kolos_assembler

// kolos.cpp : Defines the entry point for the console application.
//

#include "stdafx.h"
#include <cstdio>

typedef union {
	unsigned char BYTE;
	struct {
		unsigned char a : 1;
		unsigned char b : 3;
		unsigned char c : 4;
	}bits;
}un_X;

int main()
{
	un_X x;
	x.BYTE = 0xec;

	std::printf("x.BYTE = 0x%X\n", x.BYTE);
	std::printf("x.bits.a = 0x%X\n", x.bits.a);
	std::printf("x.bits.b = 0x%X\n", x.bits.b);
	std::printf("x.bits.c = 0x%X\n", x.bits.c);

	//x.bits.c = x.bits.b ^ x.bits.c ^ x.bits.a;

	// w c++
	/*
	unsigned char a_mask = 0x01;
	unsigned char b_mask = 0x0e;
	unsigned char c_mask = 0xf0;

	unsigned char a = (x.BYTE & a_mask);
	unsigned char b = ((x.BYTE & b_mask) >> 1);
	unsigned char c = ((x.BYTE & c_mask) >> 4);

	unsigned char result = (b ^ c ^ a);
	x.BYTE &= 0x0f;
	x.BYTE |= (result << 4);
	*/

	_asm {
		mov dl, x.BYTE
		mov ah, 0x01; a_mask
		mov bh, 0x0e; b_mask
		mov ch, 0xf0; c_mask

		mov al, dl; a
		and al, ah

		mov bl, dl; b
		and bl, bh
		shr bl, 1

		mov cl, dl; c
		and cl, ch
		shr cl, 4

		mov dh, bl; result
		xor dh, cl
		xor dh, al

		; bits.c = (...)
		and dl, 0x0f
		shl dh, 4
		or dl, dh

		mov x.BYTE, dl
	}

	std::printf("x.BYTE = 0x%X\n", x.BYTE);
	std::printf("x.bits.a = 0x%X\n", x.bits.a);
	std::printf("x.bits.b = 0x%X\n", x.bits.b);
	std::printf("x.bits.c = 0x%X\n", x.bits.c);

	std::getchar();
    return 0;
}