[llvm] RuntimeLibcalls: Add bitset for available libcalls (PR #150869)

[Roger Ferrer Ibáñez via llvm-commits]

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@@ -597,23 +602,47 @@ void RuntimeLibcallEmitter::emitSystemRuntimeLibrarySetCalls(
         continue;
       }
 
+      size_t BitIdx = LibCallImpl->getEnumVal();
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rofirrim wrote:

Right, I see.

In our downstream we have additional runtime calls and we're computing a `BitsetIdx` that is exactly the size of `BitsetValues` so an assertion build fails. 

Maybe because of starting from 1 we should account that in the size of `BitsetValues`. Maybe

https://github.com/llvm/llvm-project/blob/e3620fe0685c656915977d55f822a82090041965/llvm/utils/TableGen/Basic/RuntimeLibcallsEmitter.cpp#L594-L595

should be `RuntimeLibcallImplDefList.size() + 1`?

https://github.com/llvm/llvm-project/pull/150869