PNaCl documentation: add SIMD vectors.

native_client_sdk/src/doc/faq.rst

 ##########################
 Frequently Asked Questions
 ##########################
 
 .. contents::
   :local:
   :backlinks: none
   :depth: 2
 
 This document answers some frequently asked questions about Native
@@ skipping 47 matching lines @@
 * **Portability:** Developers and users don't need to worry about
   already-released applications not working on new hardware: PNaCl
   already supports all architectures NaCl does, and as PNaCl evolves it
   gains support for new processors and fully uses their capabilities.
 
 .. TODO Expand on the PNaCl performance section in another document, and
 .. link to it here. How does one profile PNaCl code? What are common
 .. causes of slowness? How can code be made faster? What's the best way
 .. to use Pepper's asynchronous APIs? What do I need to know about
 .. threads and inter-thread communications? Can I use SIMD or other
-.. processor-specific instructions? What aboutt he GPU?
+.. processor-specific instructions? What about the GPU?
 
 For more details, refer to the :doc:`history behind and comparison of
 NaCl and PNaCl <nacl-and-pnacl>`.
 
 When should I use Native Client?
 --------------------------------
 
 The following are some typical use cases. For details, see the
 :doc:`Technical Overview <overview>`.
 
@@ skipping 27 matching lines @@
 | x86-64 | 25% |
 +--------+-----+
 |  ARM   | 10% |
 +--------+-----+
 
 Note that benchmark performance is sometimes bimodal, so different use
 cases are likely to achieve better or worse performance than the above
 averages. For example floating-point heavy code usually exhibits much
 lower overheads whereas very branch-heavy code often performs worse.
 
+Note that PNaCl supports performance features that are often used in
+native code such as :ref:`threading <language_support_threading>` and
+:ref:`Portable SIMD Vectors <portable_simd_vectors>`.
+
 For details, see:
 
 * `Adapting Software Fault Isolation to Contemporary CPU Architectures
   <https://nativeclient.googlecode.com/svn/data/site/NaCl_SFI.pdf>`_ (PDF).
 * `Native Client: A Sandbox for Portable, Untrusted x86 Code
   <http://research.google.com/pubs/pub34913.html>`_ (PDF).
 
 If your code isn't performing as close to native speed as you'd expect,
 :doc:`let us know <help>`!
 
@@ skipping 138 matching lines @@
 NPAPI is not supported by the Native Client SDK, and is `deprecated in
 Chrome
 <http://blog.chromium.org/2013/09/saying-goodbye-to-our-old-friend-npapi.html>`_.
 
 Does Native Client support SIMD vector instructions?
 ----------------------------------------------------
 
 Native Client currently supports SSE on x86 and NEON on ARM. Support for
 AVX on x86 is under way.
 
-Portable Native Client should support SIMD vectors in the near future.
+Portable Native Client supports portable SIMD vectors, as detailed in
+:ref:`Portable SIMD Vectors <portable_simd_vectors>`.
 
 Can I use Native Client for 3D graphics?
 ----------------------------------------
 
 Yes. Native Client supports `OpenGL ES 2.0
 <https://www.khronos.org/opengles/>`_.
 
 To alert the user regarding their hardware platform's 3D feature set
 before loading a large NaCl application, see :doc:`Vetting the driver in
 Javascript <devguide/coding/3D-graphics>`.
@@ skipping 277 matching lines @@
   you're loading the correct ``.nexe`` file by building a separate
   ``.nexe`` for each architecture, and using a ``.nmf`` manifest file to
   let the browser select the correct ``.nexe`` file. Note: the need to
   select a processor-specific ``.nexe`` goes away with Portable Native
   Client.
 * If things still aren't working, :doc:`ask for help <help>`!
 
 .. _CORS: http://en.wikipedia.org/wiki/Cross-origin_resource_sharing
 .. _naclports: https://code.google.com/p/naclports
 .. _Crouton: https://github.com/dnschneid/crouton