7db.c

这是一个同样来自贝尔实验室的和UNIX有着渊源的操作系统, 其简洁的设计和实现易于我们学习和理解

	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,

	"CVTLQ",	0,	alphafp2,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,

	"CPYS",		0,	alphafp,
	"CPYSN",	0,	alphafp,
	"CPYSE",	0,	alphafp,
	"???",		0,	alphaxxx,
	"MOVT",		0,	"FPCR,F%a",
	"MOVT",		0,	"F%a,FPCR",
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"FCMOVEQ",	0,	alphafp,
	"FCMOVNE",	0,	alphafp,
	"FCMOVLT",	0,	alphafp,
	"FCMOVGE",	0,	alphafp,
	"FCMOVLE",	0,	alphafp,
	"FCMOVGT",	0,	alphafp,

	"CVTQL",	0,	alphafp2,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
};

static Opcode ieeeopcodes[64] = {
	"ADDS",		0,	alphafp,
	"SUBS",		0,	alphafp,
	"MULS",		0,	alphafp,
	"DIVS",		0,	alphafp,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,

	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,

	"ADDT",		0,	alphafp,
	"SUBT",		0,	alphafp,
	"MULT",		0,	alphafp,
	"DIVT",		0,	alphafp,
	"CMPTUN",	0,	alphafp,
	"CMPTEQ",	0,	alphafp,
	"CMPTLT",	0,	alphafp,
	"CMPTLE",	0,	alphafp,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"CVTTS",	0,	alphafp2,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"CVTTQ",	0,	alphafp2,

	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"???",		0,	alphaxxx,
	"CVTQS",	0,	alphafp2,
	"???",		0,	alphaxxx,
	"CVTQT",	0,	alphafp2,
	"???",		0,	alphaxxx,
};

static uchar	amap[128] = {
	[0x00]	1,
	[0x40]	2,
	[0x20]	3,
	[0x60]	4,
	[0x09]	5,
	[0x49]	6,
	[0x29]	7,
	[0x69]	8,
	[0x2D]	9,
	[0x4D]	10,
	[0x6D]	11,
	[0x1D]	12,	
	[0x3D]	13,	
	[0x0F]	14,	
	[0x02]	15,	
	[0x0B]	16,	
	[0x12]	17,	
	[0x1B]	18,
	[0x22]	19,	
	[0x2B]	20,	
	[0x32]	21,	
	[0x3B]	22,
};

static Opcode arithopcodes[64] = {
	"???",		0,	alphaxxx,
	"ADDL",		0,	alphaint,
	"ADDL/V",	0,	alphaint,
	"ADDQ",		0,	alphaint,
	"ADDQ/V",	0,	alphaint,
	"SUBL",		0,	alphaint,
	"SUBL/V",	0,	alphaint,
	"SUBQ",		0,	alphaint,
	"SUBQ/V",	0,	alphaint,
	"CMPEQ",	0,	alphaint,
	"CMPLT",	0,	alphaint,
	"CMPLE",	0,	alphaint,
	"CMPULT",	0,	alphaint,
	"CMPULE",	0,	alphaint,
	"CMPBGE",	0,	alphaint,
	"S4ADDL",	0,	alphaint,
	"S4SUBL",	0,	alphaint,
	"S8ADDL",	0,	alphaint,
	"S8SUBL",	0,	alphaint,
	"S4ADDQ",	0,	alphaint,
	"S4SUBQ",	0,	alphaint,
	"S8ADDQ",	0,	alphaint,
	"S8SUBQ",	0,	alphaint,
};

static uchar	lmap[128] = {
	[0x00]	1,
	[0x20]	2,
	[0x40]	3,
	[0x08]	4,
	[0x28]	5,
	[0x48]	6,
	[0x24]	7,
	[0x44]	8,
	[0x64]	9,
	[0x26]	7,
	[0x46]	8,
	[0x66]	9,
	[0x14]	10,
	[0x16]	11,
};

static Opcode logicalopcodes[64] = {
	"???",		0,	alphaxxx,
	"AND",		0,	alphaint,
	"OR",		0,	alphaint,
	"XOR",		0,	alphaint,
	"ANDNOT",	0,	alphaint,
	"ORNOT",	0,	alphaint,
	"XORNOT",	0,	alphaint,
	"CMOVEQ",	0,	alphaint,
	"CMOVLT",	0,	alphaint,
	"CMOVLE",	0,	alphaint,
	"CMOVNE",	0,	alphaint,
	"CMOVGE",	0,	alphaint,
	"CMOVGT",	0,	alphaint,
	"CMOVLBS",	0,	alphaint,
	"CMOVLBC",	0,	alphaint,
};

static uchar	smap[128] = {
	[0x39]	1,
	[0x3C]	2,
	[0x34]	3,
	[0x06]	4,
	[0x16]	5,
	[0x26]	6,
	[0x36]	7,
	[0x5A]	8,
	[0x6A]	9,
	[0x7A]	10,
	[0x0B]	11,
	[0x1B]	12,
	[0x2B]	13,
	[0x3B]	14,
	[0x57]	15,
	[0x67]	16,
	[0x77]	17,
	[0x02]	18,
	[0x12]	19,
	[0x22]	20,
	[0x32]	21,
	[0x52]	22,
	[0x62]	23,
	[0x72]	24,
	[0x30]	25,
	[0x31]	26,
};

static Opcode shiftopcodes[64] = {
	"???",		0,	alphaxxx,
	"SLLQ",		0,	alphaint,
	"SRAQ",		0,	alphaint,
	"SRLQ",		0,	alphaint,
	"EXTBL",	0,	alphaint,
	"EXTWL",	0,	alphaint,
	"EXTLL",	0,	alphaint,
	"EXTQL",	0,	alphaint,
	"EXTWH",	0,	alphaint,
	"EXTLH",	0,	alphaint,
	"EXTQH",	0,	alphaint,
	"INSBL",	0,	alphaint,
	"INSWL",	0,	alphaint,
	"INSLL",	0,	alphaint,
	"INSQL",	0,	alphaint,
	"INSWH",	0,	alphaint,
	"INSLH",	0,	alphaint,
	"INSQH",	0,	alphaint,
	"MSKBL",	0,	alphaint,
	"MSKWL",	0,	alphaint,
	"MSKLL",	0,	alphaint,
	"MSKQL",	0,	alphaint,
	"MSKWH",	0,	alphaint,
	"MSKLH",	0,	alphaint,
	"MSKQH",	0,	alphaint,
	"ZAP",		0,	alphaint,
	"ZAPNOT",	0,	alphaint,
};

static void
format(char *mnemonic, Instr *i, char *f)
{
	if (mnemonic)
		format(0, i, mnemonic);
	if (f == 0)
		return;
	if (mnemonic)
		if (i->curr < i->end)
			*i->curr++ = '\t';
	for ( ; *f && i->curr < i->end; f++) {
		if (*f != '%') {
			*i->curr++ = *f;
			continue;
		}
		switch (*++f) {

		case 'a':
			bprint(i, "%d", i->ra);
			break;

		case 'b':
			bprint(i, "%d", i->rb);
			break;

		case 'c':
			bprint(i, "%d", i->rc);
			break;

		case 'v':
			if (i->islit)
				bprint(i, "$%ux", i->literal);
			else
				bprint(i, "R%d", i->rb);
			break;

		case 'l':
			bprint(i, "%lx(R%d)", i->mem, i->rb);
			break;

		case 'i':
			bprint(i, "$%lx", i->mem);
			break;

		case 'B':
			i->curr += symoff(i->curr, i->end-i->curr,
				(i->branch<<2)+i->addr+4, CANY);
			break;

		case 'w':
			bprint(i, "[%lux]", i->w0);
			break;

		case '\0':
			*i->curr++ = '%';
			return;

		default:
			bprint(i, "%%%c", *f);
			break;
		}
	}
	*i->curr = 0;
}

static int
printins(Map *map, uvlong pc, char *buf, int n)
{
	Instr i;
	Opcode *o;
	uchar op;

	i.curr = buf;
	i.end = buf+n-1;
	mymap = map;
	if (mkinstr(pc, &i) < 0)
		return -1;
	switch (i.op) {

	case 0x10:					/* INTA */
		o = arithopcodes;
		op = amap[i.function];
		break;

	case 0x11:					/* INTL */
		o = logicalopcodes;
		op = lmap[i.function];
		break;

	case 0x12:					/* INTS */
		o = shiftopcodes;
		op = smap[i.function];
		break;

	case 0x16:					/* FLTI */
		o = ieeeopcodes;
		op = i.fpfn;
		break;

	case 0x17:					/* FLTL */
		o = fpopcodes;
		op = i.fpfn;
		break;

	default:
		o = opcodes;
		op = i.op;
		break;
	}
	if (o[op].f)
		(*o[op].f)(&o[op], &i);
	else
		format(o[op].mnemonic, &i, o[op].ken);
	return i.size*4;
}

static int
alphainst(Map *map, uvlong pc, char modifier, char *buf, int n)
{
	USED(modifier);
	return printins(map, pc, buf, n);
}

static int
alphadas(Map *map, uvlong pc, char *buf, int n)
{
	Instr i;

	i.curr = buf;
	i.end = buf+n;
	mymap = map;
	if (mkinstr(pc, &i) < 0)
		return -1;
	if (i.end-i.curr > 8)
		i.curr = _hexify(buf, i.w0, 7);
	if (i.size == 2 && i.end-i.curr > 9) {
		*i.curr++ = ' ';
		i.curr = _hexify(i.curr, i.w1, 7);
	}
	*i.curr = 0;
	return i.size*4;
}

static int
alphainstlen(Map *map, uvlong pc)
{
	Instr i;

	mymap = map;
	if (mkinstr(pc, &i) < 0)
		return -1;
	return i.size*4;
}

static int
alphafoll(Map *map, uvlong pc, Rgetter rget, uvlong *foll)
{
	char buf[8];
	Instr i;

	mymap = map;
	if (mkinstr(pc, &i) < 0)
		return -1;

	switch(i.op) {
	case 0x1A:				/* JMP/JSR/RET */
		sprint(buf, "R%d", i.rb);
		foll[0] = (*rget)(map, buf);
		return 1;
	case 0x30:				/* BR */
	case 0x34:				/* BSR */
		foll[0] = pc+4 + (i.branch<<2);
		return 1;
	default:
		if (i.op > 0x30) {		/* cond */
			foll[0] = pc+4;
			foll[1] = pc+4 + (i.branch<<2);
			return 2;
		}
		foll[0] = pc+i.size*4;
		return 1;
	}
}