[llvm] DenseMap: support enum class keys (PR #95972)

[Ramkumar Ramachandra via llvm-commits]

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@@ -267,6 +267,30 @@ TEST(MapVectorTest, NonCopyable) {
   ASSERT_EQ(*MV.find(2)->second, 2);
 }
 
+TEST(MapVectorTest, EnumClassKey) {
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artagnon wrote:

There's no DenseMapTest.cpp. Perhaps just use DenseMap directly in MapVectorTest.cpp?

https://github.com/llvm/llvm-project/pull/95972