[llvm] [DA] Ensure nsw flag is checked for StrongSIV addrecs (PR #178047)

[Ryotaro Kasuga via llvm-commits]

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@@ -293,10 +295,13 @@ cleanup:
 
 
 ; CHECK-LABEL: sub_aft_less
+; CHECK: %i = phi
+; CHECK-NOT: phi
 ; CHECK: %j = phi
-; CHECK: %j.1 = phi
-; CHECK: %j.2 = phi
-; CHECK: %j.3 = phi
+; CHECK-NOT: phi
+; CHECK: %sum = phi
+; CHECK-NOT: phi
+; CHECK: add.lcssa = phi
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kasuga-fj wrote:

For consistency, please refer to the other files in the same directory and rewrite in the same way.
(Although I don’t think either approach is particularly good.)

https://github.com/llvm/llvm-project/pull/178047