e156651190
Fixed the implementations of these builtin functions for targets that don't have native masked load instructions so that they do no loads if the vector mask is all off, and only do an (unaligned) vector load if both the first and last element of the mask are on. Otherwise they serialize and do scalar loads for only the active lanes. This fixes a number of potential sources of crashes due to accessing invalid memory.
============================== 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 and SSE4 instruction sets, though support for AVX should be available soon. For more information and examples, as well as a wiki and the bug database, see the ispc distribution site, http://ispc.github.com.