[llvm] TargetLibraryInfo: Assume no libcalls in the default constructor (PR #92400)

[Teresa Johnson via llvm-commits]

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@@ -882,11 +885,19 @@ static void initialize(TargetLibraryInfoImpl &TLI, const Triple &T,
   TLI.addVectorizableFunctionsFromVecLib(ClVectorLibrary, T);
 }
 
-TargetLibraryInfoImpl::TargetLibraryInfoImpl() {
-  // Default to everything being available.
-  memset(AvailableArray, -1, sizeof(AvailableArray));
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teresajohnson wrote:

> No, that's the next step I'm working towards

Not sure I follow - what is the next step? afaict this PR does what @jhuber6 was describing (no longer default to everything being available). 

https://github.com/llvm/llvm-project/pull/92400