[llvm] [BasicAA] Add Vscale GEP decomposition on variable index (PR #69152)

[Nikita Popov via llvm-commits]

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@@ -1165,6 +1204,46 @@ AliasResult BasicAAResult::aliasGEP(
   if (!V1Size.hasValue() || !V2Size.hasValue())
     return AliasResult::MayAlias;
 
+  // VScale Alias Analysis
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nikic wrote:

Please drop this code from the initial patch -- let's make sure everything works with vscale in the decomposition first, before we extend to also handling scalable location size.

https://github.com/llvm/llvm-project/pull/69152