Remove --check-stack flag from V8.

src/x64/codegen-x64.cc

 // Copyright 2009 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 834 matching lines @@
 };
 
 
 void DeferredStackCheck::Generate() {
   StackCheckStub stub;
   __ CallStub(&stub);
 }
 
 
 void CodeGenerator::CheckStack() {
-  if (FLAG_check_stack) {
-    DeferredStackCheck* deferred = new DeferredStackCheck;
-    __ CompareRoot(rsp, Heap::kStackLimitRootIndex);
-    deferred->Branch(below);
-    deferred->BindExit();
-  }
+  DeferredStackCheck* deferred = new DeferredStackCheck;
+  __ CompareRoot(rsp, Heap::kStackLimitRootIndex);
+  deferred->Branch(below);
+  deferred->BindExit();
 }
 
 
 void CodeGenerator::VisitAndSpill(Statement* statement) {
   // TODO(X64): No architecture specific code. Move to shared location.
   ASSERT(in_spilled_code());
   set_in_spilled_code(false);
   Visit(statement);
   if (frame_ != NULL) {
     frame_->SpillAll();
@@ skipping 7004 matching lines @@
   masm.GetCode(&desc);
   // Call the function from C++.
   return FUNCTION_CAST<ModuloFunction>(buffer);
 }
 
 #endif
 
 #undef __
 
 } }  // namespace v8::internal