v8/src/feedback-slots.h
2014-02-10 21:38:17 +00:00

111 lines
3.5 KiB
C++

// Copyright 2014 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.
#ifndef V8_FEEDBACK_SLOTS_H_
#define V8_FEEDBACK_SLOTS_H_
#include "v8.h"
#include "isolate.h"
namespace v8 {
namespace internal {
enum ComputablePhase {
DURING_PARSE,
AFTER_SCOPING
};
class FeedbackSlotInterface {
public:
static const int kInvalidFeedbackSlot = -1;
virtual ~FeedbackSlotInterface() {}
// When can we ask how many feedback slots are necessary?
virtual ComputablePhase GetComputablePhase() = 0;
virtual int ComputeFeedbackSlotCount(Isolate* isolate) = 0;
virtual void SetFirstFeedbackSlot(int slot) = 0;
};
class DeferredFeedbackSlotProcessor {
public:
DeferredFeedbackSlotProcessor()
: slot_nodes_(NULL),
slot_count_(0) { }
void add_slot_node(Zone* zone, FeedbackSlotInterface* slot) {
if (slot->GetComputablePhase() == DURING_PARSE) {
// No need to add to the list
int count = slot->ComputeFeedbackSlotCount(zone->isolate());
slot->SetFirstFeedbackSlot(slot_count_);
slot_count_ += count;
} else {
if (slot_nodes_ == NULL) {
slot_nodes_ = new(zone) ZoneList<FeedbackSlotInterface*>(10, zone);
}
slot_nodes_->Add(slot, zone);
}
}
void ProcessFeedbackSlots(Isolate* isolate) {
// Scope analysis must have been done.
if (slot_nodes_ == NULL) {
return;
}
int current_slot = slot_count_;
for (int i = 0; i < slot_nodes_->length(); i++) {
FeedbackSlotInterface* slot_interface = slot_nodes_->at(i);
int count = slot_interface->ComputeFeedbackSlotCount(isolate);
if (count > 0) {
slot_interface->SetFirstFeedbackSlot(current_slot);
current_slot += count;
}
}
slot_count_ = current_slot;
slot_nodes_->Clear();
}
int slot_count() {
ASSERT(slot_count_ >= 0);
return slot_count_;
}
private:
ZoneList<FeedbackSlotInterface*>* slot_nodes_;
int slot_count_;
};
} } // namespace v8::internal
#endif // V8_FEEDBACK_SLOTS_H_