| /** |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, |
| * software distributed under the License is distributed on an |
| * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| * KIND, either express or implied. See the License for the |
| * specific language governing permissions and limitations |
| * under the License. |
| */ |
| #pragma once |
| |
| #if ENABLE(DFG_JIT) |
| |
| #include "DFGFlushedAt.h" |
| #include "DFGVariableAccessData.h" |
| |
| namespace JSC { namespace DFG { |
| |
| struct Node; |
| |
| class Availability { |
| public: |
| Availability() |
| : m_node(0) |
| , m_flushedAt(DeadFlush) |
| { |
| } |
| |
| explicit Availability(Node* node) |
| : m_node(node) |
| , m_flushedAt(ConflictingFlush) |
| { |
| } |
| |
| explicit Availability(FlushedAt flushedAt) |
| : m_node(unavailableMarker()) |
| , m_flushedAt(flushedAt) |
| { |
| } |
| |
| Availability(Node* node, FlushedAt flushedAt) |
| : m_node(node) |
| , m_flushedAt(flushedAt) |
| { |
| } |
| |
| static Availability unavailable() |
| { |
| return Availability(unavailableMarker(), FlushedAt(ConflictingFlush)); |
| } |
| |
| Availability withFlush(FlushedAt flush) const |
| { |
| return Availability(m_node, flush); |
| } |
| |
| Availability withNode(Node* node) const |
| { |
| return Availability(node, m_flushedAt); |
| } |
| |
| Availability withUnavailableNode() const |
| { |
| return withNode(unavailableMarker()); |
| } |
| |
| void setFlush(FlushedAt flushedAt) |
| { |
| m_flushedAt = flushedAt; |
| } |
| |
| void setNode(Node* node) |
| { |
| m_node = node; |
| } |
| |
| void setNodeUnavailable() |
| { |
| m_node = unavailableMarker(); |
| } |
| |
| bool nodeIsUndecided() const { return !m_node; } |
| bool nodeIsUnavailable() const { return m_node == unavailableMarker(); } |
| |
| bool hasNode() const { return !nodeIsUndecided() && !nodeIsUnavailable(); } |
| bool shouldUseNode() const { return !isFlushUseful() && hasNode(); } |
| |
| Node* node() const |
| { |
| ASSERT(!nodeIsUndecided()); |
| ASSERT(!nodeIsUnavailable()); |
| return m_node; |
| } |
| |
| FlushedAt flushedAt() const { return m_flushedAt; } |
| bool isFlushUseful() const |
| { |
| return flushedAt().format() != DeadFlush && flushedAt().format() != ConflictingFlush; |
| } |
| |
| bool isDead() const { return !isFlushUseful() && !hasNode(); } |
| |
| bool operator!() const { return nodeIsUnavailable() && flushedAt().format() == ConflictingFlush; } |
| |
| bool operator==(const Availability& other) const |
| { |
| return m_node == other.m_node |
| && m_flushedAt == other.m_flushedAt; |
| } |
| |
| bool operator!=(const Availability& other) const |
| { |
| return !(*this == other); |
| } |
| |
| Availability merge(const Availability& other) const |
| { |
| return Availability( |
| mergeNodes(m_node, other.m_node), |
| m_flushedAt.merge(other.m_flushedAt)); |
| } |
| |
| void dump(PrintStream&) const; |
| void dumpInContext(PrintStream&, DumpContext*) const; |
| |
| private: |
| static Node* mergeNodes(Node* a, Node* b) |
| { |
| if (!a) |
| return b; |
| if (!b) |
| return a; |
| if (a == b) |
| return a; |
| return unavailableMarker(); |
| } |
| |
| static Node* unavailableMarker() |
| { |
| return bitwise_cast<Node*>(static_cast<intptr_t>(1)); |
| } |
| |
| Node* m_node; |
| FlushedAt m_flushedAt; |
| }; |
| |
| } } // namespace JSC::DFG |
| |
| #endif // ENABLE(DFG_JIT) |