translate-copy.c

qemu虚拟机代码

    case 0x1a4: /* shld imm */
    case 0x1ac: /* shrd imm */
        modrm = ldub_code(s->pc++);
        parse_modrm(s, modrm);
        ldub_code(s->pc++);
        break;
        
        /************************/
        /* string ops */

    case 0xa4: /* movsS */
    case 0xa5:
        break;
        
    case 0xaa: /* stosS */
    case 0xab:
        break;

    case 0xac: /* lodsS */
    case 0xad:
        break;

    case 0xae: /* scasS */
    case 0xaf:
        break;

    case 0xa6: /* cmpsS */
    case 0xa7:
        break;

    case 0x6c: /* insS */
    case 0x6d:
        goto unsupported_op;

    case 0x6e: /* outsS */
    case 0x6f:
        goto unsupported_op;

        /************************/
        /* port I/O */
    case 0xe4:
    case 0xe5:
        goto unsupported_op;

    case 0xe6:
    case 0xe7:
        goto unsupported_op;

    case 0xec:
    case 0xed:
        goto unsupported_op;

    case 0xee:
    case 0xef:
        goto unsupported_op;

        /************************/
        /* control */
#if 0
    case 0xc2: /* ret im */
        val = ldsw_code(s->pc);
        s->pc += 2;
        gen_pop_T0(s);
        gen_stack_update(s, val + (2 << s->dflag));
        if (s->dflag == 0)
            gen_op_andl_T0_ffff();
        gen_op_jmp_T0();
        gen_eob(s);
        break;
#endif

    case 0xc3: /* ret */
        gb(s, CPU_SEG);
        if (!s->dflag)  
            gb(s, 0x66); /* d16 */
        gb(s, 0x8f); /* pop addr */
        gb(s, 0x05);
        gl(s, CPU_FIELD_OFFSET(eip));
        if (!s->dflag) {
            /* reset high bits of EIP */
            gen_movw_addr_im(s, CPU_FIELD_OFFSET(eip) + 2, 0);
        }
        gen_eob(s);
        goto no_copy;
    case 0xca: /* lret im */
    case 0xcb: /* lret */
    case 0xcf: /* iret */
    case 0x9a: /* lcall im */
    case 0xea: /* ljmp im */
        goto unsupported_op;

    case 0xe8: /* call im */
        ot = dflag ? OT_LONG : OT_WORD;
        val = insn_get(s, ot);
        next_eip = s->pc - s->cs_base;
        val += next_eip;
        if (s->dflag) {
            gb(s, 0x68); /* pushl imm */
            gl(s, next_eip);
        } else {
            gb(s, 0x66); /* pushw imm */
            gb(s, 0x68);
            gw(s, next_eip);
            val &= 0xffff;
        }
        gen_jmp(s, val);
        goto no_copy;
    case 0xe9: /* jmp */
        ot = dflag ? OT_LONG : OT_WORD;
        val = insn_get(s, ot);
        val += s->pc - s->cs_base;
        if (s->dflag == 0)
            val = val & 0xffff;
        gen_jmp(s, val);
        goto no_copy;
    case 0xeb: /* jmp Jb */
        val = (int8_t)insn_get(s, OT_BYTE);
        val += s->pc - s->cs_base;
        if (s->dflag == 0)
            val = val & 0xffff;
        gen_jmp(s, val);
        goto no_copy;
    case 0x70 ... 0x7f: /* jcc Jb */
        val = (int8_t)insn_get(s, OT_BYTE);
        goto do_jcc;
    case 0x180 ... 0x18f: /* jcc Jv */
        if (dflag) {
            val = insn_get(s, OT_LONG);
        } else {
            val = (int16_t)insn_get(s, OT_WORD); 
        }
    do_jcc:
        next_eip = s->pc - s->cs_base;
        val += next_eip;
        if (s->dflag == 0)
            val &= 0xffff;
        gen_jcc(s, b & 0xf, val, next_eip);
        goto no_copy;

        /************************/
        /* flags */
    case 0x9c: /* pushf */
        /* XXX: put specific code ? */
        goto unsupported_op;
    case 0x9d: /* popf */
        goto unsupported_op;

    case 0x9e: /* sahf */
    case 0x9f: /* lahf */
    case 0xf5: /* cmc */
    case 0xf8: /* clc */
    case 0xf9: /* stc */
    case 0xfc: /* cld */
    case 0xfd: /* std */
        break;

        /************************/
        /* bit operations */
    case 0x1ba: /* bt/bts/btr/btc Gv, im */
        ot = dflag ? OT_LONG : OT_WORD;
        modrm = ldub_code(s->pc++);
        op = (modrm >> 3) & 7;
        parse_modrm(s, modrm);
        /* load shift */
        ldub_code(s->pc++);
        if (op < 4)
            goto illegal_op;
        break;
        /************************/
        /* bcd */
    case 0x27: /* daa */
        break;
    case 0x2f: /* das */
        break;
    case 0x37: /* aaa */
        break;
    case 0x3f: /* aas */
        break;
    case 0xd4: /* aam */
        ldub_code(s->pc++);
        break;
    case 0xd5: /* aad */
        ldub_code(s->pc++);
        break;
        /************************/
        /* misc */
    case 0x90: /* nop */
        break;
    case 0x9b: /* fwait */
        if ((s->flags & (HF_MP_MASK | HF_TS_MASK)) == 
            (HF_MP_MASK | HF_TS_MASK)) {
            goto unsupported_op;
        }
        break;
    case 0xcc: /* int3 */
        goto unsupported_op;
    case 0xcd: /* int N */
        goto unsupported_op;
    case 0xce: /* into */
        goto unsupported_op;
    case 0xf1: /* icebp (undocumented, exits to external debugger) */
        goto unsupported_op;
    case 0xfa: /* cli */
        goto unsupported_op;
    case 0xfb: /* sti */
        goto unsupported_op;
    case 0x62: /* bound */
        modrm = ldub_code(s->pc++);
        mod = (modrm >> 6) & 3;
        if (mod == 3)
            goto illegal_op;
        parse_modrm(s, modrm);
        break;
    case 0x1c8 ... 0x1cf: /* bswap reg */
        break;
    case 0xd6: /* salc */
        break;
    case 0xe0: /* loopnz */
    case 0xe1: /* loopz */
    case 0xe2: /* loop */
    case 0xe3: /* jecxz */
        goto unsupported_op;

    case 0x130: /* wrmsr */
    case 0x132: /* rdmsr */
        goto unsupported_op;
    case 0x131: /* rdtsc */
        goto unsupported_op;
    case 0x1a2: /* cpuid */
        goto unsupported_op;
    case 0xf4: /* hlt */
        goto unsupported_op;
    case 0x100:
        goto unsupported_op;
    case 0x101:
        goto unsupported_op;
    case 0x108: /* invd */
    case 0x109: /* wbinvd */
        goto unsupported_op;
    case 0x63: /* arpl */
        goto unsupported_op;
    case 0x102: /* lar */
    case 0x103: /* lsl */
        goto unsupported_op;
    case 0x118:
        goto unsupported_op;
    case 0x120: /* mov reg, crN */
    case 0x122: /* mov crN, reg */
        goto unsupported_op;
    case 0x121: /* mov reg, drN */
    case 0x123: /* mov drN, reg */
        goto unsupported_op;
    case 0x106: /* clts */
        goto unsupported_op;
    default:
        goto illegal_op;
    }

    /* just copy the code */

    /* no override yet */
    if (!s->dflag)
        gb(s, 0x66);
    if (!s->aflag)
        gb(s, 0x67);
    if (prefixes & PREFIX_REPZ)
        gb(s, 0xf3);
    else if (prefixes & PREFIX_REPNZ)
        gb(s, 0xf2);
    {
        int len, i;
        len = s->pc - pc_start_insn;
        for(i = 0; i < len; i++) {
            *s->gen_code_ptr++ = ldub_code(pc_start_insn + i);
        }
    }
 no_copy:
    return 0;
 illegal_op:
 unsupported_op:
    /* fall back to slower code gen necessary */
    s->pc = pc_start;
    return -1;
}

#define GEN_CODE_MAX_SIZE      8192
#define GEN_CODE_MAX_INSN_SIZE 512

static inline int gen_intermediate_code_internal(CPUState *env,
                                                 TranslationBlock *tb, 
                                                 uint8_t *gen_code_ptr,
                                                 int *gen_code_size_ptr,
                                                 int search_pc,
                                                 uint8_t *tc_ptr)
{
    DisasContext dc1, *dc = &dc1;
    target_ulong pc_insn, pc_start, cs_base;
    uint8_t *gen_code_end;
    int flags, ret;

    if (env->nb_breakpoints > 0 ||
        env->singlestep_enabled)
        return -1;
    flags = tb->flags;
    if (flags & (HF_TF_MASK | HF_ADDSEG_MASK | 
                 HF_SOFTMMU_MASK | HF_INHIBIT_IRQ_MASK))
        return -1;
    if (!(flags & HF_SS32_MASK))
        return -1;
    if (tb->cflags & CF_SINGLE_INSN)
        return -1;
    gen_code_end = gen_code_ptr + 
        GEN_CODE_MAX_SIZE - GEN_CODE_MAX_INSN_SIZE;
    dc->gen_code_ptr = gen_code_ptr;
    dc->gen_code_start = gen_code_ptr;

    /* generate intermediate code */
    pc_start = tb->pc;
    cs_base = tb->cs_base;
    dc->pc = pc_start;
    dc->cs_base = cs_base;
    dc->pe = (flags >> HF_PE_SHIFT) & 1;
    dc->code32 = (flags >> HF_CS32_SHIFT) & 1;
    dc->f_st = 0;
    dc->vm86 = (flags >> VM_SHIFT) & 1;
    dc->cpl = (flags >> HF_CPL_SHIFT) & 3;
    dc->iopl = (flags >> IOPL_SHIFT) & 3;
    dc->tb = tb;
    dc->flags = flags;

    dc->is_jmp = 0;

    for(;;) {
        pc_insn = dc->pc;
        ret = disas_insn(dc);
        if (ret < 0) {
            /* unsupported insn */
            if (dc->pc == pc_start) {
                /* if first instruction, signal that no copying was done */
                return -1;
            } else {
                gen_jmp(dc, dc->pc - dc->cs_base);
                dc->is_jmp = 1;
            }
        }
        if (search_pc) {
            /* search pc mode */
            if (tc_ptr < dc->gen_code_ptr) {
                env->eip = pc_insn - cs_base;
                return 0;
            }
        }
        /* stop translation if indicated */
        if (dc->is_jmp)
            break;
        /* if too long translation, stop generation */
        if (dc->gen_code_ptr >= gen_code_end ||
            (dc->pc - pc_start) >= (TARGET_PAGE_SIZE - 32)) {
            gen_jmp(dc, dc->pc - dc->cs_base);
            break;
        }
    }
    
#ifdef DEBUG_DISAS
    if (loglevel & CPU_LOG_TB_IN_ASM) {
        fprintf(logfile, "----------------\n");
        fprintf(logfile, "IN: COPY: %s fpu=%d\n", 
                lookup_symbol(pc_start),
                tb->cflags & CF_TB_FP_USED ? 1 : 0);
	target_disas(logfile, pc_start, dc->pc - pc_start, !dc->code32);
        fprintf(logfile, "\n");
    }
#endif

    if (!search_pc) {
        *gen_code_size_ptr = dc->gen_code_ptr - dc->gen_code_start;
        tb->size = dc->pc - pc_start;
        tb->cflags |= CF_CODE_COPY;
        return 0;
    } else {
        return -1;
    }
}

/* generate code by just copying data. Return -1 if cannot generate
   any code. Return 0 if code was generated */
int cpu_gen_code_copy(CPUState *env, TranslationBlock *tb,
                      int max_code_size, int *gen_code_size_ptr)
{
    /* generate machine code */
    tb->tb_next_offset[0] = 0xffff;
    tb->tb_next_offset[1] = 0xffff;
#ifdef USE_DIRECT_JUMP
    /* the following two entries are optional (only used for string ops) */
    tb->tb_jmp_offset[2] = 0xffff;
    tb->tb_jmp_offset[3] = 0xffff;
#endif
    return gen_intermediate_code_internal(env, tb, 
                                          tb->tc_ptr, gen_code_size_ptr,
                                          0, NULL);
}

static uint8_t dummy_gen_code_buf[GEN_CODE_MAX_SIZE];

int cpu_restore_state_copy(TranslationBlock *tb, 
                           CPUState *env, unsigned long searched_pc,
                           void *puc)
{
    struct ucontext *uc = puc;
    int ret, eflags;

    /* find opc index corresponding to search_pc */
    if (searched_pc < (unsigned long)tb->tc_ptr)
        return -1;
    searched_pc = searched_pc - (long)tb->tc_ptr + (long)dummy_gen_code_buf;
    ret = gen_intermediate_code_internal(env, tb, 
                                         dummy_gen_code_buf, NULL,
                                         1, (uint8_t *)searched_pc);
    if (ret < 0)
        return ret;
    /* restore all the CPU state from the CPU context from the
       signal. The FPU context stays in the host CPU. */
    
    env->regs[R_EAX] = uc->uc_mcontext.gregs[REG_EAX];
    env->regs[R_ECX] = uc->uc_mcontext.gregs[REG_ECX];
    env->regs[R_EDX] = uc->uc_mcontext.gregs[REG_EDX];
    env->regs[R_EBX] = uc->uc_mcontext.gregs[REG_EBX];
    env->regs[R_ESP] = uc->uc_mcontext.gregs[REG_ESP];
    env->regs[R_EBP] = uc->uc_mcontext.gregs[REG_EBP];
    env->regs[R_ESI] = uc->uc_mcontext.gregs[REG_ESI];
    env->regs[R_EDI] = uc->uc_mcontext.gregs[REG_EDI];
    eflags = uc->uc_mcontext.gregs[REG_EFL];
    env->df = 1 - (2 * ((eflags >> 10) & 1));
    env->cc_src = eflags & (CC_O | CC_S | CC_Z | CC_A | CC_P | CC_C);
    env->cc_op = CC_OP_EFLAGS;
    return 0;
}

#endif /* USE_CODE_COPY */