1 files changed, 106 insertions, 0 deletions
diff --git a/mlir/tools/mlir-cuda-runner/cuda-runtime-wrappers.cpp b/mlir/tools/mlir-cuda-runner/cuda-runtime-wrappers.cpp
new file mode 100644
index 00000000000..9f1591b5a8c
--- /dev/null
+++ b/mlir/tools/mlir-cuda-runner/cuda-runtime-wrappers.cpp
@@ -0,0 +1,106 @@
+//===- cuda-runtime-wrappers.cpp - MLIR CUDA runner wrapper library -------===//
+//
+// Part of the MLIR 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
+//
+//===----------------------------------------------------------------------===//
+//
+// Implements C wrappers around the CUDA library for easy linking in ORC jit.
+// Also adds some debugging helpers that are helpful when writing MLIR code to
+// run on GPUs.
+//
+//===----------------------------------------------------------------------===//
+
+#include <cassert>
+#include <numeric>
+
+#include "llvm/Support/raw_ostream.h"
+
+#include "cuda.h"
+
+namespace {
+int32_t reportErrorIfAny(CUresult result, const char *where) {
+  if (result != CUDA_SUCCESS) {
+    llvm::errs() << "CUDA failed with " << result << " in " << where << "\n";
+  }
+  return result;
+}
+} // anonymous namespace
+
+extern "C" int32_t mcuModuleLoad(void **module, void *data) {
+  int32_t err = reportErrorIfAny(
+      cuModuleLoadData(reinterpret_cast<CUmodule *>(module), data),
+      "ModuleLoad");
+  return err;
+}
+
+extern "C" int32_t mcuModuleGetFunction(void **function, void *module,
+                                        const char *name) {
+  return reportErrorIfAny(
+      cuModuleGetFunction(reinterpret_cast<CUfunction *>(function),
+                          reinterpret_cast<CUmodule>(module), name),
+      "GetFunction");
+}
+
+// The wrapper uses intptr_t instead of CUDA's unsigned int to match
+// the type of MLIR's index type. This avoids the need for casts in the
+// generated MLIR code.
+extern "C" int32_t mcuLaunchKernel(void *function, intptr_t gridX,
+                                   intptr_t gridY, intptr_t gridZ,
+                                   intptr_t blockX, intptr_t blockY,
+                                   intptr_t blockZ, int32_t smem, void *stream,
+                                   void **params, void **extra) {
+  return reportErrorIfAny(
+      cuLaunchKernel(reinterpret_cast<CUfunction>(function), gridX, gridY,
+                     gridZ, blockX, blockY, blockZ, smem,
+                     reinterpret_cast<CUstream>(stream), params, extra),
+      "LaunchKernel");
+}
+
+extern "C" void *mcuGetStreamHelper() {
+  CUstream stream;
+  reportErrorIfAny(cuStreamCreate(&stream, CU_STREAM_DEFAULT), "StreamCreate");
+  return stream;
+}
+
+extern "C" int32_t mcuStreamSynchronize(void *stream) {
+  return reportErrorIfAny(
+      cuStreamSynchronize(reinterpret_cast<CUstream>(stream)), "StreamSync");
+}
+
+/// Helper functions for writing mlir example code
+
+// Allows to register byte array with the CUDA runtime. Helpful until we have
+// transfer functions implemented.
+extern "C" void mcuMemHostRegister(void *ptr, uint64_t sizeBytes) {
+  reportErrorIfAny(cuMemHostRegister(ptr, sizeBytes, /*flags=*/0),
+                   "MemHostRegister");
+}
+
+// A struct that corresponds to how MLIR represents memrefs.
+template <typename T, int N> struct MemRefType {
+  T *basePtr;
+  T *data;
+  int64_t offset;
+  int64_t sizes[N];
+  int64_t strides[N];
+};
+
+// Allows to register a MemRef with the CUDA runtime. Initializes array with
+// value. Helpful until we have transfer functions implemented.
+template <typename T, int N>
+void mcuMemHostRegisterMemRef(const MemRefType<T, N> *arg, T value) {
+  auto count = std::accumulate(arg->sizes, arg->sizes + N, 1,
+                               std::multiplies<int64_t>());
+  std::fill_n(arg->data, count, value);
+  mcuMemHostRegister(arg->data, count * sizeof(T));
+}
+extern "C" void
+mcuMemHostRegisterMemRef1dFloat(const MemRefType<float, 1> *arg) {
+  mcuMemHostRegisterMemRef(arg, 1.23f);
+}
+extern "C" void
+mcuMemHostRegisterMemRef3dFloat(const MemRefType<float, 3> *arg) {
+  mcuMemHostRegisterMemRef(arg, 1.23f);
+}