| /* |
| * Copyright (c) 2009, 2014, 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 org.graalvm.compiler.nodes.calc; |
| |
| import static org.graalvm.compiler.nodeinfo.NodeCycles.CYCLES_0; |
| import static org.graalvm.compiler.nodeinfo.NodeSize.SIZE_2; |
| import static org.graalvm.compiler.nodes.calc.CompareNode.createCompareNode; |
| |
| import org.graalvm.compiler.core.common.calc.Condition; |
| import org.graalvm.compiler.core.common.type.IntegerStamp; |
| import org.graalvm.compiler.core.common.type.Stamp; |
| import org.graalvm.compiler.core.common.type.StampFactory; |
| import org.graalvm.compiler.graph.NodeClass; |
| import org.graalvm.compiler.graph.spi.Canonicalizable; |
| import org.graalvm.compiler.graph.spi.CanonicalizerTool; |
| import org.graalvm.compiler.nodeinfo.InputType; |
| import org.graalvm.compiler.nodeinfo.NodeInfo; |
| import org.graalvm.compiler.nodes.ConstantNode; |
| import org.graalvm.compiler.nodes.LogicConstantNode; |
| import org.graalvm.compiler.nodes.LogicNegationNode; |
| import org.graalvm.compiler.nodes.LogicNode; |
| import org.graalvm.compiler.nodes.StructuredGraph; |
| import org.graalvm.compiler.nodes.ValueNode; |
| import org.graalvm.compiler.nodes.spi.LIRLowerable; |
| import org.graalvm.compiler.nodes.spi.NodeLIRBuilderTool; |
| |
| import jdk.vm.ci.meta.JavaConstant; |
| |
| /** |
| * The {@code ConditionalNode} class represents a comparison that yields one of two values. Note |
| * that these nodes are not built directly from the bytecode but are introduced by canonicalization. |
| */ |
| @NodeInfo(cycles = CYCLES_0, size = SIZE_2) |
| public final class ConditionalNode extends FloatingNode implements Canonicalizable, LIRLowerable { |
| |
| public static final NodeClass<ConditionalNode> TYPE = NodeClass.create(ConditionalNode.class); |
| @Input(InputType.Condition) LogicNode condition; |
| @Input ValueNode trueValue; |
| @Input ValueNode falseValue; |
| |
| public LogicNode condition() { |
| return condition; |
| } |
| |
| public ConditionalNode(LogicNode condition) { |
| this(condition, ConstantNode.forInt(1, condition.graph()), ConstantNode.forInt(0, condition.graph())); |
| } |
| |
| public ConditionalNode(LogicNode condition, ValueNode trueValue, ValueNode falseValue) { |
| super(TYPE, trueValue.stamp().meet(falseValue.stamp())); |
| assert trueValue.stamp().isCompatible(falseValue.stamp()); |
| this.condition = condition; |
| this.trueValue = trueValue; |
| this.falseValue = falseValue; |
| } |
| |
| public static ValueNode create(LogicNode condition) { |
| return create(condition, ConstantNode.forInt(1, condition.graph()), ConstantNode.forInt(0, condition.graph())); |
| } |
| |
| public static ValueNode create(LogicNode condition, ValueNode trueValue, ValueNode falseValue) { |
| ValueNode synonym = findSynonym(condition, trueValue, falseValue); |
| if (synonym != null) { |
| return synonym; |
| } |
| return new ConditionalNode(condition, trueValue, falseValue); |
| } |
| |
| @Override |
| public boolean inferStamp() { |
| Stamp valueStamp = trueValue.stamp().meet(falseValue.stamp()); |
| if (condition instanceof IntegerLessThanNode) { |
| IntegerLessThanNode lessThan = (IntegerLessThanNode) condition; |
| if (lessThan.getX() == trueValue && lessThan.getY() == falseValue) { |
| // this encodes a min operation |
| JavaConstant constant = lessThan.getX().asJavaConstant(); |
| if (constant == null) { |
| constant = lessThan.getY().asJavaConstant(); |
| } |
| if (constant != null) { |
| IntegerStamp bounds = StampFactory.forInteger(constant.getJavaKind(), constant.getJavaKind().getMinValue(), constant.asLong()); |
| valueStamp = valueStamp.join(bounds); |
| } |
| } else if (lessThan.getX() == falseValue && lessThan.getY() == trueValue) { |
| // this encodes a max operation |
| JavaConstant constant = lessThan.getX().asJavaConstant(); |
| if (constant == null) { |
| constant = lessThan.getY().asJavaConstant(); |
| } |
| if (constant != null) { |
| IntegerStamp bounds = StampFactory.forInteger(constant.getJavaKind(), constant.asLong(), constant.getJavaKind().getMaxValue()); |
| valueStamp = valueStamp.join(bounds); |
| } |
| } |
| |
| } |
| return updateStamp(valueStamp); |
| } |
| |
| public ValueNode trueValue() { |
| return trueValue; |
| } |
| |
| public ValueNode falseValue() { |
| return falseValue; |
| } |
| |
| @Override |
| public ValueNode canonical(CanonicalizerTool tool) { |
| ValueNode synonym = findSynonym(condition, trueValue(), falseValue()); |
| if (synonym != null) { |
| return synonym; |
| } |
| |
| ValueNode result = canonicalizeConditional(condition, trueValue(), falseValue(), stamp); |
| if (result != null) { |
| return result; |
| } |
| |
| return this; |
| } |
| |
| public static ValueNode canonicalizeConditional(LogicNode condition, ValueNode trueValue, ValueNode falseValue, Stamp stamp) { |
| // this optimizes the case where a value that can only be 0 or 1 is materialized to 0 or 1 |
| if (trueValue.isConstant() && falseValue.isConstant() && condition instanceof IntegerEqualsNode) { |
| IntegerEqualsNode equals = (IntegerEqualsNode) condition; |
| if (equals.getY().isConstant() && equals.getY().asConstant().equals(JavaConstant.INT_0) && equals.getX().stamp() instanceof IntegerStamp) { |
| IntegerStamp equalsXStamp = (IntegerStamp) equals.getX().stamp(); |
| if (equalsXStamp.upMask() == 1) { |
| if (trueValue.asConstant().equals(JavaConstant.INT_0) && falseValue.asConstant().equals(JavaConstant.INT_1)) { |
| return IntegerConvertNode.convertUnsigned(equals.getX(), stamp); |
| } |
| } |
| } |
| } |
| if (condition instanceof CompareNode && ((CompareNode) condition).isIdentityComparison()) { |
| // optimize the pattern (x == y) ? x : y |
| CompareNode compare = (CompareNode) condition; |
| if ((compare.getX() == trueValue && compare.getY() == falseValue) || (compare.getX() == falseValue && compare.getY() == trueValue)) { |
| return falseValue; |
| } |
| } |
| if (trueValue == falseValue) { |
| return trueValue; |
| } |
| |
| if (condition instanceof IntegerLessThanNode && trueValue.stamp() instanceof IntegerStamp) { |
| /* |
| * Convert a conditional add ((x < 0) ? (x + y) : x) into (x + (y & (x >> (bits - 1)))) |
| * to avoid the test. |
| */ |
| IntegerLessThanNode lt = (IntegerLessThanNode) condition; |
| if (lt.getY().isConstant() && lt.getY().asConstant().isDefaultForKind()) { |
| if (falseValue == lt.getX()) { |
| if (trueValue instanceof AddNode) { |
| AddNode add = (AddNode) trueValue; |
| if (add.getX() == falseValue) { |
| int bits = ((IntegerStamp) trueValue.stamp()).getBits(); |
| ValueNode shift = new RightShiftNode(lt.getX(), ConstantNode.forIntegerBits(32, bits - 1)); |
| ValueNode and = new AndNode(shift, add.getY()); |
| return new AddNode(add.getX(), and); |
| } |
| } |
| } |
| } |
| } |
| |
| return null; |
| } |
| |
| private static ValueNode findSynonym(ValueNode condition, ValueNode trueValue, ValueNode falseValue) { |
| if (condition instanceof LogicNegationNode) { |
| LogicNegationNode negated = (LogicNegationNode) condition; |
| return ConditionalNode.create(negated.getValue(), falseValue, trueValue); |
| } |
| if (condition instanceof LogicConstantNode) { |
| LogicConstantNode c = (LogicConstantNode) condition; |
| if (c.getValue()) { |
| return trueValue; |
| } else { |
| return falseValue; |
| } |
| } |
| return null; |
| } |
| |
| @Override |
| public void generate(NodeLIRBuilderTool generator) { |
| generator.emitConditional(this); |
| } |
| |
| public ConditionalNode(StructuredGraph graph, Condition condition, ValueNode x, ValueNode y) { |
| this(createCompareNode(graph, condition, x, y, null)); |
| } |
| } |
