[clang] [CIR] Upstream minimal builtin function call support (PR #142981)

[Erich Keane via cfe-commits]

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@@ -44,16 +44,25 @@ class CIRGenCalleeInfo {
 class CIRGenCallee {
   enum class SpecialKind : uintptr_t {
     Invalid,
+    Builtin,
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erichkeane wrote:

Line 49 needs to be updated for this.

https://github.com/llvm/llvm-project/pull/142981