1 /* 2 * Copyright (c) 2013, 2014, 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 jdk.vm.ci.code; 24 25 import java.util.*; 26 27 /** 28 * A map from registers to frame slots. This can be used to describe where callee saved registers 29 * are saved in a callee's frame. 30 */ 31 public final class RegisterSaveLayout { 32 33 /** 34 * Keys. 35 */ 36 private final Register[] registers; 37 38 /** 39 * Slot indexes relative to stack pointer. 40 */ 41 private final int[] slots; 42 43 /** 44 * Creates a map from registers to frame slots. 45 * 46 * @param registers the keys in the map 47 * @param slots frame slot index for each register in {@code registers} 48 */ 49 public RegisterSaveLayout(Register[] registers, int[] slots) { 50 assert registers.length == slots.length; 51 this.registers = registers; 52 this.slots = slots; 53 assert registersToSlots(false).size() == registers.length : "non-unique registers"; 54 assert new HashSet<>(registersToSlots(false).values()).size() == slots.length : "non-unqiue slots"; 55 } 56 57 /** 58 * Gets the frame slot index for a given register. 59 * 60 * @param register register to get the frame slot index for 61 * @return frame slot index 62 */ 63 public int registerToSlot(Register register) { 64 for (int i = 0; i < registers.length; i++) { 65 if (register.equals(registers[i])) { 66 return slots[i]; 67 } 68 } 69 throw new IllegalArgumentException(register + " not saved by this layout: " + this); 70 } 71 72 /** 73 * Gets this layout information as a {@link Map} from registers to slots. 74 */ 75 public Map<Register, Integer> registersToSlots(boolean sorted) { 76 Map<Register, Integer> result; 77 if (sorted) { 78 result = new TreeMap<>(); 79 } else { 80 result = new HashMap<>(); 81 } 82 for (int i = 0; i < registers.length; i++) { 83 result.put(registers[i], slots[i]); 84 } 85 return result; 86 } 87 88 /** 89 * Gets this layout information as a {@link Map} from slots to registers. 90 */ 91 public Map<Integer, Register> slotsToRegisters(boolean sorted) { 92 Map<Integer, Register> result; 93 if (sorted) { 94 result = new TreeMap<>(); 95 } else { 96 result = new HashMap<>(); 97 } 98 for (int i = 0; i < registers.length; i++) { 99 result.put(slots[i], registers[i]); 100 } 101 return result; 102 } 103 104 @Override 105 public int hashCode() { 106 throw new UnsupportedOperationException(); 107 } 108 109 @Override 110 public boolean equals(Object obj) { 111 if (this == obj) { 112 return true; 113 } 114 if (obj instanceof RegisterSaveLayout) { 115 RegisterSaveLayout that = (RegisterSaveLayout) obj; 116 if (Arrays.equals(registers, that.registers) && Arrays.equals(slots, that.slots)) { 117 return true; 118 } 119 } 120 return false; 121 } 122 123 @Override 124 public String toString() { 125 return registersToSlots(true).toString(); 126 } 127 }