legacy-cc/last1120c/c00.c
2013-03-01 08:05:32 -06:00

582 lines
8.3 KiB
C

/* C compiler
Copyright 1972 Bell Telephone Laboratories, Inc.
*/
ossiz 250;
ospace() {} /* fake */
init(s, t)
char s[]; {
extern lookup, symbuf, namsiz;
char symbuf[], sp[];
int np[], i;
i = namsiz;
sp = symbuf;
while(i--)
if ((*sp++ = *s++)=='\0') --s;
np = lookup();
*np++ = 1;
*np = t;
}
main(argc, argv)
int argv[]; {
extern init, flush;
extern extdef, eof, open, creat;
extern fout, fin, error, exit, nerror, tmpfil;
if(argc<4) {
error("Arg count");
exit(1);
}
if((fin=open(argv[1],0))<0) {
error("Can't find %s", argv[1]);
exit(1);
}
if((fout=creat(argv[2], 017))<0) {
error("Can't create %s", argv[2]);
exit(1);
}
tmpfil = argv[3];
init("int", 0);
init("char", 1);
init("float", 2);
init("double", 3);
/* init("long", 4); */
init("auto", 5);
init("extern", 6);
init("static", 7);
init("goto", 10);
init("return", 11);
init("if", 12);
init("while", 13);
init("else", 14);
init("switch", 15);
init("case", 16);
init("break", 17);
init("continue", 18);
init("do", 19);
init("default", 20);
while(!eof) {
extdef();
blkend();
}
flush();
flshw();
exit(nerror!=0);
}
lookup() {
extern hshtab[], hshsiz, pssiz, symbuf[];
extern hshlen, hshused, exit, error, nwps;
auto i, j, np[], sp[], rp[];
i = 0;
sp = symbuf;
j = nwps;
while(j--)
i =+ *sp++;
if (i<0) i = -i;
i =% hshsiz;
i =* pssiz;
while(*(np = &hshtab[i+4])) {
sp = symbuf;
j = nwps;
while(j--)
if (*np++ != *sp++) goto no;
return(&hshtab[i]);
no: if ((i =+ pssiz) >= hshlen) i = 0;
}
if(hshused++ > hshsiz) {
error("Symbol table overflow");
exit(1);
}
rp = np = &hshtab[i];
sp = symbuf;
j = 4;
while(j--)
*np++ = 0;
j = nwps;
while(j--)
*np++ = *sp++;
return(rp);
}
symbol() {
extern peeksym, peekc, eof, getchar, subseq, error, line;
extern csym[], getstr, symbuf, namsiz, lookup[], ctab, cval;
auto b, c;
char symbuf[], sp[], ctab[];
if (peeksym>=0) {
c = peeksym;
peeksym = -1;
return(c);
}
if (peekc) {
c = peekc;
peekc = 0;
} else
if (eof)
return(0); else
c = getchar();
loop:
switch(ctab[c]) {
case 125: /* newline */
line++;
case 126: /* white space */
c = getchar();
goto loop;
case 0: /* EOF */
eof++;
return(0);
case 40: /* + */
return(subseq(c,40,30));
case 41: /* - */
return(subseq(c,41,31));
case 80: /* = */
if (subseq(' ',0,1)) return(80);
c = symbol();
if (c>=40 & c<=49)
return(c+30);
if (c==80)
return(60);
peeksym = c;
return(80);
case 63: /* < */
if (subseq(c,0,1)) return(46);
return(subseq('=',63,62));
case 65: /* > */
if (subseq(c,0,1)) return(45);
return(subseq('=',65,64));
case 34: /* ! */
return(subseq('=',34,61));
case 43: /* / */
if (subseq('*',1,0))
return(43);
com:
c = getchar();
com1:
if (c=='\0') {
eof++;
error("Nonterminated comment");
return(0);
}
if (c=='\n')
line++;
if (c!='*')
goto com;
c = getchar();
if (c!='/')
goto com1;
c = getchar();
goto loop;
case 124: /* number */
cval = 0;
if (c=='0')
b = 8; else
b = 10;
while(ctab[c]==124) {
cval = cval*b + c -'0';
c = getchar();
}
peekc = c;
return(21);
case 122: /* " */
return(getstr());
case 121: /* ' */
return(getcc());
case 123: /* letter */
sp = symbuf;
while(ctab[c]==123 | ctab[c]==124) {
if (sp<symbuf+namsiz) *sp++ = c;
c = getchar();
}
while(sp<symbuf+namsiz)
*sp++ = '\0';
peekc = c;
csym = lookup();
if (csym[0]==1) { /* keyword */
cval = csym[1];
return(19);
}
return(20);
case 127: /* unknown */
error("Unknown character");
c = getchar();
goto loop;
}
return(ctab[c]);
}
subseq(c,a,b) {
extern getchar, peekc;
if (!peekc)
peekc = getchar();
if (peekc != c)
return(a);
peekc = 0;
return(b);
}
getstr() {
extern isn, cval;
auto c;
printf(".data;L%d:.byte ", cval=isn++);
while((c=mapch('"')) >= 0)
printf("%o,", c);
printf("0;.even;.text\n");
return(22);
}
getcc()
{
extern cval, ncpw;
auto c, cc;
char cp[];
cval = 0;
cp = &cval;
cc = 0;
while((c=mapch('\'')) >= 0)
if(cc++ < ncpw)
*cp++ = c;
if(cc>ncpw)
error("Long character constant");
return(21);
}
mapch(c)
{
extern peekc, line;
auto a;
if((a=getchar())==c)
return(-1);
switch(a) {
case '\n':
case 0:
error("Nonterminated string");
peekc = a;
return(-1);
case '\\':
switch (a=getchar()) {
case 't':
return('\t');
case 'n':
return('\n');
case '0':
return('\0');
case 'r':
return('\r');
case '\n':
line++;
return('\n');
}
}
return(a);
}
tree() {
extern symbol, block, csym[], ctyp, isn,
peeksym, opdope[], build, error, cp[], cmst[],
space, ospace, cval, ossiz, exit, errflush, cmsiz;
auto op[], opst[20], pp[], prst[20], andflg, o,
p, ps, os;
space = ospace;
op = opst;
pp = prst;
cp = cmst;
*op = 200; /* stack EOF */
*pp = 06;
andflg = 0;
advanc:
switch (o=symbol()) {
/* name */
case 20:
if (*csym==0)
if((peeksym=symbol())==6)
*csym = 6; /* extern */
else {
if(csym[2]==0) /* unseen so far */
csym[2] = isn++;
}
if(*csym==6) /* extern */
*cp++ = block(5,20,csym[1],0,*csym,
csym[4],csym[5],csym[6],csym[7]);
else
*cp++ = block(2,20,csym[1],0,*csym,csym[2]);
goto tand;
/* short constant */
case 21:
case21:
*cp++ = block(1,21,ctyp,0,cval);
goto tand;
/* string constant */
case 22:
*cp++ = block(1,22,17,0,cval);
tand:
if(cp>=cmst+cmsiz) {
error("Expression overflow");
exit(1);
}
if (andflg)
goto syntax;
andflg = 1;
goto advanc;
/* ++, -- */
case 30:
case 31:
if (andflg)
o =+ 2;
goto oponst;
/* ! */
case 34:
if (andflg)
goto syntax;
goto oponst;
/* - */
case 41:
if (!andflg) {
peeksym = symbol();
if (peeksym==21) {
peeksym = -1;
cval = -cval;
goto case21;
}
o = 37;
}
andflg = 0;
goto oponst;
/* & */
/* * */
case 47:
case 42:
if (andflg)
andflg = 0; else
if(o==47)
o = 35;
else
o = 36;
goto oponst;
/* ( */
case 6:
if (andflg) {
o = symbol();
if (o==7)
o = 101; else {
peeksym = o;
o = 100;
andflg = 0;
}
}
goto oponst;
/* ) */
/* ] */
case 5:
case 7:
if (!andflg)
goto syntax;
goto oponst;
}
/* binaries */
if (!andflg)
goto syntax;
andflg = 0;
oponst:
p = (opdope[o]>>9) & 077;
opon1:
ps = *pp;
if (p>ps | p==ps & (opdope[o]&0200)!=0) { /* right-assoc */
putin:
switch (o) {
case 6: /* ( */
case 4: /* [ */
case 100: /* call */
p = 04;
}
if(op>=opst+20) { /* opstack size */
error("expression overflow");
exit(1);
}
*++op = o;
*++pp = p;
goto advanc;
}
--pp;
switch (os = *op--) {
/* EOF */
case 200:
peeksym = o;
return(*--cp);
/* call */
case 100:
if (o!=7)
goto syntax;
build(os);
goto advanc;
/* mcall */
case 101:
*cp++ = 0; /* 0 arg call */
os = 100;
goto fbuild;
/* ( */
case 6:
if (o!=7)
goto syntax;
goto advanc;
/* [ */
case 4:
if (o!=5)
goto syntax;
build(4);
goto advanc;
}
fbuild:
build(os);
goto opon1;
syntax:
error("Expression syntax");
errflush(o);
return(0);
}
declare(kw) {
extern csym[], symbol, paraml[], parame[];
extern error, cval, errflush, peeksym, exit;
int t[], n, o;
while((o=symbol())==20) { /* name */
if(kw>=5) { /* type or sort? */
if(*csym>0)
error("%p redeclared", csym[4]);
*csym = kw;
} else {
if ((csym[1]&017)!=0)
error("%p redeclared", &csym[4]);
csym[1] =| csym[1]&0760 | kw;
if (*csym==0)
*csym = -2;
}
while((o=symbol())==4) { /* [ */
if((o=symbol())==21) { /* const */
if(csym[1]>=020)
error("Bad vector");
csym[3] = cval;
o = symbol();
}
if (o!=5) /* ] */
goto syntax;
csym[1] =+ 020;
}
if(kw==8) { /* parameter */
*csym = -1;
if (paraml==0)
paraml = csym;
else
*parame = csym;
parame = csym;
}
if (o!=9) /* , */
break;
}
if(o==1 & kw!=8 | o==7 & kw==8)
return;
syntax:
error("Declaration syntax");
errflush(o);
}
/* storage */
regtab 0;
efftab 1;
cctab 2;
sptab 3;
symbuf[4];
pssiz 8;
namsiz 8;
nwps 4;
hshused 0;
hshsiz 100;
hshlen 800; /* 8*hshsiz */
hshtab[800];
space 0;
cp 0;
cmsiz 40;
cmst[40];
ctyp 0;
isn 1;
swsiz 120;
swtab[120];
swp 0;
contlab 0;
brklab 0;
deflab 0;
nreg 4;
maprel[] 60,61,64,65,62,63,68,69,66,67;
nauto 0;
stack 0;
peeksym 0177777;
peekc 0;
eof 0;
line 1;
csym 0;
cval 0;
ncpw 2;
nerror 0;
paraml;
parame;
tmpfil;