When by enum:

Generate TABLESWITCH/LOOKUPSWITCH bytecode command in case of "when" by enum entries

compiler/testData/codegen/boxWithStdlib/whenEnumOptimization/duplicatingItems.kt

@@ -0,0 +1,25 @@
+import kotlin.test.assertEquals
+
+enum class Season {
+    WINTER
+    SPRING
+    SUMMER
+    AUTUMN
+}
+
+fun bar(x : Season) : String {
+    when (x) {
+        Season.WINTER, Season.SPRING -> return "winter_spring"
+        Season.SUMMER, Season.SPRING -> return "summer"
+        else -> return "autumn"
+    }
+}
+
+fun box() : String {
+    assertEquals("winter_spring", bar(Season.WINTER))
+    assertEquals("winter_spring", bar(Season.SPRING))
+    assertEquals("summer", bar(Season.SUMMER))
+    assertEquals("autumn", bar(Season.AUTUMN))
+
+    return "OK"
+}