Compilation cleanup

include/swift/AST/DiagnosticsDriver.def

@@ -113,6 +113,10 @@ WARNING(warn_cannot_stat_input,none,
         "unable to determine when '%0' was last modified: %1",
         (StringRef, StringRef))
 
+WARNING(warn_unable_to_load_dependencies, none,
+        "unable to load dependencies file \"%0\", disabling incremental mode",
+        (StringRef))
+
 ERROR(error_input_changed_during_build,none,
       "input file '%0' was modified during the build",
       (StringRef))

include/swift/Driver/Compilation.h

@@ -41,6 +41,7 @@ namespace swift {
 namespace driver {
   class Driver;
   class ToolChain;
+  class PerformJobsState;
 
 /// An enum providing different levels of output which should be produced
 /// by a Compilation.
@@ -56,6 +57,7 @@ enum class OutputLevel {
 };
 
 class Compilation {
+  friend class PerformJobsState;
 private:
   /// The DiagnosticEngine to which this Compilation should emit diagnostics.
   DiagnosticEngine &Diags;
@@ -136,6 +138,10 @@ class Compilation {
   /// rebuilt.
   bool ShowIncrementalBuildDecisions = false;
 
+  /// When true, traces the lifecycle of each driver job. Provides finer
+  /// detail than ShowIncrementalBuildDecisions.
+  bool ShowJobLifecycle = false;
+
   static const Job *unwrap(const std::unique_ptr<const Job> &p) {
     return p.get();
   }
@@ -194,6 +200,10 @@ class Compilation {
     ShowIncrementalBuildDecisions = value;
   }
 
+  void setShowJobLifecycle(bool value = true) {
+    ShowJobLifecycle = value;
+  }
+
   void setCompilationRecordPath(StringRef path) {
     assert(CompilationRecordPath.empty() && "already set");
     CompilationRecordPath = path;

include/swift/Driver/Job.h

@@ -168,6 +168,9 @@ class Job {
   /// terminating output with the given \p terminator.
   void printCommandLine(raw_ostream &Stream, StringRef Terminator = "\n") const;
 
+  /// Print a short summary of this Job to the given \p Stream.
+  void printSummary(raw_ostream &Stream) const;
+
   /// Print the command line for this Job to the given \p stream,
   /// and include any extra environment variables that will be set.
   ///

include/swift/Option/Options.td

@@ -91,6 +91,9 @@ def driver_use_frontend_path : Separate<["-"], "driver-use-frontend-path">,
 def driver_show_incremental : Flag<["-"], "driver-show-incremental">,
   InternalDebugOpt,
   HelpText<"With -v, dump information about why files are being rebuilt">;
+def driver_show_job_lifecycle : Flag<["-"], "driver-show-job-lifecycle">,
+  InternalDebugOpt,
+  HelpText<"Show every step in the lifecycle of driver jobs">;
 def driver_use_filelists : Flag<["-"], "driver-use-filelists">,
   InternalDebugOpt, HelpText<"Pass input files as filelists whenever possible">;