[Mlir-commits] [flang] [mlir] [RFC][mlir] ViewLikeOpInterface method for detecting partial views. (PR #164020)

[Slava Zakharin]

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@@ -212,6 +212,10 @@ AliasResult AliasAnalysis::alias(Source lhsSrc, Source rhsSrc, mlir::Value lhs,
     if (lhsSrc.origin == rhsSrc.origin) {
       LLVM_DEBUG(llvm::dbgs()
                  << "  aliasing because same source kind and origin\n");
+      // TODO: we should return PartialAlias here. Need to decide
+      // if returning PartialAlias for fir.pack_array is okay;
+      // if not, then we need to handle it specially to still return
+      // MayAlias.
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vzakhari wrote:

I agree with you, Tom. I think the current algorithm in LocalAliasAnalysis (which I am not trying to affect too much, because this is not my goal) does not allow reasoning about partial aliases quite precisely.  So I feel okay returning `MayAlias` in cases where there might be an offset involved. At least, this makes the analysis conservatively correct.

https://github.com/llvm/llvm-project/pull/164020