Hacker News new | ask | show | jobs
by mhh__ 1657 days ago
I think we've been talking past eachother (I should have been more direct perhaps). This programming model is not what I had in mind - I completely accept your point about the Cray model but I meant something slightly dumber than loop parallelization.

In very tight situations it's common to write SIMD intrinsics directly rather than rely on the compilers ability to make the transformations itself. Intel's SIMD maybe be ugly but it is also very topologically easy to navigate, if that makes sense.

I'm going to write some arm SVE code and compare, at some point.

1 comments

Yeah the point with the Cray vector opcodes is that the SIMD instructions ARE the regular scalar/FPU instructions. The compiler doesn’t do anything to different when it vectorizes the loop. It is the CPU that does the vector optimization. The code just provides hints (to the CPU, not the compiler) about how to vectorize.