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    <title>hadd, rhadd</title>
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        <a xmlns="http://www.w3.org/1999/xhtml" id="hadd"></a>
        <h1>hadd, rhadd</h1>
        <p>
            Returns (<code xmlns="http://www.w3.org/1999/xhtml" class="varname">x</code> + <code xmlns="http://www.w3.org/1999/xhtml" class="varname">y</code>) &gt;&gt; 1, or (<code xmlns="http://www.w3.org/1999/xhtml" class="varname">x</code> + <code xmlns="http://www.w3.org/1999/xhtml" class="varname">y</code> + 1) &gt;&gt; 1
        </p>
      </div>
      <div class="refsynopsisdiv">
        <h2></h2>
        <div class="funcsynopsis">
          <table xmlns="" border="0" summary="Function synopsis" cellspacing="0" cellpadding="0">
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              <td>
                <code xmlns="http://www.w3.org/1999/xhtml" class="funcdef">
                    gentype
                    <strong class="fsfunc">                   
                        hadd
                    </strong>
                (</code>
                <td>gentype <var xmlns="http://www.w3.org/1999/xhtml" class="pdparam">x</var>, </td>
              </td>
            </tr>
            <tr valign="top">
              <td> </td>
              <td>gentype <var xmlns="http://www.w3.org/1999/xhtml" class="pdparam">y</var><code>)</code></td>
            </tr>
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        <div class="funcsynopsis">
          <table xmlns="" border="0" summary="Function synopsis" cellspacing="0" cellpadding="0">
            <tr valign="bottom">
              <td>
                <code xmlns="http://www.w3.org/1999/xhtml" class="funcdef">
                    gentype
                    <strong class="fsfunc">                   
                        rhadd
                    </strong>
                (</code>
                <td>gentype <var xmlns="http://www.w3.org/1999/xhtml" class="pdparam">x</var>, </td>
              </td>
            </tr>
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              <td> </td>
              <td>gentype <var xmlns="http://www.w3.org/1999/xhtml" class="pdparam">y</var><code>)</code></td>
            </tr>
          </table>
        </div>
      </div>
      <div class="refsect1">
        <a id="description"></a>
        <h2>Description</h2>
        <p>
			<code class="function">hadd</code> returns (<code class="varname">x</code>+<code class="varname">y</code>) &gt;&gt; 1. The intermediate sum does not modulo overflow.
		</p>
        <p>
			<code class="function">rhadd</code> returns (<code class="varname">x</code>+<code class="varname">y</code>+1) &gt;&gt; 1. The intermediate sum does not modulo overflow. 
		</p>
      </div>
      <div class="refsect1">
        <a id="notes"></a>
        <h2>Notes</h2>
        <p>
		Frequently vector operations need n + 1 bits temporarily to calculate a result. The <code class="function">rhadd</code> instruction gives you an extra bit without needing to upsample and downsample. This can be a profound performance win.
		</p>
        <p>
			Built-in integer functions can be used to take scalar or vector arguments. We use
the generic type name <span class="type">gentype</span> to indicate that the function can take <span class="type">char</span>, <span class="type">char{2|4|8|16}</span>, <span class="type">uchar</span>, <span class="type">uchar{2|4|8|16}</span>, <span class="type">short</span>, <span class="type">short{2|4|8|16}</span>, <span class="type">ushort</span>, <span class="type">ushort{2|4|8|16}</span>, <span class="type">int</span>, <span class="type">int{2|4|8|16}</span>, <span class="type">uint</span>,
<span class="type">uint{2|4|8|16}</span>, <span class="type">long</span>, <span class="type">long{2|4|8|16}</span>, <span class="type">ulong</span>, or <span class="type">ulong{2|4|8|16}</span> as
the type for the arguments. We use the generic type name <span class="type">ugentype</span> to refer to unsigned
versions of <span class="type">gentype</span>. For example, if <span class="type">gentype</span> is <span class="type">char4</span>, <span class="type">ugentype</span> is <code class="constant">uchar4</code>.</p>
        <p>For any specific use of a function, the actual type has to be the same for all arguments and the return type unless otherwise specified.
        </p>
      </div>
      <div class="refsect1">
        <a id="specification"></a>
        <h2>Specification</h2>
        <p>
            <img src="pdficon_small1.gif" />
                                                 
            <a href="http://www.khronos.org/registry/cl/specs/opencl-1.x-latest.pdf#page=177" target="OpenCL Spec">OpenCL Specification</a>
        </p>
      </div>
      <div class="refsect1">
        <a id="seealso"></a>
        <h2>Also see</h2>
        <p>
            <a class="citerefentry" href="integerFunctions.html"><span class="citerefentry"><span class="refentrytitle">Integer Functions</span></span></a> 
        </p>
      </div>
      <div xmlns="" class="refsect3" lang="en" xml:lang="en"><a xmlns="http://www.w3.org/1999/xhtml" id="Copyright"></a><h4 xmlns="http://www.w3.org/1999/xhtml"></h4><img xmlns="http://www.w3.org/1999/xhtml" src="KhronosLogo.jpg" /><p xmlns="http://www.w3.org/1999/xhtml"></p>Copyright © 2007-2009 The Khronos Group Inc. 
Permission is hereby granted, free of charge, to any person obtaining a
copy of this software and/or associated documentation files (the
"Materials"), to deal in the Materials without restriction, including
without limitation the rights to use, copy, modify, merge, publish,
distribute, sublicense, and/or sell copies of the Materials, and to
permit persons to whom the Materials are furnished to do so, subject to
the condition that this copyright notice and permission notice shall be included
in all copies or substantial portions of the Materials. 
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