1 /* 2 * Copyright (c) 2003, 2010, 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 */ 24 25 #include "precompiled.hpp" 26 #include "oops/constMethodOop.hpp" 27 #include "oops/methodOop.hpp" 28 29 // Static initialization 30 const u2 constMethodOopDesc::MAX_IDNUM = 0xFFFE; 31 const u2 constMethodOopDesc::UNSET_IDNUM = 0xFFFF; 32 33 // How big must this constMethodObject be? 34 35 int constMethodOopDesc::object_size(int code_size, 36 int compressed_line_number_size, 37 int local_variable_table_length, 38 int checked_exceptions_length) { 39 int extra_bytes = code_size; 40 if (compressed_line_number_size > 0) { 41 extra_bytes += compressed_line_number_size; 42 } 43 if (checked_exceptions_length > 0) { 44 extra_bytes += sizeof(u2); 45 extra_bytes += checked_exceptions_length * sizeof(CheckedExceptionElement); 46 } 47 if (local_variable_table_length > 0) { 48 extra_bytes += sizeof(u2); 49 extra_bytes += 50 local_variable_table_length * sizeof(LocalVariableTableElement); 51 } 52 int extra_words = align_size_up(extra_bytes, BytesPerWord) / BytesPerWord; 53 return align_object_size(header_size() + extra_words); 54 } 55 56 57 // linenumber table - note that length is unknown until decompression, 58 // see class CompressedLineNumberReadStream. 59 60 u_char* constMethodOopDesc::compressed_linenumber_table() const { 61 // Located immediately following the bytecodes. 62 assert(has_linenumber_table(), "called only if table is present"); 63 return code_end(); 64 } 65 66 u2* constMethodOopDesc::checked_exceptions_length_addr() const { 67 // Located at the end of the constMethod. 68 assert(has_checked_exceptions(), "called only if table is present"); 69 return last_u2_element(); 70 } 71 72 u2* constMethodOopDesc::localvariable_table_length_addr() const { 73 assert(has_localvariable_table(), "called only if table is present"); 74 if (has_checked_exceptions()) { 75 // If checked_exception present, locate immediately before them. 76 return (u2*) checked_exceptions_start() - 1; 77 } else { 78 // Else, the linenumber table is at the end of the constMethod. 79 return last_u2_element(); 80 } 81 } 82 83 84 // Update the flags to indicate the presence of these optional fields. 85 void constMethodOopDesc::set_inlined_tables_length( 86 int checked_exceptions_len, 87 int compressed_line_number_size, 88 int localvariable_table_len) { 89 // Must be done in the order below, otherwise length_addr accessors 90 // will not work. Only set bit in header if length is positive. 91 assert(_flags == 0, "Error"); 92 if (compressed_line_number_size > 0) { 93 _flags |= _has_linenumber_table; 94 } 95 if (checked_exceptions_len > 0) { 96 _flags |= _has_checked_exceptions; 97 *(checked_exceptions_length_addr()) = checked_exceptions_len; 98 } 99 if (localvariable_table_len > 0) { 100 _flags |= _has_localvariable_table; 101 *(localvariable_table_length_addr()) = localvariable_table_len; 102 } 103 } 104 105 106 int constMethodOopDesc::checked_exceptions_length() const { 107 return has_checked_exceptions() ? *(checked_exceptions_length_addr()) : 0; 108 } 109 110 111 CheckedExceptionElement* constMethodOopDesc::checked_exceptions_start() const { 112 u2* addr = checked_exceptions_length_addr(); 113 u2 length = *addr; 114 assert(length > 0, "should only be called if table is present"); 115 addr -= length * sizeof(CheckedExceptionElement) / sizeof(u2); 116 return (CheckedExceptionElement*) addr; 117 } 118 119 120 int constMethodOopDesc::localvariable_table_length() const { 121 return has_localvariable_table() ? *(localvariable_table_length_addr()) : 0; 122 } 123 124 125 LocalVariableTableElement* constMethodOopDesc::localvariable_table_start() const { 126 u2* addr = localvariable_table_length_addr(); 127 u2 length = *addr; 128 assert(length > 0, "should only be called if table is present"); 129 addr -= length * sizeof(LocalVariableTableElement) / sizeof(u2); 130 return (LocalVariableTableElement*) addr; 131 }