AllocationSites for all literals

src/allocation-site-scopes.cc

+// Copyright 2013 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
+//       with the distribution.
+//     * Neither the name of Google Inc. nor the names of its
+//       contributors may be used to endorse or promote products derived
+//       from this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+#include "allocation-site-scopes.h"
+
+namespace v8 {
+namespace internal {
+
+
+AllocationSiteCreationScope::AllocationSiteCreationScope(
+    AllocationSiteContext* context) {
+  site_context_ = context;
+
+  if (context->top().is_null()) {
+    // We are creating the top level AllocationSite as opposed to a nested
+    // AllocationSite.
+    context->top_ = context->isolate_->factory()->NewAllocationSite();
+    ASSERT(!(context->top_->IsFailure()));
+    context->current_ = Handle<AllocationSite>(*(context->top()),
+                                               context->isolate_);
+    current_ = Handle<AllocationSite>(*(context->top()), context->isolate_);
+    if (FLAG_trace_creation_allocation_sites) {
+      PrintF("*** Creating top level AllocationSite %p\n",
+             static_cast<void*>(*current_));
+    }
+  } else if (context->activated()) {
+    ASSERT(!context->current().is_null());
+    Handle<AllocationSite> new_site =
+        context->isolate_->factory()->NewAllocationSite();
+    ASSERT(!new_site->IsFailure());
+    if (FLAG_trace_creation_allocation_sites) {
+      PrintF("Creating nested site (top, current, new) (%p, %p, %p)\n",
+             static_cast<void*>(*(context->top())),
+             static_cast<void*>(*(context->current())),
+             static_cast<void*>(*new_site));
+    }
+    context->current()->set_nested_site(*new_site);
+    context->set_current(*new_site);
+    current_ = Handle<AllocationSite>(*new_site, context->isolate_);
+  }
+}
+
+
+Handle<Object> AllocationSiteCreationScope::RecordTransitionInfo(
+    Handle<Object> transition_info) {
+  if (!transition_info.is_null() && !transition_info->IsFailure()) {
+    bool top_level = !current_.is_null() &&
+        site_context_->top().is_identical_to(current_);
+
+    if (top_level || site_context_->activated()) {
+      current_->set_transition_info(*transition_info);
+      if (FLAG_trace_creation_allocation_sites) {
+        if (top_level) {
+          PrintF("*** Setting AllocationSite %p transition_info %p\n",
+                 static_cast<void*>(*current_),
+                 static_cast<void*>(*transition_info));
+        } else {
+          PrintF("Setting AllocationSite (%p, %p) transition_info %p\n",
+                 static_cast<void*>(*(site_context_->top())),
+                 static_cast<void*>(*current_),
+                 static_cast<void*>(*transition_info));
+        }
+      }
+    }
+  }
+  return transition_info;
+}
+
+
+AllocationSiteUsageScope::AllocationSiteUsageScope(
+    AllocationSiteContext* context,
+    Handle<Object> expected_transition_info) {
+  ASSERT(!context->top().is_null());
+
+  // Advance current site if activated.
+  if (context->activated()) {
+    Object* nested_site = context->current_->nested_site();
+    // Something is wrong if we advance to the end of the list here.
+    ASSERT(nested_site->IsAllocationSite());
+    AllocationSite* casted_site = AllocationSite::cast(nested_site);
+    context->set_current(casted_site);
+
+    // This assert ensures that we are pointing at the right sub-object
+    // in a recursive walk of a nested literal. It's the only
+    // usage of parameter expected_transition_info.
+    ASSERT(*expected_transition_info == casted_site->transition_info());
+  }
+}
+
+
+AllocationSiteUsageScope::AllocationSiteUsageScope(
+    AllocationSiteContext* context,
+    Handle<AllocationSite> top,
+    Handle<Object> expected_transition_info) {
+  ASSERT(context->top().is_null());
+  context->top_ = top;
+  if (context->activated()) {
+    // We only need current_ to be a handle if we are using the field.
+    // We only use the field in the recursive case.
+    context->current_ = Handle<AllocationSite>(*top, context->isolate_);
+  }
+
+  // This assert ensures that we are pointing at the right object in the
+  // allocation site during a recursive walk of a nested literal. It's the only
+  // usage of parameter expected_transition_info.
+  ASSERT(*expected_transition_info == top->transition_info());
+}
+
+} }  // namespace v8::internal