[compiler-rt] [scudo] Update header without read-modify-write operation (PR #66955)

[via llvm-commits]

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@@ -128,19 +128,6 @@ inline void loadHeader(u32 Cookie, const void *Ptr,
     reportHeaderCorruption(const_cast<void *>(Ptr));
 }
 
-inline void compareExchangeHeader(u32 Cookie, void *Ptr,
-                                  UnpackedHeader *NewUnpackedHeader,
-                                  UnpackedHeader *OldUnpackedHeader) {
-  NewUnpackedHeader->Checksum =
-      computeHeaderChecksum(Cookie, Ptr, NewUnpackedHeader);
-  PackedHeader NewPackedHeader = bit_cast<PackedHeader>(*NewUnpackedHeader);
-  PackedHeader OldPackedHeader = bit_cast<PackedHeader>(*OldUnpackedHeader);
-  if (UNLIKELY(!atomic_compare_exchange_strong(
-          getAtomicHeader(Ptr), &OldPackedHeader, NewPackedHeader,
-          memory_order_relaxed)))
-    reportHeaderRace(Ptr);
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ChiaHungDuan wrote:

Done

https://github.com/llvm/llvm-project/pull/66955