- Remove arguments definition test from the VM.

runtime/vm/flow_graph_compiler_x64.cc

 // Copyright (c) 2013, 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 1095 matching lines @@
   const Function& function = parsed_function().function();
 
   const int num_fixed_params = function.num_fixed_parameters();
   const int num_copied_params = parsed_function().num_copied_params();
   const int num_locals = parsed_function().num_stack_locals();
 
   // We check the number of passed arguments when we have to copy them due to
   // the presence of optional parameters.
   // No such checking code is generated if only fixed parameters are declared,
   // unless we are in debug mode or unless we are compiling a closure.
-  LocalVariable* saved_args_desc_var =
-      parsed_function().GetSavedArgumentsDescriptorVar();
   if (num_copied_params == 0) {
 #ifdef DEBUG
     ASSERT(!parsed_function().function().HasOptionalParameters());
     const bool check_arguments = !flow_graph().IsCompiledForOsr();
 #else
     const bool check_arguments =
         (function.IsClosureFunction() || function.IsNoSuchMethodDispatcher()) &&
         !flow_graph().IsCompiledForOsr();
 #endif
     if (check_arguments) {
@@ skipping 23 matching lines @@
         __ LoadObject(RBX, ic_data);
         __ LeaveFrame();  // The arguments are still on the stack.
         __ jmp(&StubCode::CallNoSuchMethodFunctionLabel());
         // The noSuchMethod call may return to the caller, but not here.
         __ int3();
       } else {
         __ Stop("Wrong number of arguments");
       }
       __ Bind(&correct_num_arguments);
     }
-    // The arguments descriptor is never saved in the absence of optional
-    // parameters, since any argument definition test would always yield true.
-    ASSERT(saved_args_desc_var == NULL);
   } else if (!flow_graph().IsCompiledForOsr()) {
-    if (saved_args_desc_var != NULL) {
-      __ Comment("Save arguments descriptor");
-      const Register kArgumentsDescriptorReg = R10;
-      // The saved_args_desc_var is allocated one slot before the first local.
-      const intptr_t slot = parsed_function().first_stack_local_index() + 1;
-      // If the saved_args_desc_var is captured, it is first moved to the stack
-      // and later to the context, once the context is allocated.
-      ASSERT(saved_args_desc_var->is_captured() ||
-             (saved_args_desc_var->index() == slot));
-      __ movq(Address(RBP, slot * kWordSize), kArgumentsDescriptorReg);
-    }
     CopyParameters();
   }
 
   // In unoptimized code, initialize (non-argument) stack allocated slots to
-  // null. This does not cover the saved_args_desc_var slot.
+  // null.
   if (!is_optimizing() && (num_locals > 0)) {
     __ Comment("Initialize spill slots");
     const intptr_t slot_base = parsed_function().first_stack_local_index();
     const Immediate& raw_null =
         Immediate(reinterpret_cast<intptr_t>(Object::null()));
     __ movq(RAX, raw_null);
     for (intptr_t i = 0; i < num_locals; ++i) {
       // Subtract index i (locals lie at lower addresses than RBP).
       __ movq(Address(RBP, (slot_base - i) * kWordSize), RAX);
     }
@@ skipping 696 matching lines @@
   __ movups(reg, Address(RSP, 0));
   __ addq(RSP, Immediate(kFpuRegisterSize));
 }
 
 
 #undef __
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_X64