static void traverse_decl(ast_decl_t decl)
{
switch (decl->kind)
{
case AST_FUNCS_DECL: {
list_t p = decl->u.funcs;
for (; p; p = p->next)
{
ast_func_t func = p->data;
list_t q;
_depth++;
sym_begin_scope(_env);
for (q = func->params; q; q = q->next)
{
ast_field_t field = q->data;
sym_enter(_env,
field->name,
escape_entry(_depth, &field->escape));
}
traverse_expr(func->body);
sym_end_scope(_env);
_depth--;
}
break;
}
case AST_TYPES_DECL:
break;
case AST_VAR_DECL:
sym_enter(_env,
decl->u.var.var,
escape_entry(_depth, &decl->u.var.escape));
traverse_expr(decl->u.var.init);
break;
}
}
void traverse_exprls(expr_t *exprls,int postorder,void (*e) (expr_t *)) {
expr_t *next;
DB1(70,"{traverse_exprls(,%d,);\n",postorder);
if (e == NULL) {
DB1(75,"}returning from traverse_exprls(,%d,);\n",postorder);
return;
}
for (; exprls != NULL; exprls = next) {
next = T_NEXT(exprls);
traverse_expr(exprls,postorder,e);
}
DB1(75,"}returning from traverse_exprls(,%d,);\n",postorder);
}
static void traverse_var(ast_var_t var)
{
switch (var->kind)
{
case AST_SIMPLE_VAR: {
escape_entry_t entry = sym_lookup(_env, var->u.simple);
if (entry && entry->depth < _depth)
*entry->escape = true;
break;
}
case AST_FIELD_VAR:
traverse_var(var->u.field.var);
break;
case AST_SUB_VAR:
traverse_var(var->u.sub.var);
traverse_expr(var->u.sub.sub);
break;
}
}
static void traverse_expr(ast_expr_t expr)
{
list_t p;
switch (expr->kind)
{
case AST_NIL_EXPR:
break;
case AST_VAR_EXPR:
traverse_var(expr->u.var);
break;
case AST_NUM_EXPR:
case AST_STRING_EXPR:
break;
case AST_CALL_EXPR:
for (p = expr->u.call.args; p; p = p->next)
traverse_expr(p->data);
break;
case AST_OP_EXPR:
traverse_expr(expr->u.op.left);
traverse_expr(expr->u.op.right);
break;
case AST_RECORD_EXPR:
for (p = expr->u.record.efields; p; p = p->next)
traverse_expr(((ast_efield_t) p->data)->expr);
break;
case AST_ARRAY_EXPR:
traverse_expr(expr->u.array.size);
traverse_expr(expr->u.array.init);
break;
case AST_SEQ_EXPR:
for (p = expr->u.seq; p; p = p->next)
traverse_expr(p->data);
break;
case AST_IF_EXPR:
traverse_expr(expr->u.if_.cond);
traverse_expr(expr->u.if_.then);
if (expr->u.if_.else_)
traverse_expr(expr->u.if_.else_);
break;
case AST_WHILE_EXPR:
traverse_expr(expr->u.while_.cond);
traverse_expr(expr->u.while_.body);
break;
case AST_FOR_EXPR:
traverse_expr(expr->u.for_.lo);
traverse_expr(expr->u.for_.hi);
sym_begin_scope(_env);
sym_enter(_env,
expr->u.for_.var,
escape_entry(_depth, &expr->u.for_.escape));
traverse_expr(expr->u.for_.body);
sym_end_scope(_env);
break;
case AST_BREAK_EXPR:
break;
case AST_LET_EXPR:
sym_begin_scope(_env);
for (p = expr->u.let.decls; p; p = p->next)
traverse_decl(p->data);
traverse_expr(expr->u.let.body);
sym_end_scope(_env);
break;
case AST_ASSIGN_EXPR:
traverse_var(expr->u.assign.var);
traverse_expr(expr->u.assign.expr);
break;
}
}
void esc_find_escape(ast_expr_t expr)
{
_depth = 0;
_env = sym_empty();
traverse_expr(expr);
}
