/***************************************************************************
 *
 * All modifications in this file to the original code are
 * (C) Copyright 1992, ..., 2014 the "DOSEMU-Development-Team".
 *
 * for details see file COPYING in the DOSEMU distribution
 *
 *
 *  SIMX86 a Intel 80x86 cpu emulator
 *  Copyright (C) 1997,2001 Alberto Vignani, FIAT Research Center
 *				a.vignani@crf.it
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 * Additional copyright notes:
 *
 * 1. The kernel-level vm86 handling was taken out of the Linux kernel
 *  (linux/arch/i386/kernel/vm86.c). This code originaly was written by
 *  Linus Torvalds with later enhancements by Lutz Molgedey and Hans Lermen.
 *
 ***************************************************************************/

#ifndef _EMU86_CODEGEN_X86_H
#define _EMU86_CODEGEN_X86_H

#include "codegen.h"
#include "trees.h"
#include "vgaemu.h"

#define HOST_ARCH_X86

#define TAILSIZE	7
#define TAILFIX		1

/* If you undefine this, in 16-bit stack mode the high 16 bits of ESP
 * will be zeroed after every push/pop operation. There's a small
 * possibility of breaking some code, you can easily figure out how.
 * For 32-bit stacks, keeping ESP is also a waste of time. */
#undef KEEP_ESP

/////////////////////////////////////////////////////////////////////////////

extern unsigned int VgaAbsBankBase;
extern unsigned int Exec_x86(TNode *G, int ln);
extern unsigned int Exec_x86_fast(TNode *G);

/////////////////////////////////////////////////////////////////////////////

#define STD_WRITE_B	G3M(0x88,0x07,0x90,Cp);
#define STD_WRITE_WL(m)	G3((m)&DATA16?0x078966:0x900789,Cp)

#define GenAddECX(o)	if (((o) > -128) && ((o) < 128)) {\
			G2(0xc183,Cp); G1((o),Cp); } else {\
			G2(0xc181,Cp); G4((o),Cp); }

#define GenLeaECX(o)	if (((o) > -128) && ((o) < 128)) {\
			G2(0x498d,Cp); G1((o),Cp); } else {\
			G2(0x898d,Cp); G4((o),Cp); }

#define GenLeaEDI(o)	if (((o) > -128) && ((o) < 128)) {\
			G2(0x7f8d,Cp); G1((o),Cp); } else {\
			G2(0xbf8d,Cp); G4((o),Cp); }

#define StackMaskEBP	{G2(0x6b23,Cp); G1(Ofs_STACKM,Cp); }

/////////////////////////////////////////////////////////////////////////////

// get all flags and let them on the stack
#define PopPushF(Cp)	if (((Cp)==BaseGenBuf)||((Cp)[-1]!=PUSHF)) \
				G2(0x9c9d,(Cp))

// cld; btl $0xa,EFLAGS(%ebx); jnc 1f; std; 1f:
#define GetDF(Cp)		\
  G4M(CLD,TwoByteESC,0xba,0x63,Cp);	\
  G1(Ofs_EFLAGS,Cp);		\
  G4M(0x0a,JNB_JAE,0x01,STD,Cp);

/////////////////////////////////////////////////////////////////////////////
//

// 'no-jump' version, straight
#define Gen66(mode, Cp) \
	*(Cp)=OPERoverride; Cp+=BTA(BitDATA16, mode)

// 'no-jump' version, tricky (depends on bit position)
#define G2_4(mode, val, Cp) \
	*((int *)(Cp))=(val); Cp+=BT24(BitDATA16, mode)


/////////////////////////////////////////////////////////////////////////////

/* Code generation macros for x86 */
#define GNX(d,s,l)	{memcpy((d),(s),(l));(d)+=(l);}
#define	G1(b,p)		*(p)++=(unsigned char)(b)
#define	G2(w,p)		{unsigned short _w = (w); GNX(p,&_w,2); }
#define	G2M(c,b,p)	{unsigned short _wm = ((b)<<8)|(c);G2(_wm,p);}
#define	G3(l,p)		{unsigned int _l=(l); memcpy((p), &_l, 4);(p)+=3;}
#define	G3M(c,b1,b2,p)	{unsigned int _lm=((b2)<<16)|((b1)<<8)|(c);G3(_lm,p);}
#define	G4(l,p)		{unsigned int _l=(l); GNX(p,&_l,4);}
#define	G4M(c,b1,b2,b3,p) {unsigned int _l=((unsigned)(b3)<<24)|((b2)<<16)|((b1)<<8)|(c);\
			   GNX(p,&_l,4);}
#define	G5(l,p)		{unsigned long long _l=(l); GNX(p,&_l,5);}
#define	G6(l,p)		{unsigned long long _l=(l); GNX(p,&_l,6);}
#define	G7(l,p)		{unsigned long long _l=(l); memcpy((p), &_l, 8);(p)+=7;}
#define	G8(l,p)		{unsigned long long _l=(l); GNX(p,&_l,8);}

/////////////////////////////////////////////////////////////////////////////
//
unsigned char *Fp87_op_x86(unsigned char *CodePtr, int exop, int reg);
void InitGen_x86(void);
void NodeUnlinker(TNode *G);

extern unsigned char TailCode[];

static __inline__ int GoodNode(TNode *G, int mode)
{
	if (G->cs != LONG_CS) {
		/* CS mismatch can confuse relative jump/call */
		e_printf("cs mismatch at %08x: old=%x new=%x\n",
					G->key, G->cs, LONG_CS);
		return 0;
	}
	if (G->mode != mode) {
		/* mode mismatch can be 32/16 or MREALA */
		e_printf("mode mismatch at %08x: old=%x new=%x\n",
					G->key, G->mode, mode);
		return 0;
	}
	return 1;
}

#endif