Exposed dpctl.SyclDevice.sub_group_sizes property

The property returns a vector of supported sub-group sizes.

The relationship to `SyclDevice.max_num_sub_groups` is not
clear at the moment.

Author: oleksandr-pavlyk

dpctl/_backend.pxd

@@ -204,6 +204,8 @@ cdef extern from "syclinterface/dpctl_sycl_device_interface.h":
     cdef uint64_t DPCTLDevice_GetGlobalMemCacheSize(const DPCTLSyclDeviceRef DRef)
     cdef _global_mem_cache_type DPCTLDevice_GetGlobalMemCacheType(
         const DPCTLSyclDeviceRef DRef)
+    cdef size_t *DPCTLDevice_GetSubGroupSizes(const DPCTLSyclDeviceRef DRef,
+        size_t *res_len)
 
 
 cdef extern from "syclinterface/dpctl_sycl_device_manager.h":

dpctl/_sycl_device.pyx

@@ -65,6 +65,7 @@ from ._backend cimport (  # noqa: E211
     DPCTLDevice_GetPreferredVectorWidthShort,
     DPCTLDevice_GetProfilingTimerResolution,
     DPCTLDevice_GetSubGroupIndependentForwardProgress,
+    DPCTLDevice_GetSubGroupSizes,
     DPCTLDevice_GetVendor,
     DPCTLDevice_HasAspect,
     DPCTLDevice_Hash,
@@ -884,6 +885,28 @@ cdef class SyclDevice(_SyclDevice):
             self._device_ref
         )
 
+    @property
+    def sub_group_sizes(self):
+        """ Returns list of supported sub-group sizes for this device.
+
+        Returns:
+            List[int]: List of supported sub-group sizes.
+        """
+        cdef size_t *sg_sizes = NULL
+        cdef size_t sg_sizes_len = 0
+        cdef size_t i
+
+        sg_sizes = DPCTLDevice_GetSubGroupSizes(
+            self._device_ref, &sg_sizes_len)
+        if (sg_sizes is not NULL and sg_sizes_len > 0):
+            res = list()
+            for i in range(sg_sizes_len):
+                res.append(sg_sizes[i])
+            DPCTLSize_t_Array_Delete(sg_sizes)
+            return res
+        else:
+           return []
+
     @property
     def sycl_platform(self):
         """ Returns the platform associated with this device.

dpctl/tests/_device_attributes_checks.py

@@ -115,6 +115,11 @@ def check_max_num_sub_groups(device):
         assert max_num_sub_groups > 0
 
 
+def check_sub_group_sizes(device):
+    sg_sizes = device.sub_group_sizes
+    assert all(el > 0 for el in sg_sizes)
+
+
 def check_has_aspect_host(device):
     try:
         device.has_aspect_host
@@ -605,6 +610,7 @@ def check_global_mem_cache_line_size(device):
     check_max_work_item_sizes,
     check_max_work_group_size,
     check_max_num_sub_groups,
+    check_sub_group_sizes,
     check_is_accelerator,
     check_is_cpu,
     check_is_gpu,