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SPO600 Vectorization Lab

249 bytes added, 10:46, 12 February 2016
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# Compile this program on [[SPO600 Servers#AArch64|aarchie]] in such a way that the code is auto-vectorized.
# Annotate the emitted code (i.e., obtain a dissassembly via <code>objdump -d</code> and add comments to the instructions in <code>&lt;main&gt;</code> explaining what the code does).
# Review the vector instructions for AArch64. Find a way to scale an array of sound samples (see Lab 5) by a factor between 0.000-1.000 using SIMD. (Note: you may need to convert some data types).
# '''Write a blog post discussing your findings'''. Include:
#* The source code
#* Your annotated dissassembly listing
#* Your reflections on the experience and the results
#* Your proposed volume-sampling-via-SIMD solution.
=== Resources ===
* [https://gcc.gnu.org/projects/tree-ssa/vectorization.html Auto-Vectorization in GCC] - Main project page for the GCC auto-vectorizer.
* [http://locklessinc.com/articles/vectorize/ Auto-vectorization with gcc 4.7] - An excellent discussion of the capabilities and limitations of the GCC auto-vectorizer, intrinsics for providing hints to GCC, and other code pattern changes that can improve results. Note that there has been some improvement in the auto-vectorizer since this article was written. '''This article is strongly recommended.'''