| /* |
| * Copyright (c) 2015, 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 org.graalvm.compiler.lir.alloc.trace; |
| |
| import java.util.List; |
| |
| import org.graalvm.compiler.core.common.alloc.Trace; |
| import org.graalvm.compiler.core.common.alloc.TraceBuilderResult; |
| import org.graalvm.compiler.core.common.cfg.AbstractBlockBase; |
| import org.graalvm.compiler.lir.LIR; |
| import org.graalvm.compiler.lir.LIRInstruction; |
| import org.graalvm.compiler.lir.StandardOp.JumpOp; |
| import org.graalvm.compiler.lir.StandardOp.LabelOp; |
| |
| import jdk.vm.ci.meta.Value; |
| |
| public class TraceUtil { |
| |
| public static AbstractBlockBase<?> getBestTraceInterPredecessor(TraceBuilderResult traceResult, AbstractBlockBase<?> block) { |
| AbstractBlockBase<?> bestPred = null; |
| int bestTraceId = traceResult.getTraceForBlock(block).getId(); |
| for (AbstractBlockBase<?> pred : block.getPredecessors()) { |
| int predTraceId = traceResult.getTraceForBlock(pred).getId(); |
| if (predTraceId < bestTraceId) { |
| bestPred = pred; |
| bestTraceId = predTraceId; |
| } |
| } |
| return bestPred; |
| } |
| |
| public static boolean isShadowedRegisterValue(Value value) { |
| assert value != null; |
| return value instanceof ShadowedRegisterValue; |
| } |
| |
| public static ShadowedRegisterValue asShadowedRegisterValue(Value value) { |
| assert isShadowedRegisterValue(value); |
| return (ShadowedRegisterValue) value; |
| } |
| |
| public static boolean isTrivialTrace(LIR lir, Trace trace) { |
| if (trace.size() != 1) { |
| return false; |
| } |
| List<LIRInstruction> instructions = lir.getLIRforBlock(trace.getBlocks()[0]); |
| if (instructions.size() != 2) { |
| return false; |
| } |
| assert instructions.get(0) instanceof LabelOp : "First instruction not a LabelOp: " + instructions.get(0); |
| if (((LabelOp) instructions.get(0)).isPhiIn()) { |
| /* |
| * Merge blocks are in general not trivial block because variables defined by a PHI |
| * always need a location. If the outgoing value of the predecessor is a constant we |
| * need to find an appropriate location (register or stack). |
| * |
| * Note that this case should not happen in practice since the trace containing the |
| * merge block should also contain one of the predecessors. For non-standard trace |
| * builders (e.g. the single block trace builder) this is not the true, though. |
| */ |
| return false; |
| } |
| /* |
| * Now we need to check if the BlockEndOp has no special operand requirements (i.e. |
| * stack-slot, register). For now we just check for JumpOp because we know that it doesn't. |
| */ |
| return instructions.get(1) instanceof JumpOp; |
| } |
| } |