A small number of defines are exposed and can be used to finetune the behavior.
This define prevents the usage of intrinsics unless explicitly requested by the integration manually (e.g. you can still defined RTM_SSE2_INTRINSICS yourself). Everything will default to pure scalar implementations.
This enables the usage of the POPCNT intrinsics when available on x86/x64 CPUs. It is currently not possible to determine at compile time when it is supported. For example Haswell CPUs have support for AVX2 but not POPCNT. The macro is automatically enabled on Xbox One but not yet on PlayStation 4 (even though it is supported, contributions welcome).