Merge pull request #40379 from apple/revert-40368-revert-40357-obfuscate-searialized-paths

Re-apply "serialization: obfuscate the serialized search paths"

Author: nkcsgexi

include/swift/AST/FileUnit.h

@@ -405,6 +405,8 @@ class LoadedFile : public FileUnit {
   virtual void collectBasicSourceFileInfo(
       llvm::function_ref<void(const BasicSourceFileInfo &)> callback) const {}
 
+  virtual void collectSerializedSearchPath(
+      llvm::function_ref<void(StringRef)> callback) const {}
   static bool classof(const FileUnit *file) {
     return file->getKind() == FileUnitKind::SerializedAST ||
            file->getKind() == FileUnitKind::ClangModule ||

include/swift/AST/Module.h

@@ -833,6 +833,8 @@ class ModuleDecl
   void collectBasicSourceFileInfo(
       llvm::function_ref<void(const BasicSourceFileInfo &)> callback) const;
 
+  void collectSerializedSearchPath(
+      llvm::function_ref<void(StringRef)> callback) const;
   /// Retrieve a fingerprint value that summarizes the contents of this module.
   ///
   /// This interface hash a of a module is guaranteed to change if the interface

include/swift/AST/SearchPathOptions.h

@@ -103,6 +103,10 @@ class SearchPathOptions {
   /// specified in LLDB from the target.source-map entries.
   PathRemapper SearchPathRemapper;
 
+  /// Recover the search paths deserialized from .swiftmodule files to their
+  /// original form.
+  PathObfuscator DeserializedPathRecoverer;
+
 private:
   static StringRef
   pathStringFromFrameworkSearchPath(const FrameworkSearchPath &next) {

include/swift/Basic/PathRemapper.h

@@ -58,6 +58,21 @@ class PathRemapper {
   }
 };
 
+class PathObfuscator {
+  PathRemapper obfuscator, recoverer;
+public:
+  void addMapping(StringRef FromPrefix, StringRef ToPrefix) {
+    obfuscator.addMapping(FromPrefix, ToPrefix);
+    recoverer.addMapping(ToPrefix, FromPrefix);
+  }
+  std::string obfuscate(StringRef Path) const {
+    return obfuscator.remapPath(Path);
+  }
+  std::string recover(StringRef Path) const {
+    return recoverer.remapPath(Path);
+  }
+};
+
 } // end namespace swift
 
 #endif // SWIFT_BASIC_PATHREMAPPER_H

include/swift/Frontend/FrontendOptions.h

@@ -15,6 +15,7 @@
 
 #include "swift/Basic/FileTypes.h"
 #include "swift/Basic/Version.h"
+#include "swift/Basic/PathRemapper.h"
 #include "swift/Frontend/FrontendInputsAndOutputs.h"
 #include "swift/Frontend/InputFile.h"
 #include "llvm/ADT/Hashing.h"
@@ -437,6 +438,10 @@ class FrontendOptions {
   /// Whether to include symbols with SPI information in the symbol graph.
   bool IncludeSPISymbolsInSymbolGraph = false;
 
+  /// This is used to obfuscate the serialized search paths so we don't have
+  /// to encode the actual paths into the .swiftmodule file.
+  PathObfuscator serializedPathObfuscator;
+
 private:
   static bool canActionEmitDependencies(ActionType);
   static bool canActionEmitReferenceDependencies(ActionType);

include/swift/Option/FrontendOptions.td

@@ -165,6 +165,10 @@ def print_clang_stats : Flag<["-"], "print-clang-stats">,
 
 def serialize_debugging_options : Flag<["-"], "serialize-debugging-options">,
   HelpText<"Always serialize options for debugging (default: only for apps)">;
+
+def serialized_path_obfuscate : Separate<["-"], "serialized-path-obfuscate">,
+    HelpText<"Remap source paths in debug info">, MetaVarName<"<prefix=replacement>">;
+
 def no_serialize_debugging_options :
   Flag<["-"], "no-serialize-debugging-options">,
   HelpText<"Never serialize options for debugging (default: only for apps)">;

include/swift/Serialization/SerializationOptions.h

@@ -45,6 +45,10 @@ namespace swift {
     /// Path prefixes that should be rewritten in debug info.
     PathRemapper DebuggingOptionsPrefixMap;
 
+    /// Obfuscate the serialized paths so we don't have the actual paths encoded
+    /// in the .swiftmodule file.
+    PathObfuscator PathObfuscator;
+
     /// Describes a single-file dependency for this module, along with the
     /// appropriate strategy for how to verify if it's up-to-date.
     class FileDependency {

include/swift/Serialization/SerializedModuleLoader.h

@@ -465,6 +465,9 @@ class SerializedASTFile final : public LoadedFile {
   virtual void collectBasicSourceFileInfo(
       llvm::function_ref<void(const BasicSourceFileInfo &)>) const override;
 
+  virtual void collectSerializedSearchPath(
+      llvm::function_ref<void(StringRef)> callback) const override;
+
   static bool classof(const FileUnit *file) {
     return file->getKind() == FileUnitKind::SerializedAST;
   }

include/swift/Serialization/Validation.h

@@ -104,7 +104,7 @@ struct ValidationInfo {
 /// \sa validateSerializedAST()
 class ExtendedValidationInfo {
   SmallVector<StringRef, 4> ExtraClangImporterOpts;
-  StringRef SDKPath;
+  std::string SDKPath;
   StringRef ModuleABIName;
   struct {
     unsigned ArePrivateImportsEnabled : 1;
@@ -121,7 +121,7 @@ class ExtendedValidationInfo {
   ExtendedValidationInfo() : Bits() {}
 
   StringRef getSDKPath() const { return SDKPath; }
-  void setSDKPath(StringRef path) {
+  void setSDKPath(std::string path) {
     assert(SDKPath.empty());
     SDKPath = path;
   }

lib/AST/Module.cpp

@@ -1808,6 +1808,15 @@ void ModuleDecl::collectBasicSourceFileInfo(
   }
 }
 
+void ModuleDecl::collectSerializedSearchPath(
+    llvm::function_ref<void(StringRef)> callback) const {
+  for (const FileUnit *fileUnit : getFiles()) {
+    if (auto *serialized = dyn_cast<LoadedFile>(fileUnit)) {
+      serialized->collectSerializedSearchPath(callback);
+    }
+  }
+}
+
 Fingerprint ModuleDecl::getFingerprint() const {
   StableHasher hasher = StableHasher::defaultHasher();
   SmallVector<Fingerprint, 16> FPs;