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/*	$OpenBSD: db_disasm.c,v 1.10 2002/03/14 01:26:38 millert Exp $	*/
/*
 * Mach Operating System
 * Copyright (c) 1993-1991 Carnegie Mellon University
 * Copyright (c) 1991 OMRON Corporation
 * All Rights Reserved.
 *
 * Permission to use, copy, modify and distribute this software and its
 * documentation is hereby granted, provided that both the copyright
 * notice and this permission notice appear in all copies of the
 * software, derivative works or modified versions, and any portions
 * thereof, and that both notices appear in supporting documentation.
 *
 * CARNEGIE MELLON AND OMRON ALLOW FREE USE OF THIS SOFTWARE IN ITS "AS IS"
 * CONDITION.  CARNEGIE MELLON AND OMRON DISCLAIM ANY LIABILITY OF ANY KIND
 * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
 *
 * Carnegie Mellon requests users of this software to return to
 *
 *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
 *  School of Computer Science
 *  Carnegie Mellon University
 *  Pittsburgh PA 15213-3890
 *
 * any improvements or extensions that they make and grant Carnegie the
 * rights to redistribute these changes.
 */

/*
 * m88k disassembler for use in ddb
 */

#include <sys/param.h>		/* cputyp and friends */
#include <sys/types.h>

#include <machine/db_machdep.h>

#include <ddb/db_sym.h>		/* DB_STGY_PROC, db_printsym() */
#include <ddb/db_access.h>	/* db_get_value() */
#include <ddb/db_output.h>	/* db_printf() */
#include <ddb/db_interface.h>

static char *instwidth[4] = {
	".d", "  ", ".h", ".b"
};

static char *condname[6] = {
	"gt0 ", "eq0 ", "ge0 ", "lt0 ", "ne0 ", "le0 "
};  

static char *m88100_ctrlreg[64] = {
	"cr0(PID)   ",
	"cr1(PSR)   ",
	"cr2(EPSR)  ",
	"cr3(SSBR)  ",
	"cr4(SXIP)  ",
	"cr5(SNIP)  ",
	"cr6(SFIP)  ",
	"cr7(VBR)   ",
	"cr8(DMT0)  ",
	"cr9(DMD0)  ",
	"cr10(DMA0) ",
	"cr11(DMT1) ",
	"cr12(DMD1) ",
	"cr13(DMA1) ",
	"cr14(DMT2) ",
	"cr15(DMD2) ",
	"cr16(DMA2) ",
	"cr17(SR0)  ",
	"cr18(SR1)  ",
	"cr19(SR2)  ",
	"cr20(SR3)  ",
	"fcr0(FPECR)",
	"fcr1(FPHS1)",
	"fcr2(FPLS1)",
	"fcr3(FPHS2)",
	"fcr4(FPLS2)",
	"fcr5(FPPT) ",
	"fcr6(FPRH) ",
	"fcr7(FPRL) ",
	"fcr8(FPIT) ",
	0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
	"fcr62(FPSR)",
	"fcr63(FPCR)"
};

static char *m88110_ctrlreg[64] = {
	"cr0(PID)   ",
	"cr1(PSR)   ",
	"cr2(EPSR)  ",
	0,
	"cr4(EXIP)  ",
	"cr5(ENIP)  ",
	0,
	"cr7(VBR)   ",
	0,
	0,
	0,
	0,
	0,
	0,
	"cr14(RES1) ",
	"cr15(RES2) ",
	"cr16(SR0)  ",
	"cr17(SR1)  ",
	"cr18(SR2)  ",
	"cr19(SR3)  ",
	"cr20(SR4)  ",
	"fcr0(FPECR)",
	0,
	0,
	0,
	"cr25(ICMD) ",
	"cr26(ICTL) ",
	"cr27(ISAR) ",
	"cr28(ISAP) ",
	"cr29(IUAP) ",
	"cr30(IIR)  ",
	"cr31(IBP)  ",
	"cr32(IPPU) ",
	"cr33(IPPL) ",
	"cr34(ISR)  ",
	"cr35(ILAR) ",
	"cr36(IPAR) ",
	0,0,0,
	"cr40(DCMD) ",
	"cr41(DCTL) ",
	"cr42(DSAR) ",
	"cr43(DSAP) ",
	"cr44(DUAP) ",
	"cr45(DIR)  ",
	"cr46(DBP)  ",
	"cr47(DPPU) ",
	"cr48(DPPL) ",
	"cr49(DSR)  ",
	"cr50(DLAR) ",
	"cr51(DPAR) ",
	0,0,0,0,0,0,0,0,0,0,
	"fcr62(FPSR)",
	"fcr63(FPCR)"
};

#define printval(x) \
	do { \
		if ((x) < 0) \
			db_printf("-0x%X", -(x)); \
		else \
			db_printf("0x%X", (x));	\
	} while (0)

/* prototypes */
void oimmed(int, char *, long);
void ctrlregs(int, char *, long);
void printsod(int);
void sindou(int, char *, long);
void jump(int, char *, long);
void instset(int, char *, long);
void symofset(int, int, int);
void obranch(int, char *, long);
void brcond(int, char *, long);
void otrap(int, char *, long);
void obit(int, char *, long);
void bitman(int, char *, long);
void immem(int, char *, long);
void nimmem(int, char *, long);
void lognim(int, char *, long);
void onimmed(int, char *, long);      

/* Handlers immediate integer arithmetic instructions */
void
oimmed(int inst, char  *opcode, long iadr)
{
	register int Linst = inst & 0177777;
	register int Hinst = inst >> 16;
	register int H6inst = Hinst >> 10;
	register int rs1 = Hinst & 037;
	register int rd = ( Hinst >> 5 ) & 037;

	if (( H6inst > 017 ) && ( H6inst < 030 ) && ( H6inst & 01) == 1 )
		db_printf("\t%s.u",opcode);
	else {
		db_printf("\t%s",opcode);
		db_printf("  ");
	}
	db_printf("\t\tr%-3d,r%-3d,", rd, rs1);
	printval(Linst);
}


/* Handles instructions dealing with control registers */
void
ctrlregs(int inst, char *opcode, long iadr)
{
	register int L6inst = (inst >> 11) & 037;
	register int creg = (inst >> 5) & 077;
	register int rd = (inst >> 21) & 037;
	register int rs1 = (inst >> 16) & 037;

	db_printf("\t%s",opcode);

	if ( L6inst == 010 || L6inst == 011 )
		db_printf("\t\tr%-3d,%s", rd, 
			  cputyp == CPU_88100 ? m88100_ctrlreg[creg] : m88110_ctrlreg[creg]);
	else if ( L6inst == 020 || L6inst == 021 )
		db_printf("\t\tr%-3d,%s", rs1, 
			  cputyp == CPU_88100 ? m88100_ctrlreg[creg] : m88110_ctrlreg[creg]);
	else
		db_printf("\t\tr%-3d,r%-3d,%s", rd, rs1,
			  cputyp == CPU_88100 ? m88100_ctrlreg[creg] : m88110_ctrlreg[creg]);
}


void
printsod(int t)
{
	if ( t == 0 )
		db_printf("s");
	else
		db_printf("d");
}

/* Handles floating point instructions */
void
sindou(int inst, char *opcode, long iadr)
{
	register int rs2 = inst & 037;
	register int td = ( inst >> 5 ) & 03;
	register int t2 = ( inst >> 7 ) & 03;
	register int t1 = ( inst >> 9 ) & 03;
	register int rs1 = ( inst >> 16 ) & 037;
	register int rd = ( inst >> 21 ) & 037;
	register int checkbits  = ( inst >> 11 ) & 037;

	db_printf("\t%s.",opcode);
	printsod(td);
	if (( checkbits > 010 && checkbits < 014 ) || ( checkbits == 04 )) {
		printsod(t2);
		db_printf(" ");
		if ( checkbits == 012 || checkbits == 013 )
			db_printf("\t\tr%-3d,r%-3d", rd, rs2);
		else
			db_printf("\t\tr%-3d,r%-3d", rd, rs2);
	} else {
		printsod(t1);printsod(t2);
		db_printf("\t\tr%-3d,r%-3d,r%-3d", rd, rs1, rs2);
	}
}


void
jump(int inst, char *opcode, long iadr)
{
	register int rs2 = inst & 037;
	register int Nbit = ( inst >> 10 ) & 01;

	db_printf("\t%s",opcode);
	if ( Nbit == 1 )
		db_printf(".n");
	else
		db_printf("  ");
	db_printf("\t\tr%-3d",rs2);
}


/* Handles ff1, ff0, tbnd and rte instructions */ 
void
instset(int inst, char *opcode, long iadr)
{
	register int rs2 = inst & 037;
	register int rs1 = ( inst >> 16 ) & 037;
	register int rd = ( inst >> 21 ) & 037;
	register int checkbits = ( inst >> 10 ) & 077;
	register int H6inst = ( inst >> 26 ) & 077;

	db_printf("\t%s",opcode);
	if ( H6inst == 076 ) {
		db_printf("\t\tr%-3d,",rs1);
		printval(inst & 0177777);
	} else if (( checkbits == 072 ) || ( checkbits == 073 ))
		db_printf("\t\tr%-3d,r%-3d", rd, rs2);
	else if ( checkbits == 076 )
		db_printf("\t\tr%-3d,r%-3d",rs1,rs2);
}

void
symofset(int  disp, int  bit, int iadr)
{
	long addr;

	if ( disp & (1 << (bit-1)) ) {
		/* negative value */
		addr = iadr + ((disp << 2) | (~0 << bit));
	} else {
		addr = iadr + (disp << 2);
	}
	db_printsym(addr,DB_STGY_PROC);
	return;
}

void
obranch(int inst, char *opcode, long iadr)
{
	int cond = ( inst >> 26 ) & 01;
	int disp = inst &0377777777;

	if ( cond == 0 ) {
		db_printf("\t%s\t\t",opcode);
		symofset(disp, 26, iadr);
	} else {
		db_printf("\t%s.n\t\t",opcode);
		symofset(disp, 26, iadr);
	}
}


/* Handles branch on conditions instructions */
void
brcond(int inst, char *opcode, long iadr)
{
	int cond = ( inst >> 26 ) & 1;
	int match = ( inst >> 21 ) & 037;
	int rs = ( inst >> 16 ) & 037;
	int disp = ( inst & 0177777 );

	if ( cond == 0 )
		db_printf("\t%s\t\t", opcode);
	else
		db_printf("\t%s.n\t\t", opcode);
	if ( ( ( inst >> 27 ) & 03 ) == 1 )
		switch (match) {
		case 1 : db_printf("%s,", condname[0]); break;
		case 2 : db_printf("%s,", condname[1]); break;
		case 3 : db_printf("%s,", condname[2]); break;
		case 12: db_printf("%s,", condname[3]); break;
		case 13: db_printf("%s,", condname[4]); break;
		case 14: db_printf("%s,", condname[5]); break;
		default: printval(match); 
			db_printf(",");
		} else {
		printval(match);
		db_printf(",");
	}

	db_printf("r%-3d,", rs);
	symofset(disp, 16, iadr);
}


void
otrap(int inst, char *opcode, long iadr)
{
	int vecno = inst & 0777;
	int match = ( inst >> 21 ) & 037;
	int rs = ( inst >> 16 ) & 037;

	db_printf("\t%s\t",opcode);
	if ( ( ( inst >> 12 ) & 017 ) == 0xe )
		switch (match) {
		case 1 : db_printf("%s,", condname[0]);break;
		case 2 : db_printf("%s,", condname[1]);break;
		case 3 : db_printf("%s,", condname[2]);break;
		case 12: db_printf("%s,", condname[3]);break;
		case 13: db_printf("%s,", condname[4]);break;
		case 14: db_printf("%s,", condname[5]);break;
		default: printval(match);
			db_printf(",");
		} else {
		printval(match);
		db_printf(",");
	}
	db_printf("\tr%-3d,", rs);
	printval(vecno);
}


/* Handles 10 bit immediate bit field operations */
void
obit(int inst, char *opcode, long iadr)
{
	int rs = ( inst >> 16 ) & 037;
	int rd = ( inst >> 21 ) & 037;
	int width = ( inst >> 5 ) & 037;
	int offset = ( inst & 037 );  

	db_printf("\t%s\t\tr%-3d,r%-3d,", opcode, rd, rs); 
	if ( ( ( inst >> 10 ) & 077 ) == 052 ) {
		db_printf("<"); 
		printval(offset); 
		db_printf(">"); 
	} else {
		printval(width);
		db_printf("<");
		printval(offset);
		db_printf(">");
	}
}


/* Handles triadic mode bit field instructions */
void
bitman(int inst, char *opcode, long iadr)
{

	int rs1 = ( inst >> 16 ) & 037;
	int rd  = ( inst >> 21 ) & 037;
	int rs2 = inst & 037;

	db_printf("\t%s\t\tr%-3d,r%-3d,r%-3d", opcode, rd, rs1, rs2);
}


/* Handles immediate load/store/exchange instructions */
void
immem(int inst, char *opcode, long iadr)
{
	register int immed  = inst & 0xFFFF;
	register int rd     = (inst >> 21) & 037;
	register int rs     = (inst >> 16) & 037;
	register int st_lda = (inst >> 28) & 03;
	register int aryno  = (inst >> 26) & 03;
	char c = ' ';

	if (!st_lda) {
		if ((aryno == 0) || (aryno == 01))
			opcode = "xmem";
		else
			opcode = "ld";
		if (aryno == 0)
			aryno = 03;
		if (!(aryno == 01))
			c = 'u';
	} else
		if (st_lda == 01)
		opcode = "ld";

	db_printf("\t%s%s%c\t\tr%-3d,r%-3d,", opcode, instwidth[aryno], 
		  c, rd, rs);
	printval(immed);
}


/* Handles triadic mode load/store/exchange instructions */
void
nimmem(int inst, char *opcode, long iadr)
{
	register int scaled  = (inst >> 9) & 01;
	register int rd      = (inst >> 21) & 037;
	register int rs1     = (inst >> 16) & 037;
	register int rs2     = inst & 037;
	register int st_lda  = (inst >> 12) & 03;
	register int aryno   = (inst >> 10) & 03;
	register int user_bit = 0;
	int signed_fg  = 1;
	char *user           = "    ";
	char c = ' ';

	if (!st_lda) {
		if ((aryno == 0) || (aryno == 01))
			opcode = "xmem";
		else
			opcode = "ld";
		if (aryno == 0)
			aryno = 03;
		if (!(aryno == 01)) {
			c = 'u';
			signed_fg = 0;
		}
	} else
		if (st_lda == 01)
		opcode = "ld";

	if (!(st_lda == 03)) {
		user_bit = (inst >> 8) & 01;
		if (user_bit)
			user = ".usr";
	}

	if (user_bit && signed_fg && (aryno == 01)) {
		if (st_lda)
			db_printf("\t%s%s\tr%-3d,r%-3d", opcode,
				  user, rd, rs1);
		else
			db_printf("\t%s%s\tr%-3d,r%-3d", opcode,
				  user, rd, rs1);
	} else
		if (user_bit && signed_fg)
		db_printf("\t%s%s%s\tr%-3d,r%-3d", opcode, 
			  instwidth[aryno], user, rd, rs1);
	else
		db_printf("\t%s%s%c%s\tr%-3d,r%-3d", opcode, 
			  instwidth[aryno], c, user, rd, rs1);

	if (scaled)
		db_printf("[r%-3d]", rs2);
	else
		db_printf(",r%-3d", rs2);
}


/* Handles triadic mode logical instructions */
void
lognim(int inst, char *opcode, long iadr)
{
	register int rd   = (inst >> 21) & 037;
	register int rs1  = (inst >> 16) & 037;
	register int rs2  = inst & 037;
	register int complemt = (inst >> 10) & 01;
	char *c = "  ";

	if (complemt)
		c = ".c";

	db_printf("\t%s%s\t\tr%-3d,r%-3d,r%-3d", opcode, c, rd, rs1, rs2);
}


/* Handles triadic mode arithmetic instructions */
void
onimmed(int inst, char *opcode, long iadr)
{
	register int rd   = (inst >> 21) & 037;
	register int rs1  = (inst >> 16) & 037;
	register int rs2  = inst & 037;
	register int carry = (inst >> 8) & 03;
	register int nochar = (inst >> 10) & 07;
	register int nodecode = (inst >> 11) & 01;
	char *tab, *c ;

	if (nochar > 02)
		tab = "\t\t";
	else
		tab = "\t";

	if (!nodecode) {
		if (carry == 01)
			c = ".co ";
		else
			if (carry == 02)
			c = ".ci ";
		else
			if (carry == 03)
			c = ".cio";
		else
			c = "    ";
	} else
		c = "    ";

	db_printf("\t%s%s%sr%-3d,r%-3d,r%-3d", opcode, c,
		  tab, rd, rs1, rs2);
}

static struct opdesc {
	unsigned mask, match;
	void (*opfun)(int, char *, long);
	char *farg;
} opdecode[] = {

	/* ORDER IS IMPORTANT BELOW */

	{   0xF0000000U, 0x00000000U, immem, 0,},
	{   0xF0000000U, 0x10000000U, immem, 0,},
	{   0xF0000000U, 0x20000000U, immem, "st"},
	{   0xF0000000U, 0x30000000U, immem, "lda"},

	{   0xF8000000U, 0x40000000U, oimmed, "and"},
	{   0xF8000000U, 0x48000000U, oimmed, "mask"},
	{   0xF8000000U, 0x50000000U, oimmed, "xor"},
	{   0xF8000000U, 0x58000000U, oimmed, "or"},
	{   0xFC000000U, 0x60000000U, oimmed, "addu"},
	{   0xFC000000U, 0x64000000U, oimmed, "subu"},
	{   0xFC000000U, 0x68000000U, oimmed, "divu"},
	{   0xFC000000U, 0x6C000000U, oimmed, "mul"},
	{   0xFC000000U, 0x70000000U, oimmed, "add"},
	{   0xFC000000U, 0x74000000U, oimmed, "sub"},
	{   0xFC000000U, 0x78000000U, oimmed, "div"},
	{   0xFC000000U, 0x7C000000U, oimmed, "cmp"},

	{   0xFC00F800U, 0x80004000U, ctrlregs, "ldcr"},
	{   0xFC00F800U, 0x80004800U, ctrlregs, "fldcr"},
	{   0xFC00F800U, 0x80008000U, ctrlregs, "stcr"},
	{   0xFC00F800U, 0x80008800U, ctrlregs, "fstcr"},
	{   0xFC00F800U, 0x8000C000U, ctrlregs, "xcr"},
	{   0xFC00F800U, 0x8000C800U, ctrlregs, "fxcr"},

	{   0xFC00F800U, 0x84000000U, sindou, "fmul"},
	{   0xFC1FFF80U, 0x84002000U, sindou, "flt"},
	{   0xFC00F800U, 0x84002800U, sindou, "fadd"},
	{   0xFC00F800U, 0x84003000U, sindou, "fsub"},
	{   0xFC00F860U, 0x84003800U, sindou, "fcmp"},
	{   0xFC1FFE60U, 0x84004800U, sindou, "int"},
	{   0xFC1FFE60U, 0x84005000U, sindou, "nint"},
	{   0xFC1FFE60U, 0x84005800U, sindou, "trnc"},
	{   0xFC00F800U, 0x84007000U, sindou, "fdiv"},

	{   0xF8000000U, 0xC0000000U, obranch, "br"},
	{   0xF8000000U, 0xC8000000U, obranch, "bsr"},

	{   0xF8000000U, 0xD0000000U, brcond, "bb0"},
	{   0xF8000000U, 0xD8000000U, brcond, "bb1"},
	{   0xF8000000U, 0xE8000000U, brcond, "bcnd"},

	{   0xFC00FC00U, 0xF0008000U, obit, "clr"},
	{   0xFC00FC00U, 0xF0008800U, obit, "set"},
	{   0xFC00FC00U, 0xF0009000U, obit, "ext"},
	{   0xFC00FC00U, 0xF0009800U, obit, "extu"},
	{   0xFC00FC00U, 0xF000A000U, obit, "mak"},
	{   0xFC00FC00U, 0xF000A800U, obit, "rot"},

	{   0xFC00FE00U, 0xF000D000U, otrap, "tb0"},
	{   0xFC00FE00U, 0xF000D800U, otrap, "tb1"},
	{   0xFC00FE00U, 0xF000E800U, otrap, "tcnd"},

	{   0xFC00F2E0U, 0xF4000000U, nimmem, 0,},
	{   0xFC00F2E0U, 0xF4000200U, nimmem, 0,},
	{   0xFC00F2E0U, 0xF4001000U, nimmem, 0,},
	{   0xFC00F2E0U, 0xF4001200U, nimmem, 0,},
	{   0xFC00F2E0U, 0xF4002000U, nimmem, "st"},
	{   0xFC00F2E0U, 0xF4002200U, nimmem, "st"},
	{   0xFC00F2E0U, 0xF4003000U, nimmem, "lda"},
	{   0xFC00F2E0U, 0xF4003200U, nimmem, "lda"},

	{   0xFC00FBE0U, 0xF4004000U, lognim, "and"},
	{   0xFC00FBE0U, 0xF4005000U, lognim, "xor"},
	{   0xFC00FBE0U, 0xF4005800U, lognim, "or"},

	{   0xFC00FCE0U, 0xF4006000U, onimmed, "addu"},
	{   0xFC00FCE0U, 0xF4006400U, onimmed, "subu"},
	{   0xFC00FCE0U, 0xF4006800U, onimmed, "divu"},
	{   0xFC00FCE0U, 0xF4006C00U, onimmed, "mul"},
	{   0xFC00FCE0U, 0xF4007000U, onimmed, "add"},
	{   0xFC00FCE0U, 0xF4007400U, onimmed, "sub"},
	{   0xFC00FCE0U, 0xF4007800U, onimmed, "div"},
	{   0xFC00FCE0U, 0xF4007C00U, onimmed, "cmp"},

	{   0xFC00FFE0U, 0xF4008000U, bitman, "clr"},
	{   0xFC00FFE0U, 0xF4008800U, bitman, "set"},
	{   0xFC00FFE0U, 0xF4009000U, bitman, "ext"},
	{   0xFC00FFE0U, 0xF4009800U, bitman, "extu"},
	{   0xFC00FFE0U, 0xF400A000U, bitman, "mak"},
	{   0xFC00FFE0U, 0xF400A800U, bitman, "rot"},

	{   0xFC00FBE0U, 0xF400C000U, jump, "jmp"},
	{   0xFC00FBE0U, 0xF400C800U, jump, "jsr"},

	{   0xFC00FFE0U, 0xF400E800U, instset, "ff1"},
	{   0xFC00FFE0U, 0xF400EC00U, instset, "ff0"},
	{   0xFC00FFE0U, 0xF400F800U, instset, "tbnd"},
	{   0xFC00FFE0U, 0xF400FC00U, instset, "rte"},
	{   0xFC000000U, 0xF8000000U, instset, "tbnd"},
	{   0,0,0,0}
};

static char *badop = "\t???";

int
m88k_print_instruction(unsigned iadr, long inst)
{
	register struct opdesc *p;

	/* this messes up "orb" instructions ever so slightly, */
	/* but keeps us in sync between routines... */
	if (inst == 0) {
		db_printf ("\t.word 0");
	} else {
		for (p = opdecode; p->mask; p++)
			if ((inst & p->mask) == p->match) {
				(*p->opfun) (inst, p->farg, iadr);
				break;
			}
		if (!p->mask)
			db_printf (badop);
	}

	return iadr+4;
}

db_addr_t
db_disasm(db_addr_t loc, boolean_t altfmt)
{
	m88k_print_instruction(loc, db_get_value(loc, 4, FALSE));
	db_printf ("\n");
	return loc+4;
}