static bool
suitable_for_tail_opt_p (void)
{
- referenced_var_iterator rvi;
- tree var;
-
if (cfun->stdarg)
return false;
- /* No local variable nor structure field should escape to callees. */
- FOR_EACH_REFERENCED_VAR (var, rvi)
- {
- if (!is_global_var (var)
- /* ??? We do not have a suitable predicate for escaping to
- callees. With IPA-PTA the following might be incorrect.
- We want to catch
- foo {
- int i;
- bar (&i);
- foo ();
- }
- where bar might store &i somewhere and in the next
- recursion should not be able to tell if it got the
- same (with tail-recursion applied) or a different
- address. */
- && is_call_clobbered (var))
- return false;
- }
-
return true;
}
/* Returns false when the function is not suitable for tail call optimization
tree m, a;
basic_block abb;
size_t idx;
+ tree var;
+ referenced_var_iterator rvi;
if (!single_succ_p (bb))
return;
func = gimple_call_fndecl (call);
if (func == current_function_decl)
{
- tree arg, var;
- referenced_var_iterator rvi;
+ tree arg;
for (param = DECL_ARGUMENTS (func), idx = 0;
param && idx < gimple_call_num_args (call);
}
if (idx == gimple_call_num_args (call) && !param)
tail_recursion = true;
+ }
- /* Make sure the tail invocation of this function does not refer
- to local variables. */
- FOR_EACH_REFERENCED_VAR (var, rvi)
- {
- if (!is_global_var (var)
- && ref_maybe_used_by_stmt_p (call, var))
- return;
- }
+ /* Make sure the tail invocation of this function does not refer
+ to local variables. */
+ FOR_EACH_REFERENCED_VAR (var, rvi)
+ {
+ if (!is_global_var (var)
+ && ref_maybe_used_by_stmt_p (call, var))
+ return;
}
/* Now check the statements after the call. None of them has virtual