Use clew from clcc to allow run-time loading of opencl drivers.

Change-Id: I9f6ce113d637dbec069caa86b32459e2001ec0a0

sc/Library_scopencl.mk

@@ -27,11 +27,16 @@ $(eval $(call gb_Library_use_libraries,scopencl,\
 	$(gb_UWINAPI) \
 ))
 
-$(eval $(call gb_Library_use_externals,scopencl,opencl))
-
 $(eval $(call gb_Library_add_exception_objects,scopencl,\
 	sc/source/core/opencl/formulagroupcl \
 	sc/source/core/opencl/openclwrapper \
+	sc/source/core/opencl/clcc/clew \
+))
+
+ifeq ($(OS),LINUX)
+$(eval $(call gb_Library_add_libs,scopencl,\
+	-ldl \
 ))
+endif
 
 # vim: set noet sw=4 ts=4:

sc/source/core/opencl/openclwrapper.cxx

@@ -707,7 +707,10 @@ int OpenclDevice::runKernel( const char *kernelName, void **userdata)
 
 int OpenclDevice::initOpenclRunEnv( int argc )
 {
-    int status = 0;
+    int status = clewInit("/opt/AMDAPP/lib/x86_64/libOpenCL.so");
+    if (status < 0)
+        return 1;
+
     if ( MAX_CLKERNEL_NUM <= 0 )
     {
         return 1;

sc/source/core/opencl/openclwrapper.hxx

@@ -14,11 +14,8 @@
 #include <formula/opcode.hxx>
 #include <sal/detail/log.h>
 #include <cassert>
-#ifdef __APPLE__
-#include <OpenCL/cl.h>
-#else
-#include <CL/cl.h>
-#endif
+
+#include "clcc/clew.h"
 
 // CL_MAP_WRITE_INVALIDATE_REGION is new in OpenCL 1.2.