target-arm/op_helper.c

   1 /*
   2  *  ARM helper routines
   3  *
   4  *  Copyright (c) 2005-2007 CodeSourcery, LLC
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2 of the License, or (at your option) any later version.
  10  *
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, write to the Free Software
  18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19  */
  20 #include "exec.h"
  21 #include "helpers.h"
  22
  23 #define SIGNBIT (uint32_t)0x80000000
  24 #define SIGNBIT64 ((uint64_t)1 << 63)
  25
  26 void raise_exception(int tt)
  27 {
  28     env->exception_index = tt;
  29     cpu_loop_exit();
  30 }
  31
  32 /* thread support */
  33
  34 spinlock_t global_cpu_lock = SPIN_LOCK_UNLOCKED;
  35
  36 void cpu_lock(void)
  37 {
  38     spin_lock(&global_cpu_lock);
  39 }
  40
  41 void cpu_unlock(void)
  42 {
  43     spin_unlock(&global_cpu_lock);
  44 }
  45
  46 uint32_t HELPER(neon_tbl)(uint32_t ireg, uint32_t def,
  47                           uint32_t rn, uint32_t maxindex)
  48 {
  49     uint32_t val;
  50     uint32_t tmp;
  51     int index;
  52     int shift;
  53     uint64_t *table;
  54     table = (uint64_t *)&env->vfp.regs[rn];
  55     val = 0;
  56     for (shift = 0; shift < 32; shift += 8) {
  57         index = (ireg >> shift) & 0xff;
  58         if (index < maxindex) {
  59             tmp = (table[index >> 3] >> (index & 7)) & 0xff;
  60             val |= tmp << shift;
  61         } else {
  62             val |= def & (0xff << shift);
  63         }
  64     }
  65     return val;
  66 }
  67
  68 #if !defined(CONFIG_USER_ONLY)
  69
  70 #define MMUSUFFIX _mmu
  71
  72 #define SHIFT 0
  73 #include "softmmu_template.h"
  74
  75 #define SHIFT 1
  76 #include "softmmu_template.h"
  77
  78 #define SHIFT 2
  79 #include "softmmu_template.h"
  80
  81 #define SHIFT 3
  82 #include "softmmu_template.h"
  83
  84 /* try to fill the TLB and return an exception if error. If retaddr is
  85    NULL, it means that the function was called in C code (i.e. not
  86    from generated code or from helper.c) */
  87 /* XXX: fix it to restore all registers */
  88 void tlb_fill (target_ulong addr, int is_write, int mmu_idx, void *retaddr)
  89 {
  90     TranslationBlock *tb;
  91     CPUState *saved_env;
  92     unsigned long pc;
  93     int ret;
  94
  95     /* XXX: hack to restore env in all cases, even if not called from
  96        generated code */
  97     saved_env = env;
  98     env = cpu_single_env;
  99     ret = cpu_arm_handle_mmu_fault(env, addr, is_write, mmu_idx, 1);
 100     if (__builtin_expect(ret, 0)) {
 101         if (retaddr) {
 102             /* now we have a real cpu fault */
 103             pc = (unsigned long)retaddr;
 104             tb = tb_find_pc(pc);
 105             if (tb) {
 106                 /* the PC is inside the translated code. It means that we have
 107                    a virtual CPU fault */
 108                 cpu_restore_state(tb, env, pc, NULL);
 109             }
 110         }
 111         raise_exception(env->exception_index);
 112     }
 113     env = saved_env;
 114 }
 115 #endif
 116
 117 /* FIXME: Pass an axplicit pointer to QF to CPUState, and move saturating
 118    instructions into helper.c  */
 119 uint32_t HELPER(add_setq)(uint32_t a, uint32_t b)
 120 {
 121     uint32_t res = a + b;
 122     if (((res ^ a) & SIGNBIT) && !((a ^ b) & SIGNBIT))
 123         env->QF = 1;
 124     return res;
 125 }
 126
 127 uint32_t HELPER(add_saturate)(uint32_t a, uint32_t b)
 128 {
 129     uint32_t res = a + b;
 130     if (((res ^ a) & SIGNBIT) && !((a ^ b) & SIGNBIT)) {
 131         env->QF = 1;
 132         res = ~(((int32_t)a >> 31) ^ SIGNBIT);
 133     }
 134     return res;
 135 }
 136
 137 uint32_t HELPER(sub_saturate)(uint32_t a, uint32_t b)
 138 {
 139     uint32_t res = a - b;
 140     if (((res ^ a) & SIGNBIT) && ((a ^ b) & SIGNBIT)) {
 141         env->QF = 1;
 142         res = ~(((int32_t)a >> 31) ^ SIGNBIT);
 143     }
 144     return res;
 145 }
 146
 147 uint32_t HELPER(double_saturate)(int32_t val)
 148 {
 149     uint32_t res;
 150     if (val >= 0x40000000) {
 151         res = ~SIGNBIT;
 152         env->QF = 1;
 153     } else if (val <= (int32_t)0xc0000000) {
 154         res = SIGNBIT;
 155         env->QF = 1;
 156     } else {
 157         res = val << 1;
 158     }
 159     return res;
 160 }
 161
 162 uint32_t HELPER(add_usaturate)(uint32_t a, uint32_t b)
 163 {
 164     uint32_t res = a + b;
 165     if (res < a) {
 166         env->QF = 1;
 167         res = ~0;
 168     }
 169     return res;
 170 }
 171
 172 uint32_t HELPER(sub_usaturate)(uint32_t a, uint32_t b)
 173 {
 174     uint32_t res = a - b;
 175     if (res > a) {
 176         env->QF = 1;
 177         res = 0;
 178     }
 179     return res;
 180 }
 181
 182 /* Signed saturation.  */
 183 static inline uint32_t do_ssat(int32_t val, int shift)
 184 {
 185     int32_t top;
 186     uint32_t mask;
 187
 188     shift = PARAM1;
 189     top = val >> shift;
 190     mask = (1u << shift) - 1;
 191     if (top > 0) {
 192         env->QF = 1;
 193         return mask;
 194     } else if (top < -1) {
 195         env->QF = 1;
 196         return ~mask;
 197     }
 198     return val;
 199 }
 200
 201 /* Unsigned saturation.  */
 202 static inline uint32_t do_usat(int32_t val, int shift)
 203 {
 204     uint32_t max;
 205
 206     shift = PARAM1;
 207     max = (1u << shift) - 1;
 208     if (val < 0) {
 209         env->QF = 1;
 210         return 0;
 211     } else if (val > max) {
 212         env->QF = 1;
 213         return max;
 214     }
 215     return val;
 216 }
 217
 218 /* Signed saturate.  */
 219 uint32_t HELPER(ssat)(uint32_t x, uint32_t shift)
 220 {
 221     return do_ssat(x, shift);
 222 }
 223
 224 /* Dual halfword signed saturate.  */
 225 uint32_t HELPER(ssat16)(uint32_t x, uint32_t shift)
 226 {
 227     uint32_t res;
 228
 229     res = (uint16_t)do_ssat((int16_t)x, shift);
 230     res |= do_ssat(((int32_t)x) >> 16, shift) << 16;
 231     return res;
 232 }
 233
 234 /* Unsigned saturate.  */
 235 uint32_t HELPER(usat)(uint32_t x, uint32_t shift)
 236 {
 237     return do_usat(x, shift);
 238 }
 239
 240 /* Dual halfword unsigned saturate.  */
 241 uint32_t HELPER(usat16)(uint32_t x, uint32_t shift)
 242 {
 243     uint32_t res;
 244
 245     res = (uint16_t)do_usat((int16_t)x, shift);
 246     res |= do_usat(((int32_t)x) >> 16, shift) << 16;
 247     return res;
 248 }
 249
 250 void HELPER(wfi)(void)
 251 {
 252     env->exception_index = EXCP_HLT;
 253     env->halted = 1;
 254     cpu_loop_exit();
 255 }
 256
 257 void HELPER(exception)(uint32_t excp)
 258 {
 259     env->exception_index = excp;
 260     cpu_loop_exit();
 261 }
 262
 263 uint32_t HELPER(cpsr_read)(void)
 264 {
 265     return cpsr_read(env) & ~CPSR_EXEC;
 266 }
 267
 268 void HELPER(cpsr_write)(uint32_t val, uint32_t mask)
 269 {
 270     cpsr_write(env, val, mask);
 271 }
 272
 273 /* Access to user mode registers from privileged modes.  */
 274 uint32_t HELPER(get_user_reg)(uint32_t regno)
 275 {
 276     uint32_t val;
 277
 278     if (regno == 13) {
 279         val = env->banked_r13[0];
 280     } else if (regno == 14) {
 281         val = env->banked_r14[0];
 282     } else if (regno >= 8
 283                && (env->uncached_cpsr & 0x1f) == ARM_CPU_MODE_FIQ) {
 284         val = env->usr_regs[regno - 8];
 285     } else {
 286         val = env->regs[regno];
 287     }
 288     return val;
 289 }
 290
 291 void HELPER(set_user_reg)(uint32_t regno, uint32_t val)
 292 {
 293     if (regno == 13) {
 294         env->banked_r13[0] = val;
 295     } else if (regno == 14) {
 296         env->banked_r14[0] = val;
 297     } else if (regno >= 8
 298                && (env->uncached_cpsr & 0x1f) == ARM_CPU_MODE_FIQ) {
 299         env->usr_regs[regno - 8] = val;
 300     } else {
 301         env->regs[regno] = val;
 302     }
 303 }
 304
 305 /* ??? Flag setting arithmetic is awkward because we need to do comparisons.
 306    The only way to do that in TCG is a conditional branch, which clobbers
 307    all our temporaries.  For now implement these as helper functions.  */
 308
 309 uint32_t HELPER (add_cc)(uint32_t a, uint32_t b)
 310 {
 311     uint32_t result;
 312     result = T0 + T1;
 313     env->NF = env->ZF = result;
 314     env->CF = result < a;
 315     env->VF = (a ^ b ^ -1) & (a ^ result);
 316     return result;
 317 }
 318
 319 uint32_t HELPER(adc_cc)(uint32_t a, uint32_t b)
 320 {
 321     uint32_t result;
 322     if (!env->CF) {
 323         result = a + b;
 324         env->CF = result < a;
 325     } else {
 326         result = a + b + 1;
 327         env->CF = result <= a;
 328     }
 329     env->VF = (a ^ b ^ -1) & (a ^ result);
 330     env->NF = env->ZF = result;
 331     return result;
 332 }
 333
 334 uint32_t HELPER(sub_cc)(uint32_t a, uint32_t b)
 335 {
 336     uint32_t result;
 337     result = a - b;
 338     env->NF = env->ZF = result;
 339     env->CF = a >= b;
 340     env->VF = (a ^ b) & (a ^ result);
 341     return result;
 342 }
 343
 344 uint32_t HELPER(sbc_cc)(uint32_t a, uint32_t b)
 345 {
 346     uint32_t result;
 347     if (!env->CF) {
 348         result = a - b - 1;
 349         env->CF = a > b;
 350     } else {
 351         result = a - b;
 352         env->CF = a >= b;
 353     }
 354     env->VF = (a ^ b) & (a ^ result);
 355     env->NF = env->ZF = result;
 356     return result;
 357 }
 358
 359 /* Similarly for variable shift instructions.  */
 360
 361 uint32_t HELPER(shl)(uint32_t x, uint32_t i)
 362 {
 363     int shift = i & 0xff;
 364     if (shift >= 32)
 365         return 0;
 366     return x << shift;
 367 }
 368
 369 uint32_t HELPER(shr)(uint32_t x, uint32_t i)
 370 {
 371     int shift = i & 0xff;
 372     if (shift >= 32)
 373         return 0;
 374     return (uint32_t)x >> shift;
 375 }
 376
 377 uint32_t HELPER(sar)(uint32_t x, uint32_t i)
 378 {
 379     int shift = i & 0xff;
 380     if (shift >= 32)
 381         shift = 31;
 382     return (int32_t)x >> shift;
 383 }
 384
 385 uint32_t HELPER(ror)(uint32_t x, uint32_t i)
 386 {
 387     int shift = i & 0xff;
 388     if (shift == 0)
 389         return x;
 390     return (x >> shift) | (x << (32 - shift));
 391 }
 392
 393 uint32_t HELPER(shl_cc)(uint32_t x, uint32_t i)
 394 {
 395     int shift = i & 0xff;
 396     if (shift >= 32) {
 397         if (shift == 32)
 398             env->CF = x & 1;
 399         else
 400             env->CF = 0;
 401         return 0;
 402     } else if (shift != 0) {
 403         env->CF = (x >> (32 - shift)) & 1;
 404         return x << shift;
 405     }
 406     return x;
 407 }
 408
 409 uint32_t HELPER(shr_cc)(uint32_t x, uint32_t i)
 410 {
 411     int shift = i & 0xff;
 412     if (shift >= 32) {
 413         if (shift == 32)
 414             env->CF = (x >> 31) & 1;
 415         else
 416             env->CF = 0;
 417         return 0;
 418     } else if (shift != 0) {
 419         env->CF = (x >> (shift - 1)) & 1;
 420         return x >> shift;
 421     }
 422     return x;
 423 }
 424
 425 uint32_t HELPER(sar_cc)(uint32_t x, uint32_t i)
 426 {
 427     int shift = i & 0xff;
 428     if (shift >= 32) {
 429         env->CF = (x >> 31) & 1;
 430         return (int32_t)x >> 31;
 431     } else if (shift != 0) {
 432         env->CF = (x >> (shift - 1)) & 1;
 433         return (int32_t)x >> shift;
 434     }
 435     return x;
 436 }
 437
 438 uint32_t HELPER(ror_cc)(uint32_t x, uint32_t i)
 439 {
 440     int shift1, shift;
 441     shift1 = i & 0xff;
 442     shift = shift1 & 0x1f;
 443     if (shift == 0) {
 444         if (shift1 != 0)
 445             env->CF = (x >> 31) & 1;
 446         return x;
 447     } else {
 448         env->CF = (x >> (shift - 1)) & 1;
 449         return ((uint32_t)x >> shift) | (x << (32 - shift));
 450     }
 451 }
 452
 453 uint64_t HELPER(neon_add_saturate_s64)(uint64_t src1, uint64_t src2)
 454 {
 455     uint64_t res;
 456
 457     res = src1 + src2;
 458     if (((res ^ src1) & SIGNBIT64) && !((src1 ^ src2) & SIGNBIT64)) {
 459         env->QF = 1;
 460         res = ((int64_t)src1 >> 63) ^ ~SIGNBIT64;
 461     }
 462     return res;
 463 }
 464
 465 uint64_t HELPER(neon_add_saturate_u64)(uint64_t src1, uint64_t src2)
 466 {
 467     uint64_t res;
 468
 469     res = src1 + src2;
 470     if (res < src1) {
 471         env->QF = 1;
 472         res = ~(uint64_t)0;
 473     }
 474     return res;
 475 }
 476
 477 uint64_t HELPER(neon_sub_saturate_s64)(uint64_t src1, uint64_t src2)
 478 {
 479     uint64_t res;
 480
 481     res = src1 - src2;
 482     if (((res ^ src1) & SIGNBIT64) && ((src1 ^ src2) & SIGNBIT64)) {
 483         env->QF = 1;
 484         res = ((int64_t)src1 >> 63) ^ ~SIGNBIT64;
 485     }
 486     return res;
 487 }
 488
 489 uint64_t HELPER(neon_sub_saturate_u64)(uint64_t src1, uint64_t src2)
 490 {
 491     uint64_t res;
 492
 493     if (src1 < src2) {
 494         env->QF = 1;
 495         res = 0;
 496     } else {
 497         res = src1 - src2;
 498     }
 499     return res;
 500 }
 501
 502 /* These need to return a pair of value, so still use T0/T1.  */
 503 /* Transpose.  Argument order is rather strange to avoid special casing
 504    the tranlation code.
 505    On input T0 = rm, T1 = rd.  On output T0 = rd, T1 = rm  */
 506 void HELPER(neon_trn_u8)(void)
 507 {
 508     uint32_t rd;
 509     uint32_t rm;
 510     rd = ((T0 & 0x00ff00ff) << 8) | (T1 & 0x00ff00ff);
 511     rm = ((T1 & 0xff00ff00) >> 8) | (T0 & 0xff00ff00);
 512     T0 = rd;
 513     T1 = rm;
 514     FORCE_RET();
 515 }
 516
 517 void HELPER(neon_trn_u16)(void)
 518 {
 519     uint32_t rd;
 520     uint32_t rm;
 521     rd = (T0 << 16) | (T1 & 0xffff);
 522     rm = (T1 >> 16) | (T0 & 0xffff0000);
 523     T0 = rd;
 524     T1 = rm;
 525     FORCE_RET();
 526 }
 527
 528 /* Worker routines for zip and unzip.  */
 529 void HELPER(neon_unzip_u8)(void)
 530 {
 531     uint32_t rd;
 532     uint32_t rm;
 533     rd = (T0 & 0xff) | ((T0 >> 8) & 0xff00)
 534          | ((T1 << 16) & 0xff0000) | ((T1 << 8) & 0xff000000);
 535     rm = ((T0 >> 8) & 0xff) | ((T0 >> 16) & 0xff00)
 536          | ((T1 << 8) & 0xff0000) | (T1 & 0xff000000);
 537     T0 = rd;
 538     T1 = rm;
 539     FORCE_RET();
 540 }
 541
 542 void HELPER(neon_zip_u8)(void)
 543 {
 544     uint32_t rd;
 545     uint32_t rm;
 546     rd = (T0 & 0xff) | ((T1 << 8) & 0xff00)
 547          | ((T0 << 16) & 0xff0000) | ((T1 << 24) & 0xff000000);
 548     rm = ((T0 >> 16) & 0xff) | ((T1 >> 8) & 0xff00)
 549          | ((T0 >> 8) & 0xff0000) | (T1 & 0xff000000);
 550     T0 = rd;
 551     T1 = rm;
 552     FORCE_RET();
 553 }
 554
 555 void HELPER(neon_zip_u16)(void)
 556 {
 557     uint32_t tmp;
 558
 559     tmp = (T0 & 0xffff) | (T1 << 16);
 560     T1 = (T1 & 0xffff0000) | (T0 >> 16);
 561     T0 = tmp;
 562     FORCE_RET();
 563 }