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

[Alexey Sachkov via llvm-commits]

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@@ -0,0 +1,1065 @@
+//===--- 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
+//
+//===----------------------------------------------------------------------===//
+//
+// GenericDevice instatiation for SPIR-V/Xe machine
+//
+//===----------------------------------------------------------------------===//
+
+#include "L0Device.h"
+#include "L0Defs.h"
+#include "L0Interop.h"
+#include "L0Plugin.h"
+#include "L0Program.h"
+#include "L0Trace.h"
+
+namespace llvm::omp::target::plugin {
+
+L0DeviceTLSTy &L0DeviceTy::getTLS() {
+  return getPlugin().getDeviceTLS(getDeviceId());
+}
+
+// clang-format off
+/// Mapping from device arch to GPU runtime's device identifiers
+static struct {
+  DeviceArchTy arch;
+  PCIIdTy ids[10];
+} DeviceArchMap[] = {{DeviceArchTy::DeviceArch_Gen,
+                      {PCIIdTy::SKL,
+                       PCIIdTy::KBL,
+                       PCIIdTy::CFL, PCIIdTy::CFL_2,
+                       PCIIdTy::ICX,
+                       PCIIdTy::None}},
+                     {DeviceArchTy::DeviceArch_Gen,
+                      {PCIIdTy::TGL, PCIIdTy::TGL_2,
+                       PCIIdTy::DG1,
+                       PCIIdTy::RKL,
+                       PCIIdTy::ADLS,
+                       PCIIdTy::RTL,
+                       PCIIdTy::None}},
+                     {DeviceArchTy::DeviceArch_XeLPG,
+                      {PCIIdTy::MTL,
+                       PCIIdTy::None}},
+                     {DeviceArchTy::DeviceArch_XeHPC,
+                      {PCIIdTy::PVC,
+                       PCIIdTy::None}},
+                     {DeviceArchTy::DeviceArch_XeHPG,
+                      {PCIIdTy::DG2_ATS_M,
+                       PCIIdTy::DG2_ATS_M_2,
+                       PCIIdTy::None}},
+                     {DeviceArchTy::DeviceArch_Xe2LP,
+                      {PCIIdTy::LNL,
+                       PCIIdTy::None}},
+                     {DeviceArchTy::DeviceArch_Xe2HP,
+                      {PCIIdTy::BMG,
+                       PCIIdTy::None}},
+};
+constexpr int DeviceArchMapSize = sizeof(DeviceArchMap) / sizeof(DeviceArchMap[0]);
+// clang-format on
+
+DeviceArchTy L0DeviceTy::computeArch() const {
+  const auto PCIDeviceId = getPCIId();
+  if (PCIDeviceId != 0) {
+    for (int arch = 0; arch < DeviceArchMapSize; arch++) {
+      for (int i = 0;; i++) {
+        const auto Id = DeviceArchMap[arch].ids[i];
+        if (Id == PCIIdTy::None)
+          break;
+
+        auto maskedId = static_cast<PCIIdTy>(PCIDeviceId & 0xFF00);
+        if (maskedId == Id)
+          return DeviceArchMap[arch].arch; // Exact match or prefix match
----------------
AlexeySachkov wrote:

```suggestion
          return DeviceArchMap[ArchIndex].arch; // Exact match or prefix match
```

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