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1.1 root 1: #ifndef lint
2: static char sccsid[] = "@(#)c21.c 4.19 4/27/86";
3: #endif
4: /* char C21[] = {"@(#)c21.c 1.83 80/10/16 21:18:22 JFR"}; /* sccs ident */
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
15: int ioflag;
16: int biti[NUSE] = {1,2,4,8,16,32};
17: int bitsize[] = { /* index by type codes */
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 */
32: };
33: int pos,siz; long f; /* for bit field communication */
34: struct node *uses[NUSE]; /* for backwards flow analysis */
35: char *lastrand; /* last operand of instruction */
36: struct node *bflow();
37: struct node *bicopt();
38: char *findcon();
39: char *strcpy();
40:
41: redun3(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:
56: bmove() {
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++)=='$' && *cp1++=='0' && *cp1++==',' &&
70: !source(cp1)) {/* a no-op unless MUL or DIV */
71: if (p->op==MUL) {p->op=MOV; p->subop&=0xF; p->pop=0;}
72: else if (p->op==DIV) fprintf(stderr,"c2: zero divide\n");
73: else {delnode(p); redunm++; continue;}
74: }
75: if (OP3==r && 0!=redun3(p,1)) {newcode(p); redunm++;}
76: switch (p->op) {
77: case LABEL: case DLABEL:
78: for (r=NUSE; --r>=0;)
79: if (uses[r]) p->ref=(struct node *) (((int)p->ref)|biti[r]);
80: break;
81: case CALLS:
82: clearuse(); goto std;
83: case 0:
84: /*
85: * Be conservative -- if we don't know what it is, then we
86: * assume that it can set anything.
87: */
88: for ( r = 0; r < NUSE; ++r )
89: uses[r] = p;
90: break;
91: case SUB:
92: if ((p->subop&0xF)!=LONG) goto std; cp1=p->code;
93: if (*cp1++!='$') goto std; splitrand(p);
94: if (equstr(regs[RT2],"fp") && !indexa(regs[RT1])) {/* address comp. */
95: char buf[C2_ASIZE]; cp2=buf; *cp2++='-';
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 $_foo,r0 \ movab _foo[r0],bar
110: ** movl r0,bar /
111: */
112: register struct node *pnext = p->forw;
113: char buf[C2_ASIZE];
114:
115: if (pnext->op == MOV && pnext->subop == LONG)
116: {
117: cp1 = ®s[RT1][1]; cp2 = &buf[0];
118: while (*cp2++ = *cp1++) ; cp2--;
119: splitrand(pnext);
120: if (r == isreg(regs[RT1]))
121: {
122: delnode(p); p = pnext;
123: p->op = MOVA; p->subop = BYTE;
124: p->pop = 0;
125: cp1 = regs[RT1]; *cp2++ = '[';
126: while (*cp2++ = *cp1++) ; cp2--;
127: *cp2++ = ']'; *cp2++ = ',';
128: cp1 = regs[RT2];
129: while (*cp2++ = *cp1++) ;
130: p->code = copy(buf);
131: }
132: }
133: }
134: else
135: if (equstr(regs[RT2],"fp") && !indexa(regs[RT1])) {/* address comp. */
136: cp2=cp1-1; cp1=regs[RT1]+1; while (*cp2++= *cp1++); --cp2;
137: cp1="(fp)"; while (*cp2++= *cp1++); *--cp2=',';
138: p->combop=T(MOVA,LONG); p->pop=0;
139: } else if (*cp1++=='-' && 0<=(r=getnum(cp1))) {
140: p->op=SUB; p->pop=0; *--cp1='$'; 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(®s[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(®s[RT1][1])) < 1 || shcnt > 3) goto std;
212: if ((shfrom = isreg(regs[RT2])) >= 0)
213: regfrom = copy(regs[RT2]);
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++);
242: *--cp2 = ']';
243: *++cp2 = '\0';
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: goto std;
263: }
264: ashadd:
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
289: ** extv $n*16,$16,A,B > cvtwl 2n+A,B
290: ** extzv $n*8,$8,A,B > movzbl n+A,B
291: ** extzv $n*16,$16,A,B > movzwl 2n+A,B
292: */
293: register struct node *pf; /* forward node */
294: register struct node *pn; /* next node (after pf) */
295: int flen; /* field length */
296:
297: splitrand(p);
298: if (regs[RT2][0] != '$') goto std;
299: if ((flen = getnum(®s[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] != '$') goto std;
327: if ((boff = getnum(®s[RT1][1])) < 0) goto std;
328: coff = boff / flen;
329: if (coff && (isreg(regs[RT3]) >= 0)) goto std;
330: if (boff < 0 || (boff % flen) != 0) goto std;
331: p->op = (p->op == EXTV) ? CVT : MOVZ;
332: p->subop = U((flen == 8 ? BYTE : WORD), LONG);
333: if (coff == 0)
334: strcpy(regs[RT1], regs[RT3]);
335: else
336: sprintf(regs[RT1], "%d%s%s",
337: (flen == 8 ? coff : 2*coff),
338: (regs[RT3][0] == '(' ? "" : "+"),
339: regs[RT3]);
340: strcpy(regs[RT2], regs[RT4]);
341: regs[RT3][0] = '\0'; regs[RT4][0] = '\0';
342: p->pop = 0; newcode(p);
343: }
344: nchange++;
345: goto std;
346: }
347:
348: case CMP:
349: {
350: /* comparison to -63 to -1:
351: ** cmpl r0,$-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(®s[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 = ®s[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:
415: rmove()
416: {
417: register struct node *p;
418: register int r;
419: int r1;
420:
421: clearreg();
422: for (p=first.forw; p!=0; p = p->forw) {
423: if (debug) {
424: if (*conloc) {
425: r1=conval[0];
426: printf("Con %s = %d%d %s\n", conloc, r1&0xF, r1>>4, conval+1);
427: }
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: }
448: mov:
449: repladdr(p);
450: r = isreg(regs[RT1]);
451: r1 = isreg(regs[RT2]);
452: dest(regs[RT2],p->subop);
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);
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 */
523: if (p->op==CASE || p->op==PROBER || p->op==PROBEW) lastrand=regs[RT4];
524: /* else if (p->op==CMPV || p->op==CMPZV) lastrand=regs[RT4+1]; */
525: else if (p->op==MOVC3) lastrand=regs[RT1];
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:
554: char *
555: byondrd(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:
571: struct node *
572: bflow(p)
573: register 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®s[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: }
607: (void) redun3(p,0);
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;
612: char src[C2_ASIZE];
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: }
633: (void) redun3(p,0);
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) {
649: case ACB:
650: case AOBLEQ: case AOBLSS: case SOBGTR: case SOBGEQ: break;
651: default:
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: }
666: if (0<=(r=flow)) {
667: olduse=uses[r];
668: uses[r]=0;
669: regs[r][0]=regs[r][1]=0;
670: }
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 $64,r0; movl r0,foo
675: */
676: if (p->op==BIC) {p=bicopt(p); splitrand(p); lastrand=byondrd(p);}
677: if (p->op==BIS) {(void) bixprep(p,JBSS); lastrand=byondrd(p);}
678: /* now look for 'read' or 'modify' (read & write) uses */
679: preg=regs+RT1;
680: while (*(cp1= *preg++)) {
681: /* check for r */
682: if (lastrand!=cp1 && 0<=(r=isreg(cp1)) && r<NUSE && uses[r]==0) {
683: uses[r]=p; cp2=regs[r]; *cp2++=p->subop;
684: if (p->op==ASH && preg==(regs+RT1+1)) cp2[-1]=BYTE; /* stupid DEC */
685: if (p->op==MOV || p->op==PUSH || p->op==CVT || p->op==MOVZ || p->op==COM || p->op==NEG) {
686: if (p->op==PUSH) cp1="-(sp)";
687: else {
688: cp1=regs[RT2];
689: if (0<=(r=isreg(cp1)) && r<NUSE && uses[r]==0)
690: uses[r]=olduse; /* reincarnation!! */
691: /* as in addl2 r0,r1; movl r1,r0; ret */
692: if (p->op!=MOV) cp1=0;
693: }
694: if (cp1) while (*cp2++= *cp1++);
695: else *cp2=0;
696: } else *cp2=0;
697: continue;
698: }
699: /* check for (r),(r)+,-(r),[r] */
700: do if (*cp1=='(' || *cp1=='[') {/* get register number */
701: char t;
702: cp2= ++cp1; while (*++cp1!=')' && *cp1!=']'); t= *cp1; *cp1=0;
703: if (0<=(r=isreg(cp2)) && r<NUSE && (uses[r]==0 || uses[r]==p)) {
704: uses[r]=p; regs[r][0]=(*--cp2=='[' ? OPX<<4 : OPB<<4);
705: }
706: *cp1=t;
707: } while (*++cp1);
708: }
709: /* pushax or movax possibility? */
710: cp1=regs[RT1];
711: if (*cp1++=='$' && 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 (r < NUSE && uses[r] == 0) {
727: uses[r]=p;
728: regs[r][0]=OPX<<4;
729: }
730: p->pop=0;
731: }
732: }
733: return(p);
734: }
735:
736: ispow2(n) register long n; {/* -1 -> no; else -> log to base 2 */
737: register int log;
738: if (n==0 || n&(n-1)) return(-1); log=0;
739: for (;;) {n >>= 1; if (n==0) return(log); ++log; if (n== -1) return(log);}
740: }
741:
742: bitopt(p) register struct node *p; {
743: /* change "bitx $<power_of_2>,a" followed by JEQ or JNE
744: /* into JBC or JBS. watch out for I/O registers. (?)
745: /* assumes that 'splitrand' has already been called.
746: */
747: register char *cp1,*cp2; int b;
748: cp1=regs[RT1]; cp2=regs[RT2];
749: if (*cp1++!='$' || !okio(cp2) || p->forw->op!=CBR || p->forw->subop&-2 ||
750: 0>(b=ispow2(getnum(cp1)))) return;
751: if (p->subop!=BYTE && !(b==0 && p->subop==LONG) &&
752: (source(cp2) || indexa(cp2))) return;
753: if (b>=bitsize[p->subop]) {/* you dummy! */
754: if (source(cp2)) {/* side effect: auto increment or decrement */
755: p->pop=0;
756: p->op=TST; --cp1; while (*cp1++= *cp2++);
757: regs[RT2][0]=0; newcode(p);
758: } else delnode(p);
759: p = p->forw;
760: if (p->subop==JEQ) {p->combop=JBR; p->pop=0;}
761: else delnode(p);
762: nchange++; nbj++; return;
763: }
764: if (cp1=p->forw->code) {/* destination is not an internal label */
765: cp2=regs[RT3]; while (*cp2++= *cp1++);
766: }
767: if (b==0 && (p->subop==LONG || !(source(regs[RT2]) || indexa(regs[RT2])))) {
768: /* JLB optimization, ala BLISS */
769: cp2=regs[RT1]; cp1=regs[RT2]; while (*cp2++= *cp1++);
770: cp2=regs[RT2]; cp1=regs[RT3]; while (*cp2++= *cp1++);
771: *(regs[RT3])=0; p->forw->subop += JLBC-JBC;
772: p->forw->pop=0;
773: } else {
774: cp1=regs[RT1]+1;
775: if (b>9) *cp1++= b/10 +'0'; *cp1++= b%10 +'0'; *cp1=0; /* $<bit_number> */
776: }
777: nbj++; newcode(p); p->combop = p->forw->combop+((JBC-JEQ)<<8);
778: p->labno = p->forw->labno; delnode(p->forw);
779: p->pop=0;
780: }
781:
782: isfield(n) register long n; {/* -1 -> no; else -> position of low bit */
783: register int p; register long t;
784: t= ((n-1)|n) +1;
785: if (n!=0 && (0==t || 0<=ispow2(t))) {
786: p=0; while(!(n&1)) {n >>= 1; ++p;} return(p);
787: } else return(-1);
788: }
789:
790: bixprep(p,bix) register struct node *p; {
791: /* initial setup, single-bit checking for bisopt, bicopt.
792: /* return: 0->don't bother any more; 1->worthwhile trying
793: */
794: register char *cp1,*cp2;
795: splitrand(p); cp1=regs[RT1]; cp2=regs[RT2];
796: if (*cp1++!='$' || 0>(pos=isfield(f=getnum(cp1)))
797: || !okio(cp2) || indexa(cp2) || source(cp2) || !okio(lastrand)) return(0);
798: f |= f-1; if (++f==0) siz=32-pos; else siz=ispow2(f)-pos;
799: if (siz==1 && pos>5 && (p->subop>>4)==OP2 && (p->subop&0xF)!=BYTE
800: && pos<bitsize[p->subop&0xF]) {
801: p->ref = insertl(p->forw); p->combop = CBR | (bix<<8);
802: p->pop=0;
803: p->labno = p->ref->labno;
804: if (pos>9) {*cp1++= pos/10 +'0'; pos %= 10;}
805: *cp1++=pos+'0'; *cp1=0; newcode(p); nbj++; return(0);
806: }
807: return(1);
808: }
809:
810:
811: struct node *
812: bicopt(p) register struct node *p; {
813: /* use field operations or MOVZ if possible. done as part of 'bflow'.
814: */
815: register char *cp1,*cp2; int r;
816: char src[C2_ASIZE];
817: char lhssiz, sop;
818: if (!bixprep(p,JBCC)) return(p);
819: if (f==0) {/* the BIC isolates low order bits */
820: siz=pos; pos=0;
821: if ((p->subop&0xF)==LONG && *(regs[RT2])!='$') {/* result of EXTZV is long */
822: /* save source of BICL in 'src' */
823: cp1=regs[RT2]; cp2=src; while (*cp2++= *cp1++);
824: if (p->back->op==ASH) {/* try for more */
825: splitrand(p->back); cp1=regs[RT1]; cp2=regs[RT3];
826: if (*cp1++=='$' && *(regs[RT2])!='$' && !indexa(regs[RT2])
827: && 0>(f=getnum(cp1)) && equstr(src,cp2)
828: && 0<=(r=isreg(cp2)) && r<NUSE
829: && siz-f <= 32) { /* a good ASH */
830: pos -= f; cp1=regs[RT2]; cp2=src; while (*cp2++= *cp1++);
831: delnode(p->back);
832: }
833: }
834: /*
835: * 'pos', 'siz' known; find out the size of the
836: * left-hand operand of what the bicl will turn into.
837: */
838: if (pos==0 && siz==16)
839: lhssiz = WORD; /* movzwl */
840: else
841: lhssiz = BYTE; /* movzbl or extzvl */
842: if (p->back->op==CVT || p->back->op==MOVZ) {/* greedy, aren't we? */
843: splitrand(p->back); cp1=regs[RT1]; cp2=regs[RT2];
844: /*
845: * If indexa(cp1) || autoid(cp1), the fold may
846: * still be OK if the CVT/MOVZ has the same
847: * size operand on its left size as what we
848: * will turn the bicl into.
849: * However, if the CVT is from a float or
850: * double, forget it!
851: */
852: sop = p->back->subop&0xF; /* type of LHS of CVT/MOVZ */
853: if (equstr(src,cp2) && okio(cp1)
854: && sop != FFLOAT && sop != DFLOAT
855: && sop != GFLOAT && sop != HFLOAT
856: && ((!indexa(cp1) && !autoid(cp1)) || lhssiz == sop)
857: && 0<=(r=isreg(cp2)) && r<NUSE
858: && bitsize[sop]>=(pos+siz)
859: && bitsize[p->back->subop>>4]>=(pos+siz)) {/* good CVT */
860: cp1=regs[RT1]; cp2=src; while (*cp2++= *cp1++);
861: delnode(p->back);
862: }
863: }
864: /* 'pos', 'siz' known; source of field is in 'src' */
865: splitrand(p); /* retrieve destination of BICL */
866: if ((siz==8 || siz==16) && pos==0) {
867: p->combop = T(MOVZ,U(lhssiz,LONG));
868: sprintf(line,"%s,%s",src,lastrand);
869: } else {
870: p->combop = T(EXTZV,LONG);
871: sprintf(line,"$%d,$%d,%s,%s",pos,siz,src,lastrand);
872: }
873: p->pop=0;
874: p->code = copy(line); nfield++; return(p);
875: }/* end EXTZV possibility */
876: }/* end low order bits */
877: /* unfortunately, INSV clears the condition codes, thus cannot be used */
878: /* else {/* see if BICL2 of positive field should be INSV $0 */
879: /* if (p->subop==(LONG | (OP2<<4)) && 6<=(pos+siz)) {
880: /* p->combop = INSV;
881: /* sprintf(line,"$0,$%d,$%d,%s",pos,siz,lastrand);
882: /* p->code = copy(line); nfield++; return(p);
883: /* }
884: /* }
885: */
886: return(p);
887: }
888:
889: jumpsw()
890: {
891: register struct node *p, *p1;
892: register struct node *tp;
893: long tl;
894: char *tcp;
895: int ti;
896: int nj;
897:
898: ti = 0;
899: nj = 0;
900: for (p=first.forw; p!=0; p = p->forw)
901: p->seq = ++ti;
902: for (p=first.forw; p!=0; p = p1) {
903: p1 = p->forw;
904: if (p->op == CBR && p1->op==JBR && p->ref && p1->ref
905: && abs(p->seq - p->ref->seq) > abs(p1->seq - p1->ref->seq)) {
906: if (p->ref==p1->ref)
907: continue;
908: p->subop = revbr[p->subop];
909: p->pop=0;
910: tp = p1->ref;
911: p1->ref = p->ref;
912: p->ref = tp;
913: tl = p1->labno;
914: p1->labno = p->labno;
915: p->labno = tl;
916: #ifdef COPYCODE
917: if (p->labno == 0) {
918: tcp = p1->code;
919: p1->code = p->code;
920: p->code = tcp;
921: }
922: #endif
923: nrevbr++;
924: nj++;
925: }
926: }
927: return(nj);
928: }
929:
930: addsob()
931: {
932: register struct node *p, *p1, *p2, *p3;
933:
934: for (p = &first; (p1 = p->forw)!=0; p = p1) {
935: if (p->combop==T(DEC,LONG) && p1->op==CBR) {
936: if (abs(p->seq - p1->ref->seq) > 8) continue;
937: if (p1->subop==JGE || p1->subop==JGT) {
938: if (p1->subop==JGE) p->combop=SOBGEQ; else p->combop=SOBGTR;
939: p->pop=0;
940: p->labno = p1->labno; delnode(p1); nsob++;
941: }
942: } else if (p->combop==T(INC,LONG)) {
943: if (p1->op==LABEL && p1->refc==1 && p1->forw->combop==T(CMP,LONG)
944: && (p2=p1->forw->forw)->combop==T(CBR,JLE)
945: && (p3=p2->ref->back)->combop==JBR && p3->ref==p1
946: && p3->forw->op==LABEL && p3->forw==p2->ref) {
947: /* change INC LAB: CMP to LAB: INC CMP */
948: p->back->forw=p1; p1->back=p->back;
949: p->forw=p1->forw; p1->forw->back=p;
950: p->back=p1; p1->forw=p;
951: p1=p->forw;
952: /* adjust beginning value by 1 */
953: p2=alloc(sizeof first); p2->combop=T(DEC,LONG);
954: p2->pop=0;
955: p2->forw=p3; p2->back=p3->back; p3->back->forw=p2;
956: p3->back=p2; p2->code=p->code; p2->labno=0;
957: }
958: if (p1->combop==T(CMP,LONG) && (p2=p1->forw)->op==CBR) {
959: register char *cp1,*cp2;
960: splitrand(p1); if (!equstr(p->code,regs[RT1])) continue;
961: if (abs(p->seq - p2->ref->seq)>8) {/* outside byte displ range */
962: if (p2->subop!=JLE) continue;
963: p->combop=T(ACB,LONG);
964: cp2=regs[RT1]; cp1=regs[RT2]; while (*cp2++= *cp1++); /* limit */
965: cp2=regs[RT2]; cp1="$1"; while (*cp2++= *cp1++); /* increment */
966: cp2=regs[RT3]; cp1=p->code; while (*cp2++= *cp1++); /* index */
967: p->pop=0; newcode(p);
968: p->labno = p2->labno; delnode(p2); delnode(p1); nsob++;
969: } else if (p2->subop==JLE || p2->subop==JLT) {
970: if (p2->subop==JLE) p->combop=AOBLEQ; else p->combop=AOBLSS;
971: cp2=regs[RT1]; cp1=regs[RT2]; while (*cp2++= *cp1++); /* limit */
972: cp2=regs[RT2]; cp1=p->code; while (*cp2++= *cp1++); /* index */
973: p->pop=0; newcode(p);
974: p->labno = p2->labno; delnode(p2); delnode(p1); nsob++;
975: }
976: }
977: }
978: }
979: }
980:
981: equop(p1, p2)
982: register struct node *p1;
983: struct node *p2;
984: {
985: register char *cp1, *cp2;
986:
987: if (p1->combop != p2->combop)
988: return(0);
989: if (p1->op>0 && p1->op<MOV)
990: return(0);
991: switch (p1->combop) {
992: case EROU: case JSW: case TEXT: case DATA:
993: case BSS: case ALIGN: case WGEN: case END:
994: /*
995: * Consider all pseudo-ops to be unique.
996: */
997: return(0);
998: }
999: if (p1->op==MOVA && p1->labno!=p2->labno) return(0);
1000: cp1 = p1->code;
1001: cp2 = p2->code;
1002: if (cp1==0 && cp2==0)
1003: return(1);
1004: if (cp1==0 || cp2==0)
1005: return(0);
1006: while (*cp1 == *cp2++)
1007: if (*cp1++ == 0)
1008: return(1);
1009: return(0);
1010: }
1011:
1012: #ifndef delnode
1013: delnode(p) register struct node *p; {
1014: p->back->forw = p->forw;
1015: p->forw->back = p->back;
1016: }
1017: #endif
1018:
1019: #ifndef decref
1020: decref(p)
1021: register struct node *p;
1022: {
1023: if (p && --p->refc <= 0) {
1024: nrlab++;
1025: delnode(p);
1026: }
1027: }
1028: #endif
1029:
1030: struct node *
1031: nonlab(ap)
1032: struct node *ap;
1033: {
1034: register struct node *p;
1035:
1036: p = ap;
1037: while (p && p->op==LABEL)
1038: p = p->forw;
1039: return(p);
1040: }
1041:
1042: clearuse() {
1043: register struct node **i;
1044: for (i=uses+NUSE; i>uses;) *--i=0;
1045: }
1046:
1047: clearreg() {
1048: register char **i;
1049: for (i=regs; i<regs+NREG; ++i) {
1050: **i = 0;
1051: *(*i+1) = 0;
1052: }
1053: conloc[0] = 0;
1054: ccloc[0] = 0;
1055: }
1056:
1057: savereg(ai, s, type)
1058: register char *s;
1059: {
1060: register char *p, *sp;
1061:
1062: sp = p = regs[ai];
1063: if (source(s)) /* side effects in addressing */
1064: return;
1065: /* if any indexing, must be parameter or local */
1066: /* indirection (as in "*-4(fp)") is ok, however */
1067: *p++ = type;
1068: while (*p++ = *s)
1069: if (*s=='[' || *s++=='(' && *s!='a' && *s!='f') {*sp = 0; return;}
1070: }
1071:
1072: dest(s,type)
1073: register char *s;
1074: {
1075: register int i;
1076:
1077: (void) source(s); /* handle addressing side effects */
1078: if (!natural(s)) {
1079: /* wild store, everything except constants vanishes */
1080: for (i=NREG; --i>=0;)
1081: if (regs[i][1] != '$')
1082: regs[i][0] = regs[i][1] = 0;
1083: conloc[0] = 0; ccloc[0] = 0;
1084: return;
1085: }
1086: if ((i = isreg(s)) >= 0) {
1087: /* if register destination, that reg is a goner */
1088: regs[i][0] = regs[i][1] = 0;
1089: switch(type & 0xF){
1090: case DFLOAT: /* clobber two at once */
1091: /*FALLTHROUGH*/
1092: case GFLOAT:
1093: regs[i+1][0] = regs[i+1][1] = 0;
1094: break;
1095: case HFLOAT: /* clobber four at once */
1096: regs[i+1][0] = regs[i+1][1] = 0;
1097: regs[i+2][0] = regs[i+2][1] = 0;
1098: regs[i+3][0] = regs[i+3][1] = 0;
1099: break;
1100: }
1101: switch((type>>4)&0xF){
1102: case DFLOAT: /* clobber two at once */
1103: /*FALLTHROUGH*/
1104: case GFLOAT:
1105: regs[i+1][0] = regs[i+1][1] = 0;
1106: break;
1107: case HFLOAT: /* clobber four at once */
1108: regs[i+1][0] = regs[i+1][1] = 0;
1109: regs[i+2][0] = regs[i+2][1] = 0;
1110: regs[i+3][0] = regs[i+3][1] = 0;
1111: break;
1112: }
1113: }
1114: for (i=NREG; --i>=0;)
1115: if (regs[i][1]=='*' && equstr(s, regs[i]+2))
1116: regs[i][0] = regs[i][1] = 0; /* previous indirection through destination is invalid */
1117: while ((i = findrand(s,0)) >= 0) /* previous values of destination are invalid */
1118: regs[i][0] = regs[i][1] = 0;
1119: if (*conloc && equstr(conloc, s))
1120: conloc[0] = 0;
1121: setcc(s, type); /* natural destinations set condition codes */
1122: }
1123:
1124: /* separate operands at commas, set up 'regs' and 'lastrand' */
1125: splitrand(p) struct node *p; {
1126: register char *p1, *p2;
1127: register char **preg;
1128:
1129: preg = regs+RT1;
1130: if (p1 = p->code)
1131: while (*p1) {
1132: lastrand = p2 = *preg++;
1133: while (*p1)
1134: if (',' == (*p2++ = *p1++)) {
1135: --p2;
1136: break;
1137: }
1138: *p2 = 0;
1139: }
1140: while (preg < (regs+RT1+5))
1141: *(*preg++) = 0;
1142: }
1143:
1144: compat(have, want) {
1145: register int hsrc, hdst;
1146: if (0==(want &= 0xF)) return(1); /* anything satisfies a wildcard want */
1147: hsrc=have&0xF;
1148: if (0==(hdst=((have>>4)&0xF)) || (hdst>=OP2 && hdst<=OPX)) hdst=hsrc;
1149: if (want>=FFLOAT) return(hdst==want && hsrc==want);
1150: /* FLOAT, DFLOAT not compat: rounding */
1151: return(hsrc>=want && hdst>=want && hdst<FFLOAT);
1152: }
1153:
1154: equtype(t1,t2) {return(compat(t1,t2) && compat(t2,t1));}
1155:
1156: findrand(as, type)
1157: char *as;
1158: {
1159: register char **i;
1160: for (i = regs+NREG; --i>=regs;) {
1161: if (**i && equstr(*i+1, as) && compat(**i,type))
1162: return(i-regs);
1163: }
1164: return(-1);
1165: }
1166:
1167: isreg(s)
1168: register char *s;
1169: {
1170: if (*s++!='r' || !isdigit(*s++)) return(-1);
1171: if (*s==0) return(*--s-'0');
1172: if (*(s-1)=='1' && isdigit(*s++) && *s==0) return(10+*--s-'0');
1173: return(-1);
1174: }
1175:
1176: check()
1177: {
1178: register struct node *p, *lp;
1179:
1180: lp = &first;
1181: for (p=first.forw; p!=0; p = p->forw) {
1182: if (p->back != lp) {
1183: fprintf(stderr, "c2: failed internal consistency check -- help!\n");
1184: exit(-1);
1185: }
1186: lp = p;
1187: }
1188: }
1189:
1190: source(ap)
1191: char *ap;
1192: {
1193: register char *p1, *p2;
1194:
1195: p1 = ap;
1196: p2 = p1;
1197: if (*p1==0)
1198: return(0);
1199: while (*p2++ && *(p2-1)!='[');
1200: if (*p1=='-' && *(p1+1)=='('
1201: || *p1=='*' && *(p1+1)=='-' && *(p1+2)=='('
1202: || *(p2-2)=='+') {
1203: while (*p1 && *p1++!='r');
1204: if (isdigit(*p1++))
1205: if (isdigit(*p1))
1206: regs[10+*p1-'0'][0] = regs[10+*p1-'0'][1] = 0;
1207: else {
1208: --p1;
1209: regs[*p1-'0'][0] = regs[*p1-'0'][1] = 0;
1210: }
1211: return(1);
1212: }
1213: return(0);
1214: }
1215:
1216: newcode(p) struct node *p; {
1217: register char *p1,*p2,**preg;
1218: preg=regs+RT1; p2=line;
1219: while (*(p1= *preg++)) {while (*p2++= *p1++); *(p2-1)=',';}
1220: *--p2=0;
1221: p->code=copy(line);
1222: }
1223:
1224: repladdr(p)
1225: struct node *p;
1226: {
1227: register r;
1228: register char *p1;
1229: char **preg; int nrepl;
1230:
1231: preg=regs+RT1; nrepl=0;
1232: while (lastrand!=(p1= *preg++))
1233: if (!source(p1) && 0<=(r=findrand(p1,p->subop))) {
1234: *p1++='r'; if (r>9) {*p1++='1'; r -= 10;} *p1++=r+'0'; *p1=0;
1235: nrepl++; nsaddr++;
1236: }
1237: if (nrepl) newcode(p);
1238: }
1239:
1240: /* movedat()
1241: /* {
1242: /* register struct node *p1, *p2;
1243: /* struct node *p3;
1244: /* register seg;
1245: /* struct node data;
1246: /* struct node *datp;
1247: /*
1248: /* if (first.forw == 0)
1249: /* return;
1250: /* datp = &data;
1251: /* for (p1 = first.forw; p1!=0; p1 = p1->forw) {
1252: /* if (p1->op == DATA) {
1253: /* p2 = p1->forw;
1254: /* while (p2 && p2->op!=TEXT)
1255: /* p2 = p2->forw;
1256: /* if (p2==0)
1257: /* break;
1258: /* p3 = p1->back;
1259: /* p1->back->forw = p2->forw;
1260: /* p2->forw->back = p3;
1261: /* p2->forw = 0;
1262: /* datp->forw = p1;
1263: /* p1->back = datp;
1264: /* p1 = p3;
1265: /* datp = p2;
1266: /* }
1267: /* }
1268: /* if (data.forw) {
1269: /* datp->forw = first.forw;
1270: /* first.forw->back = datp;
1271: /* data.forw->back = &first;
1272: /* first.forw = data.forw;
1273: /* }
1274: /* seg = -1;
1275: /* for (p1 = first.forw; p1!=0; p1 = p1->forw) {
1276: /* if (p1->op==TEXT||p1->op==DATA||p1->op==BSS) {
1277: /* if (p1->op == seg || p1->forw&&p1->forw->op==seg) {
1278: /* p1->back->forw = p1->forw;
1279: /* p1->forw->back = p1->back;
1280: /* p1 = p1->back;
1281: /* continue;
1282: /* }
1283: /* seg = p1->op;
1284: /* }
1285: /* }
1286: /* }
1287: */
1288:
1289: redunbr(p)
1290: register struct node *p;
1291: {
1292: register struct node *p1;
1293: register char *ap1;
1294: char *ap2;
1295:
1296: if ((p1 = p->ref) == 0)
1297: return;
1298: p1 = nonlab(p1);
1299: if (p1->op==TST) {
1300: splitrand(p1);
1301: savereg(RT2, "$0", p1->subop);
1302: } else if (p1->op==CMP)
1303: splitrand(p1);
1304: else
1305: return;
1306: if (p1->forw->op==CBR) {
1307: ap1 = findcon(RT1, p1->subop);
1308: ap2 = findcon(RT2, p1->subop);
1309: p1 = p1->forw;
1310: if (compare(p1->subop, ap1, ap2)) {
1311: nredunj++;
1312: nchange++;
1313: decref(p->ref);
1314: p->ref = p1->ref;
1315: p->labno = p1->labno;
1316: #ifdef COPYCODE
1317: if (p->labno == 0)
1318: p->code = p1->code;
1319: #endif
1320: if (p->ref)
1321: p->ref->refc++;
1322: }
1323: } else if (p1->op==TST && equstr(regs[RT1],ccloc+1) &&
1324: equtype(ccloc[0],p1->subop)) {
1325: p1=insertl(p1->forw); decref(p->ref); p->ref=p1;
1326: nrtst++; nchange++;
1327: }
1328: }
1329:
1330: char *
1331: findcon(i, type)
1332: {
1333: register char *p;
1334: register r;
1335:
1336: p = regs[i];
1337: if (*p=='$')
1338: return(p);
1339: if ((r = isreg(p)) >= 0 && compat(regs[r][0],type))
1340: return(regs[r]+1);
1341: if (equstr(p, conloc))
1342: return(conval+1);
1343: return(p);
1344: }
1345:
1346: compare(opc, acp1, acp2)
1347: char *acp1, *acp2;
1348: {
1349: register char *cp1, *cp2;
1350: register n1;
1351: int n2; int sign;
1352:
1353: cp1 = acp1;
1354: cp2 = acp2;
1355: if (*cp1++ != '$' || *cp2++ != '$')
1356: return(0);
1357: n1 = 0; sign=1; if (*cp2=='-') {++cp2; sign= -1;}
1358: while (isdigit(*cp2)) {n1 *= 10; n1 += (*cp2++ - '0')*sign;}
1359: n2 = n1;
1360: n1 = 0; sign=1; if (*cp1=='-') {++cp1; sign= -1;}
1361: while (isdigit(*cp1)) {n1 *= 10; n1 += (*cp1++ - '0')*sign;}
1362: if (*cp1=='+')
1363: cp1++;
1364: if (*cp2=='+')
1365: cp2++;
1366: do {
1367: if (*cp1++ != *cp2)
1368: return(0);
1369: } while (*cp2++);
1370: switch(opc) {
1371:
1372: case JEQ:
1373: return(n1 == n2);
1374: case JNE:
1375: return(n1 != n2);
1376: case JLE:
1377: return(n1 <= n2);
1378: case JGE:
1379: return(n1 >= n2);
1380: case JLT:
1381: return(n1 < n2);
1382: case JGT:
1383: return(n1 > n2);
1384: case JLO:
1385: return((unsigned) n1 < (unsigned) n2);
1386: case JHI:
1387: return((unsigned) n1 > (unsigned) n2);
1388: case JLOS:
1389: return((unsigned) n1 <= (unsigned) n2);
1390: case JHIS:
1391: return((unsigned) n1 >= (unsigned) n2);
1392: }
1393: return(0);
1394: }
1395:
1396: setcon(cv, cl, type)
1397: register char *cv, *cl;
1398: {
1399: register char *p;
1400:
1401: if (*cv != '$')
1402: return;
1403: if (!natural(cl))
1404: return;
1405: p = conloc;
1406: while (*p++ = *cl++);
1407: p = conval;
1408: *p++ = type;
1409: while (*p++ = *cv++);
1410: }
1411:
1412: equstr(p1, p2)
1413: register char *p1, *p2;
1414: {
1415: do {
1416: if (*p1++ != *p2)
1417: return(0);
1418: } while (*p2++);
1419: return(1);
1420: }
1421:
1422: setcc(ap,type)
1423: char *ap;
1424: {
1425: register char *p, *p1;
1426:
1427: p = ap;
1428: if (!natural(p)) {
1429: ccloc[0] = 0;
1430: return;
1431: }
1432: p1 = ccloc;
1433: *p1++ = type;
1434: while (*p1++ = *p++);
1435: }
1436:
1437: okio(p) register char *p; {/* 0->probable I/O space address; 1->not */
1438: if (ioflag && (!natural(p) || 0>getnum(p))) return(0);
1439: return(1);
1440: }
1441:
1442: indexa(p) register char *p; {/* 1-> uses [r] addressing mode; 0->doesn't */
1443: while (*p) if (*p++=='[') return(1);
1444: return(0);
1445: }
1446:
1447: natural(p)
1448: register char *p;
1449: {/* 1->simple local, parameter, global, or register; 0->otherwise */
1450: if (*p=='*' || *p=='(' || *p=='-'&&p[1]=='(' || *p=='$'&&getnum(p+1))
1451: return(0);
1452: while (*p++);
1453: p--;
1454: if (*--p=='+' || *p==']' || *p==')' && p[-2]!='a' && p[-2]!='f')
1455: return(0);
1456: return(1);
1457: }
1458:
1459: /*
1460: ** Tell if an argument is most likely static.
1461: */
1462:
1463: isstatic(cp)
1464: register char *cp;
1465: {
1466: if (*cp == '_' || *cp == 'L' || (*cp++ == 'v' && *cp == '.'))
1467: return (1);
1468: return (0);
1469: }
1470:
1471: autoid(p) register char *p; {/* 1-> uses autoincrement/autodecrement; 0->doesn't */
1472: if (*p == '-' && *(p+1) == '(') return(1);
1473: while (*p) p++;
1474: if (*--p == '+' && *--p == ')') return(1);
1475: return(0);
1476: }
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