llvm-project

13799998 - [EquivalenceClasses] Use DenseMap instead of std::set. (NFC) (#134264)

[EquivalenceClasses] Use DenseMap instead of std::set. (NFC) (#134264) Replace the std::set with DenseMap, which removes the requirement for an ordering predicate. This also requires to allocate the ECValue objects separately. This patch uses a BumpPtrAllocator. Follow-up to https://github.com/llvm/llvm-project/pull/134075. Compile-time impact is mostly neutral or slightly positive: https://llvm-compile-time-tracker.com/compare.php?from=ee4e8197fa67dd1ed6e9470e00708e7feeaacd97&to=242e6a8e42889eebfc0bb5d433a4de7dd9e224a7&stat=instructions:u