| /* |
| * Copyright (c) 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.replacements; |
| |
| import static org.graalvm.compiler.replacements.SnippetTemplate.DEFAULT_REPLACER; |
| |
| import org.graalvm.compiler.api.replacements.Fold; |
| import org.graalvm.compiler.api.replacements.Fold.InjectedParameter; |
| import org.graalvm.compiler.api.replacements.Snippet; |
| import org.graalvm.compiler.api.replacements.Snippet.ConstantParameter; |
| import org.graalvm.compiler.api.replacements.SnippetReflectionProvider; |
| import org.graalvm.compiler.core.common.spi.ArrayOffsetProvider; |
| import org.graalvm.compiler.debug.DebugHandlersFactory; |
| import org.graalvm.compiler.nodes.StructuredGraph; |
| import org.graalvm.compiler.nodes.spi.LoweringTool; |
| import org.graalvm.compiler.options.OptionValues; |
| import org.graalvm.compiler.phases.util.Providers; |
| import org.graalvm.compiler.replacements.SnippetTemplate.AbstractTemplates; |
| import org.graalvm.compiler.replacements.SnippetTemplate.Arguments; |
| import org.graalvm.compiler.replacements.SnippetTemplate.SnippetInfo; |
| import org.graalvm.compiler.replacements.nodes.ExplodeLoopNode; |
| |
| import jdk.vm.ci.code.TargetDescription; |
| import jdk.vm.ci.meta.JavaKind; |
| |
| public class ConstantStringIndexOfSnippets implements Snippets { |
| public static class Templates extends AbstractTemplates { |
| |
| private final SnippetInfo indexOfConstant = snippet(ConstantStringIndexOfSnippets.class, "indexOfConstant"); |
| |
| public Templates(OptionValues options, Iterable<DebugHandlersFactory> factories, Providers providers, SnippetReflectionProvider snippetReflection, TargetDescription target) { |
| super(options, factories, providers, snippetReflection, target); |
| } |
| |
| public void lower(SnippetLowerableMemoryNode stringIndexOf, LoweringTool tool) { |
| StructuredGraph graph = stringIndexOf.graph(); |
| Arguments args = new Arguments(indexOfConstant, graph.getGuardsStage(), tool.getLoweringStage()); |
| args.add("source", stringIndexOf.getArgument(0)); |
| args.add("sourceOffset", stringIndexOf.getArgument(1)); |
| args.add("sourceCount", stringIndexOf.getArgument(2)); |
| args.addConst("target", stringIndexOf.getArgument(3)); |
| args.add("targetOffset", stringIndexOf.getArgument(4)); |
| args.add("targetCount", stringIndexOf.getArgument(5)); |
| args.add("origFromIndex", stringIndexOf.getArgument(6)); |
| char[] targetCharArray = snippetReflection.asObject(char[].class, stringIndexOf.getArgument(3).asJavaConstant()); |
| args.addConst("md2", md2(targetCharArray)); |
| args.addConst("cache", computeCache(targetCharArray)); |
| template(stringIndexOf, args).instantiate(providers.getMetaAccess(), stringIndexOf, DEFAULT_REPLACER, args); |
| } |
| } |
| |
| static int md2(char[] target) { |
| int c = target.length; |
| if (c == 0) { |
| return 0; |
| } |
| char lastChar = target[c - 1]; |
| int md2 = c; |
| for (int i = 0; i < c - 1; i++) { |
| if (target[i] == lastChar) { |
| md2 = (c - 1) - i; |
| } |
| } |
| return md2; |
| } |
| |
| static long computeCache(char[] s) { |
| int c = s.length; |
| int cache = 0; |
| int i; |
| for (i = 0; i < c - 1; i++) { |
| cache |= (1 << (s[i] & 63)); |
| } |
| return cache; |
| } |
| |
| @Fold |
| static int charArrayBaseOffset(@InjectedParameter ArrayOffsetProvider arrayOffsetProvider) { |
| return arrayOffsetProvider.arrayBaseOffset(JavaKind.Char); |
| } |
| |
| /** Marker value for the {@link InjectedParameter} injected parameter. */ |
| static final ArrayOffsetProvider INJECTED = null; |
| |
| @Snippet |
| public static int indexOfConstant(char[] source, int sourceOffset, int sourceCount, |
| @ConstantParameter char[] target, int targetOffset, int targetCount, |
| int origFromIndex, @ConstantParameter int md2, @ConstantParameter long cache) { |
| int fromIndex = origFromIndex; |
| if (fromIndex >= sourceCount) { |
| return (targetCount == 0 ? sourceCount : -1); |
| } |
| if (fromIndex < 0) { |
| fromIndex = 0; |
| } |
| if (targetCount == 0) { |
| return fromIndex; |
| } |
| |
| int targetCountLess1 = targetCount - 1; |
| int sourceEnd = sourceCount - targetCountLess1; |
| |
| long base = charArrayBaseOffset(INJECTED); |
| int lastChar = UnsafeAccess.UNSAFE.getChar(target, base + targetCountLess1 * 2); |
| |
| outer_loop: for (long i = sourceOffset + fromIndex; i < sourceEnd;) { |
| int src = UnsafeAccess.UNSAFE.getChar(source, base + (i + targetCountLess1) * 2); |
| if (src == lastChar) { |
| // With random strings and a 4-character alphabet, |
| // reverse matching at this point sets up 0.8% fewer |
| // frames, but (paradoxically) makes 0.3% more probes. |
| // Since those probes are nearer the lastChar probe, |
| // there is may be a net D$ win with reverse matching. |
| // But, reversing loop inhibits unroll of inner loop |
| // for unknown reason. So, does running outer loop from |
| // (sourceOffset - targetCountLess1) to (sourceOffset + sourceCount) |
| if (targetCount <= 8) { |
| ExplodeLoopNode.explodeLoop(); |
| } |
| for (long j = 0; j < targetCountLess1; j++) { |
| char sourceChar = UnsafeAccess.UNSAFE.getChar(source, base + (i + j) * 2); |
| if (UnsafeAccess.UNSAFE.getChar(target, base + (targetOffset + j) * 2) != sourceChar) { |
| if ((cache & (1 << sourceChar)) == 0) { |
| if (md2 < j + 1) { |
| i += j + 1; |
| continue outer_loop; |
| } |
| } |
| i += md2; |
| continue outer_loop; |
| } |
| } |
| return (int) (i - sourceOffset); |
| } |
| if ((cache & (1 << src)) == 0) { |
| i += targetCountLess1; |
| } |
| i++; |
| } |
| return -1; |
| } |
| } |