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lint changes from donn@utah-cs.
[unix-history] / usr / src / old / pcc / c2.vax / c21.c
CommitLineData
41feb04a
RC		 1#ifndef lint
2static char sccsid[] = "@(#)c21.c 4.15 %G%";
3#endif
35307d30 4/* char C21[] = {"@(#)c21.c 1.83 80/10/16 21:18:22 JFR"}; /* sccs ident */
f00d91fc
BJ		 5
6/*
7 * C object code improver-- second part
8 */
9
10#include "c2.h"
11#include <stdio.h>
12#include <ctype.h>
13
14#define NUSE 6
15int ioflag;
16int biti[NUSE] = {1,2,4,8,16,32};
0594fe30 17int bitsize[] = { /* index by type codes */
a24e0abe
RH		 18 0, /* 0 not allocated */
19 8, /* 1 BYTE */
20 16, /* 2 WORD */
21 32, /* 3 LONG */
22 32, /* 4 FFLOAT /
23 64, /* 5 DFLOAT */
24 64, /* 6 QUAD */
25 0, /* 7 OP2 */
26 0, /* 8 OP3 */
27 0, /* 9 OPB */
28 0, /* 10 OPX */
29 64, /* 11 GFLOAT */
30 128, /* 12 HFLOAT */
31 128 /* 13 OCTA */
0594fe30 32};
f00d91fc
BJ		 33int pos,siz; long f; /* for bit field communication */
34struct node *uses[NUSE]; /* for backwards flow analysis */
35char *lastrand; /* last operand of instruction */
36struct node *bflow();
37struct node *bicopt();
38char *findcon();
41feb04a 39char *strcpy();
f00d91fc
BJ		 40
41redun3(p,split) register struct node *p; int split; {
42/* check for 3 addr instr which should be 2 addr */
43 if (OP3==((p->subop>>4)&0xF)) {
44 if (split) splitrand(p);
45 if (equstr(regs[RT1],regs[RT3])
46 && (p->op==ADD || p->op==MUL || p->op==BIS || p->op==XOR)) {
47 register char *t=regs[RT1]; regs[RT1]=regs[RT2]; regs[RT2]=t;
48 }
49 if (equstr(regs[RT2],regs[RT3])) {
50 p->subop=(p->subop&0xF)|(OP2<<4); p->pop=0;
51 lastrand=regs[RT2]; *regs[RT3]=0; return(1);
52 }
53 } return(0);
54}
55
56bmove() {
57 register struct node *p, *lastp; register char *cp1,*cp2; register int r;
58 refcount();
59 for (p=lastp= &first; 0!=(p=p->forw); lastp=p);
60 clearreg(); clearuse();
61 for (p=lastp; p!= &first; p=p->back) {
62 if (debug) {
63 printf("Uses:\n");
64 for (r=NUSE;--r>=0;) if (uses[r])
65 printf("%d: %s\n",r,uses[r]->code? uses[r]->code:"");
66 printf("-\n");
67 }
68 r=(p->subop>>4)&0xF;
69 if (OP2==r && (cp1=p->code, *cp1++)=='$' && *cp1++=='0' && *cp1++==',' &&
70 !source(cp1)) {/* a no-op unless MUL or DIV */
71 if (p->op==MUL) {p->op=MOV; p->subop&=0xF; p->pop=0;}
72 else if (p->op==DIV) fprintf(stderr,"c2: zero divide\n");
73 else {delnode(p); redunm++; continue;}
74 }
75 if (OP3==r && 0!=redun3(p,1)) {newcode(p); redunm++;}
76 switch (p->op) {
77 case LABEL: case DLABEL:
78 for (r=NUSE; --r>=0;)
79 if (uses[r]) p->ref=(struct node *) (((int)p->ref)|biti[r]);
80 break;
81 case CALLS:
82 clearuse(); goto std;
83 case 0:
11850887
RC		 84 /*
85 * Be conservative -- if we don't know what it is, then we
86 * assume that it can set anything.
87 */
88 for ( r = 0; r < NUSE; ++r )
89 uses[r] = p;
90 break;
f00d91fc
BJ		 91 case SUB:
92 if ((p->subop&0xF)!=LONG) goto std; cp1=p->code;
93 if (*cp1++!='$') goto std; splitrand(p);
94 if (equstr(regs[RT2],"fp") && !indexa(regs[RT1])) {/* address comp. */
3b60efae 95 char buf[C2_ASIZE]; cp2=buf; *cp2++='-';
f00d91fc
BJ		 96 cp1=regs[RT1]+1; while (*cp2++= *cp1++); --cp2;
97 cp1="(fp),"; while (*cp2++= *cp1++); --cp2;
98 cp1=regs[RT3]; while (*cp2++= *cp1++);
99 p->code=copy(buf); p->combop=T(MOVA,LONG); p->pop=0;
100 } else if (*cp1++=='-' && 0<=(r=getnum(cp1))) {
101 p->op=ADD; p->pop=0; *--cp1='$'; p->code=cp1;
102 } goto std;
103 case ADD:
104 if ((p->subop&0xF)!=LONG) goto std; cp1=p->code;
105 if (*cp1++!='$') goto std; splitrand(p);
106 if (isstatic(cp1) && (r=isreg(regs[RT2]))>=0 && r<NUSE && uses[r]==p->forw)
107 {
108 /* address comp:
109 ** addl2 $_foo,r0 \ movab _foo[r0],bar
110 ** movl r0,bar /
111 */
112 register struct node *pnext = p->forw;
3b60efae 113 char buf[C2_ASIZE];
f00d91fc
BJ		 114
115 if (pnext->op == MOV && pnext->subop == LONG)
116 {
117 cp1 = &regs[RT1][1]; cp2 = &buf[0];
118 while (*cp2++ = *cp1++) ; cp2--;
119 splitrand(pnext);
120 if (r == isreg(regs[RT1]))
121 {
122 delnode(p); p = pnext;
123 p->op = MOVA; p->subop = BYTE;
124 p->pop = 0;
125 cp1 = regs[RT1]; *cp2++ = '[';
126 while (*cp2++ = *cp1++) ; cp2--;
127 *cp2++ = ']'; *cp2++ = ',';
128 cp1 = regs[RT2];
129 while (*cp2++ = *cp1++) ;
130 p->code = copy(buf);
131 }
132 }
133 }
134 else
135 if (equstr(regs[RT2],"fp") && !indexa(regs[RT1])) {/* address comp. */
136 cp2=cp1-1; cp1=regs[RT1]+1; while (*cp2++= *cp1++); --cp2;
137 cp1="(fp)"; while (*cp2++= *cp1++); *--cp2=',';
138 p->combop=T(MOVA,LONG); p->pop=0;
139 } else if (*cp1++=='-' && 0<=(r=getnum(cp1))) {
140 p->op=SUB; p->pop=0; *--cp1='$'; p->code=cp1;
141 }
142 /* fall thru ... */
143 case CASE:
144 default: std:
145 p=bflow(p); break;
146 case MUL:
147 {
148 /*
149 ** Change multiplication by constant powers of 2 to
150 ** shifts.
151 */
152 splitrand(p);
153 if (regs[RT1][0] != '$' || regs[RT1][1] == '-') goto std;
154 if ((r = ispow2(getnum(&regs[RT1][1]))) < 0) goto std;
155 switch (r)
156 {
157 case 0: /* mull3 $1,x,y */
158 if (p->subop == U(LONG,OP3))
159 {
160 if (equstr(regs[RT2], regs[RT3]))
161 {
162 delnode(p); p = p->forw;
163 }
164 else
165 {
166 p->op = MOV; p->subop = LONG;
167 p->pop = 0; newcode(p); nchange++;
168 }
169 }
170 else
171 if (p->subop == U(LONG,OP2))
172 {
173 delnode(p); p = p->forw;
174 }
175 goto std;
176
177 case 1: /* mull2 $2,x */
178 if (p->subop == U(LONG, OP2) && !source(regs[RT2]))
179 {
180 strcpy(regs[RT1], regs[RT2]);
181 p->op = ADD; p->pop = 0; newcode(p); nchange++;
182 }
183 goto std;
184 }
185 if(p->subop==U(LONG,OP3)||(p->subop==U(LONG,OP2)&&!source(regs[RT2])))
186 {
187 if (p->subop == U(LONG,OP2))
188 strcpy(regs[RT3], regs[RT2]);
189 sprintf(regs[RT1], "$%d", r);
190 p->op = ASH; p->subop = LONG;
191 p->pop = 0; newcode(p); nchange++;
192 }
193 goto std;
194 }
195 case ASH:
196 {
197 /* address comp:
198 ** ashl $1,bar,r0 \ movl bar,r0
199 ** movab _foo[r0] / movaw _foo[r0]
200 **
201 ** ashl $2,r0,r0 \ moval _foo[r0]
202 ** movab _foo[r0] /
203 */
204 register struct node *pf;
205 register int shfrom, shto;
206 long shcnt;
207 char *regfrom;
208
209 splitrand(p);
210 if (regs[RT1][0] != '$') goto std;
211 if ((shcnt = getnum(&regs[RT1][1])) < 1 || shcnt > 3) goto std;
212 if ((shfrom = isreg(regs[RT2])) >= 0)
41feb04a 213 regfrom = copy(regs[RT2]);
f00d91fc
BJ		 214 if ((shto = isreg(regs[RT3])) >= 0 && shto<NUSE)
215 {
216 int regnum;
217
218 if (uses[shto] != (pf = p->forw)) goto ashadd;
219 if (pf->op != MOVA && pf->op != PUSHA) goto ashadd;
220 if (pf->subop != BYTE) goto ashadd;
221 splitrand(pf);
222 if (!indexa(regs[RT1])) goto std;
223 cp2 = regs[RT1];
224 if(!isstatic(cp2)) goto std;
225 while (*cp2++ != '[') ;
226 if (*cp2++ != 'r' || !isdigit(*cp2)) goto std;
227 regnum = *cp2++ - '0';
228 if (isdigit(*cp2))
229 {
230 if (cp2[1] != ']') goto std;
231 regnum *= 10; regnum += *cp2 - '0';
232 }
233 if (regnum != shto) goto std;
234 if (shfrom >= 0) /* ashl $N,r*,r0 */
235 {
236 delnode(p);
237 if (shfrom != shto)
238 {
239 uses[shto] = NULL; splitrand(pf);
240 cp2=regs[RT1]; while (*cp2++!='[');
241 cp1=regfrom; while (*cp2++= *cp1++);
41feb04a
RC		 242 *--cp2 = ']';
243 *++cp2 = '\0';
f00d91fc
BJ		 244 newcode(pf);
245 }
246 }
247 else
248 {
249 p->op = MOV; splitrand(p);
250 strcpy(regs[RT1], regs[RT2]);
251 strcpy(regs[RT2], regs[RT3]);
252 regs[RT3][0] = '\0';
253 p->pop = 0; newcode(p);
254 }
255 switch (shcnt)
256 {
257 case 1: pf->subop = WORD; break;
258 case 2: pf->subop = LONG; break;
259 case 3: pf->subop = QUAD; break;
260 }
261 redunm++; nsaddr++; nchange++;
262 }
263 goto std;
264ashadd:
265 /* at this point, RT2 and RT3 are guaranteed to be simple regs*/
266 if (shcnt == 1 && equstr(regs[RT2], regs[RT3]))
267 {
268 /*
269 ** quickie:
270 ** ashl $1,A,A > addl2 A,A
271 */
272 p->op = ADD; p->subop = U(LONG,OP2); p->pop = 0;
273 strcpy(regs[RT1], regs[RT2]); regs[RT3][0] = '\0';
274 newcode(p); nchange++;
275 }
276 goto std;
277 }
278
279 case EXTV:
280 case EXTZV:
281 {
282 /* bit tests:
283 ** extv A,$1,B,rC \
284 ** tstl rC > jbc A,B,D
285 ** jeql D /
286 **
287 ** also byte- and word-size fields:
288 ** extv $n*8,$8,A,B > cvtbl n+A,B
49c27f9c 289 ** extv $n*16,$16,A,B > cvtwl 2n+A,B
f00d91fc 290 ** extzv $n*8,$8,A,B > movzbl n+A,B
49c27f9c 291 ** extzv $n*16,$16,A,B > movzwl 2n+A,B
f00d91fc
BJ		 292 */
293 register struct node *pf; /* forward node */
294 register struct node *pn; /* next node (after pf) */
295 int flen; /* field length */
296
297 splitrand(p);
298 if (regs[RT2][0] != '$') goto std;
299 if ((flen = getnum(&regs[RT2][1])) < 0) goto std;
300 if (flen == 1)
301 {
302 register int extreg; /* reg extracted to */
303
304 extreg = isreg(regs[RT4]);
305 if (extreg < 0 || extreg >= NUSE) goto std;
306 if ((pf = p->forw)->op != TST) goto std;
307 if (uses[extreg] && uses[extreg] != pf) goto std;
308 splitrand(pf);
309 if (extreg != isreg(regs[RT1])) goto std;
310 if ((pn = pf->forw)->op != CBR) goto std;
311 if (pn->subop != JEQ && pn->subop != JNE) goto std;
312 delnode(p); delnode(pf);
313 pn->subop = (pn->subop == JEQ) ? JBC : JBS;
314 for(cp2=p->code; *cp2++!=',';);
315 for(cp1=cp2; *cp1++!=',';);
316 while (*cp1!=',') *cp2++= *cp1++; *cp2='\0';
317 pn->code = p->code; pn->pop = NULL;
318 uses[extreg] = NULL;
319 }
320 else
321 if (flen == 8 || flen == 16)
322 {
323 register int boff; /* bit offset */
324 register int coff; /* chunk (byte or word) offset*/
325
326 if (regs[RT1][0] != '$') goto std;
327 if ((boff = getnum(&regs[RT1][1])) < 0) goto std;
328 coff = boff / flen;
329 if (coff && (isreg(regs[RT3]) >= 0)) goto std;
330 if (boff < 0 || (boff % flen) != 0) goto std;
331 p->op = (p->op == EXTV) ? CVT : MOVZ;
332 p->subop = U((flen == 8 ? BYTE : WORD), LONG);
333 if (coff == 0)
334 strcpy(regs[RT1], regs[RT3]);
335 else
49c27f9c
RC		 336 sprintf(regs[RT1], "%d%s%s",
337 (flen == 8 ? coff : 2*coff),
338 (regs[RT3][0] == '(' ? "" : "+"),
f00d91fc
BJ		 339 regs[RT3]);
340 strcpy(regs[RT2], regs[RT4]);
341 regs[RT3][0] = '\0'; regs[RT4][0] = '\0';
342 p->pop = 0; newcode(p);
343 }
344 nchange++;
345 goto std;
346 }
347
348 case CMP:
349 {
350 /* comparison to -63 to -1:
351 ** cmpl r0,$-1 > incl r0
352 ** jeql ...
353 **
354 ** cmpl r0,$-63 > addl2 $63,r0
355 ** jeql ...
356 */
357 register int num;
358 register int reg;
359 register struct node *regp = p->back;
360
361 if (p->forw->op != CBR) goto std;
362 if (p->forw->subop != JEQ && p->forw->subop != JNE) goto std;
363 splitrand(p);
364 if (strncmp(regs[RT2], "$-", 2) != 0) goto std;
365 reg = r = isreg(regs[RT1]);
366 if (r < 0) goto std;
367 if (r < NUSE && uses[r] != 0) goto std;
368 if (r >= NUSE && regp->op == MOV && p->subop == regp->subop)
369 {
370 if (*regp->code != 'r') goto std;
371 reg = regp->code[1] - '0';
372 if (isdigit(regp->code[2]) || reg >= NUSE || uses[reg])
373 goto std;
374 }
375 if (r >= NUSE) goto std;
376 if (reg != r)
377 sprintf(regs[RT1], "r%d", reg);
378 if ((num = getnum(&regs[RT2][2])) <= 0 || num > 63) goto std;
379 if (num == 1)
380 {
381 p->op = INC; regs[RT2][0] = '\0';
382 }
383 else
384 {
385 register char *t;
386
387 t=regs[RT1];regs[RT1]=regs[RT2];regs[RT2]=t;
388 p->op = ADD; p->subop = U(p->subop, OP2);
389 for (t = &regs[RT1][2]; t[-1] = *t; t++) ;
390 }
391 p->pop = 0; newcode(p);
392 nchange++;
393 goto std;
394 }
395
396 case JSB:
397 if (equstr(p->code,"mcount")) {uses[0]=p; regs[0][0]= -1;}
398 goto std;
399 case JBR: case JMP:
400 clearuse();
401 if (p->subop==RET || p->subop==RSB) {uses[0]=p; regs[0][0]= -1; break;}
402 if (p->ref==0) goto std; /* jmp (r0) */
403 /* fall through */
404 case CBR:
405 if (p->ref->ref!=0) for (r=NUSE;--r>=0;)
406 if (biti[r] & (int)p->ref->ref) {uses[r]=p; regs[r][0]= -1;}
407 case EROU: case JSW:
408 case TEXT: case DATA: case BSS: case ALIGN: case WGEN: case END: ;
409 }
410 }
411 for (p= &first; p!=0; p=p->forw)
412 if (p->op==LABEL || p->op==DLABEL) p->ref=0; /* erase our tracks */
413}
414
415rmove()
416{
41feb04a 417 register struct node *p;
f00d91fc
BJ		 418 register int r;
419 int r1;
420
421 clearreg();
422 for (p=first.forw; p!=0; p = p->forw) {
f00d91fc 423 if (debug) {
6b028d93
RC		 424 if (*conloc) {
425 r1=conval[0];
426 printf("Con %s = %d%d %s\n", conloc, r1&0xF, r1>>4, conval+1);
427 }
f00d91fc
BJ		 428 printf("Regs:\n");
429 for (r=0; r<NREG; r++)
430 if (regs[r][0]) {
431 r1=regs[r][0];
432 printf("%d: %d%d %s\n", r, r1&0xF, r1>>4, regs[r]+1);
433 }
434 printf("-\n");
435 }
436 switch (p->op) {
437
438 case CVT:
439 splitrand(p); goto mov;
440
441 case MOV:
442 splitrand(p);
443 if ((r = findrand(regs[RT1],p->subop)) >= 0) {
444 if (r == isreg(regs[RT2]) && p->forw->op!=CBR) {
445 delnode(p); redunm++; break;
446 }
447 }
448mov:
449 repladdr(p);
450 r = isreg(regs[RT1]);
451 r1 = isreg(regs[RT2]);
452 dest(regs[RT2],p->subop);
d1580951
BJ		 453 if (r>=0) {
454 if (r1>=0) savereg(r1, regs[r]+1, p->subop);
455 else if (p->op!=CVT) savereg(r, regs[RT2], p->subop);
456 } else if (r1>=0) savereg(r1, regs[RT1], p->subop);
457 else if (p->op!=CVT) setcon(regs[RT1], regs[RT2], p->subop);
f00d91fc
BJ		 458 break;
459
460/* .rx,.wx */
461 case MFPR:
462 case COM:
463 case NEG:
464/* .rx,.wx or .rx,.rx,.wx */
465 case ADD:
466 case SUB:
467 case BIC:
468 case BIS:
469 case XOR:
470 case MUL:
471 case DIV:
472 case ASH:
473 case MOVZ:
474/* .rx,.rx,.rx,.wx */
475 case EXTV:
476 case EXTZV:
477 case INSV:
478 splitrand(p);
479 repladdr(p);
480 dest(lastrand,p->subop);
481 if (p->op==INSV) ccloc[0]=0;
482 break;
483
484/* .mx or .wx */
485 case CLR:
486 case INC:
487 case DEC:
488 splitrand(p);
489 dest(lastrand,p->subop);
490 if (p->op==CLR)
491 if ((r = isreg(regs[RT1])) >= 0)
492 savereg(r, "$0", p->subop);
493 else
494 setcon("$0", regs[RT1], p->subop);
495 break;
496
497/* .rx */
498 case TST:
499 case PUSH:
500 splitrand(p);
501 lastrand=regs[RT1+1]; /* fool repladdr into doing 1 operand */
502 repladdr(p);
503 if (p->op==TST && equstr(lastrand=regs[RT1], ccloc+1)
504 && ((0xf&(ccloc[0]>>4))==p->subop || equtype(ccloc[0],p->subop))
505 &&!source(lastrand)) {
506 delnode(p); p = p->back; nrtst++; nchange++;
507 }
508 setcc(lastrand,p->subop);
509 break;
510
511/* .rx,.rx,.rx */
512 case PROBER:
513 case PROBEW:
514 case CASE:
515 case MOVC3:
516/* .rx,.rx */
517 case MTPR:
518 case CALLS:
519 case CMP:
520 case BIT:
521 splitrand(p);
522 /* fool repladdr into doing right number of operands */
9ad46604 523 if (p->op==CASE || p->op==PROBER || p->op==PROBEW) lastrand=regs[RT4];
c2a86b7c 524/* else if (p->op==CMPV || p->op==CMPZV) lastrand=regs[RT4+1]; */
9ad46604 525 else if (p->op==MOVC3) lastrand=regs[RT1];
f00d91fc
BJ		 526 else lastrand=regs[RT3];
527 repladdr(p);
528 if (p->op==CALLS || p->op==MOVC3) clearreg();
529 if (p->op==BIT) bitopt(p);
530 ccloc[0]=0; break;
531
532 case CBR:
533 if (p->subop>=JBC) {
534 splitrand(p);
535 if (p->subop<JBCC) lastrand=regs[RT3]; /* 2 operands can be optimized */
536 else lastrand=regs[RT2]; /* .mb destinations lose */
537 repladdr(p);
538 }
539 ccloc[0] = 0;
540 break;
541
542 case JBR:
543 redunbr(p);
544
545/* .wx,.bb */
546 case SOB:
547
548 default:
549 clearreg();
550 }
551 }
552}
553
554char *
555byondrd(p) register struct node *p; {
556/* return pointer to register which is "beyond last read/modify operand" */
557 if (OP2==(p->subop>>4)) return(regs[RT3]);
558 switch (p->op) {
559 case MFPR:
560 case JSB:
561 case PUSHA:
562 case TST: case INC: case DEC: case PUSH: return(regs[RT2]);
563 case MTPR:
564 case BIT: case CMP: case CALLS: return(regs[RT3]);
565 case PROBER: case PROBEW:
566 case CASE: case MOVC3: return(regs[RT4]);
567 }
568 return(lastrand);
569}
570
571struct node *
572bflow(p)
573register struct node *p;
574{
575 register char *cp1,*cp2,**preg; register int r;
576 int flow= -1;
577 struct node *olduse=0;
578 splitrand(p);
579 if (p->op!=PUSH && p->subop && 0<=(r=isreg(lastrand)) && r<NUSE && uses[r]==p->forw) {
580 if (equtype(p->subop,regs[r][0])
581 || ((p->op==CVT || p->op==MOVZ)
582 && 0xf&regs[r][0] && compat(0xf&(p->subop>>4),regs[r][0]))) {
583 register int r2;
584 if (regs[r][1]!=0) {/* send directly to destination */
585 if (p->op==INC || p->op==DEC) {
586 if (p->op==DEC) p->op=SUB; else p->op=ADD;
587 p->subop=(OP2<<4)+(p->subop&0xF); /* use 2 now, convert to 3 later */
588 p->pop=0;
589 cp1=lastrand; cp2=regs[RT2]; while (*cp2++= *cp1++); /* copy reg */
590 cp1=lastrand; *cp1++='$'; *cp1++='1'; *cp1=0;
591 }
592 cp1=regs[r]+1; cp2=lastrand;
593 if (OP2==(p->subop>>4)) {/* use 3 operand form of instruction */
594 p->pop=0;
595 p->subop += (OP3-OP2)<<4; lastrand=cp2=regs[RT3];
596 }
597 while (*cp2++= *cp1++);
598 if (p->op==MOVA && p->forw->op==PUSH) {
599 p->op=PUSHA; *regs[RT2]=0; p->pop=0;
600 } else if (p->op==MOV && p->forw->op==PUSH) {
601 p->op=PUSH ; *regs[RT2]=0; p->pop=0;
602 }
603 delnode(p->forw);
604 if (0<=(r2=isreg(lastrand)) && r2<NUSE) {
605 uses[r2]=uses[r]; uses[r]=0;
606 }
41feb04a 607 (void) redun3(p,0);
f00d91fc
BJ		 608 newcode(p); redunm++; flow=r;
609 } else if (p->op==MOV && p->forw->op!=EXTV && p->forw->op!=EXTZV) {
610 /* superfluous fetch */
611 int nmatch;
033bb901 612 char src[C2_ASIZE];
f00d91fc
BJ		 613 movit:
614 cp2=src; cp1=regs[RT1]; while (*cp2++= *cp1++);
615 splitrand(p->forw);
616 if (p->forw->op != INC && p->forw->op != DEC)
617 lastrand=byondrd(p->forw);
618 nmatch=0;
619 for (preg=regs+RT1;*preg!=lastrand;preg++)
620 if (r==isreg(*preg)) {
621 cp2= *preg; cp1=src; while (*cp2++= *cp1++); ++nmatch;
622 }
623 if (nmatch==1) {
624 if (OP2==(p->forw->subop>>4) && equstr(src,regs[RT2])) {
625 p->forw->pop=0;
626 p->forw->subop += (OP3-OP2)<<4; cp1=regs[RT3];
627 *cp1++='r'; *cp1++=r+'0'; *cp1=0;
628 }
629 delnode(p); p=p->forw;
630 if (0<=(r2=isreg(src)) && r2<NUSE) {
631 uses[r2]=uses[r]; uses[r]=0;
632 }
41feb04a 633 (void) redun3(p,0);
f00d91fc
BJ		 634 newcode(p); redunm++; flow=r;
635 } else splitrand(p);
636 }
637 } else if (p->op==MOV && (p->forw->op==CVT || p->forw->op==MOVZ)
638 && p->forw->subop&0xf /* if base or index, then forget it */
639 && compat(p->subop,p->forw->subop) && !source(cp1=regs[RT1])
640 && !indexa(cp1)) goto movit;
641 }
642 /* adjust 'lastrand' past any 'read' or 'modify' operands. */
643 lastrand=byondrd(p);
644 /* a 'write' clobbers the register. */
645 if (0<=(r=isreg(lastrand)) && r<NUSE
646 || OP2==(p->subop>>4) && 0<=(r=isreg(regs[RT2])) && r<NUSE && uses[r]==0) {
647 /* writing a dead register is useless, but watch side effects */
648 switch (p->op) {
35307d30 649 case ACB:
f00d91fc 650 case AOBLEQ: case AOBLSS: case SOBGTR: case SOBGEQ: break;
35307d30 651 default:
f00d91fc
BJ		 652 if (uses[r]==0) {/* no direct uses, check for use of condition codes */
653 register struct node *q=p;
654 while ((q=nonlab(q->forw))->combop==JBR) q=q->ref; /* cc unused, unchanged */
655 if (q->op!=CBR) {/* ... and destroyed */
656 preg=regs+RT1;
657 while (cp1= *preg++) {
658 if (cp1==lastrand) {redunm++; delnode(p); return(p->forw);}
659 if (source(cp1) || equstr(cp1,lastrand)) break;
660 }
661 }
662 }
663 flow=r;
664 }
665 }
41feb04a
RC		 666 if (0<=(r=flow)) {
667 olduse=uses[r];
668 uses[r]=0;
669 regs[r][0]=regs[r][1]=0;
670 }
f00d91fc
BJ		 671 /* these two are here, rather than in bmove(),
672 /* because I decided that it was better to go for 3-address code
673 /* (save time) rather than fancy jbxx (save 1 byte)
674 /* on sequences like bisl2 $64,r0; movl r0,foo
675 */
676 if (p->op==BIC) {p=bicopt(p); splitrand(p); lastrand=byondrd(p);}
41feb04a 677 if (p->op==BIS) {(void) bixprep(p,JBSS); lastrand=byondrd(p);}
f00d91fc
BJ		 678 /* now look for 'read' or 'modify' (read & write) uses */
679 preg=regs+RT1;
680 while (*(cp1= *preg++)) {
681 /* check for r */
682 if (lastrand!=cp1 && 0<=(r=isreg(cp1)) && r<NUSE && uses[r]==0) {
683 uses[r]=p; cp2=regs[r]; *cp2++=p->subop;
d1580951 684 if (p->op==ASH && preg==(regs+RT1+1)) cp2[-1]=BYTE; /* stupid DEC */
f00d91fc
BJ		 685 if (p->op==MOV || p->op==PUSH || p->op==CVT || p->op==MOVZ || p->op==COM || p->op==NEG) {
686 if (p->op==PUSH) cp1="-(sp)";
687 else {
688 cp1=regs[RT2];
689 if (0<=(r=isreg(cp1)) && r<NUSE && uses[r]==0)
690 uses[r]=olduse; /* reincarnation!! */
691 /* as in addl2 r0,r1; movl r1,r0; ret */
692 if (p->op!=MOV) cp1=0;
693 }
694 if (cp1) while (*cp2++= *cp1++);
d1580951
BJ		 695 else *cp2=0;
696 } else *cp2=0;
f00d91fc
BJ		 697 continue;
698 }
699 /* check for (r),(r)+,-(r),[r] */
700 do if (*cp1=='(' || *cp1=='[') {/* get register number */
701 char t;
702 cp2= ++cp1; while (*++cp1!=')' && *cp1!=']'); t= *cp1; *cp1=0;
703 if (0<=(r=isreg(cp2)) && r<NUSE && (uses[r]==0 || uses[r]==p)) {
704 uses[r]=p; regs[r][0]=(*--cp2=='[' ? OPX<<4 : OPB<<4);
705 }
706 *cp1=t;
707 } while (*++cp1);
708 }
709 /* pushax or movax possibility? */
710 cp1=regs[RT1];
711 if (*cp1++=='$' && isstatic(cp1) && natural(regs[RT1])) {
712 if (p->combop==T(MOV,LONG)) {
713 if (regs[RT1][1]=='L' && 0!=(p->labno=getnum(regs[RT1]+2))) {
714 cp1=p->code; while (*cp1++!=','); p->code= --cp1;
715 }
716 p->combop=T(MOVA,LONG); ++p->code; p->pop=0;
717 } else if (p->combop==T(PUSH,LONG)) {
718 p->combop=T(PUSHA,LONG); ++p->code; p->pop=0;
719 } else if ((p->combop&0xFFFF)==T(ADD,U(LONG,OP3))
720 && 0<=(r=isreg(regs[RT2]))) {
721 cp1=cp2=p->code; ++cp1;
722 do *cp2++= *cp1; while (*cp1++!=','); cp2[-1]='[';
723 do *cp2++= *cp1; while (*cp1++!=','); cp2[-1]=']';
724 if (!equstr(regs[RT3],"-(sp)")) p->combop=T(MOVA,BYTE);
725 else {p->combop=T(PUSHA,BYTE); *cp2=0;}
726 if (uses[r]==0) {uses[r]=p; regs[r][0]=OPX<<4;}
727 p->pop=0;
728 }
729 }
730 return(p);
731}
732
733ispow2(n) register long n; {/* -1 -> no; else -> log to base 2 */
734 register int log;
735 if (n==0 || n&(n-1)) return(-1); log=0;
736 for (;;) {n >>= 1; if (n==0) return(log); ++log; if (n== -1) return(log);}
737}
738
739bitopt(p) register struct node *p; {
740 /* change "bitx $<power_of_2>,a" followed by JEQ or JNE
741 /* into JBC or JBS. watch out for I/O registers. (?)
742 /* assumes that 'splitrand' has already been called.
743 */
744 register char *cp1,*cp2; int b;
745 cp1=regs[RT1]; cp2=regs[RT2];
746 if (*cp1++!='$' || !okio(cp2) || p->forw->op!=CBR || p->forw->subop&-2 ||
747 0>(b=ispow2(getnum(cp1))) ||
748 p->subop!=BYTE && (source(cp2) || indexa(cp2))) return;
749 if (b>=bitsize[p->subop]) {/* you dummy! */
750 if (source(cp2)) {/* side effect: auto increment or decrement */
751 p->pop=0;
752 p->op=TST; --cp1; while (*cp1++= *cp2++);
753 regs[RT2][0]=0; newcode(p);
754 } else delnode(p);
755 p = p->forw;
756 if (p->subop==JEQ) {p->combop=JBR; p->pop=0;}
757 else delnode(p);
758 nchange++; nbj++; return;
759 }
760 if (cp1=p->forw->code) {/* destination is not an internal label */
761 cp2=regs[RT3]; while (*cp2++= *cp1++);
762 }
763 if (b==0 && (p->subop==LONG || !indexa(regs[RT2]))) {/* JLB optimization, ala BLISS */
764 cp2=regs[RT1]; cp1=regs[RT2]; while (*cp2++= *cp1++);
765 cp2=regs[RT2]; cp1=regs[RT3]; while (*cp2++= *cp1++);
766 *(regs[RT3])=0; p->forw->subop += JLBC-JBC;
767 p->forw->pop=0;
768 } else {
769 cp1=regs[RT1]+1;
770 if (b>9) *cp1++= b/10 +'0'; *cp1++= b%10 +'0'; *cp1=0; /* $<bit_number> */
771 }
772 nbj++; newcode(p); p->combop = p->forw->combop+((JBC-JEQ)<<8);
773 p->labno = p->forw->labno; delnode(p->forw);
774 p->pop=0;
775}
776
777isfield(n) register long n; {/* -1 -> no; else -> position of low bit */
41feb04a 778 register int p; register long t;
f00d91fc 779 t= ((n-1)|n) +1;
eea63b82 780 if (n!=0 && (0==t || 0<=ispow2(t))) {
41feb04a 781 p=0; while(!(n&1)) {n >>= 1; ++p;} return(p);
f00d91fc
BJ		 782 } else return(-1);
783}
784
785bixprep(p,bix) register struct node *p; {
786/* initial setup, single-bit checking for bisopt, bicopt.
787/* return: 0->don't bother any more; 1->worthwhile trying
788*/
789 register char *cp1,*cp2;
790 splitrand(p); cp1=regs[RT1]; cp2=regs[RT2];
791 if (*cp1++!='$' || 0>(pos=isfield(f=getnum(cp1)))
792 || !okio(cp2) || indexa(cp2) || source(cp2) || !okio(lastrand)) return(0);
793 f |= f-1; if (++f==0) siz=32-pos; else siz=ispow2(f)-pos;
794 if (siz==1 && pos>5 && (p->subop>>4)==OP2 && (p->subop&0xF)!=BYTE
795 && pos<bitsize[p->subop&0xF]) {
796 p->ref = insertl(p->forw); p->combop = CBR | (bix<<8);
797 p->pop=0;
798 p->labno = p->ref->labno;
799 if (pos>9) {*cp1++= pos/10 +'0'; pos %= 10;}
800 *cp1++=pos+'0'; *cp1=0; newcode(p); nbj++; return(0);
801 }
802 return(1);
803}
804
805
806struct node *
807bicopt(p) register struct node *p; {
808/* use field operations or MOVZ if possible. done as part of 'bflow'.
809*/
810 register char *cp1,*cp2; int r;
3b60efae 811 char src[C2_ASIZE];
41feb04a 812 char lhssiz, sop;
f00d91fc
BJ		 813 if (!bixprep(p,JBCC)) return(p);
814 if (f==0) {/* the BIC isolates low order bits */
815 siz=pos; pos=0;
816 if ((p->subop&0xF)==LONG && *(regs[RT2])!='$') {/* result of EXTZV is long */
817 /* save source of BICL in 'src' */
818 cp1=regs[RT2]; cp2=src; while (*cp2++= *cp1++);
819 if (p->back->op==ASH) {/* try for more */
820 splitrand(p->back); cp1=regs[RT1]; cp2=regs[RT3];
821 if (*cp1++=='$' && *(regs[RT2])!='$' && !indexa(regs[RT2])
822 && 0>(f=getnum(cp1)) && equstr(src,cp2)
eea63b82
RC		 823 && 0<=(r=isreg(cp2)) && r<NUSE
824 && siz-f <= 32) { /* a good ASH */
f00d91fc
BJ		 825 pos -= f; cp1=regs[RT2]; cp2=src; while (*cp2++= *cp1++);
826 delnode(p->back);
827 }
828 }
49c27f9c
RC		 829 /*
830 * 'pos', 'siz' known; find out the size of the
831 * left-hand operand of what the bicl will turn into.
832 */
833 if (pos==0 && siz==16)
834 lhssiz = WORD; /* movzwl */
835 else
836 lhssiz = BYTE; /* movzbl or extzvl */
f00d91fc
BJ		 837 if (p->back->op==CVT || p->back->op==MOVZ) {/* greedy, aren't we? */
838 splitrand(p->back); cp1=regs[RT1]; cp2=regs[RT2];
49c27f9c
RC		 839 /*
840 * If indexa(cp1) || autoid(cp1), the fold may
841 * still be OK if the CVT/MOVZ has the same
842 * size operand on its left size as what we
843 * will turn the bicl into.
844 * However, if the CVT is from a float or
845 * double, forget it!
846 */
41feb04a 847 sop = p->back->subop&0xF; /* type of LHS of CVT/MOVZ */
49c27f9c 848 if (equstr(src,cp2) && okio(cp1)
41feb04a
RC		 849 && sop != FFLOAT && sop != DFLOAT
850 && sop != GFLOAT && sop != HFLOAT
851 && ((!indexa(cp1) && !autoid(cp1)) || lhssiz == sop)
f00d91fc 852 && 0<=(r=isreg(cp2)) && r<NUSE
41feb04a 853 && bitsize[sop]>=(pos+siz)
f00d91fc
BJ		 854 && bitsize[p->back->subop>>4]>=(pos+siz)) {/* good CVT */
855 cp1=regs[RT1]; cp2=src; while (*cp2++= *cp1++);
856 delnode(p->back);
857 }
858 }
859 /* 'pos', 'siz' known; source of field is in 'src' */
860 splitrand(p); /* retrieve destination of BICL */
49c27f9c
RC		 861 if ((siz==8 || siz==16) && pos==0) {
862 p->combop = T(MOVZ,U(lhssiz,LONG));
f00d91fc
BJ		 863 sprintf(line,"%s,%s",src,lastrand);
864 } else {
865 p->combop = T(EXTZV,LONG);
866 sprintf(line,"$%d,$%d,%s,%s",pos,siz,src,lastrand);
867 }
868 p->pop=0;
869 p->code = copy(line); nfield++; return(p);
870 }/* end EXTZV possibility */
871 }/* end low order bits */
872/* unfortunately, INSV clears the condition codes, thus cannot be used */
873/* else {/* see if BICL2 of positive field should be INSV $0 */
874/* if (p->subop==(LONG | (OP2<<4)) && 6<=(pos+siz)) {
875/* p->combop = INSV;
876/* sprintf(line,"$0,$%d,$%d,%s",pos,siz,lastrand);
877/* p->code = copy(line); nfield++; return(p);
878/* }
879/* }
880*/
881 return(p);
882}
883
884jumpsw()
885{
886 register struct node *p, *p1;
41feb04a
RC		 887 register struct node *tp;
888 long tl;
889 char *tcp;
890 int ti;
f00d91fc
BJ		 891 int nj;
892
41feb04a 893 ti = 0;
f00d91fc
BJ		 894 nj = 0;
895 for (p=first.forw; p!=0; p = p->forw)
41feb04a 896 p->seq = ++ti;
f00d91fc
BJ		 897 for (p=first.forw; p!=0; p = p1) {
898 p1 = p->forw;
899 if (p->op == CBR && p1->op==JBR && p->ref && p1->ref
900 && abs(p->seq - p->ref->seq) > abs(p1->seq - p1->ref->seq)) {
901 if (p->ref==p1->ref)
902 continue;
903 p->subop = revbr[p->subop];
904 p->pop=0;
41feb04a 905 tp = p1->ref;
f00d91fc 906 p1->ref = p->ref;
41feb04a
RC		 907 p->ref = tp;
908 tl = p1->labno;
f00d91fc 909 p1->labno = p->labno;
41feb04a 910 p->labno = tl;
f00d91fc
BJ		 911#ifdef COPYCODE
912 if (p->labno == 0) {
41feb04a
RC		 913 tcp = p1->code;
914 p1->code = p->code;
915 p->code = tcp;
f00d91fc
BJ		 916 }
917#endif
918 nrevbr++;
919 nj++;
920 }
921 }
922 return(nj);
923}
924
925addsob()
926{
927 register struct node *p, *p1, *p2, *p3;
928
929 for (p = &first; (p1 = p->forw)!=0; p = p1) {
930 if (p->combop==T(DEC,LONG) && p1->op==CBR) {
3b60efae 931 if (abs(p->seq - p1->ref->seq) > 8) continue;
f00d91fc
BJ		 932 if (p1->subop==JGE || p1->subop==JGT) {
933 if (p1->subop==JGE) p->combop=SOBGEQ; else p->combop=SOBGTR;
934 p->pop=0;
935 p->labno = p1->labno; delnode(p1); nsob++;
936 }
937 } else if (p->combop==T(INC,LONG)) {
938 if (p1->op==LABEL && p1->refc==1 && p1->forw->combop==T(CMP,LONG)
939 && (p2=p1->forw->forw)->combop==T(CBR,JLE)
940 && (p3=p2->ref->back)->combop==JBR && p3->ref==p1
941 && p3->forw->op==LABEL && p3->forw==p2->ref) {
942 /* change INC LAB: CMP to LAB: INC CMP */
943 p->back->forw=p1; p1->back=p->back;
944 p->forw=p1->forw; p1->forw->back=p;
945 p->back=p1; p1->forw=p;
946 p1=p->forw;
947 /* adjust beginning value by 1 */
948 p2=alloc(sizeof first); p2->combop=T(DEC,LONG);
949 p2->pop=0;
950 p2->forw=p3; p2->back=p3->back; p3->back->forw=p2;
951 p3->back=p2; p2->code=p->code; p2->labno=0;
952 }
953 if (p1->combop==T(CMP,LONG) && (p2=p1->forw)->op==CBR) {
954 register char *cp1,*cp2;
955 splitrand(p1); if (!equstr(p->code,regs[RT1])) continue;
3b60efae 956 if (abs(p->seq - p2->ref->seq)>8) {/* outside byte displ range */
f00d91fc
BJ		 957 if (p2->subop!=JLE) continue;
958 p->combop=T(ACB,LONG);
959 cp2=regs[RT1]; cp1=regs[RT2]; while (*cp2++= *cp1++); /* limit */
960 cp2=regs[RT2]; cp1="$1"; while (*cp2++= *cp1++); /* increment */
961 cp2=regs[RT3]; cp1=p->code; while (*cp2++= *cp1++); /* index */
962 p->pop=0; newcode(p);
963 p->labno = p2->labno; delnode(p2); delnode(p1); nsob++;
964 } else if (p2->subop==JLE || p2->subop==JLT) {
965 if (p2->subop==JLE) p->combop=AOBLEQ; else p->combop=AOBLSS;
966 cp2=regs[RT1]; cp1=regs[RT2]; while (*cp2++= *cp1++); /* limit */
967 cp2=regs[RT2]; cp1=p->code; while (*cp2++= *cp1++); /* index */
968 p->pop=0; newcode(p);
969 p->labno = p2->labno; delnode(p2); delnode(p1); nsob++;
970 }
971 }
972 }
973 }
974}
975
f00d91fc
BJ		 976equop(p1, p2)
977register struct node *p1;
978struct node *p2;
979{
980 register char *cp1, *cp2;
981
982 if (p1->combop != p2->combop)
983 return(0);
984 if (p1->op>0 && p1->op<MOV)
985 return(0);
41feb04a
RC		 986 switch (p1->combop) {
987 case EROU: case JSW: case TEXT: case DATA:
988 case BSS: case ALIGN: case WGEN: case END:
989 /*
990 * Consider all pseudo-ops to be unique.
991 */
992 return(0);
993 }
f00d91fc
BJ		 994 if (p1->op==MOVA && p1->labno!=p2->labno) return(0);
995 cp1 = p1->code;
996 cp2 = p2->code;
997 if (cp1==0 && cp2==0)
998 return(1);
999 if (cp1==0 || cp2==0)
1000 return(0);
1001 while (*cp1 == *cp2++)
1002 if (*cp1++ == 0)
1003 return(1);
1004 return(0);
1005}
1006
41feb04a 1007#ifndef delnode
f00d91fc
BJ		 1008delnode(p) register struct node *p; {
1009 p->back->forw = p->forw;
1010 p->forw->back = p->back;
1011}
41feb04a 1012#endif
f00d91fc 1013
41feb04a 1014#ifndef decref
f00d91fc
BJ		 1015decref(p)
1016register struct node *p;
1017{
1018 if (p && --p->refc <= 0) {
1019 nrlab++;
1020 delnode(p);
1021 }
1022}
41feb04a 1023#endif
f00d91fc
BJ		 1024
1025struct node *
1026nonlab(ap)
1027struct node *ap;
1028{
1029 register struct node *p;
1030
1031 p = ap;
1032 while (p && p->op==LABEL)
1033 p = p->forw;
1034 return(p);
1035}
1036
1037clearuse() {
1038 register struct node **i;
1039 for (i=uses+NUSE; i>uses;) *--i=0;
1040}
1041
1042clearreg() {
41feb04a
RC		 1043 register char **i;
1044 for (i=regs; i<regs+NREG; ++i) {
1045 **i = 0;
1046 *(*i+1) = 0;
1047 }
1048 conloc[0] = 0;
1049 ccloc[0] = 0;
f00d91fc
BJ		 1050}
1051
1052savereg(ai, s, type)
1053register char *s;
1054{
1055 register char *p, *sp;
1056
1057 sp = p = regs[ai];
1058 if (source(s)) /* side effects in addressing */
1059 return;
1060 /* if any indexing, must be parameter or local */
1061 /* indirection (as in "*-4(fp)") is ok, however */
1062 *p++ = type;
1063 while (*p++ = *s)
1064 if (*s=='[' || *s++=='(' && *s!='a' && *s!='f') {*sp = 0; return;}
1065}
1066
1067dest(s,type)
1068register char *s;
1069{
1070 register int i;
1071
41feb04a 1072 (void) source(s); /* handle addressing side effects */
6b028d93
RC		 1073 if (!natural(s)) {
1074 /* wild store, everything except constants vanishes */
1075 for (i=NREG; --i>=0;)
41feb04a
RC		 1076 if (regs[i][1] != '$')
1077 regs[i][0] = regs[i][1] = 0;
6b028d93
RC		 1078 conloc[0] = 0; ccloc[0] = 0;
1079 return;
1080 }
f00d91fc 1081 if ((i = isreg(s)) >= 0) {
41feb04a
RC		 1082 /* if register destination, that reg is a goner */
1083 regs[i][0] = regs[i][1] = 0;
0594fe30
BJ		 1084 switch(type & 0xF){
1085 case DFLOAT: /* clobber two at once */
1086 /*FALLTHROUGH*/
1087 case GFLOAT:
41feb04a 1088 regs[i+1][0] = regs[i+1][1] = 0;
0594fe30
BJ		 1089 break;
1090 case HFLOAT: /* clobber four at once */
41feb04a
RC		 1091 regs[i+1][0] = regs[i+1][1] = 0;
1092 regs[i+2][0] = regs[i+2][1] = 0;
1093 regs[i+3][0] = regs[i+3][1] = 0;
0594fe30
BJ		 1094 break;
1095 }
1096 switch((type>>4)&0xF){
1097 case DFLOAT: /* clobber two at once */
1098 /*FALLTHROUGH*/
1099 case GFLOAT:
41feb04a 1100 regs[i+1][0] = regs[i+1][1] = 0;
0594fe30
BJ		 1101 break;
1102 case HFLOAT: /* clobber four at once */
41feb04a
RC		 1103 regs[i+1][0] = regs[i+1][1] = 0;
1104 regs[i+2][0] = regs[i+2][1] = 0;
1105 regs[i+3][0] = regs[i+3][1] = 0;
0594fe30
BJ		 1106 break;
1107 }
f00d91fc
BJ		 1108 }
1109 for (i=NREG; --i>=0;)
1110 if (regs[i][1]=='*' && equstr(s, regs[i]+2))
41feb04a 1111 regs[i][0] = regs[i][1] = 0; /* previous indirection through destination is invalid */
f00d91fc 1112 while ((i = findrand(s,0)) >= 0) /* previous values of destination are invalid */
41feb04a 1113 regs[i][0] = regs[i][1] = 0;
6b028d93
RC		 1114 if (*conloc && equstr(conloc, s))
1115 conloc[0] = 0;
1116 setcc(s, type); /* natural destinations set condition codes */
f00d91fc
BJ		 1117}
1118
f00d91fc 1119/* separate operands at commas, set up 'regs' and 'lastrand' */
6b028d93
RC		 1120splitrand(p) struct node *p; {
1121 register char *p1, *p2;
1122 register char **preg;
1123
1124 preg = regs+RT1;
1125 if (p1 = p->code)
1126 while (*p1) {
1127 lastrand = p2 = *preg++;
1128 while (*p1)
1129 if (',' == (*p2++ = *p1++)) {
1130 --p2;
1131 break;
1132 }
1133 *p2 = 0;
1134 }
1135 while (preg < (regs+RT1+5))
1136 *(*preg++) = 0;
f00d91fc
BJ		 1137}
1138
1139compat(have, want) {
1140register int hsrc, hdst;
1141if (0==(want &= 0xF)) return(1); /* anything satisfies a wildcard want */
1142hsrc=have&0xF; if (0==(hdst=((have>>4)&0xF)) || hdst>=OP2) hdst=hsrc;
0594fe30
BJ		 1143if (want>=FFLOAT) return(hdst==want && hsrc==want);
1144 /* FLOAT, DFLOAT not compat: rounding */
1145return(hsrc>=want && hdst>=want && hdst<FFLOAT);
f00d91fc
BJ		 1146}
1147
1148equtype(t1,t2) {return(compat(t1,t2) && compat(t2,t1));}
1149
1150findrand(as, type)
1151char *as;
1152{
1153 register char **i;
1154 for (i = regs+NREG; --i>=regs;) {
1155 if (**i && equstr(*i+1, as) && compat(**i,type))
1156 return(i-regs);
1157 }
1158 return(-1);
1159}
1160
1161isreg(s)
1162register char *s;
1163{
1164 if (*s++!='r' || !isdigit(*s++)) return(-1);
1165 if (*s==0) return(*--s-'0');
1166 if (*(s-1)=='1' && isdigit(*s++) && *s==0) return(10+*--s-'0');
1167 return(-1);
1168}
1169
1170check()
1171{
1172 register struct node *p, *lp;
1173
1174 lp = &first;
1175 for (p=first.forw; p!=0; p = p->forw) {
41feb04a
RC		 1176 if (p->back != lp) {
1177 fprintf(stderr, "c2: failed internal consistency check -- help!\n");
1178 exit(-1);
1179 }
f00d91fc
BJ		 1180 lp = p;
1181 }
1182}
1183
1184source(ap)
1185char *ap;
1186{
1187 register char *p1, *p2;
1188
1189 p1 = ap;
1190 p2 = p1;
1191 if (*p1==0)
1192 return(0);
1193 while (*p2++ && *(p2-1)!='[');
1194 if (*p1=='-' && *(p1+1)=='('
1195 || *p1=='*' && *(p1+1)=='-' && *(p1+2)=='('
1196 || *(p2-2)=='+') {
1197 while (*p1 && *p1++!='r');
1198 if (isdigit(*p1++))
41feb04a
RC		 1199 if (isdigit(*p1))
1200 regs[10+*p1-'0'][0] = regs[10+*p1-'0'][1] = 0;
1201 else {
1202 --p1;
1203 regs[*p1-'0'][0] = regs[*p1-'0'][1] = 0;
1204 }
f00d91fc
BJ		 1205 return(1);
1206 }
1207 return(0);
1208}
1209
1210newcode(p) struct node *p; {
1211 register char *p1,*p2,**preg;
1212 preg=regs+RT1; p2=line;
1213 while (*(p1= *preg++)) {while (*p2++= *p1++); *(p2-1)=',';}
1214 *--p2=0;
1215 p->code=copy(line);
1216}
1217
1218repladdr(p)
1219struct node *p;
1220{
1221 register r;
41feb04a 1222 register char *p1;
f00d91fc
BJ		 1223 char **preg; int nrepl;
1224
1225 preg=regs+RT1; nrepl=0;
1226 while (lastrand!=(p1= *preg++))
1227 if (!source(p1) && 0<=(r=findrand(p1,p->subop))) {
1228 *p1++='r'; if (r>9) {*p1++='1'; r -= 10;} *p1++=r+'0'; *p1=0;
1229 nrepl++; nsaddr++;
1230 }
1231 if (nrepl) newcode(p);
1232}
1233
1234/* movedat()
1235/* {
1236/* register struct node *p1, *p2;
1237/* struct node *p3;
1238/* register seg;
1239/* struct node data;
1240/* struct node *datp;
1241/*
1242/* if (first.forw == 0)
1243/* return;
1244/* datp = &data;
1245/* for (p1 = first.forw; p1!=0; p1 = p1->forw) {
1246/* if (p1->op == DATA) {
1247/* p2 = p1->forw;
1248/* while (p2 && p2->op!=TEXT)
1249/* p2 = p2->forw;
1250/* if (p2==0)
1251/* break;
1252/* p3 = p1->back;
1253/* p1->back->forw = p2->forw;
1254/* p2->forw->back = p3;
1255/* p2->forw = 0;
1256/* datp->forw = p1;
1257/* p1->back = datp;
1258/* p1 = p3;
1259/* datp = p2;
1260/* }
1261/* }
1262/* if (data.forw) {
1263/* datp->forw = first.forw;
1264/* first.forw->back = datp;
1265/* data.forw->back = &first;
1266/* first.forw = data.forw;
1267/* }
1268/* seg = -1;
1269/* for (p1 = first.forw; p1!=0; p1 = p1->forw) {
1270/* if (p1->op==TEXT||p1->op==DATA||p1->op==BSS) {
1271/* if (p1->op == seg || p1->forw&&p1->forw->op==seg) {
1272/* p1->back->forw = p1->forw;
1273/* p1->forw->back = p1->back;
1274/* p1 = p1->back;
1275/* continue;
1276/* }
1277/* seg = p1->op;
1278/* }
1279/* }
1280/* }
1281*/
1282
1283redunbr(p)
1284register struct node *p;
1285{
1286 register struct node *p1;
1287 register char *ap1;
1288 char *ap2;
1289
1290 if ((p1 = p->ref) == 0)
1291 return;
1292 p1 = nonlab(p1);
1293 if (p1->op==TST) {
1294 splitrand(p1);
1295 savereg(RT2, "$0", p1->subop);
1296 } else if (p1->op==CMP)
1297 splitrand(p1);
1298 else
1299 return;
1300 if (p1->forw->op==CBR) {
1301 ap1 = findcon(RT1, p1->subop);
1302 ap2 = findcon(RT2, p1->subop);
1303 p1 = p1->forw;
1304 if (compare(p1->subop, ap1, ap2)) {
1305 nredunj++;
1306 nchange++;
1307 decref(p->ref);
1308 p->ref = p1->ref;
1309 p->labno = p1->labno;
1310#ifdef COPYCODE
1311 if (p->labno == 0)
1312 p->code = p1->code;
f00d91fc 1313#endif
6b028d93 1314 if (p->ref)
f00d91fc
BJ		 1315 p->ref->refc++;
1316 }
1317 } else if (p1->op==TST && equstr(regs[RT1],ccloc+1) &&
1318 equtype(ccloc[0],p1->subop)) {
1319 p1=insertl(p1->forw); decref(p->ref); p->ref=p1;
1320 nrtst++; nchange++;
1321 }
1322}
1323
1324char *
1325findcon(i, type)
1326{
1327 register char *p;
1328 register r;
1329
1330 p = regs[i];
1331 if (*p=='$')
1332 return(p);
1333 if ((r = isreg(p)) >= 0 && compat(regs[r][0],type))
1334 return(regs[r]+1);
1335 if (equstr(p, conloc))
1336 return(conval+1);
1337 return(p);
1338}
1339
41feb04a 1340compare(opc, acp1, acp2)
f00d91fc
BJ		 1341char *acp1, *acp2;
1342{
1343 register char *cp1, *cp2;
1344 register n1;
1345 int n2; int sign;
1346
1347 cp1 = acp1;
1348 cp2 = acp2;
1349 if (*cp1++ != '$' || *cp2++ != '$')
1350 return(0);
1351 n1 = 0; sign=1; if (*cp2=='-') {++cp2; sign= -1;}
1352 while (isdigit(*cp2)) {n1 *= 10; n1 += (*cp2++ - '0')*sign;}
1353 n2 = n1;
1354 n1 = 0; sign=1; if (*cp1=='-') {++cp1; sign= -1;}
1355 while (isdigit(*cp1)) {n1 *= 10; n1 += (*cp1++ - '0')*sign;}
1356 if (*cp1=='+')
1357 cp1++;
1358 if (*cp2=='+')
1359 cp2++;
1360 do {
1361 if (*cp1++ != *cp2)
1362 return(0);
1363 } while (*cp2++);
41feb04a 1364 switch(opc) {
f00d91fc
BJ		 1365
1366 case JEQ:
41feb04a 1367 return(n1 == n2);
f00d91fc 1368 case JNE:
41feb04a 1369 return(n1 != n2);
f00d91fc 1370 case JLE:
41feb04a 1371 return(n1 <= n2);
f00d91fc 1372 case JGE:
41feb04a 1373 return(n1 >= n2);
f00d91fc 1374 case JLT:
41feb04a 1375 return(n1 < n2);
f00d91fc 1376 case JGT:
41feb04a 1377 return(n1 > n2);
f00d91fc 1378 case JLO:
41feb04a 1379 return((unsigned) n1 < (unsigned) n2);
f00d91fc 1380 case JHI:
41feb04a 1381 return((unsigned) n1 > (unsigned) n2);
f00d91fc 1382 case JLOS:
41feb04a 1383 return((unsigned) n1 <= (unsigned) n2);
f00d91fc 1384 case JHIS:
41feb04a 1385 return((unsigned) n1 >= (unsigned) n2);
f00d91fc
BJ		 1386 }
1387 return(0);
1388}
1389
1390setcon(cv, cl, type)
1391register char *cv, *cl;
1392{
1393 register char *p;
1394
1395 if (*cv != '$')
1396 return;
1397 if (!natural(cl))
1398 return;
1399 p = conloc;
1400 while (*p++ = *cl++);
1401 p = conval;
1402 *p++ = type;
1403 while (*p++ = *cv++);
1404}
1405
1406equstr(p1, p2)
1407register char *p1, *p2;
1408{
1409 do {
1410 if (*p1++ != *p2)
1411 return(0);
1412 } while (*p2++);
1413 return(1);
1414}
1415
1416setcc(ap,type)
1417char *ap;
1418{
1419 register char *p, *p1;
1420
1421 p = ap;
1422 if (!natural(p)) {
1423 ccloc[0] = 0;
1424 return;
1425 }
1426 p1 = ccloc;
1427 *p1++ = type;
1428 while (*p1++ = *p++);
1429}
1430
1431okio(p) register char *p; {/* 0->probable I/O space address; 1->not */
1432 if (ioflag && (!natural(p) || 0>getnum(p))) return(0);
1433 return(1);
1434}
1435
1436indexa(p) register char *p; {/* 1-> uses [r] addressing mode; 0->doesn't */
1437 while (*p) if (*p++=='[') return(1);
1438 return(0);
1439}
1440
1441natural(p)
1442register char *p;
1443{/* 1->simple local, parameter, global, or register; 0->otherwise */
6b028d93 1444 if (*p=='*' || *p=='(' || *p=='-'&&p[1]=='(' || *p=='$'&&getnum(p+1))
f00d91fc
BJ		 1445 return(0);
1446 while (*p++);
1447 p--;
6b028d93 1448 if (*--p=='+' || *p==']' || *p==')' && p[-2]!='a' && p[-2]!='f')
f00d91fc
BJ		 1449 return(0);
1450 return(1);
1451}
1452
1453/*
1454** Tell if an argument is most likely static.
1455*/
1456
1457isstatic(cp)
1458register char *cp;
1459{
1460 if (*cp == '_' || *cp == 'L' || (*cp++ == 'v' && *cp == '.'))
1461 return (1);
1462 return (0);
1463}
49c27f9c
RC		 1464
1465autoid(p) register char *p; {/* 1-> uses autoincrement/autodecrement; 0->doesn't */
1466 if (*p == '-' && *(p+1) == '(') return(1);
1467 while (*p) p++;
1468 if (*--p == '+' && *--p == ')') return(1);
1469 return(0);
1470 }
Continuous source code history from original PDP-7 UNIX to FreeBSD 2, the first fully unencumbered FreeBSD release.