llvm.coro.align returns the alignment of the coroutine frame in bytes.
llvm.coro.raw.frame.ptr.offset returns the byte offset of the raw memory block address (returned by the allocator) in the over-aligned coroutine frame. This is for switched-resume scheme only. The returned value is undefined if the coroutine frame is not over-aligned.
llvm.coro.raw.frame.ptr.addr returns the address storing the raw frame address. The returned address is either an alloca (before llvm.coro.begin) or a coroutine frame field (after llvm.coro.begin).