# /* * C compiler */ #include "c1h.c" max(a, b) { if (a>b) return(a); return(b); } degree(at) struct tnode *at; { register struct tnode *t; if ((t=at)==0 || t->op==0) return(0); if (t->op==CON || t->op==SFCON) return(-3); if (t->op == AMPER) return(-2); if ((opdope[t->op] & LEAF) != 0) { if (t->type==CHAR || t->type==FLOAT) return(1); return(0); } return(t->degree); } pname(ap, flag) struct tnode *ap; { register i; register struct tnode *p; p = ap; loop: switch(p->op) { case SFCON: case CON: printf("$%o", p->value); return; case FCON: printf("L%d", p->value); return; case NAME: if (i = p->offset) { psoct(i); if (p->class!=OFFS) putchar('+'); } switch(p->class) { case SOFFS: case XOFFS: pbase(p); case OFFS: printf("(r%d)", p->regno); return; case EXTERN: case STATIC: pbase(p); return; case REG: printf("r%d", p->nloc); return; } error("Compiler error: pname"); return; case AMPER: putchar('$'); p = p->tr1; goto loop; case AUTOI: printf("(r%d)%c", p->nloc, flag?0:'+'); return; case AUTOD: printf("%c(r%d)", flag?0:'-', p->nloc); return; case STAR: p = p->tr1; putchar('*'); goto loop; } error("pname called illegally"); } pbase(ap) struct tnode *ap; { register struct tnode *p; p = ap; if (p->class==SOFFS || p->class==STATIC) printf("L%d", p->nloc); else printf("_%.8s", &(p->nloc)); } xdcalc(ap, nrleft) struct tnode *ap; { register struct tnode *p; register d; p = ap; d = dcalc(p, nrleft); if (d<20 && p->type==CHAR) { if (nrleft>=1) d = 20; else d = 24; } return(d); } dcalc(ap, nrleft) struct tnode *ap; { register struct tnode *p, *p1; if ((p=ap)==0) return(0); switch (p->op) { case NAME: if (p->class==REG) return(9); case AMPER: case FCON: case AUTOI: case AUTOD: return(12); case CON: case SFCON: return(p->value==0? 4:(p->value==1?5:8)); case STAR: p1 = p->tr1; if (p1->op==NAME || p1->op==CON) return(12); } return(p->degree<=nrleft? 20: 24); } notcompat(ap, ast, op) struct tnode *ap; { register at, st; register struct tnode *p; p = ap; at = p->type; st = ast; if ((at&07)==STRUCT) at =& 077770; /* map to int */ if (st==0) /* word, byte */ return(at>1 & at<=07); if (st==1) /* word */ return(at>0 & at<=07); st =- 2; if ((at&077740) != 0) at = 020; if ((at&077770) != 0) at = at&07 | 020; if (st==2 && at==3) at = 2; if (p->op==NAME && p->class==REG && op==ASSIGN && st==CHAR) return(0); return(st != at); } prins(op, c) { register struct instab *insp; register char *ip; for (insp=instab; insp->op != 0; insp++) { if (insp->op == op) { ip = c? insp->str2: insp->str1; if (ip==0) break; printf("%s", ip); return; } } error("No match' for op %d", op); } collcon(ap) struct tnode *ap; { register op; register struct tnode *p; p = ap; if (p->op==STAR) p = p->tr1; if (p->op==PLUS) { op = p->tr2->op; if (op==CON || op==AMPER) return(1); } return(0); } isfloat(at) struct tnode *at; { register struct tnode *t; t = at; if ((opdope[t->op]&RELAT)!=0) t = t->tr1; if (t->type==FLOAT || t->type==DOUBLE) { nfloat = 1; return('f'); } return(0); } oddreg(t, areg) struct tnode *t; { register reg; reg = areg; if (!isfloat(t)) switch(t->op) { case DIVIDE: case MOD: case ASDIV: case ASMOD: reg++; case TIMES: case ASTIMES: return(reg|1); } return(reg); } arlength(t) { if (t>=PTR) return(2); switch(t) { case INT: case CHAR: return(2); case FLOAT: case DOUBLE: return(8); } return(1024); } pswitch(afp, alp, deflab) struct swtab *afp, *alp; { int tlab, ncase, i, j, tabs, worst, best, range; register struct swtab *swp, *fp, *lp; int poctab[swsiz]; fp = afp; lp = alp; if (fp==lp) { printf("jbr L%d\n", deflab); return; } tlab = isn++; if (sort(fp, lp)) return; ncase = lp-fp; lp--; range = lp->swval - fp->swval; /* direct switch */ if (range>0 && range <= 3*ncase) { if (fp->swval) printf("sub $%o,r0\n", fp->swval); printf("cmp r0,$%o\n", range); printf("jhi L%d\n", deflab); printf("asl r0\n"); printf("jmp *L%d(r0)\n.data\nL%d:", isn, isn); isn++; for (i=fp->swval; i<=lp->swval; i++) { if (i==fp->swval) { printf("L%d\n", fp->swlab); fp++; } else printf("L%d\n", deflab); } goto esw; } /* simple switch */ if (ncase<8) { i = isn++; j = isn++; printf("mov $L%d,r1\n", i); printf("mov r0,L%d\n", j); printf("L%d:cmp r0,(r1)+\n", isn); printf("jne L%d\n", isn++); printf("jmp *L%d-L%d(r1)\n", j, i); printf(".data\nL%d:", i); for (; fp<=lp; fp++) printf("%o\n", fp->swval); printf("L%d:..\n", j); for (fp = afp; fp<=lp; fp++) printf("L%d\n", fp->swlab); printf("L%d\n", deflab); goto esw; } /* hash switch */ best = 077777; for (i=ncase/4; i<=ncase/2; i++) { for (j=0; j<i; j++) poctab[j] = 0; for (swp=fp; swp<=lp; swp++) poctab[lrem(0, swp->swval, i)]++; worst = 0; for (j=0; j<i; j++) if (poctab[j]>worst) worst = poctab[j]; if (i*worst < best) { tabs = i; best = i*worst; } } printf("jsr r2,hsw; %o; L%d\n", tabs, isn); printf("jmp *L%d-L%d(r1)\n", isn+tabs+1, isn+1); printf(".data\nL%d:", isn++); for (i=0; i<=tabs; i++) printf("L%d\n", isn+i); for (i=0; i<tabs; i++) { printf("L%d:..\n", isn++); for (swp=fp; swp<=lp; swp++) if (lrem(0, swp->swval, tabs) == i) printf("%o\n", ldiv(0, swp->swval, tabs)); } printf("L%d:", isn++); for (i=0; i<tabs; i++) { printf("L%d\n", deflab); for (swp=fp; swp<=lp; swp++) if (lrem(0, swp->swval, tabs) == i) printf("L%d\n", swp->swlab); } esw: printf(".text\n"); } sort(afp, alp) struct swtab *afp, *alp; { register struct swtab *cp, *fp, *lp; int intch, t; fp = afp; lp = alp; while (fp < --lp) { intch = 0; for (cp=fp; cp<lp; cp++) { if (cp->swval == cp[1].swval) { error("Duplicate case (%d)", cp->swval); return(1); } if (cp->swval > cp[1].swval) { intch++; t = cp->swval; cp->swval = cp[1].swval; cp[1].swval = t; t = cp->swlab; cp->swlab = cp[1].swlab; cp[1].swlab = t; } } if (intch==0) break; } return(0); } ispow2(atree) { register int d; register struct tnode *tree; tree = atree; if (!isfloat(tree) && tree->tr2->op==CON) { d = tree->tr2->value; if (d>1 && (d&(d-1))==0) return(d); } return(0); } pow2(atree) struct tnode *atree; { register int d, i; register struct tnode *tree; tree = atree; if (d = ispow2(tree)) { for (i=0; (d=>>1)!=0; i++); tree->tr2->value = i; d = tree->op; tree->op = d==TIMES? LSHIFT: (d==DIVIDE? RSHIFT: (d==ASTIMES? ASLSH: ASRSH)); } } cbranch(atree, albl, cond, areg) struct tnode *atree; { int l1, op; register lbl, reg; register struct tnode *tree; lbl = albl; reg = areg; if ((tree=atree)==0) return; switch(tree->op) { case LOGAND: if (cond) { cbranch(tree->tr1, l1=isn++, 0, reg); cbranch(tree->tr2, lbl, 1, reg); label(l1); } else { cbranch(tree->tr1, lbl, 0, reg); cbranch(tree->tr2, lbl, 0, reg); } return; case LOGOR: if (cond) { cbranch(tree->tr1, lbl, 1, reg); cbranch(tree->tr2, lbl, 1, reg); } else { cbranch(tree->tr1, l1=isn++, 1, reg); cbranch(tree->tr2, lbl, 0, reg); label(l1); } return; case EXCLA: cbranch(tree->tr1, lbl, !cond, reg); return; case COMMA: rcexpr(tree->tr1, efftab, reg); tree = tree->tr2; break; } rcexpr(tree, cctab, reg); op = tree->op; if ((opdope[op]&RELAT)==0) op = NEQUAL; else if (tree->tr2->op==CON && tree->tr2->value==0) op =+ 200; /* special for ptr tests */ if (isfloat(tree)) printf("cfcc\n"); branch(lbl, op, !cond); } branch(lbl, aop, c) { register op; if(op=aop) prins(op,c); else printf("jbr"); printf("\tL%d\n", lbl); } label(l) { printf("L%d:", l); } popstk(a) { switch(a) { case 0: return; case 2: printf("tst (sp)+\n"); return; case 4: printf("cmp (sp)+,(sp)+\n"); return; } printf("add $%o,sp\n", a); } error(s, p1, p2, p3, p4, p5, p6) { register f; extern fout; nerror++; flush(); f = fout; fout = 1; printf("%d: ", line); printf(s, p1, p2, p3, p4, p5, p6); putchar('\n'); flush(); fout = f; } psoct(an) { register int n, sign; sign = 0; if ((n = an) < 0) { n = -n; sign = '-'; } printf("%c%o", sign, n); }