[llvm] [IR] Remove the AtomicMem*Inst helper classes (PR #138710)

[Nikita Popov via llvm-commits]

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@@ -61,11 +61,11 @@ void expandMemSetAsLoop(MemSetInst *MemSet);
 /// Expand \p MemSetPattern as a loop. \p MemSet is not deleted.
 void expandMemSetPatternAsLoop(MemSetPatternInst *MemSet);
 
-/// Expand \p AtomicMemCpy as a loop. \p AtomicMemCpy is not deleted.
-void expandAtomicMemCpyAsLoop(AtomicMemCpyInst *AtomicMemCpy,
+/// Expand an atomic \p MemCpy as a loop. \p AtomicMemCpy is not deleted.
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nikic wrote:

`\p` refers to parameter names, so this doc comment shouldn't change.

https://github.com/llvm/llvm-project/pull/138710