Tue, 26 Jun 2012 19:08:44 -0400
7178145: Change constMethodOop::_exception_table to optionally inlined u2 table.
Summary: Change constMethodOop::_exception_table to optionally inlined u2 table.
Reviewed-by: bdelsart, coleenp, kamg
1 /*
2 * Copyright (c) 2003, 2012, 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
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7 * published by the Free Software Foundation.
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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.
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19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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23 */
25 #include "precompiled.hpp"
26 #include "oops/constMethodOop.hpp"
27 #include "oops/methodOop.hpp"
29 // Static initialization
30 const u2 constMethodOopDesc::MAX_IDNUM = 0xFFFE;
31 const u2 constMethodOopDesc::UNSET_IDNUM = 0xFFFF;
33 // How big must this constMethodObject be?
35 int constMethodOopDesc::object_size(int code_size,
36 int compressed_line_number_size,
37 int local_variable_table_length,
38 int exception_table_length,
39 int checked_exceptions_length) {
40 int extra_bytes = code_size;
41 if (compressed_line_number_size > 0) {
42 extra_bytes += compressed_line_number_size;
43 }
44 if (checked_exceptions_length > 0) {
45 extra_bytes += sizeof(u2);
46 extra_bytes += checked_exceptions_length * sizeof(CheckedExceptionElement);
47 }
48 if (local_variable_table_length > 0) {
49 extra_bytes += sizeof(u2);
50 extra_bytes +=
51 local_variable_table_length * sizeof(LocalVariableTableElement);
52 }
53 if (exception_table_length > 0) {
54 extra_bytes += sizeof(u2);
55 extra_bytes += exception_table_length * sizeof(ExceptionTableElement);
56 }
57 int extra_words = align_size_up(extra_bytes, BytesPerWord) / BytesPerWord;
58 return align_object_size(header_size() + extra_words);
59 }
61 methodOop constMethodOopDesc::method() const {
62 return instanceKlass::cast(_constants->pool_holder())->method_with_idnum(
63 _method_idnum);
64 }
66 // linenumber table - note that length is unknown until decompression,
67 // see class CompressedLineNumberReadStream.
69 u_char* constMethodOopDesc::compressed_linenumber_table() const {
70 // Located immediately following the bytecodes.
71 assert(has_linenumber_table(), "called only if table is present");
72 return code_end();
73 }
75 u2* constMethodOopDesc::checked_exceptions_length_addr() const {
76 // Located at the end of the constMethod.
77 assert(has_checked_exceptions(), "called only if table is present");
78 return last_u2_element();
79 }
81 u2* constMethodOopDesc::exception_table_length_addr() const {
82 assert(has_exception_handler(), "called only if table is present");
83 if (has_checked_exceptions()) {
84 // If checked_exception present, locate immediately before them.
85 return (u2*) checked_exceptions_start() - 1;
86 } else {
87 // Else, the exception table is at the end of the constMethod.
88 return last_u2_element();
89 }
90 }
92 u2* constMethodOopDesc::localvariable_table_length_addr() const {
93 assert(has_localvariable_table(), "called only if table is present");
94 if (has_exception_handler()) {
95 // If exception_table present, locate immediately before them.
96 return (u2*) exception_table_start() - 1;
97 } else {
98 if (has_checked_exceptions()) {
99 // If checked_exception present, locate immediately before them.
100 return (u2*) checked_exceptions_start() - 1;
101 } else {
102 // Else, the linenumber table is at the end of the constMethod.
103 return last_u2_element();
104 }
105 }
106 }
109 // Update the flags to indicate the presence of these optional fields.
110 void constMethodOopDesc::set_inlined_tables_length(
111 int checked_exceptions_len,
112 int compressed_line_number_size,
113 int localvariable_table_len,
114 int exception_table_len) {
115 // Must be done in the order below, otherwise length_addr accessors
116 // will not work. Only set bit in header if length is positive.
117 assert(_flags == 0, "Error");
118 if (compressed_line_number_size > 0) {
119 _flags |= _has_linenumber_table;
120 }
121 if (checked_exceptions_len > 0) {
122 _flags |= _has_checked_exceptions;
123 *(checked_exceptions_length_addr()) = checked_exceptions_len;
124 }
125 if (exception_table_len > 0) {
126 _flags |= _has_exception_table;
127 *(exception_table_length_addr()) = exception_table_len;
128 }
129 if (localvariable_table_len > 0) {
130 _flags |= _has_localvariable_table;
131 *(localvariable_table_length_addr()) = localvariable_table_len;
132 }
133 }
136 int constMethodOopDesc::checked_exceptions_length() const {
137 return has_checked_exceptions() ? *(checked_exceptions_length_addr()) : 0;
138 }
141 CheckedExceptionElement* constMethodOopDesc::checked_exceptions_start() const {
142 u2* addr = checked_exceptions_length_addr();
143 u2 length = *addr;
144 assert(length > 0, "should only be called if table is present");
145 addr -= length * sizeof(CheckedExceptionElement) / sizeof(u2);
146 return (CheckedExceptionElement*) addr;
147 }
150 int constMethodOopDesc::localvariable_table_length() const {
151 return has_localvariable_table() ? *(localvariable_table_length_addr()) : 0;
152 }
155 LocalVariableTableElement* constMethodOopDesc::localvariable_table_start() const {
156 u2* addr = localvariable_table_length_addr();
157 u2 length = *addr;
158 assert(length > 0, "should only be called if table is present");
159 addr -= length * sizeof(LocalVariableTableElement) / sizeof(u2);
160 return (LocalVariableTableElement*) addr;
161 }
163 int constMethodOopDesc::exception_table_length() const {
164 return has_exception_handler() ? *(exception_table_length_addr()) : 0;
165 }
167 ExceptionTableElement* constMethodOopDesc::exception_table_start() const {
168 u2* addr = exception_table_length_addr();
169 u2 length = *addr;
170 assert(length > 0, "should only be called if table is present");
171 addr -= length * sizeof(ExceptionTableElement) / sizeof(u2);
172 return (ExceptionTableElement*)addr;
173 }