[runtime] [proxy] Implementing [[Call]]

src/x87/builtins-x87.cc

Index: src/x87/builtins-x87.cc
diff --git a/src/x87/builtins-x87.cc b/src/x87/builtins-x87.cc
index 130b61660c82ff91b9cb2b379d5e99aa54b9466c..4418d87a611c5ecff8072f2085be5e5f11ff9f48 100644
--- a/src/x87/builtins-x87.cc
+++ b/src/x87/builtins-x87.cc
@@ -1542,8 +1542,16 @@ void Builtins::Generate_Call(MacroAssembler* masm, ConvertReceiverMode mode) {
   __ CmpInstanceType(ecx, JS_PROXY_TYPE);
   __ j(not_equal, &non_function);
 
-  // 1. Call to function proxy.
-  // TODO(neis): Implement [[Call]] on proxies.
+  // 1. Runtime fallback for Proxy [[Call]].
+  __ PopReturnAddressTo(ecx);
+  __ Push(edi);
+  __ PushReturnAddressFrom(ecx);
+  // Increase the arguments size to include the pushed function and the
+  // existing receiver on the stack.
+  __ addp(eax, Immediate(2));
+  // Tail-call to the runtime.
+  __ JumpToExternalReference(
+      ExternalReference(Runtime::kJSProxyCall, masm->isolate()));
 
   // 2. Call to something else, which might have a [[Call]] internal method (if
   // not we raise an exception).