[CodeCompletion] Lazily populate 'BasicSourceFileInfo'

Author: rintaro

include/swift/AST/RawComment.h

@@ -96,15 +96,51 @@ struct BasicDeclLocs {
   LineColumn EndLoc;
 };
 
-struct BasicSourceFileInfo {
+class BasicSourceFileInfo {
+  /// If this is non-null, fields other than 'FilePath' hasn't been populated.
+  /// The 'getInt()' part indicates this instance is constructed with a
+  /// SourceFile.
+  llvm::PointerIntPair<const SourceFile *, 1, bool> SFAndIsFromSF;
+
   StringRef FilePath;
-  Fingerprint InterfaceHash = Fingerprint::ZERO();
+  Fingerprint InterfaceHashIncludingTypeMembers = Fingerprint::ZERO();
   llvm::sys::TimePoint<> LastModified = {};
   uint64_t FileSize = 0;
 
-  BasicSourceFileInfo() {}
+  // Populate the from 'SF' member if exist. 'SF' will be cleared.
+  void populateWithSourceFileIfNeeded();
+
+public:
+  BasicSourceFileInfo(StringRef FilePath,
+                      Fingerprint InterfaceHashIncludingTypeMembers,
+                      llvm::sys::TimePoint<> LastModified, uint64_t FileSize)
+      : FilePath(FilePath),
+        InterfaceHashIncludingTypeMembers(InterfaceHashIncludingTypeMembers),
+        LastModified(LastModified), FileSize(FileSize) {}
+
+  ///  Construct with a 'SourceFile'. 'getInterfaceHashIncludingTypeMembers()',
+  ///  'getLastModified()' and 'getFileSize()' are laizily pupulated when
+  ///  accessed.
+  BasicSourceFileInfo(const SourceFile *SF);
+
+  bool isFromSourceFile() const;
+
+  StringRef getFilePath() const { return FilePath; }
 
-  bool populate(const SourceFile *SF);
+  Fingerprint getInterfaceHashIncludingTypeMembers() const {
+    const_cast<BasicSourceFileInfo *>(this)->populateWithSourceFileIfNeeded();
+    return InterfaceHashIncludingTypeMembers;
+  }
+
+  llvm::sys::TimePoint<> getLastModified() const {
+    const_cast<BasicSourceFileInfo *>(this)->populateWithSourceFileIfNeeded();
+    return LastModified;
+  }
+
+  uint64_t getFileSize() const {
+    const_cast<BasicSourceFileInfo *>(this)->populateWithSourceFileIfNeeded();
+    return FileSize;
+  }
 };
 
 } // namespace swift

lib/AST/Module.cpp

@@ -1539,10 +1539,7 @@ void ModuleDecl::collectBasicSourceFileInfo(
     llvm::function_ref<void(const BasicSourceFileInfo &)> callback) const {
   for (const FileUnit *fileUnit : getFiles()) {
     if (const auto *SF = dyn_cast<SourceFile>(fileUnit)) {
-      BasicSourceFileInfo info;
-      if (info.populate(SF))
-        continue;
-      callback(info);
+      callback(BasicSourceFileInfo(SF));
     } else if (auto *serialized = dyn_cast<LoadedFile>(fileUnit)) {
       serialized->collectBasicSourceFileInfo(callback);
     }
@@ -1553,7 +1550,7 @@ Fingerprint ModuleDecl::getFingerprint() const {
   StableHasher hasher = StableHasher::defaultHasher();
   SmallVector<Fingerprint, 16> FPs;
   collectBasicSourceFileInfo([&](const BasicSourceFileInfo &bsfi) {
-    FPs.emplace_back(bsfi.InterfaceHash);
+    FPs.emplace_back(bsfi.getInterfaceHashIncludingTypeMembers());
   });
 
   // Sort the fingerprints lexicographically so we have a stable hash despite

lib/AST/RawComment.cpp

@@ -24,6 +24,7 @@
 #include "swift/AST/PrettyStackTrace.h"
 #include "swift/AST/SourceFile.h"
 #include "swift/AST/Types.h"
+#include "swift/Basic/Defer.h"
 #include "swift/Basic/PrimitiveParsing.h"
 #include "swift/Basic/SourceManager.h"
 #include "swift/Markup/Markup.h"
@@ -247,26 +248,40 @@ CharSourceRange RawComment::getCharSourceRange() {
   return CharSourceRange(Start, Length);
 }
 
-bool BasicSourceFileInfo::populate(const SourceFile *SF) {
+BasicSourceFileInfo::BasicSourceFileInfo(const SourceFile *SF)
+    : SFAndIsFromSF(SF, true) {
+  FilePath = SF->getFilename();
+}
+
+bool BasicSourceFileInfo::isFromSourceFile() const {
+  return SFAndIsFromSF.getInt();
+}
+
+void BasicSourceFileInfo::populateWithSourceFileIfNeeded() {
+  const auto *SF = SFAndIsFromSF.getPointer();
+  if (!SF)
+    return;
+  SWIFT_DEFER {
+    SFAndIsFromSF.setPointer(nullptr);
+  };
+
   SourceManager &SM = SF->getASTContext().SourceMgr;
 
-  auto filename = SF->getFilename();
-  if (filename.empty())
-    return true;
-  auto stat = SM.getFileSystem()->status(filename);
+  if (FilePath.empty())
+    return;
+  auto stat = SM.getFileSystem()->status(FilePath);
   if (!stat)
-    return true;
+    return;
 
-  FilePath = filename;
   LastModified = stat->getLastModificationTime();
   FileSize = stat->getSize();
 
   if (SF->hasInterfaceHash()) {
-    InterfaceHash = SF->getInterfaceHashIncludingTypeMembers();
+    InterfaceHashIncludingTypeMembers = SF->getInterfaceHashIncludingTypeMembers();
   } else {
     // FIXME: Parse the file with EnableInterfaceHash option.
-    InterfaceHash = Fingerprint::ZERO();
+    InterfaceHashIncludingTypeMembers = Fingerprint::ZERO();
   }
 
-  return false;
+  return;
 }

lib/Serialization/ModuleFile.cpp

@@ -992,18 +992,13 @@ void ModuleFile::collectBasicSourceFileInfo(
     size_t terminatorOffset = filePath.find('\0');
     filePath = filePath.slice(0, terminatorOffset);
 
-    BasicSourceFileInfo info;
-    info.FilePath = filePath;
-    if (auto fingerprint = Fingerprint::fromString(fpStr))
-      info.InterfaceHash = fingerprint.getValue();
-    else {
+    auto fingerprint = Fingerprint::fromString(fpStr);
+    if (!fingerprint) {
       llvm::errs() << "Unconvertable fingerprint '" << fpStr << "'\n";
       abort();
     }
-    info.LastModified =
-        llvm::sys::TimePoint<>(std::chrono::nanoseconds(timestamp));
-    info.FileSize = fileSize;
-    callback(info);
+
+    callback(BasicSourceFileInfo(filePath, fingerprint.getValue(), llvm::sys::TimePoint<>(std::chrono::nanoseconds(timestamp)), fileSize));
   }
 }
 

lib/Serialization/SerializeDoc.cpp

@@ -794,18 +794,20 @@ static void emitFileListRecord(llvm::BitstreamWriter &Out,
     llvm::StringSet<> seenFilenames;
 
     void emitSourceFileInfo(const BasicSourceFileInfo &info) {
+      if (info.getFilePath().empty())
+        return;
       // Make 'FilePath' absolute for serialization;
-      SmallString<128> absolutePath = info.FilePath;
+      SmallString<128> absolutePath = info.getFilePath();
       llvm::sys::fs::make_absolute(absolutePath);
 
       // Don't emit duplicated files.
-      if (!seenFilenames.insert(info.FilePath).second)
+      if (!seenFilenames.insert(absolutePath).second)
         return;
 
       auto fileID = FWriter.getTextOffset(absolutePath);
-      auto fingerprintStr = info.InterfaceHash.getRawValue();
+      auto fingerprintStr = info.getInterfaceHashIncludingTypeMembers().getRawValue();
       auto timestamp = std::chrono::duration_cast<std::chrono::nanoseconds>(
-                           info.LastModified.time_since_epoch())
+                           info.getLastModified().time_since_epoch())
                            .count();
 
       llvm::raw_svector_ostream out(Buffer);
@@ -818,7 +820,7 @@ static void emitFileListRecord(llvm::BitstreamWriter &Out,
       // LastModified (nanoseconds since epoch).
       writer.write<uint64_t>(timestamp);
       // FileSize (num of bytes).
-      writer.write<uint64_t>(info.FileSize);
+      writer.write<uint64_t>(info.getFileSize());
     }
 
     SourceFileListWriter(StringWriter &FWriter) : FWriter(FWriter) {
@@ -827,10 +829,7 @@ static void emitFileListRecord(llvm::BitstreamWriter &Out,
   } writer(FWriter);
 
   if (SourceFile *SF = MSF.dyn_cast<SourceFile *>()) {
-    BasicSourceFileInfo info;
-    if (info.populate(SF))
-      return;
-    writer.emitSourceFileInfo(info);
+    writer.emitSourceFileInfo(BasicSourceFileInfo(SF));
   } else {
     auto *M = MSF.get<ModuleDecl *>();
     M->collectBasicSourceFileInfo([&](const BasicSourceFileInfo &info) {

tools/swift-ide-test/swift-ide-test.cpp

@@ -2517,10 +2517,10 @@ static void printModuleMetadata(ModuleDecl *MD) {
        << ", force load: " << (lib.shouldForceLoad() ? "true" : "false") << "\n";
   });
   MD->collectBasicSourceFileInfo([&](const BasicSourceFileInfo &info) {
-    OS << "filepath=" << info.FilePath << "; ";
-    OS << "hash=" << info.InterfaceHash.getRawValue() << "; ";
-    OS << "mtime=" << info.LastModified << "; ";
-    OS << "size=" << info.FileSize;
+    OS << "filepath=" << info.getFilePath() << "; ";
+    OS << "hash=" << info.getInterfaceHashIncludingTypeMembers().getRawValue() << "; ";
+    OS << "mtime=" << info.getLastModified() << "; ";
+    OS << "size=" << info.getFileSize();
     OS << "\n";
   });
 }