[SYCL][NFC] Check alignment for key SYCL types (#2788)

Alignment of the type is part of ABI. Changing type aligment is a
breaking change. Cover this with tests.

Author: Alexander Batashev

sycl/test/abi/symbol_size.cpp

@@ -1,7 +1,7 @@
 // RUN: %clangxx -fsycl %s -o %t
 
-// Changing symbol size is a breaking change. If it happens, refer to the ABI
-// Policy Guide for further instructions on breaking ABI.
+// Changing symbol size or alignment is a breaking change. If it happens, refer
+// to the ABI Policy Guide for further instructions on breaking ABI.
 
 #include <CL/sycl/accessor.hpp>
 #include <CL/sycl/buffer.hpp>
@@ -21,58 +21,71 @@
 #include <CL/sycl/queue.hpp>
 #include <CL/sycl/sampler.hpp>
 #include <CL/sycl/stream.hpp>
+#include <CL/sycl/types.hpp>
 
 using namespace cl::sycl;
 
-template <int newSize, int oldSize>
-void check_size() {
+template <int newSize, int oldSize> void check_size() {
   static_assert(newSize == oldSize, "Symbol size has changed.");
 }
 
-template <typename T, size_t oldSize>
-void check_size() {
+template <int newAlignment, int oldAlignment> void check_alignment() {
+  static_assert(newAlignment == oldAlignment, "Alignment has changed");
+}
+
+template <typename T, size_t oldSize, size_t oldAlignment> void check() {
   check_size<sizeof(T), oldSize>();
+  check_alignment<alignof(T), oldAlignment>();
 }
 
 int main() {
   using accessor_t = accessor<int, 1, access::mode::read,
                               access::target::global_buffer,
                               access::placeholder::true_t>;
-  check_size<accessor_t, 32>();
-  check_size<detail::AccessorImplDevice<1>, 24>();
-  check_size<detail::LocalAccessorBaseDevice<1>, 24>();
-  check_size<detail::AccessorImplHost, 128>();
-  check_size<detail::AccessorBaseHost, 16>();
-  check_size<detail::LocalAccessorImplHost, 56>();
-  check_size<buffer<int>, 40>();
-  check_size<context, 16>();
-  check_size<cpu_selector, 8>();
-  check_size<device, 16>();
-  check_size<device_event, 8>();
-  check_size<device_selector, 8>();
-  check_size<event, 16>();
-  check_size<gpu_selector, 8>();
+  check<accessor_t, 32, 8>();
+  check<detail::AccessorImplDevice<1>, 24, 8>();
+  check<detail::LocalAccessorBaseDevice<1>, 24, 8>();
+  check<detail::AccessorImplHost, 128, 8>();
+  check<detail::AccessorBaseHost, 16, 8>();
+  check<detail::LocalAccessorImplHost, 56, 8>();
+  check<buffer<int>, 40, 8>();
+  check<context, 16, 8>();
+  check<cpu_selector, 8, 8>();
+  check<device, 16, 8>();
+  check<device_event, 8, 8>();
+  check<device_selector, 8, 8>();
+  check<event, 16, 8>();
+  check<gpu_selector, 8, 8>();
 #ifdef _MSC_VER
-  check_size<handler, 552>();
-  check_size<detail::buffer_impl, 216>();
-  check_size<detail::image_impl<1>, 272>();
+  check<handler, 552, 8>();
+  check<detail::buffer_impl, 216, 8>();
+  check<detail::image_impl<1>, 272, 8>();
 #else
-  check_size<handler, 560>();
-  check_size<detail::buffer_impl, 184>();
-  check_size<detail::image_impl<1>, 240>();
+  check<handler, 560, 8>();
+  check<detail::buffer_impl, 184, 8>();
+  check<detail::image_impl<1>, 240, 8>();
 #endif
-  check_size<image<1>, 16>();
-  check_size<kernel, 16>();
-  check_size<platform, 16>();
+  check<image<1>, 16, 8>();
+  check<kernel, 16, 8>();
+  check<platform, 16, 8>();
 #ifdef __SYCL_DEVICE_ONLY__
-  check_size<private_memory<int, 1>, 4>();
-  check_size<detail::sampler_impl, 8>();
+  check<private_memory<int, 1>, 4, 4>();
+  check<detail::sampler_impl, 8, 8>();
 #endif
-  check_size<program, 16>();
-  check_size<range<1>, 8>();
-  check_size<sampler, 16>();
-  check_size<stream, 144>();
-  check_size<queue, 16>();
+  check<program, 16, 8>();
+  check<range<1>, 8, 8>();
+  check<sampler, 16, 8>();
+  check<stream, 144, 8>();
+  check<queue, 16, 8>();
+  check<vec<float, 1>, 4, 4>();
+  check<vec<float, 2>, 8, 8>();
+  check<vec<float, 4>, 16, 16>();
+  check<vec<float, 8>, 32, 32>();
+  check<vec<float, 16>, 64, 64>();
+  check<vec<double, 1>, 8, 8>();
+  check<vec<double, 2>, 16, 16>();
+  check<vec<double, 4>, 32, 32>();
+  check<vec<double, 8>, 64, 64>();
 
   return 0;
 }