[llvm] [LV][NFC] Use APFloat class when printing out costs per lane (PR #201824)

[Florian Hahn via llvm-commits]

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@@ -47,6 +47,14 @@ using VectorParts = SmallVector<Value *, 2>;
 #define LV_NAME "loop-vectorize"
 #define DEBUG_TYPE LV_NAME
 
+#if !defined(NDEBUG)
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fhahn wrote:

I think this needs to match the guard for the ::print implementation, otherwise build may fail

```suggestion
#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
```

https://github.com/llvm/llvm-project/pull/201824