1 /*
   2  * Copyright (c) 2014, 2015, 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.hotspot.nodes.type;
  24 
  25 import jdk.vm.ci.hotspot.HotSpotMetaspaceConstant;
  26 import jdk.vm.ci.meta.Constant;
  27 import jdk.vm.ci.meta.JavaConstant;
  28 import jdk.vm.ci.meta.MemoryAccessProvider;
  29 import jdk.vm.ci.meta.MetaAccessProvider;
  30 
  31 import org.graalvm.compiler.core.common.type.AbstractPointerStamp;
  32 import org.graalvm.compiler.core.common.type.Stamp;
  33 
  34 public final class MethodCountersPointerStamp extends MetaspacePointerStamp {
  35 
  36     private static final MethodCountersPointerStamp METHOD_COUNTERS = new MethodCountersPointerStamp(false, false);
  37 
  38     private static final MethodCountersPointerStamp METHOD_COUNTERS_NON_NULL = new MethodCountersPointerStamp(true, false);
  39 
  40     private static final MethodCountersPointerStamp METHOD_COUNTERS_ALWAYS_NULL = new MethodCountersPointerStamp(false, true);
  41 
  42     public static MethodCountersPointerStamp methodCounters() {
  43         return METHOD_COUNTERS;
  44     }
  45 
  46     public static MethodCountersPointerStamp methodCountersNonNull() {
  47         return METHOD_COUNTERS_NON_NULL;
  48     }
  49 
  50     private MethodCountersPointerStamp(boolean nonNull, boolean alwaysNull) {
  51         super(nonNull, alwaysNull);
  52     }
  53 
  54     @Override
  55     protected AbstractPointerStamp copyWith(boolean newNonNull, boolean newAlwaysNull) {
  56         if (newNonNull) {
  57             assert !newAlwaysNull;
  58             return METHOD_COUNTERS_NON_NULL;
  59         } else if (newAlwaysNull) {
  60             return METHOD_COUNTERS_ALWAYS_NULL;
  61         } else {
  62             return METHOD_COUNTERS;
  63         }
  64     }
  65 
  66     @Override
  67     public boolean isCompatible(Stamp otherStamp) {
  68         if (this == otherStamp) {
  69             return true;
  70         }
  71         return otherStamp instanceof MethodCountersPointerStamp;
  72     }
  73 
  74     @Override
  75     public Stamp constant(Constant c, MetaAccessProvider meta) {
  76         if (JavaConstant.NULL_POINTER.equals(c)) {
  77             return METHOD_COUNTERS_ALWAYS_NULL;
  78         } else {
  79             assert c instanceof HotSpotMetaspaceConstant;
  80             return METHOD_COUNTERS_NON_NULL;
  81         }
  82     }
  83 
  84     @Override
  85     public Constant readConstant(MemoryAccessProvider provider, Constant base, long displacement) {
  86         return null;
  87     }
  88 
  89     @Override
  90     public String toString() {
  91         StringBuilder ret = new StringBuilder("MethodCounters*");
  92         appendString(ret);
  93         return ret.toString();
  94     }
  95 }