[Driver] Load the standard library before starting parallel frontend invocations

Add a new action, LoadModuleJobAction, that the driver can use to schedule a
load of a given module before we fan out and invoke the frontend multiple
times. This gives the module interface loader a chance to compile it from a
module interface before we start with parallel invocations, avoiding starting
potentially dozens of redundant compiles of a large module. Start by using this
on the standard library.

Quick fix for rdar://52839445

include/swift/Driver/Action.h

@@ -52,9 +52,10 @@ public:
     GenerateDSYMJob,
     VerifyDebugInfoJob,
     GeneratePCHJob,
+    LoadModuleJob,
 
     JobFirst = CompileJob,
-    JobLast = GeneratePCHJob
+    JobLast = LoadModuleJob
   };
 
   static const char *getClassName(Kind AC);
@@ -338,6 +339,24 @@ public:
   }
 };
 
+/// An action that will attempt to load a specific module before any other
+/// actions.
+class LoadModuleJobAction : public JobAction {
+  virtual void anchor();
+  std::string moduleName;
+
+  public:
+  LoadModuleJobAction(StringRef moduleName)
+    : JobAction(Action::Kind::LoadModuleJob, {}, file_types::TY_Nothing),
+      moduleName(moduleName) {}
+
+  StringRef getModuleName() const { return moduleName; }
+
+  static bool classof(const Action *A) {
+    return A->getKind() == Action::Kind::LoadModuleJob;
+  }
+};
+
 } // end namespace driver
 } // end namespace swift
 

include/swift/Driver/ToolChain.h

@@ -164,6 +164,9 @@ protected:
   virtual InvocationInfo constructInvocation(const StaticLinkJobAction &job,
                                              const JobContext &context) const;
 
+  virtual InvocationInfo constructInvocation(const LoadModuleJobAction &job,
+                                             const JobContext &context) const;
+
   /// Searches for the given executable in appropriate paths relative to the
   /// Swift binary.
   ///

lib/Driver/Action.cpp

@@ -33,6 +33,7 @@ const char *Action::getClassName(Kind AC) {
   case Kind::GenerateDSYMJob:  return "generate-dSYM";
   case Kind::VerifyDebugInfoJob:  return "verify-debug-info";
   case Kind::GeneratePCHJob:  return "generate-pch";
+  case Kind::LoadModuleJob:  return "load-module";
   }
 
   llvm_unreachable("invalid class");
@@ -65,3 +66,5 @@ void GenerateDSYMJobAction::anchor() {}
 void VerifyDebugInfoJobAction::anchor() {}
 
 void GeneratePCHJobAction::anchor() {}
+
+void LoadModuleJobAction::anchor() {}

lib/Driver/Driver.cpp

@@ -1731,6 +1731,25 @@ Driver::computeCompilerMode(const DerivedArgList &Args,
   return OutputInfo::Mode::SingleCompile;
 }
 
+/// Determines whether the given set of inputs has multiple .swift, .sil, or
+/// .sib inputs, which will require loading the standard library.
+static bool hasMultipleSourceFileInputs(ArrayRef<InputPair> inputs) {
+  bool hasFoundOneSourceFileAlready = false;
+  for (const InputPair &input : inputs) {
+    switch (input.first) {
+    case file_types::TY_Swift:
+    case file_types::TY_SIL:
+    case file_types::TY_SIB:
+      if (hasFoundOneSourceFileAlready)
+        return true;
+      hasFoundOneSourceFileAlready = true;
+      break;
+    default: break;
+    }
+  }
+  return false;
+}
+
 void Driver::buildActions(SmallVectorImpl<const Action *> &TopLevelActions,
                           const ToolChain &TC, const OutputInfo &OI,
                           const InputInfoMap *OutOfDateMap,
@@ -1749,6 +1768,18 @@ void Driver::buildActions(SmallVectorImpl<const Action *> &TopLevelActions,
   switch (OI.CompilerMode) {
   case OutputInfo::Mode::StandardCompile: {
 
+    // If we're not compiling the standard library, and we're going to schedule
+    // multiple parallel compile jobs, add an action before any others that
+    // will quickly load the standard library module.
+    // This will ensure that, if we need to build the standard library from
+    // a module interface, it happens once, rather than once per parallel
+    // invocation.
+    LoadModuleJobAction *preLoadStdlib = nullptr;
+    if (!Args.hasArg(options::OPT_parse_stdlib) &&
+        hasMultipleSourceFileInputs(Inputs)) {
+      preLoadStdlib = C.createAction<LoadModuleJobAction>(STDLIB_NAME);
+    }
+
     // If the user is importing a textual (.h) bridging header and we're in
     // standard-compile (non-WMO) mode, we take the opportunity to precompile
     // the header into a temporary PCH, and replace the import argument with the
@@ -1772,6 +1803,15 @@ void Driver::buildActions(SmallVectorImpl<const Action *> &TopLevelActions,
       }
     }
 
+    // Adds the implicit dependencies for this job action, either generating
+    // a PCH, or pre-loading the standard library, or both.
+    auto addImplicitDeps = [&](Action *action) {
+      if (PCH)
+        cast<JobAction>(action)->addInput(PCH);
+      if (preLoadStdlib)
+        cast<JobAction>(action)->addInput(preLoadStdlib);
+    };
+
     for (const InputPair &Input : Inputs) {
       file_types::ID InputType = Input.first;
       const Arg *InputArg = Input.second;
@@ -1793,8 +1833,7 @@ void Driver::buildActions(SmallVectorImpl<const Action *> &TopLevelActions,
         if (Args.hasArg(options::OPT_embed_bitcode)) {
           Current = C.createAction<CompileJobAction>(
               Current, file_types::TY_LLVM_BC, previousBuildState);
-          if (PCH)
-            cast<JobAction>(Current)->addInput(PCH);
+          addImplicitDeps(Current);
           AllModuleInputs.push_back(Current);
           Current = C.createAction<BackendJobAction>(Current,
                                                      OI.CompilerOutputType, 0);
@@ -1802,8 +1841,7 @@ void Driver::buildActions(SmallVectorImpl<const Action *> &TopLevelActions,
           Current = C.createAction<CompileJobAction>(Current,
                                                      OI.CompilerOutputType,
                                                      previousBuildState);
-          if (PCH)
-            cast<JobAction>(Current)->addInput(PCH);
+          addImplicitDeps(Current);
           AllModuleInputs.push_back(Current);
         }
         AllLinkerInputs.push_back(Current);

lib/Driver/Job.cpp

@@ -383,9 +383,14 @@ void Job::printSummary(raw_ostream &os) const {
     if (const auto *IA = dyn_cast<InputAction>(A))
       Inputs.push_back(IA->getInputArg().getValue());
 
-  for (const Job *J : getInputs())
+  for (const Job *J : getInputs()) {
+    // Some jobs might produce no output, so don't include them in the
+    // list of inputs.
+    if (J->getOutput().getPrimaryOutputType() == file_types::TY_Nothing)
+      continue;
     for (StringRef f : J->getOutput().getPrimaryOutputFilenames())
       Inputs.push_back(f);
+  }
 
   size_t limit = 3;
   size_t actual_in = Inputs.size();

lib/Driver/ParseableOutput.cpp

@@ -146,13 +146,27 @@ public:
     });
   }
 
+  /// Subclasses can override this to determine if they should print empty
+  /// arrays for `inputs` and `output`, or if they can omit them.
+  virtual bool requireInputsAndOutputs() {
+    return false;
+  }
+
   void provideMapping(swift::json::Output &out) override {
     Message::provideMapping(out);
     out.mapRequired("command", CommandLine); // Deprecated, do not document
     out.mapRequired("command_executable", Executable);
     out.mapRequired("command_arguments", Arguments);
-    out.mapOptional("inputs", Inputs);
-    out.mapOptional("outputs", Outputs);
+
+    // Some commands can choose to print empty arrays if their inputs and
+    // outputs are empty.
+    if (requireInputsAndOutputs()) {
+      out.mapRequired("inputs", Inputs);
+      out.mapRequired("outputs", Outputs);
+    } else {
+      out.mapOptional("inputs", Inputs);
+      out.mapOptional("outputs", Outputs);
+    }
   }
 };
 
@@ -177,6 +191,12 @@ public:
       : DetailedCommandBasedMessage("began", Cmd), Pid(Pid),
         ProcInfo(ProcInfo) {}
 
+  bool requireInputsAndOutputs() override {
+    /// `began` messages should always print inputs and outputs, even if they
+    /// are empty.
+    return true;
+  }
+
   void provideMapping(swift::json::Output &out) override {
     DetailedCommandBasedMessage::provideMapping(out);
     out.mapRequired("pid", Pid);

lib/Driver/ToolChain.cpp

@@ -106,6 +106,7 @@ std::unique_ptr<Job> ToolChain::constructJob(
       CASE(GeneratePCHJob)
       CASE(AutolinkExtractJob)
       CASE(REPLJob)
+      CASE(LoadModuleJob)
 #undef CASE
     case Action::Kind::Input:
       llvm_unreachable("not a JobAction");

lib/Driver/ToolChains.cpp

@@ -1113,6 +1113,40 @@ ToolChain::constructInvocation(const StaticLinkJobAction &job,
    llvm_unreachable("archiving not implemented for this toolchain");
 }
 
+ToolChain::InvocationInfo
+ToolChain::constructInvocation(const LoadModuleJobAction &job,
+                               const JobContext &context) const {
+
+  // Invoke the frontend, passing `-import-module ModuleName` for whatever
+  // module the job is supposed to load.
+
+  InvocationInfo II{SWIFT_EXECUTABLE_NAME};
+  ArgStringList &Arguments = II.Arguments;
+  II.allowsResponseFiles = true;
+
+  for (auto &s : getDriver().getSwiftProgramArgs())
+    Arguments.push_back(s.c_str());
+
+  Arguments.push_back("-frontend");
+  Arguments.push_back("-typecheck");
+
+  // Force importing the module that this job specifies.
+
+  Arguments.push_back("-import-module");
+  Arguments.push_back(context.Args.MakeArgString(job.getModuleName()));
+
+  // Pass along the relevant arguments to the frontend invocation.
+
+  addCommonFrontendArgs(*this, context.OI, context.Output, context.Args,
+                        Arguments);
+
+  // Create an empty temporary file to typecheck.
+  auto tempFile = context.getTemporaryFilePath("tmp", "swift");
+  Arguments.push_back(context.Args.MakeArgString(tempFile));
+
+  return II;
+}
+
 void ToolChain::addPathEnvironmentVariableIfNeeded(
     Job::EnvironmentVector &env, const char *name, const char *separator,
     options::ID optionID, const ArgList &args,

test/Driver/Dependencies/Inputs/fake-build-for-bitcode.py

@@ -23,6 +23,11 @@ import sys
 
 assert sys.argv[1] == '-frontend'
 
+# If we're handling a frontend action that doesn't produce output or have a
+# primary-file, (e.g. a -typecheck action), then don't do anything.
+if '-primary-file' not in sys.argv or '-o' not in sys.argv:
+    sys.exit(0)
+
 primaryFile = sys.argv[sys.argv.index('-primary-file') + 1]
 outputFile = sys.argv[sys.argv.index('-o') + 1]
 

test/Driver/Dependencies/Inputs/modify-non-primary-files.py

@@ -23,6 +23,11 @@ import sys
 
 assert sys.argv[1] == '-frontend'
 
+# If we're handling a frontend action that doesn't produce output
+# (e.g. a -typecheck action), then don't do anything.
+if '-o' not in sys.argv:
+    sys.exit(0)
+
 if '-primary-file' in sys.argv:
     primaryFileIndex = sys.argv.index('-primary-file') + 1
     primaryFile = sys.argv[primaryFileIndex]

test/Driver/Dependencies/Inputs/update-dependencies-bad.py

@@ -26,6 +26,11 @@ import sys
 
 assert sys.argv[1] == '-frontend'
 
+# If we don't have a -primary-file, for example if this is a -typecheck job,
+# then don't do anything with this script.
+if '-primary-file' not in sys.argv:
+    sys.exit(0)
+
 primaryFile = sys.argv[sys.argv.index('-primary-file') + 1]
 
 if (os.path.basename(primaryFile) == 'bad.swift' or

test/Driver/Dependencies/Inputs/update-dependencies.py

@@ -35,6 +35,11 @@ import sys
 
 assert sys.argv[1] == '-frontend'
 
+# If we're handling a frontend action that doesn't produce output
+# (e.g. a -typecheck action), then don't do anything.
+if '-o' not in sys.argv:
+    sys.exit(0)
+
 # NB: The bitcode options automatically specify a -primary-file, even in cases
 #     where we do not wish to use a dependencies file in the test.
 if '-primary-file' in sys.argv \

test/Driver/Dependencies/bindings-build-record-options.swift

@@ -5,21 +5,21 @@
 // RUN: cd %t && %swiftc_driver -c -module-name main -driver-print-bindings ./main.swift ./other.swift ./yet-another.swift -incremental -output-file-map %t/output.json 2>&1 | %FileCheck %s -check-prefix=MUST-EXEC-INITIAL
 
 // MUST-EXEC-INITIAL-NOT: warning
-// MUST-EXEC-INITIAL: inputs: ["./main.swift"], output: {{[{].*[}]}}, condition: run-without-cascading
-// MUST-EXEC-INITIAL: inputs: ["./other.swift"], output: {{[{].*[}]}}, condition: run-without-cascading
-// MUST-EXEC-INITIAL: inputs: ["./yet-another.swift"], output: {{[{].*[}]}}, condition: run-without-cascading
+// MUST-EXEC-INITIAL: inputs: ["./main.swift", ""], output: {{[{].*[}]}}, condition: run-without-cascading
+// MUST-EXEC-INITIAL: inputs: ["./other.swift", ""], output: {{[{].*[}]}}, condition: run-without-cascading
+// MUST-EXEC-INITIAL: inputs: ["./yet-another.swift", ""], output: {{[{].*[}]}}, condition: run-without-cascading
 
 // MUST-EXEC-ALL-NOT: warning
-// MUST-EXEC-ALL: inputs: ["./main.swift"], output: {{[{].*[}]$}}
-// MUST-EXEC-ALL: inputs: ["./other.swift"], output: {{[{].*[}]$}}
-// MUST-EXEC-ALL: inputs: ["./yet-another.swift"], output: {{[{].*[}]$}}
+// MUST-EXEC-ALL: inputs: ["./main.swift", ""], output: {{[{].*[}]$}}
+// MUST-EXEC-ALL: inputs: ["./other.swift", ""], output: {{[{].*[}]$}}
+// MUST-EXEC-ALL: inputs: ["./yet-another.swift", ""], output: {{[{].*[}]$}}
 
 // RUN: cd %t && %swiftc_driver -c -module-name main -driver-use-frontend-path "%{python};%S/Inputs/update-dependencies.py" ./main.swift ./other.swift ./yet-another.swift -incremental -output-file-map %t/output.json
 // RUN: cd %t && %swiftc_driver -c -module-name main -driver-print-bindings ./main.swift ./other.swift ./yet-another.swift -incremental -output-file-map %t/output.json 2>&1 | %FileCheck %s -check-prefix=NO-EXEC
 
-// NO-EXEC: inputs: ["./main.swift"], output: {{[{].*[}]}}, condition: check-dependencies
-// NO-EXEC: inputs: ["./other.swift"], output: {{[{].*[}]}}, condition: check-dependencies
-// NO-EXEC: inputs: ["./yet-another.swift"], output: {{[{].*[}]}}, condition: check-dependencies
+// NO-EXEC: inputs: ["./main.swift", ""], output: {{[{].*[}]}}, condition: check-dependencies
+// NO-EXEC: inputs: ["./other.swift", ""], output: {{[{].*[}]}}, condition: check-dependencies
+// NO-EXEC: inputs: ["./yet-another.swift", ""], output: {{[{].*[}]}}, condition: check-dependencies
 
 
 // RUN: cd %t && %swiftc_driver -c -module-name main -driver-print-bindings -serialize-diagnostics ./main.swift ./other.swift ./yet-another.swift -incremental -output-file-map %t/output.json 2>&1 | %FileCheck %s -check-prefix=NO-EXEC

test/Driver/Dependencies/bindings-build-record.swift

@@ -6,41 +6,41 @@
 // RUN: cd %t && %swiftc_driver -driver-print-bindings ./main.swift ./other.swift ./yet-another.swift -incremental -output-file-map %t/output.json 2>&1 | %FileCheck %s -check-prefix=MUST-EXEC
 
 // MUST-EXEC-NOT: warning
-// MUST-EXEC: inputs: ["./main.swift"], output: {{[{].*[}]}}, condition: run-without-cascading
-// MUST-EXEC: inputs: ["./other.swift"], output: {{[{].*[}]}}, condition: run-without-cascading
-// MUST-EXEC: inputs: ["./yet-another.swift"], output: {{[{].*[}]}}, condition: run-without-cascading
+// MUST-EXEC: inputs: ["./main.swift", ""], output: {{[{].*[}]}}, condition: run-without-cascading
+// MUST-EXEC: inputs: ["./other.swift", ""], output: {{[{].*[}]}}, condition: run-without-cascading
+// MUST-EXEC: inputs: ["./yet-another.swift", ""], output: {{[{].*[}]}}, condition: run-without-cascading
 
 // RUN: echo '{version: "'$(%swiftc_driver_plain -version | head -n1)'", inputs: {"./main.swift": [443865900, 0], "./other.swift": [443865900, 0], "./yet-another.swift": [443865900, 0]}, build_time: [443865901, 0]}' > %t/main~buildrecord.swiftdeps
 // RUN: cd %t && %swiftc_driver -driver-print-bindings ./main.swift ./other.swift ./yet-another.swift -incremental -output-file-map %t/output.json 2>&1 | %FileCheck %s -check-prefix=NO-EXEC
 
-// NO-EXEC: inputs: ["./main.swift"], output: {{[{].*[}]}}, condition: check-dependencies
-// NO-EXEC: inputs: ["./other.swift"], output: {{[{].*[}]}}, condition: check-dependencies
-// NO-EXEC: inputs: ["./yet-another.swift"], output: {{[{].*[}]}}, condition: check-dependencies
+// NO-EXEC: inputs: ["./main.swift", ""], output: {{[{].*[}]}}, condition: check-dependencies
+// NO-EXEC: inputs: ["./other.swift", ""], output: {{[{].*[}]}}, condition: check-dependencies
+// NO-EXEC: inputs: ["./yet-another.swift", ""], output: {{[{].*[}]}}, condition: check-dependencies
 
 
 // RUN: echo '{version: "'$(%swiftc_driver_plain -version | head -n1)'", inputs: {"./main.swift": [443865900, 0], "./other.swift": !private [443865900, 0], "./yet-another.swift": !dirty [443865900, 0]}, build_time: [443865901, 0]}' > %t/main~buildrecord.swiftdeps
 // RUN: cd %t && %swiftc_driver -driver-print-bindings ./main.swift ./other.swift ./yet-another.swift -incremental -output-file-map %t/output.json 2>&1 | %FileCheck %s -check-prefix=BUILD-RECORD
 
-// BUILD-RECORD: inputs: ["./main.swift"], output: {{[{].*[}]}}, condition: check-dependencies{{$}}
-// BUILD-RECORD: inputs: ["./other.swift"], output: {{[{].*[}]}}, condition: run-without-cascading{{$}}
-// BUILD-RECORD: inputs: ["./yet-another.swift"], output: {{[{].*[}]$}}
+// BUILD-RECORD: inputs: ["./main.swift", ""], output: {{[{].*[}]}}, condition: check-dependencies{{$}}
+// BUILD-RECORD: inputs: ["./other.swift", ""], output: {{[{].*[}]}}, condition: run-without-cascading{{$}}
+// BUILD-RECORD: inputs: ["./yet-another.swift", ""], output: {{[{].*[}]$}}
 
 // RUN: cd %t && %swiftc_driver -driver-print-bindings ./main.swift ./other.swift ./yet-another.swift ./added.swift -incremental -output-file-map %t/output.json 2>&1 > %t/added.txt
 // RUN: %FileCheck %s -check-prefix=BUILD-RECORD < %t/added.txt
 // RUN: %FileCheck %s -check-prefix=FILE-ADDED < %t/added.txt
 
-// FILE-ADDED: inputs: ["./added.swift"], output: {{[{].*[}]}}, condition: newly-added{{$}}
+// FILE-ADDED: inputs: ["./added.swift", ""], output: {{[{].*[}]}}, condition: newly-added{{$}}
 
 // RUN: %{python} %S/Inputs/touch.py 443865960 %t/main.swift
 // RUN: cd %t && %swiftc_driver -driver-print-bindings ./main.swift ./other.swift ./yet-another.swift -incremental -output-file-map %t/output.json 2>&1 | %FileCheck %s -check-prefix=BUILD-RECORD-PLUS-CHANGE
-// BUILD-RECORD-PLUS-CHANGE: inputs: ["./main.swift"], output: {{[{].*[}]}}, condition: run-without-cascading
-// BUILD-RECORD-PLUS-CHANGE: inputs: ["./other.swift"], output: {{[{].*[}]}}, condition: run-without-cascading{{$}}
-// BUILD-RECORD-PLUS-CHANGE: inputs: ["./yet-another.swift"], output: {{[{].*[}]$}}
+// BUILD-RECORD-PLUS-CHANGE: inputs: ["./main.swift", ""], output: {{[{].*[}]}}, condition: run-without-cascading
+// BUILD-RECORD-PLUS-CHANGE: inputs: ["./other.swift", ""], output: {{[{].*[}]}}, condition: run-without-cascading{{$}}
+// BUILD-RECORD-PLUS-CHANGE: inputs: ["./yet-another.swift", ""], output: {{[{].*[}]$}}
 
 // RUN: %{python} %S/Inputs/touch.py 443865900 %t/*
 // RUN: cd %t && %swiftc_driver -driver-print-bindings ./main.swift ./other.swift -incremental -output-file-map %t/output.json 2>&1 | %FileCheck %s -check-prefix=FILE-REMOVED
-// FILE-REMOVED: inputs: ["./main.swift"], output: {{[{].*[}]$}}
-// FILE-REMOVED: inputs: ["./other.swift"], output: {{[{].*[}]$}}
+// FILE-REMOVED: inputs: ["./main.swift", ""], output: {{[{].*[}]$}}
+// FILE-REMOVED: inputs: ["./other.swift", ""], output: {{[{].*[}]$}}
 // FILE-REMOVED-NOT: yet-another.swift
 
 
@@ -48,6 +48,6 @@
 // RUN: cd %t && %swiftc_driver -driver-print-bindings ./main.swift ./other.swift ./yet-another.swift -incremental -output-file-map %t/output.json 2>&1 | %FileCheck %s -check-prefix=INVALID-RECORD
 
 // INVALID-RECORD-NOT: warning
-// INVALID-RECORD: inputs: ["./main.swift"], output: {{[{].*[}]$}}
-// INVALID-RECORD: inputs: ["./other.swift"], output: {{[{].*[}]$}}
-// INVALID-RECORD: inputs: ["./yet-another.swift"], output: {{[{].*[}]$}}
+// INVALID-RECORD: inputs: ["./main.swift", ""], output: {{[{].*[}]$}}
+// INVALID-RECORD: inputs: ["./other.swift", ""], output: {{[{].*[}]$}}
+// INVALID-RECORD: inputs: ["./yet-another.swift", ""], output: {{[{].*[}]$}}

test/Driver/Dependencies/driver-show-incremental-mutual.swift

@@ -8,7 +8,7 @@
 // CHECK-FIRST: Queuing (initial): {compile: main.o <= main.swift}
 
 // RUN: cd %t && %swiftc_driver -c -driver-use-frontend-path "%{python};%S/Inputs/update-dependencies.py" -output-file-map %t/output.json -incremental -driver-always-rebuild-dependents ./main.swift ./other.swift -module-name main -j1 -v -driver-show-incremental 2>&1 | %FileCheck -check-prefix=CHECK-SECOND %s
-// CHECK-SECOND-NOT: Queuing
+// CHECK-SECOND-NOT: Queuing (initial): {compile
 
 // RUN: touch -t 201401240006 %t/other.swift
 // RUN: cd %t && %swiftc_driver -c -driver-use-frontend-path "%{python};%S/Inputs/update-dependencies.py" -output-file-map %t/output.json -incremental -driver-always-rebuild-dependents ./main.swift ./other.swift -module-name main -j1 -v -driver-show-incremental 2>&1 | %FileCheck -check-prefix=CHECK-THIRD %s

test/Driver/Dependencies/embed-bitcode-parallel.swift

@@ -7,6 +7,17 @@
 // RUN: cd %t && %swiftc_driver -c -driver-use-frontend-path "%{python};%S/Inputs/fake-build-for-bitcode.py" -output-file-map %t/output.json -incremental ./main.swift ./other.swift -embed-bitcode -module-name main -j1 -parseable-output 2>&1 | %FileCheck -check-prefix=CHECK-FIRST %s
 
 // CHECK-FIRST-NOT: warning
+
+// CHECK-FIRST: {{^{$}}
+// CHECK-FIRST: "kind": "began"
+// CHECK-FIRST: "name": "load-module"
+// CHECK-FIRST: {{^}$}}
+
+// CHECK-FIRST: {{^{$}}
+// CHECK-FIRST: "kind": "finished"
+// CHECK-FIRST: "name": "load-module"
+// CHECK-FIRST: {{^}$}}
+
 // CHECK-FIRST: {{^{$}}
 // CHECK-FIRST: "kind": "began"
 // CHECK-FIRST: "name": "compile"
@@ -59,6 +70,10 @@
 // RUN: touch -t 201401240006 %t/other.swift
 // RUN: cd %t && %swiftc_driver -c -driver-use-frontend-path "%{python};%S/Inputs/fake-build-for-bitcode.py" -output-file-map %t/output.json -incremental ./main.swift ./other.swift -embed-bitcode -module-name main -j2 -parseable-output 2>&1 | %FileCheck -check-prefix=CHECK-SECOND %s
 
+// CHECK-SECOND: "kind": "began"
+// CHECK-SECOND: "name": "load-module"
+// CHECK-SECOND: {{^}$}}
+
 // CHECK-SECOND: "kind": "began"
 // CHECK-SECOND: "name": "compile"
 // CHECK-SECOND: ".\/main.swift"

test/Driver/Inputs/filelists/check-filelist-abc.py

@@ -26,6 +26,11 @@ else:
 if primaryFile and primaryFile.endswith(".bc"):
     sys.exit()
 
+# If we're handling a frontend action that doesn't produce have a
+# filelist, (e.g. a -typecheck action), then don't do anything.
+if '-filelist' not in sys.argv:
+    sys.exit(0)
+
 filelistFile = sys.argv[sys.argv.index('-filelist') + 1]
 
 with open(filelistFile, 'r') as f:

test/Driver/actions-dsym.swift

@@ -61,15 +61,16 @@
 // RUN: %swiftc_driver -driver-print-actions -target x86_64-apple-macosx10.9 -g -gnone -emit-executable -emit-module %s 2>&1 | %FileCheck %s -check-prefix=EXEC-AND-MODULE
 
 // RUN: %swiftc_driver -driver-print-actions -target x86_64-apple-macosx10.9 -g %S/Inputs/main.swift %S/../Inputs/empty.swift %s -module-name actions 2>&1 | %FileCheck %s -check-prefix=DEBUG-MULTI
-// DEBUG-MULTI: 0: input, "{{.*}}Inputs/main.swift", swift
-// DEBUG-MULTI: 1: compile, {0}, object
-// DEBUG-MULTI: 2: input, "{{.*}}Inputs/empty.swift", swift
-// DEBUG-MULTI: 3: compile, {2}, object
-// DEBUG-MULTI: 4: input, "{{.*}}actions-dsym.swift", swift
-// DEBUG-MULTI: 5: compile, {4}, object
-// DEBUG-MULTI: 6: merge-module, {1, 3, 5}, swiftmodule
-// DEBUG-MULTI: 7: link, {1, 3, 5, 6}, image
-// DEBUG-MULTI: 8: generate-dSYM, {7}, dSYM
+// DEBUG-MULTI: 0: load-module, {}
+// DEBUG-MULTI: 1: input, "{{.*}}Inputs/main.swift", swift
+// DEBUG-MULTI: 2: compile, {1, 0}, object
+// DEBUG-MULTI: 3: input, "{{.*}}Inputs/empty.swift", swift
+// DEBUG-MULTI: 4: compile, {3, 0}, object
+// DEBUG-MULTI: 5: input, "{{.*}}actions-dsym.swift", swift
+// DEBUG-MULTI: 6: compile, {5, 0}, object
+// DEBUG-MULTI: 7: merge-module, {2, 4, 6}, swiftmodule
+// DEBUG-MULTI: 8: link, {2, 4, 6, 7}, image
+// DEBUG-MULTI: 9: generate-dSYM, {8}, dSYM
 
 
 // RUN: touch %t/a.o %t/b.o

test/Driver/actions.swift

@@ -108,30 +108,31 @@
 // RUN: %swiftc_driver -driver-print-actions -g -gnone -emit-executable -emit-module %s 2>&1 | %FileCheck %s -check-prefix=EXEC-AND-MODULE
 
 // RUN: %swiftc_driver -driver-print-actions %S/Inputs/main.swift %S/../Inputs/empty.swift %s -module-name actions 2>&1 | %FileCheck %s -check-prefix=MULTI -check-prefix MULTI-%target-object-format
-// MULTI: 0: input, "{{.*}}Inputs/main.swift", swift
-// MULTI: 1: compile, {0}, object
-// MULTI: 2: input, "{{.*}}Inputs/empty.swift", swift
-// MULTI: 3: compile, {2}, object
-// MULTI: 4: input, "{{.*}}actions.swift", swift
-// MULTI: 5: compile, {4}, object
-// MULTI-COFF: 6: link, {1, 3, 5}, image
-// MULTI-ELF: 6: swift-autolink-extract, {1, 3, 5}, autolink
-// MULTI-ELF: 7: link, {1, 3, 5, 6}, image
-// MULTI-MACHO: 6: link, {1, 3, 5}, image
+// MULTI: 0: load-module, {}
+// MULTI: 1: input, "{{.*}}Inputs/main.swift", swift
+// MULTI: 2: compile, {1, 0}, object
+// MULTI: 3: input, "{{.*}}Inputs/empty.swift", swift
+// MULTI: 4: compile, {3, 0}, object
+// MULTI: 5: input, "{{.*}}actions.swift", swift
+// MULTI: 6: compile, {5, 0}, object
+// MULTI-COFF: 7: link, {2, 4, 6}, image
+// MULTI-ELF: 7: swift-autolink-extract, {2, 4, 6}, autolink
+// MULTI-ELF: 8: link, {2, 4, 6, 7}, image
+// MULTI-MACHO: 7: link, {2, 4, 6}, image
 
 // RUN: %swiftc_driver -driver-print-actions -g %S/Inputs/main.swift %S/../Inputs/empty.swift %s -module-name actions 2>&1 | %FileCheck %s -check-prefix=DEBUG-MULTI -check-prefix DEBUG-MULTI-%target-object-format
-// DEBUG-MULTI: 0: input, "{{.*}}Inputs/main.swift", swift
-// DEBUG-MULTI: 1: compile, {0}, object
-// DEBUG-MULTI: 2: input, "{{.*}}Inputs/empty.swift", swift
-// DEBUG-MULTI: 3: compile, {2}, object
-// DEBUG-MULTI: 4: input, "{{.*}}actions.swift", swift
-// DEBUG-MULTI: 5: compile, {4}, object
-// DEBUG-MULTI: 6: merge-module, {1, 3, 5}, swiftmodule
-// DEBUG-MULTI-COFF: 7: modulewrap, {6}, object
-// DEBUG-MULTI-COFF: 8: link, {1, 3, 5, 7}, image
-// DEBUG-MULTI-ELF: 7: modulewrap, {6}, object
-// DEBUG-MULTI-ELF: 8: link, {1, 3, 5, 7}, image
-// DEBUG-MULTI-MACHO: 7: link, {1, 3, 5, 6}, image
+// DEBUG-MULTI: 1: input, "{{.*}}Inputs/main.swift", swift
+// DEBUG-MULTI: 2: compile, {1, 0}, object
+// DEBUG-MULTI: 3: input, "{{.*}}Inputs/empty.swift", swift
+// DEBUG-MULTI: 4: compile, {3, 0}, object
+// DEBUG-MULTI: 5: input, "{{.*}}actions.swift", swift
+// DEBUG-MULTI: 6: compile, {5, 0}, object
+// DEBUG-MULTI: 7: merge-module, {2, 4, 6}, swiftmodule
+// DEBUG-MULTI-COFF: 8: modulewrap, {7}, object
+// DEBUG-MULTI-COFF: 9: link, {2, 4, 6, 8}, image
+// DEBUG-MULTI-ELF: 8: modulewrap, {7}, object
+// DEBUG-MULTI-ELF: 9: link, {2, 4, 6, 8}, image
+// DEBUG-MULTI-MACHO: 8: link, {2, 4, 6, 7}, image
 
 
 // RUN: touch %t/a.o %t/b.o

test/Driver/advanced_output_file_map.swift

@@ -19,9 +19,9 @@
 // DUMPOFM-NEXT: {{.*}}/advanced_output_file_map.swift -> swiftdoc: "/build/swiftmodule/advanced_output_file_map_x.swiftdoc"
 // DUMPOFM-NEXT: {{.*}}/advanced_output_file_map.swift -> diagnostics: "/build/dia/advanced_output_file_map.dia"
 
-// BINDINGS: # "x86_64-apple-macosx10.9" - "swift{{c?(\.EXE)?}}", inputs: ["{{.*}}/advanced_output_file_map.swift"], output: {object: "/build/obj/advanced_output_file_map.o", dependencies: "/build/d/advanced_output_file_map.d", swiftmodule: "/build/swiftmodule/advanced_output_file_map.swiftmodule", swiftdoc: "/build/swiftmodule/advanced_output_file_map_x.swiftdoc", diagnostics: "/build/dia/advanced_output_file_map.dia"}
-// BINDINGS: # "x86_64-apple-macosx10.9" - "swift{{c?(\.EXE)?}}", inputs: ["{{.*}}/Inputs/main.swift"], output: {object: "/build/obj/main.o", dependencies: "/build/d/main.d", swiftmodule: "/build/swiftmodule/main.swiftmodule", swiftdoc: "/build/swiftmodule/main_x.swiftdoc", diagnostics: "/build/dia/main.dia"}
-// BINDINGS: # "x86_64-apple-macosx10.9" - "swift{{c?(\.EXE)?}}", inputs: ["{{.*}}/Inputs/lib.swift"], output: {object: "/build/obj/lib.o", dependencies: "/build/d/lib.d", swiftmodule: "/build/swiftmodule/lib.swiftmodule", swiftdoc: "/build/swiftmodule/lib_x.swiftdoc", diagnostics: "/build/dia/lib.dia"}
+// BINDINGS: # "x86_64-apple-macosx10.9" - "swift{{c?(\.EXE)?}}", inputs: ["{{.*}}/advanced_output_file_map.swift", ""], output: {object: "/build/obj/advanced_output_file_map.o", dependencies: "/build/d/advanced_output_file_map.d", swiftmodule: "/build/swiftmodule/advanced_output_file_map.swiftmodule", swiftdoc: "/build/swiftmodule/advanced_output_file_map_x.swiftdoc", diagnostics: "/build/dia/advanced_output_file_map.dia"}
+// BINDINGS: # "x86_64-apple-macosx10.9" - "swift{{c?(\.EXE)?}}", inputs: ["{{.*}}/Inputs/main.swift", ""], output: {object: "/build/obj/main.o", dependencies: "/build/d/main.d", swiftmodule: "/build/swiftmodule/main.swiftmodule", swiftdoc: "/build/swiftmodule/main_x.swiftdoc", diagnostics: "/build/dia/main.dia"}
+// BINDINGS: # "x86_64-apple-macosx10.9" - "swift{{c?(\.EXE)?}}", inputs: ["{{.*}}/Inputs/lib.swift", ""], output: {object: "/build/obj/lib.o", dependencies: "/build/d/lib.d", swiftmodule: "/build/swiftmodule/lib.swiftmodule", swiftdoc: "/build/swiftmodule/lib_x.swiftdoc", diagnostics: "/build/dia/lib.dia"}
 // BINDINGS: # "x86_64-apple-macosx10.9" - "swift{{c?(\.EXE)?}}", inputs: ["/build/obj/advanced_output_file_map.o", "/build/obj/main.o", "/build/obj/lib.o"], output: {swiftmodule: "/build/OutputFileMap.swiftmodule", swiftdoc: "/build/OutputFileMap.swiftdoc"}
 // BINDINGS: # "x86_64-apple-macosx10.9" - "ld{{(.exe)?}}", inputs: ["/build/obj/advanced_output_file_map.o", "/build/obj/main.o", "/build/obj/lib.o", "/build/OutputFileMap.swiftmodule"], output: {image: "/build/advanced_output_file_map.out"}
 // BINDINGS: # "x86_64-apple-macosx10.9" - "dsymutil{{(\.exe)?}}", inputs: ["/build/advanced_output_file_map.out"], output: {dSYM: "/build/advanced_output_file_map.out.dSYM"}

test/Driver/basic_output_file_map.swift

@@ -7,7 +7,7 @@
 // DUMPOFM: {{.*}}/Inputs/main.swift -> object: "/build/main.o"
 // DUMPOFM: {{.*}}/basic_output_file_map.swift -> object: "/build/basic_output_file_map.o"
 
-// BINDINGS: # "x86_64-apple-macosx10.9" - "swift{{c?(\.EXE)?}}", inputs: ["{{.*}}/basic_output_file_map.swift"], output: {object: "/build/basic_output_file_map.o"}
-// BINDINGS: # "x86_64-apple-macosx10.9" - "swift{{c?(\.EXE)?}}", inputs: ["{{.*}}/Inputs/main.swift"], output: {object: "/build/main.o"}
-// BINDINGS: # "x86_64-apple-macosx10.9" - "swift{{c?(\.EXE)?}}", inputs: ["{{.*}}/Inputs/lib.swift"], output: {object: "/build/lib.o"}
+// BINDINGS: # "x86_64-apple-macosx10.9" - "swift{{c?(\.EXE)?}}", inputs: ["{{.*}}/basic_output_file_map.swift", ""], output: {object: "/build/basic_output_file_map.o"}
+// BINDINGS: # "x86_64-apple-macosx10.9" - "swift{{c?(\.EXE)?}}", inputs: ["{{.*}}/Inputs/main.swift", ""], output: {object: "/build/main.o"}
+// BINDINGS: # "x86_64-apple-macosx10.9" - "swift{{c?(\.EXE)?}}", inputs: ["{{.*}}/Inputs/lib.swift", ""], output: {object: "/build/lib.o"}
 // BINDINGS: # "x86_64-apple-macosx10.9" - "ld{{(\.exe)?}}", inputs: ["/build/basic_output_file_map.o", "/build/main.o", "/build/lib.o"], output: {image: "/build/basic_output_file_map.out"}

test/Driver/batch_mode_parseable_output.swift

@@ -5,6 +5,39 @@
 // RUN: %swiftc_driver -enable-batch-mode -parseable-output -driver-skip-execution -c -emit-module -module-name main -j 2 %t/file-01.swift %t/file-02.swift %t/file-03.swift %t/main.swift 2>&1 | %FileCheck %s
 //
 //
+// CHECK: {{[1-9][0-9]*}}
+// CHECK-NEXT: {
+// CHECK-NEXT:   "kind": "began",
+// CHECK-NEXT:   "name": "load-module",
+// CHECK-NEXT:   "command": "{{.*[\\/]}}swift{{c?(\.EXE)?(\\")?}} -frontend -typecheck -import-module Swift {{.*}}tmp{{.*}}.swift",
+// CHECK-NEXT:   "command_executable": "{{.*[\\/]}}swift{{c?(\.EXE)?(\\")?}}",
+// CHECK-NEXT:   "command_arguments": [
+// CHECK-NEXT:     "-frontend",
+// CHECK-NEXT:     "-typecheck",
+// CHECK-NEXT:     "-import-module",
+// CHECK-NEXT:     "Swift",
+// CHECK:          "{{.*}}tmp{{.*}}.swift"
+// CHECK-NEXT:   ],
+// CHECK-NEXT:   "inputs": [],
+// CHECK-NEXT:   "outputs": [],
+// CHECK-NEXT:   "pid": {{[1-9][0-9]*}},
+// CHECK-NEXT:   "process": {
+// CHECK-NEXT:     "real_pid": {{[1-9][0-9]*}}
+// CHECK-NEXT:   }
+// CHECK-NEXT: }
+
+// CHECK: {{[1-9][0-9]*}}
+// CHECK-NEXT: {
+// CHECK-NEXT:   "kind": "finished",
+// CHECK-NEXT:   "name": "load-module",
+// CHECK-NEXT:   "pid": {{[1-9][0-9]*}},
+// CHECK-NEXT:   "output": "Output placeholder\n",
+// CHECK-NEXT:   "process": {
+// CHECK-NEXT:     "real_pid": {{[1-9][0-9]*}}
+// CHECK-NEXT:   },
+// CHECK-NEXT:   "exit-status": 0
+// CHECK-NEXT: }
+
 // CHECK: {{[1-9][0-9]*}}
 // CHECK-NEXT: {
 // CHECK-NEXT:   "kind": "began",
@@ -29,7 +62,8 @@
 // CHECK-NEXT:     "{{.*[\\/]}}file-01-[[OBJ01:[a-z0-9]+]].o"
 // CHECK-NEXT:   ],
 // CHECK-NEXT:   "inputs": [
-// CHECK-NEXT:     "{{.*[\\/]}}file-01.swift"
+// CHECK-NEXT:     "{{.*[\\/]}}file-01.swift",
+// CHECK-NEXT:     ""
 // CHECK-NEXT:   ],
 // CHECK-NEXT:   "outputs": [
 // CHECK-NEXT:     {
@@ -74,7 +108,8 @@
 // CHECK-NEXT:     "{{.*[\\/]}}file-02-[[OBJ02:[a-z0-9]+]].o"
 // CHECK-NEXT:   ],
 // CHECK-NEXT:   "inputs": [
-// CHECK-NEXT:     "{{.*[\\/]}}file-02.swift"
+// CHECK-NEXT:     "{{.*[\\/]}}file-02.swift",
+// CHECK-NEXT:     ""
 // CHECK-NEXT:   ],
 // CHECK-NEXT:   "outputs": [
 // CHECK-NEXT:     {
@@ -119,7 +154,8 @@
 // CHECK-NEXT:     "{{.*[\\/]}}file-03-[[OBJ03:[a-z0-9]+]].o"
 // CHECK-NEXT:   ],
 // CHECK-NEXT:   "inputs": [
-// CHECK-NEXT:     "{{.*[\\/]}}file-03.swift"
+// CHECK-NEXT:     "{{.*[\\/]}}file-03.swift",
+// CHECK-NEXT:     ""
 // CHECK-NEXT:   ],
 // CHECK-NEXT:   "outputs": [
 // CHECK-NEXT:     {
@@ -164,7 +200,8 @@
 // CHECK-NEXT:     "{{.*[\\/]}}main-[[OBJMAIN:[a-z0-9]+]].o"
 // CHECK-NEXT:   ],
 // CHECK-NEXT:   "inputs": [
-// CHECK-NEXT:     "{{.*[\\/]}}main.swift"
+// CHECK-NEXT:     "{{.*[\\/]}}main.swift",
+// CHECK-NEXT:     ""
 // CHECK-NEXT:   ],
 // CHECK-NEXT:   "outputs": [
 // CHECK-NEXT:     {

test/Driver/bridging-pch.swift

@@ -58,7 +58,7 @@
 // PERSISTENT-YESPCHJOB-DIAG2: {{.*}}swift{{c?(\.EXE)?"?}} -frontend {{.*}} -serialize-diagnostics-path {{.*}}/pch-out-dir{{/|\\\\}}bridging-header-{{.*}}.dia{{"?}} {{.*}} -emit-pch -pch-output-dir {{.*}}/pch-out-dir
 
 // RUN: %target-build-swift -typecheck -import-objc-header %S/Inputs/bridging-header.h -pch-output-dir %t/pch -parseable-output -driver-skip-execution %s 2>&1 | %FileCheck %s -check-prefix=PERSISTENT-OUTPUT
-// PERSISTENT-OUTPUT-NOT: "outputs": [
+// PERSISTENT-OUTPUT-NOT: "outputs": [{{$}}
 
 // RUN: %target-build-swift -typecheck -driver-print-jobs -import-objc-header %S/Inputs/bridging-header.h -pch-output-dir %t/pch -whole-module-optimization %s 2>&1 | %FileCheck %s -check-prefix=PERSISTENT-WMO-YESPCHJOB --implicit-check-not pch-disable-validation
 // PERSISTENT-WMO-YESPCHJOB: {{.*}}swift{{c?(\.EXE)?"?}} -frontend {{.*}} -import-objc-header {{.*}}bridging-header.h{{"?}} -pch-output-dir {{.*}}/pch