[llvm] [libsycl] Add device image registration & compatibility check (PR #187528)

[Alexey Bader via llvm-commits]

================
@@ -0,0 +1,95 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBSYCL_PROGRAM_MANAGER
+#define _LIBSYCL_PROGRAM_MANAGER
+
+#include <sycl/__impl/detail/config.hpp>
+
+#include <detail/device_binary_structures.hpp>
+#include <detail/device_image_wrapper.hpp>
+#include <detail/kernel_id.hpp>
+
+#include <mutex>
+#include <unordered_map>
+
+// +++ Entry points referenced by the offload wrapper object {
+
+/// Executed as a part of current module's (.exe, .dll) static initialization.
+/// Registers device executable images with the runtime.
+extern "C" _LIBSYCL_EXPORT void __sycl_register_lib(__sycl_tgt_bin_desc *desc);
+
+/// Executed as a part of current module's (.exe, .dll) static
+/// de-initialization.
+/// Unregisters device executable images with the runtime.
+extern "C" _LIBSYCL_EXPORT void
+__sycl_unregister_lib(__sycl_tgt_bin_desc *desc);
+
+// +++ }
+
+_LIBSYCL_BEGIN_NAMESPACE_SYCL
+
+namespace detail {
+
+class DeviceImpl;
+
+/// A class to manage programs and kernels.
+class ProgramManager {
+
+public:
+  static ProgramManager &getInstance() {
+    static ProgramManager PM{};
+    return PM;
+  }
+
+  /// Parses raw device images data and prepare internal structures for
+  /// effective kernel/program creation.
+  /// \param FatbinDesc a record of all the device code that may be offloaded
+  /// generated by compiler and offloading tools.
+  /// \throw sycl::exception with sycl::errc::runtime if device image descriptor
+  /// has incompatible version or if device image has incompatible
+  /// version/target/kind.
+  void addImages(__sycl_tgt_bin_desc *FatbinDesc);
+
+  /// Removes all entries of the data in FatbinDesc in internal structures.
+  /// \param FatbinDesc a record of all the device code that may be offloaded
+  /// generated by compiler and offloading tools. Must match the pointer and
+  /// data passed to addImages.
+  void removeImages(__sycl_tgt_bin_desc *FatbinDesc);
+
+private:
+  ProgramManager() = default;
+  ~ProgramManager() = default;
+  ProgramManager(ProgramManager const &) = delete;
+  ProgramManager &operator=(ProgramManager const &) = delete;
+
+  /// Searches for device image that contains requested kernel and is compatible
+  /// with requested device.
+  /// \param KernelName a null-terminated string representing the name of kernel
+  /// to obtain device image for.
+  /// \param KernelID a kernel id matching KernelName.
+  /// \param DeviceImpl a device that device image must be compatible with.
+  /// \throw sycl::exception with sycl::errc::runtime if device image validness
+  /// check failed in liboffload or if no compatible image was found.
+  DeviceImageWrapper *getDeviceImage(const char *KernelName, kernel_id KernelID,
+                                     DeviceImpl &Device);
+
+  // Filled by addImages(...).
----------------
bader wrote:

I agree that both versions are acceptable, but we can improve the name to describe what the function does more precisely than `addImages`. IMHO `addImages` is too vague.

https://github.com/llvm/llvm-project/pull/187528