public <T> void op(UnaryOp op, Local<T> target, Local<T> source) {
    addInstruction(
        new PlainInsn(op.rop(source.type), sourcePosition, target.spec(), source.spec()));
  }
Executes {@code op} and sets {@code target} to the result.
android/android_framework/dex-maker/src/main/java/com/android/dx/Code.java