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

[Alex Duran via llvm-commits]

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@@ -0,0 +1,158 @@
+//===--- 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
+//
+//===----------------------------------------------------------------------===//
+//
+// GenericKernel implementation for SPIR-V/Xe machine
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef OPENMP_LIBOMPTARGET_PLUGINS_NEXTGEN_LEVEL_ZERO_L0KERNEL_H
+#define OPENMP_LIBOMPTARGET_PLUGINS_NEXTGEN_LEVEL_ZERO_L0KERNEL_H
+
+#include "L0Defs.h"
+#include "L0Trace.h"
+#include "PluginInterface.h"
+
+namespace llvm::omp::target::plugin {
+
+class L0DeviceTy;
+class L0ProgramTy;
+
+/// Loop descriptor
+struct TgtLoopDescTy {
+  int64_t Lb = 0;     // The lower bound of the i-th loop
+  int64_t Ub = 0;     // The upper bound of the i-th loop
+  int64_t Stride = 0; // The stride of the i-th loop
+};
+
+struct TgtNDRangeDescTy {
+  int32_t NumLoops = 0;      // Number of loops/dimensions
+  int32_t DistributeDim = 0; // Dimensions lower than this one
+                             // must end up in one WG
+  TgtLoopDescTy Levels[3];   // Up to 3 loops
+};
+
+/// Kernel properties.
+struct KernelPropertiesTy {
+  uint32_t Width = 0;
+  uint32_t SIMDWidth = 0;
+  uint32_t MaxThreadGroupSize = 0;
+
+  /// Cached input parameters used in the previous launch
+  TgtNDRangeDescTy LoopDesc;
+  int32_t NumTeams = -1;
+  int32_t ThreadLimit = -1;
+
+  /// Cached parameters used in the previous launch
+  ze_kernel_indirect_access_flags_t IndirectAccessFlags = UINT32_MAX;
+  uint32_t GroupSizes[3] = {0, 0, 0};
+  ze_group_count_t GroupCounts{0, 0, 0};
+  bool AllowCooperative = false;
+
+  std::mutex Mtx;
+
+  static constexpr TgtNDRangeDescTy LoopDescInit = {};
+
+  /// Check if we can reuse group parameters.
+  bool reuseGroupParams(const TgtNDRangeDescTy *LoopDescPtr,
+                        const int32_t NumTeamsIn, const int32_t ThreadLimitIn,
+                        uint32_t *GroupSizesOut,
+                        ze_group_count_t &GroupCountsOut,
+                        bool &AllowCooperativeOut) const {
+    if (!LoopDescPtr && memcmp(&LoopDescInit, &LoopDesc, sizeof(LoopDesc)))
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adurang wrote:

Yes. I added the operators to allow "!=".

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