void push_string (char * str) {
// push onto string stack
// save the label value into the offset field
ipush (strstack, str, UNKNOWN, 0, strlabelcount, REFERENCE);
// push onto operand stack - store offset in val field
ipush (inststack, NULL, STRING, strlabelcount, 0, IMMEDIATE);
// increment string label
strlabelcount++;
}
void generate_num2str () {
fprintf (fp, "\tpushl\t$12\n");
fprintf (fp, "\tcall\tmalloc\n");
fprintf (fp, "\taddl\t$4, %%esp\n");
fprintf (fp, "\tpushl\t$.LC%d\n", strlabelcount);
fprintf (fp, "\tpushl\t%%eax\n");
fprintf (fp, "\tcall\tsprintf\n");
fprintf (fp, "\tmovl\t0(%%esp), %%eax\n");
fprintf (fp, "\taddl\t$12, %%esp\n");
fprintf (fp, "\tpushl\t%%eax\n");
// write format integer string to strstack
ipush (strstack, "%d", UNKNOWN, 0, strlabelcount, REFERENCE);
strlabelcount++;
}
void push_fparam ( char * id, TYPE t, MEMTYPE mt, int val ) {
unsigned int offsetoverride = 0;
int valoverride = val;
// check for arithmetic result argument and mark stack position
if (mt == RESULT) {
param_spoffset += 4;
offsetoverride = param_spoffset;
} else if (mt == IMMEDIATE && t == STRING) {
valoverride = strlabelcount-1;
dump_operands (); // dump unused operands remaining in inststack
} else {
dump_operands ();
}
ipush (paramstack, id, t, valoverride, offsetoverride, mt);
}
void push_operand ( char * id, int val, MEMTYPE m ) {
node * temp;
TYPE tt;
// check if this is a FOR loop condition
if (sts->current_scope->loopBegLabel > 0 && !suppressIter) {
//fprintf (fp, "set for iteration\n");
generate_for_iter_inst ();
suppressIter = 1;
}
// if we're pushing an id then we need to lookup in the symtab
if (m == REFERENCE) {
if ( (temp = lookup (sts, id)) == NULL )
error_handler(UNDECLARED_ID_ERROR, id);
tt = temp->t;
} else {
tt = INT;
}
// push operand onto instruction stack
ipush (inststack, id, tt, val, 0, m);
}
void push_back_global ( char * id ) {
// push on global declaration stack
ipush (globstack, id, UNKNOWN, 0, 0, REFERENCE);
}
void
parse(char *f, int fd, int varoverride)
{
int hline;
char *body;
Word *head, *tail;
int attr, set, pid;
char *prog, *p;
int newfd;
Biobuf in;
Bufblock *buf;
if(fd < 0) {
perror(f);
Exit();
}
ipush();
infile = strdup(f);
mkinline = 1;
Binit(&in, fd, OREAD);
buf = newbuf();
while(assline(&in, buf)) {
hline = mkinline;
switch(rhead(buf->start, &head, &tail, &attr, &prog))
{
case '<':
p = wtos(tail, ' ');
if(*p == 0) {
SYNERR(-1);
fprint(2, "missing include file name\n");
Exit();
}
newfd = open(p, OREAD);
if(newfd < 0) {
fprint(2, "warning: skipping missing include file: ");
perror(p);
} else
parse(p, newfd, 0);
break;
case '|':
p = wtos(tail, ' ');
if(*p == 0) {
SYNERR(-1);
fprint(2, "missing include program name\n");
Exit();
}
execinit();
pid=pipecmd(p, envy, &newfd);
if(newfd < 0) {
fprint(2, "warning: skipping missing program file: ");
perror(p);
} else
parse(p, newfd, 0);
while(waitup(-3, &pid) >= 0)
;
if(pid != 0) {
fprint(2, "bad include program status\n");
Exit();
}
break;
case ':':
body = rbody(&in);
addrules(head, tail, body, attr, hline, prog);
break;
case '=':
if(head->next) {
SYNERR(-1);
fprint(2, "multiple vars on left side of assignment\n");
Exit();
}
if(symlook(head->s, S_OVERRIDE, 0)) {
set = varoverride;
} else {
set = 1;
if(varoverride)
symlook(head->s, S_OVERRIDE, (void *)"");
}
if(set) {
/*
char *cp;
dumpw("tail", tail);
cp = wtos(tail, ' '); print("assign %s to %s\n", head->s, cp); free(cp);
*/
setvar(head->s, (void *) tail);
symlook(head->s, S_WESET, (void *)"");
}
if(attr)
symlook(head->s, S_NOEXPORT, (void *)"");
break;
default:
SYNERR(hline);
fprint(2, "expected one of :<=\n");
Exit();
break;
}
}
close(fd);
freebuf(buf);
ipop();
}
