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., 51 Franklin Street, Fifth Floor, Boston MA  02110-1301 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 static 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) << 3)) & 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 (unlikely(ret)) {
 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     top = val >> shift;
 189     mask = (1u << shift) - 1;
 190     if (top > 0) {
 191         env->QF = 1;
 192         return mask;
 193     } else if (top < -1) {
 194         env->QF = 1;
 195         return ~mask;
 196     }
 197     return val;
 198 }
 199
 200 /* Unsigned saturation.  */
 201 static inline uint32_t do_usat(int32_t val, int shift)
 202 {
 203     uint32_t max;
 204
 205     max = (1u << shift) - 1;
 206     if (val < 0) {
 207         env->QF = 1;
 208         return 0;
 209     } else if (val > max) {
 210         env->QF = 1;
 211         return max;
 212     }
 213     return val;
 214 }
 215
 216 /* Signed saturate.  */
 217 uint32_t HELPER(ssat)(uint32_t x, uint32_t shift)
 218 {
 219     return do_ssat(x, shift);
 220 }
 221
 222 /* Dual halfword signed saturate.  */
 223 uint32_t HELPER(ssat16)(uint32_t x, uint32_t shift)
 224 {
 225     uint32_t res;
 226
 227     res = (uint16_t)do_ssat((int16_t)x, shift);
 228     res |= do_ssat(((int32_t)x) >> 16, shift) << 16;
 229     return res;
 230 }
 231
 232 /* Unsigned saturate.  */
 233 uint32_t HELPER(usat)(uint32_t x, uint32_t shift)
 234 {
 235     return do_usat(x, shift);
 236 }
 237
 238 /* Dual halfword unsigned saturate.  */
 239 uint32_t HELPER(usat16)(uint32_t x, uint32_t shift)
 240 {
 241     uint32_t res;
 242
 243     res = (uint16_t)do_usat((int16_t)x, shift);
 244     res |= do_usat(((int32_t)x) >> 16, shift) << 16;
 245     return res;
 246 }
 247
 248 void HELPER(wfi)(void)
 249 {
 250     env->exception_index = EXCP_HLT;
 251     env->halted = 1;
 252     cpu_loop_exit();
 253 }
 254
 255 void HELPER(exception)(uint32_t excp)
 256 {
 257     env->exception_index = excp;
 258     cpu_loop_exit();
 259 }
 260
 261 uint32_t HELPER(cpsr_read)(void)
 262 {
 263     return cpsr_read(env) & ~CPSR_EXEC;
 264 }
 265
 266 void HELPER(cpsr_write)(uint32_t val, uint32_t mask)
 267 {
 268     cpsr_write(env, val, mask);
 269 }
 270
 271 /* Access to user mode registers from privileged modes.  */
 272 uint32_t HELPER(get_user_reg)(uint32_t regno)
 273 {
 274     uint32_t val;
 275
 276     if (regno == 13) {
 277         val = env->banked_r13[0];
 278     } else if (regno == 14) {
 279         val = env->banked_r14[0];
 280     } else if (regno >= 8
 281                && (env->uncached_cpsr & 0x1f) == ARM_CPU_MODE_FIQ) {
 282         val = env->usr_regs[regno - 8];
 283     } else {
 284         val = env->regs[regno];
 285     }
 286     return val;
 287 }
 288
 289 void HELPER(set_user_reg)(uint32_t regno, uint32_t val)
 290 {
 291     if (regno == 13) {
 292         env->banked_r13[0] = val;
 293     } else if (regno == 14) {
 294         env->banked_r14[0] = val;
 295     } else if (regno >= 8
 296                && (env->uncached_cpsr & 0x1f) == ARM_CPU_MODE_FIQ) {
 297         env->usr_regs[regno - 8] = val;
 298     } else {
 299         env->regs[regno] = val;
 300     }
 301 }
 302
 303 /* ??? Flag setting arithmetic is awkward because we need to do comparisons.
 304    The only way to do that in TCG is a conditional branch, which clobbers
 305    all our temporaries.  For now implement these as helper functions.  */
 306
 307 uint32_t HELPER (add_cc)(uint32_t a, uint32_t b)
 308 {
 309     uint32_t result;
 310     result = T0 + T1;
 311     env->NF = env->ZF = result;
 312     env->CF = result < a;
 313     env->VF = (a ^ b ^ -1) & (a ^ result);
 314     return result;
 315 }
 316
 317 uint32_t HELPER(adc_cc)(uint32_t a, uint32_t b)
 318 {
 319     uint32_t result;
 320     if (!env->CF) {
 321         result = a + b;
 322         env->CF = result < a;
 323     } else {
 324         result = a + b + 1;
 325         env->CF = result <= a;
 326     }
 327     env->VF = (a ^ b ^ -1) & (a ^ result);
 328     env->NF = env->ZF = result;
 329     return result;
 330 }
 331
 332 uint32_t HELPER(sub_cc)(uint32_t a, uint32_t b)
 333 {
 334     uint32_t result;
 335     result = a - b;
 336     env->NF = env->ZF = result;
 337     env->CF = a >= b;
 338     env->VF = (a ^ b) & (a ^ result);
 339     return result;
 340 }
 341
 342 uint32_t HELPER(sbc_cc)(uint32_t a, uint32_t b)
 343 {
 344     uint32_t result;
 345     if (!env->CF) {
 346         result = a - b - 1;
 347         env->CF = a > b;
 348     } else {
 349         result = a - b;
 350         env->CF = a >= b;
 351     }
 352     env->VF = (a ^ b) & (a ^ result);
 353     env->NF = env->ZF = result;
 354     return result;
 355 }
 356
 357 /* Similarly for variable shift instructions.  */
 358
 359 uint32_t HELPER(shl)(uint32_t x, uint32_t i)
 360 {
 361     int shift = i & 0xff;
 362     if (shift >= 32)
 363         return 0;
 364     return x << shift;
 365 }
 366
 367 uint32_t HELPER(shr)(uint32_t x, uint32_t i)
 368 {
 369     int shift = i & 0xff;
 370     if (shift >= 32)
 371         return 0;
 372     return (uint32_t)x >> shift;
 373 }
 374
 375 uint32_t HELPER(sar)(uint32_t x, uint32_t i)
 376 {
 377     int shift = i & 0xff;
 378     if (shift >= 32)
 379         shift = 31;
 380     return (int32_t)x >> shift;
 381 }
 382
 383 uint32_t HELPER(ror)(uint32_t x, uint32_t i)
 384 {
 385     int shift = i & 0xff;
 386     if (shift == 0)
 387         return x;
 388     return (x >> shift) | (x << (32 - shift));
 389 }
 390
 391 uint32_t HELPER(shl_cc)(uint32_t x, uint32_t i)
 392 {
 393     int shift = i & 0xff;
 394     if (shift >= 32) {
 395         if (shift == 32)
 396             env->CF = x & 1;
 397         else
 398             env->CF = 0;
 399         return 0;
 400     } else if (shift != 0) {
 401         env->CF = (x >> (32 - shift)) & 1;
 402         return x << shift;
 403     }
 404     return x;
 405 }
 406
 407 uint32_t HELPER(shr_cc)(uint32_t x, uint32_t i)
 408 {
 409     int shift = i & 0xff;
 410     if (shift >= 32) {
 411         if (shift == 32)
 412             env->CF = (x >> 31) & 1;
 413         else
 414             env->CF = 0;
 415         return 0;
 416     } else if (shift != 0) {
 417         env->CF = (x >> (shift - 1)) & 1;
 418         return x >> shift;
 419     }
 420     return x;
 421 }
 422
 423 uint32_t HELPER(sar_cc)(uint32_t x, uint32_t i)
 424 {
 425     int shift = i & 0xff;
 426     if (shift >= 32) {
 427         env->CF = (x >> 31) & 1;
 428         return (int32_t)x >> 31;
 429     } else if (shift != 0) {
 430         env->CF = (x >> (shift - 1)) & 1;
 431         return (int32_t)x >> shift;
 432     }
 433     return x;
 434 }
 435
 436 uint32_t HELPER(ror_cc)(uint32_t x, uint32_t i)
 437 {
 438     int shift1, shift;
 439     shift1 = i & 0xff;
 440     shift = shift1 & 0x1f;
 441     if (shift == 0) {
 442         if (shift1 != 0)
 443             env->CF = (x >> 31) & 1;
 444         return x;
 445     } else {
 446         env->CF = (x >> (shift - 1)) & 1;
 447         return ((uint32_t)x >> shift) | (x << (32 - shift));
 448     }
 449 }
 450
 451 uint64_t HELPER(neon_add_saturate_s64)(uint64_t src1, uint64_t src2)
 452 {
 453     uint64_t res;
 454
 455     res = src1 + src2;
 456     if (((res ^ src1) & SIGNBIT64) && !((src1 ^ src2) & SIGNBIT64)) {
 457         env->QF = 1;
 458         res = ((int64_t)src1 >> 63) ^ ~SIGNBIT64;
 459     }
 460     return res;
 461 }
 462
 463 uint64_t HELPER(neon_add_saturate_u64)(uint64_t src1, uint64_t src2)
 464 {
 465     uint64_t res;
 466
 467     res = src1 + src2;
 468     if (res < src1) {
 469         env->QF = 1;
 470         res = ~(uint64_t)0;
 471     }
 472     return res;
 473 }
 474
 475 uint64_t HELPER(neon_sub_saturate_s64)(uint64_t src1, uint64_t src2)
 476 {
 477     uint64_t res;
 478
 479     res = src1 - src2;
 480     if (((res ^ src1) & SIGNBIT64) && ((src1 ^ src2) & SIGNBIT64)) {
 481         env->QF = 1;
 482         res = ((int64_t)src1 >> 63) ^ ~SIGNBIT64;
 483     }
 484     return res;
 485 }
 486
 487 uint64_t HELPER(neon_sub_saturate_u64)(uint64_t src1, uint64_t src2)
 488 {
 489     uint64_t res;
 490
 491     if (src1 < src2) {
 492         env->QF = 1;
 493         res = 0;
 494     } else {
 495         res = src1 - src2;
 496     }
 497     return res;
 498 }
 499
 500 /* These need to return a pair of value, so still use T0/T1.  */
 501 /* Transpose.  Argument order is rather strange to avoid special casing
 502    the tranlation code.
 503    On input T0 = rm, T1 = rd.  On output T0 = rd, T1 = rm  */
 504 void HELPER(neon_trn_u8)(void)
 505 {
 506     uint32_t rd;
 507     uint32_t rm;
 508     rd = ((T0 & 0x00ff00ff) << 8) | (T1 & 0x00ff00ff);
 509     rm = ((T1 & 0xff00ff00) >> 8) | (T0 & 0xff00ff00);
 510     T0 = rd;
 511     T1 = rm;
 512 }
 513
 514 void HELPER(neon_trn_u16)(void)
 515 {
 516     uint32_t rd;
 517     uint32_t rm;
 518     rd = (T0 << 16) | (T1 & 0xffff);
 519     rm = (T1 >> 16) | (T0 & 0xffff0000);
 520     T0 = rd;
 521     T1 = rm;
 522 }
 523
 524 /* Worker routines for zip and unzip.  */
 525 void HELPER(neon_unzip_u8)(void)
 526 {
 527     uint32_t rd;
 528     uint32_t rm;
 529     rd = (T0 & 0xff) | ((T0 >> 8) & 0xff00)
 530          | ((T1 << 16) & 0xff0000) | ((T1 << 8) & 0xff000000);
 531     rm = ((T0 >> 8) & 0xff) | ((T0 >> 16) & 0xff00)
 532          | ((T1 << 8) & 0xff0000) | (T1 & 0xff000000);
 533     T0 = rd;
 534     T1 = rm;
 535 }
 536
 537 void HELPER(neon_zip_u8)(void)
 538 {
 539     uint32_t rd;
 540     uint32_t rm;
 541     rd = (T0 & 0xff) | ((T1 << 8) & 0xff00)
 542          | ((T0 << 16) & 0xff0000) | ((T1 << 24) & 0xff000000);
 543     rm = ((T0 >> 16) & 0xff) | ((T1 >> 8) & 0xff00)
 544          | ((T0 >> 8) & 0xff0000) | (T1 & 0xff000000);
 545     T0 = rd;
 546     T1 = rm;
 547 }
 548
 549 void HELPER(neon_zip_u16)(void)
 550 {
 551     uint32_t tmp;
 552
 553     tmp = (T0 & 0xffff) | (T1 << 16);
 554     T1 = (T1 & 0xffff0000) | (T0 >> 16);
 555     T0 = tmp;
 556 }