Support for PowerPC

[barracuda156]

Could we have support for PowerPC as well? Currently only x86 and arm are there.

[mackron]

So c89atomic will by default use GCC's atomic intrinsics before falling back to any architecture-specific inlined assembly in the situation where those instrinsics are unavailable. If your compilation environment supports those intrinsics, I think it should "just work"? I'd be happy enough to add support for PowerPC inlined assembly for the fallback path, but that would need to be contributed by the community.

[barracuda156]

@ mackron As long as modern ones (__atomic*) are used, that will work with modern compilers, but those support C11/C++11. Old built-ins __sync* will only work for 32-bit values, but not for 64-bit. I think Xcode gcc-4.2 supports neither though (it is pre-C11).

[mackron]

I'd be happy to support PowerPC in some form if the community contributed it. I have no experience with PowerPC whatsoever nor any personal requirement for it so I have no motivation to do it personally.

Does PowerPC actually support 64-bit atomics? If it's not supported by the architecture it won't be support by c89atomic either (I have no interest in simulating it via a global mutex or anything).

[barracuda156]

Does PowerPC actually support 64-bit atomics? If it's not supported by the architecture it won't be support by c89atomic either (I have no interest in simulating it via a global mutex or anything).

ppc supports it only via libatomic (which works fine). ppc64 supports it in hardware.