[llvm] [LAA] Add stencil group merging to reduce runtime pointer checks (PR #187252)

[David Sherwood via llvm-commits]

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@@ -3545,3 +3545,283 @@ outer.latch:
 exit:
   ret void
 }
+
+;; Test 28: A member whose constant offset is too far from the base.
+;; 7 loads from %a at offsets {C - s1 - s2 - s3, +-s1, +-s2, +-s3}.
+;; @constant_offset_too_large: C = -2^63. abs(C) is 2^63, more than int64
+;; max, so getStencilStrideUpperLimit finds no stride limit and the DepSet is
+;; skipped. Checks: 7 before, 7 after.
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david-arm wrote:

When skipping stencil merging I don't think comments like `Checks: 7 before, 7 after.` add any value, since they will be obviously the same.

https://github.com/llvm/llvm-project/pull/187252