ops.c

MIPS处理器的bootloader,龙芯就是用的修改过的PMON2

            u16 *destreg,*srcreg;

            destreg = DECODE_RM_WORD_REGISTER(rh);
            DECODE_PRINTF(",");
            srcreg = DECODE_RM_WORD_REGISTER(rl);
            DECODE_PRINTF("\n");
            TRACE_AND_STEP();
            *destreg = U16_FUNC(x86emu_optab[op1].x86emu_priop)(*destreg, *srcreg);
        }
        break;
    }
    DECODE_CLEAR_SEGOVR();
    END_OF_INSTR();
}

/****************************************************************************
REMARKS:
Handles byte AL_IMM operations.
****************************************************************************/
static void x86emuOp_byte_AL_IMM(u8 X86EMU_UNUSED(op1))
{
    u8 srcval;

    START_OF_INSTR();
    DECODE_PRINTF(x86emu_optab[op1].x86emu_mnem);
    DECODE_PRINTF("AL,");
    srcval = fetch_byte_imm();
    DECODE_PRINTF2("%x\n", srcval);
    TRACE_AND_STEP();
    M.x86.R_AL = U8_FUNC(x86emu_optab[op1].x86emu_priop)(M.x86.R_AL, srcval);
    DECODE_CLEAR_SEGOVR();
    END_OF_INSTR();
}

/****************************************************************************
REMARKS:
Handles word and long AX_IMM operations.
****************************************************************************/
static void x86emuOp_word_AX_IMM(u8 X86EMU_UNUSED(op1))
{
    u32 srcval;

    START_OF_INSTR();
    DECODE_PRINTF(x86emu_optab[op1].x86emu_mnem);
    if (M.x86.mode & SYSMODE_PREFIX_DATA) {
        DECODE_PRINTF("EAX,");
        srcval = fetch_long_imm();
    } else {
        DECODE_PRINTF("AX,");
        srcval = fetch_word_imm();
    }
    DECODE_PRINTF2("%x\n", srcval);
    TRACE_AND_STEP();
    if (M.x86.mode & SYSMODE_PREFIX_DATA) {
        M.x86.R_EAX = U32_FUNC(x86emu_optab[op1].x86emu_priopl)(M.x86.R_EAX, srcval);
    } else {
        M.x86.R_AX = U16_FUNC(x86emu_optab[op1].x86emu_priop)(M.x86.R_AX, (u16)srcval);
    }
    DECODE_CLEAR_SEGOVR();
    END_OF_INSTR();
}

/****************************************************************************
REMARKS:
Handles opcode 0x06
****************************************************************************/
static void x86emuOp_push_ES(u8 X86EMU_UNUSED(op1))
{
    START_OF_INSTR();
    DECODE_PRINTF("PUSH\tES\n");
    TRACE_AND_STEP();
    push_word(M.x86.R_ES);
    DECODE_CLEAR_SEGOVR();
    END_OF_INSTR();
}

/****************************************************************************
REMARKS:
Handles opcode 0x07
****************************************************************************/
static void x86emuOp_pop_ES(u8 X86EMU_UNUSED(op1))
{
    START_OF_INSTR();
    DECODE_PRINTF("POP\tES\n");
    TRACE_AND_STEP();
    M.x86.R_ES = pop_word();
    DECODE_CLEAR_SEGOVR();
    END_OF_INSTR();
}

/****************************************************************************
REMARKS:
Handles opcode 0x0e
****************************************************************************/
static void x86emuOp_push_CS(u8 X86EMU_UNUSED(op1))
{
    START_OF_INSTR();
    DECODE_PRINTF("PUSH\tCS\n");
    TRACE_AND_STEP();
    push_word(M.x86.R_CS);
    DECODE_CLEAR_SEGOVR();
    END_OF_INSTR();
}

/****************************************************************************
REMARKS:
Handles opcode 0x0f. Escape for two-byte opcode (286 or better)
****************************************************************************/
static void x86emuOp_two_byte(u8 X86EMU_UNUSED(op1))
{
    u8 op2 = (*sys_rdb)(((u32)M.x86.R_CS << 4) + (M.x86.R_IP++));
    INC_DECODED_INST_LEN(1);
    (*x86emu_optab2[op2])(op2);
}

/****************************************************************************
REMARKS:
Handles opcode 0x16
****************************************************************************/
static void x86emuOp_push_SS(u8 X86EMU_UNUSED(op1))
{
    START_OF_INSTR();
    DECODE_PRINTF("PUSH\tSS\n");
    TRACE_AND_STEP();
    push_word(M.x86.R_SS);
    DECODE_CLEAR_SEGOVR();
    END_OF_INSTR();
}

/****************************************************************************
REMARKS:
Handles opcode 0x17
****************************************************************************/
static void x86emuOp_pop_SS(u8 X86EMU_UNUSED(op1))
{
    START_OF_INSTR();
    DECODE_PRINTF("POP\tSS\n");
    TRACE_AND_STEP();
    M.x86.R_SS = pop_word();
    DECODE_CLEAR_SEGOVR();
    END_OF_INSTR();
}

/****************************************************************************
REMARKS:
Handles opcode 0x1e
****************************************************************************/
static void x86emuOp_push_DS(u8 X86EMU_UNUSED(op1))
{
    START_OF_INSTR();
    DECODE_PRINTF("PUSH\tDS\n");
    TRACE_AND_STEP();
    push_word(M.x86.R_DS);
    DECODE_CLEAR_SEGOVR();
    END_OF_INSTR();
}

/****************************************************************************
REMARKS:
Handles opcode 0x1f
****************************************************************************/
static void x86emuOp_pop_DS(u8 X86EMU_UNUSED(op1))
{
    START_OF_INSTR();
    DECODE_PRINTF("POP\tDS\n");
    TRACE_AND_STEP();
    M.x86.R_DS = pop_word();
    DECODE_CLEAR_SEGOVR();
    END_OF_INSTR();
}

/****************************************************************************
REMARKS:
Handles opcode 0x26
****************************************************************************/
static void x86emuOp_segovr_ES(u8 X86EMU_UNUSED(op1))
{
    START_OF_INSTR();
    DECODE_PRINTF("ES:\n");
    TRACE_AND_STEP();
    M.x86.mode |= SYSMODE_SEGOVR_ES;
    /*
     * note the lack of DECODE_CLEAR_SEGOVR(r) since, here is one of 4
     * opcode subroutines we do not want to do this.
     */
    END_OF_INSTR();
}

/****************************************************************************
REMARKS:
Handles opcode 0x27
****************************************************************************/
static void x86emuOp_daa(u8 X86EMU_UNUSED(op1))
{
    START_OF_INSTR();
    DECODE_PRINTF("DAA\n");
    TRACE_AND_STEP();
    M.x86.R_AL = daa_byte(M.x86.R_AL);
    DECODE_CLEAR_SEGOVR();
    END_OF_INSTR();
}

/****************************************************************************
REMARKS:
Handles opcode 0x2e
****************************************************************************/
static void x86emuOp_segovr_CS(u8 X86EMU_UNUSED(op1))
{
    START_OF_INSTR();
    DECODE_PRINTF("CS:\n");
    TRACE_AND_STEP();
    M.x86.mode |= SYSMODE_SEGOVR_CS;
    /* note no DECODE_CLEAR_SEGOVR here. */
    END_OF_INSTR();
}

/****************************************************************************
REMARKS:
Handles opcode 0x2f
****************************************************************************/
static void x86emuOp_das(u8 X86EMU_UNUSED(op1))
{
    START_OF_INSTR();
    DECODE_PRINTF("DAS\n");
    TRACE_AND_STEP();
    M.x86.R_AL = das_byte(M.x86.R_AL);
    DECODE_CLEAR_SEGOVR();
    END_OF_INSTR();
}

/****************************************************************************
REMARKS:
Handles opcode 0x36
****************************************************************************/
static void x86emuOp_segovr_SS(u8 X86EMU_UNUSED(op1))
{
    START_OF_INSTR();
    DECODE_PRINTF("SS:\n");
    TRACE_AND_STEP();
    M.x86.mode |= SYSMODE_SEGOVR_SS;
    /* no DECODE_CLEAR_SEGOVR ! */
    END_OF_INSTR();
}

/****************************************************************************
REMARKS:
Handles opcode 0x37
****************************************************************************/
static void x86emuOp_aaa(u8 X86EMU_UNUSED(op1))
{
    START_OF_INSTR();
    DECODE_PRINTF("AAA\n");
    TRACE_AND_STEP();
    M.x86.R_AX = aaa_word(M.x86.R_AX);
    DECODE_CLEAR_SEGOVR();
    END_OF_INSTR();
}

/****************************************************************************
REMARKS:
Handles opcode 0x3e
****************************************************************************/
static void x86emuOp_segovr_DS(u8 X86EMU_UNUSED(op1))
{
    START_OF_INSTR();
    DECODE_PRINTF("DS:\n");
    TRACE_AND_STEP();
    M.x86.mode |= SYSMODE_SEGOVR_DS;
    /* NO DECODE_CLEAR_SEGOVR! */
    END_OF_INSTR();
}

/****************************************************************************
REMARKS:
Handles opcode 0x3f
****************************************************************************/
static void x86emuOp_aas(u8 X86EMU_UNUSED(op1))
{
    START_OF_INSTR();
    DECODE_PRINTF("AAS\n");
    TRACE_AND_STEP();
    M.x86.R_AX = aas_word(M.x86.R_AX);
    DECODE_CLEAR_SEGOVR();
    END_OF_INSTR();
}

/****************************************************************************
REMARKS:
Handles opcode 0x40
****************************************************************************/
static void x86emuOp_inc_AX(u8 X86EMU_UNUSED(op1))
{
    START_OF_INSTR();
    if (M.x86.mode & SYSMODE_PREFIX_DATA) {
        DECODE_PRINTF("INC\tEAX\n");
    } else {
        DECODE_PRINTF("INC\tAX\n");
    }
    TRACE_AND_STEP();
    if (M.x86.mode & SYSMODE_PREFIX_DATA) {
        M.x86.R_EAX = inc_long(M.x86.R_EAX);
    } else {
        M.x86.R_AX = inc_word(M.x86.R_AX);
    }
    DECODE_CLEAR_SEGOVR();
    END_OF_INSTR();
}

/****************************************************************************
REMARKS:
Handles opcode 0x41
****************************************************************************/
static void x86emuOp_inc_CX(u8 X86EMU_UNUSED(op1))
{
    START_OF_INSTR();
    if (M.x86.mode & SYSMODE_PREFIX_DATA) {
        DECODE_PRINTF("INC\tECX\n");
    } else {
        DECODE_PRINTF("INC\tCX\n");
    }
    TRACE_AND_STEP();
    if (M.x86.mode & SYSMODE_PREFIX_DATA) {
        M.x86.R_ECX = inc_long(M.x86.R_ECX);
    } else {
        M.x86.R_CX = inc_word(M.x86.R_CX);
    }
    DECODE_CLEAR_SEGOVR();
    END_OF_INSTR();
}

/****************************************************************************
REMARKS:
Handles opcode 0x42
****************************************************************************/
static void x86emuOp_inc_DX(u8 X86EMU_UNUSED(op1))
{
    START_OF_INSTR();
    if (M.x86.mode & SYSMODE_PREFIX_DATA) {
        DECODE_PRINTF("INC\tEDX\n");
    } else {
        DECODE_PRINTF("INC\tDX\n");
    }
    TRACE_AND_STEP();
    if (M.x86.mode & SYSMODE_PREFIX_DATA) {
        M.x86.R_EDX = inc_long(M.x86.R_EDX);
    } else {
        M.x86.R_DX = inc_word(M.x86.R_DX);
    }
    DECODE_CLEAR_SEGOVR();
    END_OF_INSTR();
}

/****************************************************************************
REMARKS:
Handles opcode 0x43
****************************************************************************/
static void x86emuOp_inc_BX(u8 X86EMU_UNUSED(op1))
{
    START_OF_INSTR();
    if (M.x86.mode & SYSMODE_PREFIX_DATA) {
        DECODE_PRINTF("INC\tEBX\n");
    } else {
        DECODE_PRINTF("INC\tBX\n");
    }
    TRACE_AND_STEP();
    if (M.x86.mode & SYSMODE_PREFIX_DATA) {
        M.x86.R_EBX = inc_long(M.x86.R_EBX);
    } else {
        M.x86.R_BX = inc_word(M.x86.R_BX);
    }
    DECODE_CLEAR_SEGOVR();
    END_OF_INSTR();
}

/****************************************************************************
REMARKS:
Handles opcode 0x44
****************************************************************************/
static void x86emuOp_inc_SP(u8 X86EMU_UNUSED(op1))
{
    START_OF_INSTR();
    if (M.x86.mode & SYSMODE_PREFIX_DATA) {
        DECODE_PRINTF("INC\tESP\n");
    } else {
        DECODE_PRINTF("INC\tSP\n");
    }
    TRACE_AND_STEP();
    if (M.x86.mode & SYSMODE_PREFIX_DATA) {
        M.x86.R_ESP = inc_long(M.x86.R_ESP);
    } else {
        M.x86.R_SP = inc_word(M.x86.R_SP);
    }
    DECODE_CLEAR_SEGOVR();
    END_OF_INSTR();
}

/****************************************************************************
REMARKS:
Handles opcode 0x45
****************************************************************************/
static void x86emuOp_inc_BP(u8 X86EMU_UNUSED(op1))
{
    START_OF_INSTR();
    if (M.x86.mode & SYSMODE_PREFIX_DATA) {
        DECODE_PRINTF("INC\tEBP\n");
    } else {
        DECODE_PRINTF("INC\tBP\n");
    }
    TRACE_AND_STEP();
    if (M.x86.mode & SYSMODE_PREFIX_DATA) {
        M.x86.R_EBP = inc_long(M.x86.R_EBP);
    } else {
        M.x86.R_BP = inc_word(M.x86.R_BP);
    }
    DECODE_CLEAR_SEGOVR();
    END_OF_INSTR();
}

/****************************************************************************
REMARKS:
Handles opcode 0x46
****************************************************************************/
static void x86emuOp_inc_SI(u8 X86EMU_UNUSED(op1))
{
    START_OF_INSTR();
    if (M.x86.mode & SYSMODE_PREFIX_DATA) {
        DECODE_PRINTF("INC\tESI\n");
    } else {
        DECODE_PRINTF("INC\tSI\n");
    }
    TRACE_AND_STEP();