| /* |
| * Copyright (c) 2014, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| * |
| */ |
| |
| #ifndef SHARE_VM_OPTO_REPLACEDNODES_HPP |
| #define SHARE_VM_OPTO_REPLACEDNODES_HPP |
| |
| #include "opto/connode.hpp" |
| |
| // During parsing, when a node is "improved", |
| // GraphKit::replace_in_map() is called to update the current map so |
| // that the improved node is used from that point |
| // on. GraphKit::replace_in_map() doesn't operate on the callers maps |
| // and so some optimization opportunities may be lost. The |
| // ReplacedNodes class addresses that problem. |
| // |
| // A ReplacedNodes object is a list of pair of nodes. Every |
| // SafePointNode carries a ReplacedNodes object. Every time |
| // GraphKit::replace_in_map() is called, a new pair of nodes is pushed |
| // on the list of replaced nodes. When control flow paths merge, their |
| // replaced nodes are also merged. When parsing exits a method to |
| // return to a caller, the replaced nodes on the exit path are used to |
| // update the caller's map. |
| class ReplacedNodes VALUE_OBJ_CLASS_SPEC { |
| private: |
| class ReplacedNode VALUE_OBJ_CLASS_SPEC { |
| private: |
| Node* _initial; |
| Node* _improved; |
| public: |
| ReplacedNode() : _initial(NULL), _improved(NULL) {} |
| ReplacedNode(Node* initial, Node* improved) : _initial(initial), _improved(improved) {} |
| Node* initial() const { return _initial; } |
| Node* improved() const { return _improved; } |
| |
| bool operator==(const ReplacedNode& other) { |
| return _initial == other._initial && _improved == other._improved; |
| } |
| }; |
| GrowableArray<ReplacedNode>* _replaced_nodes; |
| |
| void allocate_if_necessary(); |
| bool has_node(const ReplacedNode& r) const; |
| bool has_target_node(Node* n) const; |
| |
| public: |
| ReplacedNodes() |
| : _replaced_nodes(NULL) {} |
| |
| void clone(); |
| void record(Node* initial, Node* improved); |
| void transfer_from(const ReplacedNodes& other, uint idx); |
| void reset(); |
| void apply(Node* n, uint idx); |
| void merge_with(const ReplacedNodes& other); |
| bool is_empty() const; |
| void dump(outputStream *st) const; |
| void apply(Compile* C, Node* ctl); |
| }; |
| |
| #endif // SHARE_VM_OPTO_REPLACEDNODES_HPP |