backend: enable and add tests for autoboxing

backend.native/tests/codegen/boxing/boxing10.kt

@@ -0,0 +1,9 @@
+fun main(args: Array<String>) {
+    val FALSE: Boolean? = false
+
+    if (FALSE != null) {
+        do {
+            println("Ok")
+        } while (FALSE)
+    }
+}

backend.native/tests/codegen/boxing/boxing11.kt

@@ -0,0 +1,12 @@
+fun printInt(x: Int) = println(x)
+
+class Foo(val value: Int?) {
+    fun foo() {
+        printInt(if (value != null) value else 42)
+    }
+}
+
+fun main(args: Array<String>) {
+    Foo(17).foo()
+    Foo(null).foo()
+}

backend.native/tests/codegen/boxing/boxing12.kt

@@ -0,0 +1,7 @@
+fun foo(x: Number) {
+    println(x.toByte())
+}
+
+fun main(args: Array<String>) {
+    foo(18)
+}

backend.native/tests/codegen/boxing/boxing2.kt

@@ -0,0 +1,17 @@
+fun printInt(x: Int) = println(x)
+fun printBoolean(x: Boolean) = println(x)
+
+fun foo(arg: Any) {
+    if (arg is Int)
+        printInt(arg)
+    else if (arg is Boolean)
+        printBoolean(arg)
+    else
+        println("other")
+}
+
+fun main(args: Array<String>) {
+    foo(1)
+    foo(true)
+    foo("Hello")
+}

backend.native/tests/codegen/boxing/boxing3.kt

@@ -0,0 +1,10 @@
+fun printInt(x: Int) = println(x)
+
+fun foo(arg: Int?) {
+    if (arg != null)
+        printInt(arg)
+}
+
+fun main(args: Array<String>) {
+    foo(42)
+}

backend.native/tests/codegen/boxing/boxing4.kt

@@ -0,0 +1,10 @@
+fun printInt(x: Int) = println(x)
+
+fun foo(arg: Any?) {
+    if (arg is Int? && arg != null)
+        printInt(arg)
+}
+
+fun main(args: Array<String>) {
+    foo(16)
+}

backend.native/tests/codegen/boxing/boxing5.kt

@@ -0,0 +1,10 @@
+fun printInt(x: Int) = println(x)
+
+fun foo(arg: Int?) {
+    printInt(arg ?: 16)
+}
+
+fun main(args: Array<String>) {
+    foo(null)
+    foo(42)
+}

backend.native/tests/codegen/boxing/boxing6.kt

@@ -0,0 +1,10 @@
+fun printInt(x: Int) = println(x)
+
+fun foo(arg: Any) {
+    printInt(arg as? Int ?: 16)
+}
+
+fun main(args: Array<String>) {
+    foo(42)
+    foo("Hello")
+}

backend.native/tests/codegen/boxing/boxing7.kt

@@ -0,0 +1,15 @@
+fun printInt(x: Int) = println(x)
+
+fun foo(arg: Any) {
+    val argAsInt = try {
+        arg as Int
+    } catch (e: ClassCastException) {
+        0
+    }
+    printInt(argAsInt)
+}
+
+fun main(args: Array<String>) {
+    foo(1)
+    foo("Hello")
+}

backend.native/tests/codegen/boxing/boxing8.kt

@@ -0,0 +1,9 @@
+fun foo(vararg args: Any?) {
+    for (arg in args) {
+        println(arg.toString())
+    }
+}
+
+fun main(args: Array<String>) {
+    foo(1, null, true, "Hello")
+}

backend.native/tests/codegen/boxing/boxing9.kt

@@ -0,0 +1,13 @@
+fun foo(vararg args: Any?) {
+    for (arg in args) {
+        println(arg.toString())
+    }
+}
+
+fun bar(vararg args: Any?) {
+    foo(1, *args, 2, *args, 3)
+}
+
+fun main(args: Array<String>) {
+    bar(null, true, "Hello")
+}