DRAFT: Add logging option

site/source/docs/porting/connecting_cpp_and_javascript/embind.rst

@@ -1074,6 +1074,16 @@ registered using :cpp:func:`EMSCRIPTEN_DECLARE_VAL_TYPE` in combination with
         register_type<CallbackType>("(message: string) => void");
     }
 
+Embind Debugging
+======================
+
+TO help you debug, you can use enable `-sEMBIND_DEBUG` which log every wasm call.
+To use it, invoke *emcc* with the `-sEMBIND_DEBUG` option
+
+emcc -lembind quick_example.cpp -sEMBIND_DEBUG example.js
+
+Running this command will build the program with an js call every time you call the wasm.
+
 Performance
 ===========
 

src/embind/embind.js

@@ -830,6 +830,13 @@ var LibraryEmbind = {
       if (arguments.length !== expectedArgCount) {
         throwBindingError(`function ${humanName} called with ${arguments.length} arguments, expected ${expectedArgCount}`);
       }
+#if EMBIND_DEBUG
+      if (Object.values(arguments).length > 0){
+          dbg('${humanName}(' + Object.values(arguments).join(',') + ')');
+      } else {
+          dbg('${humanName}()');
+      }
+#endif
 #if EMSCRIPTEN_TRACING
       Module.emscripten_trace_enter_context(`embind::${humanName}`);
 #endif

src/settings.js

@@ -351,6 +351,10 @@ var DEMANGLE_SUPPORT = false;
 // [link]
 var LIBRARY_DEBUG = false;
 
+// If nonzero, prints out each call to WebAssembly with arguments
+// [compile+link]
+var EMBIND_DEBUG = false;
+
 // Print out all musl syscalls, including translating their numeric index
 // to the string name, which can be convenient for debugging. (Other system
 // calls are not numbered and already have clear names; use LIBRARY_DEBUG

tools/link.py

@@ -682,6 +682,7 @@ def phase_linker_setup(options, state, newargs):
 
   if not settings.RUNTIME_DEBUG:
     settings.RUNTIME_DEBUG = bool(settings.LIBRARY_DEBUG or
+                                  settings.EMBIND_DEBUG or
                                   settings.GL_DEBUG or
                                   settings.DYLINK_DEBUG or
                                   settings.OPENAL_DEBUG or