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

[David Sherwood via llvm-commits]

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@@ -1480,57 +1480,21 @@ define i64 @same_exit_block_pre_inc_use1_reverse() {
 ; CHECK-NEXT:    [[P2:%.*]] = alloca [1024 x i8], align 1
 ; CHECK-NEXT:    call void @init_mem(ptr [[P1]], i64 1024)
 ; CHECK-NEXT:    call void @init_mem(ptr [[P2]], i64 1024)
-; CHECK-NEXT:    br i1 false, label [[SCALAR_PH:%.*]], label [[VECTOR_PH:%.*]]
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david-arm wrote:

This looks like a regression to me. Are you suggesting that we simply cannot ever check for dereferenceability in reverse loops for some fundamental reason or that the test itself was invalid? If it's the latter I'm happy to rewrite the test. :) It would be a shame to lose this functionality.

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