Reland of [ignition/turbo] Perform liveness analysis on the bytecodes

src/interpreter/control-flow-builders.h

 // Copyright 2015 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_INTERPRETER_CONTROL_FLOW_BUILDERS_H_
 #define V8_INTERPRETER_CONTROL_FLOW_BUILDERS_H_
 
 #include "src/interpreter/bytecode-array-builder.h"
 
 #include "src/interpreter/bytecode-label.h"
 #include "src/zone/zone-containers.h"
 
 namespace v8 {
 namespace internal {
 namespace interpreter {
 
-class ControlFlowBuilder BASE_EMBEDDED {
+class V8_EXPORT_PRIVATE ControlFlowBuilder BASE_EMBEDDED {
  public:
   explicit ControlFlowBuilder(BytecodeArrayBuilder* builder)
       : builder_(builder) {}
   virtual ~ControlFlowBuilder() {}
 
  protected:
   BytecodeArrayBuilder* builder() const { return builder_; }
 
  private:
   BytecodeArrayBuilder* builder_;
 
   DISALLOW_COPY_AND_ASSIGN(ControlFlowBuilder);
 };
 
-class BreakableControlFlowBuilder : public ControlFlowBuilder {
+class V8_EXPORT_PRIVATE BreakableControlFlowBuilder
+    : public ControlFlowBuilder {
  public:
   explicit BreakableControlFlowBuilder(BytecodeArrayBuilder* builder)
       : ControlFlowBuilder(builder), break_labels_(builder->zone()) {}
   virtual ~BreakableControlFlowBuilder();
 
   // This method should be called by the control flow owner before
   // destruction to update sites that emit jumps for break.
   void BindBreakTarget();
 
   // This method is called when visiting break statements in the AST.
@@ skipping 13 matching lines @@
   void EmitJumpIfFalse(BytecodeLabels* labels);
   void EmitJumpIfUndefined(BytecodeLabels* labels);
   void EmitJumpIfNull(BytecodeLabels* labels);
 
   // Unbound labels that identify jumps for break statements in the code.
   BytecodeLabels break_labels_;
 };
 
 
 // Class to track control flow for block statements (which can break in JS).
-class BlockBuilder final : public BreakableControlFlowBuilder {
+class V8_EXPORT_PRIVATE BlockBuilder final
+    : public BreakableControlFlowBuilder {
  public:
   explicit BlockBuilder(BytecodeArrayBuilder* builder)
       : BreakableControlFlowBuilder(builder) {}
 
   void EndBlock();
 
  private:
   BytecodeLabel block_end_;
 };
 
 
 // A class to help with co-ordinating break and continue statements with
 // their loop.
-class LoopBuilder final : public BreakableControlFlowBuilder {
+class V8_EXPORT_PRIVATE LoopBuilder final : public BreakableControlFlowBuilder {
  public:
   explicit LoopBuilder(BytecodeArrayBuilder* builder)
       : BreakableControlFlowBuilder(builder),
         continue_labels_(builder->zone()),
         header_labels_(builder->zone()) {}
   ~LoopBuilder();
 
-  void LoopHeader(ZoneVector<BytecodeLabel>* additional_labels);
+  void LoopHeader(ZoneVector<BytecodeLabel>* additional_labels = nullptr);
   void JumpToHeader(int loop_depth);
   void BindContinueTarget();
   void EndLoop();
 
   // This method is called when visiting continue statements in the AST.
   // Inserts a jump to an unbound label that is patched when BindContinueTarget
   // is called.
   void Continue() { EmitJump(&continue_labels_); }
   void ContinueIfTrue() { EmitJumpIfTrue(&continue_labels_); }
   void ContinueIfUndefined() { EmitJumpIfUndefined(&continue_labels_); }
   void ContinueIfNull() { EmitJumpIfNull(&continue_labels_); }
 
  private:
   BytecodeLabel loop_header_;
 
   // Unbound labels that identify jumps for continue statements in the code and
   // jumps from checking the loop condition to the header for do-while loops.
   BytecodeLabels continue_labels_;
   BytecodeLabels header_labels_;
 };
 
 
 // A class to help with co-ordinating break statements with their switch.
-class SwitchBuilder final : public BreakableControlFlowBuilder {
+class V8_EXPORT_PRIVATE SwitchBuilder final
+    : public BreakableControlFlowBuilder {
  public:
   explicit SwitchBuilder(BytecodeArrayBuilder* builder, int number_of_cases)
       : BreakableControlFlowBuilder(builder),
         case_sites_(builder->zone()) {
     case_sites_.resize(number_of_cases);
   }
   ~SwitchBuilder();
 
   // This method should be called by the SwitchBuilder owner when the case
   // statement with |index| is emitted to update the case jump site.
   void SetCaseTarget(int index);
 
   // This method is called when visiting case comparison operation for |index|.
   // Inserts a JumpIfTrue to a unbound label that is patched when the
   // corresponding SetCaseTarget is called.
   void Case(int index) { builder()->JumpIfTrue(&case_sites_.at(index)); }
 
   // This method is called when all cases comparisons have been emitted if there
   // is a default case statement. Inserts a Jump to a unbound label that is
   // patched when the corresponding SetCaseTarget is called.
   void DefaultAt(int index) { builder()->Jump(&case_sites_.at(index)); }
 
  private:
   // Unbound labels that identify jumps for case statements in the code.
   ZoneVector<BytecodeLabel> case_sites_;
 };
 
 
 // A class to help with co-ordinating control flow in try-catch statements.
-class TryCatchBuilder final : public ControlFlowBuilder {
+class V8_EXPORT_PRIVATE TryCatchBuilder final : public ControlFlowBuilder {
  public:
   explicit TryCatchBuilder(BytecodeArrayBuilder* builder,
                            HandlerTable::CatchPrediction catch_prediction)
       : ControlFlowBuilder(builder),
         handler_id_(builder->NewHandlerEntry()),
         catch_prediction_(catch_prediction) {}
 
   void BeginTry(Register context);
   void EndTry();
   void EndCatch();
 
  private:
   int handler_id_;
   HandlerTable::CatchPrediction catch_prediction_;
   BytecodeLabel handler_;
   BytecodeLabel exit_;
 };
 
 
 // A class to help with co-ordinating control flow in try-finally statements.
-class TryFinallyBuilder final : public ControlFlowBuilder {
+class V8_EXPORT_PRIVATE TryFinallyBuilder final : public ControlFlowBuilder {
  public:
   explicit TryFinallyBuilder(BytecodeArrayBuilder* builder,
                              HandlerTable::CatchPrediction catch_prediction)
       : ControlFlowBuilder(builder),
         handler_id_(builder->NewHandlerEntry()),
         catch_prediction_(catch_prediction),
         finalization_sites_(builder->zone()) {}
 
   void BeginTry(Register context);
   void LeaveTry();
   void EndTry();
   void BeginHandler();
   void BeginFinally();
   void EndFinally();
 
  private:
   int handler_id_;
   HandlerTable::CatchPrediction catch_prediction_;
   BytecodeLabel handler_;
 
   // Unbound labels that identify jumps to the finally block in the code.
   BytecodeLabels finalization_sites_;
 };
 
 }  // namespace interpreter
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_INTERPRETER_CONTROL_FLOW_BUILDERS_H_