[llvm] [SPIR-V] Don't lower builtin variadic functions (PR #188517)

[Nick Sarnie via llvm-commits]

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@@ -627,6 +633,9 @@ bool ExpandVariadics::expandCall(Module &M, IRBuilder<> &Builder, CallBase *CB,
   bool Changed = false;
   const DataLayout &DL = M.getDataLayout();
 
+  if (ABI->ignoreFunction(CB->getCalledFunction()))
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sarnex wrote:

The indirect path also calls `expandCall` where this check is, so I think we are okay.

https://github.com/llvm/llvm-project/pull/188517