--- /dev/null 2016-05-31 09:42:47.975716356 -0700 +++ new/src/jdk.vm.compiler/share/classes/org.graalvm.compiler.nodes/src/org/graalvm/compiler/nodes/calc/CompareNode.java 2016-12-09 00:55:13.308476263 -0800 @@ -0,0 +1,258 @@ +/* + * Copyright (c) 2011, 2016, 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.core.common.GraalOptions.GeneratePIC; +import static org.graalvm.compiler.nodeinfo.NodeCycles.CYCLES_1; + +import org.graalvm.compiler.core.common.calc.Condition; +import org.graalvm.compiler.core.common.type.AbstractObjectStamp; +import org.graalvm.compiler.core.common.type.AbstractPointerStamp; +import org.graalvm.compiler.core.common.type.IntegerStamp; +import org.graalvm.compiler.debug.GraalError; +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.NodeInfo; +import org.graalvm.compiler.nodes.BinaryOpLogicNode; +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 jdk.vm.ci.meta.Constant; +import jdk.vm.ci.meta.ConstantReflectionProvider; + +/* TODO (thomaswue/gdub) For high-level optimization purpose the compare node should be a boolean *value* (it is currently only a helper node) + * But in the back-end the comparison should not always be materialized (for example in x86 the comparison result will not be in a register but in a flag) + * + * Compare should probably be made a value (so that it can be canonicalized for example) and in later stages some Compare usage should be transformed + * into variants that do not materialize the value (CompareIf, CompareGuard...) + */ +@NodeInfo(cycles = CYCLES_1) +public abstract class CompareNode extends BinaryOpLogicNode implements Canonicalizable.Binary { + + public static final NodeClass TYPE = NodeClass.create(CompareNode.class); + protected final Condition condition; + protected final boolean unorderedIsTrue; + + /** + * Constructs a new Compare instruction. + * + * @param x the instruction producing the first input to the instruction + * @param y the instruction that produces the second input to this instruction + */ + protected CompareNode(NodeClass c, Condition condition, boolean unorderedIsTrue, ValueNode x, ValueNode y) { + super(c, x, y); + this.condition = condition; + this.unorderedIsTrue = unorderedIsTrue; + } + + /** + * Gets the condition (comparison operation) for this instruction. + * + * @return the condition + */ + public final Condition condition() { + return condition; + } + + /** + * Checks whether unordered inputs mean true or false (only applies to float operations). + * + * @return {@code true} if unordered inputs produce true + */ + public final boolean unorderedIsTrue() { + return this.unorderedIsTrue; + } + + private ValueNode optimizeConditional(Constant constant, ConditionalNode conditionalNode, ConstantReflectionProvider constantReflection, Condition cond) { + Constant trueConstant = conditionalNode.trueValue().asConstant(); + Constant falseConstant = conditionalNode.falseValue().asConstant(); + + if (falseConstant != null && trueConstant != null && constantReflection != null) { + boolean trueResult = cond.foldCondition(trueConstant, constant, constantReflection, unorderedIsTrue()); + boolean falseResult = cond.foldCondition(falseConstant, constant, constantReflection, unorderedIsTrue()); + + if (trueResult == falseResult) { + return LogicConstantNode.forBoolean(trueResult); + } else { + if (trueResult) { + assert falseResult == false; + return conditionalNode.condition(); + } else { + assert falseResult == true; + return LogicNegationNode.create(conditionalNode.condition()); + + } + } + } + return this; + } + + protected ValueNode optimizeNormalizeCmp(Constant constant, NormalizeCompareNode normalizeNode, boolean mirrored) { + throw new GraalError("NormalizeCompareNode connected to %s (%s %s %s)", this, constant, normalizeNode, mirrored); + } + + @Override + public ValueNode canonical(CanonicalizerTool tool, ValueNode forX, ValueNode forY) { + ConstantReflectionProvider constantReflection = tool.getConstantReflection(); + LogicNode constantCondition = tryConstantFold(condition(), forX, forY, constantReflection, unorderedIsTrue()); + if (constantCondition != null) { + return constantCondition; + } + ValueNode result; + if (forX.isConstant()) { + if ((result = canonicalizeSymmetricConstant(tool, forX.asConstant(), forY, true)) != this) { + return result; + } + } else if (forY.isConstant()) { + if ((result = canonicalizeSymmetricConstant(tool, forY.asConstant(), forX, false)) != this) { + return result; + } + } else if (forX instanceof ConvertNode && forY instanceof ConvertNode) { + ConvertNode convertX = (ConvertNode) forX; + ConvertNode convertY = (ConvertNode) forY; + if (convertX.preservesOrder(condition()) && convertY.preservesOrder(condition()) && convertX.getValue().stamp().isCompatible(convertY.getValue().stamp())) { + boolean supported = true; + if (convertX.getValue().stamp() instanceof IntegerStamp) { + IntegerStamp intStamp = (IntegerStamp) convertX.getValue().stamp(); + supported = tool.supportSubwordCompare(intStamp.getBits()); + } + + if (supported) { + boolean multiUsage = (convertX.asNode().getUsageCount() > 1 || convertY.asNode().getUsageCount() > 1); + if ((forX instanceof ZeroExtendNode || forX instanceof SignExtendNode) && multiUsage) { + // Do not perform for zero or sign extend if there are multiple usages of + // the value. + return this; + } + return duplicateModified(convertX.getValue(), convertY.getValue()); + } + } + } + return this; + } + + public static LogicNode tryConstantFold(Condition condition, ValueNode forX, ValueNode forY, ConstantReflectionProvider constantReflection, boolean unorderedIsTrue) { + if (forX.isConstant() && forY.isConstant() && constantReflection != null) { + return LogicConstantNode.forBoolean(condition.foldCondition(forX.asConstant(), forY.asConstant(), constantReflection, unorderedIsTrue)); + } + return null; + } + + /** + * Does this operation represent an identity check such that for x == y, x is exactly the same + * thing as y. This is generally true except for some floating point comparisons. + * + * @return true for identity comparisons + */ + public boolean isIdentityComparison() { + return condition == Condition.EQ; + } + + protected abstract LogicNode duplicateModified(ValueNode newX, ValueNode newY); + + protected ValueNode canonicalizeSymmetricConstant(CanonicalizerTool tool, Constant constant, ValueNode nonConstant, boolean mirrored) { + if (nonConstant instanceof ConditionalNode) { + return optimizeConditional(constant, (ConditionalNode) nonConstant, tool.getConstantReflection(), mirrored ? condition().mirror() : condition()); + } else if (nonConstant instanceof NormalizeCompareNode) { + return optimizeNormalizeCmp(constant, (NormalizeCompareNode) nonConstant, mirrored); + } else if (nonConstant instanceof ConvertNode) { + ConvertNode convert = (ConvertNode) nonConstant; + boolean multiUsage = (convert.asNode().getUsageCount() > 1 && convert.getValue().getUsageCount() == 1); + if ((convert instanceof ZeroExtendNode || convert instanceof SignExtendNode) && multiUsage) { + // Do not perform for zero or sign extend if it could introduce + // new live values. + return this; + } + + boolean supported = true; + if (convert.getValue().stamp() instanceof IntegerStamp) { + IntegerStamp intStamp = (IntegerStamp) convert.getValue().stamp(); + supported = tool.supportSubwordCompare(intStamp.getBits()); + } + + if (supported) { + ConstantNode newConstant = canonicalConvertConstant(tool, convert, constant); + if (newConstant != null) { + if (mirrored) { + return duplicateModified(newConstant, convert.getValue()); + } else { + return duplicateModified(convert.getValue(), newConstant); + } + } + } + } + return this; + } + + private ConstantNode canonicalConvertConstant(CanonicalizerTool tool, ConvertNode convert, Constant constant) { + ConstantReflectionProvider constantReflection = tool.getConstantReflection(); + if (convert.preservesOrder(condition(), constant, constantReflection)) { + Constant reverseConverted = convert.reverse(constant, constantReflection); + if (reverseConverted != null && convert.convert(reverseConverted, constantReflection).equals(constant)) { + if (GeneratePIC.getValue()) { + // We always want uncompressed constants + return null; + } + return ConstantNode.forConstant(convert.getValue().stamp(), reverseConverted, tool.getMetaAccess()); + } + } + return null; + } + + public static LogicNode createCompareNode(StructuredGraph graph, Condition condition, ValueNode x, ValueNode y, ConstantReflectionProvider constantReflection) { + LogicNode result = createCompareNode(condition, x, y, constantReflection); + return (result.graph() == null ? graph.unique(result) : result); + } + + public static LogicNode createCompareNode(Condition condition, ValueNode x, ValueNode y, ConstantReflectionProvider constantReflection) { + assert x.getStackKind() == y.getStackKind(); + assert condition.isCanonical() : "condition is not canonical: " + condition; + assert !x.getStackKind().isNumericFloat(); + + LogicNode comparison; + if (condition == Condition.EQ) { + if (x.stamp() instanceof AbstractObjectStamp) { + comparison = ObjectEqualsNode.create(x, y, constantReflection); + } else if (x.stamp() instanceof AbstractPointerStamp) { + comparison = PointerEqualsNode.create(x, y); + } else { + assert x.getStackKind().isNumericInteger(); + comparison = IntegerEqualsNode.create(x, y, constantReflection); + } + } else if (condition == Condition.LT) { + assert x.getStackKind().isNumericInteger(); + comparison = IntegerLessThanNode.create(x, y, constantReflection); + } else { + assert condition == Condition.BT; + assert x.getStackKind().isNumericInteger(); + comparison = IntegerBelowNode.create(x, y, constantReflection); + } + + return comparison; + } +}