user-exec.c

   1 /*
   2  *  User emulator execution
   3  *
   4  *  Copyright (c) 2003-2005 Fabrice Bellard
   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, see <http://www.gnu.org/licenses/>.
  18  */
  19 #include "config.h"
  20 #include "exec.h"
  21 #include "disas.h"
  22 #include "tcg.h"
  23
  24 #undef EAX
  25 #undef ECX
  26 #undef EDX
  27 #undef EBX
  28 #undef ESP
  29 #undef EBP
  30 #undef ESI
  31 #undef EDI
  32 #undef EIP
  33 #include <signal.h>
  34 #ifdef __linux__
  35 #include <sys/ucontext.h>
  36 #endif
  37
  38 //#define DEBUG_SIGNAL
  39
  40 static void exception_action(CPUState *env1)
  41 {
  42 #if defined(TARGET_I386)
  43     raise_exception_err(env1->exception_index, env1->error_code);
  44 #else
  45     cpu_loop_exit(env1);
  46 #endif
  47 }
  48
  49 /* exit the current TB from a signal handler. The host registers are
  50    restored in a state compatible with the CPU emulator
  51  */
  52 void cpu_resume_from_signal(CPUState *env1, void *puc)
  53 {
  54 #ifdef __linux__
  55     struct ucontext *uc = puc;
  56 #elif defined(__OpenBSD__)
  57     struct sigcontext *uc = puc;
  58 #endif
  59
  60     env = env1;
  61
  62     /* XXX: restore cpu registers saved in host registers */
  63
  64     if (puc) {
  65         /* XXX: use siglongjmp ? */
  66 #ifdef __linux__
  67 #ifdef __ia64
  68         sigprocmask(SIG_SETMASK, (sigset_t *)&uc->uc_sigmask, NULL);
  69 #else
  70         sigprocmask(SIG_SETMASK, &uc->uc_sigmask, NULL);
  71 #endif
  72 #elif defined(__OpenBSD__)
  73         sigprocmask(SIG_SETMASK, &uc->sc_mask, NULL);
  74 #endif
  75     }
  76     env->exception_index = -1;
  77     longjmp(env->jmp_env, 1);
  78 }
  79
  80 /* 'pc' is the host PC at which the exception was raised. 'address' is
  81    the effective address of the memory exception. 'is_write' is 1 if a
  82    write caused the exception and otherwise 0'. 'old_set' is the
  83    signal set which should be restored */
  84 static inline int handle_cpu_signal(unsigned long pc, unsigned long address,
  85                                     int is_write, sigset_t *old_set,
  86                                     void *puc)
  87 {
  88     TranslationBlock *tb;
  89     int ret;
  90
  91     if (cpu_single_env) {
  92         env = cpu_single_env; /* XXX: find a correct solution for multithread */
  93     }
  94 #if defined(DEBUG_SIGNAL)
  95     qemu_printf("qemu: SIGSEGV pc=0x%08lx address=%08lx w=%d oldset=0x%08lx\n",
  96                 pc, address, is_write, *(unsigned long *)old_set);
  97 #endif
  98     /* XXX: locking issue */
  99     if (is_write && page_unprotect(h2g(address), pc, puc)) {
 100         return 1;
 101     }
 102
 103     /* see if it is an MMU fault */
 104     ret = cpu_handle_mmu_fault(env, address, is_write, MMU_USER_IDX, 0);
 105     if (ret < 0) {
 106         return 0; /* not an MMU fault */
 107     }
 108     if (ret == 0) {
 109         return 1; /* the MMU fault was handled without causing real CPU fault */
 110     }
 111     /* now we have a real cpu fault */
 112     tb = tb_find_pc(pc);
 113     if (tb) {
 114         /* the PC is inside the translated code. It means that we have
 115            a virtual CPU fault */
 116         cpu_restore_state(tb, env, pc);
 117     }
 118
 119     /* we restore the process signal mask as the sigreturn should
 120        do it (XXX: use sigsetjmp) */
 121     sigprocmask(SIG_SETMASK, old_set, NULL);
 122     exception_action(env);
 123
 124     /* never comes here */
 125     return 1;
 126 }
 127
 128 #if defined(__i386__)
 129
 130 #if defined(__APPLE__)
 131 #include <sys/ucontext.h>
 132
 133 #define EIP_sig(context)  (*((unsigned long *)&(context)->uc_mcontext->ss.eip))
 134 #define TRAP_sig(context)    ((context)->uc_mcontext->es.trapno)
 135 #define ERROR_sig(context)   ((context)->uc_mcontext->es.err)
 136 #define MASK_sig(context)    ((context)->uc_sigmask)
 137 #elif defined(__NetBSD__)
 138 #include <ucontext.h>
 139
 140 #define EIP_sig(context)     ((context)->uc_mcontext.__gregs[_REG_EIP])
 141 #define TRAP_sig(context)    ((context)->uc_mcontext.__gregs[_REG_TRAPNO])
 142 #define ERROR_sig(context)   ((context)->uc_mcontext.__gregs[_REG_ERR])
 143 #define MASK_sig(context)    ((context)->uc_sigmask)
 144 #elif defined(__FreeBSD__) || defined(__DragonFly__)
 145 #include <ucontext.h>
 146
 147 #define EIP_sig(context)  (*((unsigned long *)&(context)->uc_mcontext.mc_eip))
 148 #define TRAP_sig(context)    ((context)->uc_mcontext.mc_trapno)
 149 #define ERROR_sig(context)   ((context)->uc_mcontext.mc_err)
 150 #define MASK_sig(context)    ((context)->uc_sigmask)
 151 #elif defined(__OpenBSD__)
 152 #define EIP_sig(context)     ((context)->sc_eip)
 153 #define TRAP_sig(context)    ((context)->sc_trapno)
 154 #define ERROR_sig(context)   ((context)->sc_err)
 155 #define MASK_sig(context)    ((context)->sc_mask)
 156 #else
 157 #define EIP_sig(context)     ((context)->uc_mcontext.gregs[REG_EIP])
 158 #define TRAP_sig(context)    ((context)->uc_mcontext.gregs[REG_TRAPNO])
 159 #define ERROR_sig(context)   ((context)->uc_mcontext.gregs[REG_ERR])
 160 #define MASK_sig(context)    ((context)->uc_sigmask)
 161 #endif
 162
 163 int cpu_signal_handler(int host_signum, void *pinfo,
 164                        void *puc)
 165 {
 166     siginfo_t *info = pinfo;
 167 #if defined(__NetBSD__) || defined(__FreeBSD__) || defined(__DragonFly__)
 168     ucontext_t *uc = puc;
 169 #elif defined(__OpenBSD__)
 170     struct sigcontext *uc = puc;
 171 #else
 172     struct ucontext *uc = puc;
 173 #endif
 174     unsigned long pc;
 175     int trapno;
 176
 177 #ifndef REG_EIP
 178 /* for glibc 2.1 */
 179 #define REG_EIP    EIP
 180 #define REG_ERR    ERR
 181 #define REG_TRAPNO TRAPNO
 182 #endif
 183     pc = EIP_sig(uc);
 184     trapno = TRAP_sig(uc);
 185     return handle_cpu_signal(pc, (unsigned long)info->si_addr,
 186                              trapno == 0xe ?
 187                              (ERROR_sig(uc) >> 1) & 1 : 0,
 188                              &MASK_sig(uc), puc);
 189 }
 190
 191 #elif defined(__x86_64__)
 192
 193 #ifdef __NetBSD__
 194 #define PC_sig(context)       _UC_MACHINE_PC(context)
 195 #define TRAP_sig(context)     ((context)->uc_mcontext.__gregs[_REG_TRAPNO])
 196 #define ERROR_sig(context)    ((context)->uc_mcontext.__gregs[_REG_ERR])
 197 #define MASK_sig(context)     ((context)->uc_sigmask)
 198 #elif defined(__OpenBSD__)
 199 #define PC_sig(context)       ((context)->sc_rip)
 200 #define TRAP_sig(context)     ((context)->sc_trapno)
 201 #define ERROR_sig(context)    ((context)->sc_err)
 202 #define MASK_sig(context)     ((context)->sc_mask)
 203 #elif defined(__FreeBSD__) || defined(__DragonFly__)
 204 #include <ucontext.h>
 205
 206 #define PC_sig(context)  (*((unsigned long *)&(context)->uc_mcontext.mc_rip))
 207 #define TRAP_sig(context)     ((context)->uc_mcontext.mc_trapno)
 208 #define ERROR_sig(context)    ((context)->uc_mcontext.mc_err)
 209 #define MASK_sig(context)     ((context)->uc_sigmask)
 210 #else
 211 #define PC_sig(context)       ((context)->uc_mcontext.gregs[REG_RIP])
 212 #define TRAP_sig(context)     ((context)->uc_mcontext.gregs[REG_TRAPNO])
 213 #define ERROR_sig(context)    ((context)->uc_mcontext.gregs[REG_ERR])
 214 #define MASK_sig(context)     ((context)->uc_sigmask)
 215 #endif
 216
 217 int cpu_signal_handler(int host_signum, void *pinfo,
 218                        void *puc)
 219 {
 220     siginfo_t *info = pinfo;
 221     unsigned long pc;
 222 #if defined(__NetBSD__) || defined(__FreeBSD__) || defined(__DragonFly__)
 223     ucontext_t *uc = puc;
 224 #elif defined(__OpenBSD__)
 225     struct sigcontext *uc = puc;
 226 #else
 227     struct ucontext *uc = puc;
 228 #endif
 229
 230     pc = PC_sig(uc);
 231     return handle_cpu_signal(pc, (unsigned long)info->si_addr,
 232                              TRAP_sig(uc) == 0xe ?
 233                              (ERROR_sig(uc) >> 1) & 1 : 0,
 234                              &MASK_sig(uc), puc);
 235 }
 236
 237 #elif defined(_ARCH_PPC)
 238
 239 /***********************************************************************
 240  * signal context platform-specific definitions
 241  * From Wine
 242  */
 243 #ifdef linux
 244 /* All Registers access - only for local access */
 245 #define REG_sig(reg_name, context)              \
 246     ((context)->uc_mcontext.regs->reg_name)
 247 /* Gpr Registers access  */
 248 #define GPR_sig(reg_num, context)              REG_sig(gpr[reg_num], context)
 249 /* Program counter */
 250 #define IAR_sig(context)                       REG_sig(nip, context)
 251 /* Machine State Register (Supervisor) */
 252 #define MSR_sig(context)                       REG_sig(msr, context)
 253 /* Count register */
 254 #define CTR_sig(context)                       REG_sig(ctr, context)
 255 /* User's integer exception register */
 256 #define XER_sig(context)                       REG_sig(xer, context)
 257 /* Link register */
 258 #define LR_sig(context)                        REG_sig(link, context)
 259 /* Condition register */
 260 #define CR_sig(context)                        REG_sig(ccr, context)
 261
 262 /* Float Registers access  */
 263 #define FLOAT_sig(reg_num, context)                                     \
 264     (((double *)((char *)((context)->uc_mcontext.regs + 48 * 4)))[reg_num])
 265 #define FPSCR_sig(context) \
 266     (*(int *)((char *)((context)->uc_mcontext.regs + (48 + 32 * 2) * 4)))
 267 /* Exception Registers access */
 268 #define DAR_sig(context)                       REG_sig(dar, context)
 269 #define DSISR_sig(context)                     REG_sig(dsisr, context)
 270 #define TRAP_sig(context)                      REG_sig(trap, context)
 271 #endif /* linux */
 272
 273 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
 274 #include <ucontext.h>
 275 #define IAR_sig(context)               ((context)->uc_mcontext.mc_srr0)
 276 #define MSR_sig(context)               ((context)->uc_mcontext.mc_srr1)
 277 #define CTR_sig(context)               ((context)->uc_mcontext.mc_ctr)
 278 #define XER_sig(context)               ((context)->uc_mcontext.mc_xer)
 279 #define LR_sig(context)                ((context)->uc_mcontext.mc_lr)
 280 #define CR_sig(context)                ((context)->uc_mcontext.mc_cr)
 281 /* Exception Registers access */
 282 #define DAR_sig(context)               ((context)->uc_mcontext.mc_dar)
 283 #define DSISR_sig(context)             ((context)->uc_mcontext.mc_dsisr)
 284 #define TRAP_sig(context)              ((context)->uc_mcontext.mc_exc)
 285 #endif /* __FreeBSD__|| __FreeBSD_kernel__ */
 286
 287 #ifdef __APPLE__
 288 #include <sys/ucontext.h>
 289 typedef struct ucontext SIGCONTEXT;
 290 /* All Registers access - only for local access */
 291 #define REG_sig(reg_name, context)              \
 292     ((context)->uc_mcontext->ss.reg_name)
 293 #define FLOATREG_sig(reg_name, context)         \
 294     ((context)->uc_mcontext->fs.reg_name)
 295 #define EXCEPREG_sig(reg_name, context)         \
 296     ((context)->uc_mcontext->es.reg_name)
 297 #define VECREG_sig(reg_name, context)           \
 298     ((context)->uc_mcontext->vs.reg_name)
 299 /* Gpr Registers access */
 300 #define GPR_sig(reg_num, context)              REG_sig(r##reg_num, context)
 301 /* Program counter */
 302 #define IAR_sig(context)                       REG_sig(srr0, context)
 303 /* Machine State Register (Supervisor) */
 304 #define MSR_sig(context)                       REG_sig(srr1, context)
 305 #define CTR_sig(context)                       REG_sig(ctr, context)
 306 /* Link register */
 307 #define XER_sig(context)                       REG_sig(xer, context)
 308 /* User's integer exception register */
 309 #define LR_sig(context)                        REG_sig(lr, context)
 310 /* Condition register */
 311 #define CR_sig(context)                        REG_sig(cr, context)
 312 /* Float Registers access */
 313 #define FLOAT_sig(reg_num, context)             \
 314     FLOATREG_sig(fpregs[reg_num], context)
 315 #define FPSCR_sig(context)                      \
 316     ((double)FLOATREG_sig(fpscr, context))
 317 /* Exception Registers access */
 318 /* Fault registers for coredump */
 319 #define DAR_sig(context)                       EXCEPREG_sig(dar, context)
 320 #define DSISR_sig(context)                     EXCEPREG_sig(dsisr, context)
 321 /* number of powerpc exception taken */
 322 #define TRAP_sig(context)                      EXCEPREG_sig(exception, context)
 323 #endif /* __APPLE__ */
 324
 325 int cpu_signal_handler(int host_signum, void *pinfo,
 326                        void *puc)
 327 {
 328     siginfo_t *info = pinfo;
 329 #if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
 330     ucontext_t *uc = puc;
 331 #else
 332     struct ucontext *uc = puc;
 333 #endif
 334     unsigned long pc;
 335     int is_write;
 336
 337     pc = IAR_sig(uc);
 338     is_write = 0;
 339 #if 0
 340     /* ppc 4xx case */
 341     if (DSISR_sig(uc) & 0x00800000) {
 342         is_write = 1;
 343     }
 344 #else
 345     if (TRAP_sig(uc) != 0x400 && (DSISR_sig(uc) & 0x02000000)) {
 346         is_write = 1;
 347     }
 348 #endif
 349     return handle_cpu_signal(pc, (unsigned long)info->si_addr,
 350                              is_write, &uc->uc_sigmask, puc);
 351 }
 352
 353 #elif defined(__alpha__)
 354
 355 int cpu_signal_handler(int host_signum, void *pinfo,
 356                            void *puc)
 357 {
 358     siginfo_t *info = pinfo;
 359     struct ucontext *uc = puc;
 360     uint32_t *pc = uc->uc_mcontext.sc_pc;
 361     uint32_t insn = *pc;
 362     int is_write = 0;
 363
 364     /* XXX: need kernel patch to get write flag faster */
 365     switch (insn >> 26) {
 366     case 0x0d: /* stw */
 367     case 0x0e: /* stb */
 368     case 0x0f: /* stq_u */
 369     case 0x24: /* stf */
 370     case 0x25: /* stg */
 371     case 0x26: /* sts */
 372     case 0x27: /* stt */
 373     case 0x2c: /* stl */
 374     case 0x2d: /* stq */
 375     case 0x2e: /* stl_c */
 376     case 0x2f: /* stq_c */
 377         is_write = 1;
 378     }
 379
 380     return handle_cpu_signal(pc, (unsigned long)info->si_addr,
 381                              is_write, &uc->uc_sigmask, puc);
 382 }
 383 #elif defined(__sparc__)
 384
 385 int cpu_signal_handler(int host_signum, void *pinfo,
 386                        void *puc)
 387 {
 388     siginfo_t *info = pinfo;
 389     int is_write;
 390     uint32_t insn;
 391 #if !defined(__arch64__) || defined(CONFIG_SOLARIS)
 392     uint32_t *regs = (uint32_t *)(info + 1);
 393     void *sigmask = (regs + 20);
 394     /* XXX: is there a standard glibc define ? */
 395     unsigned long pc = regs[1];
 396 #else
 397 #ifdef __linux__
 398     struct sigcontext *sc = puc;
 399     unsigned long pc = sc->sigc_regs.tpc;
 400     void *sigmask = (void *)sc->sigc_mask;
 401 #elif defined(__OpenBSD__)
 402     struct sigcontext *uc = puc;
 403     unsigned long pc = uc->sc_pc;
 404     void *sigmask = (void *)(long)uc->sc_mask;
 405 #endif
 406 #endif
 407
 408     /* XXX: need kernel patch to get write flag faster */
 409     is_write = 0;
 410     insn = *(uint32_t *)pc;
 411     if ((insn >> 30) == 3) {
 412         switch ((insn >> 19) & 0x3f) {
 413         case 0x05: /* stb */
 414         case 0x15: /* stba */
 415         case 0x06: /* sth */
 416         case 0x16: /* stha */
 417         case 0x04: /* st */
 418         case 0x14: /* sta */
 419         case 0x07: /* std */
 420         case 0x17: /* stda */
 421         case 0x0e: /* stx */
 422         case 0x1e: /* stxa */
 423         case 0x24: /* stf */
 424         case 0x34: /* stfa */
 425         case 0x27: /* stdf */
 426         case 0x37: /* stdfa */
 427         case 0x26: /* stqf */
 428         case 0x36: /* stqfa */
 429         case 0x25: /* stfsr */
 430         case 0x3c: /* casa */
 431         case 0x3e: /* casxa */
 432             is_write = 1;
 433             break;
 434         }
 435     }
 436     return handle_cpu_signal(pc, (unsigned long)info->si_addr,
 437                              is_write, sigmask, NULL);
 438 }
 439
 440 #elif defined(__arm__)
 441
 442 int cpu_signal_handler(int host_signum, void *pinfo,
 443                        void *puc)
 444 {
 445     siginfo_t *info = pinfo;
 446     struct ucontext *uc = puc;
 447     unsigned long pc;
 448     int is_write;
 449
 450 #if (__GLIBC__ < 2 || (__GLIBC__ == 2 && __GLIBC_MINOR__ <= 3))
 451     pc = uc->uc_mcontext.gregs[R15];
 452 #else
 453     pc = uc->uc_mcontext.arm_pc;
 454 #endif
 455     /* XXX: compute is_write */
 456     is_write = 0;
 457     return handle_cpu_signal(pc, (unsigned long)info->si_addr,
 458                              is_write,
 459                              &uc->uc_sigmask, puc);
 460 }
 461
 462 #elif defined(__mc68000)
 463
 464 int cpu_signal_handler(int host_signum, void *pinfo,
 465                        void *puc)
 466 {
 467     siginfo_t *info = pinfo;
 468     struct ucontext *uc = puc;
 469     unsigned long pc;
 470     int is_write;
 471
 472     pc = uc->uc_mcontext.gregs[16];
 473     /* XXX: compute is_write */
 474     is_write = 0;
 475     return handle_cpu_signal(pc, (unsigned long)info->si_addr,
 476                              is_write,
 477                              &uc->uc_sigmask, puc);
 478 }
 479
 480 #elif defined(__ia64)
 481
 482 #ifndef __ISR_VALID
 483   /* This ought to be in <bits/siginfo.h>... */
 484 # define __ISR_VALID    1
 485 #endif
 486
 487 int cpu_signal_handler(int host_signum, void *pinfo, void *puc)
 488 {
 489     siginfo_t *info = pinfo;
 490     struct ucontext *uc = puc;
 491     unsigned long ip;
 492     int is_write = 0;
 493
 494     ip = uc->uc_mcontext.sc_ip;
 495     switch (host_signum) {
 496     case SIGILL:
 497     case SIGFPE:
 498     case SIGSEGV:
 499     case SIGBUS:
 500     case SIGTRAP:
 501         if (info->si_code && (info->si_segvflags & __ISR_VALID)) {
 502             /* ISR.W (write-access) is bit 33:  */
 503             is_write = (info->si_isr >> 33) & 1;
 504         }
 505         break;
 506
 507     default:
 508         break;
 509     }
 510     return handle_cpu_signal(ip, (unsigned long)info->si_addr,
 511                              is_write,
 512                              (sigset_t *)&uc->uc_sigmask, puc);
 513 }
 514
 515 #elif defined(__s390__)
 516
 517 int cpu_signal_handler(int host_signum, void *pinfo,
 518                        void *puc)
 519 {
 520     siginfo_t *info = pinfo;
 521     struct ucontext *uc = puc;
 522     unsigned long pc;
 523     uint16_t *pinsn;
 524     int is_write = 0;
 525
 526     pc = uc->uc_mcontext.psw.addr;
 527
 528     /* ??? On linux, the non-rt signal handler has 4 (!) arguments instead
 529        of the normal 2 arguments.  The 3rd argument contains the "int_code"
 530        from the hardware which does in fact contain the is_write value.
 531        The rt signal handler, as far as I can tell, does not give this value
 532        at all.  Not that we could get to it from here even if it were.  */
 533     /* ??? This is not even close to complete, since it ignores all
 534        of the read-modify-write instructions.  */
 535     pinsn = (uint16_t *)pc;
 536     switch (pinsn[0] >> 8) {
 537     case 0x50: /* ST */
 538     case 0x42: /* STC */
 539     case 0x40: /* STH */
 540         is_write = 1;
 541         break;
 542     case 0xc4: /* RIL format insns */
 543         switch (pinsn[0] & 0xf) {
 544         case 0xf: /* STRL */
 545         case 0xb: /* STGRL */
 546         case 0x7: /* STHRL */
 547             is_write = 1;
 548         }
 549         break;
 550     case 0xe3: /* RXY format insns */
 551         switch (pinsn[2] & 0xff) {
 552         case 0x50: /* STY */
 553         case 0x24: /* STG */
 554         case 0x72: /* STCY */
 555         case 0x70: /* STHY */
 556         case 0x8e: /* STPQ */
 557         case 0x3f: /* STRVH */
 558         case 0x3e: /* STRV */
 559         case 0x2f: /* STRVG */
 560             is_write = 1;
 561         }
 562         break;
 563     }
 564     return handle_cpu_signal(pc, (unsigned long)info->si_addr,
 565                              is_write, &uc->uc_sigmask, puc);
 566 }
 567
 568 #elif defined(__mips__)
 569
 570 int cpu_signal_handler(int host_signum, void *pinfo,
 571                        void *puc)
 572 {
 573     siginfo_t *info = pinfo;
 574     struct ucontext *uc = puc;
 575     greg_t pc = uc->uc_mcontext.pc;
 576     int is_write;
 577
 578     /* XXX: compute is_write */
 579     is_write = 0;
 580     return handle_cpu_signal(pc, (unsigned long)info->si_addr,
 581                              is_write, &uc->uc_sigmask, puc);
 582 }
 583
 584 #elif defined(__hppa__)
 585
 586 int cpu_signal_handler(int host_signum, void *pinfo,
 587                        void *puc)
 588 {
 589     struct siginfo *info = pinfo;
 590     struct ucontext *uc = puc;
 591     unsigned long pc = uc->uc_mcontext.sc_iaoq[0];
 592     uint32_t insn = *(uint32_t *)pc;
 593     int is_write = 0;
 594
 595     /* XXX: need kernel patch to get write flag faster.  */
 596     switch (insn >> 26) {
 597     case 0x1a: /* STW */
 598     case 0x19: /* STH */
 599     case 0x18: /* STB */
 600     case 0x1b: /* STWM */
 601         is_write = 1;
 602         break;
 603
 604     case 0x09: /* CSTWX, FSTWX, FSTWS */
 605     case 0x0b: /* CSTDX, FSTDX, FSTDS */
 606         /* Distinguish from coprocessor load ... */
 607         is_write = (insn >> 9) & 1;
 608         break;
 609
 610     case 0x03:
 611         switch ((insn >> 6) & 15) {
 612         case 0xa: /* STWS */
 613         case 0x9: /* STHS */
 614         case 0x8: /* STBS */
 615         case 0xe: /* STWAS */
 616         case 0xc: /* STBYS */
 617             is_write = 1;
 618         }
 619         break;
 620     }
 621
 622     return handle_cpu_signal(pc, (unsigned long)info->si_addr,
 623                              is_write, &uc->uc_sigmask, puc);
 624 }
 625
 626 #else
 627
 628 #error host CPU specific signal handler needed
 629
 630 #endif
 631
 632 #if defined(TARGET_I386)
 633
 634 void cpu_x86_load_seg(CPUX86State *s, int seg_reg, int selector)
 635 {
 636     CPUX86State *saved_env;
 637
 638     saved_env = env;
 639     env = s;
 640     if (!(env->cr[0] & CR0_PE_MASK) || (env->eflags & VM_MASK)) {
 641         selector &= 0xffff;
 642         cpu_x86_load_seg_cache(env, seg_reg, selector,
 643                                (selector << 4), 0xffff, 0);
 644     } else {
 645         helper_load_seg(seg_reg, selector);
 646     }
 647     env = saved_env;
 648 }
 649
 650 void cpu_x86_fsave(CPUX86State *s, target_ulong ptr, int data32)
 651 {
 652     CPUX86State *saved_env;
 653
 654     saved_env = env;
 655     env = s;
 656
 657     helper_fsave(ptr, data32);
 658
 659     env = saved_env;
 660 }
 661
 662 void cpu_x86_frstor(CPUX86State *s, target_ulong ptr, int data32)
 663 {
 664     CPUX86State *saved_env;
 665
 666     saved_env = env;
 667     env = s;
 668
 669     helper_frstor(ptr, data32);
 670
 671     env = saved_env;
 672 }
 673
 674 #endif /* TARGET_I386 */