consistent text treatment for NULL

Author: bashbaug

api/opencl_runtime_layer.asciidoc

@@ -11950,16 +11950,16 @@ Otherwise, it returns one of the following errors:
     SVM or the required SVM capabilities for the SVM pointer.
   * {CL_INVALID_WORK_DIMENSION} if _work_dim_ is not a valid value (i.e. a
     value between 1 and {CL_DEVICE_MAX_WORK_ITEM_DIMENSIONS}).
-  * {CL_INVALID_GLOBAL_WORK_SIZE} if _global_work_size_ is NULL or if any of
-    the values specified in _global_work_size_ are 0.
+  * {CL_INVALID_GLOBAL_WORK_SIZE} if _global_work_size_ is `NULL` or if any of
+    the values specified in _global_work_size_ are zero.
   * {CL_INVALID_GLOBAL_WORK_SIZE} if any of the values specified in
     _global_work_size_ exceed the maximum value representable by `size_t` on
     the device associated with _command_queue_.
   * {CL_INVALID_GLOBAL_OFFSET} if the value specified in _global_work_size_
     plus the corresponding value in _global_work_offset_ for dimension
     exceeds the maximum value representable by `size_t` on the device
     associated with _command_queue_.
-  * {CL_INVALID_VALUE} if _suggested_local_work_size_ is NULL.
+  * {CL_INVALID_VALUE} if _suggested_local_work_size_ is `NULL`.
   * {CL_OUT_OF_RESOURCES} if there is a failure to allocate resources
     required by the OpenCL implementation on the device.
   * {CL_OUT_OF_HOST_MEMORY} if there is a failure to allocate resources
@@ -12119,7 +12119,7 @@ Otherwise, it returns one of the following errors:
     in _global_work_offset_ for any dimensions is greater than the maximum value
     representable by {size_t_TYPE} on the device associated with _command_queue_
   * {CL_INVALID_GLOBAL_WORK_SIZE}
-    ** if _global_work_size_ is NULL or if any of the values specified in
+    ** if _global_work_size_ is `NULL` or if any of the values specified in
     _global_work_size_[0], ... _global_work_size_[_work_dim_ - 1] are zero.
     This error condition does not apply when the device associated with
     _command_queue_ supports OpenCL 2.1 or newer.
@@ -13891,7 +13891,7 @@ be provided for semaphores created from
 {clEnqueueWaitSemaphoresKHR} and {clEnqueueSignalSemaphoresKHR} may return
 {CL_INVALID_VALUE} if _sema_objects_ list has one or more semaphores
 obtained from {CL_SEMAPHORE_HANDLE_D3D12_FENCE_KHR} and _sema_payload_list_
-is NULL.
+is `NULL`.
 
 endif::cl_khr_external_semaphore_dx_fence[]
 
@@ -16701,7 +16701,7 @@ one of the errors below is returned:
     _configs_ is not `NULL` and _num_configs_ is 0.
   * {CL_INVALID_VALUE} if any element of _config_types_ is not a valid
     {cl_command_buffer_update_type_khr_TYPE} enum.
-  * {CL_INVALID_VALUE} if any element of _configs_ is NULL.
+  * {CL_INVALID_VALUE} if any element of _configs_ is `NULL`.
   * {CL_OUT_OF_RESOURCES} if there is a failure to allocate resources
     required by the OpenCL implementation on the device.
   * {CL_OUT_OF_HOST_MEMORY} if there is a failure to allocate resources