Package ghidra.pcode.emu.jit.gen.op

Enum Class IntSubOpGen

java.lang.Object
java.lang.Enum<IntSubOpGen>
ghidra.pcode.emu.jit.gen.op.IntSubOpGen
All Implemented Interfaces:
BinOpGen<JitIntSubOp>, IntOpBinOpGen<JitIntSubOp>, OpGen<JitIntSubOp>, Serializable, Comparable<IntSubOpGen>, Constable
public enum IntSubOpGen extends Enum<IntSubOpGen> implements IntOpBinOpGen<JitIntSubOp>
The generator for a int_sub.

This uses the binary operator generator and simply emits isub or lsub depending on the type.

This uses the same multi-precision integer strategy and pattern as IntAddOpGen.

  • Enum Constant Details

    • GEN

      public static final IntSubOpGen GEN
      The generator singleton

  • Method Details

    • values

      public static IntSubOpGen[] 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 IntSubOpGen 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

    • isSigned

      public boolean isSigned()
      Description copied from interface: BinOpGen
      Whether this operator is signed

      In many cases, the operator itself is not affected by the signedness of the operands; however, if size adjustments to the operands are needed, this can determine how those operands are extended.

      Specified by:
      isSigned in interface BinOpGen<JitIntSubOp>
      Returns:
      true for signed, false if not

    • opForInt

      public <N2 extends Emitter.Next, N1 extends Emitter.Ent<N2, Types.TInt>, N0 extends Emitter.Ent<N1, Types.TInt>> Emitter<Emitter.Ent<N2,Types.TInt>> opForInt(Emitter<N0> em, JitType.IntJitType type)
      Description copied from interface: IntOpBinOpGen
      Emit the JVM bytecode to perform the operator with intF operands on the stack.
      Specified by:
      opForInt in interface IntOpBinOpGen<JitIntSubOp>
      Type Parameters:
      N2 - the tail of the incoming stack
      N1 - the tail of the incoming stack including the right operand
      N0 - the incoming stack with the right and left operands on top
      Parameters:
      em - the emitter typed with the incoming stack
      type - the p-code type of the operands
      Returns:
      the emitter typed with the resulting stack, i.e., the tail with the result pushed

    • opForLong

      public <N2 extends Emitter.Next, N1 extends Emitter.Ent<N2, Types.TLong>, N0 extends Emitter.Ent<N1, Types.TLong>> Emitter<Emitter.Ent<N2,Types.TLong>> opForLong(Emitter<N0> em, JitType.LongJitType type)
      Description copied from interface: IntOpBinOpGen
      Emit the JVM bytecode to perform the operator with long operands on the stack.
      Specified by:
      opForLong in interface IntOpBinOpGen<JitIntSubOp>
      Type Parameters:
      N2 - the tail of the incoming stack
      N1 - the tail of the incoming stack including the right operand
      N0 - the incoming stack with the right and left operands on top
      Parameters:
      em - the emitter typed with the incoming stack
      type - the p-code type of the operands
      Returns:
      the emitter typed with the resulting stack, i.e., the tail with the result pushed

    • genRunMpInt

      public <THIS extends JitCompiledPassage> Emitter<Emitter.Bot> genRunMpInt(Emitter<Emitter.Bot> em, Local<Types.TRef<THIS>> localThis, JitCodeGenerator<THIS> gen, JitIntSubOp op, JitType.MpIntJitType type, Scope scope)
      Emit the JVM bytecode to perform the operator with multi-precision operands.

      The strategy here follows from grade-school long subtraction. We assert that there are at least two legs, otherwise we would have just emitted a single sub bytecode. This allows us to unconditionally initialize the subtraction with genMpIntLegSubGivesBorrow(Emitter, SimpleOpnd, SimpleOpnd, boolean, Scope) and terminate it with genMpIntLegSubTakesBorrow(Emitter, SimpleOpnd, SimpleOpnd, Scope). When there are more than 2 legs, we use genMpIntLegSubTakesAndGivesBorrow(Emitter, SimpleOpnd, SimpleOpnd, boolean, Scope) as many times as necessary in the middle. For all legs, we store the result and append it as a leg to the final output.

      Specified by:
      genRunMpInt in interface IntOpBinOpGen<JitIntSubOp>
      Type Parameters:
      THIS - the type of the generated passage
      Parameters:
      em - the emitter typed with the empty stack
      localThis - a handle to the local holding the this reference
      gen - the code generator
      op - the p-code op
      type - the p-code type of the operands
      scope - a scope for generating temporary local storage
      Returns:
      the emitter typed with the empty stack