[Interpreter] Bytecodes for exchanging registers.

src/compiler/bytecode-graph-builder.h

Index: src/compiler/bytecode-graph-builder.h
diff --git a/src/compiler/bytecode-graph-builder.h b/src/compiler/bytecode-graph-builder.h
index a0b8699520f70383a86eafffd8f75e26d9177846..43b2d84c316c701f136626752a08babc2dd23c1e 100644
--- a/src/compiler/bytecode-graph-builder.h
+++ b/src/compiler/bytecode-graph-builder.h
@@ -267,6 +267,8 @@ class BytecodeGraphBuilder::Environment : public ZoneObject {
 
   void BindRegister(interpreter::Register the_register, Node* node);
   Node* LookupRegister(interpreter::Register the_register) const;
+  void ExchangeRegisters(interpreter::Register reg0,
+                         interpreter::Register reg1);
 
   void BindAccumulator(Node* node, FrameStateBeforeAndAfter* states = nullptr);
   Node* LookupAccumulator() const;