target/m68k/fpu_helper.c

   1 /*
   2  *  m68k FPU helpers
   3  *
   4  *  Copyright (c) 2006-2007 CodeSourcery
   5  *  Written by Paul Brook
   6  *
   7  * This library is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2 of the License, or (at your option) any later version.
  11  *
  12  * This library is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
  19  */
  20
  21 #include "qemu/osdep.h"
  22 #include "cpu.h"
  23 #include "exec/helper-proto.h"
  24 #include "exec/exec-all.h"
  25 #include "exec/cpu_ldst.h"
  26
  27 /* Undefined offsets may be different on various FPU.
  28  * On 68040 they return 0.0 (floatx80_zero)
  29  */
  30
  31 static const floatx80 fpu_rom[128] = {
  32     [0x00] = make_floatx80_init(0x4000, 0xc90fdaa22168c235ULL),  /* Pi       */
  33     [0x0b] = make_floatx80_init(0x3ffd, 0x9a209a84fbcff798ULL),  /* Log10(2) */
  34     [0x0c] = make_floatx80_init(0x4000, 0xadf85458a2bb4a9aULL),  /* e        */
  35     [0x0d] = make_floatx80_init(0x3fff, 0xb8aa3b295c17f0bcULL),  /* Log2(e)  */
  36     [0x0e] = make_floatx80_init(0x3ffd, 0xde5bd8a937287195ULL),  /* Log10(e) */
  37     [0x0f] = make_floatx80_init(0x0000, 0x0000000000000000ULL),  /* Zero     */
  38     [0x30] = make_floatx80_init(0x3ffe, 0xb17217f7d1cf79acULL),  /* ln(2)    */
  39     [0x31] = make_floatx80_init(0x4000, 0x935d8dddaaa8ac17ULL),  /* ln(10)   */
  40     [0x32] = make_floatx80_init(0x3fff, 0x8000000000000000ULL),  /* 10^0     */
  41     [0x33] = make_floatx80_init(0x4002, 0xa000000000000000ULL),  /* 10^1     */
  42     [0x34] = make_floatx80_init(0x4005, 0xc800000000000000ULL),  /* 10^2     */
  43     [0x35] = make_floatx80_init(0x400c, 0x9c40000000000000ULL),  /* 10^4     */
  44     [0x36] = make_floatx80_init(0x4019, 0xbebc200000000000ULL),  /* 10^8     */
  45     [0x37] = make_floatx80_init(0x4034, 0x8e1bc9bf04000000ULL),  /* 10^16    */
  46     [0x38] = make_floatx80_init(0x4069, 0x9dc5ada82b70b59eULL),  /* 10^32    */
  47     [0x39] = make_floatx80_init(0x40d3, 0xc2781f49ffcfa6d5ULL),  /* 10^64    */
  48     [0x3a] = make_floatx80_init(0x41a8, 0x93ba47c980e98ce0ULL),  /* 10^128   */
  49     [0x3b] = make_floatx80_init(0x4351, 0xaa7eebfb9df9de8eULL),  /* 10^256   */
  50     [0x3c] = make_floatx80_init(0x46a3, 0xe319a0aea60e91c7ULL),  /* 10^512   */
  51     [0x3d] = make_floatx80_init(0x4d48, 0xc976758681750c17ULL),  /* 10^1024  */
  52     [0x3e] = make_floatx80_init(0x5a92, 0x9e8b3b5dc53d5de5ULL),  /* 10^2048  */
  53     [0x3f] = make_floatx80_init(0x7525, 0xc46052028a20979bULL),  /* 10^4096  */
  54 };
  55
  56 int32_t HELPER(reds32)(CPUM68KState *env, FPReg *val)
  57 {
  58     return floatx80_to_int32(val->d, &env->fp_status);
  59 }
  60
  61 float32 HELPER(redf32)(CPUM68KState *env, FPReg *val)
  62 {
  63     return floatx80_to_float32(val->d, &env->fp_status);
  64 }
  65
  66 void HELPER(exts32)(CPUM68KState *env, FPReg *res, int32_t val)
  67 {
  68     res->d = int32_to_floatx80(val, &env->fp_status);
  69 }
  70
  71 void HELPER(extf32)(CPUM68KState *env, FPReg *res, float32 val)
  72 {
  73     res->d = float32_to_floatx80(val, &env->fp_status);
  74 }
  75
  76 void HELPER(extf64)(CPUM68KState *env, FPReg *res, float64 val)
  77 {
  78     res->d = float64_to_floatx80(val, &env->fp_status);
  79 }
  80
  81 float64 HELPER(redf64)(CPUM68KState *env, FPReg *val)
  82 {
  83     return floatx80_to_float64(val->d, &env->fp_status);
  84 }
  85
  86 void HELPER(firound)(CPUM68KState *env, FPReg *res, FPReg *val)
  87 {
  88     res->d = floatx80_round_to_int(val->d, &env->fp_status);
  89 }
  90
  91 static void m68k_restore_precision_mode(CPUM68KState *env)
  92 {
  93     switch (env->fpcr & FPCR_PREC_MASK) {
  94     case FPCR_PREC_X: /* extended */
  95         set_floatx80_rounding_precision(80, &env->fp_status);
  96         break;
  97     case FPCR_PREC_S: /* single */
  98         set_floatx80_rounding_precision(32, &env->fp_status);
  99         break;
 100     case FPCR_PREC_D: /* double */
 101         set_floatx80_rounding_precision(64, &env->fp_status);
 102         break;
 103     case FPCR_PREC_U: /* undefined */
 104     default:
 105         break;
 106     }
 107 }
 108
 109 static void cf_restore_precision_mode(CPUM68KState *env)
 110 {
 111     if (env->fpcr & FPCR_PREC_S) { /* single */
 112         set_floatx80_rounding_precision(32, &env->fp_status);
 113     } else { /* double */
 114         set_floatx80_rounding_precision(64, &env->fp_status);
 115     }
 116 }
 117
 118 static void restore_rounding_mode(CPUM68KState *env)
 119 {
 120     switch (env->fpcr & FPCR_RND_MASK) {
 121     case FPCR_RND_N: /* round to nearest */
 122         set_float_rounding_mode(float_round_nearest_even, &env->fp_status);
 123         break;
 124     case FPCR_RND_Z: /* round to zero */
 125         set_float_rounding_mode(float_round_to_zero, &env->fp_status);
 126         break;
 127     case FPCR_RND_M: /* round toward minus infinity */
 128         set_float_rounding_mode(float_round_down, &env->fp_status);
 129         break;
 130     case FPCR_RND_P: /* round toward positive infinity */
 131         set_float_rounding_mode(float_round_up, &env->fp_status);
 132         break;
 133     }
 134 }
 135
 136 void cpu_m68k_set_fpcr(CPUM68KState *env, uint32_t val)
 137 {
 138     env->fpcr = val & 0xffff;
 139
 140     if (m68k_feature(env, M68K_FEATURE_CF_FPU)) {
 141         cf_restore_precision_mode(env);
 142     } else {
 143         m68k_restore_precision_mode(env);
 144     }
 145     restore_rounding_mode(env);
 146 }
 147
 148 void HELPER(fitrunc)(CPUM68KState *env, FPReg *res, FPReg *val)
 149 {
 150     int rounding_mode = get_float_rounding_mode(&env->fp_status);
 151     set_float_rounding_mode(float_round_to_zero, &env->fp_status);
 152     res->d = floatx80_round_to_int(val->d, &env->fp_status);
 153     set_float_rounding_mode(rounding_mode, &env->fp_status);
 154 }
 155
 156 void HELPER(set_fpcr)(CPUM68KState *env, uint32_t val)
 157 {
 158     cpu_m68k_set_fpcr(env, val);
 159 }
 160
 161 #define PREC_BEGIN(prec)                                        \
 162     do {                                                        \
 163         int old;                                                \
 164         old = get_floatx80_rounding_precision(&env->fp_status); \
 165         set_floatx80_rounding_precision(prec, &env->fp_status)  \
 166
 167 #define PREC_END()                                              \
 168         set_floatx80_rounding_precision(old, &env->fp_status);  \
 169     } while (0)
 170
 171 void HELPER(fsround)(CPUM68KState *env, FPReg *res, FPReg *val)
 172 {
 173     PREC_BEGIN(32);
 174     res->d = floatx80_round(val->d, &env->fp_status);
 175     PREC_END();
 176 }
 177
 178 void HELPER(fdround)(CPUM68KState *env, FPReg *res, FPReg *val)
 179 {
 180     PREC_BEGIN(64);
 181     res->d = floatx80_round(val->d, &env->fp_status);
 182     PREC_END();
 183 }
 184
 185 void HELPER(fsqrt)(CPUM68KState *env, FPReg *res, FPReg *val)
 186 {
 187     res->d = floatx80_sqrt(val->d, &env->fp_status);
 188 }
 189
 190 void HELPER(fssqrt)(CPUM68KState *env, FPReg *res, FPReg *val)
 191 {
 192     PREC_BEGIN(32);
 193     res->d = floatx80_sqrt(val->d, &env->fp_status);
 194     PREC_END();
 195 }
 196
 197 void HELPER(fdsqrt)(CPUM68KState *env, FPReg *res, FPReg *val)
 198 {
 199     PREC_BEGIN(64);
 200     res->d = floatx80_sqrt(val->d, &env->fp_status);
 201     PREC_END();
 202 }
 203
 204 void HELPER(fabs)(CPUM68KState *env, FPReg *res, FPReg *val)
 205 {
 206     res->d = floatx80_round(floatx80_abs(val->d), &env->fp_status);
 207 }
 208
 209 void HELPER(fsabs)(CPUM68KState *env, FPReg *res, FPReg *val)
 210 {
 211     PREC_BEGIN(32);
 212     res->d = floatx80_round(floatx80_abs(val->d), &env->fp_status);
 213     PREC_END();
 214 }
 215
 216 void HELPER(fdabs)(CPUM68KState *env, FPReg *res, FPReg *val)
 217 {
 218     PREC_BEGIN(64);
 219     res->d = floatx80_round(floatx80_abs(val->d), &env->fp_status);
 220     PREC_END();
 221 }
 222
 223 void HELPER(fneg)(CPUM68KState *env, FPReg *res, FPReg *val)
 224 {
 225     res->d = floatx80_round(floatx80_chs(val->d), &env->fp_status);
 226 }
 227
 228 void HELPER(fsneg)(CPUM68KState *env, FPReg *res, FPReg *val)
 229 {
 230     PREC_BEGIN(32);
 231     res->d = floatx80_round(floatx80_chs(val->d), &env->fp_status);
 232     PREC_END();
 233 }
 234
 235 void HELPER(fdneg)(CPUM68KState *env, FPReg *res, FPReg *val)
 236 {
 237     PREC_BEGIN(64);
 238     res->d = floatx80_round(floatx80_chs(val->d), &env->fp_status);
 239     PREC_END();
 240 }
 241
 242 void HELPER(fadd)(CPUM68KState *env, FPReg *res, FPReg *val0, FPReg *val1)
 243 {
 244     res->d = floatx80_add(val0->d, val1->d, &env->fp_status);
 245 }
 246
 247 void HELPER(fsadd)(CPUM68KState *env, FPReg *res, FPReg *val0, FPReg *val1)
 248 {
 249     PREC_BEGIN(32);
 250     res->d = floatx80_add(val0->d, val1->d, &env->fp_status);
 251     PREC_END();
 252 }
 253
 254 void HELPER(fdadd)(CPUM68KState *env, FPReg *res, FPReg *val0, FPReg *val1)
 255 {
 256     PREC_BEGIN(64);
 257     res->d = floatx80_add(val0->d, val1->d, &env->fp_status);
 258     PREC_END();
 259 }
 260
 261 void HELPER(fsub)(CPUM68KState *env, FPReg *res, FPReg *val0, FPReg *val1)
 262 {
 263     res->d = floatx80_sub(val1->d, val0->d, &env->fp_status);
 264 }
 265
 266 void HELPER(fssub)(CPUM68KState *env, FPReg *res, FPReg *val0, FPReg *val1)
 267 {
 268     PREC_BEGIN(32);
 269     res->d = floatx80_sub(val1->d, val0->d, &env->fp_status);
 270     PREC_END();
 271 }
 272
 273 void HELPER(fdsub)(CPUM68KState *env, FPReg *res, FPReg *val0, FPReg *val1)
 274 {
 275     PREC_BEGIN(64);
 276     res->d = floatx80_sub(val1->d, val0->d, &env->fp_status);
 277     PREC_END();
 278 }
 279
 280 void HELPER(fmul)(CPUM68KState *env, FPReg *res, FPReg *val0, FPReg *val1)
 281 {
 282     res->d = floatx80_mul(val0->d, val1->d, &env->fp_status);
 283 }
 284
 285 void HELPER(fsmul)(CPUM68KState *env, FPReg *res, FPReg *val0, FPReg *val1)
 286 {
 287     PREC_BEGIN(32);
 288     res->d = floatx80_mul(val0->d, val1->d, &env->fp_status);
 289     PREC_END();
 290 }
 291
 292 void HELPER(fdmul)(CPUM68KState *env, FPReg *res, FPReg *val0, FPReg *val1)
 293 {
 294     PREC_BEGIN(64);
 295     res->d = floatx80_mul(val0->d, val1->d, &env->fp_status);
 296     PREC_END();
 297 }
 298
 299 void HELPER(fsglmul)(CPUM68KState *env, FPReg *res, FPReg *val0, FPReg *val1)
 300 {
 301     int rounding_mode = get_float_rounding_mode(&env->fp_status);
 302     floatx80 a, b;
 303
 304     PREC_BEGIN(32);
 305     set_float_rounding_mode(float_round_to_zero, &env->fp_status);
 306     a = floatx80_round(val0->d, &env->fp_status);
 307     b = floatx80_round(val1->d, &env->fp_status);
 308     set_float_rounding_mode(rounding_mode, &env->fp_status);
 309     res->d = floatx80_mul(a, b, &env->fp_status);
 310     PREC_END();
 311 }
 312
 313 void HELPER(fdiv)(CPUM68KState *env, FPReg *res, FPReg *val0, FPReg *val1)
 314 {
 315     res->d = floatx80_div(val1->d, val0->d, &env->fp_status);
 316 }
 317
 318 void HELPER(fsdiv)(CPUM68KState *env, FPReg *res, FPReg *val0, FPReg *val1)
 319 {
 320     PREC_BEGIN(32);
 321     res->d = floatx80_div(val1->d, val0->d, &env->fp_status);
 322     PREC_END();
 323 }
 324
 325 void HELPER(fddiv)(CPUM68KState *env, FPReg *res, FPReg *val0, FPReg *val1)
 326 {
 327     PREC_BEGIN(64);
 328     res->d = floatx80_div(val1->d, val0->d, &env->fp_status);
 329     PREC_END();
 330 }
 331
 332 void HELPER(fsgldiv)(CPUM68KState *env, FPReg *res, FPReg *val0, FPReg *val1)
 333 {
 334     int rounding_mode = get_float_rounding_mode(&env->fp_status);
 335     floatx80 a, b;
 336
 337     PREC_BEGIN(32);
 338     set_float_rounding_mode(float_round_to_zero, &env->fp_status);
 339     a = floatx80_round(val1->d, &env->fp_status);
 340     b = floatx80_round(val0->d, &env->fp_status);
 341     set_float_rounding_mode(rounding_mode, &env->fp_status);
 342     res->d = floatx80_div(a, b, &env->fp_status);
 343     PREC_END();
 344 }
 345
 346 static int float_comp_to_cc(int float_compare)
 347 {
 348     switch (float_compare) {
 349     case float_relation_equal:
 350         return FPSR_CC_Z;
 351     case float_relation_less:
 352         return FPSR_CC_N;
 353     case float_relation_unordered:
 354         return FPSR_CC_A;
 355     case float_relation_greater:
 356         return 0;
 357     default:
 358         g_assert_not_reached();
 359     }
 360 }
 361
 362 void HELPER(fcmp)(CPUM68KState *env, FPReg *val0, FPReg *val1)
 363 {
 364     int float_compare;
 365
 366     float_compare = floatx80_compare(val1->d, val0->d, &env->fp_status);
 367     env->fpsr = (env->fpsr & ~FPSR_CC_MASK) | float_comp_to_cc(float_compare);
 368 }
 369
 370 void HELPER(ftst)(CPUM68KState *env, FPReg *val)
 371 {
 372     uint32_t cc = 0;
 373
 374     if (floatx80_is_neg(val->d)) {
 375         cc |= FPSR_CC_N;
 376     }
 377
 378     if (floatx80_is_any_nan(val->d)) {
 379         cc |= FPSR_CC_A;
 380     } else if (floatx80_is_infinity(val->d)) {
 381         cc |= FPSR_CC_I;
 382     } else if (floatx80_is_zero(val->d)) {
 383         cc |= FPSR_CC_Z;
 384     }
 385     env->fpsr = (env->fpsr & ~FPSR_CC_MASK) | cc;
 386 }
 387
 388 void HELPER(fconst)(CPUM68KState *env, FPReg *val, uint32_t offset)
 389 {
 390     val->d = fpu_rom[offset];
 391 }
 392
 393 typedef int (*float_access)(CPUM68KState *env, uint32_t addr, FPReg *fp,
 394                             uintptr_t ra);
 395
 396 static uint32_t fmovem_predec(CPUM68KState *env, uint32_t addr, uint32_t mask,
 397                                float_access access)
 398 {
 399     uintptr_t ra = GETPC();
 400     int i, size;
 401
 402     for (i = 7; i >= 0; i--, mask <<= 1) {
 403         if (mask & 0x80) {
 404             size = access(env, addr, &env->fregs[i], ra);
 405             if ((mask & 0xff) != 0x80) {
 406                 addr -= size;
 407             }
 408         }
 409     }
 410
 411     return addr;
 412 }
 413
 414 static uint32_t fmovem_postinc(CPUM68KState *env, uint32_t addr, uint32_t mask,
 415                                float_access access)
 416 {
 417     uintptr_t ra = GETPC();
 418     int i, size;
 419
 420     for (i = 0; i < 8; i++, mask <<= 1) {
 421         if (mask & 0x80) {
 422             size = access(env, addr, &env->fregs[i], ra);
 423             addr += size;
 424         }
 425     }
 426
 427     return addr;
 428 }
 429
 430 static int cpu_ld_floatx80_ra(CPUM68KState *env, uint32_t addr, FPReg *fp,
 431                               uintptr_t ra)
 432 {
 433     uint32_t high;
 434     uint64_t low;
 435
 436     high = cpu_ldl_data_ra(env, addr, ra);
 437     low = cpu_ldq_data_ra(env, addr + 4, ra);
 438
 439     fp->l.upper = high >> 16;
 440     fp->l.lower = low;
 441
 442     return 12;
 443 }
 444
 445 static int cpu_st_floatx80_ra(CPUM68KState *env, uint32_t addr, FPReg *fp,
 446                                uintptr_t ra)
 447 {
 448     cpu_stl_data_ra(env, addr, fp->l.upper << 16, ra);
 449     cpu_stq_data_ra(env, addr + 4, fp->l.lower, ra);
 450
 451     return 12;
 452 }
 453
 454 static int cpu_ld_float64_ra(CPUM68KState *env, uint32_t addr, FPReg *fp,
 455                              uintptr_t ra)
 456 {
 457     uint64_t val;
 458
 459     val = cpu_ldq_data_ra(env, addr, ra);
 460     fp->d = float64_to_floatx80(*(float64 *)&val, &env->fp_status);
 461
 462     return 8;
 463 }
 464
 465 static int cpu_st_float64_ra(CPUM68KState *env, uint32_t addr, FPReg *fp,
 466                              uintptr_t ra)
 467 {
 468     float64 val;
 469
 470     val = floatx80_to_float64(fp->d, &env->fp_status);
 471     cpu_stq_data_ra(env, addr, *(uint64_t *)&val, ra);
 472
 473     return 8;
 474 }
 475
 476 uint32_t HELPER(fmovemx_st_predec)(CPUM68KState *env, uint32_t addr,
 477                                    uint32_t mask)
 478 {
 479     return fmovem_predec(env, addr, mask, cpu_st_floatx80_ra);
 480 }
 481
 482 uint32_t HELPER(fmovemx_st_postinc)(CPUM68KState *env, uint32_t addr,
 483                                     uint32_t mask)
 484 {
 485     return fmovem_postinc(env, addr, mask, cpu_st_floatx80_ra);
 486 }
 487
 488 uint32_t HELPER(fmovemx_ld_postinc)(CPUM68KState *env, uint32_t addr,
 489                                     uint32_t mask)
 490 {
 491     return fmovem_postinc(env, addr, mask, cpu_ld_floatx80_ra);
 492 }
 493
 494 uint32_t HELPER(fmovemd_st_predec)(CPUM68KState *env, uint32_t addr,
 495                                    uint32_t mask)
 496 {
 497     return fmovem_predec(env, addr, mask, cpu_st_float64_ra);
 498 }
 499
 500 uint32_t HELPER(fmovemd_st_postinc)(CPUM68KState *env, uint32_t addr,
 501                                     uint32_t mask)
 502 {
 503     return fmovem_postinc(env, addr, mask, cpu_st_float64_ra);
 504 }
 505
 506 uint32_t HELPER(fmovemd_ld_postinc)(CPUM68KState *env, uint32_t addr,
 507                                     uint32_t mask)
 508 {
 509     return fmovem_postinc(env, addr, mask, cpu_ld_float64_ra);
 510 }