[Driver] Put new job-lifecycle diagnostic chatter behind another option.

Author: graydon

include/swift/Driver/Compilation.h

@@ -138,6 +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();
   }
@@ -196,6 +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/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">;
 

lib/Driver/Compilation.cpp

@@ -191,15 +191,15 @@ namespace driver {
     /// its inputs are in FinishedCommands.
     void scheduleCommandIfNecessaryAndPossible(const Job *Cmd) {
       if (ScheduledCommands.count(Cmd)) {
-        if (Comp.ShowIncrementalBuildDecisions) {
+        if (Comp.ShowJobLifecycle) {
           llvm::outs() << "Already scheduled: " << LogJob(Cmd) << "\n";
         }
         return;
       }
 
       if (auto Blocking = findUnfinishedJob(Cmd->getInputs())) {
         BlockingCommands[Blocking].push_back(Cmd);
-        if (Comp.ShowIncrementalBuildDecisions) {
+        if (Comp.ShowJobLifecycle) {
           llvm::outs() << "Blocked by: " << LogJob(Blocking)
                        << ", now blocking jobs: "
                        << LogJobArray(BlockingCommands[Blocking]) << "\n";
@@ -215,15 +215,15 @@ namespace driver {
       assert(Cmd->getExtraEnvironment().empty() &&
              "not implemented for compilations with multiple jobs");
       ScheduledCommands.insert(Cmd);
-      if (Comp.ShowIncrementalBuildDecisions)
+      if (Comp.ShowJobLifecycle)
         llvm::outs() << "Added to TaskQueue: " << LogJob(Cmd) << "\n";
       TQ->addTask(Cmd->getExecutable(), Cmd->getArguments(), llvm::None,
                   (void *)Cmd);
     }
 
     /// When a task finishes, check other Jobs that may be blocked.
     void markFinished(const Job *Cmd, bool Skipped=false) {
-      if (Comp.ShowIncrementalBuildDecisions) {
+      if (Comp.ShowJobLifecycle) {
         llvm::outs() << "Job "
                      << (Skipped ? "skipped" : "finished")
                      << ": " << LogJob(Cmd) << "\n";
@@ -233,7 +233,7 @@ namespace driver {
       auto BlockedIter = BlockingCommands.find(Cmd);
       if (BlockedIter != BlockingCommands.end()) {
         auto AllBlocked = std::move(BlockedIter->second);
-        if (Comp.ShowIncrementalBuildDecisions) {
+        if (Comp.ShowJobLifecycle) {
           llvm::outs() << "Scheduling maybe-unblocked jobs: "
                        << LogJobArray(AllBlocked) << "\n";
         }

lib/Driver/Driver.cpp

@@ -470,6 +470,8 @@ std::unique_ptr<Compilation> Driver::buildCompilation(
     ArgList->hasArg(options::OPT_driver_skip_execution);
   bool ShowIncrementalBuildDecisions =
     ArgList->hasArg(options::OPT_driver_show_incremental);
+  bool ShowJobLifecycle =
+    ArgList->hasArg(options::OPT_driver_show_job_lifecycle);
 
   bool Incremental = ArgList->hasArg(options::OPT_incremental);
   if (ArgList->hasArg(options::OPT_whole_module_optimization)) {
@@ -642,9 +644,12 @@ std::unique_ptr<Compilation> Driver::buildCompilation(
       ContinueBuildingAfterErrors)
     C->setContinueBuildingAfterErrors();
 
-  if (ShowIncrementalBuildDecisions)
+  if (ShowIncrementalBuildDecisions || ShowJobLifecycle)
     C->setShowsIncrementalBuildDecisions();
 
+  if (ShowJobLifecycle)
+    C->setShowJobLifecycle();
+
   // This has to happen after building jobs, because otherwise we won't even
   // emit .swiftdeps files for the next build.
   if (rebuildEverything)

test/Driver/Dependencies/only-skip-once.swift

@@ -2,7 +2,7 @@
 // RUN: rm -rf %t && cp -r %S/Inputs/only-skip-once/ %t
 // RUN: touch -t 201401240005 %t/*
 
-// RUN: cd %t && %swiftc_driver -driver-show-incremental -output-file-map %t/output-file-map.json -incremental main.swift file1.swift file2.swift -j1 2>&1 | %FileCheck -check-prefix=CHECK-INITIAL %s
+// RUN: cd %t && %swiftc_driver -driver-show-job-lifecycle -output-file-map %t/output-file-map.json -incremental main.swift file1.swift file2.swift -j1 2>&1 | %FileCheck -check-prefix=CHECK-INITIAL %s
 
 // CHECK-INITIAL-NOT: warning
 // CHECK-INITIAL: Job finished: {compile: main.o <= main.swift}
@@ -11,7 +11,7 @@
 // CHECK-INITIAL: Job finished: {link: main <= main.o file1.o file2.o}
 
 // RUN: touch -t 201401240006 %t/file2.swift
-// RUN: cd %t && %swiftc_driver -driver-show-incremental -output-file-map %t/output-file-map.json -incremental main.swift file1.swift file2.swift -j1 2>&1 | %FileCheck -check-prefix=CHECK-REBUILD %s
+// RUN: cd %t && %swiftc_driver -driver-show-job-lifecycle -output-file-map %t/output-file-map.json -incremental main.swift file1.swift file2.swift -j1 2>&1 | %FileCheck -check-prefix=CHECK-REBUILD %s
 
 // We should skip the main and file1 rebuilds here, but we should only note skipping them _once_
 // CHECK-REBUILD: Job finished: {compile: file2.o <= file2.swift}