diff options
Diffstat (limited to 'gcc-4.9/gcc/cp/lambda.c')
| -rw-r--r-- | gcc-4.9/gcc/cp/lambda.c | 1095 |
1 files changed, 1095 insertions, 0 deletions
diff --git a/gcc-4.9/gcc/cp/lambda.c b/gcc-4.9/gcc/cp/lambda.c new file mode 100644 index 000000000..0b8b46a81 --- /dev/null +++ b/gcc-4.9/gcc/cp/lambda.c @@ -0,0 +1,1095 @@ +/* Perform the semantic phase of lambda parsing, i.e., the process of + building tree structure, checking semantic consistency, and + building RTL. These routines are used both during actual parsing + and during the instantiation of template functions. + + Copyright (C) 1998-2014 Free Software Foundation, Inc. + + This file is part of GCC. + + GCC is free software; you can redistribute it and/or modify it + under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 3, or (at your option) + any later version. + + GCC is distributed in the hope that it will be useful, but + WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + General Public License for more details. + +You should have received a copy of the GNU General Public License +along with GCC; see the file COPYING3. If not see +<http://www.gnu.org/licenses/>. */ + +#include "config.h" +#include "system.h" +#include "coretypes.h" +#include "tree.h" +#include "stringpool.h" +#include "cgraph.h" +#include "tree-iterator.h" +#include "cp-tree.h" +#include "toplev.h" +#include "vec.h" + +/* Constructor for a lambda expression. */ + +tree +build_lambda_expr (void) +{ + tree lambda = make_node (LAMBDA_EXPR); + LAMBDA_EXPR_DEFAULT_CAPTURE_MODE (lambda) = CPLD_NONE; + LAMBDA_EXPR_CAPTURE_LIST (lambda) = NULL_TREE; + LAMBDA_EXPR_THIS_CAPTURE (lambda) = NULL_TREE; + LAMBDA_EXPR_PENDING_PROXIES (lambda) = NULL; + LAMBDA_EXPR_RETURN_TYPE (lambda) = NULL_TREE; + LAMBDA_EXPR_MUTABLE_P (lambda) = false; + return lambda; +} + +/* Create the closure object for a LAMBDA_EXPR. */ + +tree +build_lambda_object (tree lambda_expr) +{ + /* Build aggregate constructor call. + - cp_parser_braced_list + - cp_parser_functional_cast */ + vec<constructor_elt, va_gc> *elts = NULL; + tree node, expr, type; + location_t saved_loc; + + if (processing_template_decl) + return lambda_expr; + + /* Make sure any error messages refer to the lambda-introducer. */ + saved_loc = input_location; + input_location = LAMBDA_EXPR_LOCATION (lambda_expr); + + for (node = LAMBDA_EXPR_CAPTURE_LIST (lambda_expr); + node; + node = TREE_CHAIN (node)) + { + tree field = TREE_PURPOSE (node); + tree val = TREE_VALUE (node); + + if (field == error_mark_node) + { + expr = error_mark_node; + goto out; + } + + if (DECL_P (val)) + mark_used (val); + + /* Mere mortals can't copy arrays with aggregate initialization, so + do some magic to make it work here. */ + if (TREE_CODE (TREE_TYPE (field)) == ARRAY_TYPE) + val = build_array_copy (val); + else if (DECL_NORMAL_CAPTURE_P (field) + && !DECL_VLA_CAPTURE_P (field) + && TREE_CODE (TREE_TYPE (field)) != REFERENCE_TYPE) + { + /* "the entities that are captured by copy are used to + direct-initialize each corresponding non-static data + member of the resulting closure object." + + There's normally no way to express direct-initialization + from an element of a CONSTRUCTOR, so we build up a special + TARGET_EXPR to bypass the usual copy-initialization. */ + val = force_rvalue (val, tf_warning_or_error); + if (TREE_CODE (val) == TARGET_EXPR) + TARGET_EXPR_DIRECT_INIT_P (val) = true; + } + + CONSTRUCTOR_APPEND_ELT (elts, DECL_NAME (field), val); + } + + expr = build_constructor (init_list_type_node, elts); + CONSTRUCTOR_IS_DIRECT_INIT (expr) = 1; + + /* N2927: "[The closure] class type is not an aggregate." + But we briefly treat it as an aggregate to make this simpler. */ + type = LAMBDA_EXPR_CLOSURE (lambda_expr); + CLASSTYPE_NON_AGGREGATE (type) = 0; + expr = finish_compound_literal (type, expr, tf_warning_or_error); + CLASSTYPE_NON_AGGREGATE (type) = 1; + + out: + input_location = saved_loc; + return expr; +} + +/* Return an initialized RECORD_TYPE for LAMBDA. + LAMBDA must have its explicit captures already. */ + +tree +begin_lambda_type (tree lambda) +{ + tree type; + + { + /* Unique name. This is just like an unnamed class, but we cannot use + make_anon_name because of certain checks against TYPE_ANONYMOUS_P. */ + tree name; + name = make_lambda_name (); + + /* Create the new RECORD_TYPE for this lambda. */ + type = xref_tag (/*tag_code=*/record_type, + name, + /*scope=*/ts_lambda, + /*template_header_p=*/false); + if (type == error_mark_node) + return error_mark_node; + } + + /* Designate it as a struct so that we can use aggregate initialization. */ + CLASSTYPE_DECLARED_CLASS (type) = false; + + /* Cross-reference the expression and the type. */ + LAMBDA_EXPR_CLOSURE (lambda) = type; + CLASSTYPE_LAMBDA_EXPR (type) = lambda; + + /* Clear base types. */ + xref_basetypes (type, /*bases=*/NULL_TREE); + + /* Start the class. */ + type = begin_class_definition (type); + + return type; +} + +/* Returns the type to use for the return type of the operator() of a + closure class. */ + +tree +lambda_return_type (tree expr) +{ + if (expr == NULL_TREE) + return void_type_node; + if (type_unknown_p (expr) + || BRACE_ENCLOSED_INITIALIZER_P (expr)) + { + cxx_incomplete_type_error (expr, TREE_TYPE (expr)); + return void_type_node; + } + gcc_checking_assert (!type_dependent_expression_p (expr)); + return cv_unqualified (type_decays_to (unlowered_expr_type (expr))); +} + +/* Given a LAMBDA_EXPR or closure type LAMBDA, return the op() of the + closure type. */ + +tree +lambda_function (tree lambda) +{ + tree type; + if (TREE_CODE (lambda) == LAMBDA_EXPR) + type = LAMBDA_EXPR_CLOSURE (lambda); + else + type = lambda; + gcc_assert (LAMBDA_TYPE_P (type)); + /* Don't let debug_tree cause instantiation. */ + if (CLASSTYPE_TEMPLATE_INSTANTIATION (type) + && !COMPLETE_OR_OPEN_TYPE_P (type)) + return NULL_TREE; + lambda = lookup_member (type, ansi_opname (CALL_EXPR), + /*protect=*/0, /*want_type=*/false, + tf_warning_or_error); + if (lambda) + lambda = STRIP_TEMPLATE (get_first_fn (lambda)); + return lambda; +} + +/* Returns the type to use for the FIELD_DECL corresponding to the + capture of EXPR. + The caller should add REFERENCE_TYPE for capture by reference. */ + +tree +lambda_capture_field_type (tree expr, bool explicit_init_p) +{ + tree type; + if (explicit_init_p) + { + type = make_auto (); + type = do_auto_deduction (type, expr, type); + } + else + type = non_reference (unlowered_expr_type (expr)); + if (!type || WILDCARD_TYPE_P (type) || type_uses_auto (type) + || DECL_PACK_P (expr)) + { + type = cxx_make_type (DECLTYPE_TYPE); + DECLTYPE_TYPE_EXPR (type) = expr; + DECLTYPE_FOR_LAMBDA_CAPTURE (type) = true; + DECLTYPE_FOR_INIT_CAPTURE (type) = explicit_init_p; + SET_TYPE_STRUCTURAL_EQUALITY (type); + } + return type; +} + +/* Returns true iff DECL is a lambda capture proxy variable created by + build_capture_proxy. */ + +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))); +} + +/* Returns true iff DECL is a capture proxy for a normal capture + (i.e. without explicit initializer). */ + +bool +is_normal_capture_proxy (tree decl) +{ + if (!is_capture_proxy (decl)) + /* It's not a capture proxy. */ + return false; + + if (variably_modified_type_p (TREE_TYPE (decl), NULL_TREE)) + /* VLA capture. */ + return true; + + /* It is a capture proxy, is it a normal capture? */ + tree val = DECL_VALUE_EXPR (decl); + if (val == error_mark_node) + return true; + + gcc_assert (TREE_CODE (val) == COMPONENT_REF); + val = TREE_OPERAND (val, 1); + return DECL_NORMAL_CAPTURE_P (val); +} + +/* VAR is a capture proxy created by build_capture_proxy; add it to the + current function, which is the operator() for the appropriate lambda. */ + +void +insert_capture_proxy (tree var) +{ + cp_binding_level *b; + tree stmt_list; + + /* Put the capture proxy in the extra body block so that it won't clash + with a later local variable. */ + b = current_binding_level; + for (;;) + { + cp_binding_level *n = b->level_chain; + if (n->kind == sk_function_parms) + break; + b = n; + } + pushdecl_with_scope (var, b, false); + + /* And put a DECL_EXPR in the STATEMENT_LIST for the same block. */ + var = build_stmt (DECL_SOURCE_LOCATION (var), DECL_EXPR, var); + stmt_list = (*stmt_list_stack)[1]; + gcc_assert (stmt_list); + append_to_statement_list_force (var, &stmt_list); +} + +/* We've just finished processing a lambda; if the containing scope is also + a lambda, insert any capture proxies that were created while processing + the nested lambda. */ + +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; +} + +/* Given REF, a COMPONENT_REF designating a field in the lambda closure, + return the type we want the proxy to have: the type of the field itself, + with added const-qualification if the lambda isn't mutable and the + capture is by value. */ + +tree +lambda_proxy_type (tree ref) +{ + tree type; + if (ref == error_mark_node) + return error_mark_node; + if (REFERENCE_REF_P (ref)) + ref = TREE_OPERAND (ref, 0); + gcc_assert (TREE_CODE (ref) == COMPONENT_REF); + type = TREE_TYPE (ref); + if (!type || WILDCARD_TYPE_P (non_reference (type))) + { + type = cxx_make_type (DECLTYPE_TYPE); + DECLTYPE_TYPE_EXPR (type) = ref; + DECLTYPE_FOR_LAMBDA_PROXY (type) = true; + SET_TYPE_STRUCTURAL_EQUALITY (type); + } + if (DECL_PACK_P (TREE_OPERAND (ref, 1))) + type = make_pack_expansion (type); + return type; +} + +/* MEMBER is a capture field in a lambda closure class. Now that we're + inside the operator(), build a placeholder var for future lookups and + debugging. */ + +tree +build_capture_proxy (tree member) +{ + tree var, object, fn, closure, name, lam, type; + + if (PACK_EXPANSION_P (member)) + member = PACK_EXPANSION_PATTERN (member); + + closure = DECL_CONTEXT (member); + fn = lambda_function (closure); + lam = CLASSTYPE_LAMBDA_EXPR (closure); + + /* The proxy variable forwards to the capture field. */ + object = build_fold_indirect_ref (DECL_ARGUMENTS (fn)); + object = finish_non_static_data_member (member, object, NULL_TREE); + if (REFERENCE_REF_P (object)) + object = TREE_OPERAND (object, 0); + + /* Remove the __ inserted by add_capture. */ + if (DECL_NORMAL_CAPTURE_P (member)) + name = get_identifier (IDENTIFIER_POINTER (DECL_NAME (member)) + 2); + else + name = DECL_NAME (member); + + type = lambda_proxy_type (object); + + if (DECL_VLA_CAPTURE_P (member)) + { + /* Rebuild the VLA type from the pointer and maxindex. */ + tree field = next_initializable_field (TYPE_FIELDS (type)); + tree ptr = build_simple_component_ref (object, field); + field = next_initializable_field (DECL_CHAIN (field)); + tree max = build_simple_component_ref (object, field); + type = build_cplus_array_type (TREE_TYPE (TREE_TYPE (ptr)), + build_index_type (max)); + type = build_reference_type (type); + REFERENCE_VLA_OK (type) = true; + object = convert (type, ptr); + } + + var = build_decl (input_location, VAR_DECL, name, type); + SET_DECL_VALUE_EXPR (var, object); + DECL_HAS_VALUE_EXPR_P (var) = 1; + DECL_ARTIFICIAL (var) = 1; + TREE_USED (var) = 1; + DECL_CONTEXT (var) = fn; + + if (name == this_identifier) + { + gcc_assert (LAMBDA_EXPR_THIS_CAPTURE (lam) == member); + LAMBDA_EXPR_THIS_CAPTURE (lam) = var; + } + + if (fn == current_function_decl) + insert_capture_proxy (var); + else + vec_safe_push (LAMBDA_EXPR_PENDING_PROXIES (lam), var); + + return var; +} + +/* Return a struct containing a pointer and a length for lambda capture of + an array of runtime length. */ + +static tree +vla_capture_type (tree array_type) +{ + static tree ptr_id, max_id; + tree type = xref_tag (record_type, make_anon_name (), ts_current, false); + xref_basetypes (type, NULL_TREE); + type = begin_class_definition (type); + if (!ptr_id) + { + ptr_id = get_identifier ("ptr"); + max_id = get_identifier ("max"); + } + tree ptrtype = build_pointer_type (TREE_TYPE (array_type)); + tree field = build_decl (input_location, FIELD_DECL, ptr_id, ptrtype); + finish_member_declaration (field); + field = build_decl (input_location, FIELD_DECL, max_id, sizetype); + finish_member_declaration (field); + return finish_struct (type, NULL_TREE); +} + +/* From an ID and INITIALIZER, create a capture (by reference if + BY_REFERENCE_P is true), add it to the capture-list for LAMBDA, + and return it. */ + +tree +add_capture (tree lambda, tree id, tree orig_init, bool by_reference_p, + bool explicit_init_p) +{ + char *buf; + tree type, member, name; + bool vla = false; + bool variadic = false; + tree initializer = orig_init; + + if (PACK_EXPANSION_P (initializer)) + { + initializer = PACK_EXPANSION_PATTERN (initializer); + variadic = true; + } + + if (TREE_CODE (initializer) == TREE_LIST) + initializer = build_x_compound_expr_from_list (initializer, ELK_INIT, + tf_warning_or_error); + type = lambda_capture_field_type (initializer, explicit_init_p); + if (array_of_runtime_bound_p (type)) + { + vla = true; + if (!by_reference_p) + error ("array of runtime bound cannot be captured by copy, " + "only by reference"); + + /* For a VLA, we capture the address of the first element and the + maximum index, and then reconstruct the VLA for the proxy. */ + tree elt = cp_build_array_ref (input_location, initializer, + integer_zero_node, tf_warning_or_error); + initializer = build_constructor_va (init_list_type_node, 2, + NULL_TREE, build_address (elt), + NULL_TREE, array_type_nelts (type)); + type = vla_capture_type (type); + } + else if (variably_modified_type_p (type, NULL_TREE)) + { + error ("capture of variable-size type %qT that is not a C++1y array " + "of runtime bound", type); + if (TREE_CODE (type) == ARRAY_TYPE + && variably_modified_type_p (TREE_TYPE (type), NULL_TREE)) + inform (input_location, "because the array element type %qT has " + "variable size", TREE_TYPE (type)); + type = error_mark_node; + } + else if (by_reference_p) + { + type = build_reference_type (type); + if (!real_lvalue_p (initializer)) + error ("cannot capture %qE by reference", initializer); + } + else + /* Capture by copy requires a complete type. */ + type = complete_type (type); + + /* Add __ to the beginning of the field name so that user code + won't find the field with name lookup. We can't just leave the name + unset because template instantiation uses the name to find + instantiated fields. */ + if (!explicit_init_p) + { + buf = (char *) alloca (IDENTIFIER_LENGTH (id) + 3); + buf[1] = buf[0] = '_'; + memcpy (buf + 2, IDENTIFIER_POINTER (id), + IDENTIFIER_LENGTH (id) + 1); + name = get_identifier (buf); + } + else + /* But captures with explicit initializers are named. */ + name = id; + + /* If TREE_TYPE isn't set, we're still in the introducer, so check + for duplicates. */ + if (!LAMBDA_EXPR_CLOSURE (lambda)) + { + if (IDENTIFIER_MARKED (name)) + { + pedwarn (input_location, 0, + "already captured %qD in lambda expression", id); + return NULL_TREE; + } + IDENTIFIER_MARKED (name) = true; + } + + if (variadic) + type = make_pack_expansion (type); + + /* Make member variable. */ + member = build_decl (input_location, FIELD_DECL, name, type); + DECL_VLA_CAPTURE_P (member) = vla; + + if (!explicit_init_p) + /* Normal captures are invisible to name lookup but uses are replaced + with references to the capture field; we implement this by only + really making them invisible in unevaluated context; see + qualify_lookup. For now, let's make explicitly initialized captures + always visible. */ + DECL_NORMAL_CAPTURE_P (member) = true; + + if (id == this_identifier) + LAMBDA_EXPR_THIS_CAPTURE (lambda) = member; + + /* Add it to the appropriate closure class if we've started it. */ + if (current_class_type + && current_class_type == LAMBDA_EXPR_CLOSURE (lambda)) + finish_member_declaration (member); + + tree listmem = member; + if (variadic) + { + listmem = make_pack_expansion (member); + initializer = orig_init; + } + LAMBDA_EXPR_CAPTURE_LIST (lambda) + = tree_cons (listmem, initializer, LAMBDA_EXPR_CAPTURE_LIST (lambda)); + + if (LAMBDA_EXPR_CLOSURE (lambda)) + return build_capture_proxy (member); + /* For explicit captures we haven't started the function yet, so we wait + and build the proxy from cp_parser_lambda_body. */ + return NULL_TREE; +} + +/* Register all the capture members on the list CAPTURES, which is the + LAMBDA_EXPR_CAPTURE_LIST for the lambda after the introducer. */ + +void +register_capture_members (tree captures) +{ + if (captures == NULL_TREE) + return; + + register_capture_members (TREE_CHAIN (captures)); + + tree field = TREE_PURPOSE (captures); + if (PACK_EXPANSION_P (field)) + field = PACK_EXPANSION_PATTERN (field); + + /* We set this in add_capture to avoid duplicates. */ + IDENTIFIER_MARKED (DECL_NAME (field)) = false; + finish_member_declaration (field); +} + +/* Similar to add_capture, except this works on a stack of nested lambdas. + BY_REFERENCE_P in this case is derived from the default capture mode. + Returns the capture for the lambda at the bottom of the stack. */ + +tree +add_default_capture (tree lambda_stack, tree id, tree initializer) +{ + bool this_capture_p = (id == this_identifier); + + tree var = NULL_TREE; + + tree saved_class_type = current_class_type; + + tree node; + + for (node = lambda_stack; + node; + node = TREE_CHAIN (node)) + { + tree lambda = TREE_VALUE (node); + + current_class_type = LAMBDA_EXPR_CLOSURE (lambda); + if (DECL_PACK_P (initializer)) + initializer = make_pack_expansion (initializer); + var = add_capture (lambda, + id, + initializer, + /*by_reference_p=*/ + (!this_capture_p + && (LAMBDA_EXPR_DEFAULT_CAPTURE_MODE (lambda) + == CPLD_REFERENCE)), + /*explicit_init_p=*/false); + initializer = convert_from_reference (var); + } + + current_class_type = saved_class_type; + + return var; +} + +/* Return the capture pertaining to a use of 'this' in LAMBDA, in the form of an + INDIRECT_REF, possibly adding it through default capturing. */ + +tree +lambda_expr_this_capture (tree lambda) +{ + tree result; + + tree this_capture = LAMBDA_EXPR_THIS_CAPTURE (lambda); + + /* In unevaluated context this isn't an odr-use, so just return the + nearest 'this'. */ + if (cp_unevaluated_operand) + { + /* In an NSDMI the fake 'this' pointer that we're using for + parsing is in scope_chain. */ + if (LAMBDA_EXPR_EXTRA_SCOPE (lambda) + && TREE_CODE (LAMBDA_EXPR_EXTRA_SCOPE (lambda)) == FIELD_DECL) + return scope_chain->x_current_class_ptr; + return lookup_name (this_identifier); + } + + /* Try to default capture 'this' if we can. */ + if (!this_capture + && 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) + this_capture = add_default_capture (lambda_stack, + /*id=*/this_identifier, + init); + } + + if (!this_capture) + { + error ("%<this%> was not captured for this lambda function"); + result = error_mark_node; + } + 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; +} + +/* We don't want to capture 'this' until we know we need it, i.e. after + overload resolution has chosen a non-static member function. At that + point we call this function to turn a dummy object into a use of the + 'this' capture. */ + +tree +maybe_resolve_dummy (tree object) +{ + if (!is_dummy_object (object)) + return object; + + tree type = TYPE_MAIN_VARIANT (TREE_TYPE (object)); + gcc_assert (!TYPE_PTR_P (type)); + + if (type != current_class_type + && current_class_type + && LAMBDA_TYPE_P (current_class_type) + && lambda_function (current_class_type) + && DERIVED_FROM_P (type, current_nonlambda_class_type ())) + { + /* In a lambda, need to go through 'this' capture. */ + tree lam = CLASSTYPE_LAMBDA_EXPR (current_class_type); + tree cap = lambda_expr_this_capture (lam); + object = build_x_indirect_ref (EXPR_LOCATION (object), cap, + RO_NULL, tf_warning_or_error); + } + + return object; +} + +/* Returns the method basetype of the innermost non-lambda function, or + NULL_TREE if none. */ + +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)); +} + +/* Helper function for maybe_add_lambda_conv_op; build a CALL_EXPR with + indicated FN and NARGS, but do not initialize the return type or any of the + argument slots. */ + +static tree +prepare_op_call (tree fn, int nargs) +{ + tree t; + + t = build_vl_exp (CALL_EXPR, nargs + 3); + CALL_EXPR_FN (t) = fn; + CALL_EXPR_STATIC_CHAIN (t) = NULL; + + return t; +} + +/* If the closure TYPE has a static op(), also add a conversion to function + pointer. */ + +void +maybe_add_lambda_conv_op (tree type) +{ + bool nested = (current_function_decl != NULL_TREE); + tree callop = lambda_function (type); + + if (LAMBDA_EXPR_CAPTURE_LIST (CLASSTYPE_LAMBDA_EXPR (type)) != NULL_TREE) + return; + + if (processing_template_decl) + return; + + bool const generic_lambda_p + = (DECL_TEMPLATE_INFO (callop) + && DECL_TEMPLATE_RESULT (DECL_TI_TEMPLATE (callop)) == callop); + + if (!generic_lambda_p && DECL_INITIAL (callop) == NULL_TREE) + { + /* If the op() wasn't instantiated due to errors, give up. */ + gcc_assert (errorcount || sorrycount); + return; + } + + /* Non-template conversion operators are defined directly with build_call_a + and using DIRECT_ARGVEC for arguments (including 'this'). Templates are + deferred and the CALL is built in-place. In the case of a deduced return + call op, the decltype expression, DECLTYPE_CALL, used as a substitute for + the return type is also built in-place. The arguments of DECLTYPE_CALL in + the return expression may differ in flags from those in the body CALL. In + particular, parameter pack expansions are marked PACK_EXPANSION_LOCAL_P in + the body CALL, but not in DECLTYPE_CALL. */ + + vec<tree, va_gc> *direct_argvec = 0; + tree decltype_call = 0, call = 0; + tree fn_result = TREE_TYPE (TREE_TYPE (callop)); + + if (generic_lambda_p) + { + /* Prepare the dependent member call for the static member function + '_FUN' and, potentially, prepare another call to be used in a decltype + return expression for a deduced return call op to allow for simple + implementation of the conversion operator. */ + + tree instance = build_nop (type, null_pointer_node); + tree objfn = build_min (COMPONENT_REF, NULL_TREE, + instance, DECL_NAME (callop), NULL_TREE); + int nargs = list_length (DECL_ARGUMENTS (callop)) - 1; + + call = prepare_op_call (objfn, nargs); + if (type_uses_auto (fn_result)) + decltype_call = prepare_op_call (objfn, nargs); + } + else + { + direct_argvec = make_tree_vector (); + direct_argvec->quick_push (build1 (NOP_EXPR, + TREE_TYPE (DECL_ARGUMENTS (callop)), + null_pointer_node)); + } + + /* Copy CALLOP's argument list (as per 'copy_list') as FN_ARGS in order to + declare the static member function "_FUN" below. For each arg append to + DIRECT_ARGVEC (for the non-template case) or populate the pre-allocated + call args (for the template case). If a parameter pack is found, expand + it, flagging it as PACK_EXPANSION_LOCAL_P for the body call. */ + + tree fn_args = NULL_TREE; + { + int ix = 0; + tree src = DECL_CHAIN (DECL_ARGUMENTS (callop)); + tree tgt; + + while (src) + { + tree new_node = copy_node (src); + + if (!fn_args) + fn_args = tgt = new_node; + else + { + TREE_CHAIN (tgt) = new_node; + tgt = new_node; + } + + mark_exp_read (tgt); + + if (generic_lambda_p) + { + if (DECL_PACK_P (tgt)) + { + tree a = make_pack_expansion (tgt); + if (decltype_call) + CALL_EXPR_ARG (decltype_call, ix) = copy_node (a); + PACK_EXPANSION_LOCAL_P (a) = true; + CALL_EXPR_ARG (call, ix) = a; + } + else + { + tree a = convert_from_reference (tgt); + CALL_EXPR_ARG (call, ix) = a; + if (decltype_call) + CALL_EXPR_ARG (decltype_call, ix) = copy_node (a); + } + ++ix; + } + else + vec_safe_push (direct_argvec, tgt); + + src = TREE_CHAIN (src); + } + } + + + if (generic_lambda_p) + { + if (decltype_call) + { + ++processing_template_decl; + fn_result = finish_decltype_type + (decltype_call, /*id_expression_or_member_access_p=*/false, + tf_warning_or_error); + --processing_template_decl; + } + } + else + call = build_call_a (callop, + direct_argvec->length (), + direct_argvec->address ()); + + CALL_FROM_THUNK_P (call) = 1; + + tree stattype = build_function_type (fn_result, FUNCTION_ARG_CHAIN (callop)); + + /* First build up the conversion op. */ + + tree rettype = build_pointer_type (stattype); + tree name = mangle_conv_op_name_for_type (rettype); + tree thistype = cp_build_qualified_type (type, TYPE_QUAL_CONST); + tree fntype = build_method_type_directly (thistype, rettype, void_list_node); + tree convfn = build_lang_decl (FUNCTION_DECL, name, fntype); + tree fn = convfn; + DECL_SOURCE_LOCATION (fn) = DECL_SOURCE_LOCATION (callop); + + if (TARGET_PTRMEMFUNC_VBIT_LOCATION == ptrmemfunc_vbit_in_pfn + && DECL_ALIGN (fn) < 2 * BITS_PER_UNIT) + DECL_ALIGN (fn) = 2 * BITS_PER_UNIT; + + SET_OVERLOADED_OPERATOR_CODE (fn, TYPE_EXPR); + grokclassfn (type, fn, NO_SPECIAL); + set_linkage_according_to_type (type, fn); + rest_of_decl_compilation (fn, toplevel_bindings_p (), at_eof); + DECL_IN_AGGR_P (fn) = 1; + DECL_ARTIFICIAL (fn) = 1; + DECL_NOT_REALLY_EXTERN (fn) = 1; + DECL_DECLARED_INLINE_P (fn) = 1; + DECL_ARGUMENTS (fn) = build_this_parm (fntype, TYPE_QUAL_CONST); + if (nested) + DECL_INTERFACE_KNOWN (fn) = 1; + + if (generic_lambda_p) + fn = add_inherited_template_parms (fn, DECL_TI_TEMPLATE (callop)); + + add_method (type, fn, NULL_TREE); + + /* Generic thunk code fails for varargs; we'll complain in mark_used if + the conversion op is used. */ + if (varargs_function_p (callop)) + { + DECL_DELETED_FN (fn) = 1; + return; + } + + /* Now build up the thunk to be returned. */ + + name = get_identifier ("_FUN"); + tree statfn = build_lang_decl (FUNCTION_DECL, name, stattype); + fn = statfn; + DECL_SOURCE_LOCATION (fn) = DECL_SOURCE_LOCATION (callop); + if (TARGET_PTRMEMFUNC_VBIT_LOCATION == ptrmemfunc_vbit_in_pfn + && DECL_ALIGN (fn) < 2 * BITS_PER_UNIT) + DECL_ALIGN (fn) = 2 * BITS_PER_UNIT; + grokclassfn (type, fn, NO_SPECIAL); + set_linkage_according_to_type (type, fn); + rest_of_decl_compilation (fn, toplevel_bindings_p (), at_eof); + DECL_IN_AGGR_P (fn) = 1; + DECL_ARTIFICIAL (fn) = 1; + DECL_NOT_REALLY_EXTERN (fn) = 1; + DECL_DECLARED_INLINE_P (fn) = 1; + DECL_STATIC_FUNCTION_P (fn) = 1; + DECL_ARGUMENTS (fn) = fn_args; + for (tree arg = fn_args; arg; arg = DECL_CHAIN (arg)) + { + /* Avoid duplicate -Wshadow warnings. */ + DECL_NAME (arg) = NULL_TREE; + DECL_CONTEXT (arg) = fn; + } + if (nested) + DECL_INTERFACE_KNOWN (fn) = 1; + + if (generic_lambda_p) + fn = add_inherited_template_parms (fn, DECL_TI_TEMPLATE (callop)); + + add_method (type, fn, NULL_TREE); + + if (nested) + push_function_context (); + else + /* Still increment function_depth so that we don't GC in the + middle of an expression. */ + ++function_depth; + + /* Generate the body of the thunk. */ + + start_preparsed_function (statfn, NULL_TREE, + SF_PRE_PARSED | SF_INCLASS_INLINE); + if (DECL_ONE_ONLY (statfn)) + { + /* Put the thunk in the same comdat group as the call op. */ + symtab_add_to_same_comdat_group + (cgraph_get_create_node (statfn), + cgraph_get_create_node (callop)); + } + tree body = begin_function_body (); + tree compound_stmt = begin_compound_stmt (0); + if (!generic_lambda_p) + { + set_flags_from_callee (call); + if (MAYBE_CLASS_TYPE_P (TREE_TYPE (call))) + call = build_cplus_new (TREE_TYPE (call), call, tf_warning_or_error); + } + call = convert_from_reference (call); + finish_return_stmt (call); + + finish_compound_stmt (compound_stmt); + finish_function_body (body); + + fn = finish_function (/*inline*/2); + if (!generic_lambda_p) + expand_or_defer_fn (fn); + + /* Generate the body of the conversion op. */ + + start_preparsed_function (convfn, NULL_TREE, + SF_PRE_PARSED | SF_INCLASS_INLINE); + body = begin_function_body (); + compound_stmt = begin_compound_stmt (0); + + /* decl_needed_p needs to see that it's used. */ + TREE_USED (statfn) = 1; + finish_return_stmt (decay_conversion (statfn, tf_warning_or_error)); + + finish_compound_stmt (compound_stmt); + finish_function_body (body); + + fn = finish_function (/*inline*/2); + if (!generic_lambda_p) + expand_or_defer_fn (fn); + + if (nested) + pop_function_context (); + else + --function_depth; +} + +/* Returns true iff VAL is a lambda-related declaration which should + be ignored by unqualified lookup. */ + +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; +} |