[llvm] [LAA] Be more careful when evaluating AddRecs at symbolic max BTC. (PR #128061)

[David Sherwood via llvm-commits]

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@@ -72,10 +72,10 @@ define void @all_exits_dominate_latch_countable_exits_at_most_500_iterations_not
 ; CHECK-NEXT:          %gep.A = getelementptr inbounds i32, ptr %A, i64 %iv
 ; CHECK-NEXT:      Grouped accesses:
 ; CHECK-NEXT:        Group [[GRP3]]:
-; CHECK-NEXT:          (Low: %B High: (2000 + %B))
+; CHECK-NEXT:          (Low: %B High: inttoptr (i64 -1 to ptr))
 ; CHECK-NEXT:            Member: {%B,+,4}<nuw><%loop.header>
 ; CHECK-NEXT:        Group [[GRP4]]:
-; CHECK-NEXT:          (Low: %A High: (2000 + %A))
+; CHECK-NEXT:          (Low: %A High: inttoptr (i64 -1 to ptr))
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david-arm wrote:

I *think* I understand. It sounds like you're saying that without the early exit we don't really care if the runtime checks are nonsense or not because the entire loop is UB anyway? Whereas for early exit loops the loop may or may not be UB and so we do care about getting the right runtime checks.

https://github.com/llvm/llvm-project/pull/128061