Files
mercury/compiler/mlds_to_c_class.m
2018-06-30 19:03:53 +02:00

404 lines
16 KiB
Mathematica

%---------------------------------------------------------------------------%
% vim: ft=mercury ts=4 sw=4 et
%---------------------------------------------------------------------------%
% Copyright (C) 2018 The Mercury team.
% This file may only be copied under the terms of the GNU General
% Public License - see the file COPYING in the Mercury distribution.
%---------------------------------------------------------------------------%
%
% Output the declarations and definitions of classes.
%
%---------------------------------------------------------------------------%
:- module ml_backend.mlds_to_c_class.
:- interface.
:- import_module ml_backend.mlds.
:- import_module ml_backend.mlds_to_c_util.
:- import_module ml_backend.mlds_to_target_util.
:- import_module io.
%---------------------------------------------------------------------------%
:- pred mlds_output_class_defn(mlds_to_c_opts::in, indent::in,
mlds_module_name::in, mlds_class_defn::in, io::di, io::uo) is det.
%---------------------------------------------------------------------------%
%---------------------------------------------------------------------------%
:- implementation.
:- import_module hlds.
:- import_module hlds.hlds_pred. % for pred_proc_id.
:- import_module libs.
:- import_module libs.globals.
:- import_module ml_backend.ml_code_util.
:- import_module ml_backend.mlds_to_c_data.
:- import_module ml_backend.mlds_to_c_func.
:- import_module ml_backend.mlds_to_c_name.
:- import_module ml_backend.mlds_to_c_stmt.
:- import_module ml_backend.mlds_to_c_type.
:- import_module parse_tree.
:- import_module parse_tree.prog_data.
:- import_module bool.
:- import_module char.
:- import_module int.
:- import_module list.
:- import_module maybe.
:- import_module require.
:- import_module term.
%---------------------------------------------------------------------------%
:- pred mlds_output_class_decl_opts(mlds_to_c_opts::in, indent::in,
mlds_module_name::in, mlds_class_defn::in, io::di, io::uo) is det.
:- pragma consider_used(mlds_output_class_decl_opts/6).
mlds_output_class_decl_opts(Opts, Indent, ModuleName, ClassDefn, !IO) :-
ClassDefn = mlds_class_defn(ClassName, Arity, Context, Flags, Kind,
_Imports, _Inherits, _Implements,
_TypeParams, _MemberFields, _MemberClasses, _MemberMethods, _Ctors),
% ANSI C does not permit forward declarations of enumeration types.
% So we just skip those. Currently they are not needed since we do not
% actually use the enum types.
( if Kind = mlds_enum then
true
else
c_output_context(Opts ^ m2co_line_numbers, Context, !IO),
output_n_indents(Indent, !IO),
mlds_output_class_decl_flags(Opts, Flags, forward_decl, !IO),
mlds_output_class_decl(Indent, ModuleName, ClassName, Arity, ClassDefn,
!IO),
io.write_string(";\n", !IO)
).
:- pred mlds_output_class_decl(indent::in, mlds_module_name::in,
mlds_class_name::in, arity::in, mlds_class_defn::in,
io::di, io::uo) is det.
mlds_output_class_decl(_Indent, ModuleName, ClassName, Arity,
ClassDefn, !IO) :-
ClassKind = ClassDefn ^ mcd_kind,
(
ClassKind = mlds_enum,
io.write_string("enum ", !IO),
output_qual_name_prefix_c(ModuleName, !IO),
mlds_output_class_name_arity(ClassName, Arity, !IO),
io.write_string("_e", !IO)
;
( ClassKind = mlds_class
; ClassKind = mlds_interface
; ClassKind = mlds_struct
),
io.write_string("struct ", !IO),
output_qual_name_prefix_c(ModuleName, !IO),
mlds_output_class_name_arity(ClassName, Arity, !IO),
io.write_string("_s", !IO)
).
%---------------------------------------------------------------------------%
:- pred mlds_output_class_defns(mlds_to_c_opts::in, indent::in,
mlds_module_name::in, list(mlds_class_defn)::in,
io::di, io::uo) is det.
mlds_output_class_defns(_Opts, _Indent, _ModuleName, [], !IO).
mlds_output_class_defns(Opts, Indent, ModuleName,
[ClassDefn | ClassDefns], !IO) :-
mlds_output_class_defn(Opts, Indent, ModuleName, ClassDefn, !IO),
mlds_output_class_defns(Opts, Indent, ModuleName, ClassDefns, !IO).
mlds_output_class_defn(Opts, Indent, ModuleName, ClassDefn, !IO) :-
ClassDefn = mlds_class_defn(_ClassName, _Arity, Context, Flags, _Kind,
_Imports, _Inherits, _Implements, _TypeParams,
_MemberFields, _MemberClasses, _MemberMethods, _Ctors),
io.nl(!IO),
c_output_context(Opts ^ m2co_line_numbers, Context, !IO),
output_n_indents(Indent, !IO),
mlds_output_class_decl_flags(Opts, Flags, definition, !IO),
mlds_output_class(Opts, Indent, ModuleName, ClassDefn, !IO).
%---------------------------------------------------------------------------%
:- pred mlds_output_class(mlds_to_c_opts::in, indent::in,
mlds_module_name::in, mlds_class_defn::in,
io::di, io::uo) is det.
mlds_output_class(Opts, Indent, ModuleName, ClassDefn, !IO) :-
ClassDefn = mlds_class_defn(ClassName, ClassArity, Context, _Flags,
Kind, _Imports, Inherits, _Implements, _TypeParams,
MemberFields, MemberClasses, MemberMethods, Ctors),
expect(unify(MemberMethods, []), $pred,
"MemberMethods != []"),
% To avoid name clashes, we need to qualify the names of the member
% constants with the class name. (In particular, this is needed for
% enumeration constants and for the nested classes that we generate for
% constructors of discriminated union types.) Here we compute the
% appropriate qualifier.
ClassModuleName = mlds_append_class_qualifier_module_qual(ModuleName,
ClassName, ClassArity),
% Hoist out static members, since plain old C does not support
% static members in structs (except for enumeration constants).
%
% XXX This should be conditional: only when compiling to C,
% not when compiling to C++.
(
Kind = mlds_enum,
StaticCtors = [],
StructCtors = Ctors,
StaticMemberFields = [],
StructMemberFields = MemberFields
;
( Kind = mlds_class
; Kind = mlds_interface
; Kind = mlds_struct
),
list.filter(function_defn_is_static_member, Ctors,
StaticCtors, NonStaticCtors),
list.filter(field_var_defn_is_static_member, MemberFields,
StaticMemberFields, NonStaticMemberFields),
StructCtors = NonStaticCtors,
StructMemberFields = NonStaticMemberFields
),
% Convert the base classes into member variables,
% since plain old C does not support base classes.
%
% XXX this should be conditional: only when compiling to C,
% not when compiling to C++
(
Inherits = inherits_nothing,
BaseFieldVarDefns = []
;
Inherits = inherits_class(BaseClassId),
BaseVarName = fvn_base_class(1),
Type = mlds_class_type(BaseClassId),
% We only need GC tracing code for top-level variables,
% not for base classes.
GCStmt = gc_no_stmt,
BaseFieldVarDefns = [mlds_field_var_defn(BaseVarName, Context,
ml_gen_public_field_decl_flags, Type, no_initializer, GCStmt)]
;
Inherits = inherits_generic_env_ptr_type,
% This should happen only if the target language requires
% put_nondet_env_on_heap to be "yes"; for C, it should be "no".
unexpected($pred, "inherits_generic_env_ptr_type")
),
% Output the class declaration and the class members.
% We treat enumerations specially.
%
% Note that standard ANSI/ISO C does not allow empty structs. We could
% handle empty structs here, by adding a dummy member, but that would
% waste a lot of space, and would also cause incompatibilities between
% the data layout for --high-level-data and --no-high-level-data.
% So instead, we make it is the responsibility of the MLDS code generator
% to not generate any. (E.g. ml_type_gen.m checks whether
% `target_uses_empty_base_classes' before generating empty structs.)
% Hence we do not need to check for empty structs here.
mlds_output_class_decl(Indent, ModuleName, ClassName, ClassArity,
ClassDefn, !IO),
io.write_string(" {\n", !IO),
(
Kind = mlds_enum,
mlds_output_enum_constants(Opts, Indent + 1, ClassModuleName,
BaseFieldVarDefns, !IO),
mlds_output_enum_constants(Opts, Indent + 1, ClassModuleName,
StructMemberFields, !IO)
;
( Kind = mlds_class
; Kind = mlds_interface
; Kind = mlds_struct
),
% XXX Why don't we output all the field vars in one block?
list.foldl(
mlds_output_field_var_defn(Opts, Indent + 1, no, ClassModuleName),
BaseFieldVarDefns, !IO),
list.foldl(
mlds_output_function_defn(Opts, Indent + 1, ClassModuleName),
StructCtors, !IO),
list.foldl(
mlds_output_field_var_defn(Opts, Indent + 1, no, ClassModuleName),
StructMemberFields, !IO)
),
c_output_context(Opts ^ m2co_line_numbers, Context, !IO),
output_n_indents(Indent, !IO),
io.write_string("};\n", !IO),
mlds_output_function_defns(Opts, Indent, ClassModuleName,
StaticCtors, !IO),
mlds_output_field_var_defns(Opts, Indent, yes, ClassModuleName,
StaticMemberFields, !IO),
mlds_output_class_defns(Opts, Indent, ClassModuleName,
MemberClasses, !IO).
%---------------------------------------------------------------------------%
:- pred function_defn_is_static_member(mlds_function_defn::in) is semidet.
function_defn_is_static_member(FuncDefn) :-
FuncDefn ^ mfd_decl_flags ^ mfdf_per_instance = one_copy.
:- pred field_var_defn_is_static_member(mlds_field_var_defn::in) is semidet.
field_var_defn_is_static_member(FieldVarDefn) :-
FieldVarDefn ^ mfvd_decl_flags ^ mfvdf_per_instance = one_copy.
%---------------------------------------------------------------------------%
:- pred mlds_output_field_var_decl(mlds_to_c_opts::in, qual_field_var_name::in,
mlds_type::in, initializer_array_size::in, io::di, io::uo) is det.
mlds_output_field_var_decl(Opts, FieldVarName, Type, InitializerSize, !IO) :-
mlds_output_type_prefix(Opts, Type, !IO),
io.write_char(' ', !IO),
mlds_output_fully_qualified_field_var_name(FieldVarName, !IO),
mlds_output_type_suffix(Opts, Type, InitializerSize, !IO).
:- pred mlds_output_field_var_defns(mlds_to_c_opts::in, indent::in, bool::in,
mlds_module_name::in, list(mlds_field_var_defn)::in,
io::di, io::uo) is det.
mlds_output_field_var_defns(_Opts, _Indent, _Separate, _ModuleName, [], !IO).
mlds_output_field_var_defns(Opts, Indent, Separate, ModuleName,
[FieldVarDefn | FieldVarDefns], !IO) :-
mlds_output_field_var_defn(Opts, Indent, Separate, ModuleName,
FieldVarDefn, !IO),
mlds_output_field_var_defns(Opts, Indent, Separate, ModuleName,
FieldVarDefns, !IO).
:- pred mlds_output_field_var_defn(mlds_to_c_opts::in, indent::in, bool::in,
mlds_module_name::in, mlds_field_var_defn::in, io::di, io::uo) is det.
mlds_output_field_var_defn(Opts, Indent, Separate, ModuleName,
FieldVarDefn, !IO) :-
FieldVarDefn = mlds_field_var_defn(FieldVarName, Context, Flags,
Type, Initializer, GCStmt),
(
Separate = yes,
io.nl(!IO)
;
Separate = no
),
c_output_context(Opts ^ m2co_line_numbers, Context, !IO),
output_n_indents(Indent, !IO),
mlds_output_field_var_decl_flags(Opts, Flags, definition, !IO),
QualFieldVarName =
qual_field_var_name(ModuleName, module_qual, FieldVarName),
mlds_output_field_var_decl(Opts, QualFieldVarName, Type,
get_initializer_array_size(Initializer), !IO),
mlds_output_initializer(Opts, Type, Initializer, !IO),
io.write_string(";\n", !IO),
mlds_output_gc_statement(Opts, Indent, GCStmt, "", !IO).
%---------------------------------------------------------------------------%
% Output the definitions of the enumeration constants
% for an enumeration type.
%
:- pred mlds_output_enum_constants(mlds_to_c_opts::in, indent::in,
mlds_module_name::in, list(mlds_field_var_defn)::in, io::di, io::uo)
is det.
mlds_output_enum_constants(Opts, Indent, EnumModuleName, MemberFields, !IO) :-
% Select the enumeration constants from the list of members
% for this enumeration type, and output them.
list.filter(field_var_defn_is_enum_const, MemberFields,
EnumConstMemberFields),
io.write_list(EnumConstMemberFields, ",\n",
mlds_output_enum_constant(Opts, Indent, EnumModuleName), !IO),
io.nl(!IO).
% Output the definition of a single enumeration constant.
%
:- pred mlds_output_enum_constant(mlds_to_c_opts::in, indent::in,
mlds_module_name::in, mlds_field_var_defn::in, io::di, io::uo) is det.
mlds_output_enum_constant(Opts, Indent, EnumModuleName, FieldVarDefn, !IO) :-
FieldVarDefn = mlds_field_var_defn(FieldVarName, Context, _Flags,
Type, Initializer, _GCStmt),
c_output_context(Opts ^ m2co_line_numbers, Context, !IO),
output_n_indents(Indent, !IO),
QualFieldVarName =
qual_field_var_name(EnumModuleName, type_qual, FieldVarName),
mlds_output_fully_qualified_field_var_name(QualFieldVarName, !IO),
mlds_output_initializer(Opts, Type, Initializer, !IO).
%---------------------------------------------------------------------------%
:- pred mlds_output_field_var_decl_flags(mlds_to_c_opts::in,
mlds_field_var_decl_flags::in, decl_or_defn::in, io::di, io::uo) is det.
mlds_output_field_var_decl_flags(Opts, Flags, DeclOrDefn, !IO) :-
Constness = Flags ^ mfvdf_constness,
Comments = Opts ^ m2co_auto_comments,
(
Comments = yes,
% XXX We used to call mlds_output_extern_or_static
% on mlds_data_decl_flags. This predicate pays attention to PerInstance
% *only* when the access flag is acc_local, while field var's
% access flags were always acc_public (which is why we do not need
% to explicitly store that flag).
PerInstance = Flags ^ mfvdf_per_instance,
mlds_output_per_instance_comment(PerInstance, !IO)
;
Comments = no
),
(
DeclOrDefn = forward_decl,
io.write_string("extern ", !IO)
;
DeclOrDefn = definition
),
mlds_output_constness(Constness, !IO).
:- pred mlds_output_class_decl_flags(mlds_to_c_opts::in,
mlds_class_decl_flags::in, decl_or_defn::in, io::di, io::uo) is det.
mlds_output_class_decl_flags(Opts, Flags, _DeclOrDefn, !IO) :-
Flags = mlds_class_decl_flags(Access, Overridability, Constness),
Comments = Opts ^ m2co_auto_comments,
(
Comments = yes,
(
Access = class_public,
io.write_string("/* public: */ ", !IO)
;
Access = class_private,
io.write_string("/* private: */ ", !IO)
),
io.write_string("/* one_copy */ ", !IO)
;
Comments = no
),
(
Overridability = overridable
;
Overridability = sealed,
io.write_string("/* sealed */ ", !IO)
),
mlds_output_constness(Constness, !IO).
:- pred mlds_output_per_instance_comment(per_instance::in,
io::di, io::uo) is det.
mlds_output_per_instance_comment(per_instance, !IO).
mlds_output_per_instance_comment(one_copy, !IO) :-
io.write_string("/* one_copy */ ", !IO).
:- pred mlds_output_constness(constness::in, io::di, io::uo) is det.
mlds_output_constness(const, !IO) :-
io.write_string("const ", !IO).
mlds_output_constness(modifiable, !IO).
%---------------------------------------------------------------------------%
:- end_module ml_backend.mlds_to_c_class.
%---------------------------------------------------------------------------%