1327952Sdim//===- ModuleLoader.h - Module Loader Interface -----------------*- C++ -*-===// 2226586Sdim// 3353358Sdim// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4353358Sdim// See https://llvm.org/LICENSE.txt for license information. 5353358Sdim// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6226586Sdim// 7226586Sdim//===----------------------------------------------------------------------===// 8226586Sdim// 9341825Sdim// This file defines the ModuleLoader interface, which is responsible for 10226586Sdim// loading named modules. 11226586Sdim// 12226586Sdim//===----------------------------------------------------------------------===// 13327952Sdim 14280031Sdim#ifndef LLVM_CLANG_LEX_MODULELOADER_H 15280031Sdim#define LLVM_CLANG_LEX_MODULELOADER_H 16226586Sdim 17327952Sdim#include "clang/Basic/LLVM.h" 18234353Sdim#include "clang/Basic/Module.h" 19226586Sdim#include "clang/Basic/SourceLocation.h" 20234353Sdim#include "llvm/ADT/ArrayRef.h" 21249423Sdim#include "llvm/ADT/PointerIntPair.h" 22327952Sdim#include "llvm/ADT/StringRef.h" 23327952Sdim#include <utility> 24226586Sdim 25226586Sdimnamespace clang { 26226586Sdim 27276479Sdimclass GlobalModuleIndex; 28226586Sdimclass IdentifierInfo; 29249423Sdim 30341825Sdim/// A sequence of identifier/location pairs used to describe a particular 31234353Sdim/// module or submodule, e.g., std.vector. 32327952Sdimusing ModuleIdPath = ArrayRef<std::pair<IdentifierInfo *, SourceLocation>>; 33249423Sdim 34341825Sdim/// Describes the result of attempting to load a module. 35249423Sdimclass ModuleLoadResult { 36314564Sdimpublic: 37314564Sdim enum LoadResultKind { 38314564Sdim // We either succeeded or failed to load the named module. 39314564Sdim Normal, 40327952Sdim 41314564Sdim // The module exists, but does not actually contain the named submodule. 42314564Sdim // This should only happen if the named submodule was inferred from an 43314564Sdim // umbrella directory, but not actually part of the umbrella header. 44314564Sdim MissingExpected, 45327952Sdim 46314564Sdim // The module exists but cannot be imported due to a configuration mismatch. 47360784Sdim ConfigMismatch, 48360784Sdim 49360784Sdim // We failed to load the module, but we shouldn't cache the failure. 50360784Sdim OtherUncachedFailure, 51314564Sdim }; 52314564Sdim llvm::PointerIntPair<Module *, 2, LoadResultKind> Storage; 53249423Sdim 54327952Sdim ModuleLoadResult() = default; 55314564Sdim ModuleLoadResult(Module *M) : Storage(M, Normal) {} 56314564Sdim ModuleLoadResult(LoadResultKind Kind) : Storage(nullptr, Kind) {} 57249423Sdim 58249423Sdim operator Module *() const { return Storage.getPointer(); } 59249423Sdim 60360784Sdim /// Determines whether this is a normal return, whether or not loading the 61360784Sdim /// module was successful. 62360784Sdim bool isNormal() const { return Storage.getInt() == Normal; } 63360784Sdim 64341825Sdim /// Determines whether the module, which failed to load, was 65249423Sdim /// actually a submodule that we expected to see (based on implying the 66249423Sdim /// submodule from header structure), but didn't materialize in the actual 67249423Sdim /// module. 68314564Sdim bool isMissingExpected() const { return Storage.getInt() == MissingExpected; } 69314564Sdim 70341825Sdim /// Determines whether the module failed to load due to a configuration 71314564Sdim /// mismatch with an explicitly-named .pcm file from the command line. 72314564Sdim bool isConfigMismatch() const { return Storage.getInt() == ConfigMismatch; } 73249423Sdim}; 74249423Sdim 75341825Sdim/// Abstract interface for a module loader. 76226586Sdim/// 77226586Sdim/// This abstract interface describes a module loader, which is responsible 78226586Sdim/// for resolving a module name (e.g., "std") to an actual module file, and 79226586Sdim/// then loading that module. 80226586Sdimclass ModuleLoader { 81276479Sdim // Building a module if true. 82276479Sdim bool BuildingModule; 83327952Sdim 84226586Sdimpublic: 85327952Sdim explicit ModuleLoader(bool BuildingModule = false) 86327952Sdim : BuildingModule(BuildingModule) {} 87261991Sdim 88226586Sdim virtual ~ModuleLoader(); 89341825Sdim 90341825Sdim /// Returns true if this instance is building a module. 91276479Sdim bool buildingModule() const { 92276479Sdim return BuildingModule; 93276479Sdim } 94327952Sdim 95341825Sdim /// Flag indicating whether this instance is building a module. 96276479Sdim void setBuildingModule(bool BuildingModuleFlag) { 97276479Sdim BuildingModule = BuildingModuleFlag; 98276479Sdim } 99341825Sdim 100341825Sdim /// Attempt to load the given module. 101226586Sdim /// 102341825Sdim /// This routine attempts to load the module described by the given 103360784Sdim /// parameters. If there is a module cache, this may implicitly compile the 104360784Sdim /// module before loading it. 105226586Sdim /// 106226586Sdim /// \param ImportLoc The location of the 'import' keyword. 107226586Sdim /// 108234353Sdim /// \param Path The identifiers (and their locations) of the module 109234353Sdim /// "path", e.g., "std.vector" would be split into "std" and "vector". 110341825Sdim /// 111234353Sdim /// \param Visibility The visibility provided for the names in the loaded 112234353Sdim /// module. 113234353Sdim /// 114234353Sdim /// \param IsInclusionDirective Indicates that this module is being loaded 115234353Sdim /// implicitly, due to the presence of an inclusion directive. Otherwise, 116234353Sdim /// it is being loaded due to an import declaration. 117234353Sdim /// 118341825Sdim /// \returns If successful, returns the loaded module. Otherwise, returns 119234353Sdim /// NULL to indicate that the module could not be loaded. 120249423Sdim virtual ModuleLoadResult loadModule(SourceLocation ImportLoc, 121249423Sdim ModuleIdPath Path, 122249423Sdim Module::NameVisibilityKind Visibility, 123249423Sdim bool IsInclusionDirective) = 0; 124249423Sdim 125360784Sdim /// Attempt to create the given module from the specified source buffer. 126360784Sdim /// Does not load the module or make any submodule visible; for that, use 127360784Sdim /// loadModule and makeModuleVisible. 128321369Sdim /// 129360784Sdim /// \param Loc The location at which to create the module. 130360784Sdim /// \param ModuleName The name of the module to create. 131321369Sdim /// \param Source The source of the module: a (preprocessed) module map. 132360784Sdim virtual void createModuleFromSource(SourceLocation Loc, StringRef ModuleName, 133360784Sdim StringRef Source) = 0; 134321369Sdim 135341825Sdim /// Make the given module visible. 136249423Sdim virtual void makeModuleVisible(Module *Mod, 137249423Sdim Module::NameVisibilityKind Visibility, 138288943Sdim SourceLocation ImportLoc) = 0; 139261991Sdim 140341825Sdim /// Load, create, or return global module. 141276479Sdim /// This function returns an existing global module index, if one 142276479Sdim /// had already been loaded or created, or loads one if it 143276479Sdim /// exists, or creates one if it doesn't exist. 144276479Sdim /// Also, importantly, if the index doesn't cover all the modules 145276479Sdim /// in the module map, it will be update to do so here, because 146276479Sdim /// of its use in searching for needed module imports and 147276479Sdim /// associated fixit messages. 148276479Sdim /// \param TriggerLoc The location for what triggered the load. 149276479Sdim /// \returns Returns null if load failed. 150276479Sdim virtual GlobalModuleIndex *loadGlobalModuleIndex( 151276479Sdim SourceLocation TriggerLoc) = 0; 152276479Sdim 153276479Sdim /// Check global module index for missing imports. 154276479Sdim /// \param Name The symbol name to look for. 155276479Sdim /// \param TriggerLoc The location for what triggered the load. 156276479Sdim /// \returns Returns true if any modules with that symbol found. 157276479Sdim virtual bool lookupMissingImports(StringRef Name, 158276479Sdim SourceLocation TriggerLoc) = 0; 159276479Sdim 160327952Sdim bool HadFatalFailure = false; 161226586Sdim}; 162321369Sdim 163360784Sdim/// A module loader that doesn't know how to create or load modules. 164321369Sdimclass TrivialModuleLoader : public ModuleLoader { 165321369Sdimpublic: 166321369Sdim ModuleLoadResult loadModule(SourceLocation ImportLoc, ModuleIdPath Path, 167321369Sdim Module::NameVisibilityKind Visibility, 168321369Sdim bool IsInclusionDirective) override { 169327952Sdim return {}; 170321369Sdim } 171321369Sdim 172360784Sdim void createModuleFromSource(SourceLocation ImportLoc, StringRef ModuleName, 173360784Sdim StringRef Source) override {} 174321369Sdim 175321369Sdim void makeModuleVisible(Module *Mod, Module::NameVisibilityKind Visibility, 176321369Sdim SourceLocation ImportLoc) override {} 177321369Sdim 178321369Sdim GlobalModuleIndex *loadGlobalModuleIndex(SourceLocation TriggerLoc) override { 179321369Sdim return nullptr; 180321369Sdim } 181327952Sdim 182321369Sdim bool lookupMissingImports(StringRef Name, 183321369Sdim SourceLocation TriggerLoc) override { 184327952Sdim return false; 185321369Sdim } 186321369Sdim}; 187341825Sdim 188327952Sdim} // namespace clang 189226586Sdim 190327952Sdim#endif // LLVM_CLANG_LEX_MODULELOADER_H 191