| /* |
| * Copyright (c) 2009, 2011, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| package jdk.vm.ci.code; |
| |
| import java.util.Objects; |
| |
| import jdk.vm.ci.meta.ResolvedJavaMethod; |
| |
| /** |
| * Represents a code position, that is, a chain of inlined methods with bytecode locations, that is |
| * communicated from the compiler to the runtime system. A code position can be used by the runtime |
| * system to reconstruct a source-level stack trace for exceptions and to create |
| * {@linkplain BytecodeFrame frames} for deoptimization. |
| */ |
| public class BytecodePosition { |
| |
| private final BytecodePosition caller; |
| private final ResolvedJavaMethod method; |
| private final int bci; |
| |
| /** |
| * Constructs a new object representing a given parent/caller, a given method, and a given BCI. |
| * |
| * @param caller the parent position |
| * @param method the method |
| * @param bci a BCI within the method |
| */ |
| public BytecodePosition(BytecodePosition caller, ResolvedJavaMethod method, int bci) { |
| assert method != null; |
| this.caller = caller; |
| this.method = method; |
| this.bci = bci; |
| } |
| |
| /** |
| * Converts this code position to a string representation. |
| * |
| * @return a string representation of this code position |
| */ |
| @Override |
| public String toString() { |
| return CodeUtil.append(new StringBuilder(100), this).toString(); |
| } |
| |
| /** |
| * Deep equality test. |
| */ |
| @Override |
| public boolean equals(Object obj) { |
| if (obj == this) { |
| return true; |
| } |
| if (obj != null && getClass() == obj.getClass()) { |
| BytecodePosition that = (BytecodePosition) obj; |
| if (this.bci == that.bci && Objects.equals(this.getMethod(), that.getMethod()) && Objects.equals(this.caller, that.caller)) { |
| return true; |
| } |
| } |
| return false; |
| } |
| |
| @Override |
| public int hashCode() { |
| return getBCI(); |
| } |
| |
| /** |
| * @return The location within the method, as a bytecode index. The constant {@code -1} may be |
| * used to indicate the location is unknown, for example within code synthesized by the |
| * compiler. |
| */ |
| public int getBCI() { |
| return bci; |
| } |
| |
| /** |
| * @return The runtime interface method for this position. |
| */ |
| public ResolvedJavaMethod getMethod() { |
| return method; |
| } |
| |
| /** |
| * The position where this position has been called, {@code null} if none. |
| */ |
| public BytecodePosition getCaller() { |
| return caller; |
| } |
| |
| /** |
| * Adds a caller to the current position returning the new position. |
| */ |
| public BytecodePosition addCaller(BytecodePosition link) { |
| if (getCaller() == null) { |
| return new BytecodePosition(link, getMethod(), getBCI()); |
| } else { |
| return new BytecodePosition(getCaller().addCaller(link), getMethod(), getBCI()); |
| } |
| } |
| } |