1 /* 2 * Copyright (c) 2000, 2016, 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/oop.inline.hpp" 27 #include "oops/symbol.hpp" 28 #include "prims/jvmtiRedefineClassesTrace.hpp" 29 #include "prims/methodComparator.hpp" 30 #include "runtime/handles.inline.hpp" 31 #include "utilities/globalDefinitions.hpp" 32 33 BytecodeStream *MethodComparator::_s_old; 34 BytecodeStream *MethodComparator::_s_new; 35 ConstantPool* MethodComparator::_old_cp; 36 ConstantPool* MethodComparator::_new_cp; 37 BciMap *MethodComparator::_bci_map; 38 GrowableArray<int> *MethodComparator::_fwd_jmps; 39 40 bool MethodComparator::methods_EMCP(Method* old_method, Method* new_method) { 41 if (old_method->code_size() != new_method->code_size()) 42 return false; 43 if (check_stack_and_locals_size(old_method, new_method) != 0) { 44 // RC_TRACE macro has an embedded ResourceMark 45 RC_TRACE(0x00800000, ("Methods %s non-comparable with diagnosis %d", 46 old_method->name()->as_C_string(), 47 check_stack_and_locals_size(old_method, new_method))); 48 return false; 49 } 50 51 _old_cp = old_method->constants(); 52 _new_cp = new_method->constants(); 53 BytecodeStream s_old(old_method); 54 BytecodeStream s_new(new_method); 55 _s_old = &s_old; 56 _s_new = &s_new; 57 Bytecodes::Code c_old, c_new; 58 59 while ((c_old = s_old.next()) >= 0) { 60 if ((c_new = s_new.next()) < 0 || c_old != c_new) 61 return false; 62 63 if (! args_same(c_old, c_new)) 64 return false; 65 } 66 return true; 67 } 68 69 bool MethodComparator::args_same(Bytecodes::Code c_old, Bytecodes::Code c_new) { 70 // BytecodeStream returns the correct standard Java bytecodes for various "fast" 71 // bytecode versions, so we don't have to bother about them here.. 72 switch (c_old) { 73 case Bytecodes::_new : // fall through 74 case Bytecodes::_anewarray : // fall through 75 case Bytecodes::_multianewarray : // fall through 76 case Bytecodes::_checkcast : // fall through 77 case Bytecodes::_instanceof : { 78 u2 cpi_old = _s_old->get_index_u2(); 79 u2 cpi_new = _s_new->get_index_u2(); 80 if ((_old_cp->klass_at_noresolve(cpi_old) != _new_cp->klass_at_noresolve(cpi_new))) 81 return false; 82 if (c_old == Bytecodes::_multianewarray && 83 *(jbyte*)(_s_old->bcp() + 3) != *(jbyte*)(_s_new->bcp() + 3)) 84 return false; 85 break; 86 } 87 88 case Bytecodes::_getstatic : // fall through 89 case Bytecodes::_putstatic : // fall through 90 case Bytecodes::_getfield : // fall through 91 case Bytecodes::_putfield : // fall through 92 case Bytecodes::_invokevirtual : // fall through 93 case Bytecodes::_invokespecial : // fall through 94 case Bytecodes::_invokestatic : // fall through 95 case Bytecodes::_invokeinterface : { 96 int cpci_old = _s_old->get_index_u2_cpcache(); 97 int cpci_new = _s_new->get_index_u2_cpcache(); 98 // Check if the names of classes, field/method names and signatures at these indexes 99 // are the same. Indices which are really into constantpool cache (rather than constant 100 // pool itself) are accepted by the constantpool query routines below. 101 if ((_old_cp->klass_ref_at_noresolve(cpci_old) != _new_cp->klass_ref_at_noresolve(cpci_new)) || 102 (_old_cp->name_ref_at(cpci_old) != _new_cp->name_ref_at(cpci_new)) || 103 (_old_cp->signature_ref_at(cpci_old) != _new_cp->signature_ref_at(cpci_new))) 104 return false; 105 break; 106 } 107 case Bytecodes::_invokedynamic: { 108 int cpci_old = _s_old->get_index_u4(); 109 int cpci_new = _s_new->get_index_u4(); 110 111 // Check if the names of classes, field/method names and signatures at these indexes 112 // are the same. Indices which are really into constantpool cache (rather than constant 113 // pool itself) are accepted by the constantpool query routines below. 114 if ((_old_cp->name_ref_at(cpci_old) != _new_cp->name_ref_at(cpci_new)) || 115 (_old_cp->signature_ref_at(cpci_old) != _new_cp->signature_ref_at(cpci_new))) 116 return false; 117 118 // Translate object indexes to constant pool cache indexes. 119 cpci_old = _old_cp->invokedynamic_cp_cache_index(cpci_old); 120 cpci_new = _new_cp->invokedynamic_cp_cache_index(cpci_new); 121 122 int cpi_old = _old_cp->cache()->entry_at(cpci_old)->constant_pool_index(); 123 int cpi_new = _new_cp->cache()->entry_at(cpci_new)->constant_pool_index(); 124 int bsm_old = _old_cp->invoke_dynamic_bootstrap_method_ref_index_at(cpi_old); 125 int bsm_new = _new_cp->invoke_dynamic_bootstrap_method_ref_index_at(cpi_new); 126 if (!pool_constants_same(bsm_old, bsm_new)) 127 return false; 128 int cnt_old = _old_cp->invoke_dynamic_argument_count_at(cpi_old); 129 int cnt_new = _new_cp->invoke_dynamic_argument_count_at(cpi_new); 130 if (cnt_old != cnt_new) 131 return false; 132 for (int arg_i = 0; arg_i < cnt_old; arg_i++) { 133 int idx_old = _old_cp->invoke_dynamic_argument_index_at(cpi_old, arg_i); 134 int idx_new = _new_cp->invoke_dynamic_argument_index_at(cpi_new, arg_i); 135 if (!pool_constants_same(idx_old, idx_new)) 136 return false; 137 } 138 break; 139 } 140 141 case Bytecodes::_ldc : // fall through 142 case Bytecodes::_ldc_w : { 143 Bytecode_loadconstant ldc_old(_s_old->method(), _s_old->bci()); 144 Bytecode_loadconstant ldc_new(_s_new->method(), _s_new->bci()); 145 int cpi_old = ldc_old.pool_index(); 146 int cpi_new = ldc_new.pool_index(); 147 if (!pool_constants_same(cpi_old, cpi_new)) 148 return false; 149 break; 150 } 151 152 case Bytecodes::_ldc2_w : { 153 u2 cpi_old = _s_old->get_index_u2(); 154 u2 cpi_new = _s_new->get_index_u2(); 155 constantTag tag_old = _old_cp->tag_at(cpi_old); 156 constantTag tag_new = _new_cp->tag_at(cpi_new); 157 if (tag_old.value() != tag_new.value()) 158 return false; 159 if (tag_old.is_long()) { 160 if (_old_cp->long_at(cpi_old) != _new_cp->long_at(cpi_new)) 161 return false; 162 } else { 163 // Use jlong_cast to compare the bits rather than numerical values. 164 // This makes a difference for NaN constants. 165 if (jlong_cast(_old_cp->double_at(cpi_old)) != jlong_cast(_new_cp->double_at(cpi_new))) 166 return false; 167 } 168 break; 169 } 170 171 case Bytecodes::_bipush : 172 if (_s_old->bcp()[1] != _s_new->bcp()[1]) 173 return false; 174 break; 175 176 case Bytecodes::_sipush : 177 if (_s_old->get_index_u2() != _s_new->get_index_u2()) 178 return false; 179 break; 180 181 case Bytecodes::_aload : // fall through 182 case Bytecodes::_astore : // fall through 183 case Bytecodes::_dload : // fall through 184 case Bytecodes::_dstore : // fall through 185 case Bytecodes::_fload : // fall through 186 case Bytecodes::_fstore : // fall through 187 case Bytecodes::_iload : // fall through 188 case Bytecodes::_istore : // fall through 189 case Bytecodes::_lload : // fall through 190 case Bytecodes::_lstore : // fall through 191 case Bytecodes::_ret : 192 if (_s_old->is_wide() != _s_new->is_wide()) 193 return false; 194 if (_s_old->get_index() != _s_new->get_index()) 195 return false; 196 break; 197 198 case Bytecodes::_goto : // fall through 199 case Bytecodes::_if_acmpeq : // fall through 200 case Bytecodes::_if_acmpne : // fall through 201 case Bytecodes::_if_icmpeq : // fall through 202 case Bytecodes::_if_icmpne : // fall through 203 case Bytecodes::_if_icmplt : // fall through 204 case Bytecodes::_if_icmpge : // fall through 205 case Bytecodes::_if_icmpgt : // fall through 206 case Bytecodes::_if_icmple : // fall through 207 case Bytecodes::_ifeq : // fall through 208 case Bytecodes::_ifne : // fall through 209 case Bytecodes::_iflt : // fall through 210 case Bytecodes::_ifge : // fall through 211 case Bytecodes::_ifgt : // fall through 212 case Bytecodes::_ifle : // fall through 213 case Bytecodes::_ifnonnull : // fall through 214 case Bytecodes::_ifnull : // fall through 215 case Bytecodes::_jsr : { 216 int old_ofs = _s_old->bytecode().get_offset_s2(c_old); 217 int new_ofs = _s_new->bytecode().get_offset_s2(c_new); 218 if (old_ofs != new_ofs) 219 return false; 220 break; 221 } 222 223 case Bytecodes::_iinc : 224 if (_s_old->is_wide() != _s_new->is_wide()) 225 return false; 226 if (! _s_old->is_wide()) { 227 // We could use get_index_u1 and get_constant_u1, but it's simpler to grab both bytes at once: 228 if (Bytes::get_Java_u2(_s_old->bcp() + 1) != Bytes::get_Java_u2(_s_new->bcp() + 1)) 229 return false; 230 } else { 231 // We could use get_index_u2 and get_constant_u2, but it's simpler to grab all four bytes at once: 232 if (Bytes::get_Java_u4(_s_old->bcp() + 1) != Bytes::get_Java_u4(_s_new->bcp() + 1)) 233 return false; 234 } 235 break; 236 237 case Bytecodes::_goto_w : // fall through 238 case Bytecodes::_jsr_w : { 239 int old_ofs = _s_old->bytecode().get_offset_s4(c_old); 240 int new_ofs = _s_new->bytecode().get_offset_s4(c_new); 241 if (old_ofs != new_ofs) 242 return false; 243 break; 244 } 245 246 case Bytecodes::_lookupswitch : // fall through 247 case Bytecodes::_tableswitch : { 248 int len_old = _s_old->instruction_size(); 249 int len_new = _s_new->instruction_size(); 250 if (len_old != len_new) 251 return false; 252 if (memcmp(_s_old->bcp(), _s_new->bcp(), len_old) != 0) 253 return false; 254 break; 255 } 256 } 257 258 return true; 259 } 260 261 bool MethodComparator::pool_constants_same(int cpi_old, int cpi_new) { 262 constantTag tag_old = _old_cp->tag_at(cpi_old); 263 constantTag tag_new = _new_cp->tag_at(cpi_new); 264 if (tag_old.is_int() || tag_old.is_float()) { 265 if (tag_old.value() != tag_new.value()) 266 return false; 267 if (tag_old.is_int()) { 268 if (_old_cp->int_at(cpi_old) != _new_cp->int_at(cpi_new)) 269 return false; 270 } else { 271 // Use jint_cast to compare the bits rather than numerical values. 272 // This makes a difference for NaN constants. 273 if (jint_cast(_old_cp->float_at(cpi_old)) != jint_cast(_new_cp->float_at(cpi_new))) 274 return false; 275 } 276 } else if (tag_old.is_string() && tag_new.is_string()) { 277 if (strcmp(_old_cp->string_at_noresolve(cpi_old), 278 _new_cp->string_at_noresolve(cpi_new)) != 0) 279 return false; 280 if (_old_cp->is_pseudo_string_at(cpi_old) || _new_cp->is_pseudo_string_at(cpi_new)) 281 return (_old_cp->is_pseudo_string_at(cpi_old) == _new_cp->is_pseudo_string_at(cpi_new)); 282 } else if (tag_old.is_klass() || tag_old.is_unresolved_klass()) { 283 // tag_old should be klass - 4881222 284 if (! (tag_new.is_unresolved_klass() || tag_new.is_klass())) 285 return false; 286 if (_old_cp->klass_at_noresolve(cpi_old) != 287 _new_cp->klass_at_noresolve(cpi_new)) 288 return false; 289 } else if (tag_old.is_method_type() && tag_new.is_method_type()) { 290 int mti_old = _old_cp->method_type_index_at(cpi_old); 291 int mti_new = _new_cp->method_type_index_at(cpi_new); 292 if ((_old_cp->symbol_at(mti_old) != _new_cp->symbol_at(mti_new))) 293 return false; 294 } else if (tag_old.is_method_handle() && tag_new.is_method_handle()) { 295 if (_old_cp->method_handle_ref_kind_at(cpi_old) != 296 _new_cp->method_handle_ref_kind_at(cpi_new)) 297 return false; 298 int mhi_old = _old_cp->method_handle_index_at(cpi_old); 299 int mhi_new = _new_cp->method_handle_index_at(cpi_new); 300 if ((_old_cp->uncached_klass_ref_at_noresolve(mhi_old) != _new_cp->uncached_klass_ref_at_noresolve(mhi_new)) || 301 (_old_cp->uncached_name_ref_at(mhi_old) != _new_cp->uncached_name_ref_at(mhi_new)) || 302 (_old_cp->uncached_signature_ref_at(mhi_old) != _new_cp->uncached_signature_ref_at(mhi_new))) 303 return false; 304 } else { 305 return false; // unknown tag 306 } 307 return true; 308 } 309 310 311 int MethodComparator::check_stack_and_locals_size(Method* old_method, Method* new_method) { 312 if (old_method->max_stack() != new_method->max_stack()) { 313 return 1; 314 } else if (old_method->max_locals() != new_method->max_locals()) { 315 return 2; 316 } else if (old_method->size_of_parameters() != new_method->size_of_parameters()) { 317 return 3; 318 } else return 0; 319 }