1 #ifndef lint 2 static char sccsid[] = "@(#)c21.c 4.19 04/27/86"; 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 } 1477