[clang] [ClangFE] Improve handling of casting of atomic memory operations. (PR #86691)

[Matt Arsenault via cfe-commits]

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@@ -1399,13 +1401,22 @@ RValue AtomicInfo::convertAtomicTempToRValue(Address addr,
       LVal.getBaseInfo(), TBAAAccessInfo()));
 }
 
+static bool shouldCastToInt(llvm::Type *ValTy, bool CmpXchg) {
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arsenm wrote:

I don't understand the CmpXchg parameter. Also needs a docstring 

https://github.com/llvm/llvm-project/pull/86691