1 #ifndef lint 2 static char sccsid[] = "@(#)c21.c 4.22 12/11/87"; 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 ((p->op==CVT || p->op==MOVZ) 581 && (p->forw->op==CVT || p->forw->op==MOVZ) 582 && p->forw->subop&0xf 583 && equtype(p->subop,p->forw->subop) 584 && !source(cp1=regs[RT1]) 585 && !indexa(cp1)) goto movit; 586 if (equtype(p->subop,regs[r][0]) 587 || ((p->op==CVT || p->op==MOVZ) 588 && 0xf®s[r][0] && compat(0xf&(p->subop>>4),regs[r][0]))) { 589 register int r2; 590 if (regs[r][1]!=0) {/* send directly to destination */ 591 if (p->op==INC || p->op==DEC) { 592 if (p->op==DEC) p->op=SUB; else p->op=ADD; 593 p->subop=(OP2<<4)+(p->subop&0xF); /* use 2 now, convert to 3 later */ 594 p->pop=0; 595 cp1=lastrand; cp2=regs[RT2]; while (*cp2++= *cp1++); /* copy reg */ 596 cp1=lastrand; *cp1++='$'; *cp1++='1'; *cp1=0; 597 } 598 cp1=regs[r]+1; cp2=lastrand; 599 if (OP2==(p->subop>>4)) {/* use 3 operand form of instruction */ 600 p->pop=0; 601 p->subop += (OP3-OP2)<<4; lastrand=cp2=regs[RT3]; 602 } 603 while (*cp2++= *cp1++); 604 if (p->op==MOVA && p->forw->op==PUSH) { 605 p->op=PUSHA; *regs[RT2]=0; p->pop=0; 606 } else if (p->op==MOV && p->forw->op==PUSH) { 607 p->op=PUSH ; *regs[RT2]=0; p->pop=0; 608 } 609 delnode(p->forw); 610 if (0<=(r2=isreg(lastrand)) && r2<NUSE) { 611 uses[r2]=uses[r]; uses[r]=0; 612 } 613 (void) redun3(p,0); 614 newcode(p); redunm++; flow=r; 615 } else if (p->op==MOV && p->forw->op!=EXTV && p->forw->op!=EXTZV) { 616 /* superfluous fetch */ 617 int nmatch; 618 char src[C2_ASIZE]; 619 movit: 620 cp2=src; cp1=regs[RT1]; while (*cp2++= *cp1++); 621 splitrand(p->forw); 622 if (p->forw->op != INC && p->forw->op != DEC) 623 lastrand=byondrd(p->forw); 624 nmatch=0; 625 for (preg=regs+RT1;*preg!=lastrand;preg++) 626 if (r==isreg(*preg)) { 627 cp2= *preg; cp1=src; while (*cp2++= *cp1++); ++nmatch; 628 } 629 if (nmatch==1) { 630 if (OP2==(p->forw->subop>>4) && equstr(src,regs[RT2])) { 631 p->forw->pop=0; 632 p->forw->subop += (OP3-OP2)<<4; cp1=regs[RT3]; 633 *cp1++='r'; *cp1++=r+'0'; *cp1=0; 634 } 635 delnode(p); p=p->forw; 636 if (0<=(r2=isreg(src)) && r2<NUSE) { 637 uses[r2]=uses[r]; uses[r]=0; 638 } 639 (void) redun3(p,0); 640 newcode(p); redunm++; flow=r; 641 } else splitrand(p); 642 } 643 } else if (p->op==MOV && (p->forw->op==CVT || p->forw->op==MOVZ) 644 && p->forw->subop&0xf /* if base or index, then forget it */ 645 && compat(p->subop,p->forw->subop) && !source(cp1=regs[RT1]) 646 && !indexa(cp1)) goto movit; 647 } 648 /* adjust 'lastrand' past any 'read' or 'modify' operands. */ 649 lastrand=byondrd(p); 650 /* a 'write' clobbers the register. */ 651 if (0<=(r=isreg(lastrand)) && r<NUSE 652 || OP2==(p->subop>>4) && 0<=(r=isreg(regs[RT2])) && r<NUSE && uses[r]==0) { 653 /* writing a dead register is useless, but watch side effects */ 654 switch (p->op) { 655 case ACB: 656 case AOBLEQ: case AOBLSS: case SOBGTR: case SOBGEQ: break; 657 default: 658 if (uses[r]==0) {/* no direct uses, check for use of condition codes */ 659 register struct node *q=p; 660 while ((q=nonlab(q->forw))->combop==JBR) q=q->ref; /* cc unused, unchanged */ 661 if (q->op!=CBR) {/* ... and destroyed */ 662 preg=regs+RT1; 663 while (cp1= *preg++) { 664 if (cp1==lastrand) {redunm++; delnode(p); return(p->forw);} 665 if (source(cp1) || equstr(cp1,lastrand)) break; 666 } 667 } 668 } 669 flow=r; 670 } 671 } 672 if (0<=(r=flow)) { 673 olduse=uses[r]; 674 uses[r]=0; 675 regs[r][0]=regs[r][1]=0; 676 } 677 /* these two are here, rather than in bmove(), 678 /* because I decided that it was better to go for 3-address code 679 /* (save time) rather than fancy jbxx (save 1 byte) 680 /* on sequences like bisl2 $64,r0; movl r0,foo 681 */ 682 if (p->op==BIC) {p=bicopt(p); splitrand(p); lastrand=byondrd(p);} 683 if (p->op==BIS) {(void) bixprep(p,JBSS); lastrand=byondrd(p);} 684 /* now look for 'read' or 'modify' (read & write) uses */ 685 preg=regs+RT1; 686 while (*(cp1= *preg++)) { 687 /* check for r */ 688 if (lastrand!=cp1 && 0<=(r=isreg(cp1)) && r<NUSE && uses[r]==0) { 689 uses[r]=p; cp2=regs[r]; *cp2++=p->subop; 690 if (p->op==ASH && preg==(regs+RT1+1)) cp2[-1]=BYTE; /* stupid DEC */ 691 if (p->op==MOV || p->op==PUSH || p->op==CVT || p->op==MOVZ || p->op==COM || p->op==NEG) { 692 if (p->op==PUSH) cp1="-(sp)"; 693 else { 694 cp1=regs[RT2]; 695 if (0<=(r=isreg(cp1)) && r<NUSE && uses[r]==0) 696 uses[r]=olduse; /* reincarnation!! */ 697 /* as in addl2 r0,r1; movl r1,r0; ret */ 698 if (p->op!=MOV) cp1=0; 699 } 700 if (cp1) while (*cp2++= *cp1++); 701 else *cp2=0; 702 } else *cp2=0; 703 continue; 704 } 705 /* check for (r),(r)+,-(r),[r] */ 706 do if (*cp1=='(' || *cp1=='[') {/* get register number */ 707 char t; 708 cp2= ++cp1; while (*++cp1!=')' && *cp1!=']'); t= *cp1; *cp1=0; 709 if (0<=(r=isreg(cp2)) && r<NUSE && (uses[r]==0 || uses[r]==p)) { 710 uses[r]=p; regs[r][0]=(*--cp2=='[' ? OPX<<4 : OPB<<4); 711 } 712 *cp1=t; 713 } while (*++cp1); 714 } 715 /* pushax or movax possibility? */ 716 cp1=regs[RT1]; 717 if (*cp1++=='$' && isstatic(cp1) && natural(regs[RT1])) { 718 if (p->combop==T(MOV,LONG)) { 719 if (regs[RT1][1]=='L' && 0!=(p->labno=getnum(regs[RT1]+2))) { 720 cp1=p->code; while (*cp1++!=','); p->code= --cp1; 721 } 722 p->combop=T(MOVA,LONG); ++p->code; p->pop=0; 723 } else if (p->combop==T(PUSH,LONG)) { 724 p->combop=T(PUSHA,LONG); ++p->code; p->pop=0; 725 } else if ((p->combop&0xFFFF)==T(ADD,U(LONG,OP3)) 726 && 0<=(r=isreg(regs[RT2]))) { 727 cp1=cp2=p->code; ++cp1; 728 do *cp2++= *cp1; while (*cp1++!=','); cp2[-1]='['; 729 do *cp2++= *cp1; while (*cp1++!=','); cp2[-1]=']'; 730 if (!equstr(regs[RT3],"-(sp)")) p->combop=T(MOVA,BYTE); 731 else {p->combop=T(PUSHA,BYTE); *cp2=0;} 732 if (r < NUSE && uses[r] == 0) { 733 uses[r]=p; 734 regs[r][0]=OPX<<4; 735 } 736 p->pop=0; 737 } 738 } 739 return(p); 740 } 741 742 ispow2(n) register long n; {/* -1 -> no; else -> log to base 2 */ 743 register int log; 744 if (n==0 || n&(n-1)) return(-1); log=0; 745 for (;;) {n >>= 1; if (n==0) return(log); ++log; if (n== -1) return(log);} 746 } 747 748 bitopt(p) register struct node *p; { 749 /* change "bitx $<power_of_2>,a" followed by JEQ or JNE 750 /* into JBC or JBS. watch out for I/O registers. (?) 751 /* assumes that 'splitrand' has already been called. 752 */ 753 register char *cp1,*cp2; int b; 754 cp1=regs[RT1]; cp2=regs[RT2]; 755 if (*cp1++!='$' || !okio(cp2) || p->forw->op!=CBR || p->forw->subop&-2 || 756 0>(b=ispow2(getnum(cp1)))) return; 757 if (p->subop!=BYTE && !(b==0 && p->subop==LONG) && 758 (source(cp2) || indexa(cp2))) return; 759 if (b>=bitsize[p->subop]) {/* you dummy! */ 760 if (source(cp2)) {/* side effect: auto increment or decrement */ 761 p->pop=0; 762 p->op=TST; --cp1; while (*cp1++= *cp2++); 763 regs[RT2][0]=0; newcode(p); 764 } else delnode(p); 765 p = p->forw; 766 if (p->subop==JEQ) {p->combop=JBR; p->pop=0;} 767 else delnode(p); 768 nchange++; nbj++; return; 769 } 770 if (cp1=p->forw->code) {/* destination is not an internal label */ 771 cp2=regs[RT3]; while (*cp2++= *cp1++); 772 } 773 if (b==0 && (p->subop==LONG || !(source(regs[RT2]) || indexa(regs[RT2])))) { 774 /* JLB optimization, ala BLISS */ 775 cp2=regs[RT1]; cp1=regs[RT2]; while (*cp2++= *cp1++); 776 cp2=regs[RT2]; cp1=regs[RT3]; while (*cp2++= *cp1++); 777 *(regs[RT3])=0; p->forw->subop += JLBC-JBC; 778 p->forw->pop=0; 779 } else { 780 cp1=regs[RT1]+1; 781 if (b>9) *cp1++= b/10 +'0'; *cp1++= b%10 +'0'; *cp1=0; /* $<bit_number> */ 782 } 783 nbj++; newcode(p); p->combop = p->forw->combop+((JBC-JEQ)<<8); 784 p->labno = p->forw->labno; delnode(p->forw); 785 p->pop=0; 786 } 787 788 isfield(n) register long n; {/* -1 -> no; else -> position of low bit */ 789 register int p; register long t; 790 t= ((n-1)|n) +1; 791 if (n!=0 && (0==t || 0<=ispow2(t))) { 792 p=0; while(!(n&1)) {n >>= 1; ++p;} return(p); 793 } else return(-1); 794 } 795 796 bixprep(p,bix) register struct node *p; { 797 /* initial setup, single-bit checking for bisopt, bicopt. 798 /* return: 0->don't bother any more; 1->worthwhile trying 799 */ 800 register char *cp1,*cp2; 801 splitrand(p); cp1=regs[RT1]; cp2=regs[RT2]; 802 if (*cp1++!='$' || 0>(pos=isfield(f=getnum(cp1))) 803 || !okio(cp2) || indexa(cp2) || source(cp2) || !okio(lastrand)) return(0); 804 f |= f-1; if (++f==0) siz=32-pos; else siz=ispow2(f)-pos; 805 if (siz==1 && pos>5 && (p->subop>>4)==OP2 && (p->subop&0xF)!=BYTE 806 && pos<bitsize[p->subop&0xF]) { 807 p->ref = insertl(p->forw); p->combop = CBR | (bix<<8); 808 p->pop=0; 809 p->labno = p->ref->labno; 810 if (pos>9) {*cp1++= pos/10 +'0'; pos %= 10;} 811 *cp1++=pos+'0'; *cp1=0; newcode(p); nbj++; return(0); 812 } 813 return(1); 814 } 815 816 817 struct node * 818 bicopt(p) register struct node *p; { 819 /* use field operations or MOVZ if possible. done as part of 'bflow'. 820 */ 821 register char *cp1,*cp2; int r; 822 char src[C2_ASIZE]; 823 char lhssiz, sop; 824 if (!bixprep(p,JBCC)) return(p); 825 if (f==0) {/* the BIC isolates low order bits */ 826 siz=pos; pos=0; 827 if ((p->subop&0xF)==LONG && *(regs[RT2])!='$') {/* result of EXTZV is long */ 828 /* save source of BICL in 'src' */ 829 cp1=regs[RT2]; cp2=src; while (*cp2++= *cp1++); 830 if (p->back->op==ASH) {/* try for more */ 831 splitrand(p->back); cp1=regs[RT1]; cp2=regs[RT3]; 832 if (*cp1++=='$' && *(regs[RT2])!='$' && !indexa(regs[RT2]) 833 && 0>(f=getnum(cp1)) && equstr(src,cp2) 834 && 0<=(r=isreg(cp2)) && r<NUSE 835 && siz-f <= 32) { /* a good ASH */ 836 pos -= f; cp1=regs[RT2]; cp2=src; while (*cp2++= *cp1++); 837 delnode(p->back); 838 } 839 } 840 /* 841 * 'pos', 'siz' known; find out the size of the 842 * left-hand operand of what the bicl will turn into. 843 */ 844 if (pos==0 && siz==16) 845 lhssiz = WORD; /* movzwl */ 846 else 847 lhssiz = BYTE; /* movzbl or extzvl */ 848 if (p->back->op==CVT || p->back->op==MOVZ) {/* greedy, aren't we? */ 849 splitrand(p->back); cp1=regs[RT1]; cp2=regs[RT2]; 850 /* 851 * If indexa(cp1) || autoid(cp1), the fold may 852 * still be OK if the CVT/MOVZ has the same 853 * size operand on its left size as what we 854 * will turn the bicl into. 855 * However, if the CVT is from a float or 856 * double, forget it! 857 */ 858 sop = p->back->subop&0xF; /* type of LHS of CVT/MOVZ */ 859 if (equstr(src,cp2) && okio(cp1) 860 && sop != FFLOAT && sop != DFLOAT 861 && sop != GFLOAT && sop != HFLOAT 862 && ((!indexa(cp1) && !autoid(cp1)) || lhssiz == sop) 863 && 0<=(r=isreg(cp2)) && r<NUSE 864 && bitsize[sop]>=(pos+siz) 865 && bitsize[p->back->subop>>4]>=(pos+siz)) {/* good CVT */ 866 cp1=regs[RT1]; cp2=src; while (*cp2++= *cp1++); 867 delnode(p->back); 868 } 869 } 870 /* 'pos', 'siz' known; source of field is in 'src' */ 871 splitrand(p); /* retrieve destination of BICL */ 872 if ((siz==8 || siz==16) && pos==0) { 873 p->combop = T(MOVZ,U(lhssiz,LONG)); 874 sprintf(line,"%s,%s",src,lastrand); 875 } else { 876 p->combop = T(EXTZV,LONG); 877 sprintf(line,"$%d,$%d,%s,%s",pos,siz,src,lastrand); 878 } 879 p->pop=0; 880 p->code = copy(line); nfield++; return(p); 881 }/* end EXTZV possibility */ 882 }/* end low order bits */ 883 /* unfortunately, INSV clears the condition codes, thus cannot be used */ 884 /* else {/* see if BICL2 of positive field should be INSV $0 */ 885 /* if (p->subop==(LONG | (OP2<<4)) && 6<=(pos+siz)) { 886 /* p->combop = INSV; 887 /* sprintf(line,"$0,$%d,$%d,%s",pos,siz,lastrand); 888 /* p->code = copy(line); nfield++; return(p); 889 /* } 890 /* } 891 */ 892 return(p); 893 } 894 895 jumpsw() 896 { 897 register struct node *p, *p1; 898 register struct node *tp; 899 long tl; 900 char *tcp; 901 int ti; 902 int nj; 903 904 ti = 0; 905 nj = 0; 906 for (p=first.forw; p!=0; p = p->forw) 907 p->seq = ++ti; 908 for (p=first.forw; p!=0; p = p1) { 909 p1 = p->forw; 910 if (p->op == CBR && p1->op==JBR && p->ref && p1->ref 911 && abs(p->seq - p->ref->seq) > abs(p1->seq - p1->ref->seq)) { 912 if (p->ref==p1->ref) 913 continue; 914 p->subop = revbr[p->subop]; 915 p->pop=0; 916 tp = p1->ref; 917 p1->ref = p->ref; 918 p->ref = tp; 919 tl = p1->labno; 920 p1->labno = p->labno; 921 p->labno = tl; 922 #ifdef COPYCODE 923 if (p->labno == 0) { 924 tcp = p1->code; 925 p1->code = p->code; 926 p->code = tcp; 927 } 928 #endif 929 nrevbr++; 930 nj++; 931 } 932 } 933 return(nj); 934 } 935 936 addsob() 937 { 938 register struct node *p, *p1, *p2, *p3; 939 940 for (p = &first; (p1 = p->forw)!=0; p = p1) { 941 if (p->combop==T(DEC,LONG) && p1->op==CBR) { 942 if (abs(p->seq - p1->ref->seq) > 8) continue; 943 if (p1->subop==JGE || p1->subop==JGT) { 944 if (p1->subop==JGE) p->combop=SOBGEQ; else p->combop=SOBGTR; 945 p->pop=0; 946 p->labno = p1->labno; delnode(p1); nsob++; 947 } 948 } else if (p->combop==T(INC,LONG)) { 949 if (p1->op==LABEL && p1->refc==1 && p1->forw->combop==T(CMP,LONG) 950 && (p2=p1->forw->forw)->combop==T(CBR,JLE) 951 && (p3=p2->ref->back)->combop==JBR && p3->ref==p1 952 && p3->forw->op==LABEL && p3->forw==p2->ref) { 953 /* change INC LAB: CMP to LAB: INC CMP */ 954 p->back->forw=p1; p1->back=p->back; 955 p->forw=p1->forw; p1->forw->back=p; 956 p->back=p1; p1->forw=p; 957 p1=p->forw; 958 /* adjust beginning value by 1 */ 959 p2=alloc(sizeof first); p2->combop=T(DEC,LONG); 960 p2->pop=0; 961 p2->forw=p3; p2->back=p3->back; p3->back->forw=p2; 962 p3->back=p2; p2->code=p->code; p2->labno=0; 963 } 964 if (p1->combop==T(CMP,LONG) && (p2=p1->forw)->op==CBR) { 965 register char *cp1,*cp2; 966 splitrand(p1); if (!equstr(p->code,regs[RT1])) continue; 967 if (abs(p->seq - p2->ref->seq)>8) {/* outside byte displ range */ 968 if (p2->subop!=JLE) continue; 969 p->combop=T(ACB,LONG); 970 cp2=regs[RT1]; cp1=regs[RT2]; while (*cp2++= *cp1++); /* limit */ 971 cp2=regs[RT2]; cp1="$1"; while (*cp2++= *cp1++); /* increment */ 972 cp2=regs[RT3]; cp1=p->code; while (*cp2++= *cp1++); /* index */ 973 p->pop=0; newcode(p); 974 p->labno = p2->labno; delnode(p2); delnode(p1); nsob++; 975 } else if (p2->subop==JLE || p2->subop==JLT) { 976 if (p2->subop==JLE) p->combop=AOBLEQ; else p->combop=AOBLSS; 977 cp2=regs[RT1]; cp1=regs[RT2]; while (*cp2++= *cp1++); /* limit */ 978 cp2=regs[RT2]; cp1=p->code; while (*cp2++= *cp1++); /* index */ 979 p->pop=0; newcode(p); 980 p->labno = p2->labno; delnode(p2); delnode(p1); nsob++; 981 } 982 } 983 } 984 } 985 } 986 987 equop(p1, p2) 988 register struct node *p1; 989 struct node *p2; 990 { 991 register char *cp1, *cp2; 992 993 if (p1->combop != p2->combop) 994 return(0); 995 if (p1->combop == 0 && p1->pop != p2->pop) 996 return(0); 997 if (p1->op>0 && p1->op<MOV) 998 return(0); 999 switch (p1->combop) { 1000 case EROU: case JSW: case TEXT: case DATA: 1001 case BSS: case ALIGN: case WGEN: case END: 1002 /* 1003 * Consider all pseudo-ops to be unique. 1004 */ 1005 return(0); 1006 } 1007 if (p1->op==MOVA && p1->labno!=p2->labno) return(0); 1008 cp1 = p1->code; 1009 cp2 = p2->code; 1010 if (cp1==0 && cp2==0) 1011 return(1); 1012 if (cp1==0 || cp2==0) 1013 return(0); 1014 while (*cp1 == *cp2++) 1015 if (*cp1++ == 0) 1016 return(1); 1017 return(0); 1018 } 1019 1020 #ifndef delnode 1021 delnode(p) register struct node *p; { 1022 p->back->forw = p->forw; 1023 p->forw->back = p->back; 1024 } 1025 #endif 1026 1027 #ifndef decref 1028 decref(p) 1029 register struct node *p; 1030 { 1031 if (p && --p->refc <= 0) { 1032 nrlab++; 1033 delnode(p); 1034 } 1035 } 1036 #endif 1037 1038 struct node * 1039 nonlab(ap) 1040 struct node *ap; 1041 { 1042 register struct node *p; 1043 1044 p = ap; 1045 while (p && p->op==LABEL) 1046 p = p->forw; 1047 return(p); 1048 } 1049 1050 clearuse() { 1051 register struct node **i; 1052 for (i=uses+NUSE; i>uses;) *--i=0; 1053 } 1054 1055 clearreg() { 1056 register char **i; 1057 for (i=regs; i<regs+NREG; ++i) { 1058 **i = 0; 1059 *(*i+1) = 0; 1060 } 1061 conloc[0] = 0; 1062 ccloc[0] = 0; 1063 } 1064 1065 savereg(ai, s, type) 1066 register char *s; 1067 { 1068 register char *p, *sp; 1069 1070 sp = p = regs[ai]; 1071 if (source(s)) /* side effects in addressing */ 1072 return; 1073 /* if any indexing, must be parameter or local */ 1074 /* indirection (as in "*-4(fp)") is ok, however */ 1075 *p++ = type; 1076 while (*p++ = *s) 1077 if (*s=='[' || *s++=='(' && *s!='a' && *s!='f') {*sp = 0; return;} 1078 } 1079 1080 dest(s,type) 1081 register char *s; 1082 { 1083 register int i; 1084 1085 (void) source(s); /* handle addressing side effects */ 1086 if (!natural(s)) { 1087 /* wild store, everything except constants vanishes */ 1088 for (i=NREG; --i>=0;) 1089 if (regs[i][1] != '$') 1090 regs[i][0] = regs[i][1] = 0; 1091 conloc[0] = 0; ccloc[0] = 0; 1092 return; 1093 } 1094 if ((i = isreg(s)) >= 0) { 1095 /* if register destination, that reg is a goner */ 1096 regs[i][0] = regs[i][1] = 0; 1097 switch(type & 0xF){ 1098 case DFLOAT: /* clobber two at once */ 1099 /*FALLTHROUGH*/ 1100 case GFLOAT: 1101 regs[i+1][0] = regs[i+1][1] = 0; 1102 break; 1103 case HFLOAT: /* clobber four at once */ 1104 regs[i+1][0] = regs[i+1][1] = 0; 1105 regs[i+2][0] = regs[i+2][1] = 0; 1106 regs[i+3][0] = regs[i+3][1] = 0; 1107 break; 1108 } 1109 switch((type>>4)&0xF){ 1110 case DFLOAT: /* clobber two at once */ 1111 /*FALLTHROUGH*/ 1112 case GFLOAT: 1113 regs[i+1][0] = regs[i+1][1] = 0; 1114 break; 1115 case HFLOAT: /* clobber four at once */ 1116 regs[i+1][0] = regs[i+1][1] = 0; 1117 regs[i+2][0] = regs[i+2][1] = 0; 1118 regs[i+3][0] = regs[i+3][1] = 0; 1119 break; 1120 } 1121 } 1122 for (i=NREG; --i>=0;) 1123 if (regs[i][1]=='*' && equstr(s, regs[i]+2)) 1124 regs[i][0] = regs[i][1] = 0; /* previous indirection through destination is invalid */ 1125 while ((i = findrand(s,0)) >= 0) /* previous values of destination are invalid */ 1126 regs[i][0] = regs[i][1] = 0; 1127 if (*conloc && equstr(conloc, s)) 1128 conloc[0] = 0; 1129 setcc(s, type); /* natural destinations set condition codes */ 1130 } 1131 1132 /* separate operands at commas, set up 'regs' and 'lastrand' */ 1133 splitrand(p) struct node *p; { 1134 register char *p1, *p2; 1135 register char **preg; 1136 1137 preg = regs+RT1; 1138 if (p1 = p->code) 1139 while (*p1) { 1140 lastrand = p2 = *preg++; 1141 while (*p1) 1142 if (',' == (*p2++ = *p1++)) { 1143 --p2; 1144 break; 1145 } 1146 *p2 = 0; 1147 } 1148 while (preg < (regs+RT1+5)) 1149 *(*preg++) = 0; 1150 } 1151 1152 compat(have, want) { 1153 register int hsrc, hdst; 1154 if (0==(want &= 0xF)) return(1); /* anything satisfies a wildcard want */ 1155 hsrc=have&0xF; 1156 if (0==(hdst=((have>>4)&0xF)) || (hdst>=OP2 && hdst<=OPX)) hdst=hsrc; 1157 if (want>=FFLOAT) return(hdst==want && hsrc==want); 1158 /* FLOAT, DFLOAT not compat: rounding */ 1159 return(hsrc>=want && hdst>=want && hdst<FFLOAT); 1160 } 1161 1162 equtype(t1,t2) {return(compat(t1,t2) && compat(t2,t1));} 1163 1164 findrand(as, type) 1165 char *as; 1166 { 1167 register char **i; 1168 for (i = regs+NREG; --i>=regs;) { 1169 if (**i && equstr(*i+1, as) && compat(**i,type)) 1170 return(i-regs); 1171 } 1172 return(-1); 1173 } 1174 1175 isreg(s) 1176 register char *s; 1177 { 1178 if (*s++!='r' || !isdigit(*s++)) return(-1); 1179 if (*s==0) return(*--s-'0'); 1180 if (*(s-1)=='1' && isdigit(*s++) && *s==0) return(10+*--s-'0'); 1181 return(-1); 1182 } 1183 1184 check() 1185 { 1186 register struct node *p, *lp; 1187 1188 lp = &first; 1189 for (p=first.forw; p!=0; p = p->forw) { 1190 if (p->back != lp) { 1191 fprintf(stderr, "c2: failed internal consistency check -- help!\n"); 1192 exit(-1); 1193 } 1194 lp = p; 1195 } 1196 } 1197 1198 source(ap) 1199 char *ap; 1200 { 1201 register char *p1, *p2; 1202 1203 p1 = ap; 1204 p2 = p1; 1205 if (*p1==0) 1206 return(0); 1207 while (*p2++ && *(p2-1)!='['); 1208 if (*p1=='-' && *(p1+1)=='(' 1209 || *p1=='*' && *(p1+1)=='-' && *(p1+2)=='(' 1210 || *(p2-2)=='+') { 1211 while (*p1 && *p1++!='r'); 1212 if (isdigit(*p1++)) 1213 if (isdigit(*p1)) 1214 regs[10+*p1-'0'][0] = regs[10+*p1-'0'][1] = 0; 1215 else { 1216 --p1; 1217 regs[*p1-'0'][0] = regs[*p1-'0'][1] = 0; 1218 } 1219 return(1); 1220 } 1221 return(0); 1222 } 1223 1224 newcode(p) struct node *p; { 1225 register char *p1,*p2,**preg; 1226 preg=regs+RT1; p2=line; 1227 while (*(p1= *preg++)) {while (*p2++= *p1++); *(p2-1)=',';} 1228 *--p2=0; 1229 p->code=copy(line); 1230 } 1231 1232 repladdr(p) 1233 struct node *p; 1234 { 1235 register r; 1236 register char *p1; 1237 char **preg; int nrepl; 1238 1239 preg=regs+RT1; nrepl=0; 1240 while (lastrand!=(p1= *preg++)) 1241 if (!source(p1) && 0<=(r=findrand(p1,p->subop))) { 1242 *p1++='r'; if (r>9) {*p1++='1'; r -= 10;} *p1++=r+'0'; *p1=0; 1243 nrepl++; nsaddr++; 1244 } 1245 if (nrepl) newcode(p); 1246 } 1247 1248 /* movedat() 1249 /* { 1250 /* register struct node *p1, *p2; 1251 /* struct node *p3; 1252 /* register seg; 1253 /* struct node data; 1254 /* struct node *datp; 1255 /* 1256 /* if (first.forw == 0) 1257 /* return; 1258 /* datp = &data; 1259 /* for (p1 = first.forw; p1!=0; p1 = p1->forw) { 1260 /* if (p1->op == DATA) { 1261 /* p2 = p1->forw; 1262 /* while (p2 && p2->op!=TEXT) 1263 /* p2 = p2->forw; 1264 /* if (p2==0) 1265 /* break; 1266 /* p3 = p1->back; 1267 /* p1->back->forw = p2->forw; 1268 /* p2->forw->back = p3; 1269 /* p2->forw = 0; 1270 /* datp->forw = p1; 1271 /* p1->back = datp; 1272 /* p1 = p3; 1273 /* datp = p2; 1274 /* } 1275 /* } 1276 /* if (data.forw) { 1277 /* datp->forw = first.forw; 1278 /* first.forw->back = datp; 1279 /* data.forw->back = &first; 1280 /* first.forw = data.forw; 1281 /* } 1282 /* seg = -1; 1283 /* for (p1 = first.forw; p1!=0; p1 = p1->forw) { 1284 /* if (p1->op==TEXT||p1->op==DATA||p1->op==BSS) { 1285 /* if (p1->op == seg || p1->forw&&p1->forw->op==seg) { 1286 /* p1->back->forw = p1->forw; 1287 /* p1->forw->back = p1->back; 1288 /* p1 = p1->back; 1289 /* continue; 1290 /* } 1291 /* seg = p1->op; 1292 /* } 1293 /* } 1294 /* } 1295 */ 1296 1297 redunbr(p) 1298 register struct node *p; 1299 { 1300 register struct node *p1; 1301 register char *ap1; 1302 char *ap2; 1303 1304 if ((p1 = p->ref) == 0) 1305 return; 1306 p1 = nonlab(p1); 1307 if (p1->op==TST) { 1308 splitrand(p1); 1309 savereg(RT2, "$0", p1->subop); 1310 } else if (p1->op==CMP) 1311 splitrand(p1); 1312 else 1313 return; 1314 if (p1->forw->op==CBR) { 1315 ap1 = findcon(RT1, p1->subop); 1316 ap2 = findcon(RT2, p1->subop); 1317 p1 = p1->forw; 1318 if (compare(p1->subop, ap1, ap2)) { 1319 nredunj++; 1320 nchange++; 1321 decref(p->ref); 1322 p->ref = p1->ref; 1323 p->labno = p1->labno; 1324 #ifdef COPYCODE 1325 if (p->labno == 0) 1326 p->code = p1->code; 1327 #endif 1328 if (p->ref) 1329 p->ref->refc++; 1330 } 1331 } else if (p1->op==TST && equstr(regs[RT1],ccloc+1) && 1332 equtype(ccloc[0],p1->subop)) { 1333 p1=insertl(p1->forw); decref(p->ref); p->ref=p1; 1334 nrtst++; nchange++; 1335 } 1336 } 1337 1338 char * 1339 findcon(i, type) 1340 { 1341 register char *p; 1342 register r; 1343 1344 p = regs[i]; 1345 if (*p=='$') 1346 return(p); 1347 if ((r = isreg(p)) >= 0 && compat(regs[r][0],type)) 1348 return(regs[r]+1); 1349 if (equstr(p, conloc)) 1350 return(conval+1); 1351 return(p); 1352 } 1353 1354 compare(opc, acp1, acp2) 1355 char *acp1, *acp2; 1356 { 1357 register char *cp1, *cp2; 1358 register n1; 1359 int n2; int sign; 1360 1361 cp1 = acp1; 1362 cp2 = acp2; 1363 if (*cp1++ != '$' || *cp2++ != '$') 1364 return(0); 1365 n1 = 0; sign=1; if (*cp2=='-') {++cp2; sign= -1;} 1366 while (isdigit(*cp2)) {n1 *= 10; n1 += (*cp2++ - '0')*sign;} 1367 n2 = n1; 1368 n1 = 0; sign=1; if (*cp1=='-') {++cp1; sign= -1;} 1369 while (isdigit(*cp1)) {n1 *= 10; n1 += (*cp1++ - '0')*sign;} 1370 if (*cp1=='+') 1371 cp1++; 1372 if (*cp2=='+') 1373 cp2++; 1374 do { 1375 if (*cp1++ != *cp2) 1376 return(0); 1377 } while (*cp2++); 1378 switch(opc) { 1379 1380 case JEQ: 1381 return(n1 == n2); 1382 case JNE: 1383 return(n1 != n2); 1384 case JLE: 1385 return(n1 <= n2); 1386 case JGE: 1387 return(n1 >= n2); 1388 case JLT: 1389 return(n1 < n2); 1390 case JGT: 1391 return(n1 > n2); 1392 case JLO: 1393 return((unsigned) n1 < (unsigned) n2); 1394 case JHI: 1395 return((unsigned) n1 > (unsigned) n2); 1396 case JLOS: 1397 return((unsigned) n1 <= (unsigned) n2); 1398 case JHIS: 1399 return((unsigned) n1 >= (unsigned) n2); 1400 } 1401 return(0); 1402 } 1403 1404 setcon(cv, cl, type) 1405 register char *cv, *cl; 1406 { 1407 register char *p; 1408 1409 if (*cv != '$') 1410 return; 1411 if (!natural(cl)) 1412 return; 1413 p = conloc; 1414 while (*p++ = *cl++); 1415 p = conval; 1416 *p++ = type; 1417 while (*p++ = *cv++); 1418 } 1419 1420 equstr(p1, p2) 1421 register char *p1, *p2; 1422 { 1423 do { 1424 if (*p1++ != *p2) 1425 return(0); 1426 } while (*p2++); 1427 return(1); 1428 } 1429 1430 setcc(ap,type) 1431 char *ap; 1432 { 1433 register char *p, *p1; 1434 1435 p = ap; 1436 if (!natural(p)) { 1437 ccloc[0] = 0; 1438 return; 1439 } 1440 p1 = ccloc; 1441 *p1++ = type; 1442 while (*p1++ = *p++); 1443 } 1444 1445 okio(p) register char *p; {/* 0->probable I/O space address; 1->not */ 1446 if (ioflag && (!natural(p) || 0>getnum(p))) return(0); 1447 return(1); 1448 } 1449 1450 indexa(p) register char *p; {/* 1-> uses [r] addressing mode; 0->doesn't */ 1451 while (*p) if (*p++=='[') return(1); 1452 return(0); 1453 } 1454 1455 natural(p) 1456 register char *p; 1457 {/* 1->simple local, parameter, global, or register; 0->otherwise */ 1458 if (*p=='*' || *p=='(' || *p=='-'&&p[1]=='(' || *p=='$'&&getnum(p+1)) 1459 return(0); 1460 while (*p++); 1461 p--; 1462 if (*--p=='+' || *p==']' || *p==')' && p[-2]!='a' && p[-2]!='f') 1463 return(0); 1464 return(1); 1465 } 1466 1467 /* 1468 ** Tell if an argument is most likely static. 1469 */ 1470 1471 isstatic(cp) 1472 register char *cp; 1473 { 1474 if (*cp == '_' || *cp == 'L' || (*cp++ == 'v' && *cp == '.')) 1475 return (1); 1476 return (0); 1477 } 1478 1479 autoid(p) register char *p; {/* 1-> uses autoincrement/autodecrement; 0->doesn't */ 1480 if (*p == '-' && *(p+1) == '(') return(1); 1481 while (*p) p++; 1482 if (*--p == '+' && *--p == ')') return(1); 1483 return(0); 1484 } 1485