Sun, 02 Mar 2008 16:10:12 -0800
6557851: CMS: ergonomics defaults are not set with FLAG_SET_ERGO
Summary: Default values set by cms ergonomics are set with FLAG_SET_DEFAULT so down stream the values look like the default values and affect how later parameters are set. Set these values with FLAG_SET_ERGO instead and adjust how later parameters are interpreted.
Reviewed-by: iveresov, apetrusenko, pbk, ysr
duke@435 | 1 | /* |
duke@435 | 2 | * Copyright 1997-2005 Sun Microsystems, Inc. All Rights Reserved. |
duke@435 | 3 | * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
duke@435 | 4 | * |
duke@435 | 5 | * This code is free software; you can redistribute it and/or modify it |
duke@435 | 6 | * under the terms of the GNU General Public License version 2 only, as |
duke@435 | 7 | * published by the Free Software Foundation. |
duke@435 | 8 | * |
duke@435 | 9 | * This code is distributed in the hope that it will be useful, but WITHOUT |
duke@435 | 10 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
duke@435 | 11 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
duke@435 | 12 | * version 2 for more details (a copy is included in the LICENSE file that |
duke@435 | 13 | * accompanied this code). |
duke@435 | 14 | * |
duke@435 | 15 | * You should have received a copy of the GNU General Public License version |
duke@435 | 16 | * 2 along with this work; if not, write to the Free Software Foundation, |
duke@435 | 17 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
duke@435 | 18 | * |
duke@435 | 19 | * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, |
duke@435 | 20 | * CA 95054 USA or visit www.sun.com if you need additional information or |
duke@435 | 21 | * have any questions. |
duke@435 | 22 | * |
duke@435 | 23 | */ |
duke@435 | 24 | |
duke@435 | 25 | # include "incls/_precompiled.incl" |
duke@435 | 26 | # include "incls/_relocator.cpp.incl" |
duke@435 | 27 | |
duke@435 | 28 | #define MAX_METHOD_LENGTH 65535 |
duke@435 | 29 | |
duke@435 | 30 | #define MAX_SHORT ((1 << 15) - 1) |
duke@435 | 31 | #define MIN_SHORT (- (1 << 15)) |
duke@435 | 32 | |
duke@435 | 33 | // Encapsulates a code change request. There are 3 types. |
duke@435 | 34 | // General instruction, jump instruction, and table/lookup switches |
duke@435 | 35 | // |
duke@435 | 36 | class ChangeItem : public ResourceObj { |
duke@435 | 37 | int _bci; |
duke@435 | 38 | public: |
duke@435 | 39 | ChangeItem(int bci) { _bci = bci; } |
duke@435 | 40 | virtual bool handle_code_change(Relocator *r) = 0; |
duke@435 | 41 | |
duke@435 | 42 | // type info |
duke@435 | 43 | virtual bool is_widen() { return false; } |
duke@435 | 44 | virtual bool is_jump_widen() { return false; } |
duke@435 | 45 | virtual bool is_switch_pad() { return false; } |
duke@435 | 46 | |
duke@435 | 47 | // accessors |
duke@435 | 48 | int bci() { return _bci; } |
duke@435 | 49 | void relocate(int break_bci, int delta) { if (_bci > break_bci) { _bci += delta; } } |
duke@435 | 50 | |
duke@435 | 51 | virtual bool adjust(int bci, int delta) { return false; } |
duke@435 | 52 | |
duke@435 | 53 | // debug |
duke@435 | 54 | virtual void print() = 0; |
duke@435 | 55 | }; |
duke@435 | 56 | |
duke@435 | 57 | class ChangeWiden : public ChangeItem { |
duke@435 | 58 | int _new_ilen; // New length of instruction at bci |
duke@435 | 59 | u_char* _inst_buffer; // New bytecodes |
duke@435 | 60 | public: |
duke@435 | 61 | ChangeWiden(int bci, int new_ilen, u_char* inst_buffer) : ChangeItem(bci) { |
duke@435 | 62 | _new_ilen = new_ilen; |
duke@435 | 63 | _inst_buffer = inst_buffer; |
duke@435 | 64 | } |
duke@435 | 65 | |
duke@435 | 66 | // Callback to do instruction |
duke@435 | 67 | bool handle_code_change(Relocator *r) { return r->handle_widen(bci(), _new_ilen, _inst_buffer); }; |
duke@435 | 68 | |
duke@435 | 69 | bool is_widen() { return true; } |
duke@435 | 70 | |
duke@435 | 71 | void print() { tty->print_cr("ChangeWiden. bci: %d New_ilen: %d", bci(), _new_ilen); } |
duke@435 | 72 | }; |
duke@435 | 73 | |
duke@435 | 74 | class ChangeJumpWiden : public ChangeItem { |
duke@435 | 75 | int _delta; // New length of instruction at bci |
duke@435 | 76 | public: |
duke@435 | 77 | ChangeJumpWiden(int bci, int delta) : ChangeItem(bci) { _delta = delta; } |
duke@435 | 78 | |
duke@435 | 79 | // Callback to do instruction |
duke@435 | 80 | bool handle_code_change(Relocator *r) { return r->handle_jump_widen(bci(), _delta); }; |
duke@435 | 81 | |
duke@435 | 82 | bool is_jump_widen() { return true; } |
duke@435 | 83 | |
duke@435 | 84 | // If the bci matches, adjust the delta in the change jump request. |
duke@435 | 85 | bool adjust(int jump_bci, int delta) { |
duke@435 | 86 | if (bci() == jump_bci) { |
duke@435 | 87 | if (_delta > 0) |
duke@435 | 88 | _delta += delta; |
duke@435 | 89 | else |
duke@435 | 90 | _delta -= delta; |
duke@435 | 91 | return true; |
duke@435 | 92 | } |
duke@435 | 93 | return false; |
duke@435 | 94 | } |
duke@435 | 95 | |
duke@435 | 96 | void print() { tty->print_cr("ChangeJumpWiden. bci: %d Delta: %d", bci(), _delta); } |
duke@435 | 97 | }; |
duke@435 | 98 | |
duke@435 | 99 | class ChangeSwitchPad : public ChangeItem { |
duke@435 | 100 | int _padding; |
duke@435 | 101 | bool _is_lookup_switch; |
duke@435 | 102 | public: |
duke@435 | 103 | ChangeSwitchPad(int bci, int padding, bool is_lookup_switch) : ChangeItem(bci) { |
duke@435 | 104 | _padding = padding; |
duke@435 | 105 | _is_lookup_switch = is_lookup_switch; |
duke@435 | 106 | } |
duke@435 | 107 | |
duke@435 | 108 | // Callback to do instruction |
duke@435 | 109 | bool handle_code_change(Relocator *r) { return r->handle_switch_pad(bci(), _padding, _is_lookup_switch); }; |
duke@435 | 110 | |
duke@435 | 111 | bool is_switch_pad() { return true; } |
duke@435 | 112 | int padding() { return _padding; } |
duke@435 | 113 | bool is_lookup_switch() { return _is_lookup_switch; } |
duke@435 | 114 | |
duke@435 | 115 | void print() { tty->print_cr("ChangeSwitchPad. bci: %d Padding: %d IsLookupSwitch: %d", bci(), _padding, _is_lookup_switch); } |
duke@435 | 116 | }; |
duke@435 | 117 | |
duke@435 | 118 | //----------------------------------------------------------------------------------------------------------- |
duke@435 | 119 | // Relocator code |
duke@435 | 120 | |
duke@435 | 121 | Relocator::Relocator(methodHandle m, RelocatorListener* listener) { |
duke@435 | 122 | set_method(m); |
duke@435 | 123 | set_code_length(method()->code_size()); |
duke@435 | 124 | set_code_array(NULL); |
duke@435 | 125 | // Allocate code array and copy bytecodes |
duke@435 | 126 | if (!expand_code_array(0)) { |
duke@435 | 127 | // Should have at least MAX_METHOD_LENGTH available or the verifier |
duke@435 | 128 | // would have failed. |
duke@435 | 129 | ShouldNotReachHere(); |
duke@435 | 130 | } |
duke@435 | 131 | set_compressed_line_number_table(NULL); |
duke@435 | 132 | set_compressed_line_number_table_size(0); |
duke@435 | 133 | _listener = listener; |
duke@435 | 134 | } |
duke@435 | 135 | |
duke@435 | 136 | // size is the new size of the instruction at bci. Hence, if size is less than the current |
duke@435 | 137 | // instruction sice, we will shrink the code. |
duke@435 | 138 | methodHandle Relocator::insert_space_at(int bci, int size, u_char inst_buffer[], TRAPS) { |
duke@435 | 139 | _changes = new GrowableArray<ChangeItem*> (10); |
duke@435 | 140 | _changes->push(new ChangeWiden(bci, size, inst_buffer)); |
duke@435 | 141 | |
duke@435 | 142 | if (TraceRelocator) { |
duke@435 | 143 | tty->print_cr("Space at: %d Size: %d", bci, size); |
duke@435 | 144 | _method->print(); |
duke@435 | 145 | _method->print_codes(); |
duke@435 | 146 | tty->print_cr("-------------------------------------------------"); |
duke@435 | 147 | } |
duke@435 | 148 | |
duke@435 | 149 | if (!handle_code_changes()) return methodHandle(); |
duke@435 | 150 | |
duke@435 | 151 | // Construct the new method |
duke@435 | 152 | methodHandle new_method = methodOopDesc::clone_with_new_data(method(), |
duke@435 | 153 | code_array(), code_length(), |
duke@435 | 154 | compressed_line_number_table(), |
duke@435 | 155 | compressed_line_number_table_size(), |
duke@435 | 156 | CHECK_(methodHandle())); |
duke@435 | 157 | set_method(new_method); |
duke@435 | 158 | |
duke@435 | 159 | if (TraceRelocator) { |
duke@435 | 160 | tty->print_cr("-------------------------------------------------"); |
duke@435 | 161 | tty->print_cr("new method"); |
duke@435 | 162 | _method->print_codes(); |
duke@435 | 163 | } |
duke@435 | 164 | |
duke@435 | 165 | return new_method; |
duke@435 | 166 | } |
duke@435 | 167 | |
duke@435 | 168 | |
duke@435 | 169 | bool Relocator::handle_code_changes() { |
duke@435 | 170 | assert(_changes != NULL, "changes vector must be initialized"); |
duke@435 | 171 | |
duke@435 | 172 | while (!_changes->is_empty()) { |
duke@435 | 173 | // Inv: everything is aligned. |
duke@435 | 174 | ChangeItem* ci = _changes->first(); |
duke@435 | 175 | |
duke@435 | 176 | if (TraceRelocator) { |
duke@435 | 177 | ci->print(); |
duke@435 | 178 | } |
duke@435 | 179 | |
duke@435 | 180 | // Execute operation |
duke@435 | 181 | if (!ci->handle_code_change(this)) return false; |
duke@435 | 182 | |
duke@435 | 183 | // Shuffel items up |
duke@435 | 184 | for (int index = 1; index < _changes->length(); index++) { |
duke@435 | 185 | _changes->at_put(index-1, _changes->at(index)); |
duke@435 | 186 | } |
duke@435 | 187 | _changes->pop(); |
duke@435 | 188 | } |
duke@435 | 189 | return true; |
duke@435 | 190 | } |
duke@435 | 191 | |
duke@435 | 192 | |
duke@435 | 193 | bool Relocator::is_opcode_lookupswitch(Bytecodes::Code bc) { |
duke@435 | 194 | switch (bc) { |
duke@435 | 195 | case Bytecodes::_tableswitch: return false; |
duke@435 | 196 | case Bytecodes::_lookupswitch: // not rewritten on ia64 |
duke@435 | 197 | case Bytecodes::_fast_linearswitch: // rewritten _lookupswitch |
duke@435 | 198 | case Bytecodes::_fast_binaryswitch: return true; // rewritten _lookupswitch |
duke@435 | 199 | default: ShouldNotReachHere(); |
duke@435 | 200 | } |
duke@435 | 201 | return true; // dummy |
duke@435 | 202 | } |
duke@435 | 203 | |
duke@435 | 204 | // We need a special instruction size method, since lookupswitches and tableswitches might not be |
duke@435 | 205 | // properly alligned during relocation |
duke@435 | 206 | int Relocator::rc_instr_len(int bci) { |
duke@435 | 207 | Bytecodes::Code bc= code_at(bci); |
duke@435 | 208 | switch (bc) { |
duke@435 | 209 | // In the case of switch instructions, see if we have the original |
duke@435 | 210 | // padding recorded. |
duke@435 | 211 | case Bytecodes::_tableswitch: |
duke@435 | 212 | case Bytecodes::_lookupswitch: |
duke@435 | 213 | case Bytecodes::_fast_linearswitch: |
duke@435 | 214 | case Bytecodes::_fast_binaryswitch: |
duke@435 | 215 | { |
duke@435 | 216 | int pad = get_orig_switch_pad(bci, is_opcode_lookupswitch(bc)); |
duke@435 | 217 | if (pad == -1) { |
duke@435 | 218 | return instruction_length_at(bci); |
duke@435 | 219 | } |
duke@435 | 220 | // Otherwise, depends on the switch type. |
duke@435 | 221 | switch (bc) { |
duke@435 | 222 | case Bytecodes::_tableswitch: { |
duke@435 | 223 | int lo = int_at(bci + 1 + pad + 4 * 1); |
duke@435 | 224 | int hi = int_at(bci + 1 + pad + 4 * 2); |
duke@435 | 225 | int n = hi - lo + 1; |
duke@435 | 226 | return 1 + pad + 4*(3 + n); |
duke@435 | 227 | } |
duke@435 | 228 | case Bytecodes::_lookupswitch: |
duke@435 | 229 | case Bytecodes::_fast_linearswitch: |
duke@435 | 230 | case Bytecodes::_fast_binaryswitch: { |
duke@435 | 231 | int npairs = int_at(bci + 1 + pad + 4 * 1); |
duke@435 | 232 | return 1 + pad + 4*(2 + 2*npairs); |
duke@435 | 233 | } |
duke@435 | 234 | default: |
duke@435 | 235 | ShouldNotReachHere(); |
duke@435 | 236 | } |
duke@435 | 237 | } |
duke@435 | 238 | } |
duke@435 | 239 | return instruction_length_at(bci); |
duke@435 | 240 | } |
duke@435 | 241 | |
duke@435 | 242 | // If a change item is recorded for "pc", with type "ct", returns the |
duke@435 | 243 | // associated padding, else -1. |
duke@435 | 244 | int Relocator::get_orig_switch_pad(int bci, bool is_lookup_switch) { |
duke@435 | 245 | for (int k = 0; k < _changes->length(); k++) { |
duke@435 | 246 | ChangeItem* ci = _changes->at(k); |
duke@435 | 247 | if (ci->is_switch_pad()) { |
duke@435 | 248 | ChangeSwitchPad* csp = (ChangeSwitchPad*)ci; |
duke@435 | 249 | if (csp->is_lookup_switch() == is_lookup_switch && csp->bci() == bci) { |
duke@435 | 250 | return csp->padding(); |
duke@435 | 251 | } |
duke@435 | 252 | } |
duke@435 | 253 | } |
duke@435 | 254 | return -1; |
duke@435 | 255 | } |
duke@435 | 256 | |
duke@435 | 257 | |
duke@435 | 258 | // Push a ChangeJumpWiden if it doesn't already exist on the work queue, |
duke@435 | 259 | // otherwise adjust the item already there by delta. The calculation for |
duke@435 | 260 | // new_delta is wrong for this because it uses the offset stored in the |
duke@435 | 261 | // code stream itself which wasn't fixed when item was pushed on the work queue. |
duke@435 | 262 | void Relocator::push_jump_widen(int bci, int delta, int new_delta) { |
duke@435 | 263 | for (int j = 0; j < _changes->length(); j++) { |
duke@435 | 264 | ChangeItem* ci = _changes->at(j); |
duke@435 | 265 | if (ci->adjust(bci, delta)) return; |
duke@435 | 266 | } |
duke@435 | 267 | _changes->push(new ChangeJumpWiden(bci, new_delta)); |
duke@435 | 268 | } |
duke@435 | 269 | |
duke@435 | 270 | |
duke@435 | 271 | // The current instruction of "c" is a jump; one of its offset starts |
duke@435 | 272 | // at "offset" and is a short if "isShort" is "TRUE", |
duke@435 | 273 | // and an integer otherwise. If the jump crosses "breakPC", change |
duke@435 | 274 | // the span of the jump by "delta". |
duke@435 | 275 | void Relocator::change_jump(int bci, int offset, bool is_short, int break_bci, int delta) { |
duke@435 | 276 | int bci_delta = (is_short) ? short_at(offset) : int_at(offset); |
duke@435 | 277 | int targ = bci + bci_delta; |
duke@435 | 278 | |
duke@435 | 279 | if ((bci <= break_bci && targ > break_bci) || |
duke@435 | 280 | (bci > break_bci && targ <= break_bci)) { |
duke@435 | 281 | int new_delta; |
duke@435 | 282 | if (bci_delta > 0) |
duke@435 | 283 | new_delta = bci_delta + delta; |
duke@435 | 284 | else |
duke@435 | 285 | new_delta = bci_delta - delta; |
duke@435 | 286 | |
duke@435 | 287 | if (is_short && ((new_delta > MAX_SHORT) || new_delta < MIN_SHORT)) { |
duke@435 | 288 | push_jump_widen(bci, delta, new_delta); |
duke@435 | 289 | } else if (is_short) { |
duke@435 | 290 | short_at_put(offset, new_delta); |
duke@435 | 291 | } else { |
duke@435 | 292 | int_at_put(offset, new_delta); |
duke@435 | 293 | } |
duke@435 | 294 | } |
duke@435 | 295 | } |
duke@435 | 296 | |
duke@435 | 297 | |
duke@435 | 298 | // Changes all jumps crossing "break_bci" by "delta". May enqueue things |
duke@435 | 299 | // on "rc->changes" |
duke@435 | 300 | void Relocator::change_jumps(int break_bci, int delta) { |
duke@435 | 301 | int bci = 0; |
duke@435 | 302 | Bytecodes::Code bc; |
duke@435 | 303 | // Now, adjust any affected instructions. |
duke@435 | 304 | while (bci < code_length()) { |
duke@435 | 305 | switch (bc= code_at(bci)) { |
duke@435 | 306 | case Bytecodes::_ifeq: |
duke@435 | 307 | case Bytecodes::_ifne: |
duke@435 | 308 | case Bytecodes::_iflt: |
duke@435 | 309 | case Bytecodes::_ifge: |
duke@435 | 310 | case Bytecodes::_ifgt: |
duke@435 | 311 | case Bytecodes::_ifle: |
duke@435 | 312 | case Bytecodes::_if_icmpeq: |
duke@435 | 313 | case Bytecodes::_if_icmpne: |
duke@435 | 314 | case Bytecodes::_if_icmplt: |
duke@435 | 315 | case Bytecodes::_if_icmpge: |
duke@435 | 316 | case Bytecodes::_if_icmpgt: |
duke@435 | 317 | case Bytecodes::_if_icmple: |
duke@435 | 318 | case Bytecodes::_if_acmpeq: |
duke@435 | 319 | case Bytecodes::_if_acmpne: |
duke@435 | 320 | case Bytecodes::_ifnull: |
duke@435 | 321 | case Bytecodes::_ifnonnull: |
duke@435 | 322 | case Bytecodes::_goto: |
duke@435 | 323 | case Bytecodes::_jsr: |
duke@435 | 324 | change_jump(bci, bci+1, true, break_bci, delta); |
duke@435 | 325 | break; |
duke@435 | 326 | case Bytecodes::_goto_w: |
duke@435 | 327 | case Bytecodes::_jsr_w: |
duke@435 | 328 | change_jump(bci, bci+1, false, break_bci, delta); |
duke@435 | 329 | break; |
duke@435 | 330 | case Bytecodes::_tableswitch: |
duke@435 | 331 | case Bytecodes::_lookupswitch: |
duke@435 | 332 | case Bytecodes::_fast_linearswitch: |
duke@435 | 333 | case Bytecodes::_fast_binaryswitch: { |
duke@435 | 334 | int recPad = get_orig_switch_pad(bci, (bc != Bytecodes::_tableswitch)); |
duke@435 | 335 | int oldPad = (recPad != -1) ? recPad : align(bci+1) - (bci+1); |
duke@435 | 336 | if (bci > break_bci) { |
duke@435 | 337 | int new_bci = bci + delta; |
duke@435 | 338 | int newPad = align(new_bci+1) - (new_bci+1); |
duke@435 | 339 | // Do we need to check the padding? |
duke@435 | 340 | if (newPad != oldPad) { |
duke@435 | 341 | if (recPad == -1) { |
duke@435 | 342 | _changes->push(new ChangeSwitchPad(bci, oldPad, (bc != Bytecodes::_tableswitch))); |
duke@435 | 343 | } |
duke@435 | 344 | } |
duke@435 | 345 | } |
duke@435 | 346 | |
duke@435 | 347 | // Then the rest, which depend on the kind of switch. |
duke@435 | 348 | switch (bc) { |
duke@435 | 349 | case Bytecodes::_tableswitch: { |
duke@435 | 350 | change_jump(bci, bci +1 + oldPad, false, break_bci, delta); |
duke@435 | 351 | // We cannot use the Bytecode_tableswitch abstraction, since the padding might not be correct. |
duke@435 | 352 | int lo = int_at(bci + 1 + oldPad + 4 * 1); |
duke@435 | 353 | int hi = int_at(bci + 1 + oldPad + 4 * 2); |
duke@435 | 354 | int n = hi - lo + 1; |
duke@435 | 355 | for (int k = 0; k < n; k++) { |
duke@435 | 356 | change_jump(bci, bci +1 + oldPad + 4*(k+3), false, break_bci, delta); |
duke@435 | 357 | } |
duke@435 | 358 | // Special next-bci calculation here... |
duke@435 | 359 | bci += 1 + oldPad + (n+3)*4; |
duke@435 | 360 | continue; |
duke@435 | 361 | } |
duke@435 | 362 | case Bytecodes::_lookupswitch: |
duke@435 | 363 | case Bytecodes::_fast_linearswitch: |
duke@435 | 364 | case Bytecodes::_fast_binaryswitch: { |
duke@435 | 365 | change_jump(bci, bci +1 + oldPad, false, break_bci, delta); |
duke@435 | 366 | // We cannot use the Bytecode_lookupswitch abstraction, since the padding might not be correct. |
duke@435 | 367 | int npairs = int_at(bci + 1 + oldPad + 4 * 1); |
duke@435 | 368 | for (int k = 0; k < npairs; k++) { |
duke@435 | 369 | change_jump(bci, bci + 1 + oldPad + 4*(2 + 2*k + 1), false, break_bci, delta); |
duke@435 | 370 | } |
duke@435 | 371 | /* Special next-bci calculation here... */ |
duke@435 | 372 | bci += 1 + oldPad + (2 + (npairs*2))*4; |
duke@435 | 373 | continue; |
duke@435 | 374 | } |
duke@435 | 375 | default: |
duke@435 | 376 | ShouldNotReachHere(); |
duke@435 | 377 | } |
duke@435 | 378 | } |
duke@435 | 379 | default: |
duke@435 | 380 | break; |
duke@435 | 381 | } |
duke@435 | 382 | bci += rc_instr_len(bci); |
duke@435 | 383 | } |
duke@435 | 384 | } |
duke@435 | 385 | |
duke@435 | 386 | // The width of instruction at "pc" is changing by "delta". Adjust the |
duke@435 | 387 | // exception table, if any, of "rc->mb". |
duke@435 | 388 | void Relocator::adjust_exception_table(int bci, int delta) { |
duke@435 | 389 | typeArrayOop table = method()->exception_table(); |
duke@435 | 390 | for (int index = 0; index < table->length(); index +=4) { |
duke@435 | 391 | if (table->int_at(index) > bci) { |
duke@435 | 392 | table->int_at_put(index+0, table->int_at(index+0) + delta); |
duke@435 | 393 | table->int_at_put(index+1, table->int_at(index+1) + delta); |
duke@435 | 394 | } else if (bci < table->int_at(index+1)) { |
duke@435 | 395 | table->int_at_put(index+1, table->int_at(index+1) + delta); |
duke@435 | 396 | } |
duke@435 | 397 | if (table->int_at(index+2) > bci) |
duke@435 | 398 | table->int_at_put(index+2, table->int_at(index+2) + delta); |
duke@435 | 399 | } |
duke@435 | 400 | } |
duke@435 | 401 | |
duke@435 | 402 | |
duke@435 | 403 | // The width of instruction at "bci" is changing by "delta". Adjust the line number table. |
duke@435 | 404 | void Relocator::adjust_line_no_table(int bci, int delta) { |
duke@435 | 405 | if (method()->has_linenumber_table()) { |
duke@435 | 406 | CompressedLineNumberReadStream reader(method()->compressed_linenumber_table()); |
duke@435 | 407 | CompressedLineNumberWriteStream writer(64); // plenty big for most line number tables |
duke@435 | 408 | while (reader.read_pair()) { |
duke@435 | 409 | int adjustment = (reader.bci() > bci) ? delta : 0; |
duke@435 | 410 | writer.write_pair(reader.bci() + adjustment, reader.line()); |
duke@435 | 411 | } |
duke@435 | 412 | writer.write_terminator(); |
duke@435 | 413 | set_compressed_line_number_table(writer.buffer()); |
duke@435 | 414 | set_compressed_line_number_table_size(writer.position()); |
duke@435 | 415 | } |
duke@435 | 416 | } |
duke@435 | 417 | |
duke@435 | 418 | |
duke@435 | 419 | // The width of instruction at "bci" is changing by "delta". Adjust the local variable table. |
duke@435 | 420 | void Relocator::adjust_local_var_table(int bci, int delta) { |
duke@435 | 421 | int localvariable_table_length = method()->localvariable_table_length(); |
duke@435 | 422 | if (localvariable_table_length > 0) { |
duke@435 | 423 | LocalVariableTableElement* table = method()->localvariable_table_start(); |
duke@435 | 424 | for (int i = 0; i < localvariable_table_length; i++) { |
duke@435 | 425 | u2 current_bci = table[i].start_bci; |
duke@435 | 426 | if (current_bci > bci) { |
duke@435 | 427 | table[i].start_bci = current_bci + delta; |
duke@435 | 428 | } else { |
duke@435 | 429 | u2 current_length = table[i].length; |
duke@435 | 430 | if (current_bci + current_length > bci) { |
duke@435 | 431 | table[i].length = current_length + delta; |
duke@435 | 432 | } |
duke@435 | 433 | } |
duke@435 | 434 | } |
duke@435 | 435 | } |
duke@435 | 436 | } |
duke@435 | 437 | |
duke@435 | 438 | |
duke@435 | 439 | bool Relocator::expand_code_array(int delta) { |
duke@435 | 440 | int length = MAX2(code_length() + delta, code_length() * (100+code_slop_pct()) / 100); |
duke@435 | 441 | |
duke@435 | 442 | if (length > MAX_METHOD_LENGTH) { |
duke@435 | 443 | if (delta == 0 && code_length() <= MAX_METHOD_LENGTH) { |
duke@435 | 444 | length = MAX_METHOD_LENGTH; |
duke@435 | 445 | } else { |
duke@435 | 446 | return false; |
duke@435 | 447 | } |
duke@435 | 448 | } |
duke@435 | 449 | |
duke@435 | 450 | unsigned char* new_code_array = NEW_RESOURCE_ARRAY(unsigned char, length); |
duke@435 | 451 | if (!new_code_array) return false; |
duke@435 | 452 | |
duke@435 | 453 | // Expanding current array |
duke@435 | 454 | if (code_array() != NULL) { |
duke@435 | 455 | memcpy(new_code_array, code_array(), code_length()); |
duke@435 | 456 | } else { |
duke@435 | 457 | // Initial copy. Copy directly from methodOop |
duke@435 | 458 | memcpy(new_code_array, method()->code_base(), code_length()); |
duke@435 | 459 | } |
duke@435 | 460 | |
duke@435 | 461 | set_code_array(new_code_array); |
duke@435 | 462 | set_code_array_length(length); |
duke@435 | 463 | |
duke@435 | 464 | return true; |
duke@435 | 465 | } |
duke@435 | 466 | |
duke@435 | 467 | |
duke@435 | 468 | // The instruction at "bci", whose size is "ilen", is changing size by |
duke@435 | 469 | // "delta". Reallocate, move code, recalculate jumps, and enqueue |
duke@435 | 470 | // change items as necessary. |
duke@435 | 471 | bool Relocator::relocate_code(int bci, int ilen, int delta) { |
duke@435 | 472 | int next_bci = bci + ilen; |
duke@435 | 473 | if (delta > 0 && code_length() + delta > code_array_length()) { |
duke@435 | 474 | // Expand allocated code space, if necessary. |
duke@435 | 475 | if (!expand_code_array(delta)) { |
duke@435 | 476 | return false; |
duke@435 | 477 | } |
duke@435 | 478 | } |
duke@435 | 479 | |
duke@435 | 480 | // We require 4-byte alignment of code arrays. |
duke@435 | 481 | assert(((intptr_t)code_array() & 3) == 0, "check code alignment"); |
duke@435 | 482 | // Change jumps before doing the copying; this routine requires aligned switches. |
duke@435 | 483 | change_jumps(bci, delta); |
duke@435 | 484 | |
duke@435 | 485 | // In case we have shrunken a tableswitch/lookupswitch statement, we store the last |
duke@435 | 486 | // bytes that get overwritten. We have to copy the bytes after the change_jumps method |
duke@435 | 487 | // has been called, since it is likly to update last offset in a tableswitch/lookupswitch |
duke@435 | 488 | if (delta < 0) { |
duke@435 | 489 | assert(delta>=-3, "we cannot overwrite more than 3 bytes"); |
duke@435 | 490 | memcpy(_overwrite, addr_at(bci + ilen + delta), -delta); |
duke@435 | 491 | } |
duke@435 | 492 | |
duke@435 | 493 | memmove(addr_at(next_bci + delta), addr_at(next_bci), code_length() - next_bci); |
duke@435 | 494 | set_code_length(code_length() + delta); |
duke@435 | 495 | // Also adjust exception tables... |
duke@435 | 496 | adjust_exception_table(bci, delta); |
duke@435 | 497 | // Line number tables... |
duke@435 | 498 | adjust_line_no_table(bci, delta); |
duke@435 | 499 | // And local variable table... |
duke@435 | 500 | adjust_local_var_table(bci, delta); |
duke@435 | 501 | |
duke@435 | 502 | // Relocate the pending change stack... |
duke@435 | 503 | for (int j = 0; j < _changes->length(); j++) { |
duke@435 | 504 | ChangeItem* ci = _changes->at(j); |
duke@435 | 505 | ci->relocate(bci, delta); |
duke@435 | 506 | } |
duke@435 | 507 | |
duke@435 | 508 | // Notify any listeners about code relocation |
duke@435 | 509 | notify(bci, delta, code_length()); |
duke@435 | 510 | |
duke@435 | 511 | return true; |
duke@435 | 512 | } |
duke@435 | 513 | |
duke@435 | 514 | // relocate a general instruction. Called by ChangeWiden class |
duke@435 | 515 | bool Relocator::handle_widen(int bci, int new_ilen, u_char inst_buffer[]) { |
duke@435 | 516 | int ilen = rc_instr_len(bci); |
duke@435 | 517 | if (!relocate_code(bci, ilen, new_ilen - ilen)) |
duke@435 | 518 | return false; |
duke@435 | 519 | |
duke@435 | 520 | // Insert new bytecode(s) |
duke@435 | 521 | for(int k = 0; k < new_ilen; k++) { |
duke@435 | 522 | code_at_put(bci + k, (Bytecodes::Code)inst_buffer[k]); |
duke@435 | 523 | } |
duke@435 | 524 | |
duke@435 | 525 | return true; |
duke@435 | 526 | } |
duke@435 | 527 | |
duke@435 | 528 | // handle jump_widen instruction. Called be ChangeJumpWiden class |
duke@435 | 529 | bool Relocator::handle_jump_widen(int bci, int delta) { |
duke@435 | 530 | int ilen = rc_instr_len(bci); |
duke@435 | 531 | |
duke@435 | 532 | Bytecodes::Code bc = code_at(bci); |
duke@435 | 533 | switch (bc) { |
duke@435 | 534 | case Bytecodes::_ifeq: |
duke@435 | 535 | case Bytecodes::_ifne: |
duke@435 | 536 | case Bytecodes::_iflt: |
duke@435 | 537 | case Bytecodes::_ifge: |
duke@435 | 538 | case Bytecodes::_ifgt: |
duke@435 | 539 | case Bytecodes::_ifle: |
duke@435 | 540 | case Bytecodes::_if_icmpeq: |
duke@435 | 541 | case Bytecodes::_if_icmpne: |
duke@435 | 542 | case Bytecodes::_if_icmplt: |
duke@435 | 543 | case Bytecodes::_if_icmpge: |
duke@435 | 544 | case Bytecodes::_if_icmpgt: |
duke@435 | 545 | case Bytecodes::_if_icmple: |
duke@435 | 546 | case Bytecodes::_if_acmpeq: |
duke@435 | 547 | case Bytecodes::_if_acmpne: |
duke@435 | 548 | case Bytecodes::_ifnull: |
duke@435 | 549 | case Bytecodes::_ifnonnull: { |
duke@435 | 550 | const int goto_length = Bytecodes::length_for(Bytecodes::_goto); |
duke@435 | 551 | |
duke@435 | 552 | // If 'if' points to the next bytecode after goto, it's already handled. |
duke@435 | 553 | // it shouldn't be. |
duke@435 | 554 | assert (short_at(bci+1) != ilen+goto_length, "if relocation already handled"); |
duke@435 | 555 | assert(ilen == 3, "check length"); |
duke@435 | 556 | |
duke@435 | 557 | // Convert to 0 if <cond> goto 6 |
duke@435 | 558 | // 3 _goto 11 |
duke@435 | 559 | // 6 _goto_w <wide delta offset> |
duke@435 | 560 | // 11 <else code> |
duke@435 | 561 | const int goto_w_length = Bytecodes::length_for(Bytecodes::_goto_w); |
duke@435 | 562 | const int add_bci = goto_length + goto_w_length; |
duke@435 | 563 | |
duke@435 | 564 | if (!relocate_code(bci, 3, /*delta*/add_bci)) return false; |
duke@435 | 565 | |
duke@435 | 566 | // if bytecode points to goto_w instruction |
duke@435 | 567 | short_at_put(bci + 1, ilen + goto_length); |
duke@435 | 568 | |
duke@435 | 569 | int cbci = bci + ilen; |
duke@435 | 570 | // goto around |
duke@435 | 571 | code_at_put(cbci, Bytecodes::_goto); |
duke@435 | 572 | short_at_put(cbci + 1, add_bci); |
duke@435 | 573 | // goto_w <wide delta> |
duke@435 | 574 | cbci = cbci + goto_length; |
duke@435 | 575 | code_at_put(cbci, Bytecodes::_goto_w); |
duke@435 | 576 | if (delta > 0) { |
duke@435 | 577 | delta += 2; // goto_w is 2 bytes more than "if" code |
duke@435 | 578 | } else { |
duke@435 | 579 | delta -= ilen+goto_length; // branch starts at goto_w offset |
duke@435 | 580 | } |
duke@435 | 581 | int_at_put(cbci + 1, delta); |
duke@435 | 582 | break; |
duke@435 | 583 | |
duke@435 | 584 | } |
duke@435 | 585 | case Bytecodes::_goto: |
duke@435 | 586 | case Bytecodes::_jsr: |
duke@435 | 587 | assert(ilen == 3, "check length"); |
duke@435 | 588 | |
duke@435 | 589 | if (!relocate_code(bci, 3, 2)) return false; |
duke@435 | 590 | if (bc == Bytecodes::_goto) |
duke@435 | 591 | code_at_put(bci, Bytecodes::_goto_w); |
duke@435 | 592 | else |
duke@435 | 593 | code_at_put(bci, Bytecodes::_jsr_w); |
duke@435 | 594 | |
duke@435 | 595 | // If it's a forward jump, add 2 for the widening. |
duke@435 | 596 | if (delta > 0) delta += 2; |
duke@435 | 597 | int_at_put(bci + 1, delta); |
duke@435 | 598 | break; |
duke@435 | 599 | |
duke@435 | 600 | default: ShouldNotReachHere(); |
duke@435 | 601 | } |
duke@435 | 602 | |
duke@435 | 603 | return true; |
duke@435 | 604 | } |
duke@435 | 605 | |
duke@435 | 606 | // handle lookup/table switch instructions. Called be ChangeSwitchPad class |
duke@435 | 607 | bool Relocator::handle_switch_pad(int bci, int old_pad, bool is_lookup_switch) { |
duke@435 | 608 | int ilen = rc_instr_len(bci); |
duke@435 | 609 | int new_pad = align(bci+1) - (bci+1); |
duke@435 | 610 | int pad_delta = new_pad - old_pad; |
duke@435 | 611 | if (pad_delta != 0) { |
duke@435 | 612 | int len; |
duke@435 | 613 | if (!is_lookup_switch) { |
duke@435 | 614 | int low = int_at(bci+1+old_pad+4); |
duke@435 | 615 | int high = int_at(bci+1+old_pad+8); |
duke@435 | 616 | len = high-low+1 + 3; // 3 for default, hi, lo. |
duke@435 | 617 | } else { |
duke@435 | 618 | int npairs = int_at(bci+1+old_pad+4); |
duke@435 | 619 | len = npairs*2 + 2; // 2 for default, npairs. |
duke@435 | 620 | } |
duke@435 | 621 | // Because "relocateCode" does a "changeJumps" loop, |
duke@435 | 622 | // which parses instructions to determine their length, |
duke@435 | 623 | // we need to call that before messing with the current |
duke@435 | 624 | // instruction. Since it may also overwrite the current |
duke@435 | 625 | // instruction when moving down, remember the possibly |
duke@435 | 626 | // overwritten part. |
duke@435 | 627 | |
duke@435 | 628 | // Move the code following the instruction... |
duke@435 | 629 | if (!relocate_code(bci, ilen, pad_delta)) return false; |
duke@435 | 630 | |
duke@435 | 631 | if (pad_delta < 0) { |
duke@435 | 632 | // Move the shrunken instruction down. |
duke@435 | 633 | memmove(addr_at(bci + 1 + new_pad), |
duke@435 | 634 | addr_at(bci + 1 + old_pad), |
duke@435 | 635 | len * 4 + pad_delta); |
duke@435 | 636 | memmove(addr_at(bci + 1 + new_pad + len*4 + pad_delta), |
duke@435 | 637 | _overwrite, -pad_delta); |
duke@435 | 638 | } else { |
duke@435 | 639 | assert(pad_delta > 0, "check"); |
duke@435 | 640 | // Move the expanded instruction up. |
duke@435 | 641 | memmove(addr_at(bci +1 + new_pad), |
duke@435 | 642 | addr_at(bci +1 + old_pad), |
duke@435 | 643 | len * 4); |
duke@435 | 644 | } |
duke@435 | 645 | } |
duke@435 | 646 | return true; |
duke@435 | 647 | } |