timothy from the surely-there's-a-perfectly-innocent-explanation dept.
MojoKid writes "Recently, industry analysts came forward with the dubious claim that Intel's Clover Trail+ low power processor for mobile devices had somehow seized a massive lead over ARM's products, though there were suspicious discrepancies in the popular AnTuTu benchmark that was utilized to showcase performance. It turns out that the situation is far shadier than initially thought. The version used in testing with the benchmark isn't just tilted to favor Intel — it seems to flat-out cheat to accomplish it. The new 3.3 version of AnTuTu was compiled using Intel's C++ Compiler, while GCC was used for the ARM variants. The Intel code was auto-vectorized, the ARM code wasn't — there are no NEON instructions in the ARM version of the application. Granted, GCC isn't currently very good at auto-vectorization, but NEON is now standard on every Cortex-A9 and Cortex-A15 SoC — and these are the parts people will be benchmarking. But compiler optimizations are just the beginning. Apparently the Intel code deliberately breaks the benchmark's function. At a certain point, it runs a loop that's meant to be performed 32x just once, then reports to the benchmark that the task completed successfully. Now, the optimization in question is part of ICC (the Intel C++ compiler), but was only added recently. It's not the kind of procedure you'd call by accident. AnTuTu has released an updated "new" version of the benchmark in which Intel performance drops back down 20-50%. Systems based on high-end ARM devices again win the benchmark overall, as they did previously."
The reason that every major university maintains a department of
mathematics is that it's cheaper than institutionalizing all those people.