Mercurial > hg > truffle
changeset 21220:e02ae54e6a44
Introduce c.o.g.lir.ssa.SSAUtils.
author | Josef Eisl <josef.eisl@jku.at> |
---|---|
date | Wed, 22 Apr 2015 11:40:17 +0200 |
parents | a4d68add31f6 |
children | da2b2d3edeeb |
files | graal/com.oracle.graal.lir/src/com/oracle/graal/lir/ssa/SSADestructionPhase.java graal/com.oracle.graal.lir/src/com/oracle/graal/lir/ssa/SSAUtils.java |
diffstat | 2 files changed, 108 insertions(+), 24 deletions(-) [+] |
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--- a/graal/com.oracle.graal.lir/src/com/oracle/graal/lir/ssa/SSADestructionPhase.java Mon Apr 20 16:02:38 2015 +0200 +++ b/graal/com.oracle.graal.lir/src/com/oracle/graal/lir/ssa/SSADestructionPhase.java Wed Apr 22 11:40:17 2015 +0200 @@ -25,7 +25,6 @@ import java.util.*; import com.oracle.graal.api.code.*; -import com.oracle.graal.api.meta.*; import com.oracle.graal.compiler.common.cfg.*; import com.oracle.graal.lir.*; import com.oracle.graal.lir.StandardOp.JumpOp; @@ -41,43 +40,26 @@ AbstractControlFlowGraph<?> cfg = lir.getControlFlowGraph(); for (AbstractBlockBase<?> block : cfg.getBlocks()) { doBlock(block, lir, lirGen); - } - } private static void doBlock(AbstractBlockBase<?> block, LIR lir, LIRGeneratorTool lirGen) { if (block.getPredecessorCount() > 1) { LabelOp label = (LabelOp) lir.getLIRforBlock(block).get(0); for (AbstractBlockBase<?> pred : block.getPredecessors()) { - assert pred.getSuccessorCount() == 1 : String.format("Merge predecessor block %s has more than one successor? %s", pred, pred.getSuccessors()); List<LIRInstruction> instructions = lir.getLIRforBlock(pred); - JumpOp jump = (JumpOp) instructions.get(instructions.size() - 1); + int insertBefore = instructions.size() - 1; + JumpOp jump = (JumpOp) instructions.get(insertBefore); - resolvePhi(label, jump, lirGen, instructions); + PhiResolver resolver = PhiResolver.create(lirGen, new LIRInsertionBuffer(), instructions, insertBefore); + SSAUtils.forEachPhiValuePair(lir, block, pred, resolver::move); + resolver.dispose(); + jump.clearOutgoingValues(); } label.clearIncomingValues(); } } - private static void resolvePhi(LabelOp label, JumpOp jump, LIRGeneratorTool gen, List<LIRInstruction> instructions) { - int incomingSize = label.getIncomingSize(); - int outgoingSize = jump.getOutgoingSize(); - assert incomingSize == outgoingSize : String.format("Phi In/Out size mismatch: in=%d vs. out=%d", incomingSize, outgoingSize); - - int insertBefore = instructions.size() - 1; - assert instructions.get(insertBefore) == jump; - - PhiResolver resolver = PhiResolver.create(gen, new LIRInsertionBuffer(), instructions, insertBefore); - for (int i = 0; i < incomingSize; i++) { - Value phiIn = label.getIncomingValue(i); - Value phiOut = jump.getOutgoingValue(i); - resolver.move(phiIn, phiOut); - } - resolver.dispose(); - - } - }
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/graal/com.oracle.graal.lir/src/com/oracle/graal/lir/ssa/SSAUtils.java Wed Apr 22 11:40:17 2015 +0200 @@ -0,0 +1,102 @@ +/* + * 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 com.oracle.graal.lir.ssa; + +import java.util.*; + +import com.oracle.graal.api.meta.*; +import com.oracle.graal.compiler.common.cfg.*; +import com.oracle.graal.lir.*; +import com.oracle.graal.lir.StandardOp.BlockEndOp; +import com.oracle.graal.lir.StandardOp.JumpOp; +import com.oracle.graal.lir.StandardOp.LabelOp; + +/** + * Utilities for working with Static-Single-Assignment LIR form. + * + * <h2>Representation of <code>PHI</code>s</h2> + * + * There is no explicit <code>PHI</code> {@linkplain LIRInstruction}. Instead, they are implemented + * as parallel copy that span across a control-flow edge. + * + * The variables introduced by <code>PHI</code>s of a specific {@linkplain AbstractBlockBase merge + * block} are {@linkplain LabelOp#setIncomingValues attached} to the {@linkplain LabelOp} of the + * block. The outgoing values from the predecessor are {@link JumpOp#setOutgoingValues input} to the + * {@linkplain BlockEndOp} of the predecessor. Because there are no critical edges we know that the + * {@link BlockEndOp} of the predecessor has to be a {@link JumpOp}. + * + * <h3>Example:</h3> + * + * <pre> + * B0 -> B1 + * ... + * v0|i = ... + * JUMP ~[v0|i, int[0|0x0]] destination: B0 -> B1 + * ________________________________________________ + * + * B2 -> B1 + * ... + * v1|i = ... + * v2|i = ... + * JUMP ~[v1|i, v2|i] destination: B2 -> B1 + * ________________________________________________ + * + * B1 <- B0,B2 + * [v3|i, v4|i] = LABEL + * ... + * </pre> + */ +public final class SSAUtils { + + public interface PhiValueVisitor { + /** + * @param phiIn the incoming value at the merge block + * @param phiOut the outgoing value from the predecessor block + */ + void visit(Value phiIn, Value phiOut); + } + + /** + * Visits each phi value pair of an edge, i.e. the outgoing value from the predecessor and the + * incoming value to the merge block. + */ + public static void forEachPhiValuePair(LIR lir, AbstractBlockBase<?> merge, AbstractBlockBase<?> pred, PhiValueVisitor visitor) { + if (merge.getPredecessorCount() < 2) { + return; + } + assert merge.getPredecessors().contains(pred) : String.format("%s not in predecessor list: %s", pred, merge.getPredecessors()); + assert pred.getSuccessorCount() == 1 : String.format("Merge predecessor block %s has more than one successor? %s", pred, pred.getSuccessors()); + assert pred.getSuccessors().get(0) == merge : String.format("Predecessor block %s has wrong successor: %s, should be: %s", pred, pred.getSuccessors().get(0), merge); + + List<LIRInstruction> instructions = lir.getLIRforBlock(pred); + JumpOp jump = (JumpOp) instructions.get(instructions.size() - 1); + LabelOp label = (LabelOp) lir.getLIRforBlock(merge).get(0); + + assert label.getIncomingSize() == jump.getOutgoingSize() : String.format("Phi In/Out size mismatch: in=%d vs. out=%d", label.getIncomingSize(), jump.getOutgoingSize()); + + for (int i = 0; i < label.getIncomingSize(); i++) { + visitor.visit(label.getIncomingValue(i), jump.getOutgoingValue(i)); + } + } + +}