[cuda] Implement basics for a CUDA HAL driver rewrite (#13942)

This commit starts a CUDA HAL driver rewrite under `experimental/`.
We create a new `cuda2/` directory to host the new code to avoid
interrupting the current CodeGen development.

This commit just brings in the basics for boot up a new HAL driver,
including dynamic symbols management, error status management, and
IREE HAL driver implementation. Most of the code is directly copied
from existing HAL driver, with noticeable changes:

* Split CUDA and NCCL dynamic symbols into separate structures for
  better organziation and allowing optionality.
* Fleshed out CUDA error to IREE status conversions.
* Better organized code blocks and improved error messages and
  various comments.

Building this commmit with `-DIREE_EXTERNAL_HAL_DRIVERS=cuda2`,
we can have `tools/iree-run-module --dump_devices` showing `cuda2`
devices, in parallel to the existing CUDA one.

Progress towards #13245

CMakeLists.txt

@@ -308,6 +308,15 @@ if(IREE_HAL_EXECUTABLE_PLUGIN_SYSTEM_LIBRARY)
   message(STATUS "  - system-library")
 endif()
 
+#-------------------------------------------------------------------------------
+# Experimental next-generation CUDA HAL driver
+#-------------------------------------------------------------------------------
+
+set(IREE_EXTERNAL_CUDA2_HAL_DRIVER_SOURCE_DIR "${CMAKE_CURRENT_SOURCE_DIR}/experimental/cuda2")
+set(IREE_EXTERNAL_CUDA2_HAL_DRIVER_BINARY_DIR "${CMAKE_CURRENT_BINARY_DIR}/experimental/cuda2")
+set(IREE_EXTERNAL_CUDA2_HAL_DRIVER_TARGET "iree::experimental::cuda2::registration")
+set(IREE_EXTERNAL_CUDA2_HAL_DRIVER_REGISTER "iree_hal_cuda2_driver_module_register")
+
 #-------------------------------------------------------------------------------
 # Experimental ROCM HAL driver
 #-------------------------------------------------------------------------------

experimental/cuda2/CMakeLists.txt

@@ -0,0 +1,64 @@
+# Copyright 2023 The IREE Authors
+#
+# Licensed 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
+
+# Set the root for package namespacing to the current directory.
+set(IREE_PACKAGE_ROOT_DIR "${CMAKE_CURRENT_LIST_DIR}")
+set(IREE_PACKAGE_ROOT_PREFIX "iree/experimental/cuda2")
+
+iree_add_all_subdirs()
+
+iree_cc_library(
+  NAME
+    cuda2
+  HDRS
+    "api.h"
+  SRCS
+    "api.h"
+    "cuda_driver.c"
+  DEPS
+    ::dynamic_symbols
+    iree::base
+    iree::base::core_headers
+    iree::base::tracing
+    iree::hal
+    iree::schemas::cuda_executable_def_c_fbs
+  PUBLIC
+)
+
+iree_cc_library(
+  NAME
+    dynamic_symbols
+  HDRS
+    "dynamic_symbols.h"
+    "status_util.h"
+  TEXTUAL_HDRS
+    "dynamic_symbol_tables.h"
+  SRCS
+    "cuda_headers.h"
+    "dynamic_symbols.c"
+    "status_util.c"
+  DEPS
+    iree::base
+    iree::base::core_headers
+    iree::base::internal::dynamic_library
+    iree::base::tracing
+    iree_cuda::headers
+  PUBLIC
+)
+
+iree_cc_test(
+  NAME
+    dynamic_symbols_test
+  SRCS
+    "dynamic_symbols_test.cc"
+  DEPS
+    ::dynamic_symbols
+    iree::base
+    iree::testing::gtest
+    iree::testing::gtest_main
+  LABELS
+    "driver=cuda2"
+)

experimental/cuda2/api.h

@@ -0,0 +1,47 @@
+// Copyright 2023 The IREE Authors
+//
+// Licensed 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
+
+// See iree/base/api.h for documentation on the API conventions used.
+
+#ifndef IREE_EXPERIMENTAL_CUDA2_API_H_
+#define IREE_EXPERIMENTAL_CUDA2_API_H_
+
+#include "iree/base/api.h"
+#include "iree/hal/api.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif  // __cplusplus
+
+//===----------------------------------------------------------------------===//
+// iree_hal_cuda2_driver_t
+//===----------------------------------------------------------------------===//
+
+// CUDA HAL driver creation options.
+typedef struct iree_hal_cuda2_driver_options_t {
+  // The index of the default CUDA device to use within the list of available
+  // devices.
+  int default_device_index;
+} iree_hal_cuda2_driver_options_t;
+
+// Initializes the given |out_options| with default driver creation options.
+IREE_API_EXPORT void iree_hal_cuda2_driver_options_initialize(
+    iree_hal_cuda2_driver_options_t* out_options);
+
+// Creates a CUDA HAL driver with the given |options|, from which CUDA devices
+// can be enumerated and created with specific parameters.
+//
+// |out_driver| must be released by the caller (see iree_hal_driver_release).
+IREE_API_EXPORT iree_status_t iree_hal_cuda2_driver_create(
+    iree_string_view_t identifier,
+    const iree_hal_cuda2_driver_options_t* options,
+    iree_allocator_t host_allocator, iree_hal_driver_t** out_driver);
+
+#ifdef __cplusplus
+}  // extern "C"
+#endif  // __cplusplus
+
+#endif  // IREE_EXPERIMENTAL_CUDA2_API_H_