Add ir interpreter tests

compiler/testData/ir/interpreter/helpers/utils/kotlinUtils.kt

@@ -0,0 +1,29 @@
+package kotlin
+
+public inline val Char.code: Int get() = this.toInt()
+
+expect fun Double.isNaN(): Boolean
+expect fun Float.isNaN(): Boolean
+
+public data class Pair<out A, out B>(public val first: A, public val second: B) : Serializable {
+    public override fun toString(): String = "($first, $second)"
+}
+
+public infix fun <A, B> A.to(that: B): Pair<A, B> = Pair(this, that)
+
+public fun <T> Pair<T, T>.toList(): List<T> = listOf(first, second)
+
+public data class Triple<out A, out B, out C>(
+    public val first: A, public val second: B, public val third: C
+) : Serializable {
+    public override fun toString(): String = "($first, $second, $third)"
+}
+
+public fun <T> Triple<T, T, T>.toList(): List<T> = listOf(first, second, third)
+
+public fun checkIndexOverflow(index: Int): Int {
+    if (index < 0) {
+        throw kotlin.ArithmeticException("Index overflow has happened.")
+    }
+    return index
+}