void
label_union (Label *a, Label *b)
{
Label *root_a, *root_b;
root_a = label_find (a);
root_b = label_find (b);
if (root_a->index < root_b->index)
{
b->parent = root_a;
}
else
{
a->parent = root_b;
}
}
/* NOTE: the same name space as C labels is used to avoid using too
much memory when storing labels in TokenStrings */
static void asm_new_label1(TCCState *s1, int label, int is_local,
int sh_num, int value)
{
Sym *sym;
sym = label_find(label);
if (sym) {
if (sym->r) {
/* the label is already defined */
if (!is_local) {
tcc_error("assembler label '%s' already defined",
get_tok_str(label, NULL));
} else {
/* redefinition of local labels is possible */
goto new_label;
}
}
} else {
new_label:
sym = label_push(&s1->asm_labels, label, 0);
sym->type.t = VT_STATIC | VT_VOID;
}
sym->r = sh_num;
sym->jnext = value;
}
Label *
label_find (Label *label)
{
Label *parent;
g_return_val_if_fail (label != NULL, NULL);
parent = label->parent;
if (parent == label)
return parent;
else
return label_find (parent);
}
static void asm_expr_unary(TCCState *s1, ExprValue *pe)
{
Sym *sym;
int op, n, label;
const char *p;
switch(tok) {
case TOK_PPNUM:
p = tokc.cstr->data;
n = strtoul(p, (char **)&p, 0);
if (*p == 'b' || *p == 'f') {
/* backward or forward label */
label = asm_get_local_label_name(s1, n);
sym = label_find(label);
if (*p == 'b') {
/* backward : find the last corresponding defined label */
if (sym && sym->r == 0)
sym = sym->prev_tok;
if (!sym)
tcc_error("local label '%d' not found backward", n);
} else {
/* forward */
if (!sym || sym->r) {
/* if the last label is defined, then define a new one */
sym = label_push(&s1->asm_labels, label, 0);
sym->type.t = VT_STATIC | VT_VOID;
}
}
pe->v = 0;
pe->sym = sym;
} else if (*p == '\0') {
pe->v = n;
pe->sym = NULL;
} else {
tcc_error("invalid number syntax");
}
next();
break;
case '+':
next();
asm_expr_unary(s1, pe);
break;
case '-':
case '~':
op = tok;
next();
asm_expr_unary(s1, pe);
if (pe->sym)
tcc_error("invalid operation with label");
if (op == '-')
pe->v = -pe->v;
else
pe->v = ~pe->v;
break;
case TOK_CCHAR:
case TOK_LCHAR:
pe->v = tokc.i;
pe->sym = NULL;
next();
break;
case '(':
next();
asm_expr(s1, pe);
skip(')');
break;
default:
if (tok >= TOK_IDENT) {
/* label case : if the label was not found, add one */
sym = label_find(tok);
if (!sym) {
sym = label_push(&s1->asm_labels, tok, 0);
/* NOTE: by default, the symbol is global */
sym->type.t = VT_VOID;
}
if (sym->r == SHN_ABS) {
/* if absolute symbol, no need to put a symbol value */
pe->v = sym->jnext;
pe->sym = NULL;
} else {
pe->v = 0;
pe->sym = sym;
}
next();
} else {
tcc_error("bad expression syntax [%s]", get_tok_str(tok, &tokc));
}
break;
}
}
