J. Duke | 8153779 | 2007-12-01 00:00:00 +0000 | [diff] [blame] | 1 | /* |
Jesper Wilhelmsson | efd1054 | 2017-07-06 01:50:26 +0200 | [diff] [blame] | 2 | * Copyright (c) 1997, 2017, Oracle and/or its affiliates. All rights reserved. |
J. Duke | 8153779 | 2007-12-01 00:00:00 +0000 | [diff] [blame] | 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 | * |
Erik Trimble | ba7c173 | 2010-05-27 19:08:38 -0700 | [diff] [blame] | 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. |
J. Duke | 8153779 | 2007-12-01 00:00:00 +0000 | [diff] [blame] | 22 | * |
| 23 | */ |
| 24 | |
Stefan Karlsson | 8006fe8 | 2010-11-23 13:22:55 -0800 | [diff] [blame] | 25 | #include "precompiled.hpp" |
| 26 | #include "classfile/stackMapTableFormat.hpp" |
| 27 | #include "interpreter/bytecodes.hpp" |
Jon Masamitsu | 5c58d27 | 2012-09-01 13:25:18 -0400 | [diff] [blame] | 28 | #include "memory/metadataFactory.hpp" |
Stefan Karlsson | 8006fe8 | 2010-11-23 13:22:55 -0800 | [diff] [blame] | 29 | #include "memory/oopFactory.hpp" |
| 30 | #include "memory/universe.inline.hpp" |
| 31 | #include "oops/oop.inline.hpp" |
| 32 | #include "runtime/handles.inline.hpp" |
| 33 | #include "runtime/relocator.hpp" |
J. Duke | 8153779 | 2007-12-01 00:00:00 +0000 | [diff] [blame] | 34 | |
| 35 | #define MAX_METHOD_LENGTH 65535 |
| 36 | |
| 37 | #define MAX_SHORT ((1 << 15) - 1) |
| 38 | #define MIN_SHORT (- (1 << 15)) |
| 39 | |
| 40 | // Encapsulates a code change request. There are 3 types. |
| 41 | // General instruction, jump instruction, and table/lookup switches |
| 42 | // |
| 43 | class ChangeItem : public ResourceObj { |
| 44 | int _bci; |
| 45 | public: |
| 46 | ChangeItem(int bci) { _bci = bci; } |
| 47 | virtual bool handle_code_change(Relocator *r) = 0; |
| 48 | |
| 49 | // type info |
| 50 | virtual bool is_widen() { return false; } |
| 51 | virtual bool is_jump_widen() { return false; } |
| 52 | virtual bool is_switch_pad() { return false; } |
| 53 | |
| 54 | // accessors |
| 55 | int bci() { return _bci; } |
| 56 | void relocate(int break_bci, int delta) { if (_bci > break_bci) { _bci += delta; } } |
| 57 | |
| 58 | virtual bool adjust(int bci, int delta) { return false; } |
| 59 | |
| 60 | // debug |
| 61 | virtual void print() = 0; |
| 62 | }; |
| 63 | |
| 64 | class ChangeWiden : public ChangeItem { |
| 65 | int _new_ilen; // New length of instruction at bci |
| 66 | u_char* _inst_buffer; // New bytecodes |
| 67 | public: |
| 68 | ChangeWiden(int bci, int new_ilen, u_char* inst_buffer) : ChangeItem(bci) { |
| 69 | _new_ilen = new_ilen; |
| 70 | _inst_buffer = inst_buffer; |
| 71 | } |
| 72 | |
| 73 | // Callback to do instruction |
| 74 | bool handle_code_change(Relocator *r) { return r->handle_widen(bci(), _new_ilen, _inst_buffer); }; |
| 75 | |
| 76 | bool is_widen() { return true; } |
| 77 | |
| 78 | void print() { tty->print_cr("ChangeWiden. bci: %d New_ilen: %d", bci(), _new_ilen); } |
| 79 | }; |
| 80 | |
| 81 | class ChangeJumpWiden : public ChangeItem { |
| 82 | int _delta; // New length of instruction at bci |
| 83 | public: |
| 84 | ChangeJumpWiden(int bci, int delta) : ChangeItem(bci) { _delta = delta; } |
| 85 | |
| 86 | // Callback to do instruction |
| 87 | bool handle_code_change(Relocator *r) { return r->handle_jump_widen(bci(), _delta); }; |
| 88 | |
| 89 | bool is_jump_widen() { return true; } |
| 90 | |
| 91 | // If the bci matches, adjust the delta in the change jump request. |
| 92 | bool adjust(int jump_bci, int delta) { |
| 93 | if (bci() == jump_bci) { |
| 94 | if (_delta > 0) |
| 95 | _delta += delta; |
| 96 | else |
| 97 | _delta -= delta; |
| 98 | return true; |
| 99 | } |
| 100 | return false; |
| 101 | } |
| 102 | |
| 103 | void print() { tty->print_cr("ChangeJumpWiden. bci: %d Delta: %d", bci(), _delta); } |
| 104 | }; |
| 105 | |
| 106 | class ChangeSwitchPad : public ChangeItem { |
| 107 | int _padding; |
| 108 | bool _is_lookup_switch; |
| 109 | public: |
| 110 | ChangeSwitchPad(int bci, int padding, bool is_lookup_switch) : ChangeItem(bci) { |
| 111 | _padding = padding; |
| 112 | _is_lookup_switch = is_lookup_switch; |
| 113 | } |
| 114 | |
| 115 | // Callback to do instruction |
| 116 | bool handle_code_change(Relocator *r) { return r->handle_switch_pad(bci(), _padding, _is_lookup_switch); }; |
| 117 | |
| 118 | bool is_switch_pad() { return true; } |
| 119 | int padding() { return _padding; } |
| 120 | bool is_lookup_switch() { return _is_lookup_switch; } |
| 121 | |
| 122 | void print() { tty->print_cr("ChangeSwitchPad. bci: %d Padding: %d IsLookupSwitch: %d", bci(), _padding, _is_lookup_switch); } |
| 123 | }; |
| 124 | |
| 125 | //----------------------------------------------------------------------------------------------------------- |
| 126 | // Relocator code |
| 127 | |
Coleen Phillimore | f1e89ea | 2015-10-23 16:48:38 -0400 | [diff] [blame] | 128 | Relocator::Relocator(const methodHandle& m, RelocatorListener* listener) { |
J. Duke | 8153779 | 2007-12-01 00:00:00 +0000 | [diff] [blame] | 129 | set_method(m); |
| 130 | set_code_length(method()->code_size()); |
| 131 | set_code_array(NULL); |
| 132 | // Allocate code array and copy bytecodes |
| 133 | if (!expand_code_array(0)) { |
| 134 | // Should have at least MAX_METHOD_LENGTH available or the verifier |
| 135 | // would have failed. |
| 136 | ShouldNotReachHere(); |
| 137 | } |
| 138 | set_compressed_line_number_table(NULL); |
| 139 | set_compressed_line_number_table_size(0); |
| 140 | _listener = listener; |
| 141 | } |
| 142 | |
| 143 | // size is the new size of the instruction at bci. Hence, if size is less than the current |
Jesper Wilhelmsson | 81ba2e3 | 2014-01-23 14:47:23 +0100 | [diff] [blame] | 144 | // instruction size, we will shrink the code. |
J. Duke | 8153779 | 2007-12-01 00:00:00 +0000 | [diff] [blame] | 145 | methodHandle Relocator::insert_space_at(int bci, int size, u_char inst_buffer[], TRAPS) { |
| 146 | _changes = new GrowableArray<ChangeItem*> (10); |
| 147 | _changes->push(new ChangeWiden(bci, size, inst_buffer)); |
| 148 | |
| 149 | if (TraceRelocator) { |
| 150 | tty->print_cr("Space at: %d Size: %d", bci, size); |
| 151 | _method->print(); |
| 152 | _method->print_codes(); |
| 153 | tty->print_cr("-------------------------------------------------"); |
| 154 | } |
| 155 | |
| 156 | if (!handle_code_changes()) return methodHandle(); |
| 157 | |
| 158 | // Construct the new method |
Jon Masamitsu | 5c58d27 | 2012-09-01 13:25:18 -0400 | [diff] [blame] | 159 | methodHandle new_method = Method::clone_with_new_data(method(), |
J. Duke | 8153779 | 2007-12-01 00:00:00 +0000 | [diff] [blame] | 160 | code_array(), code_length(), |
| 161 | compressed_line_number_table(), |
| 162 | compressed_line_number_table_size(), |
| 163 | CHECK_(methodHandle())); |
Jon Masamitsu | 5c58d27 | 2012-09-01 13:25:18 -0400 | [diff] [blame] | 164 | |
| 165 | // Deallocate the old Method* from metadata |
| 166 | ClassLoaderData* loader_data = method()->method_holder()->class_loader_data(); |
| 167 | loader_data->add_to_deallocate_list(method()()); |
| 168 | |
J. Duke | 8153779 | 2007-12-01 00:00:00 +0000 | [diff] [blame] | 169 | set_method(new_method); |
| 170 | |
| 171 | if (TraceRelocator) { |
| 172 | tty->print_cr("-------------------------------------------------"); |
| 173 | tty->print_cr("new method"); |
| 174 | _method->print_codes(); |
| 175 | } |
| 176 | |
| 177 | return new_method; |
| 178 | } |
| 179 | |
| 180 | |
| 181 | bool Relocator::handle_code_changes() { |
| 182 | assert(_changes != NULL, "changes vector must be initialized"); |
| 183 | |
| 184 | while (!_changes->is_empty()) { |
| 185 | // Inv: everything is aligned. |
| 186 | ChangeItem* ci = _changes->first(); |
| 187 | |
| 188 | if (TraceRelocator) { |
| 189 | ci->print(); |
| 190 | } |
| 191 | |
| 192 | // Execute operation |
| 193 | if (!ci->handle_code_change(this)) return false; |
| 194 | |
Jesper Wilhelmsson | 81ba2e3 | 2014-01-23 14:47:23 +0100 | [diff] [blame] | 195 | // Shuffle items up |
J. Duke | 8153779 | 2007-12-01 00:00:00 +0000 | [diff] [blame] | 196 | for (int index = 1; index < _changes->length(); index++) { |
| 197 | _changes->at_put(index-1, _changes->at(index)); |
| 198 | } |
| 199 | _changes->pop(); |
| 200 | } |
| 201 | return true; |
| 202 | } |
| 203 | |
| 204 | |
| 205 | bool Relocator::is_opcode_lookupswitch(Bytecodes::Code bc) { |
| 206 | switch (bc) { |
| 207 | case Bytecodes::_tableswitch: return false; |
| 208 | case Bytecodes::_lookupswitch: // not rewritten on ia64 |
| 209 | case Bytecodes::_fast_linearswitch: // rewritten _lookupswitch |
| 210 | case Bytecodes::_fast_binaryswitch: return true; // rewritten _lookupswitch |
| 211 | default: ShouldNotReachHere(); |
| 212 | } |
| 213 | return true; // dummy |
| 214 | } |
| 215 | |
| 216 | // We need a special instruction size method, since lookupswitches and tableswitches might not be |
Jesper Wilhelmsson | 81ba2e3 | 2014-01-23 14:47:23 +0100 | [diff] [blame] | 217 | // properly aligned during relocation |
J. Duke | 8153779 | 2007-12-01 00:00:00 +0000 | [diff] [blame] | 218 | int Relocator::rc_instr_len(int bci) { |
| 219 | Bytecodes::Code bc= code_at(bci); |
| 220 | switch (bc) { |
| 221 | // In the case of switch instructions, see if we have the original |
| 222 | // padding recorded. |
| 223 | case Bytecodes::_tableswitch: |
| 224 | case Bytecodes::_lookupswitch: |
| 225 | case Bytecodes::_fast_linearswitch: |
| 226 | case Bytecodes::_fast_binaryswitch: |
| 227 | { |
| 228 | int pad = get_orig_switch_pad(bci, is_opcode_lookupswitch(bc)); |
| 229 | if (pad == -1) { |
| 230 | return instruction_length_at(bci); |
| 231 | } |
| 232 | // Otherwise, depends on the switch type. |
| 233 | switch (bc) { |
| 234 | case Bytecodes::_tableswitch: { |
| 235 | int lo = int_at(bci + 1 + pad + 4 * 1); |
| 236 | int hi = int_at(bci + 1 + pad + 4 * 2); |
| 237 | int n = hi - lo + 1; |
| 238 | return 1 + pad + 4*(3 + n); |
| 239 | } |
| 240 | case Bytecodes::_lookupswitch: |
| 241 | case Bytecodes::_fast_linearswitch: |
| 242 | case Bytecodes::_fast_binaryswitch: { |
| 243 | int npairs = int_at(bci + 1 + pad + 4 * 1); |
| 244 | return 1 + pad + 4*(2 + 2*npairs); |
| 245 | } |
| 246 | default: |
| 247 | ShouldNotReachHere(); |
| 248 | } |
| 249 | } |
Jesper Wilhelmsson | efd1054 | 2017-07-06 01:50:26 +0200 | [diff] [blame] | 250 | default: |
| 251 | break; |
J. Duke | 8153779 | 2007-12-01 00:00:00 +0000 | [diff] [blame] | 252 | } |
| 253 | return instruction_length_at(bci); |
| 254 | } |
| 255 | |
| 256 | // If a change item is recorded for "pc", with type "ct", returns the |
| 257 | // associated padding, else -1. |
| 258 | int Relocator::get_orig_switch_pad(int bci, bool is_lookup_switch) { |
| 259 | for (int k = 0; k < _changes->length(); k++) { |
| 260 | ChangeItem* ci = _changes->at(k); |
| 261 | if (ci->is_switch_pad()) { |
| 262 | ChangeSwitchPad* csp = (ChangeSwitchPad*)ci; |
| 263 | if (csp->is_lookup_switch() == is_lookup_switch && csp->bci() == bci) { |
| 264 | return csp->padding(); |
| 265 | } |
| 266 | } |
| 267 | } |
| 268 | return -1; |
| 269 | } |
| 270 | |
| 271 | |
| 272 | // Push a ChangeJumpWiden if it doesn't already exist on the work queue, |
| 273 | // otherwise adjust the item already there by delta. The calculation for |
| 274 | // new_delta is wrong for this because it uses the offset stored in the |
| 275 | // code stream itself which wasn't fixed when item was pushed on the work queue. |
| 276 | void Relocator::push_jump_widen(int bci, int delta, int new_delta) { |
| 277 | for (int j = 0; j < _changes->length(); j++) { |
| 278 | ChangeItem* ci = _changes->at(j); |
| 279 | if (ci->adjust(bci, delta)) return; |
| 280 | } |
| 281 | _changes->push(new ChangeJumpWiden(bci, new_delta)); |
| 282 | } |
| 283 | |
| 284 | |
| 285 | // The current instruction of "c" is a jump; one of its offset starts |
| 286 | // at "offset" and is a short if "isShort" is "TRUE", |
| 287 | // and an integer otherwise. If the jump crosses "breakPC", change |
| 288 | // the span of the jump by "delta". |
| 289 | void Relocator::change_jump(int bci, int offset, bool is_short, int break_bci, int delta) { |
| 290 | int bci_delta = (is_short) ? short_at(offset) : int_at(offset); |
| 291 | int targ = bci + bci_delta; |
| 292 | |
| 293 | if ((bci <= break_bci && targ > break_bci) || |
| 294 | (bci > break_bci && targ <= break_bci)) { |
| 295 | int new_delta; |
| 296 | if (bci_delta > 0) |
| 297 | new_delta = bci_delta + delta; |
| 298 | else |
| 299 | new_delta = bci_delta - delta; |
| 300 | |
| 301 | if (is_short && ((new_delta > MAX_SHORT) || new_delta < MIN_SHORT)) { |
| 302 | push_jump_widen(bci, delta, new_delta); |
| 303 | } else if (is_short) { |
| 304 | short_at_put(offset, new_delta); |
| 305 | } else { |
| 306 | int_at_put(offset, new_delta); |
| 307 | } |
| 308 | } |
| 309 | } |
| 310 | |
| 311 | |
| 312 | // Changes all jumps crossing "break_bci" by "delta". May enqueue things |
| 313 | // on "rc->changes" |
| 314 | void Relocator::change_jumps(int break_bci, int delta) { |
| 315 | int bci = 0; |
| 316 | Bytecodes::Code bc; |
| 317 | // Now, adjust any affected instructions. |
| 318 | while (bci < code_length()) { |
| 319 | switch (bc= code_at(bci)) { |
| 320 | case Bytecodes::_ifeq: |
| 321 | case Bytecodes::_ifne: |
| 322 | case Bytecodes::_iflt: |
| 323 | case Bytecodes::_ifge: |
| 324 | case Bytecodes::_ifgt: |
| 325 | case Bytecodes::_ifle: |
| 326 | case Bytecodes::_if_icmpeq: |
| 327 | case Bytecodes::_if_icmpne: |
| 328 | case Bytecodes::_if_icmplt: |
| 329 | case Bytecodes::_if_icmpge: |
| 330 | case Bytecodes::_if_icmpgt: |
| 331 | case Bytecodes::_if_icmple: |
| 332 | case Bytecodes::_if_acmpeq: |
| 333 | case Bytecodes::_if_acmpne: |
| 334 | case Bytecodes::_ifnull: |
| 335 | case Bytecodes::_ifnonnull: |
| 336 | case Bytecodes::_goto: |
| 337 | case Bytecodes::_jsr: |
| 338 | change_jump(bci, bci+1, true, break_bci, delta); |
| 339 | break; |
| 340 | case Bytecodes::_goto_w: |
| 341 | case Bytecodes::_jsr_w: |
| 342 | change_jump(bci, bci+1, false, break_bci, delta); |
| 343 | break; |
| 344 | case Bytecodes::_tableswitch: |
| 345 | case Bytecodes::_lookupswitch: |
| 346 | case Bytecodes::_fast_linearswitch: |
| 347 | case Bytecodes::_fast_binaryswitch: { |
| 348 | int recPad = get_orig_switch_pad(bci, (bc != Bytecodes::_tableswitch)); |
| 349 | int oldPad = (recPad != -1) ? recPad : align(bci+1) - (bci+1); |
| 350 | if (bci > break_bci) { |
| 351 | int new_bci = bci + delta; |
| 352 | int newPad = align(new_bci+1) - (new_bci+1); |
| 353 | // Do we need to check the padding? |
| 354 | if (newPad != oldPad) { |
| 355 | if (recPad == -1) { |
| 356 | _changes->push(new ChangeSwitchPad(bci, oldPad, (bc != Bytecodes::_tableswitch))); |
| 357 | } |
| 358 | } |
| 359 | } |
| 360 | |
| 361 | // Then the rest, which depend on the kind of switch. |
| 362 | switch (bc) { |
| 363 | case Bytecodes::_tableswitch: { |
| 364 | change_jump(bci, bci +1 + oldPad, false, break_bci, delta); |
| 365 | // We cannot use the Bytecode_tableswitch abstraction, since the padding might not be correct. |
| 366 | int lo = int_at(bci + 1 + oldPad + 4 * 1); |
| 367 | int hi = int_at(bci + 1 + oldPad + 4 * 2); |
| 368 | int n = hi - lo + 1; |
| 369 | for (int k = 0; k < n; k++) { |
| 370 | change_jump(bci, bci +1 + oldPad + 4*(k+3), false, break_bci, delta); |
| 371 | } |
| 372 | // Special next-bci calculation here... |
| 373 | bci += 1 + oldPad + (n+3)*4; |
| 374 | continue; |
| 375 | } |
| 376 | case Bytecodes::_lookupswitch: |
| 377 | case Bytecodes::_fast_linearswitch: |
| 378 | case Bytecodes::_fast_binaryswitch: { |
| 379 | change_jump(bci, bci +1 + oldPad, false, break_bci, delta); |
| 380 | // We cannot use the Bytecode_lookupswitch abstraction, since the padding might not be correct. |
| 381 | int npairs = int_at(bci + 1 + oldPad + 4 * 1); |
| 382 | for (int k = 0; k < npairs; k++) { |
| 383 | change_jump(bci, bci + 1 + oldPad + 4*(2 + 2*k + 1), false, break_bci, delta); |
| 384 | } |
| 385 | /* Special next-bci calculation here... */ |
| 386 | bci += 1 + oldPad + (2 + (npairs*2))*4; |
| 387 | continue; |
| 388 | } |
| 389 | default: |
| 390 | ShouldNotReachHere(); |
| 391 | } |
| 392 | } |
| 393 | default: |
| 394 | break; |
| 395 | } |
| 396 | bci += rc_instr_len(bci); |
| 397 | } |
| 398 | } |
| 399 | |
| 400 | // The width of instruction at "pc" is changing by "delta". Adjust the |
| 401 | // exception table, if any, of "rc->mb". |
| 402 | void Relocator::adjust_exception_table(int bci, int delta) { |
Jiangli Zhou | 56df3bd | 2012-06-26 19:08:44 -0400 | [diff] [blame] | 403 | ExceptionTable table(_method()); |
| 404 | for (int index = 0; index < table.length(); index ++) { |
| 405 | if (table.start_pc(index) > bci) { |
| 406 | table.set_start_pc(index, table.start_pc(index) + delta); |
| 407 | table.set_end_pc(index, table.end_pc(index) + delta); |
| 408 | } else if (bci < table.end_pc(index)) { |
| 409 | table.set_end_pc(index, table.end_pc(index) + delta); |
J. Duke | 8153779 | 2007-12-01 00:00:00 +0000 | [diff] [blame] | 410 | } |
Jiangli Zhou | 56df3bd | 2012-06-26 19:08:44 -0400 | [diff] [blame] | 411 | if (table.handler_pc(index) > bci) |
| 412 | table.set_handler_pc(index, table.handler_pc(index) + delta); |
J. Duke | 8153779 | 2007-12-01 00:00:00 +0000 | [diff] [blame] | 413 | } |
| 414 | } |
| 415 | |
| 416 | |
| 417 | // The width of instruction at "bci" is changing by "delta". Adjust the line number table. |
| 418 | void Relocator::adjust_line_no_table(int bci, int delta) { |
| 419 | if (method()->has_linenumber_table()) { |
| 420 | CompressedLineNumberReadStream reader(method()->compressed_linenumber_table()); |
| 421 | CompressedLineNumberWriteStream writer(64); // plenty big for most line number tables |
| 422 | while (reader.read_pair()) { |
| 423 | int adjustment = (reader.bci() > bci) ? delta : 0; |
| 424 | writer.write_pair(reader.bci() + adjustment, reader.line()); |
| 425 | } |
| 426 | writer.write_terminator(); |
| 427 | set_compressed_line_number_table(writer.buffer()); |
| 428 | set_compressed_line_number_table_size(writer.position()); |
| 429 | } |
| 430 | } |
| 431 | |
| 432 | |
| 433 | // The width of instruction at "bci" is changing by "delta". Adjust the local variable table. |
| 434 | void Relocator::adjust_local_var_table(int bci, int delta) { |
| 435 | int localvariable_table_length = method()->localvariable_table_length(); |
| 436 | if (localvariable_table_length > 0) { |
| 437 | LocalVariableTableElement* table = method()->localvariable_table_start(); |
| 438 | for (int i = 0; i < localvariable_table_length; i++) { |
| 439 | u2 current_bci = table[i].start_bci; |
| 440 | if (current_bci > bci) { |
| 441 | table[i].start_bci = current_bci + delta; |
| 442 | } else { |
| 443 | u2 current_length = table[i].length; |
| 444 | if (current_bci + current_length > bci) { |
| 445 | table[i].length = current_length + delta; |
| 446 | } |
| 447 | } |
| 448 | } |
| 449 | } |
| 450 | } |
| 451 | |
Keith McGuigan | c340115 | 2010-10-21 10:10:23 -0400 | [diff] [blame] | 452 | // Create a new array, copying the src array but adding a hole at |
| 453 | // the specified location |
Jon Masamitsu | 5c58d27 | 2012-09-01 13:25:18 -0400 | [diff] [blame] | 454 | static Array<u1>* insert_hole_at(ClassLoaderData* loader_data, |
| 455 | size_t where, int hole_sz, Array<u1>* src) { |
Keith McGuigan | c340115 | 2010-10-21 10:10:23 -0400 | [diff] [blame] | 456 | Thread* THREAD = Thread::current(); |
Jon Masamitsu | 5c58d27 | 2012-09-01 13:25:18 -0400 | [diff] [blame] | 457 | Array<u1>* dst = |
| 458 | MetadataFactory::new_array<u1>(loader_data, src->length() + hole_sz, 0, CHECK_NULL); |
Keith McGuigan | c340115 | 2010-10-21 10:10:23 -0400 | [diff] [blame] | 459 | |
Jon Masamitsu | 5c58d27 | 2012-09-01 13:25:18 -0400 | [diff] [blame] | 460 | address src_addr = (address)src->adr_at(0); |
| 461 | address dst_addr = (address)dst->adr_at(0); |
Keith McGuigan | c340115 | 2010-10-21 10:10:23 -0400 | [diff] [blame] | 462 | |
| 463 | memcpy(dst_addr, src_addr, where); |
| 464 | memcpy(dst_addr + where + hole_sz, |
| 465 | src_addr + where, src->length() - where); |
| 466 | return dst; |
| 467 | } |
| 468 | |
| 469 | // The width of instruction at "bci" is changing by "delta". Adjust the stack |
| 470 | // map frames. |
| 471 | void Relocator::adjust_stack_map_table(int bci, int delta) { |
| 472 | if (method()->has_stackmap_table()) { |
Jon Masamitsu | 5c58d27 | 2012-09-01 13:25:18 -0400 | [diff] [blame] | 473 | Array<u1>* data = method()->stackmap_data(); |
Keith McGuigan | dbe25e4 | 2012-08-06 15:54:45 -0400 | [diff] [blame] | 474 | // The data in the array is a classfile representation of the stackmap table |
| 475 | stack_map_table* sm_table = |
Jon Masamitsu | 5c58d27 | 2012-09-01 13:25:18 -0400 | [diff] [blame] | 476 | stack_map_table::at((address)data->adr_at(0)); |
Keith McGuigan | c340115 | 2010-10-21 10:10:23 -0400 | [diff] [blame] | 477 | |
Keith McGuigan | dbe25e4 | 2012-08-06 15:54:45 -0400 | [diff] [blame] | 478 | int count = sm_table->number_of_entries(); |
| 479 | stack_map_frame* frame = sm_table->entries(); |
Keith McGuigan | c340115 | 2010-10-21 10:10:23 -0400 | [diff] [blame] | 480 | int bci_iter = -1; |
| 481 | bool offset_adjusted = false; // only need to adjust one offset |
| 482 | |
| 483 | for (int i = 0; i < count; ++i) { |
| 484 | int offset_delta = frame->offset_delta(); |
| 485 | bci_iter += offset_delta; |
| 486 | |
| 487 | if (!offset_adjusted && bci_iter > bci) { |
| 488 | int new_offset_delta = offset_delta + delta; |
| 489 | |
| 490 | if (frame->is_valid_offset(new_offset_delta)) { |
| 491 | frame->set_offset_delta(new_offset_delta); |
| 492 | } else { |
| 493 | assert(frame->is_same_frame() || |
Keith McGuigan | dbe25e4 | 2012-08-06 15:54:45 -0400 | [diff] [blame] | 494 | frame->is_same_locals_1_stack_item_frame(), |
Keith McGuigan | c340115 | 2010-10-21 10:10:23 -0400 | [diff] [blame] | 495 | "Frame must be one of the compressed forms"); |
| 496 | // The new delta exceeds the capacity of the 'same_frame' or |
| 497 | // 'same_frame_1_stack_item_frame' frame types. We need to |
| 498 | // convert these frames to the extended versions, but the extended |
| 499 | // version is bigger and requires more room. So we allocate a |
| 500 | // new array and copy the data, being sure to leave u2-sized hole |
| 501 | // right after the 'frame_type' for the new offset field. |
| 502 | // |
| 503 | // We can safely ignore the reverse situation as a small delta |
| 504 | // can still be used in an extended version of the frame. |
| 505 | |
Jon Masamitsu | 5c58d27 | 2012-09-01 13:25:18 -0400 | [diff] [blame] | 506 | size_t frame_offset = (address)frame - (address)data->adr_at(0); |
Keith McGuigan | c340115 | 2010-10-21 10:10:23 -0400 | [diff] [blame] | 507 | |
Jon Masamitsu | 5c58d27 | 2012-09-01 13:25:18 -0400 | [diff] [blame] | 508 | ClassLoaderData* loader_data = method()->method_holder()->class_loader_data(); |
| 509 | Array<u1>* new_data = insert_hole_at(loader_data, frame_offset + 1, 2, data); |
| 510 | if (new_data == NULL) { |
Keith McGuigan | c340115 | 2010-10-21 10:10:23 -0400 | [diff] [blame] | 511 | return; // out-of-memory? |
| 512 | } |
Jon Masamitsu | 5c58d27 | 2012-09-01 13:25:18 -0400 | [diff] [blame] | 513 | // Deallocate old data |
| 514 | MetadataFactory::free_array<u1>(loader_data, data); |
| 515 | data = new_data; |
Keith McGuigan | c340115 | 2010-10-21 10:10:23 -0400 | [diff] [blame] | 516 | |
Jon Masamitsu | 5c58d27 | 2012-09-01 13:25:18 -0400 | [diff] [blame] | 517 | address frame_addr = (address)(data->adr_at(0) + frame_offset); |
Keith McGuigan | c340115 | 2010-10-21 10:10:23 -0400 | [diff] [blame] | 518 | frame = stack_map_frame::at(frame_addr); |
| 519 | |
| 520 | |
| 521 | // Now convert the frames in place |
| 522 | if (frame->is_same_frame()) { |
| 523 | same_frame_extended::create_at(frame_addr, new_offset_delta); |
| 524 | } else { |
Keith McGuigan | dbe25e4 | 2012-08-06 15:54:45 -0400 | [diff] [blame] | 525 | same_locals_1_stack_item_extended::create_at( |
Keith McGuigan | c340115 | 2010-10-21 10:10:23 -0400 | [diff] [blame] | 526 | frame_addr, new_offset_delta, NULL); |
| 527 | // the verification_info_type should already be at the right spot |
| 528 | } |
| 529 | } |
| 530 | offset_adjusted = true; // needs to be done only once, since subsequent |
| 531 | // values are offsets from the current |
| 532 | } |
| 533 | |
| 534 | // The stack map frame may contain verification types, if so we need to |
| 535 | // check and update any Uninitialized type's bci (no matter where it is). |
| 536 | int number_of_types = frame->number_of_types(); |
| 537 | verification_type_info* types = frame->types(); |
| 538 | |
| 539 | for (int i = 0; i < number_of_types; ++i) { |
| 540 | if (types->is_uninitialized() && types->bci() > bci) { |
| 541 | types->set_bci(types->bci() + delta); |
| 542 | } |
| 543 | types = types->next(); |
| 544 | } |
| 545 | |
| 546 | // Full frame has stack values too |
| 547 | full_frame* ff = frame->as_full_frame(); |
| 548 | if (ff != NULL) { |
| 549 | address eol = (address)types; |
| 550 | number_of_types = ff->stack_slots(eol); |
| 551 | types = ff->stack(eol); |
| 552 | for (int i = 0; i < number_of_types; ++i) { |
| 553 | if (types->is_uninitialized() && types->bci() > bci) { |
| 554 | types->set_bci(types->bci() + delta); |
| 555 | } |
| 556 | types = types->next(); |
| 557 | } |
| 558 | } |
| 559 | |
| 560 | frame = frame->next(); |
| 561 | } |
| 562 | |
| 563 | method()->set_stackmap_data(data); // in case it has changed |
| 564 | } |
| 565 | } |
| 566 | |
J. Duke | 8153779 | 2007-12-01 00:00:00 +0000 | [diff] [blame] | 567 | |
| 568 | bool Relocator::expand_code_array(int delta) { |
| 569 | int length = MAX2(code_length() + delta, code_length() * (100+code_slop_pct()) / 100); |
| 570 | |
| 571 | if (length > MAX_METHOD_LENGTH) { |
| 572 | if (delta == 0 && code_length() <= MAX_METHOD_LENGTH) { |
| 573 | length = MAX_METHOD_LENGTH; |
| 574 | } else { |
| 575 | return false; |
| 576 | } |
| 577 | } |
| 578 | |
| 579 | unsigned char* new_code_array = NEW_RESOURCE_ARRAY(unsigned char, length); |
| 580 | if (!new_code_array) return false; |
| 581 | |
| 582 | // Expanding current array |
| 583 | if (code_array() != NULL) { |
| 584 | memcpy(new_code_array, code_array(), code_length()); |
| 585 | } else { |
Jon Masamitsu | 5c58d27 | 2012-09-01 13:25:18 -0400 | [diff] [blame] | 586 | // Initial copy. Copy directly from Method* |
J. Duke | 8153779 | 2007-12-01 00:00:00 +0000 | [diff] [blame] | 587 | memcpy(new_code_array, method()->code_base(), code_length()); |
| 588 | } |
| 589 | |
| 590 | set_code_array(new_code_array); |
| 591 | set_code_array_length(length); |
| 592 | |
| 593 | return true; |
| 594 | } |
| 595 | |
| 596 | |
| 597 | // The instruction at "bci", whose size is "ilen", is changing size by |
| 598 | // "delta". Reallocate, move code, recalculate jumps, and enqueue |
| 599 | // change items as necessary. |
| 600 | bool Relocator::relocate_code(int bci, int ilen, int delta) { |
| 601 | int next_bci = bci + ilen; |
| 602 | if (delta > 0 && code_length() + delta > code_array_length()) { |
| 603 | // Expand allocated code space, if necessary. |
| 604 | if (!expand_code_array(delta)) { |
| 605 | return false; |
| 606 | } |
| 607 | } |
| 608 | |
| 609 | // We require 4-byte alignment of code arrays. |
| 610 | assert(((intptr_t)code_array() & 3) == 0, "check code alignment"); |
| 611 | // Change jumps before doing the copying; this routine requires aligned switches. |
| 612 | change_jumps(bci, delta); |
| 613 | |
| 614 | // In case we have shrunken a tableswitch/lookupswitch statement, we store the last |
| 615 | // bytes that get overwritten. We have to copy the bytes after the change_jumps method |
Jesper Wilhelmsson | 81ba2e3 | 2014-01-23 14:47:23 +0100 | [diff] [blame] | 616 | // has been called, since it is likely to update last offset in a tableswitch/lookupswitch |
Goetz Lindenmaier | 1e4b00b | 2016-05-03 12:23:06 +0200 | [diff] [blame] | 617 | assert(delta >= -3, "We cannot overwrite more than 3 bytes."); |
| 618 | if (delta < 0 && delta >= -3) { |
J. Duke | 8153779 | 2007-12-01 00:00:00 +0000 | [diff] [blame] | 619 | memcpy(_overwrite, addr_at(bci + ilen + delta), -delta); |
| 620 | } |
| 621 | |
| 622 | memmove(addr_at(next_bci + delta), addr_at(next_bci), code_length() - next_bci); |
| 623 | set_code_length(code_length() + delta); |
| 624 | // Also adjust exception tables... |
| 625 | adjust_exception_table(bci, delta); |
| 626 | // Line number tables... |
| 627 | adjust_line_no_table(bci, delta); |
| 628 | // And local variable table... |
| 629 | adjust_local_var_table(bci, delta); |
| 630 | |
Keith McGuigan | c340115 | 2010-10-21 10:10:23 -0400 | [diff] [blame] | 631 | // Adjust stack maps |
| 632 | adjust_stack_map_table(bci, delta); |
| 633 | |
J. Duke | 8153779 | 2007-12-01 00:00:00 +0000 | [diff] [blame] | 634 | // Relocate the pending change stack... |
| 635 | for (int j = 0; j < _changes->length(); j++) { |
| 636 | ChangeItem* ci = _changes->at(j); |
| 637 | ci->relocate(bci, delta); |
| 638 | } |
| 639 | |
| 640 | // Notify any listeners about code relocation |
| 641 | notify(bci, delta, code_length()); |
| 642 | |
| 643 | return true; |
| 644 | } |
| 645 | |
| 646 | // relocate a general instruction. Called by ChangeWiden class |
| 647 | bool Relocator::handle_widen(int bci, int new_ilen, u_char inst_buffer[]) { |
| 648 | int ilen = rc_instr_len(bci); |
| 649 | if (!relocate_code(bci, ilen, new_ilen - ilen)) |
| 650 | return false; |
| 651 | |
| 652 | // Insert new bytecode(s) |
| 653 | for(int k = 0; k < new_ilen; k++) { |
| 654 | code_at_put(bci + k, (Bytecodes::Code)inst_buffer[k]); |
| 655 | } |
| 656 | |
| 657 | return true; |
| 658 | } |
| 659 | |
| 660 | // handle jump_widen instruction. Called be ChangeJumpWiden class |
| 661 | bool Relocator::handle_jump_widen(int bci, int delta) { |
| 662 | int ilen = rc_instr_len(bci); |
| 663 | |
| 664 | Bytecodes::Code bc = code_at(bci); |
| 665 | switch (bc) { |
| 666 | case Bytecodes::_ifeq: |
| 667 | case Bytecodes::_ifne: |
| 668 | case Bytecodes::_iflt: |
| 669 | case Bytecodes::_ifge: |
| 670 | case Bytecodes::_ifgt: |
| 671 | case Bytecodes::_ifle: |
| 672 | case Bytecodes::_if_icmpeq: |
| 673 | case Bytecodes::_if_icmpne: |
| 674 | case Bytecodes::_if_icmplt: |
| 675 | case Bytecodes::_if_icmpge: |
| 676 | case Bytecodes::_if_icmpgt: |
| 677 | case Bytecodes::_if_icmple: |
| 678 | case Bytecodes::_if_acmpeq: |
| 679 | case Bytecodes::_if_acmpne: |
| 680 | case Bytecodes::_ifnull: |
| 681 | case Bytecodes::_ifnonnull: { |
| 682 | const int goto_length = Bytecodes::length_for(Bytecodes::_goto); |
| 683 | |
| 684 | // If 'if' points to the next bytecode after goto, it's already handled. |
| 685 | // it shouldn't be. |
| 686 | assert (short_at(bci+1) != ilen+goto_length, "if relocation already handled"); |
| 687 | assert(ilen == 3, "check length"); |
| 688 | |
| 689 | // Convert to 0 if <cond> goto 6 |
| 690 | // 3 _goto 11 |
| 691 | // 6 _goto_w <wide delta offset> |
| 692 | // 11 <else code> |
| 693 | const int goto_w_length = Bytecodes::length_for(Bytecodes::_goto_w); |
| 694 | const int add_bci = goto_length + goto_w_length; |
| 695 | |
| 696 | if (!relocate_code(bci, 3, /*delta*/add_bci)) return false; |
| 697 | |
| 698 | // if bytecode points to goto_w instruction |
| 699 | short_at_put(bci + 1, ilen + goto_length); |
| 700 | |
| 701 | int cbci = bci + ilen; |
| 702 | // goto around |
| 703 | code_at_put(cbci, Bytecodes::_goto); |
| 704 | short_at_put(cbci + 1, add_bci); |
| 705 | // goto_w <wide delta> |
| 706 | cbci = cbci + goto_length; |
| 707 | code_at_put(cbci, Bytecodes::_goto_w); |
| 708 | if (delta > 0) { |
| 709 | delta += 2; // goto_w is 2 bytes more than "if" code |
| 710 | } else { |
| 711 | delta -= ilen+goto_length; // branch starts at goto_w offset |
| 712 | } |
| 713 | int_at_put(cbci + 1, delta); |
| 714 | break; |
| 715 | |
| 716 | } |
| 717 | case Bytecodes::_goto: |
| 718 | case Bytecodes::_jsr: |
| 719 | assert(ilen == 3, "check length"); |
| 720 | |
| 721 | if (!relocate_code(bci, 3, 2)) return false; |
| 722 | if (bc == Bytecodes::_goto) |
| 723 | code_at_put(bci, Bytecodes::_goto_w); |
| 724 | else |
| 725 | code_at_put(bci, Bytecodes::_jsr_w); |
| 726 | |
| 727 | // If it's a forward jump, add 2 for the widening. |
| 728 | if (delta > 0) delta += 2; |
| 729 | int_at_put(bci + 1, delta); |
| 730 | break; |
| 731 | |
| 732 | default: ShouldNotReachHere(); |
| 733 | } |
| 734 | |
| 735 | return true; |
| 736 | } |
| 737 | |
| 738 | // handle lookup/table switch instructions. Called be ChangeSwitchPad class |
| 739 | bool Relocator::handle_switch_pad(int bci, int old_pad, bool is_lookup_switch) { |
| 740 | int ilen = rc_instr_len(bci); |
| 741 | int new_pad = align(bci+1) - (bci+1); |
| 742 | int pad_delta = new_pad - old_pad; |
| 743 | if (pad_delta != 0) { |
| 744 | int len; |
| 745 | if (!is_lookup_switch) { |
| 746 | int low = int_at(bci+1+old_pad+4); |
| 747 | int high = int_at(bci+1+old_pad+8); |
| 748 | len = high-low+1 + 3; // 3 for default, hi, lo. |
| 749 | } else { |
| 750 | int npairs = int_at(bci+1+old_pad+4); |
| 751 | len = npairs*2 + 2; // 2 for default, npairs. |
| 752 | } |
| 753 | // Because "relocateCode" does a "changeJumps" loop, |
| 754 | // which parses instructions to determine their length, |
| 755 | // we need to call that before messing with the current |
| 756 | // instruction. Since it may also overwrite the current |
| 757 | // instruction when moving down, remember the possibly |
| 758 | // overwritten part. |
| 759 | |
| 760 | // Move the code following the instruction... |
| 761 | if (!relocate_code(bci, ilen, pad_delta)) return false; |
| 762 | |
| 763 | if (pad_delta < 0) { |
| 764 | // Move the shrunken instruction down. |
| 765 | memmove(addr_at(bci + 1 + new_pad), |
| 766 | addr_at(bci + 1 + old_pad), |
| 767 | len * 4 + pad_delta); |
| 768 | memmove(addr_at(bci + 1 + new_pad + len*4 + pad_delta), |
| 769 | _overwrite, -pad_delta); |
| 770 | } else { |
| 771 | assert(pad_delta > 0, "check"); |
| 772 | // Move the expanded instruction up. |
| 773 | memmove(addr_at(bci +1 + new_pad), |
| 774 | addr_at(bci +1 + old_pad), |
| 775 | len * 4); |
Keith McGuigan | c340115 | 2010-10-21 10:10:23 -0400 | [diff] [blame] | 776 | memset(addr_at(bci + 1), 0, new_pad); // pad must be 0 |
J. Duke | 8153779 | 2007-12-01 00:00:00 +0000 | [diff] [blame] | 777 | } |
| 778 | } |
| 779 | return true; |
| 780 | } |