bool
generic_lambda_fn_p (tree callop)
{
return (LAMBDA_FUNCTION_P (callop)
&& DECL_TEMPLATE_INFO (callop)
&& PRIMARY_TEMPLATE_P (DECL_TI_TEMPLATE (callop)));
}
tree
current_nonlambda_function (void)
{
tree fn = current_function_decl;
while (fn && LAMBDA_FUNCTION_P (fn))
fn = decl_function_context (fn);
return fn;
}
bool
is_capture_proxy (tree decl)
{
return (VAR_P (decl)
&& DECL_HAS_VALUE_EXPR_P (decl)
&& !DECL_ANON_UNION_VAR_P (decl)
&& LAMBDA_FUNCTION_P (DECL_CONTEXT (decl)));
}
bool
is_lambda_ignored_entity (tree val)
{
/* In unevaluated context, look past normal capture proxies. */
if (cp_unevaluated_operand && is_normal_capture_proxy (val))
return true;
/* Always ignore lambda fields, their names are only for debugging. */
if (TREE_CODE (val) == FIELD_DECL
&& CLASSTYPE_LAMBDA_EXPR (DECL_CONTEXT (val)))
return true;
/* None of the lookups that use qualify_lookup want the op() from the
lambda; they want the one from the enclosing class. */
if (TREE_CODE (val) == FUNCTION_DECL && LAMBDA_FUNCTION_P (val))
return true;
return false;
}
void
insert_pending_capture_proxies (void)
{
tree lam;
vec<tree, va_gc> *proxies;
unsigned i;
if (!current_function_decl || !LAMBDA_FUNCTION_P (current_function_decl))
return;
lam = CLASSTYPE_LAMBDA_EXPR (DECL_CONTEXT (current_function_decl));
proxies = LAMBDA_EXPR_PENDING_PROXIES (lam);
for (i = 0; i < vec_safe_length (proxies); ++i)
{
tree var = (*proxies)[i];
insert_capture_proxy (var);
}
release_tree_vector (LAMBDA_EXPR_PENDING_PROXIES (lam));
LAMBDA_EXPR_PENDING_PROXIES (lam) = NULL;
}
tree
current_nonlambda_scope (void)
{
tree scope = current_scope ();
for (;;)
{
if (TREE_CODE (scope) == FUNCTION_DECL
&& LAMBDA_FUNCTION_P (scope))
{
scope = CP_TYPE_CONTEXT (DECL_CONTEXT (scope));
continue;
}
else if (LAMBDA_TYPE_P (scope))
{
scope = CP_TYPE_CONTEXT (scope);
continue;
}
break;
}
return scope;
}
tree
nonlambda_method_basetype (void)
{
tree fn, type;
if (!current_class_ref)
return NULL_TREE;
type = current_class_type;
if (!LAMBDA_TYPE_P (type))
return type;
/* Find the nearest enclosing non-lambda function. */
fn = TYPE_NAME (type);
do
fn = decl_function_context (fn);
while (fn && LAMBDA_FUNCTION_P (fn));
if (!fn || !DECL_NONSTATIC_MEMBER_FUNCTION_P (fn))
return NULL_TREE;
return TYPE_METHOD_BASETYPE (TREE_TYPE (fn));
}
tree
lambda_expr_this_capture (tree lambda, bool add_capture_p)
{
tree result;
tree this_capture = LAMBDA_EXPR_THIS_CAPTURE (lambda);
/* In unevaluated context this isn't an odr-use, so don't capture. */
if (cp_unevaluated_operand)
add_capture_p = false;
/* Try to default capture 'this' if we can. */
if (!this_capture
&& (!add_capture_p
|| LAMBDA_EXPR_DEFAULT_CAPTURE_MODE (lambda) != CPLD_NONE))
{
tree lambda_stack = NULL_TREE;
tree init = NULL_TREE;
/* If we are in a lambda function, we can move out until we hit:
1. a non-lambda function or NSDMI,
2. a lambda function capturing 'this', or
3. a non-default capturing lambda function. */
for (tree tlambda = lambda; ;)
{
lambda_stack = tree_cons (NULL_TREE,
tlambda,
lambda_stack);
if (LAMBDA_EXPR_EXTRA_SCOPE (tlambda)
&& TREE_CODE (LAMBDA_EXPR_EXTRA_SCOPE (tlambda)) == FIELD_DECL)
{
/* In an NSDMI, we don't have a function to look up the decl in,
but the fake 'this' pointer that we're using for parsing is
in scope_chain. */
init = scope_chain->x_current_class_ptr;
gcc_checking_assert
(init && (TREE_TYPE (TREE_TYPE (init))
== current_nonlambda_class_type ()));
break;
}
tree closure_decl = TYPE_NAME (LAMBDA_EXPR_CLOSURE (tlambda));
tree containing_function = decl_function_context (closure_decl);
if (containing_function == NULL_TREE)
/* We ran out of scopes; there's no 'this' to capture. */
break;
if (!LAMBDA_FUNCTION_P (containing_function))
{
/* We found a non-lambda function. */
if (DECL_NONSTATIC_MEMBER_FUNCTION_P (containing_function))
/* First parameter is 'this'. */
init = DECL_ARGUMENTS (containing_function);
break;
}
tlambda
= CLASSTYPE_LAMBDA_EXPR (DECL_CONTEXT (containing_function));
if (LAMBDA_EXPR_THIS_CAPTURE (tlambda))
{
/* An outer lambda has already captured 'this'. */
init = LAMBDA_EXPR_THIS_CAPTURE (tlambda);
break;
}
if (LAMBDA_EXPR_DEFAULT_CAPTURE_MODE (tlambda) == CPLD_NONE)
/* An outer lambda won't let us capture 'this'. */
break;
}
if (init)
{
if (add_capture_p)
this_capture = add_default_capture (lambda_stack,
/*id=*/this_identifier,
init);
else
this_capture = init;
}
}
if (cp_unevaluated_operand)
result = this_capture;
else if (!this_capture)
{
if (add_capture_p)
{
error ("%<this%> was not captured for this lambda function");
result = error_mark_node;
}
else
result = NULL_TREE;
}
else
{
/* To make sure that current_class_ref is for the lambda. */
gcc_assert (TYPE_MAIN_VARIANT (TREE_TYPE (current_class_ref))
== LAMBDA_EXPR_CLOSURE (lambda));
result = this_capture;
/* If 'this' is captured, each use of 'this' is transformed into an
access to the corresponding unnamed data member of the closure
type cast (_expr.cast_ 5.4) to the type of 'this'. [ The cast
ensures that the transformed expression is an rvalue. ] */
result = rvalue (result);
}
return result;
}
