[SYCL] Move fp64_relaxed E2E test (#8829)

This commit moves the in-review fp64_relaxed.cpp test from the now
archived intel/llvm-test-suite repo.

See intel/llvm-test-suite#1668.

Signed-off-by: Larsen, Steffen <[email protected]>

Author: steffenlarsen

sycl/test-e2e/OptionalKernelFeatures/fp64_relaxed.cpp

@@ -0,0 +1,41 @@
+// RUN: %clangxx -fsycl -fsycl-targets=%sycl_triple -DOPTIMIZATIONS_DISABLED=0 %s -o %t_opt.out
+// RUN: %CPU_RUN_PLACEHOLDER %t_opt.out
+// RUN: %GPU_RUN_PLACEHOLDER %t_opt.out
+// RUN: %ACC_RUN_PLACEHOLDER %t_opt.out
+// RUN: %clangxx -fsycl -fsycl-targets=%sycl_triple -fno-sycl-early-optimizations -DOPTIMIZATIONS_DISABLED=1 %s -o %t_noopt.out
+// RUN: %CPU_RUN_PLACEHOLDER %t_noopt.out
+// RUN: %GPU_RUN_PLACEHOLDER %t_noopt.out
+// RUN: %ACC_RUN_PLACEHOLDER %t_noopt.out
+
+// Tests that aspect::fp64 requirements are affected by optimizations.
+
+#include <sycl/sycl.hpp>
+
+int main() {
+  sycl::queue Q;
+  try {
+    Q.single_task([=]() {
+      // Double will be optimized out as LoweredFloat can be set directly to a
+      // lowered value.
+      double Double = 3.14;
+      volatile float LoweredFloat = Double;
+    });
+#if (OPTIMIZATIONS_DISABLED == 1)
+    assert(Q.get_device().has(sycl::aspect::fp64) &&
+           "Exception should have been thrown.");
+#endif // OPTIMIZATIONS_DISABLED
+  } catch (sycl::exception &E) {
+    std::cout << "Caught exception: " << E.what() << std::endl;
+    assert(OPTIMIZATIONS_DISABLED &&
+           "Optimizations should have removed the fp64 requirement.");
+    assert(!Q.get_device().has(sycl::aspect::fp64) &&
+           "Exception thrown despite fp64 support.");
+    assert(E.code() == sycl::errc::kernel_not_supported &&
+           "Exception did not have the expected error code.");
+  } catch (...) {
+    std::cout << "Unexpected exception thrown!" << std::endl;
+    throw;
+  }
+
+  return 0;
+}