Add support for OpenCL 1.1 sub-buffers.

5 files changed, 89 insertions, 6 deletions

diff --git a/config.tests/unix/opencl11/opencl11.cpp b/config.tests/unix/opencl11/opencl11.cpp
index 3290b2e..87692cb 100644
--- a/config.tests/unix/opencl11/opencl11.cpp
+++ b/config.tests/unix/opencl11/opencl11.cpp
@@ -47,14 +47,16 @@
 #include <CL/cl.h>
 #endif
 
-// Try to link against the function in the library, even if the
-// installed system header happens to be for OpenCL 1.0.
-#if !defined(CL_VERSION_1_1)
-extern cl_event clCreateUserEvent(cl_context, cl_int *);
-#endif
-
 int main(int, char **)
 {
     clCreateUserEvent(0, 0);
+
+    cl_buffer_region region;
+    region.origin = 0;
+    region.size = 0;
+    clCreateSubBuffer
+        (0, CL_MEM_READ_WRITE,
+         CL_BUFFER_CREATE_TYPE_REGION, &region, 0);
+
     return 0;
 }
diff --git a/doc/src/opencl11.qdoc b/doc/src/opencl11.qdoc
index 7d43078..000d98e 100644
--- a/doc/src/opencl11.qdoc
+++ b/doc/src/opencl11.qdoc
@@ -66,6 +66,10 @@
        created with QCLContext::createCommandQueue().
     \o New channel orders have been added to QCLImageFormat for
        the \c CL_Rx, \c CL_RGx, and \c CL_RGBx values.
+    \o Support for sub-buffers in QCLBuffer:
+       \l{QCLBuffer::createSubBuffer()}{createSubBuffer()},
+       \l{QCLBuffer::createSubBuffer()}{parentBuffer()}, and
+       \l{QCLBuffer::createSubBuffer()}{offset()}.
     \endlist
 
     \l{index.html}{Return to Home}
diff --git a/src/opencl/qclbuffer.cpp b/src/opencl/qclbuffer.cpp
index fb4d43b..6702be5 100644
--- a/src/opencl/qclbuffer.cpp
+++ b/src/opencl/qclbuffer.cpp
@@ -42,6 +42,7 @@
 #include "qclbuffer.h"
 #include "qclimage.h"
 #include "qclcontext.h"
+#include "qclext_p.h"
 
 QT_BEGIN_NAMESPACE
 
@@ -462,4 +463,68 @@ QCLEvent QCLBuffer::mapAsync
         return QCLEvent();
 }
 
+/*!
+    Creates a new buffer that refers to the \a size bytes,
+    starting at \a offset within this buffer.  The data in
+    the new buffer will be accessed according to \a access.
+
+    Sub-buffers are an OpenCL 1.1 feature.  On OpenCL 1.0,
+    this function will return a null buffer.
+
+    \sa parentBuffer(), offset()
+*/
+QCLBuffer QCLBuffer::createSubBuffer
+    (size_t offset, size_t size, QCLMemoryObject::Access access)
+{
+#ifdef QT_OPENCL_1_1
+    cl_int error;
+    cl_buffer_region region;
+    region.origin = offset;
+    region.size = size;
+    cl_mem mem = clCreateSubBuffer
+        (memoryId(), cl_mem_flags(access),
+         CL_BUFFER_CREATE_TYPE_REGION, &region, &error);
+    context()->reportError("QCLBuffer::createSubBuffer:", error);
+    return QCLBuffer(context(), mem);
+#else
+    Q_UNUSED(offset);
+    Q_UNUSED(size);
+    Q_UNUSED(access);
+    return QCLBuffer();
+#endif
+}
+
+/*!
+    Returns the parent of this buffer if it is a sub-buffer;
+    null otherwise.
+
+    \sa createSubBuffer(), offset()
+*/
+QCLBuffer QCLBuffer::parentBuffer() const
+{
+    cl_mem parent;
+    if (clGetMemObjectInfo(memoryId(), CL_MEM_ASSOCIATED_MEMOBJECT,
+                           sizeof(parent), &parent, 0) != CL_SUCCESS)
+        return QCLBuffer();
+    if (parent)
+        clRetainMemObject(parent);
+    return QCLBuffer(context(), parent);
+}
+
+/*!
+    Returns the offset of this buffer within its parentBuffer()
+    if it is a sub-buffer; zero otherwise.
+
+    \sa createSubBuffer(), parentBuffer()
+*/
+size_t QCLBuffer::offset() const
+{
+    size_t value;
+    if (clGetMemObjectInfo(memoryId(), CL_MEM_OFFSET,
+                           sizeof(value), &value, 0) != CL_SUCCESS)
+        return 0;
+    else
+        return value;
+}
+
 QT_END_NAMESPACE
diff --git a/src/opencl/qclbuffer.h b/src/opencl/qclbuffer.h
index 8c19dd6..4e9a561 100644
--- a/src/opencl/qclbuffer.h
+++ b/src/opencl/qclbuffer.h
@@ -102,6 +102,12 @@ public:
     QCLEvent mapAsync(void **ptr, size_t offset, size_t size,
                       QCLMemoryObject::Access access,
                       const QCLEventList &after = QCLEventList());
+
+    QCLBuffer createSubBuffer
+        (size_t offset, size_t size, QCLMemoryObject::Access access);
+
+    QCLBuffer parentBuffer() const;
+    size_t offset() const;
 };
 
 QT_END_NAMESPACE
diff --git a/src/opencl/qclext_p.h b/src/opencl/qclext_p.h
index b881393..68a17b7 100644
--- a/src/opencl/qclext_p.h
+++ b/src/opencl/qclext_p.h
@@ -84,6 +84,12 @@
 #ifndef CL_COMMAND_USER
 #define CL_COMMAND_USER 0x1204
 #endif
+#ifndef CL_MEM_ASSOCIATED_MEMOBJECT
+#define CL_MEM_ASSOCIATED_MEMOBJECT 0x1107
+#endif
+#ifndef CL_MEM_OFFSET
+#define CL_MEM_OFFSET 0x1108
+#endif
 
 // OpenCL-OpenGL sharing.
 #ifndef CL_INVALID_CL_SHAREGROUP_REFERENCE_KHR