xref: /dports/games/libretro-hatari/hatari-561c07e/src/uae-cpu/newcpu.c

 /*
  * UAE - The Un*x Amiga Emulator - CPU core
  *
  * MC68000 emulation
  *
  * (c) 1995 Bernd Schmidt
  *
  * Adaptation to Hatari by Thomas Huth
  *
  * This file is distributed under the GNU General Public License, version 2
  * or at your option any later version. Read the file gpl.txt for details.
  */


/* 2007/11/12	[NP]	Add HATARI_TRACE_CPU_DISASM.							*/
/* 2007/11/15	[NP]	In MakeFromSR, writes to m and t0 should be ignored and set to 0 if cpu < 68020 */
/* 2007/11/26	[NP]	We set BusErrorPC in m68k_run_1 instead of M68000_BusError, else the BusErrorPC	*/
/*			will not point to the opcode that generated the bus error.			*/
/*			Huge debug/work on Exceptions 2/3 stack frames, result is more accurate and	*/
/*			allow to pass the very tricky Transbeauce 2 Demo's protection.			*/
/* 2007/11/28	[NP]	Backport DIVS/DIVU cycles exact routines from WinUAE (original work by Jorge	*/
/*			Cwik, pasti@fxatari.com).							*/
/* 2007/12/06	[NP]	The PC stored in the stack frame for the bus error is complex to emulate,	*/
/*			because it doesn't necessarily point to the next instruction after the one that	*/
/*			triggered the bus error. In the case of the Transbeauce 2 Demo, after 		*/
/*			'move.l $0.w,$24.w', PC is incremented of 4 bytes, not 6, and stored in the	*/
/*			stack. Special case to decrement PC of 2 bytes if opcode is '21f8'.		*/
/*			This should be fixed with a real model.						*/
/* 2007/12/07	[NP]	If Trace is enabled and a group 2 exception occurs (such as CHK), the trace	*/
/*			handler should be called after the group 2's handler. If a bus error, address	*/
/*			error or illegal occurs while Trace is enabled, the trace handler should not be	*/
/*			called after this instruction (Transbeauce 2 Demo, Phaleon Demo).		*/
/*			This means that if a CHK is executed while trace bit was set, we must set PC	*/
/*			to CHK handler, turn trace off in the internal SR, but we must still call the	*/
/*			trace handler one last time with the PC set to the CHK's handler (even if	*/
/*			trace mode is internally turned off while processing an exception). Once trace	*/
/*			handler is finished (RTE), we return to the CHK's handler.			*/
/*			This is true for DIV BY 0, CHK, TRAPV and TRAP.					*/
/*			Backport exception_trace() from WinUAE to handle this behaviour	(used in	*/
/*			Transbeauce 2 demo).								*/
/* 2007/12/09	[NP]	'dc.w $a' should not be used to call 'OpCode_SysInit' but should give an illegal*/
/*			instruction (Transbeauce 2 demo).						*/
/*			Instead of always replacing the illegal instructions $8, $a and $c by the	*/
/*			3 functions required for HD emulation, we now do it in cart.c only if the	*/
/*			built-in cartridge image is loaded.						*/
/*			YEAH! Hatari is now the first emulator to pass the Transbeauce 2 protection :)	*/
/* 2007/12/18	[NP]	More precise timings for HBL, VBL and MFP interrupts. On ST, these interrupts	*/
/*			are taking 56 cycles instead of the 44 cycles in the 68000's documentation.	*/
/* 2007/12/24	[NP]	If an interrupt (HBL, VBL) is pending after instruction 'n' was processed, the	*/
/*			exception should be called before instr. 'n+1' is processed, not after (else the*/
/*			interrupt's handler is delayed by one 68000's instruction, which could break	*/
/*			some demos with too strict timings) (ACF's Demo Main Menu).			*/
/*			We call the interrupt if ( SPCFLAG_INT | SPCFLAG_DOINT ) is set, not only if	*/
/*			SPCFLAG_DOINT is set (as it was already the case when handling 'STOP').		*/
/* 2007/12/25	[NP]	FIXME When handling exceptions' cycles, using nr >= 64 to determine if this is	*/
/*			an MFP exception could be wrong if the MFP VR was set to another value than the	*/
/*			default $40 (this could be a problem with programs requiring a precise cycles	*/
/*			calculation while changing VR, but no such programs were encountered so far).	*/
/*			-> FIXED, see 2008/10/05							*/
/* 2008/04/17	[NP]	In m68k_run_1/m68k_run_2, add the wait state cycles before testing if content	*/
/*			of PendingInterruptCount is <= 0 (else the int could happen a few cycles earlier*/
/*			than expected in some rare cases (reading $fffa21 in BIG Demo Screen 1)).	*/
/* 2008/09/14	[NP]	Add the value of the new PC in the exception's log.				*/
/* 2008/09/14	[NP]	Correct cycles for TRAP are 34 not 38 (4 more cycles were counted because cpuemu*/
/*			returns 4 and Exception() adds 34) (Phaleon / Illusion Demo by Next).		*/
/*			FIXME : Others exception cycles may be wrong too.				*/
/* 2008/10/05	[NP]	Add a parameter 'ExceptionSource' to Exception(). This allows to know the source*/
/*			of the exception (video, mfp, cpu) and properly handle MFP interrupts. Since	*/
/*			it's possible to change the vector base in $fffa17, MFP int vectors can overlap	*/
/*			the 'normal' 68000 ones and the exception number is not enough to decide.	*/
/*			We need ExceptionSource to remove the ambiguity.				*/
/*			Fix High Fidelity Dreams by Aura which sets MFP vector base to $c0 instead of	*/
/*			$100. In that case, timer B int becomes exception nr 56 and conflicts with the	*/
/*			'MMU config error' exception, which takes 4 cycles instead of 56 cycles for MFP.*/
/* 2008/11/18	[NP]	In 'do_specialties()', when the cpu is in the STOP state, we must test all	*/
/*			possible int handlers while PendingInterruptCount <= 0 without increasing the	*/
/*			cpu cycle counter. In the case where both an MFP int and an HBL occur at the	*/
/*			same time for example, the HBL was delayed by 4 cycles if no MFP exception	*/
/*			was triggered, which was wrong (this happened mainly with the TOS timer D that	*/
/*			expires very often). Such precision is required for very recent hardscroll	*/
/*			techniques that use 'stop' to stay in sync with the video shifter.		*/
/* 2008/11/23	[NP]	In 'do_specialties()', when in STOP state, we must first test for a pending	*/
/*			interrupt that would exit the STOP state immediately, without doing a 'while'	*/
/*			loop until 'SPCFLAG_INT' or 'SPCFLAG_DOINT' are set.				*/
/* 2008/11/29	[NP]	Call 'InterruptAddJitter()' when a video interrupt happens to precisely emulate */
/*			the jitter happening on the Atari (see video.c for the jitter patterns).	*/
/*			FIXME : Pattern is not always correct when handling pending interrupt in STOP	*/
/*			state, but this should be harmless as no program has been found using this.	*/
/* 2008/12/05	[NP]	On Atari it takes 56 cycles to process an interrupt. During that time, a higher	*/
/*			level interrupt could happen and we must execute it before the previous int	*/
/*			(see m68k_run_1()).								*/
/*			This is the case for the VBL which can interrupt the last HBL of a screen	*/
/*			(end of line 312) at various point (from 0 to 8 cycles).			*/
/*			This fixes the fullscreen tunnel in Suretrip 49% by Checkpoint, which uses a	*/
/*			really buggy vbl/hbl combination, even on a real ST. Also fixes sample sound	*/
/*			in Swedish New Year's TCB screen.						*/
/* 2008/12/11	[NP]	Extract interrupt handling from do_specialties() in do_specialties_interrupt()	*/
/*			and factorize some code. In m68k_run_1 when testing for multiple interrupts at	*/
/*			the same time, call do_specialties_interrupt() to check only the special flags	*/
/*			related to interrupts (MFP and video) (else, this caused problem when the TRACE	*/
/*			flag was set).									*/
/* 2008/12/14	[NP]	In m68k_run_1(), we should check for simultaneous ints only if the cpu is not	*/
/*			in the STOP state after the last instruction was executed. Else, the call to	*/
/*			do_specialties_interrupt() could acknowledge the interrupt and we would never	*/
/*			exit the STOP state in do_specialties() just after (the problem can happen if	*/
/*			the TOS timer D expires just at the same time as the STOP instruction).		*/
/*			Fix regression since 2008/12/11 in the hidden screen from ULM in Oh Crickey...	*/
/* 2008/12/20	[NP]	In m68k_run_1(), when checking interrupts and STOP mode, we should test		*/
/*			PendingInterruptCount before regs.spcflags to have a faster evaluation of the	*/
/*			'while' condition (PendingInterruptCount <= 0 is true less often than STOP==0)	*/
/* 2011/04/29	[NP]	In Exception(), check the new PC is not on odd address ; raise an address error	*/
/*			exception if it's the case.							*/
/* 2012/09/01	[NP]	Add a special case to correct the stacked PC when a bus error happens during	*/
/*			a movem (fix the game Blood Money).						*/
/* 2013/03/16	[NP]	In refill_prefetch(), reload only one new word in regs.prefetch if low word is	*/
/*			still valid : low word goes to high word and we reload only low word		*/
/*			(fix EOR/ADD self modified code in the protection for the game Damocles).	*/
/* 2013/04/11	[NP]	In Exception(), call MFP_ProcessIACK after 12 cycles to update the MFP's vector	*/
/*			number used for the exception (see mfp.c).					*/
/* 2013/05/03	[NP]	In Exception(), handle IACK for HBL and VBL interrupts too, allowing pending bit*/
/*			to be set twice during an active video interrupt (correct fix for Super Monaco	*/
/*			GP, Super Hang On, Monster Business, European Demo's Intro, BBC Menu 52).	*/
/* 2014/02/22	[NP]	In Exception(), call valid_address() before reading the opcode at BusErrorPC,	*/
/*			else this will cause an unwanted "double bus error" ("Union Demo" loader).	*/
/* 2014/02/22	[NP]	In refill_prefetch(), use get_word() instead of do_get_mem_word() to generate	*/
/*			a bus error when trying to read from an invalid region.				*/
/* 2014/03/18	[NP]	In Exception(), add a specific case to restore the dest part of a "move" after	*/
/*			it was overwritten during a bus error (fix the game Dragon Flight).		*/
/* 2014/04/06	[NP]	In Exception(), add a special case for last_addr_for_exception_3 stored in the	*/
/*			stack after a bus error (fix the game Batman The Movie).			*/
/* 2014/09/07	[NP]	In m68k_run_1(), if get_iword_prefetch() triggers a bus error, we must call the	*/
/*			bus error immediately and fetch the correct opcode for the bus error handler	*/
/*			(fix Blood Money on Superior 65, PC=4e664e66 after RTS).			*/
/* 2014/09/07	[NP]	For address error, store if the access was in cpu space or data space and fix	*/
/*			the exception stack frame accordingly (fix Blood Money on Superior 65,		*/
/*			PC=4e664e66 after RTS)								*/

const char NewCpu_fileid[] = "Hatari newcpu.c : " __DATE__ " " __TIME__;

#include "sysdeps.h"
#include "hatari-glue.h"
#include "maccess.h"
#include "memory.h"
#include "newcpu.h"
#include "main.h"
#include "m68000.h"
#include "cycInt.h"
#include "mfp.h"
#include "tos.h"
#include "vdi.h"
#include "cart.h"
#include "dialog.h"
#include "bios.h"
#include "xbios.h"
#include "screen.h"
#include "video.h"
#include "options.h"
#include "dsp.h"
#include "log.h"
#include "debugui.h"
#include "debugcpu.h"
#include "68kDisass.h"

#ifdef HAVE_CAPSIMAGE
#if CAPSIMAGE_VERSION == 5
#include <caps5/CapsLibAll.h>
#endif
#endif

//#define DEBUG_PREFETCH

struct flag_struct regflags;

/* Opcode of faulting instruction */
uae_u16 last_op_for_exception_3;
/* PC at fault time */
uaecptr last_addr_for_exception_3;
/* Address that generated the exception */
uaecptr last_fault_for_exception_3;
/* instruction (1) or data (0) access */
int last_instructionaccess_for_exception_3;

const int areg_byteinc[] = { 1,1,1,1,1,1,1,2 };
const int imm8_table[] = { 8,1,2,3,4,5,6,7 };

int movem_index1[256];
int movem_index2[256];
int movem_next[256];

int fpp_movem_index1[256];
int fpp_movem_index2[256];
int fpp_movem_next[256];

cpuop_func *cpufunctbl[65536];

int OpcodeFamily;
int BusCyclePenalty = 0;

#define COUNT_INSTRS 0

#if COUNT_INSTRS
static unsigned long int instrcount[65536];
static uae_u16 opcodenums[65536];

static int compfn (const void *el1, const void *el2)
{
    return instrcount[*(const uae_u16 *)el1] < instrcount[*(const uae_u16 *)el2];
}

static char *icountfilename (void)
{
    char *name = getenv ("INSNCOUNT");
    if (name)
	return name;
    return COUNT_INSTRS == 2 ? "frequent.68k" : "insncount";
}

void dump_counts (void)
{
    FILE *f = fopen (icountfilename (), "w");
    unsigned long int total;
    int i;

    write_log ("Writing instruction count file...\n");
    for (i = 0; i < 65536; i++) {
	opcodenums[i] = i;
	total += instrcount[i];
    }
    qsort (opcodenums, 65536, sizeof(uae_u16), compfn);

    fprintf (f, "Total: %lu\n", total);
    for (i=0; i < 65536; i++) {
	unsigned long int cnt = instrcount[opcodenums[i]];
	struct instr *dp;
	struct mnemolookup *lookup;
	if (!cnt)
	    break;
	dp = table68k + opcodenums[i];
	for (lookup = lookuptab;lookup->mnemo != dp->mnemo; lookup++)
	    ;
	fprintf (f, "%04x: %lu %s\n", opcodenums[i], cnt, lookup->name);
    }
    fclose (f);
}
#else
void dump_counts (void)
{
}
#endif


static unsigned long op_illg_1 (uae_u32 opcode) REGPARAM;

static unsigned long REGPARAM2 op_illg_1 (uae_u32 opcode)
{
    op_illg (opcode);
    return 4;
}


void build_cpufunctbl(void)
{
    int i;
    unsigned long opcode;
    const struct cputbl *tbl = (currprefs.cpu_level == 4 ? op_smalltbl_0_ff
			      : currprefs.cpu_level == 3 ? op_smalltbl_1_ff
			      : currprefs.cpu_level == 2 ? op_smalltbl_2_ff
			      : currprefs.cpu_level == 1 ? op_smalltbl_3_ff
			      : ! currprefs.cpu_compatible ? op_smalltbl_4_ff
			      : op_smalltbl_5_ff);

    Log_Printf(LOG_DEBUG, "Building CPU function table (%d %d %d).\n",
	           currprefs.cpu_level, currprefs.cpu_compatible, currprefs.address_space_24);

    for (opcode = 0; opcode < 65536; opcode++)
	cpufunctbl[opcode] = op_illg_1;
    for (i = 0; tbl[i].handler != NULL; i++) {
	if (! tbl[i].specific)
	    cpufunctbl[tbl[i].opcode] = tbl[i].handler;
    }
    for (opcode = 0; opcode < 65536; opcode++) {
	cpuop_func *f;

	if (table68k[opcode].mnemo == i_ILLG || table68k[opcode].clev > currprefs.cpu_level)
	    continue;

	if (table68k[opcode].handler != -1) {
	    f = cpufunctbl[table68k[opcode].handler];
	    if (f == op_illg_1)
		abort();
	    cpufunctbl[opcode] = f;
	}
    }
    for (i = 0; tbl[i].handler != NULL; i++) {
	if (tbl[i].specific)
	    cpufunctbl[tbl[i].opcode] = tbl[i].handler;
    }
}



void init_m68k (void)
{
    int i;

    for (i = 0 ; i < 256 ; i++) {
	int j;
	for (j = 0 ; j < 8 ; j++) {
		if (i & (1 << j)) break;
	}
	movem_index1[i] = j;
	movem_index2[i] = 7-j;
	movem_next[i] = i & (~(1 << j));
    }
    for (i = 0 ; i < 256 ; i++) {
	int j;
	for (j = 7 ; j >= 0 ; j--) {
		if (i & (1 << j)) break;
	}
	fpp_movem_index1[i] = 7-j;
	fpp_movem_index2[i] = j;
	fpp_movem_next[i] = i & (~(1 << j));
    }
#if COUNT_INSTRS
    {
	FILE *f = fopen (icountfilename (), "r");
	memset (instrcount, 0, sizeof instrcount);
	if (f) {
	    uae_u32 opcode, count, total;
	    char name[20];
	    write_log ("Reading instruction count file...\n");
	    fscanf (f, "Total: %lu\n", &total);
	    while (fscanf (f, "%lx: %lu %s\n", &opcode, &count, name) == 3) {
		instrcount[opcode] = count;
	    }
	    fclose(f);
	}
    }
#endif
    write_log ("Building CPU table for configuration: 68");
    if (currprefs.address_space_24 && currprefs.cpu_level > 1)
        write_log ("EC");
    switch (currprefs.cpu_level) {
    case 1:
        write_log ("010");
        break;
    case 2:
        write_log ("020");
        break;
    case 3:
        write_log ("020/881");
        break;
    case 4:
        /* Who is going to miss the MMU anyway...? :-)  */
        write_log ("040");
        break;
    default:
        write_log ("000");
        break;
    }
    if (currprefs.cpu_compatible)
        write_log (" (compatible mode)");
    write_log ("\n");

    read_table68k ();
    do_merges ();

    Log_Printf(LOG_DEBUG, "%d CPU functions\n", nr_cpuop_funcs);

    build_cpufunctbl ();
}


/* not used ATM:
static struct regstruct regs_backup[16];
static int backup_pointer = 0;
struct regstruct lastint_regs;
int lastint_no;
*/
struct regstruct regs;
static long int m68kpc_offset;


#define get_ibyte_1(o) get_byte(regs.pc + (regs.pc_p - regs.pc_oldp) + (o) + 1)
#define get_iword_1(o) get_word(regs.pc + (regs.pc_p - regs.pc_oldp) + (o))
#define get_ilong_1(o) get_long(regs.pc + (regs.pc_p - regs.pc_oldp) + (o))

uae_s32 ShowEA (FILE *f, int reg, amodes mode, wordsizes size, char *buf)
{
    uae_u16 dp;
    uae_s8 disp8;
    uae_s16 disp16;
    int r;
    uae_u32 dispreg;
    uaecptr addr;
    uae_s32 offset = 0;
    char buffer[80];

    switch (mode){
     case Dreg:
	sprintf (buffer,"D%d", reg);
	break;
     case Areg:
	sprintf (buffer,"A%d", reg);
	break;
     case Aind:
	sprintf (buffer,"(A%d)", reg);
	break;
     case Aipi:
	sprintf (buffer,"(A%d)+", reg);
	break;
     case Apdi:
	sprintf (buffer,"-(A%d)", reg);
	break;
     case Ad16:
	disp16 = get_iword_1 (m68kpc_offset); m68kpc_offset += 2;
	addr = m68k_areg(regs,reg) + (uae_s16)disp16;
	sprintf (buffer,"(A%d,$%04x) == $%08lx", reg, disp16 & 0xffff,
					(unsigned long)addr);
	break;
     case Ad8r:
	dp = get_iword_1 (m68kpc_offset); m68kpc_offset += 2;
	disp8 = dp & 0xFF;
	r = (dp & 0x7000) >> 12;
	dispreg = dp & 0x8000 ? m68k_areg(regs,r) : m68k_dreg(regs,r);
	if (!(dp & 0x800)) dispreg = (uae_s32)(uae_s16)(dispreg);
	dispreg <<= (dp >> 9) & 3;

	if (dp & 0x100) {
	    uae_s32 outer = 0, disp = 0;
	    uae_s32 base = m68k_areg(regs,reg);
	    char name[10];
	    sprintf (name,"A%d, ",reg);
	    if (dp & 0x80) { base = 0; name[0] = 0; }
	    if (dp & 0x40) dispreg = 0;
	    if ((dp & 0x30) == 0x20) { disp = (uae_s32)(uae_s16)get_iword_1 (m68kpc_offset); m68kpc_offset += 2; }
	    if ((dp & 0x30) == 0x30) { disp = get_ilong_1 (m68kpc_offset); m68kpc_offset += 4; }
	    base += disp;

	    if ((dp & 0x3) == 0x2) { outer = (uae_s32)(uae_s16)get_iword_1 (m68kpc_offset); m68kpc_offset += 2; }
	    if ((dp & 0x3) == 0x3) { outer = get_ilong_1 (m68kpc_offset); m68kpc_offset += 4; }

	    if (!(dp & 4)) base += dispreg;
	    if (dp & 3) base = get_long (base);
	    if (dp & 4) base += dispreg;

	    addr = base + outer;
	    sprintf (buffer,"(%s%c%d.%c*%d+%ld)+%ld == $%08lx", name,
		    dp & 0x8000 ? 'A' : 'D', (int)r, dp & 0x800 ? 'L' : 'W',
		    1 << ((dp >> 9) & 3),
		    (long)disp, (long)outer, (unsigned long)addr);
	} else {
	  addr = m68k_areg(regs,reg) + (uae_s32)((uae_s8)disp8) + dispreg;
	  sprintf (buffer,"(A%d, %c%d.%c*%d, $%02x) == $%08lx", reg,
	       dp & 0x8000 ? 'A' : 'D', (int)r, dp & 0x800 ? 'L' : 'W',
	       1 << ((dp >> 9) & 3), disp8,
	       (unsigned long)addr);
	}
	break;
     case PC16:
	addr = m68k_getpc () + m68kpc_offset;
	disp16 = get_iword_1 (m68kpc_offset); m68kpc_offset += 2;
	addr += (uae_s16)disp16;
	sprintf (buffer,"(PC,$%04x) == $%08lx", disp16 & 0xffff,(unsigned long)addr);
	break;
     case PC8r:
	addr = m68k_getpc () + m68kpc_offset;
	dp = get_iword_1 (m68kpc_offset); m68kpc_offset += 2;
	disp8 = dp & 0xFF;
	r = (dp & 0x7000) >> 12;
	dispreg = dp & 0x8000 ? m68k_areg(regs,r) : m68k_dreg(regs,r);
	if (!(dp & 0x800)) dispreg = (uae_s32)(uae_s16)(dispreg);
	dispreg <<= (dp >> 9) & 3;

	if (dp & 0x100) {
	    uae_s32 outer = 0,disp = 0;
	    uae_s32 base = addr;
	    char name[10];
	    sprintf (name,"PC, ");
	    if (dp & 0x80) { base = 0; name[0] = 0; }
	    if (dp & 0x40) dispreg = 0;
	    if ((dp & 0x30) == 0x20) { disp = (uae_s32)(uae_s16)get_iword_1 (m68kpc_offset); m68kpc_offset += 2; }
	    if ((dp & 0x30) == 0x30) { disp = get_ilong_1 (m68kpc_offset); m68kpc_offset += 4; }
	    base += disp;

	    if ((dp & 0x3) == 0x2) { outer = (uae_s32)(uae_s16)get_iword_1 (m68kpc_offset); m68kpc_offset += 2; }
	    if ((dp & 0x3) == 0x3) { outer = get_ilong_1 (m68kpc_offset); m68kpc_offset += 4; }

	    if (!(dp & 4)) base += dispreg;
	    if (dp & 3) base = get_long (base);
	    if (dp & 4) base += dispreg;

	    addr = base + outer;
	    sprintf (buffer,"(%s%c%d.%c*%d+%ld)+%ld == $%08lx", name,
		    dp & 0x8000 ? 'A' : 'D', (int)r, dp & 0x800 ? 'L' : 'W',
		    1 << ((dp >> 9) & 3),
		    (long)disp, (long)outer, (unsigned long)addr);
	} else {
	  addr += (uae_s32)((uae_s8)disp8) + dispreg;
	  sprintf (buffer,"(PC, %c%d.%c*%d, $%02x) == $%08lx", dp & 0x8000 ? 'A' : 'D',
		(int)r, dp & 0x800 ? 'L' : 'W',  1 << ((dp >> 9) & 3),
		disp8, (unsigned long)addr);
	}
	break;
     case absw:
	sprintf (buffer,"$%08lx", (unsigned long)(uae_s32)(uae_s16)get_iword_1 (m68kpc_offset));
	m68kpc_offset += 2;
	break;
     case absl:
	sprintf (buffer,"$%08lx", (unsigned long)get_ilong_1 (m68kpc_offset));
	m68kpc_offset += 4;
	break;
     case imm:
	switch (size){
	 case sz_byte:
	    sprintf (buffer,"#$%02x", (unsigned int)(get_iword_1 (m68kpc_offset) & 0xff));
	    m68kpc_offset += 2;
	    break;
	 case sz_word:
	    sprintf (buffer,"#$%04x", (unsigned int)(get_iword_1 (m68kpc_offset) & 0xffff));
	    m68kpc_offset += 2;
	    break;
	 case sz_long:
	    sprintf (buffer,"#$%08lx", (unsigned long)(get_ilong_1 (m68kpc_offset)));
	    m68kpc_offset += 4;
	    break;
	 default:
	    break;
	}
	break;
     case imm0:
	offset = (uae_s32)(uae_s8)get_iword_1 (m68kpc_offset);
	m68kpc_offset += 2;
	sprintf (buffer,"#$%02x", (unsigned int)(offset & 0xff));
	break;
     case imm1:
	offset = (uae_s32)(uae_s16)get_iword_1 (m68kpc_offset);
	m68kpc_offset += 2;
	sprintf (buffer,"#$%04x", (unsigned int)(offset & 0xffff));
	break;
     case imm2:
	offset = (uae_s32)get_ilong_1 (m68kpc_offset);
	m68kpc_offset += 4;
	sprintf (buffer,"#$%08lx", (unsigned long)offset);
	break;
     case immi:
	offset = (uae_s32)(uae_s8)(reg & 0xff);
	sprintf (buffer,"#$%08lx", (unsigned long)offset);
	break;
     default:
	break;
    }
    if (buf == 0)
	fprintf (f, "%s", buffer);
    else
	strcat (buf, buffer);
    return offset;
}


/* The plan is that this will take over the job of exception 3 handling -
 * the CPU emulation functions will just do a longjmp to m68k_go whenever
 * they hit an odd address. */
#if 0
static int verify_ea (int reg, amodes mode, wordsizes size, uae_u32 *val)
{
    uae_u16 dp;
    uae_s8 disp8;
    uae_s16 disp16;
    int r;
    uae_u32 dispreg;
    uaecptr addr;
    /*uae_s32 offset = 0;*/

    switch (mode){
     case Dreg:
	*val = m68k_dreg (regs, reg);
	return 1;
     case Areg:
	*val = m68k_areg (regs, reg);
	return 1;

     case Aind:
     case Aipi:
	addr = m68k_areg (regs, reg);
	break;
     case Apdi:
	addr = m68k_areg (regs, reg);
	break;
     case Ad16:
	disp16 = get_iword_1 (m68kpc_offset); m68kpc_offset += 2;
	addr = m68k_areg(regs,reg) + (uae_s16)disp16;
	break;
     case Ad8r:
	addr = m68k_areg (regs, reg);
     d8r_common:
	dp = get_iword_1 (m68kpc_offset); m68kpc_offset += 2;
	disp8 = dp & 0xFF;
	r = (dp & 0x7000) >> 12;
	dispreg = dp & 0x8000 ? m68k_areg(regs,r) : m68k_dreg(regs,r);
	if (!(dp & 0x800)) dispreg = (uae_s32)(uae_s16)(dispreg);
	dispreg <<= (dp >> 9) & 3;

	if (dp & 0x100) {
	    uae_s32 outer = 0, disp = 0;
	    uae_s32 base = addr;
	    if (dp & 0x80) base = 0;
	    if (dp & 0x40) dispreg = 0;
	    if ((dp & 0x30) == 0x20) { disp = (uae_s32)(uae_s16)get_iword_1 (m68kpc_offset); m68kpc_offset += 2; }
	    if ((dp & 0x30) == 0x30) { disp = get_ilong_1 (m68kpc_offset); m68kpc_offset += 4; }
	    base += disp;

	    if ((dp & 0x3) == 0x2) { outer = (uae_s32)(uae_s16)get_iword_1 (m68kpc_offset); m68kpc_offset += 2; }
	    if ((dp & 0x3) == 0x3) { outer = get_ilong_1 (m68kpc_offset); m68kpc_offset += 4; }

	    if (!(dp & 4)) base += dispreg;
	    if (dp & 3) base = get_long (base);
	    if (dp & 4) base += dispreg;

	    addr = base + outer;
	} else {
	  addr += (uae_s32)((uae_s8)disp8) + dispreg;
	}
	break;
     case PC16:
	addr = m68k_getpc () + m68kpc_offset;
	disp16 = get_iword_1 (m68kpc_offset); m68kpc_offset += 2;
	addr += (uae_s16)disp16;
	break;
     case PC8r:
	addr = m68k_getpc () + m68kpc_offset;
	goto d8r_common;
     case absw:
	addr = (uae_s32)(uae_s16)get_iword_1 (m68kpc_offset);
	m68kpc_offset += 2;
	break;
     case absl:
	addr = get_ilong_1 (m68kpc_offset);
	m68kpc_offset += 4;
	break;
     case imm:
	switch (size){
	 case sz_byte:
	    *val = get_iword_1 (m68kpc_offset) & 0xff;
	    m68kpc_offset += 2;
	    break;
	 case sz_word:
	    *val = get_iword_1 (m68kpc_offset) & 0xffff;
	    m68kpc_offset += 2;
	    break;
	 case sz_long:
	    *val = get_ilong_1 (m68kpc_offset);
	    m68kpc_offset += 4;
	    break;
	 default:
	    break;
	}
	return 1;
     case imm0:
	*val = (uae_s32)(uae_s8)get_iword_1 (m68kpc_offset);
	m68kpc_offset += 2;
	return 1;
     case imm1:
	*val = (uae_s32)(uae_s16)get_iword_1 (m68kpc_offset);
	m68kpc_offset += 2;
	return 1;
     case imm2:
	*val = get_ilong_1 (m68kpc_offset);
	m68kpc_offset += 4;
	return 1;
     case immi:
	*val = (uae_s32)(uae_s8)(reg & 0xff);
	return 1;
     default:
	addr = 0;
	break;
    }
    if ((addr & 1) == 0)
	return 1;

    last_addr_for_exception_3 = m68k_getpc () + m68kpc_offset;
    last_fault_for_exception_3 = addr;
    return 0;
}
#endif


uae_u32 get_disp_ea_020 (uae_u32 base, uae_u32 dp)
{
    int reg = (dp >> 12) & 15;
    uae_s32 regd = regs.regs[reg];
    if ((dp & 0x800) == 0)
	regd = (uae_s32)(uae_s16)regd;
    regd <<= (dp >> 9) & 3;
    if (dp & 0x100) {
	uae_s32 outer = 0;
	if (dp & 0x80) base = 0;
	if (dp & 0x40) regd = 0;

	if ((dp & 0x30) == 0x20) base += (uae_s32)(uae_s16)next_iword();
	if ((dp & 0x30) == 0x30) base += next_ilong();

	if ((dp & 0x3) == 0x2) outer = (uae_s32)(uae_s16)next_iword();
	if ((dp & 0x3) == 0x3) outer = next_ilong();

	if ((dp & 0x4) == 0) base += regd;
	if (dp & 0x3) base = get_long (base);
	if (dp & 0x4) base += regd;

	return base + outer;
    } else {
	return base + (uae_s32)((uae_s8)dp) + regd;
    }
}

uae_u32 get_disp_ea_000 (uae_u32 base, uae_u32 dp)
{
    int reg = (dp >> 12) & 15;
    uae_s32 regd = regs.regs[reg];
#if 1
    if ((dp & 0x800) == 0)
	regd = (uae_s32)(uae_s16)regd;
    return base + (uae_s8)dp + regd;
#else
    /* Branch-free code... benchmark this again now that
     * things are no longer inline.  */
    uae_s32 regd16;
    uae_u32 mask;
    mask = ((dp & 0x800) >> 11) - 1;
    regd16 = (uae_s32)(uae_s16)regd;
    regd16 &= mask;
    mask = ~mask;
    base += (uae_s8)dp;
    regd &= mask;
    regd |= regd16;
    return base + regd;
#endif
}


/* Create the Status Register from the flags */
void MakeSR (void)
{
#if 0
    assert((regs.t1 & 1) == regs.t1);
    assert((regs.t0 & 1) == regs.t0);
    assert((regs.s & 1) == regs.s);
    assert((regs.m & 1) == regs.m);
    assert((XFLG & 1) == XFLG);
    assert((NFLG & 1) == NFLG);
    assert((ZFLG & 1) == ZFLG);
    assert((VFLG & 1) == VFLG);
    assert((CFLG & 1) == CFLG);
#endif
    regs.sr = ((regs.t1 << 15) | (regs.t0 << 14)
	       | (regs.s << 13) | (regs.m << 12) | (regs.intmask << 8)
	       | (GET_XFLG << 4) | (GET_NFLG << 3) | (GET_ZFLG << 2) | (GET_VFLG << 1)
	       | GET_CFLG);
}


/* Set up the flags from Status Register */
void MakeFromSR (void)
{
    int oldm = regs.m;
    int olds = regs.s;

    regs.t1 = (regs.sr >> 15) & 1;
    regs.t0 = (regs.sr >> 14) & 1;
    regs.s = (regs.sr >> 13) & 1;
    regs.m = (regs.sr >> 12) & 1;
    regs.intmask = (regs.sr >> 8) & 7;
    SET_XFLG ((regs.sr >> 4) & 1);
    SET_NFLG ((regs.sr >> 3) & 1);
    SET_ZFLG ((regs.sr >> 2) & 1);
    SET_VFLG ((regs.sr >> 1) & 1);
    SET_CFLG (regs.sr & 1);
    if (currprefs.cpu_level >= 2) {
	if (olds != regs.s) {
	    if (olds) {
		if (oldm)
		    regs.msp = m68k_areg(regs, 7);
		else
		    regs.isp = m68k_areg(regs, 7);
		m68k_areg(regs, 7) = regs.usp;
	    } else {
		regs.usp = m68k_areg(regs, 7);
		m68k_areg(regs, 7) = regs.m ? regs.msp : regs.isp;
	    }
	} else if (olds && oldm != regs.m) {
	    if (oldm) {
		regs.msp = m68k_areg(regs, 7);
		m68k_areg(regs, 7) = regs.isp;
	    } else {
		regs.isp = m68k_areg(regs, 7);
		m68k_areg(regs, 7) = regs.msp;
	    }
	}
    } else {
	/* [NP] If cpu < 68020, m and t0 are ignored and should be set to 0 */
	regs.t0 = 0;
	regs.m = 0;

	if (olds != regs.s) {
	    if (olds) {
		regs.isp = m68k_areg(regs, 7);
		m68k_areg(regs, 7) = regs.usp;
	    } else {
		regs.usp = m68k_areg(regs, 7);
		m68k_areg(regs, 7) = regs.isp;
	    }
	}
    }

    /* Pending interrupts can occur again after a write to the SR: */
    set_special (SPCFLAG_DOINT);
    if (regs.t1 || regs.t0)
	set_special (SPCFLAG_TRACE);
    else
	/* Keep SPCFLAG_DOTRACE, we still want a trace exception for
	   SR-modifying instructions (including STOP).  */
	unset_special (SPCFLAG_TRACE);
}


static void exception_trace (int nr)
{
    unset_special (SPCFLAG_TRACE | SPCFLAG_DOTRACE);
    if (regs.t1 && !regs.t0) {
        /* trace stays pending if exception is div by zero, chk,
         * trapv or trap #x
         */
        if (nr == 5 || nr == 6 || nr == 7 || (nr >= 32 && nr <= 47))
            set_special (SPCFLAG_DOTRACE);
    }
    regs.t1 = regs.t0 = regs.m = 0;
}


/*
 * Compute the number of jitter cycles to add when a video interrupt occurs
 * (this is specific to the Atari ST)
 */
static void InterruptAddJitter (int Level , int Pending)
{
    int cycles = 0;

    if ( Level == 2 )				/* HBL */
      {
        if ( Pending )
	  cycles = HblJitterArrayPending[ HblJitterIndex ];
	else
	  cycles = HblJitterArray[ HblJitterIndex ];
      }

    else if ( Level == 4 )			/* VBL */
      {
        if ( Pending )
	  cycles = VblJitterArrayPending[ VblJitterIndex ];
	else
	  cycles = VblJitterArray[ VblJitterIndex ];
      }

//fprintf ( stderr , "jitter %d\n" , cycles );
//cycles=0;
    if ( cycles > 0 )				/* no need to call M68000_AddCycles if cycles == 0 */
      M68000_AddCycles ( cycles );
}


/* Handle exceptions. We need a special case to handle MFP exceptions */
/* on Atari ST, because it's possible to change the MFP's vector base */
/* and get a conflict with 'normal' cpu exceptions. */
void Exception(int nr, uaecptr oldpc, int ExceptionSource)
{
    uae_u32 currpc = m68k_getpc () , newpc;

    /*if( nr>=2 && nr<10 )  fprintf(stderr,"Exception (-> %i bombs)!\n",nr);*/

    /* Pending bits / vector number can change before the end of the IACK sequence. */
    /* We need to handle MFP and HBL/VBL cases for this. */
    if ( ExceptionSource == M68000_EXC_SRC_INT_MFP )
    {
        M68000_AddCycles ( CPU_IACK_CYCLES_MFP );
	CPU_IACK = true;
        while ( ( PendingInterruptCount <= 0 ) && ( PendingInterruptFunction ) )
            CALL_VAR(PendingInterruptFunction);
        nr = MFP_ProcessIACK ( nr );
	CPU_IACK = false;
    }
    else if ( ( ExceptionSource == M68000_EXC_SRC_AUTOVEC ) && ( ( nr == 26 ) || ( nr == 28 ) ) )
    {
        M68000_AddCycles ( CPU_IACK_CYCLES_VIDEO );
	CPU_IACK = true;
        while ( ( PendingInterruptCount <= 0 ) && ( PendingInterruptFunction ) )
            CALL_VAR(PendingInterruptFunction);
        if ( MFP_UpdateNeeded == true )
            MFP_UpdateIRQ ( 0 );					/* update MFP's state if some internal timers related to MFP expired */
        pendingInterrupts &= ~( 1 << ( nr - 24 ) );			/* clear HBL or VBL pending bit */
	CPU_IACK = false;
    }


    if (ExceptionSource == M68000_EXC_SRC_CPU)
      {
        if (nr == 0x22)
        {
          /* Intercept VDI & AES exceptions (Trap #2) */
          if(bVdiAesIntercept && VDI_AES_Entry())
          {
            /* Set 'PC' to address of 'VDI_OPCODE' illegal instruction.
             * This will call OpCode_VDI() after completion of Trap call!
             * This is used to modify specific VDI return vectors contents.
	     */
            VDI_OldPC = currpc;
            currpc = CART_VDI_OPCODE_ADDR;
          }
        }
        else if (nr == 0x2d)
        {
          /* Intercept BIOS (Trap #13) calls */
          if (Bios())  return;
        }
        else if (nr == 0x2e)
        {
          /* Intercept XBIOS (Trap #14) calls */
          if (XBios())  return;
        }
      }

    MakeSR();

    /* Change to supervisor mode if necessary */
    if (!regs.s) {
	regs.usp = m68k_areg(regs, 7);
	if (currprefs.cpu_level >= 2)
	    m68k_areg(regs, 7) = regs.m ? regs.msp : regs.isp;
	else
	    m68k_areg(regs, 7) = regs.isp;
	regs.s = 1;
    }

    /* Build additional exception stack frame for 68010 and higher */
    /* (special case for MFP) */
    if (currprefs.cpu_level > 0) {
        if (ExceptionSource == M68000_EXC_SRC_INT_MFP
		    || ExceptionSource == M68000_EXC_SRC_INT_DSP) {
	    m68k_areg(regs, 7) -= 2;
	    put_word (m68k_areg(regs, 7), nr * 4);	/* MFP interrupt, 'nr' can be in a different range depending on $fffa17 */
        }
        else if (nr == 2 || nr == 3) {
	    int i;
	    /* @@@ this is probably wrong (?) */
	    for (i = 0 ; i < 12 ; i++) {
		m68k_areg(regs, 7) -= 2;
		put_word (m68k_areg(regs, 7), 0);
	    }
	    m68k_areg(regs, 7) -= 2;
	    put_word (m68k_areg(regs, 7), 0xa000 + nr * 4);
	} else if (nr ==5 || nr == 6 || nr == 7 || nr == 9) {
	    m68k_areg(regs, 7) -= 4;
	    put_long (m68k_areg(regs, 7), oldpc);
	    m68k_areg(regs, 7) -= 2;
	    put_word (m68k_areg(regs, 7), 0x2000 + nr * 4);
	} else if (regs.m && nr >= 24 && nr < 32) {
	    m68k_areg(regs, 7) -= 2;
	    put_word (m68k_areg(regs, 7), nr * 4);
	    m68k_areg(regs, 7) -= 4;
	    put_long (m68k_areg(regs, 7), currpc);
	    m68k_areg(regs, 7) -= 2;
	    put_word (m68k_areg(regs, 7), regs.sr);
	    regs.sr |= (1 << 13);
	    regs.msp = m68k_areg(regs, 7);
	    m68k_areg(regs, 7) = regs.isp;
	    m68k_areg(regs, 7) -= 2;
	    put_word (m68k_areg(regs, 7), 0x1000 + nr * 4);
	} else {
	    m68k_areg(regs, 7) -= 2;
	    put_word (m68k_areg(regs, 7), nr * 4);
	}
    }

    /* Push PC on stack: */
    m68k_areg(regs, 7) -= 4;
    put_long (m68k_areg(regs, 7), currpc);
    /* Push SR on stack: */
    m68k_areg(regs, 7) -= 2;
    put_word (m68k_areg(regs, 7), regs.sr);

    LOG_TRACE(TRACE_CPU_EXCEPTION, "cpu exception %d currpc %x buspc %x newpc %x fault_e3 %x op_e3 %hx addr_e3 %x\n",
	nr, currpc, BusErrorPC, get_long (regs.vbr + 4*nr), last_fault_for_exception_3, last_op_for_exception_3, last_addr_for_exception_3);

    /* 68000 bus/address errors: */
    if (currprefs.cpu_level==0 && (nr==2 || nr==3) && ExceptionSource == M68000_EXC_SRC_CPU) {
	uae_u16 specialstatus = last_instructionaccess_for_exception_3 ? 2 : 1;
	uae_u16 BusError_opcode;

	/* Special status word emulation isn't perfect yet... :-( */
	if (regs.sr & 0x2000)
	    specialstatus |= 0x4;
	m68k_areg(regs, 7) -= 8;
	if (nr == 3) {    /* Address error */
	    specialstatus |= ( last_op_for_exception_3 & (~0x1f) );	/* [NP] unused bits of specialstatus are those of the last opcode ! */
	    put_word (m68k_areg(regs, 7), specialstatus);
	    put_long (m68k_areg(regs, 7)+2, last_fault_for_exception_3);
	    put_word (m68k_areg(regs, 7)+6, last_op_for_exception_3);
	    put_long (m68k_areg(regs, 7)+10, last_addr_for_exception_3);
	    if (ExceptionDebugMask & EXCEPT_ADDRESS) {
	      fprintf(stderr,"Address Error at address $%x, PC=$%x\n",last_fault_for_exception_3,currpc);
	      DebugUI(REASON_CPU_EXCEPTION);
	    }
	}
	else {    /* Bus error */
	    /* Get the opcode that caused the bus error, to adapt the stack frame in some cases */
	    /* (we must call get_word() only on valid region, else this will cause a double bus error) */
	    if ( valid_address ( BusErrorPC , 2 ) )
	      BusError_opcode = get_word(BusErrorPC);
	    else
	      BusError_opcode = 0;

	    specialstatus |= ( BusError_opcode & (~0x1f) );		/* [NP] unused bits of special status are those of the last opcode ! */
	    if (bBusErrorReadWrite)
	      specialstatus |= 0x10;
	    put_word (m68k_areg(regs, 7), specialstatus);
	    put_long (m68k_areg(regs, 7)+2, BusErrorAddress);
	    put_word (m68k_areg(regs, 7)+6, BusError_opcode);		/* Opcode */

	    /* [NP] PC stored in the stack frame is not necessarily pointing to the next instruction ! */
	    /* FIXME : we should have a proper model for this, in the meantime we handle specific cases */
	    if ( BusError_opcode == 0x21f8 )						/* move.l $0.w,$24.w (Transbeauce 2 loader) */
	      put_long (m68k_areg(regs, 7)+10, currpc-2);				/* correct PC is 2 bytes less than usual value */

	    else if ( ( BusErrorPC == 0xccc ) && ( BusError_opcode == 0x48d6 ) )	/* 48d6 3f00 movem.l a0-a5,(a6) (Blood Money) */
	      put_long (m68k_areg(regs, 7)+10, currpc+2);				/* correct PC is 2 bytes more than usual value */

	    else if ( ( BusErrorPC == 0x1fece ) && ( BusError_opcode == 0x33d4 ) )	/* 1fece : 33d4 0001 fdca move.w (a4),$1fdca (Batman The Movie) */
	      put_long (m68k_areg(regs, 7)+10, currpc-4);				/* correct PC is 4 bytes less than usual value */

	    /* [NP] In case of a move with a bus error on the read part, uae cpu is writing to the dest part */
	    /* then process the bus error ; on a real CPU, the bus error occurs after the read and before the */
	    /* write, so the dest part doesn't change. For now, we restore the dest part on some specific cases */
	    /* FIXME : the bus error should be processed just after the read, not at the end of the instruction */
	    else if ( ( BusErrorPC == 0x62a ) && ( BusError_opcode == 0x3079 ) )	/* 3079 4ef9 0000 move.l $4ef90000,a0 (Dragon Flight) */
	      m68k_areg(regs, 0) = 8;							/* A0 should not be changed to "0" but keep its value "8" */

	    else if ( get_long(BusErrorPC) == 0x13f88e21 )				/* 13f8 8e21 move.b $ffff8e21.w,$xxxxx (Tymewarp) */
	      put_byte ( get_long(BusErrorPC+4) , 0x00 );				/* dest content should not be changed to "ff" but keep its value "00" */

	    fprintf(stderr,"Bus Error at address $%x, PC=$%lx %x %x\n", BusErrorAddress, (long)currpc, BusErrorPC , BusError_opcode);

	    /* Check for double bus errors: */
	    if (regs.spcflags & SPCFLAG_BUSERROR) {
	      fprintf(stderr, "Detected double bus error at address $%x, PC=$%lx => CPU halted!\n",
	              BusErrorAddress, (long)currpc);
	      unset_special(SPCFLAG_BUSERROR);
	      if (ExceptionDebugMask & EXCEPT_BUS)
	        DebugUI(REASON_CPU_EXCEPTION);
	      else
		DlgAlert_Notice("Detected double bus error => CPU halted!\nEmulation needs to be reset.\n");
	      regs.intmask = 7;
	      m68k_setstopped(true);
	      return;
	    }
	    if ((ExceptionDebugMask & EXCEPT_BUS) && BusErrorAddress!=0xff8a00) {
	      fprintf(stderr,"Bus Error at address $%x, PC=$%lx\n", BusErrorAddress, (long)currpc);
	      DebugUI(REASON_CPU_EXCEPTION);
	    }
	}
    }

    /* Set PC and flags */
    if ((ExceptionDebugMask & EXCEPT_NOHANDLER) && (regs.vbr + 4*nr) == 0) {
        fprintf(stderr,"Uninitialized exception handler #%i!\n", nr);
	DebugUI(REASON_CPU_EXCEPTION);
    }
    newpc = get_long (regs.vbr + 4*nr);
    if ( newpc & 1)				/* check new pc is even */
      {
        if ( nr==2 || nr==3 )			/* address error during bus/address error -> stop emulation */
            {
	      fprintf(stderr,"Address Error during exception 2/3, aborting new PC=$%x\n",newpc);
	      if (ExceptionDebugMask & (EXCEPT_BUS|EXCEPT_ADDRESS))
	        DebugUI(REASON_CPU_EXCEPTION);
	      else
		DlgAlert_Notice("Address Error during exception 2/3 => CPU halted!\nEmulation needs to be reset.\n");
            }
        else
            {
		fprintf(stderr,"Address Error during exception, new PC=$%x\n",newpc);
		Exception ( 3 , m68k_getpc() , M68000_EXC_SRC_CPU );
            }
        return;
      }
    /* handle debugger invocation for rest of exceptions */
    if (ExceptionDebugMask && nr > 3 && nr < 9)
      DebugUI_Exceptions(nr, currpc);

    m68k_setpc (get_long (regs.vbr + 4*nr));
    fill_prefetch_0 ();
    /* Handle trace flags depending on current state */
    exception_trace (nr);

    /* Handle exception cycles (special case for MFP) */
    if (ExceptionSource == M68000_EXC_SRC_INT_MFP)
    {
      M68000_AddCycles(44+12-CPU_IACK_CYCLES_MFP);	/* MFP interrupt, 'nr' can be in a different range depending on $fffa17 */
    }
    else if (nr >= 24 && nr <= 31)
    {
      if ( nr == 26 )					/* HBL */
        M68000_AddCycles(44+12-CPU_IACK_CYCLES_VIDEO);	/* Video Interrupt */
      else if ( nr == 28 ) 				/* VBL */
        M68000_AddCycles(44+12-CPU_IACK_CYCLES_VIDEO);	/* Video Interrupt */
      else
        M68000_AddCycles(44+4);				/* Other Interrupts */
    }
    else if(nr >= 32 && nr <= 47)
    {
      M68000_AddCycles(34-4);			/* Trap (total is 34, but cpuemu.c already adds 4) */
    }
    else switch(nr)
    {
      case 2: M68000_AddCycles(50); break;	/* Bus error */
      case 3: M68000_AddCycles(50); break;	/* Address error */
      case 4: M68000_AddCycles(34); break;	/* Illegal instruction */
      case 5: M68000_AddCycles(38); break;	/* Div by zero */
      case 6: M68000_AddCycles(40); break;	/* CHK */
      case 7: M68000_AddCycles(34); break;	/* TRAPV */
      case 8: M68000_AddCycles(34); break;	/* Privilege violation */
      case 9: M68000_AddCycles(34); break;	/* Trace */
      case 10: M68000_AddCycles(34); break;	/* Line-A - probably wrong */
      case 11: M68000_AddCycles(34); break;	/* Line-F - probably wrong */
      default:
        /* FIXME: Add right cycles value for MFP interrupts and copro exceptions ... */
        if(nr < 64)
          M68000_AddCycles(4);			/* Coprocessor and unassigned exceptions (???) */
        else
          M68000_AddCycles(44+12);		/* Must be a MFP or DSP interrupt */
        break;
    }

}


static void Interrupt(int nr , int Pending)
{
    assert(nr < 8 && nr >= 0);
    /*lastint_regs = regs;*/
    /*lastint_no = nr;*/

    /* On Hatari, only video ints are using SPCFLAG_INT (see m68000.c) */
    Exception(nr+24, 0, M68000_EXC_SRC_AUTOVEC);

    regs.intmask = nr;
    set_special (SPCFLAG_INT);

    /* Handle Atari ST's specific jitter for hbl/vbl */
    InterruptAddJitter ( nr , Pending );
}


uae_u32 caar, cacr;
static uae_u32 itt0, itt1, dtt0, dtt1, tc, mmusr, urp, srp;


static int movec_illg (int regno)
{
    int regno2 = regno & 0x7ff;
    if (currprefs.cpu_level == 1) { /* 68010 */
	if (regno2 < 2)
	    return 0;
	return 1;
    }
    if (currprefs.cpu_level == 2 || currprefs.cpu_level == 3) { /* 68020 */
	if (regno == 3) return 1; /* 68040 only */
	 /* 4 is >=68040, but 0x804 is in 68020 */
	 if (regno2 < 4 || regno == 0x804)
	    return 0;
	return 1;
    }
    if (currprefs.cpu_level >= 4) { /* 68040 */
	if (regno == 0x802) return 1; /* 68020 only */
	if (regno2 < 8) return 0;
	if (currprefs.cpu_level == 6 && regno2 == 8) /* 68060 only */
	    return 0;
	return 1;
    }
    return 1;
}

int m68k_move2c (int regno, uae_u32 *regp)
{
    if (movec_illg (regno)) {
	op_illg (0x4E7B);
	return 0;
    } else {
	switch (regno) {
	case 0: regs.sfc = *regp & 7; break;
	case 1: regs.dfc = *regp & 7; break;
	case 2:
	{
	    uae_u32 cacr_mask = 0;
	    if (currprefs.cpu_level == 2)	// 68020
		cacr_mask = 0x0000000f;
	    else if (currprefs.cpu_level == 3)	// Fake 68030
		cacr_mask = 0x00003f1f;
	    else if (currprefs.cpu_level == 4)	// 68040
		cacr_mask = 0x80008000;
	    cacr = *regp & cacr_mask;
	}
	case 3: tc = *regp & 0xc000; break;
	  /* Mask out fields that should be zero.  */
	case 4: itt0 = *regp & 0xffffe364; break;
	case 5: itt1 = *regp & 0xffffe364; break;
	case 6: dtt0 = *regp & 0xffffe364; break;
	case 7: dtt1 = *regp & 0xffffe364; break;

	case 0x800: regs.usp = *regp; break;
	case 0x801: regs.vbr = *regp; break;
	case 0x802: caar = *regp; break;
	case 0x803: regs.msp = *regp; if (regs.m == 1) m68k_areg(regs, 7) = regs.msp; break;
	case 0x804: regs.isp = *regp; if (regs.m == 0) m68k_areg(regs, 7) = regs.isp; break;
	case 0x805: mmusr = *regp; break;
	case 0x806: urp = *regp; break;
	case 0x807: srp = *regp; break;
	default:
	    op_illg (0x4E7B);
	    return 0;
	}
    }
    return 1;
}

int m68k_movec2 (int regno, uae_u32 *regp)
{
    if (movec_illg (regno)) {
	op_illg (0x4E7A);
	return 0;
    } else {
	switch (regno) {
	case 0: *regp = regs.sfc; break;
	case 1: *regp = regs.dfc; break;
	case 2: *regp = cacr; break;
	case 3: *regp = tc; break;
	case 4: *regp = itt0; break;
	case 5: *regp = itt1; break;
	case 6: *regp = dtt0; break;
	case 7: *regp = dtt1; break;
	case 0x800: *regp = regs.usp; break;
	case 0x801: *regp = regs.vbr; break;
	case 0x802: *regp = caar; break;
	case 0x803: *regp = regs.m == 1 ? m68k_areg(regs, 7) : regs.msp; break;
	case 0x804: *regp = regs.m == 0 ? m68k_areg(regs, 7) : regs.isp; break;
	case 0x805: *regp = mmusr; break;
	case 0x806: *regp = urp; break;
	case 0x807: *regp = srp; break;
	default:
	    op_illg (0x4E7A);
	    return 0;
	}
    }
    return 1;
}

STATIC_INLINE int
div_unsigned(uae_u32 src_hi, uae_u32 src_lo, uae_u32 ndiv, uae_u32 *quot, uae_u32 *rem)
{
	uae_u32 q = 0, cbit = 0;
	int i;

	if (ndiv <= src_hi) {
	    return 1;
	}
	for (i = 0 ; i < 32 ; i++) {
		cbit = src_hi & 0x80000000ul;
		src_hi <<= 1;
		if (src_lo & 0x80000000ul) src_hi++;
		src_lo <<= 1;
		q = q << 1;
		if (cbit || ndiv <= src_hi) {
			q |= 1;
			src_hi -= ndiv;
		}
	}
	*quot = q;
	*rem = src_hi;
	return 0;
}

void m68k_divl (uae_u32 opcode, uae_u32 src, uae_u16 extra, uaecptr oldpc)
{
#if defined(uae_s64)
    if (src == 0) {
	Exception (5, oldpc,M68000_EXC_SRC_CPU);
	return;
    }
    if (extra & 0x800) {
	/* signed variant */
	uae_s64 a = (uae_s64)(uae_s32)m68k_dreg(regs, (extra >> 12) & 7);
	uae_s64 quot, rem;

	if (extra & 0x400) {
	    a &= 0xffffffffu;
	    a |= (uae_s64)m68k_dreg(regs, extra & 7) << 32;
	}
	rem = a % (uae_s64)(uae_s32)src;
	quot = a / (uae_s64)(uae_s32)src;
	if ((quot & UVAL64(0xffffffff80000000)) != 0
	    && (quot & UVAL64(0xffffffff80000000)) != UVAL64(0xffffffff80000000))
	{
	    SET_VFLG (1);
	    SET_NFLG (1);
	    SET_CFLG (0);
	} else {
	    if (((uae_s32)rem < 0) != ((uae_s64)a < 0)) rem = -rem;
	    SET_VFLG (0);
	    SET_CFLG (0);
	    SET_ZFLG (((uae_s32)quot) == 0);
	    SET_NFLG (((uae_s32)quot) < 0);
	    m68k_dreg(regs, extra & 7) = rem;
	    m68k_dreg(regs, (extra >> 12) & 7) = quot;
	}
    } else {
	/* unsigned */
	uae_u64 a = (uae_u64)(uae_u32)m68k_dreg(regs, (extra >> 12) & 7);
	uae_u64 quot, rem;

	if (extra & 0x400) {
	    a &= 0xffffffffu;
	    a |= (uae_u64)m68k_dreg(regs, extra & 7) << 32;
	}
	rem = a % (uae_u64)src;
	quot = a / (uae_u64)src;
	if (quot > 0xffffffffu) {
	    SET_VFLG (1);
	    SET_NFLG (1);
	    SET_CFLG (0);
	} else {
	    SET_VFLG (0);
	    SET_CFLG (0);
	    SET_ZFLG (((uae_s32)quot) == 0);
	    SET_NFLG (((uae_s32)quot) < 0);
	    m68k_dreg(regs, extra & 7) = rem;
	    m68k_dreg(regs, (extra >> 12) & 7) = quot;
	}
    }
#else
    if (src == 0) {
	Exception (5, oldpc,M68000_EXC_SRC_CPU);
	return;
    }
    if (extra & 0x800) {
	/* signed variant */
	uae_s32 lo = (uae_s32)m68k_dreg(regs, (extra >> 12) & 7);
	uae_s32 hi = lo < 0 ? -1 : 0;
	uae_s32 save_high;
	uae_u32 quot, rem;
	uae_u32 sign;

	if (extra & 0x400) {
	    hi = (uae_s32)m68k_dreg(regs, extra & 7);
	}
	save_high = hi;
	sign = (hi ^ src);
	if (hi < 0) {
	    hi = ~hi;
	    lo = -lo;
	    if (lo == 0) hi++;
	}
	if ((uae_s32)src < 0) src = -src;
	if (div_unsigned(hi, lo, src, &quot, &rem) ||
	    (sign & 0x80000000) ? quot > 0x80000000 : quot > 0x7fffffff) {
	    SET_VFLG (1);
	    SET_NFLG (1);
	    SET_CFLG (0);
	} else {
	    if (sign & 0x80000000) quot = -quot;
	    if (((uae_s32)rem < 0) != (save_high < 0)) rem = -rem;
	    SET_VFLG (0);
	    SET_CFLG (0);
	    SET_ZFLG (((uae_s32)quot) == 0);
	    SET_NFLG (((uae_s32)quot) < 0);
	    m68k_dreg(regs, extra & 7) = rem;
	    m68k_dreg(regs, (extra >> 12) & 7) = quot;
	}
    } else {
	/* unsigned */
	uae_u32 lo = (uae_u32)m68k_dreg(regs, (extra >> 12) & 7);
	uae_u32 hi = 0;
	uae_u32 quot, rem;

	if (extra & 0x400) {
	    hi = (uae_u32)m68k_dreg(regs, extra & 7);
	}
	if (div_unsigned(hi, lo, src, &quot, &rem)) {
	    SET_VFLG (1);
	    SET_NFLG (1);
	    SET_CFLG (0);
	} else {
	    SET_VFLG (0);
	    SET_CFLG (0);
	    SET_ZFLG (((uae_s32)quot) == 0);
	    SET_NFLG (((uae_s32)quot) < 0);
	    m68k_dreg(regs, extra & 7) = rem;
	    m68k_dreg(regs, (extra >> 12) & 7) = quot;
	}
    }
#endif
}

STATIC_INLINE void
mul_unsigned(uae_u32 src1, uae_u32 src2, uae_u32 *dst_hi, uae_u32 *dst_lo)
{
	uae_u32 r0 = (src1 & 0xffff) * (src2 & 0xffff);
	uae_u32 r1 = ((src1 >> 16) & 0xffff) * (src2 & 0xffff);
	uae_u32 r2 = (src1 & 0xffff) * ((src2 >> 16) & 0xffff);
	uae_u32 r3 = ((src1 >> 16) & 0xffff) * ((src2 >> 16) & 0xffff);
	uae_u32 lo;

	lo = r0 + ((r1 << 16) & 0xffff0000ul);
	if (lo < r0) r3++;
	r0 = lo;
	lo = r0 + ((r2 << 16) & 0xffff0000ul);
	if (lo < r0) r3++;
	r3 += ((r1 >> 16) & 0xffff) + ((r2 >> 16) & 0xffff);
	*dst_lo = lo;
	*dst_hi = r3;
}

void m68k_mull (uae_u32 opcode, uae_u32 src, uae_u16 extra)
{
#if defined(uae_s64)
    if (extra & 0x800) {
	/* signed variant */
	uae_s64 a = (uae_s64)(uae_s32)m68k_dreg(regs, (extra >> 12) & 7);

	a *= (uae_s64)(uae_s32)src;
	SET_VFLG (0);
	SET_CFLG (0);
	SET_ZFLG (a == 0);
	SET_NFLG (a < 0);
	if (extra & 0x400)
	    m68k_dreg(regs, extra & 7) = a >> 32;
	else if ((a & UVAL64(0xffffffff80000000)) != 0
		 && (a & UVAL64(0xffffffff80000000)) != UVAL64(0xffffffff80000000))
	{
	    SET_VFLG (1);
	}
	m68k_dreg(regs, (extra >> 12) & 7) = (uae_u32)a;
    } else {
	/* unsigned */
	uae_u64 a = (uae_u64)(uae_u32)m68k_dreg(regs, (extra >> 12) & 7);

	a *= (uae_u64)src;
	SET_VFLG (0);
	SET_CFLG (0);
	SET_ZFLG (a == 0);
	SET_NFLG (((uae_s64)a) < 0);
	if (extra & 0x400)
	    m68k_dreg(regs, extra & 7) = a >> 32;
	else if ((a & UVAL64(0xffffffff00000000)) != 0) {
	    SET_VFLG (1);
	}
	m68k_dreg(regs, (extra >> 12) & 7) = (uae_u32)a;
    }
#else
    if (extra & 0x800) {
	/* signed variant */
	uae_s32 src1,src2;
	uae_u32 dst_lo,dst_hi;
	uae_u32 sign;

	src1 = (uae_s32)src;
	src2 = (uae_s32)m68k_dreg(regs, (extra >> 12) & 7);
	sign = (src1 ^ src2);
	if (src1 < 0) src1 = -src1;
	if (src2 < 0) src2 = -src2;
	mul_unsigned((uae_u32)src1,(uae_u32)src2,&dst_hi,&dst_lo);
	if (sign & 0x80000000) {
		dst_hi = ~dst_hi;
		dst_lo = -dst_lo;
		if (dst_lo == 0) dst_hi++;
	}
	SET_VFLG (0);
	SET_CFLG (0);
	SET_ZFLG (dst_hi == 0 && dst_lo == 0);
	SET_NFLG (((uae_s32)dst_hi) < 0);
	if (extra & 0x400)
	    m68k_dreg(regs, extra & 7) = dst_hi;
	else if ((dst_hi != 0 || (dst_lo & 0x80000000) != 0)
		 && ((dst_hi & 0xffffffff) != 0xffffffff
		     || (dst_lo & 0x80000000) != 0x80000000))
	{
	    SET_VFLG (1);
	}
	m68k_dreg(regs, (extra >> 12) & 7) = dst_lo;
    } else {
	/* unsigned */
	uae_u32 dst_lo,dst_hi;

	mul_unsigned(src,(uae_u32)m68k_dreg(regs, (extra >> 12) & 7),&dst_hi,&dst_lo);

	SET_VFLG (0);
	SET_CFLG (0);
	SET_ZFLG (dst_hi == 0 && dst_lo == 0);
	SET_NFLG (((uae_s32)dst_hi) < 0);
	if (extra & 0x400)
	    m68k_dreg(regs, extra & 7) = dst_hi;
	else if (dst_hi != 0) {
	    SET_VFLG (1);
	}
	m68k_dreg(regs, (extra >> 12) & 7) = dst_lo;
    }
#endif
}


void m68k_reset (void)
{
    regs.s = 1;
    regs.m = 0;
    regs.stopped = 0;
    regs.t1 = 0;
    regs.t0 = 0;
    SET_ZFLG (0);
    SET_XFLG (0);
    SET_CFLG (0);
    SET_VFLG (0);
    SET_NFLG (0);
    regs.spcflags &= ( SPCFLAG_MODE_CHANGE | SPCFLAG_DEBUGGER );	/* Clear specialflags except mode-change and debugger */
    regs.intmask = 7;
    regs.vbr = regs.sfc = regs.dfc = 0;
    regs.fpcr = regs.fpsr = regs.fpiar = 0;

    m68k_areg(regs, 7) = get_long(0);
    m68k_setpc(get_long(4));
    refill_prefetch (m68k_getpc(), 0);
}


unsigned long REGPARAM2 op_illg (uae_u32 opcode)
{
#if 0
    uaecptr pc = m68k_getpc ();
#endif
    if ((opcode & 0xF000) == 0xF000) {
	Exception(0xB,0,M68000_EXC_SRC_CPU);
	return 4;
    }
    if ((opcode & 0xF000) == 0xA000) {
	Exception(0xA,0,M68000_EXC_SRC_CPU);
	return 4;
    }
#if 0
    write_log ("Illegal instruction: %04x at %08lx\n", opcode, (long)pc);
#endif
    Exception (4,0,M68000_EXC_SRC_CPU);
    return 4;
}


void mmu_op(uae_u32 opcode, uae_u16 extra)
{
    if ((opcode & 0xFE0) == 0x0500) {
	/* PFLUSH */
	mmusr = 0;
	write_log ("PFLUSH\n");
    } else if ((opcode & 0x0FD8) == 0x548) {
	/* PTEST */
	write_log ("PTEST\n");
    } else
	op_illg (opcode);
}


static uaecptr last_trace_ad = 0;

static void do_trace (void)
{
    if (regs.t0 && currprefs.cpu_level >= 2) {
	uae_u16 opcode;
	/* should also include TRAP, CHK, SR modification FPcc */
	/* probably never used so why bother */
	/* We can afford this to be inefficient... */
	m68k_setpc (m68k_getpc ());
	fill_prefetch_0 ();
	opcode = get_word (regs.pc);
	if (opcode == 0x4e73 		/* RTE */
	    || opcode == 0x4e74 		/* RTD */
	    || opcode == 0x4e75 		/* RTS */
	    || opcode == 0x4e77 		/* RTR */
	    || opcode == 0x4e76 		/* TRAPV */
	    || (opcode & 0xffc0) == 0x4e80 	/* JSR */
	    || (opcode & 0xffc0) == 0x4ec0 	/* JMP */
	    || (opcode & 0xff00) == 0x6100  /* BSR */
	    || ((opcode & 0xf000) == 0x6000	/* Bcc */
		&& cctrue((opcode >> 8) & 0xf))
	    || ((opcode & 0xf0f0) == 0x5050 /* DBcc */
		&& !cctrue((opcode >> 8) & 0xf)
		&& (uae_s16)m68k_dreg(regs, opcode & 7) != 0))
	{
	    last_trace_ad = m68k_getpc ();
	    unset_special (SPCFLAG_TRACE);
	    set_special (SPCFLAG_DOTRACE);
	}
    } else if (regs.t1) {
	last_trace_ad = m68k_getpc ();
	unset_special (SPCFLAG_TRACE);
	set_special (SPCFLAG_DOTRACE);
    }
}


/*
 * Handle special flags
 */

static bool do_specialties_interrupt (int Pending)
{
#if ENABLE_DSP_EMU
    /* Check for DSP int first (if enabled) (level 6) */
    if (regs.spcflags & SPCFLAG_DSP) {
       if (DSP_ProcessIRQ() == true)
         return true;
    }
#endif

    /* Check for MFP ints (level 6) */
    if (regs.spcflags & SPCFLAG_MFP) {
       if (MFP_ProcessIRQ() == true)
         return true;					/* MFP exception was generated, no higher interrupt can happen */
    }

    /* No MFP int, check for VBL/HBL ints (levels 4/2) */
    if (regs.spcflags & (SPCFLAG_INT | SPCFLAG_DOINT)) {
	int intr = intlev ();
	/* SPCFLAG_DOINT will be enabled again in MakeFromSR to handle pending interrupts! */
//	unset_special (SPCFLAG_DOINT);
	unset_special (SPCFLAG_INT | SPCFLAG_DOINT);
	if (intr != -1 && intr > regs.intmask) {
	    Interrupt (intr , Pending);			/* process the interrupt and add pending jitter if necessary */
	    return true;
	}
    }

    return false;					/* no interrupt was found */
}


static int do_specialties (void)
{
    if(regs.spcflags & SPCFLAG_BUSERROR) {
	/* We can not execute bus errors directly in the memory handler
	 * functions since the PC should point to the address of the next
	 * instruction, so we're executing the bus errors here: */
	unset_special(SPCFLAG_BUSERROR);
	Exception(2,0,M68000_EXC_SRC_CPU);
    }

    if(regs.spcflags & SPCFLAG_EXTRA_CYCLES) {
	/* Add some extra cycles to simulate a wait state */
	unset_special(SPCFLAG_EXTRA_CYCLES);
	M68000_AddCycles(nWaitStateCycles);
	nWaitStateCycles = 0;
    }

    if (regs.spcflags & SPCFLAG_DOTRACE) {
	Exception (9,last_trace_ad,M68000_EXC_SRC_CPU);
    }


    /* Handle the STOP instruction */
    if ( regs.spcflags & SPCFLAG_STOP ) {
//fprintf ( stderr , "test stop %d\n" , nCyclesMainCounter );
        /* We first test if there's a pending interrupt that would */
        /* allow to immediately leave the STOP state */
        if ( do_specialties_interrupt(true) ) {		/* test if there's an interrupt and add pending jitter */
            regs.stopped = 0;
            unset_special (SPCFLAG_STOP);
//fprintf ( stderr , "exit stop %d\n" , nCyclesMainCounter );
        }

	/* No pending int, we have to wait for the next matching int */
	while (regs.spcflags & SPCFLAG_STOP) {

	    /* Take care of quit event if needed */
	    if (regs.spcflags & SPCFLAG_BRK)
		return 1;

	    M68000_AddCycles(4);

	    /* It is possible one or more ints happen at the same time */
	    /* We must process them during the same cpu cycle then choose the highest priority one */
	    while ( ( PendingInterruptCount <= 0 ) && ( PendingInterruptFunction ) )
		CALL_VAR(PendingInterruptFunction);
	    if ( MFP_UpdateNeeded == true )
	        MFP_UpdateIRQ ( 0 );

	    /* Check is there's an interrupt to process (could be a delayed MFP interrupt) */
	    if ( do_specialties_interrupt(false) ) {	/* test if there's an interrupt and add non pending jitter */
		regs.stopped = 0;
		unset_special (SPCFLAG_STOP);
	    }
	}
    }


    if (regs.spcflags & SPCFLAG_TRACE)
	do_trace ();

//    if (regs.spcflags & SPCFLAG_DOINT) {
    /* [NP] pending int should be processed now, not after the current instr */
    /* so we check for (SPCFLAG_INT | SPCFLAG_DOINT), not just for SPCFLAG_DOINT */

    if ( do_specialties_interrupt(false) ) {	/* test if there's an interrupt and add non pending jitter */
        regs.stopped = 0;			/* [NP] useless ? */
    }
    if (regs.spcflags & SPCFLAG_INT) {
	unset_special (SPCFLAG_INT);
	set_special (SPCFLAG_DOINT);
    }

    if (regs.spcflags & SPCFLAG_DEBUGGER)
	DebugCpu_Check();

    if (regs.spcflags & (SPCFLAG_BRK | SPCFLAG_MODE_CHANGE)) {
	unset_special(SPCFLAG_MODE_CHANGE);
	return 1;
    }

    return 0;
}


/* It's really sad to have two almost identical functions for this, but we
   do it all for performance... :( */
static void m68k_run_1 (void)
{
#ifdef DEBUG_PREFETCH
    uae_u8 saved_bytes[20];
    uae_u8 *oldpcp;
#endif

    for (;;) {
	int cycles;
//fprintf (stderr, "ir in  %x %x\n",do_get_mem_long(&regs.prefetch) , regs.prefetch_pc);
	uae_u32 opcode = get_iword_prefetch (0);

	if (regs.spcflags & SPCFLAG_BUSERROR)
	{
	    unset_special(SPCFLAG_BUSERROR);
	    Exception(2,0,M68000_EXC_SRC_CPU);

	    /* Get opcode for bus error handler and check other special bits */
	    opcode = get_iword_prefetch (0);
	    if (regs.spcflags) {
		if (do_specialties ())
		    return;
	    }
	}

#ifdef DEBUG_PREFETCH
//	if (get_ilong (0) != do_get_mem_long (&regs.prefetch)) {
//	    fprintf (stderr, "Prefetch differs from memory.\n");
//	    debugging = 1;
//	    return;
//	}
	oldpcp = regs.pc_p;
	memcpy (saved_bytes, regs.pc_p, 20);
#endif

	/*m68k_dumpstate(stderr, NULL);*/
	if (LOG_TRACE_LEVEL(TRACE_CPU_DISASM))
	{
	    int FrameCycles, HblCounterVideo, LineCycles;

	    Video_GetPosition ( &FrameCycles , &HblCounterVideo , &LineCycles );

	    LOG_TRACE_PRINT ( "cpu video_cyc=%6d %3d@%3d : " , FrameCycles, LineCycles, HblCounterVideo );
	    Disasm(stderr, m68k_getpc (), NULL, 1);
	}

	/* assert (!regs.stopped && !(regs.spcflags & SPCFLAG_STOP)); */
/*	regs_backup[backup_pointer = (backup_pointer + 1) % 16] = regs;*/
#if COUNT_INSTRS == 2
	if (table68k[opcode].handler != -1)
	    instrcount[table68k[opcode].handler]++;
#elif COUNT_INSTRS == 1
	instrcount[opcode]++;
#endif

	/* In case of a Bus Error, we need the PC of the instruction that caused */
	/* the error to build the exception stack frame */
	BusErrorPC = m68k_getpc();

	if (bDspEnabled)
	    Cycles_SetCounter(CYCLES_COUNTER_CPU, 0);	/* to measure the total number of cycles spent in the cpu */

	/* Uncomment following lines to call capslib's debugger after each instruction */
	//if ( CAPSGetDebugRequest() )
	//  DebugUI(REASON_CPU_BREAKPOINT);

	cycles = (*cpufunctbl[opcode])(opcode);
//fprintf (stderr, "ir out %x %x\n",do_get_mem_long(&regs.prefetch) , regs.prefetch_pc);

#ifdef DEBUG_PREFETCH
	if (memcmp (saved_bytes, oldpcp, 20) != 0) {
	    fprintf (stderr, "Self-modifying code detected %x.\n" , m68k_getpc() );
//	    set_special (SPCFLAG_BRK);
//	    debugging = 1;
	}
#endif

	M68000_AddCyclesWithPairing(cycles);
	if (regs.spcflags & SPCFLAG_EXTRA_CYCLES) {
	  /* Add some extra cycles to simulate a wait state */
	  unset_special(SPCFLAG_EXTRA_CYCLES);
	  M68000_AddCycles(nWaitStateCycles);
	  nWaitStateCycles = 0;
	}

	/* We can have several interrupts at the same time before the next CPU instruction */
	/* We must check for pending interrupt and call do_specialties_interrupt() only */
	/* if the cpu is not in the STOP state. Else, the int could be acknowledged now */
	/* and prevent exiting the STOP state when calling do_specialties() after. */
	/* For performance, we first test PendingInterruptCount, then regs.spcflags */
	if ( PendingInterruptCount <= 0 )
	{
	    while ( ( PendingInterruptCount <= 0 ) && ( PendingInterruptFunction ) && ( ( regs.spcflags & SPCFLAG_STOP ) == 0 ) )
		CALL_VAR ( PendingInterruptFunction );		/* call the interrupt's handler */
	    if ( MFP_UpdateNeeded == true )
		MFP_UpdateIRQ ( 0 );				/* update MFP's state if some internal timers related to MFP expired */
	}

	if (regs.spcflags) {
	    if (do_specialties ())
		return;
	}

	/* Run DSP 56k code if necessary */
	if (bDspEnabled) {
	    DSP_Run( Cycles_GetCounter(CYCLES_COUNTER_CPU) * 2);
	}
    }
}


/* Same thing, but don't use prefetch to get opcode.  */
static void m68k_run_2 (void)
{
    for (;;) {
	int cycles;
	uae_u32 opcode = get_iword (0);

	/*m68k_dumpstate(stderr, NULL);*/
	if (LOG_TRACE_LEVEL(TRACE_CPU_DISASM))
	{
	    int FrameCycles, HblCounterVideo, LineCycles;

	    Video_GetPosition ( &FrameCycles , &HblCounterVideo , &LineCycles );

	    LOG_TRACE_PRINT ( "cpu video_cyc=%6d %3d@%3d : " , FrameCycles, LineCycles, HblCounterVideo );
	    Disasm(stderr, m68k_getpc (), NULL, 1);
	}

	/* assert (!regs.stopped && !(regs.spcflags & SPCFLAG_STOP)); */
/*	regs_backup[backup_pointer = (backup_pointer + 1) % 16] = regs;*/
#if COUNT_INSTRS == 2
	if (table68k[opcode].handler != -1)
	    instrcount[table68k[opcode].handler]++;
#elif COUNT_INSTRS == 1
	instrcount[opcode]++;
#endif

	/* In case of a Bus Error, we need the PC of the instruction that caused */
	/* the error to build the exception stack frame */
	BusErrorPC = m68k_getpc();

	cycles = (*cpufunctbl[opcode])(opcode);

	if (bDspEnabled)
	    Cycles_SetCounter(CYCLES_COUNTER_CPU, 0);	/* to measure the total number of cycles spent in the cpu */

	M68000_AddCycles(cycles);
	if (regs.spcflags & SPCFLAG_EXTRA_CYCLES) {
	  /* Add some extra cycles to simulate a wait state */
	  unset_special(SPCFLAG_EXTRA_CYCLES);
	  M68000_AddCycles(nWaitStateCycles);
	  nWaitStateCycles = 0;
	}

        if ( PendingInterruptCount <= 0 )
	{
	    while ( ( PendingInterruptCount <= 0 ) && ( PendingInterruptFunction ) )
		CALL_VAR(PendingInterruptFunction);
	    if ( MFP_UpdateNeeded == true )
		MFP_UpdateIRQ ( 0 );
	}

	if (regs.spcflags) {
	    if (do_specialties ())
		return;
	}

	/* Run DSP 56k code if necessary */
	if (bDspEnabled) {
	    DSP_Run( Cycles_GetCounter(CYCLES_COUNTER_CPU) );
	}
    }
}


void m68k_go (int may_quit)
{
    static int in_m68k_go = 0;

    if (in_m68k_go || !may_quit) {
	write_log ("Bug! m68k_go is not reentrant.\n");
	abort ();
    }

    in_m68k_go++;
    while (!(regs.spcflags & SPCFLAG_BRK)) {
        if(currprefs.cpu_compatible)
          m68k_run_1();
         else
          m68k_run_2();
    }
    unset_special(SPCFLAG_BRK);
    in_m68k_go--;
}


/*
static void m68k_verify (uaecptr addr, uaecptr *nextpc)
{
    uae_u32 opcode, val;
    struct instr *dp;

    opcode = get_iword_1(0);
    last_op_for_exception_3 = opcode;
    m68kpc_offset = 2;

    if (cpufunctbl[opcode] == op_illg_1) {
	opcode = 0x4AFC;
    }
    dp = table68k + opcode;

    if (dp->suse) {
	if (!verify_ea (dp->sreg, dp->smode, dp->size, &val)) {
	    Exception (3, 0,M68000_EXC_SRC_CPU);
	    return;
	}
    }
    if (dp->duse) {
	if (!verify_ea (dp->dreg, dp->dmode, dp->size, &val)) {
	    Exception (3, 0,M68000_EXC_SRC_CPU);
	    return;
	}
    }
}
*/


void m68k_disasm (FILE *f, uaecptr addr, uaecptr *nextpc, int cnt)
{
    static const char * const ccnames[] =
        { "T ","F ","HI","LS","CC","CS","NE","EQ",
          "VC","VS","PL","MI","GE","LT","GT","LE" };

    uaecptr newpc = 0;
    m68kpc_offset = addr - m68k_getpc ();
    while (cnt-- > 0) {
	char instrname[20],*ccpt;
	int opwords;
	uae_u32 opcode;
	const struct mnemolookup *lookup;
	struct instr *dp;
	fprintf (f, "%08lx: ", m68k_getpc () + m68kpc_offset);
	for (opwords = 0; opwords < 5; opwords++){
	    if ( valid_address ( m68k_getpc () + m68kpc_offset + opwords*2 , 2 ) )
	        fprintf (f, "%04x ", get_iword_1 (m68kpc_offset + opwords*2));
	    else
	        fprintf (f, "**** " );
	}
	if ( ! valid_address ( m68k_getpc () + m68kpc_offset , 2 ) ) {
	    fprintf (f , "BUS ERROR\n" );			/* If region is not valid (bus error region) */
	    m68kpc_offset += 2;
	    continue;
	}

	opcode = get_iword_1 (m68kpc_offset);
	m68kpc_offset += 2;
	if (cpufunctbl[opcode] == op_illg_1) {
	    opcode = 0x4AFC;
	}
	dp = table68k + opcode;
	for (lookup = lookuptab;lookup->mnemo != dp->mnemo; lookup++)
	    ;

	strcpy (instrname, lookup->name);
	ccpt = strstr (instrname, "cc");
	if (ccpt != 0) {
	    strncpy (ccpt, ccnames[dp->cc], 2);
	}
	fprintf (f, "%s", instrname);
	switch (dp->size){
	 case sz_byte: fprintf (f, ".B "); break;
	 case sz_word: fprintf (f, ".W "); break;
	 case sz_long: fprintf (f, ".L "); break;
	 default: fprintf (f, "   "); break;
	}

	if (dp->suse) {
	    newpc = m68k_getpc () + m68kpc_offset;
	    newpc += ShowEA (f, dp->sreg, dp->smode, dp->size, 0);
	}
	if (dp->suse && dp->duse)
	    fprintf (f, ",");
	if (dp->duse) {
	    newpc = m68k_getpc () + m68kpc_offset;
	    newpc += ShowEA (f, dp->dreg, dp->dmode, dp->size, 0);
	}
	if (ccpt != 0) {
	    if (cctrue(dp->cc))
		fprintf (f, " == %08lx (TRUE)", (long)newpc);
	    else
		fprintf (f, " == %08lx (FALSE)", (long)newpc);
	} else if ((opcode & 0xff00) == 0x6100) /* BSR */
	    fprintf (f, " == %08lx", (long)newpc);
	fprintf (f, "\n");
    }
    if (nextpc)
	*nextpc = m68k_getpc () + m68kpc_offset;
}

void m68k_dumpstate (FILE *f, uaecptr *nextpc)
{
    int i;
    for (i = 0; i < 8; i++){
	fprintf (f, "D%d: %08lx ", i, (long)m68k_dreg(regs, i));
	if ((i & 3) == 3) fprintf (f, "\n");
    }
    for (i = 0; i < 8; i++){
	fprintf (f, "A%d: %08lx ", i, (long)m68k_areg(regs, i));
	if ((i & 3) == 3) fprintf (f, "\n");
    }
    if (regs.s == 0) regs.usp = m68k_areg(regs, 7);
    if (regs.s && regs.m) regs.msp = m68k_areg(regs, 7);
    if (regs.s && regs.m == 0) regs.isp = m68k_areg(regs, 7);
    fprintf (f, "USP=%08lx ISP=%08lx MSP=%08lx VBR=%08lx\n",
	     (long)regs.usp,(long)regs.isp,(long)regs.msp,(long)regs.vbr);
    fprintf (f, "T=%d%d S=%d M=%d X=%d N=%d Z=%d V=%d C=%d IMASK=%d\n",
	     regs.t1, regs.t0, regs.s, regs.m,
	     GET_XFLG, GET_NFLG, GET_ZFLG, GET_VFLG, GET_CFLG, regs.intmask);
    for (i = 0; i < 8; i++){
	fprintf (f, "FP%d: %g ", i, regs.fp[i]);
	if ((i & 3) == 3) fprintf (f, "\n");
    }
    fprintf (f, "N=%d Z=%d I=%d NAN=%d\n",
	     (regs.fpsr & 0x8000000) != 0,
	     (regs.fpsr & 0x4000000) != 0,
	     (regs.fpsr & 0x2000000) != 0,
	     (regs.fpsr & 0x1000000) != 0);
    if (currprefs.cpu_compatible)
	fprintf (f, "prefetch %08lx\n", (unsigned long)do_get_mem_long(&regs.prefetch));

    m68k_disasm (f, m68k_getpc (), nextpc, 1);
    if (nextpc)
	fprintf (f, "next PC: %08lx\n", (long)*nextpc);
}


/*

 The routines below take dividend and divisor as parameters.
 They return 0 if division by zero, or exact number of cycles otherwise.

 The number of cycles returned assumes a register operand.
 Effective address time must be added if memory operand.

 For 68000 only (not 68010, 68012, 68020, etc).
 Probably valid for 68008 after adding the extra prefetch cycle.


 Best and worst cases are for register operand:
 (Note the difference with the documented range.)


 DIVU:

 Overflow (always): 10 cycles.
 Worst case: 136 cycles.
 Best case: 76 cycles.


 DIVS:

 Absolute overflow: 16-18 cycles.
 Signed overflow is not detected prematurely.

 Worst case: 156 cycles.
 Best case without signed overflow: 122 cycles.
 Best case with signed overflow: 120 cycles


 */


//
// DIVU
// Unsigned division
//

STATIC_INLINE int getDivu68kCycles_2 (uae_u32 dividend, uae_u16 divisor)
{
    int mcycles;
    uae_u32 hdivisor;
    int i;

    if (divisor == 0)
	return 0;

    // Overflow
    if ((dividend >> 16) >= divisor)
	return (mcycles = 5) * 2;

    mcycles = 38;
    hdivisor = divisor << 16;

    for (i = 0; i < 15; i++) {
	uae_u32 temp;
	temp = dividend;

	dividend <<= 1;

	// If carry from shift
	if ((uae_s32)temp < 0)
	    dividend -= hdivisor;
	else {
	    mcycles += 2;
	    if (dividend >= hdivisor) {
		dividend -= hdivisor;
		mcycles--;
	    }
	}
    }
    return mcycles * 2;
}
int getDivu68kCycles (uae_u32 dividend, uae_u16 divisor)
{
    int v = getDivu68kCycles_2 (dividend, divisor) - 4;
//    write_log ("U%d ", v);
    return v;
}

//
// DIVS
// Signed division
//

STATIC_INLINE int getDivs68kCycles_2 (uae_s32 dividend, uae_s16 divisor)
{
    int mcycles;
    uae_u32 aquot;
    int i;

    if (divisor == 0)
	return 0;

    mcycles = 6;

    if (dividend < 0)
	mcycles++;

    // Check for absolute overflow
    if (((uae_u32)abs (dividend) >> 16) >= (uae_u16)abs (divisor))
	return (mcycles + 2) * 2;

    // Absolute quotient
    aquot = (uae_u32) abs (dividend) / (uae_u16)abs (divisor);

    mcycles += 55;

    if (divisor >= 0) {
	if (dividend >= 0)
	    mcycles--;
	else
	    mcycles++;
    }

    // Count 15 msbits in absolute of quotient

    for (i = 0; i < 15; i++) {
	if ((uae_s16)aquot >= 0)
	    mcycles++;
	aquot <<= 1;
    }

    return mcycles * 2;
}
int getDivs68kCycles (uae_s32 dividend, uae_s16 divisor)
{
    int v = getDivs68kCycles_2 (dividend, divisor) - 4;
//    write_log ("S%d ", v);
    return v;
}