Bind the new *_unchecked function APIs (#17)

This commit binds two new APIs added to `wasmtime`'s C API recently:

* `wasmtime_func_new_unchecked`
* `wamstime_func_call_unchecked`

These two functions are a more accelerated path of invoking a
WebAssembly function and having a WebAssembly function call the host.
The new APIs are generally unsafe but with the C++ bindings added here
they should at least be type-safe. The goal was to add APIs similar to
the Rust crate's `Func::wrap` and `Func::typed` for statically-typed
function calls.

Overall the performance here worked out great in that it's on-par with C
and as expected from the PR adding the `*_unchecked` variants. This is,
however, basically my first foray into templated functions in C++ and
wow is this a lot more complicated than I thought that it would be. Some
extra eyes on this would be appreciated to see if I've missed something
or if the design could be simplified.

Author: alexcrichton

.github/workflows/main.yml

@@ -25,8 +25,8 @@ jobs:
     steps:
     - uses: actions/checkout@v2
     - run: sudo apt-get update -y && sudo apt-get install -y libclang1-9 libclang-cpp9
-    - run: curl -L https://doxygen.nl/files/doxygen-1.9.1.linux.bin.tar.gz | tar xzf -
-    - run: echo "`pwd`/doxygen-1.9.1/bin" >> $GITHUB_PATH
+    - run: curl -L https://doxygen.nl/files/doxygen-1.9.2.linux.bin.tar.gz | tar xzf -
+    - run: echo "`pwd`/doxygen-1.9.2/bin" >> $GITHUB_PATH
     - run: doxygen doxygen.conf
     - run: tar czf html.tar.gz html
     - uses: actions/upload-artifact@v2

CMakeLists.txt

@@ -14,6 +14,12 @@ set(CMAKE_CXX_STANDARD_REQUIRED True)
 option(ENABLE_CODE_ANALYSIS "Run code analysis" OFF)
 message(STATUS "ENABLE_CODE_ANALYSIS       ${ENABLE_CODE_ANALYSIS}")
 
+if ("${CMAKE_CXX_COMPILER_ID}" STREQUAL "GNU")
+   add_compile_options (-fdiagnostics-color=always)
+elseif ("${CMAKE_CXX_COMPILER_ID}" STREQUAL "Clang")
+   add_compile_options (-fcolor-diagnostics)
+endif ()
+
 add_library(wasmtime-cpp INTERFACE ${CMAKE_SOURCE_DIR}/include/wasmtime.hh)
 target_link_libraries(wasmtime-cpp INTERFACE wasmtime)
 if (MSVC)

doxygen.conf

@@ -810,7 +810,7 @@ WARNINGS               = YES
 # will automatically be disabled.
 # The default value is: YES.
 
-WARN_IF_UNDOCUMENTED   = YES
+WARN_IF_UNDOCUMENTED   = NO
 
 # If the WARN_IF_DOC_ERROR tag is set to YES, doxygen will generate warnings for
 # potential errors in the documentation, such as not documenting some parameters
@@ -1886,7 +1886,7 @@ PDF_HYPERLINKS         = YES
 # The default value is: YES.
 # This tag requires that the tag GENERATE_LATEX is set to YES.
 
-USE_PDFLATEX           = YES
+USE_PDFLATEX           = NO
 
 # If the LATEX_BATCHMODE tag is set to YES, doxygen will add the \batchmode
 # command to the generated LaTeX files. This will instruct LaTeX to keep running

examples/hello.cc

@@ -31,16 +31,10 @@ int main() {
 
   // Our wasm module we'll be instantiating requires one imported function.
   // the function takes no parameters and returns no results. We create a host
-  // implementation of that function here, and the `caller` parameter here is
-  // used to get access to our original `MyState` value.
+  // implementation of that function here.
   std::cout << "Creating callback...\n";
-  FuncType ty({}, {});
-  Func host_func(store, ty, [](auto caller, auto args, auto results) -> auto {
+  Func host_func = Func::wrap(store, []() {
       std::cout << "Calling back...\n";
-      (void) caller;
-      (void) args;
-      (void) results;
-      return std::monostate();
   });
 
   // Once we've got that all set up we can then move to the instantiation