1 //===- ModuleLoader.h - Module Loader Interface -----------------*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file defines the ModuleLoader interface, which is responsible for
11 // loading named modules.
13 //===----------------------------------------------------------------------===//
15 #ifndef LLVM_CLANG_LEX_MODULELOADER_H
16 #define LLVM_CLANG_LEX_MODULELOADER_H
18 #include "clang/Basic/LLVM.h"
19 #include "clang/Basic/Module.h"
20 #include "clang/Basic/SourceLocation.h"
21 #include "llvm/ADT/ArrayRef.h"
22 #include "llvm/ADT/PointerIntPair.h"
23 #include "llvm/ADT/StringRef.h"
28 class GlobalModuleIndex;
31 /// A sequence of identifier/location pairs used to describe a particular
32 /// module or submodule, e.g., std.vector.
33 using ModuleIdPath = ArrayRef<std::pair<IdentifierInfo *, SourceLocation>>;
35 /// Describes the result of attempting to load a module.
36 class ModuleLoadResult {
39 // We either succeeded or failed to load the named module.
42 // The module exists, but does not actually contain the named submodule.
43 // This should only happen if the named submodule was inferred from an
44 // umbrella directory, but not actually part of the umbrella header.
47 // The module exists but cannot be imported due to a configuration mismatch.
50 llvm::PointerIntPair<Module *, 2, LoadResultKind> Storage;
52 ModuleLoadResult() = default;
53 ModuleLoadResult(Module *M) : Storage(M, Normal) {}
54 ModuleLoadResult(LoadResultKind Kind) : Storage(nullptr, Kind) {}
56 operator Module *() const { return Storage.getPointer(); }
58 /// Determines whether the module, which failed to load, was
59 /// actually a submodule that we expected to see (based on implying the
60 /// submodule from header structure), but didn't materialize in the actual
62 bool isMissingExpected() const { return Storage.getInt() == MissingExpected; }
64 /// Determines whether the module failed to load due to a configuration
65 /// mismatch with an explicitly-named .pcm file from the command line.
66 bool isConfigMismatch() const { return Storage.getInt() == ConfigMismatch; }
69 /// Abstract interface for a module loader.
71 /// This abstract interface describes a module loader, which is responsible
72 /// for resolving a module name (e.g., "std") to an actual module file, and
73 /// then loading that module.
75 // Building a module if true.
79 explicit ModuleLoader(bool BuildingModule = false)
80 : BuildingModule(BuildingModule) {}
82 virtual ~ModuleLoader();
84 /// Returns true if this instance is building a module.
85 bool buildingModule() const {
86 return BuildingModule;
89 /// Flag indicating whether this instance is building a module.
90 void setBuildingModule(bool BuildingModuleFlag) {
91 BuildingModule = BuildingModuleFlag;
94 /// Attempt to load the given module.
96 /// This routine attempts to load the module described by the given
99 /// \param ImportLoc The location of the 'import' keyword.
101 /// \param Path The identifiers (and their locations) of the module
102 /// "path", e.g., "std.vector" would be split into "std" and "vector".
104 /// \param Visibility The visibility provided for the names in the loaded
107 /// \param IsInclusionDirective Indicates that this module is being loaded
108 /// implicitly, due to the presence of an inclusion directive. Otherwise,
109 /// it is being loaded due to an import declaration.
111 /// \returns If successful, returns the loaded module. Otherwise, returns
112 /// NULL to indicate that the module could not be loaded.
113 virtual ModuleLoadResult loadModule(SourceLocation ImportLoc,
115 Module::NameVisibilityKind Visibility,
116 bool IsInclusionDirective) = 0;
118 /// Attempt to load the given module from the specified source buffer. Does
119 /// not make any submodule visible; for that, use loadModule or
120 /// makeModuleVisible.
122 /// \param Loc The location at which the module was loaded.
123 /// \param ModuleName The name of the module to build.
124 /// \param Source The source of the module: a (preprocessed) module map.
125 virtual void loadModuleFromSource(SourceLocation Loc, StringRef ModuleName,
126 StringRef Source) = 0;
128 /// Make the given module visible.
129 virtual void makeModuleVisible(Module *Mod,
130 Module::NameVisibilityKind Visibility,
131 SourceLocation ImportLoc) = 0;
133 /// Load, create, or return global module.
134 /// This function returns an existing global module index, if one
135 /// had already been loaded or created, or loads one if it
136 /// exists, or creates one if it doesn't exist.
137 /// Also, importantly, if the index doesn't cover all the modules
138 /// in the module map, it will be update to do so here, because
139 /// of its use in searching for needed module imports and
140 /// associated fixit messages.
141 /// \param TriggerLoc The location for what triggered the load.
142 /// \returns Returns null if load failed.
143 virtual GlobalModuleIndex *loadGlobalModuleIndex(
144 SourceLocation TriggerLoc) = 0;
146 /// Check global module index for missing imports.
147 /// \param Name The symbol name to look for.
148 /// \param TriggerLoc The location for what triggered the load.
149 /// \returns Returns true if any modules with that symbol found.
150 virtual bool lookupMissingImports(StringRef Name,
151 SourceLocation TriggerLoc) = 0;
153 bool HadFatalFailure = false;
156 /// A module loader that doesn't know how to load modules.
157 class TrivialModuleLoader : public ModuleLoader {
159 ModuleLoadResult loadModule(SourceLocation ImportLoc, ModuleIdPath Path,
160 Module::NameVisibilityKind Visibility,
161 bool IsInclusionDirective) override {
165 void loadModuleFromSource(SourceLocation ImportLoc, StringRef ModuleName,
166 StringRef Source) override {}
168 void makeModuleVisible(Module *Mod, Module::NameVisibilityKind Visibility,
169 SourceLocation ImportLoc) override {}
171 GlobalModuleIndex *loadGlobalModuleIndex(SourceLocation TriggerLoc) override {
175 bool lookupMissingImports(StringRef Name,
176 SourceLocation TriggerLoc) override {
183 #endif // LLVM_CLANG_LEX_MODULELOADER_H