Packages

trait DynamicConstantRewriting extends DeferredDynamicConstantResolution with BootstrapArgumentLoading

Provides support for rewriting Java 11 dynamic constant loading instructions. This trait should be mixed in alongside a BytecodeReaderAndBinding, which extracts basic dynamic constant information from the BootstrapMethodTable.

Specifically, whenever an ldc, ldc_w or ldc2_w instruction is encountered that loads a dynamic constant, this trait tries to rewrite it to a simpler expression providing the same constant or an invocation of a method providing the constant from a lazily-initialized field.

Self Type
DynamicConstantRewriting with ClassFileBinding
Source
DynamicConstantRewriting.scala
Note

This rewriting is best-effort only. As ldc instructions take only two bytes, they cannot easily be rewritten to invocations, etc. ldc_w and ldc2_w instructions, however, are rewritten more aggressively.

See also

Hands on Java 11's constantdynamic for further information.

Linear Supertypes
BootstrapArgumentLoading, DeferredDynamicConstantResolution, CodeBinding, ConstantPoolBinding, Constant_PoolReader, Constant_PoolAbstractions, AnyRef, Any
Known Subclasses
Java11FrameworkWithDynamicRewritingAndCaching, Java16FrameworkWithDynamicRewritingAndCaching, Java17FrameworkWithDynamicRewritingAndCaching
Ordering
  1. Alphabetic
  2. By Inheritance
Inherited
  1. DynamicConstantRewriting
  2. BootstrapArgumentLoading
  3. DeferredDynamicConstantResolution
  4. CodeBinding
  5. ConstantPoolBinding
  6. Constant_PoolReader
  7. Constant_PoolAbstractions
  8. AnyRef
  9. Any
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Visibility
  1. Public
  2. Protected

Type Members

  1. type CONSTANT_Class_info = cp.CONSTANT_Class_info
    Definition Classes
    ConstantPoolBinding → Constant_PoolReader
  2. type CONSTANT_Double_info = cp.CONSTANT_Double_info
    Definition Classes
    ConstantPoolBinding → Constant_PoolReader
  3. type CONSTANT_Dynamic_info = cp.CONSTANT_Dynamic_info
    Definition Classes
    ConstantPoolBinding → Constant_PoolReader
  4. type CONSTANT_Fieldref_info = cp.CONSTANT_Fieldref_info
    Definition Classes
    ConstantPoolBinding → Constant_PoolReader
  5. type CONSTANT_Float_info = cp.CONSTANT_Float_info
    Definition Classes
    ConstantPoolBinding → Constant_PoolReader
  6. type CONSTANT_Integer_info = cp.CONSTANT_Integer_info
    Definition Classes
    ConstantPoolBinding → Constant_PoolReader
  7. type CONSTANT_InterfaceMethodref_info = cp.CONSTANT_InterfaceMethodref_info
    Definition Classes
    ConstantPoolBinding → Constant_PoolReader
  8. type CONSTANT_InvokeDynamic_info = cp.CONSTANT_InvokeDynamic_info
    Definition Classes
    ConstantPoolBinding → Constant_PoolReader
  9. type CONSTANT_Long_info = cp.CONSTANT_Long_info
    Definition Classes
    ConstantPoolBinding → Constant_PoolReader
  10. type CONSTANT_MethodHandle_info = cp.CONSTANT_MethodHandle_info
    Definition Classes
    ConstantPoolBinding → Constant_PoolReader
  11. type CONSTANT_MethodType_info = cp.CONSTANT_MethodType_info
    Definition Classes
    ConstantPoolBinding → Constant_PoolReader
  12. type CONSTANT_Methodref_info = cp.CONSTANT_Methodref_info
    Definition Classes
    ConstantPoolBinding → Constant_PoolReader
  13. type CONSTANT_Module_info = cp.CONSTANT_Module_info
    Definition Classes
    ConstantPoolBinding → Constant_PoolReader
  14. type CONSTANT_NameAndType_info = cp.CONSTANT_NameAndType_info
    Definition Classes
    ConstantPoolBinding → Constant_PoolReader
  15. type CONSTANT_Package_info = cp.CONSTANT_Package_info
    Definition Classes
    ConstantPoolBinding → Constant_PoolReader
  16. type CONSTANT_String_info = cp.CONSTANT_String_info
    Definition Classes
    ConstantPoolBinding → Constant_PoolReader
  17. type CONSTANT_Utf8_info = cp.CONSTANT_Utf8_info
    Definition Classes
    ConstantPoolBinding → Constant_PoolReader → Constant_PoolAbstractions
  18. abstract type ClassFile <: br.ClassFile
    Definition Classes
    ConstantPoolBinding → Constant_PoolAbstractions
  19. final type Constant_Pool = Array[(DynamicConstantRewriting.this)#Constant_Pool_Entry]
    Definition Classes
    Constant_PoolAbstractions
  20. type Constant_Pool_Entry = cp.Constant_Pool_Entry
    Definition Classes
    ConstantPoolBinding → Constant_PoolAbstractions
  21. final type Constant_Pool_Index = Int
    Definition Classes
    Constant_PoolAbstractions
  22. type DeferredActionsStore = Buffer[((DynamicConstantRewriting.this)#ClassFile) => (DynamicConstantRewriting.this)#ClassFile] with (DynamicConstantRewriting.this)#Constant_Pool_Entry

    A DeferredActionsStore stores all functions that need to perform post load actions.

    A DeferredActionsStore stores all functions that need to perform post load actions.

    One example is the resolution of references to attributes. (The constant pool is the only structure that is passed around and hence it is the only place where to store information/functions related to a specific class file).

    Definition Classes
    Constant_PoolAbstractions
  23. type Instructions = Array[Instruction]
    Definition Classes
    CodeBinding

Value Members

  1. def CONSTANT_Class_info(i: Int): (DynamicConstantRewriting.this)#CONSTANT_Class_info
    Definition Classes
    ConstantPoolBinding → Constant_PoolReader
  2. def CONSTANT_Double_info(d: Double): (DynamicConstantRewriting.this)#CONSTANT_Double_info
    Definition Classes
    ConstantPoolBinding → Constant_PoolReader
  3. def CONSTANT_Dynamic_info(bootstrap_method_attr_index: (DynamicConstantRewriting.this)#Constant_Pool_Index, name_and_type_index: (DynamicConstantRewriting.this)#Constant_Pool_Index): (DynamicConstantRewriting.this)#CONSTANT_Dynamic_info
    Definition Classes
    ConstantPoolBinding → Constant_PoolReader
  4. def CONSTANT_Fieldref_info(class_index: (DynamicConstantRewriting.this)#Constant_Pool_Index, name_and_type_index: (DynamicConstantRewriting.this)#Constant_Pool_Index): (DynamicConstantRewriting.this)#CONSTANT_Fieldref_info
    Definition Classes
    ConstantPoolBinding → Constant_PoolReader
  5. def CONSTANT_Float_info(f: Float): (DynamicConstantRewriting.this)#CONSTANT_Float_info
    Definition Classes
    ConstantPoolBinding → Constant_PoolReader
  6. def CONSTANT_Integer_info(i: Int): (DynamicConstantRewriting.this)#CONSTANT_Integer_info
    Definition Classes
    ConstantPoolBinding → Constant_PoolReader
  7. def CONSTANT_InterfaceMethodref_info(class_index: (DynamicConstantRewriting.this)#Constant_Pool_Index, name_and_type_index: (DynamicConstantRewriting.this)#Constant_Pool_Index): (DynamicConstantRewriting.this)#CONSTANT_InterfaceMethodref_info
    Definition Classes
    ConstantPoolBinding → Constant_PoolReader
  8. def CONSTANT_InvokeDynamic_info(bootstrap_method_attr_index: (DynamicConstantRewriting.this)#Constant_Pool_Index, name_and_type_index: (DynamicConstantRewriting.this)#Constant_Pool_Index): (DynamicConstantRewriting.this)#CONSTANT_InvokeDynamic_info
    Definition Classes
    ConstantPoolBinding → Constant_PoolReader
  9. def CONSTANT_Long_info(l: Long): (DynamicConstantRewriting.this)#CONSTANT_Long_info
    Definition Classes
    ConstantPoolBinding → Constant_PoolReader
  10. def CONSTANT_MethodHandle_info(reference_kind: Int, reference_index: Int): (DynamicConstantRewriting.this)#CONSTANT_MethodHandle_info
    Definition Classes
    ConstantPoolBinding → Constant_PoolReader
  11. def CONSTANT_MethodType_info(descriptor_index: (DynamicConstantRewriting.this)#Constant_Pool_Index): (DynamicConstantRewriting.this)#CONSTANT_MethodType_info
    Definition Classes
    ConstantPoolBinding → Constant_PoolReader
  12. def CONSTANT_Methodref_info(class_index: (DynamicConstantRewriting.this)#Constant_Pool_Index, name_and_type_index: (DynamicConstantRewriting.this)#Constant_Pool_Index): (DynamicConstantRewriting.this)#CONSTANT_Methodref_info
    Definition Classes
    ConstantPoolBinding → Constant_PoolReader
  13. def CONSTANT_Module_info(name_index: (DynamicConstantRewriting.this)#Constant_Pool_Index): (DynamicConstantRewriting.this)#CONSTANT_Module_info
    Definition Classes
    ConstantPoolBinding → Constant_PoolReader
  14. def CONSTANT_NameAndType_info(name_index: (DynamicConstantRewriting.this)#Constant_Pool_Index, descriptor_index: (DynamicConstantRewriting.this)#Constant_Pool_Index): (DynamicConstantRewriting.this)#CONSTANT_NameAndType_info
    Definition Classes
    ConstantPoolBinding → Constant_PoolReader
  15. def CONSTANT_Package_info(name_index: (DynamicConstantRewriting.this)#Constant_Pool_Index): (DynamicConstantRewriting.this)#CONSTANT_Package_info
    Definition Classes
    ConstantPoolBinding → Constant_PoolReader
  16. def CONSTANT_String_info(i: Int): (DynamicConstantRewriting.this)#CONSTANT_String_info
    Definition Classes
    ConstantPoolBinding → Constant_PoolReader
  17. def CONSTANT_Utf8_info(r: Array[Byte], s: String): (DynamicConstantRewriting.this)#CONSTANT_Utf8_info
    Definition Classes
    ConstantPoolBinding → Constant_PoolReader
  18. def Constant_Pool(in: DataInputStream): (DynamicConstantRewriting.this)#Constant_Pool
    Definition Classes
    Constant_PoolReader
  19. def applyDeferredActions(cp: (DynamicConstantRewriting.this)#Constant_Pool, classFile: (DynamicConstantRewriting.this)#ClassFile): (DynamicConstantRewriting.this)#ClassFile

    This method is called/needs to be called after the class file was completely loaded to perform class file specific transformations.

    This method is called/needs to be called after the class file was completely loaded to perform class file specific transformations.

    Definition Classes
    Constant_PoolReader → Constant_PoolAbstractions
  20. implicit val constantPoolEntryType: ClassTag[cp.Constant_Pool_Entry]
    Definition Classes
    ConstantPoolBinding → Constant_PoolAbstractions
  21. implicit def cpIndexTocpEntry(index: (DynamicConstantRewriting.this)#Constant_Pool_Index)(implicit cp: (DynamicConstantRewriting.this)#Constant_Pool): (DynamicConstantRewriting.this)#Constant_Pool_Entry
    Definition Classes
    ConstantPoolBinding
  22. def deferredDynamicConstantResolution(classFile: (DynamicConstantRewriting.this)#ClassFile, cp: (DynamicConstantRewriting.this)#Constant_Pool, methodNameIndex: (DynamicConstantRewriting.this)#Constant_Pool_Index, methodDescriptorIndex: (DynamicConstantRewriting.this)#Constant_Pool_Index, dynamicInfo: (DynamicConstantRewriting.this)#CONSTANT_Dynamic_info, instructions: Array[Instruction], pc: PC): (DynamicConstantRewriting.this)#ClassFile

    Resolves an org.opalj.br.instructions.INCOMPLETE_LDC instruction using the BootstrapMethodTable of the class.

    Resolves an org.opalj.br.instructions.INCOMPLETE_LDC instruction using the BootstrapMethodTable of the class.

    Deferred resolution is necessary since the BootstrapMethodTable – which is an attribute of the class file – is loaded after the methods.

    classFile

    The ClassFile with which the deferred action was registered.

    cp

    The class file's Constant_Pool.

    dynamicInfo

    The consttant pool entry describing the dynamic constant.

    instructions

    This method's array of instructions.Instructions. (The array returned by the #Instructions method.)

    pc

    The program counter of the invokedynamic instruction.

    Definition Classes
    DynamicConstantRewriting → DeferredDynamicConstantResolution
    Note

    This method is called (back) after the class file was completely loaded. Registration as a callback method happens whenever an ldc instruction is found in a method's byte code that refers to a dynamic constant.

    Overriding this Method

    To perform additional analyses on dynamic constant loading ldc instructions, e.g., to fully resolve the constant, a subclass may override this method to do so. When you override this method, you should call this method (super.deferredResolveDynamicConstantResolution) to ensure that the default resolution is carried out.

  23. def loadBootstrapArgument(argument: ConstantValue[_], instructions: InstructionsBuilder, classFile: br.ClassFile, boxed: Boolean = false): (Int, br.ClassFile)

    Generate instructions to load a constant argument for a bootstrap method.

    Generate instructions to load a constant argument for a bootstrap method.

    argument

    The argument to be loaded

    instructions

    The instruction builder the instructions are appended to

    classFile

    The class file the constant is in

    boxed

    If true, ensures the argument is of a reference type, boxing it if necessary

    returns

    The maximum stack height the generated instructions require and the (potentially new!) class file

    Definition Classes
    BootstrapArgumentLoading
  24. def loadDynamicConstant(bootstrapMethod: BootstrapMethod, name: String, descriptor: FieldType, instructions: InstructionsBuilder, classFile: br.ClassFile, boxed: Boolean = false): (Int, br.ClassFile)

    Generate instructions to load a dynamic constant.

    Generate instructions to load a dynamic constant.

    bootstrapMethod

    The constant's bootstrap method

    name

    The constant's name information, passed as the bootstrap method's 2. argument

    descriptor

    The constant's type, passed as the bootstrap method's 3. argument

    instructions

    The instruction builder the instructions are appended to

    classFile

    The class file the constant is in

    boxed

    If true, ensures the constant is of a reference type, boxing it if necessary

    returns

    The maximum stack height the generated instructions require and the (potentially new!) class file

    Definition Classes
    BootstrapArgumentLoading
  25. val logRewrites: Boolean
  26. val logUnknownDynamicConstants: Boolean
  27. val logUnresolvedDynamicConstants: Boolean
  28. val performRewriting: Boolean
  29. def registerDeferredAction(cp: (DynamicConstantRewriting.this)#Constant_Pool)(deferredAction: ((DynamicConstantRewriting.this)#ClassFile) => (DynamicConstantRewriting.this)#ClassFile): Unit
    Definition Classes
    Constant_PoolReader