[llvm] [AArch64MIPeepholeOpt] Coalesce sibling base-address materializations (PR #223682)

[via llvm-commits]

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whokeke wrote:

Done — "item 8" was referring to a position in an internal numbered list of planned peepholes that doesn't mean anything to readers of this file. Replaced with a direct reference to AArch64MIPeepholeOptImpl::shareBaseAddresses.

https://github.com/llvm/llvm-project/pull/223682