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

[Johannes Doerfert via llvm-commits]

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@@ -22,24 +22,95 @@
 using namespace llvm;
 using namespace llvm::omp::target::plugin;
 
-// Handle type definitions. Ideally these would be 1:1 with the plugins
-struct ol_device_handle_t_ {
+// Handle type definitions. Ideally these would be 1:1 with the plugins, but
+// we add some additional data here for now to avoid churn in the plugin
+// interface.
+struct ol_device_impl_t {
   int DeviceNum;
-  GenericDeviceTy &Device;
+  GenericDeviceTy *Device;
   ol_platform_handle_t Platform;
 };
 
-struct ol_platform_handle_t_ {
+struct ol_platform_impl_t {
   std::unique_ptr<GenericPluginTy> Plugin;
-  std::vector<ol_device_handle_t_> Devices;
+  std::vector<ol_device_impl_t> Devices;
 };
 
-using PlatformVecT = SmallVector<ol_platform_handle_t_, 4>;
+struct ol_queue_impl_t {
+  __tgt_async_info *AsyncInfo;
+  ol_device_handle_t Device;
+  std::atomic_uint32_t RefCount;
+};
+
+struct ol_event_impl_t {
+  void *EventInfo;
+  ol_queue_handle_t Queue;
+  std::atomic_uint32_t RefCount;
+};
+
+struct ol_program_impl_t {
+  llvm::omp::target::plugin::DeviceImageTy *Image;
+  std::unique_ptr<MemoryBuffer> ImageData;
+  std::atomic_uint32_t RefCount;
+};
+
+// A helper that can be used to construct the argument buffer for a kernel.
+// Alternatively, a pre-existing buffer can be set with `setArgsData`.
+struct OffloadKernelArguments {
+  static constexpr size_t MaxParamBytes = 4096u;
+  using args_t = std::array<char, MaxParamBytes>;
+  using args_size_t = std::vector<size_t>;
+  using args_ptr_t = std::vector<void *>;
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jdoerfert wrote:

I guess just search for std::vector

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