[SYCL] Fix handling of subgroup info queries (#8859)

Update `opencl` PI plugin info queries to prevent crashes when the
device does not support subgroups.

---------

Signed-off-by: Michael Aziz <[email protected]>

Author: 0x12CC

sycl/plugins/opencl/pi_opencl.cpp

@@ -1316,6 +1316,32 @@ pi_result piKernelGetSubGroupInfo(pi_kernel kernel, pi_device device,
       cast<cl_kernel_sub_group_info>(param_name), input_value_size, input_value,
       sizeof(size_t), &ret_val, param_value_size_ret));
 
+  if (ret_err == CL_INVALID_OPERATION) {
+    // clGetKernelSubGroupInfo returns CL_INVALID_OPERATION if the device does
+    // not support subgroups.
+
+    if (param_name == PI_KERNEL_MAX_NUM_SUB_GROUPS) {
+      ret_val = 1; // Minimum required by SYCL 2020 spec
+      ret_err = CL_SUCCESS;
+    } else if (param_name == PI_KERNEL_COMPILE_NUM_SUB_GROUPS) {
+      ret_val = 0; // Not specified by kernel
+      ret_err = CL_SUCCESS;
+    } else if (param_name == PI_KERNEL_MAX_SUB_GROUP_SIZE) {
+      // Return the maximum work group size for the kernel
+      size_t kernel_work_group_size = 0;
+      pi_result pi_ret_err = piKernelGetGroupInfo(
+          kernel, device, PI_KERNEL_GROUP_INFO_WORK_GROUP_SIZE, sizeof(size_t),
+          &kernel_work_group_size, nullptr);
+      if (pi_ret_err != PI_SUCCESS)
+        return pi_ret_err;
+      ret_val = kernel_work_group_size;
+      ret_err = CL_SUCCESS;
+    } else if (param_name == PI_KERNEL_COMPILE_SUB_GROUP_SIZE_INTEL) {
+      ret_val = 0; // Not specified by kernel
+      ret_err = CL_SUCCESS;
+    }
+  }
+
   if (ret_err != CL_SUCCESS)
     return cast<pi_result>(ret_err);
 

sycl/test-e2e/Basic/kernel_info.cpp

@@ -54,6 +54,18 @@ int main() {
   const size_t prefWGSizeMult = krn.get_info<
       info::kernel_device_specific::preferred_work_group_size_multiple>(dev);
   assert(prefWGSizeMult > 0);
+  const cl_uint maxSgSize =
+      krn.get_info<info::kernel_device_specific::max_sub_group_size>(dev);
+  assert(0 < maxSgSize && maxSgSize <= wgSize);
+  const cl_uint compileSgSize =
+      krn.get_info<info::kernel_device_specific::compile_sub_group_size>(dev);
+  assert(compileSgSize <= maxSgSize);
+  const cl_uint maxNumSg =
+      krn.get_info<info::kernel_device_specific::max_num_sub_groups>(dev);
+  assert(0 < maxNumSg);
+  const cl_uint compileNumSg =
+      krn.get_info<info::kernel_device_specific::compile_num_sub_groups>(dev);
+  assert(compileNumSg <= maxNumSg);
 
   try {
     krn.get_info<sycl::info::kernel_device_specific::global_work_size>(dev);