Add Windows/MSVC support (flashlight#1107)

Summary:
Implement changes to support compilation with MSVC. This tests the Flashlight core with MSVC 2019; won't expand to apps/pkgs for now/will gate compilation given dependencies therein that aren't supported on Windows.

Required changes include:
- initialize the `flashlight` target after compiler options are set, and move those up. Eventually, this should probably be public properties of the `flashlight` target
- Add `\bigobj` as an MSVC compiler option since we aren't currently explicitly exporting symbols
- Don't bother checking for `-rdynamic` with windows because I don't want to support plugins for it anyways
- Introduce `FL_BUILD_PLUGIN` as a set option per the above to enforce the correct behavior
- Swap from `math.h` to `cmath` and compile with required `_USE_MATH_DEFINES` and `NOMINMAX` for `M_PI` and friends
- MSVC hates implicit overloads that cast from `std::string` to `std::filesystem::path` in argument lists (when used as refs) -- change the FL serialization API to rely on `fs::path` as the arg
- missing headers throughout
- some missing lambda captures that gcc/clang totally ignored
- MSVC 2019 doesn't allow aggregate initialization, sad
- don't check and optionally use `std::filesystem` linker flags with MSVC; no additional linking is required

Pull Request resolved: flashlight#1107

Test Plan: local compilation with MSVC 2019 on Windows 11, test with toy CI baselines

Reviewed By: bwasti

Differential Revision: D46080426

Pulled By: jacobkahn

fbshipit-source-id: f006e68aea9d798da72621e5d7538752e786d99b

.gitignore

@@ -51,3 +51,5 @@ wheels/
 
 # Dev environment
 .vscode
+.vs
+CMakeSettings.json

CMakeLists.txt

@@ -15,6 +15,13 @@ list(APPEND CMAKE_MODULE_PATH "${CMAKE_CURRENT_SOURCE_DIR}/cmake")
 set(CMAKE_CXX_STANDARD 17)
 set(CMAKE_CXX_STANDARD_REQUIRED ON)
 
+# The CUDA standard is still C++14 to enable interopability with
+# slightly older and still well-supported versions of CUDA/nvcc
+# (e.g. CUDA < 11). This will be bumped to 17 once CUDA 11 is
+# required.
+set(CMAKE_CUDA_STANDARD 14)
+set(CMAKE_CUDA_STANDARD_REQUIRED ON)
+
 # Default directories for installation
 set(FL_INSTALL_INC_DIR "include" CACHE PATH "Install path for headers")
 set(FL_INSTALL_INC_DIR_HEADER_LOC ${FL_INSTALL_INC_DIR}/flashlight)
@@ -35,9 +42,23 @@ if(${COMPILER_SUPPORTS_RDYNAMIC})
   set(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} -rdynamic")
   set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} -rdynamic")
 else()
-  message(WARNING
-    "This compiler doesn't support dynamic symbol exports. "
-    "Plugin functionality likely won't work.")
+  if (NOT WIN32) # Windows operates with explicit dll exports
+    message(WARNING
+      "This compiler doesn't support dynamic symbol exports. "
+      "Plugin functionality likely won't work.")
+  endif()
+endif()
+set(FL_BUILD_PLUGIN ${COMPILER_SUPPORTS_RDYNAMIC})
+
+# ]------ The library target for the Flashlight core
+add_library(flashlight)
+
+# We haven't [yet] polluted Flashlight with explicit dllexport annotations
+if (MSVC)
+  target_compile_options(flashlight PUBLIC $<$<NOT:$<COMPILE_LANGUAGE:CUDA>>:/bigobj>)
+endif()
+if (WIN32)
+  target_compile_definitions(flashlight PUBLIC _USE_MATH_DEFINES NOMINMAX)
 endif()
 
 include(InternalUtils)
@@ -73,16 +94,7 @@ option(FL_USE_CPU    "Build CPU support for Flashlight backends"  OFF)
 option(FL_USE_OPENCL "Build OpenCL support for Flashlight backends" OFF)
 option(FL_USE_MKL    "Build MKL support for Flashlight backends" OFF)
 
-# The CUDA standard is still C++14 to enable interopability with
-# slightly older and still well-supported versions of CUDA/nvcc
-# (e.g. CUDA < 11). This will be bumped to 17 once CUDA 11 is
-# required.
-set(CMAKE_CUDA_STANDARD 14)
-set(CMAKE_CUDA_STANDARD_REQUIRED ON)
-
 # --------------------------- Core ---------------------------
-add_library(flashlight)
-
 # Internal includes are implicitly defined as <flashlight...>
 target_include_directories(
   flashlight

flashlight/fl/common/CMakeLists.txt

@@ -9,18 +9,34 @@ target_sources(
   ${CMAKE_CURRENT_LIST_DIR}/DynamicBenchmark.cpp
   ${CMAKE_CURRENT_LIST_DIR}/Logging.cpp
   ${CMAKE_CURRENT_LIST_DIR}/Histogram.cpp
-  ${CMAKE_CURRENT_LIST_DIR}/Plugin.cpp
   ${CMAKE_CURRENT_LIST_DIR}/Timer.cpp
 )
 
+if (${FL_BUILD_PLUGIN})
+  target_sources(flashlight PRIVATE ${CMAKE_CURRENT_LIST_DIR}/Plugin.cpp)
+else()
+  message(WARNING "Compiler doesn't support -rdynamic - not building Plugin")
+endif()
+
 # A native threading library
 find_package(Threads REQUIRED)
 target_link_libraries(flashlight PUBLIC Threads::Threads)
 
 # Dynamic lib loading needed for Plugins
 target_link_libraries(flashlight PUBLIC ${CMAKE_DL_LIBS})
 
-# std::filesystem -- remove this when requiring gcc >= 9
-find_package(Filesystem REQUIRED COMPONENTS Final Experimental)
-setup_install_find_module(${PROJECT_SOURCE_DIR}/cmake/FindFilesystem.cmake)
-target_link_libraries(flashlight PUBLIC std::filesystem)
+# To support __VA_ARGS__ for serialization macros
+if (MSVC)
+  if (MSVC_VERSION LESS 1920)
+    target_compile_options(flashlight PUBLIC $<$<COMPILE_LANGUAGE:C,CXX>:/experimental:preprocessor>) # MSVC 2017
+  else()
+    target_compile_options(flashlight PUBLIC $<$<COMPILE_LANGUAGE:C,CXX>:/Zc:preprocessor>) # MSVC 2019+
+  endif()
+endif()
+
+# std::filesystem linking -- remove this when requiring gcc >= 9
+if (NOT MSVC)
+  find_package(Filesystem REQUIRED COMPONENTS Final Experimental)
+  setup_install_find_module(${CMAKE_MODULE_PATH}/FindFilesystem.cmake)
+  target_link_libraries(flashlight PUBLIC std::filesystem)
+endif()

flashlight/fl/common/Serialization-inl.h

@@ -15,6 +15,7 @@
 #include <type_traits>
 #include <utility>
 
+#include "flashlight/fl/common/Filesystem.h"
 #include "flashlight/fl/tensor/TensorBase.h"
 
 #pragma once
@@ -128,7 +129,7 @@ serializeAs(T&& t, SaveConvFn saveConverter, LoadConvFn loadConverter) {
 }
 
 template <typename... Args>
-void save(const std::string& filepath, const Args&... args) {
+void save(const fs::path& filepath, const Args&... args) {
   std::ofstream ofs(filepath, std::ios::binary);
   save(ofs, args...);
 }
@@ -140,7 +141,7 @@ void save(std::ostream& ostr, const Args&... args) {
 }
 
 template <typename... Args>
-void load(const std::string& filepath, Args&... args) {
+void load(const fs::path& filepath, Args&... args) {
   std::ifstream ifs(filepath, std::ios::binary);
   load(ifs, args...);
 }
@@ -189,7 +190,8 @@ void save(
 
 template <class Archive>
 void load(Archive& ar, fl::Shape& dims, const uint32_t /* version */) {
-  // TODO{fl::Tensor} -- check version, then read dim4 into Shape (if version ==)
+  // TODO{fl::Tensor} -- check version, then read dim4 into Shape (if version
+  // ==)
   std::vector<fl::Dim> vec;
   ar(vec);
   dims = fl::Shape(vec);

flashlight/fl/common/Serialization.h

@@ -15,6 +15,7 @@
 #include <iostream>
 #include <type_traits>
 
+#include "flashlight/fl/common/Filesystem.h"
 #include "flashlight/fl/tensor/TensorBase.h"
 
 #include <cereal/access.hpp>
@@ -54,7 +55,7 @@ namespace fl {
  * @param args the objects to save (e.g. shared_ptr to Module)
  */
 template <typename... Args>
-void save(const std::string& filepath, const Args&... args);
+void save(const fs::path& filepath, const Args&... args);
 
 /**
  * Save (serialize) the specified args to a binary file (via Cereal).
@@ -70,7 +71,7 @@ void save(std::ostream& ostr, const Args&... args);
  * @param args the objects to load (expects default-constructed)
  */
 template <typename... Args>
-void load(const std::string& filepath, Args&... args);
+void load(const fs::path& filepath, Args&... args);
 
 /**
  * Load (deserialize) the specified args from a binary file (via Cereal).

flashlight/fl/contrib/modules/RawWavSpecAugment.cpp

@@ -5,9 +5,10 @@
  * LICENSE file in the root directory of this source tree.
  */
 
-#include <math.h>
+#include <cmath>
 #include <sstream>
 #include <stdexcept>
+#include <numeric>
 
 #include "flashlight/fl/common/Logging.h"
 #include "flashlight/fl/contrib/modules/RawWavSpecAugment.h"

flashlight/fl/contrib/modules/SinusoidalPositionEmbedding.cpp

@@ -7,8 +7,11 @@
 
 #include "flashlight/fl/contrib/modules/SinusoidalPositionEmbedding.h"
 
-#include <math.h>
+#include <cmath>
 #include <stdexcept>
+#include <algorithm>
+#include <numeric>
+
 #include "flashlight/fl/autograd/Functions.h"
 #include "flashlight/fl/nn/Init.h"
 #include "flashlight/fl/nn/Utils.h"

flashlight/fl/dataset/FileBlobDataset.cpp

@@ -5,20 +5,22 @@
  * LICENSE file in the root directory of this source tree.
  */
 
+#include <stdexcept>
+
 #include "flashlight/fl/dataset/FileBlobDataset.h"
 
 namespace fl {
 
 FileBlobDataset::FileBlobDataset(
-    const std::string& name,
+    const fs::path& name,
     bool rw,
     bool truncate)
     : name_(name) {
   mode_ = (rw ? std::ios_base::in | std::ios_base::out : std::ios_base::in);
   {
     std::ofstream fs(name_, (truncate ? mode_ | std::ios_base::trunc : mode_));
     if (!fs.is_open()) {
-      throw std::runtime_error("could not open file " + name);
+      throw std::runtime_error("could not open file " + name.string());
     }
   }
   readIndex();

flashlight/fl/dataset/FileBlobDataset.h

@@ -7,6 +7,7 @@
 
 #pragma once
 
+#include "flashlight/fl/common/Filesystem.h"
 #include "flashlight/fl/dataset/BlobDataset.h"
 
 #include <fstream>
@@ -33,7 +34,7 @@ class FileBlobDataset : public BlobDataset {
    * already exists.
    */
   explicit FileBlobDataset(
-      const std::string& name,
+      const fs::path& name,
       bool rw = false,
       bool truncate = false);
 
@@ -47,7 +48,7 @@ class FileBlobDataset : public BlobDataset {
   bool isEmptyData() const override;
 
  private:
-  std::string name_;
+  fs::path name_;
   std::ios_base::openmode mode_;
   std::shared_ptr<std::fstream> getStream() const;
 

flashlight/fl/dataset/ShuffleDataset.cpp

@@ -8,6 +8,7 @@
 #include "flashlight/fl/dataset/ShuffleDataset.h"
 
 #include <algorithm>
+#include <numeric>
 
 namespace fl {
 

flashlight/fl/examples/RnnLm.cpp

@@ -168,7 +168,7 @@ int main(int argc, char** argv) {
 
   SGDOptimizer opt(model.params(), learning_rate);
 
-  auto eval_loop = [&model, &criterion](LMDataset& dataset) {
+  auto eval_loop = [&model, &criterion, kInputIdx, kTargetIdx](LMDataset& dataset) {
     AverageValueMeter avg_loss_meter;
     Variable output, h, c;
     for (auto& example : dataset) {

flashlight/fl/tensor/Index.h

@@ -8,6 +8,7 @@
 #pragma once
 
 #include <variant>
+#include <optional>
 
 #include "flashlight/fl/tensor/TensorBase.h"
 

flashlight/fl/tensor/Init.cpp

@@ -7,9 +7,6 @@
 
 #include <mutex>
 
-#include <iostream>
-#include <string>
-
 #include "flashlight/fl/tensor/DefaultTensorType.h"
 #include "flashlight/fl/tensor/TensorBackend.h"
 

flashlight/fl/tensor/TensorBase.cpp

@@ -9,6 +9,7 @@
 
 #include <stdexcept>
 #include <utility>
+#include <algorithm>
 
 #include "flashlight/fl/tensor/DefaultTensorType.h"
 #include "flashlight/fl/tensor/TensorAdapter.h"

flashlight/fl/tensor/backend/af/ArrayFireReductions.cpp

@@ -7,6 +7,8 @@
 
 #include "flashlight/fl/tensor/backend/af/ArrayFireBackend.h"
 
+#include <algorithm>
+
 #include <af/arith.h>
 #include <af/gfor.h>
 

flashlight/fl/tensor/backend/jit/opt/backends/onednn/OneDnnOpFusion.cpp

@@ -23,6 +23,8 @@ struct BinopInfo {
 };
 
 struct OneDnnOpFusion::SearchState {
+  SearchState(Node* root, std::vector<BinopInfo> binopInfos)
+      : searchRoot(root), accumulatedBinopInfos(binopInfos) {}
   Node* searchRoot;
   // Assume `searchRoot == binop2`
   //
@@ -94,7 +96,7 @@ bool shouldNodeBeFused(const Node* node) {
 } // namespace
 
 Node* OneDnnOpFusion::rewriteFrom(Node* node) {
-  SearchState state{.searchRoot = node, .accumulatedBinopInfos = {}};
+  SearchState state(node, /* accumulatedBinopInfos = */ {});
   auto fusedNode = searchAndFuse(node, state);
   node->replaceAllUsesWith(fusedNode);
   return fusedNode;