1 /*

     2  * Copyright (c) 2011, 2016, Oracle and/or its affiliates. All rights reserved.

     3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

     4  *

     5  * This code is free software; you can redistribute it and/or modify it

     6  * under the terms of the GNU General Public License version 2 only, as

     7  * published by the Free Software Foundation.

     8  *

     9  * This code is distributed in the hope that it will be useful, but WITHOUT

    10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

    11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

    12  * version 2 for more details (a copy is included in the LICENSE file that

    13  * accompanied this code).

    14  *

    15  * You should have received a copy of the GNU General Public License version

    16  * 2 along with this work; if not, write to the Free Software Foundation,

    17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

    18  *

    19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

    20  * or visit www.oracle.com if you need additional information or have any

    21  * questions.

    22  */

    23 package org.graalvm.compiler.nodes.spi;

    24 

    25 import org.graalvm.compiler.graph.Node;

    26 import org.graalvm.compiler.nodes.ValueNode;

    27 import org.graalvm.compiler.nodes.memory.address.AddressNode;

    28 

    29 import jdk.vm.ci.meta.JavaKind;

    30 

    31 /**

    32  * Provides a capability for replacing a higher node with one or more lower level nodes.

    33  */

    34 public interface LoweringProvider {

    35 

    36     void lower(Node n, LoweringTool tool);

    37 

    38     /**

    39      * Reconstructs the array index from an address node that was created as a lowering of an

    40      * indexed access to an array.

    41      *

    42      * @param elementKind the {@link JavaKind} of the array elements

    43      * @param address an {@link AddressNode} pointing to an element in an array

    44      * @return a node that gives the index of the element

    45      */

    46     ValueNode reconstructArrayIndex(JavaKind elementKind, AddressNode address);

    47 

    48     /**

    49      * Indicates whether the target platform supports comparison of integers of a particular bit

    50      * width. This check is used by optimizations that might introduce subword compares.

    51      */

    52     default boolean supportSubwordCompare(int bits) {

    53         // most platforms only support 32 and 64 bit compares

    54         return bits >= 32;

    55     }

    56 }