projects / unix-history / blame
? search:
summary | tags | clone url | shortlog | log | commit | commitdiff | tree
blob | blame (incremental) | history | HEAD
Added support for more than one board on a system
[unix-history] / usr / src / old / pcc / c2.vax / c21.c
CommitLineData
49c27f9c 1static char sccsid[] = "@(#)c21.c 4.10 %G%";
35307d30 2/* char C21[] = {"@(#)c21.c 1.83 80/10/16 21:18:22 JFR"}; /* sccs ident */
f00d91fc
BJ		 3
4/*
5 * C object code improver-- second part
6 */
7
8#include "c2.h"
9#include <stdio.h>
10#include <ctype.h>
11
12#define NUSE 6
13int ioflag;
14int biti[NUSE] = {1,2,4,8,16,32};
0594fe30 15int bitsize[] = { /* index by type codes */
a24e0abe
RH		 16 0, /* 0 not allocated */
17 8, /* 1 BYTE */
18 16, /* 2 WORD */
19 32, /* 3 LONG */
20 32, /* 4 FFLOAT /
21 64, /* 5 DFLOAT */
22 64, /* 6 QUAD */
23 0, /* 7 OP2 */
24 0, /* 8 OP3 */
25 0, /* 9 OPB */
26 0, /* 10 OPX */
27 64, /* 11 GFLOAT */
28 128, /* 12 HFLOAT */
29 128 /* 13 OCTA */
0594fe30 30};
f00d91fc
BJ		 31int pos,siz; long f; /* for bit field communication */
32struct node *uses[NUSE]; /* for backwards flow analysis */
33char *lastrand; /* last operand of instruction */
34struct node *bflow();
35struct node *bicopt();
36char *findcon();
37
38redun3(p,split) register struct node *p; int split; {
39/* check for 3 addr instr which should be 2 addr */
40 if (OP3==((p->subop>>4)&0xF)) {
41 if (split) splitrand(p);
42 if (equstr(regs[RT1],regs[RT3])
43 && (p->op==ADD || p->op==MUL || p->op==BIS || p->op==XOR)) {
44 register char *t=regs[RT1]; regs[RT1]=regs[RT2]; regs[RT2]=t;
45 }
46 if (equstr(regs[RT2],regs[RT3])) {
47 p->subop=(p->subop&0xF)|(OP2<<4); p->pop=0;
48 lastrand=regs[RT2]; *regs[RT3]=0; return(1);
49 }
50 } return(0);
51}
52
53bmove() {
54 register struct node *p, *lastp; register char *cp1,*cp2; register int r;
55 refcount();
56 for (p=lastp= &first; 0!=(p=p->forw); lastp=p);
57 clearreg(); clearuse();
58 for (p=lastp; p!= &first; p=p->back) {
59 if (debug) {
60 printf("Uses:\n");
61 for (r=NUSE;--r>=0;) if (uses[r])
62 printf("%d: %s\n",r,uses[r]->code? uses[r]->code:"");
63 printf("-\n");
64 }
65 r=(p->subop>>4)&0xF;
66 if (OP2==r && (cp1=p->code, *cp1++)=='$' && *cp1++=='0' && *cp1++==',' &&
67 !source(cp1)) {/* a no-op unless MUL or DIV */
68 if (p->op==MUL) {p->op=MOV; p->subop&=0xF; p->pop=0;}
69 else if (p->op==DIV) fprintf(stderr,"c2: zero divide\n");
70 else {delnode(p); redunm++; continue;}
71 }
72 if (OP3==r && 0!=redun3(p,1)) {newcode(p); redunm++;}
73 switch (p->op) {
74 case LABEL: case DLABEL:
75 for (r=NUSE; --r>=0;)
76 if (uses[r]) p->ref=(struct node *) (((int)p->ref)|biti[r]);
77 break;
78 case CALLS:
79 clearuse(); goto std;
80 case 0:
81 clearuse(); break;
82 case SUB:
83 if ((p->subop&0xF)!=LONG) goto std; cp1=p->code;
84 if (*cp1++!='$') goto std; splitrand(p);
85 if (equstr(regs[RT2],"fp") && !indexa(regs[RT1])) {/* address comp. */
3b60efae 86 char buf[C2_ASIZE]; cp2=buf; *cp2++='-';
f00d91fc
BJ		 87 cp1=regs[RT1]+1; while (*cp2++= *cp1++); --cp2;
88 cp1="(fp),"; while (*cp2++= *cp1++); --cp2;
89 cp1=regs[RT3]; while (*cp2++= *cp1++);
90 p->code=copy(buf); p->combop=T(MOVA,LONG); p->pop=0;
91 } else if (*cp1++=='-' && 0<=(r=getnum(cp1))) {
92 p->op=ADD; p->pop=0; *--cp1='$'; p->code=cp1;
93 } goto std;
94 case ADD:
95 if ((p->subop&0xF)!=LONG) goto std; cp1=p->code;
96 if (*cp1++!='$') goto std; splitrand(p);
97 if (isstatic(cp1) && (r=isreg(regs[RT2]))>=0 && r<NUSE && uses[r]==p->forw)
98 {
99 /* address comp:
100 ** addl2 $_foo,r0 \ movab _foo[r0],bar
101 ** movl r0,bar /
102 */
103 register struct node *pnext = p->forw;
3b60efae 104 char buf[C2_ASIZE];
f00d91fc
BJ		 105
106 if (pnext->op == MOV && pnext->subop == LONG)
107 {
108 cp1 = &regs[RT1][1]; cp2 = &buf[0];
109 while (*cp2++ = *cp1++) ; cp2--;
110 splitrand(pnext);
111 if (r == isreg(regs[RT1]))
112 {
113 delnode(p); p = pnext;
114 p->op = MOVA; p->subop = BYTE;
115 p->pop = 0;
116 cp1 = regs[RT1]; *cp2++ = '[';
117 while (*cp2++ = *cp1++) ; cp2--;
118 *cp2++ = ']'; *cp2++ = ',';
119 cp1 = regs[RT2];
120 while (*cp2++ = *cp1++) ;
121 p->code = copy(buf);
122 }
123 }
124 }
125 else
126 if (equstr(regs[RT2],"fp") && !indexa(regs[RT1])) {/* address comp. */
127 cp2=cp1-1; cp1=regs[RT1]+1; while (*cp2++= *cp1++); --cp2;
128 cp1="(fp)"; while (*cp2++= *cp1++); *--cp2=',';
129 p->combop=T(MOVA,LONG); p->pop=0;
130 } else if (*cp1++=='-' && 0<=(r=getnum(cp1))) {
131 p->op=SUB; p->pop=0; *--cp1='$'; p->code=cp1;
132 }
133 /* fall thru ... */
134 case CASE:
135 default: std:
136 p=bflow(p); break;
137 case MUL:
138 {
139 /*
140 ** Change multiplication by constant powers of 2 to
141 ** shifts.
142 */
143 splitrand(p);
144 if (regs[RT1][0] != '$' || regs[RT1][1] == '-') goto std;
145 if ((r = ispow2(getnum(&regs[RT1][1]))) < 0) goto std;
146 switch (r)
147 {
148 case 0: /* mull3 $1,x,y */
149 if (p->subop == U(LONG,OP3))
150 {
151 if (equstr(regs[RT2], regs[RT3]))
152 {
153 delnode(p); p = p->forw;
154 }
155 else
156 {
157 p->op = MOV; p->subop = LONG;
158 p->pop = 0; newcode(p); nchange++;
159 }
160 }
161 else
162 if (p->subop == U(LONG,OP2))
163 {
164 delnode(p); p = p->forw;
165 }
166 goto std;
167
168 case 1: /* mull2 $2,x */
169 if (p->subop == U(LONG, OP2) && !source(regs[RT2]))
170 {
171 strcpy(regs[RT1], regs[RT2]);
172 p->op = ADD; p->pop = 0; newcode(p); nchange++;
173 }
174 goto std;
175 }
176 if(p->subop==U(LONG,OP3)||(p->subop==U(LONG,OP2)&&!source(regs[RT2])))
177 {
178 if (p->subop == U(LONG,OP2))
179 strcpy(regs[RT3], regs[RT2]);
180 sprintf(regs[RT1], "$%d", r);
181 p->op = ASH; p->subop = LONG;
182 p->pop = 0; newcode(p); nchange++;
183 }
184 goto std;
185 }
186 case ASH:
187 {
188 /* address comp:
189 ** ashl $1,bar,r0 \ movl bar,r0
190 ** movab _foo[r0] / movaw _foo[r0]
191 **
192 ** ashl $2,r0,r0 \ moval _foo[r0]
193 ** movab _foo[r0] /
194 */
195 register struct node *pf;
196 register int shfrom, shto;
197 long shcnt;
198 char *regfrom;
199
200 splitrand(p);
201 if (regs[RT1][0] != '$') goto std;
202 if ((shcnt = getnum(&regs[RT1][1])) < 1 || shcnt > 3) goto std;
203 if ((shfrom = isreg(regs[RT2])) >= 0)
204 regfrom = copy(regs[RT2],"]");
205 if ((shto = isreg(regs[RT3])) >= 0 && shto<NUSE)
206 {
207 int regnum;
208
209 if (uses[shto] != (pf = p->forw)) goto ashadd;
210 if (pf->op != MOVA && pf->op != PUSHA) goto ashadd;
211 if (pf->subop != BYTE) goto ashadd;
212 splitrand(pf);
213 if (!indexa(regs[RT1])) goto std;
214 cp2 = regs[RT1];
215 if(!isstatic(cp2)) goto std;
216 while (*cp2++ != '[') ;
217 if (*cp2++ != 'r' || !isdigit(*cp2)) goto std;
218 regnum = *cp2++ - '0';
219 if (isdigit(*cp2))
220 {
221 if (cp2[1] != ']') goto std;
222 regnum *= 10; regnum += *cp2 - '0';
223 }
224 if (regnum != shto) goto std;
225 if (shfrom >= 0) /* ashl $N,r*,r0 */
226 {
227 delnode(p);
228 if (shfrom != shto)
229 {
230 uses[shto] = NULL; splitrand(pf);
231 cp2=regs[RT1]; while (*cp2++!='[');
232 cp1=regfrom; while (*cp2++= *cp1++);
233 newcode(pf);
234 }
235 }
236 else
237 {
238 p->op = MOV; splitrand(p);
239 strcpy(regs[RT1], regs[RT2]);
240 strcpy(regs[RT2], regs[RT3]);
241 regs[RT3][0] = '\0';
242 p->pop = 0; newcode(p);
243 }
244 switch (shcnt)
245 {
246 case 1: pf->subop = WORD; break;
247 case 2: pf->subop = LONG; break;
248 case 3: pf->subop = QUAD; break;
249 }
250 redunm++; nsaddr++; nchange++;
251 }
252 goto std;
253ashadd:
254 /* at this point, RT2 and RT3 are guaranteed to be simple regs*/
255 if (shcnt == 1 && equstr(regs[RT2], regs[RT3]))
256 {
257 /*
258 ** quickie:
259 ** ashl $1,A,A > addl2 A,A
260 */
261 p->op = ADD; p->subop = U(LONG,OP2); p->pop = 0;
262 strcpy(regs[RT1], regs[RT2]); regs[RT3][0] = '\0';
263 newcode(p); nchange++;
264 }
265 goto std;
266 }
267
268 case EXTV:
269 case EXTZV:
270 {
271 /* bit tests:
272 ** extv A,$1,B,rC \
273 ** tstl rC > jbc A,B,D
274 ** jeql D /
275 **
276 ** also byte- and word-size fields:
277 ** extv $n*8,$8,A,B > cvtbl n+A,B
49c27f9c 278 ** extv $n*16,$16,A,B > cvtwl 2n+A,B
f00d91fc 279 ** extzv $n*8,$8,A,B > movzbl n+A,B
49c27f9c 280 ** extzv $n*16,$16,A,B > movzwl 2n+A,B
f00d91fc
BJ		 281 */
282 register struct node *pf; /* forward node */
283 register struct node *pn; /* next node (after pf) */
284 int flen; /* field length */
285
286 splitrand(p);
287 if (regs[RT2][0] != '$') goto std;
288 if ((flen = getnum(&regs[RT2][1])) < 0) goto std;
289 if (flen == 1)
290 {
291 register int extreg; /* reg extracted to */
292
293 extreg = isreg(regs[RT4]);
294 if (extreg < 0 || extreg >= NUSE) goto std;
295 if ((pf = p->forw)->op != TST) goto std;
296 if (uses[extreg] && uses[extreg] != pf) goto std;
297 splitrand(pf);
298 if (extreg != isreg(regs[RT1])) goto std;
299 if ((pn = pf->forw)->op != CBR) goto std;
300 if (pn->subop != JEQ && pn->subop != JNE) goto std;
301 delnode(p); delnode(pf);
302 pn->subop = (pn->subop == JEQ) ? JBC : JBS;
303 for(cp2=p->code; *cp2++!=',';);
304 for(cp1=cp2; *cp1++!=',';);
305 while (*cp1!=',') *cp2++= *cp1++; *cp2='\0';
306 pn->code = p->code; pn->pop = NULL;
307 uses[extreg] = NULL;
308 }
309 else
310 if (flen == 8 || flen == 16)
311 {
312 register int boff; /* bit offset */
313 register int coff; /* chunk (byte or word) offset*/
314
315 if (regs[RT1][0] != '$') goto std;
316 if ((boff = getnum(&regs[RT1][1])) < 0) goto std;
317 coff = boff / flen;
318 if (coff && (isreg(regs[RT3]) >= 0)) goto std;
319 if (boff < 0 || (boff % flen) != 0) goto std;
320 p->op = (p->op == EXTV) ? CVT : MOVZ;
321 p->subop = U((flen == 8 ? BYTE : WORD), LONG);
322 if (coff == 0)
323 strcpy(regs[RT1], regs[RT3]);
324 else
49c27f9c
RC		 325 sprintf(regs[RT1], "%d%s%s",
326 (flen == 8 ? coff : 2*coff),
327 (regs[RT3][0] == '(' ? "" : "+"),
f00d91fc
BJ		 328 regs[RT3]);
329 strcpy(regs[RT2], regs[RT4]);
330 regs[RT3][0] = '\0'; regs[RT4][0] = '\0';
331 p->pop = 0; newcode(p);
332 }
333 nchange++;
334 goto std;
335 }
336
337 case CMP:
338 {
339 /* comparison to -63 to -1:
340 ** cmpl r0,$-1 > incl r0
341 ** jeql ...
342 **
343 ** cmpl r0,$-63 > addl2 $63,r0
344 ** jeql ...
345 */
346 register int num;
347 register int reg;
348 register struct node *regp = p->back;
349
350 if (p->forw->op != CBR) goto std;
351 if (p->forw->subop != JEQ && p->forw->subop != JNE) goto std;
352 splitrand(p);
353 if (strncmp(regs[RT2], "$-", 2) != 0) goto std;
354 reg = r = isreg(regs[RT1]);
355 if (r < 0) goto std;
356 if (r < NUSE && uses[r] != 0) goto std;
357 if (r >= NUSE && regp->op == MOV && p->subop == regp->subop)
358 {
359 if (*regp->code != 'r') goto std;
360 reg = regp->code[1] - '0';
361 if (isdigit(regp->code[2]) || reg >= NUSE || uses[reg])
362 goto std;
363 }
364 if (r >= NUSE) goto std;
365 if (reg != r)
366 sprintf(regs[RT1], "r%d", reg);
367 if ((num = getnum(&regs[RT2][2])) <= 0 || num > 63) goto std;
368 if (num == 1)
369 {
370 p->op = INC; regs[RT2][0] = '\0';
371 }
372 else
373 {
374 register char *t;
375
376 t=regs[RT1];regs[RT1]=regs[RT2];regs[RT2]=t;
377 p->op = ADD; p->subop = U(p->subop, OP2);
378 for (t = &regs[RT1][2]; t[-1] = *t; t++) ;
379 }
380 p->pop = 0; newcode(p);
381 nchange++;
382 goto std;
383 }
384
385 case JSB:
386 if (equstr(p->code,"mcount")) {uses[0]=p; regs[0][0]= -1;}
387 goto std;
388 case JBR: case JMP:
389 clearuse();
390 if (p->subop==RET || p->subop==RSB) {uses[0]=p; regs[0][0]= -1; break;}
391 if (p->ref==0) goto std; /* jmp (r0) */
392 /* fall through */
393 case CBR:
394 if (p->ref->ref!=0) for (r=NUSE;--r>=0;)
395 if (biti[r] & (int)p->ref->ref) {uses[r]=p; regs[r][0]= -1;}
396 case EROU: case JSW:
397 case TEXT: case DATA: case BSS: case ALIGN: case WGEN: case END: ;
398 }
399 }
400 for (p= &first; p!=0; p=p->forw)
401 if (p->op==LABEL || p->op==DLABEL) p->ref=0; /* erase our tracks */
402}
403
404rmove()
405{
406 register struct node *p, *lastp;
407 register int r;
408 int r1;
409
410 clearreg();
411 for (p=first.forw; p!=0; p = p->forw) {
412 lastp=p;
413 if (debug) {
414 printf("Regs:\n");
415 for (r=0; r<NREG; r++)
416 if (regs[r][0]) {
417 r1=regs[r][0];
418 printf("%d: %d%d %s\n", r, r1&0xF, r1>>4, regs[r]+1);
419 }
420 printf("-\n");
421 }
422 switch (p->op) {
423
424 case CVT:
425 splitrand(p); goto mov;
426
427 case MOV:
428 splitrand(p);
429 if ((r = findrand(regs[RT1],p->subop)) >= 0) {
430 if (r == isreg(regs[RT2]) && p->forw->op!=CBR) {
431 delnode(p); redunm++; break;
432 }
433 }
434mov:
435 repladdr(p);
436 r = isreg(regs[RT1]);
437 r1 = isreg(regs[RT2]);
438 dest(regs[RT2],p->subop);
d1580951
BJ		 439 if (r>=0) {
440 if (r1>=0) savereg(r1, regs[r]+1, p->subop);
441 else if (p->op!=CVT) savereg(r, regs[RT2], p->subop);
442 } else if (r1>=0) savereg(r1, regs[RT1], p->subop);
443 else if (p->op!=CVT) setcon(regs[RT1], regs[RT2], p->subop);
f00d91fc
BJ		 444 break;
445
446/* .rx,.wx */
447 case MFPR:
448 case COM:
449 case NEG:
450/* .rx,.wx or .rx,.rx,.wx */
451 case ADD:
452 case SUB:
453 case BIC:
454 case BIS:
455 case XOR:
456 case MUL:
457 case DIV:
458 case ASH:
459 case MOVZ:
460/* .rx,.rx,.rx,.wx */
461 case EXTV:
462 case EXTZV:
463 case INSV:
464 splitrand(p);
465 repladdr(p);
466 dest(lastrand,p->subop);
467 if (p->op==INSV) ccloc[0]=0;
468 break;
469
470/* .mx or .wx */
471 case CLR:
472 case INC:
473 case DEC:
474 splitrand(p);
475 dest(lastrand,p->subop);
476 if (p->op==CLR)
477 if ((r = isreg(regs[RT1])) >= 0)
478 savereg(r, "$0", p->subop);
479 else
480 setcon("$0", regs[RT1], p->subop);
481 break;
482
483/* .rx */
484 case TST:
485 case PUSH:
486 splitrand(p);
487 lastrand=regs[RT1+1]; /* fool repladdr into doing 1 operand */
488 repladdr(p);
489 if (p->op==TST && equstr(lastrand=regs[RT1], ccloc+1)
490 && ((0xf&(ccloc[0]>>4))==p->subop || equtype(ccloc[0],p->subop))
491 &&!source(lastrand)) {
492 delnode(p); p = p->back; nrtst++; nchange++;
493 }
494 setcc(lastrand,p->subop);
495 break;
496
497/* .rx,.rx,.rx */
498 case PROBER:
499 case PROBEW:
500 case CASE:
501 case MOVC3:
502/* .rx,.rx */
503 case MTPR:
504 case CALLS:
505 case CMP:
506 case BIT:
507 splitrand(p);
508 /* fool repladdr into doing right number of operands */
9ad46604 509 if (p->op==CASE || p->op==PROBER || p->op==PROBEW) lastrand=regs[RT4];
c2a86b7c 510/* else if (p->op==CMPV || p->op==CMPZV) lastrand=regs[RT4+1]; */
9ad46604 511 else if (p->op==MOVC3) lastrand=regs[RT1];
f00d91fc
BJ		 512 else lastrand=regs[RT3];
513 repladdr(p);
514 if (p->op==CALLS || p->op==MOVC3) clearreg();
515 if (p->op==BIT) bitopt(p);
516 ccloc[0]=0; break;
517
518 case CBR:
519 if (p->subop>=JBC) {
520 splitrand(p);
521 if (p->subop<JBCC) lastrand=regs[RT3]; /* 2 operands can be optimized */
522 else lastrand=regs[RT2]; /* .mb destinations lose */
523 repladdr(p);
524 }
525 ccloc[0] = 0;
526 break;
527
528 case JBR:
529 redunbr(p);
530
531/* .wx,.bb */
532 case SOB:
533
534 default:
535 clearreg();
536 }
537 }
538}
539
540char *
541byondrd(p) register struct node *p; {
542/* return pointer to register which is "beyond last read/modify operand" */
543 if (OP2==(p->subop>>4)) return(regs[RT3]);
544 switch (p->op) {
545 case MFPR:
546 case JSB:
547 case PUSHA:
548 case TST: case INC: case DEC: case PUSH: return(regs[RT2]);
549 case MTPR:
550 case BIT: case CMP: case CALLS: return(regs[RT3]);
551 case PROBER: case PROBEW:
552 case CASE: case MOVC3: return(regs[RT4]);
553 }
554 return(lastrand);
555}
556
557struct node *
558bflow(p)
559register struct node *p;
560{
561 register char *cp1,*cp2,**preg; register int r;
562 int flow= -1;
563 struct node *olduse=0;
564 splitrand(p);
565 if (p->op!=PUSH && p->subop && 0<=(r=isreg(lastrand)) && r<NUSE && uses[r]==p->forw) {
566 if (equtype(p->subop,regs[r][0])
567 || ((p->op==CVT || p->op==MOVZ)
568 && 0xf&regs[r][0] && compat(0xf&(p->subop>>4),regs[r][0]))) {
569 register int r2;
570 if (regs[r][1]!=0) {/* send directly to destination */
571 if (p->op==INC || p->op==DEC) {
572 if (p->op==DEC) p->op=SUB; else p->op=ADD;
573 p->subop=(OP2<<4)+(p->subop&0xF); /* use 2 now, convert to 3 later */
574 p->pop=0;
575 cp1=lastrand; cp2=regs[RT2]; while (*cp2++= *cp1++); /* copy reg */
576 cp1=lastrand; *cp1++='$'; *cp1++='1'; *cp1=0;
577 }
578 cp1=regs[r]+1; cp2=lastrand;
579 if (OP2==(p->subop>>4)) {/* use 3 operand form of instruction */
580 p->pop=0;
581 p->subop += (OP3-OP2)<<4; lastrand=cp2=regs[RT3];
582 }
583 while (*cp2++= *cp1++);
584 if (p->op==MOVA && p->forw->op==PUSH) {
585 p->op=PUSHA; *regs[RT2]=0; p->pop=0;
586 } else if (p->op==MOV && p->forw->op==PUSH) {
587 p->op=PUSH ; *regs[RT2]=0; p->pop=0;
588 }
589 delnode(p->forw);
590 if (0<=(r2=isreg(lastrand)) && r2<NUSE) {
591 uses[r2]=uses[r]; uses[r]=0;
592 }
593 redun3(p,0);
594 newcode(p); redunm++; flow=r;
595 } else if (p->op==MOV && p->forw->op!=EXTV && p->forw->op!=EXTZV) {
596 /* superfluous fetch */
597 int nmatch;
033bb901 598 char src[C2_ASIZE];
f00d91fc
BJ		 599 movit:
600 cp2=src; cp1=regs[RT1]; while (*cp2++= *cp1++);
601 splitrand(p->forw);
602 if (p->forw->op != INC && p->forw->op != DEC)
603 lastrand=byondrd(p->forw);
604 nmatch=0;
605 for (preg=regs+RT1;*preg!=lastrand;preg++)
606 if (r==isreg(*preg)) {
607 cp2= *preg; cp1=src; while (*cp2++= *cp1++); ++nmatch;
608 }
609 if (nmatch==1) {
610 if (OP2==(p->forw->subop>>4) && equstr(src,regs[RT2])) {
611 p->forw->pop=0;
612 p->forw->subop += (OP3-OP2)<<4; cp1=regs[RT3];
613 *cp1++='r'; *cp1++=r+'0'; *cp1=0;
614 }
615 delnode(p); p=p->forw;
616 if (0<=(r2=isreg(src)) && r2<NUSE) {
617 uses[r2]=uses[r]; uses[r]=0;
618 }
619 redun3(p,0);
620 newcode(p); redunm++; flow=r;
621 } else splitrand(p);
622 }
623 } else if (p->op==MOV && (p->forw->op==CVT || p->forw->op==MOVZ)
624 && p->forw->subop&0xf /* if base or index, then forget it */
625 && compat(p->subop,p->forw->subop) && !source(cp1=regs[RT1])
626 && !indexa(cp1)) goto movit;
627 }
628 /* adjust 'lastrand' past any 'read' or 'modify' operands. */
629 lastrand=byondrd(p);
630 /* a 'write' clobbers the register. */
631 if (0<=(r=isreg(lastrand)) && r<NUSE
632 || OP2==(p->subop>>4) && 0<=(r=isreg(regs[RT2])) && r<NUSE && uses[r]==0) {
633 /* writing a dead register is useless, but watch side effects */
634 switch (p->op) {
35307d30 635 case ACB:
f00d91fc 636 case AOBLEQ: case AOBLSS: case SOBGTR: case SOBGEQ: break;
35307d30 637 default:
f00d91fc
BJ		 638 if (uses[r]==0) {/* no direct uses, check for use of condition codes */
639 register struct node *q=p;
640 while ((q=nonlab(q->forw))->combop==JBR) q=q->ref; /* cc unused, unchanged */
641 if (q->op!=CBR) {/* ... and destroyed */
642 preg=regs+RT1;
643 while (cp1= *preg++) {
644 if (cp1==lastrand) {redunm++; delnode(p); return(p->forw);}
645 if (source(cp1) || equstr(cp1,lastrand)) break;
646 }
647 }
648 }
649 flow=r;
650 }
651 }
652 if (0<=(r=flow)) {olduse=uses[r]; uses[r]=0; *(short *)(regs[r])=0;}
653 /* these two are here, rather than in bmove(),
654 /* because I decided that it was better to go for 3-address code
655 /* (save time) rather than fancy jbxx (save 1 byte)
656 /* on sequences like bisl2 $64,r0; movl r0,foo
657 */
658 if (p->op==BIC) {p=bicopt(p); splitrand(p); lastrand=byondrd(p);}
659 if (p->op==BIS) {bixprep(p,JBSS); lastrand=byondrd(p);}
660 /* now look for 'read' or 'modify' (read & write) uses */
661 preg=regs+RT1;
662 while (*(cp1= *preg++)) {
663 /* check for r */
664 if (lastrand!=cp1 && 0<=(r=isreg(cp1)) && r<NUSE && uses[r]==0) {
665 uses[r]=p; cp2=regs[r]; *cp2++=p->subop;
d1580951 666 if (p->op==ASH && preg==(regs+RT1+1)) cp2[-1]=BYTE; /* stupid DEC */
f00d91fc
BJ		 667 if (p->op==MOV || p->op==PUSH || p->op==CVT || p->op==MOVZ || p->op==COM || p->op==NEG) {
668 if (p->op==PUSH) cp1="-(sp)";
669 else {
670 cp1=regs[RT2];
671 if (0<=(r=isreg(cp1)) && r<NUSE && uses[r]==0)
672 uses[r]=olduse; /* reincarnation!! */
673 /* as in addl2 r0,r1; movl r1,r0; ret */
674 if (p->op!=MOV) cp1=0;
675 }
676 if (cp1) while (*cp2++= *cp1++);
d1580951
BJ		 677 else *cp2=0;
678 } else *cp2=0;
f00d91fc
BJ		 679 continue;
680 }
681 /* check for (r),(r)+,-(r),[r] */
682 do if (*cp1=='(' || *cp1=='[') {/* get register number */
683 char t;
684 cp2= ++cp1; while (*++cp1!=')' && *cp1!=']'); t= *cp1; *cp1=0;
685 if (0<=(r=isreg(cp2)) && r<NUSE && (uses[r]==0 || uses[r]==p)) {
686 uses[r]=p; regs[r][0]=(*--cp2=='[' ? OPX<<4 : OPB<<4);
687 }
688 *cp1=t;
689 } while (*++cp1);
690 }
691 /* pushax or movax possibility? */
692 cp1=regs[RT1];
693 if (*cp1++=='$' && isstatic(cp1) && natural(regs[RT1])) {
694 if (p->combop==T(MOV,LONG)) {
695 if (regs[RT1][1]=='L' && 0!=(p->labno=getnum(regs[RT1]+2))) {
696 cp1=p->code; while (*cp1++!=','); p->code= --cp1;
697 }
698 p->combop=T(MOVA,LONG); ++p->code; p->pop=0;
699 } else if (p->combop==T(PUSH,LONG)) {
700 p->combop=T(PUSHA,LONG); ++p->code; p->pop=0;
701 } else if ((p->combop&0xFFFF)==T(ADD,U(LONG,OP3))
702 && 0<=(r=isreg(regs[RT2]))) {
703 cp1=cp2=p->code; ++cp1;
704 do *cp2++= *cp1; while (*cp1++!=','); cp2[-1]='[';
705 do *cp2++= *cp1; while (*cp1++!=','); cp2[-1]=']';
706 if (!equstr(regs[RT3],"-(sp)")) p->combop=T(MOVA,BYTE);
707 else {p->combop=T(PUSHA,BYTE); *cp2=0;}
708 if (uses[r]==0) {uses[r]=p; regs[r][0]=OPX<<4;}
709 p->pop=0;
710 }
711 }
712 return(p);
713}
714
715ispow2(n) register long n; {/* -1 -> no; else -> log to base 2 */
716 register int log;
717 if (n==0 || n&(n-1)) return(-1); log=0;
718 for (;;) {n >>= 1; if (n==0) return(log); ++log; if (n== -1) return(log);}
719}
720
721bitopt(p) register struct node *p; {
722 /* change "bitx $<power_of_2>,a" followed by JEQ or JNE
723 /* into JBC or JBS. watch out for I/O registers. (?)
724 /* assumes that 'splitrand' has already been called.
725 */
726 register char *cp1,*cp2; int b;
727 cp1=regs[RT1]; cp2=regs[RT2];
728 if (*cp1++!='$' || !okio(cp2) || p->forw->op!=CBR || p->forw->subop&-2 ||
729 0>(b=ispow2(getnum(cp1))) ||
730 p->subop!=BYTE && (source(cp2) || indexa(cp2))) return;
731 if (b>=bitsize[p->subop]) {/* you dummy! */
732 if (source(cp2)) {/* side effect: auto increment or decrement */
733 p->pop=0;
734 p->op=TST; --cp1; while (*cp1++= *cp2++);
735 regs[RT2][0]=0; newcode(p);
736 } else delnode(p);
737 p = p->forw;
738 if (p->subop==JEQ) {p->combop=JBR; p->pop=0;}
739 else delnode(p);
740 nchange++; nbj++; return;
741 }
742 if (cp1=p->forw->code) {/* destination is not an internal label */
743 cp2=regs[RT3]; while (*cp2++= *cp1++);
744 }
745 if (b==0 && (p->subop==LONG || !indexa(regs[RT2]))) {/* JLB optimization, ala BLISS */
746 cp2=regs[RT1]; cp1=regs[RT2]; while (*cp2++= *cp1++);
747 cp2=regs[RT2]; cp1=regs[RT3]; while (*cp2++= *cp1++);
748 *(regs[RT3])=0; p->forw->subop += JLBC-JBC;
749 p->forw->pop=0;
750 } else {
751 cp1=regs[RT1]+1;
752 if (b>9) *cp1++= b/10 +'0'; *cp1++= b%10 +'0'; *cp1=0; /* $<bit_number> */
753 }
754 nbj++; newcode(p); p->combop = p->forw->combop+((JBC-JEQ)<<8);
755 p->labno = p->forw->labno; delnode(p->forw);
756 p->pop=0;
757}
758
759isfield(n) register long n; {/* -1 -> no; else -> position of low bit */
760 register int pos; register long t;
761 t= ((n-1)|n) +1;
762 if (n!=0 && (0==t || 0==n || 0<=ispow2(t))) {
763 pos=0; while(!(n&1)) {n >>= 1; ++pos;} return(pos);
764 } else return(-1);
765}
766
767bixprep(p,bix) register struct node *p; {
768/* initial setup, single-bit checking for bisopt, bicopt.
769/* return: 0->don't bother any more; 1->worthwhile trying
770*/
771 register char *cp1,*cp2;
772 splitrand(p); cp1=regs[RT1]; cp2=regs[RT2];
773 if (*cp1++!='$' || 0>(pos=isfield(f=getnum(cp1)))
774 || !okio(cp2) || indexa(cp2) || source(cp2) || !okio(lastrand)) return(0);
775 f |= f-1; if (++f==0) siz=32-pos; else siz=ispow2(f)-pos;
776 if (siz==1 && pos>5 && (p->subop>>4)==OP2 && (p->subop&0xF)!=BYTE
777 && pos<bitsize[p->subop&0xF]) {
778 p->ref = insertl(p->forw); p->combop = CBR | (bix<<8);
779 p->pop=0;
780 p->labno = p->ref->labno;
781 if (pos>9) {*cp1++= pos/10 +'0'; pos %= 10;}
782 *cp1++=pos+'0'; *cp1=0; newcode(p); nbj++; return(0);
783 }
784 return(1);
785}
786
787
788struct node *
789bicopt(p) register struct node *p; {
790/* use field operations or MOVZ if possible. done as part of 'bflow'.
791*/
792 register char *cp1,*cp2; int r;
3b60efae 793 char src[C2_ASIZE];
49c27f9c 794 char lhssiz, subop;
f00d91fc
BJ		 795 if (!bixprep(p,JBCC)) return(p);
796 if (f==0) {/* the BIC isolates low order bits */
797 siz=pos; pos=0;
798 if ((p->subop&0xF)==LONG && *(regs[RT2])!='$') {/* result of EXTZV is long */
799 /* save source of BICL in 'src' */
800 cp1=regs[RT2]; cp2=src; while (*cp2++= *cp1++);
801 if (p->back->op==ASH) {/* try for more */
802 splitrand(p->back); cp1=regs[RT1]; cp2=regs[RT3];
803 if (*cp1++=='$' && *(regs[RT2])!='$' && !indexa(regs[RT2])
804 && 0>(f=getnum(cp1)) && equstr(src,cp2)
805 && 0<=(r=isreg(cp2)) && r<NUSE) {/* a good ASH */
806 pos -= f; cp1=regs[RT2]; cp2=src; while (*cp2++= *cp1++);
807 delnode(p->back);
808 }
809 }
49c27f9c
RC		 810 /*
811 * 'pos', 'siz' known; find out the size of the
812 * left-hand operand of what the bicl will turn into.
813 */
814 if (pos==0 && siz==16)
815 lhssiz = WORD; /* movzwl */
816 else
817 lhssiz = BYTE; /* movzbl or extzvl */
f00d91fc
BJ		 818 if (p->back->op==CVT || p->back->op==MOVZ) {/* greedy, aren't we? */
819 splitrand(p->back); cp1=regs[RT1]; cp2=regs[RT2];
49c27f9c
RC		 820 /*
821 * If indexa(cp1) || autoid(cp1), the fold may
822 * still be OK if the CVT/MOVZ has the same
823 * size operand on its left size as what we
824 * will turn the bicl into.
825 * However, if the CVT is from a float or
826 * double, forget it!
827 */
828 subop = p->back->subop&0xF; /* type of LHS of CVT/MOVZ */
829 if (equstr(src,cp2) && okio(cp1)
830 && subop != FFLOAT && subop != DFLOAT
831 && subop != GFLOAT && subop != HFLOAT
832 && ((!indexa(cp1) && !autoid(cp1)) || lhssiz == subop)
f00d91fc
BJ		 833 && 0<=(r=isreg(cp2)) && r<NUSE
834 && bitsize[p->back->subop&0xF]>=(pos+siz)
835 && bitsize[p->back->subop>>4]>=(pos+siz)) {/* good CVT */
836 cp1=regs[RT1]; cp2=src; while (*cp2++= *cp1++);
837 delnode(p->back);
838 }
839 }
840 /* 'pos', 'siz' known; source of field is in 'src' */
841 splitrand(p); /* retrieve destination of BICL */
49c27f9c
RC		 842 if ((siz==8 || siz==16) && pos==0) {
843 p->combop = T(MOVZ,U(lhssiz,LONG));
f00d91fc
BJ		 844 sprintf(line,"%s,%s",src,lastrand);
845 } else {
846 p->combop = T(EXTZV,LONG);
847 sprintf(line,"$%d,$%d,%s,%s",pos,siz,src,lastrand);
848 }
849 p->pop=0;
850 p->code = copy(line); nfield++; return(p);
851 }/* end EXTZV possibility */
852 }/* end low order bits */
853/* unfortunately, INSV clears the condition codes, thus cannot be used */
854/* else {/* see if BICL2 of positive field should be INSV $0 */
855/* if (p->subop==(LONG | (OP2<<4)) && 6<=(pos+siz)) {
856/* p->combop = INSV;
857/* sprintf(line,"$0,$%d,$%d,%s",pos,siz,lastrand);
858/* p->code = copy(line); nfield++; return(p);
859/* }
860/* }
861*/
862 return(p);
863}
864
865jumpsw()
866{
867 register struct node *p, *p1;
868 register t;
869 int nj;
870
871 t = 0;
872 nj = 0;
873 for (p=first.forw; p!=0; p = p->forw)
874 p->seq = ++t;
875 for (p=first.forw; p!=0; p = p1) {
876 p1 = p->forw;
877 if (p->op == CBR && p1->op==JBR && p->ref && p1->ref
878 && abs(p->seq - p->ref->seq) > abs(p1->seq - p1->ref->seq)) {
879 if (p->ref==p1->ref)
880 continue;
881 p->subop = revbr[p->subop];
882 p->pop=0;
883 t = p1->ref;
884 p1->ref = p->ref;
885 p->ref = t;
886 t = p1->labno;
887 p1->labno = p->labno;
888 p->labno = t;
889#ifdef COPYCODE
890 if (p->labno == 0) {
891 t = p1->code; p1->code = p->code; p->code = t;
892 }
893#endif
894 nrevbr++;
895 nj++;
896 }
897 }
898 return(nj);
899}
900
901addsob()
902{
903 register struct node *p, *p1, *p2, *p3;
904
905 for (p = &first; (p1 = p->forw)!=0; p = p1) {
906 if (p->combop==T(DEC,LONG) && p1->op==CBR) {
3b60efae 907 if (abs(p->seq - p1->ref->seq) > 8) continue;
f00d91fc
BJ		 908 if (p1->subop==JGE || p1->subop==JGT) {
909 if (p1->subop==JGE) p->combop=SOBGEQ; else p->combop=SOBGTR;
910 p->pop=0;
911 p->labno = p1->labno; delnode(p1); nsob++;
912 }
913 } else if (p->combop==T(INC,LONG)) {
914 if (p1->op==LABEL && p1->refc==1 && p1->forw->combop==T(CMP,LONG)
915 && (p2=p1->forw->forw)->combop==T(CBR,JLE)
916 && (p3=p2->ref->back)->combop==JBR && p3->ref==p1
917 && p3->forw->op==LABEL && p3->forw==p2->ref) {
918 /* change INC LAB: CMP to LAB: INC CMP */
919 p->back->forw=p1; p1->back=p->back;
920 p->forw=p1->forw; p1->forw->back=p;
921 p->back=p1; p1->forw=p;
922 p1=p->forw;
923 /* adjust beginning value by 1 */
924 p2=alloc(sizeof first); p2->combop=T(DEC,LONG);
925 p2->pop=0;
926 p2->forw=p3; p2->back=p3->back; p3->back->forw=p2;
927 p3->back=p2; p2->code=p->code; p2->labno=0;
928 }
929 if (p1->combop==T(CMP,LONG) && (p2=p1->forw)->op==CBR) {
930 register char *cp1,*cp2;
931 splitrand(p1); if (!equstr(p->code,regs[RT1])) continue;
3b60efae 932 if (abs(p->seq - p2->ref->seq)>8) {/* outside byte displ range */
f00d91fc
BJ		 933 if (p2->subop!=JLE) continue;
934 p->combop=T(ACB,LONG);
935 cp2=regs[RT1]; cp1=regs[RT2]; while (*cp2++= *cp1++); /* limit */
936 cp2=regs[RT2]; cp1="$1"; while (*cp2++= *cp1++); /* increment */
937 cp2=regs[RT3]; cp1=p->code; while (*cp2++= *cp1++); /* index */
938 p->pop=0; newcode(p);
939 p->labno = p2->labno; delnode(p2); delnode(p1); nsob++;
940 } else if (p2->subop==JLE || p2->subop==JLT) {
941 if (p2->subop==JLE) p->combop=AOBLEQ; else p->combop=AOBLSS;
942 cp2=regs[RT1]; cp1=regs[RT2]; while (*cp2++= *cp1++); /* limit */
943 cp2=regs[RT2]; cp1=p->code; while (*cp2++= *cp1++); /* index */
944 p->pop=0; newcode(p);
945 p->labno = p2->labno; delnode(p2); delnode(p1); nsob++;
946 }
947 }
948 }
949 }
950}
951
952abs(x)
953{
954 return(x<0? -x: x);
955}
956
957equop(p1, p2)
958register struct node *p1;
959struct node *p2;
960{
961 register char *cp1, *cp2;
962
963 if (p1->combop != p2->combop)
964 return(0);
965 if (p1->op>0 && p1->op<MOV)
966 return(0);
967 if (p1->op==MOVA && p1->labno!=p2->labno) return(0);
968 cp1 = p1->code;
969 cp2 = p2->code;
970 if (cp1==0 && cp2==0)
971 return(1);
972 if (cp1==0 || cp2==0)
973 return(0);
974 while (*cp1 == *cp2++)
975 if (*cp1++ == 0)
976 return(1);
977 return(0);
978}
979
980delnode(p) register struct node *p; {
981 p->back->forw = p->forw;
982 p->forw->back = p->back;
983}
984
985decref(p)
986register struct node *p;
987{
988 if (p && --p->refc <= 0) {
989 nrlab++;
990 delnode(p);
991 }
992}
993
994struct node *
995nonlab(ap)
996struct node *ap;
997{
998 register struct node *p;
999
1000 p = ap;
1001 while (p && p->op==LABEL)
1002 p = p->forw;
1003 return(p);
1004}
1005
1006clearuse() {
1007 register struct node **i;
1008 for (i=uses+NUSE; i>uses;) *--i=0;
1009}
1010
1011clearreg() {
1012 register short **i;
1013 for (i=regs+NREG; i>regs;) **--i=0;
1014 conloc[0] = 0; ccloc[0] = 0;
1015}
1016
1017savereg(ai, s, type)
1018register char *s;
1019{
1020 register char *p, *sp;
1021
1022 sp = p = regs[ai];
1023 if (source(s)) /* side effects in addressing */
1024 return;
1025 /* if any indexing, must be parameter or local */
1026 /* indirection (as in "*-4(fp)") is ok, however */
1027 *p++ = type;
1028 while (*p++ = *s)
1029 if (*s=='[' || *s++=='(' && *s!='a' && *s!='f') {*sp = 0; return;}
1030}
1031
1032dest(s,type)
1033register char *s;
1034{
1035 register int i;
1036
1037 source(s); /* handle addressing side effects */
1038 if ((i = isreg(s)) >= 0) {
1039 *(short *)(regs[i]) = 0; /* if register destination, that reg is a goner */
0594fe30
BJ		 1040 switch(type & 0xF){
1041 case DFLOAT: /* clobber two at once */
1042 /*FALLTHROUGH*/
1043 case GFLOAT:
1044 *(short *)(regs[i+1]) = 0;
1045 break;
1046 case HFLOAT: /* clobber four at once */
1047 *(short *)(regs[i+1]) = 0;
1048 *(short *)(regs[i+2]) = 0;
1049 *(short *)(regs[i+3]) = 0;
1050 break;
1051 }
1052 switch((type>>4)&0xF){
1053 case DFLOAT: /* clobber two at once */
1054 /*FALLTHROUGH*/
1055 case GFLOAT:
1056 *(short *)(regs[i+1]) = 0;
1057 break;
1058 case HFLOAT: /* clobber four at once */
1059 *(short *)(regs[i+1]) = 0;
1060 *(short *)(regs[i+2]) = 0;
1061 *(short *)(regs[i+3]) = 0;
1062 break;
1063 }
1064 /*
1065 if (DFLOAT==(type&0xF) || DFLOAT==((type>>4)&0xF))
1066 *(short *)(regs[i+1]) = 0;
1067 */
f00d91fc
BJ		 1068 }
1069 for (i=NREG; --i>=0;)
1070 if (regs[i][1]=='*' && equstr(s, regs[i]+2))
1071 *(short *)(regs[i]) = 0; /* previous indirection through destination is invalid */
1072 while ((i = findrand(s,0)) >= 0) /* previous values of destination are invalid */
1073 *(short *)(regs[i]) = 0;
1074 if (!natural(s)) {/* wild store, everything except constants vanishes */
1075 for (i=NREG; --i>=0;) if (regs[i][1] != '$') *(short *)(regs[i]) = 0;
1076 conloc[0] = 0; ccloc[0] = 0;
1077 } else setcc(s,type); /* natural destinations set condition codes */
1078}
1079
1080splitrand(p) struct node *p; {
1081/* separate operands at commas, set up 'regs' and 'lastrand' */
1082register char *p1, *p2; register char **preg;
1083preg=regs+RT1;
1084if (p1=p->code) while (*p1) {
1085 lastrand=p2= *preg++;
1086 while (*p1) if (','==(*p2++= *p1++)) {--p2; break;}
1087 *p2=0;
1088}
1089while (preg<(regs+RT1+5)) *(*preg++)=0;
1090}
1091
1092compat(have, want) {
1093register int hsrc, hdst;
1094if (0==(want &= 0xF)) return(1); /* anything satisfies a wildcard want */
1095hsrc=have&0xF; if (0==(hdst=((have>>4)&0xF)) || hdst>=OP2) hdst=hsrc;
0594fe30
BJ		 1096if (want>=FFLOAT) return(hdst==want && hsrc==want);
1097 /* FLOAT, DFLOAT not compat: rounding */
1098return(hsrc>=want && hdst>=want && hdst<FFLOAT);
f00d91fc
BJ		 1099}
1100
1101equtype(t1,t2) {return(compat(t1,t2) && compat(t2,t1));}
1102
1103findrand(as, type)
1104char *as;
1105{
1106 register char **i;
1107 for (i = regs+NREG; --i>=regs;) {
1108 if (**i && equstr(*i+1, as) && compat(**i,type))
1109 return(i-regs);
1110 }
1111 return(-1);
1112}
1113
1114isreg(s)
1115register char *s;
1116{
1117 if (*s++!='r' || !isdigit(*s++)) return(-1);
1118 if (*s==0) return(*--s-'0');
1119 if (*(s-1)=='1' && isdigit(*s++) && *s==0) return(10+*--s-'0');
1120 return(-1);
1121}
1122
1123check()
1124{
1125 register struct node *p, *lp;
1126
1127 lp = &first;
1128 for (p=first.forw; p!=0; p = p->forw) {
1129 if (p->back != lp)
1130 abort(-1);
1131 lp = p;
1132 }
1133}
1134
1135source(ap)
1136char *ap;
1137{
1138 register char *p1, *p2;
1139
1140 p1 = ap;
1141 p2 = p1;
1142 if (*p1==0)
1143 return(0);
1144 while (*p2++ && *(p2-1)!='[');
1145 if (*p1=='-' && *(p1+1)=='('
1146 || *p1=='*' && *(p1+1)=='-' && *(p1+2)=='('
1147 || *(p2-2)=='+') {
1148 while (*p1 && *p1++!='r');
1149 if (isdigit(*p1++))
1150 if (isdigit(*p1)) *(short *)(regs[10+*p1-'0'])=0;
1151 else *(short *)(regs[*--p1-'0'])=0;
1152 return(1);
1153 }
1154 return(0);
1155}
1156
1157newcode(p) struct node *p; {
1158 register char *p1,*p2,**preg;
1159 preg=regs+RT1; p2=line;
1160 while (*(p1= *preg++)) {while (*p2++= *p1++); *(p2-1)=',';}
1161 *--p2=0;
1162 p->code=copy(line);
1163}
1164
1165repladdr(p)
1166struct node *p;
1167{
1168 register r;
1169 register char *p1, *p2;
1170 char **preg; int nrepl;
1171
1172 preg=regs+RT1; nrepl=0;
1173 while (lastrand!=(p1= *preg++))
1174 if (!source(p1) && 0<=(r=findrand(p1,p->subop))) {
1175 *p1++='r'; if (r>9) {*p1++='1'; r -= 10;} *p1++=r+'0'; *p1=0;
1176 nrepl++; nsaddr++;
1177 }
1178 if (nrepl) newcode(p);
1179}
1180
1181/* movedat()
1182/* {
1183/* register struct node *p1, *p2;
1184/* struct node *p3;
1185/* register seg;
1186/* struct node data;
1187/* struct node *datp;
1188/*
1189/* if (first.forw == 0)
1190/* return;
1191/* datp = &data;
1192/* for (p1 = first.forw; p1!=0; p1 = p1->forw) {
1193/* if (p1->op == DATA) {
1194/* p2 = p1->forw;
1195/* while (p2 && p2->op!=TEXT)
1196/* p2 = p2->forw;
1197/* if (p2==0)
1198/* break;
1199/* p3 = p1->back;
1200/* p1->back->forw = p2->forw;
1201/* p2->forw->back = p3;
1202/* p2->forw = 0;
1203/* datp->forw = p1;
1204/* p1->back = datp;
1205/* p1 = p3;
1206/* datp = p2;
1207/* }
1208/* }
1209/* if (data.forw) {
1210/* datp->forw = first.forw;
1211/* first.forw->back = datp;
1212/* data.forw->back = &first;
1213/* first.forw = data.forw;
1214/* }
1215/* seg = -1;
1216/* for (p1 = first.forw; p1!=0; p1 = p1->forw) {
1217/* if (p1->op==TEXT||p1->op==DATA||p1->op==BSS) {
1218/* if (p1->op == seg || p1->forw&&p1->forw->op==seg) {
1219/* p1->back->forw = p1->forw;
1220/* p1->forw->back = p1->back;
1221/* p1 = p1->back;
1222/* continue;
1223/* }
1224/* seg = p1->op;
1225/* }
1226/* }
1227/* }
1228*/
1229
1230redunbr(p)
1231register struct node *p;
1232{
1233 register struct node *p1;
1234 register char *ap1;
1235 char *ap2;
1236
1237 if ((p1 = p->ref) == 0)
1238 return;
1239 p1 = nonlab(p1);
1240 if (p1->op==TST) {
1241 splitrand(p1);
1242 savereg(RT2, "$0", p1->subop);
1243 } else if (p1->op==CMP)
1244 splitrand(p1);
1245 else
1246 return;
1247 if (p1->forw->op==CBR) {
1248 ap1 = findcon(RT1, p1->subop);
1249 ap2 = findcon(RT2, p1->subop);
1250 p1 = p1->forw;
1251 if (compare(p1->subop, ap1, ap2)) {
1252 nredunj++;
1253 nchange++;
1254 decref(p->ref);
1255 p->ref = p1->ref;
1256 p->labno = p1->labno;
1257#ifdef COPYCODE
1258 if (p->labno == 0)
1259 p->code = p1->code;
1260 if (p->ref)
1261#endif
1262 p->ref->refc++;
1263 }
1264 } else if (p1->op==TST && equstr(regs[RT1],ccloc+1) &&
1265 equtype(ccloc[0],p1->subop)) {
1266 p1=insertl(p1->forw); decref(p->ref); p->ref=p1;
1267 nrtst++; nchange++;
1268 }
1269}
1270
1271char *
1272findcon(i, type)
1273{
1274 register char *p;
1275 register r;
1276
1277 p = regs[i];
1278 if (*p=='$')
1279 return(p);
1280 if ((r = isreg(p)) >= 0 && compat(regs[r][0],type))
1281 return(regs[r]+1);
1282 if (equstr(p, conloc))
1283 return(conval+1);
1284 return(p);
1285}
1286
1287compare(op, acp1, acp2)
1288char *acp1, *acp2;
1289{
1290 register char *cp1, *cp2;
1291 register n1;
1292 int n2; int sign;
1293
1294 cp1 = acp1;
1295 cp2 = acp2;
1296 if (*cp1++ != '$' || *cp2++ != '$')
1297 return(0);
1298 n1 = 0; sign=1; if (*cp2=='-') {++cp2; sign= -1;}
1299 while (isdigit(*cp2)) {n1 *= 10; n1 += (*cp2++ - '0')*sign;}
1300 n2 = n1;
1301 n1 = 0; sign=1; if (*cp1=='-') {++cp1; sign= -1;}
1302 while (isdigit(*cp1)) {n1 *= 10; n1 += (*cp1++ - '0')*sign;}
1303 if (*cp1=='+')
1304 cp1++;
1305 if (*cp2=='+')
1306 cp2++;
1307 do {
1308 if (*cp1++ != *cp2)
1309 return(0);
1310 } while (*cp2++);
1311 cp1 = n1;
1312 cp2 = n2;
1313 switch(op) {
1314
1315 case JEQ:
1316 return(cp1 == cp2);
1317 case JNE:
1318 return(cp1 != cp2);
1319 case JLE:
1320 return(((int)cp1) <= ((int)cp2));
1321 case JGE:
1322 return(((int)cp1) >= ((int)cp2));
1323 case JLT:
1324 return(((int)cp1) < ((int)cp2));
1325 case JGT:
1326 return(((int)cp1) > ((int)cp2));
1327 case JLO:
1328 return(cp1 < cp2);
1329 case JHI:
1330 return(cp1 > cp2);
1331 case JLOS:
1332 return(cp1 <= cp2);
1333 case JHIS:
1334 return(cp1 >= cp2);
1335 }
1336 return(0);
1337}
1338
1339setcon(cv, cl, type)
1340register char *cv, *cl;
1341{
1342 register char *p;
1343
1344 if (*cv != '$')
1345 return;
1346 if (!natural(cl))
1347 return;
1348 p = conloc;
1349 while (*p++ = *cl++);
1350 p = conval;
1351 *p++ = type;
1352 while (*p++ = *cv++);
1353}
1354
1355equstr(p1, p2)
1356register char *p1, *p2;
1357{
1358 do {
1359 if (*p1++ != *p2)
1360 return(0);
1361 } while (*p2++);
1362 return(1);
1363}
1364
1365setcc(ap,type)
1366char *ap;
1367{
1368 register char *p, *p1;
1369
1370 p = ap;
1371 if (!natural(p)) {
1372 ccloc[0] = 0;
1373 return;
1374 }
1375 p1 = ccloc;
1376 *p1++ = type;
1377 while (*p1++ = *p++);
1378}
1379
1380okio(p) register char *p; {/* 0->probable I/O space address; 1->not */
1381 if (ioflag && (!natural(p) || 0>getnum(p))) return(0);
1382 return(1);
1383}
1384
1385indexa(p) register char *p; {/* 1-> uses [r] addressing mode; 0->doesn't */
1386 while (*p) if (*p++=='[') return(1);
1387 return(0);
1388}
1389
1390natural(p)
1391register char *p;
1392{/* 1->simple local, parameter, global, or register; 0->otherwise */
1393 if (*p=='*' || *p=='(' || *p=='-'&&*(p+1)=='(' || *p=='$'&&getnum(p+1))
1394 return(0);
1395 while (*p++);
1396 p--;
1397 if (*--p=='+' || *p==']' || *p==')' && *(p-2)!='a' && *(p-2)!='f')
1398 return(0);
1399 return(1);
1400}
1401
1402/*
1403** Tell if an argument is most likely static.
1404*/
1405
1406isstatic(cp)
1407register char *cp;
1408{
1409 if (*cp == '_' || *cp == 'L' || (*cp++ == 'v' && *cp == '.'))
1410 return (1);
1411 return (0);
1412}
49c27f9c
RC		 1413
1414autoid(p) register char *p; {/* 1-> uses autoincrement/autodecrement; 0->doesn't */
1415 if (*p == '-' && *(p+1) == '(') return(1);
1416 while (*p) p++;
1417 if (*--p == '+' && *--p == ')') return(1);
1418 return(0);
1419 }
Continuous source code history from original PDP-7 UNIX to FreeBSD 2, the first fully unencumbered FreeBSD release.