Mercurial > hg > truffle
view graal/GraalCompiler/src/com/sun/c1x/ir/Phi.java @ 2779:93ec3f067420
Changed CriticalEdgeFinder to use LIRBlock.
author | Thomas Wuerthinger <thomas@wuerthinger.net> |
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date | Wed, 25 May 2011 11:04:59 +0200 |
parents | 3e3338a1abb9 |
children | d3fc4fe063bf |
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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.sun.c1x.ir; import com.oracle.graal.graph.*; import com.sun.c1x.debug.*; 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 Value { private static final int DEFAULT_MAX_VALUES = 2; private static final int INPUT_COUNT = 1; private static final int INPUT_BLOCK = 0; private static final int SUCCESSOR_COUNT = 0; private int usedInputCount; @Override protected int successorCount() { return super.successorCount() + SUCCESSOR_COUNT; } /** * The join block for this phi. */ @Override public BlockBegin block() { return (BlockBegin) inputs().get(super.inputCount() + INPUT_BLOCK); } public Value setBlock(Value n) { return (BlockBegin) inputs().set(super.inputCount() + INPUT_BLOCK, n); } /** * Create a new Phi for the specified join block and local variable (or operand stack) slot. * @param kind the type of the variable * @param block the join point * @param index the index into the stack (if < 0) or local variables * @param graph */ public Phi(CiKind kind, BlockBegin block, Graph graph) { this(kind, block, DEFAULT_MAX_VALUES, graph); } public Phi(CiKind kind, BlockBegin block, int maxValues, Graph graph) { super(kind, INPUT_COUNT + maxValues, SUCCESSOR_COUNT, graph); usedInputCount = 1; setBlock(block); } /** * 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().get(i + INPUT_COUNT); } /** * 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 usedInputCount - 1; } @Override public void accept(ValueVisitor v) { v.visitPhi(this); } /** * Make this phi illegal if types were not merged correctly. */ public void makeDead() { setFlag(Flag.PhiCannotSimplify); setFlag(Flag.PhiDead); } @Override public void print(LogStream out) { out.print("phi function ("); for (int i = 0; i < inputs().size(); ++i) { if (i != 0) { out.print(' '); } out.print((Value) inputs().get(i)); } out.print(')'); } @Override public String shortName() { return "Phi: (" + valueCount() + ")"; } public Phi addInput(Node y) { assert !this.isDeleted() && !y.isDeleted(); Phi phi = this; if (usedInputCount == inputs().size()) { phi = new Phi(kind, block(), usedInputCount * 2, graph()); for (int i = 0; i < valueCount(); ++i) { phi.addInput(valueAt(i)); } phi.addInput(y); this.replace(phi); } else { phi.inputs().set(usedInputCount++, y); } return phi; } public void removeInput(int index) { inputs().set(index, null); for (int i = index + 1; i < usedInputCount; ++i) { inputs().set(i - 1, inputs().get(i)); } usedInputCount--; } }