[Interpreter] Add for/while/do support to the bytecode generator.

src/interpreter/bytecode-array-builder.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_BYTECODE_ARRAY_BUILDER_H_
 #define V8_INTERPRETER_BYTECODE_ARRAY_BUILDER_H_
 
 #include <vector>
 
 #include "src/ast.h"
@@ skipping 69 matching lines @@
 
   // Tests.
   BytecodeArrayBuilder& CompareOperation(Token::Value op, Register reg,
                                          LanguageMode language_mode);
 
   // Casts
   BytecodeArrayBuilder& CastAccumulatorToBoolean();
 
   // Flow Control.
   BytecodeArrayBuilder& Bind(BytecodeLabel* label);
+  BytecodeArrayBuilder& Bind(BytecodeLabel* unbound,
+                             const BytecodeLabel* const bound);

[rmcilroy, 2015/10/01 12:12:07]

const ref instead? Also, the names still confuse me. How about:
  BytecodeArrayBuilder& Bind(BytecodeLabel* label,
                             const BytecodeLabel& target);

?

[oth, 2015/10/01 13:13:56]

As discussed, changed to:

BytecodeArrayBuilder::Bind(
const BytecodeLabel& target, BytecodeLabel* label) {                            
                                                                                
                                                                                
                         

   BytecodeArrayBuilder& Jump(BytecodeLabel* label);
   BytecodeArrayBuilder& JumpIfTrue(BytecodeLabel* label);
   BytecodeArrayBuilder& JumpIfFalse(BytecodeLabel* label);
   BytecodeArrayBuilder& Return();
 
   BytecodeArrayBuilder& EnterBlock();
   BytecodeArrayBuilder& LeaveBlock();
 
+  // Accessors
+  Zone* zone() const { return zone_; }
+
  private:
   ZoneVector<uint8_t>* bytecodes() { return &bytecodes_; }
   const ZoneVector<uint8_t>* bytecodes() const { return &bytecodes_; }
   Isolate* isolate() const { return isolate_; }
 
   static Bytecode BytecodeForBinaryOperation(Token::Value op);
   static Bytecode BytecodeForCompareOperation(Token::Value op);
   static bool FitsInIdxOperand(int value);
   static bool FitsInIdxOperand(size_t value);
   static bool FitsInImm8Operand(int value);
@@ skipping 18 matching lines @@
                       uint8_t operand_value) const;
   bool LastBytecodeInSameBlock() const;
 
   size_t GetConstantPoolEntry(Handle<Object> object);
 
   // Scope helpers used by TemporaryRegisterScope
   int BorrowTemporaryRegister();
   void ReturnTemporaryRegister(int reg_index);
 
   Isolate* isolate_;
+  Zone* zone_;
   ZoneVector<uint8_t> bytecodes_;
   bool bytecode_generated_;
   size_t last_block_end_;
   size_t last_bytecode_start_;
   bool return_seen_in_block_;
 
   IdentityMap<size_t> constants_map_;
   ZoneVector<Handle<Object>> constants_;
 
   int parameter_count_;
   int local_register_count_;
   int temporary_register_count_;
   int temporary_register_next_;
 
   friend class TemporaryRegisterScope;
   DISALLOW_IMPLICIT_CONSTRUCTORS(BytecodeArrayBuilder);
 };
 
 
 // A label representing a branch target in a bytecode array. When a
 // label is bound, it represents a known position in the bytecode
 // array. For labels that are forward references there can be at most
 // one reference whilst it is unbound.
 class BytecodeLabel final {
  public:
   BytecodeLabel() : bound_(false), offset_(kInvalidOffset) {}
-  ~BytecodeLabel() { DCHECK(bound_ && offset_ != kInvalidOffset); }
 
  private:
   static const size_t kInvalidOffset = static_cast<size_t>(-1);
 
   INLINE(void bind_to(size_t offset)) {
     DCHECK(!bound_ && offset != kInvalidOffset);
     offset_ = offset;
     bound_ = true;
   }
   INLINE(void set_referrer(size_t offset)) {
     DCHECK(!bound_ && offset != kInvalidOffset);
     offset_ = offset;
   }
   INLINE(size_t offset() const) { return offset_; }
   INLINE(bool is_bound() const) { return bound_; }
   INLINE(bool is_forward_target() const) {
     return offset() != kInvalidOffset && !is_bound();
   }
 
   // There are three states for a label:
   //                    bound_   offset_
   //  UNSET             false    kInvalidOffset
   //  FORWARD_TARGET    false    Offset of referring jump
   //  BACKWARD_TARGET    true    Offset of label in bytecode array when bound
   bool bound_;
   size_t offset_;
 
   friend class BytecodeArrayBuilder;
-  DISALLOW_COPY_AND_ASSIGN(BytecodeLabel);
 };
 
 
 // A stack-allocated class than allows the instantiator to allocate
 // temporary registers that are cleaned up when scope is closed.
 class TemporaryRegisterScope {
  public:
   explicit TemporaryRegisterScope(BytecodeArrayBuilder* builder);
   ~TemporaryRegisterScope();
   Register NewRegister();
 
  private:
   void* operator new(size_t size);
   void operator delete(void* p);
 
   BytecodeArrayBuilder* builder_;
   int count_;
   int last_register_index_;
 
   DISALLOW_COPY_AND_ASSIGN(TemporaryRegisterScope);
 };
 
 
 }  // namespace interpreter
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_INTERPRETER_BYTECODE_ARRAY_BUILDER_H_