ops.c

MIPS处理器的bootloader,龙芯就是用的修改过的PMON2

/****************************************************************************
REMARKS:
Handles opcode 0x5a
****************************************************************************/
static void x86emuOp_pop_DX(u8 X86EMU_UNUSED(op1))
{
    START_OF_INSTR();
    if (M.x86.mode & SYSMODE_PREFIX_DATA) {
        DECODE_PRINTF("POP\tEDX\n");
    } else {
        DECODE_PRINTF("POP\tDX\n");
    }
    TRACE_AND_STEP();
    if (M.x86.mode & SYSMODE_PREFIX_DATA) {
        M.x86.R_EDX = pop_long();
    } else {
        M.x86.R_DX = pop_word();
    }
    DECODE_CLEAR_SEGOVR();
    END_OF_INSTR();
}

/****************************************************************************
REMARKS:
Handles opcode 0x5b
****************************************************************************/
static void x86emuOp_pop_BX(u8 X86EMU_UNUSED(op1))
{
    START_OF_INSTR();
    if (M.x86.mode & SYSMODE_PREFIX_DATA) {
        DECODE_PRINTF("POP\tEBX\n");
    } else {
        DECODE_PRINTF("POP\tBX\n");
    }
    TRACE_AND_STEP();
    if (M.x86.mode & SYSMODE_PREFIX_DATA) {
        M.x86.R_EBX = pop_long();
    } else {
        M.x86.R_BX = pop_word();
    }
    DECODE_CLEAR_SEGOVR();
    END_OF_INSTR();
}

/****************************************************************************
REMARKS:
Handles opcode 0x5c
****************************************************************************/
static void x86emuOp_pop_SP(u8 X86EMU_UNUSED(op1))
{
    START_OF_INSTR();
    if (M.x86.mode & SYSMODE_PREFIX_DATA) {
        DECODE_PRINTF("POP\tESP\n");
    } else {
        DECODE_PRINTF("POP\tSP\n");
    }
    TRACE_AND_STEP();
    if (M.x86.mode & SYSMODE_PREFIX_DATA) {
        M.x86.R_ESP = pop_long();
    } else {
        M.x86.R_SP = pop_word();
    }
    DECODE_CLEAR_SEGOVR();
    END_OF_INSTR();
}

/****************************************************************************
REMARKS:
Handles opcode 0x5d
****************************************************************************/
static void x86emuOp_pop_BP(u8 X86EMU_UNUSED(op1))
{
    START_OF_INSTR();
    if (M.x86.mode & SYSMODE_PREFIX_DATA) {
        DECODE_PRINTF("POP\tEBP\n");
    } else {
        DECODE_PRINTF("POP\tBP\n");
    }
    TRACE_AND_STEP();
    if (M.x86.mode & SYSMODE_PREFIX_DATA) {
        M.x86.R_EBP = pop_long();
    } else {
        M.x86.R_BP = pop_word();
    }
    DECODE_CLEAR_SEGOVR();
    END_OF_INSTR();
}

/****************************************************************************
REMARKS:
Handles opcode 0x5e
****************************************************************************/
static void x86emuOp_pop_SI(u8 X86EMU_UNUSED(op1))
{
    START_OF_INSTR();
    if (M.x86.mode & SYSMODE_PREFIX_DATA) {
        DECODE_PRINTF("POP\tESI\n");
    } else {
        DECODE_PRINTF("POP\tSI\n");
    }
    TRACE_AND_STEP();
    if (M.x86.mode & SYSMODE_PREFIX_DATA) {
        M.x86.R_ESI = pop_long();
    } else {
        M.x86.R_SI = pop_word();
    }
    DECODE_CLEAR_SEGOVR();
    END_OF_INSTR();
}

/****************************************************************************
REMARKS:
Handles opcode 0x5f
****************************************************************************/
static void x86emuOp_pop_DI(u8 X86EMU_UNUSED(op1))
{
    START_OF_INSTR();
    if (M.x86.mode & SYSMODE_PREFIX_DATA) {
        DECODE_PRINTF("POP\tEDI\n");
    } else {
        DECODE_PRINTF("POP\tDI\n");
    }
    TRACE_AND_STEP();
    if (M.x86.mode & SYSMODE_PREFIX_DATA) {
        M.x86.R_EDI = pop_long();
    } else {
        M.x86.R_DI = pop_word();
    }
    DECODE_CLEAR_SEGOVR();
    END_OF_INSTR();
}

/****************************************************************************
REMARKS:
Handles opcode 0x60
****************************************************************************/
static void x86emuOp_push_all(u8 X86EMU_UNUSED(op1))
{
    START_OF_INSTR();
    if (M.x86.mode & SYSMODE_PREFIX_DATA) {
        DECODE_PRINTF("PUSHAD\n");
    } else {
        DECODE_PRINTF("PUSHA\n");
    }
    TRACE_AND_STEP();
    if (M.x86.mode & SYSMODE_PREFIX_DATA) {
        u32 old_sp = M.x86.R_ESP;

        push_long(M.x86.R_EAX);
        push_long(M.x86.R_ECX);
        push_long(M.x86.R_EDX);
        push_long(M.x86.R_EBX);
        push_long(old_sp);
        push_long(M.x86.R_EBP);
        push_long(M.x86.R_ESI);
        push_long(M.x86.R_EDI);
    } else {
        u16 old_sp = M.x86.R_SP;

        push_word(M.x86.R_AX);
        push_word(M.x86.R_CX);
        push_word(M.x86.R_DX);
        push_word(M.x86.R_BX);
        push_word(old_sp);
        push_word(M.x86.R_BP);
        push_word(M.x86.R_SI);
        push_word(M.x86.R_DI);
    }
    DECODE_CLEAR_SEGOVR();
    END_OF_INSTR();
}

/****************************************************************************
REMARKS:
Handles opcode 0x61
****************************************************************************/
static void x86emuOp_pop_all(u8 X86EMU_UNUSED(op1))
{
    START_OF_INSTR();
    if (M.x86.mode & SYSMODE_PREFIX_DATA) {
        DECODE_PRINTF("POPAD\n");
    } else {
        DECODE_PRINTF("POPA\n");
    }
    TRACE_AND_STEP();
    if (M.x86.mode & SYSMODE_PREFIX_DATA) {
        M.x86.R_EDI = pop_long();
        M.x86.R_ESI = pop_long();
        M.x86.R_EBP = pop_long();
        M.x86.R_ESP += 4;              /* skip ESP */
        M.x86.R_EBX = pop_long();
        M.x86.R_EDX = pop_long();
        M.x86.R_ECX = pop_long();
        M.x86.R_EAX = pop_long();
    } else {
        M.x86.R_DI = pop_word();
        M.x86.R_SI = pop_word();
        M.x86.R_BP = pop_word();
        M.x86.R_SP += 2;               /* skip SP */
        M.x86.R_BX = pop_word();
        M.x86.R_DX = pop_word();
        M.x86.R_CX = pop_word();
        M.x86.R_AX = pop_word();
    }
    DECODE_CLEAR_SEGOVR();
    END_OF_INSTR();
}

/*opcode 0x62   ILLEGAL OP, calls x86emuOp_illegal_op() */
/*opcode 0x63   ILLEGAL OP, calls x86emuOp_illegal_op() */

/****************************************************************************
REMARKS:
Handles opcode 0x64
****************************************************************************/
static void x86emuOp_segovr_FS(u8 X86EMU_UNUSED(op1))
{
    START_OF_INSTR();
    DECODE_PRINTF("FS:\n");
    TRACE_AND_STEP();
    M.x86.mode |= SYSMODE_SEGOVR_FS;
    /*
     * 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 0x65
****************************************************************************/
static void x86emuOp_segovr_GS(u8 X86EMU_UNUSED(op1))
{
    START_OF_INSTR();
    DECODE_PRINTF("GS:\n");
    TRACE_AND_STEP();
    M.x86.mode |= SYSMODE_SEGOVR_GS;
    /*
     * 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 0x66 - prefix for 32-bit register
****************************************************************************/
static void x86emuOp_prefix_data(u8 X86EMU_UNUSED(op1))
{
    START_OF_INSTR();
    DECODE_PRINTF("DATA:\n");
    TRACE_AND_STEP();
    M.x86.mode |= SYSMODE_PREFIX_DATA;
    /* note no DECODE_CLEAR_SEGOVR here. */
    END_OF_INSTR();
}

/****************************************************************************
REMARKS:
Handles opcode 0x67 - prefix for 32-bit address
****************************************************************************/
static void x86emuOp_prefix_addr(u8 X86EMU_UNUSED(op1))
{
    START_OF_INSTR();
    DECODE_PRINTF("ADDR:\n");
    TRACE_AND_STEP();
    M.x86.mode |= SYSMODE_PREFIX_ADDR;
    /* note no DECODE_CLEAR_SEGOVR here. */
    END_OF_INSTR();
}

/****************************************************************************
REMARKS:
Handles opcode 0x68
****************************************************************************/
static void x86emuOp_push_word_IMM(u8 X86EMU_UNUSED(op1))
{
    u32 imm;

    START_OF_INSTR();
    if (M.x86.mode & SYSMODE_PREFIX_DATA) {
        imm = fetch_long_imm();
    } else {
        imm = fetch_word_imm();
    }
    DECODE_PRINTF2("PUSH\t%x\n", imm);
    TRACE_AND_STEP();
    if (M.x86.mode & SYSMODE_PREFIX_DATA) {
        push_long(imm);
    } else {
        push_word((u16)imm);
    }
    DECODE_CLEAR_SEGOVR();
    END_OF_INSTR();
}

/****************************************************************************
REMARKS:
Handles opcode 0x69
****************************************************************************/
static void x86emuOp_imul_word_IMM(u8 X86EMU_UNUSED(op1))
{
    int mod, rl, rh;
    uint srcoffset;

    START_OF_INSTR();
    DECODE_PRINTF("IMUL\t");
    FETCH_DECODE_MODRM(mod, rh, rl);
    switch (mod) {
    case 0:
        if (M.x86.mode & SYSMODE_PREFIX_DATA) {
            u32 *destreg;
            u32 srcval;
            u32 res_lo,res_hi;
            s32 imm;

            destreg = DECODE_RM_LONG_REGISTER(rh);
            DECODE_PRINTF(",");
            srcoffset = decode_rm00_address(rl);
            srcval = fetch_data_long(srcoffset);
            imm = fetch_long_imm();
            DECODE_PRINTF2(",%d\n", (s32)imm);
            TRACE_AND_STEP();
            imul_long_direct(&res_lo,&res_hi,(s32)srcval,(s32)imm);
            if (res_hi != 0) {
                SET_FLAG(F_CF);
                SET_FLAG(F_OF);
            } else {
                CLEAR_FLAG(F_CF);
                CLEAR_FLAG(F_OF);
            }
            *destreg = (u32)res_lo;
        } else {
            u16 *destreg;
            u16 srcval;
            u32 res;
            s16 imm;

            destreg = DECODE_RM_WORD_REGISTER(rh);
            DECODE_PRINTF(",");
            srcoffset = decode_rm00_address(rl);
            srcval = fetch_data_word(srcoffset);
            imm = fetch_word_imm();
            DECODE_PRINTF2(",%d\n", (s32)imm);
            TRACE_AND_STEP();
            res = (s16)srcval * (s16)imm;
            if (res > 0xFFFF) {
                SET_FLAG(F_CF);
                SET_FLAG(F_OF);
            } else {
                CLEAR_FLAG(F_CF);
                CLEAR_FLAG(F_OF);
            }
            *destreg = (u16)res;
        }
        break;
    case 1:
        if (M.x86.mode & SYSMODE_PREFIX_DATA) {
            u32 *destreg;
            u32 srcval;
            u32 res_lo,res_hi;
            s32 imm;

            destreg = DECODE_RM_LONG_REGISTER(rh);
            DECODE_PRINTF(",");
            srcoffset = decode_rm01_address(rl);
            srcval = fetch_data_long(srcoffset);
            imm = fetch_long_imm();
            DECODE_PRINTF2(",%d\n", (s32)imm);
            TRACE_AND_STEP();
            imul_long_direct(&res_lo,&res_hi,(s32)srcval,(s32)imm);
            if (res_hi != 0) {
                SET_FLAG(F_CF);
                SET_FLAG(F_OF);
            } else {
                CLEAR_FLAG(F_CF);
                CLEAR_FLAG(F_OF);
            }
            *destreg = (u32)res_lo;
        } else {
            u16 *destreg;
            u16 srcval;
            u32 res;
            s16 imm;

            destreg = DECODE_RM_WORD_REGISTER(rh);
            DECODE_PRINTF(",");
            srcoffset = decode_rm01_address(rl);
            srcval = fetch_data_word(srcoffset);
            imm = fetch_word_imm();
            DECODE_PRINTF2(",%d\n", (s32)imm);
            TRACE_AND_STEP();
            res = (s16)srcval * (s16)imm;
            if (res > 0xFFFF) {
                SET_FLAG(F_CF);
                SET_FLAG(F_OF);
            } else {
                CLEAR_FLAG(F_CF);
                CLEAR_FLAG(F_OF);
            }
            *destreg = (u16)res;
        }
        break;
    case 2:
        if (M.x86.mode & SYSMODE_PREFIX_DATA) {
            u32 *destreg;
            u32 srcval;
            u32 res_lo,res_hi;
            s32 imm;

            destreg = DECODE_RM_LONG_REGISTER(rh);
            DECODE_PRINTF(",");
            srcoffset = decode_rm10_address(rl);
            srcval = fetch_data_long(srcoffset);
            imm = fetch_long_imm();
            DECODE_PRINTF2(",%d\n", (s32)imm);
            TRACE_AND_STEP();
            imul_long_direct(&res_lo,&res_hi,(s32)srcval,(s32)imm);
            if (res_hi != 0) {
                SET_FLAG(F_CF);
                SET_FLAG(F_OF);
            } else {
                CLEAR_FLAG(F_CF);
                CLEAR_FLAG(F_OF);
            }
            *destreg = (u32)res_lo;
        } else {
            u16 *destreg;
            u16 srcval;