1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/src/share/vm/opto/mathexactnode.cpp Fri Sep 27 08:39:19 2013 +0200
1.3 @@ -0,0 +1,143 @@
1.4 +/*
1.5 + * Copyright (c) 2013, Oracle and/or its affiliates. All rights reserved.
1.6 + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
1.7 + *
1.8 + * This code is free software; you can redistribute it and/or modify it
1.9 + * under the terms of the GNU General Public License version 2 only, as
1.10 + * published by the Free Software Foundation.
1.11 + *
1.12 + * This code is distributed in the hope that it will be useful, but WITHOUT
1.13 + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
1.14 + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
1.15 + * version 2 for more details (a copy is included in the LICENSE file that
1.16 + * accompanied this code).
1.17 + *
1.18 + * You should have received a copy of the GNU General Public License version
1.19 + * 2 along with this work; if not, write to the Free Software Foundation,
1.20 + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
1.21 + *
1.22 + * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
1.23 + * or visit www.oracle.com if you need additional information or have any
1.24 + * questions.
1.25 + *
1.26 + */
1.27 +
1.28 +#include "precompiled.hpp"
1.29 +#include "memory/allocation.inline.hpp"
1.30 +#include "opto/addnode.hpp"
1.31 +#include "opto/machnode.hpp"
1.32 +#include "opto/mathexactnode.hpp"
1.33 +#include "opto/matcher.hpp"
1.34 +#include "opto/subnode.hpp"
1.35 +
1.36 +MathExactNode::MathExactNode(Node* ctrl, Node* n1, Node* n2) : MultiNode(3) {
1.37 + init_req(0, ctrl);
1.38 + init_req(1, n1);
1.39 + init_req(2, n2);
1.40 +}
1.41 +
1.42 +Node* AddExactINode::match(const ProjNode* proj, const Matcher* m) {
1.43 + uint ideal_reg = proj->ideal_reg();
1.44 + RegMask rm;
1.45 + if (proj->_con == result_proj_node) {
1.46 + rm = m->mathExactI_result_proj_mask();
1.47 + } else {
1.48 + assert(proj->_con == flags_proj_node, "must be result or flags");
1.49 + assert(ideal_reg == Op_RegFlags, "sanity");
1.50 + rm = m->mathExactI_flags_proj_mask();
1.51 + }
1.52 + return new (m->C) MachProjNode(this, proj->_con, rm, ideal_reg);
1.53 +}
1.54 +
1.55 +// If the MathExactNode won't overflow we have to replace the
1.56 +// FlagsProjNode and ProjNode that is generated by the MathExactNode
1.57 +Node* MathExactNode::no_overflow(PhaseGVN *phase, Node* new_result) {
1.58 + PhaseIterGVN *igvn = phase->is_IterGVN();
1.59 + if (igvn) {
1.60 + ProjNode* result = result_node();
1.61 + ProjNode* flags = flags_node();
1.62 +
1.63 + if (result != NULL) {
1.64 + igvn->replace_node(result, new_result);
1.65 + }
1.66 +
1.67 + if (flags != NULL) {
1.68 + BoolNode* bolnode = (BoolNode *) flags->unique_out();
1.69 + switch (bolnode->_test._test) {
1.70 + case BoolTest::overflow:
1.71 + // if the check is for overflow - never taken
1.72 + igvn->replace_node(bolnode, phase->intcon(0));
1.73 + break;
1.74 + case BoolTest::no_overflow:
1.75 + // if the check is for no overflow - always taken
1.76 + igvn->replace_node(bolnode, phase->intcon(1));
1.77 + break;
1.78 + default:
1.79 + fatal("Unexpected value of BoolTest");
1.80 + break;
1.81 + }
1.82 + flags->del_req(0);
1.83 + }
1.84 + }
1.85 + return new_result;
1.86 +}
1.87 +
1.88 +Node *AddExactINode::Ideal(PhaseGVN *phase, bool can_reshape) {
1.89 + Node *arg1 = in(1);
1.90 + Node *arg2 = in(2);
1.91 +
1.92 + const Type* type1 = phase->type(arg1);
1.93 + const Type* type2 = phase->type(arg2);
1.94 +
1.95 + if (type1 != Type::TOP && type1->singleton() &&
1.96 + type2 != Type::TOP && type2->singleton()) {
1.97 + jint val1 = arg1->get_int();
1.98 + jint val2 = arg2->get_int();
1.99 + jint result = val1 + val2;
1.100 + // Hacker's Delight 2-12 Overflow if both arguments have the opposite sign of the result
1.101 + if ( (((val1 ^ result) & (val2 ^ result)) >= 0)) {
1.102 + Node* con_result = ConINode::make(phase->C, result);
1.103 + return no_overflow(phase, con_result);
1.104 + }
1.105 + return NULL;
1.106 + }
1.107 +
1.108 + if (type1 == TypeInt::ZERO) { // (Add 0 x) == x
1.109 + Node* add_result = new (phase->C) AddINode(arg1, arg2);
1.110 + return no_overflow(phase, add_result);
1.111 + }
1.112 +
1.113 + if (type2 == TypeInt::ZERO) { // (Add x 0) == x
1.114 + Node* add_result = new (phase->C) AddINode(arg1, arg2);
1.115 + return no_overflow(phase, add_result);
1.116 + }
1.117 +
1.118 + if (type2->singleton()) {
1.119 + return NULL; // no change - keep constant on the right
1.120 + }
1.121 +
1.122 + if (type1->singleton()) {
1.123 + // Make it x + Constant - move constant to the right
1.124 + swap_edges(1, 2);
1.125 + return this;
1.126 + }
1.127 +
1.128 + if (arg2->is_Load()) {
1.129 + return NULL; // no change - keep load on the right
1.130 + }
1.131 +
1.132 + if (arg1->is_Load()) {
1.133 + // Make it x + Load - move load to the right
1.134 + swap_edges(1, 2);
1.135 + return this;
1.136 + }
1.137 +
1.138 + if (arg1->_idx > arg2->_idx) {
1.139 + // Sort the edges
1.140 + swap_edges(1, 2);
1.141 + return this;
1.142 + }
1.143 +
1.144 + return NULL;
1.145 +}
1.146 +
