[SYCL] Use host device explicitly and add default ctor tests

SYCL/Basic/default_device.cpp

@@ -0,0 +1,21 @@
+//==--------- default_device.cpp - SYCL device default ctor test -----------==//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// RUN: %clangxx -fsycl -fsycl-targets=%sycl_triple %s -o %t.out
+// RUN: %HOST_RUN_PLACEHOLDER %t.out
+// RUN: %CPU_RUN_PLACEHOLDER %t.out
+// RUN: %GPU_RUN_PLACEHOLDER %t.out
+// RUN: %ACC_RUN_PLACEHOLDER %t.out
+
+#include <sycl/sycl.hpp>
+
+int main() {
+  sycl::device Dev;
+  assert(Dev == sycl::device{sycl::default_selector_v});
+  return 0;
+}

SYCL/Basic/default_platform.cpp

@@ -0,0 +1,21 @@
+//==------- default_platform.cpp - SYCL platform default ctor test ---------==//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// RUN: %clangxx -fsycl -fsycl-targets=%sycl_triple %s -o %t.out
+// RUN: %HOST_RUN_PLACEHOLDER %t.out
+// RUN: %CPU_RUN_PLACEHOLDER %t.out
+// RUN: %GPU_RUN_PLACEHOLDER %t.out
+// RUN: %ACC_RUN_PLACEHOLDER %t.out
+
+#include <sycl/sycl.hpp>
+
+int main() {
+  sycl::platform Plt;
+  assert(Plt == sycl::platform{sycl::default_selector_v});
+  return 0;
+}

SYCL/Basic/device_equality.cpp

@@ -37,8 +37,8 @@ int main() {
   assert((dev1 == dev2) && "Device 1 == Device 2");
   assert((plat1 == plat2) && "Platform 1 == Platform 2");
 
-  device h1;
-  device h2;
+  device h1{host_selector{}};
+  device h2{host_selector{}};
 
   assert(h1.is_host() && "Device h1 is host");
   assert(h2.is_host() && "Device h2 is host");

SYCL/FilterSelector/select.cpp

@@ -23,7 +23,6 @@ int main() {
   std::vector<device> GPUs;
   std::vector<device> Accels;
   std::vector<device> Devs;
-  device host;
 
   CPUs = device::get_devices(info::device_type::cpu);
   GPUs = device::get_devices(info::device_type::gpu);

SYCL/USM/pointer_query.cpp

@@ -29,7 +29,6 @@ int main() {
     return 0;
 
   usm::alloc Kind;
-  device D;
 
   // Test device allocs
   array = (int *)malloc_device(N * sizeof(int), q);
@@ -48,7 +47,7 @@ int main() {
       return 3;
     }
   }
-  D = get_pointer_device(array, ctxt);
+  device D = get_pointer_device(array, ctxt);
   if (D != dev) {
     return 4;
   }