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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 | /*---------------------------------------------------------------------------+ | errors.c | | | | The error handling functions for wm-FPU-emu | | | | Copyright (C) 1992,1993,1994,1996 | | W. Metzenthen, 22 Parker St, Ormond, Vic 3163, Australia | | E-mail billm@jacobi.maths.monash.edu.au | | | | | +---------------------------------------------------------------------------*/ /*---------------------------------------------------------------------------+ | Note: | | The file contains code which accesses user memory. | | Emulator static data may change when user memory is accessed, due to | | other processes using the emulator while swapping is in progress. | +---------------------------------------------------------------------------*/ #include <linux/signal.h> #include <asm/uaccess.h> #include "fpu_emu.h" #include "fpu_system.h" #include "exception.h" #include "status_w.h" #include "control_w.h" #include "reg_constant.h" #include "version.h" /* */ #undef PRINT_MESSAGES /* */ void Un_impl(void) { u_char byte1, FPU_modrm; unsigned long address = FPU_ORIG_EIP; RE_ENTRANT_CHECK_OFF; /* No need to verify_area(), we have previously fetched these bytes. */ printk("Unimplemented FPU Opcode at eip=%p : ", (void *) address); if ( FPU_CS == __USER_CS ) { while ( 1 ) { FPU_get_user(byte1, (u_char *) address); if ( (byte1 & 0xf8) == 0xd8 ) break; printk("[%02x]", byte1); address++; } printk("%02x ", byte1); FPU_get_user(FPU_modrm, 1 + (u_char *) address); if (FPU_modrm >= 0300) printk("%02x (%02x+%d)\n", FPU_modrm, FPU_modrm & 0xf8, FPU_modrm & 7); else printk("/%d\n", (FPU_modrm >> 3) & 7); } else { printk("cs selector = %04x\n", FPU_CS); } RE_ENTRANT_CHECK_ON; EXCEPTION(EX_Invalid); } /* Called for opcodes which are illegal and which are known to result in a SIGILL with a real 80486. */ void FPU_illegal(void) { math_abort(FPU_info,SIGILL); } void FPU_printall(void) { int i; static const char *tag_desc[] = { "Valid", "Zero", "ERROR", "Empty", "DeNorm", "Inf", "NaN" }; u_char byte1, FPU_modrm; unsigned long address = FPU_ORIG_EIP; RE_ENTRANT_CHECK_OFF; /* No need to verify_area(), we have previously fetched these bytes. */ printk("At %p:", (void *) address); if ( FPU_CS == __USER_CS ) { #define MAX_PRINTED_BYTES 20 for ( i = 0; i < MAX_PRINTED_BYTES; i++ ) { FPU_get_user(byte1, (u_char *) address); if ( (byte1 & 0xf8) == 0xd8 ) { printk(" %02x", byte1); break; } printk(" [%02x]", byte1); address++; } if ( i == MAX_PRINTED_BYTES ) printk(" [more..]\n"); else { FPU_get_user(FPU_modrm, 1 + (u_char *) address); if (FPU_modrm >= 0300) printk(" %02x (%02x+%d)\n", FPU_modrm, FPU_modrm & 0xf8, FPU_modrm & 7); else printk(" /%d, mod=%d rm=%d\n", (FPU_modrm >> 3) & 7, (FPU_modrm >> 6) & 3, FPU_modrm & 7); } } else { printk("%04x\n", FPU_CS); } partial_status = status_word(); #ifdef DEBUGGING if ( partial_status & SW_Backward ) printk("SW: backward compatibility\n"); if ( partial_status & SW_C3 ) printk("SW: condition bit 3\n"); if ( partial_status & SW_C2 ) printk("SW: condition bit 2\n"); if ( partial_status & SW_C1 ) printk("SW: condition bit 1\n"); if ( partial_status & SW_C0 ) printk("SW: condition bit 0\n"); if ( partial_status & SW_Summary ) printk("SW: exception summary\n"); if ( partial_status & SW_Stack_Fault ) printk("SW: stack fault\n"); if ( partial_status & SW_Precision ) printk("SW: loss of precision\n"); if ( partial_status & SW_Underflow ) printk("SW: underflow\n"); if ( partial_status & SW_Overflow ) printk("SW: overflow\n"); if ( partial_status & SW_Zero_Div ) printk("SW: divide by zero\n"); if ( partial_status & SW_Denorm_Op ) printk("SW: denormalized operand\n"); if ( partial_status & SW_Invalid ) printk("SW: invalid operation\n"); #endif /* DEBUGGING */ printk(" SW: b=%d st=%ld es=%d sf=%d cc=%d%d%d%d ef=%d%d%d%d%d%d\n", partial_status & 0x8000 ? 1 : 0, /* busy */ (partial_status & 0x3800) >> 11, /* stack top pointer */ partial_status & 0x80 ? 1 : 0, /* Error summary status */ partial_status & 0x40 ? 1 : 0, /* Stack flag */ partial_status & SW_C3?1:0, partial_status & SW_C2?1:0, /* cc */ partial_status & SW_C1?1:0, partial_status & SW_C0?1:0, /* cc */ partial_status & SW_Precision?1:0, partial_status & SW_Underflow?1:0, partial_status & SW_Overflow?1:0, partial_status & SW_Zero_Div?1:0, partial_status & SW_Denorm_Op?1:0, partial_status & SW_Invalid?1:0); printk(" CW: ic=%d rc=%ld%ld pc=%ld%ld iem=%d ef=%d%d%d%d%d%d\n", control_word & 0x1000 ? 1 : 0, (control_word & 0x800) >> 11, (control_word & 0x400) >> 10, (control_word & 0x200) >> 9, (control_word & 0x100) >> 8, control_word & 0x80 ? 1 : 0, control_word & SW_Precision?1:0, control_word & SW_Underflow?1:0, control_word & SW_Overflow?1:0, control_word & SW_Zero_Div?1:0, control_word & SW_Denorm_Op?1:0, control_word & SW_Invalid?1:0); for ( i = 0; i < 8; i++ ) { FPU_REG *r = &st(i); u_char tagi = FPU_gettagi(i); switch (tagi) { case TAG_Empty: continue; break; case TAG_Zero: case TAG_Special: tagi = FPU_Special(r); case TAG_Valid: printk("st(%d) %c .%04lx %04lx %04lx %04lx e%+-6d ", i, getsign(r) ? '-' : '+', (long)(r->sigh >> 16), (long)(r->sigh & 0xFFFF), (long)(r->sigl >> 16), (long)(r->sigl & 0xFFFF), exponent(r) - EXP_BIAS + 1); break; default: printk("Whoops! Error in errors.c: tag%d is %d ", i, tagi); continue; break; } printk("%s\n", tag_desc[(int) (unsigned) tagi]); } RE_ENTRANT_CHECK_ON; } static struct { int type; const char *name; } exception_names[] = { { EX_StackOver, "stack overflow" }, { EX_StackUnder, "stack underflow" }, { EX_Precision, "loss of precision" }, { EX_Underflow, "underflow" }, { EX_Overflow, "overflow" }, { EX_ZeroDiv, "divide by zero" }, { EX_Denormal, "denormalized operand" }, { EX_Invalid, "invalid operation" }, { EX_INTERNAL, "INTERNAL BUG in "FPU_VERSION }, { 0, NULL } }; /* EX_INTERNAL is always given with a code which indicates where the error was detected. Internal error types: 0x14 in fpu_etc.c 0x1nn in a *.c file: 0x101 in reg_add_sub.c 0x102 in reg_mul.c 0x104 in poly_atan.c 0x105 in reg_mul.c 0x107 in fpu_trig.c 0x108 in reg_compare.c 0x109 in reg_compare.c 0x110 in reg_add_sub.c 0x111 in fpe_entry.c 0x112 in fpu_trig.c 0x113 in errors.c 0x115 in fpu_trig.c 0x116 in fpu_trig.c 0x117 in fpu_trig.c 0x118 in fpu_trig.c 0x119 in fpu_trig.c 0x120 in poly_atan.c 0x121 in reg_compare.c 0x122 in reg_compare.c 0x123 in reg_compare.c 0x125 in fpu_trig.c 0x126 in fpu_entry.c 0x127 in poly_2xm1.c 0x128 in fpu_entry.c 0x129 in fpu_entry.c 0x130 in get_address.c 0x131 in get_address.c 0x132 in get_address.c 0x133 in get_address.c 0x140 in load_store.c 0x141 in load_store.c 0x150 in poly_sin.c 0x151 in poly_sin.c 0x160 in reg_ld_str.c 0x161 in reg_ld_str.c 0x162 in reg_ld_str.c 0x163 in reg_ld_str.c 0x164 in reg_ld_str.c 0x170 in fpu_tags.c 0x171 in fpu_tags.c 0x172 in fpu_tags.c 0x180 in reg_convert.c 0x2nn in an *.S file: 0x201 in reg_u_add.S 0x202 in reg_u_div.S 0x203 in reg_u_div.S 0x204 in reg_u_div.S 0x205 in reg_u_mul.S 0x206 in reg_u_sub.S 0x207 in wm_sqrt.S 0x208 in reg_div.S 0x209 in reg_u_sub.S 0x210 in reg_u_sub.S 0x211 in reg_u_sub.S 0x212 in reg_u_sub.S 0x213 in wm_sqrt.S 0x214 in wm_sqrt.S 0x215 in wm_sqrt.S 0x220 in reg_norm.S 0x221 in reg_norm.S 0x230 in reg_round.S 0x231 in reg_round.S 0x232 in reg_round.S 0x233 in reg_round.S 0x234 in reg_round.S 0x235 in reg_round.S 0x236 in reg_round.S 0x240 in div_Xsig.S 0x241 in div_Xsig.S 0x242 in div_Xsig.S */ void FPU_exception(int n) { int i, int_type; int_type = 0; /* Needed only to stop compiler warnings */ if ( n & EX_INTERNAL ) { int_type = n - EX_INTERNAL; n = EX_INTERNAL; /* Set lots of exception bits! */ partial_status |= (SW_Exc_Mask | SW_Summary | SW_Backward); } else { /* Extract only the bits which we use to set the status word */ n &= (SW_Exc_Mask); /* Set the corresponding exception bit */ partial_status |= n; /* Set summary bits iff exception isn't masked */ if ( partial_status & ~control_word & CW_Exceptions ) partial_status |= (SW_Summary | SW_Backward); if ( n & (SW_Stack_Fault | EX_Precision) ) { if ( !(n & SW_C1) ) /* This bit distinguishes over- from underflow for a stack fault, and roundup from round-down for precision loss. */ partial_status &= ~SW_C1; } } RE_ENTRANT_CHECK_OFF; if ( (~control_word & n & CW_Exceptions) || (n == EX_INTERNAL) ) { #ifdef PRINT_MESSAGES /* My message from the sponsor */ printk(FPU_VERSION" "__DATE__" (C) W. Metzenthen.\n"); #endif /* PRINT_MESSAGES */ /* Get a name string for error reporting */ for (i=0; exception_names[i].type; i++) if ( (exception_names[i].type & n) == exception_names[i].type ) break; if (exception_names[i].type) { #ifdef PRINT_MESSAGES printk("FP Exception: %s!\n", exception_names[i].name); #endif /* PRINT_MESSAGES */ } else printk("FPU emulator: Unknown Exception: 0x%04x!\n", n); if ( n == EX_INTERNAL ) { printk("FPU emulator: Internal error type 0x%04x\n", int_type); FPU_printall(); } #ifdef PRINT_MESSAGES else FPU_printall(); #endif /* PRINT_MESSAGES */ /* * The 80486 generates an interrupt on the next non-control FPU * instruction. So we need some means of flagging it. * We use the ES (Error Summary) bit for this. */ } RE_ENTRANT_CHECK_ON; #ifdef __DEBUG__ math_abort(FPU_info,SIGFPE); #endif /* __DEBUG__ */ } /* Real operation attempted on a NaN. */ /* Returns < 0 if the exception is unmasked */ int real_1op_NaN(FPU_REG *a) { int signalling, isNaN; isNaN = (exponent(a) == EXP_OVER) && (a->sigh & 0x80000000); /* The default result for the case of two "equal" NaNs (signs may differ) is chosen to reproduce 80486 behaviour */ signalling = isNaN && !(a->sigh & 0x40000000); if ( !signalling ) { if ( !isNaN ) /* pseudo-NaN, or other unsupported? */ { if ( control_word & CW_Invalid ) { /* Masked response */ reg_copy(&CONST_QNaN, a); } EXCEPTION(EX_Invalid); return (!(control_word & CW_Invalid) ? FPU_Exception : 0) | TAG_Special; } return TAG_Special; } if ( control_word & CW_Invalid ) { /* The masked response */ if ( !(a->sigh & 0x80000000) ) /* pseudo-NaN ? */ { reg_copy(&CONST_QNaN, a); } /* ensure a Quiet NaN */ a->sigh |= 0x40000000; } EXCEPTION(EX_Invalid); return (!(control_word & CW_Invalid) ? FPU_Exception : 0) | TAG_Special; } /* Real operation attempted on two operands, one a NaN. */ /* Returns < 0 if the exception is unmasked */ int real_2op_NaN(FPU_REG const *b, u_char tagb, int deststnr, FPU_REG const *defaultNaN) { FPU_REG *dest = &st(deststnr); FPU_REG const *a = dest; u_char taga = FPU_gettagi(deststnr); FPU_REG const *x; int signalling, unsupported; if ( taga == TAG_Special ) taga = FPU_Special(a); if ( tagb == TAG_Special ) tagb = FPU_Special(b); /* TW_NaN is also used for unsupported data types. */ unsupported = ((taga == TW_NaN) && !((exponent(a) == EXP_OVER) && (a->sigh & 0x80000000))) || ((tagb == TW_NaN) && !((exponent(b) == EXP_OVER) && (b->sigh & 0x80000000))); if ( unsupported ) { if ( control_word & CW_Invalid ) { /* Masked response */ FPU_copy_to_regi(&CONST_QNaN, TAG_Special, deststnr); } EXCEPTION(EX_Invalid); return (!(control_word & CW_Invalid) ? FPU_Exception : 0) | TAG_Special; } if (taga == TW_NaN) { x = a; if (tagb == TW_NaN) { signalling = !(a->sigh & b->sigh & 0x40000000); if ( significand(b) > significand(a) ) x = b; else if ( significand(b) == significand(a) ) { /* The default result for the case of two "equal" NaNs (signs may differ) is chosen to reproduce 80486 behaviour */ x = defaultNaN; } } else { /* return the quiet version of the NaN in a */ signalling = !(a->sigh & 0x40000000); } } else #ifdef PARANOID if (tagb == TW_NaN) #endif /* PARANOID */ { signalling = !(b->sigh & 0x40000000); x = b; } #ifdef PARANOID else { signalling = 0; EXCEPTION(EX_INTERNAL|0x113); x = &CONST_QNaN; } #endif /* PARANOID */ if ( (!signalling) || (control_word & CW_Invalid) ) { if ( ! x ) x = b; if ( !(x->sigh & 0x80000000) ) /* pseudo-NaN ? */ x = &CONST_QNaN; FPU_copy_to_regi(x, TAG_Special, deststnr); if ( !signalling ) return TAG_Special; /* ensure a Quiet NaN */ dest->sigh |= 0x40000000; } EXCEPTION(EX_Invalid); return (!(control_word & CW_Invalid) ? FPU_Exception : 0) | TAG_Special; } /* Invalid arith operation on Valid registers */ /* Returns < 0 if the exception is unmasked */ asmlinkage int arith_invalid(int deststnr) { EXCEPTION(EX_Invalid); if ( control_word & CW_Invalid ) { /* The masked response */ FPU_copy_to_regi(&CONST_QNaN, TAG_Special, deststnr); } return (!(control_word & CW_Invalid) ? FPU_Exception : 0) | TAG_Valid; } /* Divide a finite number by zero */ asmlinkage int FPU_divide_by_zero(int deststnr, u_char sign) { FPU_REG *dest = &st(deststnr); int tag = TAG_Valid; if ( control_word & CW_ZeroDiv ) { /* The masked response */ FPU_copy_to_regi(&CONST_INF, TAG_Special, deststnr); setsign(dest, sign); tag = TAG_Special; } EXCEPTION(EX_ZeroDiv); return (!(control_word & CW_ZeroDiv) ? FPU_Exception : 0) | tag; } /* This may be called often, so keep it lean */ int set_precision_flag(int flags) { if ( control_word & CW_Precision ) { partial_status &= ~(SW_C1 & flags); partial_status |= flags; /* The masked response */ return 0; } else { EXCEPTION(flags); return 1; } } /* This may be called often, so keep it lean */ asmlinkage void set_precision_flag_up(void) { if ( control_word & CW_Precision ) partial_status |= (SW_Precision | SW_C1); /* The masked response */ else EXCEPTION(EX_Precision | SW_C1); } /* This may be called often, so keep it lean */ asmlinkage void set_precision_flag_down(void) { if ( control_word & CW_Precision ) { /* The masked response */ partial_status &= ~SW_C1; partial_status |= SW_Precision; } else EXCEPTION(EX_Precision); } asmlinkage int denormal_operand(void) { if ( control_word & CW_Denormal ) { /* The masked response */ partial_status |= SW_Denorm_Op; return TAG_Special; } else { EXCEPTION(EX_Denormal); return TAG_Special | FPU_Exception; } } asmlinkage int arith_overflow(FPU_REG *dest) { int tag = TAG_Valid; if ( control_word & CW_Overflow ) { /* The masked response */ /* ###### The response here depends upon the rounding mode */ reg_copy(&CONST_INF, dest); tag = TAG_Special; } else { /* Subtract the magic number from the exponent */ addexponent(dest, (-3 * (1 << 13))); } EXCEPTION(EX_Overflow); if ( control_word & CW_Overflow ) { /* The overflow exception is masked. */ /* By definition, precision is lost. The roundup bit (C1) is also set because we have "rounded" upwards to Infinity. */ EXCEPTION(EX_Precision | SW_C1); return tag; } return tag; } asmlinkage int arith_underflow(FPU_REG *dest) { int tag = TAG_Valid; if ( control_word & CW_Underflow ) { /* The masked response */ if ( exponent16(dest) <= EXP_UNDER - 63 ) { reg_copy(&CONST_Z, dest); partial_status &= ~SW_C1; /* Round down. */ tag = TAG_Zero; } else { stdexp(dest); } } else { /* Add the magic number to the exponent. */ addexponent(dest, (3 * (1 << 13)) + EXTENDED_Ebias); } EXCEPTION(EX_Underflow); if ( control_word & CW_Underflow ) { /* The underflow exception is masked. */ EXCEPTION(EX_Precision); return tag; } return tag; } void FPU_stack_overflow(void) { if ( control_word & CW_Invalid ) { /* The masked response */ top--; FPU_copy_to_reg0(&CONST_QNaN, TAG_Special); } EXCEPTION(EX_StackOver); return; } void FPU_stack_underflow(void) { if ( control_word & CW_Invalid ) { /* The masked response */ FPU_copy_to_reg0(&CONST_QNaN, TAG_Special); } EXCEPTION(EX_StackUnder); return; } void FPU_stack_underflow_i(int i) { if ( control_word & CW_Invalid ) { /* The masked response */ FPU_copy_to_regi(&CONST_QNaN, TAG_Special, i); } EXCEPTION(EX_StackUnder); return; } void FPU_stack_underflow_pop(int i) { if ( control_word & CW_Invalid ) { /* The masked response */ FPU_copy_to_regi(&CONST_QNaN, TAG_Special, i); FPU_pop(); } EXCEPTION(EX_StackUnder); return; } |