1 //===--- Compiler.cpp --------------------------------------------*- 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 
9 #include "Compiler.h"
10 #include "support/Logger.h"
11 #include "clang/Basic/TargetInfo.h"
12 #include "clang/Lex/PreprocessorOptions.h"
13 #include "clang/Serialization/PCHContainerOperations.h"
14 #include "llvm/Support/Format.h"
15 #include "llvm/Support/FormatVariadic.h"
16 
17 namespace clang {
18 namespace clangd {
19 
20 void IgnoreDiagnostics::log(DiagnosticsEngine::Level DiagLevel,
21                             const clang::Diagnostic &Info) {
22   // FIXME: format lazily, in case vlog is off.
23   llvm::SmallString<64> Message;
24   Info.FormatDiagnostic(Message);
25 
26   llvm::SmallString<64> Location;
27   if (Info.hasSourceManager() && Info.getLocation().isValid()) {
28     auto &SourceMgr = Info.getSourceManager();
29     auto Loc = SourceMgr.getFileLoc(Info.getLocation());
30     llvm::raw_svector_ostream OS(Location);
31     Loc.print(OS, SourceMgr);
32     OS << ":";
33   }
34 
35   clangd::vlog("Ignored diagnostic. {0}{1}", Location, Message);
36 }
37 
38 void IgnoreDiagnostics::HandleDiagnostic(DiagnosticsEngine::Level DiagLevel,
39                                          const clang::Diagnostic &Info) {
40   IgnoreDiagnostics::log(DiagLevel, Info);
41 }
42 
43 std::unique_ptr<CompilerInvocation>
44 buildCompilerInvocation(const ParseInputs &Inputs, clang::DiagnosticConsumer &D,
45                         std::vector<std::string> *CC1Args) {
46   std::vector<const char *> ArgStrs;
47   for (const auto &S : Inputs.CompileCommand.CommandLine)
48     ArgStrs.push_back(S.c_str());
49 
50   if (Inputs.FS->setCurrentWorkingDirectory(Inputs.CompileCommand.Directory)) {
51     log("Couldn't set working directory when creating compiler invocation.");
52     // We proceed anyway, our lit-tests rely on results for non-existing working
53     // dirs.
54   }
55 
56   llvm::IntrusiveRefCntPtr<DiagnosticsEngine> CommandLineDiagsEngine =
57       CompilerInstance::createDiagnostics(new DiagnosticOptions, &D, false);
58   std::unique_ptr<CompilerInvocation> CI = createInvocationFromCommandLine(
59       ArgStrs, CommandLineDiagsEngine, Inputs.FS,
60       /*ShouldRecoverOnErrors=*/true, CC1Args);
61   if (!CI)
62     return nullptr;
63   // createInvocationFromCommandLine sets DisableFree.
64   CI->getFrontendOpts().DisableFree = false;
65   CI->getLangOpts()->CommentOpts.ParseAllComments = true;
66   CI->getLangOpts()->RetainCommentsFromSystemHeaders = true;
67 
68   // Disable any dependency outputting, we don't want to generate files or write
69   // to stdout/stderr.
70   CI->getDependencyOutputOpts().ShowIncludesDest =
71       ShowIncludesDestination::None;
72   CI->getDependencyOutputOpts().OutputFile.clear();
73   CI->getDependencyOutputOpts().HeaderIncludeOutputFile.clear();
74   CI->getDependencyOutputOpts().DOTOutputFile.clear();
75   CI->getDependencyOutputOpts().ModuleDependencyOutputDir.clear();
76 
77   // Disable any pch generation/usage operations. Since serialized preamble
78   // format is unstable, using an incompatible one might result in unexpected
79   // behaviours, including crashes.
80   CI->getPreprocessorOpts().ImplicitPCHInclude.clear();
81   CI->getPreprocessorOpts().PrecompiledPreambleBytes = {0, false};
82   CI->getPreprocessorOpts().PCHThroughHeader.clear();
83   CI->getPreprocessorOpts().PCHWithHdrStop = false;
84   CI->getPreprocessorOpts().PCHWithHdrStopCreate = false;
85 
86   // Recovery expression currently only works for C++.
87   if (CI->getLangOpts()->CPlusPlus) {
88     CI->getLangOpts()->RecoveryAST = Inputs.Opts.BuildRecoveryAST;
89     CI->getLangOpts()->RecoveryASTType = Inputs.Opts.PreserveRecoveryASTType;
90   }
91   return CI;
92 }
93 
94 std::unique_ptr<CompilerInstance>
95 prepareCompilerInstance(std::unique_ptr<clang::CompilerInvocation> CI,
96                         const PrecompiledPreamble *Preamble,
97                         std::unique_ptr<llvm::MemoryBuffer> Buffer,
98                         llvm::IntrusiveRefCntPtr<llvm::vfs::FileSystem> VFS,
99                         DiagnosticConsumer &DiagsClient) {
100   assert(VFS && "VFS is null");
101   assert(!CI->getPreprocessorOpts().RetainRemappedFileBuffers &&
102          "Setting RetainRemappedFileBuffers to true will cause a memory leak "
103          "of ContentsBuffer");
104 
105   // NOTE: we use Buffer.get() when adding remapped files, so we have to make
106   // sure it will be released if no error is emitted.
107   if (Preamble) {
108     Preamble->OverridePreamble(*CI, VFS, Buffer.get());
109   } else {
110     CI->getPreprocessorOpts().addRemappedFile(
111         CI->getFrontendOpts().Inputs[0].getFile(), Buffer.get());
112   }
113 
114   auto Clang = std::make_unique<CompilerInstance>(
115       std::make_shared<PCHContainerOperations>());
116   Clang->setInvocation(std::move(CI));
117   Clang->createDiagnostics(&DiagsClient, false);
118 
119   if (auto VFSWithRemapping = createVFSFromCompilerInvocation(
120           Clang->getInvocation(), Clang->getDiagnostics(), VFS))
121     VFS = VFSWithRemapping;
122   Clang->createFileManager(VFS);
123 
124   Clang->setTarget(TargetInfo::CreateTargetInfo(
125       Clang->getDiagnostics(), Clang->getInvocation().TargetOpts));
126   if (!Clang->hasTarget())
127     return nullptr;
128 
129   // RemappedFileBuffers will handle the lifetime of the Buffer pointer,
130   // release it.
131   Buffer.release();
132   return Clang;
133 }
134 
135 } // namespace clangd
136 } // namespace clang
137