main.c

qemu性能直逼VMware的仿真器QEMU 的模擬速度約為實機的 25％；約為 Bochs 的 60 倍。Plex86、User-Mode-Linux、VMware 和 Virtual PC 則比

        switch (trapnr) {
        case 0x160:
            ret = do_syscall(env, 
                             env->gregs[3], 
                             env->gregs[4], 
                             env->gregs[5], 
                             env->gregs[6], 
                             env->gregs[7], 
                             env->gregs[0], 
                             0);
            env->gregs[0] = ret;
            env->pc += 2;
            break;
        case EXCP_DEBUG:
            {
                int sig;

                sig = gdb_handlesig (env, TARGET_SIGTRAP);
                if (sig)
                  {
                    info.si_signo = sig;
                    info.si_errno = 0;
                    info.si_code = TARGET_TRAP_BRKPT;
                    queue_signal(info.si_signo, &info);
                  }
            }
            break;
        default:
            printf ("Unhandled trap: 0x%x\n", trapnr);
            cpu_dump_state(env, stderr, fprintf, 0);
            exit (1);
        }
        process_pending_signals (env);
    }
}
#endif

#ifdef TARGET_M68K

void cpu_loop(CPUM68KState *env)
{
    int trapnr;
    unsigned int n;
    target_siginfo_t info;
    TaskState *ts = env->opaque;
    
    for(;;) {
        trapnr = cpu_m68k_exec(env);
        switch(trapnr) {
        case EXCP_ILLEGAL:
            {
                if (ts->sim_syscalls) {
                    uint16_t nr;
                    nr = lduw(env->pc + 2);
                    env->pc += 4;
                    do_m68k_simcall(env, nr);
                } else {
                    goto do_sigill;
                }
            }
            break;
        case EXCP_HALTED:
            /* Semihosing syscall.  */
            env->pc += 2;
            do_m68k_semihosting(env, env->dregs[0]);
            break;
        case EXCP_LINEA:
        case EXCP_LINEF:
        case EXCP_UNSUPPORTED:
        do_sigill:
            info.si_signo = SIGILL;
            info.si_errno = 0;
            info.si_code = TARGET_ILL_ILLOPN;
            info._sifields._sigfault._addr = env->pc;
            queue_signal(info.si_signo, &info);
            break;
        case EXCP_TRAP0:
            {
                ts->sim_syscalls = 0;
                n = env->dregs[0];
                env->pc += 2;
                env->dregs[0] = do_syscall(env, 
                                          n, 
                                          env->dregs[1],
                                          env->dregs[2],
                                          env->dregs[3],
                                          env->dregs[4],
                                          env->dregs[5],
                                          env->dregs[6]);
            }
            break;
        case EXCP_INTERRUPT:
            /* just indicate that signals should be handled asap */
            break;
        case EXCP_ACCESS:
            {
                info.si_signo = SIGSEGV;
                info.si_errno = 0;
                /* XXX: check env->error_code */
                info.si_code = TARGET_SEGV_MAPERR;
                info._sifields._sigfault._addr = env->mmu.ar;
                queue_signal(info.si_signo, &info);
            }
            break;
        case EXCP_DEBUG:
            {
                int sig;

                sig = gdb_handlesig (env, TARGET_SIGTRAP);
                if (sig)
                  {
                    info.si_signo = sig;
                    info.si_errno = 0;
                    info.si_code = TARGET_TRAP_BRKPT;
                    queue_signal(info.si_signo, &info);
                  }
            }
            break;
        default:
            fprintf(stderr, "qemu: unhandled CPU exception 0x%x - aborting\n", 
                    trapnr);
            cpu_dump_state(env, stderr, fprintf, 0);
            abort();
        }
        process_pending_signals(env);
    }
}
#endif /* TARGET_M68K */

void usage(void)
{
    printf("qemu-" TARGET_ARCH " version " QEMU_VERSION ", Copyright (c) 2003-2007 Fabrice Bellard\n"
           "usage: qemu-" TARGET_ARCH " [-h] [-g] [-d opts] [-L path] [-s size] program [arguments...]\n"
           "Linux CPU emulator (compiled for %s emulation)\n"
           "\n"
           "-h           print this help\n"
           "-g port      wait gdb connection to port\n"
           "-L path      set the elf interpreter prefix (default=%s)\n"
           "-s size      set the stack size in bytes (default=%ld)\n"
           "\n"
           "debug options:\n"
#ifdef USE_CODE_COPY
           "-no-code-copy   disable code copy acceleration\n"
#endif
           "-d options   activate log (logfile=%s)\n"
           "-p pagesize  set the host page size to 'pagesize'\n",
           TARGET_ARCH,
           interp_prefix, 
           x86_stack_size,
           DEBUG_LOGFILE);
    _exit(1);
}

/* XXX: currently only used for async signals (see signal.c) */
CPUState *global_env;

/* used to free thread contexts */
TaskState *first_task_state;

int main(int argc, char **argv)
{
    const char *filename;
    struct target_pt_regs regs1, *regs = &regs1;
    struct image_info info1, *info = &info1;
    TaskState ts1, *ts = &ts1;
    CPUState *env;
    int optind;
    const char *r;
    int gdbstub_port = 0;
    
    if (argc <= 1)
        usage();

    /* init debug */
    cpu_set_log_filename(DEBUG_LOGFILE);

    optind = 1;
    for(;;) {
        if (optind >= argc)
            break;
        r = argv[optind];
        if (r[0] != '-')
            break;
        optind++;
        r++;
        if (!strcmp(r, "-")) {
            break;
        } else if (!strcmp(r, "d")) {
            int mask;
            CPULogItem *item;

	    if (optind >= argc)
		break;
            
	    r = argv[optind++];
            mask = cpu_str_to_log_mask(r);
            if (!mask) {
                printf("Log items (comma separated):\n");
                for(item = cpu_log_items; item->mask != 0; item++) {
                    printf("%-10s %s\n", item->name, item->help);
                }
                exit(1);
            }
            cpu_set_log(mask);
        } else if (!strcmp(r, "s")) {
            r = argv[optind++];
            x86_stack_size = strtol(r, (char **)&r, 0);
            if (x86_stack_size <= 0)
                usage();
            if (*r == 'M')
                x86_stack_size *= 1024 * 1024;
            else if (*r == 'k' || *r == 'K')
                x86_stack_size *= 1024;
        } else if (!strcmp(r, "L")) {
            interp_prefix = argv[optind++];
        } else if (!strcmp(r, "p")) {
            qemu_host_page_size = atoi(argv[optind++]);
            if (qemu_host_page_size == 0 ||
                (qemu_host_page_size & (qemu_host_page_size - 1)) != 0) {
                fprintf(stderr, "page size must be a power of two\n");
                exit(1);
            }
        } else if (!strcmp(r, "g")) {
            gdbstub_port = atoi(argv[optind++]);
	} else if (!strcmp(r, "r")) {
	    qemu_uname_release = argv[optind++];
        } else 
#ifdef USE_CODE_COPY
        if (!strcmp(r, "no-code-copy")) {
            code_copy_enabled = 0;
        } else 
#endif
        {
            usage();
        }
    }
    if (optind >= argc)
        usage();
    filename = argv[optind];

    /* Zero out regs */
    memset(regs, 0, sizeof(struct target_pt_regs));

    /* Zero out image_info */
    memset(info, 0, sizeof(struct image_info));

    /* Scan interp_prefix dir for replacement files. */
    init_paths(interp_prefix);

    /* NOTE: we need to init the CPU at this stage to get
       qemu_host_page_size */
    env = cpu_init();
    global_env = env;
    
    if (loader_exec(filename, argv+optind, environ, regs, info) != 0) {
	printf("Error loading %s\n", filename);
	_exit(1);
    }
    
    if (loglevel) {
        page_dump(logfile);
    
        fprintf(logfile, "start_brk   0x%08lx\n" , info->start_brk);
        fprintf(logfile, "end_code    0x%08lx\n" , info->end_code);
        fprintf(logfile, "start_code  0x%08lx\n" , info->start_code);
        fprintf(logfile, "start_data  0x%08lx\n" , info->start_data);
        fprintf(logfile, "end_data    0x%08lx\n" , info->end_data);
        fprintf(logfile, "start_stack 0x%08lx\n" , info->start_stack);
        fprintf(logfile, "brk         0x%08lx\n" , info->brk);
        fprintf(logfile, "entry       0x%08lx\n" , info->entry);
    }

    target_set_brk(info->brk);
    syscall_init();
    signal_init();

    /* build Task State */
    memset(ts, 0, sizeof(TaskState));
    env->opaque = ts;
    ts->used = 1;
    ts->info = info;
    env->user_mode_only = 1;
    
#if defined(TARGET_I386)
    cpu_x86_set_cpl(env, 3);

    env->cr[0] = CR0_PG_MASK | CR0_WP_MASK | CR0_PE_MASK;
    env->hflags |= HF_PE_MASK;
    if (env->cpuid_features & CPUID_SSE) {
        env->cr[4] |= CR4_OSFXSR_MASK;
        env->hflags |= HF_OSFXSR_MASK;
    }

    /* flags setup : we activate the IRQs by default as in user mode */
    env->eflags |= IF_MASK;
    
    /* linux register setup */
    env->regs[R_EAX] = regs->eax;
    env->regs[R_EBX] = regs->ebx;
    env->regs[R_ECX] = regs->ecx;
    env->regs[R_EDX] = regs->edx;
    env->regs[R_ESI] = regs->esi;
    env->regs[R_EDI] = regs->edi;
    env->regs[R_EBP] = regs->ebp;
    env->regs[R_ESP] = regs->esp;
    env->eip = regs->eip;

    /* linux interrupt setup */
    env->idt.base = h2g(idt_table);
    env->idt.limit = sizeof(idt_table) - 1;
    set_idt(0, 0);
    set_idt(1, 0);
    set_idt(2, 0);
    set_idt(3, 3);
    set_idt(4, 3);
    set_idt(5, 3);
    set_idt(6, 0);
    set_idt(7, 0);
    set_idt(8, 0);
    set_idt(9, 0);
    set_idt(10, 0);
    set_idt(11, 0);
    set_idt(12, 0);
    set_idt(13, 0);
    set_idt(14, 0);
    set_idt(15, 0);
    set_idt(16, 0);
    set_idt(17, 0);
    set_idt(18, 0);
    set_idt(19, 0);
    set_idt(0x80, 3);

    /* linux segment setup */
    env->gdt.base = h2g(gdt_table);
    env->gdt.limit = sizeof(gdt_table) - 1;
    write_dt(&gdt_table[__USER_CS >> 3], 0, 0xfffff,
             DESC_G_MASK | DESC_B_MASK | DESC_P_MASK | DESC_S_MASK | 
             (3 << DESC_DPL_SHIFT) | (0xa << DESC_TYPE_SHIFT));
    write_dt(&gdt_table[__USER_DS >> 3], 0, 0xfffff,
             DESC_G_MASK | DESC_B_MASK | DESC_P_MASK | DESC_S_MASK | 
             (3 << DESC_DPL_SHIFT) | (0x2 << DESC_TYPE_SHIFT));
    cpu_x86_load_seg(env, R_CS, __USER_CS);
    cpu_x86_load_seg(env, R_DS, __USER_DS);
    cpu_x86_load_seg(env, R_ES, __USER_DS);
    cpu_x86_load_seg(env, R_SS, __USER_DS);
    cpu_x86_load_seg(env, R_FS, __USER_DS);
    cpu_x86_load_seg(env, R_GS, __USER_DS);

#elif defined(TARGET_ARM)
    {
        int i;
        cpu_arm_set_model(env, ARM_CPUID_ARM1026);
        cpsr_write(env, regs->uregs[16], 0xffffffff);
        for(i = 0; i < 16; i++) {
            env->regs[i] = regs->uregs[i];
        }
        ts->stack_base = info->start_stack;
        ts->heap_base = info->brk;
        /* This will be filled in on the first SYS_HEAPINFO call.  */
        ts->heap_limit = 0;
    }
#elif defined(TARGET_SPARC)
    {
        int i;
	env->pc = regs->pc;
	env->npc = regs->npc;
        env->y = regs->y;
        for(i = 0; i < 8; i++)
            env->gregs[i] = regs->u_regs[i];
        for(i = 0; i < 8; i++)
            env->regwptr[i] = regs->u_regs[i + 8];
    }
#elif defined(TARGET_PPC)
    {
        ppc_def_t *def;
        int i;

        /* Choose and initialise CPU */
        /* XXX: CPU model (or PVR) should be provided on command line */
        //        ppc_find_by_name("750gx", &def);
        //        ppc_find_by_name("750fx", &def);
        //        ppc_find_by_name("750p", &def);
        ppc_find_by_name("750", &def);
        //        ppc_find_by_name("G3", &def);
        //        ppc_find_by_name("604r", &def);
        //        ppc_find_by_name("604e", &def);
        //        ppc_find_by_name("604", &def);
        if (def == NULL) {
            cpu_abort(env,
                      "Unable to find PowerPC CPU definition\n");
        }
        cpu_ppc_register(env, def);

        for (i = 0; i < 32; i++) {
            if (i != 12 && i != 6 && i != 13)
                env->msr[i] = (regs->msr >> i) & 1;
        }
        env->nip = regs->nip;
        for(i = 0; i < 32; i++) {
            env->gpr[i] = regs->gpr[i];
        }
    }
#elif defined(TARGET_M68K)
    {
        m68k_def_t *def;
        def = m68k_find_by_name("cfv4e");
        if (def == NULL) {
            cpu_abort(cpu_single_env,
                      "Unable to find m68k CPU definition\n");
        }
        cpu_m68k_register(cpu_single_env, def);
        env->pc = regs->pc;
        env->dregs[0] = regs->d0;
        env->dregs[1] = regs->d1;
        env->dregs[2] = regs->d2;
        env->dregs[3] = regs->d3;
        env->dregs[4] = regs->d4;
        env->dregs[5] = regs->d5;
        env->dregs[6] = regs->d6;
        env->dregs[7] = regs->d7;
        env->aregs[0] = regs->a0;
        env->aregs[1] = regs->a1;
        env->aregs[2] = regs->a2;
        env->aregs[3] = regs->a3;
        env->aregs[4] = regs->a4;
        env->aregs[5] = regs->a5;
        env->aregs[6] = regs->a6;
        env->aregs[7] = regs->usp;
        env->sr = regs->sr;
        ts->sim_syscalls = 1;
    }
#elif defined(TARGET_MIPS)
    {
        int i;

        for(i = 0; i < 32; i++) {
            env->gpr[i] = regs->regs[i];
        }
        env->PC = regs->cp0_epc;
#ifdef MIPS_USES_FPU
        env->CP0_Status |= (1 << CP0St_CU1);
#endif
    }
#elif defined(TARGET_SH4)
    {
        int i;

        for(i = 0; i < 16; i++) {
            env->gregs[i] = regs->regs[i];
        }
        env->pc = regs->pc;
    }
#else
#error unsupported target CPU
#endif

    if (gdbstub_port) {
        gdbserver_start (gdbstub_port);
        gdb_handlesig(env, 0);
    }
    cpu_loop(env);
    /* never exits */
    return 0;
}