[llvm] [OFFLOAD] Add plugin with support for Intel oneAPI Level Zero (PR #158900)

[Alex Duran via llvm-commits]

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@@ -0,0 +1,161 @@
+//===--- Level Zero Target RTL Implementation -----------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+//
+// Level Zero RTL Options support
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef OPENMP_LIBOMPTARGET_PLUGINS_NEXTGEN_LEVEL_ZERO_L0OPTIONS_H
+#define OPENMP_LIBOMPTARGET_PLUGINS_NEXTGEN_LEVEL_ZERO_L0OPTIONS_H
+
+#include <level_zero/ze_api.h>
+
+#include "Shared/EnvironmentVar.h"
+
+#include "L0Defs.h"
+
+namespace llvm::omp::target::plugin {
+/// Command submission mode
+enum class CommandModeTy { Sync = 0, Async, AsyncOrdered };
+
+/// Specialization constants used for a module compilation.
+class SpecConstantsTy {
+  std::vector<uint32_t> ConstantIds;
+  std::vector<const void *> ConstantValues;
+  BumpPtrAllocator &Allocator;
+
+public:
+  SpecConstantsTy(BumpPtrAllocator &Allocator) : Allocator(Allocator) {}
+  SpecConstantsTy(const SpecConstantsTy &) = delete;
+  SpecConstantsTy(SpecConstantsTy &&) = delete;
+  SpecConstantsTy &operator=(const SpecConstantsTy &) = delete;
+  SpecConstantsTy &operator=(const SpecConstantsTy &&) = delete;
+  SpecConstantsTy(const SpecConstantsTy &&Other)
+      : ConstantIds(std::move(Other.ConstantIds)),
+        ConstantValues(std::move(Other.ConstantValues)),
+        Allocator(Other.Allocator) {}
+  ~SpecConstantsTy() {}
+
+  template <typename T> void addConstant(uint32_t Id, T Val) {
+    T *ValuePtr =
+        reinterpret_cast<T *>(Allocator.Allocate(sizeof(T), alignof(T)));
+    *ValuePtr = Val;
+
+    ConstantIds.push_back(Id);
+    ConstantValues.push_back(reinterpret_cast<void *>(ValuePtr));
+  }
+
+  ze_module_constants_t getModuleConstants() const {
+    ze_module_constants_t Tmp{static_cast<uint32_t>(ConstantValues.size()),
+                              ConstantIds.data(),
+                              // Unfortunately we have to const_cast it.
+                              // L0 data type should probably be fixed.
+                              const_cast<const void **>(ConstantValues.data())};
+    return Tmp;
+  }
+};
+
+/// L0 Plugin flags
+struct L0OptionFlagsTy {
+  uint64_t UseMemoryPool : 1;
+  uint64_t Reserved : 63;
+  L0OptionFlagsTy() : UseMemoryPool(1), Reserved(0) {}
+};
+
+struct L0OptionsTy {
+  /// Binary flags
+  L0OptionFlagsTy Flags;
+
+  /// Staging buffer size
+  size_t StagingBufferSize = L0StagingBufferSize;
+
+  /// Staging buffer count
+  size_t StagingBufferCount = L0StagingBufferCount;
+
+  // TODO: This should probably be an array indexed by AllocKind
+  /// Memory pool parameters
+  /// MemPoolInfo[MemType] = {AllocMax(MB), Capacity, PoolSize(MB)}
+  std::map<int32_t, std::array<int32_t, 3>> MemPoolInfo = {
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adurang wrote:

Not really but it's not easy to replace because how it's used in some places. This is in my todo list to clean-up but would prefer to do that later.

https://github.com/llvm/llvm-project/pull/158900