| /* |
| * Copyright (c) 2016, 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. |
| * |
| */ |
| |
| #include "precompiled.hpp" |
| #include "memory/resourceArea.hpp" |
| #include "opto/cfgnode.hpp" |
| #include "opto/phaseX.hpp" |
| #include "opto/replacednodes.hpp" |
| |
| void ReplacedNodes::allocate_if_necessary() { |
| if (_replaced_nodes == NULL) { |
| _replaced_nodes = new GrowableArray<ReplacedNode>(); |
| } |
| } |
| |
| bool ReplacedNodes::is_empty() const { |
| return _replaced_nodes == NULL || _replaced_nodes->length() == 0; |
| } |
| |
| bool ReplacedNodes::has_node(const ReplacedNode& r) const { |
| return _replaced_nodes->find(r) != -1; |
| } |
| |
| bool ReplacedNodes::has_target_node(Node* n) const { |
| for (int i = 0; i < _replaced_nodes->length(); i++) { |
| if (_replaced_nodes->at(i).improved() == n) { |
| return true; |
| } |
| } |
| return false; |
| } |
| |
| // Record replaced node if not seen before |
| void ReplacedNodes::record(Node* initial, Node* improved) { |
| allocate_if_necessary(); |
| ReplacedNode r(initial, improved); |
| if (!has_node(r)) { |
| _replaced_nodes->push(r); |
| } |
| } |
| |
| // Copy replaced nodes from one map to another. idx is used to |
| // identify nodes that are too new to be of interest in the target |
| // node list. |
| void ReplacedNodes::transfer_from(const ReplacedNodes& other, uint idx) { |
| if (other.is_empty()) { |
| return; |
| } |
| allocate_if_necessary(); |
| for (int i = 0; i < other._replaced_nodes->length(); i++) { |
| ReplacedNode replaced = other._replaced_nodes->at(i); |
| // Only transfer the nodes that can actually be useful |
| if (!has_node(replaced) && (replaced.initial()->_idx < idx || has_target_node(replaced.initial()))) { |
| _replaced_nodes->push(replaced); |
| } |
| } |
| } |
| |
| void ReplacedNodes::clone() { |
| if (_replaced_nodes != NULL) { |
| GrowableArray<ReplacedNode>* replaced_nodes_clone = new GrowableArray<ReplacedNode>(); |
| replaced_nodes_clone->appendAll(_replaced_nodes); |
| _replaced_nodes = replaced_nodes_clone; |
| } |
| } |
| |
| void ReplacedNodes::reset() { |
| if (_replaced_nodes != NULL) { |
| _replaced_nodes->clear(); |
| } |
| } |
| |
| // Perfom node replacement (used when returning to caller) |
| void ReplacedNodes::apply(Node* n, uint idx) { |
| if (is_empty()) { |
| return; |
| } |
| for (int i = 0; i < _replaced_nodes->length(); i++) { |
| ReplacedNode replaced = _replaced_nodes->at(i); |
| // Only apply if improved node was created in a callee to avoid |
| // issues with irreducible loops in the caller |
| if (replaced.improved()->_idx >= idx) { |
| n->replace_edge(replaced.initial(), replaced.improved()); |
| } |
| } |
| } |
| |
| static void enqueue_use(Node* n, Node* use, Unique_Node_List& work) { |
| if (use->is_Phi()) { |
| Node* r = use->in(0); |
| assert(r->is_Region(), "Phi should have Region"); |
| for (uint i = 1; i < use->req(); i++) { |
| if (use->in(i) == n) { |
| work.push(r->in(i)); |
| } |
| } |
| } else { |
| work.push(use); |
| } |
| } |
| |
| // Perfom node replacement following late inlining |
| void ReplacedNodes::apply(Compile* C, Node* ctl) { |
| // ctl is the control on exit of the method that was late inlined |
| if (is_empty()) { |
| return; |
| } |
| for (int i = 0; i < _replaced_nodes->length(); i++) { |
| ReplacedNode replaced = _replaced_nodes->at(i); |
| Node* initial = replaced.initial(); |
| Node* improved = replaced.improved(); |
| assert (ctl != NULL && !ctl->is_top(), "replaced node should have actual control"); |
| |
| ResourceMark rm; |
| Unique_Node_List work; |
| // Go over all the uses of the node that is considered for replacement... |
| for (DUIterator j = initial->outs(); initial->has_out(j); j++) { |
| Node* use = initial->out(j); |
| |
| if (use == improved || use->outcnt() == 0) { |
| continue; |
| } |
| work.clear(); |
| enqueue_use(initial, use, work); |
| bool replace = true; |
| // Check that this use is dominated by ctl. Go ahead with the |
| // replacement if it is. |
| while (work.size() != 0 && replace) { |
| Node* n = work.pop(); |
| if (use->outcnt() == 0) { |
| continue; |
| } |
| if (n->is_CFG() || (n->in(0) != NULL && !n->in(0)->is_top())) { |
| int depth = 0; |
| Node *m = n; |
| if (!n->is_CFG()) { |
| n = n->in(0); |
| } |
| assert(n->is_CFG(), "should be CFG now"); |
| while(n != ctl) { |
| n = IfNode::up_one_dom(n); |
| depth++; |
| // limit search depth |
| if (depth >= 100 || n == NULL) { |
| replace = false; |
| break; |
| } |
| } |
| } else { |
| for (DUIterator k = n->outs(); n->has_out(k); k++) { |
| enqueue_use(n, n->out(k), work); |
| } |
| } |
| } |
| if (replace) { |
| bool is_in_table = C->initial_gvn()->hash_delete(use); |
| int replaced = use->replace_edge(initial, improved); |
| if (is_in_table) { |
| C->initial_gvn()->hash_find_insert(use); |
| } |
| C->record_for_igvn(use); |
| |
| assert(replaced > 0, "inconsistent"); |
| --j; |
| } |
| } |
| } |
| } |
| |
| void ReplacedNodes::dump(outputStream *st) const { |
| if (!is_empty()) { |
| st->print("replaced nodes: "); |
| for (int i = 0; i < _replaced_nodes->length(); i++) { |
| st->print("%d->%d", _replaced_nodes->at(i).initial()->_idx, _replaced_nodes->at(i).improved()->_idx); |
| if (i < _replaced_nodes->length()-1) { |
| st->print(","); |
| } |
| } |
| } |
| } |
| |
| // Merge 2 list of replaced node at a point where control flow paths merge |
| void ReplacedNodes::merge_with(const ReplacedNodes& other) { |
| if (is_empty()) { |
| return; |
| } |
| if (other.is_empty()) { |
| reset(); |
| return; |
| } |
| int shift = 0; |
| int len = _replaced_nodes->length(); |
| for (int i = 0; i < len; i++) { |
| if (!other.has_node(_replaced_nodes->at(i))) { |
| shift++; |
| } else if (shift > 0) { |
| _replaced_nodes->at_put(i-shift, _replaced_nodes->at(i)); |
| } |
| } |
| if (shift > 0) { |
| _replaced_nodes->trunc_to(len - shift); |
| } |
| } |