On Thu, Nov 5, 2015 at 9:12 AM, DNF <[email protected]> wrote:
> I have been looking through the performance tips section of the manual.
> Specifically, I am curious about @simd
> (http://docs.julialang.org/en/release-0.4/manual/performance-tips/#performance-annotations).
>
> When I cut and paste the code demonstrating the @simd macro, I don't get
> substantial speedups. Before updating from OSX Yosemite to El Capitan, I saw
> no speedup whatsoever. After the update, there is a small speedup (I ran the
> example repeatedly):
>
> julia> timeit(1000,1000)
> GFlop = 1.2292170133468385
> GFlop (SIMD) = 1.5351220575547964
>
>
> This contrasts sharply to the example in the documentation which shows a
> speedup from 1.95GFlop to 17.6GFlop.
>
> Does my computer not have simd? How can I tell?
>
> This is my versioninfo:
>
> Julia Version 0.4.0
> Commit 0ff703b* (2015-10-08 06:20 UTC)
> Platform Info:
> System: Darwin (x86_64-apple-darwin15.0.0)
> CPU: Intel(R) Core(TM) i7-4850HQ CPU @ 2.30GHz
> WORD_SIZE: 64
> BLAS: libopenblas (DYNAMIC_ARCH NO_AFFINITY Haswell)
> LAPACK: libopenblas
> LIBM: libopenlibm
> LLVM: libLLVM-3.3
>
You can check with `code_llvm(innersimd,
Tuple{Vector{Float32},Vector{Float32}})`
