Cycles: Metal host-side code

This patch adds the Metal host-side code:

- Add all core host-side Metal backend files (device_impl, queue, etc)
- Add MetalRT BVH setup files
- Integrate with Cycles device enumeration code
- Revive `path_source_replace_includes` in util/path (required for MSL compilation)

This patch also includes a couple of small kernel-side fixes:

- Add an implementation of `lgammaf` for Metal [Nemes, Gergő (2010), "New asymptotic expansion for the Gamma function", Archiv der Mathematik](https://users.renyi.hu/~gergonemes/)
- include "work_stealing.h" inside the Metal context class because it accesses state now

Ref T92212

Reviewed By: brecht

Maniphest Tasks: T92212

Differential Revision: https://developer.blender.org/D13423

1 files changed, 37 insertions, 0 deletions

diff --git a/intern/cycles/device/metal/device.h b/intern/cycles/device/metal/device.h
new file mode 100644
index 00000000000..254fbfee42b
--- /dev/null
+++ b/intern/cycles/device/metal/device.h
@@ -0,0 +1,37 @@
+/*
+ * Copyright 2021 Blender Foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#pragma once
+
+#include "util/string.h"
+#include "util/vector.h"
+
+CCL_NAMESPACE_BEGIN
+
+class Device;
+class DeviceInfo;
+class Profiler;
+class Stats;
+
+bool device_metal_init();
+
+Device *device_metal_create(const DeviceInfo &info, Stats &stats, Profiler &profiler);
+
+void device_metal_info(vector<DeviceInfo> &devices);
+
+string device_metal_capabilities();
+
+CCL_NAMESPACE_END