[llvm] [CodeGen] Pass the atomic instruction to supportsUnalignedAtomics. NFC (PR #216621)

[Fabian Ritter via llvm-commits]

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@@ -2302,7 +2302,9 @@ class LLVM_ABI TargetLoweringBase {
   unsigned getMinCmpXchgSizeInBits() const { return MinCmpXchgSizeInBits; }
 
   /// Whether the target supports unaligned atomic operations.
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ritter-x2a wrote:

Whatever solution we end up with, please update the doc comment to refer to the new parameter, i.e., in the current version, say that the function returns whether this atomic instruction is supported if it is not naturally aligned.

https://github.com/llvm/llvm-project/pull/216621