[SYCL] Sort platforms in platform::get_platforms() (#12719)

So that the first one would contain the most preferrable device in case
SYCL applications/library performs manual device selection and defaults
to the first available device.

sycl/source/detail/platform_impl.cpp

@@ -203,6 +203,31 @@ std::vector<platform> platform_impl::get_platforms() {
  // may be initialized after.
  GlobalHandler::registerDefaultContextReleaseHandler();
 
+ // Some applications/libraries prefer to implement their own device selection
+ // and default to just providing the first available device. Make sure that
+ // the first platform has the most preferrable device.
+ auto GetPlatformScore = [](const platform &p) {
+ auto devs = p.get_devices();
+ auto it =
+ std::max_element(devs.begin(), devs.end(), [](auto lhs, auto rhs) {
+ return default_selector_v(lhs) < default_selector_v(rhs);
+ });
+ return default_selector_v(*it);
+ };
+
+ std::vector<std::pair<platform, int>> PlatformScores;
+ PlatformScores.reserve(Platforms.size());
+ for (auto &p : Platforms)
+ PlatformScores.emplace_back(p, GetPlatformScore(p));
+
+ std::stable_sort(PlatformScores.begin(), PlatformScores.end(), [&](auto lhs, auto rhs) {
+ return lhs.second > rhs.second;
+ });
+
+ Platforms.clear();
+ for (auto &e : PlatformScores )
+ Platforms.push_back(e.first);
+
  return Platforms;
 }
 

sycl/test-e2e/Basic/get_backend.cpp

@@ -1,8 +1,7 @@
-// Sporadic fails on DG2
-// TODO: Reenable when internal ticket is resolved
-// UNSUPPORTED: gpu-intel-dg2
 // RUN: %{build} -o %t.out
-// RUN: %{run-unfiltered-devices} %t.out
+// FPGA RT returns random CL_INVALID_CONTEXT in some configurations, tracked
+// internally. Avoid FPGA devices until that is fixed.
+// RUN: env ONEAPI_DEVICE_SELECTOR="*:gpu;*:cpu" %{run-unfiltered-devices} %t.out
 //
 //==----------------- get_backend.cpp ------------------------==//
 // This is a test of get_backend().

sycl/test-e2e/Config/select_device.cpp

@@ -123,7 +123,11 @@ static std::vector<DevDescT> getAllowListDesc(std::string allowList) {
  throw std::runtime_error("Malformed device allowlist");
  }
  decDescs.back().devDriverVer = allowList.substr(start, pos - start);
- pos = pos + 3;
+ pos = pos + 2;
+
+ if (allowList[pos] == ',') {
+ pos++;
+ }
  }
 
  else if ((allowList.compare(pos, platformName.size(), platformName)) == 0) {