[Interpreter] Local flow control in the bytecode graph builder.

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/zone-containers.h"
@@ skipping 26 matching lines @@
 
   // This method should be called by the control flow owner before
   // destruction to update sites that emit jumps for break.
   void SetBreakTarget(const BytecodeLabel& break_target);
 
   // This method is called when visiting break statements in the AST.
   // Inserts a jump to a unbound label that is patched when the corresponding
   // SetBreakTarget is called.
   void Break() { EmitJump(&break_sites_); }
   void BreakIfTrue() { EmitJumpIfTrue(&break_sites_); }
+  void BreakIfFalse() { EmitJumpIfFalse(&break_sites_); }
   void BreakIfUndefined() { EmitJumpIfUndefined(&break_sites_); }
   void BreakIfNull() { EmitJumpIfNull(&break_sites_); }
 
+

[Michael Starzinger, 2015/12/16 12:40:12]

nit: Stray empty newline.

[oth, 2015/12/16 14:17:06]

Done.

  protected:
   void EmitJump(ZoneVector<BytecodeLabel>* labels);
   void EmitJump(ZoneVector<BytecodeLabel>* labels, int index);
   void EmitJumpIfTrue(ZoneVector<BytecodeLabel>* labels);
   void EmitJumpIfTrue(ZoneVector<BytecodeLabel>* labels, int index);
+  void EmitJumpIfFalse(ZoneVector<BytecodeLabel>* labels);
+  void EmitJumpIfFalse(ZoneVector<BytecodeLabel>* labels, int index);
   void EmitJumpIfUndefined(ZoneVector<BytecodeLabel>* labels);
   void EmitJumpIfNull(ZoneVector<BytecodeLabel>* labels);
 
   void BindLabels(const BytecodeLabel& target, ZoneVector<BytecodeLabel>* site);
 
  private:
   // Unbound labels that identify jumps for break statements in the code.
   ZoneVector<BytecodeLabel> break_sites_;
 };
 
 // A class to help with co-ordinating break and continue statements with
 // their loop.
-// TODO(oth): add support for TF branch/merge info.
 class LoopBuilder final : public BreakableControlFlowBuilder {
  public:
   explicit LoopBuilder(BytecodeArrayBuilder* builder)
       : BreakableControlFlowBuilder(builder),
         continue_sites_(builder->zone()) {}
   ~LoopBuilder();
 
-  // This methods should be called by the LoopBuilder owner before
-  // destruction to update sites that emit jumps for continue.
-  void SetContinueTarget(const BytecodeLabel& continue_target);
+  void LoopHeader() { builder()->Bind(&loop_header_); }
+  void Condition() { builder()->Bind(&condition_); }
+  void Next() { builder()->Bind(&next_); }
+  void JumpToHeader() { builder()->Jump(&loop_header_); }
+  void JumpToHeaderIfTrue() { builder()->JumpIfTrue(&loop_header_); }
+  void LoopEnd();
 
   // This method is called when visiting continue statements in the AST.
   // Inserts a jump to a unbound label that is patched when the corresponding
   // SetContinueTarget is called.
   void Continue() { EmitJump(&continue_sites_); }
   void ContinueIfTrue() { EmitJumpIfTrue(&continue_sites_); }
   void ContinueIfUndefined() { EmitJumpIfUndefined(&continue_sites_); }
   void ContinueIfNull() { EmitJumpIfNull(&continue_sites_); }
 
  private:
+  void SetContinueTarget(const BytecodeLabel& continue_target);
+
+  BytecodeLabel loop_header_;
+  BytecodeLabel condition_;
+  BytecodeLabel next_;
+  BytecodeLabel loop_end_;
+
   // Unbound labels that identify jumps for continue statements in the code.
   ZoneVector<BytecodeLabel> continue_sites_;
 };
 
 // A class to help with co-ordinating break statements with their switch.
 // TODO(oth): add support for TF branch/merge info.
 class SwitchBuilder final : public BreakableControlFlowBuilder {
  public:
   explicit SwitchBuilder(BytecodeArrayBuilder* builder, int number_of_cases)
       : BreakableControlFlowBuilder(builder),
@@ skipping 19 matching lines @@
  private:
   // Unbound labels that identify jumps for case statements in the code.
   ZoneVector<BytecodeLabel> case_sites_;
 };
 
 }  // namespace interpreter
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_INTERPRETER_CONTROL_FLOW_BUILDERS_H_