https://www.graalvm.org/ 
abstract class com.oracle.truffle.js.builtins.PolyglotBuiltins$PolyglotUnboxValueNode extends com.oracle.truffle.js.nodes.function.JSBuiltinNode
  minor version: 0
  major version: 59
  flags: flags: (0x0420) ACC_SUPER, ACC_ABSTRACT
  this_class: com.oracle.truffle.js.builtins.PolyglotBuiltins$PolyglotUnboxValueNode
  super_class: com.oracle.truffle.js.nodes.function.JSBuiltinNode
{
  void <init>(com.oracle.truffle.js.runtime.JSContext, com.oracle.truffle.js.nodes.function.JSBuiltin);
    descriptor: (Lcom/oracle/truffle/js/runtime/JSContext;Lcom/oracle/truffle/js/nodes/function/JSBuiltin;)V
    flags: (0x0000) 
    Code:
      stack=3, locals=3, args_size=3
        start local 0 // com.oracle.truffle.js.builtins.PolyglotBuiltins$PolyglotUnboxValueNode this
        start local 1 // com.oracle.truffle.js.runtime.JSContext context
        start local 2 // com.oracle.truffle.js.nodes.function.JSBuiltin builtin
         0: .line 616
            aload 0 /* this */
            aload 1 /* context */
            aload 2 /* builtin */
            invokespecial com.oracle.truffle.js.nodes.function.JSBuiltinNode.<init>:(Lcom/oracle/truffle/js/runtime/JSContext;Lcom/oracle/truffle/js/nodes/function/JSBuiltin;)V
         1: .line 617
            return
        end local 2 // com.oracle.truffle.js.nodes.function.JSBuiltin builtin
        end local 1 // com.oracle.truffle.js.runtime.JSContext context
        end local 0 // com.oracle.truffle.js.builtins.PolyglotBuiltins$PolyglotUnboxValueNode this
      LocalVariableTable:
        Start  End  Slot     Name  Signature
            0    2     0     this  Lcom/oracle/truffle/js/builtins/PolyglotBuiltins$PolyglotUnboxValueNode;
            0    2     1  context  Lcom/oracle/truffle/js/runtime/JSContext;
            0    2     2  builtin  Lcom/oracle/truffle/js/nodes/function/JSBuiltin;
    MethodParameters:
         Name  Flags
      context  
      builtin  

  protected java.lang.Object truffleObject(com.oracle.truffle.api.interop.TruffleObject, com.oracle.truffle.api.interop.InteropLibrary);
    descriptor: (Lcom/oracle/truffle/api/interop/TruffleObject;Lcom/oracle/truffle/api/interop/InteropLibrary;)Ljava/lang/Object;
    flags: (0x0004) ACC_PROTECTED
    Code:
      stack=4, locals=4, args_size=3
        start local 0 // com.oracle.truffle.js.builtins.PolyglotBuiltins$PolyglotUnboxValueNode this
        start local 1 // com.oracle.truffle.api.interop.TruffleObject obj
        start local 2 // com.oracle.truffle.api.interop.InteropLibrary interop
         0: .line 622
            aload 1 /* obj */
            aload 1 /* obj */
            aload 2 /* interop */
            aload 0 /* this */
            invokestatic com.oracle.truffle.js.runtime.interop.JSInteropUtil.toPrimitiveOrDefault:(Ljava/lang/Object;Ljava/lang/Object;Lcom/oracle/truffle/api/interop/InteropLibrary;Lcom/oracle/truffle/api/nodes/Node;)Ljava/lang/Object;
            astore 3 /* unboxed */
        start local 3 // java.lang.Object unboxed
         1: .line 623
            aload 3 /* unboxed */
            aload 1 /* obj */
            if_acmpne 3
         2: .line 624
            ldc "unbox"
            invokestatic com.oracle.truffle.js.runtime.Errors.createTypeErrorNotATruffleObject:(Ljava/lang/String;)Lcom/oracle/truffle/js/runtime/JSException;
            athrow
         3: .line 626
      StackMap locals: java.lang.Object
      StackMap stack:
            aload 3 /* unboxed */
            areturn
        end local 3 // java.lang.Object unboxed
        end local 2 // com.oracle.truffle.api.interop.InteropLibrary interop
        end local 1 // com.oracle.truffle.api.interop.TruffleObject obj
        end local 0 // com.oracle.truffle.js.builtins.PolyglotBuiltins$PolyglotUnboxValueNode this
      LocalVariableTable:
        Start  End  Slot     Name  Signature
            0    4     0     this  Lcom/oracle/truffle/js/builtins/PolyglotBuiltins$PolyglotUnboxValueNode;
            0    4     1      obj  Lcom/oracle/truffle/api/interop/TruffleObject;
            0    4     2  interop  Lcom/oracle/truffle/api/interop/InteropLibrary;
            1    4     3  unboxed  Ljava/lang/Object;
    RuntimeVisibleAnnotations: 
      com.oracle.truffle.api.dsl.Specialization()
    RuntimeInvisibleParameterAnnotations: 
      0:
      1:
        com.oracle.truffle.api.library.CachedLibrary(limit = "InteropLibraryLimit")
    MethodParameters:
         Name  Flags
      obj      
      interop  

  protected java.lang.Object primitive(java.lang.Object);
    descriptor: (Ljava/lang/Object;)Ljava/lang/Object;
    flags: (0x0004) ACC_PROTECTED
    Code:
      stack=1, locals=2, args_size=2
        start local 0 // com.oracle.truffle.js.builtins.PolyglotBuiltins$PolyglotUnboxValueNode this
        start local 1 // java.lang.Object obj
         0: .line 632
            aload 1 /* obj */
            areturn
        end local 1 // java.lang.Object obj
        end local 0 // com.oracle.truffle.js.builtins.PolyglotBuiltins$PolyglotUnboxValueNode this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lcom/oracle/truffle/js/builtins/PolyglotBuiltins$PolyglotUnboxValueNode;
            0    1     1   obj  Ljava/lang/Object;
    RuntimeVisibleAnnotations: 
      com.oracle.truffle.api.dsl.Specialization(guards = {"isJavaPrimitive(obj)"})
    MethodParameters:
      Name  Flags
      obj   

  protected boolean unsupported(java.lang.Object);
    descriptor: (Ljava/lang/Object;)Z
    flags: (0x0004) ACC_PROTECTED
    Code:
      stack=1, locals=2, args_size=2
        start local 0 // com.oracle.truffle.js.builtins.PolyglotBuiltins$PolyglotUnboxValueNode this
        start local 1 // java.lang.Object obj
         0: .line 638
            ldc "unbox"
            invokestatic com.oracle.truffle.js.runtime.Errors.createTypeErrorNotATruffleObject:(Ljava/lang/String;)Lcom/oracle/truffle/js/runtime/JSException;
            athrow
        end local 1 // java.lang.Object obj
        end local 0 // com.oracle.truffle.js.builtins.PolyglotBuiltins$PolyglotUnboxValueNode this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lcom/oracle/truffle/js/builtins/PolyglotBuiltins$PolyglotUnboxValueNode;
            0    1     1   obj  Ljava/lang/Object;
    RuntimeVisibleAnnotations: 
      com.oracle.truffle.api.dsl.Specialization(guards = {"!isTruffleObject(obj)", "!isJavaPrimitive(obj)"})
    MethodParameters:
      Name  Flags
      obj   
}
SourceFile: "PolyglotBuiltins.java"
NestHost: com.oracle.truffle.js.builtins.PolyglotBuiltins
InnerClasses:
  abstract PolyglotUnboxValueNode = com.oracle.truffle.js.builtins.PolyglotBuiltins$PolyglotUnboxValueNode of com.oracle.truffle.js.builtins.PolyglotBuiltins
    RuntimeInvisibleAnnotations: 
      com.oracle.truffle.api.dsl.ImportStatic(value = {Lcom/oracle/truffle/js/runtime/JSConfig;})