ceph/src/boost/libs/endian/doc/mini_review_topics.html

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  18     <b>
  19     <font size="6">Endian </font></b><font size="6"><b>Mini-Review</b></font></td>
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  26     <td><b>
  27     <a href="index.html">Endian Home</a>&nbsp;&nbsp;&nbsp;&nbsp;
  28     <a href="conversion.html">Conversion Functions</a>&nbsp;&nbsp;&nbsp;&nbsp;
  29     <a href="arithmetic.html">Arithmetic Types</a>&nbsp;&nbsp;&nbsp;&nbsp;
  30     <a href="buffers.html">Buffer Types</a>&nbsp;&nbsp;&nbsp;&nbsp;
  31     <a href="choosing_approach.html">Choosing Approach</a></b></td>
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  34 <p></p>
  35
  36 <p>The results of the Boost.Endian formal review included a list of issues to be
  37 resolved before a mini-review.</p>
  38
  39 <p>The issues are shown in <b>bold</b> below, with the resolution indicated.</p>
  40
  41   <p><b>1. Common use case scenarios should be developed.</b></p>
  42   <blockquote>
  43
  44   <p>Done. The documentation have been refactored. A page is now devoted to
  45   <a href="choosing_approach.html">Choosing the Approach</a> to endianness. See
  46   <a href="choosing_approach.html#Use-cases">Use cases</a> for use case
  47   scenarios.</p>
  48   </blockquote>
  49   <p><b>2. Example programs should be developed for the common use case scenarios.</b></p>
  50   <blockquote>
  51   <p>Done. See <a href="choosing_approach.html">Choosing the Approach</a>.
  52   Example code has been added throughout.</p>
  53   </blockquote>
  54   <p><b>3. Documentation should illuminate the differences between endian
  55 integer/float type and endian conversion approaches to the common use
  56 case scenarios, and provide guidelines for choosing the most appropriate
  57 approach in user's applications.</b></p>
  58   <blockquote>
  59   <p>Done. See <a href="choosing_approach.html">Choosing the Approach</a>.</p>
  60   </blockquote>
  61   <p><b>4 .Conversion functions supplying results via return should be provided.</b></p>
  62   <blockquote>
  63   <p>Done. See <a href="conversion.html">ConversionFunctions</a>.</p>
  64   </blockquote>
  65   <p><b>5. Platform specific performance enhancements such as use of compiler intrinsics or relaxed alignment requirements should be supported.</b></p>
  66   <blockquote>
  67   <p>Done. Compiler (Clang, GCC, VisualC++, etc.) intrinsics and built-in
  68   functions are used in the implementation where appropriate, as requested. See
  69   <a href="index.html#Intrinsic">Built-in support for Intrinsics</a>. See
  70   <a href="index.html#Timings">Timings for Example 2</a> to gauge the impact of
  71   intrinsics.</p>
  72   </blockquote>
  73   <p><b>6. Endian integer (and floating) types should be implemented via the
  74 conversion functions. If that can't be done efficiently, consideration
  75 should be given to expanding the conversion function signatures to
  76 resolve the inefficiencies.</b></p>
  77   <blockquote>
  78   <p>Done. For the endian types, the implementation uses the endian conversion
  79   functions, and thus the intrinsics, as requested.</p>
  80   </blockquote>
  81   <p><b>7. Benchmarks that measure performance should be provided. It should be
  82 possible to compare platform specific performance enhancements against
  83 portable base implementations, and to compare endian integer approaches
  84 against endian conversion approaches for the common use case scenarios.</b></p>
  85   <blockquote>
  86   <p>Done. See <a href="index.html#Timings">Timings for Example 2</a>. The <code>endian/test</code> directory
  87   also contains several additional benchmark and speed test programs.</p>
  88   </blockquote>
  89   <p><b>8. Float (32-bits) and double (64-bits) should be supported. IEEE 754 is
  90 the primary use case.</b></p>
  91   <blockquote>
  92   <p>Done. The <a href="buffers.html">endian buffer types</a>,&nbsp;
  93   <a href="arithmetic.html">endian arithmetic types</a> and
  94   <a href="conversion.html">endian conversion functions</a> now support 32-bit (<code>float)</code>
  95   and 64-bit <code>(double)</code> floating point, as requested.</p>
  96   </blockquote>
  97   <p><b>9. Support for user defined types (UDTs) is desirable, and should be
  98 provided where there would be no conflict with the other concerns.</b></p>
  99   <blockquote>
 100   <p>Done. See <a href="conversion.html#Customization-points">Customization
 101   points for user-defined types (UDTs)</a>.</p>
 102   </blockquote>
 103   <p><b>10. There is some concern that endian integer/float arithmetic operations
 104 might used inadvertently or inappropriately. The impact of adding an endian_buffer
 105   class without arithmetic operations should be investigated.</b></p>
 106   <blockquote>
 107   <p>Done. The endian types have been decomposed into class template <code>
 108   <a href="buffers.html">endian_buffer</a></code> and class template <code>
 109   <a href="arithmetic.html">endian_arithmetic</a></code>. Class
 110   <code>endian_buffer</code> is a public base class for <code>endian_arithmetic</code>,
 111   and can also be used by users as a stand-alone class.</p>
 112   </blockquote>
 113   <p><b>11. Stream insertion and extraction of the endian integer/float types should
 114   be documented and included in the test coverage.</b></p>
 115   <blockquote>
 116   <p>Done. See <a href="buffers.html#Stream-inserter">Stream inserter</a> and
 117   <a href="buffers.html#Stream-extractor">Stream extractor</a>.</p>
 118   </blockquote>
 119   <p><b>12. Binary I/O support that was investigated during development of the Endian
 120   library should be put up for mini-review for inclusion in the Boost I/O
 121   library.</b></p>
 122
 123 <blockquote>
 124   <p>Not done yet. Will be handled as a separate min-review soon after the
 125   Endian mini-review.</p>
 126
 127 </blockquote>
 128   <p><b>13. Other requested changes.</b></p>
 129
 130 <blockquote>
 131   <ul>
 132     <li>In addition to the named-endianness conversion functions, functions that perform
 133     compile-time (via template) and run-time (via function argument) dispatch
 134     are now provided.</li>
 135     <li><code>order::native</code> is now a synonym for <code>order::big</code>
 136   or <code>order::little</code> according to the endianness of the platform. This reduces the number of template specializations required.</li>
 137     <li>Headers have been reorganized to make them easier to read,
 138   with a synopsis at the front and implementation following.</li>
 139   </ul>
 140 </blockquote>
 141 <hr>
 142 <p>Last revised:
 143 <!--webbot bot="Timestamp" s-type="EDITED" s-format="%d %B, %Y" startspan -->19 January, 2015<!--webbot bot="Timestamp" endspan i-checksum="38903" --></p>
 144 <p>© Copyright Beman Dawes, 2014</p>
 145 <p>Distributed under the Boost Software License, Version 1.0. See
 146 <a href="http://www.boost.org/LICENSE_1_0.txt">www.boost.org/ LICENSE_1_0.txt</a></p>
 147
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