| <?xml version="1.0" encoding="UTF-8"?> |
| <!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook MathML Module V1.1b1//EN" |
| "http://www.oasis-open.org/docbook/xml/mathml/1.1CR1/dbmathml.dtd"> |
| <refentry> |
| <refentryinfo> |
| <keywordset> |
| <keyword>accessQualifiers</keyword> |
| </keywordset> |
| </refentryinfo> |
| |
| <refmeta> |
| <refentrytitle>accessQualifiers</refentrytitle> |
| |
| <refmiscinfo> |
| <copyright> |
| <year>2007-2013</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>3</manvolnum> |
| </refmeta> |
| |
| <!-- ================================ SYNOPSIS --> |
| |
| <refnamediv id="accessQualifiers"> |
| <refname>Access Qualifiers</refname> |
| |
| <refpurpose> |
| Access Qualifiers for image memory objects. |
| </refpurpose> |
| </refnamediv> |
| |
| <!-- ALTERNATIVE SYNTAX SYNOPSIS (NON-FUNCTION) --> |
| <refsect2 id="synopsis"> |
| <title> |
| </title> |
| |
| <informaltable frame="none"> |
| <tgroup cols="1" align="left" colsep="0" rowsep="0"> |
| <colspec colname="col1" colnum="1" /> |
| <tbody> |
| <row> |
| <entry> |
| __read_only |
| __write_only |
| __read_write |
| read_only |
| write_only |
| read_write |
| </entry> |
| </row> |
| </tbody> |
| </tgroup> |
| </informaltable> |
| </refsect2> |
| |
| <!-- ================================ DESCRIPTION --> |
| |
| <refsect1 id="description"><title>Description</title> |
| <para> |
| Image objects specified as arguments to a |
| kernel can be declared to be read-only, write-only or |
| read-write. The <function>__read_only</function> |
| (or <function>read_only</function>) and |
| <function>__write_only</function> |
| (or <function>write_only</function>) qualifiers must be used with |
| image object arguments to declare if the image |
| object is being read or written by a kernel or function. The |
| <function>__read_write</function> (or <function>read_write</function>) |
| qualifier must be used with image object arguments |
| of kernels and of user-defined functions to |
| declare if the image object is being both read and |
| written by the kernel. If no qualifier is provided, |
| <function>read_only</function> is assumed. |
| </para> |
| |
| <para> |
| In the following example |
| </para> |
| |
| <informaltable frame="none"> |
| <tgroup cols="1" align="left" colsep="0" rowsep="0"> |
| <colspec colname="col1" colnum="1" /> |
| <tbody> |
| <row> |
| <entry> |
| <literallayout>kernel void |
| foo (read_only image2d_t imageA, |
| write_only image2d_t imageB) |
| { |
| ... |
| } |
| </literallayout> |
| </entry> |
| </row> |
| </tbody> |
| </tgroup> |
| </informaltable> |
| |
| <para> |
| <code>imageA</code> is a read-only 2D image object, and |
| <code>imageB</code> is a write-only 2D image object. |
| </para> |
| |
| <para> |
| The sampler-less read image and write image built-ins |
| can be used with image declared with the |
| <function>__read_write</function> (or <function>read_write</function>) qualifier. |
| Calls to built-ins that read from an image |
| using a sampler for images declared with the |
| <function>__read_write</function> (or <function>read_write</function>) qualifier |
| will be a compilation error. |
| </para> |
| |
| <para> |
| Pipe objects specified as arguments to a kernel |
| also use these access qualifiers. Refer to |
| section 6.13.16 for a detailed description on |
| how these access qualifiers can be used with pipes. |
| </para> |
| </refsect1> |
| |
| <!-- ================================ NOTES --> |
| |
| <refsect1 id="notes"><title>Notes</title> |
| <para> |
| The <function>__read_only</function>, <function>__write_only</function>, |
| <function>__read_write</function>, <function>read_only</function>, |
| <function>write_only</function> and <function>read_write</function> names are reserved |
| for use as access qualifiers and shall not be used otherwise. |
| </para> |
| </refsect1> |
| |
| <!-- ================================ EXAMPLE --> |
| |
| <!-- |
| <refsect2 id="example1"> |
| <title> |
| Example |
| </title> |
| </refsect2> |
| --> |
| |
| <!-- ================================ SPECIFICATION --> |
| <!-- Set the "uri" attribute in the <olink /> element to the "named destination" for the PDF page |
| --> |
| <refsect1 id="specification"><title>Specification</title> |
| <para> |
| <imageobject> |
| <imagedata fileref="pdficon_small1.gif" format="gif" /> |
| </imageobject> |
| |
| <olink uri="accessQualifiers">OpenCL Specification</olink> |
| </para> |
| </refsect1> |
| |
| <!-- ================================ ALSO SEE --> |
| |
| <refsect1 id="seealso"><title>Also see</title> |
| <para> |
| <citerefentry><refentrytitle>qualifiers</refentrytitle></citerefentry>, |
| </para> |
| </refsect1> |
| |
| <!-- ============================== COPYRIGHT --> |
| <!-- Content included from copyright.inc.xsl --> |
| |
| <refsect3 id="Copyright"><title></title> |
| <imageobject> |
| <imagedata fileref="KhronosLogo.jpg" format="jpg" /> |
| </imageobject> |
| <para /> |
| </refsect3> |
| |
| <!-- 19-Oct-2015, C lang 2.0 rev 29 --> |
| </refentry> |
| |