GBE: don't enable double by default.

Actually, we don't support double completely currently.
Let's disable it now. This bring a little incompatible point with the 1.2 spec
which doesn't require the kernel to use the following pragma to enable fp64.
 #pragma OPENCL EXTENSION cl_khr_fp64 : enable

If the application wants to try the partially supported double with beignet
under opencl 1.2, the application will still need to add the above pragma.

Signed-off-by: Zhigang Gong <zhigang.gong@intel.com>
Reviewed-by: "Yang, Rong R" <rong.r.yang@intel.com>

1 files changed, 5 insertions, 1 deletions

diff --git a/backend/src/backend/program.cpp b/backend/src/backend/program.cpp
index b83e9ebd..d60835e2 100644
--- a/backend/src/backend/program.cpp
+++ b/backend/src/backend/program.cpp
@@ -807,10 +807,14 @@ namespace gbe {
       p = strstr(const_cast<char *>(options), "-cl-opt-disable");
       if (p)
         optLevel = 0;
-
+      // XXX enable cl_khr_fp64 may cause some potential bugs.
+      // we may need to revisit here latter when we want to support fp64 completely.
+      // For now, as we don't support fp64 actually, just disable it by default.
+#if 0
       #define ENABLE_CL_KHR_FP64_STR "#pragma OPENCL EXTENSION cl_khr_fp64 : enable\n"
       if (!strstr(const_cast<char *>(options), "-cl-std=CL1.1"))
         fwrite(ENABLE_CL_KHR_FP64_STR, strlen(ENABLE_CL_KHR_FP64_STR), 1, clFile);
+#endif
 
       clOpt += options;
     }