0933a77c1b
Specifically, launch all of the tasks in one statement, rather than still looping over spans in y and launching a collection of tasks across x for each span. This seems to give a few percent better performance.
============================== Intel(r) SPMD Program Compiler ============================== Welcome to the Intel(r) SPMD Program Compiler (ispc)! ispc is a new compiler for "single program, multiple data" (SPMD) programs. Under the SPMD model, the programmer writes a program that mostly appears to be a regular serial program, though the execution model is actually that a number of program instances execute in parallel on the hardware. ispc compiles a C-based SPMD programming language to run on the SIMD units of CPUs; it frequently provides a a 3x or more speedup on CPUs with 4-wide SSE units, without any of the difficulty of writing intrinsics code. ispc is an open source compiler under the BSD license; see the file LICENSE.txt. ispc supports Windows, Mac, and Linux, with both x86 and x86-64 targets. It currently supports the SSE2, SSE4, and AVX instruction sets. For more information and examples, as well as a wiki and the bug database, see the ispc distribution site, http://ispc.github.com.