[llvm] [WIP][X86] Add addlike PatFrags for AVX-512 disjoint OR folding (PR #166015)

[Matt Arsenault via llvm-commits]

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@@ -1180,6 +1180,24 @@ def or_disjoint : PatFrag<(ops node:$lhs, node:$rhs),
   }];
 }
 
+def addlike : PatFrags<(ops node:$lhs, node:$rhs),
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arsenm wrote:

This could be defined with PatFrags with the existing or_disjoint and add (for the isADDLike, we would need a new one for the xor case. But isADDLike seems somewhat vestigial before or disjoint worked. It probably shouldn't continue checking haveNoCommonBitsSet as it does now)

https://github.com/llvm/llvm-project/pull/166015