sdk/1.0/docs/man/private.xml

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    <refentryinfo>
        <keywordset>
            <keyword>                            
                __private
            </keyword>
        </keywordset>
    </refentryinfo>

    <refmeta>                                    
        <refentrytitle>__private</refentrytitle>

        <refmiscinfo>
            <copyright>
                <year>2007-2009</year>
                <holder>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.</holder>
            </copyright>
        </refmiscinfo>
        <manvolnum>2</manvolnum>
    </refmeta>

<!-- ================================ SYNOPSIS -->

    <refnamediv id="__private">             
        <refname>__private</refname>

        <refpurpose>
            Address Space Qualifier.
        </refpurpose>
    </refnamediv>


    <!-- ALTERNATIVE SYNTAX SYNOPSIS (NON-FUNCTION) -->
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        <title>
        </title>

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                        <entry>
__private
private
                        </entry>
                    </row>
                </tbody>
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        </informaltable>
    </refsect2>


<!-- ================================ DESCRIPTION  -->

    <refsect1 id="description"><title>Description</title>
        <para>
OpenCL implements the following disjoint address spaces: <citerefentry href="global"><refentrytitle>__global</refentrytitle></citerefentry>, <citerefentry href="local"><refentrytitle>__local</refentrytitle></citerefentry>, <citerefentry href="constant"><refentrytitle>__constant</refentrytitle></citerefentry> and <function>__private</function>.
        <para>
        </para>
The address space qualifier may be used in variable declarations to specify the region of memory that is used to allocate the object. The C syntax for type qualifiers is extended in OpenCL to include an address space name as a valid type qualifier. If the type of an object is qualified by an address space name, the object is allocated in the specified address name; otherwise, the object is allocated in the generic address space.
        </para>

        <para>
The address space names without the __ prefix i.e. <function>global</function>, <function>local</function>, <function>constant</function> and <function>private</function> may be substituted for the corresponding address space names with the __ prefix.
        </para>

        <para>
The generic address space name for arguments to a function in a program, or local variables of a function is  <function>__private</function>. All arguments to a <function>__kernel</function> function shall be in the <function>__private</function> address space.
        </para>

        <para>
<citerefentry  href="functionQualifiers"><refentrytitle>__kernel</refentrytitle></citerefentry> function arguments declared to be a pointer of a type can point to one of the following address spaces only: <function>__global</function>, <function>__local</function> or <function>__constant</function>. A pointer to address space A can only be assigned to a pointer to the same address space A. Casting a pointer to address space A to a pointer to address space B is illegal.
        </para>

        <para>
The <function>__kernel</function> function arguments declared to be of type <type><citerefentry  href="otherDataTypes"><refentrytitle>image2d_t</refentrytitle></citerefentry></type> or <type><citerefentry  href="otherDataTypes"><refentrytitle>image3d_t</refentrytitle></citerefentry></type>
always point to the <function>__global</function> address space. All program scope variables must be declared in the <function>__constant</function> address space.
        </para>

        <para>
All variables inside a function (including <function>__kernel</function> functions),
or passed into the function as arguments are in the <function>__private</function> or <function>private</function> address space. Variables declared as pointers are considered to point to the <function>__private</function> address space if an address space qualifier is not specified except for arguments declared to be of type <type>image2d_t</type> and <type>image2d_t</type> which implicitly point to the <function>__global</function> address space.
        </para>

    </refsect1>


<!-- ================================ EXAMPLE  -->

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        <title>
            Example
        </title>

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// declares a pointer p in the __private address space that
// points to an int object in address space __global
__global int *p;

// declares an array of 4 floats in the __private address space.
float x[4];
                        </entry>
                    </row>
                </tbody>
            </tgroup>
        </informaltable>
    </refsect2>



<!-- ================================ SPECIFICATION  -->
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    <refsect1 id="specification"><title>Specification</title>
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            <olink uri="addressSpaceQualifier">OpenCL Specification</olink>
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<!-- ================================ ALSO SEE  -->

    <refsect1 id="seealso"><title>Also see</title>
        <para>
            <citerefentry href="global"><refentrytitle>__global</refentrytitle></citerefentry>, 
            <citerefentry href="local"><refentrytitle>__local</refentrytitle></citerefentry>, 
            <citerefentry href="constant"><refentrytitle>__constant</refentrytitle></citerefentry>
        </para>
    </refsect1>



<!-- ============================== COPYRIGHT -->
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