[llvm] [Offload] Implement the remaining initial Offload API (PR #122106)

[Callum Fare via llvm-commits]

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@@ -245,3 +308,300 @@ ol_impl_result_t olGetDeviceInfoSize_impl(ol_device_handle_t Device,
                                           size_t *PropSizeRet) {
   return olGetDeviceInfoImplDetail(Device, PropName, 0, nullptr, PropSizeRet);
 }
+
+TargetAllocTy convertOlToPluginAllocTy(ol_alloc_type_t Type) {
+  switch (Type) {
+  case OL_ALLOC_TYPE_DEVICE:
+    return TARGET_ALLOC_DEVICE;
+  case OL_ALLOC_TYPE_HOST:
+    return TARGET_ALLOC_HOST;
+  case OL_ALLOC_TYPE_SHARED:
+  default:
+    return TARGET_ALLOC_SHARED;
+  }
+}
+
+ol_impl_result_t olMemAlloc_impl(ol_device_handle_t Device,
+                                 ol_alloc_type_t Type, size_t Size,
+                                 void **AllocationOut) {
+  auto Alloc =
+      Device->Device.dataAlloc(Size, nullptr, convertOlToPluginAllocTy(Type));
+  if (!Alloc) {
+    return {OL_ERRC_OUT_OF_RESOURCES,
+            formatv("Could not create allocation on device {0}", Device).str()};
+  }
+
+  *AllocationOut = *Alloc;
+  return OL_SUCCESS;
+}
+
+ol_impl_result_t olMemFree_impl(ol_device_handle_t Device, ol_alloc_type_t Type,
+                                void *Address) {
+  auto Res = Device->Device.dataDelete(Address, convertOlToPluginAllocTy(Type));
+  if (Res) {
+    return {OL_ERRC_OUT_OF_RESOURCES, "Could not free allocation"};
+  }
+  return OL_SUCCESS;
+}
+
+ol_impl_result_t olCreateQueue_impl(ol_device_handle_t Device,
+                                    ol_queue_handle_t *Queue) {
+  auto CreatedQueue = std::make_unique<ol_queue_handle_t_>();
+  auto Err = Device->Device.initAsyncInfo(&(CreatedQueue->AsyncInfo));
+  if (Err) {
+    return OL_ERRC_OUT_OF_RESOURCES;
+  }
+  // TODO: Check error
+  CreatedQueue->Device = Device;
+  CreatedQueue->RefCount = 1;
+  *Queue = CreatedQueue.release();
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callumfare wrote:

It's useful when you need the allocation to happen before multiple possible early exits in the functions - means you don't need to remember to free the allocation each time. But I can change this if you'd rather it happens explicitly.

https://github.com/llvm/llvm-project/pull/122106