[llvm] RuntimeLibcalls: Add function signatures to RTLIB. (PR #226264)

[Matt Arsenault via llvm-commits]

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@@ -462,6 +503,37 @@ RuntimeLibcallsInfo::getFunctionTy(LLVMContext &Ctx, const Triple &TT,
     return {FunctionType::get(Type::getVoidTy(Ctx), ArgTys, false), Attrs};
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arsenm wrote:

Are these hand written cases obsoleted, or still useful given this system doesn't yet have a way to mark attributes?

https://github.com/llvm/llvm-project/pull/226264