<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "https://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/xhtml;charset=UTF-8"/>
<meta http-equiv="X-UA-Compatible" content="IE=9"/>
<meta name="generator" content="Doxygen 1.8.15"/>
<meta name="viewport" content="width=device-width, initial-scale=1"/>
<title>My Project: SDL_bits.h Source File</title>
<link href="tabs.css" rel="stylesheet" type="text/css"/>
<script type="text/javascript" src="jquery.js"></script>
<script type="text/javascript" src="dynsections.js"></script>
<link href="search/search.css" rel="stylesheet" type="text/css"/>
<script type="text/javascript" src="search/searchdata.js"></script>
<script type="text/javascript" src="search/search.js"></script>
<link href="doxygen.css" rel="stylesheet" type="text/css" />
</head>
<body>
<div id="top"><!-- do not remove this div, it is closed by doxygen! -->
<div id="titlearea">
<table cellspacing="0" cellpadding="0">
<tbody>
<tr style="height: 56px;">
<td id="projectalign" style="padding-left: 0.5em;">
<div id="projectname">My Project
</div>
</td>
</tr>
</tbody>
</table>
</div>
<!-- end header part -->
<!-- Generated by Doxygen 1.8.15 -->
<script type="text/javascript">
/* @license magnet:?xt=urn:btih:cf05388f2679ee054f2beb29a391d25f4e673ac3&dn=gpl-2.0.txt GPL-v2 */
var searchBox = new SearchBox("searchBox", "search",false,'Search');
/* @license-end */
</script>
<script type="text/javascript" src="menudata.js"></script>
<script type="text/javascript" src="menu.js"></script>
<script type="text/javascript">
/* @license magnet:?xt=urn:btih:cf05388f2679ee054f2beb29a391d25f4e673ac3&dn=gpl-2.0.txt GPL-v2 */
$(function() {
initMenu('',true,false,'search.php','Search');
$(document).ready(function() { init_search(); });
});
/* @license-end */</script>
<div id="main-nav"></div>
</div><!-- top -->
<!-- window showing the filter options -->
<div id="MSearchSelectWindow"
onmouseover="return searchBox.OnSearchSelectShow()"
onmouseout="return searchBox.OnSearchSelectHide()"
onkeydown="return searchBox.OnSearchSelectKey(event)">
</div>
<!-- iframe showing the search results (closed by default) -->
<div id="MSearchResultsWindow">
<iframe src="javascript:void(0)" frameborder="0"
name="MSearchResults" id="MSearchResults">
</iframe>
</div>
<div class="header">
<div class="headertitle">
<div class="title">SDL_bits.h</div> </div>
</div><!--header-->
<div class="contents">
<a href="SDL__bits_8h.html">Go to the documentation of this file.</a><div class="fragment"><div class="line"><a name="l00001"></a><span class="lineno"> 1</span> <span class="comment">/*</span></div><div class="line"><a name="l00002"></a><span class="lineno"> 2</span> <span class="comment"> Simple DirectMedia Layer</span></div><div class="line"><a name="l00003"></a><span class="lineno"> 3</span> <span class="comment"> Copyright (C) 1997-2019 Sam Lantinga <slouken@libsdl.org></span></div><div class="line"><a name="l00004"></a><span class="lineno"> 4</span> <span class="comment"></span></div><div class="line"><a name="l00005"></a><span class="lineno"> 5</span> <span class="comment"> This software is provided 'as-is', without any express or implied</span></div><div class="line"><a name="l00006"></a><span class="lineno"> 6</span> <span class="comment"> warranty. In no event will the authors be held liable for any damages</span></div><div class="line"><a name="l00007"></a><span class="lineno"> 7</span> <span class="comment"> arising from the use of this software.</span></div><div class="line"><a name="l00008"></a><span class="lineno"> 8</span> <span class="comment"></span></div><div class="line"><a name="l00009"></a><span class="lineno"> 9</span> <span class="comment"> Permission is granted to anyone to use this software for any purpose,</span></div><div class="line"><a name="l00010"></a><span class="lineno"> 10</span> <span class="comment"> including commercial applications, and to alter it and redistribute it</span></div><div class="line"><a name="l00011"></a><span class="lineno"> 11</span> <span class="comment"> freely, subject to the following restrictions:</span></div><div class="line"><a name="l00012"></a><span class="lineno"> 12</span> <span class="comment"></span></div><div class="line"><a name="l00013"></a><span class="lineno"> 13</span> <span class="comment"> 1. The origin of this software must not be misrepresented; you must not</span></div><div class="line"><a name="l00014"></a><span class="lineno"> 14</span> <span class="comment"> claim that you wrote the original software. If you use this software</span></div><div class="line"><a name="l00015"></a><span class="lineno"> 15</span> <span class="comment"> in a product, an acknowledgment in the product documentation would be</span></div><div class="line"><a name="l00016"></a><span class="lineno"> 16</span> <span class="comment"> appreciated but is not required.</span></div><div class="line"><a name="l00017"></a><span class="lineno"> 17</span> <span class="comment"> 2. Altered source versions must be plainly marked as such, and must not be</span></div><div class="line"><a name="l00018"></a><span class="lineno"> 18</span> <span class="comment"> misrepresented as being the original software.</span></div><div class="line"><a name="l00019"></a><span class="lineno"> 19</span> <span class="comment"> 3. This notice may not be removed or altered from any source distribution.</span></div><div class="line"><a name="l00020"></a><span class="lineno"> 20</span> <span class="comment">*/</span></div><div class="line"><a name="l00021"></a><span class="lineno"> 21</span> </div><div class="line"><a name="l00028"></a><span class="lineno"> 28</span> <span class="preprocessor">#ifndef SDL_bits_h_</span></div><div class="line"><a name="l00029"></a><span class="lineno"> 29</span> <span class="preprocessor">#define SDL_bits_h_</span></div><div class="line"><a name="l00030"></a><span class="lineno"> 30</span> </div><div class="line"><a name="l00031"></a><span class="lineno"> 31</span> <span class="preprocessor">#include "<a class="code" href="SDL__stdinc_8h.html">SDL_stdinc.h</a>"</span></div><div class="line"><a name="l00032"></a><span class="lineno"> 32</span> </div><div class="line"><a name="l00033"></a><span class="lineno"> 33</span> <span class="preprocessor">#include "<a class="code" href="begin__code_8h.html">begin_code.h</a>"</span></div><div class="line"><a name="l00034"></a><span class="lineno"> 34</span> <span class="comment">/* Set up for C function definitions, even when using C++ */</span></div><div class="line"><a name="l00035"></a><span class="lineno"> 35</span> <span class="preprocessor">#ifdef __cplusplus</span></div><div class="line"><a name="l00036"></a><span class="lineno"> 36</span> <span class="keyword">extern</span> <span class="stringliteral">"C"</span> {</div><div class="line"><a name="l00037"></a><span class="lineno"> 37</span> <span class="preprocessor">#endif</span></div><div class="line"><a name="l00038"></a><span class="lineno"> 38</span> </div><div class="line"><a name="l00050"></a><span class="lineno"> 50</span> <span class="preprocessor">#if defined(__WATCOMC__) && defined(__386__)</span></div><div class="line"><a name="l00051"></a><span class="lineno"> 51</span> <span class="keyword">extern</span> _inline <span class="keywordtype">int</span> _SDL_clz_watcom (Uint32);</div><div class="line"><a name="l00052"></a><span class="lineno"> 52</span> <span class="preprocessor">#pragma aux _SDL_clz_watcom = \</span></div><div class="line"><a name="l00053"></a><span class="lineno"> 53</span> <span class="preprocessor"> "bsr eax, eax" \</span></div><div class="line"><a name="l00054"></a><span class="lineno"> 54</span> <span class="preprocessor"> "xor eax, 31" \</span></div><div class="line"><a name="l00055"></a><span class="lineno"> 55</span> <span class="preprocessor"> parm [eax] nomemory \</span></div><div class="line"><a name="l00056"></a><span class="lineno"> 56</span> <span class="preprocessor"> value [eax] \</span></div><div class="line"><a name="l00057"></a><span class="lineno"> 57</span> <span class="preprocessor"> modify exact [eax] nomemory;</span></div><div class="line"><a name="l00058"></a><span class="lineno"> 58</span> <span class="preprocessor">#endif</span></div><div class="line"><a name="l00059"></a><span class="lineno"> 59</span> </div><div class="line"><a name="l00060"></a><span class="lineno"> 60</span> SDL_FORCE_INLINE <span class="keywordtype">int</span></div><div class="line"><a name="l00061"></a><span class="lineno"><a class="line" href="SDL__bits_8h.html#ada8cd16089cc635936dfe1a6884729a4"> 61</a></span> <a class="code" href="SDL__bits_8h.html#ada8cd16089cc635936dfe1a6884729a4">SDL_MostSignificantBitIndex32</a>(Uint32 x)</div><div class="line"><a name="l00062"></a><span class="lineno"> 62</span> {</div><div class="line"><a name="l00063"></a><span class="lineno"> 63</span> <span class="preprocessor">#if defined(__GNUC__) && (__GNUC__ >= 4 || (__GNUC__ == 3 && __GNUC_MINOR__ >= 4))</span></div><div class="line"><a name="l00064"></a><span class="lineno"> 64</span>  <span class="comment">/* Count Leading Zeroes builtin in GCC.</span></div><div class="line"><a name="l00065"></a><span class="lineno"> 65</span> <span class="comment"> * http://gcc.gnu.org/onlinedocs/gcc-4.3.4/gcc/Other-Builtins.html</span></div><div class="line"><a name="l00066"></a><span class="lineno"> 66</span> <span class="comment"> */</span></div><div class="line"><a name="l00067"></a><span class="lineno"> 67</span>  <span class="keywordflow">if</span> (x == 0) {</div><div class="line"><a name="l00068"></a><span class="lineno"> 68</span>  <span class="keywordflow">return</span> -1;</div><div class="line"><a name="l00069"></a><span class="lineno"> 69</span>  }</div><div class="line"><a name="l00070"></a><span class="lineno"> 70</span>  <span class="keywordflow">return</span> 31 - __builtin_clz(x);</div><div class="line"><a name="l00071"></a><span class="lineno"> 71</span> <span class="preprocessor">#elif defined(__WATCOMC__) && defined(__386__)</span></div><div class="line"><a name="l00072"></a><span class="lineno"> 72</span>  <span class="keywordflow">if</span> (x == 0) {</div><div class="line"><a name="l00073"></a><span class="lineno"> 73</span>  <span class="keywordflow">return</span> -1;</div><div class="line"><a name="l00074"></a><span class="lineno"> 74</span>  }</div><div class="line"><a name="l00075"></a><span class="lineno"> 75</span>  <span class="keywordflow">return</span> 31 - _SDL_clz_watcom(x);</div><div class="line"><a name="l00076"></a><span class="lineno"> 76</span> <span class="preprocessor">#else</span></div><div class="line"><a name="l00077"></a><span class="lineno"> 77</span>  <span class="comment">/* Based off of Bit Twiddling Hacks by Sean Eron Anderson</span></div><div class="line"><a name="l00078"></a><span class="lineno"> 78</span> <span class="comment"> * <seander@cs.stanford.edu>, released in the public domain.</span></div><div class="line"><a name="l00079"></a><span class="lineno"> 79</span> <span class="comment"> * http://graphics.stanford.edu/~seander/bithacks.html#IntegerLog</span></div><div class="line"><a name="l00080"></a><span class="lineno"> 80</span> <span class="comment"> */</span></div><div class="line"><a name="l00081"></a><span class="lineno"> 81</span>  <span class="keyword">const</span> Uint32 b[] = {0x2, 0xC, 0xF0, 0xFF00, 0xFFFF0000};</div><div class="line"><a name="l00082"></a><span class="lineno"> 82</span>  <span class="keyword">const</span> <span class="keywordtype">int</span> S[] = {1, 2, 4, 8, 16};</div><div class="line"><a name="l00083"></a><span class="lineno"> 83</span> </div><div class="line"><a name="l00084"></a><span class="lineno"> 84</span>  <span class="keywordtype">int</span> msbIndex = 0;</div><div class="line"><a name="l00085"></a><span class="lineno"> 85</span>  <span class="keywordtype">int</span> i;</div><div class="line"><a name="l00086"></a><span class="lineno"> 86</span> </div><div class="line"><a name="l00087"></a><span class="lineno"> 87</span>  <span class="keywordflow">if</span> (x == 0) {</div><div class="line"><a name="l00088"></a><span class="lineno"> 88</span>  <span class="keywordflow">return</span> -1;</div><div class="line"><a name="l00089"></a><span class="lineno"> 89</span>  }</div><div class="line"><a name="l00090"></a><span class="lineno"> 90</span> </div><div class="line"><a name="l00091"></a><span class="lineno"> 91</span>  <span class="keywordflow">for</span> (i = 4; i >= 0; i--)</div><div class="line"><a name="l00092"></a><span class="lineno"> 92</span>  {</div><div class="line"><a name="l00093"></a><span class="lineno"> 93</span>  <span class="keywordflow">if</span> (x & b[i])</div><div class="line"><a name="l00094"></a><span class="lineno"> 94</span>  {</div><div class="line"><a name="l00095"></a><span class="lineno"> 95</span>  x >>= S[i];</div><div class="line"><a name="l00096"></a><span class="lineno"> 96</span>  msbIndex |= S[i];</div><div class="line"><a name="l00097"></a><span class="lineno"> 97</span>  }</div><div class="line"><a name="l00098"></a><span class="lineno"> 98</span>  }</div><div class="line"><a name="l00099"></a><span class="lineno"> 99</span> </div><div class="line"><a name="l00100"></a><span class="lineno"> 100</span>  <span class="keywordflow">return</span> msbIndex;</div><div class="line"><a name="l00101"></a><span class="lineno"> 101</span> <span class="preprocessor">#endif</span></div><div class="line"><a name="l00102"></a><span class="lineno"> 102</span> }</div><div class="line"><a name="l00103"></a><span class="lineno"> 103</span> </div><div class="line"><a name="l00104"></a><span class="lineno"> 104</span> SDL_FORCE_INLINE SDL_bool</div><div class="line"><a name="l00105"></a><span class="lineno"> 105</span> SDL_HasExactlyOneBitSet32(Uint32 x)</div><div class="line"><a name="l00106"></a><span class="lineno"> 106</span> {</div><div class="line"><a name="l00107"></a><span class="lineno"> 107</span>  <span class="keywordflow">if</span> (x && !(x & (x - 1))) {</div><div class="line"><a name="l00108"></a><span class="lineno"> 108</span>  <span class="keywordflow">return</span> SDL_TRUE;</div><div class="line"><a name="l00109"></a><span class="lineno"> 109</span>  }</div><div class="line"><a name="l00110"></a><span class="lineno"> 110</span>  <span class="keywordflow">return</span> SDL_FALSE;</div><div class="line"><a name="l00111"></a><span class="lineno"> 111</span> }</div><div class="line"><a name="l00112"></a><span class="lineno"> 112</span> </div><div class="line"><a name="l00113"></a><span class="lineno"> 113</span> <span class="comment">/* Ends C function definitions when using C++ */</span></div><div class="line"><a name="l00114"></a><span class="lineno"> 114</span> <span class="preprocessor">#ifdef __cplusplus</span></div><div class="line"><a name="l00115"></a><span class="lineno"> 115</span> }</div><div class="line"><a name="l00116"></a><span class="lineno"> 116</span> <span class="preprocessor">#endif</span></div><div class="line"><a name="l00117"></a><span class="lineno"> 117</span> <span class="preprocessor">#include "<a class="code" href="close__code_8h.html">close_code.h</a>"</span></div><div class="line"><a name="l00118"></a><span class="lineno"> 118</span> </div><div class="line"><a name="l00119"></a><span class="lineno"> 119</span> <span class="preprocessor">#endif </span><span class="comment">/* SDL_bits_h_ */</span><span class="preprocessor"></span></div><div class="line"><a name="l00120"></a><span class="lineno"> 120</span> </div><div class="line"><a name="l00121"></a><span class="lineno"> 121</span> <span class="comment">/* vi: set ts=4 sw=4 expandtab: */</span></div><div class="ttc" id="begin__code_8h_html"><div class="ttname"><a href="begin__code_8h.html">begin_code.h</a></div></div>
<div class="ttc" id="SDL__stdinc_8h_html"><div class="ttname"><a href="SDL__stdinc_8h.html">SDL_stdinc.h</a></div></div>
<div class="ttc" id="close__code_8h_html"><div class="ttname"><a href="close__code_8h.html">close_code.h</a></div></div>
<div class="ttc" id="SDL__bits_8h_html_ada8cd16089cc635936dfe1a6884729a4"><div class="ttname"><a href="SDL__bits_8h.html#ada8cd16089cc635936dfe1a6884729a4">SDL_MostSignificantBitIndex32</a></div><div class="ttdeci">SDL_FORCE_INLINE int SDL_MostSignificantBitIndex32(Uint32 x)</div><div class="ttdef"><b>Definition:</b> SDL_bits.h:61</div></div>
</div><!-- fragment --></div><!-- contents -->
<!-- start footer part -->
<hr class="footer"/><address class="footer"><small>
Generated by  <a href="http://www.doxygen.org/index.html">
<img class="footer" src="doxygen.png" alt="doxygen"/>
</a> 1.8.15
</small></address>
</body>
</html>
distrib
>
Mageia
>
7
>
armv7hl
>
media
>
core-updates
>
by-pkgid
>
bf9e3bc1aec7873c087fb2ccd927873f
>
files
>
11
