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    <title>work_group_barrier</title>
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        <a xmlns="http://www.w3.org/1999/xhtml" id="work_group_barrier"></a>
        <h1>work_group_barrier</h1>
        <p>
            All work-items in a work-group executing the kernel on a processor must execute this function before any are allowed to continue execution beyond the work_group_barrier.
        </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">
                    <a class="link" href="scalarDataTypes.html" target="pagedisplay">void</a>
                    <strong class="fsfunc">
                        work_group_barrier
                    </strong>
                (</code>
                <td><a xmlns="http://www.w3.org/1999/xhtml" class="link" href="enums.html#cl_mem_fence_flags" target="pagedisplay">cl_mem_fence_flags</a> <var xmlns="http://www.w3.org/1999/xhtml" class="pdparam">flags</var><code>)</code></td>
              </td>
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        </div>
        <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">
                    <a class="link" href="scalarDataTypes.html" target="pagedisplay">void</a>
                    <strong class="fsfunc">
                        work_group_barrier
                    </strong>
                (</code>
                <td><a xmlns="http://www.w3.org/1999/xhtml" class="link" href="enums.html#cl_mem_fence_flags" target="pagedisplay">cl_mem_fence_flags</a> <var xmlns="http://www.w3.org/1999/xhtml" class="pdparam">flags</var>, </td>
              </td>
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              <td> </td>
              <td><a xmlns="http://www.w3.org/1999/xhtml" class="link" href="memory_scope.html" target="pagedisplay">memory_scope</a> <var xmlns="http://www.w3.org/1999/xhtml" class="pdparam">scope
</var><code>)</code></td>
            </tr>
          </table>
        </div>
      </div>
      <div class="refsect1">
        <a id="description"></a>
        <h2>Description</h2>
        <p>
            The built-in function <code class="function">barrier</code> 
            has been renamed <code class="function">work_group_barrier</code>. 
            For backward compatibility, <code class="function">barrier</code> is 
            also supported.
        </p>
        <p>
          All work-items in a work-group executing the kernel on a processor must execute
          this function before any are allowed to continue execution beyond the 
          <code class="function">work_group_barrier</code>.
          This function must be encountered by all work-items in a work-group executing the kernel.
            These rules apply to ND-ranges implemented with uniform and non-uniform 
            work-groups.
        </p>
        <p>
          If <code class="function">work_group_barrier</code> is inside a conditional statement, then all work-items
          must enter the conditional if any work-item enters the conditional statement and
          executes the <code class="function">work_group_barrier</code>.
        </p>
        <p>
          If <code class="function">work_group_barrier</code> is inside a loop, all work-items must execute the
          <code class="function">work_group_barrier</code> for each iteration of the loop before any are allowed
          to continue execution beyond the <code class="function">work_group_barrier</code>.
        </p>
        <p>
            The <code class="function">work_group_barrier</code> function also supports a 
            variant that specifies the memory scope. For the 
            <code class="function">work_group_barrier</code> variant that does not take a 
            memory scope, the <code class="varname">scope</code> is 
            <code class="code">memory_scope_work_group</code>.
        </p>
        <p>
            The <code class="varname">scope</code> argument specifies whether the memory 
            accesses of work-items in the work-group to 
            memory address space(s) identified by <code class="varname">flags</code> become 
            visible to all work-items in the work-group, the 
            device or all SVM devices. 
        </p>
        <p>
            The <code class="function">work_group_barrier</code> function can also be used 
            to specify which memory operations i.e. to global 
            memory, local memory or images become visible to 
            the appropriate memory scope identified by <code class="varname">scope</code>. 
            The <code class="varname">flags</code> argument specifies the memory address 
            spaces and can be set to 0 or a 
            combination of the following values ORed together.
            When these flags are OR’ed together the 
            <code class="function">work_group_barrier</code> acts as a combined barrier for 
            all address spaces specified by the flags ordering 
            memory accesses both within and across the 
            specified address spaces.
        </p>
        <p>
            <code class="constant">CLK_LOCAL_MEM_FENCE</code> - The 
            <code class="function">work_group_barrier</code> function will ensure that all 
            local memory accesses become visible to all 
            workitems in the work-group. Note that the value of 
            <code class="varname">scope</code> is ignored as the memory scope is always 
            <code class="code">memory_scope_work_group</code>.
        </p>
        <p>
            <code class="constant">CLK_GLOBAL_MEM_FENCE</code> – The 
            <code class="function">work_group_barrier</code> function ensure that all global 
            memory accesses become visible to the appropriate 
            scope as given by <code class="varname">scope</code>.
        </p>
        <p>
            <code class="constant">CLK_IMAGE_MEM_FENCE</code> – The 
            <code class="function">work_group_barrier</code> function will ensure that all 
            image memory accesses become visible to the 
            appropriate scope as given by <code class="varname">scope</code>. The value of 
            <code class="varname">scope</code> must be <code class="constant">memory_scope_work_group</code> or 
            <code class="constant">memory_scope_device</code>.
        </p>
        <p>
            The values of <code class="varname">flags</code> and 
            <code class="varname">scope</code> must be the same for
            all work-items in the work-group.
        </p>
      </div>
      <div class="refsect1">
        <a id="specification"></a>
        <h2>Specification</h2>
        <p>
            <img src="pdficon_small1.gif" />

            <a href="https://www.khronos.org/registry/cl/specs/opencl-2.1-openclc.pdf#page=97" target="OpenCL Spec">OpenCL Specification</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 © 2007-2015 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
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