[clang] [llvm] [mlir] [Offload] Rework offloading entry type to be more generic (PR #124018)

[Shilei Tian via llvm-commits]

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@@ -24,11 +24,24 @@ namespace offloading {
 /// This is the record of an object that just be registered with the offloading
 /// runtime.
 struct EntryTy {
+  /// Reserved bytes used to detect an older version of the struct, always zero.
+  uint64_t Reserved = 0x0;
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shiltian wrote:

I assume this is used to check, if the leading 64-bit is zero, it is the old struct?

https://github.com/llvm/llvm-project/pull/124018