[llvm] [DA] Check monotonicity for subscripts (PR #154527)

[Ryotaro Kasuga via llvm-commits]

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@@ -646,11 +646,11 @@ exit:
 define void @coeff_may_negative(ptr %a, i32 %k) {
 ; CHECK-LABEL: 'coeff_may_negative'
 ; CHECK-NEXT:  Src: store i8 42, ptr %idx.0, align 1 --> Dst: store i8 42, ptr %idx.0, align 1
-; CHECK-NEXT:    da analyze - none!
+; CHECK-NEXT:    da analyze - confused!
 ; CHECK-NEXT:  Src: store i8 42, ptr %idx.0, align 1 --> Dst: store i8 42, ptr %idx.1, align 1
-; CHECK-NEXT:    da analyze - output [*|<]!
+; CHECK-NEXT:    da analyze - confused!
 ; CHECK-NEXT:  Src: store i8 42, ptr %idx.1, align 1 --> Dst: store i8 42, ptr %idx.1, align 1
-; CHECK-NEXT:    da analyze - none!
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kasuga-fj wrote:

I believe this is a case where the test results were correctly updated. We cannot prove `%k` is non-zero from the IR.

https://github.com/llvm/llvm-project/pull/154527