[llvm] [libsycl] Implement fill & memset queue API (PR #217933)

[Yury Plyakhin via llvm-commits]

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@@ -0,0 +1,40 @@
+#include <sycl/sycl.hpp>
+
+#include <array>
+#include <cassert>
+
+constexpr std::size_t DataSize = 1024;
+constexpr int Pattern = 42;
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YuriPlyakhin wrote:

I think this pattern doesn't test ` static_cast<unsigned char>` of memset. for 42, fill and memset look the same.
Could you add memset test with input outside `unsigned char` range to verify truncation?

https://github.com/llvm/llvm-project/pull/217933