[clang] [clang] Implement __builtin_{clzg,ctzg} (PR #83431)

[Eli Friedman via cfe-commits]

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@@ -662,6 +662,12 @@ def Clz : Builtin, BitShort_Int_Long_LongLongTemplate {
 
 // FIXME: Add int clzimax(uintmax_t)
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efriedma-quic wrote:

Probably; it's unlikely we're going to add them at this point.

https://github.com/llvm/llvm-project/pull/83431