blob: 9baa46d2243af6d3c682b94499944893c728041d [file] [log] [blame]
/* Implement classes and message passing for Objective C.
Copyright (C) 1992-2021 Free Software Foundation, Inc.
Contributed by Steve Naroff.
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 "tm.h"
#include "tree.h"
#include "stringpool.h"
#include "stor-layout.h"
#include "attribs.h"
#ifdef OBJCPLUS
#include "cp/cp-tree.h"
#else
#include "c/c-tree.h"
#include "c/c-lang.h"
#endif
#include "c-family/c-objc.h"
#include "langhooks.h"
#include "objc-act.h"
#include "objc-map.h"
#include "function.h"
#include "toplev.h"
#include "debug.h"
#include "c-family/c-target.h"
#include "intl.h"
#include "cgraph.h"
#include "tree-iterator.h"
/* Different initialization, code gen and meta data generation for each
runtime. */
#include "objc-runtime-hooks.h"
/* Routines used mainly by the runtimes. */
#include "objc-runtime-shared-support.h"
/* For default_tree_printer (). */
/* For enum gimplify_status */
#include "gimple-expr.h"
#include "gimplify.h"
/* For encode_method_prototype(). */
#include "objc-encoding.h"
static unsigned int should_call_super_dealloc = 0;
/* When building Objective-C++, we are not linking against the C front-end
and so need to replicate the C tree-construction functions in some way. */
#ifdef OBJCPLUS
#define OBJCP_REMAP_FUNCTIONS
#include "objcp-decl.h"
#endif /* OBJCPLUS */
/* This is the default way of generating a method name. */
/* This has the problem that "test_method:argument:" and
"test:method_argument:" will generate the same name
("_i_Test__test_method_argument_" for an instance method of the
class "Test"), so you can't have them both in the same class!
Moreover, the demangling (going from
"_i_Test__test_method_argument" back to the original name) is
undefined because there are two correct ways of demangling the
name. */
#ifndef OBJC_GEN_METHOD_LABEL
#define OBJC_GEN_METHOD_LABEL(BUF, IS_INST, CLASS_NAME, CAT_NAME, SEL_NAME, NUM) \
do { \
char *temp; \
sprintf ((BUF), "_%s_%s_%s_%s", \
((IS_INST) ? "i" : "c"), \
(CLASS_NAME), \
((CAT_NAME)? (CAT_NAME) : ""), \
(SEL_NAME)); \
for (temp = (BUF); *temp; temp++) \
if (*temp == ':') *temp = '_'; \
} while (0)
#endif
/* These need specifying. */
#ifndef OBJC_FORWARDING_STACK_OFFSET
#define OBJC_FORWARDING_STACK_OFFSET 0
#endif
#ifndef OBJC_FORWARDING_MIN_OFFSET
#define OBJC_FORWARDING_MIN_OFFSET 0
#endif
/*** Private Interface (procedures) ***/
/* Init stuff. */
static void synth_module_prologue (void);
/* Code generation. */
static tree start_class (enum tree_code, tree, tree, tree, tree);
static tree continue_class (tree);
static void finish_class (tree);
static void start_method_def (tree, tree);
static tree start_protocol (enum tree_code, tree, tree, tree);
static tree build_method_decl (enum tree_code, tree, tree, tree, bool);
static tree objc_add_method (tree, tree, int, bool);
static tree add_instance_variable (tree, objc_ivar_visibility_kind, tree);
static tree build_ivar_reference (tree);
static tree is_ivar (tree, tree);
/* We only need the following for ObjC; ObjC++ will use C++'s definition
of DERIVED_FROM_P. */
#ifndef OBJCPLUS
static bool objc_derived_from_p (tree, tree);
#define DERIVED_FROM_P(PARENT, CHILD) objc_derived_from_p (PARENT, CHILD)
#endif
/* Property. */
static void objc_gen_property_data (tree, tree);
static void objc_synthesize_getter (tree, tree, tree);
static void objc_synthesize_setter (tree, tree, tree);
static tree lookup_property (tree, tree);
static tree lookup_property_in_list (tree, tree);
static tree lookup_property_in_protocol_list (tree, tree);
static void build_common_objc_property_accessor_helpers (void);
static void objc_xref_basetypes (tree, tree);
static tree get_class_ivars (tree, bool);
static void build_fast_enumeration_state_template (void);
#ifdef OBJCPLUS
static void objc_generate_cxx_cdtors (void);
#endif
/* objc attribute */
static void objc_decl_method_attributes (tree*, tree, int);
static tree build_keyword_selector (tree);
static void hash_init (void);
/* Hash tables to manage the global pool of method prototypes. Each
of these maps map a method name (selector) identifier to either a
single tree (for methods with a single method prototype) or a
TREE_VEC (for methods with multiple method prototypes). */
static GTY(()) objc_map_t instance_method_map = 0;
static GTY(()) objc_map_t class_method_map = 0;
/* Hash tables to manage the global pool of class names. */
static GTY(()) objc_map_t class_name_map = 0;
static GTY(()) objc_map_t alias_name_map = 0;
static tree lookup_method (tree, tree);
static tree lookup_method_static (tree, tree, int);
static void interface_hash_init (void);
static tree add_interface (tree, tree);
static void add_category (tree, tree);
static inline tree lookup_category (tree, tree);
/* Protocols. */
static tree lookup_protocol (tree, bool, bool);
static tree lookup_and_install_protocols (tree, bool);
#ifdef OBJCPLUS
static void really_start_method (tree, tree);
#else
static void really_start_method (tree, struct c_arg_info *);
#endif
static int comp_proto_with_proto (tree, tree, int);
static tree objc_decay_parm_type (tree);
/* Utilities for debugging and error diagnostics. */
static char *gen_type_name (tree);
static char *gen_type_name_0 (tree);
static char *gen_method_decl (tree);
static char *gen_declaration (tree);
/* Everything else. */
static void generate_struct_by_value_array (void) ATTRIBUTE_NORETURN;
static void mark_referenced_methods (void);
static bool objc_type_valid_for_messaging (tree type, bool allow_classes);
static tree check_duplicates (tree, int, int);
/*** Private Interface (data) ***/
/* Flags for lookup_method_static(). */
/* Look for class methods. */
#define OBJC_LOOKUP_CLASS 1
/* Do not examine superclasses. */
#define OBJC_LOOKUP_NO_SUPER 2
/* Disable returning an instance method of a root class when a class
method can't be found. */
#define OBJC_LOOKUP_NO_INSTANCE_METHODS_OF_ROOT_CLASS 4
/* The OCTI_... enumeration itself is in objc/objc-act.h. */
tree objc_global_trees[OCTI_MAX];
struct imp_entry *imp_list = 0;
int imp_count = 0; /* `@implementation' */
int cat_count = 0; /* `@category' */
objc_ivar_visibility_kind objc_ivar_visibility, objc_default_ivar_visibility;
/* Use to generate method labels. */
static int method_slot = 0;
/* Flag to say whether methods in a protocol are optional or
required. */
static bool objc_method_optional_flag = false;
static int objc_collecting_ivars = 0;
/* Flag that is set to 'true' while we are processing a class
extension. Since a class extension just "reopens" the main
@interface, this can be used to determine if we are in the main
@interface, or in a class extension. */
static bool objc_in_class_extension = false;
static char *errbuf; /* Buffer for error diagnostics */
/* An array of all the local variables in the current function that
need to be marked as volatile. */
vec<tree, va_gc> *local_variables_to_volatilize = NULL;
/* Store all constructed constant strings in a hash table so that
they get uniqued properly. */
struct GTY((for_user)) string_descriptor {
/* The literal argument . */
tree literal;
/* The resulting constant string. */
tree constructor;
};
struct objc_string_hasher : ggc_ptr_hash<string_descriptor>
{
static hashval_t hash (string_descriptor *);
static bool equal (string_descriptor *, string_descriptor *);
};
static GTY(()) hash_table<objc_string_hasher> *string_htab;
FILE *gen_declaration_file;
/* Hooks for stuff that differs between runtimes. */
objc_runtime_hooks runtime;
/* Create a temporary variable of type 'type'. If 'name' is set, uses
the specified name, else use no name. Returns the declaration of
the type. The 'name' is mostly useful for debugging.
*/
tree
objc_create_temporary_var (tree type, const char *name)
{
tree decl;
if (name != NULL)
{
decl = build_decl (input_location,
VAR_DECL, get_identifier (name), type);
}
else
{
decl = build_decl (input_location,
VAR_DECL, NULL_TREE, type);
}
TREE_USED (decl) = 1;
DECL_ARTIFICIAL (decl) = 1;
DECL_IGNORED_P (decl) = 1;
DECL_CONTEXT (decl) = current_function_decl;
return decl;
}
/* Some platforms pass small structures through registers versus
through an invisible pointer. Determine at what size structure is
the transition point between the two possibilities. */
static void
generate_struct_by_value_array (void)
{
tree type;
tree decls;
int i, j;
int aggregate_in_mem[32];
int found = 0;
/* Presumably no platform passes 32 byte structures in a register. */
/* ??? As an example, m64/ppc/Darwin can pass up to 8*long+13*double
in registers. */
for (i = 1; i < 32; i++)
{
char buffer[5];
tree *chain = NULL;
/* Create an unnamed struct that has `i' character components */
type = objc_start_struct (NULL_TREE);
strcpy (buffer, "c1");
decls = add_field_decl (char_type_node, buffer, &chain);
for (j = 1; j < i; j++)
{
sprintf (buffer, "c%d", j + 1);
add_field_decl (char_type_node, buffer, &chain);
}
objc_finish_struct (type, decls);
aggregate_in_mem[i] = aggregate_value_p (type, 0);
if (!aggregate_in_mem[i])
found = 1;
}
/* We found some structures that are returned in registers instead of memory
so output the necessary data. */
if (found)
{
for (i = 31; i >= 0; i--)
if (!aggregate_in_mem[i])
break;
printf ("#define OBJC_MAX_STRUCT_BY_VALUE %d\n", i);
}
exit (0);
}
bool
objc_init (void)
{
bool ok;
#ifdef OBJCPLUS
if (cxx_init () == false)
#else
if (c_objc_common_init () == false)
#endif
return false;
/* print_struct_values is triggered by -print-runtime-info (used
when building libobjc, with an empty file as input). It does not
require any ObjC setup, and it never returns.
-fcompare-debug is used to check the compiler output; we are
executed twice, once with flag_compare_debug set, and once with
it not set. If the flag is used together with
-print-runtime-info, we want to print the runtime info only once,
else it would be output in duplicate. So we check
flag_compare_debug to output it in only one of the invocations.
As a side effect, this also that means -fcompare-debug
-print-runtime-info will run the compiler twice, and compare the
generated assembler file; the first time the compiler exits
immediately (producing no file), and the second time it compiles
an empty file. This checks, as a side effect, that compiling an
empty file produces no assembler output. */
if (print_struct_values && !flag_compare_debug)
generate_struct_by_value_array ();
/* Set up stuff used by FE parser and all runtimes. */
errbuf = XNEWVEC (char, 1024 * 10);
interface_hash_init ();
hash_init ();
objc_encoding_init ();
/* ... and then check flags and set-up for the selected runtime ... */
if (flag_next_runtime && flag_objc_abi >= 2)
ok = objc_next_runtime_abi_02_init (&runtime);
else if (flag_next_runtime)
ok = objc_next_runtime_abi_01_init (&runtime);
else
ok = objc_gnu_runtime_abi_01_init (&runtime);
/* If that part of the setup failed - bail out immediately. */
if (!ok)
return false;
/* Determine the default visibility for instance variables. */
switch (default_ivar_visibility)
{
case IVAR_VISIBILITY_PRIVATE:
objc_default_ivar_visibility = OBJC_IVAR_VIS_PRIVATE;
break;
case IVAR_VISIBILITY_PUBLIC:
objc_default_ivar_visibility = OBJC_IVAR_VIS_PUBLIC;
break;
case IVAR_VISIBILITY_PACKAGE:
objc_default_ivar_visibility = OBJC_IVAR_VIS_PACKAGE;
break;
default:
objc_default_ivar_visibility = OBJC_IVAR_VIS_PROTECTED;
}
/* Generate general types and push runtime-specific decls to file scope. */
synth_module_prologue ();
return true;
}
/* This is called at the end of parsing by the C/C++ parsers. */
void
objc_write_global_declarations (void)
{
mark_referenced_methods ();
/* A missing @end might not be detected by the parser. */
if (objc_implementation_context)
{
warning (0, "%<@end%> missing in implementation context");
finish_class (objc_implementation_context);
objc_ivar_chain = NULL_TREE;
objc_implementation_context = NULL_TREE;
}
if (warn_selector)
{
objc_map_iterator_t i;
objc_map_iterator_initialize (class_method_map, &i);
while (objc_map_iterator_move_to_next (class_method_map, &i))
check_duplicates (objc_map_iterator_current_value (class_method_map, i), 0, 1);
objc_map_iterator_initialize (instance_method_map, &i);
while (objc_map_iterator_move_to_next (instance_method_map, &i))
check_duplicates (objc_map_iterator_current_value (instance_method_map, i), 0, 0);
}
/* TODO: consider an early exit here if either errorcount or sorrycount
is non-zero. Not only is it wasting time to generate the metadata,
it needlessly imposes need to re-check for things that are already
determined to be errors. */
/* Finalize Objective-C runtime data. No need to generate tables
and code if only checking syntax, or if generating a PCH file. */
if (!flag_syntax_only && !pch_file)
{
location_t saved_location;
/* If gen_declaration desired, open the output file. */
if (flag_gen_declaration)
{
char * const dumpname = concat (dump_base_name, ".decl", NULL);
gen_declaration_file = fopen (dumpname, "w");
if (gen_declaration_file == 0)
fatal_error (input_location, "cannot open %s: %m", dumpname);
free (dumpname);
}
/* Set the input location to BUILTINS_LOCATION. This is good
for error messages, in case any is generated while producing
the metadata, but it also silences warnings that would be
produced when compiling with -Wpadded in case when padding is
automatically added to the built-in runtime data structure
declarations. We know about this padding, and it is fine; we
don't want users to see any warnings about it if they use
-Wpadded. */
saved_location = input_location;
input_location = BUILTINS_LOCATION;
/* Compute and emit the meta-data tables for this runtime. */
(*runtime.generate_metadata) ();
/* Restore the original location, just in case it mattered. */
input_location = saved_location;
/* ... and then close any declaration file we opened. */
if (gen_declaration_file)
fclose (gen_declaration_file);
}
}
/* Return the first occurrence of a method declaration corresponding
to sel_name in rproto_list. Search rproto_list recursively.
If is_class is 0, search for instance methods, otherwise for class
methods. */
static tree
lookup_method_in_protocol_list (tree rproto_list, tree sel_name,
int is_class)
{
tree rproto, p, m;
for (rproto = rproto_list; rproto; rproto = TREE_CHAIN (rproto))
{
p = TREE_VALUE (rproto);
m = NULL_TREE;
if (TREE_CODE (p) == PROTOCOL_INTERFACE_TYPE)
{
/* First, search the @required protocol methods. */
if (is_class)
m = lookup_method (PROTOCOL_CLS_METHODS (p), sel_name);
else
m = lookup_method (PROTOCOL_NST_METHODS (p), sel_name);
if (m)
return m;
/* If still not found, search the @optional protocol methods. */
if (is_class)
m = lookup_method (PROTOCOL_OPTIONAL_CLS_METHODS (p), sel_name);
else
m = lookup_method (PROTOCOL_OPTIONAL_NST_METHODS (p), sel_name);
if (m)
return m;
/* If still not found, search the attached protocols. */
if (PROTOCOL_LIST (p))
m = lookup_method_in_protocol_list (PROTOCOL_LIST (p),
sel_name, is_class);
if (m)
return m;
}
else
{
; /* An identifier...if we could not find a protocol. */
}
}
return 0;
}
static tree
lookup_protocol_in_reflist (tree rproto_list, tree lproto)
{
tree rproto, p;
/* Make sure the protocol is supported by the object on the rhs. */
if (TREE_CODE (lproto) == PROTOCOL_INTERFACE_TYPE)
{
tree fnd = 0;
for (rproto = rproto_list; rproto; rproto = TREE_CHAIN (rproto))
{
p = TREE_VALUE (rproto);
if (TREE_CODE (p) == PROTOCOL_INTERFACE_TYPE)
{
if (lproto == p)
fnd = lproto;
else if (PROTOCOL_LIST (p))
fnd = lookup_protocol_in_reflist (PROTOCOL_LIST (p), lproto);
}
if (fnd)
return fnd;
}
}
else
{
; /* An identifier...if we could not find a protocol. */
}
return 0;
}
void
objc_start_class_interface (tree klass, location_t name_loc, tree super_class,
tree protos, tree attributes)
{
if (flag_objc1_only && attributes)
error_at (name_loc, "class attributes are not available in Objective-C 1.0");
objc_interface_context
= objc_ivar_context
= start_class (CLASS_INTERFACE_TYPE, klass, super_class, protos, attributes);
objc_ivar_visibility = objc_default_ivar_visibility;
}
void
objc_start_category_interface (tree klass, tree categ,
tree protos, tree attributes)
{
if (attributes)
{
if (flag_objc1_only)
error_at (input_location, "category attributes are not available in Objective-C 1.0");
else
warning_at (input_location, OPT_Wattributes,
"category attributes are not available in this version"
" of the compiler, (ignored)");
}
if (categ == NULL_TREE)
{
if (flag_objc1_only)
error_at (input_location, "class extensions are not available in Objective-C 1.0");
else
{
/* Iterate over all the classes and categories implemented
up to now in this compilation unit. */
struct imp_entry *t;
for (t = imp_list; t; t = t->next)
{
/* If we find a class @implementation with the same name
as the one we are extending, produce an error. */
if (TREE_CODE (t->imp_context) == CLASS_IMPLEMENTATION_TYPE
&& IDENTIFIER_POINTER (CLASS_NAME (t->imp_context)) == IDENTIFIER_POINTER (klass))
error_at (input_location,
"class extension for class %qE declared after its %<@implementation%>",
klass);
}
}
}
objc_interface_context
= start_class (CATEGORY_INTERFACE_TYPE, klass, categ, protos, NULL_TREE);
objc_ivar_chain
= continue_class (objc_interface_context);
}
void
objc_start_protocol (tree name, tree protos, tree attributes)
{
if (flag_objc1_only && attributes)
error_at (input_location, "protocol attributes are not available in Objective-C 1.0");
objc_interface_context
= start_protocol (PROTOCOL_INTERFACE_TYPE, name, protos, attributes);
objc_method_optional_flag = false;
}
void
objc_continue_interface (void)
{
objc_ivar_chain
= continue_class (objc_interface_context);
}
void
objc_finish_interface (void)
{
finish_class (objc_interface_context);
objc_interface_context = NULL_TREE;
objc_method_optional_flag = false;
objc_in_class_extension = false;
}
void
objc_start_class_implementation (tree klass, tree super_class)
{
objc_implementation_context
= objc_ivar_context
= start_class (CLASS_IMPLEMENTATION_TYPE, klass, super_class, NULL_TREE,
NULL_TREE);
objc_ivar_visibility = objc_default_ivar_visibility;
}
void
objc_start_category_implementation (tree klass, tree categ)
{
objc_implementation_context
= start_class (CATEGORY_IMPLEMENTATION_TYPE, klass, categ, NULL_TREE,
NULL_TREE);
objc_ivar_chain
= continue_class (objc_implementation_context);
}
void
objc_continue_implementation (void)
{
objc_ivar_chain
= continue_class (objc_implementation_context);
}
void
objc_finish_implementation (void)
{
#ifdef OBJCPLUS
if (flag_objc_call_cxx_cdtors)
objc_generate_cxx_cdtors ();
#endif
if (objc_implementation_context)
{
finish_class (objc_implementation_context);
objc_ivar_chain = NULL_TREE;
objc_implementation_context = NULL_TREE;
}
else
warning (0, "%<@end%> must appear in an @implementation context");
}
void
objc_set_visibility (objc_ivar_visibility_kind visibility)
{
if (visibility == OBJC_IVAR_VIS_PACKAGE)
{
if (flag_objc1_only)
error ("%<@package%> is not available in Objective-C 1.0");
else
warning (0, "%<@package%> presently has the same effect as %<@public%>");
}
objc_ivar_visibility = visibility;
}
void
objc_set_method_opt (bool optional)
{
if (flag_objc1_only)
{
if (optional)
error_at (input_location, "%<@optional%> is not available in Objective-C 1.0");
else
error_at (input_location, "%<@required%> is not available in Objective-C 1.0");
}
objc_method_optional_flag = optional;
if (!objc_interface_context
|| TREE_CODE (objc_interface_context) != PROTOCOL_INTERFACE_TYPE)
{
if (optional)
error ("%<@optional%> is allowed in @protocol context only");
else
error ("%<@required%> is allowed in @protocol context only");
objc_method_optional_flag = false;
}
}
/* This routine looks for a given PROPERTY in a list of CLASS, CATEGORY, or
PROTOCOL. */
static tree
lookup_property_in_list (tree chain, tree property)
{
tree x;
for (x = CLASS_PROPERTY_DECL (chain); x; x = TREE_CHAIN (x))
if (PROPERTY_NAME (x) == property)
return x;
return NULL_TREE;
}
/* This routine looks for a given PROPERTY in the tree chain of RPROTO_LIST. */
static tree lookup_property_in_protocol_list (tree rproto_list, tree property)
{
tree rproto, x;
for (rproto = rproto_list; rproto; rproto = TREE_CHAIN (rproto))
{
tree p = TREE_VALUE (rproto);
if (TREE_CODE (p) == PROTOCOL_INTERFACE_TYPE)
{
if ((x = lookup_property_in_list (p, property)))
return x;
if (PROTOCOL_LIST (p))
return lookup_property_in_protocol_list (PROTOCOL_LIST (p), property);
}
else
{
; /* An identifier...if we could not find a protocol. */
}
}
return NULL_TREE;
}
/* This routine looks up the PROPERTY in current INTERFACE, its categories and up the
chain of interface hierarchy. */
static tree
lookup_property (tree interface_type, tree property)
{
tree inter = interface_type;
while (inter)
{
tree x, category;
if ((x = lookup_property_in_list (inter, property)))
return x;
/* Failing that, look for the property in each category of the class. */
category = inter;
while ((category = CLASS_CATEGORY_LIST (category)))
{
if ((x = lookup_property_in_list (category, property)))
return x;
/* When checking a category, also check the protocols
attached with the category itself. */
if (CLASS_PROTOCOL_LIST (category)
&& (x = lookup_property_in_protocol_list
(CLASS_PROTOCOL_LIST (category), property)))
return x;
}
/* Failing to find in categories, look for property in protocol list. */
if (CLASS_PROTOCOL_LIST (inter)
&& (x = lookup_property_in_protocol_list
(CLASS_PROTOCOL_LIST (inter), property)))
return x;
/* Failing that, climb up the inheritance hierarchy. */
inter = lookup_interface (CLASS_SUPER_NAME (inter));
}
return inter;
}
/* This routine returns a PROPERTY_KIND for the front end RID code supplied. */
enum objc_property_attribute_kind
objc_prop_attr_kind_for_rid (enum rid prop_rid)
{
switch (prop_rid)
{
default: return OBJC_PROPERTY_ATTR_UNKNOWN;
case RID_GETTER: return OBJC_PROPERTY_ATTR_GETTER;
case RID_SETTER: return OBJC_PROPERTY_ATTR_SETTER;
case RID_READONLY: return OBJC_PROPERTY_ATTR_READONLY;
case RID_READWRITE: return OBJC_PROPERTY_ATTR_READWRITE;
case RID_ASSIGN: return OBJC_PROPERTY_ATTR_ASSIGN;
case RID_RETAIN: return OBJC_PROPERTY_ATTR_RETAIN;
case RID_COPY: return OBJC_PROPERTY_ATTR_COPY;
case RID_PROPATOMIC: return OBJC_PROPERTY_ATTR_ATOMIC;
case RID_NONATOMIC: return OBJC_PROPERTY_ATTR_NONATOMIC;
case RID_NULL_UNSPECIFIED:return OBJC_PROPERTY_ATTR_NULL_UNSPECIFIED;
case RID_NULLABLE: return OBJC_PROPERTY_ATTR_NULLABLE;
case RID_NONNULL: return OBJC_PROPERTY_ATTR_NONNULL;
case RID_NULL_RESETTABLE: return OBJC_PROPERTY_ATTR_NULL_RESETTABLE;
case RID_CLASS: return OBJC_PROPERTY_ATTR_CLASS;
}
}
/* This routine is called by the parser when a
@property... declaration is found. 'decl' is the declaration of
the property (type/identifier), and the other arguments represent
property attributes that may have been specified in the Objective-C
declaration. 'parsed_property_readonly' is 'true' if the attribute
'readonly' was specified, and 'false' if not; similarly for the
other bool parameters. 'property_getter_ident' is NULL_TREE
if the attribute 'getter' was not specified, and is the identifier
corresponding to the specified getter if it was; similarly for
'property_setter_ident'. */
void
objc_add_property_declaration (location_t location, tree decl,
vec<property_attribute_info *>& prop_attr_list)
{
if (flag_objc1_only)
/* FIXME: we probably ought to bail out at this point. */
error_at (location, "%<@property%> is not available in Objective-C 1.0");
/* We must be in an interface, category, or protocol. */
if (!objc_interface_context)
{
error_at (location, "property declaration not in %<@interface%>,"
" %<@protocol%> or %<category%> context");
return;
}
/* Do some spot-checks for the most obvious invalid cases. */
gcc_checking_assert (decl && TREE_CODE (decl) == FIELD_DECL);
if (decl && !DECL_NAME (decl))
{
error_at (location, "properties must be named");
return;
}
location_t decl_loc = DECL_SOURCE_LOCATION (decl);
decl_loc = make_location (decl_loc, location, decl_loc);
if (TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE)
{
error_at (decl_loc, "property cannot be an array");
return;
}
if (DECL_C_BIT_FIELD (decl))
{
/* A @property is not an actual variable, but it is a way to
describe a pair of accessor methods, so its type (which is
the type of the return value of the getter and the first
argument of the setter) can't be a bitfield (as return values
and arguments of functions cannot be bitfields). The
underlying instance variable could be a bitfield, but that is
a different matter. */
error_at (decl_loc, "property cannot be a bit-field");
return;
}
/* The final results of parsing the (growing number) of property
attributes. */
property_attribute_info *attrs[OBJC_PROPATTR_GROUP_MAX] = { nullptr };
tree property_getter_ident = NULL_TREE;
tree property_setter_ident = NULL_TREE;
for (unsigned pn = 0; pn < prop_attr_list.length (); ++pn)
{
if (prop_attr_list[pn]->parse_error)
continue; /* Ignore attributes known to be wrongly parsed. */
switch (int g = (int) prop_attr_list[pn]->group())
{
case OBJC_PROPATTR_GROUP_UNKNOWN:
continue;
case OBJC_PROPATTR_GROUP_SETTER:
case OBJC_PROPATTR_GROUP_GETTER:
if (attrs[g])
{
warning_at (prop_attr_list[pn]->prop_loc, OPT_Wattributes,
"multiple property %qE methods specified, the latest"
" one will be used", attrs[g]->name);
inform (attrs[g]->prop_loc, "previous specification");
}
attrs[g] = prop_attr_list[pn];
if (g == OBJC_PROPATTR_GROUP_SETTER)
property_setter_ident = attrs[g]->ident;
else
property_getter_ident = attrs[g]->ident;
continue;
default:
{
if (!attrs[g])
;
else if (attrs[g]->prop_kind != prop_attr_list[pn]->prop_kind)
{
error_at (prop_attr_list[pn]->prop_loc,
"%qE attribute conflicts with %qE attribute",
prop_attr_list[pn]->name, attrs[g]->name);
inform (attrs[g]->prop_loc, "%qE specified here",
attrs[g]->name );
}
else
{
warning_at (prop_attr_list[pn]->prop_loc, OPT_Wattributes,
"duplicate %qE attribute", attrs[g]->name);
inform (attrs[g]->prop_loc, "first specified here");
}
attrs[g] = prop_attr_list[pn];
}
continue;
}
}
/* The defaults for atomicity (atomic) and write-ability (readwrite) apply
even if the user provides no specified attributes. */
bool property_nonatomic = false;
bool property_readonly = false;
/* Set the values from any specified by the user; these are easy, only two
states. */
if (attrs[OBJC_PROPATTR_GROUP_ATOMIC])
property_nonatomic = attrs[OBJC_PROPATTR_GROUP_ATOMIC]->prop_kind
== OBJC_PROPERTY_ATTR_NONATOMIC;
if (attrs[OBJC_PROPATTR_GROUP_READWRITE])
property_readonly = attrs[OBJC_PROPATTR_GROUP_READWRITE]->prop_kind
== OBJC_PROPERTY_ATTR_READONLY;
/* One can't set a readonly value; we issue an error, but force the property
to readwrite as well. */
if (property_readonly && property_setter_ident)
{
error_at (attrs[OBJC_PROPATTR_GROUP_READWRITE]->prop_loc, "%<readonly%>"
" attribute conflicts with %<setter%> attribute");
gcc_checking_assert (attrs[OBJC_PROPATTR_GROUP_SETTER]);
inform (attrs[OBJC_PROPATTR_GROUP_SETTER]->prop_loc, "%<setter%>"
" specified here");
property_readonly = false;
}
/* Assign semantics is a tri-state property, and also needs some further
checking against the object type. */
objc_property_assign_semantics property_assign_semantics
= OBJC_PROPERTY_ASSIGN;
if (attrs[OBJC_PROPATTR_GROUP_ASSIGN])
{
if (attrs[OBJC_PROPATTR_GROUP_ASSIGN]->prop_kind
== OBJC_PROPERTY_ATTR_ASSIGN)
property_assign_semantics = OBJC_PROPERTY_ASSIGN;
else if (attrs[OBJC_PROPATTR_GROUP_ASSIGN]->prop_kind
== OBJC_PROPERTY_ATTR_RETAIN)
property_assign_semantics = OBJC_PROPERTY_RETAIN;
else if (attrs[OBJC_PROPATTR_GROUP_ASSIGN]->prop_kind
== OBJC_PROPERTY_ATTR_COPY)
property_assign_semantics = OBJC_PROPERTY_COPY;
else
gcc_unreachable ();
}
/* An attribute that indicates this property manipulates a class variable.
In this case, both the variable and the getter/setter must be provided
by the user. */
bool property_class = false;
if (attrs[OBJC_PROPATTR_GROUP_CLASS])
property_nonatomic = attrs[OBJC_PROPATTR_GROUP_CLASS]->prop_kind
== OBJC_PROPERTY_ATTR_CLASS;
/* Nullability specifications for the property. */
enum objc_property_nullability property_nullability
= OBJC_PROPERTY_NULL_UNSET;
if (attrs[OBJC_PROPATTR_GROUP_NULLABLE])
{
if (attrs[OBJC_PROPATTR_GROUP_NULLABLE]->prop_kind
== OBJC_PROPERTY_ATTR_NULL_UNSPECIFIED)
property_nullability = OBJC_PROPERTY_NULL_UNSPECIFIED;
else if (attrs[OBJC_PROPATTR_GROUP_NULLABLE]->prop_kind
== OBJC_PROPERTY_ATTR_NULLABLE)
property_nullability = OBJC_PROPERTY_NULLABLE;
else if (attrs[OBJC_PROPATTR_GROUP_NULLABLE]->prop_kind
== OBJC_PROPERTY_ATTR_NONNULL)
property_nullability = OBJC_PROPERTY_NONNULL;
else if (attrs[OBJC_PROPATTR_GROUP_NULLABLE]->prop_kind
== OBJC_PROPERTY_ATTR_NULL_RESETTABLE)
property_nullability = OBJC_PROPERTY_NULL_RESETTABLE;
else
gcc_unreachable ();
}
/* TODO: Check that the property type is an Objective-C object or a
"POD". */
/* Implement -Wproperty-assign-default (which is enabled by default). */
if (warn_property_assign_default
/* If garbage collection is not being used, then 'assign' is
valid for objects (and typically used for delegates) but it
is wrong in most cases (since most objects need to be
retained or copied in setters). Warn users when 'assign' is
used implicitly. */
&& property_assign_semantics == OBJC_PROPERTY_ASSIGN
/* Read-only properties are never assigned, so the assignment
semantics do not matter in that case. */
&& !property_readonly
&& !flag_objc_gc)
{
/* Please note that it would make sense to default to 'assign'
for non-{Objective-C objects}, and to 'retain' for
Objective-C objects. But that would break compatibility with
other compilers. */
if (!attrs[OBJC_PROPATTR_GROUP_ASSIGN])
{
/* Use 'false' so we do not warn for Class objects. */
if (objc_type_valid_for_messaging (TREE_TYPE (decl), false))
{
warning_at (decl_loc, 0, "object property %qD has no %<assign%>,"
" %<retain%> or %<copy%> attribute; assuming"
" %<assign%>", decl);
inform (decl_loc, "%<assign%> can be unsafe for Objective-C"
" objects; please state explicitly if you need it");
}
}
}
/* Some attributes make no sense unless applied to an Objective-C object. */
bool prop_objc_object_p
= objc_type_valid_for_messaging (TREE_TYPE (decl), true);
if (!prop_objc_object_p)
{
tree p_name = NULL_TREE;
if (property_assign_semantics == OBJC_PROPERTY_RETAIN
|| property_assign_semantics == OBJC_PROPERTY_COPY)
p_name = attrs[OBJC_PROPATTR_GROUP_ASSIGN]->name;
if (p_name)
error_at (decl_loc, "%qE attribute is only valid for Objective-C"
" objects", p_name);
}
/* Now determine the final property getter and setter names. They
will be stored in the PROPERTY_DECL, from which they'll always be
extracted and used. */
/* Adjust, or fill in, setter and getter names. We overwrite the
property_setter_ident and property_getter_ident
with the final setter and getter identifiers that will be
used. */
if (property_setter_ident)
{
/* The setter should be terminated by ':', but the parser only
gives us an identifier without ':'. So, we need to add ':'
at the end. */
const char *parsed_setter = IDENTIFIER_POINTER (property_setter_ident);
size_t length = strlen (parsed_setter);
char *final_setter = (char *)alloca (length + 2);
sprintf (final_setter, "%s:", parsed_setter);
property_setter_ident = get_identifier (final_setter);
}
else
{
if (!property_readonly)
property_setter_ident = get_identifier (objc_build_property_setter_name
(DECL_NAME (decl)));
}
if (!property_getter_ident)
property_getter_ident = DECL_NAME (decl);
/* Check for duplicate property declarations. We first check the
immediate context for a property with the same name. Any such
declarations are an error, unless this is a class extension and
we are extending a property from readonly to readwrite. */
bool property_extension_in_class_extension = false;
tree x = NULL_TREE;
for (x = CLASS_PROPERTY_DECL (objc_interface_context); x; x = TREE_CHAIN (x))
{
if (PROPERTY_NAME (x) == DECL_NAME (decl))
{
if (objc_in_class_extension
&& !property_readonly
&& PROPERTY_READONLY (x) == 1)
{
/* This is a class extension, and we are extending an
existing readonly property to a readwrite one.
That's fine. :-) */
property_extension_in_class_extension = true;
break;
}
else
{
location_t original_location = DECL_SOURCE_LOCATION (x);
error_at (location, "redeclaration of property %qD", decl);
if (original_location != UNKNOWN_LOCATION)
inform (original_location, "originally specified here");
return;
}
}
}
/* If x is not NULL_TREE, we must be in a class extension and we're
extending a readonly property. In that case, no point in
searching for another declaration. */
if (x == NULL_TREE)
{
/* We now need to check for existing property declarations (in
the superclass, other categories or protocols) and check that
the new declaration is not in conflict with existing
ones. */
/* Search for a previous, existing declaration of a property
with the same name in superclasses, protocols etc. If one is
found, it will be in the 'x' variable. */
/* Note that, for simplicity, the following may search again the
local context. That's Ok as nothing will be found (else we'd
have thrown an error above); it's only a little inefficient,
but the code is simpler. */
switch (TREE_CODE (objc_interface_context))
{
case CLASS_INTERFACE_TYPE:
/* Look up the property in the current @interface (which
will find nothing), then its protocols and categories and
superclasses. */
x = lookup_property (objc_interface_context, DECL_NAME (decl));
break;
case CATEGORY_INTERFACE_TYPE:
/* Look up the property in the main @interface, then
protocols and categories (one of them is ours, and will
find nothing) and superclasses. */
x = lookup_property (lookup_interface (CLASS_NAME (objc_interface_context)),
DECL_NAME (decl));
break;
case PROTOCOL_INTERFACE_TYPE:
/* Looks up the property in any protocols attached to the
current protocol. */
if (PROTOCOL_LIST (objc_interface_context))
{
x = lookup_property_in_protocol_list (PROTOCOL_LIST (objc_interface_context),
DECL_NAME (decl));
}
break;
default:
gcc_unreachable ();
}
}
if (x != NULL_TREE)
{
/* An existing property was found; check that it has the same
types, or it is compatible. */
location_t original_location = DECL_SOURCE_LOCATION (x);
if (PROPERTY_NONATOMIC (x) != property_nonatomic)
{
warning_at (location, 0,
"%<nonatomic%> attribute of property %qD conflicts with "
"previous declaration", decl);
if (original_location != UNKNOWN_LOCATION)
inform (original_location, "originally specified here");
return;
}
if (PROPERTY_GETTER_NAME (x) != property_getter_ident)
{
warning_at (location, 0,
"%<getter%> attribute of property %qD conflicts with "
"previous declaration", decl);
if (original_location != UNKNOWN_LOCATION)
inform (original_location, "originally specified here");
return;
}
/* We can only compare the setter names if both the old and new property have a setter. */
if (!property_readonly && !PROPERTY_READONLY(x))
{
if (PROPERTY_SETTER_NAME (x) != property_setter_ident)
{
warning_at (location, 0,
"%<setter%> attribute of property %qD conflicts with "
"previous declaration", decl);
if (original_location != UNKNOWN_LOCATION)
inform (original_location, "originally specified here");
return;
}
}
if (PROPERTY_ASSIGN_SEMANTICS (x) != property_assign_semantics)
{
warning_at (location, 0,
"assign semantics attributes of property %qD conflict with previous declaration", decl);
if (original_location != UNKNOWN_LOCATION)
inform (original_location, "originally specified here");
return;
}
/* It's ok to have a readonly property that becomes a readwrite, but not vice versa. */
if (PROPERTY_READONLY (x) == 0 && property_readonly == 1)
{
warning_at (location, 0,
"%<readonly%> attribute of property %qD conflicts with "
"previous declaration", decl);
if (original_location != UNKNOWN_LOCATION)
inform (original_location, "originally specified here");
return;
}
/* We now check that the new and old property declarations have
the same types (or compatible one). In the Objective-C
tradition of loose type checking, we do type-checking but
only generate warnings (not errors) if they do not match.
For non-readonly properties, the types must match exactly;
for readonly properties, it is allowed to use a "more
specialized" type in the new property declaration. Eg, the
superclass has a getter returning (NSArray *) and the
subclass a getter returning (NSMutableArray *). The object's
getter returns an (NSMutableArray *); but if you cast the
object to the superclass, which is allowed, you'd still
expect the getter to return an (NSArray *), which works since
an (NSMutableArray *) is an (NSArray *) too. So, the set of
objects belonging to the type of the new @property should be
a subset of the set of objects belonging to the type of the
old @property. This is what "specialization" means. And the
reason it only applies to readonly properties is that for a
readwrite property the setter would have the opposite
requirement - ie that the superclass type is more specialized
then the subclass one; hence the only way to satisfy both
constraints is that the types match. */
/* If the types are not the same in the C sense, we warn ... */
if (!comptypes (TREE_TYPE (x), TREE_TYPE (decl))
/* ... unless the property is readonly, in which case we
allow a new, more specialized, declaration. */
&& (!property_readonly
|| !objc_compare_types (TREE_TYPE (x),
TREE_TYPE (decl), -5, NULL_TREE)))
{
warning_at (location, 0,
"type of property %qD conflicts with previous declaration", decl);
if (original_location != UNKNOWN_LOCATION)
inform (original_location, "originally specified here");
return;
}
/* If we are in a class extension and we're extending a readonly
property in the main @interface, we'll just update the
existing property with the readwrite flag and potentially the
new setter name. */
if (property_extension_in_class_extension)
{
PROPERTY_READONLY (x) = 0;
PROPERTY_SETTER_NAME (x) = property_setter_ident;
return;
}
}
/* Create a PROPERTY_DECL node. */
tree property_decl = make_node (PROPERTY_DECL);
/* Copy the basic information from the original decl. */
tree p_type = TREE_TYPE (decl);
TREE_TYPE (property_decl) = p_type;
DECL_SOURCE_LOCATION (property_decl) = DECL_SOURCE_LOCATION (decl);
TREE_DEPRECATED (property_decl) = TREE_DEPRECATED (decl);
TREE_UNAVAILABLE (property_decl) = TREE_UNAVAILABLE (decl);
/* Add property-specific information. */
PROPERTY_NAME (property_decl) = DECL_NAME (decl);
PROPERTY_GETTER_NAME (property_decl) = property_getter_ident;
PROPERTY_SETTER_NAME (property_decl) = property_setter_ident;
PROPERTY_READONLY (property_decl) = property_readonly;
PROPERTY_NONATOMIC (property_decl) = property_nonatomic;
PROPERTY_CLASS (property_decl) = property_class;
PROPERTY_ASSIGN_SEMANTICS (property_decl) = property_assign_semantics;
PROPERTY_IVAR_NAME (property_decl) = NULL_TREE;
PROPERTY_DYNAMIC (property_decl) = 0;
/* FIXME: We seem to drop any existing DECL_ATTRIBUTES on the floor. */
if (property_nullability != OBJC_PROPERTY_NULL_UNSET)
{
if (p_type && !POINTER_TYPE_P (p_type))
error_at (decl_loc, "nullability specifier %qE cannot be applied to"
" non-pointer type %qT",
attrs[OBJC_PROPATTR_GROUP_NULLABLE]->name, p_type);
else if (p_type && POINTER_TYPE_P (p_type) && TREE_TYPE (p_type)
&& POINTER_TYPE_P (TREE_TYPE (p_type)))
error_at (decl_loc, "nullability specifier %qE cannot be applied to"
" multi-level pointer type %qT",
attrs[OBJC_PROPATTR_GROUP_NULLABLE]->name, p_type);
else
{
tree attr_name = get_identifier ("objc_nullability");
tree attr_value = build_int_cst (unsigned_type_node,
(unsigned)property_nullability);
tree nulla = build_tree_list (attr_name, attr_value);
DECL_ATTRIBUTES (property_decl) = nulla;
}
}
/* Remember the fact that the property was found in the @optional
section in a @protocol, or not. */
if (objc_method_optional_flag)
PROPERTY_OPTIONAL (property_decl) = 1;
else
PROPERTY_OPTIONAL (property_decl) = 0;
/* Note that PROPERTY_GETTER_NAME is always set for all
PROPERTY_DECLs, and PROPERTY_SETTER_NAME is always set for all
PROPERTY_DECLs where PROPERTY_READONLY == 0. Any time we deal
with a getter or setter, we should get the PROPERTY_DECL and use
PROPERTY_GETTER_NAME and PROPERTY_SETTER_NAME to know the correct
names. */
/* Add the PROPERTY_DECL to the list of properties for the class. */
TREE_CHAIN (property_decl) = CLASS_PROPERTY_DECL (objc_interface_context);
CLASS_PROPERTY_DECL (objc_interface_context) = property_decl;
}
/* This is a subroutine of objc_maybe_build_component_ref. Search the
list of methods in the interface (and, failing that, the local list
in the implementation, and failing that, the protocol list)
provided for a 'setter' or 'getter' for 'component' with default
names (ie, if 'component' is "name", then search for "name" and
"setName:"). It is also possible to specify a different
'getter_name' (this is used for @optional readonly properties). If
any is found, then create an artificial property that uses them.
Return NULL_TREE if 'getter' or 'setter' could not be found. */
static tree
maybe_make_artificial_property_decl (tree interface, tree implementation,
tree protocol_list, tree component, bool is_class,
tree getter_name)
{
tree setter_name = get_identifier (objc_build_property_setter_name (component));
tree getter = NULL_TREE;
tree setter = NULL_TREE;
if (getter_name == NULL_TREE)
getter_name = component;
/* First, check the @interface and all superclasses. */
if (interface)
{
int flags = 0;
/* Using instance methods of the root class as accessors is most
likely unwanted and can be extremely confusing (and, most
importantly, other Objective-C 2.0 compilers do not do it).
Turn it off. */
if (is_class)
flags = OBJC_LOOKUP_CLASS | OBJC_LOOKUP_NO_INSTANCE_METHODS_OF_ROOT_CLASS;
getter = lookup_method_static (interface, getter_name, flags);
setter = lookup_method_static (interface, setter_name, flags);
}
/* Second, check the local @implementation context. */
if (!getter && !setter)
{
if (implementation)
{
if (is_class)
{
getter = lookup_method (CLASS_CLS_METHODS (implementation), getter_name);
setter = lookup_method (CLASS_CLS_METHODS (implementation), setter_name);
}
else
{
getter = lookup_method (CLASS_NST_METHODS (implementation), getter_name);
setter = lookup_method (CLASS_NST_METHODS (implementation), setter_name);
}
}
}
/* Try the protocol_list if we didn't find anything in the
@interface and in the @implementation. */
if (!getter && !setter)
{
getter = lookup_method_in_protocol_list (protocol_list, getter_name, is_class);
setter = lookup_method_in_protocol_list (protocol_list, setter_name, is_class);
}
/* There needs to be at least a getter or setter for this to be a
valid 'object.component' syntax. */
if (getter || setter)
{
/* Yes ... determine the type of the expression. */
tree property_decl;
tree type;
if (getter)
type = TREE_VALUE (TREE_TYPE (getter));
else
type = TREE_VALUE (TREE_TYPE (METHOD_SEL_ARGS (setter)));
/* Create an artificial property declaration with the
information we collected on the type and getter/setter
names. */
property_decl = make_node (PROPERTY_DECL);
TREE_TYPE (property_decl) = type;
DECL_SOURCE_LOCATION (property_decl) = input_location;
TREE_DEPRECATED (property_decl) = 0;
TREE_UNAVAILABLE (property_decl) = 0;
DECL_ARTIFICIAL (property_decl) = 1;
/* Add property-specific information. Note that one of
PROPERTY_GETTER_NAME or PROPERTY_SETTER_NAME may refer to a
non-existing method; this will generate an error when the
expression is later compiled. At this stage we don't know if
the getter or setter will be used, so we can't generate an
error. */
PROPERTY_NAME (property_decl) = component;
PROPERTY_GETTER_NAME (property_decl) = getter_name;
PROPERTY_SETTER_NAME (property_decl) = setter_name;
PROPERTY_READONLY (property_decl) = 0;
PROPERTY_NONATOMIC (property_decl) = 0;
PROPERTY_ASSIGN_SEMANTICS (property_decl) = 0;
PROPERTY_IVAR_NAME (property_decl) = NULL_TREE;
PROPERTY_DYNAMIC (property_decl) = 0;
PROPERTY_OPTIONAL (property_decl) = 0;
if (!getter)
PROPERTY_HAS_NO_GETTER (property_decl) = 1;
/* The following is currently unused, but it's nice to have
there. We may use it if we need in the future. */
if (!setter)
PROPERTY_HAS_NO_SETTER (property_decl) = 1;
return property_decl;
}
return NULL_TREE;
}
/* This hook routine is invoked by the parser when an expression such
as 'xxx.yyy' is parsed. We get a chance to process these
expressions in a way that is specified to Objective-C (to implement
the Objective-C 2.0 dot-syntax, properties, or non-fragile ivars).
If the expression is not an Objective-C specified expression, we
should return NULL_TREE; else we return the expression.
At the moment this only implements dot-syntax and properties (not
non-fragile ivars yet), ie 'object.property' or 'object.component'
where 'component' is not a declared property, but a valid getter or
setter for it could be found. */
tree
objc_maybe_build_component_ref (tree object, tree property_ident)
{
tree x = NULL_TREE;
tree rtype;
/* If we are in Objective-C 1.0 mode, dot-syntax and properties are
not available. */
if (flag_objc1_only)
return NULL_TREE;
/* Try to determine if 'object' is an Objective-C object or not. If
not, return. */
if (object == NULL_TREE || object == error_mark_node
|| (rtype = TREE_TYPE (object)) == NULL_TREE)
return NULL_TREE;
if (property_ident == NULL_TREE || property_ident == error_mark_node
|| TREE_CODE (property_ident) != IDENTIFIER_NODE)
return NULL_TREE;
/* The following analysis of 'object' is similar to the one used for
the 'receiver' of a method invocation. We need to determine what
'object' is and find the appropriate property (either declared,
or artificial) for it (in the same way as we need to find the
appropriate method prototype for a method invocation). There are
some simplifications here though: "object.property" is invalid if
"object" has a type of "id" or "Class"; it must at least have a
protocol attached to it, and "object" is never a class name as
that is done by objc_build_class_component_ref. Finally, we
don't know if this really is a dot-syntax expression, so we want
to make a quick exit if it is not; for this reason, we try to
postpone checks after determining that 'object' looks like an
Objective-C object. */
if (objc_is_id (rtype))
{
/* This is the case that the 'object' is of type 'id' or
'Class'. */
/* Check if at least it is of type 'id <Protocol>' or 'Class
<Protocol>'; if so, look the property up in the
protocols. */
if (TYPE_HAS_OBJC_INFO (TREE_TYPE (rtype)))
{
tree rprotos = TYPE_OBJC_PROTOCOL_LIST (TREE_TYPE (rtype));
if (rprotos)
{
/* No point looking up declared @properties if we are
dealing with a class. Classes have no declared
properties. */
if (!IS_CLASS (rtype))
x = lookup_property_in_protocol_list (rprotos, property_ident);
if (x == NULL_TREE)
{
/* Ok, no property. Maybe it was an
object.component dot-syntax without a declared
property (this is valid for classes too). Look
for getter/setter methods and internally declare
an artificial property based on them if found. */
x = maybe_make_artificial_property_decl (NULL_TREE,
NULL_TREE,
rprotos,
property_ident,
IS_CLASS (rtype),
NULL_TREE);
}
else if (PROPERTY_OPTIONAL (x) && PROPERTY_READONLY (x))
{
/* This is a special, complicated case. If the
property is optional, and is read-only, then the
property is always used for reading, but an
eventual existing non-property setter can be used
for writing. We create an artificial property
decl copying the getter from the optional
property, and looking up the setter in the
interface. */
x = maybe_make_artificial_property_decl (NULL_TREE,
NULL_TREE,
rprotos,
property_ident,
false,
PROPERTY_GETTER_NAME (x));
}
}
}
else if (objc_method_context)
{
/* Else, if we are inside a method it could be the case of
'super' or 'self'. */
tree interface_type = NULL_TREE;
tree t = object;
while (TREE_CODE (t) == COMPOUND_EXPR
|| TREE_CODE (t) == MODIFY_EXPR
|| CONVERT_EXPR_P (t)
|| TREE_CODE (t) == COMPONENT_REF)
t = TREE_OPERAND (t, 0);
STRIP_ANY_LOCATION_WRAPPER (t);
if (t == UOBJC_SUPER_decl)
interface_type = lookup_interface (CLASS_SUPER_NAME (implementation_template));
else if (t == self_decl)
interface_type = lookup_interface (CLASS_NAME (implementation_template));
if (interface_type)
{
if (TREE_CODE (objc_method_context) != CLASS_METHOD_DECL)
x = lookup_property (interface_type, property_ident);
if (x == NULL_TREE)
{
/* Try the dot-syntax without a declared property.
If this is an access to 'self', it is possible
that they may refer to a setter/getter that is
not declared in the interface, but exists locally
in the implementation. In that case, get the
implementation context and use it. */
tree implementation = NULL_TREE;
if (t == self_decl)
implementation = objc_implementation_context;
x = maybe_make_artificial_property_decl
(interface_type, implementation, NULL_TREE,
property_ident,
(TREE_CODE (objc_method_context) == CLASS_METHOD_DECL),
NULL_TREE);
}
else if (PROPERTY_OPTIONAL (x) && PROPERTY_READONLY (x))
{
tree implementation = NULL_TREE;
if (t == self_decl)
implementation = objc_implementation_context;
x = maybe_make_artificial_property_decl (interface_type,
implementation,
NULL_TREE,
property_ident,
false,
PROPERTY_GETTER_NAME (x));
}
}
}
}
else
{
/* This is the case where we have more information on 'rtype'. */
tree basetype = TYPE_MAIN_VARIANT (rtype);
/* Skip the pointer - if none, it's not an Objective-C object or
class. */
if (basetype != NULL_TREE && TREE_CODE (basetype) == POINTER_TYPE)
basetype = TREE_TYPE (basetype);
else
return NULL_TREE;
/* Traverse typedefs. */
while (basetype != NULL_TREE
&& TREE_CODE (basetype) == RECORD_TYPE
&& OBJC_TYPE_NAME (basetype)
&& TREE_CODE (OBJC_TYPE_NAME (basetype)) == TYPE_DECL
&& DECL_ORIGINAL_TYPE (OBJC_TYPE_NAME (basetype)))
basetype = DECL_ORIGINAL_TYPE (OBJC_TYPE_NAME (basetype));
if (basetype != NULL_TREE && TYPED_OBJECT (basetype))
{
tree interface_type = TYPE_OBJC_INTERFACE (basetype);
tree protocol_list = TYPE_OBJC_PROTOCOL_LIST (basetype);
if (interface_type
&& (TREE_CODE (interface_type) == CLASS_INTERFACE_TYPE
|| TREE_CODE (interface_type) == CATEGORY_INTERFACE_TYPE
|| TREE_CODE (interface_type) == PROTOCOL_INTERFACE_TYPE))
{
/* Not sure 'rtype' could ever be a class here! Just
for safety we keep the checks. */
if (!IS_CLASS (rtype))
{
x = lookup_property (interface_type, property_ident);
if (x == NULL_TREE)
x = lookup_property_in_protocol_list (protocol_list,
property_ident);
}
if (x == NULL_TREE)
{
/* Try the dot-syntax without a declared property.
If we are inside a method implementation, it is
possible that they may refer to a setter/getter
that is not declared in the interface, but exists
locally in the implementation. In that case, get
the implementation context and use it. */
tree implementation = NULL_TREE;
if (objc_implementation_context
&& CLASS_NAME (objc_implementation_context)
== OBJC_TYPE_NAME (interface_type))
implementation = objc_implementation_context;
x = maybe_make_artificial_property_decl (interface_type,
implementation,
protocol_list,
property_ident,
IS_CLASS (rtype),
NULL_TREE);
}
else if (PROPERTY_OPTIONAL (x) && PROPERTY_READONLY (x))
{
tree implementation = NULL_TREE;
if (objc_implementation_context
&& CLASS_NAME (objc_implementation_context)
== OBJC_TYPE_NAME (interface_type))
implementation = objc_implementation_context;
x = maybe_make_artificial_property_decl (interface_type,
implementation,
protocol_list,
property_ident,
false,
PROPERTY_GETTER_NAME (x));
}
}
}
}
if (x)
{
tree expression;
tree getter_call;
tree method_prototype_avail = NULL_TREE;
/* We have an additional nasty problem here; if this
PROPERTY_REF needs to become a 'getter', then the conversion
from PROPERTY_REF into a getter call happens in gimplify,
after the selector table has already been generated and when
it is too late to add another selector to it. To work around
the problem, we always create the getter call at this stage,
which puts the selector in the table. Note that if the
PROPERTY_REF becomes a 'setter' instead of a 'getter', then
we have added a selector too many to the selector table.
This is a little inefficient.
Also note that method calls to 'self' and 'super' require the
context (self_decl, UOBJS_SUPER_decl,
objc_implementation_context etc) to be built correctly; this
is yet another reason why building the call at the gimplify
stage (when this context has been lost) is not very
practical. If we build it at this stage, we know it will
always be built correctly.
If the PROPERTY_HAS_NO_GETTER() (ie, it is an artificial
property decl created to deal with a dotsyntax not really
referring to an existing property) then do not try to build a
call to the getter as there is no getter. */
if (PROPERTY_HAS_NO_GETTER (x))
getter_call = NULL_TREE;
else
getter_call = objc_finish_message_expr
(object, PROPERTY_GETTER_NAME (x), NULL_TREE,
/* Disable the immediate deprecation warning if the getter
is deprecated, but record the fact that the getter is
deprecated by setting PROPERTY_REF_DEPRECATED_GETTER to
the method prototype. */
&method_prototype_avail);
expression = build4 (PROPERTY_REF, TREE_TYPE(x), object, x, getter_call,
method_prototype_avail);
SET_EXPR_LOCATION (expression, input_location);
TREE_SIDE_EFFECTS (expression) = 1;
return expression;
}
return NULL_TREE;
}
/* This hook routine is invoked by the parser when an expression such
as 'xxx.yyy' is parsed, and 'xxx' is a class name. This is the
Objective-C 2.0 dot-syntax applied to classes, so we need to
convert it into a setter/getter call on the class. */
tree
objc_build_class_component_ref (tree class_name, tree property_ident)
{
tree x = NULL_TREE;
tree object, rtype;
if (flag_objc1_only)
error_at (input_location, "the dot syntax is not available in Objective-C 1.0");
if (class_name == NULL_TREE || class_name == error_mark_node
|| TREE_CODE (class_name) != IDENTIFIER_NODE)
return error_mark_node;
if (property_ident == NULL_TREE || property_ident == error_mark_node
|| TREE_CODE (property_ident) != IDENTIFIER_NODE)
return NULL_TREE;
object = objc_get_class_reference (class_name);
if (!object)
{
/* We know that 'class_name' is an Objective-C class name as the
parser won't call this function if it is not. This is only a
double-check for safety. */
error_at (input_location, "could not find class %qE", class_name);
return error_mark_node;
}
rtype = lookup_interface (class_name);
if (!rtype)
{
/* Again, this should never happen, but we do check. */
error_at (input_location, "could not find interface for class %qE", class_name);
return error_mark_node;
}
else
{
if (TREE_UNAVAILABLE (rtype))
error ("class %qE is unavailable", class_name);
else if (TREE_DEPRECATED (rtype))
warning (OPT_Wdeprecated_declarations, "class %qE is deprecated", class_name);
}
x = maybe_make_artificial_property_decl (rtype, NULL_TREE, NULL_TREE,
property_ident,
true, NULL_TREE);
if (x)
{
tree expression;
tree getter_call;
tree method_prototype_avail = NULL_TREE;
if (PROPERTY_HAS_NO_GETTER (x))
getter_call = NULL_TREE;
else
getter_call = objc_finish_message_expr
(object, PROPERTY_GETTER_NAME (x), NULL_TREE,
&method_prototype_avail);
expression = build4 (PROPERTY_REF, TREE_TYPE(x), object, x, getter_call,
method_prototype_avail);
SET_EXPR_LOCATION (expression, input_location);
TREE_SIDE_EFFECTS (expression) = 1;
return expression;
}
else
{
error_at (input_location, "could not find setter/getter for %qE in class %qE",
property_ident, class_name);
return error_mark_node;
}
return NULL_TREE;
}
/* This is used because we don't want to expose PROPERTY_REF to the
C/C++ frontends. Maybe we should! */
bool
objc_is_property_ref (tree node)
{
if (node && TREE_CODE (node) == PROPERTY_REF)
return true;
else
return false;
}
/* We use this to report tree codes that are known to be invalid in const-
expression contexts. */
bool
objc_non_constant_expr_p (tree node)
{
switch (TREE_CODE (node))
{
default:
return false;
case MESSAGE_SEND_EXPR:
case PROPERTY_REF:
return true;
}
}
/* This function builds a setter call for a PROPERTY_REF (real, for a
declared property, or artificial, for a dot-syntax accessor which
is not corresponding to a property). 'lhs' must be a PROPERTY_REF
(the caller must check this beforehand). 'rhs' is the value to
assign to the property. A plain setter call is returned, or
error_mark_node if the property is readonly. */
static tree
objc_build_setter_call (tree lhs, tree rhs)
{
tree object_expr = PROPERTY_REF_OBJECT (lhs);
tree property_decl = PROPERTY_REF_PROPERTY_DECL (lhs);
if (PROPERTY_READONLY (property_decl))
{
error ("%qs property cannot be set", "readonly");
return error_mark_node;
}
else
{
tree setter_argument = build_tree_list (NULL_TREE, rhs);
tree setter;
/* TODO: Check that the setter return type is 'void'. */
/* TODO: Decay arguments in C. */
setter = objc_finish_message_expr (object_expr,
PROPERTY_SETTER_NAME (property_decl),
setter_argument, NULL);
return setter;
}
/* Unreachable, but the compiler may not realize. */
return error_mark_node;
}
/* This hook routine is called when a MODIFY_EXPR is being built. We
check what is being modified; if it is a PROPERTY_REF, we need to
generate a 'setter' function call for the property. If this is not
a PROPERTY_REF, we return NULL_TREE and the C/C++ frontend will go
on creating their MODIFY_EXPR.
This is used for example if you write
object.count = 1;
where 'count' is a property. The left-hand side creates a
PROPERTY_REF, and then the compiler tries to generate a MODIFY_EXPR
to assign something to it. We intercept that here, and generate a
call to the 'setter' method instead. */
tree
objc_maybe_build_modify_expr (tree lhs, tree rhs)
{
if (lhs && TREE_CODE (lhs) == PROPERTY_REF)
{
/* Building a simple call to the setter method would work for cases such as
object.count = 1;
but wouldn't work for cases such as
count = object2.count = 1;
to get these to work with very little effort, we build a
compound statement which does the setter call (to set the
property to 'rhs'), but which can also be evaluated returning
the 'rhs'. If the 'rhs' has no side effects, we can simply
evaluate it twice, building
([object setProperty: rhs]; rhs)
If it has side effects, we put it in a temporary variable first,
so we create the following:
(temp = rhs; [object setProperty: temp]; temp)
setter_argument is rhs in the first case, and temp in the second
case.
*/
tree setter_argument;
/* s1, s2 and s3 are the tree statements that we need in the
compound expression. */
tree s1, s2, s3, compound_expr;
if (TREE_SIDE_EFFECTS (rhs))
{
tree bind;
/* Declare __objc_property_temp in a local bind. */
setter_argument = objc_create_temporary_var (TREE_TYPE (rhs), "__objc_property_temp");
DECL_SOURCE_LOCATION (setter_argument) = input_location;
bind = build3 (BIND_EXPR, void_type_node, setter_argument, NULL, NULL);
SET_EXPR_LOCATION (bind, input_location);
TREE_SIDE_EFFECTS (bind) = 1;
add_stmt (bind);
/* s1: x = rhs */
s1 = build_modify_expr (input_location, setter_argument, NULL_TREE,
NOP_EXPR,
input_location, rhs, NULL_TREE);
SET_EXPR_LOCATION (s1, input_location);
}
else
{
/* No s1. */
setter_argument = rhs;
s1 = NULL_TREE;
}
/* Now build the compound statement. */
/* s2: [object setProperty: x] */
s2 = objc_build_setter_call (lhs, setter_argument);
/* This happens if building the setter failed because the
property is readonly. */
if (s2 == error_mark_node)
return error_mark_node;
SET_EXPR_LOCATION (s2, input_location);
/* s3: x */
s3 = convert (TREE_TYPE (lhs), setter_argument);
/* Now build the compound statement (s1, s2, s3) or (s2, s3) as
appropriate. */
if (s1)
compound_expr = build_compound_expr (input_location, build_compound_expr (input_location, s1, s2), s3);
else
compound_expr = build_compound_expr (input_location, s2, s3);
/* Without this, with -Wall you get a 'valued computed is not
used' every time there is a "object.property = x" where the
value of the resulting MODIFY_EXPR is not used. That is
correct (maybe a more sophisticated implementation could
avoid generating the compound expression if not needed), but
we need to turn it off. */
suppress_warning (compound_expr, OPT_Wunused);
return compound_expr;
}
else
return NULL_TREE;
}
/* This hook is called by the frontend when one of the four unary
expressions PREINCREMENT_EXPR, POSTINCREMENT_EXPR,
PREDECREMENT_EXPR and POSTDECREMENT_EXPR is being built with an
argument which is a PROPERTY_REF. For example, this happens if you have
object.count++;
where 'count' is a property. We need to use the 'getter' and
'setter' for the property in an appropriate way to build the
appropriate expression. 'code' is the code for the expression (one
of the four mentioned above); 'argument' is the PROPERTY_REF, and
'increment' is how much we need to add or subtract. */
tree
objc_build_incr_expr_for_property_ref (location_t location,
enum tree_code code,
tree argument, tree increment)
{
/* Here are the expressions that we want to build:
For PREINCREMENT_EXPR / PREDECREMENT_EXPR:
(temp = [object property] +/- increment, [object setProperty: temp], temp)
For POSTINCREMENT_EXPR / POSTECREMENT_EXPR:
(temp = [object property], [object setProperty: temp +/- increment], temp) */
tree temp_variable_decl, bind;
/* s1, s2 and s3 are the tree statements that we need in the
compound expression. */
tree s1, s2, s3, compound_expr;
/* Safety check. */
if (!argument || TREE_CODE (argument) != PROPERTY_REF)
return error_mark_node;
/* Declare __objc_property_temp in a local bind. */
temp_variable_decl = objc_create_temporary_var (TREE_TYPE (argument), "__objc_property_temp");
DECL_SOURCE_LOCATION (temp_variable_decl) = location;
bind = build3 (BIND_EXPR, void_type_node, temp_variable_decl, NULL, NULL);
SET_EXPR_LOCATION (bind, location);
TREE_SIDE_EFFECTS (bind) = 1;
add_stmt (bind);
/* Now build the compound statement. */
/* Note that the 'getter' is generated at gimplify time; at this
time, we can simply put the property_ref (ie, argument) wherever
we want the getter ultimately to be. */
/* s1: __objc_property_temp = [object property] <+/- increment> */
switch (code)
{
case PREINCREMENT_EXPR:
/* __objc_property_temp = [object property] + increment */
s1 = build_modify_expr (location, temp_variable_decl, NULL_TREE,
NOP_EXPR,
location, build2 (PLUS_EXPR, TREE_TYPE (argument),
argument, increment), NULL_TREE);
break;
case PREDECREMENT_EXPR:
/* __objc_property_temp = [object property] - increment */
s1 = build_modify_expr (location, temp_variable_decl, NULL_TREE,
NOP_EXPR,
location, build2 (MINUS_EXPR, TREE_TYPE (argument),
argument, increment), NULL_TREE);
break;
case POSTINCREMENT_EXPR:
case POSTDECREMENT_EXPR:
/* __objc_property_temp = [object property] */
s1 = build_modify_expr (location, temp_variable_decl, NULL_TREE,
NOP_EXPR,
location, argument, NULL_TREE);
break;
default:
gcc_unreachable ();
}
/* s2: [object setProperty: __objc_property_temp <+/- increment>] */
switch (code)
{
case PREINCREMENT_EXPR:
case PREDECREMENT_EXPR:
/* [object setProperty: __objc_property_temp] */
s2 = objc_build_setter_call (argument, temp_variable_decl);
break;
case POSTINCREMENT_EXPR:
/* [object setProperty: __objc_property_temp + increment] */
s2 = objc_build_setter_call (argument,
build2 (PLUS_EXPR, TREE_TYPE (argument),
temp_variable_decl, increment));
break;
case POSTDECREMENT_EXPR:
/* [object setProperty: __objc_property_temp - increment] */
s2 = objc_build_setter_call (argument,
build2 (MINUS_EXPR, TREE_TYPE (argument),
temp_variable_decl, increment));
break;
default:
gcc_unreachable ();
}
/* This happens if building the setter failed because the property
is readonly. */
if (s2 == error_mark_node)
return error_mark_node;
SET_EXPR_LOCATION (s2, location);
/* s3: __objc_property_temp */
s3 = convert (TREE_TYPE (argument), temp_variable_decl);
/* Now build the compound statement (s1, s2, s3) */
compound_expr = build_compound_expr (location, build_compound_expr (location, s1, s2), s3);
/* Prevent C++ from warning with -Wall that "right operand of comma
operator has no effect". */
suppress_warning (compound_expr, OPT_Wunused);
return compound_expr;
}
tree
objc_build_method_signature (bool is_class_method, tree rettype, tree selector,
tree optparms, bool ellipsis)
{
if (is_class_method)
return build_method_decl (CLASS_METHOD_DECL, rettype, selector,
optparms, ellipsis);
else
return build_method_decl (INSTANCE_METHOD_DECL, rettype, selector,
optparms, ellipsis);
}
void
objc_add_method_declaration (bool is_class_method, tree decl, tree attributes)
{
if (!objc_interface_context)
{
/* PS: At the moment, due to how the parser works, it should be
impossible to get here. But it's good to have the check in
case the parser changes.
*/
fatal_error (input_location,
"method declaration not in @interface context");
}
if (flag_objc1_only && attributes)
error_at (input_location, "method attributes are not available in Objective-C 1.0");
objc_decl_method_attributes (&decl, attributes, 0);
objc_add_method (objc_interface_context,
decl,
is_class_method,
objc_method_optional_flag);
}
/* Return 'true' if the method definition could be started, and
'false' if not (because we are outside an @implementation context).
EXPR is NULL or an expression that needs to be evaluated for the
side effects of array size expressions in the parameters.
*/
bool
objc_start_method_definition (bool is_class_method, tree decl, tree attributes,
tree expr)
{
if (!objc_implementation_context)
{
error ("method definition not in @implementation context");
return false;
}
if (decl != NULL_TREE && METHOD_SEL_NAME (decl) == error_mark_node)
return false;
#ifndef OBJCPLUS
/* Indicate no valid break/continue context. */
in_statement = 0;
#endif
if (attributes)
warning_at (input_location, 0, "method attributes cannot be specified in @implementation context");
else
objc_decl_method_attributes (&decl, attributes, 0);
objc_add_method (objc_implementation_context,
decl,
is_class_method,
/* is optional */ false);
start_method_def (decl, expr);
return true;
}
void
objc_add_instance_variable (tree decl)
{
(void) add_instance_variable (objc_ivar_context,
objc_ivar_visibility,
decl);
}
/* Construct a C struct with same name as KLASS, a base struct with tag
SUPER_NAME (if any), and FIELDS indicated. */
static tree
objc_build_struct (tree klass, tree fields, tree super_name)
{
tree name = CLASS_NAME (klass);
tree s = objc_start_struct (name);
tree super = (super_name ? xref_tag (RECORD_TYPE, super_name) : NULL_TREE);
tree t;
vec<tree> objc_info = vNULL;
int i;
if (super)
{
/* Prepend a packed variant of the base class into the layout. This
is necessary to preserve ObjC ABI compatibility. */
tree base = build_decl (input_location,
FIELD_DECL, NULL_TREE, super);
tree field = TYPE_FIELDS (super);
while (field && DECL_CHAIN (field)
&& TREE_CODE (DECL_CHAIN (field)) == FIELD_DECL)
field = DECL_CHAIN (field);
/* For ObjC ABI purposes, the "packed" size of a base class is
the sum of the offset and the size (in bits) of the last field
in the class. */
DECL_SIZE (base)
= (field && TREE_CODE (field) == FIELD_DECL
? size_binop (PLUS_EXPR,
size_binop (PLUS_EXPR,
size_binop
(MULT_EXPR,
convert (bitsizetype,
DECL_FIELD_OFFSET (field)),
bitsize_int (BITS_PER_UNIT)),
DECL_FIELD_BIT_OFFSET (field)),
DECL_SIZE (field))
: bitsize_zero_node);
DECL_SIZE_UNIT (base)
= size_binop (FLOOR_DIV_EXPR, convert (sizetype, DECL_SIZE (base)),
size_int (BITS_PER_UNIT));
DECL_ARTIFICIAL (base) = 1;
SET_DECL_ALIGN (base, 1);
DECL_FIELD_CONTEXT (base) = s;
#ifdef OBJCPLUS
DECL_FIELD_IS_BASE (base) = 1;
if (fields)
/* Suppress C++ ABI warnings: we are following the ObjC ABI here. */
suppress_warning (fields, OPT_Wabi);
#endif
DECL_CHAIN (base) = fields;
fields = base;
}
/* NB: Calling finish_struct() may cause type TYPE_OBJC_INFO
information in all variants of this RECORD_TYPE to be destroyed
(this is because the C frontend manipulates TYPE_LANG_SPECIFIC
for something else and then will change all variants to use the
same resulting TYPE_LANG_SPECIFIC, ignoring the fact that we use
it for ObjC protocols and that such propagation will make all
variants use the same objc_info), but it is therein that we store
protocol conformance info (e.g., 'NSObject <MyProtocol>').
Hence, we must save the ObjC-specific information before calling
finish_struct(), and then reinstate it afterwards. */
for (t = TYPE_MAIN_VARIANT (s); t; t = TYPE_NEXT_VARIANT (t))
{
INIT_TYPE_OBJC_INFO (t);
objc_info.safe_push (TYPE_OBJC_INFO (t));
}
s = objc_finish_struct (s, fields);
for (i = 0, t = TYPE_MAIN_VARIANT (s); t; t = TYPE_NEXT_VARIANT (t), i++)
{
/* We now want to restore the different TYPE_OBJC_INFO, but we
have the additional problem that the C frontend doesn't just
copy TYPE_LANG_SPECIFIC from one variant to the other; it
actually makes all of them the *same* TYPE_LANG_SPECIFIC. As
we need a different TYPE_OBJC_INFO for each (and
TYPE_OBJC_INFO is a field in TYPE_LANG_SPECIFIC), we need to
make a copy of each TYPE_LANG_SPECIFIC before we modify
TYPE_OBJC_INFO. */
if (TYPE_LANG_SPECIFIC (t))
{
/* Create a copy of TYPE_LANG_SPECIFIC. */
struct lang_type *old_lang_type = TYPE_LANG_SPECIFIC (t);
ALLOC_OBJC_TYPE_LANG_SPECIFIC (t);
memcpy (TYPE_LANG_SPECIFIC (t), old_lang_type,
SIZEOF_OBJC_TYPE_LANG_SPECIFIC);
}
else
{
/* Just create a new one. */
ALLOC_OBJC_TYPE_LANG_SPECIFIC (t);
}
/* Replace TYPE_OBJC_INFO with the saved one. This restores any
protocol information that may have been associated with the
type. */
TYPE_OBJC_INFO (t) = objc_info[i];
/* Replace the IDENTIFIER_NODE with an actual @interface now
that we have it. */
TYPE_OBJC_INTERFACE (t) = klass;
}
objc_info.release ();
/* Use TYPE_BINFO structures to point at the super class, if any. */
objc_xref_basetypes (s, super);
/* Mark this struct as a class template. */
CLASS_STATIC_TEMPLATE (klass) = s;
return s;
}
/* Mark DECL as being 'volatile' for purposes of Darwin
_setjmp()/_longjmp() exception handling. Called from
objc_mark_locals_volatile(). */
void
objc_volatilize_decl (tree decl)
{
/* Do not mess with variables that are 'static' or (already)
'volatile'. */
if (!TREE_THIS_VOLATILE (decl) && !TREE_STATIC (decl)
&& (TREE_CODE (decl) == VAR_DECL
|| TREE_CODE (decl) == PARM_DECL))
{
if (local_variables_to_volatilize == NULL)
vec_alloc (local_variables_to_volatilize, 8);
vec_safe_push (local_variables_to_volatilize, decl);
}
}
/* Called when parsing of a function completes; if any local variables
in the function were marked as variables to volatilize, change them
to volatile. We do this at the end of the function when the
warnings about discarding 'volatile' have already been produced.
We are making the variables as volatile just to force the compiler
to preserve them between setjmp/longjmp, but we don't want warnings
for them as they aren't really volatile. */
void
objc_finish_function (void)
{
/* If there are any local variables to volatilize, volatilize them. */
if (local_variables_to_volatilize)
{
int i;
tree decl;
FOR_EACH_VEC_ELT (*local_variables_to_volatilize, i, decl)
{
tree t = TREE_TYPE (decl);
t = build_qualified_type (t, TYPE_QUALS (t) | TYPE_QUAL_VOLATILE);
TREE_TYPE (decl) = t;
TREE_THIS_VOLATILE (decl) = 1;
TREE_SIDE_EFFECTS (decl) = 1;
DECL_REGISTER (decl) = 0;
#ifndef OBJCPLUS
C_DECL_REGISTER (decl) = 0;
#endif
}
/* Now we delete the vector. This sets it to NULL as well. */
vec_free (local_variables_to_volatilize);
}
}
/* Check if protocol PROTO is adopted (directly or indirectly) by class CLS
(including its categories and superclasses) or by object type TYP.
Issue a warning if PROTO is not adopted anywhere and WARN is set. */
static bool
objc_lookup_protocol (tree proto, tree cls, tree typ, bool warn)
{
bool class_type = (cls != NULL_TREE);
while (cls)
{
tree c;
/* Check protocols adopted by the class and its categories. */
for (c = cls; c; c = CLASS_CATEGORY_LIST (c))
{
if (lookup_protocol_in_reflist (CLASS_PROTOCOL_LIST (c), proto))
return true;
}
/* Repeat for superclasses. */
cls = lookup_interface (CLASS_SUPER_NAME (cls));
}
/* Check for any protocols attached directly to the object type. */
if (TYPE_HAS_OBJC_INFO (typ))
{
if (lookup_protocol_in_reflist (TYPE_OBJC_PROTOCOL_LIST (typ), proto))
return true;
}
if (warn)
{
*errbuf = 0;
gen_type_name_0 (class_type ? typ : TYPE_POINTER_TO (typ));
/* NB: Types 'id' and 'Class' cannot reasonably be described as
"implementing" a given protocol, since they do not have an
implementation. */
if (class_type)
warning (0, "class %qs does not implement the %qE protocol",
identifier_to_locale (errbuf), PROTOCOL_NAME (proto));
else
warning (0, "type %qs does not conform to the %qE protocol",
identifier_to_locale (errbuf), PROTOCOL_NAME (proto));
}
return false;
}
/* Check if class RCLS and instance struct type RTYP conform to at least the
same protocols that LCLS and LTYP conform to. */
static bool
objc_compare_protocols (tree lcls, tree ltyp, tree rcls, tree rtyp, bool warn)
{
tree p;
bool have_lproto = false;
while (lcls)
{
/* NB: We do _not_ look at categories defined for LCLS; these may or
may not get loaded in, and therefore it is unreasonable to require
that RCLS/RTYP must implement any of their protocols. */
for (p = CLASS_PROTOCOL_LIST (lcls); p; p = TREE_CHAIN (p))
{
have_lproto = true;
if (!objc_lookup_protocol (TREE_VALUE (p), rcls, rtyp, warn))
return warn;
}
/* Repeat for superclasses. */
lcls = lookup_interface (CLASS_SUPER_NAME (lcls));
}
/* Check for any protocols attached directly to the object type. */
if (TYPE_HAS_OBJC_INFO (ltyp))
{
for (p = TYPE_OBJC_PROTOCOL_LIST (ltyp); p; p = TREE_CHAIN (p))
{
have_lproto = true;
if (!objc_lookup_protocol (TREE_VALUE (p), rcls, rtyp, warn))
return warn;
}
}
/* NB: If LTYP and LCLS have no protocols to search for, return 'true'
vacuously, _unless_ RTYP is a protocol-qualified 'id'. We can get
away with simply checking for 'id' or 'Class' (!RCLS), since this
routine will not get called in other cases. */
return have_lproto || (rcls != NULL_TREE);
}
/* Given two types TYPE1 and TYPE2, return their least common ancestor.
Both TYPE1 and TYPE2 must be pointers, and already determined to be
compatible by objc_compare_types() below. */
tree
objc_common_type (tree type1, tree type2)
{
tree inner1 = TREE_TYPE (type1), inner2 = TREE_TYPE (type2);
while (POINTER_TYPE_P (inner1))
{
inner1 = TREE_TYPE (inner1);
inner2 = TREE_TYPE (inner2);
}
/* If one type is derived from another, return the base type. */
if (DERIVED_FROM_P (inner1, inner2))
return type1;
else if (DERIVED_FROM_P (inner2, inner1))
return type2;
/* If both types are 'Class', return 'Class'. */
if (objc_is_class_id (inner1) && objc_is_class_id (inner2))
return objc_class_type;
/* Otherwise, return 'id'. */
return objc_object_type;
}
/* Determine if it is permissible to assign (if ARGNO is greater than -3)
an instance of RTYP to an instance of LTYP or to compare the two
(if ARGNO is equal to -3), per ObjC type system rules. Before
returning 'true', this routine may issue warnings related to, e.g.,
protocol conformance. When returning 'false', the routine must
produce absolutely no warnings; the C or C++ front-end will do so
instead, if needed. If either LTYP or RTYP is not an Objective-C
type, the routine must return 'false'.
The ARGNO parameter is encoded as follows:
>= 1 Parameter number (CALLEE contains function being called);
0 Return value;
-1 Assignment;
-2 Initialization;
-3 Comparison (LTYP and RTYP may match in either direction);
-4 Silent comparison (for C++ overload resolution);
-5 Silent "specialization" comparison for RTYP to be a "specialization"
of LTYP (a specialization means that RTYP is LTYP plus some constraints,
so that each object of type RTYP is also of type LTYP). This is used
when comparing property types. */
bool
objc_compare_types (tree ltyp, tree rtyp, int argno, tree callee)
{
tree lcls, rcls, lproto, rproto;
bool pointers_compatible;
/* We must be dealing with pointer types */
if (!POINTER_TYPE_P (ltyp) || !POINTER_TYPE_P (rtyp))
return false;
tree ltyp_attr, rtyp_attr;
do
{
/* Remove indirections, but keep the type attributes from the innermost
pointer type, to check for NSObject. */
ltyp_attr = TYPE_ATTRIBUTES (ltyp);
ltyp = TREE_TYPE (ltyp);
rtyp_attr = TYPE_ATTRIBUTES (rtyp);
rtyp = TREE_TYPE (rtyp);
}
while (POINTER_TYPE_P (ltyp) && POINTER_TYPE_P (rtyp));
/* We must also handle function pointers, since ObjC is a bit more
lenient than C or C++ on this. */
if (TREE_CODE (ltyp) == FUNCTION_TYPE && TREE_CODE (rtyp) == FUNCTION_TYPE)
{
function_args_iterator liter, riter;
/* Return types must be covariant. */
if (!comptypes (TREE_TYPE (ltyp), TREE_TYPE (rtyp))
&& !objc_compare_types (TREE_TYPE (ltyp), TREE_TYPE (rtyp),
argno, callee))
return false;
/* Argument types must be contravariant. */
function_args_iter_init (&liter, ltyp);
function_args_iter_init (&riter, rtyp);
while (1)
{
ltyp = function_args_iter_cond (&liter);
rtyp = function_args_iter_cond (&riter);
/* If we've exhaused both lists simulateously, we're done. */
if (ltyp == NULL_TREE && rtyp == NULL_TREE)
break;
/* If one list is shorter than the other, they fail to match. */
if (ltyp == NULL_TREE || rtyp == NULL_TREE)
return false;
if (!comptypes (rtyp, ltyp)
&& !objc_compare_types (rtyp, ltyp, argno, callee))
return false;
function_args_iter_next (&liter);
function_args_iter_next (&riter);
}
return true;
}
/* We might have void * with NSObject type attr. */
bool l_NSObject_p = ltyp_attr && lookup_attribute ("NSObject", ltyp_attr);
bool r_NSObject_p = rtyp_attr && lookup_attribute ("NSObject", rtyp_attr);
/* Past this point, we are only interested in ObjC class instances,
or 'id' or 'Class' (except if the user applied the NSObject type
attribute). */
if ((TREE_CODE (ltyp) != RECORD_TYPE && !l_NSObject_p)
|| (TREE_CODE (rtyp) != RECORD_TYPE && !r_NSObject_p))
return false;
if (!objc_is_object_id (ltyp) && !objc_is_class_id (ltyp)
&& !TYPE_HAS_OBJC_INFO (ltyp) && !l_NSObject_p)
return false;
if (!objc_is_object_id (rtyp) && !objc_is_class_id (rtyp)
&& !TYPE_HAS_OBJC_INFO (rtyp) && !r_NSObject_p)
return false;
/* Past this point, we are committed to returning 'true' to the caller
(unless performing a silent comparison; see below). However, we can
still warn about type and/or protocol mismatches. */
if (TYPE_HAS_OBJC_INFO (ltyp))
{
lcls = TYPE_OBJC_INTERFACE (ltyp);
lproto = TYPE_OBJC_PROTOCOL_LIST (ltyp);
}
else
lcls = lproto = NULL_TREE;
if (TYPE_HAS_OBJC_INFO (rtyp))
{
rcls = TYPE_OBJC_INTERFACE (rtyp);
rproto = TYPE_OBJC_PROTOCOL_LIST (rtyp);
}
else
rcls = rproto = NULL_TREE;
/* If we could not find an @interface declaration, we must have
only seen a @class declaration; for purposes of type comparison,
treat it as a stand-alone (root) class. */
if (lcls && TREE_CODE (lcls) == IDENTIFIER_NODE)
lcls = NULL_TREE;
if (rcls && TREE_CODE (rcls) == IDENTIFIER_NODE)
rcls = NULL_TREE;
/* If either type is an unqualified 'id', we're done. This is because
an 'id' can be assigned to or from any type with no warnings. When
the pointer has NSObject attribute, consider that to be equivalent. */
if (argno != -5)
{
if ((!lproto && objc_is_object_id (ltyp))
|| (!rproto && objc_is_object_id (rtyp)))
return true;
if (l_NSObject_p || r_NSObject_p)
return true;
}
else
{
/* For property checks, though, an 'id' is considered the most
general type of object, hence if you try to specialize an
'NSArray *' (ltyp) property with an 'id' (rtyp) one, we need
to warn. */
if (!lproto && (objc_is_object_id (ltyp) || l_NSObject_p))
return true;
}
pointers_compatible = (TYPE_MAIN_VARIANT (ltyp) == TYPE_MAIN_VARIANT (rtyp));
/* If the underlying types are the same, and at most one of them has
a protocol list, we do not need to issue any diagnostics. */
if (pointers_compatible && (!lproto || !rproto))
return true;
/* If exactly one of the types is 'Class', issue a diagnostic; any
exceptions of this rule have already been handled. */
if (objc_is_class_id (ltyp) ^ objc_is_class_id (rtyp))
pointers_compatible = false;
/* Otherwise, check for inheritance relations. */
else
{
if (!pointers_compatible)
{
/* Again, if any of the two is an 'id', we're satisfied,
unless we're comparing properties, in which case only an
'id' on the left-hand side (old property) is good
enough. */
if (argno != -5)
pointers_compatible
= (objc_is_object_id (ltyp) || objc_is_object_id (rtyp));
else
pointers_compatible = objc_is_object_id (ltyp);
}
if (!pointers_compatible)
pointers_compatible = DERIVED_FROM_P (ltyp, rtyp);
if (!pointers_compatible && (argno == -3 || argno == -4))
pointers_compatible = DERIVED_FROM_P (rtyp, ltyp);
}
/* If the pointers match modulo protocols, check for protocol conformance
mismatches. */
if (pointers_compatible)
{
pointers_compatible = objc_compare_protocols (lcls, ltyp, rcls, rtyp,
argno != -3);
if (!pointers_compatible && argno == -3)
pointers_compatible = objc_compare_protocols (rcls, rtyp, lcls, ltyp,
argno != -3);
}
if (!pointers_compatible)
{
/* The two pointers are not exactly compatible. Issue a warning, unless
we are performing a silent comparison, in which case return 'false'
instead. */
/* NB: For the time being, we shall make our warnings look like their
C counterparts. In the future, we may wish to make them more
ObjC-specific. */
switch (argno)
{
case -5:
case -4:
return false;
case -3:
warning (0, "comparison of distinct Objective-C types lacks a cast");
break;
case -2:
warning (0, "initialization from distinct Objective-C type");
break;
case -1:
warning (0, "assignment from distinct Objective-C type");
break;
case 0:
warning (0, "distinct Objective-C type in return");
break;
default:
warning (0, "passing argument %d of %qE from distinct "
"Objective-C type", argno, callee);
break;
}
}
return true;
}
/* This routine is similar to objc_compare_types except that function-pointers are
excluded. This is because, caller assumes that common types are of (id, Object*)
variety and calls objc_common_type to obtain a common type. There is no commonolty
between two function-pointers in this regard. */
bool
objc_have_common_type (tree ltyp, tree rtyp, int argno, tree callee)
{
if (objc_compare_types (ltyp, rtyp, argno, callee))
{
/* exclude function-pointer types. */
do
{
ltyp = TREE_TYPE (ltyp); /* Remove indirections. */
rtyp = TREE_TYPE (rtyp);
}
while (POINTER_TYPE_P (ltyp) && POINTER_TYPE_P (rtyp));
return !(TREE_CODE (ltyp) == FUNCTION_TYPE && TREE_CODE (rtyp) == FUNCTION_TYPE);
}
return false;
}
#ifndef OBJCPLUS
/* Determine if CHILD is derived from PARENT. The routine assumes that
both parameters are RECORD_TYPEs, and is non-reflexive. */
static bool
objc_derived_from_p (tree parent, tree child)
{
parent = TYPE_MAIN_VARIANT (parent);
for (child = TYPE_MAIN_VARIANT (child);
TYPE_BINFO (child) && BINFO_N_BASE_BINFOS (TYPE_BINFO (child));)
{
child = TYPE_MAIN_VARIANT (BINFO_TYPE (BINFO_BASE_BINFO
(TYPE_BINFO (child),
0)));
if (child == parent)
return true;
}
return false;
}
#endif
tree
objc_build_component_ref (tree datum, tree component)
{
/* If COMPONENT is NULL, the caller is referring to the anonymous
base class field. */
if (!component)
{
tree base = TYPE_FIELDS (TREE_TYPE (datum));
return build3 (COMPONENT_REF, TREE_TYPE (base), datum, base, NULL_TREE);
}
/* The 'build_component_ref' routine has been removed from the C++
front-end, but 'finish_class_member_access_expr' seems to be
a worthy substitute. */
#ifdef OBJCPLUS
return finish_class_member_access_expr (datum, component, false,
tf_warning_or_error);
#else
return build_component_ref (input_location, datum, component,
UNKNOWN_LOCATION);
#endif
}
/* Recursively copy inheritance information rooted at BINFO. To do this,
we emulate the song and dance performed by cp/tree.c:copy_binfo(). */
static tree
objc_copy_binfo (tree binfo)
{
tree btype = BINFO_TYPE (binfo);
tree binfo2 = make_tree_binfo (BINFO_N_BASE_BINFOS (binfo));
tree base_binfo;
int ix;
BINFO_TYPE (binfo2) = btype;
BINFO_OFFSET (binfo2) = BINFO_OFFSET (binfo);
BINFO_BASE_ACCESSES (binfo2) = BINFO_BASE_ACCESSES (binfo);
/* Recursively copy base binfos of BINFO. */
for (ix = 0; BINFO_BASE_ITERATE (binfo, ix, base_binfo); ix++)
{
tree base_binfo2 = objc_copy_binfo (base_binfo);
BINFO_INHERITANCE_CHAIN (base_binfo2) = binfo2;
BINFO_BASE_APPEND (binfo2, base_binfo2);
}
return binfo2;
}
/* Record superclass information provided in BASETYPE for ObjC class REF.
This is loosely based on cp/decl.c:xref_basetypes(). */
static void
objc_xref_basetypes (tree ref, tree basetype)
{
tree variant;
tree binfo = make_tree_binfo (basetype ? 1 : 0);
TYPE_BINFO (ref) = binfo;
BINFO_OFFSET (binfo) = size_zero_node;
BINFO_TYPE (binfo) = ref;
gcc_assert (TYPE_MAIN_VARIANT (ref) == ref);
for (variant = ref; variant; variant = TYPE_NEXT_VARIANT (variant))
TYPE_BINFO (variant) = binfo;
if (basetype)
{
tree base_binfo = objc_copy_binfo (TYPE_BINFO (basetype));
BINFO_INHERITANCE_CHAIN (base_binfo) = binfo;
vec_alloc (BINFO_BASE_ACCESSES (binfo), 1);
BINFO_BASE_APPEND (binfo, base_binfo);
BINFO_BASE_ACCESS_APPEND (binfo, access_public_node);
}
}
/* Called from finish_decl. */
void
objc_check_decl (tree decl)
{
tree type = TREE_TYPE (decl);
if (TREE_CODE (type) != RECORD_TYPE)
return;
if (OBJC_TYPE_NAME (type) && (type = objc_is_class_name (OBJC_TYPE_NAME (type))))
error ("statically allocated instance of Objective-C class %qE",
type);
}
void
objc_check_global_decl (tree decl)
{
tree id = DECL_NAME (decl);
if (objc_is_class_name (id) && global_bindings_p())
error ("redeclaration of Objective-C class %qs", IDENTIFIER_POINTER (id));
}
/* Construct a PROTOCOLS-qualified variant of INTERFACE, where
INTERFACE may either name an Objective-C class, or refer to the
special 'id' or 'Class' types. If INTERFACE is not a valid ObjC
type, just return it unchanged. This function is often called when
PROTOCOLS is NULL_TREE, in which case we simply look up the
appropriate INTERFACE. */
tree
objc_get_protocol_qualified_type (tree interface, tree protocols)
{
/* If INTERFACE is not provided, default to 'id'. */
tree type = (interface ? objc_is_id (interface) : objc_object_type);
bool is_ptr = (type != NULL_TREE);
if (!is_ptr)
{
type = objc_is_class_name (interface);
if (type)
{
/* If looking at a typedef, retrieve the precise type it
describes. */
if (TREE_CODE (interface) == IDENTIFIER_NODE)
interface = identifier_global_value (interface);
type = ((interface && TREE_CODE (interface) == TYPE_DECL
&& DECL_ORIGINAL_TYPE (interface))
? DECL_ORIGINAL_TYPE (interface)
: xref_tag (RECORD_TYPE, type));
}
else
{
/* This case happens when we are given an 'interface' which
is not a valid class name. For example if a typedef was
used, and 'interface' really is the identifier of the
typedef, but when you resolve it you don't get an
Objective-C class, but something else, such as 'int'.
This is an error; protocols make no sense unless you use
them with Objective-C objects. */
error_at (input_location, "only Objective-C object types can be qualified with a protocol");
/* Try to recover. Ignore the invalid class name, and treat
the object as an 'id' to silence further warnings about
the class. */
type = objc_object_type;
is_ptr = true;
}
}
if (protocols)
{
type = build_variant_type_copy (type);
/* For pointers (i.e., 'id' or 'Class'), attach the protocol(s)
to the pointee. */
if (is_ptr)
{
tree orig_pointee_type = TREE_TYPE (type);
TREE_TYPE (type) = build_variant_type_copy (orig_pointee_type);
/* Set up the canonical type information. */
TYPE_CANONICAL (type)
= TYPE_CANONICAL (TYPE_POINTER_TO (orig_pointee_type));
TYPE_POINTER_TO (TREE_TYPE (type)) = type;
type = TREE_TYPE (type);
}
/* Look up protocols and install in lang specific list. */
DUP_TYPE_OBJC_INFO (type, TYPE_MAIN_VARIANT (type));
TYPE_OBJC_PROTOCOL_LIST (type) = lookup_and_install_protocols
(protocols, /* definition_required */ false);
/* For RECORD_TYPEs, point to the @interface; for 'id' and 'Class',
return the pointer to the new pointee variant. */
if (is_pt