#include <x86.h>

#include <backend.h>

#define REG_SAFETY(reg)								                \
	do {									                        \
		if(reg > 15) DIE("Compiler error! Register %d is invalid!"	\
				 , reg);					                        \
	} while(0)

// TODO: Consider implementing a modrm backend that is rex-aware.

//void x86_calc_modrm(uint16_t reg, uint16_t mod)

void x86_mov_r_i64(uint8_t reg, uint64_t value)
{
	REG_SAFETY(reg);
	emit8(REXW);
	emit8(0xB8 + reg);
	emit64(value);
}

void x86_mov_rm_i64(uint8_t mode, uint16_t reg)
{
	DIE("TODO");
}

void x86_push_i32(uint32_t value)
{
	emit8(0x68);
	emit32(value);
}

/*
 * @todo
 */
void x86_push_i16(uint16_t value)
{
	DIE("NOT IMPLEMENTED");
	// 66h
	// PUSH 68
	// IMM value
}

void x86_push_i8(uint8_t value)
{
	emit8(0x6A);
	emit8(value);
}

void x86_push_r64(uint8_t reg)
{
	REG_SAFETY(reg);
	emit8(0x50 + reg);
}

void x86_push_rm64(uint8_t mode, uint8_t r, uint64_t m)
{
	REG_SAFETY(r);

	if(r > 7) {
		emit8(REXWR);
	} else if (r < 7) {
		emit8(REXW);
	}

	emit8(0xFF);

	// Calculate MODRM

	// emit MODRM byte
	// if mode = 1:
	//    disp
	// done
}