[llvm] [MemProf] Avoid assertion checking loop under NDEBUG (NFC) (PR #138985)

[Teresa Johnson via llvm-commits]

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@@ -5050,6 +5050,45 @@ bool MemProfContextDisambiguation::initializeIndirectCallPromotionInfo(
   return true;
 }
 
+#ifndef NDEBUG
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teresajohnson wrote:

I could, but then I need to put that attribute back on the StackIdIndexIter def in this code that I had removed it from. My sense is that the `#ifdef` is simpler overall, wdyt?

https://github.com/llvm/llvm-project/pull/138985