NODE *
funarg(NODE *p, int *n)
{
NODE *r;
int sz;
if (p->n_op == CM) {
p->n_left = funarg(p->n_left, n);
p->n_right = funarg(p->n_right, n);
return p;
}
sz = szty(p->n_type);
if (*n % sz)
(*n)++; /* XXX LDOUBLE */
if (*n >= 4) {
*n += sz;
r = block(OREG, NIL, NIL, p->n_type|PTR, 0, 0);
r->n_rval = SP;
r->n_lval = -(32 + *n * 4);
} else {
r = block(REG, NIL, NIL, p->n_type, 0, 0);
r->n_lval = 0;
r->n_rval = argreg(p->n_type, n);
}
p = block(ASSIGN, r, p, p->n_type, 0, 0);
clocal(p);
return p;
}
/*
* code for the beginning of a function; 'a' is an array of
* indices in symtab for the arguments; n is the number
*/
void
bfcode(struct symtab **a, int cnt)
{
struct symtab *sp;
NODE *p, *q;
int i, n, sz;
if (cftnsp->stype == STRTY+FTN || cftnsp->stype == UNIONTY+FTN) {
/* Function returns struct, adjust arg offset */
for (i = 0; i < n; i++)
a[i]->soffset += SZPOINT(LONG);
}
/* recalculate the arg offset and create TEMP moves */
for (n = 0, i = 0; i < cnt; i++) {
sp = a[i];
sz = szty(sp->stype);
if (n % sz)
n++; /* XXX LDOUBLE */
if (n < 4) {
p = tempnode(0, sp->stype, sp->sdf, sp->ssue);
/* TODO p->n_left->n_lval = -(32 + n * 4); */
q = block(REG, NIL, NIL, sp->stype, sp->sdf, sp->ssue);
q->n_rval = argreg(sp->stype, &n);
p = buildtree(ASSIGN, p, q);
sp->soffset = regno(p->n_left);
sp->sflags |= STNODE;
ecomp(p);
} else {
sp->soffset += SZINT * n;
if (xtemps) {
/* put stack args in temps if optimizing */
p = tempnode(0, sp->stype, sp->sdf, sp->ssue);
p = buildtree(ASSIGN, p, buildtree(NAME, 0, 0));
sp->soffset = regno(p->n_left);
sp->sflags |= STNODE;
ecomp(p);
}
}
}
}
//function(..) module saved jan 1 2013 as part of prep for scrt integration
static void function(Symbol f, Symbol caller[], Symbol callee[], int ncalls) {
int i, saved, sizefsave, sizeisave, varargs;
Symbol r, argregs[NUM_ARG_REGS];
usedmask[0] = usedmask[1] = 0;
freemask[0] = freemask[1] = ~(unsigned)0;
offset = maxoffset = maxargoffset = 0;
for (i = 0; callee[i]; i++) //find last argument
;
varargs = variadic(f->type) //see if variable arguments by type or by name of final argument
|| i > 0 && strcmp(callee[i-1]->name, "va_alist") == 0;
for (i = 0; callee[i]; i++) { //for each argument
Symbol p = callee[i];
Symbol q = caller[i];
assert(q);
offset = roundup(offset, q->type->align); //calculate the offset from the caller's sp
p->x.offset = q->x.offset = offset;
p->x.name = q->x.name = stringd(offset);
r = argreg(i, offset, optype(ttob(q->type)), q->type->size, optype(ttob(caller[0]->type)));
if (i < NUM_ARG_REGS)
argregs[i] = r;
offset = roundup(offset + q->type->size, 2); //i dunno
if (varargs)
p->sclass = AUTO; //variable args are always auto?
else if (r && ncalls == 0 && //I dunno
!isstruct(q->type) && !p->addressed &&
!(isfloat(q->type) && r->x.regnode->set == IREG)) {
p->sclass = q->sclass = REGISTER;
askregvar(p, r);
assert(p->x.regnode && p->x.regnode->vbl == p);
q->x = p->x;
q->type = p->type;
}
else if (askregvar(p, rmap(ttob(p->type)))
&& r != NULL
&& (isint(p->type) || p->type == q->type)) {
assert(q->sclass != REGISTER);
p->sclass = q->sclass = REGISTER;
q->type = p->type;
}
}
assert(!caller[i]); //done with arguments, their individual offsets and maxargoffset have been set
offset = 0;
gencode(caller, callee);
if (ncalls) //prepare to save return address if necessary(i.e. we do calls of our own)
usedmask[IREG] |= ((unsigned)1)<<REG_RETADDR;
usedmask[IREG] &= INT_CALLEE_SAVE; //limit saving to those we're responsible for
usedmask[FREG] &= 0xfff00000;
maxargoffset = roundup(maxargoffset, usedmask[FREG] ? 8 : 2);
if (ncalls && maxargoffset < NUM_ARG_REGS*2)
maxargoffset = NUM_ARG_REGS*2;
sizefsave = 4*bitcount(usedmask[FREG]); //space needed to save the float regs
sizeisave = 2*bitcount(usedmask[IREG]); //space needed to save the int regs
framesize = roundup(maxargoffset + sizefsave //space for outgoing arguments, space for saving floats,
+ sizeisave + maxoffset, 2); //space for saving ints, space for locals
//segment(CODE);
//printf("\talign 16\n");
printf("%s:\n", f->x.name);
i = maxargoffset + sizefsave - framesize; //I dunno but it's -v and it's never used!
if (framesize > 0)
print("\talu2I sp,sp,%d,smi,smbi\n", framesize);
saved = maxargoffset;
/space needed for outgoing arguments
