[llvm] [LAA] Fix off-by-EltSize in negative-step deref bounds check (PR #211964)

[Florian Hahn via llvm-commits]

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@@ -90,10 +90,10 @@ define void @reverse_top_spills(ptr dereferenceable(16) %A, ptr dereferenceable(
 ; CHECK-NEXT:          %gep.A = getelementptr inbounds i8, ptr %A, i64 %iv
 ; CHECK-NEXT:      Grouped accesses:
 ; CHECK-NEXT:        Group GRP0:
-; CHECK-NEXT:          (Low: (5 + %B)<nuw> High: (17 + %B))
+; CHECK-NEXT:          (Low: (-4 + inttoptr (i64 -1 to ptr))<nsw> High: (17 + %B))
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fhahn wrote:

I think this is running into an independent bug, where we use the incorrect lower bound: https://github.com/llvm/llvm-project/pull/218388

https://github.com/llvm/llvm-project/pull/211964