Merge branch 'master' into RemoveRedundantBufferZeroingNSStringAPI

Author: valeriyvan

README.md

@@ -8,6 +8,9 @@
 | **macOS**        | x86_64 |[![Build Status](https://ci.swift.org/job/oss-swift-incremental-RA-osx/lastCompletedBuild/badge/icon)](https://ci.swift.org/job/oss-swift-incremental-RA-osx)|[![Build Status](https://ci.swift.org/job/oss-swift-package-osx/lastCompletedBuild/badge/icon)](https://ci.swift.org/job/oss-swift-package-osx)|
 | **Ubuntu 16.04** | x86_64 | [![Build Status](https://ci.swift.org/job/oss-swift-incremental-RA-linux-ubuntu-16_04/lastCompletedBuild/badge/icon)](https://ci.swift.org/job/oss-swift-incremental-RA-linux-ubuntu-16_04)|[![Build Status](https://ci.swift.org/job/oss-swift-package-linux-ubuntu-16_04/lastCompletedBuild/badge/icon)](https://ci.swift.org/job/oss-swift-package-linux-ubuntu-16_04)|
 | **Ubuntu 18.04** | x86_64 | [![Build Status](https://ci.swift.org/job/oss-swift-incremental-RA-linux-ubuntu-18_04/lastCompletedBuild/badge/icon)](https://ci.swift.org/job/oss-swift-incremental-RA-linux-ubuntu-18_04)|[![Build Status](https://ci.swift.org/job/oss-swift-package-linux-ubuntu-18_04/lastCompletedBuild/badge/icon)](https://ci.swift.org/job/oss-swift-package-linux-ubuntu-18_04)|
+| **Ubuntu 20.04** | x86_64 | [![Build Status](https://ci.swift.org/job/oss-swift-package-ubuntu-20_04/lastCompletedBuild/badge/icon)](https://ci.swift.org/job/oss-swift-package-ubuntu-20_04)|[![Build Status](https://ci.swift.org/job/oss-swift-package-ubuntu-20_04/lastCompletedBuild/badge/icon)](https://ci.swift.org/job/oss-swift-package-ubuntu-20_04)|
+| **CentOS 8** | x86_64 | [![Build Status](https://ci.swift.org/job/oss-swift-package-centos-8/lastCompletedBuild/badge/icon)](https://ci.swift.org/job/oss-swift-package-centos-8)|[![Build Status](https://ci.swift.org/job/oss-swift-package-linux-ubuntu-18_04/lastCompletedBuild/badge/icon)](https://ci.swift.org/job/oss-swift-package-centos-8)|
+| **Amazon Linux 2** | x86_64 | [![Build Status](https://ci.swift.org/job/oss-swift-package-amazon-linux-2/lastCompletedBuild/badge/icon)](https://ci.swift.org/job/oss-swift-package-amazon-linux-2)|[![Build Status](https://ci.swift.org/job/oss-swift-package-amazon-linux-2/lastCompletedBuild/badge/icon)](https://ci.swift.org/job/oss-swift-package-amazon-linux-2)|
 
 **Swift Community-Hosted CI Platforms**
 

cmake/modules/AddSwift.cmake

@@ -348,13 +348,11 @@ function(_add_host_variant_link_flags target)
       ${CMAKE_BINARY_DIR}/winsdk_lib_${SWIFT_HOST_VARIANT_ARCH}_symlinks)
   elseif(SWIFT_HOST_VARIANT_SDK STREQUAL HAIKU)
     target_link_libraries(${target} PRIVATE
-      atomic
       bsd)
     target_link_options(${target} PRIVATE
       "SHELL:-Xlinker -Bsymbolic")
   elseif(SWIFT_HOST_VARIANT_SDK STREQUAL ANDROID)
     target_link_libraries(${target} PRIVATE
-      atomic
       dl
       log
       # We need to add the math library, which is linked implicitly by libc++

docs/ContinuousIntegration.md

@@ -92,6 +92,9 @@ macOS platform               | @swift-ci Please smoke benchmark              | S
 Linux platform               | @swift-ci Please test Linux platform          | Swift Test Linux Platform (smoke test)<br>Swift Test Linux Platform
 Linux platform               | @swift-ci Please clean test Linux platform    | Swift Test Linux Platform (smoke test)<br>Swift Test Linux Platform
 macOS platform               | @swift-ci Please ASAN test                    | Swift ASAN Test OS X Platform
+Ubuntu 20.04                | @swift-ci Please test Ubuntu 20.04 platform    | Swift Test Ubuntu 20.04 Platform
+CentOS 8                    | @swift-ci Please test CentOS 8 platform    | Swift Test CentOS 8 Platform
+Amazon Linux 2              | @swift-ci Please test Amazon Linux 2 platform    | Swift Test Amazon Linux 2 Platform
 
 The core principles of validation testing is that:
 

include/swift/AST/ASTContext.h

@@ -121,6 +121,7 @@ namespace swift {
   class UnifiedStatsReporter;
   class IndexSubset;
   struct SILAutoDiffDerivativeFunctionKey;
+  struct SubASTContextDelegate;
 
   enum class KnownProtocolKind : uint8_t;
 
@@ -719,7 +720,8 @@ class ASTContext final {
   Optional<ModuleDependencies> getModuleDependencies(
       StringRef moduleName,
       bool isUnderlyingClangModule,
-      ModuleDependenciesCache &cache);
+      ModuleDependenciesCache &cache,
+      SubASTContextDelegate &delegate);
 
   /// Load extensions to the given nominal type from the external
   /// module loaders.

include/swift/AST/DiagnosticsSema.def

@@ -3054,6 +3054,18 @@ ERROR(derivative_attr_original_already_has_derivative,none,
       "a derivative already exists for %0", (DeclName))
 NOTE(derivative_attr_duplicate_note,none,
      "other attribute declared here", ())
+ERROR(derivative_attr_access_level_mismatch,none,
+      "derivative function must have same access level as original function; "
+      "derivative function %2 is "
+      "%select{private|fileprivate|internal|public|open}3, "
+      "but original function %0 is "
+      "%select{private|fileprivate|internal|public|open}1",
+      (/*original*/ DeclName, /*original*/ AccessLevel,
+       /*derivative*/ DeclName, /*derivative*/ AccessLevel))
+NOTE(derivative_attr_fix_access,none,
+     "mark the derivative function as "
+     "'%select{private|fileprivate|internal|@usableFromInline|@usableFromInline}0' "
+     "to match the original function", (AccessLevel))
 
 // @transpose
 ERROR(transpose_attr_invalid_linearity_parameter_or_result,none,

include/swift/AST/Evaluator.h

@@ -245,7 +245,8 @@ class Evaluator {
   /// diagnostics through the given diagnostics engine.
   Evaluator(DiagnosticEngine &diags,
             bool debugDumpCycles,
-            bool buildDependencyGraph);
+            bool buildDependencyGraph,
+            bool enableExperimentalPrivateDeps);
 
   /// Emit GraphViz output visualizing the request graph.
   void emitRequestEvaluatorGraphViz(llvm::StringRef graphVizPath);

include/swift/AST/EvaluatorDependencies.h

@@ -113,7 +113,22 @@ struct DependencyCollector {
   llvm::SmallVector<evaluator::DependencySource, 8> dependencySources;
 
 public:
-  DependencyCollector() = default;
+  enum class Mode {
+    // Enables the current "status quo" behavior of the dependency collector.
+    //
+    // By default, the dependency collector moves to register dependencies in
+    // the referenced name trackers at the top of the active dependency stack.
+    StatusQuo,
+    // Enables an experimental mode to only register private dependencies.
+    //
+    // This mode restricts the dependency collector to ignore changes of
+    // scope. This has practical effect of charging all unqualified lookups to
+    // the primary file being acted upon instead of to the destination file.
+    ExperimentalPrivateDependencies,
+  };
+  Mode mode;
+
+  explicit DependencyCollector(Mode mode) : mode{mode} {};
 
 public:
   /// Registers a named reference from the current dependency scope to a member
@@ -206,19 +221,43 @@ struct DependencyCollector {
   };
 
 private:
+  /// Returns the first dependency source registered with the tracker, or
+  /// \c nullptr if no dependency sources have been registered.
+  SourceFile *getFirstDependencySourceOrNull() const {
+    if (dependencySources.empty())
+      return nullptr;
+    return dependencySources.front().getPointer();
+  }
+
   /// If there is an active dependency source, returns its
   /// \c ReferencedNameTracker. Else, returns \c nullptr.
   ReferencedNameTracker *getActiveDependencyTracker() const {
-    if (auto *source = getActiveDependencySourceOrNull())
-      return source->getRequestBasedReferencedNameTracker();
-    return nullptr;
+    SourceFile *source = nullptr;
+    switch (mode) {
+    case Mode::StatusQuo:
+      source = getActiveDependencySourceOrNull();
+      break;
+    case Mode::ExperimentalPrivateDependencies:
+      source = getFirstDependencySourceOrNull();
+      break;
+    }
+    
+    if (!source)
+      return nullptr;
+
+    return source->getRequestBasedReferencedNameTracker();
   }
 
   /// Returns \c true if the scope of the current active source cascades.
   ///
   /// If there is no active scope, the result always cascades.
   bool isActiveSourceCascading() const {
-    return getActiveSourceScope() == evaluator::DependencyScope::Cascading;
+    switch (mode) {
+    case Mode::StatusQuo:
+      return getActiveSourceScope() == evaluator::DependencyScope::Cascading;
+    case Mode::ExperimentalPrivateDependencies:
+      return false;
+    }
   }
 };
 } // end namespace evaluator

include/swift/AST/ModuleLoader.h

@@ -25,6 +25,7 @@
 #include "llvm/ADT/SmallSet.h"
 #include "llvm/ADT/StringSet.h"
 #include "llvm/ADT/TinyPtrVector.h"
+#include "swift/AST/ModuleDependencies.h"
 
 namespace llvm {
 class FileCollector;
@@ -84,6 +85,15 @@ class DependencyTracker {
   std::shared_ptr<clang::DependencyCollector> getClangCollector();
 };
 
+/// Abstract interface to run an action in a sub ASTContext.
+struct SubASTContextDelegate {
+  virtual bool runInSubContext(ASTContext &ctx, StringRef interfacePath,
+    llvm::function_ref<bool(ASTContext&)> action) {
+    llvm_unreachable("function should be overriden");
+  }
+  virtual ~SubASTContextDelegate() = default;
+};
+
 /// Abstract interface that loads named modules into the AST.
 class ModuleLoader {
   virtual void anchor();
@@ -186,7 +196,7 @@ class ModuleLoader {
   /// if no such module exists.
   virtual Optional<ModuleDependencies> getModuleDependencies(
       StringRef moduleName,
-      ModuleDependenciesCache &cache) = 0;
+      ModuleDependenciesCache &cache, SubASTContextDelegate &delegate) = 0;
 };
 
 } // namespace swift

include/swift/Basic/LangOptions.h

@@ -357,6 +357,10 @@ namespace swift {
     /// conformances.
     bool EnableExperimentalAdditiveArithmeticDerivedConformances = false;
 
+    /// Whether to enable a more aggressive mode of incremental dependency
+    /// gathering that never captures cascading edges.
+    bool EnableExperientalPrivateIntransitiveDependencies = false;
+
     /// Enable verification when every SubstitutionMap is constructed.
     bool VerifyAllSubstitutionMaps = false;
 

include/swift/ClangImporter/ClangImporter.h

@@ -370,7 +370,8 @@ class ClangImporter final : public ClangModuleLoader {
   void verifyAllModules() override;
 
   Optional<ModuleDependencies> getModuleDependencies(
-      StringRef moduleName, ModuleDependenciesCache &cache) override;
+      StringRef moduleName, ModuleDependenciesCache &cache,
+      SubASTContextDelegate &delegate) override;
 
   /// Add dependency information for the bridging header.
   ///