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

[Ryotaro Kasuga via llvm-commits]

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@@ -465,13 +465,13 @@ for.end12:                                        ; preds = %for.end12.loopexit,
 define void @gcd7(i32 %n, ptr %A, ptr %B) nounwind uwtable ssp {
 ; CHECK-LABEL: 'gcd7'
 ; CHECK-NEXT:  Src: store i32 %7, ptr %arrayidx6, align 4 --> Dst: store i32 %7, ptr %arrayidx6, align 4
-; CHECK-NEXT:    da analyze - output [* *]!
+; CHECK-NEXT:    da analyze - confused!
 ; CHECK-NEXT:  Src: store i32 %7, ptr %arrayidx6, align 4 --> Dst: %11 = load i32, ptr %arrayidx12, align 4
-; CHECK-NEXT:    da analyze - flow [* *|<]!
+; CHECK-NEXT:    da analyze - confused!
 ; CHECK-NEXT:  Src: store i32 %7, ptr %arrayidx6, align 4 --> Dst: store i32 %11, ptr %B.addr.12, align 4
 ; CHECK-NEXT:    da analyze - confused!
 ; CHECK-NEXT:  Src: %11 = load i32, ptr %arrayidx12, align 4 --> Dst: %11 = load i32, ptr %arrayidx12, align 4
-; CHECK-NEXT:    da analyze - input [* *]!
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kasuga-fj wrote:

"I'm not entirely sure whether these changes are reasonable. Several `sext` instructions have been inserted, which seems to complicate things.

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