[Interpreter] Ensure we always have an outer register allocation scope.

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 "src/ast/ast.h"
 #include "src/interpreter/bytecodes.h"
 #include "src/interpreter/constant-array-builder.h"
@@ skipping 316 matching lines @@
   bool exit_seen_in_block_;
   int unbound_jumps_;
 
   int parameter_count_;
   int local_register_count_;
   int context_register_count_;
   int temporary_register_count_;
   ZoneSet<int> free_temporaries_;
 
   class PreviousBytecodeHelper;
-  friend class TemporaryRegisterScope;
+  friend class BytecodeRegisterAllocator;
+
   DISALLOW_COPY_AND_ASSIGN(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:
@@ skipping 24 matching lines @@
   //                    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;
 };
 
-
-// A stack-allocated class than allows the instantiator to allocate
-// temporary registers that are cleaned up when scope is closed.
-// TODO(oth): Deprecate TemporaryRegisterScope use. Code should be
-// using result scopes as far as possible.
-class TemporaryRegisterScope {
- public:
-  explicit TemporaryRegisterScope(BytecodeArrayBuilder* builder);
-  ~TemporaryRegisterScope();
-  Register NewRegister();
-
-  void PrepareForConsecutiveAllocations(size_t count);
-  Register NextConsecutiveRegister();
-
-  bool RegisterIsAllocatedInThisScope(Register reg) const;
-
-  bool hasConsecutiveAllocations() const { return next_consecutive_count_ > 0; }
-
- private:
-  void* operator new(size_t size);
-  void operator delete(void* p);
-
-  BytecodeArrayBuilder* builder_;
-  const TemporaryRegisterScope* outer_;
-  ZoneVector<int> allocated_;
-  int next_consecutive_register_;
-  int next_consecutive_count_;
-
-  DISALLOW_COPY_AND_ASSIGN(TemporaryRegisterScope);
-};
-
-
 }  // namespace interpreter
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_INTERPRETER_BYTECODE_ARRAY_BUILDER_H_