fixed dereferency sampler variable

Author: haoxian2

src/acl_kernel.cpp

@@ -419,7 +419,7 @@ CL_API_ENTRY cl_int CL_API_CALL clSetKernelArgIntelFPGA(cl_kernel kernel,
         ERR_RET(CL_INVALID_ARG_SIZE, context,
                 "Argument size is the wrong size");
       }
-    } else if (arg_size == sizeof(cl_mem) && arg_value!=NULL &&
+    } else if (arg_size == sizeof(cl_mem) && arg_value != NULL &&
                acl_pipe_is_valid_pointer(*((cl_mem *)arg_value), kernel)) {
       is_pipe = CL_TRUE;
     } else if (arg_size != arg_info->size) {
@@ -442,7 +442,8 @@ CL_API_ENTRY cl_int CL_API_CALL clSetKernelArgIntelFPGA(cl_kernel kernel,
     kernel->arg_defined[arg_index] = 1;
 
     /* If this is a host pipe, create a host channel and bind them together */
-    if (arg_info->host_accessible && pipe_ptr && pipe_ptr->host_pipe_info != NULL) {
+    if (arg_info->host_accessible && pipe_ptr &&
+        pipe_ptr->host_pipe_info != NULL) {
       if (pipe_ptr->host_pipe_info->m_binded_kernel != NULL) {
         ERR_RET(CL_INVALID_ARG_VALUE, context,
                 "This pipe has already been bound to a kernel. Cannot "
@@ -639,6 +640,7 @@ CL_API_ENTRY cl_int CL_API_CALL clSetKernelArgIntelFPGA(cl_kernel kernel,
         kernel->arg_is_ptr[arg_index] = CL_FALSE;
       } else if (is_sampler) {
         cl_sampler sampler = *(cl_sampler *)arg_value;
+        assert(sampler);
         int sampler_bitfield = 0;
 
         sampler_bitfield = 0;