[llvm] flang-rt: improve endian conversion performance (PR #218302)

[Slava Zakharin via llvm-commits]

================
@@ -31,6 +31,61 @@ RT_OFFLOAD_API_GROUP_BEGIN
 
 static inline RT_API_ATTRS void SwapEndianness(
     char *data, std::size_t bytes, std::size_t elementBytes) {
+  switch (elementBytes) {
----------------
vzakhari wrote:

Sorry, I do not see it.

https://github.com/llvm/llvm-project/pull/218302