Proposing user-defined inlining

src/binaryen-c.cpp

@@ -2685,6 +2685,22 @@ void BinaryenFunctionSetDebugLocation(BinaryenFunctionRef func, BinaryenExpressi
 
   fn->debugLocations[ex] = loc;
 }
+int BinaryenFunctionGetUserFlags(BinaryenFunctionRef func) {
+  if (tracing) {
+    std::cout << "  BinaryenFunctionGetUserFlags(functions[" << functions[func] << "]);\n";
+  }
+
+  auto* fn = (Function*)func;
+  return static_cast<int>(fn->userFlags);
+}
+void BinaryenFunctionSetUserFlags(BinaryenFunctionRef func, int flags) {
+  if (tracing) {
+    std::cout << "  BinaryenFunctionSetUserFlags(functions[" << functions[func] << "], " << flags << ");\n";
+  }
+
+  auto* fn = (Function*)func;
+  fn->userFlags = (Function::UserFlags)flags;
+}
 
 //
 // =========== Import operations ===========

src/binaryen-c.h

@@ -869,6 +869,11 @@ void BinaryenFunctionRunPasses(BinaryenFunctionRef func, BinaryenModuleRef modul
 // Sets the debug location of the specified `Expression` within the specified `Function`.
 void BinaryenFunctionSetDebugLocation(BinaryenFunctionRef func, BinaryenExpressionRef expr, BinaryenIndex fileIndex, BinaryenIndex lineNumber, BinaryenIndex columnNumber);
 
+// Gets the user defined flags for this function
+int BinaryenFunctionGetUserFlags(BinaryenFunctionRef func);
+// Sets the user defined flags for this function
+void BinaryenFunctionSetUserFlags(BinaryenFunctionRef func, int flags);
+
 //
 // ========== Import Operations ==========
 //

src/passes/Inlining.cpp

@@ -284,7 +284,7 @@ struct Inlining : public Pass {
     // decide which to inline
     InliningState state;
     ModuleUtils::iterDefinedFunctions(*module, [&](Function* func) {
-      if (infos[func->name].worthInlining(runner->options)) {
+      if (func->hasUserFlags(Function::UserFlags::Inline) || infos[func->name].worthInlining(runner->options)) {
         state.worthInlining.insert(func->name);
       }
     });

src/wasm.h

@@ -781,6 +781,17 @@ class Function : public Importable {
 
   void clearNames();
   void clearDebugInfo();
+
+  // Special flags that can be set by a an API user
+  enum class UserFlags : unsigned int {
+    None = 0,
+    Inline = 1 << 0
+  };
+  UserFlags userFlags = UserFlags::None;
+
+  bool hasUserFlags(UserFlags flags) {
+    return static_cast<UserFlags>((static_cast<int>(userFlags) & static_cast<int>(flags))) == flags;
+  }
 };
 
 // The kind of an import or export.