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1 // Copyright 2013 the V8 project authors. All rights reserved.
2 // Redistribution and use in source and binary forms, with or without
3 // modification, are permitted provided that the following conditions are
4 // met:
5 //
6 //     * Redistributions of source code must retain the above copyright
7 //       notice, this list of conditions and the following disclaimer.
8 //     * Redistributions in binary form must reproduce the above
9 //       copyright notice, this list of conditions and the following
10 //       disclaimer in the documentation and/or other materials provided
11 //       with the distribution.
12 //     * Neither the name of Google Inc. nor the names of its
13 //       contributors may be used to endorse or promote products derived
14 //       from this software without specific prior written permission.
15 //
16 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
17 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
18 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
19 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
20 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
21 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
22 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
26 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 
28 #include "allocation-site-scopes.h"
29 
30 namespace v8 {
31 namespace internal {
32 
33 
EnterNewScope()34 Handle<AllocationSite> AllocationSiteCreationContext::EnterNewScope() {
35   Handle<AllocationSite> scope_site;
36   if (top().is_null()) {
37     // We are creating the top level AllocationSite as opposed to a nested
38     // AllocationSite.
39     InitializeTraversal(isolate()->factory()->NewAllocationSite());
40     scope_site = Handle<AllocationSite>(*top(), isolate());
41     if (FLAG_trace_creation_allocation_sites) {
42       PrintF("*** Creating top level AllocationSite %p\n",
43              static_cast<void*>(*scope_site));
44     }
45   } else {
46     ASSERT(!current().is_null());
47     scope_site = isolate()->factory()->NewAllocationSite();
48     if (FLAG_trace_creation_allocation_sites) {
49       PrintF("Creating nested site (top, current, new) (%p, %p, %p)\n",
50              static_cast<void*>(*top()),
51              static_cast<void*>(*current()),
52              static_cast<void*>(*scope_site));
53     }
54     current()->set_nested_site(*scope_site);
55     update_current_site(*scope_site);
56   }
57   ASSERT(!scope_site.is_null());
58   return scope_site;
59 }
60 
61 
ExitScope(Handle<AllocationSite> scope_site,Handle<JSObject> object)62 void AllocationSiteCreationContext::ExitScope(
63     Handle<AllocationSite> scope_site,
64     Handle<JSObject> object) {
65   if (!object.is_null() && !object->IsFailure()) {
66     bool top_level = !scope_site.is_null() &&
67         top().is_identical_to(scope_site);
68 
69     scope_site->set_transition_info(*object);
70     if (FLAG_trace_creation_allocation_sites) {
71       if (top_level) {
72         PrintF("*** Setting AllocationSite %p transition_info %p\n",
73                static_cast<void*>(*scope_site),
74                static_cast<void*>(*object));
75       } else {
76         PrintF("Setting AllocationSite (%p, %p) transition_info %p\n",
77                static_cast<void*>(*top()),
78                static_cast<void*>(*scope_site),
79                static_cast<void*>(*object));
80       }
81     }
82   }
83 }
84 
85 
ShouldCreateMemento(Handle<JSObject> object)86 bool AllocationSiteUsageContext::ShouldCreateMemento(Handle<JSObject> object) {
87   if (activated_ && AllocationSite::CanTrack(object->map()->instance_type())) {
88     if (FLAG_allocation_site_pretenuring ||
89         AllocationSite::GetMode(object->GetElementsKind()) ==
90         TRACK_ALLOCATION_SITE) {
91       if (FLAG_trace_creation_allocation_sites) {
92         PrintF("*** Creating Memento for %s %p\n",
93                object->IsJSArray() ? "JSArray" : "JSObject",
94                static_cast<void*>(*object));
95       }
96       return true;
97     }
98   }
99   return false;
100 }
101 
102 } }  // namespace v8::internal
103