[SYCL] Fix Kernel Compiler OpenCLC_Supports_Extension (#14959)

The optional parameter `VersionPtr` is `nullptr` by default. But, the
code assumes it is a valid pointer.
So, the fix is to guard with an `if` conditional phrase.

Author: bso-intel

sycl/source/detail/kernel_compiler/kernel_compiler_opencl.cpp

@@ -340,6 +340,12 @@ bool OpenCLC_Supports_Extension(
         "trouble parsing query returned from CL_DEVICE_EXTENSIONS_WITH_VERSION "
         "- extension not followed by colon (:)");
   }
+
+  // Note that VersionPtr is an optional parameter in
+  // ext_oneapi_supports_cl_extension().
+  if (!VersionPtr)
+    return true;
+
   colon++; // move it forward
 
   size_t space = ExtensionByVersionLog.find(' ', colon); // could be npos
@@ -360,7 +366,6 @@ bool OpenCLC_Supports_Extension(
   VersionPtr->major = std::stoi(versionVec[0]);
   VersionPtr->minor = std::stoi(versionVec[1]);
   VersionPtr->patch = std::stoi(versionVec[2]);
-
   return true;
 }
 

sycl/test-e2e/KernelCompiler/opencl_queries.cpp

@@ -41,6 +41,26 @@ int main() {
            "version not updated");
   }
 
+  // test without version pointer
+  bool has_bf16_conversion =
+      d.ext_oneapi_supports_cl_extension("cl_intel_bf16_conversion");
+  std::cout << "has_bf16_conversion: " << has_bf16_conversion << std::endl;
+  bool has_subgroup_matrix_multiply_accumulate =
+      d.ext_oneapi_supports_cl_extension(
+          "cl_intel_subgroup_matrix_multiply_accumulate");
+  std::cout << "has_subgroup_matrix_multiply_accumulate: "
+            << has_subgroup_matrix_multiply_accumulate << std::endl;
+  bool has_subgroup_matrix_multiply_accumulate_tensor_float32 =
+      d.ext_oneapi_supports_cl_extension(
+          "cl_intel_subgroup_matrix_multiply_accumulate_tensor_float32");
+  std::cout << "has_subgroup_matrix_multiply_accumulate_tensor_float32: "
+            << has_subgroup_matrix_multiply_accumulate_tensor_float32
+            << std::endl;
+  bool has_subgroup_2d_block_io =
+      d.ext_oneapi_supports_cl_extension("cl_intel_subgroup_2d_block_io");
+  std::cout << "has_subgroup_2d_block_io: " << has_subgroup_2d_block_io
+            << std::endl;
+
   // no supported devices support EMBEDDED_PROFILE at this time.
   assert(d.ext_oneapi_cl_profile() == "FULL_PROFILE" &&
          "unexpected cl_profile");