Generate switch instruction for 'when' with unsigned subject

compiler/testData/codegen/box/unsignedTypes/whenByUnsigned.kt

@@ -0,0 +1,35 @@
+// WITH_RUNTIME
+// IGNORE_BACKEND: JS, JVM_IR
+
+const val M1: UInt = 2147483648u
+const val M2: ULong = 9223372036854775808UL
+
+fun testUInt(x: UInt) =
+    when (x) {
+        0u -> "none"
+        1u -> "one"
+        2u -> "two"
+        3u -> "three"
+        M1 -> "M1"
+        else -> "many"
+    }
+
+fun testULong(x: ULong) =
+    when (x) {
+        0UL -> "none"
+        1UL -> "one"
+        2UL -> "two"
+        3UL -> "three"
+        M2 -> "M2"
+        else -> "many"
+    }
+
+fun box(): String {
+    val t1 = listOf(0u, 1u, 2u, 3u, 4u, M1).map { testUInt(it) }
+    if (t1 != listOf("none", "one", "two", "three", "many", "M1")) throw AssertionError("UInt: $t1")
+
+    val t2 = listOf(0UL, 1UL, 2UL, 3UL, 4UL, M2).map { testULong(it) }
+    if (t2 != listOf("none", "one", "two", "three", "many", "M2")) throw AssertionError("ULong: $t2")
+
+    return "OK"
+}

compiler/testData/codegen/bytecodeText/unsignedTypes/whenByUnsigned.kt

@@ -0,0 +1,28 @@
+// WITH_RUNTIME
+// IGNORE_BACKEND: JVM_IR
+
+const val M1: UInt = 2147483648u
+
+fun testUInt1(x: UInt) =
+    when (x) {
+        0u -> "none"
+        1u -> "one"
+        2u -> "two"
+        3u -> "three"
+        else -> "many"
+    }
+
+fun testUInt2(x: UInt) =
+    when (x) {
+        0u -> "none"
+        1u -> "one"
+        2u -> "two"
+        3u -> "three"
+        M1 -> "M1"
+        else -> "many"
+    }
+
+// 2 SWITCH
+// ^ This captures both TABLESWITCH and LOOKUPSWITCH; we don't care about nuances of *SWITCH instruction generation here.
+
+// 0 IF_ICMP