[unix-history] / usr / src / old / pcc / c2.vax / c20.c

#ifndef lint
static	char sccsid[] = "@(#)c20.c	4.9 (Berkeley) %G%";
#endif

/*
 *	 C object code improver
 */

#include "c2.h"
#include <stdio.h>
#include <ctype.h>
#include <sys/types.h>

char _sibuf[BUFSIZ], _sobuf[BUFSIZ];
caddr_t sbrk();
int ioflag;
int fflag;
long	isn	= 2000000;
struct optab *oplook();
struct optab *getline();
long lgensym[10] =
  {100000L,200000L,300000L,400000L,500000L,600000L,700000L,800000L,900000L,1000000L};

#define ALLOCSIZE	4096

struct node *
alloc(an)
{
	register int n;
	register struct node *p;

	n = an;
	n+=sizeof(char *)-1;
	n &= ~(sizeof(char *)-1);
	if (lasta+n >= lastr) {
		if ((int) sbrk(ALLOCSIZE) == -1) {
			fprintf(stderr, "Optimizer: out of space\n");
			exit(1);
		}
		lastr += ALLOCSIZE;
	}
	p = (struct node *) lasta;
	lasta += n;
	return(p);
}

main(argc, argv)
char **argv;
{
	register int niter, maxiter, isend;
	int nflag,infound;

	nflag = 0; infound=0; argc--; argv++;
	while (argc>0) {/* get flags */
		if (**argv=='+') debug++;
		else if (**argv=='-') {
			if ((*argv)[1]=='i') ioflag++;
			else if ((*argv)[1]=='f') fflag++;
			else nflag++;
		} else if (infound==0) {
			if (freopen(*argv, "r", stdin) ==NULL) {
				fprintf(stderr,"C2: can't find %s\n", *argv);
				exit(1);
			}
			++infound;
		} else if (freopen(*argv, "w", stdout) ==NULL) {
			fprintf(stderr,"C2: can't create %s\n", *argv);
			exit(1);
		}
		argc--; argv++;
	}
	setbuf(stdin, _sibuf);
	setbuf(stdout, _sobuf);
	lasta = lastr = (char *) sbrk(2);
	opsetup();
	lasta = firstr = lastr = (char *) alloc(0);
	maxiter = 0;
	do {
		isend = input();
		niter = 0;
		bmove();
		do {
			refcount();
			do {
				iterate();
				clearreg();
				niter++;
			} while (nchange);
			comjump();
			rmove();
		} while (nchange || jumpsw());
		addsob();
		output();
		if (niter > maxiter)
			maxiter = niter;
		lasta = firstr;
	} while (isend);
	if (nflag) {
		fprintf(stderr,"%d iterations\n", maxiter);
		fprintf(stderr,"%d jumps to jumps\n", nbrbr);
		fprintf(stderr,"%d inst. after jumps\n", iaftbr);
		fprintf(stderr,"%d jumps to .+1\n", njp1);
		fprintf(stderr,"%d redundant labels\n", nrlab);
		fprintf(stderr,"%d cross-jumps\n", nxjump);
		fprintf(stderr,"%d code motions\n", ncmot);
		fprintf(stderr,"%d branches reversed\n", nrevbr);
		fprintf(stderr,"%d redundant moves\n", redunm);
		fprintf(stderr,"%d simplified addresses\n", nsaddr);
		fprintf(stderr,"%d loops inverted\n", loopiv);
		fprintf(stderr,"%d redundant jumps\n", nredunj);
		fprintf(stderr,"%d common seqs before jmp's\n", ncomj);
		fprintf(stderr,"%d skips over jumps\n", nskip);
		fprintf(stderr,"%d sob's added\n", nsob);
		fprintf(stderr,"%d redundant tst's\n", nrtst);
		fprintf(stderr,"%d jump on bit\n", nbj);
		fprintf(stderr,"%d field operations\n", nfield);
		fprintf(stderr,"%dK core\n", ((unsigned)lastr+01777) >> 10);
	}
	putc('\n',stdout);
	fflush(stdout); exit(0);
}

input()
{
	register struct node *p, *lastp;
	struct optab *opp; register char *cp1;
	static struct optab F77JSW = {".long", T(JSW,1)};

	lastp = &first;
	for (;;) {
	  top:
		opp = getline();
		if (debug && opp==0) fprintf(stderr,"? %s\n",line);
		switch (opp->opcode&0377) {
	
		case LABEL:
			p = alloc(sizeof first);
			if (isdigit(line[0]) && (p->labno=locdef(line)) ||
			  (line[0] == 'L') && (p->labno=getnum(line+1))) {
				p->combop = LABEL;
				if (p->labno<100000L && isn<=p->labno) isn=1+p->labno;
				p->code = 0;
			} else {
				p->combop = DLABEL;
				p->labno = 0;
				p->code = copy(line);
			}
			break;
	
		case LGEN:
			if (*curlp!='L' && !locuse(curlp)) goto std;
			opp= &F77JSW;
		case JBR:
			if (opp->opcode==T(JBR,RET) || opp->opcode==T(JBR,RSB)) goto std;
		case CBR:
		case JMP:
		case JSW:
		case SOBGEQ: case SOBGTR: case AOBLEQ: case AOBLSS: case ACB:
			p = alloc(sizeof first);
			p->combop = opp->opcode; p->code=0; cp1=curlp;
			if ((!isdigit(*cp1) || 0==(p->labno=locuse(cp1))) &&
			  (*cp1!='L' || 0==(p->labno = getnum(cp1+1)))) {/* jbs, etc.? */
				while (*cp1++); while (*--cp1!=',' && cp1!=curlp);
				if (cp1==curlp ||
				  (!isdigit(*++cp1) || 0==(p->labno=locuse(cp1))) &&
				  (*cp1!='L' || 0==(p->labno=getnum(cp1+1))))
					p->labno = 0;
				else *--cp1=0;
				p->code = copy(curlp);
			}
			if (isn<=p->labno) isn=1+p->labno;
			break;

		case MOVA:
			p=alloc(sizeof first);
			p->combop=opp->opcode; p->code=0; cp1=curlp+1;
			if (cp1[-1]=='L' || isdigit(cp1[-1])) {
				while (*cp1++!=','); *--cp1=0;
				if (0!=(p->labno=locuse(curlp)) ||
					0!=(p->labno=getnum(curlp+1))) p->code=copy(cp1+1);
				else {*cp1=','; p->code=copy(curlp);}
			} else {p->code=copy(--cp1); p->labno=0;}
			break;

		case SET:
		case COMM:
		case LCOMM:
			printf("%s\n",line); goto top;

		case BSS:
		case DATA:
			for (;;) {
				printf("%s%c",line,(opp->opcode==LABEL ? ':' : '\n'));
				if (opp->opcode==TEXT) goto top;
				if (END==(opp=getline())->opcode) {/* dangling .data is bad for you */
					printf(".text\n");
					break;
				}
			}

		std:
		default:
			p = alloc(sizeof first);
			p->combop = opp->opcode;
			p->labno = 0;
			p->code = copy(curlp);
			break;

		}
		p->forw = 0;
		p->back = lastp;
		p->pop = opp;
		lastp->forw = p;
		lastp = p;
		p->ref = 0;
		if (p->op==CASE) {
			char *lp; int ncase;
			lp=curlp; while (*lp++); while (*--lp!='$'); ncase=getnum(lp+1);
			if (LABEL!=(getline())->opcode) {
				fprintf(stderr, "c2: garbled 'case' instruction\n");
				exit(-2);
			}
			do {
				if (WGEN!=(getline())->opcode) {
					fprintf(stderr, "c2: garbled 'case' instruction\n");
					exit(-3);
				}
				p = alloc(sizeof first); p->combop = JSW; p->code = 0;
				lp=curlp; while(*lp++!='-'); *--lp=0; p->labno=getnum(curlp+1);
				if (isn<=p->labno) isn=1+p->labno;
				p->forw = 0; p->back = lastp; lastp->forw = p; lastp = p;
				p->ref = 0; p->pop=0;
			} while (--ncase>=0);
		}
		if (opp->opcode==EROU)
			return(1);
		if (opp->opcode==END)
			return(0);
	}
}

struct optab *
getline()
{
	register char *lp;
	register c;
	static struct optab OPLABEL={"",LABEL};
	static struct optab OPEND={"",END};

	lp = line;
	while (EOF!=(c=getchar()) && isspace(c));
	while (EOF!=c) {
		if (c==':') {
			*lp++ = 0;
			return(&OPLABEL);
		}
		if (c=='\n') {
			*lp++ = 0;
			return(oplook());
		}
		*lp++ = c;
		c = getchar();
	}
	*lp++ = 0;
	return(&OPEND);
}

long
getnum(p)
register char *p;
{
	register c; int neg; register long n;

	n = 0; neg=0; if (*p=='-') {++neg; ++p;}
	while (isdigit(c = *p++)) {
		 c -= '0'; n *= 10; if (neg) n -= c; else n += c;
	}
	if (*--p != 0)
		return(0);
	return(n);
}

locuse(p)
register char *p;
{
	if (!isdigit(p[0]) || p[1] != 'f' && p[1] != 'b' || p[2]) return(0);
	return (lgensym[p[0] - '0'] - (p[1] == 'b'));
}

locdef(p)
register char *p;
{

	if (!isdigit(p[0]) || p[1]) return(0);
	return (lgensym[p[0] - '0']++);
}

output()
{
	register struct node *t;
	int casebas;

	t = &first;
	while (t = t->forw) switch (t->op) {

	case END:
		fflush(stdout);
		return;

	case LABEL:
		printf("L%d:", t->labno);
		continue;

	case DLABEL:
		printf("%s:", t->code);
		continue;

	case CASE:
		casebas=0;

	default: std:
		if (t->pop==0) {/* must find it */
			register struct optab *p;
			for (p=optab; p->opstring[0]; ++p)
				if (p->opcode==t->combop) {t->pop=p; break;}
		}
		printf("%s", t->pop->opstring);
		if (t->code) printf("\t%s", t->code);
		if (t->labno!=0) printf("%cL%d\n",
							(t->code ? ',' : '\t'),
							t->labno);
		else printf("\n");
		continue;

	case MOVA:
		if (t->labno==0) goto std;
		printf("mova%c\tL%d,%s\n","bwlq"[t->subop-BYTE],t->labno,t->code);
		continue;

	case JSW:
		if (t->subop!=0) {/* F77JSW */
			printf(".long\tL%d\n",t->labno); continue;
		}
		if (casebas==0) printf("L%d:\n",casebas=isn++);
		printf(".word	L%d-L%d\n", t->labno, casebas);
		continue;
	case MOV:
		if (!fflag) goto std;
		if (t->forw) if(t->forw->op == CBR) goto std;
		if (*t->code == '$') goto std;
		if (t->subop == FFLOAT)
			{
			printf("movl\t%s\n", t->code);
			continue;
			}
		if (t->subop == DFLOAT || t->subop == GFLOAT)
			{
			printf("movq\t%s\n", t->code);
			continue;
			}
		if (t->subop == HFLOAT)
			{
			printf("movo\t%s\n", t->code);
			continue;
			}
		goto std;

	}
}

char *
copy(ap)
char *ap;
{
	register char *p, *np;
	char *onp;
	register n;
	int na;

	na = nargs();
	p = ap;
	n = 0;
	if (*p==0)
		return(0);
	do
		n++;
	while (*p++);
	if (na>1) {
		p = (&ap)[1];
		while (*p++)
			n++;
	}
	onp = np = (char *) alloc(n);
	p = ap;
	while (*np++ = *p++);
	if (na>1) {
		p = (&ap)[1];
		np--;
		while (*np++ = *p++);
	}
	return(onp);
}

#define	OPHS	560
struct optab *ophash[OPHS];

opsetup()
{
	register struct optab *optp, **ophp;
	register int i,t;

	for(i=NREG+5;--i>=0;) regs[i]=(char *) alloc(C2_ASIZE);
	for (optp = optab; optp->opstring[0]; optp++) {
		t=7; i=0; while (--t>=0) i+= i+optp->opstring[t];
		ophp = &ophash[i % OPHS];
		while (*ophp++) {
/*			fprintf(stderr,"\ncollision: %d %s %s",
/*				ophp-1-ophash,optp->opstring,(*(ophp-1))->opstring);
*/
			if (ophp > &ophash[OPHS])
				ophp = ophash;
		}
		*--ophp = optp;
	}
}

struct optab *
oplook()
{
	register struct optab *optp,**ophp;
	register char *p,*p2;
	register int t;
	char tempop[20];
	static struct optab OPNULL={"",0};

	for (p=line, p2=tempop; *p && !isspace(*p); *p2++= *p++); *p2=0; p2=p;
	while (isspace(*p2)) ++p2; curlp=p2;
	t=0; while(--p>=line) t += t+*p; ophp = &ophash[t % OPHS];
	while (optp = *ophp) {
		if (equstr(tempop,optp->opstring)) return(optp);
		if ((++ophp) >= &ophash[OPHS]) ophp = ophash;
	}
	curlp = line;
	return(&OPNULL);
}

refcount()
{
	register struct node *p, *lp, *tp;
	struct node *labhash[LABHS];
	register struct node **hp;

	for (hp = labhash; hp < &labhash[LABHS];)
		*hp++ = 0;
	for (p = first.forw; p!=0; p = p->forw)
		if (p->op==LABEL) {
			labhash[p->labno % LABHS] = p;
			p->refc = 0;
		}
	for (p = first.forw; p!=0; p = p->forw) {
		if (p->combop==JBR || p->op==CBR || p->op==JSW || p->op==JMP
		  || p->op==SOBGEQ || p->op==SOBGTR || p->op==AOBLEQ || p->op==AOBLSS
		  || p->op==ACB || (p->op==MOVA && p->labno!=0)) {
			p->ref = 0;
			lp = labhash[p->labno % LABHS];
			if (lp==0 || p->labno!=lp->labno)
			for (lp = first.forw; lp!=0; lp = lp->forw) {
				if (lp->op==LABEL && p->labno==lp->labno)
					break;
			}
			if (lp) {
				tp = nonlab(lp)->back;
				if (tp!=lp) {
					p->labno = tp->labno;
					lp = tp;
				}
				p->ref = lp;
				lp->refc++;
			}
		}
	}
	for (p = first.forw; p!=0; p = p->forw)
		if (p->op==LABEL && p->refc==0
		 && (lp = nonlab(p))->op && lp->op!=JSW)
			decref(p);
}

iterate()
{
	register struct node *p, *rp, *p1;

	nchange = 0;
	for (p = first.forw; p!=0; p = p->forw) {
		if ((p->op==JBR||p->op==CBR||p->op==JSW) && p->ref) {
			rp = nonlab(p->ref);
			if (rp->op==JBR && rp->labno && p->labno!=rp->labno) {
				nbrbr++;
				p->labno = rp->labno;
				decref(p->ref);
				rp->ref->refc++;
				p->ref = rp->ref;
				nchange++;
			}
		}
#ifndef COPYCODE
		if (p->op==CBR && (p1 = p->forw)->combop==JBR) {/* combop: RET problems */
#else
		if (p->op==CBR && (p1 = p->forw)->combop==JBR &&
		    p->ref) {/* combop: RET problems */
#endif
			rp = p->ref;
			do
				rp = rp->back;
			while (rp->op==LABEL);
			if (rp==p1) {
				decref(p->ref);
				p->ref = p1->ref;
				p->labno = p1->labno;
#ifdef COPYCODE
				if (p->labno == 0)
					p->code = p1->code;
#endif
				p1->forw->back = p;
				p->forw = p1->forw;
				p->subop = revbr[p->subop];
				p->pop=0;
				nchange++;
				nskip++;
			}
		}
		if (p->op==JBR || p->op==JMP) {
			while (p->forw && p->forw->op!=LABEL && p->forw->op!=DLABEL
				&& p->forw->op!=EROU && p->forw->op!=END
				&& p->forw->op!=ALIGN
				&& p->forw->op!=0 && p->forw->op!=DATA) {
				nchange++;
				iaftbr++;
				if (p->forw->ref)
					decref(p->forw->ref);
				p->forw = p->forw->forw;
				p->forw->back = p;
			}
			rp = p->forw;
			while (rp && rp->op==LABEL) {
				if (p->ref == rp) {
					p->back->forw = p->forw;
					p->forw->back = p->back;
					p = p->back;
					decref(rp);
					nchange++;
					njp1++;
					break;
				}
				rp = rp->forw;
			}
			xjump(p);
			p = codemove(p);
		}
	}
}

xjump(p1)
register struct node *p1;
{
	register struct node *p2, *p3;

	if ((p2 = p1->ref)==0)
		return;
	for (;;) {
		while ((p1 = p1->back) && p1->op==LABEL);
		while ((p2 = p2->back) && p2->op==LABEL);
		if (!equop(p1, p2) || p1==p2)
			return;
		p3 = insertl(p2);
		p1->combop = JBR;
		p1->pop=0;
		p1->ref = p3;
		p1->labno = p3->labno;
		p1->code = 0;
		nxjump++;
		nchange++;
	}
}

struct node *
insertl(np)
register struct node *np;
{
	register struct node *lp;

	if (np->op == LABEL) {
		np->refc++;
		return(np);
	}
	if (np->back->op == LABEL) {
		np = np->back;
		np->refc++;
		return(np);
	}
	lp = alloc(sizeof first);
	lp->combop = LABEL;
	lp->labno = isn++;
	lp->ref = 0;
	lp->code = 0;
	lp->refc = 1;
	lp->back = np->back;
	lp->forw = np;
	np->back->forw = lp;
	np->back = lp;
	return(lp);
}

struct node *
codemove(ap)
struct node *ap;
{
	register struct node *p1, *p2, *p3;
	struct node *t, *tl;
	int n;

	p1 = ap;
/* last clause to avoid infinite loop on partial compiler droppings:
	L183:	jbr L179
	L191:	jbr L179
			casel r0,$0,$1
	L193:	.word L183-L193
			.word L191-L193
	L179:	ret
*/
	if (p1->op!=JBR || (p2 = p1->ref)==0 || p2==p1->forw)
		return(p1);
	while (p2->op == LABEL)
		if ((p2 = p2->back) == 0)
			return(p1);
	if (p2->op!=JBR && p2->op!=JMP)
		goto ivloop;
	p2 = p2->forw;
	p3 = p1->ref;
	while (p3) {
		if (p3->op==JBR || p3->op==JMP) {
			if (p1==p3)
				return(p1);
			ncmot++;
			nchange++;
			p1->back->forw = p2;
			p1->forw->back = p3;
			p2->back->forw = p3->forw;
			p3->forw->back = p2->back;
			p2->back = p1->back;
			p3->forw = p1->forw;
			decref(p1->ref);
			return(p2);
		} else
			p3 = p3->forw;
	}
	return(p1);
ivloop:
	if (p1->forw->op!=LABEL)
		return(p1);
	p3 = p2 = p2->forw;
	n = 16;
	do {
		if ((p3 = p3->forw) == 0 || p3==p1 || --n==0)
			return(p1);
	} while (p3->op!=CBR || p3->labno!=p1->forw->labno);
	do 
		if ((p1 = p1->back) == 0)
			return(ap);
	while (p1!=p3);
	p1 = ap;
	tl = insertl(p1);
	p3->subop = revbr[p3->subop];
	p3->pop=0;
	decref(p3->ref);
	p2->back->forw = p1;
	p3->forw->back = p1;
	p1->back->forw = p2;
	p1->forw->back = p3;
	t = p1->back;
	p1->back = p2->back;
	p2->back = t;
	t = p1->forw;
	p1->forw = p3->forw;
	p3->forw = t;
	p2 = insertl(p1->forw);
	p3->labno = p2->labno;
#ifdef COPYCODE
	if (p3->labno == 0)
		p3->code = p2->code;
#endif
	p3->ref = p2;
	decref(tl);
	if (tl->refc<=0)
		nrlab--;
	loopiv++;
	nchange++;
	return(p3);
}

comjump()
{
	register struct node *p1, *p2, *p3;

	for (p1 = first.forw; p1!=0; p1 = p1->forw)
		if (p1->op==JBR && ((p2 = p1->ref) && p2->refc > 1
				|| p1->subop==RET || p1->subop==RSB))
			for (p3 = p1->forw; p3!=0; p3 = p3->forw)
				if (p3->op==JBR && p3->ref == p2)
					backjmp(p1, p3);
}

backjmp(ap1, ap2)
struct node *ap1, *ap2;
{
	register struct node *p1, *p2, *p3;

	p1 = ap1;
	p2 = ap2;
	for(;;) {
		while ((p1 = p1->back) && p1->op==LABEL);
		p2 = p2->back;
		if (equop(p1, p2)) {
			p3 = insertl(p1);
			p2->back->forw = p2->forw;
			p2->forw->back = p2->back;
			p2 = p2->forw;
			decref(p2->ref);
			p2->combop = JBR; /* to handle RET */
			p2->pop=0;
			p2->labno = p3->labno;
#ifdef COPYCODE
			p2->code = 0;
#endif
			p2->ref = p3;
			nchange++;
			ncomj++;
		} else
			return;
	}
}
Commit	Line	Data
b767c045	1	#ifndef lint
41feb04a	2	static char sccsid[] = "@(#)c20.c 4.9 (Berkeley) %G%";
b767c045 SL	3	#endif
b767c045 SL	4
08b50d78 BJ	5	/*
	6	* C object code improver
	7	*/
	8
	9	#include "c2.h"
	10	#include <stdio.h>
	11	#include <ctype.h>
41feb04a	12	#include <sys/types.h>
08b50d78 BJ	13
08b50d78 BJ	14	char _sibuf[BUFSIZ], _sobuf[BUFSIZ];
41feb04a	15	caddr_t sbrk();
08b50d78	16	int ioflag;
11850887	17	int fflag;
d9657d8c	18	long isn = 2000000;
08b50d78 BJ	19	struct optab *oplook();
08b50d78 BJ	20	struct optab *getline();
d9657d8c BJ	21	long lgensym[10] =
d9657d8c BJ	22	{100000L,200000L,300000L,400000L,500000L,600000L,700000L,800000L,900000L,1000000L};
08b50d78	23
41feb04a RC	24	#define ALLOCSIZE 4096
41feb04a RC	25
08b50d78 BJ	26	struct node *
	27	alloc(an)
	28	{
	29	register int n;
41feb04a	30	register struct node *p;
08b50d78 BJ	31
08b50d78 BJ	32	n = an;
d9657d8c BJ	33	n+=sizeof(char *)-1;
d9657d8c BJ	34	n &= ~(sizeof(char *)-1);
08b50d78	35	if (lasta+n >= lastr) {
41feb04a	36	if ((int) sbrk(ALLOCSIZE) == -1) {
08b50d78 BJ	37	fprintf(stderr, "Optimizer: out of space\n");
	38	exit(1);
	39	}
41feb04a	40	lastr += ALLOCSIZE;
08b50d78	41	}
41feb04a	42	p = (struct node *) lasta;
08b50d78 BJ	43	lasta += n;
	44	return(p);
	45	}
	46
	47	main(argc, argv)
	48	char **argv;
	49	{
	50	register int niter, maxiter, isend;
	51	int nflag,infound;
	52
	53	nflag = 0; infound=0; argc--; argv++;
	54	while (argc>0) {/* get flags */
	55	if (**argv=='+') debug++;
	56	else if (**argv=='-') {
11850887 RC	57	if ((*argv)[1]=='i') ioflag++;
	58	else if ((*argv)[1]=='f') fflag++;
	59	else nflag++;
08b50d78 BJ	60	} else if (infound==0) {
	61	if (freopen(*argv, "r", stdin) ==NULL) {
	62	fprintf(stderr,"C2: can't find %s\n", *argv);
	63	exit(1);
	64	}
778e4e6d	65	++infound;
08b50d78 BJ	66	} else if (freopen(*argv, "w", stdout) ==NULL) {
	67	fprintf(stderr,"C2: can't create %s\n", *argv);
	68	exit(1);
	69	}
08b50d78 BJ	70	argc--; argv++;
08b50d78 BJ	71	}
778e4e6d RC	72	setbuf(stdin, _sibuf);
778e4e6d RC	73	setbuf(stdout, _sobuf);
41feb04a	74	lasta = lastr = (char *) sbrk(2);
08b50d78	75	opsetup();
41feb04a	76	lasta = firstr = lastr = (char *) alloc(0);
08b50d78 BJ	77	maxiter = 0;
	78	do {
	79	isend = input();
	80	niter = 0;
	81	bmove();
	82	do {
	83	refcount();
	84	do {
	85	iterate();
	86	clearreg();
	87	niter++;
	88	} while (nchange);
	89	comjump();
	90	rmove();
	91	} while (nchange \|\| jumpsw());
	92	addsob();
	93	output();
	94	if (niter > maxiter)
	95	maxiter = niter;
	96	lasta = firstr;
	97	} while (isend);
	98	if (nflag) {
	99	fprintf(stderr,"%d iterations\n", maxiter);
	100	fprintf(stderr,"%d jumps to jumps\n", nbrbr);
	101	fprintf(stderr,"%d inst. after jumps\n", iaftbr);
	102	fprintf(stderr,"%d jumps to .+1\n", njp1);
	103	fprintf(stderr,"%d redundant labels\n", nrlab);
	104	fprintf(stderr,"%d cross-jumps\n", nxjump);
	105	fprintf(stderr,"%d code motions\n", ncmot);
	106	fprintf(stderr,"%d branches reversed\n", nrevbr);
	107	fprintf(stderr,"%d redundant moves\n", redunm);
	108	fprintf(stderr,"%d simplified addresses\n", nsaddr);
	109	fprintf(stderr,"%d loops inverted\n", loopiv);
	110	fprintf(stderr,"%d redundant jumps\n", nredunj);
	111	fprintf(stderr,"%d common seqs before jmp's\n", ncomj);
	112	fprintf(stderr,"%d skips over jumps\n", nskip);
	113	fprintf(stderr,"%d sob's added\n", nsob);
	114	fprintf(stderr,"%d redundant tst's\n", nrtst);
	115	fprintf(stderr,"%d jump on bit\n", nbj);
	116	fprintf(stderr,"%d field operations\n", nfield);
	117	fprintf(stderr,"%dK core\n", ((unsigned)lastr+01777) >> 10);
	118	}
	119	putc('\n',stdout);
	120	fflush(stdout); exit(0);
	121	}
	122
	123	input()
	124	{
	125	register struct node p, lastp;
41feb04a	126	struct optab opp; register char cp1;
08b50d78 BJ	127	static struct optab F77JSW = {".long", T(JSW,1)};
	128
	129	lastp = &first;
	130	for (;;) {
	131	top:
41feb04a RC	132	opp = getline();
	133	if (debug && opp==0) fprintf(stderr,"? %s\n",line);
	134	switch (opp->opcode&0377) {
08b50d78 BJ	135
	136	case LABEL:
	137	p = alloc(sizeof first);
	138	if (isdigit(line[0]) && (p->labno=locdef(line)) \|\|
	139	(line[0] == 'L') && (p->labno=getnum(line+1))) {
	140	p->combop = LABEL;
d9657d8c	141	if (p->labno<100000L && isn<=p->labno) isn=1+p->labno;
08b50d78 BJ	142	p->code = 0;
	143	} else {
	144	p->combop = DLABEL;
	145	p->labno = 0;
	146	p->code = copy(line);
	147	}
	148	break;
	149
	150	case LGEN:
	151	if (*curlp!='L' && !locuse(curlp)) goto std;
41feb04a	152	opp= &F77JSW;
08b50d78	153	case JBR:
41feb04a	154	if (opp->opcode==T(JBR,RET) \|\| opp->opcode==T(JBR,RSB)) goto std;
08b50d78 BJ	155	case CBR:
	156	case JMP:
	157	case JSW:
	158	case SOBGEQ: case SOBGTR: case AOBLEQ: case AOBLSS: case ACB:
	159	p = alloc(sizeof first);
41feb04a	160	p->combop = opp->opcode; p->code=0; cp1=curlp;
08b50d78 BJ	161	if ((!isdigit(*cp1) \|\| 0==(p->labno=locuse(cp1))) &&
	162	(cp1!='L' \|\| 0==(p->labno = getnum(cp1+1)))) {/ jbs, etc.? */
	163	while (cp1++); while (--cp1!=',' && cp1!=curlp);
	164	if (cp1==curlp \|\|
	165	(!isdigit(*++cp1) \|\| 0==(p->labno=locuse(cp1))) &&
	166	(*cp1!='L' \|\| 0==(p->labno=getnum(cp1+1))))
	167	p->labno = 0;
	168	else *--cp1=0;
	169	p->code = copy(curlp);
	170	}
	171	if (isn<=p->labno) isn=1+p->labno;
	172	break;
	173
	174	case MOVA:
	175	p=alloc(sizeof first);
41feb04a	176	p->combop=opp->opcode; p->code=0; cp1=curlp+1;
08b50d78 BJ	177	if (cp1[-1]=='L' \|\| isdigit(cp1[-1])) {
	178	while (cp1++!=','); --cp1=0;
	179	if (0!=(p->labno=locuse(curlp)) \|\|
	180	0!=(p->labno=getnum(curlp+1))) p->code=copy(cp1+1);
	181	else {*cp1=','; p->code=copy(curlp);}
	182	} else {p->code=copy(--cp1); p->labno=0;}
	183	break;
	184
	185	case SET:
	186	case COMM:
	187	case LCOMM:
	188	printf("%s\n",line); goto top;
	189
	190	case BSS:
	191	case DATA:
	192	for (;;) {
41feb04a RC	193	printf("%s%c",line,(opp->opcode==LABEL ? ':' : '\n'));
	194	if (opp->opcode==TEXT) goto top;
	195	if (END==(opp=getline())->opcode) {/* dangling .data is bad for you */
08b50d78 BJ	196	printf(".text\n");
	197	break;
	198	}
	199	}
	200
	201	std:
	202	default:
	203	p = alloc(sizeof first);
41feb04a	204	p->combop = opp->opcode;
08b50d78 BJ	205	p->labno = 0;
	206	p->code = copy(curlp);
	207	break;
	208
	209	}
	210	p->forw = 0;
	211	p->back = lastp;
41feb04a	212	p->pop = opp;
08b50d78 BJ	213	lastp->forw = p;
	214	lastp = p;
	215	p->ref = 0;
	216	if (p->op==CASE) {
	217	char *lp; int ncase;
	218	lp=curlp; while (lp++); while (--lp!='$'); ncase=getnum(lp+1);
41feb04a RC	219	if (LABEL!=(getline())->opcode) {
	220	fprintf(stderr, "c2: garbled 'case' instruction\n");
	221	exit(-2);
	222	}
08b50d78	223	do {
41feb04a RC	224	if (WGEN!=(getline())->opcode) {
	225	fprintf(stderr, "c2: garbled 'case' instruction\n");
	226	exit(-3);
	227	}
08b50d78 BJ	228	p = alloc(sizeof first); p->combop = JSW; p->code = 0;
	229	lp=curlp; while(lp++!='-'); --lp=0; p->labno=getnum(curlp+1);
	230	if (isn<=p->labno) isn=1+p->labno;
	231	p->forw = 0; p->back = lastp; lastp->forw = p; lastp = p;
	232	p->ref = 0; p->pop=0;
	233	} while (--ncase>=0);
	234	}
41feb04a	235	if (opp->opcode==EROU)
08b50d78	236	return(1);
41feb04a	237	if (opp->opcode==END)
08b50d78 BJ	238	return(0);
	239	}
	240	}
	241
	242	struct optab *
	243	getline()
	244	{
	245	register char *lp;
	246	register c;
	247	static struct optab OPLABEL={"",LABEL};
	248	static struct optab OPEND={"",END};
	249
	250	lp = line;
	251	while (EOF!=(c=getchar()) && isspace(c));
	252	while (EOF!=c) {
	253	if (c==':') {
	254	*lp++ = 0;
	255	return(&OPLABEL);
	256	}
	257	if (c=='\n') {
	258	*lp++ = 0;
	259	return(oplook());
	260	}
	261	*lp++ = c;
	262	c = getchar();
	263	}
	264	*lp++ = 0;
	265	return(&OPEND);
	266	}
	267
	268	long
	269	getnum(p)
	270	register char *p;
	271	{
	272	register c; int neg; register long n;
	273
	274	n = 0; neg=0; if (*p=='-') {++neg; ++p;}
	275	while (isdigit(c = *p++)) {
	276	c -= '0'; n *= 10; if (neg) n -= c; else n += c;
	277	}
	278	if (*--p != 0)
	279	return(0);
	280	return(n);
	281	}
	282
	283	locuse(p)
	284	register char *p;
	285	{
08b50d78 BJ	286	if (!isdigit(p[0]) \|\| p[1] != 'f' && p[1] != 'b' \|\| p[2]) return(0);
	287	return (lgensym[p[0] - '0'] - (p[1] == 'b'));
	288	}
	289
	290	locdef(p)
	291	register char *p;
	292	{
	293
	294	if (!isdigit(p[0]) \|\| p[1]) return(0);
	295	return (lgensym[p[0] - '0']++);
	296	}
	297
	298	output()
	299	{
	300	register struct node *t;
	301	int casebas;
	302
	303	t = &first;
	304	while (t = t->forw) switch (t->op) {
	305
	306	case END:
	307	fflush(stdout);
	308	return;
	309
	310	case LABEL:
	311	printf("L%d:", t->labno);
	312	continue;
	313
	314	case DLABEL:
	315	printf("%s:", t->code);
	316	continue;
	317
	318	case CASE:
	319	casebas=0;
	320
	321	default: std:
	322	if (t->pop==0) {/* must find it */
	323	register struct optab *p;
	324	for (p=optab; p->opstring[0]; ++p)
	325	if (p->opcode==t->combop) {t->pop=p; break;}
	326	}
	327	printf("%s", t->pop->opstring);
	328	if (t->code) printf("\t%s", t->code);
	329	if (t->labno!=0) printf("%cL%d\n",
	330	(t->code ? ',' : '\t'),
	331	t->labno);
	332	else printf("\n");
	333	continue;
	334
	335	case MOVA:
	336	if (t->labno==0) goto std;
	337	printf("mova%c\tL%d,%s\n","bwlq"[t->subop-BYTE],t->labno,t->code);
	338	continue;
	339
	340	case JSW:
	341	if (t->subop!=0) {/* F77JSW */
	342	printf(".long\tL%d\n",t->labno); continue;
	343	}
	344	if (casebas==0) printf("L%d:\n",casebas=isn++);
	345	printf(".word L%d-L%d\n", t->labno, casebas);
	346	continue;
11850887 RC	347	case MOV:
	348	if (!fflag) goto std;
	349	if (t->forw) if(t->forw->op == CBR) goto std;
	350	if (*t->code == '$') goto std;
	351	if (t->subop == FFLOAT)
	352	{
	353	printf("movl\t%s\n", t->code);
	354	continue;
	355	}
	356	if (t->subop == DFLOAT \|\| t->subop == GFLOAT)
	357	{
	358	printf("movq\t%s\n", t->code);
	359	continue;
	360	}
	361	if (t->subop == HFLOAT)
	362	{
	363	printf("movo\t%s\n", t->code);
	364	continue;
	365	}
	366	goto std;
08b50d78 BJ	367
	368	}
	369	}
	370
	371	char *
	372	copy(ap)
	373	char *ap;
	374	{
	375	register char p, np;
	376	char *onp;
	377	register n;
	378	int na;
	379
	380	na = nargs();
	381	p = ap;
	382	n = 0;
	383	if (*p==0)
	384	return(0);
	385	do
	386	n++;
	387	while (*p++);
	388	if (na>1) {
	389	p = (&ap)[1];
	390	while (*p++)
	391	n++;
	392	}
41feb04a	393	onp = np = (char *) alloc(n);
08b50d78 BJ	394	p = ap;
	395	while (np++ = p++);
	396	if (na>1) {
	397	p = (&ap)[1];
	398	np--;
	399	while (np++ = p++);
	400	}
	401	return(onp);
	402	}
	403
	404	#define OPHS 560
	405	struct optab *ophash[OPHS];
	406
	407	opsetup()
	408	{
	409	register struct optab optp, *ophp;
	410	register int i,t;
	411
41feb04a	412	for(i=NREG+5;--i>=0;) regs[i]=(char *) alloc(C2_ASIZE);
08b50d78 BJ	413	for (optp = optab; optp->opstring[0]; optp++) {
	414	t=7; i=0; while (--t>=0) i+= i+optp->opstring[t];
	415	ophp = &ophash[i % OPHS];
	416	while (*ophp++) {
	417	/* fprintf(stderr,"\ncollision: %d %s %s",
	418	/* ophp-1-ophash,optp->opstring,(*(ophp-1))->opstring);
	419	*/
	420	if (ophp > &ophash[OPHS])
	421	ophp = ophash;
	422	}
	423	*--ophp = optp;
	424	}
	425	}
	426
	427	struct optab *
	428	oplook()
	429	{
	430	register struct optab optp,*ophp;
	431	register char p,p2;
	432	register int t;
3b60efae	433	char tempop[20];
08b50d78 BJ	434	static struct optab OPNULL={"",0};
	435
	436	for (p=line, p2=tempop; p && !isspace(p); p2++= p++); *p2=0; p2=p;
	437	while (isspace(*p2)) ++p2; curlp=p2;
	438	t=0; while(--p>=line) t += t+*p; ophp = &ophash[t % OPHS];
	439	while (optp = *ophp) {
	440	if (equstr(tempop,optp->opstring)) return(optp);
	441	if ((++ophp) >= &ophash[OPHS]) ophp = ophash;
	442	}
	443	curlp = line;
	444	return(&OPNULL);
	445	}
	446
	447	refcount()
	448	{
41feb04a	449	register struct node p, lp, *tp;
08b50d78 BJ	450	struct node *labhash[LABHS];
	451	register struct node **hp;
	452
	453	for (hp = labhash; hp < &labhash[LABHS];)
	454	*hp++ = 0;
	455	for (p = first.forw; p!=0; p = p->forw)
	456	if (p->op==LABEL) {
	457	labhash[p->labno % LABHS] = p;
	458	p->refc = 0;
	459	}
	460	for (p = first.forw; p!=0; p = p->forw) {
	461	if (p->combop==JBR \|\| p->op==CBR \|\| p->op==JSW \|\| p->op==JMP
	462	\|\| p->op==SOBGEQ \|\| p->op==SOBGTR \|\| p->op==AOBLEQ \|\| p->op==AOBLSS
	463	\|\| p->op==ACB \|\| (p->op==MOVA && p->labno!=0)) {
	464	p->ref = 0;
	465	lp = labhash[p->labno % LABHS];
	466	if (lp==0 \|\| p->labno!=lp->labno)
	467	for (lp = first.forw; lp!=0; lp = lp->forw) {
	468	if (lp->op==LABEL && p->labno==lp->labno)
	469	break;
	470	}
	471	if (lp) {
41feb04a RC	472	tp = nonlab(lp)->back;
	473	if (tp!=lp) {
	474	p->labno = tp->labno;
	475	lp = tp;
08b50d78 BJ	476	}
	477	p->ref = lp;
	478	lp->refc++;
	479	}
	480	}
	481	}
	482	for (p = first.forw; p!=0; p = p->forw)
	483	if (p->op==LABEL && p->refc==0
	484	&& (lp = nonlab(p))->op && lp->op!=JSW)
	485	decref(p);
	486	}
	487
	488	iterate()
	489	{
	490	register struct node p, rp, *p1;
	491
	492	nchange = 0;
	493	for (p = first.forw; p!=0; p = p->forw) {
	494	if ((p->op==JBR\|\|p->op==CBR\|\|p->op==JSW) && p->ref) {
	495	rp = nonlab(p->ref);
	496	if (rp->op==JBR && rp->labno && p->labno!=rp->labno) {
	497	nbrbr++;
	498	p->labno = rp->labno;
	499	decref(p->ref);
	500	rp->ref->refc++;
	501	p->ref = rp->ref;
	502	nchange++;
	503	}
	504	}
	505	#ifndef COPYCODE
	506	if (p->op==CBR && (p1 = p->forw)->combop==JBR) {/* combop: RET problems */
	507	#else
	508	if (p->op==CBR && (p1 = p->forw)->combop==JBR &&
	509	p->ref) {/* combop: RET problems */
	510	#endif
	511	rp = p->ref;
	512	do
	513	rp = rp->back;
	514	while (rp->op==LABEL);
	515	if (rp==p1) {
	516	decref(p->ref);
	517	p->ref = p1->ref;
	518	p->labno = p1->labno;
	519	#ifdef COPYCODE
	520	if (p->labno == 0)
	521	p->code = p1->code;
	522	#endif
	523	p1->forw->back = p;
	524	p->forw = p1->forw;
	525	p->subop = revbr[p->subop];
	526	p->pop=0;
	527	nchange++;
	528	nskip++;
	529	}
	530	}
	531	if (p->op==JBR \|\| p->op==JMP) {
	532	while (p->forw && p->forw->op!=LABEL && p->forw->op!=DLABEL
	533	&& p->forw->op!=EROU && p->forw->op!=END
	534	&& p->forw->op!=ALIGN
	535	&& p->forw->op!=0 && p->forw->op!=DATA) {
	536	nchange++;
	537	iaftbr++;
	538	if (p->forw->ref)
	539	decref(p->forw->ref);
540	p->forw = p->forw->forw;
541	p->forw->back = p;
542	}
543	rp = p->forw;
544	while (rp && rp->op==LABEL) {
545	if (p->ref == rp) {
546	p->back->forw = p->forw;
547	p->forw->back = p->back;
548	p = p->back;
549	decref(rp);
550	nchange++;
551	njp1++;
552	break;
553	}
554	rp = rp->forw;
555	}
556	xjump(p);
557	p = codemove(p);
558	}
559	}
560	}
561
562	xjump(p1)
563	register struct node *p1;
564	{
565	register struct node p2, p3;
08b50d78	566
08b50d78	567	if ((p2 = p1->ref)==0)
41feb04a	568	return;
08b50d78 BJ	569	for (;;) {
	570	while ((p1 = p1->back) && p1->op==LABEL);
	571	while ((p2 = p2->back) && p2->op==LABEL);
	572	if (!equop(p1, p2) \|\| p1==p2)
41feb04a	573	return;
08b50d78 BJ	574	p3 = insertl(p2);
	575	p1->combop = JBR;
	576	p1->pop=0;
	577	p1->ref = p3;
	578	p1->labno = p3->labno;
	579	p1->code = 0;
08b50d78 BJ	580	nxjump++;
	581	nchange++;
	582	}
	583	}
	584
	585	struct node *
41feb04a RC	586	insertl(np)
41feb04a RC	587	register struct node *np;
08b50d78 BJ	588	{
	589	register struct node *lp;
	590
41feb04a RC	591	if (np->op == LABEL) {
	592	np->refc++;
	593	return(np);
08b50d78	594	}
41feb04a RC	595	if (np->back->op == LABEL) {
	596	np = np->back;
	597	np->refc++;
	598	return(np);
08b50d78 BJ	599	}
	600	lp = alloc(sizeof first);
	601	lp->combop = LABEL;
	602	lp->labno = isn++;
	603	lp->ref = 0;
	604	lp->code = 0;
	605	lp->refc = 1;
41feb04a RC	606	lp->back = np->back;
	607	lp->forw = np;
	608	np->back->forw = lp;
	609	np->back = lp;
08b50d78 BJ	610	return(lp);
	611	}
	612
	613	struct node *
	614	codemove(ap)
	615	struct node *ap;
	616	{
	617	register struct node p1, p2, *p3;
	618	struct node t, tl;
	619	int n;
	620
	621	p1 = ap;
	622	/* last clause to avoid infinite loop on partial compiler droppings:
	623	L183: jbr L179
	624	L191: jbr L179
	625	casel r0,$0,$1
	626	L193: .word L183-L193
	627	.word L191-L193
	628	L179: ret
	629	*/
	630	if (p1->op!=JBR \|\| (p2 = p1->ref)==0 \|\| p2==p1->forw)
	631	return(p1);
	632	while (p2->op == LABEL)
	633	if ((p2 = p2->back) == 0)
	634	return(p1);
	635	if (p2->op!=JBR && p2->op!=JMP)
	636	goto ivloop;
	637	p2 = p2->forw;
	638	p3 = p1->ref;
	639	while (p3) {
	640	if (p3->op==JBR \|\| p3->op==JMP) {
	641	if (p1==p3)
	642	return(p1);
	643	ncmot++;
	644	nchange++;
	645	p1->back->forw = p2;
	646	p1->forw->back = p3;
	647	p2->back->forw = p3->forw;
	648	p3->forw->back = p2->back;
	649	p2->back = p1->back;
	650	p3->forw = p1->forw;
	651	decref(p1->ref);
	652	return(p2);
	653	} else
	654	p3 = p3->forw;
	655	}
	656	return(p1);
	657	ivloop:
	658	if (p1->forw->op!=LABEL)
	659	return(p1);
	660	p3 = p2 = p2->forw;
	661	n = 16;
	662	do {
	663	if ((p3 = p3->forw) == 0 \|\| p3==p1 \|\| --n==0)
	664	return(p1);
	665	} while (p3->op!=CBR \|\| p3->labno!=p1->forw->labno);
	666	do
	667	if ((p1 = p1->back) == 0)
	668	return(ap);
	669	while (p1!=p3);
	670	p1 = ap;
	671	tl = insertl(p1);
	672	p3->subop = revbr[p3->subop];
	673	p3->pop=0;
674	decref(p3->ref);
675	p2->back->forw = p1;
676	p3->forw->back = p1;
677	p1->back->forw = p2;
678	p1->forw->back = p3;
679	t = p1->back;
680	p1->back = p2->back;
681	p2->back = t;
682	t = p1->forw;
683	p1->forw = p3->forw;
684	p3->forw = t;
685	p2 = insertl(p1->forw);
686	p3->labno = p2->labno;
687	#ifdef COPYCODE
688	if (p3->labno == 0)
689	p3->code = p2->code;
690	#endif
691	p3->ref = p2;
692	decref(tl);
693	if (tl->refc<=0)
694	nrlab--;
695	loopiv++;
696	nchange++;
697	return(p3);
698	}
699
700	comjump()
701	{
702	register struct node p1, p2, *p3;
703
704	for (p1 = first.forw; p1!=0; p1 = p1->forw)
705	if (p1->op==JBR && ((p2 = p1->ref) && p2->refc > 1
706	\|\| p1->subop==RET \|\| p1->subop==RSB))
707	for (p3 = p1->forw; p3!=0; p3 = p3->forw)
708	if (p3->op==JBR && p3->ref == p2)
709	backjmp(p1, p3);
710	}
711
712	backjmp(ap1, ap2)
713	struct node ap1, ap2;
714	{
715	register struct node p1, p2, *p3;
716
717	p1 = ap1;
718	p2 = ap2;
719	for(;;) {
720	while ((p1 = p1->back) && p1->op==LABEL);
721	p2 = p2->back;
722	if (equop(p1, p2)) {
723	p3 = insertl(p1);
724	p2->back->forw = p2->forw;
725	p2->forw->back = p2->back;
726	p2 = p2->forw;
727	decref(p2->ref);
728	p2->combop = JBR; /* to handle RET */
729	p2->pop=0;
730	p2->labno = p3->labno;
731	#ifdef COPYCODE
732	p2->code = 0;
733	#endif
734	p2->ref = p3;
735	nchange++;
736	ncomj++;
737	} else
738	return;
739	}
740	}