[turbofan] Split CodeGenerator::GenerateCode into AssembleCode and FinishCodeObject.

src/compiler/code-generator.h

Index: src/compiler/code-generator.h
diff --git a/src/compiler/code-generator.h b/src/compiler/code-generator.h
index ff8e5b9368b65a52ebef8b341f92cd088bbc607d..8e56ea0e18c8d581ce87d8ed205479fcefc5626a 100644
--- a/src/compiler/code-generator.h
+++ b/src/compiler/code-generator.h
@@ -48,17 +48,20 @@ class InstructionOperandIterator {
 // Generates native code for a sequence of instructions.
 class CodeGenerator final : public GapResolver::Assembler {
  public:
-  explicit CodeGenerator(Frame* frame, Linkage* linkage,
-                         InstructionSequence* code, CompilationInfo* info);
+  explicit CodeGenerator(Zone* zone, CompilationInfo* info);

[Michael Starzinger, 2016/08/11 14:16:26]

nit: Doesn't need to be "explicit" with more than one argument.

[ahaas, 2016/08/11 14:54:19]

Done.

 
+  void Initialize(Frame* frame, Linkage* linkage, InstructionSequence* code);

[Michael Starzinger, 2016/08/11 14:16:26]

nit: Can we add a "// Initialize before calling assembling or finishing code
object."

[ahaas, 2016/08/11 14:54:19]

Done.

   // Generate native code.

[Michael Starzinger, 2016/08/11 14:16:26]

nit: Empty whitespace between declarations for readability. Also lets adapt the
comment to make clear that this can be run off the main thread.

[ahaas, 2016/08/11 14:54:19]

Done.

-  Handle<Code> GenerateCode();
+  bool AssembleCode();
+  // Finishes the code object generated in AssembleCode.

[Michael Starzinger, 2016/08/11 14:16:26]

nit: Empty whitespace between declarations for readability. Also it might be
good to mention that this will return an empty handle when AssembleCode failed
or wasn't called (to clarify that is is safe to call).

[ahaas, 2016/08/11 14:54:19]

Done.

+  Handle<Code> FinishCodeObject();
 
   InstructionSequence* code() const { return code_; }
   FrameAccessState* frame_access_state() const { return frame_access_state_; }
   const Frame* frame() const { return frame_access_state_->frame(); }
   Isolate* isolate() const { return info_->isolate(); }
   Linkage* linkage() const { return linkage_; }
+  bool assemble_code_successful() { return assemble_code_successful_; }
 
   Label* GetLabel(RpoNumber rpo) { return &labels_[rpo.ToSize()]; }
 
@@ -69,9 +72,6 @@ class CodeGenerator final : public GapResolver::Assembler {
   Zone* zone() const { return code()->zone(); }
   CompilationInfo* info() const { return info_; }
 
-  // Create the FrameAccessState object. The Frame is immutable from here on.
-  void CreateFrameAccessState(Frame* frame);
-
   // Architecture - specific frame finalization.
   void FinishFrame(Frame* frame);
 
@@ -257,11 +257,11 @@ class CodeGenerator final : public GapResolver::Assembler {
   friend class OutOfLineCode;
 
   FrameAccessState* frame_access_state_;
-  Linkage* const linkage_;
-  InstructionSequence* const code_;
+  Linkage* linkage_;
+  InstructionSequence* code_;
   UnwindingInfoWriter unwinding_info_writer_;
   CompilationInfo* const info_;
-  Label* const labels_;
+  Label* labels_;
   Label return_label_;
   RpoNumber current_block_;
   SourcePosition current_source_position_;
@@ -279,6 +279,7 @@ class CodeGenerator final : public GapResolver::Assembler {
   OutOfLineCode* ools_;
   int osr_pc_offset_;
   SourcePositionTableBuilder source_position_table_builder_;
+  bool assemble_code_successful_;
 };
 
 }  // namespace compiler