Files
mercury/compiler/add_foreign_enum.m
2026-01-15 05:52:08 +11:00

614 lines
26 KiB
Mathematica

%---------------------------------------------------------------------------%
% vim: ft=mercury ts=4 sw=4 et
%---------------------------------------------------------------------------%
% Copyright (C) 2015-2026 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.
%---------------------------------------------------------------------------%
%
% This module has two related but separate tasks.
%
% The task of the first part of this module is to check foreign_enum pragmas
% and gather from them the information that du_type_layout.m will use
% to help decide the representations of the types named in those pragmas.
%
% The task of the second part of this module is to check foreign_export_enum
% pragmas, and to record the information from the correct ones in the
% module_info for the code generator to use.
%
% The third part of the module consists of some utility predicates
% used by both of the previous parts, many of which are predicates that
% generate error messages.
%
%---------------------------------------------------------------------------%
:- module hlds.add_foreign_enum.
:- interface.
:- import_module hlds.hlds_data.
:- import_module hlds.hlds_module.
:- import_module hlds.status.
:- import_module libs.
:- import_module libs.globals.
:- import_module parse_tree.
:- import_module parse_tree.error_spec.
:- import_module parse_tree.prog_data.
:- import_module parse_tree.prog_item.
:- import_module list.
:- import_module map.
:- import_module maybe.
%---------------------------------------------------------------------------%
:- type du_ctor_to_tag_map == map(du_ctor, cons_tag).
:- type type_ctor_foreign_enums
---> type_ctor_foreign_enums(
tcfe_lang_contexts :: map(foreign_language, prog_context),
tcfe_tag_values :: maybe({du_ctor_to_tag_map,
foreign_language})
).
:- type type_ctor_to_foreign_enums_map
== map(type_ctor, type_ctor_foreign_enums).
% Check the given foreign_enum pragma for correctness.
% If it is correct, update the given type_ctor_to_foreign_enums_map
% with its information. If not, add the applicable error message(s)
% to the list.
%
:- pred add_pragma_foreign_enum(module_info::in,
{item_mercury_status, item_foreign_enum_info}::in,
type_ctor_to_foreign_enums_map::in, type_ctor_to_foreign_enums_map::out,
list(error_spec)::in, list(error_spec)::out) is det.
%---------------------------------------------------------------------------%
% Check the given foreign_export_enum pragma for correctness.
% If it is correct, record its information in the exported_enums field
% of the module_info so that the code generator can include the
% exported information in the target language file it emits
% (when compiling for the applicable backend). If it is not correct,
% add the applicable error message(s) to the list.
%
:- pred add_pragma_foreign_export_enum(item_foreign_export_enum_info::in,
module_info::in, module_info::out,
list(error_spec)::in, list(error_spec)::out) is det.
%---------------------------------------------------------------------------%
:- implementation.
:- import_module backend_libs.
:- import_module backend_libs.c_util.
:- import_module mdbcomp.
:- import_module mdbcomp.sym_name.
:- import_module parse_tree.check_type_inst_mode_defns.
:- import_module parse_tree.parse_tree_out_misc.
:- import_module parse_tree.prog_data_foreign.
:- import_module parse_tree.prog_foreign_enum.
:- import_module assoc_list.
:- import_module bimap.
:- import_module bool.
:- import_module cord.
:- import_module one_or_more.
:- import_module pair.
:- import_module require.
:- import_module set_tree234.
:- import_module string.
%---------------------------------------------------------------------------%
%---------------------------------------------------------------------------%
%
% Part 1: the implementation of foreign_enums.
%
add_pragma_foreign_enum(ModuleInfo, ImsItem, !TypeCtorForeignEnumMap,
Specs0, Specs) :-
ImsItem = {ItemMercuryStatus, ItemForeignEnum},
ItemForeignEnum = item_foreign_enum_info(Lang, TypeCtor,
OoMMercuryForeignTagPairs, Context, _SeqNum),
item_mercury_status_to_type_status(ItemMercuryStatus, PragmaStatus),
TypeCtor = type_ctor(TypeSymName, TypeArity),
TypeSNA = sym_name_arity(TypeSymName, TypeArity),
ContextPieces = [words("In"), pragma_decl("foreign_enum"),
words("declaration for type"), qual_type_ctor(TypeCtor),
suffix(":"), nl],
some [!Specs] (
!:Specs = [],
report_if_builtin_type(Context, "foreign_enum", TypeCtor, !Specs),
module_info_get_type_table(ModuleInfo, TypeTable),
( if search_type_ctor_defn(TypeTable, TypeCtor, TypeDefn) then
% If the type is in the type table (i.e. it is neither
% a builtin type such as int nor a reference to an undefined type),
% then TypeSymName should have been qualified by now.
(
TypeSymName = qualified(TypeModuleName, _TypeName)
;
TypeSymName = unqualified(_),
unexpected($pred, "unqualified type name for foreign_enum")
),
get_type_defn_status(TypeDefn, TypeStatus),
% Either both the type and the pragma are defined in this module,
% or they are both imported. Any other combination is illegal.
IsTypeLocal = type_status_defined_in_this_module(TypeStatus),
( if
(
IsTypeLocal = yes,
( PragmaStatus = type_status(status_local)
; PragmaStatus =
type_status(status_exported_to_submodules)
)
;
IsTypeLocal = no,
type_status_is_imported(PragmaStatus) = yes
)
then
true
else if
PragmaStatus = type_status(status_exported)
then
% We should have filtered out foreign_enum pragmas
% in the interface section when we constructed the parse tree;
% this is just a sanity check.
unexpected($pred, "foreign_enum in the interface section")
else
% As of 2019 Sep 29, this should not happen anymore,
% since we now catch foreign_enum pragmas that refer
% to types in other modules when parsing them.
NotThisModulePieces = ContextPieces ++ [words("error:")] ++
color_as_subject([qual_sym_name_arity(TypeSNA)]) ++
[words("is")] ++
color_as_incorrect(
[words("not defined in this module.")]) ++
[nl],
NotThisModuleSpec = spec($pred, severity_error, phase_pt2h,
Context, NotThisModulePieces),
!:Specs = [NotThisModuleSpec | !.Specs]
),
get_type_defn_body(TypeDefn, TypeBody),
get_type_defn_context(TypeDefn, TypeDefnContext),
(
( TypeBody = hlds_eqv_type(_)
; TypeBody = hlds_abstract_type(_)
; TypeBody = hlds_solver_type(_)
; TypeBody = hlds_foreign_type(_)
),
report_not_enum_type_non_du(for_foreign_enum, TypeCtor,
TypeBody, TypeDefnContext, Context, !Specs)
;
TypeBody = hlds_du_type(TypeBodyDu),
TypeBodyDu = type_body_du(Ctors, _AlphaSortedCtors,
MaybeSuperType, _MaybeUserEq, MaybeRepn, _IsForeignType),
expect(unify(MaybeSuperType, not_a_subtype), $pred,
"MaybeSuperType != no"),
expect(unify(MaybeRepn, no), $pred,
"MaybeRepn != no"),
MercuryForeignTagPairs =
one_or_more_to_list(OoMMercuryForeignTagPairs),
build_mercury_foreign_map(TypeModuleName, TypeCtor,
TypeDefnContext, for_foreign_enum, Context, ContextPieces,
one_or_more_to_list(Ctors),
MercuryForeignTagPairs, MercuryForeignTagBimap, !Specs),
MercuryForeignTagNames =
bimap.to_assoc_list(MercuryForeignTagBimap),
list.map(
map_du_ctor_to_foreign_tag(TypeCtor, TypeModuleName,
Lang),
MercuryForeignTagNames, DuCtorForeignTags),
% Converting each name to a du_ctor would preserve the order,
% but bimap.to_assoc_list does not guarantee an order,
% and unlike map.m, bimap.m does not have to_sorted_assoc_list.
map.from_assoc_list(DuCtorForeignTags, DuCtorToTagMap),
% Work out what language's foreign_enum pragma we should be
% looking at for the current compilation target language.
module_info_get_globals(ModuleInfo, Globals),
globals.get_target(Globals, TargetLanguage),
LangForForeignEnums =
target_lang_to_foreign_enum_lang(TargetLanguage),
( if
Lang = LangForForeignEnums,
!.Specs = []
then
MaybeTagValuesToSet = yes({DuCtorToTagMap, Lang})
else
MaybeTagValuesToSet = no
),
( if map.search(!.TypeCtorForeignEnumMap, TypeCtor, TCFE0) then
TCFE0 = type_ctor_foreign_enums(LangContextMap0,
_OldMaybeTagValues),
( if map.search(LangContextMap0, Lang, OldContext) then
maybe_add_duplicate_foreign_enum_error(TypeCtor, Lang,
PragmaStatus, OldContext, Context, !Specs),
TCFE1 = TCFE0
else
map.det_insert(Lang, Context,
LangContextMap0, LangContextMap),
TCFE1 = TCFE0 ^ tcfe_lang_contexts := LangContextMap
),
(
MaybeTagValuesToSet = no,
TCFE = TCFE1
;
MaybeTagValuesToSet = yes(_),
TCFE = TCFE1 ^ tcfe_tag_values := MaybeTagValuesToSet
),
map.det_update(TypeCtor, TCFE, !TypeCtorForeignEnumMap)
else
LangContextMap = map.singleton(Lang, Context),
TCFE = type_ctor_foreign_enums(LangContextMap,
MaybeTagValuesToSet),
map.det_insert(TypeCtor, TCFE, !TypeCtorForeignEnumMap)
)
)
else
% This else-branch corresponds to an undefined type. We do not
% issue an error message for it here, since module qualification
% will have already done so.
true
),
Specs = !.Specs ++ Specs0
).
% For a given target language work out which language's foreign_enum
% pragma we should be looking at.
%
:- func target_lang_to_foreign_enum_lang(compilation_target)
= foreign_language.
target_lang_to_foreign_enum_lang(target_c) = lang_c.
target_lang_to_foreign_enum_lang(target_csharp) = lang_csharp.
target_lang_to_foreign_enum_lang(target_java) = lang_java.
:- pred map_du_ctor_to_foreign_tag(type_ctor::in, module_name::in,
foreign_language::in,
pair(string, string)::in, pair(du_ctor, cons_tag)::out) is det.
map_du_ctor_to_foreign_tag(TypeCtor, TypeModuleName, ForeignLanguage,
CtorName - ForeignTagName, DuCtor - ForeignTag) :-
CtorSymName = qualified(TypeModuleName, CtorName),
DuCtor = du_ctor(CtorSymName, 0, TypeCtor),
ForeignTag = foreign_tag(ForeignLanguage, ForeignTagName).
%---------------------------------------------------------------------------%
%---------------------------------------------------------------------------%
%
% Part 2: the implementation of foreign_export_enums.
%
add_pragma_foreign_export_enum(ItemForeignExportEnum, !ModuleInfo,
Specs0, Specs) :-
ItemForeignExportEnum = item_foreign_export_enum_info(Lang, TypeCtor,
Attributes, Overrides, Context, _SeqNum),
TypeCtor = type_ctor(TypeSymName, _TypeArity),
ContextPieces = [words("In"), pragma_decl("foreign_export_enum"),
words("declaration for type"), qual_type_ctor(TypeCtor),
suffix(":"), nl],
some [!Specs] (
!:Specs = [],
report_if_builtin_type(Context, "foreign_export_enum", TypeCtor,
!Specs),
module_info_get_type_table(!.ModuleInfo, TypeTable),
( if search_type_ctor_defn(TypeTable, TypeCtor, TypeDefn) then
% If the type is in the type table (i.e. it is neither
% a builtin type such as int nor a reference to an undefined type),
% then TypeSymName should have been qualified by now.
(
TypeSymName = qualified(TypeModuleName, _TypeName)
;
TypeSymName = unqualified(_),
unexpected($pred,
"unqualified type name for foreign_export_enum")
),
get_type_defn_body(TypeDefn, TypeBody),
get_type_defn_context(TypeDefn, TypeDefnContext),
(
( TypeBody = hlds_eqv_type(_)
; TypeBody = hlds_abstract_type(_)
; TypeBody = hlds_solver_type(_)
; TypeBody = hlds_foreign_type(_)
),
report_not_enum_type_non_du(for_foreign_export_enum,
TypeCtor, TypeBody, TypeDefnContext, Context, !Specs)
;
TypeBody = hlds_du_type(TypeBodyDu),
TypeBodyDu = type_body_du(Ctors, _AlphaSortedCtors,
MaybeSuperType, _MaybeUserEq, MaybeRepn, _IsForeignType),
expect(unify(MaybeSuperType, not_a_subtype), $pred,
"MaybeSuperType != no"),
(
MaybeRepn = no,
unexpected($pred, "MaybeRepn = no")
;
MaybeRepn = yes(Repn),
CtorRepns = Repn ^ dur_ctor_repns
),
build_mercury_foreign_map(TypeModuleName, TypeCtor,
TypeDefnContext, for_foreign_export_enum,
Context, ContextPieces, one_or_more_to_list(Ctors),
Overrides, OverrideBimap, !Specs),
OverrideMap = bimap.forward_map(OverrideBimap),
Attributes =
export_enum_attributes(MaybePrefix, MakeUpperCase),
(
MaybePrefix = yes(Prefix)
;
MaybePrefix = no,
Prefix = ""
),
build_export_enum_name_map(ContextPieces, Context, Lang,
Prefix, MakeUpperCase, OverrideMap, CtorRepns,
NameMap, !Specs),
(
!.Specs = [],
ExportedEnum = exported_enum_info(TypeCtor, CtorRepns,
Lang, NameMap, Context),
module_info_get_exported_enums(!.ModuleInfo,
ExportedEnums0),
ExportedEnums = [ExportedEnum | ExportedEnums0],
module_info_set_exported_enums(ExportedEnums,
!ModuleInfo)
;
!.Specs = [_ | _]
)
)
else
% This case corresponds to an undefined type. We do not issue
% an error message for it here, since module qualification
% will have already done so.
true
),
Specs = !.Specs ++ Specs0
).
:- pred build_export_enum_name_map(list(format_piece)::in,
prog_context::in, foreign_language::in, string::in,
uppercase_export_enum::in, map(string, string)::in,
list(constructor_repn)::in, map(string, string)::out,
list(error_spec)::in, list(error_spec)::out) is det.
build_export_enum_name_map(ContextPieces, Context, Lang, Prefix, MakeUpperCase,
OverrideMap, CtorRepns, NameMap, !Specs) :-
list.foldl2(
add_ctor_to_name_map(Lang, Prefix, MakeUpperCase, OverrideMap),
CtorRepns, map.init, NameMap, cord.init, BadForeignNamesCord),
BadForeignNames = cord.to_list(BadForeignNamesCord),
(
BadForeignNames = []
;
BadForeignNames = [_ | _],
% NOTE If you ever need to add a new Lang here, you many also need to
% - update the code of add_ctor_to_name_map, and
% - update the wording of the diagnostic below to include the name
% of the language.
(
Lang = lang_c,
_LangName = "C"
;
Lang = lang_java,
_LangName = "Java"
;
Lang = lang_csharp,
_LangName = "C#"
),
MakeBFNPieces = (func(BadForeignName) = [quote(BadForeignName)]),
BadForeignPiecesList = list.map(MakeBFNPieces, BadForeignNames),
BadForeignPieces = pieces_list_to_color_line_pieces(color_incorrect,
[suffix(".")], BadForeignPiecesList),
Pieces = ContextPieces ++
[words("error: some of the constructors of the type")] ++
color_as_incorrect([words("cannot be converted")]) ++
[words("into valid identifiers")] ++
% Omitting the identity of the target language eliminates
% the need for separate .err_exp files for each language
% for test cases that test this diagnostic. But please also
% see the comment above.
% [words("for"), words(_LangName)] ++
[suffix("."), nl,
words("The problematic foreign"),
words(choose_number(BadForeignNames, "name is:", "names are:")),
nl_indent_delta(1)] ++
BadForeignPieces ++
[nl_indent_delta(-1)],
Spec = spec($pred, severity_error, phase_pt2h, Context, Pieces),
!:Specs = [Spec | !.Specs]
).
:- pred add_ctor_to_name_map(foreign_language::in, string::in,
uppercase_export_enum::in, map(string, string)::in, constructor_repn::in,
map(string, string)::in, map(string, string)::out,
cord(string)::in, cord(string)::out) is det.
add_ctor_to_name_map(_Lang, Prefix, MakeUpperCase, OverrideMap, CtorRepn,
!NameMap, !BadForeignNames) :-
% NOTE We ignore the language parameter because all three of the
% currently available target languages, C, Java and C#, use the
% same rules for what is a valid identifier.
CtorSymName = CtorRepn ^ cr_name,
CtorName = unqualify_name(CtorSymName),
% If the user specified a name for this constructor, then use that.
( if map.search(OverrideMap, CtorName, UserForeignName) then
ForeignNameTail = UserForeignName
else
% Otherwise derive a name automatically from the constructor name.
(
MakeUpperCase = uppercase_export_enum,
ForeignNameTail = string.to_upper(CtorName)
;
MakeUpperCase = do_not_uppercase_export_enum,
ForeignNameTail = CtorName
)
),
ForeignName = Prefix ++ ForeignNameTail,
IsValidForeignName = pred_to_bool(is_valid_c_identifier(ForeignName)),
(
IsValidForeignName = yes,
map.det_insert(CtorName, ForeignName, !NameMap)
;
IsValidForeignName = no,
cord.snoc(ForeignName, !BadForeignNames)
).
%---------------------------------------------------------------------------%
%---------------------------------------------------------------------------%
%
% Part 3: utilities that help implement both foreign_enums and
% foreign_export_enums.
%
:- pred build_mercury_foreign_map(module_name::in, type_ctor::in,
prog_context::in, for_fe_or_fee::in,
prog_context::in, list(format_piece)::in, list(constructor)::in,
assoc_list(sym_name, string)::in, bimap(string, string)::out,
list(error_spec)::in, list(error_spec)::out) is det.
build_mercury_foreign_map(TypeModuleName, TypeCtor, TypeDefnContext, ForWhat,
Context, ContextPieces, Ctors, Overrides, OverrideMap, !Specs) :-
find_non_enum_ctors_build_valid_ctor_names(Ctors,
set_tree234.init, ValidCtorNames, cord.init, NonEnumSNAsCord),
NonEnumSNAs = cord.to_list(NonEnumSNAsCord),
(
NonEnumSNAs = []
;
NonEnumSNAs = [_ | _],
report_not_enum_type_du(ForWhat, TypeCtor, TypeDefnContext,
NonEnumSNAs, Context, !Specs)
),
build_ctor_name_to_foreign_name_map(ForWhat, Context, ContextPieces,
TypeModuleName, ValidCtorNames, Overrides, OverrideMap, !Specs).
% Please keep in sync with find_non_enum_ctors in
% check_type_inst_mode_defns.m.
%
:- pred find_non_enum_ctors_build_valid_ctor_names(list(constructor)::in,
set_tree234(string)::in, set_tree234(string)::out,
cord(sym_name_arity)::in, cord(sym_name_arity)::out) is det.
find_non_enum_ctors_build_valid_ctor_names([], !ValidNamesSet, !NonEnumSNAs).
find_non_enum_ctors_build_valid_ctor_names([Ctor | Ctors],
!ValidNamesSet, !NonEnumSNAs) :-
CtorSymName = Ctor ^ cons_name,
CtorArity = Ctor ^ cons_num_args,
( if CtorArity = 0 then
true
else
CtorSNA = sym_name_arity(CtorSymName, CtorArity),
cord.snoc(CtorSNA, !NonEnumSNAs)
),
CtorName = unqualify_name(CtorSymName),
set_tree234.insert(CtorName, !ValidNamesSet),
find_non_enum_ctors_build_valid_ctor_names(Ctors,
!ValidNamesSet, !NonEnumSNAs).
%---------------------------------------------------------------------------%
%---------------------------------------------------------------------------%
:- pred maybe_add_duplicate_foreign_enum_error(type_ctor::in,
foreign_language::in, type_status::in, prog_context::in, prog_context::in,
list(error_spec)::in, list(error_spec)::out) is det.
maybe_add_duplicate_foreign_enum_error(TypeCtor, Lang, PragmaStatus,
OldContext, Context, !Specs) :-
( if PragmaStatus = type_status(status_opt_imported) then
true
else
LangStr = mercury_foreign_language_to_string(Lang),
CurPieces = [words("Error:")] ++
color_as_incorrect([words("duplicate"),
pragma_decl("foreign_enum"), words("declaration")]) ++
[words("for")] ++
color_as_subject([words("type constructor"),
unqual_type_ctor(TypeCtor), words("and"),
words("target language"), fixed(LangStr), suffix(".")]) ++
[nl],
OldPieces = [words("The first foreign_enum pragma"), words("for"),
unqual_type_ctor(TypeCtor), words("and"), fixed(LangStr),
words("was here."), nl],
CurMsg = msg(Context, CurPieces),
OldMsg = msg(OldContext, OldPieces),
Spec = error_spec($pred, severity_error, phase_pt2h, [CurMsg, OldMsg]),
!:Specs = [Spec | !.Specs]
).
%---------------------------------------------------------------------------%
% Emit an error message for foreign_enum and foreign_export_enum pragmas
% for the builtin atomic types.
%
:- pred report_if_builtin_type(prog_context::in, string::in, type_ctor::in,
list(error_spec)::in, list(error_spec)::out) is det.
report_if_builtin_type(Context, DeclName, TypeCtor, !Specs) :-
TypeCtor = type_ctor(TypeSymName, TypeArity),
( if
is_builtin_type_sym_name(TypeSymName),
TypeArity = 0
then
Pieces =
[words("Error:"), pragma_decl(DeclName), words("declarations")] ++
color_as_incorrect([words("are not allowed")]) ++
[words("for builtin types such as")] ++
color_as_subject([unqual_type_ctor(TypeCtor), suffix(".")]) ++
[nl],
Spec = spec($pred, severity_error, phase_pt2h, Context, Pieces),
!:Specs = [Spec | !.Specs]
else
true
).
:- inst non_du_type_body for hlds_type_body/0
---> hlds_eqv_type(ground)
; hlds_foreign_type(ground)
; hlds_solver_type(ground)
; hlds_abstract_type(ground).
:- pred report_not_enum_type_non_du(for_fe_or_fee::in,
type_ctor::in, hlds_type_body::in(non_du_type_body), prog_context::in,
prog_context::in, list(error_spec)::in, list(error_spec)::out) is det.
report_not_enum_type_non_du(ForWhat, TypeCtor, TypeBody, TypeDefnContext,
EnumContext, !Specs) :-
(
TypeBody = hlds_eqv_type(_),
TypeKindDesc = "an equivalence type"
;
TypeBody = hlds_abstract_type(_),
TypeKindDesc = "an abstract type"
;
TypeBody = hlds_solver_type(_),
TypeKindDesc = "a solver type"
;
TypeBody = hlds_foreign_type(_),
TypeKindDesc = "a foreign type"
),
( ForWhat = for_foreign_enum, PragmaName = "foreign_enum"
; ForWhat = for_foreign_export_enum, PragmaName = "foreign_export_enum"
),
EnumPieces = [words("Error: the Mercury definition of")] ++
color_as_subject([qual_type_ctor(TypeCtor)]) ++
[words("is"), words(TypeKindDesc), suffix(","),
words("not an enumeration type, so")] ++
color_as_incorrect([words("there must not be any"),
pragma_decl(PragmaName), words("declarations for it.")]) ++ [nl],
TypePieces = [words("That Mercury definition is here."), nl],
Spec = error_spec($pred, severity_error, phase_pt2h,
[msg(EnumContext, EnumPieces), msg(TypeDefnContext, TypePieces)]),
!:Specs = [Spec | !.Specs].
%---------------------------------------------------------------------------%
:- end_module hlds.add_foreign_enum.
%---------------------------------------------------------------------------%