Mercurial > hg > graal-compiler
view graal/com.oracle.jvmci.meta/src/com/oracle/jvmci/meta/LIRKind.java @ 21591:6c5327245831
LinearScan: fix intervals context.
author | Josef Eisl <josef.eisl@jku.at> |
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date | Fri, 29 May 2015 10:59:03 +0200 |
parents | 48c1ebd24120 |
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/* * Copyright (c) 2014, 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.jvmci.meta; import java.util.*; /** * Represents the type of values in the LIR. It is composed of a {@link PlatformKind} that gives the * low level representation of the value, and a {@link #referenceMask} that describes the location * of object references in the value. * * <h2>Constructing {@link LIRKind} instances</h2> * * During LIR generation, every new {@link Value} should get a {@link LIRKind} of the correct * {@link PlatformKind} that also contains the correct reference information. {@linkplain LIRKind * LIRKinds} should be created as follows: * * <p> * If the result value is created from one or more input values, the {@link LIRKind} should be * created with {@link LIRKind#derive}(inputs). If the result has a different {@link PlatformKind} * than the inputs, {@link LIRKind#derive}(inputs).{@link #changeType}(resultKind) should be used. * <p> * If the result is an exact copy of one of the inputs, {@link Value#getLIRKind()} can be used. Note * that this is only correct for move-like operations, like conditional move or compare-and-swap. * For convert operations, {@link LIRKind#derive} should be used. * <p> * If it is known that the result will be a reference (e.g. pointer arithmetic where the end result * is a valid oop), {@link LIRKind#reference} should be used. * <p> * If it is known that the result will neither be a reference nor be derived from a reference, * {@link LIRKind#value} can be used. If the operation producing this value has inputs, this is very * likely wrong, and {@link LIRKind#derive} should be used instead. * <p> * If it is known that the result is derived from a reference, {@link LIRKind#derivedReference} can * be used. In most cases, {@link LIRKind#derive} should be used instead, since it is able to detect * this automatically. */ public final class LIRKind { /** * The non-type. This uses {@link #derivedReference}, so it can never be part of an oop map. */ public static final LIRKind Illegal = derivedReference(Kind.Illegal); private final PlatformKind platformKind; private final int referenceMask; private static final int DERIVED_REFERENCE = -1; private LIRKind(PlatformKind platformKind, int referenceMask) { this.platformKind = platformKind; this.referenceMask = referenceMask; } /** * Create a {@link LIRKind} of type {@code platformKind} that contains a primitive value. Should * be only used when it's guaranteed that the value is not even indirectly derived from a * reference. Otherwise, {@link #derive(Value...)} should be used instead. */ public static LIRKind value(PlatformKind platformKind) { assert platformKind != Kind.Object : "Object should always be used as reference type"; return new LIRKind(platformKind, 0); } /** * Create a {@link LIRKind} of type {@code platformKind} that contains a single tracked oop * reference. */ public static LIRKind reference(PlatformKind platformKind) { int length = platformKind.getVectorLength(); assert 0 < length && length < 32 : "vector of " + length + " references not supported"; return new LIRKind(platformKind, (1 << length) - 1); } /** * Create a {@link LIRKind} of type {@code platformKind} that contains a value that is derived * from a reference. Values of this {@link LIRKind} can not be live at safepoints. In most * cases, this should not be called directly. {@link #derive} should be used instead to * automatically propagate this information. */ public static LIRKind derivedReference(PlatformKind platformKind) { return new LIRKind(platformKind, DERIVED_REFERENCE); } /** * Derive a new type from inputs. The result will have the {@link PlatformKind} of one of the * inputs. If all inputs are values, the result is a value. Otherwise, the result is a derived * reference. * * This method should be used to construct the result {@link LIRKind} of any operation that * modifies values (e.g. arithmetics). */ public static LIRKind derive(Value... inputs) { assert inputs.length > 0; for (Value input : inputs) { LIRKind kind = input.getLIRKind(); if (kind.isDerivedReference()) { return kind; } else if (!kind.isValue()) { return kind.makeDerivedReference(); } } // all inputs are values, just return one of them return inputs[0].getLIRKind(); } /** * Merge the types of the inputs. The result will have the {@link PlatformKind} of one of the * inputs. If all inputs are values (references), the result is a value (reference). Otherwise, * the result is a derived reference. * * This method should be used to construct the result {@link LIRKind} of merge operation that do * not modify values (e.g. phis). */ public static LIRKind merge(Value... inputs) { assert inputs.length > 0; ArrayList<LIRKind> kinds = new ArrayList<>(inputs.length); for (int i = 0; i < inputs.length; i++) { kinds.add(inputs[i].getLIRKind()); } return merge(kinds); } /** * @see #merge(Value...) */ public static LIRKind merge(Iterable<LIRKind> kinds) { LIRKind mergeKind = null; for (LIRKind kind : kinds) { assert mergeKind == null || verifyMoveKinds(mergeKind, kind) : String.format("Input kinds do not match %s vs. %s", mergeKind, kind); if (kind.isDerivedReference()) { /** * Kind is a derived reference therefore the result can only be also a derived * reference. */ return kind; } if (mergeKind == null) { mergeKind = kind; continue; } if (kind.isValue()) { /* Kind is a value. */ if (mergeKind.referenceMask != 0) { /* * Inputs consists of values and references. Make the result a derived * reference. */ return mergeKind.makeDerivedReference(); } /* Check that other inputs are also values. */ } else { /* Kind is a reference. */ if (mergeKind.referenceMask != kind.referenceMask) { /* * Reference maps do not match so the result can only be a derived reference. */ return mergeKind.makeDerivedReference(); } } } assert mergeKind != null; // all inputs are values or references, just return one of them return mergeKind; } /** * Create a new {@link LIRKind} with the same reference information and a new * {@linkplain #getPlatformKind platform kind}. If the new kind is a longer vector than this, * the new elements are marked as untracked values. */ public LIRKind changeType(PlatformKind newPlatformKind) { if (newPlatformKind == platformKind) { return this; } else if (isDerivedReference()) { return derivedReference(newPlatformKind); } else if (referenceMask == 0) { // value type return new LIRKind(newPlatformKind, 0); } else { // reference type int newLength = Math.min(32, newPlatformKind.getVectorLength()); int newReferenceMask = referenceMask & (0xFFFFFFFF >>> (32 - newLength)); assert newReferenceMask != DERIVED_REFERENCE; return new LIRKind(newPlatformKind, newReferenceMask); } } /** * Create a new {@link LIRKind} with a new {@linkplain #getPlatformKind platform kind}. If the * new kind is longer than this, the reference positions are repeated to fill the vector. */ public LIRKind repeat(PlatformKind newPlatformKind) { if (isDerivedReference()) { return derivedReference(newPlatformKind); } else if (referenceMask == 0) { // value type return new LIRKind(newPlatformKind, 0); } else { // reference type int oldLength = platformKind.getVectorLength(); int newLength = newPlatformKind.getVectorLength(); assert oldLength <= newLength && newLength < 32 && (newLength % oldLength) == 0; // repeat reference mask to fill new kind int newReferenceMask = 0; for (int i = 0; i < newLength; i += platformKind.getVectorLength()) { newReferenceMask |= referenceMask << i; } assert newReferenceMask != DERIVED_REFERENCE; return new LIRKind(newPlatformKind, newReferenceMask); } } /** * Create a new {@link LIRKind} with the same type, but marked as containing a derivedReference. */ public LIRKind makeDerivedReference() { return new LIRKind(platformKind, DERIVED_REFERENCE); } /** * Get the low level type that is used in code generation. */ public PlatformKind getPlatformKind() { return platformKind; } /** * Check whether this value is derived from a reference. If this returns {@code true}, this * value must not be live at safepoints. */ public boolean isDerivedReference() { return referenceMask == DERIVED_REFERENCE; } /** * Check whether the {@code idx}th part of this value is a reference that must be tracked at * safepoints. * * @param idx The index into the vector if this is a vector kind. Must be 0 if this is a scalar * kind. */ public boolean isReference(int idx) { assert 0 <= idx && idx < platformKind.getVectorLength() : "invalid index " + idx + " in " + this; return !isDerivedReference() && (referenceMask & 1 << idx) != 0; } /** * Check whether this kind is a value type that doesn't need to be tracked at safepoints. */ public boolean isValue() { return referenceMask == 0; } @Override public String toString() { if (isValue()) { return platformKind.name(); } else if (isDerivedReference()) { return platformKind.name() + "[*]"; } else { StringBuilder ret = new StringBuilder(); ret.append(platformKind.name()); ret.append('['); for (int i = 0; i < platformKind.getVectorLength(); i++) { if (isReference(i)) { ret.append('.'); } else { ret.append(' '); } } ret.append(']'); return ret.toString(); } } @Override public int hashCode() { final int prime = 31; int result = 1; result = prime * result + ((platformKind == null) ? 0 : platformKind.hashCode()); result = prime * result + referenceMask; return result; } @Override public boolean equals(Object obj) { if (this == obj) { return true; } if (!(obj instanceof LIRKind)) { return false; } LIRKind other = (LIRKind) obj; return platformKind == other.platformKind && referenceMask == other.referenceMask; } public static boolean verifyMoveKinds(LIRKind dst, LIRKind src) { if (src.equals(dst)) { return true; } /* * TODO(je,rs) What we actually want is toStackKind(src.getPlatformKind()).equals( * dst.getPlatformKind()) but due to the handling of sub-integer at the current point * (phi-)moves from e.g. integer to short can happen. Therefore we compare stack kinds. */ if (toStackKind(src.getPlatformKind()).equals(toStackKind(dst.getPlatformKind()))) { return !src.isDerivedReference() || dst.isDerivedReference(); } return false; } private static PlatformKind toStackKind(PlatformKind platformKind) { if (platformKind instanceof Kind) { return ((Kind) platformKind).getStackKind(); } return platformKind; } }