001/* 002 * Copyright (c) 2012, 2015, Oracle and/or its affiliates. All rights reserved. 003 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 004 * 005 * This code is free software; you can redistribute it and/or modify it 006 * under the terms of the GNU General Public License version 2 only, as 007 * published by the Free Software Foundation. 008 * 009 * This code is distributed in the hope that it will be useful, but WITHOUT 010 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 011 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 012 * version 2 for more details (a copy is included in the LICENSE file that 013 * accompanied this code). 014 * 015 * You should have received a copy of the GNU General Public License version 016 * 2 along with this work; if not, write to the Free Software Foundation, 017 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 018 * 019 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 020 * or visit www.oracle.com if you need additional information or have any 021 * questions. 022 */ 023package com.oracle.graal.compiler.common.type; 024 025import jdk.internal.jvmci.common.*; 026import jdk.internal.jvmci.meta.*; 027 028import com.oracle.graal.compiler.common.spi.*; 029 030/** 031 * This stamp represents the type of the {@link Kind#Illegal} value in the second slot of 032 * {@link Kind#Long} and {@link Kind#Double} values. It can only appear in framestates or virtual 033 * objects. 034 */ 035public final class IllegalStamp extends Stamp { 036 037 private IllegalStamp() { 038 } 039 040 @Override 041 public Kind getStackKind() { 042 return Kind.Illegal; 043 } 044 045 @Override 046 public LIRKind getLIRKind(LIRKindTool tool) { 047 throw JVMCIError.shouldNotReachHere("illegal stamp should not reach backend"); 048 } 049 050 @Override 051 public Stamp unrestricted() { 052 return this; 053 } 054 055 @Override 056 public Stamp empty() { 057 return this; 058 } 059 060 @Override 061 public Stamp constant(Constant c, MetaAccessProvider meta) { 062 assert ((PrimitiveConstant) c).getKind() == Kind.Illegal; 063 return this; 064 } 065 066 @Override 067 public ResolvedJavaType javaType(MetaAccessProvider metaAccess) { 068 throw JVMCIError.shouldNotReachHere("illegal stamp has no Java type"); 069 } 070 071 @Override 072 public Stamp meet(Stamp other) { 073 assert other instanceof IllegalStamp; 074 return this; 075 } 076 077 @Override 078 public Stamp join(Stamp other) { 079 assert other instanceof IllegalStamp; 080 return this; 081 } 082 083 @Override 084 public boolean isCompatible(Stamp stamp) { 085 return stamp instanceof IllegalStamp; 086 } 087 088 @Override 089 public String toString() { 090 return "ILLEGAL"; 091 } 092 093 @Override 094 public boolean hasValues() { 095 return true; 096 } 097 098 @Override 099 public Stamp improveWith(Stamp other) { 100 assert other instanceof IllegalStamp; 101 return this; 102 } 103 104 @Override 105 public Constant readConstant(MemoryAccessProvider provider, Constant base, long displacement) { 106 throw JVMCIError.shouldNotReachHere("can't read values of illegal stamp"); 107 } 108 109 private static final IllegalStamp instance = new IllegalStamp(); 110 111 static IllegalStamp getInstance() { 112 return instance; 113 } 114}