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| <font size="6">Endian </font></b><font size="6"><b>Mini-Review</b></font></td> |
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| <td><b> |
| <a href="index.html">Endian Home</a> |
| <a href="conversion.html">Conversion Functions</a> |
| <a href="arithmetic.html">Arithmetic Types</a> |
| <a href="buffers.html">Buffer Types</a> |
| <a href="choosing_approach.html">Choosing Approach</a></b></td> |
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| <p></p> |
| |
| <p>The results of the Boost.Endian formal review included a list of issues to be |
| resolved before a mini-review.</p> |
| |
| <p>The issues are shown in <b>bold</b> below, with the resolution indicated.</p> |
| |
| <p><b>1. Common use case scenarios should be developed.</b></p> |
| <blockquote> |
| |
| <p>Done. The documentation have been refactored. A page is now devoted to |
| <a href="choosing_approach.html">Choosing the Approach</a> to endianness. See |
| <a href="choosing_approach.html#Use-cases">Use cases</a> for use case |
| scenarios.</p> |
| </blockquote> |
| <p><b>2. Example programs should be developed for the common use case scenarios.</b></p> |
| <blockquote> |
| <p>Done. See <a href="choosing_approach.html">Choosing the Approach</a>. |
| Example code has been added throughout.</p> |
| </blockquote> |
| <p><b>3. Documentation should illuminate the differences between endian |
| integer/float type and endian conversion approaches to the common use |
| case scenarios, and provide guidelines for choosing the most appropriate |
| approach in user's applications.</b></p> |
| <blockquote> |
| <p>Done. See <a href="choosing_approach.html">Choosing the Approach</a>.</p> |
| </blockquote> |
| <p><b>4 .Conversion functions supplying results via return should be provided.</b></p> |
| <blockquote> |
| <p>Done. See <a href="conversion.html">ConversionFunctions</a>.</p> |
| </blockquote> |
| <p><b>5. Platform specific performance enhancements such as use of compiler intrinsics or relaxed alignment requirements should be supported.</b></p> |
| <blockquote> |
| <p>Done. Compiler (Clang, GCC, VisualC++, etc.) intrinsics and built-in |
| functions are used in the implementation where appropriate, as requested. See |
| <a href="index.html#Intrinsic">Built-in support for Intrinsics</a>. See |
| <a href="index.html#Timings">Timings for Example 2</a> to gauge the impact of |
| intrinsics.</p> |
| </blockquote> |
| <p><b>6. Endian integer (and floating) types should be implemented via the |
| conversion functions. If that can't be done efficiently, consideration |
| should be given to expanding the conversion function signatures to |
| resolve the inefficiencies.</b></p> |
| <blockquote> |
| <p>Done. For the endian types, the implementation uses the endian conversion |
| functions, and thus the intrinsics, as requested.</p> |
| </blockquote> |
| <p><b>7. Benchmarks that measure performance should be provided. It should be |
| possible to compare platform specific performance enhancements against |
| portable base implementations, and to compare endian integer approaches |
| against endian conversion approaches for the common use case scenarios.</b></p> |
| <blockquote> |
| <p>Done. See <a href="index.html#Timings">Timings for Example 2</a>. The <code>endian/test</code> directory |
| also contains several additional benchmark and speed test programs.</p> |
| </blockquote> |
| <p><b>8. Float (32-bits) and double (64-bits) should be supported. IEEE 754 is |
| the primary use case.</b></p> |
| <blockquote> |
| <p>Done. The <a href="buffers.html">endian buffer types</a>, |
| <a href="arithmetic.html">endian arithmetic types</a> and |
| <a href="conversion.html">endian conversion functions</a> now support 32-bit (<code>float)</code> |
| and 64-bit <code>(double)</code> floating point, as requested.</p> |
| </blockquote> |
| <p><b>9. Support for user defined types (UDTs) is desirable, and should be |
| provided where there would be no conflict with the other concerns.</b></p> |
| <blockquote> |
| <p>Done. See <a href="conversion.html#Customization-points">Customization |
| points for user-defined types (UDTs)</a>.</p> |
| </blockquote> |
| <p><b>10. There is some concern that endian integer/float arithmetic operations |
| might used inadvertently or inappropriately. The impact of adding an endian_buffer |
| class without arithmetic operations should be investigated.</b></p> |
| <blockquote> |
| <p>Done. The endian types have been decomposed into class template <code> |
| <a href="buffers.html">endian_buffer</a></code> and class template <code> |
| <a href="arithmetic.html">endian_arithmetic</a></code>. Class |
| <code>endian_buffer</code> is a public base class for <code>endian_arithmetic</code>, |
| and can also be used by users as a stand-alone class.</p> |
| </blockquote> |
| <p><b>11. Stream insertion and extraction of the endian integer/float types should |
| be documented and included in the test coverage.</b></p> |
| <blockquote> |
| <p>Done. See <a href="buffers.html#Stream-inserter">Stream inserter</a> and |
| <a href="buffers.html#Stream-extractor">Stream extractor</a>.</p> |
| </blockquote> |
| <p><b>12. Binary I/O support that was investigated during development of the Endian |
| library should be put up for mini-review for inclusion in the Boost I/O |
| library.</b></p> |
| |
| <blockquote> |
| <p>Not done yet. Will be handled as a separate min-review soon after the |
| Endian mini-review.</p> |
| |
| </blockquote> |
| <p><b>13. Other requested changes.</b></p> |
| |
| <blockquote> |
| <ul> |
| <li>In addition to the named-endianness conversion functions, functions that perform |
| compile-time (via template) and run-time (via function argument) dispatch |
| are now provided.</li> |
| <li><code>order::native</code> is now a synonym for <code>order::big</code> |
| or <code>order::little</code> according to the endianness of the platform. This reduces the number of template specializations required.</li> |
| <li>Headers have been reorganized to make them easier to read, |
| with a synopsis at the front and implementation following.</li> |
| </ul> |
| </blockquote> |
| <hr> |
| <p>Last revised: |
| <!--webbot bot="Timestamp" s-type="EDITED" s-format="%d %B, %Y" startspan -->19 January, 2015<!--webbot bot="Timestamp" endspan i-checksum="38903" --></p> |
| <p>© Copyright Beman Dawes, 2014</p> |
| <p>Distributed under the Boost Software License, Version 1.0. See |
| <a href="http://www.boost.org/LICENSE_1_0.txt">www.boost.org/ LICENSE_1_0.txt</a></p> |
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