[clang] [clang] Add __builtin_start_object_lifetime builtin. (PR #82776)

[Haojian Wu via cfe-commits]

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@@ -896,6 +896,12 @@ def Launder : Builtin {
   let Prototype = "void*(void*)";
 }
 
+def StartObjectLifeTime : Builtin {
+  let Spellings = ["__builtin_start_object_lifetime"];
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hokein wrote:

I don't have strong opinion on the name. Since this builtin doesn't strictly align with std::start_lifetime_as, I think it's better to have some divergence in the name.

https://github.com/llvm/llvm-project/pull/82776