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libregexp/regcomp.c  view on Meta::CPAN

			inst1 = newinst(OR);
			inst1->u1.right = op1->first;
			inst1->u2.left = op2->first;
			pushand(inst1, inst2);
			break;
		case CAT:
			op2 = popand(0);
			op1 = popand(0);
			op1->last->u2.next = op2->first;
			pushand(op1->first, op2->last);
			break;
		case STAR:
			op2 = popand('*');
			inst1 = newinst(OR);
			op2->last->u2.next = inst1;
			inst1->u1.right = op2->first;
			pushand(inst1, inst1);
			break;
		case PLUS:
			op2 = popand('+');
			inst1 = newinst(OR);
			op2->last->u2.next = inst1;
			inst1->u1.right = op2->first;
			pushand(op2->first, inst1);
			break;
		case QUEST:
			op2 = popand('?');
			inst1 = newinst(OR);
			inst2 = newinst(NOP);
			inst1->u2.left = inst2;
			inst1->u1.right = op2->first;
			op2->last->u2.next = inst2;
			pushand(inst1, inst2);
			break;
		}
	}
}

static	Reprog*
optimize(Reprog *pp)
{
	Reinst *inst, *target;
	int size;
	Reprog *npp;
	Reclass *cl;
	int diff;

	/*
	 *  get rid of NOOP chains
	 */
	for(inst=pp->firstinst; inst->type!=END; inst++){
		target = inst->u2.next;
		while(target->type == NOP)
			target = target->u2.next;
		inst->u2.next = target;
	}

	/*
	 *  The original allocation is for an area larger than
	 *  necessary.  Reallocate to the actual space used
	 *  and then relocate the code.
	 */
	size = sizeof(Reprog) + (freep - pp->firstinst)*sizeof(Reinst);
	npp = realloc(pp, size);
	if(npp==0 || npp==pp)
		return pp;
	diff = (char *)npp - (char *)pp;
	freep = (Reinst *)((char *)freep + diff);
	for(inst=npp->firstinst; inst<freep; inst++){
		switch(inst->type){
		case OR:
		case STAR:
		case PLUS:
		case QUEST:
			*(char **)&inst->u1.right += diff;
			break;
		case CCLASS:
		case NCCLASS:
			*(char **)&inst->u1.right += diff;
			cl = inst->u1.cp;
			*(char **)&cl->end += diff;
			break;
		}
		*(char **)&inst->u2.left += diff;
	}
	*(char **)&npp->startinst += diff;
	return npp;
}

#ifdef	DEBUG
static	void
dumpstack(void){
	Node *stk;
	int *ip;

	print("operators\n");
	for(ip=atorstack; ip<atorp; ip++)
		print("0%o\n", *ip);
	print("operands\n");
	for(stk=andstack; stk<andp; stk++)
		print("0%o\t0%o\n", stk->first->type, stk->last->type);
}

static	void
dump(Reprog *pp)
{
	Reinst *l;
	Rune *p;

	l = pp->firstinst;
	do{
		print("%d:\t0%o\t%d\t%d", l-pp->firstinst, l->type,
			l->u2.left-pp->firstinst, l->u1.right-pp->firstinst);
		if(l->type == RUNE)
			print("\t%C\n", l->u1.r);
		else if(l->type == CCLASS || l->type == NCCLASS){
			print("\t[");
			if(l->type == NCCLASS)
				print("^");
			for(p = l->u1.cp->spans; p < l->u1.cp->end; p += 2)
				if(p[0] == p[1])