Fix issue with stack layout assumption going wrong when a dart function has optional parameters and…

vm/flow_graph_compiler_x64.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/globals.h"  // Needed here to get TARGET_ARCH_X64.
 #if defined(TARGET_ARCH_X64)
 
 #include "vm/flow_graph_compiler.h"
 
 #include "lib/error.h"
@@ skipping 1410 matching lines @@
   delete[] opt_param;
   delete[] opt_param_position;
   // Check that RDI now points to the null terminator in the array descriptor.
   const Immediate raw_null =
       Immediate(reinterpret_cast<intptr_t>(Object::null()));
   Label all_arguments_processed;
   __ cmpq(Address(RDI, 0), raw_null);
   __ j(EQUAL, &all_arguments_processed, Assembler::kNearJump);
 
   __ Bind(&wrong_num_arguments);
+  if (StackSize() != 0) {
+    // We need to unwind the space we reserved for locals and copied parmeters.
+    // The NoSuchMethodFunction stub does not expect to see that area on the
+    // stack.
+    __ addq(RSP, Immediate(StackSize() * kWordSize));
+  }
   if (function.IsClosureFunction()) {
     GenerateCallRuntime(AstNode::kNoId,
                         0,
                         CatchClauseNode::kInvalidTryIndex,
                         kClosureArgumentMismatchRuntimeEntry);
   } else {
     // Invoke noSuchMethod function.
     const int kNumArgsChecked = 1;
     ICData& ic_data = ICData::ZoneHandle();
     ic_data = ICData::New(parsed_function_.function(),
@@ skipping 270 matching lines @@
   ASSERT(exception_handlers_list_ != NULL);
   const ExceptionHandlers& handlers = ExceptionHandlers::Handle(
       exception_handlers_list_->FinalizeExceptionHandlers(code.EntryPoint()));
   code.set_exception_handlers(handlers);
 }
 
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_X64