src/allocation-site-scopes.cc

// Copyright 2013 the V8 project authors. All rights reserved.
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#include "allocation-site-scopes.h"

namespace v8 {
namespace internal {


Handle<AllocationSite> AllocationSiteCreationContext::EnterNewScope() {
  Handle<AllocationSite> scope_site;
  if (top().is_null()) {
    // We are creating the top level AllocationSite as opposed to a nested
    // AllocationSite.
    InitializeTraversal(isolate()->factory()->NewAllocationSite());
    scope_site = Handle<AllocationSite>(*top(), isolate());
    if (FLAG_trace_creation_allocation_sites) {
      PrintF("*** Creating top level AllocationSite %p\n",
             static_cast<void*>(*scope_site));
    }
  } else {
    ASSERT(!current().is_null());
    scope_site = isolate()->factory()->NewAllocationSite();
    if (FLAG_trace_creation_allocation_sites) {
      PrintF("Creating nested site (top, current, new) (%p, %p, %p)\n",
             static_cast<void*>(*top()),
             static_cast<void*>(*current()),
             static_cast<void*>(*scope_site));
    }
    current()->set_nested_site(*scope_site);
    update_current_site(*scope_site);
  }
  ASSERT(!scope_site.is_null());
  return scope_site;
}


void AllocationSiteCreationContext::ExitScope(
    Handle<AllocationSite> scope_site,
    Handle<JSObject> object) {
  if (!object.is_null() && !object->IsFailure()) {
    bool top_level = !scope_site.is_null() &&
        top().is_identical_to(scope_site);

    scope_site->set_transition_info(*object);
    if (FLAG_trace_creation_allocation_sites) {
      if (top_level) {
        PrintF("*** Setting AllocationSite %p transition_info %p\n",
               static_cast<void*>(*scope_site),
               static_cast<void*>(*object));
      } else {
        PrintF("Setting AllocationSite (%p, %p) transition_info %p\n",
               static_cast<void*>(*top()),
               static_cast<void*>(*scope_site),
               static_cast<void*>(*object));
      }
    }
  }
}


Handle<AllocationSite> AllocationSiteUsageContext::EnterNewScope() {
  if (top().is_null()) {
    InitializeTraversal(top_site_);
  } else {
    // Advance current site
    Object* nested_site = current()->nested_site();
    // Something is wrong if we advance to the end of the list here.
    ASSERT(nested_site->IsAllocationSite());
    update_current_site(AllocationSite::cast(nested_site));
  }
  return Handle<AllocationSite>(*current(), isolate());
}


void AllocationSiteUsageContext::ExitScope(
    Handle<AllocationSite> scope_site,
    Handle<JSObject> object) {
  // This assert ensures that we are pointing at the right sub-object in a
  // recursive walk of a nested literal.
  ASSERT(object.is_null() || *object == scope_site->transition_info());
}

} }  // namespace v8::internal