Exemplo n.º 1
0
void cpu_m68k_flush_flags(CPUM68KState *env, int cc_op)
{
    int flags;
    uint32_t src;
    uint32_t dest;
    uint32_t tmp;

#define HIGHBIT 0x80000000u

#define SET_NZ(x) do { \
    if ((x) == 0) \
        flags |= CCF_Z; \
    else if ((int32_t)(x) < 0) \
        flags |= CCF_N; \
    } while (0)

#define SET_FLAGS_SUB(type, utype) do { \
    SET_NZ((type)dest); \
    tmp = dest + src; \
    if ((utype) tmp < (utype) src) \
        flags |= CCF_C; \
    if ((1u << (sizeof(type) * 8 - 1)) & (tmp ^ dest) & (tmp ^ src)) \
        flags |= CCF_V; \
    } while (0)

    flags = 0;
    src = env->cc_src;
    dest = env->cc_dest;
    switch (cc_op) {
    case CC_OP_FLAGS:
        flags = dest;
        break;
    case CC_OP_LOGIC:
        SET_NZ(dest);
        break;
    case CC_OP_ADD:
        SET_NZ(dest);
        if (dest < src)
            flags |= CCF_C;
        tmp = dest - src;
        if (HIGHBIT & (src ^ dest) & ~(tmp ^ src))
            flags |= CCF_V;
        break;
    case CC_OP_SUB:
        SET_FLAGS_SUB(int32_t, uint32_t);
        break;
    case CC_OP_CMPB:
        SET_FLAGS_SUB(int8_t, uint8_t);
        break;
    case CC_OP_CMPW:
        SET_FLAGS_SUB(int16_t, uint16_t);
        break;
    case CC_OP_ADDX:
        SET_NZ(dest);
        if (dest <= src)
            flags |= CCF_C;
        tmp = dest - src - 1;
        if (HIGHBIT & (src ^ dest) & ~(tmp ^ src))
            flags |= CCF_V;
        break;
    case CC_OP_SUBX:
        SET_NZ(dest);
        tmp = dest + src + 1;
        if (tmp <= src)
            flags |= CCF_C;
        if (HIGHBIT & (tmp ^ dest) & (tmp ^ src))
            flags |= CCF_V;
        break;
    case CC_OP_SHIFT:
        SET_NZ(dest);
        if (src)
            flags |= CCF_C;
        break;
    default:
        cpu_abort(env, "Bad CC_OP %d", cc_op);
    }
    env->cc_op = CC_OP_FLAGS;
    env->cc_dest = flags;
}
Exemplo n.º 2
0
int
arch_pdp11_translate_instr(cpu_t *cpu, addr_t pc, BasicBlock *bb) {
	uint16_t opcode = cpu->RAM[pc];

//LOG("%s:%d PC=$%04X\n", __func__, __LINE__, pc);

	switch (get_instr(opcode)) {
		/* flags */
		case INSTR_CLC:	LET1(cpu->ptr_C, FALSE);				break;
		case INSTR_CLD:	LET1(ptr_D, FALSE);				break;
		case INSTR_CLI:	LET1(ptr_I, FALSE);				break;
		case INSTR_CLV:	LET1(cpu->ptr_V, FALSE);				break;
		case INSTR_SEC:	LET1(cpu->ptr_C, TRUE);				break;
		case INSTR_SED:	LET1(ptr_D, TRUE);				break;
		case INSTR_SEI:	LET1(ptr_I, TRUE);				break;

		/* register transfer */
		case INSTR_TAX:	SET_NZ(LET(X,R(A)));			break;
		case INSTR_TAY:	SET_NZ(LET(Y,R(A)));			break;
		case INSTR_TXA:	SET_NZ(LET(A,R(X)));			break;
		case INSTR_TYA:	SET_NZ(LET(A,R(Y)));			break;
		case INSTR_TSX:	SET_NZ(LET(X,R(S)));			break;
		case INSTR_TXS:	SET_NZ(LET(S,R(X)));			break;

		/* load */
		case INSTR_LDA:	SET_NZ(LET(A,OPERAND));			break;
		case INSTR_LDX:	SET_NZ(LET(X,OPERAND));			break;
		case INSTR_LDY:	SET_NZ(LET(Y,OPERAND));			break;

		/* store */
		case INSTR_STA:	STORE(R(A),LOPERAND);			break;
		case INSTR_STX:	STORE(R(X),LOPERAND);			break;
		case INSTR_STY:	STORE(R(Y),LOPERAND);			break;

		/* stack */
		case INSTR_PHA:	PUSH(R(A));						break;
		case INSTR_PHP:	PUSH(arch_flags_encode(cpu, bb));	break;
		case INSTR_PLA:	SET_NZ(LET(A,PULL));			break;
		case INSTR_PLP:	arch_flags_decode(cpu, PULL, bb);	break;

		/* shift */
		case INSTR_ASL:	SET_NZ(SHIFTROTATE(LOPERAND, LOPERAND, true, false));	break;
		case INSTR_LSR:	SET_NZ(SHIFTROTATE(LOPERAND, LOPERAND, false, false));	break;
		case INSTR_ROL:	SET_NZ(SHIFTROTATE(LOPERAND, LOPERAND, true, true));	break;
		case INSTR_ROR:	SET_NZ(SHIFTROTATE(LOPERAND, LOPERAND, false, true));	break;

		/* bit logic */
		case INSTR_AND:	SET_NZ(LET(A,AND(R(A),OPERAND)));			break;
		case INSTR_ORA:	SET_NZ(LET(A,OR(R(A),OPERAND)));			break;
		case INSTR_EOR:	SET_NZ(LET(A,XOR(R(A),OPERAND)));			break;
		case INSTR_BIT:	SET_NZ(OPERAND);							break;

		/* arithmetic */
		case INSTR_ADC:	SET_NZ(ADC(ptr_A, ptr_A, OPERAND, true, false));		break;
		case INSTR_SBC:	SET_NZ(ADC(ptr_A, ptr_A, COM(OPERAND), true, false));	break;
		case INSTR_CMP:	SET_NZ(ADC(NULL, ptr_A, COM(OPERAND), false, true));		break;
		case INSTR_CPX:	SET_NZ(ADC(NULL, ptr_X, COM(OPERAND), false, true));		break;
		case INSTR_CPY:	SET_NZ(ADC(NULL, ptr_Y, COM(OPERAND), false, true));		break;

		/* increment/decrement */
		case INSTR_INX:	SET_NZ(LET(X,INC(R(X))));			break;
		case INSTR_INY:	SET_NZ(LET(Y,INC(R(Y))));			break;
		case INSTR_DEX:	SET_NZ(LET(X,DEC(R(X))));			break;
		case INSTR_DEY:	SET_NZ(LET(Y,DEC(R(Y))));			break;

		case INSTR_INC:	SET_NZ(STORE(INC(OPERAND),LOPERAND));			break;
		case INSTR_DEC:	SET_NZ(STORE(DEC(OPERAND),LOPERAND));			break;
		
		/* control flow */
		case INSTR_JMP:
			if (get_addmode(opcode) == ADDMODE_IND) {
				Value *v = LOAD_RAM16(CONST32(OPERAND_16));
				new StoreInst(v, cpu->ptr_PC, bb);
			}
			break;
		case INSTR_JSR:	PUSH16(pc+2);						break;
		case INSTR_RTS:	STORE(ADD(PULL16, CONST16(1)), cpu->ptr_PC);	break;

		/* branch */
		case INSTR_BEQ:
		case INSTR_BNE:
		case INSTR_BCS:
		case INSTR_BCC:
		case INSTR_BMI:
		case INSTR_BPL:
		case INSTR_BVS:
		case INSTR_BVC:
			break;

		/* other */
		case INSTR_NOP:											break;
		case INSTR_BRK:	arch_6502_trap(cpu, pc, bb);			break;
		case INSTR_RTI:	arch_6502_trap(cpu, pc, bb);			break;
		case INSTR_XXX:	arch_6502_trap(cpu, pc, bb);			break;
	}

	return get_length(get_addmode(opcode));
}