txt.c

来自「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」· C语言 代码 · 共 1,409 行 · 第 1/2 页

	case CASE(	TUINT,	TINT):
	case CASE(	TLONG,	TINT):
	case CASE(	TULONG,	TINT):
	case CASE(	TIND,	TINT):

	case CASE(	TINT,	TUINT):
	case CASE(	TUINT,	TUINT):
	case CASE(	TLONG,	TUINT):
	case CASE(	TULONG,	TUINT):
	case CASE(	TIND,	TUINT):

	case CASE(	TINT,	TLONG):
	case CASE(	TUINT,	TLONG):
	case CASE(	TLONG,	TLONG):
	case CASE(	TULONG,	TLONG):
	case CASE(	TIND,	TLONG):

	case CASE(	TINT,	TULONG):
	case CASE(	TUINT,	TULONG):
	case CASE(	TLONG,	TULONG):
	case CASE(	TULONG,	TULONG):
	case CASE(	TIND,	TULONG):

	case CASE(	TINT,	TIND):
	case CASE(	TUINT,	TIND):
	case CASE(	TLONG,	TIND):
	case CASE(	TULONG,	TIND):
	case CASE(	TIND,	TIND):
 *****/
		a = AMOVL;
		break;

	case CASE(	TSHORT,	TINT):
	case CASE(	TSHORT,	TUINT):
	case CASE(	TSHORT,	TLONG):
	case CASE(	TSHORT,	TULONG):
	case CASE(	TSHORT,	TIND):
		a = AMOVWLSX;
		if(f->op == OCONST) {
			f->vconst &= 0xffff;
			if(f->vconst & 0x8000)
				f->vconst |= 0xffff0000;
			a = AMOVL;
		}
		break;

	case CASE(	TUSHORT,TINT):
	case CASE(	TUSHORT,TUINT):
	case CASE(	TUSHORT,TLONG):
	case CASE(	TUSHORT,TULONG):
	case CASE(	TUSHORT,TIND):
		a = AMOVWLZX;
		if(f->op == OCONST) {
			f->vconst &= 0xffff;
			a = AMOVL;
		}
		break;

	case CASE(	TCHAR,	TSHORT):
	case CASE(	TCHAR,	TUSHORT):
	case CASE(	TCHAR,	TINT):
	case CASE(	TCHAR,	TUINT):
	case CASE(	TCHAR,	TLONG):
	case CASE(	TCHAR,	TULONG):
	case CASE(	TCHAR,	TIND):
		a = AMOVBLSX;
		if(f->op == OCONST) {
			f->vconst &= 0xff;
			if(f->vconst & 0x80)
				f->vconst |= 0xffffff00;
			a = AMOVL;
		}
		break;

	case CASE(	TUCHAR,	TSHORT):
	case CASE(	TUCHAR,	TUSHORT):
	case CASE(	TUCHAR,	TINT):
	case CASE(	TUCHAR,	TUINT):
	case CASE(	TUCHAR,	TLONG):
	case CASE(	TUCHAR,	TULONG):
	case CASE(	TUCHAR,	TIND):
		a = AMOVBLZX;
		if(f->op == OCONST) {
			f->vconst &= 0xff;
			a = AMOVL;
		}
		break;

/*
 * float to fix
 */
	case CASE(	TFLOAT,	TCHAR):
	case CASE(	TFLOAT,	TUCHAR):
	case CASE(	TFLOAT,	TSHORT):
	case CASE(	TFLOAT,	TUSHORT):
	case CASE(	TFLOAT,	TINT):
	case CASE(	TFLOAT,	TLONG):
	case CASE(	TFLOAT,	TIND):

	case CASE(	TDOUBLE,TCHAR):
	case CASE(	TDOUBLE,TUCHAR):
	case CASE(	TDOUBLE,TSHORT):
	case CASE(	TDOUBLE,TUSHORT):
	case CASE(	TDOUBLE,TINT):
	case CASE(	TDOUBLE,TLONG):
	case CASE(	TDOUBLE,TIND):
		if(fproundflg) {
			regsalloc(&nod, &regnode);
			gins(AFMOVLP, f, &nod);
			gmove(&nod, t);
			return;
		}
		regsalloc(&nod, &regnode);
		regsalloc(&nod1, &regnode);
		gins(AFSTCW, Z, &nod1);
		nod1.xoffset += 2;
		gins(AMOVW, nodconst(0xf7f), &nod1);
		gins(AFLDCW, &nod1, Z);
		gins(AFMOVLP, f, &nod);
		nod1.xoffset -= 2;
		gins(AFLDCW, &nod1, Z);
		gmove(&nod, t);
		return;

/*
 * float to ulong
 */
	case CASE(	TDOUBLE,	TULONG):
	case CASE(	TFLOAT,	TULONG):
	case CASE(	TDOUBLE,	TUINT):
	case CASE(	TFLOAT,	TUINT):
		regsalloc(&nod, &regnode);
		gmove(f, &fregnode0);
		gins(AFADDD, nodfconst(-2147483648.), &fregnode0);
		gins(AFMOVLP, f, &nod);
		gins(ASUBL, nodconst(-2147483648), &nod);
		gmove(&nod, t);
		return;

/*
 * ulong to float
 */
	case CASE(	TULONG,	TDOUBLE):
	case CASE(	TULONG,	TFLOAT):
	case CASE(	TUINT,	TDOUBLE):
	case CASE(	TUINT,	TFLOAT):
		regalloc(&nod, f, f);
		gmove(f, &nod);
		regsalloc(&nod1, &regnode);
		gmove(&nod, &nod1);
		gins(AFMOVL, &nod1, &fregnode0);
		gins(ACMPL, &nod, nodconst(0));
		gins(AJGE, Z, Z);
		p1 = p;
		gins(AFADDD, nodfconst(4294967296.), &fregnode0);
		patch(p1, pc);
		regfree(&nod);
		return;

/*
 * fix to float
 */
	case CASE(	TCHAR,	TFLOAT):
	case CASE(	TUCHAR,	TFLOAT):
	case CASE(	TSHORT,	TFLOAT):
	case CASE(	TUSHORT,TFLOAT):
	case CASE(	TINT,	TFLOAT):
	case CASE(	TLONG,	TFLOAT):
	case CASE(	TIND,	TFLOAT):

	case CASE(	TCHAR,	TDOUBLE):
	case CASE(	TUCHAR,	TDOUBLE):
	case CASE(	TSHORT,	TDOUBLE):
	case CASE(	TUSHORT,TDOUBLE):
	case CASE(	TINT,	TDOUBLE):
	case CASE(	TLONG,	TDOUBLE):
	case CASE(	TIND,	TDOUBLE):
		regsalloc(&nod, &regnode);
		gmove(f, &nod);
		gins(AFMOVL, &nod, &fregnode0);
		return;

/*
 * float to float
 */
	case CASE(	TFLOAT,	TFLOAT):
	case CASE(	TDOUBLE,TFLOAT):

	case CASE(	TFLOAT,	TDOUBLE):
	case CASE(	TDOUBLE,TDOUBLE):
		a = AFMOVD;	break;
	}
	if(a == AMOVL || a == AFMOVD)
	if(samaddr(f, t))
		return;
	gins(a, f, t);
}

void
doindex(Node *n)
{
	Node nod, nod1;
	long v;

if(debug['Y'])
prtree(n, "index");

if(n->left->complex >= FNX)
print("botch in doindex\n");

	regalloc(&nod, &regnode, Z);
	v = constnode.vconst;
	cgen(n->right, &nod);
	idx.ptr = D_NONE;
	if(n->left->op == OCONST)
		idx.ptr = D_CONST;
	else if(n->left->op == OREGISTER)
//	else if(n->left->op == OREGISTER && typeil[n->left->type->etype])
		idx.ptr = n->left->reg;
	else if(n->left->op != OADDR) {
		reg[D_BP]++;	// cant be used as a base
		regalloc(&nod1, &regnode, Z);
		cgen(n->left, &nod1);
		idx.ptr = nod1.reg;
		regfree(&nod1);
		reg[D_BP]--;
	}
	idx.reg = nod.reg;
	regfree(&nod);
	constnode.vconst = v;
}

void
gins(int a, Node *f, Node *t)
{

	if(f != Z && f->op == OINDEX)
		doindex(f);
	if(t != Z && t->op == OINDEX)
		doindex(t);
	nextpc();
	p->as = a;
	if(f != Z)
		naddr(f, &p->from);
	if(t != Z)
		naddr(t, &p->to);
	if(debug['g'])
		print("%P\n", p);
}

void
fgopcode(int o, Node *f, Node *t, int pop, int rev)
{
	int a, et;
	Node nod;

	et = TLONG;
	if(f != Z && f->type != T)
		et = f->type->etype;
	if(!typefd[et]) {
		diag(f, "fop: integer %O", o);
		return;
	}
	if(debug['M']) {
		if(t != Z && t->type != T)
			print("gop: %O %O-%s Z\n", o, f->op, tnames[et]);
		else
			print("gop: %O %O-%s %O-%s\n", o,
				f->op, tnames[et], t->op, tnames[t->type->etype]);
	}
	a = AGOK;
	switch(o) {

	case OASADD:
	case OADD:
		if(et == TFLOAT)
			a = AFADDF;
		else
		if(et == TDOUBLE || et == TVLONG) {
			a = AFADDD;
			if(pop)
				a = AFADDDP;
		}
		break;

	case OASSUB:
	case OSUB:
		if(et == TFLOAT) {
			a = AFSUBF;
			if(rev)
				a = AFSUBRF;
		} else
		if(et == TDOUBLE || et == TVLONG) {
			a = AFSUBD;
			if(pop)
				a = AFSUBDP;
			if(rev) {
				a = AFSUBRD;
				if(pop)
					a = AFSUBRDP;
			}
		}
		break;

	case OASMUL:
	case OMUL:
		if(et == TFLOAT)
			a = AFMULF;
		else
		if(et == TDOUBLE || et == TVLONG) {
			a = AFMULD;
			if(pop)
				a = AFMULDP;
		}
		break;

	case OASMOD:
	case OMOD:
	case OASDIV:
	case ODIV:
		if(et == TFLOAT) {
			a = AFDIVF;
			if(rev)
				a = AFDIVRF;
		} else
		if(et == TDOUBLE || et == TVLONG) {
			a = AFDIVD;
			if(pop)
				a = AFDIVDP;
			if(rev) {
				a = AFDIVRD;
				if(pop)
					a = AFDIVRDP;
			}
		}
		break;

	case OEQ:
	case ONE:
	case OLT:
	case OLE:
	case OGE:
	case OGT:
		pop += rev;
		if(et == TFLOAT) {
			a = AFCOMF;
			if(pop) {
				a = AFCOMFP;
				if(pop > 1)
					a = AGOK;
			}
		} else
		if(et == TDOUBLE || et == TVLONG) {
			a = AFCOMF;
			if(pop) {
				a = AFCOMDP;
				if(pop > 1)
					a = AFCOMDPP;
			}
		}
		gins(a, f, t);
		regalloc(&nod, &regnode, Z);
		if(nod.reg != D_AX) {
			regfree(&nod);
			nod.reg = D_AX;
			gins(APUSHL, &nod, Z);
			gins(AWAIT, Z, Z);
			gins(AFSTSW, Z, &nod);
			gins(ASAHF, Z, Z);
			gins(APOPL, Z, &nod);
		} else {
			gins(AWAIT, Z, Z);
			gins(AFSTSW, Z, &nod);
			gins(ASAHF, Z, Z);
			regfree(&nod);
		}
		switch(o) {
		case OEQ:	a = AJEQ; break;
		case ONE:	a = AJNE; break;
		case OLT:	a = AJCS; break;
		case OLE:	a = AJLS; break;
		case OGE:	a = AJCC; break;
		case OGT:	a = AJHI; break;
		}
		gins(a, Z, Z);
		return;
	}
	if(a == AGOK)
		diag(Z, "bad in gopcode %O", o);
	gins(a, f, t);
}

void
gopcode(int o, Type *ty, Node *f, Node *t)
{
	int a, et;

	et = TLONG;
	if(ty != T)
		et = ty->etype;
	if(typefd[et] && o != OADDR && o != OFUNC) {
		diag(f, "gop: float %O", o);
		return;
	}
	if(debug['M']) {
		if(f != Z && f->type != T)
			print("gop: %O %O[%s],", o, f->op, tnames[et]);
		else
			print("gop: %O Z,", o);
		if(t != Z && t->type != T)
			print("%O[%s]\n", t->op, tnames[t->type->etype]);
		else
			print("Z\n");
	}
	a = AGOK;
	switch(o) {
	case OCOM:
		a = ANOTL;
		if(et == TCHAR || et == TUCHAR)
			a = ANOTB;
		if(et == TSHORT || et == TUSHORT)
			a = ANOTW;
		break;

	case ONEG:
		a = ANEGL;
		if(et == TCHAR || et == TUCHAR)
			a = ANEGB;
		if(et == TSHORT || et == TUSHORT)
			a = ANEGW;
		break;

	case OADDR:
		a = ALEAL;
		break;

	case OASADD:
	case OADD:
		a = AADDL;
		if(et == TCHAR || et == TUCHAR)
			a = AADDB;
		if(et == TSHORT || et == TUSHORT)
			a = AADDW;
		break;

	case OASSUB:
	case OSUB:
		a = ASUBL;
		if(et == TCHAR || et == TUCHAR)
			a = ASUBB;
		if(et == TSHORT || et == TUSHORT)
			a = ASUBW;
		break;

	case OASOR:
	case OOR:
		a = AORL;
		if(et == TCHAR || et == TUCHAR)
			a = AORB;
		if(et == TSHORT || et == TUSHORT)
			a = AORW;
		break;

	case OASAND:
	case OAND:
		a = AANDL;
		if(et == TCHAR || et == TUCHAR)
			a = AANDB;
		if(et == TSHORT || et == TUSHORT)
			a = AANDW;
		break;

	case OASXOR:
	case OXOR:
		a = AXORL;
		if(et == TCHAR || et == TUCHAR)
			a = AXORB;
		if(et == TSHORT || et == TUSHORT)
			a = AXORW;
		break;

	case OASLSHR:
	case OLSHR:
		a = ASHRL;
		if(et == TCHAR || et == TUCHAR)
			a = ASHRB;
		if(et == TSHORT || et == TUSHORT)
			a = ASHRW;
		break;

	case OASASHR:
	case OASHR:
		a = ASARL;
		if(et == TCHAR || et == TUCHAR)
			a = ASARB;
		if(et == TSHORT || et == TUSHORT)
			a = ASARW;
		break;

	case OASASHL:
	case OASHL:
		a = ASALL;
		if(et == TCHAR || et == TUCHAR)
			a = ASALB;
		if(et == TSHORT || et == TUSHORT)
			a = ASALW;
		break;

	case OFUNC:
		a = ACALL;
		break;

	case OASMUL:
	case OMUL:
		if(f->op == OREGISTER && t != Z && isreg(t, D_AX) && reg[D_DX] == 0)
			t = Z;
		a = AIMULL;
		break;

	case OASMOD:
	case OMOD:
	case OASDIV:
	case ODIV:
		a = AIDIVL;
		break;

	case OASLMUL:
	case OLMUL:
		a = AMULL;
		break;

	case OASLMOD:
	case OLMOD:
	case OASLDIV:
	case OLDIV:
		a = ADIVL;
		break;

	case OEQ:
	case ONE:
	case OLT:
	case OLE:
	case OGE:
	case OGT:
	case OLO:
	case OLS:
	case OHS:
	case OHI:
		a = ACMPL;
		if(et == TCHAR || et == TUCHAR)
			a = ACMPB;
		if(et == TSHORT || et == TUSHORT)
			a = ACMPW;
		gins(a, f, t);
		switch(o) {
		case OEQ:	a = AJEQ; break;
		case ONE:	a = AJNE; break;
		case OLT:	a = AJLT; break;
		case OLE:	a = AJLE; break;
		case OGE:	a = AJGE; break;
		case OGT:	a = AJGT; break;
		case OLO:	a = AJCS; break;
		case OLS:	a = AJLS; break;
		case OHS:	a = AJCC; break;
		case OHI:	a = AJHI; break;
		}
		gins(a, Z, Z);
		return;
	}
	if(a == AGOK)
		diag(Z, "bad in gopcode %O", o);
	gins(a, f, t);
}

int
samaddr(Node *f, Node *t)
{

	if(f->op != t->op)
		return 0;
	switch(f->op) {

	case OREGISTER:
		if(f->reg != t->reg)
			break;
		return 1;
	}
	return 0;
}

void
gbranch(int o)
{
	int a;

	a = AGOK;
	switch(o) {
	case ORETURN:
		a = ARET;
		break;
	case OGOTO:
		a = AJMP;
		break;
	}
	nextpc();
	if(a == AGOK) {
		diag(Z, "bad in gbranch %O",  o);
		nextpc();
	}
	p->as = a;
}

void
patch(Prog *op, long pc)
{

	op->to.offset = pc;
	op->to.type = D_BRANCH;
}

void
gpseudo(int a, Sym *s, Node *n)
{

	nextpc();
	p->as = a;
	p->from.type = D_EXTERN;
	p->from.sym = s;
	p->from.scale = (profileflg ? 0 : NOPROF);
	if(s->class == CSTATIC)
		p->from.type = D_STATIC;
	naddr(n, &p->to);
	if(a == ADATA || a == AGLOBL)
		pc--;
}

int
sconst(Node *n)
{
	long v;

	if(n->op == OCONST && !typefd[n->type->etype]) {
		v = n->vconst;
		if(v >= -32766L && v < 32766L)
			return 1;
	}
	return 0;
}

long
exreg(Type *t)
{

	USED(t);
	return 0;
}

schar	ewidth[NTYPE] =
{
	-1,		/*[TXXX]*/	
	SZ_CHAR,	/*[TCHAR]*/	
	SZ_CHAR,	/*[TUCHAR]*/
	SZ_SHORT,	/*[TSHORT]*/
	SZ_SHORT,	/*[TUSHORT]*/
	SZ_INT,		/*[TINT]*/
	SZ_INT,		/*[TUINT]*/
	SZ_LONG,	/*[TLONG]*/
	SZ_LONG,	/*[TULONG]*/
	SZ_VLONG,	/*[TVLONG]*/
	SZ_VLONG,	/*[TUVLONG]*/
	SZ_FLOAT,	/*[TFLOAT]*/
	SZ_DOUBLE,	/*[TDOUBLE]*/
	SZ_IND,		/*[TIND]*/
	0,		/*[TFUNC]*/
	-1,		/*[TARRAY]*/
	0,		/*[TVOID]*/
	-1,		/*[TSTRUCT]*/
	-1,		/*[TUNION]*/
	SZ_INT,		/*[TENUM]*/
};
long	ncast[NTYPE] =
{
	0,				/*[TXXX]*/
	BCHAR|BUCHAR,			/*[TCHAR]*/
	BCHAR|BUCHAR,			/*[TUCHAR]*/	
	BSHORT|BUSHORT,			/*[TSHORT]*/
	BSHORT|BUSHORT,			/*[TUSHORT]*/
	BINT|BUINT|BLONG|BULONG|BIND,	/*[TINT]*/		
	BINT|BUINT|BLONG|BULONG|BIND,	/*[TUINT]*/
	BINT|BUINT|BLONG|BULONG|BIND,	/*[TLONG]*/
	BINT|BUINT|BLONG|BULONG|BIND,	/*[TULONG]*/
	BVLONG|BUVLONG,			/*[TVLONG]*/
	BVLONG|BUVLONG,			/*[TUVLONG]*/
	BFLOAT,				/*[TFLOAT]*/
	BDOUBLE,			/*[TDOUBLE]*/
	BLONG|BULONG|BIND,		/*[TIND]*/
	0,				/*[TFUNC]*/
	0,				/*[TARRAY]*/
	0,				/*[TVOID]*/
	BSTRUCT,			/*[TSTRUCT]*/
	BUNION,				/*[TUNION]*/
	0,				/*[TENUM]*/
};