forward assertions setting into backend, and use it to check for invalid # of args in static calls

2 files changed, 16 insertions, 0 deletions

diff --git a/lib/Target/JSBackend/CallHandlers.h b/lib/Target/JSBackend/CallHandlers.h
index 93275b9637..9ad89ee169 100644
--- a/lib/Target/JSBackend/CallHandlers.h
+++ b/lib/Target/JSBackend/CallHandlers.h
@@ -44,6 +44,17 @@ DEF_CALL_HANDLER(__default__, {
   if (F) {
     NeedCasts = F->isDeclaration(); // if ffi call, need casts
     FT = F->getFunctionType();
+    if (EmscriptenAssertions) {
+      unsigned TypeNumArgs = FT->getNumParams();
+      unsigned ActualNumArgs = getNumArgOperands(CI);
+      if (TypeNumArgs != ActualNumArgs) {
+        errs().changeColor(raw_ostream::YELLOW);
+        errs() << "warning:";
+        errs().resetColor();
+        errs() << " unexpected number of arguments " << utostr(ActualNumArgs) << " in call to '" << F->getName() << "', should be " << utostr(TypeNumArgs) << "\n";
+      }
+      // TODO: also check types of arguments, but must take into account JS types, not LLVM types
+    }
   } else {
     if (isAbsolute(CV)) return "abort(); /* segfault, call an absolute addr */";
     // function pointer call
diff --git a/lib/Target/JSBackend/JSBackend.cpp b/lib/Target/JSBackend/JSBackend.cpp
index b0a4b496ac..6ed2632441 100644
--- a/lib/Target/JSBackend/JSBackend.cpp
+++ b/lib/Target/JSBackend/JSBackend.cpp
@@ -76,6 +76,11 @@ ReservedFunctionPointers("emscripten-reserved-function-pointers",
                          cl::desc("Number of reserved slots in function tables for functions to be added at runtime (see emscripten RESERVED_FUNCTION_POINTERS option)"),
                          cl::init(0));
 
+static cl::opt<int>
+EmscriptenAssertions("emscripten-assertions",
+                     cl::desc("Additional JS-specific assertions (see emscripten ASSERTIONS)"),
+                     cl::init(0));
+
 extern "C" void LLVMInitializeJSBackendTarget() {
   // Register the target.
   RegisterTargetMachine<JSTargetMachine> X(TheJSBackendTarget);