[Interpreter] Add support for JS calls.

src/interpreter/interpreter.cc

 // 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.
 
 #include "src/interpreter/interpreter.h"
 
 #include "src/code-factory.h"
 #include "src/compiler.h"
 #include "src/compiler/interpreter-assembler.h"
 #include "src/factory.h"
@@ skipping 264 matching lines @@
 
 
 // Mod <src>
 //
 // Modulo register <src> by accumulator.
 void Interpreter::DoMod(compiler::InterpreterAssembler* assembler) {
   DoBinaryOp(Context::MOD_BUILTIN_INDEX, assembler);
 }
 
 
+// CallJS <first_arg_reg> <arg_count>
+//
+// Call a JS function with arguments in registers <first_arg_reg> to
+// <first_arg_reg + arg_count>. The JSfunction or Callable to call is in
+// the accumulator.
+void Interpreter::DoCallJS(compiler::InterpreterAssembler* assembler) {
+  Node* first_arg_reg_index = __ BytecodeOperandReg(0);
+  Node* first_arg = __ RegisterLocation(first_arg_reg_index);
+  Node* args_count = __ BytecodeOperandCount(1);
+  Node* args_size = __ WordShl(args_count, kPointerSizeLog2);
+  Node* last_arg = __ IntPtrSub(first_arg, args_size);
+  Node* function = __ GetAccumulator();
+  Node* result = __ CallJS(function, first_arg, last_arg);
+  __ SetAccumulator(result);
+  __ Dispatch();
+}
+
+
 // Return
 //
 // Return the value in register 0.
 void Interpreter::DoReturn(compiler::InterpreterAssembler* assembler) {
   __ Return();
 }
 
 
 }  // namespace interpreter
 }  // namespace internal
 }  // namespace v8