Remove incremental builds from the Legacy driver

The C++-based driver is deprecated and this will help reduce the code surface that requires maintenance as the legacy driver is fully sunset.

Author: artemcm

include/swift/AST/DiagnosticsDriver.def

@@ -188,6 +188,9 @@ WARNING(warn_drv_darwin_sdk_invalid_settings, none,
 WARNING(warning_unsupported_driver_option,none,
         "option '%0' is only supported in swift-driver", (StringRef))
 
+WARNING(new_driver_not_found,none,
+        "using (deprecated) legacy driver, Swift installation does not contain swift-driver at: '%0'", (StringRef))
+
 WARNING(old_driver_deprecated,none,
         "legacy driver is now deprecated; consider avoiding specifying '%0'", (StringRef))
 #define UNDEFINE_DIAGNOSTIC_MACROS

include/swift/Driver/Action.h

@@ -128,78 +128,16 @@ class JobAction : public Action {
   }
 };
 
-class IncrementalJobAction : public JobAction {
-public:
-  struct InputInfo {
-    /// The status of an input known to the driver. These are used to affect
-    /// the scheduling decisions made during an incremental build.
-    ///
-    /// \Note The order of cases matters. They are ordered from least to
-    /// greatest impact on the incremental build schedule.
-    enum class Status {
-      /// The input to this job is up to date.
-      UpToDate,
-      /// The input to this job has changed in a way that requires this job to
-      /// be rerun, but not in such a way that it requires a cascading rebuild.
-      NeedsNonCascadingBuild,
-      /// The input to this job has changed in a way that requires this job to
-      /// be rerun, and in such a way that all jobs dependent upon this one
-      /// must be scheduled as well.
-      NeedsCascadingBuild,
-      /// The input to this job was not known to the driver when it was last
-      /// run.
-      NewlyAdded
-    };
-
-  public:
-    Status status = Status::UpToDate;
-    llvm::sys::TimePoint<> previousModTime;
-
-    InputInfo() = default;
-    InputInfo(Status stat, llvm::sys::TimePoint<> time)
-        : status(stat), previousModTime(time) {}
-
-    static InputInfo makeNewlyAdded() {
-      return {Status::NewlyAdded, llvm::sys::TimePoint<>::max()};
-    }
-
-    static InputInfo makeNeedsCascadingRebuild() {
-      return {Status::NeedsCascadingBuild, llvm::sys::TimePoint<>::min()};
-    }
-  };
-
-private:
-  virtual void anchor() override;
-  InputInfo inputInfo;
-
-public:
-  IncrementalJobAction(Kind Kind, ArrayRef<const Action *> Inputs,
-                       file_types::ID Type, InputInfo info)
-      : JobAction(Kind, Inputs, Type), inputInfo(info) {}
-
-public:
-  InputInfo getInputInfo() const {
-    return inputInfo;
-  }
-
-public:
-  static bool classof(const Action *A) {
-    return A->getKind() == Action::Kind::CompileJob ||
-           A->getKind() == Action::Kind::MergeModuleJob;
-  }
-};
 
-class CompileJobAction : public IncrementalJobAction {
+class CompileJobAction : public JobAction {
 private:
   virtual void anchor() override;
 
 public:
   CompileJobAction(file_types::ID OutputType)
-      : IncrementalJobAction(Action::Kind::CompileJob, llvm::None, OutputType,
-                             {}) {}
-  CompileJobAction(Action *Input, file_types::ID OutputType, InputInfo info)
-      : IncrementalJobAction(Action::Kind::CompileJob, Input, OutputType,
-                             info) {}
+      : JobAction(Action::Kind::CompileJob, llvm::None, OutputType) {}
+  CompileJobAction(Action *Input, file_types::ID OutputType)
+      : JobAction(Action::Kind::CompileJob, Input, OutputType) {}
 
   static bool classof(const Action *A) {
     return A->getKind() == Action::Kind::CompileJob;
@@ -283,12 +221,12 @@ class REPLJobAction : public JobAction {
   }
 };
 
-class MergeModuleJobAction : public IncrementalJobAction {
+class MergeModuleJobAction : public JobAction {
   virtual void anchor() override;
 public:
-  MergeModuleJobAction(ArrayRef<const Action *> Inputs, InputInfo input)
-      : IncrementalJobAction(Action::Kind::MergeModuleJob, Inputs,
-                             file_types::TY_SwiftModuleFile, input) {}
+  MergeModuleJobAction(ArrayRef<const Action *> Inputs)
+      : JobAction(Action::Kind::MergeModuleJob, Inputs,
+                  file_types::TY_SwiftModuleFile) {}
 
   static bool classof(const Action *A) {
     return A->getKind() == Action::Kind::MergeModuleJob;

include/swift/Driver/Compilation.h

@@ -24,7 +24,6 @@
 #include "swift/Basic/OutputFileMap.h"
 #include "swift/Basic/Statistic.h"
 #include "swift/Driver/Driver.h"
-#include "swift/Driver/FineGrainedDependencyDriverGraph.h"
 #include "swift/Driver/Job.h"
 #include "swift/Driver/Util.h"
 #include "llvm/ADT/StringRef.h"
@@ -84,15 +83,9 @@ class Compilation {
     bool hadAbnormalExit;
     /// The exit code of this driver process.
     int exitCode;
-    /// The dependency graph built up during the compilation of this module.
-    ///
-    /// This data is used for cross-module module dependencies.
-    fine_grained_dependencies::ModuleDepGraph depGraph;
 
-    Result(bool hadAbnormalExit, int exitCode,
-           fine_grained_dependencies::ModuleDepGraph depGraph)
-        : hadAbnormalExit(hadAbnormalExit), exitCode(exitCode),
-          depGraph(std::move(depGraph)) {}
+    Result(bool hadAbnormalExit, int exitCode)
+        : hadAbnormalExit(hadAbnormalExit), exitCode(exitCode) {}
 
     Result(const Result &) = delete;
     Result &operator=(const Result &) = delete;
@@ -102,8 +95,7 @@ class Compilation {
 
     /// Construct a \c Compilation::Result from just an exit code.
     static Result code(int code) {
-      return Compilation::Result{false, code,
-                                 fine_grained_dependencies::ModuleDepGraph()};
+      return Compilation::Result{false, code};
     }
   };
 
@@ -171,33 +163,10 @@ class Compilation {
   /// These apply whether the compilation succeeds or fails. If the
   llvm::StringMap<PreserveOnSignal> TempFilePaths;
 
-  /// Write information about this compilation to this file.
-  ///
-  /// This is used for incremental builds.
-  std::string CompilationRecordPath;
-
-  /// A hash representing all the arguments that could trigger a full rebuild.
-  std::string ArgsHash;
-
-  /// When the build was started.
-  ///
-  /// This should be as close as possible to when the driver was invoked, since
-  /// it's used as a lower bound.
-  llvm::sys::TimePoint<> BuildStartTime;
-
-  /// The time of the last build.
-  ///
-  /// If unknown, this will be some time in the past.
-  llvm::sys::TimePoint<> LastBuildTime = llvm::sys::TimePoint<>::min();
-
   /// Indicates whether this Compilation should continue execution of subtasks
   /// even if they returned an error status.
   bool ContinueBuildingAfterErrors = false;
 
-  /// Indicates whether tasks should only be executed if their output is out
-  /// of date.
-  bool EnableIncrementalBuild;
-
   /// Indicates whether groups of parallel frontend jobs should be merged
   /// together and run in composite "batch jobs" when possible, to reduce
   /// redundant work.
@@ -256,17 +225,6 @@ class Compilation {
   /// -disable-only-one-dependency-file on the command line.
   const bool OnlyOneDependencyFile;
 
-private:
-  /// Helpful for debugging, but slows down the driver. So, only turn on when
-  /// needed.
-  const bool VerifyFineGrainedDependencyGraphAfterEveryImport;
-  /// Helpful for debugging, but slows down the driver. So, only turn on when
-  /// needed.
-  const bool EmitFineGrainedDependencyDotFileAfterEveryImport;
-
-  /// (experimental) Enable cross-module incremental build scheduling.
-  const bool EnableCrossModuleIncrementalBuild;
-
 private:
   template <typename T>
   static T *unwrap(const std::unique_ptr<T> &p) {
@@ -285,22 +243,15 @@ class Compilation {
               std::unique_ptr<llvm::opt::InputArgList> InputArgs,
               std::unique_ptr<llvm::opt::DerivedArgList> TranslatedArgs,
               InputFileList InputsWithTypes,
-              std::string CompilationRecordPath,
-              StringRef ArgsHash, llvm::sys::TimePoint<> StartTime,
-              llvm::sys::TimePoint<> LastBuildTime,
               size_t FilelistThreshold,
-              bool EnableIncrementalBuild = false,
               bool EnableBatchMode = false,
               unsigned BatchSeed = 0,
               llvm::Optional<unsigned> BatchCount = llvm::None,
               llvm::Optional<unsigned> BatchSizeLimit = llvm::None,
               bool SaveTemps = false,
               bool ShowDriverTimeCompilation = false,
               std::unique_ptr<UnifiedStatsReporter> Stats = nullptr,
-              bool OnlyOneDependencyFile = false,
-              bool VerifyFineGrainedDependencyGraphAfterEveryImport = false,
-              bool EmitFineGrainedDependencyDotFileAfterEveryImport = false,
-              bool EnableCrossModuleIncrementalBuild = false);
+              bool OnlyOneDependencyFile = false);
   // clang-format on
   ~Compilation();
 
@@ -353,19 +304,6 @@ class Compilation {
     return DerivedOutputFileMap;
   }
 
-  bool getIncrementalBuildEnabled() const {
-    return EnableIncrementalBuild;
-  }
-  void disableIncrementalBuild(Twine why);
-
-  bool getVerifyFineGrainedDependencyGraphAfterEveryImport() const {
-    return VerifyFineGrainedDependencyGraphAfterEveryImport;
-  }
-
-  bool getEmitFineGrainedDependencyDotFileAfterEveryImport() const {
-    return EmitFineGrainedDependencyDotFileAfterEveryImport;
-  }
-
   bool getBatchModeEnabled() const {
     return EnableBatchMode;
   }
@@ -377,13 +315,6 @@ class Compilation {
     ContinueBuildingAfterErrors = Value;
   }
 
-  bool getShowIncrementalBuildDecisions() const {
-    return ShowIncrementalBuildDecisions;
-  }
-  void setShowIncrementalBuildDecisions(bool value = true) {
-    ShowIncrementalBuildDecisions = value;
-  }
-
   bool getShowJobLifecycle() const {
     return ShowJobLifecycle;
   }
@@ -395,10 +326,6 @@ class Compilation {
     return ShowDriverTimeCompilation;
   }
 
-  bool getEnableCrossModuleIncrementalBuild() const {
-    return EnableCrossModuleIncrementalBuild;
-  }
-
   size_t getFilelistThreshold() const {
     return FilelistThreshold;
   }
@@ -420,7 +347,7 @@ class Compilation {
   /// True if extra work has to be done when tracing through the dependency
   /// graph, either in order to print dependencies or to collect statistics.
   bool getTraceDependencies() const {
-    return getShowIncrementalBuildDecisions() || getStatsReporter();
+    return getStatsReporter();
   }
 
   OutputLevel getOutputLevel() const {
@@ -431,12 +358,10 @@ class Compilation {
     return BatchSeed;
   }
 
-  llvm::sys::TimePoint<> getLastBuildTime() const {
-    return LastBuildTime;
+  llvm::Optional<unsigned> getBatchCount() const {
+    return BatchCount;
   }
 
-  llvm::Optional<unsigned> getBatchCount() const { return BatchCount; }
-
   llvm::Optional<unsigned> getBatchSizeLimit() const { return BatchSizeLimit; }
 
   /// Requests the path to a file containing all input source files. This can
@@ -448,17 +373,6 @@ class Compilation {
   /// \sa types::isPartOfSwiftCompilation
   const char *getAllSourcesPath() const;
 
-  /// Retrieve the path to the external swift deps file.
-  ///
-  /// For cross-module incremental builds, this file contains the dependencies
-  /// from all the modules integrated over the prior build.
-  ///
-  /// Currently this patch is relative to the build record, but we may want
-  /// to allow the output file map to customize this at some point.
-  std::string getExternalSwiftDepsFilePath() const {
-    return CompilationRecordPath + ".external";
-  }
-
   /// Asks the Compilation to perform the Jobs which it knows about.
   ///
   /// \param TQ The TaskQueue used to schedule jobs for execution.

include/swift/Driver/Driver.h

@@ -329,12 +329,9 @@ class Driver {
   /// \param[out] TopLevelActions The main Actions to build Jobs for.
   /// \param TC the default host tool chain.
   /// \param OI The OutputInfo for which Actions should be generated.
-  /// \param OutOfDateMap If present, information used to decide which files
-  /// need to be rebuilt.
   /// \param C The Compilation to which Actions should be added.
   void buildActions(SmallVectorImpl<const Action *> &TopLevelActions,
                     const ToolChain &TC, const OutputInfo &OI,
-                    const InputInfoMap *OutOfDateMap,
                     Compilation &C) const;
 
   /// Construct the OutputFileMap for the driver from the given arguments.