Package ghidra.pcode.emu.jit.alloc

Enum Class NoHandler

java.lang.Object
java.lang.Enum<NoHandler>
ghidra.pcode.emu.jit.alloc.NoHandler
All Implemented Interfaces:
VarHandler, Serializable, Comparable<NoHandler>, Constable
public enum NoHandler extends Enum<NoHandler> implements VarHandler
A dummy handler for values/variables that are not allocated in JVM locals

Every operation on this handler will throw an exception at code generation time.

  • Enum Constant Details

    • INSTANCE

      public static final NoHandler INSTANCE
      Singleton

  • Method Details

    • values

      public static NoHandler[] values()
      Returns an array containing the constants of this enum class, in the order they are declared.
      Returns:
      an array containing the constants of this enum class, in the order they are declared

    • valueOf

      public static NoHandler valueOf(String name)
      Returns the enum constant of this class with the specified name. The string must match exactly an identifier used to declare an enum constant in this class. (Extraneous whitespace characters are not permitted.)
      Parameters:
      name - the name of the enum constant to be returned.
      Returns:
      the enum constant with the specified name
      Throws:
      IllegalArgumentException - if this enum class has no constant with the specified name
      NullPointerException - if the argument is null

    • vn

      public Varnode vn()
      Description copied from interface: VarHandler
      Get the complete varnode accessible to this handler
      Specified by:
      vn in interface VarHandler
      Returns:
      the varnode

    • type

      public JitType type()
      Description copied from interface: VarHandler
      Get the p-code type of the local variable this handler uses.
      Specified by:
      type in interface VarHandler
      Returns:
      the type

    • genLoadToStack

      public <TT extends Types.BPrim<?>, TJT extends JitType.SimpleJitType<TT, TJT>, N extends Emitter.Next> Emitter<Emitter.Ent<N,TT>> genLoadToStack(Emitter<N> em, JitCodeGenerator<?> gen, TJT type, Opnd.Ext ext)
      Description copied from interface: VarHandler
      Emit bytecode to load the varnode's value onto the JVM stack.
      Specified by:
      genLoadToStack in interface VarHandler
      Type Parameters:
      TT - the JVM type of the value to load onto the stack
      TJT - the p-code type of the value to load onto the stack
      N - the incoming stack
      Parameters:
      em - the emitter typed with the incoming stack
      gen - the code generator
      type - the p-code type of the value expected on the JVM stack by the proceeding bytecode
      ext - the kind of extension to apply when adjusting from JVM size to varnode size
      Returns:
      the emitter typed with the resulting stack

    • genLoadToOpnd

      public <N extends Emitter.Next> Opnd.OpndEm<JitType.MpIntJitType,N> genLoadToOpnd(Emitter<N> em, JitCodeGenerator<?> gen, JitType.MpIntJitType type, Opnd.Ext ext, Scope scope)
      Description copied from interface: VarHandler
      Emit bytecode to load the varnode's value into several locals.
      Specified by:
      genLoadToOpnd in interface VarHandler
      Type Parameters:
      N - the incoming stack
      Parameters:
      em - the emitter typed with the incoming stack
      gen - the code generator
      type - the p-code type of the value expected on the JVM stack by the proceeding bytecode
      ext - the kind of extension to apply
      scope - a scope for generating temporary local storage
      Returns:
      the operand containing the locals, and the emitter typed with the incoming stack

    • genLoadLegToStack

      public <N extends Emitter.Next> Emitter<Emitter.Ent<N,Types.TInt>> genLoadLegToStack(Emitter<N> em, JitCodeGenerator<?> gen, JitType.MpIntJitType type, int leg, Opnd.Ext ext)
      Description copied from interface: VarHandler
      Emit bytecode to load one leg of a multi-precision value from the varnode onto the JVM stack.
      Specified by:
      genLoadLegToStack in interface VarHandler
      Type Parameters:
      N - the incoming stack
      Parameters:
      em - the emitter typed with the incoming stack
      gen - the code generator
      type - the p-code type of the complete multi-precision value
      leg - the index of the leg to load, 0 being least significant
      ext - the kind of extension to apply
      Returns:
      the emitter typed with the resulting stack, i.e., having the int leg pushed onto it

    • genLoadToArray

      public <N extends Emitter.Next> Emitter<Emitter.Ent<N,Types.TRef<int[]>>> genLoadToArray(Emitter<N> em, JitCodeGenerator<?> gen, JitType.MpIntJitType type, Opnd.Ext ext, Scope scope, int slack)
      Description copied from interface: VarHandler
      Emit bytecode to load the varnode's value into an integer array in little-endian order, pushing its ref onto the JVM stack.
      Specified by:
      genLoadToArray in interface VarHandler
      Type Parameters:
      N - the incoming stack
      Parameters:
      em - the emitter typed with the incoming stack
      gen - the code generator
      type - the p-code type of the complete multi-precision value
      ext - the kind of extension to apply
      scope - a scope for generating temporary local storage
      slack - the number of additional, more significant, elements to allocate in the array
      Returns:
      the emitter typed with the resulting stack, i.e., having the ref pushed onto it

    • genLoadToBool

      public <N extends Emitter.Next> Emitter<Emitter.Ent<N,Types.TInt>> genLoadToBool(Emitter<N> em, JitCodeGenerator<?> gen)
      Description copied from interface: VarHandler
      Emit bytecode to load the varnode's value, interpreted as a boolean, as an integer onto the JVM stack.
      Specified by:
      genLoadToBool in interface VarHandler
      Type Parameters:
      N - the incoming stack
      Parameters:
      em - the emitter typed with the incoming stack
      gen - the code generator
      Returns:
      the emitter typed with the resulting stack, i.e., having the int boolean pushed onto it

    • genStoreFromStack

      public <FT extends Types.BPrim<?>, FJT extends JitType.SimpleJitType<FT, FJT>, N1 extends Emitter.Next, N0 extends Emitter.Ent<N1, FT>> Emitter<N1> genStoreFromStack(Emitter<N0> em, JitCodeGenerator<?> gen, FJT type, Opnd.Ext ext, Scope scope)
      Description copied from interface: VarHandler
      Emit bytecode to store a value into a variable from the JVM stack.
      Specified by:
      genStoreFromStack in interface VarHandler
      Type Parameters:
      FT - the JVM type of the value on the stack
      FJT - the p-code type of the value on the stack
      N1 - the tail of the incoming stack
      N0 - the incoming stack having the value to store on top
      Parameters:
      em - the emitter typed with the incoming stack
      gen - the code generator
      type - the p-code type of the value on the stack
      ext - the kind of extension to apply
      scope - a scope for generating temporary local storage
      Returns:
      the emitter typed with the resulting stack, i.e., having popped the value

    • genStoreFromOpnd

      public <N extends Emitter.Next> Emitter<N> genStoreFromOpnd(Emitter<N> em, JitCodeGenerator<?> gen, Opnd<JitType.MpIntJitType> opnd, Opnd.Ext ext, Scope scope)
      Description copied from interface: VarHandler
      Emit bytecode to store a varnode's value from several locals.
      Specified by:
      genStoreFromOpnd in interface VarHandler
      Type Parameters:
      N - the incoming stack
      Parameters:
      em - the emitter typed with the incoming stack
      gen - the code generator
      opnd - the operand whose locals contain the value to be stored
      ext - the kind of extension to apply
      scope - a scope for generating temporary local storage
      Returns:
      the emitter typed with the incoming stack

    • genStoreFromArray

      public <N1 extends Emitter.Next, N0 extends Emitter.Ent<N1, Types.TRef<int[]>>> Emitter<N1> genStoreFromArray(Emitter<N0> em, JitCodeGenerator<?> gen, JitType.MpIntJitType type, Opnd.Ext ext, Scope scope)
      Description copied from interface: VarHandler
      Emit bytecode to store a varnode's value from an array of integer legs, in little endian order
      Specified by:
      genStoreFromArray in interface VarHandler
      Type Parameters:
      N1 - the tail of the incoming stack
      N0 - the incoming stack having the array ref on top
      Parameters:
      em - the emitter typed with the incoming stack
      gen - the code generator
      type - the p-code type of the value on the stack
      ext - the kind of extension to apply
      scope - a scope for generating temporary local storage
      Returns:
      the emitter typed with the resulting stack, i.e., having popped the array

    • subpiece

      public VarHandler subpiece(Endian endian, int byteOffset, int maxByteSize)
      Description copied from interface: VarHandler
      Create a handler for a PcodeOp.SUBPIECE of a value.

      To implement subpiece, we could load the entire varnode and then extract the designated portion. Or, we could load only the designated portion, averting any code and execution cost of loading the un-designated portions. We accomplish this by re-writing the subpiece op and a load of the sub-varnode.

      Specified by:
      subpiece in interface VarHandler
      Parameters:
      endian - the endianness of the emulation target
      byteOffset - the number of least-significant bytes to remove
      maxByteSize - the maximum size of the resulting variable. In general, a subpiece should never exceed the size of the parent varnode, but if it does, this will truncate that excess.
      Returns:
      the resulting subpiece handler