Doesn't compile on ARM64

[cyb-r]

ARM64 doesn't have emmintrin.h which this module uses.

CMake Error at cmake/Anope.cmake:411 (message): /home/ansible/anope-2.0.12/modules/third/DiceServ-3.0.4/diceserv.cpp needs header file emmintrin.h but we were unable to locate that header file! Check that the header file is within the search path of your OS. Call Stack (most recent call first): modules/CMakeLists.txt:29 (calculate_depends) modules/third/DiceServ-3.0.4/CMakeLists.txt:1 (build_modules)

[CyberBotX]

Since DiceServ relies on x86 SIMD functions for the RNG, I suspect that it probably will not be able to be used on ARM64. From a quick search, I am unable to find any ARM64 analogues to the SIMD functions I utilized.

[CyberBotX]

So coming back to this after over 2 years, I actually found a workaround that involved using SIMD Everywhere from https://github.com/simd-everywhere/simde and this allowed DiceServ to compile on an ARM64 machine with no changes to the code otherwise. I basically just removed the #include <emmintrin.h> line and replaced it with:

#define SIMDE_ENABLE_NATIVE_ALIASES
#include <simde/x86/sse2.h>

This does rely on having the simde headers installed globally (which for me I was able to achieve on FreeBSD by installing the simde package, maybe Linux distros have something similiar). I only came across this myself when I was needing to install an IRCd as well as Anope on a Raspberry Pi 4B, so that is why I did not look into it much 2 years ago.

I think ideally at some point I'd rather just replace the PRNG with another one, but I haven't done enough research on which algorithms are both fast and reasonably random (there are some very, very bad algorithms out there).