Mercurial > hg > truffle
view graal/com.oracle.max.graal.compiler/src/com/oracle/max/graal/compiler/ir/Phi.java @ 2984:f49685081630
Merge
author | Gilles Duboscq <gilles.duboscq@oracle.com> |
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date | Wed, 15 Jun 2011 19:54:42 +0200 |
parents | fc66984c2f31 42681ed31c4d |
children | 2f5f6ffbafa0 0c519981c6cf |
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/* * Copyright (c) 2009, 2011, 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. */ package com.oracle.max.graal.compiler.ir; import com.oracle.max.graal.compiler.debug.*; import com.oracle.max.graal.graph.*; import com.sun.cri.ci.*; /** * The {@code Phi} instruction represents the merging of dataflow * in the instruction graph. It refers to a join block and a variable. */ public final class Phi extends FloatingNode { private static final int DEFAULT_MAX_VALUES = 2; private static final int INPUT_COUNT = 1; private static final int INPUT_MERGE = 0; private static final int SUCCESSOR_COUNT = 0; private boolean isDead; @Override protected int inputCount() { return super.inputCount() + INPUT_COUNT; } @Override protected int successorCount() { return super.successorCount() + SUCCESSOR_COUNT; } /** * The merge node for this phi. */ public Merge merge() { return (Merge) inputs().get(super.inputCount() + INPUT_MERGE); } public void setMerge(Value n) { inputs().set(super.inputCount() + INPUT_MERGE, n); } public Phi(CiKind kind, Merge merge, Graph graph) { super(kind, INPUT_COUNT, SUCCESSOR_COUNT, graph); setMerge(merge); } /** * Get the instruction that produces the value associated with the i'th predecessor * of the join block. * @param i the index of the predecessor * @return the instruction that produced the value in the i'th predecessor */ public Value valueAt(int i) { return (Value) inputs().variablePart().get(i); } public void setValueAt(int i, Value x) { inputs().set(INPUT_COUNT + i, x); } /** * Get the number of inputs to this phi (i.e. the number of predecessors to the join block). * @return the number of inputs in this phi */ public int valueCount() { return inputs().variablePart().size(); } @Override public void accept(ValueVisitor v) { v.visitPhi(this); } /** * Make this phi illegal if types were not merged correctly. */ public void makeDead() { isDead = true; } public boolean isDead() { return isDead; } @Override public void print(LogStream out) { out.print("phi function ("); for (int i = 0; i < valueCount(); ++i) { if (i != 0) { out.print(' '); } out.print(valueAt(i)); } out.print(')'); } @Override public String shortName() { StringBuilder str = new StringBuilder(); for (int i = 0; i < valueCount(); ++i) { if (i != 0) { str.append(' '); } str.append(valueAt(i) == null ? "-" : valueAt(i).id()); } return "Phi: (" + str + ")"; } public void addInput(Node y) { inputs().variablePart().add(y); } public void removeInput(int index) { inputs().variablePart().remove(index); } @Override public Node copy(Graph into) { Phi x = new Phi(kind, null, into); x.isDead = isDead; return x; } }