Box values of inline class types when passing to function as varargs

compiler/testData/codegen/box/inlineClasses/passInlineClassAsVararg.kt

@@ -0,0 +1,24 @@
+// !LANGUAGE: +InlineClasses
+
+inline class UInt(val value: Int)
+
+fun <T> takeVarargs(vararg e: T): T {
+    return e[e.size - 1]
+}
+
+fun test(u1: UInt, u2: UInt, u3: UInt?): Int {
+    val a = takeVarargs(u1, u2)
+    val b = takeVarargs(u3) ?: UInt(-1)
+    val c = takeVarargs(u1, u3) ?: UInt(-1)
+
+    return a.value + b.value + c.value
+}
+
+fun box(): String {
+    val u1 = UInt(0)
+    val u2 = UInt(1)
+    val u3 = UInt(2)
+    if (test(u1, u2, u3) != 1 + 2 + 2) return "fail"
+
+    return "OK"
+}

compiler/testData/codegen/bytecodeText/inlineClasses/boxInlineClassesOnPassingToVarargs.kt

@@ -0,0 +1,17 @@
+// !LANGUAGE: +InlineClasses
+
+inline class UInt(val u: Int)
+
+fun <T> takeVarargs(vararg e: T) {}
+
+fun test(u1: UInt, u2: UInt, u3: UInt?) {
+    takeVarargs(u1, u2) // 2 box
+    takeVarargs(u3)
+    takeVarargs(u1, u3) // box
+}
+
+// 3 INVOKESTATIC UInt\$Erased.box
+// 0 INVOKEVIRTUAL UInt.unbox
+
+// 0 valueOf
+// 0 intValue