qemu/user-exec.c
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   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 "qemu/osdep.h"
  20#include "cpu.h"
  21#include "disas/disas.h"
  22#include "exec/exec-all.h"
  23#include "tcg.h"
  24#include "qemu/bitops.h"
  25#include "exec/cpu_ldst.h"
  26#include "translate-all.h"
  27
  28#undef EAX
  29#undef ECX
  30#undef EDX
  31#undef EBX
  32#undef ESP
  33#undef EBP
  34#undef ESI
  35#undef EDI
  36#undef EIP
  37#ifdef __linux__
  38#include <sys/ucontext.h>
  39#endif
  40
  41//#define DEBUG_SIGNAL
  42
  43static void exception_action(CPUState *cpu)
  44{
  45#if defined(TARGET_I386)
  46    X86CPU *x86_cpu = X86_CPU(cpu);
  47    CPUX86State *env1 = &x86_cpu->env;
  48
  49    raise_exception_err(env1, cpu->exception_index, env1->error_code);
  50#else
  51    cpu_loop_exit(cpu);
  52#endif
  53}
  54
  55/* exit the current TB from a signal handler. The host registers are
  56   restored in a state compatible with the CPU emulator
  57 */
  58void cpu_resume_from_signal(CPUState *cpu, void *puc)
  59{
  60#ifdef __linux__
  61    struct ucontext *uc = puc;
  62#elif defined(__OpenBSD__)
  63    struct sigcontext *uc = puc;
  64#endif
  65
  66    if (puc) {
  67        /* XXX: use siglongjmp ? */
  68#ifdef __linux__
  69#ifdef __ia64
  70        sigprocmask(SIG_SETMASK, (sigset_t *)&uc->uc_sigmask, NULL);
  71#else
  72        sigprocmask(SIG_SETMASK, &uc->uc_sigmask, NULL);
  73#endif
  74#elif defined(__OpenBSD__)
  75        sigprocmask(SIG_SETMASK, &uc->sc_mask, NULL);
  76#endif
  77    }
  78    cpu->exception_index = -1;
  79    siglongjmp(cpu->jmp_env, 1);
  80}
  81
  82/* 'pc' is the host PC at which the exception was raised. 'address' is
  83   the effective address of the memory exception. 'is_write' is 1 if a
  84   write caused the exception and otherwise 0'. 'old_set' is the
  85   signal set which should be restored */
  86static inline int handle_cpu_signal(uintptr_t pc, unsigned long address,
  87                                    int is_write, sigset_t *old_set,
  88                                    void *puc)
  89{
  90    CPUState *cpu;
  91    CPUClass *cc;
  92    int ret;
  93
  94#if defined(DEBUG_SIGNAL)
  95    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 && h2g_valid(address)
 100        && page_unprotect(h2g(address), pc, puc)) {
 101        return 1;
 102    }
 103
 104    /* Convert forcefully to guest address space, invalid addresses
 105       are still valid segv ones */
 106    address = h2g_nocheck(address);
 107
 108    cpu = current_cpu;
 109    cc = CPU_GET_CLASS(cpu);
 110    /* see if it is an MMU fault */
 111    g_assert(cc->handle_mmu_fault);
 112    ret = cc->handle_mmu_fault(cpu, address, is_write, MMU_USER_IDX);
 113    if (ret < 0) {
 114        return 0; /* not an MMU fault */
 115    }
 116    if (ret == 0) {
 117        return 1; /* the MMU fault was handled without causing real CPU fault */
 118    }
 119    /* now we have a real cpu fault */
 120    cpu_restore_state(cpu, pc);
 121
 122    /* we restore the process signal mask as the sigreturn should
 123       do it (XXX: use sigsetjmp) */
 124    sigprocmask(SIG_SETMASK, old_set, NULL);
 125    exception_action(cpu);
 126
 127    /* never comes here */
 128    return 1;
 129}
 130
 131#if defined(__i386__)
 132
 133#if defined(__APPLE__)
 134#include <sys/ucontext.h>
 135
 136#define EIP_sig(context)  (*((unsigned long *)&(context)->uc_mcontext->ss.eip))
 137#define TRAP_sig(context)    ((context)->uc_mcontext->es.trapno)
 138#define ERROR_sig(context)   ((context)->uc_mcontext->es.err)
 139#define MASK_sig(context)    ((context)->uc_sigmask)
 140#elif defined(__NetBSD__)
 141#include <ucontext.h>
 142
 143#define EIP_sig(context)     ((context)->uc_mcontext.__gregs[_REG_EIP])
 144#define TRAP_sig(context)    ((context)->uc_mcontext.__gregs[_REG_TRAPNO])
 145#define ERROR_sig(context)   ((context)->uc_mcontext.__gregs[_REG_ERR])
 146#define MASK_sig(context)    ((context)->uc_sigmask)
 147#elif defined(__FreeBSD__) || defined(__DragonFly__)
 148#include <ucontext.h>
 149
 150#define EIP_sig(context)  (*((unsigned long *)&(context)->uc_mcontext.mc_eip))
 151#define TRAP_sig(context)    ((context)->uc_mcontext.mc_trapno)
 152#define ERROR_sig(context)   ((context)->uc_mcontext.mc_err)
 153#define MASK_sig(context)    ((context)->uc_sigmask)
 154#elif defined(__OpenBSD__)
 155#define EIP_sig(context)     ((context)->sc_eip)
 156#define TRAP_sig(context)    ((context)->sc_trapno)
 157#define ERROR_sig(context)   ((context)->sc_err)
 158#define MASK_sig(context)    ((context)->sc_mask)
 159#else
 160#define EIP_sig(context)     ((context)->uc_mcontext.gregs[REG_EIP])
 161#define TRAP_sig(context)    ((context)->uc_mcontext.gregs[REG_TRAPNO])
 162#define ERROR_sig(context)   ((context)->uc_mcontext.gregs[REG_ERR])
 163#define MASK_sig(context)    ((context)->uc_sigmask)
 164#endif
 165
 166int cpu_signal_handler(int host_signum, void *pinfo,
 167                       void *puc)
 168{
 169    siginfo_t *info = pinfo;
 170#if defined(__NetBSD__) || defined(__FreeBSD__) || defined(__DragonFly__)
 171    ucontext_t *uc = puc;
 172#elif defined(__OpenBSD__)
 173    struct sigcontext *uc = puc;
 174#else
 175    struct ucontext *uc = puc;
 176#endif
 177    unsigned long pc;
 178    int trapno;
 179
 180#ifndef REG_EIP
 181/* for glibc 2.1 */
 182#define REG_EIP    EIP
 183#define REG_ERR    ERR
 184#define REG_TRAPNO TRAPNO
 185#endif
 186    pc = EIP_sig(uc);
 187    trapno = TRAP_sig(uc);
 188    return handle_cpu_signal(pc, (unsigned long)info->si_addr,
 189                             trapno == 0xe ?
 190                             (ERROR_sig(uc) >> 1) & 1 : 0,
 191                             &MASK_sig(uc), puc);
 192}
 193
 194#elif defined(__x86_64__)
 195
 196#ifdef __NetBSD__
 197#define PC_sig(context)       _UC_MACHINE_PC(context)
 198#define TRAP_sig(context)     ((context)->uc_mcontext.__gregs[_REG_TRAPNO])
 199#define ERROR_sig(context)    ((context)->uc_mcontext.__gregs[_REG_ERR])
 200#define MASK_sig(context)     ((context)->uc_sigmask)
 201#elif defined(__OpenBSD__)
 202#define PC_sig(context)       ((context)->sc_rip)
 203#define TRAP_sig(context)     ((context)->sc_trapno)
 204#define ERROR_sig(context)    ((context)->sc_err)
 205#define MASK_sig(context)     ((context)->sc_mask)
 206#elif defined(__FreeBSD__) || defined(__DragonFly__)
 207#include <ucontext.h>
 208
 209#define PC_sig(context)  (*((unsigned long *)&(context)->uc_mcontext.mc_rip))
 210#define TRAP_sig(context)     ((context)->uc_mcontext.mc_trapno)
 211#define ERROR_sig(context)    ((context)->uc_mcontext.mc_err)
 212#define MASK_sig(context)     ((context)->uc_sigmask)
 213#else
 214#define PC_sig(context)       ((context)->uc_mcontext.gregs[REG_RIP])
 215#define TRAP_sig(context)     ((context)->uc_mcontext.gregs[REG_TRAPNO])
 216#define ERROR_sig(context)    ((context)->uc_mcontext.gregs[REG_ERR])
 217#define MASK_sig(context)     ((context)->uc_sigmask)
 218#endif
 219
 220int cpu_signal_handler(int host_signum, void *pinfo,
 221                       void *puc)
 222{
 223    siginfo_t *info = pinfo;
 224    unsigned long pc;
 225#if defined(__NetBSD__) || defined(__FreeBSD__) || defined(__DragonFly__)
 226    ucontext_t *uc = puc;
 227#elif defined(__OpenBSD__)
 228    struct sigcontext *uc = puc;
 229#else
 230    struct ucontext *uc = puc;
 231#endif
 232
 233    pc = PC_sig(uc);
 234    return handle_cpu_signal(pc, (unsigned long)info->si_addr,
 235                             TRAP_sig(uc) == 0xe ?
 236                             (ERROR_sig(uc) >> 1) & 1 : 0,
 237                             &MASK_sig(uc), puc);
 238}
 239
 240#elif defined(_ARCH_PPC)
 241
 242/***********************************************************************
 243 * signal context platform-specific definitions
 244 * From Wine
 245 */
 246#ifdef linux
 247/* All Registers access - only for local access */
 248#define REG_sig(reg_name, context)              \
 249    ((context)->uc_mcontext.regs->reg_name)
 250/* Gpr Registers access  */
 251#define GPR_sig(reg_num, context)              REG_sig(gpr[reg_num], context)
 252/* Program counter */
 253#define IAR_sig(context)                       REG_sig(nip, context)
 254/* Machine State Register (Supervisor) */
 255#define MSR_sig(context)                       REG_sig(msr, context)
 256/* Count register */
 257#define CTR_sig(context)                       REG_sig(ctr, context)
 258/* User's integer exception register */
 259#define XER_sig(context)                       REG_sig(xer, context)
 260/* Link register */
 261#define LR_sig(context)                        REG_sig(link, context)
 262/* Condition register */
 263#define CR_sig(context)                        REG_sig(ccr, context)
 264
 265/* Float Registers access  */
 266#define FLOAT_sig(reg_num, context)                                     \
 267    (((double *)((char *)((context)->uc_mcontext.regs + 48 * 4)))[reg_num])
 268#define FPSCR_sig(context) \
 269    (*(int *)((char *)((context)->uc_mcontext.regs + (48 + 32 * 2) * 4)))
 270/* Exception Registers access */
 271#define DAR_sig(context)                       REG_sig(dar, context)
 272#define DSISR_sig(context)                     REG_sig(dsisr, context)
 273#define TRAP_sig(context)                      REG_sig(trap, context)
 274#endif /* linux */
 275
 276#if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
 277#include <ucontext.h>
 278#define IAR_sig(context)               ((context)->uc_mcontext.mc_srr0)
 279#define MSR_sig(context)               ((context)->uc_mcontext.mc_srr1)
 280#define CTR_sig(context)               ((context)->uc_mcontext.mc_ctr)
 281#define XER_sig(context)               ((context)->uc_mcontext.mc_xer)
 282#define LR_sig(context)                ((context)->uc_mcontext.mc_lr)
 283#define CR_sig(context)                ((context)->uc_mcontext.mc_cr)
 284/* Exception Registers access */
 285#define DAR_sig(context)               ((context)->uc_mcontext.mc_dar)
 286#define DSISR_sig(context)             ((context)->uc_mcontext.mc_dsisr)
 287#define TRAP_sig(context)              ((context)->uc_mcontext.mc_exc)
 288#endif /* __FreeBSD__|| __FreeBSD_kernel__ */
 289
 290#ifdef __APPLE__
 291#include <sys/ucontext.h>
 292typedef struct ucontext SIGCONTEXT;
 293/* All Registers access - only for local access */
 294#define REG_sig(reg_name, context)              \
 295    ((context)->uc_mcontext->ss.reg_name)
 296#define FLOATREG_sig(reg_name, context)         \
 297    ((context)->uc_mcontext->fs.reg_name)
 298#define EXCEPREG_sig(reg_name, context)         \
 299    ((context)->uc_mcontext->es.reg_name)
 300#define VECREG_sig(reg_name, context)           \
 301    ((context)->uc_mcontext->vs.reg_name)
 302/* Gpr Registers access */
 303#define GPR_sig(reg_num, context)              REG_sig(r##reg_num, context)
 304/* Program counter */
 305#define IAR_sig(context)                       REG_sig(srr0, context)
 306/* Machine State Register (Supervisor) */
 307#define MSR_sig(context)                       REG_sig(srr1, context)
 308#define CTR_sig(context)                       REG_sig(ctr, context)
 309/* Link register */
 310#define XER_sig(context)                       REG_sig(xer, context)
 311/* User's integer exception register */
 312#define LR_sig(context)                        REG_sig(lr, context)
 313/* Condition register */
 314#define CR_sig(context)                        REG_sig(cr, context)
 315/* Float Registers access */
 316#define FLOAT_sig(reg_num, context)             \
 317    FLOATREG_sig(fpregs[reg_num], context)
 318#define FPSCR_sig(context)                      \
 319    ((double)FLOATREG_sig(fpscr, context))
 320/* Exception Registers access */
 321/* Fault registers for coredump */
 322#define DAR_sig(context)                       EXCEPREG_sig(dar, context)
 323#define DSISR_sig(context)                     EXCEPREG_sig(dsisr, context)
 324/* number of powerpc exception taken */
 325#define TRAP_sig(context)                      EXCEPREG_sig(exception, context)
 326#endif /* __APPLE__ */
 327
 328int cpu_signal_handler(int host_signum, void *pinfo,
 329                       void *puc)
 330{
 331    siginfo_t *info = pinfo;
 332#if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
 333    ucontext_t *uc = puc;
 334#else
 335    struct ucontext *uc = puc;
 336#endif
 337    unsigned long pc;
 338    int is_write;
 339
 340    pc = IAR_sig(uc);
 341    is_write = 0;
 342#if 0
 343    /* ppc 4xx case */
 344    if (DSISR_sig(uc) & 0x00800000) {
 345        is_write = 1;
 346    }
 347#else
 348    if (TRAP_sig(uc) != 0x400 && (DSISR_sig(uc) & 0x02000000)) {
 349        is_write = 1;
 350    }
 351#endif
 352    return handle_cpu_signal(pc, (unsigned long)info->si_addr,
 353                             is_write, &uc->uc_sigmask, puc);
 354}
 355
 356#elif defined(__alpha__)
 357
 358int cpu_signal_handler(int host_signum, void *pinfo,
 359                           void *puc)
 360{
 361    siginfo_t *info = pinfo;
 362    struct ucontext *uc = puc;
 363    uint32_t *pc = uc->uc_mcontext.sc_pc;
 364    uint32_t insn = *pc;
 365    int is_write = 0;
 366
 367    /* XXX: need kernel patch to get write flag faster */
 368    switch (insn >> 26) {
 369    case 0x0d: /* stw */
 370    case 0x0e: /* stb */
 371    case 0x0f: /* stq_u */
 372    case 0x24: /* stf */
 373    case 0x25: /* stg */
 374    case 0x26: /* sts */
 375    case 0x27: /* stt */
 376    case 0x2c: /* stl */
 377    case 0x2d: /* stq */
 378    case 0x2e: /* stl_c */
 379    case 0x2f: /* stq_c */
 380        is_write = 1;
 381    }
 382
 383    return handle_cpu_signal(pc, (unsigned long)info->si_addr,
 384                             is_write, &uc->uc_sigmask, puc);
 385}
 386#elif defined(__sparc__)
 387
 388int cpu_signal_handler(int host_signum, void *pinfo,
 389                       void *puc)
 390{
 391    siginfo_t *info = pinfo;
 392    int is_write;
 393    uint32_t insn;
 394#if !defined(__arch64__) || defined(CONFIG_SOLARIS)
 395    uint32_t *regs = (uint32_t *)(info + 1);
 396    void *sigmask = (regs + 20);
 397    /* XXX: is there a standard glibc define ? */
 398    unsigned long pc = regs[1];
 399#else
 400#ifdef __linux__
 401    struct sigcontext *sc = puc;
 402    unsigned long pc = sc->sigc_regs.tpc;
 403    void *sigmask = (void *)sc->sigc_mask;
 404#elif defined(__OpenBSD__)
 405    struct sigcontext *uc = puc;
 406    unsigned long pc = uc->sc_pc;
 407    void *sigmask = (void *)(long)uc->sc_mask;
 408#elif defined(__NetBSD__)
 409    ucontext_t *uc = puc;
 410    unsigned long pc = _UC_MACHINE_PC(uc);
 411    void *sigmask = (void *)&uc->uc_sigmask;
 412#endif
 413#endif
 414
 415    /* XXX: need kernel patch to get write flag faster */
 416    is_write = 0;
 417    insn = *(uint32_t *)pc;
 418    if ((insn >> 30) == 3) {
 419        switch ((insn >> 19) & 0x3f) {
 420        case 0x05: /* stb */
 421        case 0x15: /* stba */
 422        case 0x06: /* sth */
 423        case 0x16: /* stha */
 424        case 0x04: /* st */
 425        case 0x14: /* sta */
 426        case 0x07: /* std */
 427        case 0x17: /* stda */
 428        case 0x0e: /* stx */
 429        case 0x1e: /* stxa */
 430        case 0x24: /* stf */
 431        case 0x34: /* stfa */
 432        case 0x27: /* stdf */
 433        case 0x37: /* stdfa */
 434        case 0x26: /* stqf */
 435        case 0x36: /* stqfa */
 436        case 0x25: /* stfsr */
 437        case 0x3c: /* casa */
 438        case 0x3e: /* casxa */
 439            is_write = 1;
 440            break;
 441        }
 442    }
 443    return handle_cpu_signal(pc, (unsigned long)info->si_addr,
 444                             is_write, sigmask, NULL);
 445}
 446
 447#elif defined(__arm__)
 448
 449#if defined(__NetBSD__)
 450#include <ucontext.h>
 451#endif
 452
 453int cpu_signal_handler(int host_signum, void *pinfo,
 454                       void *puc)
 455{
 456    siginfo_t *info = pinfo;
 457#if defined(__NetBSD__)
 458    ucontext_t *uc = puc;
 459#else
 460    struct ucontext *uc = puc;
 461#endif
 462    unsigned long pc;
 463    int is_write;
 464
 465#if defined(__NetBSD__)
 466    pc = uc->uc_mcontext.__gregs[_REG_R15];
 467#elif defined(__GLIBC__) && (__GLIBC__ < 2 || (__GLIBC__ == 2 && __GLIBC_MINOR__ <= 3))
 468    pc = uc->uc_mcontext.gregs[R15];
 469#else
 470    pc = uc->uc_mcontext.arm_pc;
 471#endif
 472
 473    /* error_code is the FSR value, in which bit 11 is WnR (assuming a v6 or
 474     * later processor; on v5 we will always report this as a read).
 475     */
 476    is_write = extract32(uc->uc_mcontext.error_code, 11, 1);
 477    return handle_cpu_signal(pc, (unsigned long)info->si_addr,
 478                             is_write,
 479                             &uc->uc_sigmask, puc);
 480}
 481
 482#elif defined(__aarch64__)
 483
 484int cpu_signal_handler(int host_signum, void *pinfo, void *puc)
 485{
 486    siginfo_t *info = pinfo;
 487    struct ucontext *uc = puc;
 488    uintptr_t pc = uc->uc_mcontext.pc;
 489    uint32_t insn = *(uint32_t *)pc;
 490    bool is_write;
 491
 492    /* XXX: need kernel patch to get write flag faster.  */
 493    is_write = (   (insn & 0xbfff0000) == 0x0c000000   /* C3.3.1 */
 494                || (insn & 0xbfe00000) == 0x0c800000   /* C3.3.2 */
 495                || (insn & 0xbfdf0000) == 0x0d000000   /* C3.3.3 */
 496                || (insn & 0xbfc00000) == 0x0d800000   /* C3.3.4 */
 497                || (insn & 0x3f400000) == 0x08000000   /* C3.3.6 */
 498                || (insn & 0x3bc00000) == 0x39000000   /* C3.3.13 */
 499                || (insn & 0x3fc00000) == 0x3d800000   /* ... 128bit */
 500                /* Ingore bits 10, 11 & 21, controlling indexing.  */
 501                || (insn & 0x3bc00000) == 0x38000000   /* C3.3.8-12 */
 502                || (insn & 0x3fe00000) == 0x3c800000   /* ... 128bit */
 503                /* Ignore bits 23 & 24, controlling indexing.  */
 504                || (insn & 0x3a400000) == 0x28000000); /* C3.3.7,14-16 */
 505
 506    return handle_cpu_signal(pc, (uintptr_t)info->si_addr,
 507                             is_write, &uc->uc_sigmask, puc);
 508}
 509
 510#elif defined(__mc68000)
 511
 512int cpu_signal_handler(int host_signum, void *pinfo,
 513                       void *puc)
 514{
 515    siginfo_t *info = pinfo;
 516    struct ucontext *uc = puc;
 517    unsigned long pc;
 518    int is_write;
 519
 520    pc = uc->uc_mcontext.gregs[16];
 521    /* XXX: compute is_write */
 522    is_write = 0;
 523    return handle_cpu_signal(pc, (unsigned long)info->si_addr,
 524                             is_write,
 525                             &uc->uc_sigmask, puc);
 526}
 527
 528#elif defined(__ia64)
 529
 530#ifndef __ISR_VALID
 531  /* This ought to be in <bits/siginfo.h>... */
 532# define __ISR_VALID    1
 533#endif
 534
 535int cpu_signal_handler(int host_signum, void *pinfo, void *puc)
 536{
 537    siginfo_t *info = pinfo;
 538    struct ucontext *uc = puc;
 539    unsigned long ip;
 540    int is_write = 0;
 541
 542    ip = uc->uc_mcontext.sc_ip;
 543    switch (host_signum) {
 544    case SIGILL:
 545    case SIGFPE:
 546    case SIGSEGV:
 547    case SIGBUS:
 548    case SIGTRAP:
 549        if (info->si_code && (info->si_segvflags & __ISR_VALID)) {
 550            /* ISR.W (write-access) is bit 33:  */
 551            is_write = (info->si_isr >> 33) & 1;
 552        }
 553        break;
 554
 555    default:
 556        break;
 557    }
 558    return handle_cpu_signal(ip, (unsigned long)info->si_addr,
 559                             is_write,
 560                             (sigset_t *)&uc->uc_sigmask, puc);
 561}
 562
 563#elif defined(__s390__)
 564
 565int cpu_signal_handler(int host_signum, void *pinfo,
 566                       void *puc)
 567{
 568    siginfo_t *info = pinfo;
 569    struct ucontext *uc = puc;
 570    unsigned long pc;
 571    uint16_t *pinsn;
 572    int is_write = 0;
 573
 574    pc = uc->uc_mcontext.psw.addr;
 575
 576    /* ??? On linux, the non-rt signal handler has 4 (!) arguments instead
 577       of the normal 2 arguments.  The 3rd argument contains the "int_code"
 578       from the hardware which does in fact contain the is_write value.
 579       The rt signal handler, as far as I can tell, does not give this value
 580       at all.  Not that we could get to it from here even if it were.  */
 581    /* ??? This is not even close to complete, since it ignores all
 582       of the read-modify-write instructions.  */
 583    pinsn = (uint16_t *)pc;
 584    switch (pinsn[0] >> 8) {
 585    case 0x50: /* ST */
 586    case 0x42: /* STC */
 587    case 0x40: /* STH */
 588        is_write = 1;
 589        break;
 590    case 0xc4: /* RIL format insns */
 591        switch (pinsn[0] & 0xf) {
 592        case 0xf: /* STRL */
 593        case 0xb: /* STGRL */
 594        case 0x7: /* STHRL */
 595            is_write = 1;
 596        }
 597        break;
 598    case 0xe3: /* RXY format insns */
 599        switch (pinsn[2] & 0xff) {
 600        case 0x50: /* STY */
 601        case 0x24: /* STG */
 602        case 0x72: /* STCY */
 603        case 0x70: /* STHY */
 604        case 0x8e: /* STPQ */
 605        case 0x3f: /* STRVH */
 606        case 0x3e: /* STRV */
 607        case 0x2f: /* STRVG */
 608            is_write = 1;
 609        }
 610        break;
 611    }
 612    return handle_cpu_signal(pc, (unsigned long)info->si_addr,
 613                             is_write, &uc->uc_sigmask, puc);
 614}
 615
 616#elif defined(__mips__)
 617
 618int cpu_signal_handler(int host_signum, void *pinfo,
 619                       void *puc)
 620{
 621    siginfo_t *info = pinfo;
 622    struct ucontext *uc = puc;
 623    greg_t pc = uc->uc_mcontext.pc;
 624    int is_write;
 625
 626    /* XXX: compute is_write */
 627    is_write = 0;
 628    return handle_cpu_signal(pc, (unsigned long)info->si_addr,
 629                             is_write, &uc->uc_sigmask, puc);
 630}
 631
 632#elif defined(__hppa__)
 633
 634int cpu_signal_handler(int host_signum, void *pinfo,
 635                       void *puc)
 636{
 637    siginfo_t *info = pinfo;
 638    struct ucontext *uc = puc;
 639    unsigned long pc = uc->uc_mcontext.sc_iaoq[0];
 640    uint32_t insn = *(uint32_t *)pc;
 641    int is_write = 0;
 642
 643    /* XXX: need kernel patch to get write flag faster.  */
 644    switch (insn >> 26) {
 645    case 0x1a: /* STW */
 646    case 0x19: /* STH */
 647    case 0x18: /* STB */
 648    case 0x1b: /* STWM */
 649        is_write = 1;
 650        break;
 651
 652    case 0x09: /* CSTWX, FSTWX, FSTWS */
 653    case 0x0b: /* CSTDX, FSTDX, FSTDS */
 654        /* Distinguish from coprocessor load ... */
 655        is_write = (insn >> 9) & 1;
 656        break;
 657
 658    case 0x03:
 659        switch ((insn >> 6) & 15) {
 660        case 0xa: /* STWS */
 661        case 0x9: /* STHS */
 662        case 0x8: /* STBS */
 663        case 0xe: /* STWAS */
 664        case 0xc: /* STBYS */
 665            is_write = 1;
 666        }
 667        break;
 668    }
 669
 670    return handle_cpu_signal(pc, (unsigned long)info->si_addr,
 671                             is_write, &uc->uc_sigmask, puc);
 672}
 673
 674#else
 675
 676#error host CPU specific signal handler needed
 677
 678#endif
 679