arithmetic test

backend.native/tests/codegen/function/arithmetic.kt

@@ -0,0 +1,5 @@
+fun square(a:Int):Int = a * a
+fun sumOfSquares(a:Int, b:Int):Int = square(a) + square(b)
+fun diffOfSquares(a:Int, b:Int):Int = square(a) - square(b)
+fun mod(a:Int,b:Int):Int = a / b
+fun remainder(a:Int, b:Int):Int = a % b