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

[Sergey Semenov via llvm-commits]

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@@ -194,6 +194,27 @@ QueueImpl::memcpy(void *Dest, const void *Src, std::size_t NumBytes,
   return createEvent();
 }
 
+EventImplPtr QueueImpl::fill(void *Ptr, const void *Pattern,
+                             std::size_t PatternSize, std::size_t Count,
+                             const std::vector<EventImplPtr> &DepEvents) {
+  assert(PatternSize > 0);
+  checkEventsPlatformMatch(DepEvents, MDevice.getPlatformImpl());
+  if (Count == 0) {
+    handleEventDependencies(DepEvents);
+    return createEvent();
+  }
+
+  if (!Ptr) {
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sergey-semenov wrote:

I disagree, I think nullptr is a valid pointer to copy 0 bytes to by virtue of it being a no-op.

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