[llvm] [InstCombine] Canonicalize more saturated-add variants (PR #100008)

[Craig Topper via llvm-commits]

topperc wrote:

> @topperc Is this PR ready to merge?

Please do not ping a patch more than once per week per the coding standards. https://llvm.org/docs/CodeReview.html#lgtm-how-a-patch-is-accepted

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Note that, if a reviewer has requested a particular community member to review, and after a week that community member has yet to respond, feel free to ping the patch (which literally means submitting a comment on the patch with the word, “Ping.”), or alternatively, ask the original reviewer for further suggestions.
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https://github.com/llvm/llvm-project/pull/100008