offset; 1203 1204 d = fstenv(addr_modes, data_address); 1205 1206 RE_ENTRANT_CHECK_OFF; 1207 FPU_access_ok(d, 80); 1208 1209 /* Copy all registers in stack order. */ 1210 if (__copy_to_user(d, register_base + offset, other)) 1211 FPU_abort; 1212 if (offset) 1213 if (__copy_to_user(d + other, register_base, offset)) 1214 FPU_abort; 1215 RE_ENTRANT_CHECK_ON; 1216 1217 finit(); 1218 } 1219 1220 /*===========================================================================*/ 1221