Java inline assembly transferring variables

Question

Hello I'm trying to do simple java code with inline assembly. In asm procedure I want to do some operations on java variables here are my codes

public class Add {
    public static void main(String[] args) {
          int a=5;
          int b=4;
          int c=0;

            System.loadLibrary("native");
            (new Add()).nativeCode();


    }

    public native void nativeCode();
}

And Asm procedure

global _Java_Add_nativeCode
section .text
_Java_Add_nativeCode:
mov eax, a
mov ebx, b
add eax,ebx 
mov c,eax 

I'm trying to do operations on variables like in C++ but Nasm gives me an error symbol 'a' undefinied etc. Is there any way to do operation on variables declared in java in ASM procedure?

Answer 1

a is a virtual variable. The only way to do this at the moment is to implement a method call in C via JNI. I suggest you use javah to generate C code and use asm from that. Note: this will be many time slower than doing the same thing in Java (and many time more complicated)

In Java 9 you might be able to use user defined intrinsics. This will allow you to add assembly into Java to use instructions Java doesn't currently use like XMM.