[llvm] RuntimeLibcalls: Add bitset for available libcalls (PR #150869)

[Nikita Popov via llvm-commits]

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@@ -53,8 +53,64 @@ static inline auto libcall_impls() {
   return enum_seq(static_cast<RTLIB::LibcallImpl>(1), RTLIB::NumLibcallImpls);
 }
 
+/// Manage a bitset representing the list of available libcalls for a module.
+///
+/// Most of this exists because std::bitset cannot be statically constructed in
+/// a size large enough before c++23
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nikic wrote:

Isn't this what llvm/include/llvm/ADT/Bitset.h is for?

https://github.com/llvm/llvm-project/pull/150869