/*
 * ix86 core.
 *  Author: linuzappz <linuzappz@pcsx.net>
 */

#include <stdio.h>

#include "ix86.h"

void x86Init(char *ptr) {
	x86Ptr = ptr;
}

void x86Shutdown() {
}

void x86SetJ8(u8 *j8) {
	*j8 = ((u8*)x86Ptr - j8) - 1;
}

void x86SetJ32(u32 *j32) {
	*j32 = ((u32*)x86Ptr - j32) - 4;
}

#define SIB 4
#define DISP32 5

#define write8(val)  *(unsigned char *)x86Ptr = val; x86Ptr++;
#define write16(val) *(unsigned short*)x86Ptr = val; x86Ptr+=2;
#define write32(val) *(u32 *)x86Ptr = val; x86Ptr+=4;

/* macros helpers */

#define ModRM(mod, rm, reg) \
	write8((mod << 6) | (rm << 3) | (reg));

#define SibSB(ss, rm, index) \
	write8((ss << 6) | (rm << 3) | (index));

#define SET8R(cc, to) { \
	write8(0x0F); write8(cc); \
	write8((0xC0) | (to)); }

#define J8Rel(cc, to) { \
	write8(cc); write8(to); return x86Ptr - 1; }

#define CMOV32RtoR(cc, to, from) { \
	write8(0x0F); write8(cc); \
	ModRM(3, to, from); }

#define CMOV32MtoR(cc, to, from) { \
	write8(0x0F); write8(cc); \
	ModRM(0, to, DISP32); \
	write32(from); }

/********************/
/* IX86 intructions */
/********************/

// mov instructions

/* mov r32 to r32 */
void MOV32RtoR(int to, int from) {
	write8(0x89);
	ModRM(3, from, to);
}

/* mov r32 to m32 */
void MOV32RtoM(u32 to, int from) {
	write8(0x89);
	ModRM(0, from, DISP32);
	write32(to);
}

/* mov m32 to r32 */
void MOV32MtoR(int to, u32 from) {
	write8(0x8B);
	ModRM(0, to, DISP32);
	write32(from); 
}

/* mov [r32] to r32 */
void MOV32RmtoR(int to, int from) {
	write8(0x8B);
	ModRM(0, to, from);
}

/* mov [r32][r32*scale] to r32 */
void MOV32RmStoR(int to, int from, int from2, int scale) {
	write8(0x8B);
	ModRM(0, to, 0x4);
	SibSB(scale, from2, from);
}

/* mov r32 to [r32] */
void MOV32RtoRm(int to, int from) {
	write8(0x89);
	ModRM(0, from, to);
}

/* mov imm32 to r32 */
void MOV32ItoR(int to, u32 from) {
	write8(0xB8 | to); 
	write32(from);
}

/* mov imm32 to m32 */
void MOV32ItoM(u32 to, u32 from) {
	write8(0xC7);
	ModRM(0, 0, DISP32);
	write32(to);
	write32(from); 
}

/* movsx r8 to r32 */
void MOVSX32R8toR(int to, int from) {
	write16(0xBE0F); 
	ModRM(3, to, from); 
}

/* movsx r16 to r32 */
void MOVSX32R16toR(int to, int from) {
	write16(0xBF0F); 
	ModRM(3, to, from); 
}

/* movzx r8 to r32 */
void MOVZX32R8toR(int to, int from) {
	write16(0xB60F); 
	ModRM(3, to, from); 
}

/* movzx r16 to r32 */
void MOVZX32R16toR(int to, int from) {
	write16(0xB70F); 
	ModRM(3, to, from); 
}

/* cmovne r32 to r32 */
void CMOVNE32RtoR(int to, int from) {
	CMOV32RtoR(0x45, to, from);
}

/* cmovne m32 to r32*/
void CMOVNE32MtoR(int to, u32 from) {
	CMOV32MtoR(0x45, to, from);
}

/* cmove r32 to r32*/
void CMOVE32RtoR(int to, int from) {
	CMOV32RtoR(0x44, to, from);
}

/* cmove m32 to r32*/
void CMOVE32MtoR(int to, u32 from) {
	CMOV32MtoR(0x44, to, from);
}

/* cmovg r32 to r32*/
void CMOVG32RtoR(int to, int from) {
	CMOV32RtoR(0x4F, to, from);
}

/* cmovg m32 to r32*/
void CMOVG32MtoR(int to, u32 from) {
	CMOV32MtoR(0x4F, to, from);
}

/* cmovge r32 to r32*/
void CMOVGE32RtoR(int to, int from) {
	CMOV32RtoR(0x4D, to, from);
}

/* cmovge m32 to r32*/
void CMOVGE32MtoR(int to, u32 from) {
	CMOV32MtoR(0x4D, to, from);
}

/* cmovl r32 to r32*/
void CMOVL32RtoR(int to, int from) {
	CMOV32RtoR(0x4C, to, from);
}

/* cmovl m32 to r32*/
void CMOVL32MtoR(int to, u32 from) {
	CMOV32MtoR(0x4C, to, from);
}

/* cmovle r32 to r32*/
void CMOVLE32RtoR(int to, int from) {
	CMOV32RtoR(0x4E, to, from);
}

/* cmovle m32 to r32*/
void CMOVLE32MtoR(int to, u32 from) {
	CMOV32MtoR(0x4E, to, from);
}

// arithmic instructions

/* add imm32 to r32 */
void ADD32ItoR(int to, u32 from) {
	if (to == EAX) {
		write8(0x05); 
	} else {
		write8(0x81); 
		ModRM(3, 0, to);
	}
	write32(from);
}

/* add imm32 to m32 */
void ADD32ItoM(u32 to, u32 from) {
	write8(0x81); 
	ModRM(0, 0, DISP32);
	write32(to);
	write32(from);
}

/* add r32 to r32 */
void ADD32RtoR(int to, int from) {
	write8(0x01); 
	ModRM(3, from, to);
}

/* add m32 to r32 */
void ADD32MtoR(int to, u32 from) {
	write8(0x03); 
	ModRM(0, to, DISP32);
	write32(from);
}

/* adc imm32 to r32 */
void ADC32ItoR(int to, u32 from) {
	if (to == EAX) {
		write8(0x15);
	} else {
		write8(0x81);
		ModRM(3, 2, to);
	}
	write32(from); 
}

/* adc r32 to r32 */
void ADC32RtoR(int to, int from) {
	write8(0x11); 
	ModRM(3, from, to);
}

/* adc m32 to r32 */
void ADC32MtoR(int to, u32 from) {
	write8(0x13); 
	ModRM(0, to, DISP32);
	write32(from); 
}

/* sub imm32 to r32 */
void SUB32ItoR(int to, u32 from) {
	if (to == EAX) {
		write8(0x2D); 
	} else {
		write8(0x81); 
		ModRM(3, 5, to);
	}
	write32(from); 
}

/* sub r32 to r32 */
void SUB32RtoR(int to, int from) {
	write8(0x29); 
	ModRM(3, from, to);
}

/* sub m32 to r32 */
void SUB32MtoR(int to, u32 from) {
	write8(0x2B); 
	ModRM(0, to, DISP32);
	write32(from); 
}

/* sbb imm32 to r32 */
void SBB32ItoR(int to, u32 from) {
	if (to == EAX) {
		write8(0x1D);
	} else {
		write8(0x81);
		ModRM(3, 3, to);
	}
	write32(from); 
}

/* sbb r32 to r32 */
void SBB32RtoR(int to, int from) {
	write8(0x19); 
	ModRM(3, from, to);
}

/* sbb m32 to r32 */
void SBB32MtoR(int to, u32 from) {
	write8(0x1B); 
	ModRM(0, to, DISP32);
	write32(from); 
}

/* mul eax by r32 to edx:eax */
void MUL32R(int from) {
	write8(0xF7); 
	ModRM(3, 4, from);
}

/* imul eax by r32 to edx:eax */
void IMUL32R(int from) {
	write8(0xF7); 
	ModRM(3, 5, from);
}

/* mul eax by m32 to edx:eax */
void MUL32M(u32 from) {
	write8(0xF7); 
	ModRM(0, 4, DISP32);
	write32(from); 
}

/* imul eax by m32 to edx:eax */
void IMUL32M(u32 from) {
	write8(0xF7); 
	ModRM(0, 5, DISP32);
	write32(from); 
}

/* div eax by r32 to edx:eax */
void DIV32R(int from) {
	write8(0xF7); 
	ModRM(3, 6, from);
}

/* idiv eax by r32 to edx:eax */
void IDIV32R(int from) {
	write8(0xF7); 
	ModRM(3, 7, from);
}

/* div eax by m32 to edx:eax */
void DIV32M(u32 from) {
	write8(0xF7); 
	ModRM(0, 6, DISP32);
	write32(from); 
}

/* idiv eax by m32 to edx:eax */
void IDIV32M(u32 from) {
	write8(0xF7); 
	ModRM(0, 7, DISP32);
	write32(from); 
}

// shifting instructions

/* shl imm8 to r32 */
void SHL32ItoR(int to, unsigned char from) {
	write8(0xC1); 
	ModRM(3, 4, to);
	write8(from); 
}

/* shl cl to r32 */
void SHL32CLtoR(int to) {
	write8(0xD3); 
	ModRM(3, 4, to);
}

/* shr imm8 to r32 */
void SHR32ItoR(int to, unsigned char from) {
	write8(0xC1); 
	ModRM(3, 5, to);
	write8(from); 
}

/* shr cl to r32 */
void SHR32CLtoR(int to) {
	write8(0xD3); 
	ModRM(3, 5, to);
}

/* sar imm8 to r32 */
void SAR32ItoR(int to, unsigned char from) {
	write8(0xC1); 
	ModRM(3, 7, to);
	write8(from); 
}

/* sar cl to r32 */
void SAR32CLtoR(int to) {
	write8(0xD3); 
	ModRM(3, 7, to);
}


// logical instructions

/* or imm32 to r32 */
void OR32ItoR(int to, u32 from) {
	if (to == EAX) {
		write8(0x0D); 
	} else {
		write8(0x81); 
		ModRM(3, 1, to);
	}
	write32(from); 
}

/* or imm32 to m32 */
void OR32ItoM(u32 to, u32 from) {
	write8(0x81); 
	ModRM(0, 1, DISP32);
	write32(to);
	write32(from); 
}

/* or r32 to r32 */
void OR32RtoR(int to, int from) {
	write8(0x09); 
	ModRM(3, from, to);
}

/* or m32 to r32 */
void OR32MtoR(int to, u32 from) {
	write8(0x0B); 
	ModRM(0, to, DISP32);
	write32(from); 
}

/* xor imm32 to r32 */
void XOR32ItoR(int to, u32 from) {
	if (to == EAX) {
		write8(0x35); 
	} else {
		write8(0x81); 
		ModRM(3, 6, to);
	}
	write32(from); 
}

/* xor imm32 to m32 */
void XOR32ItoM(u32 to, u32 from) {
	write8(0x81); 
	ModRM(0, 6, DISP32);
	write32(to); 
	write32(from); 
}

/* xor r32 to r32 */
void XOR32RtoR(int to, int from) {
	write8(0x31); 
	ModRM(3, from, to);
}

/* xor m32 to r32 */
void XOR32MtoR(int to, u32 from) {
	write8(0x33); 
	ModRM(0, to, DISP32);
	write32(from); 
}

/* and imm32 to r32 */
void AND32ItoR(int to, u32 from) {
	if (to == EAX) {
		write8(0x25); 
	} else {
		write8(0x81); 
		ModRM(3, 0x4, to);
	}
	write32(from); 
}

/* and imm32 to m32 */
void AND32ItoM(u32 to, u32 from) {
	write8(0x81); 
	ModRM(0, 0x4, DISP32);
	write32(to);
	write32(from); 
}

/* and r32 to r32 */
void AND32RtoR(int to, int from) {
	write8(0x21); 
	ModRM(3, from, to);
}

/* and m32 to r32 */
void AND32MtoR(int to, u32 from) {
	write8(0x23); 
	ModRM(0, to, DISP32);
	write32(from); 
}

/* not r32 */
void NOT32R(int from) {
	write8(0xF7); 
	ModRM(3, 2, from);
}

/* neg r32 */
void NEG32R(int from) {
	write8(0xF7); 
	ModRM(3, 3, from);
}

// jump instructions

/* jmp rel8 */
u8*  JMP8(unsigned char to) {
	write8(0xEB); 
	write8(to);
	return x86Ptr - 1;
}

/* jmp rel32 */
u32* JMP32(u32 to) {
	write8(0xE9); 
	write32(to); 
	return (u32*)(x86Ptr - 4);
}

/* jmp r32 */
void JMP32R(int to) {
	write8(0xFF); 
	ModRM(3, 4, to);
}

/* je rel8 */
u8*  JE8(unsigned char to) {
	J8Rel(0x74, to);
}

/* jz rel8 */
u8*  JZ8(unsigned char to) {
	J8Rel(0x74, to); 
}

/* jg rel8 */
u8*  JG8(unsigned char to) { 
	J8Rel(0x7F, to); }

/* jge rel8 */
u8*  JGE8(unsigned char to) { 
	J8Rel(0x7D, to); 
}

/* jl rel8 */
u8*  JL8(unsigned char to) { 
	J8Rel(0x7C, to); 
}

/* jle rel8 */
u8*  JLE8(unsigned char to) { 
	J8Rel(0x7E, to); 
}

/* jne rel8 */
u8*  JNE8(unsigned char to) { 
	J8Rel(0x75, to); 
}

/* jnz rel8 */
u8*  JNZ8(unsigned char to) { 
	J8Rel(0x75, to); 
}

/* jng rel8 */
u8*  JNG8(unsigned char to) { 
	J8Rel(0x7E, to); 
}

/* jnge rel8 */
u8*  JNGE8(unsigned char to) { 
	J8Rel(0x7C, to); 
}

/* jnl rel8 */
u8*  JNL8(unsigned char to) { 
	J8Rel(0x7D, to); 
}

/* jnle rel8 */
u8*  JNLE8(unsigned char to) { 
	J8Rel(0x7F, to); 
}

/* call func */
void CALLFunc(u32 func) {
	CALL32(func - ((u32)x86Ptr + 5));
}

/* call rel32 */
void CALL32(u32 to) {
	write8(0xE8); 
	write32(to); 
}

/* call r32 */
void CALL32R(int to) {
	write8(0xFF);
	ModRM(3, 2, to);
}

// misc instructions

/* cmp imm32 to r32 */
void CMP32ItoR(int to, u32 from) {
	if (to == EAX) {
		write8(0x3D);
	} else {
		write8(0x81);
		ModRM(3, 7, to);
	}
	write32(from); 
}

/* cmp imm32 to m32 */
void CMP32ItoM(u32 to, u32 from) {
	write8(0x81); 
	ModRM(0, 7, DISP32);
	write32(to); 
	write32(from); 
}

/* cmp r32 to r32 */
void CMP32RtoR(int to, int from) {
	write8(0x39);
	ModRM(3, from, to);
}

/* cmp m32 to r32 */
void CMP32MtoR(int to, u32 from) {
	write8(0x3B);
	ModRM(0, to, DISP32);
	write32(from); 
}

/* test imm32 to r32 */
void TEST32ItoR(int to, u32 from) {
	if (to == EAX) {
		write8(0xA9);
	} else {
		write8(0xF7);
		ModRM(3, 0, to);
	}
	write32(from); 
}

/* test r32 to r32 */
void TEST32RtoR(int to, int from) {
	write8(0x85);
	ModRM(3, from, to);
}

/* setl r8 */
void SETL8R(int to) { 
	SET8R(0x9C, to); 
}

/* setb r8 */
void SETB8R(int to) { 
	SET8R(0x92, to); 
}

/* cbw */
void CBW() {
	write16(0x9866); 
}

/* cwd */
void CWD() {
	write8(0x98);
}

/* cdq */
void CDQ() {
	write8(0x99); 
}

/* push r32 */
void PUSH32R(int from) {
	write8(0x50 | from); 
}

/* push m32 */
void PUSH32M(u32 from) {
	write8(0xFF);
	ModRM(0, 6, DISP32);
	write32(from); 
}

/* push imm32 */
void PUSH32I(u32 from) {
	write8(0x68); write32(from); 
}

/* pop r32 */
void POP32R(int from) {
	write8(0x58 | from); 
}

/* pushad */
void PUSHA32() {
	write8(0x60); 
}

/* popad */
void POPA32() {
	write8(0x61); 
}

/* ret */
void RET() {
	write8(0xC3); 
}

/********************/
/* FPU instructions */
/********************/

/* fild m32 to fpu reg stack */
void FILD32(u32 from) {
	write8(0xDB);
	ModRM(0, 0x0, DISP32);
	write32(from); 
}

/* fistp m32 from fpu reg stack */
void FISTP32(u32 from) {
	write8(0xDB);
	ModRM(0, 0x3, DISP32);
	write32(from); 
}

/* fld m32 to fpu reg stack */
void FLD32(u32 from) {
	write8(0xD9);
	ModRM(0, 0x0, DISP32);
	write32(from); 
}

/* fstp m32 from fpu reg stack */
void FSTP32(u32 to) {
	write8(0xD9);
	ModRM(0, 0x3, DISP32);
	write32(to); 
}

//

/* fldcw fpu control word from m16 */
void FLDCW(u32 from) {
	write8(0xD9);
	ModRM(0, 0x5, DISP32);
	write32(from); 
}

/* fnstcw fpu control word to m16 */
void FNSTCW(u32 to) {
	write8(0xD9);
	ModRM(0, 0x7, DISP32);
	write32(to); 
}

//

/* fadd m32 to fpu reg stack */
void FADD32(u32 from) {
	write8(0xD8);
	ModRM(0, 0x0, DISP32);
	write32(from); 
}

/* fsub m32 to fpu reg stack */
void FSUB32(u32 from) {
	write8(0xD8);
	ModRM(0, 0x4, DISP32);
	write32(from); 
}

/* fmul m32 to fpu reg stack */
void FMUL32(u32 from) {
	write8(0xD8);
	ModRM(0, 0x1, DISP32);
	write32(from); 
}

/* fdiv m32 to fpu reg stack */
void FDIV32(u32 from) {
	write8(0xD8);
	ModRM(0, 0x6, DISP32);
	write32(from); 
}

/* fabs fpu reg stack */
void FABS() {
	write16(0xE1D9);
}

/* fsqrt fpu reg stack */
void FSQRT() {
	write16(0xFAD9);
}

/* fchs fpu reg stack */
void FCHS() {
	write16(0xE0D9);
}

/********************/
/* MMX instructions */
/********************/

// r64 = mm

/* movq m64 to r64 */
void MOVQMtoR(int to, u32 from) {
	write16(0x6F0F);
	ModRM(0, to, DISP32);
	write32(from); 
}

/* movq r64 to m64 */
void MOVQRtoM(u32 to, int from) {
	write16(0x7F0F);
	ModRM(0, from, DISP32);
	write32(to); 
}

/* pand r64 to r64 */
void PANDRtoR(int to, int from) {
	write16(0xDB0F);
	ModRM(3, to, from); 
}

/* por r64 to r64 */
void PORRtoR(int to, int from) {
	write16(0xEB0F);
	ModRM(3, to, from); 
}

/* por m64 to r64 */
void PORMtoR(int to, u32 from) {
	write16(0xEB0F);
	ModRM(0, to, DISP32); 
	write32(from);
}

/* pxor r64 to r64 */
void PXORRtoR(int to, int from) {
	write16(0xEF0F);
	ModRM(3, to, from); 
}

/* psllq r64 to r64 */
void PSLLQRtoR(int to, int from) {
	write16(0xF30F);
	ModRM(3, to, from); 
}

/* psllq m64 to r64 */
void PSLLQMtoR(int to, u32 from) {
	write16(0xF30F); 
	ModRM(0, to, DISP32); 
	write32(from);
}

/* psllq imm8 to r64 */
void PSLLQItoR(int to, unsigned char from) {
	write16(0x730F); 
	ModRM(3, 6, to); 
	write8(from); 
}

/* psrlq r64 to r64 */
void PSRLQRtoR(int to, int from) {
	write16(0xD30F); 
	ModRM(3, to, from); 
}

/* psrlq m64 to r64 */
void PSRLQMtoR(int to, u32 from) {
	write16(0xD30F); 
	ModRM(0, to, DISP32); 
	write32(from); 
}

/* psrlq imm8 to r64 */
void PSRLQItoR(int to, unsigned char from) {
	write16(0x730F);
	ModRM(3, 2, to); 
	write8(from); 
}

/* paddusb r64 to r64 */
void PADDUSBRtoR(int to, int from) {
	write16(0xDC0F); 
	ModRM(3, to, from); 
}

/* paddusb m64 to r64 */
void PADDUSBMtoR(int to, u32 from) {
	write16(0xDC0F); 
	ModRM(0, to, DISP32); 
	write32(from); 
}

/* paddusw r64 to r64 */
void PADDUSWRtoR(int to, int from) {
	write16(0xDD0F); 
	ModRM(3, to, from); 
}

/* paddusw m64 to r64 */
void PADDUSWMtoR(int to, u32 from) {
	write16(0xDD0F); 
	ModRM(0, to, DISP32); 
	write32(from); 
}

/* paddb r64 to r64 */
void PADDBRtoR(int to, int from) {
	write16(0xFC0F); 
	ModRM(3, to, from); 
}

/* paddb m64 to r64 */
void PADDBMtoR(int to, u32 from) {
	write16(0xFC0F); 
	ModRM(0, to, DISP32); 
	write32(from); 
}

/* paddw r64 to r64 */
void PADDWRtoR(int to, int from) {
	write16(0xFD0F); 
	ModRM(3, to, from); 
}

/* paddw m64 to r64 */
void PADDWMtoR(int to, u32 from) {
	write16(0xFD0F); 
	ModRM(0, to, DISP32); 
	write32(from); 
}

/* paddd r64 to r64 */
void PADDDRtoR(int to, int from) {
	write16(0xFE0F); 
	ModRM(3, to, from); 
}

/* paddd m64 to r64 */
void PADDDMtoR(int to, u32 from) {
	write16(0xFE0F); 
	ModRM(0, to, DISP32); 
	write32(from); 
}

/* emms */
void EMMS() {
	write16(0x770F);
}