--- /dev/null 2016-05-31 09:42:47.975716356 -0700 +++ new/src/jdk.vm.compiler/share/classes/org.graalvm.compiler.core.test/src/org/graalvm/compiler/core/test/StampCanonicalizerTest.java 2016-12-09 00:47:46.414777579 -0800 @@ -0,0 +1,118 @@ +/* + * Copyright (c) 2012, 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.core.test; + +import org.junit.Test; + +import org.graalvm.compiler.core.common.type.IntegerStamp; +import org.graalvm.compiler.nodes.StructuredGraph; +import org.graalvm.compiler.nodes.StructuredGraph.AllowAssumptions; +import org.graalvm.compiler.phases.common.CanonicalizerPhase; +import org.graalvm.compiler.phases.common.DeadCodeEliminationPhase; +import org.graalvm.compiler.phases.tiers.PhaseContext; + +/** + * This class tests some specific patterns the stamp system should be able to canonicalize away + * using {@link IntegerStamp#upMask()}. + */ +public class StampCanonicalizerTest extends GraalCompilerTest { + + public static int andStamp(int a, int b) { + int v = (a & 0xffff00) & (b & 0xff0000f); + return v & 1; + } + + @Test + public void testAnd() { + testZeroReturn("andStamp"); + } + + public static int shiftLeftStamp1(int a) { + int v = a << 1; + return v & 1; + } + + public static int shiftLeftStamp2(int a) { + int v = a << 1; + if (a == 17) { + v = a * 4; + } + return v & 1; + } + + @Test + public void testShift() { + testZeroReturn("shiftLeftStamp1"); + testZeroReturn("shiftLeftStamp2"); + } + + public static int upperBoundShiftStamp1(int a) { + int v = a & 0xffff; + return (v << 4) & 0xff00000; + } + + public static int upperBoundShiftStamp2(int a) { + int v = a & 0xffff; + return (v >> 4) & 0xf000; + } + + @Test + public void testUpperBoundShift() { + testZeroReturn("upperBoundShiftStamp1"); + testZeroReturn("upperBoundShiftStamp2"); + } + + public static int divStamp1(int[] a) { + int v = a.length / 4; + return v & 0x80000000; + } + + public static int divStamp2(int[] a) { + int v = a.length / 5; + return v & 0x80000000; + } + + @Test + public void testDiv() { + testZeroReturn("divStamp1"); + testZeroReturn("divStamp2"); + } + + public static int distinctMask(int a, int b) { + int x = a & 0xaaaa; + int y = (b & 0x5555) | 0x1; + return x == y ? 1 : 0; + } + + @Test + public void testDistinctMask() { + testZeroReturn("distinctMask"); + } + + private void testZeroReturn(String methodName) { + StructuredGraph graph = parseEager(methodName, AllowAssumptions.YES); + new CanonicalizerPhase().apply(graph, new PhaseContext(getProviders())); + new DeadCodeEliminationPhase().apply(graph); + assertConstantReturn(graph, 0); + } +}