https://www.graalvm.org/ 
public class org.graalvm.compiler.nodes.PiNode$Placeholder extends org.graalvm.compiler.nodes.FloatingGuardedNode
  minor version: 0
  major version: 59
  flags: flags: (0x0021) ACC_PUBLIC, ACC_SUPER
  this_class: org.graalvm.compiler.nodes.PiNode$Placeholder
  super_class: org.graalvm.compiler.nodes.FloatingGuardedNode
{
  public static final org.graalvm.compiler.graph.NodeClass<org.graalvm.compiler.nodes.PiNode$Placeholder> TYPE;
    descriptor: Lorg/graalvm/compiler/graph/NodeClass;
    flags: (0x0019) ACC_PUBLIC, ACC_STATIC, ACC_FINAL
    Signature: Lorg/graalvm/compiler/graph/NodeClass<Lorg/graalvm/compiler/nodes/PiNode$Placeholder;>;

  org.graalvm.compiler.nodes.ValueNode object;
    descriptor: Lorg/graalvm/compiler/nodes/ValueNode;
    flags: (0x0000) 
    RuntimeVisibleAnnotations: 
      org.graalvm.compiler.graph.Node$Input()

  static void <clinit>();
    descriptor: ()V
    flags: (0x0008) ACC_STATIC
    Code:
      stack=1, locals=0, args_size=0
         0: .line 304
            ldc Lorg/graalvm/compiler/nodes/PiNode$Placeholder;
            invokestatic org.graalvm.compiler.graph.NodeClass.create:(Ljava/lang/Class;)Lorg/graalvm/compiler/graph/NodeClass;
            putstatic org.graalvm.compiler.nodes.PiNode$Placeholder.TYPE:Lorg/graalvm/compiler/graph/NodeClass;
            return
      LocalVariableTable:
        Start  End  Slot  Name  Signature

  public org.graalvm.compiler.nodes.ValueNode object();
    descriptor: ()Lorg/graalvm/compiler/nodes/ValueNode;
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=1, locals=1, args_size=1
        start local 0 // org.graalvm.compiler.nodes.PiNode$Placeholder this
         0: .line 308
            aload 0 /* this */
            getfield org.graalvm.compiler.nodes.PiNode$Placeholder.object:Lorg/graalvm/compiler/nodes/ValueNode;
            areturn
        end local 0 // org.graalvm.compiler.nodes.PiNode$Placeholder this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lorg/graalvm/compiler/nodes/PiNode$Placeholder;

  protected void <init>(org.graalvm.compiler.graph.NodeClass<? extends org.graalvm.compiler.nodes.PiNode$Placeholder>, org.graalvm.compiler.nodes.ValueNode);
    descriptor: (Lorg/graalvm/compiler/graph/NodeClass;Lorg/graalvm/compiler/nodes/ValueNode;)V
    flags: (0x0004) ACC_PROTECTED
    Code:
      stack=4, locals=3, args_size=3
        start local 0 // org.graalvm.compiler.nodes.PiNode$Placeholder this
        start local 1 // org.graalvm.compiler.graph.NodeClass c
        start local 2 // org.graalvm.compiler.nodes.ValueNode object
         0: .line 312
            aload 0 /* this */
            aload 1 /* c */
            getstatic org.graalvm.compiler.nodes.PiNode$PlaceholderStamp.SINGLETON:Lorg/graalvm/compiler/nodes/PiNode$PlaceholderStamp;
            aconst_null
            invokespecial org.graalvm.compiler.nodes.FloatingGuardedNode.<init>:(Lorg/graalvm/compiler/graph/NodeClass;Lorg/graalvm/compiler/core/common/type/Stamp;Lorg/graalvm/compiler/nodes/extended/GuardingNode;)V
         1: .line 313
            aload 0 /* this */
            aload 2 /* object */
            putfield org.graalvm.compiler.nodes.PiNode$Placeholder.object:Lorg/graalvm/compiler/nodes/ValueNode;
         2: .line 314
            return
        end local 2 // org.graalvm.compiler.nodes.ValueNode object
        end local 1 // org.graalvm.compiler.graph.NodeClass c
        end local 0 // org.graalvm.compiler.nodes.PiNode$Placeholder this
      LocalVariableTable:
        Start  End  Slot    Name  Signature
            0    3     0    this  Lorg/graalvm/compiler/nodes/PiNode$Placeholder;
            0    3     1       c  Lorg/graalvm/compiler/graph/NodeClass<+Lorg/graalvm/compiler/nodes/PiNode$Placeholder;>;
            0    3     2  object  Lorg/graalvm/compiler/nodes/ValueNode;
    Signature: (Lorg/graalvm/compiler/graph/NodeClass<+Lorg/graalvm/compiler/nodes/PiNode$Placeholder;>;Lorg/graalvm/compiler/nodes/ValueNode;)V
    MethodParameters:
        Name  Flags
      c       
      object  

  public void <init>(org.graalvm.compiler.nodes.ValueNode);
    descriptor: (Lorg/graalvm/compiler/nodes/ValueNode;)V
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=3, locals=2, args_size=2
        start local 0 // org.graalvm.compiler.nodes.PiNode$Placeholder this
        start local 1 // org.graalvm.compiler.nodes.ValueNode object
         0: .line 317
            aload 0 /* this */
            getstatic org.graalvm.compiler.nodes.PiNode$Placeholder.TYPE:Lorg/graalvm/compiler/graph/NodeClass;
            aload 1 /* object */
            invokespecial org.graalvm.compiler.nodes.PiNode$Placeholder.<init>:(Lorg/graalvm/compiler/graph/NodeClass;Lorg/graalvm/compiler/nodes/ValueNode;)V
         1: .line 318
            return
        end local 1 // org.graalvm.compiler.nodes.ValueNode object
        end local 0 // org.graalvm.compiler.nodes.PiNode$Placeholder this
      LocalVariableTable:
        Start  End  Slot    Name  Signature
            0    2     0    this  Lorg/graalvm/compiler/nodes/PiNode$Placeholder;
            0    2     1  object  Lorg/graalvm/compiler/nodes/ValueNode;
    MethodParameters:
        Name  Flags
      object  

  public void makeReplacement(org.graalvm.compiler.core.common.type.Stamp);
    descriptor: (Lorg/graalvm/compiler/core/common/type/Stamp;)V
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=4, locals=3, args_size=2
        start local 0 // org.graalvm.compiler.nodes.PiNode$Placeholder this
        start local 1 // org.graalvm.compiler.core.common.type.Stamp snippetReplaceeStamp
         0: .line 326
            aload 0 /* this */
            invokevirtual org.graalvm.compiler.nodes.PiNode$Placeholder.graph:()Lorg/graalvm/compiler/nodes/StructuredGraph;
            aload 0 /* this */
            invokevirtual org.graalvm.compiler.nodes.PiNode$Placeholder.object:()Lorg/graalvm/compiler/nodes/ValueNode;
            aload 1 /* snippetReplaceeStamp */
            aconst_null
            invokestatic org.graalvm.compiler.nodes.PiNode.create:(Lorg/graalvm/compiler/nodes/ValueNode;Lorg/graalvm/compiler/core/common/type/Stamp;Lorg/graalvm/compiler/nodes/ValueNode;)Lorg/graalvm/compiler/nodes/ValueNode;
            invokevirtual org.graalvm.compiler.nodes.StructuredGraph.maybeAddOrUnique:(Lorg/graalvm/compiler/graph/Node;)Lorg/graalvm/compiler/graph/Node;
            checkcast org.graalvm.compiler.nodes.ValueNode
            astore 2 /* value */
        start local 2 // org.graalvm.compiler.nodes.ValueNode value
         1: .line 327
            aload 0 /* this */
            aload 2 /* value */
            invokevirtual org.graalvm.compiler.nodes.PiNode$Placeholder.replaceAndDelete:(Lorg/graalvm/compiler/graph/Node;)V
         2: .line 328
            return
        end local 2 // org.graalvm.compiler.nodes.ValueNode value
        end local 1 // org.graalvm.compiler.core.common.type.Stamp snippetReplaceeStamp
        end local 0 // org.graalvm.compiler.nodes.PiNode$Placeholder this
      LocalVariableTable:
        Start  End  Slot                  Name  Signature
            0    3     0                  this  Lorg/graalvm/compiler/nodes/PiNode$Placeholder;
            0    3     1  snippetReplaceeStamp  Lorg/graalvm/compiler/core/common/type/Stamp;
            1    3     2                 value  Lorg/graalvm/compiler/nodes/ValueNode;
    MethodParameters:
                      Name  Flags
      snippetReplaceeStamp  
}
SourceFile: "PiNode.java"
NestHost: org.graalvm.compiler.nodes.PiNode
InnerClasses:
  public abstract Input = org.graalvm.compiler.graph.Node$Input of org.graalvm.compiler.graph.Node
  public Placeholder = org.graalvm.compiler.nodes.PiNode$Placeholder of org.graalvm.compiler.nodes.PiNode
  public final PlaceholderStamp = org.graalvm.compiler.nodes.PiNode$PlaceholderStamp of org.graalvm.compiler.nodes.PiNode
    RuntimeVisibleAnnotations: 
      org.graalvm.compiler.nodeinfo.NodeInfo(cycles = org.graalvm.compiler.nodeinfo.NodeCycles.CYCLES_0:Lorg/graalvm/compiler/nodeinfo/NodeCycles;, size = org.graalvm.compiler.nodeinfo.NodeSize.SIZE_0:Lorg/graalvm/compiler/nodeinfo/NodeSize;)