1 /* 2 * Copyright (c) 1997, 2014, 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 "code/codeCache.hpp" 27 #include "code/compiledIC.hpp" 28 #include "code/nmethod.hpp" 29 #include "code/relocInfo.hpp" 30 #include "memory/resourceArea.hpp" 31 #include "runtime/stubCodeGenerator.hpp" 32 #include "utilities/copy.hpp" 33 34 PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC 35 36 const RelocationHolder RelocationHolder::none; // its type is relocInfo::none 37 38 39 // Implementation of relocInfo 40 41 #ifdef ASSERT 42 relocInfo::relocInfo(relocType t, int off, int f) { 43 assert(t != data_prefix_tag, "cannot build a prefix this way"); 44 assert((t & type_mask) == t, "wrong type"); 45 assert((f & format_mask) == f, "wrong format"); 46 assert(off >= 0 && off < offset_limit(), "offset out off bounds"); 47 assert((off & (offset_unit-1)) == 0, "misaligned offset"); 48 (*this) = relocInfo(t, RAW_BITS, off, f); 49 } 50 #endif 51 52 void relocInfo::initialize(CodeSection* dest, Relocation* reloc) { 53 relocInfo* data = this+1; // here's where the data might go 54 dest->set_locs_end(data); // sync end: the next call may read dest.locs_end 55 reloc->pack_data_to(dest); // maybe write data into locs, advancing locs_end 56 relocInfo* data_limit = dest->locs_end(); 57 if (data_limit > data) { 58 relocInfo suffix = (*this); 59 data_limit = this->finish_prefix((short*) data_limit); 60 // Finish up with the suffix. (Hack note: pack_data_to might edit this.) 61 *data_limit = suffix; 62 dest->set_locs_end(data_limit+1); 63 } 64 } 65 66 relocInfo* relocInfo::finish_prefix(short* prefix_limit) { 67 assert(sizeof(relocInfo) == sizeof(short), "change this code"); 68 short* p = (short*)(this+1); 69 assert(prefix_limit >= p, "must be a valid span of data"); 70 int plen = prefix_limit - p; 71 if (plen == 0) { 72 debug_only(_value = 0xFFFF); 73 return this; // no data: remove self completely 74 } 75 if (plen == 1 && fits_into_immediate(p[0])) { 76 (*this) = immediate_relocInfo(p[0]); // move data inside self 77 return this+1; 78 } 79 // cannot compact, so just update the count and return the limit pointer 80 (*this) = prefix_relocInfo(plen); // write new datalen 81 assert(data() + datalen() == prefix_limit, "pointers must line up"); 82 return (relocInfo*)prefix_limit; 83 } 84 85 86 void relocInfo::set_type(relocType t) { 87 int old_offset = addr_offset(); 88 int old_format = format(); 89 (*this) = relocInfo(t, old_offset, old_format); 90 assert(type()==(int)t, "sanity check"); 91 assert(addr_offset()==old_offset, "sanity check"); 92 assert(format()==old_format, "sanity check"); 93 } 94 95 96 void relocInfo::set_format(int f) { 97 int old_offset = addr_offset(); 98 assert((f & format_mask) == f, "wrong format"); 99 _value = (_value & ~(format_mask << offset_width)) | (f << offset_width); 100 assert(addr_offset()==old_offset, "sanity check"); 101 } 102 103 104 void relocInfo::change_reloc_info_for_address(RelocIterator *itr, address pc, relocType old_type, relocType new_type) { 105 bool found = false; 106 while (itr->next() && !found) { 107 if (itr->addr() == pc) { 108 assert(itr->type()==old_type, "wrong relocInfo type found"); 109 itr->current()->set_type(new_type); 110 found=true; 111 } 112 } 113 assert(found, "no relocInfo found for pc"); 114 } 115 116 117 void relocInfo::remove_reloc_info_for_address(RelocIterator *itr, address pc, relocType old_type) { 118 change_reloc_info_for_address(itr, pc, old_type, none); 119 } 120 121 122 // ---------------------------------------------------------------------------------------------------- 123 // Implementation of RelocIterator 124 125 void RelocIterator::initialize(nmethod* nm, address begin, address limit) { 126 initialize_misc(); 127 128 if (nm == NULL && begin != NULL) { 129 // allow nmethod to be deduced from beginning address 130 CodeBlob* cb = CodeCache::find_blob(begin); 131 nm = cb->as_nmethod_or_null(); 132 } 133 assert(nm != NULL, "must be able to deduce nmethod from other arguments"); 134 135 _code = nm; 136 _current = nm->relocation_begin() - 1; 137 _end = nm->relocation_end(); 138 _addr = nm->content_begin(); 139 140 // Initialize code sections. 141 _section_start[CodeBuffer::SECT_CONSTS] = nm->consts_begin(); 142 _section_start[CodeBuffer::SECT_INSTS ] = nm->insts_begin() ; 143 _section_start[CodeBuffer::SECT_STUBS ] = nm->stub_begin() ; 144 145 _section_end [CodeBuffer::SECT_CONSTS] = nm->consts_end() ; 146 _section_end [CodeBuffer::SECT_INSTS ] = nm->insts_end() ; 147 _section_end [CodeBuffer::SECT_STUBS ] = nm->stub_end() ; 148 149 assert(!has_current(), "just checking"); 150 assert(begin == NULL || begin >= nm->code_begin(), "in bounds"); 151 assert(limit == NULL || limit <= nm->code_end(), "in bounds"); 152 set_limits(begin, limit); 153 } 154 155 156 RelocIterator::RelocIterator(CodeSection* cs, address begin, address limit) { 157 initialize_misc(); 158 159 _current = cs->locs_start()-1; 160 _end = cs->locs_end(); 161 _addr = cs->start(); 162 _code = NULL; // Not cb->blob(); 163 164 CodeBuffer* cb = cs->outer(); 165 assert((int) SECT_LIMIT == CodeBuffer::SECT_LIMIT, "my copy must be equal"); 166 for (int n = (int) CodeBuffer::SECT_FIRST; n < (int) CodeBuffer::SECT_LIMIT; n++) { 167 CodeSection* cs = cb->code_section(n); 168 _section_start[n] = cs->start(); 169 _section_end [n] = cs->end(); 170 } 171 172 assert(!has_current(), "just checking"); 173 174 assert(begin == NULL || begin >= cs->start(), "in bounds"); 175 assert(limit == NULL || limit <= cs->end(), "in bounds"); 176 set_limits(begin, limit); 177 } 178 179 180 enum { indexCardSize = 128 }; 181 struct RelocIndexEntry { 182 jint addr_offset; // offset from header_end of an addr() 183 jint reloc_offset; // offset from header_end of a relocInfo (prefix) 184 }; 185 186 187 bool RelocIterator::addr_in_const() const { 188 const int n = CodeBuffer::SECT_CONSTS; 189 return section_start(n) <= addr() && addr() < section_end(n); 190 } 191 192 193 static inline int num_cards(int code_size) { 194 return (code_size-1) / indexCardSize; 195 } 196 197 198 int RelocIterator::locs_and_index_size(int code_size, int locs_size) { 199 if (!UseRelocIndex) return locs_size; // no index 200 code_size = round_to(code_size, oopSize); 201 locs_size = round_to(locs_size, oopSize); 202 int index_size = num_cards(code_size) * sizeof(RelocIndexEntry); 203 // format of indexed relocs: 204 // relocation_begin: relocInfo ... 205 // index: (addr,reloc#) ... 206 // indexSize :relocation_end 207 return locs_size + index_size + BytesPerInt; 208 } 209 210 211 void RelocIterator::create_index(relocInfo* dest_begin, int dest_count, relocInfo* dest_end) { 212 address relocation_begin = (address)dest_begin; 213 address relocation_end = (address)dest_end; 214 int total_size = relocation_end - relocation_begin; 215 int locs_size = dest_count * sizeof(relocInfo); 216 if (!UseRelocIndex) { 217 Copy::fill_to_bytes(relocation_begin + locs_size, total_size-locs_size, 0); 218 return; 219 } 220 int index_size = total_size - locs_size - BytesPerInt; // find out how much space is left 221 int ncards = index_size / sizeof(RelocIndexEntry); 222 assert(total_size == locs_size + index_size + BytesPerInt, "checkin'"); 223 assert(index_size >= 0 && index_size % sizeof(RelocIndexEntry) == 0, "checkin'"); 224 jint* index_size_addr = (jint*)relocation_end - 1; 225 226 assert(sizeof(jint) == BytesPerInt, "change this code"); 227 228 *index_size_addr = index_size; 229 if (index_size != 0) { 230 assert(index_size > 0, "checkin'"); 231 232 RelocIndexEntry* index = (RelocIndexEntry *)(relocation_begin + locs_size); 233 assert(index == (RelocIndexEntry*)index_size_addr - ncards, "checkin'"); 234 235 // walk over the relocations, and fill in index entries as we go 236 RelocIterator iter; 237 const address initial_addr = NULL; 238 relocInfo* const initial_current = dest_begin - 1; // biased by -1 like elsewhere 239 240 iter._code = NULL; 241 iter._addr = initial_addr; 242 iter._limit = (address)(intptr_t)(ncards * indexCardSize); 243 iter._current = initial_current; 244 iter._end = dest_begin + dest_count; 245 246 int i = 0; 247 address next_card_addr = (address)indexCardSize; 248 int addr_offset = 0; 249 int reloc_offset = 0; 250 while (true) { 251 // Checkpoint the iterator before advancing it. 252 addr_offset = iter._addr - initial_addr; 253 reloc_offset = iter._current - initial_current; 254 if (!iter.next()) break; 255 while (iter.addr() >= next_card_addr) { 256 index[i].addr_offset = addr_offset; 257 index[i].reloc_offset = reloc_offset; 258 i++; 259 next_card_addr += indexCardSize; 260 } 261 } 262 while (i < ncards) { 263 index[i].addr_offset = addr_offset; 264 index[i].reloc_offset = reloc_offset; 265 i++; 266 } 267 } 268 } 269 270 271 void RelocIterator::set_limits(address begin, address limit) { 272 int index_size = 0; 273 if (UseRelocIndex && _code != NULL) { 274 index_size = ((jint*)_end)[-1]; 275 _end = (relocInfo*)( (address)_end - index_size - BytesPerInt ); 276 } 277 278 _limit = limit; 279 280 // the limit affects this next stuff: 281 if (begin != NULL) { 282 #ifdef ASSERT 283 // In ASSERT mode we do not actually use the index, but simply 284 // check that its contents would have led us to the right answer. 285 address addrCheck = _addr; 286 relocInfo* infoCheck = _current; 287 #endif // ASSERT 288 if (index_size > 0) { 289 // skip ahead 290 RelocIndexEntry* index = (RelocIndexEntry*)_end; 291 RelocIndexEntry* index_limit = (RelocIndexEntry*)((address)index + index_size); 292 assert(_addr == _code->code_begin(), "_addr must be unadjusted"); 293 int card = (begin - _addr) / indexCardSize; 294 if (card > 0) { 295 if (index+card-1 < index_limit) index += card-1; 296 else index = index_limit - 1; 297 #ifdef ASSERT 298 addrCheck = _addr + index->addr_offset; 299 infoCheck = _current + index->reloc_offset; 300 #else 301 // Advance the iterator immediately to the last valid state 302 // for the previous card. Calling "next" will then advance 303 // it to the first item on the required card. 304 _addr += index->addr_offset; 305 _current += index->reloc_offset; 306 #endif // ASSERT 307 } 308 } 309 310 relocInfo* backup; 311 address backup_addr; 312 while (true) { 313 backup = _current; 314 backup_addr = _addr; 315 #ifdef ASSERT 316 if (backup == infoCheck) { 317 assert(backup_addr == addrCheck, "must match"); addrCheck = NULL; infoCheck = NULL; 318 } else { 319 assert(addrCheck == NULL || backup_addr <= addrCheck, "must not pass addrCheck"); 320 } 321 #endif // ASSERT 322 if (!next() || addr() >= begin) break; 323 } 324 assert(addrCheck == NULL || addrCheck == backup_addr, "must have matched addrCheck"); 325 assert(infoCheck == NULL || infoCheck == backup, "must have matched infoCheck"); 326 // At this point, either we are at the first matching record, 327 // or else there is no such record, and !has_current(). 328 // In either case, revert to the immediatly preceding state. 329 _current = backup; 330 _addr = backup_addr; 331 set_has_current(false); 332 } 333 } 334 335 336 void RelocIterator::set_limit(address limit) { 337 address code_end = (address)code() + code()->size(); 338 assert(limit == NULL || limit <= code_end, "in bounds"); 339 _limit = limit; 340 } 341 342 // All the strange bit-encodings are in here. 343 // The idea is to encode relocation data which are small integers 344 // very efficiently (a single extra halfword). Larger chunks of 345 // relocation data need a halfword header to hold their size. 346 void RelocIterator::advance_over_prefix() { 347 if (_current->is_datalen()) { 348 _data = (short*) _current->data(); 349 _datalen = _current->datalen(); 350 _current += _datalen + 1; // skip the embedded data & header 351 } else { 352 _databuf = _current->immediate(); 353 _data = &_databuf; 354 _datalen = 1; 355 _current++; // skip the header 356 } 357 // The client will see the following relocInfo, whatever that is. 358 // It is the reloc to which the preceding data applies. 359 } 360 361 362 void RelocIterator::initialize_misc() { 363 set_has_current(false); 364 for (int i = (int) CodeBuffer::SECT_FIRST; i < (int) CodeBuffer::SECT_LIMIT; i++) { 365 _section_start[i] = NULL; // these will be lazily computed, if needed 366 _section_end [i] = NULL; 367 } 368 } 369 370 371 Relocation* RelocIterator::reloc() { 372 // (take the "switch" out-of-line) 373 relocInfo::relocType t = type(); 374 if (false) {} 375 #define EACH_TYPE(name) \ 376 else if (t == relocInfo::name##_type) { \ 377 return name##_reloc(); \ 378 } 379 APPLY_TO_RELOCATIONS(EACH_TYPE); 380 #undef EACH_TYPE 381 assert(t == relocInfo::none, "must be padding"); 382 return new(_rh) Relocation(); 383 } 384 385 386 //////// Methods for flyweight Relocation types 387 388 389 RelocationHolder RelocationHolder::plus(int offset) const { 390 if (offset != 0) { 391 switch (type()) { 392 case relocInfo::none: 393 break; 394 case relocInfo::oop_type: 395 { 396 oop_Relocation* r = (oop_Relocation*)reloc(); 397 return oop_Relocation::spec(r->oop_index(), r->offset() + offset); 398 } 399 case relocInfo::metadata_type: 400 { 401 metadata_Relocation* r = (metadata_Relocation*)reloc(); 402 return metadata_Relocation::spec(r->metadata_index(), r->offset() + offset); 403 } 404 default: 405 ShouldNotReachHere(); 406 } 407 } 408 return (*this); 409 } 410 411 412 void Relocation::guarantee_size() { 413 guarantee(false, "Make _relocbuf bigger!"); 414 } 415 416 // some relocations can compute their own values 417 address Relocation::value() { 418 ShouldNotReachHere(); 419 return NULL; 420 } 421 422 423 void Relocation::set_value(address x) { 424 ShouldNotReachHere(); 425 } 426 427 428 RelocationHolder Relocation::spec_simple(relocInfo::relocType rtype) { 429 if (rtype == relocInfo::none) return RelocationHolder::none; 430 relocInfo ri = relocInfo(rtype, 0); 431 RelocIterator itr; 432 itr.set_current(ri); 433 itr.reloc(); 434 return itr._rh; 435 } 436 437 int32_t Relocation::runtime_address_to_index(address runtime_address) { 438 assert(!is_reloc_index((intptr_t)runtime_address), "must not look like an index"); 439 440 if (runtime_address == NULL) return 0; 441 442 StubCodeDesc* p = StubCodeDesc::desc_for(runtime_address); 443 if (p != NULL && p->begin() == runtime_address) { 444 assert(is_reloc_index(p->index()), "there must not be too many stubs"); 445 return (int32_t)p->index(); 446 } else { 447 // Known "miscellaneous" non-stub pointers: 448 // os::get_polling_page(), SafepointSynchronize::address_of_state() 449 if (PrintRelocations) { 450 tty->print_cr("random unregistered address in relocInfo: " INTPTR_FORMAT, runtime_address); 451 } 452 #ifndef _LP64 453 return (int32_t) (intptr_t)runtime_address; 454 #else 455 // didn't fit return non-index 456 return -1; 457 #endif /* _LP64 */ 458 } 459 } 460 461 462 address Relocation::index_to_runtime_address(int32_t index) { 463 if (index == 0) return NULL; 464 465 if (is_reloc_index(index)) { 466 StubCodeDesc* p = StubCodeDesc::desc_for_index(index); 467 assert(p != NULL, "there must be a stub for this index"); 468 return p->begin(); 469 } else { 470 #ifndef _LP64 471 // this only works on 32bit machines 472 return (address) ((intptr_t) index); 473 #else 474 fatal("Relocation::index_to_runtime_address, int32_t not pointer sized"); 475 return NULL; 476 #endif /* _LP64 */ 477 } 478 } 479 480 address Relocation::old_addr_for(address newa, 481 const CodeBuffer* src, CodeBuffer* dest) { 482 int sect = dest->section_index_of(newa); 483 guarantee(sect != CodeBuffer::SECT_NONE, "lost track of this address"); 484 address ostart = src->code_section(sect)->start(); 485 address nstart = dest->code_section(sect)->start(); 486 return ostart + (newa - nstart); 487 } 488 489 address Relocation::new_addr_for(address olda, 490 const CodeBuffer* src, CodeBuffer* dest) { 491 debug_only(const CodeBuffer* src0 = src); 492 int sect = CodeBuffer::SECT_NONE; 493 // Look for olda in the source buffer, and all previous incarnations 494 // if the source buffer has been expanded. 495 for (; src != NULL; src = src->before_expand()) { 496 sect = src->section_index_of(olda); 497 if (sect != CodeBuffer::SECT_NONE) break; 498 } 499 guarantee(sect != CodeBuffer::SECT_NONE, "lost track of this address"); 500 address ostart = src->code_section(sect)->start(); 501 address nstart = dest->code_section(sect)->start(); 502 return nstart + (olda - ostart); 503 } 504 505 void Relocation::normalize_address(address& addr, const CodeSection* dest, bool allow_other_sections) { 506 address addr0 = addr; 507 if (addr0 == NULL || dest->allocates2(addr0)) return; 508 CodeBuffer* cb = dest->outer(); 509 addr = new_addr_for(addr0, cb, cb); 510 assert(allow_other_sections || dest->contains2(addr), 511 "addr must be in required section"); 512 } 513 514 515 void CallRelocation::set_destination(address x) { 516 pd_set_call_destination(x); 517 } 518 519 void CallRelocation::fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest) { 520 // Usually a self-relative reference to an external routine. 521 // On some platforms, the reference is absolute (not self-relative). 522 // The enhanced use of pd_call_destination sorts this all out. 523 address orig_addr = old_addr_for(addr(), src, dest); 524 address callee = pd_call_destination(orig_addr); 525 // Reassert the callee address, this time in the new copy of the code. 526 pd_set_call_destination(callee); 527 } 528 529 530 //// pack/unpack methods 531 532 void oop_Relocation::pack_data_to(CodeSection* dest) { 533 short* p = (short*) dest->locs_end(); 534 p = pack_2_ints_to(p, _oop_index, _offset); 535 dest->set_locs_end((relocInfo*) p); 536 } 537 538 539 void oop_Relocation::unpack_data() { 540 unpack_2_ints(_oop_index, _offset); 541 } 542 543 void metadata_Relocation::pack_data_to(CodeSection* dest) { 544 short* p = (short*) dest->locs_end(); 545 p = pack_2_ints_to(p, _metadata_index, _offset); 546 dest->set_locs_end((relocInfo*) p); 547 } 548 549 550 void metadata_Relocation::unpack_data() { 551 unpack_2_ints(_metadata_index, _offset); 552 } 553 554 555 void virtual_call_Relocation::pack_data_to(CodeSection* dest) { 556 short* p = (short*) dest->locs_end(); 557 address point = dest->locs_point(); 558 559 normalize_address(_cached_value, dest); 560 jint x0 = scaled_offset_null_special(_cached_value, point); 561 p = pack_1_int_to(p, x0); 562 dest->set_locs_end((relocInfo*) p); 563 } 564 565 566 void virtual_call_Relocation::unpack_data() { 567 jint x0 = unpack_1_int(); 568 address point = addr(); 569 _cached_value = x0==0? NULL: address_from_scaled_offset(x0, point); 570 } 571 572 573 void static_stub_Relocation::pack_data_to(CodeSection* dest) { 574 short* p = (short*) dest->locs_end(); 575 CodeSection* insts = dest->outer()->insts(); 576 normalize_address(_static_call, insts); 577 p = pack_1_int_to(p, scaled_offset(_static_call, insts->start())); 578 dest->set_locs_end((relocInfo*) p); 579 } 580 581 void static_stub_Relocation::unpack_data() { 582 address base = binding()->section_start(CodeBuffer::SECT_INSTS); 583 _static_call = address_from_scaled_offset(unpack_1_int(), base); 584 } 585 586 void trampoline_stub_Relocation::pack_data_to(CodeSection* dest ) { 587 short* p = (short*) dest->locs_end(); 588 CodeSection* insts = dest->outer()->insts(); 589 normalize_address(_owner, insts); 590 p = pack_1_int_to(p, scaled_offset(_owner, insts->start())); 591 dest->set_locs_end((relocInfo*) p); 592 } 593 594 void trampoline_stub_Relocation::unpack_data() { 595 address base = binding()->section_start(CodeBuffer::SECT_INSTS); 596 _owner = address_from_scaled_offset(unpack_1_int(), base); 597 } 598 599 void external_word_Relocation::pack_data_to(CodeSection* dest) { 600 short* p = (short*) dest->locs_end(); 601 int32_t index = runtime_address_to_index(_target); 602 #ifndef _LP64 603 p = pack_1_int_to(p, index); 604 #else 605 if (is_reloc_index(index)) { 606 p = pack_2_ints_to(p, index, 0); 607 } else { 608 jlong t = (jlong) _target; 609 int32_t lo = low(t); 610 int32_t hi = high(t); 611 p = pack_2_ints_to(p, lo, hi); 612 DEBUG_ONLY(jlong t1 = jlong_from(hi, lo)); 613 assert(!is_reloc_index(t1) && (address) t1 == _target, "not symmetric"); 614 } 615 #endif /* _LP64 */ 616 dest->set_locs_end((relocInfo*) p); 617 } 618 619 620 void external_word_Relocation::unpack_data() { 621 #ifndef _LP64 622 _target = index_to_runtime_address(unpack_1_int()); 623 #else 624 int32_t lo, hi; 625 unpack_2_ints(lo, hi); 626 jlong t = jlong_from(hi, lo);; 627 if (is_reloc_index(t)) { 628 _target = index_to_runtime_address(t); 629 } else { 630 _target = (address) t; 631 } 632 #endif /* _LP64 */ 633 } 634 635 636 void internal_word_Relocation::pack_data_to(CodeSection* dest) { 637 short* p = (short*) dest->locs_end(); 638 normalize_address(_target, dest, true); 639 640 // Check whether my target address is valid within this section. 641 // If not, strengthen the relocation type to point to another section. 642 int sindex = _section; 643 if (sindex == CodeBuffer::SECT_NONE && _target != NULL 644 && (!dest->allocates(_target) || _target == dest->locs_point())) { 645 sindex = dest->outer()->section_index_of(_target); 646 guarantee(sindex != CodeBuffer::SECT_NONE, "must belong somewhere"); 647 relocInfo* base = dest->locs_end() - 1; 648 assert(base->type() == this->type(), "sanity"); 649 // Change the written type, to be section_word_type instead. 650 base->set_type(relocInfo::section_word_type); 651 } 652 653 // Note: An internal_word relocation cannot refer to its own instruction, 654 // because we reserve "0" to mean that the pointer itself is embedded 655 // in the code stream. We use a section_word relocation for such cases. 656 657 if (sindex == CodeBuffer::SECT_NONE) { 658 assert(type() == relocInfo::internal_word_type, "must be base class"); 659 guarantee(_target == NULL || dest->allocates2(_target), "must be within the given code section"); 660 jint x0 = scaled_offset_null_special(_target, dest->locs_point()); 661 assert(!(x0 == 0 && _target != NULL), "correct encoding of null target"); 662 p = pack_1_int_to(p, x0); 663 } else { 664 assert(_target != NULL, "sanity"); 665 CodeSection* sect = dest->outer()->code_section(sindex); 666 guarantee(sect->allocates2(_target), "must be in correct section"); 667 address base = sect->start(); 668 jint offset = scaled_offset(_target, base); 669 assert((uint)sindex < (uint)CodeBuffer::SECT_LIMIT, "sanity"); 670 assert(CodeBuffer::SECT_LIMIT <= (1 << section_width), "section_width++"); 671 p = pack_1_int_to(p, (offset << section_width) | sindex); 672 } 673 674 dest->set_locs_end((relocInfo*) p); 675 } 676 677 678 void internal_word_Relocation::unpack_data() { 679 jint x0 = unpack_1_int(); 680 _target = x0==0? NULL: address_from_scaled_offset(x0, addr()); 681 _section = CodeBuffer::SECT_NONE; 682 } 683 684 685 void section_word_Relocation::unpack_data() { 686 jint x = unpack_1_int(); 687 jint offset = (x >> section_width); 688 int sindex = (x & ((1<<section_width)-1)); 689 address base = binding()->section_start(sindex); 690 691 _section = sindex; 692 _target = address_from_scaled_offset(offset, base); 693 } 694 695 //// miscellaneous methods 696 oop* oop_Relocation::oop_addr() { 697 int n = _oop_index; 698 if (n == 0) { 699 // oop is stored in the code stream 700 return (oop*) pd_address_in_code(); 701 } else { 702 // oop is stored in table at nmethod::oops_begin 703 return code()->oop_addr_at(n); 704 } 705 } 706 707 708 oop oop_Relocation::oop_value() { 709 oop v = *oop_addr(); 710 // clean inline caches store a special pseudo-null 711 if (v == (oop)Universe::non_oop_word()) v = NULL; 712 return v; 713 } 714 715 716 void oop_Relocation::fix_oop_relocation() { 717 if (!oop_is_immediate()) { 718 // get the oop from the pool, and re-insert it into the instruction: 719 set_value(value()); 720 } 721 } 722 723 724 void oop_Relocation::verify_oop_relocation() { 725 if (!oop_is_immediate()) { 726 // get the oop from the pool, and re-insert it into the instruction: 727 verify_value(value()); 728 } 729 } 730 731 // meta data versions 732 Metadata** metadata_Relocation::metadata_addr() { 733 int n = _metadata_index; 734 if (n == 0) { 735 // metadata is stored in the code stream 736 return (Metadata**) pd_address_in_code(); 737 } else { 738 // metadata is stored in table at nmethod::metadatas_begin 739 return code()->metadata_addr_at(n); 740 } 741 } 742 743 744 Metadata* metadata_Relocation::metadata_value() { 745 Metadata* v = *metadata_addr(); 746 // clean inline caches store a special pseudo-null 747 if (v == (Metadata*)Universe::non_oop_word()) v = NULL; 748 return v; 749 } 750 751 752 void metadata_Relocation::fix_metadata_relocation() { 753 if (!metadata_is_immediate()) { 754 // get the metadata from the pool, and re-insert it into the instruction: 755 pd_fix_value(value()); 756 } 757 } 758 759 760 void metadata_Relocation::verify_metadata_relocation() { 761 if (!metadata_is_immediate()) { 762 // get the metadata from the pool, and re-insert it into the instruction: 763 verify_value(value()); 764 } 765 } 766 767 address virtual_call_Relocation::cached_value() { 768 assert(_cached_value != NULL && _cached_value < addr(), "must precede ic_call"); 769 return _cached_value; 770 } 771 772 773 void virtual_call_Relocation::clear_inline_cache() { 774 // No stubs for ICs 775 // Clean IC 776 ResourceMark rm; 777 CompiledIC* icache = CompiledIC_at(this); 778 icache->set_to_clean(); 779 } 780 781 782 void opt_virtual_call_Relocation::clear_inline_cache() { 783 // No stubs for ICs 784 // Clean IC 785 ResourceMark rm; 786 CompiledIC* icache = CompiledIC_at(this); 787 icache->set_to_clean(); 788 } 789 790 791 address opt_virtual_call_Relocation::static_stub() { 792 // search for the static stub who points back to this static call 793 address static_call_addr = addr(); 794 RelocIterator iter(code()); 795 while (iter.next()) { 796 if (iter.type() == relocInfo::static_stub_type) { 797 if (iter.static_stub_reloc()->static_call() == static_call_addr) { 798 return iter.addr(); 799 } 800 } 801 } 802 return NULL; 803 } 804 805 806 void static_call_Relocation::clear_inline_cache() { 807 // Safe call site info 808 CompiledStaticCall* handler = compiledStaticCall_at(this); 809 handler->set_to_clean(); 810 } 811 812 813 address static_call_Relocation::static_stub() { 814 // search for the static stub who points back to this static call 815 address static_call_addr = addr(); 816 RelocIterator iter(code()); 817 while (iter.next()) { 818 if (iter.type() == relocInfo::static_stub_type) { 819 if (iter.static_stub_reloc()->static_call() == static_call_addr) { 820 return iter.addr(); 821 } 822 } 823 } 824 return NULL; 825 } 826 827 // Finds the trampoline address for a call. If no trampoline stub is 828 // found NULL is returned which can be handled by the caller. 829 address trampoline_stub_Relocation::get_trampoline_for(address call, nmethod* code) { 830 // There are no relocations available when the code gets relocated 831 // because of CodeBuffer expansion. 832 if (code->relocation_size() == 0) 833 return NULL; 834 835 RelocIterator iter(code, call); 836 while (iter.next()) { 837 if (iter.type() == relocInfo::trampoline_stub_type) { 838 if (iter.trampoline_stub_reloc()->owner() == call) { 839 return iter.addr(); 840 } 841 } 842 } 843 844 return NULL; 845 } 846 847 void static_stub_Relocation::clear_inline_cache() { 848 // Call stub is only used when calling the interpreted code. 849 // It does not really need to be cleared, except that we want to clean out the methodoop. 850 CompiledStaticCall::set_stub_to_clean(this); 851 } 852 853 854 void external_word_Relocation::fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest) { 855 address target = _target; 856 if (target == NULL) { 857 // An absolute embedded reference to an external location, 858 // which means there is nothing to fix here. 859 return; 860 } 861 // Probably this reference is absolute, not relative, so the 862 // following is probably a no-op. 863 assert(src->section_index_of(target) == CodeBuffer::SECT_NONE, "sanity"); 864 set_value(target); 865 } 866 867 868 address external_word_Relocation::target() { 869 address target = _target; 870 if (target == NULL) { 871 target = pd_get_address_from_code(); 872 } 873 return target; 874 } 875 876 877 void internal_word_Relocation::fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest) { 878 address target = _target; 879 if (target == NULL) { 880 target = new_addr_for(this->target(), src, dest); 881 } 882 set_value(target); 883 } 884 885 886 address internal_word_Relocation::target() { 887 address target = _target; 888 if (target == NULL) { 889 if (addr_in_const()) { 890 target = *(address*)addr(); 891 } else { 892 target = pd_get_address_from_code(); 893 } 894 } 895 return target; 896 } 897 898 //--------------------------------------------------------------------------------- 899 // Non-product code 900 901 #ifndef PRODUCT 902 903 static const char* reloc_type_string(relocInfo::relocType t) { 904 switch (t) { 905 #define EACH_CASE(name) \ 906 case relocInfo::name##_type: \ 907 return #name; 908 909 APPLY_TO_RELOCATIONS(EACH_CASE); 910 #undef EACH_CASE 911 912 case relocInfo::none: 913 return "none"; 914 case relocInfo::data_prefix_tag: 915 return "prefix"; 916 default: 917 return "UNKNOWN RELOC TYPE"; 918 } 919 } 920 921 922 void RelocIterator::print_current() { 923 if (!has_current()) { 924 tty->print_cr("(no relocs)"); 925 return; 926 } 927 tty->print("relocInfo@" INTPTR_FORMAT " [type=%d(%s) addr=" INTPTR_FORMAT " offset=%d", 928 _current, type(), reloc_type_string((relocInfo::relocType) type()), _addr, _current->addr_offset()); 929 if (current()->format() != 0) 930 tty->print(" format=%d", current()->format()); 931 if (datalen() == 1) { 932 tty->print(" data=%d", data()[0]); 933 } else if (datalen() > 0) { 934 tty->print(" data={"); 935 for (int i = 0; i < datalen(); i++) { 936 tty->print("%04x", data()[i] & 0xFFFF); 937 } 938 tty->print("}"); 939 } 940 tty->print("]"); 941 switch (type()) { 942 case relocInfo::oop_type: 943 { 944 oop_Relocation* r = oop_reloc(); 945 oop* oop_addr = NULL; 946 oop raw_oop = NULL; 947 oop oop_value = NULL; 948 if (code() != NULL || r->oop_is_immediate()) { 949 oop_addr = r->oop_addr(); 950 raw_oop = *oop_addr; 951 oop_value = r->oop_value(); 952 } 953 tty->print(" | [oop_addr=" INTPTR_FORMAT " *=" INTPTR_FORMAT " offset=%d]", 954 oop_addr, (address)raw_oop, r->offset()); 955 // Do not print the oop by default--we want this routine to 956 // work even during GC or other inconvenient times. 957 if (WizardMode && oop_value != NULL) { 958 tty->print("oop_value=" INTPTR_FORMAT ": ", (address)oop_value); 959 oop_value->print_value_on(tty); 960 } 961 break; 962 } 963 case relocInfo::metadata_type: 964 { 965 metadata_Relocation* r = metadata_reloc(); 966 Metadata** metadata_addr = NULL; 967 Metadata* raw_metadata = NULL; 968 Metadata* metadata_value = NULL; 969 if (code() != NULL || r->metadata_is_immediate()) { 970 metadata_addr = r->metadata_addr(); 971 raw_metadata = *metadata_addr; 972 metadata_value = r->metadata_value(); 973 } 974 tty->print(" | [metadata_addr=" INTPTR_FORMAT " *=" INTPTR_FORMAT " offset=%d]", 975 metadata_addr, (address)raw_metadata, r->offset()); 976 if (metadata_value != NULL) { 977 tty->print("metadata_value=" INTPTR_FORMAT ": ", (address)metadata_value); 978 metadata_value->print_value_on(tty); 979 } 980 break; 981 } 982 case relocInfo::external_word_type: 983 case relocInfo::internal_word_type: 984 case relocInfo::section_word_type: 985 { 986 DataRelocation* r = (DataRelocation*) reloc(); 987 tty->print(" | [target=" INTPTR_FORMAT "]", r->value()); //value==target 988 break; 989 } 990 case relocInfo::static_call_type: 991 case relocInfo::runtime_call_type: 992 { 993 CallRelocation* r = (CallRelocation*) reloc(); 994 tty->print(" | [destination=" INTPTR_FORMAT "]", r->destination()); 995 break; 996 } 997 case relocInfo::virtual_call_type: 998 { 999 virtual_call_Relocation* r = (virtual_call_Relocation*) reloc(); 1000 tty->print(" | [destination=" INTPTR_FORMAT " cached_value=" INTPTR_FORMAT "]", 1001 r->destination(), r->cached_value()); 1002 break; 1003 } 1004 case relocInfo::static_stub_type: 1005 { 1006 static_stub_Relocation* r = (static_stub_Relocation*) reloc(); 1007 tty->print(" | [static_call=" INTPTR_FORMAT "]", r->static_call()); 1008 break; 1009 } 1010 case relocInfo::trampoline_stub_type: 1011 { 1012 trampoline_stub_Relocation* r = (trampoline_stub_Relocation*) reloc(); 1013 tty->print(" | [trampoline owner=" INTPTR_FORMAT "]", r->owner()); 1014 break; 1015 } 1016 } 1017 tty->cr(); 1018 } 1019 1020 1021 void RelocIterator::print() { 1022 RelocIterator save_this = (*this); 1023 relocInfo* scan = _current; 1024 if (!has_current()) scan += 1; // nothing to scan here! 1025 1026 bool skip_next = has_current(); 1027 bool got_next; 1028 while (true) { 1029 got_next = (skip_next || next()); 1030 skip_next = false; 1031 1032 tty->print(" @" INTPTR_FORMAT ": ", scan); 1033 relocInfo* newscan = _current+1; 1034 if (!has_current()) newscan -= 1; // nothing to scan here! 1035 while (scan < newscan) { 1036 tty->print("%04x", *(short*)scan & 0xFFFF); 1037 scan++; 1038 } 1039 tty->cr(); 1040 1041 if (!got_next) break; 1042 print_current(); 1043 } 1044 1045 (*this) = save_this; 1046 } 1047 1048 // For the debugger: 1049 extern "C" 1050 void print_blob_locs(nmethod* nm) { 1051 nm->print(); 1052 RelocIterator iter(nm); 1053 iter.print(); 1054 } 1055 extern "C" 1056 void print_buf_locs(CodeBuffer* cb) { 1057 FlagSetting fs(PrintRelocations, true); 1058 cb->print(); 1059 } 1060 #endif // !PRODUCT