1 //===-- ASTMerge.cpp - AST Merging Frontend Action --------------*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 #include "clang/Frontend/ASTUnit.h"
9 #include "clang/AST/ASTContext.h"
10 #include "clang/AST/ASTDiagnostic.h"
11 #include "clang/AST/ASTImporter.h"
12 #include "clang/AST/ASTImporterSharedState.h"
13 #include "clang/Basic/Diagnostic.h"
14 #include "clang/Frontend/CompilerInstance.h"
15 #include "clang/Frontend/FrontendActions.h"
16 
17 using namespace clang;
18 
19 std::unique_ptr<ASTConsumer>
20 ASTMergeAction::CreateASTConsumer(CompilerInstance &CI, StringRef InFile) {
21   return AdaptedAction->CreateASTConsumer(CI, InFile);
22 }
23 
24 bool ASTMergeAction::BeginSourceFileAction(CompilerInstance &CI) {
25   // FIXME: This is a hack. We need a better way to communicate the
26   // AST file, compiler instance, and file name than member variables
27   // of FrontendAction.
28   AdaptedAction->setCurrentInput(getCurrentInput(), takeCurrentASTUnit());
29   AdaptedAction->setCompilerInstance(&CI);
30   return AdaptedAction->BeginSourceFileAction(CI);
31 }
32 
33 void ASTMergeAction::ExecuteAction() {
34   CompilerInstance &CI = getCompilerInstance();
35   CI.getDiagnostics().getClient()->BeginSourceFile(
36                                              CI.getASTContext().getLangOpts());
37   CI.getDiagnostics().SetArgToStringFn(&FormatASTNodeDiagnosticArgument,
38                                        &CI.getASTContext());
39   IntrusiveRefCntPtr<DiagnosticIDs>
40       DiagIDs(CI.getDiagnostics().getDiagnosticIDs());
41   auto SharedState = std::make_shared<ASTImporterSharedState>(
42       *CI.getASTContext().getTranslationUnitDecl());
43   for (unsigned I = 0, N = ASTFiles.size(); I != N; ++I) {
44     IntrusiveRefCntPtr<DiagnosticsEngine>
45         Diags(new DiagnosticsEngine(DiagIDs, &CI.getDiagnosticOpts(),
46                                     new ForwardingDiagnosticConsumer(
47                                           *CI.getDiagnostics().getClient()),
48                                     /*ShouldOwnClient=*/true));
49     std::unique_ptr<ASTUnit> Unit = ASTUnit::LoadFromASTFile(
50         ASTFiles[I], CI.getPCHContainerReader(), ASTUnit::LoadEverything, Diags,
51         CI.getFileSystemOpts(), false);
52 
53     if (!Unit)
54       continue;
55 
56     ASTImporter Importer(CI.getASTContext(), CI.getFileManager(),
57                          Unit->getASTContext(), Unit->getFileManager(),
58                          /*MinimalImport=*/false, SharedState);
59 
60     TranslationUnitDecl *TU = Unit->getASTContext().getTranslationUnitDecl();
61     for (auto *D : TU->decls()) {
62       // Don't re-import __va_list_tag, __builtin_va_list.
63       if (const auto *ND = dyn_cast<NamedDecl>(D))
64         if (IdentifierInfo *II = ND->getIdentifier())
65           if (II->isStr("__va_list_tag") || II->isStr("__builtin_va_list"))
66             continue;
67 
68       llvm::Expected<Decl *> ToDOrError = Importer.Import(D);
69 
70       if (ToDOrError) {
71         DeclGroupRef DGR(*ToDOrError);
72         CI.getASTConsumer().HandleTopLevelDecl(DGR);
73       } else {
74         llvm::consumeError(ToDOrError.takeError());
75       }
76     }
77   }
78 
79   AdaptedAction->ExecuteAction();
80   CI.getDiagnostics().getClient()->EndSourceFile();
81 }
82 
83 void ASTMergeAction::EndSourceFileAction() {
84   return AdaptedAction->EndSourceFileAction();
85 }
86 
87 ASTMergeAction::ASTMergeAction(std::unique_ptr<FrontendAction> adaptedAction,
88                                ArrayRef<std::string> ASTFiles)
89 : AdaptedAction(std::move(adaptedAction)), ASTFiles(ASTFiles.begin(), ASTFiles.end()) {
90   assert(AdaptedAction && "ASTMergeAction needs an action to adapt");
91 }
92 
93 ASTMergeAction::~ASTMergeAction() {
94 }
95 
96 bool ASTMergeAction::usesPreprocessorOnly() const {
97   return AdaptedAction->usesPreprocessorOnly();
98 }
99 
100 TranslationUnitKind ASTMergeAction::getTranslationUnitKind() {
101   return AdaptedAction->getTranslationUnitKind();
102 }
103 
104 bool ASTMergeAction::hasPCHSupport() const {
105   return AdaptedAction->hasPCHSupport();
106 }
107 
108 bool ASTMergeAction::hasASTFileSupport() const {
109   return AdaptedAction->hasASTFileSupport();
110 }
111 
112 bool ASTMergeAction::hasCodeCompletionSupport() const {
113   return AdaptedAction->hasCodeCompletionSupport();
114 }
115