Provide SSSE3, AVX2, and AVX512 optimized Reed-Solomon functions

cmake/compile_definitions/common.cmake

@@ -49,8 +49,6 @@ configure_file("${CMAKE_SOURCE_DIR}/src/version.h.in" version.h @ONLY)
 include_directories("${CMAKE_CURRENT_BINARY_DIR}")  # required for importing version.h
 
 set(SUNSHINE_TARGET_FILES
-        "${CMAKE_SOURCE_DIR}/third-party/nanors/rs.c"
-        "${CMAKE_SOURCE_DIR}/third-party/nanors/rs.h"
         "${CMAKE_SOURCE_DIR}/third-party/moonlight-common-c/src/Input.h"
         "${CMAKE_SOURCE_DIR}/third-party/moonlight-common-c/src/Rtsp.h"
         "${CMAKE_SOURCE_DIR}/third-party/moonlight-common-c/src/RtspParser.c"
@@ -108,6 +106,8 @@ set(SUNSHINE_TARGET_FILES
         "${CMAKE_SOURCE_DIR}/src/round_robin.h"
         "${CMAKE_SOURCE_DIR}/src/stat_trackers.h"
         "${CMAKE_SOURCE_DIR}/src/stat_trackers.cpp"
+        "${CMAKE_SOURCE_DIR}/src/rswrapper.h"
+        "${CMAKE_SOURCE_DIR}/src/rswrapper.c"
         ${PLATFORM_TARGET_FILES})
 
 if(NOT SUNSHINE_ASSETS_DIR_DEF)

cmake/targets/common.cmake

@@ -85,9 +85,9 @@ set_source_files_properties("${CMAKE_SOURCE_DIR}/src/upnp.cpp"
         PROPERTIES COMPILE_FLAGS -Wno-pedantic)
 
 # third-party/nanors
-set_source_files_properties("${CMAKE_SOURCE_DIR}/third-party/nanors/rs.c"
+set_source_files_properties("${CMAKE_SOURCE_DIR}/src/rswrapper.c"
         DIRECTORY "${CMAKE_SOURCE_DIR}" "${TEST_DIR}"
-        PROPERTIES COMPILE_FLAGS "-include deps/obl/autoshim.h -ftree-vectorize")
+        PROPERTIES COMPILE_FLAGS "-ftree-vectorize -funroll-loops")
 
 # third-party/ViGEmClient
 set(VIGEM_COMPILE_FLAGS "")

src/main.cpp

@@ -23,7 +23,7 @@
 #include "video.h"
 
 extern "C" {
-#include <rs.h>
+#include "rswrapper.h"
 }
 
 using namespace std::literals;

src/rswrapper.c

@@ -0,0 +1,157 @@
+/**
+ * @file src/rswrapper.c
+ * @brief Wrappers for nanors vectorization with different ISA options
+ */
+
+// _FORTIY_SOURCE can cause some versions of GCC to try to inline
+// memset() with incompatible target options when compiling rs.c
+#ifdef _FORTIFY_SOURCE
+  #undef _FORTIFY_SOURCE
+#endif
+
+// The assert() function is decorated with __cold on macOS which
+// is incompatible with Clang's target multiversioning feature
+#ifndef NDEBUG
+  #define NDEBUG
+#endif
+
+#define DECORATE_FUNC_I(a, b) a##b
+#define DECORATE_FUNC(a, b) DECORATE_FUNC_I(a, b)
+
+// Append an ISA suffix to the public RS API
+#define reed_solomon_init DECORATE_FUNC(reed_solomon_init, ISA_SUFFIX)
+#define reed_solomon_new DECORATE_FUNC(reed_solomon_new, ISA_SUFFIX)
+#define reed_solomon_new_static DECORATE_FUNC(reed_solomon_new_static, ISA_SUFFIX)
+#define reed_solomon_release DECORATE_FUNC(reed_solomon_release, ISA_SUFFIX)
+#define reed_solomon_decode DECORATE_FUNC(reed_solomon_decode, ISA_SUFFIX)
+#define reed_solomon_encode DECORATE_FUNC(reed_solomon_encode, ISA_SUFFIX)
+
+// Append an ISA suffix to internal functions to prevent multiple definition errors
+#define obl_axpy_ref DECORATE_FUNC(obl_axpy_ref, ISA_SUFFIX)
+#define obl_scal_ref DECORATE_FUNC(obl_scal_ref, ISA_SUFFIX)
+#define obl_axpyb32_ref DECORATE_FUNC(obl_axpyb32_ref, ISA_SUFFIX)
+#define obl_axpy DECORATE_FUNC(obl_axpy, ISA_SUFFIX)
+#define obl_scal DECORATE_FUNC(obl_scal, ISA_SUFFIX)
+#define obl_swap DECORATE_FUNC(obl_swap, ISA_SUFFIX)
+#define obl_axpyb32 DECORATE_FUNC(obl_axpyb32, ISA_SUFFIX)
+#define axpy DECORATE_FUNC(axpy, ISA_SUFFIX)
+#define scal DECORATE_FUNC(scal, ISA_SUFFIX)
+#define gemm DECORATE_FUNC(gemm, ISA_SUFFIX)
+#define invert_mat DECORATE_FUNC(invert_mat, ISA_SUFFIX)
+
+#if defined(__x86_64__) || defined(__i386__)
+
+  // Compile a variant for SSSE3
+  #if defined(__clang__)
+    #pragma clang attribute push(__attribute__((target("ssse3"))), apply_to = function)
+  #else
+    #pragma GCC push_options
+    #pragma GCC target("ssse3")
+  #endif
+  #define ISA_SUFFIX _ssse3
+  #define OBLAS_SSE3
+  #include "../third-party/nanors/rs.c"
+  #undef OBLAS_SSE3
+  #undef ISA_SUFFIX
+  #if defined(__clang__)
+    #pragma clang attribute pop
+  #else
+    #pragma GCC pop_options
+  #endif
+
+  // Compile a variant for AVX2
+  #if defined(__clang__)
+    #pragma clang attribute push(__attribute__((target("avx2"))), apply_to = function)
+  #else
+    #pragma GCC push_options
+    #pragma GCC target("avx2")
+  #endif
+  #define ISA_SUFFIX _avx2
+  #define OBLAS_AVX2
+  #include "../third-party/nanors/rs.c"
+  #undef OBLAS_AVX2
+  #undef ISA_SUFFIX
+  #if defined(__clang__)
+    #pragma clang attribute pop
+  #else
+    #pragma GCC pop_options
+  #endif
+
+  // Compile a variant for AVX512BW
+  #if defined(__clang__)
+    #pragma clang attribute push(__attribute__((target("avx512f,avx512bw"))), apply_to = function)
+  #else
+    #pragma GCC push_options
+    #pragma GCC target("avx512f,avx512bw")
+  #endif
+  #define ISA_SUFFIX _avx512
+  #define OBLAS_AVX512
+  #include "../third-party/nanors/rs.c"
+  #undef OBLAS_AVX512
+  #undef ISA_SUFFIX
+  #if defined(__clang__)
+    #pragma clang attribute pop
+  #else
+    #pragma GCC pop_options
+  #endif
+
+#endif
+
+// Compile a default variant
+#define ISA_SUFFIX _def
+#include "../third-party/nanors/deps/obl/autoshim.h"
+#include "../third-party/nanors/rs.c"
+#undef ISA_SUFFIX
+
+#undef reed_solomon_init
+#undef reed_solomon_new
+#undef reed_solomon_new_static
+#undef reed_solomon_release
+#undef reed_solomon_decode
+#undef reed_solomon_encode
+
+#include "rswrapper.h"
+
+reed_solomon_new_t reed_solomon_new_fn;
+reed_solomon_release_t reed_solomon_release_fn;
+reed_solomon_encode_t reed_solomon_encode_fn;
+reed_solomon_decode_t reed_solomon_decode_fn;
+
+/**
+ * @brief This initializes the RS function pointers to the best vectorized version available.
+ * @details The streaming code will directly invoke these function pointers during encoding.
+ */
+void
+reed_solomon_init(void) {
+#if defined(__x86_64__) || defined(__i386__)
+  if (__builtin_cpu_supports("avx512f") && __builtin_cpu_supports("avx512bw")) {
+    reed_solomon_new_fn = reed_solomon_new_avx512;
+    reed_solomon_release_fn = reed_solomon_release_avx512;
+    reed_solomon_encode_fn = reed_solomon_encode_avx512;
+    reed_solomon_decode_fn = reed_solomon_decode_avx512;
+    reed_solomon_init_avx512();
+  }
+  else if (__builtin_cpu_supports("avx2")) {
+    reed_solomon_new_fn = reed_solomon_new_avx2;
+    reed_solomon_release_fn = reed_solomon_release_avx2;
+    reed_solomon_encode_fn = reed_solomon_encode_avx2;
+    reed_solomon_decode_fn = reed_solomon_decode_avx2;
+    reed_solomon_init_avx2();
+  }
+  else if (__builtin_cpu_supports("ssse3")) {
+    reed_solomon_new_fn = reed_solomon_new_ssse3;
+    reed_solomon_release_fn = reed_solomon_release_ssse3;
+    reed_solomon_encode_fn = reed_solomon_encode_ssse3;
+    reed_solomon_decode_fn = reed_solomon_decode_ssse3;
+    reed_solomon_init_ssse3();
+  }
+  else
+#endif
+  {
+    reed_solomon_new_fn = reed_solomon_new_def;
+    reed_solomon_release_fn = reed_solomon_release_def;
+    reed_solomon_encode_fn = reed_solomon_encode_def;
+    reed_solomon_decode_fn = reed_solomon_decode_def;
+    reed_solomon_init_def();
+  }
+}

src/rswrapper.h

@@ -0,0 +1,32 @@
+/**
+ * @file src/rswrapper.h
+ * @brief Wrappers for nanors vectorization
+ * @details This is a drop-in replacement for nanors rs.h
+ */
+#pragma once
+
+#include <stdint.h>
+
+typedef struct _reed_solomon reed_solomon;
+
+typedef reed_solomon *(*reed_solomon_new_t)(int data_shards, int parity_shards);
+typedef void (*reed_solomon_release_t)(reed_solomon *rs);
+typedef int (*reed_solomon_encode_t)(reed_solomon *rs, uint8_t **shards, int nr_shards, int bs);
+typedef int (*reed_solomon_decode_t)(reed_solomon *rs, uint8_t **shards, uint8_t *marks, int nr_shards, int bs);
+
+extern reed_solomon_new_t reed_solomon_new_fn;
+extern reed_solomon_release_t reed_solomon_release_fn;
+extern reed_solomon_encode_t reed_solomon_encode_fn;
+extern reed_solomon_decode_t reed_solomon_decode_fn;
+
+#define reed_solomon_new reed_solomon_new_fn
+#define reed_solomon_release reed_solomon_release_fn
+#define reed_solomon_encode reed_solomon_encode_fn
+#define reed_solomon_decode reed_solomon_decode_fn
+
+/**
+ * @brief This initializes the RS function pointers to the best vectorized version available.
+ * @details The streaming code will directly invoke these function pointers during encoding.
+ */
+void
+reed_solomon_init(void);

src/stream.cpp

@@ -13,8 +13,10 @@
 #include <boost/endian/arithmetic.hpp>
 
 extern "C" {
+// clang-format off
 #include <moonlight-common-c/src/Limelight-internal.h>
-#include <rs.h>
+#include "rswrapper.h"
+// clang-format on
 }
 
 #include "config.h"
@@ -236,7 +238,6 @@ namespace stream {
   }
   constexpr std::size_t MAX_AUDIO_PACKET_SIZE = 1400;
 
-  using rh_t = util::safe_ptr<reed_solomon, reed_solomon_release>;
   using video_packet_t = util::c_ptr<video_packet_raw_t>;
   using audio_packet_t = util::c_ptr<audio_packet_raw_t>;
   using audio_fec_packet_t = util::c_ptr<audio_fec_packet_raw_t>;
@@ -621,7 +622,7 @@ namespace stream {
   }
 
   namespace fec {
-    using rs_t = util::safe_ptr<reed_solomon, reed_solomon_release>;
+    using rs_t = util::safe_ptr<reed_solomon, [](reed_solomon *rs) { reed_solomon_release(rs); }>;
 
     struct fec_t {
       size_t data_shards;

tests/unit/test_rswrapper.cpp

@@ -0,0 +1,37 @@
+/**
+ * @file tests/unit/test_rswrapper.cpp
+ * @brief Test src/rswrapper.*
+ */
+
+extern "C" {
+#include <src/rswrapper.h>
+}
+
+#include <tests/conftest.cpp>
+
+TEST(ReedSolomonWrapperTests, InitTest) {
+  reed_solomon_init();
+
+  // Ensure all function pointers were populated
+  ASSERT_NE(reed_solomon_new, nullptr);
+  ASSERT_NE(reed_solomon_release, nullptr);
+  ASSERT_NE(reed_solomon_encode, nullptr);
+  ASSERT_NE(reed_solomon_decode, nullptr);
+}
+
+TEST(ReedSolomonWrapperTests, EncodeTest) {
+  reed_solomon_init();
+
+  auto rs = reed_solomon_new(1, 1);
+  ASSERT_NE(rs, nullptr);
+
+  uint8_t dataShard[16] = {};
+  uint8_t fecShard[16] = {};
+
+  // If we picked the incorrect ISA in our wrapper, we should crash here
+  uint8_t *shardPtrs[2] = { dataShard, fecShard };
+  auto ret = reed_solomon_encode(rs, shardPtrs, 2, sizeof(dataShard));
+  ASSERT_EQ(ret, 0);
+
+  reed_solomon_release(rs);
+}