Introduce flag --allocation-site-transitioning

src/hydrogen.cc

 // Copyright 2013 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/hydrogen.h"
 
 #include <algorithm>
 #include <sstream>
 
 #include "src/v8.h"
@@ skipping 8977 matching lines @@
   return true;
 }
 
 
 bool HOptimizedGraphBuilder::TryHandleArrayCallNew(CallNew* expr,
                                                    HValue* function) {
   if (!array_function().is_identical_to(expr->target())) {
     return false;
   }
 
+  // Special handling for array construction only makes sense if we are
+  // using allocation sites.
+  if (!FLAG_allocation_site_transitioning) {
+    return false;
+  }
+
   BuildArrayCall(expr,
                  expr->arguments()->length(),
                  function,
                  expr->allocation_site());
   return true;
 }
 
 
 void HOptimizedGraphBuilder::VisitCall(Call* expr) {
   DCHECK(!HasStackOverflow());
@@ skipping 230 matching lines @@
 }
 
 
 bool HOptimizedGraphBuilder::IsCallArrayInlineable(
     int argument_count,
     Handle<AllocationSite> site) {
   Handle<JSFunction> caller = current_info()->closure();
   Handle<JSFunction> target = array_function();
   // We should have the function plus array arguments on the environment stack.
   DCHECK(environment()->length() >= (argument_count + 1));
-  DCHECK(!site.is_null());
 
   bool inline_ok = false;
-  if (site->CanInlineCall()) {
+  if (!site.is_null() && site->CanInlineCall()) {
     // We also want to avoid inlining in certain 1 argument scenarios.
     if (argument_count == 1) {
       HValue* argument = Top();
       if (argument->IsConstant()) {
         // Do not inline if the constant length argument is not a smi or
         // outside the valid range for unrolled loop initialization.
         HConstant* constant_argument = HConstant::cast(argument);
         if (constant_argument->HasSmiValue()) {
           int value = constant_argument->Integer32Value();
           inline_ok = value >= 0 && value <= kElementLoopUnrollThreshold;
@@ skipping 3279 matching lines @@
   if (ShouldProduceTraceOutput()) {
     isolate()->GetHTracer()->TraceHydrogen(name(), graph_);
   }
 
 #ifdef DEBUG
   graph_->Verify(false);  // No full verify.
 #endif
 }
 
 } }  // namespace v8::internal