1 /*
   2  * Copyright (c) 2013, 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.api.replacements;
  24 
  25 import java.lang.annotation.ElementType;
  26 import java.lang.annotation.Retention;
  27 import java.lang.annotation.RetentionPolicy;
  28 import java.lang.annotation.Target;
  29 
  30 import jdk.vm.ci.meta.Signature;
  31 
  32 /**
  33  * Denotes a method whose body is used by a compiler as the substitute (or intrinsification) of
  34  * another method. The exact method used to do the substitution is compiler dependent but every
  35  * compiler should require substitute methods to be annotated with {@link MethodSubstitution}. In
  36  * addition, a compiler is recommended to implement {@link MethodSubstitutionRegistry} to advertise
  37  * the mechanism by which it supports registration of method substitutes.
  38  */
  39 @Retention(RetentionPolicy.RUNTIME)
  40 @Target(ElementType.METHOD)
  41 public @interface MethodSubstitution {
  42 
  43     /**
  44      * Gets the name of the original method.
  45      * <p>
  46      * If the default value is specified for this element, then the name of the original method is
  47      * same as the substitute method.
  48      */
  49     String value() default "";
  50 
  51     /**
  52      * Determines if the original method is static.
  53      */
  54     boolean isStatic() default true;
  55 
  56     /**
  57      * Gets the {@linkplain Signature#toMethodDescriptor signature} of the original method.
  58      * <p>
  59      * If the default value is specified for this element, then the signature of the original method
  60      * is the same as the substitute method.
  61      */
  62     String signature() default "";
  63 
  64     /**
  65      * Determines if the substitution is for a method that may not be part of the runtime. For
  66      * example, a method introduced in a later JDK version. Substitutions for such methods are
  67      * omitted if the original method cannot be found.
  68      */
  69     boolean optional() default false;
  70 }