Reland #118503: [Offload] Introduce offload-tblgen and initial new API implementation (#118614)

Reland #118503. Added a fix for builds with `-DBUILD_SHARED_LIBS=ON`
(see last commit). Otherwise the changes are identical.

---


### New API

Previous discussions at the LLVM/Offload meeting have brought up the
need for a new API for exposing the functionality of the plugins. This
change introduces a very small subset of a new API, which is primarily
for testing the offload tooling and demonstrating how a new API can fit
into the existing code base without being too disruptive. Exact designs
for these entry points and future additions can be worked out over time.

The new API does however introduce the bare minimum functionality to
implement device discovery for Unified Runtime and SYCL. This means that
the `urinfo` and `sycl-ls` tools can be used on top of Offload. A
(rough) implementation of a Unified Runtime adapter (aka plugin) for
Offload is available
[here](https://github.com/callumfare/unified-runtime/tree/offload_adapter).
Our intention is to maintain this and use it to implement and test
Offload API changes with SYCL.

### Demoing the new API

```sh
# From the runtime build directory
$ ninja LibomptUnitTests
$ OFFLOAD_TRACE=1 ./offload/unittests/OffloadAPI/offload.unittests 
```


### Open questions and future work
* Only some of the available device info is exposed, and not all the
possible device queries needed for SYCL are implemented by the plugins.
A sensible next step would be to refactor and extend the existing device
info queries in the plugins. The existing info queries are all strings,
but the new API introduces the ability to return any arbitrary type.
* It may be sensible at some point for the plugins to implement the new
API directly, and the higher level code on top of it could be made
generic, but this is more of a long-term possibility.

5 files changed, 222 insertions, 0 deletions

diff --git a/offload/unittests/OffloadAPI/device/olDeviceInfo.hpp b/offload/unittests/OffloadAPI/device/olDeviceInfo.hpp
new file mode 100644
index 0000000..0691525
--- /dev/null
+++ b/offload/unittests/OffloadAPI/device/olDeviceInfo.hpp
@@ -0,0 +1,21 @@
+//===------- Offload API tests - Helpers for device info query testing ----===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+#pragma once
+
+#include <unordered_map>
+#include <vector>
+
+// TODO: We could autogenerate these
+inline std::vector<ol_device_info_t> DeviceQueries = {
+    OL_DEVICE_INFO_TYPE, OL_DEVICE_INFO_PLATFORM, OL_DEVICE_INFO_NAME,
+    OL_DEVICE_INFO_VENDOR, OL_DEVICE_INFO_DRIVER_VERSION};
+
+inline std::unordered_map<ol_device_info_t, size_t> DeviceInfoSizeMap = {
+    {OL_DEVICE_INFO_TYPE, sizeof(ol_device_type_t)},
+    {OL_DEVICE_INFO_PLATFORM, sizeof(ol_platform_handle_t)},
+};
diff --git a/offload/unittests/OffloadAPI/device/olGetDevice.cpp b/offload/unittests/OffloadAPI/device/olGetDevice.cpp
new file mode 100644
index 0000000..68d4682d
--- /dev/null
+++ b/offload/unittests/OffloadAPI/device/olGetDevice.cpp
@@ -0,0 +1,39 @@
+//===------- Offload API tests - olGetDevice -------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#include "../common/Fixtures.hpp"
+#include <OffloadAPI.h>
+#include <gtest/gtest.h>
+
+using olGetDeviceTest = offloadPlatformTest;
+
+TEST_F(olGetDeviceTest, Success) {
+  uint32_t Count = 0;
+  ASSERT_SUCCESS(olGetDeviceCount(Platform, &Count));
+  if (Count == 0)
+    GTEST_SKIP() << "No available devices on this platform.";
+
+  std::vector<ol_device_handle_t> Devices(Count);
+  ASSERT_SUCCESS(olGetDevice(Platform, Count, Devices.data()));
+  for (auto Device : Devices) {
+    ASSERT_NE(nullptr, Device);
+  }
+}
+
+TEST_F(olGetDeviceTest, SuccessSubsetOfDevices) {
+  uint32_t Count;
+  ASSERT_SUCCESS(olGetDeviceCount(Platform, &Count));
+  if (Count < 2)
+    GTEST_SKIP() << "Only one device is available on this platform.";
+
+  std::vector<ol_device_handle_t> Devices(Count - 1);
+  ASSERT_SUCCESS(olGetDevice(Platform, Count - 1, Devices.data()));
+  for (auto Device : Devices) {
+    ASSERT_NE(nullptr, Device);
+  }
+}
diff --git a/offload/unittests/OffloadAPI/device/olGetDeviceCount.cpp b/offload/unittests/OffloadAPI/device/olGetDeviceCount.cpp
new file mode 100644
index 0000000..ef377d6
--- /dev/null
+++ b/offload/unittests/OffloadAPI/device/olGetDeviceCount.cpp
@@ -0,0 +1,28 @@
+//===------- Offload API tests - olGetDeviceCount --------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#include "../common/Fixtures.hpp"
+#include <OffloadAPI.h>
+#include <gtest/gtest.h>
+
+using olGetDeviceCountTest = offloadPlatformTest;
+
+TEST_F(olGetDeviceCountTest, Success) {
+  uint32_t Count = 0;
+  ASSERT_SUCCESS(olGetDeviceCount(Platform, &Count));
+}
+
+TEST_F(olGetDeviceCountTest, InvalidNullPlatform) {
+  uint32_t Count = 0;
+  ASSERT_ERROR(OL_ERRC_INVALID_NULL_HANDLE, olGetDeviceCount(nullptr, &Count));
+}
+
+TEST_F(olGetDeviceCountTest, InvalidNullPointer) {
+  ASSERT_ERROR(OL_ERRC_INVALID_NULL_POINTER,
+               olGetDeviceCount(Platform, nullptr));
+}
diff --git a/offload/unittests/OffloadAPI/device/olGetDeviceInfo.cpp b/offload/unittests/OffloadAPI/device/olGetDeviceInfo.cpp
new file mode 100644
index 0000000..c936802
--- /dev/null
+++ b/offload/unittests/OffloadAPI/device/olGetDeviceInfo.cpp
@@ -0,0 +1,76 @@
+//===------- Offload API tests - olGetDeviceInfo ---------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#include "../common/Fixtures.hpp"
+#include "olDeviceInfo.hpp"
+#include <OffloadAPI.h>
+#include <gtest/gtest.h>
+
+struct olGetDeviceInfoTest : offloadDeviceTest,
+                             ::testing::WithParamInterface<ol_device_info_t> {
+
+  void SetUp() override { RETURN_ON_FATAL_FAILURE(offloadDeviceTest::SetUp()); }
+};
+
+INSTANTIATE_TEST_SUITE_P(
+    , olGetDeviceInfoTest, ::testing::ValuesIn(DeviceQueries),
+    [](const ::testing::TestParamInfo<ol_device_info_t> &info) {
+      std::stringstream ss;
+      ss << info.param;
+      return ss.str();
+    });
+
+TEST_P(olGetDeviceInfoTest, Success) {
+  ol_device_info_t InfoType = GetParam();
+  size_t Size = 0;
+
+  ASSERT_SUCCESS(olGetDeviceInfoSize(Device, InfoType, &Size));
+
+  std::vector<char> InfoData(Size);
+  ASSERT_SUCCESS(olGetDeviceInfo(Device, InfoType, Size, InfoData.data()));
+
+  if (InfoType == OL_DEVICE_INFO_PLATFORM) {
+    auto *ReturnedPlatform =
+        reinterpret_cast<ol_platform_handle_t *>(InfoData.data());
+    ASSERT_EQ(Platform, *ReturnedPlatform);
+  }
+}
+
+TEST_F(olGetDeviceInfoTest, InvalidNullHandleDevice) {
+  ol_device_type_t DeviceType;
+  ASSERT_ERROR(OL_ERRC_INVALID_NULL_HANDLE,
+               olGetDeviceInfo(nullptr, OL_DEVICE_INFO_TYPE,
+                               sizeof(ol_device_type_t), &DeviceType));
+}
+
+TEST_F(olGetDeviceInfoTest, InvalidEnumerationInfoType) {
+  ol_device_type_t DeviceType;
+  ASSERT_ERROR(OL_ERRC_INVALID_ENUMERATION,
+               olGetDeviceInfo(Device, OL_DEVICE_INFO_FORCE_UINT32,
+                               sizeof(ol_device_type_t), &DeviceType));
+}
+
+TEST_F(olGetDeviceInfoTest, InvalidSizePropSize) {
+  ol_device_type_t DeviceType;
+  ASSERT_ERROR(OL_ERRC_INVALID_SIZE,
+               olGetDeviceInfo(Device, OL_DEVICE_INFO_TYPE, 0, &DeviceType));
+}
+
+TEST_F(olGetDeviceInfoTest, InvalidSizePropSizeSmall) {
+  ol_device_type_t DeviceType;
+  ASSERT_ERROR(OL_ERRC_INVALID_SIZE,
+               olGetDeviceInfo(Device, OL_DEVICE_INFO_TYPE,
+                               sizeof(DeviceType) - 1, &DeviceType));
+}
+
+TEST_F(olGetDeviceInfoTest, InvalidNullPointerPropValue) {
+  ol_device_type_t DeviceType;
+  ASSERT_ERROR(OL_ERRC_INVALID_NULL_POINTER,
+               olGetDeviceInfo(Device, OL_DEVICE_INFO_TYPE, sizeof(DeviceType),
+                               nullptr));
+}
diff --git a/offload/unittests/OffloadAPI/device/olGetDeviceInfoSize.cpp b/offload/unittests/OffloadAPI/device/olGetDeviceInfoSize.cpp
new file mode 100644
index 0000000..9e792d1c
--- /dev/null
+++ b/offload/unittests/OffloadAPI/device/olGetDeviceInfoSize.cpp
@@ -0,0 +1,58 @@
+//===------- Offload API tests - olGetDeviceInfoSize -----------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#include <OffloadAPI.h>
+
+#include "../common/Fixtures.hpp"
+#include "olDeviceInfo.hpp"
+
+struct olGetDeviceInfoSizeTest
+    : offloadDeviceTest,
+      ::testing::WithParamInterface<ol_device_info_t> {
+
+  void SetUp() override { RETURN_ON_FATAL_FAILURE(offloadDeviceTest::SetUp()); }
+};
+
+// TODO: We could autogenerate the list of enum values
+INSTANTIATE_TEST_SUITE_P(
+    , olGetDeviceInfoSizeTest, ::testing::ValuesIn(DeviceQueries),
+    [](const ::testing::TestParamInfo<ol_device_info_t> &info) {
+      std::stringstream ss;
+      ss << info.param;
+      return ss.str();
+    });
+
+TEST_P(olGetDeviceInfoSizeTest, Success) {
+  ol_device_info_t InfoType = GetParam();
+  size_t Size = 0;
+
+  ASSERT_SUCCESS(olGetDeviceInfoSize(Device, InfoType, &Size));
+  auto ExpectedSize = DeviceInfoSizeMap.find(InfoType);
+  if (ExpectedSize != DeviceInfoSizeMap.end()) {
+    ASSERT_EQ(Size, ExpectedSize->second);
+  } else {
+    ASSERT_NE(Size, 0lu);
+  }
+}
+
+TEST_F(olGetDeviceInfoSizeTest, InvalidNullHandle) {
+  size_t Size = 0;
+  ASSERT_ERROR(OL_ERRC_INVALID_NULL_HANDLE,
+               olGetDeviceInfoSize(nullptr, OL_DEVICE_INFO_TYPE, &Size));
+}
+
+TEST_F(olGetDeviceInfoSizeTest, InvalidDeviceInfoEnumeration) {
+  size_t Size = 0;
+  ASSERT_ERROR(OL_ERRC_INVALID_ENUMERATION,
+               olGetDeviceInfoSize(Device, OL_DEVICE_INFO_FORCE_UINT32, &Size));
+}
+
+TEST_F(olGetDeviceInfoSizeTest, InvalidNullPointer) {
+  ASSERT_ERROR(OL_ERRC_INVALID_NULL_POINTER,
+               olGetDeviceInfoSize(Device, OL_DEVICE_INFO_TYPE, nullptr));
+}