1 #ifndef lint 2 static char sccsid[] = "@(#)c21.c 4.15 03/19/85"; 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 } 263 goto std; 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 (uses[r]==0) {uses[r]=p; regs[r][0]=OPX<<4;} 727 p->pop=0; 728 } 729 } 730 return(p); 731 } 732 733 ispow2(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 } 738 739 bitopt(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; /* $<bit_number> */ 771 } 772 nbj++; newcode(p); p->combop = p->forw->combop+((JBC-JEQ)<<8); 773 p->labno = p->forw->labno; delnode(p->forw); 774 p->pop=0; 775 } 776 777 isfield(n) register long n; {/* -1 -> no; else -> position of low bit */ 778 register int p; register long t; 779 t= ((n-1)|n) +1; 780 if (n!=0 && (0==t || 0<=ispow2(t))) { 781 p=0; while(!(n&1)) {n >>= 1; ++p;} return(p); 782 } else return(-1); 783 } 784 785 bixprep(p,bix) register struct node *p; { 786 /* initial setup, single-bit checking for bisopt, bicopt. 787 /* return: 0->don't bother any more; 1->worthwhile trying 788 */ 789 register char *cp1,*cp2; 790 splitrand(p); cp1=regs[RT1]; cp2=regs[RT2]; 791 if (*cp1++!='$' || 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 } 804 805 806 struct node * 807 bicopt(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; 811 char src[C2_ASIZE]; 812 char lhssiz, sop; 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])!='$' && !indexa(regs[RT2]) 822 && 0>(f=getnum(cp1)) && equstr(src,cp2) 823 && 0<=(r=isreg(cp2)) && r<NUSE 824 && siz-f <= 32) { /* a good ASH */ 825 pos -= f; cp1=regs[RT2]; cp2=src; while (*cp2++= *cp1++); 826 delnode(p->back); 827 } 828 } 829 /* 830 * 'pos', 'siz' known; find out the size of the 831 * left-hand operand of what the bicl will turn into. 832 */ 833 if (pos==0 && siz==16) 834 lhssiz = WORD; /* movzwl */ 835 else 836 lhssiz = BYTE; /* movzbl or extzvl */ 837 if (p->back->op==CVT || p->back->op==MOVZ) {/* greedy, aren't we? */ 838 splitrand(p->back); cp1=regs[RT1]; cp2=regs[RT2]; 839 /* 840 * If indexa(cp1) || autoid(cp1), the fold may 841 * still be OK if the CVT/MOVZ has the same 842 * size operand on its left size as what we 843 * will turn the bicl into. 844 * However, if the CVT is from a float or 845 * double, forget it! 846 */ 847 sop = p->back->subop&0xF; /* type of LHS of CVT/MOVZ */ 848 if (equstr(src,cp2) && okio(cp1) 849 && sop != FFLOAT && sop != DFLOAT 850 && sop != GFLOAT && sop != HFLOAT 851 && ((!indexa(cp1) && !autoid(cp1)) || lhssiz == sop) 852 && 0<=(r=isreg(cp2)) && r<NUSE 853 && bitsize[sop]>=(pos+siz) 854 && bitsize[p->back->subop>>4]>=(pos+siz)) {/* good CVT */ 855 cp1=regs[RT1]; cp2=src; while (*cp2++= *cp1++); 856 delnode(p->back); 857 } 858 } 859 /* 'pos', 'siz' known; source of field is in 'src' */ 860 splitrand(p); /* retrieve destination of BICL */ 861 if ((siz==8 || siz==16) && pos==0) { 862 p->combop = T(MOVZ,U(lhssiz,LONG)); 863 sprintf(line,"%s,%s",src,lastrand); 864 } else { 865 p->combop = T(EXTZV,LONG); 866 sprintf(line,"$%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 } 883 884 jumpsw() 885 { 886 register struct node *p, *p1; 887 register struct node *tp; 888 long tl; 889 char *tcp; 890 int ti; 891 int nj; 892 893 ti = 0; 894 nj = 0; 895 for (p=first.forw; p!=0; p = p->forw) 896 p->seq = ++ti; 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; 905 tp = p1->ref; 906 p1->ref = p->ref; 907 p->ref = tp; 908 tl = p1->labno; 909 p1->labno = p->labno; 910 p->labno = tl; 911 #ifdef COPYCODE 912 if (p->labno == 0) { 913 tcp = p1->code; 914 p1->code = p->code; 915 p->code = tcp; 916 } 917 #endif 918 nrevbr++; 919 nj++; 920 } 921 } 922 return(nj); 923 } 924 925 addsob() 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) { 931 if (abs(p->seq - p1->ref->seq) > 8) continue; 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; 956 if (abs(p->seq - p2->ref->seq)>8) {/* outside byte displ range */ 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 } 975 976 equop(p1, p2) 977 register struct node *p1; 978 struct 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); 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 } 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 1007 #ifndef delnode 1008 delnode(p) register struct node *p; { 1009 p->back->forw = p->forw; 1010 p->forw->back = p->back; 1011 } 1012 #endif 1013 1014 #ifndef decref 1015 decref(p) 1016 register struct node *p; 1017 { 1018 if (p && --p->refc <= 0) { 1019 nrlab++; 1020 delnode(p); 1021 } 1022 } 1023 #endif 1024 1025 struct node * 1026 nonlab(ap) 1027 struct 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 1037 clearuse() { 1038 register struct node **i; 1039 for (i=uses+NUSE; i>uses;) *--i=0; 1040 } 1041 1042 clearreg() { 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; 1050 } 1051 1052 savereg(ai, s, type) 1053 register 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 1067 dest(s,type) 1068 register char *s; 1069 { 1070 register int i; 1071 1072 (void) source(s); /* handle addressing side effects */ 1073 if (!natural(s)) { 1074 /* wild store, everything except constants vanishes */ 1075 for (i=NREG; --i>=0;) 1076 if (regs[i][1] != '$') 1077 regs[i][0] = regs[i][1] = 0; 1078 conloc[0] = 0; ccloc[0] = 0; 1079 return; 1080 } 1081 if ((i = isreg(s)) >= 0) { 1082 /* if register destination, that reg is a goner */ 1083 regs[i][0] = regs[i][1] = 0; 1084 switch(type & 0xF){ 1085 case DFLOAT: /* clobber two at once */ 1086 /*FALLTHROUGH*/ 1087 case GFLOAT: 1088 regs[i+1][0] = regs[i+1][1] = 0; 1089 break; 1090 case HFLOAT: /* clobber four at once */ 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; 1094 break; 1095 } 1096 switch((type>>4)&0xF){ 1097 case DFLOAT: /* clobber two at once */ 1098 /*FALLTHROUGH*/ 1099 case GFLOAT: 1100 regs[i+1][0] = regs[i+1][1] = 0; 1101 break; 1102 case HFLOAT: /* clobber four at once */ 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; 1106 break; 1107 } 1108 } 1109 for (i=NREG; --i>=0;) 1110 if (regs[i][1]=='*' && equstr(s, regs[i]+2)) 1111 regs[i][0] = regs[i][1] = 0; /* previous indirection through destination is invalid */ 1112 while ((i = findrand(s,0)) >= 0) /* previous values of destination are invalid */ 1113 regs[i][0] = regs[i][1] = 0; 1114 if (*conloc && equstr(conloc, s)) 1115 conloc[0] = 0; 1116 setcc(s, type); /* natural destinations set condition codes */ 1117 } 1118 1119 /* separate operands at commas, set up 'regs' and 'lastrand' */ 1120 splitrand(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; 1137 } 1138 1139 compat(have, want) { 1140 register int hsrc, hdst; 1141 if (0==(want &= 0xF)) return(1); /* anything satisfies a wildcard want */ 1142 hsrc=have&0xF; if (0==(hdst=((have>>4)&0xF)) || hdst>=OP2) hdst=hsrc; 1143 if (want>=FFLOAT) return(hdst==want && hsrc==want); 1144 /* FLOAT, DFLOAT not compat: rounding */ 1145 return(hsrc>=want && hdst>=want && hdst<FFLOAT); 1146 } 1147 1148 equtype(t1,t2) {return(compat(t1,t2) && compat(t2,t1));} 1149 1150 findrand(as, type) 1151 char *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 1161 isreg(s) 1162 register 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 1170 check() 1171 { 1172 register struct node *p, *lp; 1173 1174 lp = &first; 1175 for (p=first.forw; p!=0; p = p->forw) { 1176 if (p->back != lp) { 1177 fprintf(stderr, "c2: failed internal consistency check -- help!\n"); 1178 exit(-1); 1179 } 1180 lp = p; 1181 } 1182 } 1183 1184 source(ap) 1185 char *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++)) 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 } 1205 return(1); 1206 } 1207 return(0); 1208 } 1209 1210 newcode(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 1218 repladdr(p) 1219 struct node *p; 1220 { 1221 register r; 1222 register char *p1; 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 1283 redunbr(p) 1284 register 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, "$0", p1->subop); 1296 } else if (p1->op==CMP) 1297 splitrand(p1); 1298 else 1299 return; 1300 if (p1->forw->op==CBR) { 1301 ap1 = findcon(RT1, p1->subop); 1302 ap2 = findcon(RT2, p1->subop); 1303 p1 = p1->forw; 1304 if (compare(p1->subop, ap1, ap2)) { 1305 nredunj++; 1306 nchange++; 1307 decref(p->ref); 1308 p->ref = p1->ref; 1309 p->labno = p1->labno; 1310 #ifdef COPYCODE 1311 if (p->labno == 0) 1312 p->code = p1->code; 1313 #endif 1314 if (p->ref) 1315 p->ref->refc++; 1316 } 1317 } else if (p1->op==TST && equstr(regs[RT1],ccloc+1) && 1318 equtype(ccloc[0],p1->subop)) { 1319 p1=insertl(p1->forw); decref(p->ref); p->ref=p1; 1320 nrtst++; nchange++; 1321 } 1322 } 1323 1324 char * 1325 findcon(i, type) 1326 { 1327 register char *p; 1328 register r; 1329 1330 p = regs[i]; 1331 if (*p=='$') 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 1340 compare(opc, acp1, acp2) 1341 char *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++); 1364 switch(opc) { 1365 1366 case JEQ: 1367 return(n1 == n2); 1368 case JNE: 1369 return(n1 != n2); 1370 case JLE: 1371 return(n1 <= n2); 1372 case JGE: 1373 return(n1 >= n2); 1374 case JLT: 1375 return(n1 < n2); 1376 case JGT: 1377 return(n1 > n2); 1378 case JLO: 1379 return((unsigned) n1 < (unsigned) n2); 1380 case JHI: 1381 return((unsigned) n1 > (unsigned) n2); 1382 case JLOS: 1383 return((unsigned) n1 <= (unsigned) n2); 1384 case JHIS: 1385 return((unsigned) n1 >= (unsigned) n2); 1386 } 1387 return(0); 1388 } 1389 1390 setcon(cv, cl, type) 1391 register char *cv, *cl; 1392 { 1393 register char *p; 1394 1395 if (*cv != '$') 1396 return; 1397 if (!natural(cl)) 1398 return; 1399 p = conloc; 1400 while (*p++ = *cl++); 1401 p = conval; 1402 *p++ = type; 1403 while (*p++ = *cv++); 1404 } 1405 1406 equstr(p1, p2) 1407 register char *p1, *p2; 1408 { 1409 do { 1410 if (*p1++ != *p2) 1411 return(0); 1412 } while (*p2++); 1413 return(1); 1414 } 1415 1416 setcc(ap,type) 1417 char *ap; 1418 { 1419 register char *p, *p1; 1420 1421 p = ap; 1422 if (!natural(p)) { 1423 ccloc[0] = 0; 1424 return; 1425 } 1426 p1 = ccloc; 1427 *p1++ = type; 1428 while (*p1++ = *p++); 1429 } 1430 1431 okio(p) register char *p; {/* 0->probable I/O space address; 1->not */ 1432 if (ioflag && (!natural(p) || 0>getnum(p))) return(0); 1433 return(1); 1434 } 1435 1436 indexa(p) register char *p; {/* 1-> uses [r] addressing mode; 0->doesn't */ 1437 while (*p) if (*p++=='[') return(1); 1438 return(0); 1439 } 1440 1441 natural(p) 1442 register char *p; 1443 {/* 1->simple local, parameter, global, or register; 0->otherwise */ 1444 if (*p=='*' || *p=='(' || *p=='-'&&p[1]=='(' || *p=='$'&&getnum(p+1)) 1445 return(0); 1446 while (*p++); 1447 p--; 1448 if (*--p=='+' || *p==']' || *p==')' && p[-2]!='a' && p[-2]!='f') 1449 return(0); 1450 return(1); 1451 } 1452 1453 /* 1454 ** Tell if an argument is most likely static. 1455 */ 1456 1457 isstatic(cp) 1458 register char *cp; 1459 { 1460 if (*cp == '_' || *cp == 'L' || (*cp++ == 'v' && *cp == '.')) 1461 return (1); 1462 return (0); 1463 } 1464 1465 autoid(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 } 1471