[turbofan] Make Pipeline more private.

By now the Pipeline class can no longer be used to construct instances
from the outside. The constructor and all non-exposed helpers can be
made private.

R=bmeurer@chromium.org

Review-Url: https://codereview.chromium.org/1943243003
Cr-Commit-Position: refs/heads/master@{#35978}

src/compiler/pipeline.cc

@@ -505,6 +505,8 @@ PipelineStatistics* CreatePipelineStatistics(CompilationInfo* info,
   return pipeline_statistics;
 }
 
+}  // namespace
+
 class PipelineCompilationJob final : public CompilationJob {
  public:
   PipelineCompilationJob(Isolate* isolate, Handle<JSFunction> function)
@@ -587,8 +589,6 @@ PipelineCompilationJob::Status PipelineCompilationJob::GenerateCodeImpl() {
   return SUCCEEDED;
 }
 
-}  // namespace
-
 class PipelineWasmCompilationJob final : public CompilationJob {
  public:
   explicit PipelineWasmCompilationJob(CompilationInfo* info, Graph* graph,

src/compiler/pipeline.h

@@ -28,19 +28,13 @@ class SourcePositionTable;
 
 class Pipeline {
  public:
-  explicit Pipeline(PipelineData* data) : data_(data) {}
-
-  // Run the graph creation and initial optimization passes.
-  bool CreateGraph();
-
-  // Run the concurrent optimization passes.
-  bool OptimizeGraph(Linkage* linkage);
-
-  // Perform the actual code generation and return handle to a code object.
-  Handle<Code> GenerateCode(Linkage* linkage);
+  // Returns a new compilation job for the given function.
+  static CompilationJob* NewCompilationJob(Handle<JSFunction> function);
 
-  // Run the entire pipeline and generate a handle to a code object.
-  Handle<Code> GenerateCode();
+  // Returns a new compilation job for the WebAssembly compilation info.
+  static CompilationJob* NewWasmCompilationJob(
+      CompilationInfo* info, Graph* graph, CallDescriptor* descriptor,
+      SourcePositionTable* source_positions);
 
   // Run the pipeline on a machine graph and generate code. The {schedule} must
   // be valid, hence the given {graph} does not need to be schedulable.
@@ -72,19 +66,12 @@ class Pipeline {
                                              Graph* graph,
                                              Schedule* schedule = nullptr);
 
-  // Returns a new compilation job for the given function.
-  static CompilationJob* NewCompilationJob(Handle<JSFunction> function);
-
-  // Returns a new compilation job for the WebAssembly compilation info.
-  static CompilationJob* NewWasmCompilationJob(
-      CompilationInfo* info, Graph* graph, CallDescriptor* descriptor,
-      SourcePositionTable* source_positions);
-
  private:
-  // The wasm compilation job calls ScheduleAndSelectInstructions and
-  // RunPrintAndVerify, so we make it a member class.
+  friend class PipelineCompilationJob;
   friend class PipelineWasmCompilationJob;
 
+  explicit Pipeline(PipelineData* data) : data_(data) {}
+
   // Helpers for executing pipeline phases.
   template <typename Phase>
   void Run();
@@ -93,6 +80,18 @@ class Pipeline {
   template <typename Phase, typename Arg0, typename Arg1>
   void Run(Arg0 arg_0, Arg1 arg_1);
 
+  // Run the graph creation and initial optimization passes.
+  bool CreateGraph();
+
+  // Run the concurrent optimization passes.
+  bool OptimizeGraph(Linkage* linkage);
+
+  // Perform the actual code generation and return handle to a code object.
+  Handle<Code> GenerateCode(Linkage* linkage);
+
+  // Run the entire pipeline and generate a handle to a code object.
+  Handle<Code> GenerateCode();
+
   void BeginPhaseKind(const char* phase_kind);
   void EndPhaseKind();
   bool ScheduleAndSelectInstructions(Linkage* linkage);