> I believe all x64 CPUs support SSE2. I'm not sure if its mandatory in the > spec, or just that all manufacturers included it. > The Apple chips, like most tablet/phone chips, are ARM instruction set > (which is neither x86 or x64) - so they don't support SSE at all; but > there > are equivalents of SIMD operations for ARM. > For best portability, the nosse will work everywhere; but for any cpu > which > has sse, the sse version is much faster.
I tried using crypto_scrypt-sse.c on iOS. The code doesn't even compile. It stops at "#error "SSE2 instruction set not enabled"" within emmintrin.h So it's good to know that it fails to compile, as opposed to crashing at runtime. crypto_scrypt-sse.c works fine on OS X though. Since I'm not an expert on how CPUs progress over time, I thought I'd ask, how likely is it that CPUs in Macs would all of a sudden stop supporting SSE? I'm pretty sure this is very unlikely (without Apple at least providing some emulator like they did when migrating from PowerPC to Intel years ago), but I want to be sure.
