Speculative load optimization

It seems that this optimization should not be performed when strict aliasing is disabled. However, GCC is being aggressive and performs speculative loads on struct fields even with-fno-strict-aliasing.

Should LLVM perform this load speculation even with strict aliasing disabled?

If no, what is the way to check for strict aliasing in the midend (with strict aliasing being a frontend concept)? Is it reasonable to check for presence of TBAA tags on the load instructions? And if there are any TBAA tags associated with loads, consider strict aliasing enabled.