[llvm] [libsycl] Initial prefetch implementation for queue (PR #212104)

[Kseniya Tikhomirova via llvm-commits]

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@@ -345,7 +345,19 @@ void mock::MockLiboffload::initDefault() {
           return makeEmptyStrError(OL_ERRC_INVALID_NULL_POINTER);
         return OL_SUCCESS;
       });
-
+  ON_CALL(*this, olMemPrefetch)
+      .WillByDefault([this](ol_queue_handle_t Queue, size_t Count,
+                            const void **Mems, const size_t *Sizes,
+                            ol_mem_migration_flags_t Flags) -> ol_result_t {
+        if (!Queue)
+          return makeEmptyStrError(OL_ERRC_INVALID_NULL_HANDLE);
+        if (Count > 0 && (Mems == nullptr || Sizes == nullptr))
+          return makeEmptyStrError(OL_ERRC_INVALID_NULL_POINTER);
+        if ((Flags & ~(OL_MEM_MIGRATION_FLAG_HOST_TO_DEVICE |
+                       OL_MEM_MIGRATION_FLAG_DEVICE_TO_HOST)) != 0)
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KseniyaTikhomirova wrote:

please rebase and change the impl to the new approach

https://github.com/llvm/llvm-project/pull/212104