Add ir interpreter tests

compiler/testData/ir/interpreter/spreadOperator.kt

@@ -0,0 +1,36 @@
+@CompileTimeCalculation
+fun varargSum(quantityToSum: Int, vararg num: Int): Int {
+    var sum = 0
+    for (i in 0..(quantityToSum - 1)) {
+        if (i >= num.size) return sum
+        sum += num[i]
+    }
+    return sum
+}
+
+@CompileTimeCalculation
+fun sumWithVarargAtFirst(vararg num: Int, quantityToSum: Int = num.size) = varargSum(quantityToSum, *num)
+
+@CompileTimeCalculation
+fun concatenation(vararg str: String): String {
+    var result = ""
+    for (s in str) result += s
+    return result
+}
+
+@CompileTimeCalculation
+fun customArrayConcatenation(vararg array: Any?): String {
+    var result = ""
+    for (elem in array) result += elem.toString() + " "
+    return result
+}
+
+const val a1 = <!EVALUATED: `6`!>varargSum(3, 1, 2, 3)<!>
+const val a2 = <!EVALUATED: `3`!>varargSum(num = *intArrayOf(1, 2, 3), quantityToSum = 2)<!>
+const val a3 = <!EVALUATED: `21`!>varargSum(6, *intArrayOf(1, 2), 3, *intArrayOf(4, 5, 6))<!>
+
+const val b1 = <!EVALUATED: `6`!>sumWithVarargAtFirst(1, 2, 3)<!>
+const val b2 = <!EVALUATED: `6`!>sumWithVarargAtFirst(quantityToSum = 3, num = *intArrayOf(1, 2, 3))<!>
+
+const val c1 = <!EVALUATED: `1 2 3`!>concatenation(*arrayOf("1", " "), "2", *arrayOf(" ", "3"))<!>
+const val c2 = <!EVALUATED: `1 2.0 3 -1 -2.0 `!>customArrayConcatenation(*arrayOf(1, 2.0), "3", *arrayOf(-1, -2.0))<!>