Mercurial > hg > truffle
view graal/com.oracle.graal.replacements.amd64/src/com/oracle/graal/replacements/amd64/AMD64CountTrailingZerosNode.java @ 21142:0b221b4ad707
Merge
author | Tom Rodriguez <tom.rodriguez@oracle.com> |
---|---|
date | Tue, 28 Apr 2015 12:58:40 -0700 |
parents | 9794217565cd |
children | 48c1ebd24120 |
line wrap: on
line source
/* * Copyright (c) 2012, 2015, 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.graal.replacements.amd64; import com.oracle.graal.api.code.*; import com.oracle.graal.api.meta.*; import com.oracle.graal.compiler.common.type.*; import com.oracle.graal.graph.*; import com.oracle.graal.graph.spi.*; import com.oracle.graal.nodeinfo.*; import com.oracle.graal.nodes.*; import com.oracle.graal.nodes.calc.*; import com.oracle.graal.nodes.spi.*; /** * Count the number of trailing zeros using the {@code tzcntq} or {@code tzcntl} instructions. */ @NodeInfo public final class AMD64CountTrailingZerosNode extends UnaryNode implements LIRLowerable { public static final NodeClass<AMD64CountTrailingZerosNode> TYPE = NodeClass.create(AMD64CountTrailingZerosNode.class); public AMD64CountTrailingZerosNode(ValueNode value) { super(TYPE, StampFactory.forInteger(Kind.Int, 0, ((PrimitiveStamp) value.stamp()).getBits()), value); assert value.getKind() == Kind.Int || value.getKind() == Kind.Long; } @Override public boolean inferStamp() { IntegerStamp valueStamp = (IntegerStamp) getValue().stamp(); long mask = CodeUtil.mask(valueStamp.getBits()); int min = Long.numberOfTrailingZeros(valueStamp.upMask() & mask); int max = Long.numberOfTrailingZeros(valueStamp.downMask() & mask); return updateStamp(StampFactory.forInteger(Kind.Int, min, max)); } public static ValueNode tryFold(ValueNode value) { if (value.isConstant()) { JavaConstant c = value.asJavaConstant(); if (value.getKind() == Kind.Int) { return ConstantNode.forInt(Integer.numberOfTrailingZeros(c.asInt())); } else { return ConstantNode.forInt(Long.numberOfTrailingZeros(c.asLong())); } } return null; } @Override public ValueNode canonical(CanonicalizerTool tool, ValueNode forValue) { ValueNode folded = tryFold(forValue); return folded != null ? folded : this; } @Override public void generate(NodeLIRBuilderTool gen) { Value result = gen.getLIRGeneratorTool().emitCountTrailingZeros(gen.operand(getValue())); gen.setResult(this, result); } }