[clang] [APINotes] Upstream APINotesManager (PR #72389)

[Saleem Abdulrasool via cfe-commits]

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+//===--- APINotesManager.cpp - Manage API Notes Files ---------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/APINotes/APINotesManager.h"
+#include "clang/APINotes/APINotesReader.h"
+#include "clang/APINotes/APINotesYAMLCompiler.h"
+#include "clang/Basic/Diagnostic.h"
+#include "clang/Basic/FileManager.h"
+#include "clang/Basic/LangOptions.h"
+#include "clang/Basic/SourceManager.h"
+#include "clang/Basic/SourceMgrAdapter.h"
+#include "clang/Basic/Version.h"
+#include "llvm/ADT/APInt.h"
+#include "llvm/ADT/Hashing.h"
+#include "llvm/ADT/SetVector.h"
+#include "llvm/ADT/SmallPtrSet.h"
+#include "llvm/ADT/SmallVector.h"
+#include "llvm/ADT/Statistic.h"
+#include "llvm/Support/MemoryBuffer.h"
+#include "llvm/Support/Path.h"
+#include "llvm/Support/PrettyStackTrace.h"
+
+using namespace clang;
+using namespace api_notes;
+
+#define DEBUG_TYPE "API Notes"
+STATISTIC(NumHeaderAPINotes, "non-framework API notes files loaded");
+STATISTIC(NumPublicFrameworkAPINotes, "framework public API notes loaded");
+STATISTIC(NumPrivateFrameworkAPINotes, "framework private API notes loaded");
+STATISTIC(NumFrameworksSearched, "frameworks searched");
+STATISTIC(NumDirectoriesSearched, "header directories searched");
+STATISTIC(NumDirectoryCacheHits, "directory cache hits");
+
+namespace {
+/// Prints two successive strings, which much be kept alive as long as the
+/// PrettyStackTrace entry.
+class PrettyStackTraceDoubleString : public llvm::PrettyStackTraceEntry {
+  StringRef First, Second;
+
+public:
+  PrettyStackTraceDoubleString(StringRef First, StringRef Second)
+      : First(First), Second(Second) {}
+  void print(raw_ostream &OS) const override { OS << First << Second; }
+};
+} // namespace
+
+APINotesManager::APINotesManager(SourceManager &SM, const LangOptions &LangOpts)
+    : SM(SM), ImplicitAPINotes(LangOpts.APINotes) {}
+
+APINotesManager::~APINotesManager() {
+  // Free the API notes readers.
+  for (const auto &Entry : Readers) {
+    if (auto Reader = Entry.second.dyn_cast<APINotesReader *>())
+      delete Reader;
+  }
+
+  delete CurrentModuleReaders[0];
+  delete CurrentModuleReaders[1];
+}
+
+std::unique_ptr<APINotesReader>
+APINotesManager::loadAPINotes(FileEntryRef APINotesFile) {
+  PrettyStackTraceDoubleString Trace("Loading API notes from ",
+                                     APINotesFile.getName());
+
+  // Open the source file.
+  auto SourceFileID = SM.getOrCreateFileID(APINotesFile, SrcMgr::C_User);
+  auto SourceBuffer = SM.getBufferOrNone(SourceFileID, SourceLocation());
+  if (!SourceBuffer)
+    return nullptr;
+
+  // Compile the API notes source into a buffer.
+  // FIXME: Either propagate OSType through or, better yet, improve the binary
+  // APINotes format to maintain complete availability information.
+  // FIXME: We don't even really need to go through the binary format at all;
+  // we're just going to immediately deserialize it again.
+  llvm::SmallVector<char, 1024> APINotesBuffer;
+  std::unique_ptr<llvm::MemoryBuffer> CompiledBuffer;
+  {
+    SourceMgrAdapter SMAdapter(
+        SM, SM.getDiagnostics(), diag::err_apinotes_message,
+        diag::warn_apinotes_message, diag::note_apinotes_message, APINotesFile);
+    llvm::raw_svector_ostream OS(APINotesBuffer);
+    if (api_notes::compileAPINotes(
+            SourceBuffer->getBuffer(), SM.getFileEntryForID(SourceFileID), OS,
+            SMAdapter.getDiagHandler(), SMAdapter.getDiagContext()))
+      return nullptr;
+
+    // Make a copy of the compiled form into the buffer.
+    CompiledBuffer = llvm::MemoryBuffer::getMemBufferCopy(
+        StringRef(APINotesBuffer.data(), APINotesBuffer.size()));
+  }
+
+  // Load the binary form we just compiled.
+  auto Reader = APINotesReader::Create(std::move(CompiledBuffer), SwiftVersion);
+  assert(Reader && "Could not load the API notes we just generated?");
+  return Reader;
+}
+
+std::unique_ptr<APINotesReader>
+APINotesManager::loadAPINotes(StringRef Buffer) {
+  llvm::SmallVector<char, 1024> APINotesBuffer;
+  std::unique_ptr<llvm::MemoryBuffer> CompiledBuffer;
+  SourceMgrAdapter SMAdapter(
+      SM, SM.getDiagnostics(), diag::err_apinotes_message,
+      diag::warn_apinotes_message, diag::note_apinotes_message, std::nullopt);
+  llvm::raw_svector_ostream OS(APINotesBuffer);
+
+  if (api_notes::compileAPINotes(Buffer, nullptr, OS,
+                                 SMAdapter.getDiagHandler(),
+                                 SMAdapter.getDiagContext()))
+    return nullptr;
+
+  CompiledBuffer = llvm::MemoryBuffer::getMemBufferCopy(
+      StringRef(APINotesBuffer.data(), APINotesBuffer.size()));
+  auto Reader = APINotesReader::Create(std::move(CompiledBuffer), SwiftVersion);
+  assert(Reader && "Could not load the API notes we just generated?");
+  return Reader;
+}
+
+bool APINotesManager::loadAPINotes(const DirectoryEntry *HeaderDir,
+                                   FileEntryRef APINotesFile) {
+  assert(Readers.find(HeaderDir) == Readers.end());
+  if (auto Reader = loadAPINotes(APINotesFile)) {
+    Readers[HeaderDir] = Reader.release();
+    return false;
+  }
+
+  Readers[HeaderDir] = nullptr;
+  return true;
+}
+
+OptionalFileEntryRef
+APINotesManager::findAPINotesFile(DirectoryEntryRef Directory,
+                                  StringRef Basename, bool WantPublic) {
+  FileManager &FM = SM.getFileManager();
+
+  llvm::SmallString<128> Path(Directory.getName());
+
+  StringRef BasenameSuffix = "";
+  if (!WantPublic)
+    BasenameSuffix = "_private";
+
+  // Look for the source API notes file.
+  llvm::sys::path::append(Path, llvm::Twine(Basename) + BasenameSuffix + "." +
+                                    SOURCE_APINOTES_EXTENSION);
+  return FM.getOptionalFileRef(Path, /*Open*/ true);
+}
+
+OptionalDirectoryEntryRef APINotesManager::loadFrameworkAPINotes(
+    llvm::StringRef FrameworkPath, llvm::StringRef FrameworkName, bool Public) {
+  FileManager &FM = SM.getFileManager();
+
+  llvm::SmallString<128> Path(FrameworkPath);
+  unsigned FrameworkNameLength = Path.size();
+
+  // Form the path to the APINotes file.
+  llvm::sys::path::append(Path, "APINotes");
+  if (Public)
+    llvm::sys::path::append(
+        Path, (llvm::Twine(FrameworkName) + "." + SOURCE_APINOTES_EXTENSION));
+  else
+    llvm::sys::path::append(Path, (llvm::Twine(FrameworkName) + "_private." +
+                                   SOURCE_APINOTES_EXTENSION));
+
+  // Try to open the APINotes file.
+  auto APINotesFile = FM.getOptionalFileRef(Path);
+  if (!APINotesFile)
+    return std::nullopt;
+
+  // Form the path to the corresponding header directory.
+  Path.resize(FrameworkNameLength);
+  if (Public)
+    llvm::sys::path::append(Path, "Headers");
+  else
+    llvm::sys::path::append(Path, "PrivateHeaders");
----------------
compnerd wrote:

I would just use a ternary and collapse this.

https://github.com/llvm/llvm-project/pull/72389