codeBuffer.cpp revision 196:d1605aabd0a1
1301169Slidl/* 2301169Slidl * Copyright 1997-2008 Sun Microsystems, Inc. All Rights Reserved. 3301169Slidl * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4301169Slidl * 5301169Slidl * This code is free software; you can redistribute it and/or modify it 6301169Slidl * under the terms of the GNU General Public License version 2 only, as 7301169Slidl * published by the Free Software Foundation. 8301169Slidl * 9301169Slidl * This code is distributed in the hope that it will be useful, but WITHOUT 10301169Slidl * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11301169Slidl * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12301169Slidl * version 2 for more details (a copy is included in the LICENSE file that 13301169Slidl * accompanied this code). 14301169Slidl * 15301169Slidl * You should have received a copy of the GNU General Public License version 16301169Slidl * 2 along with this work; if not, write to the Free Software Foundation, 17301169Slidl * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18301169Slidl * 19301169Slidl * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, 20301169Slidl * CA 95054 USA or visit www.sun.com if you need additional information or 21301169Slidl * have any questions. 22301169Slidl * 23301169Slidl */ 24301169Slidl 25301169Slidl# include "incls/_precompiled.incl" 26301169Slidl# include "incls/_codeBuffer.cpp.incl" 27301169Slidl 28301169Slidl// The structure of a CodeSection: 29301169Slidl// 30301169Slidl// _start -> +----------------+ 31301169Slidl// | machine code...| 32301169Slidl// _end -> |----------------| 33301169Slidl// | | 34301169Slidl// | (empty) | 35301169Slidl// | | 36301169Slidl// | | 37301169Slidl// +----------------+ 38301169Slidl// _limit -> | | 39301169Slidl// 40301169Slidl// _locs_start -> +----------------+ 41301169Slidl// |reloc records...| 42301169Slidl// |----------------| 43301169Slidl// _locs_end -> | | 44301169Slidl// | | 45301169Slidl// | (empty) | 46301169Slidl// | | 47301169Slidl// | | 48301169Slidl// +----------------+ 49301169Slidl// _locs_limit -> | | 50301169Slidl// The _end (resp. _limit) pointer refers to the first 51301169Slidl// unused (resp. unallocated) byte. 52301169Slidl 53301169Slidl// The structure of the CodeBuffer while code is being accumulated: 54301169Slidl// 55301169Slidl// _total_start -> \ 56301169Slidl// _insts._start -> +----------------+ 57301169Slidl// | | 58301169Slidl// | Code | 59301169Slidl// | | 60301169Slidl// _stubs._start -> |----------------| 61301169Slidl// | | 62301169Slidl// | Stubs | (also handlers for deopt/exception) 63301169Slidl// | | 64301169Slidl// _consts._start -> |----------------| 65301169Slidl// | | 66301169Slidl// | Constants | 67301169Slidl// | | 68301169Slidl// +----------------+ 69301169Slidl// + _total_size -> | | 70301169Slidl// 71301169Slidl// When the code and relocations are copied to the code cache, 72301169Slidl// the empty parts of each section are removed, and everything 73301169Slidl// is copied into contiguous locations. 74301169Slidl 75301169Slidltypedef CodeBuffer::csize_t csize_t; // file-local definition 76301169Slidl 77301169Slidl// external buffer, in a predefined CodeBlob or other buffer area 78301169Slidl// Important: The code_start must be taken exactly, and not realigned. 79301169SlidlCodeBuffer::CodeBuffer(address code_start, csize_t code_size) { 80301169Slidl assert(code_start != NULL, "sanity"); 81301169Slidl initialize_misc("static buffer"); 82301169Slidl initialize(code_start, code_size); 83301169Slidl assert(verify_section_allocation(), "initial use of buffer OK"); 84301169Slidl} 85301169Slidl 86301169Slidlvoid CodeBuffer::initialize(csize_t code_size, csize_t locs_size) { 87301169Slidl // Compute maximal alignment. 88301169Slidl int align = _insts.alignment(); 89301169Slidl // Always allow for empty slop around each section. 90301169Slidl int slop = (int) CodeSection::end_slop(); 91301169Slidl 92301169Slidl assert(blob() == NULL, "only once"); 93301169Slidl set_blob(BufferBlob::create(_name, code_size + (align+slop) * (SECT_LIMIT+1))); 94301169Slidl if (blob() == NULL) { 95301169Slidl // The assembler constructor will throw a fatal on an empty CodeBuffer. 96301169Slidl return; // caller must test this 97301169Slidl } 98301169Slidl 99301169Slidl // Set up various pointers into the blob. 100301169Slidl initialize(_total_start, _total_size); 101301169Slidl 102301169Slidl assert((uintptr_t)code_begin() % CodeEntryAlignment == 0, "instruction start not code entry aligned"); 103301169Slidl 104301169Slidl pd_initialize(); 105301169Slidl 106301169Slidl if (locs_size != 0) { 107301169Slidl _insts.initialize_locs(locs_size / sizeof(relocInfo)); 108301169Slidl } 109301169Slidl 110301169Slidl assert(verify_section_allocation(), "initial use of blob is OK"); 111301169Slidl} 112301169Slidl 113301169Slidl 114301169SlidlCodeBuffer::~CodeBuffer() { 115301169Slidl // If we allocate our code buffer from the CodeCache 116301169Slidl // via a BufferBlob, and it's not permanent, then 117301169Slidl // free the BufferBlob. 118301169Slidl // The rest of the memory will be freed when the ResourceObj 119301169Slidl // is released. 120301169Slidl assert(verify_section_allocation(), "final storage configuration still OK"); 121301169Slidl for (CodeBuffer* cb = this; cb != NULL; cb = cb->before_expand()) { 122301169Slidl // Previous incarnations of this buffer are held live, so that internal 123301169Slidl // addresses constructed before expansions will not be confused. 124301169Slidl cb->free_blob(); 125301169Slidl } 126301169Slidl#ifdef ASSERT 127301169Slidl Copy::fill_to_bytes(this, sizeof(*this), badResourceValue); 128301169Slidl#endif 129301169Slidl} 130301169Slidl 131301169Slidlvoid CodeBuffer::initialize_oop_recorder(OopRecorder* r) { 132301169Slidl assert(_oop_recorder == &_default_oop_recorder && _default_oop_recorder.is_unused(), "do this once"); 133301169Slidl DEBUG_ONLY(_default_oop_recorder.oop_size()); // force unused OR to be frozen 134301169Slidl _oop_recorder = r; 135301169Slidl} 136301169Slidl 137301169Slidlvoid CodeBuffer::initialize_section_size(CodeSection* cs, csize_t size) { 138301169Slidl assert(cs != &_insts, "insts is the memory provider, not the consumer"); 139301169Slidl#ifdef ASSERT 140301169Slidl for (int n = (int)SECT_INSTS+1; n < (int)SECT_LIMIT; n++) { 141301169Slidl CodeSection* prevCS = code_section(n); 142301169Slidl if (prevCS == cs) break; 143301169Slidl assert(!prevCS->is_allocated(), "section allocation must be in reverse order"); 144301169Slidl } 145301169Slidl#endif 146301169Slidl csize_t slop = CodeSection::end_slop(); // margin between sections 147301169Slidl int align = cs->alignment(); 148301169Slidl assert(is_power_of_2(align), "sanity"); 149301169Slidl address start = _insts._start; 150301169Slidl address limit = _insts._limit; 151301169Slidl address middle = limit - size; 152301169Slidl middle -= (intptr_t)middle & (align-1); // align the division point downward 153301169Slidl guarantee(middle - slop > start, "need enough space to divide up"); 154301169Slidl _insts._limit = middle - slop; // subtract desired space, plus slop 155301169Slidl cs->initialize(middle, limit - middle); 156301169Slidl assert(cs->start() == middle, "sanity"); 157301169Slidl assert(cs->limit() == limit, "sanity"); 158 // give it some relocations to start with, if the main section has them 159 if (_insts.has_locs()) cs->initialize_locs(1); 160} 161 162void CodeBuffer::freeze_section(CodeSection* cs) { 163 CodeSection* next_cs = (cs == consts())? NULL: code_section(cs->index()+1); 164 csize_t frozen_size = cs->size(); 165 if (next_cs != NULL) { 166 frozen_size = next_cs->align_at_start(frozen_size); 167 } 168 address old_limit = cs->limit(); 169 address new_limit = cs->start() + frozen_size; 170 relocInfo* old_locs_limit = cs->locs_limit(); 171 relocInfo* new_locs_limit = cs->locs_end(); 172 // Patch the limits. 173 cs->_limit = new_limit; 174 cs->_locs_limit = new_locs_limit; 175 cs->_frozen = true; 176 if (!next_cs->is_allocated() && !next_cs->is_frozen()) { 177 // Give remaining buffer space to the following section. 178 next_cs->initialize(new_limit, old_limit - new_limit); 179 next_cs->initialize_shared_locs(new_locs_limit, 180 old_locs_limit - new_locs_limit); 181 } 182} 183 184void CodeBuffer::set_blob(BufferBlob* blob) { 185 _blob = blob; 186 if (blob != NULL) { 187 address start = blob->instructions_begin(); 188 address end = blob->instructions_end(); 189 // Round up the starting address. 190 int align = _insts.alignment(); 191 start += (-(intptr_t)start) & (align-1); 192 _total_start = start; 193 _total_size = end - start; 194 } else { 195 #ifdef ASSERT 196 // Clean out dangling pointers. 197 _total_start = badAddress; 198 _insts._start = _insts._end = badAddress; 199 _stubs._start = _stubs._end = badAddress; 200 _consts._start = _consts._end = badAddress; 201 #endif //ASSERT 202 } 203} 204 205void CodeBuffer::free_blob() { 206 if (_blob != NULL) { 207 BufferBlob::free(_blob); 208 set_blob(NULL); 209 } 210} 211 212const char* CodeBuffer::code_section_name(int n) { 213#ifdef PRODUCT 214 return NULL; 215#else //PRODUCT 216 switch (n) { 217 case SECT_INSTS: return "insts"; 218 case SECT_STUBS: return "stubs"; 219 case SECT_CONSTS: return "consts"; 220 default: return NULL; 221 } 222#endif //PRODUCT 223} 224 225int CodeBuffer::section_index_of(address addr) const { 226 for (int n = 0; n < (int)SECT_LIMIT; n++) { 227 const CodeSection* cs = code_section(n); 228 if (cs->allocates(addr)) return n; 229 } 230 return SECT_NONE; 231} 232 233int CodeBuffer::locator(address addr) const { 234 for (int n = 0; n < (int)SECT_LIMIT; n++) { 235 const CodeSection* cs = code_section(n); 236 if (cs->allocates(addr)) { 237 return locator(addr - cs->start(), n); 238 } 239 } 240 return -1; 241} 242 243address CodeBuffer::locator_address(int locator) const { 244 if (locator < 0) return NULL; 245 address start = code_section(locator_sect(locator))->start(); 246 return start + locator_pos(locator); 247} 248 249address CodeBuffer::decode_begin() { 250 address begin = _insts.start(); 251 if (_decode_begin != NULL && _decode_begin > begin) 252 begin = _decode_begin; 253 return begin; 254} 255 256 257GrowableArray<int>* CodeBuffer::create_patch_overflow() { 258 if (_overflow_arena == NULL) { 259 _overflow_arena = new Arena(); 260 } 261 return new (_overflow_arena) GrowableArray<int>(_overflow_arena, 8, 0, 0); 262} 263 264 265// Helper function for managing labels and their target addresses. 266// Returns a sensible address, and if it is not the label's final 267// address, notes the dependency (at 'branch_pc') on the label. 268address CodeSection::target(Label& L, address branch_pc) { 269 if (L.is_bound()) { 270 int loc = L.loc(); 271 if (index() == CodeBuffer::locator_sect(loc)) { 272 return start() + CodeBuffer::locator_pos(loc); 273 } else { 274 return outer()->locator_address(loc); 275 } 276 } else { 277 assert(allocates2(branch_pc), "sanity"); 278 address base = start(); 279 int patch_loc = CodeBuffer::locator(branch_pc - base, index()); 280 L.add_patch_at(outer(), patch_loc); 281 282 // Need to return a pc, doesn't matter what it is since it will be 283 // replaced during resolution later. 284 // Don't return NULL or badAddress, since branches shouldn't overflow. 285 // Don't return base either because that could overflow displacements 286 // for shorter branches. It will get checked when bound. 287 return branch_pc; 288 } 289} 290 291void CodeSection::relocate(address at, RelocationHolder const& spec, int format) { 292 Relocation* reloc = spec.reloc(); 293 relocInfo::relocType rtype = (relocInfo::relocType) reloc->type(); 294 if (rtype == relocInfo::none) return; 295 296 // The assertion below has been adjusted, to also work for 297 // relocation for fixup. Sometimes we want to put relocation 298 // information for the next instruction, since it will be patched 299 // with a call. 300 assert(start() <= at && at <= end()+1, 301 "cannot relocate data outside code boundaries"); 302 303 if (!has_locs()) { 304 // no space for relocation information provided => code cannot be 305 // relocated. Make sure that relocate is only called with rtypes 306 // that can be ignored for this kind of code. 307 assert(rtype == relocInfo::none || 308 rtype == relocInfo::runtime_call_type || 309 rtype == relocInfo::internal_word_type|| 310 rtype == relocInfo::section_word_type || 311 rtype == relocInfo::external_word_type, 312 "code needs relocation information"); 313 // leave behind an indication that we attempted a relocation 314 DEBUG_ONLY(_locs_start = _locs_limit = (relocInfo*)badAddress); 315 return; 316 } 317 318 // Advance the point, noting the offset we'll have to record. 319 csize_t offset = at - locs_point(); 320 set_locs_point(at); 321 322 // Test for a couple of overflow conditions; maybe expand the buffer. 323 relocInfo* end = locs_end(); 324 relocInfo* req = end + relocInfo::length_limit; 325 // Check for (potential) overflow 326 if (req >= locs_limit() || offset >= relocInfo::offset_limit()) { 327 req += (uint)offset / (uint)relocInfo::offset_limit(); 328 if (req >= locs_limit()) { 329 // Allocate or reallocate. 330 expand_locs(locs_count() + (req - end)); 331 // reload pointer 332 end = locs_end(); 333 } 334 } 335 336 // If the offset is giant, emit filler relocs, of type 'none', but 337 // each carrying the largest possible offset, to advance the locs_point. 338 while (offset >= relocInfo::offset_limit()) { 339 assert(end < locs_limit(), "adjust previous paragraph of code"); 340 *end++ = filler_relocInfo(); 341 offset -= filler_relocInfo().addr_offset(); 342 } 343 344 // If it's a simple reloc with no data, we'll just write (rtype | offset). 345 (*end) = relocInfo(rtype, offset, format); 346 347 // If it has data, insert the prefix, as (data_prefix_tag | data1), data2. 348 end->initialize(this, reloc); 349} 350 351void CodeSection::initialize_locs(int locs_capacity) { 352 assert(_locs_start == NULL, "only one locs init step, please"); 353 // Apply a priori lower limits to relocation size: 354 csize_t min_locs = MAX2(size() / 16, (csize_t)4); 355 if (locs_capacity < min_locs) locs_capacity = min_locs; 356 relocInfo* locs_start = NEW_RESOURCE_ARRAY(relocInfo, locs_capacity); 357 _locs_start = locs_start; 358 _locs_end = locs_start; 359 _locs_limit = locs_start + locs_capacity; 360 _locs_own = true; 361} 362 363void CodeSection::initialize_shared_locs(relocInfo* buf, int length) { 364 assert(_locs_start == NULL, "do this before locs are allocated"); 365 // Internal invariant: locs buf must be fully aligned. 366 // See copy_relocations_to() below. 367 while ((uintptr_t)buf % HeapWordSize != 0 && length > 0) { 368 ++buf; --length; 369 } 370 if (length > 0) { 371 _locs_start = buf; 372 _locs_end = buf; 373 _locs_limit = buf + length; 374 _locs_own = false; 375 } 376} 377 378void CodeSection::initialize_locs_from(const CodeSection* source_cs) { 379 int lcount = source_cs->locs_count(); 380 if (lcount != 0) { 381 initialize_shared_locs(source_cs->locs_start(), lcount); 382 _locs_end = _locs_limit = _locs_start + lcount; 383 assert(is_allocated(), "must have copied code already"); 384 set_locs_point(start() + source_cs->locs_point_off()); 385 } 386 assert(this->locs_count() == source_cs->locs_count(), "sanity"); 387} 388 389void CodeSection::expand_locs(int new_capacity) { 390 if (_locs_start == NULL) { 391 initialize_locs(new_capacity); 392 return; 393 } else { 394 int old_count = locs_count(); 395 int old_capacity = locs_capacity(); 396 if (new_capacity < old_capacity * 2) 397 new_capacity = old_capacity * 2; 398 relocInfo* locs_start; 399 if (_locs_own) { 400 locs_start = REALLOC_RESOURCE_ARRAY(relocInfo, _locs_start, old_capacity, new_capacity); 401 } else { 402 locs_start = NEW_RESOURCE_ARRAY(relocInfo, new_capacity); 403 Copy::conjoint_bytes(_locs_start, locs_start, old_capacity * sizeof(relocInfo)); 404 _locs_own = true; 405 } 406 _locs_start = locs_start; 407 _locs_end = locs_start + old_count; 408 _locs_limit = locs_start + new_capacity; 409 } 410} 411 412 413/// Support for emitting the code to its final location. 414/// The pattern is the same for all functions. 415/// We iterate over all the sections, padding each to alignment. 416 417csize_t CodeBuffer::total_code_size() const { 418 csize_t code_size_so_far = 0; 419 for (int n = 0; n < (int)SECT_LIMIT; n++) { 420 const CodeSection* cs = code_section(n); 421 if (cs->is_empty()) continue; // skip trivial section 422 code_size_so_far = cs->align_at_start(code_size_so_far); 423 code_size_so_far += cs->size(); 424 } 425 return code_size_so_far; 426} 427 428void CodeBuffer::compute_final_layout(CodeBuffer* dest) const { 429 address buf = dest->_total_start; 430 csize_t buf_offset = 0; 431 assert(dest->_total_size >= total_code_size(), "must be big enough"); 432 433 { 434 // not sure why this is here, but why not... 435 int alignSize = MAX2((intx) sizeof(jdouble), CodeEntryAlignment); 436 assert( (dest->_total_start - _insts.start()) % alignSize == 0, "copy must preserve alignment"); 437 } 438 439 const CodeSection* prev_cs = NULL; 440 CodeSection* prev_dest_cs = NULL; 441 for (int n = 0; n < (int)SECT_LIMIT; n++) { 442 // figure compact layout of each section 443 const CodeSection* cs = code_section(n); 444 address cstart = cs->start(); 445 address cend = cs->end(); 446 csize_t csize = cend - cstart; 447 448 CodeSection* dest_cs = dest->code_section(n); 449 if (!cs->is_empty()) { 450 // Compute initial padding; assign it to the previous non-empty guy. 451 // Cf. figure_expanded_capacities. 452 csize_t padding = cs->align_at_start(buf_offset) - buf_offset; 453 if (padding != 0) { 454 buf_offset += padding; 455 assert(prev_dest_cs != NULL, "sanity"); 456 prev_dest_cs->_limit += padding; 457 } 458 #ifdef ASSERT 459 if (prev_cs != NULL && prev_cs->is_frozen() && n < SECT_CONSTS) { 460 // Make sure the ends still match up. 461 // This is important because a branch in a frozen section 462 // might target code in a following section, via a Label, 463 // and without a relocation record. See Label::patch_instructions. 464 address dest_start = buf+buf_offset; 465 csize_t start2start = cs->start() - prev_cs->start(); 466 csize_t dest_start2start = dest_start - prev_dest_cs->start(); 467 assert(start2start == dest_start2start, "cannot stretch frozen sect"); 468 } 469 #endif //ASSERT 470 prev_dest_cs = dest_cs; 471 prev_cs = cs; 472 } 473 474 debug_only(dest_cs->_start = NULL); // defeat double-initialization assert 475 dest_cs->initialize(buf+buf_offset, csize); 476 dest_cs->set_end(buf+buf_offset+csize); 477 assert(dest_cs->is_allocated(), "must always be allocated"); 478 assert(cs->is_empty() == dest_cs->is_empty(), "sanity"); 479 480 buf_offset += csize; 481 } 482 483 // Done calculating sections; did it come out to the right end? 484 assert(buf_offset == total_code_size(), "sanity"); 485 assert(dest->verify_section_allocation(), "final configuration works"); 486} 487 488csize_t CodeBuffer::total_offset_of(address addr) const { 489 csize_t code_size_so_far = 0; 490 for (int n = 0; n < (int)SECT_LIMIT; n++) { 491 const CodeSection* cs = code_section(n); 492 if (!cs->is_empty()) { 493 code_size_so_far = cs->align_at_start(code_size_so_far); 494 } 495 if (cs->contains2(addr)) { 496 return code_size_so_far + (addr - cs->start()); 497 } 498 code_size_so_far += cs->size(); 499 } 500#ifndef PRODUCT 501 tty->print_cr("Dangling address " PTR_FORMAT " in:", addr); 502 ((CodeBuffer*)this)->print(); 503#endif 504 ShouldNotReachHere(); 505 return -1; 506} 507 508csize_t CodeBuffer::total_relocation_size() const { 509 csize_t lsize = copy_relocations_to(NULL); // dry run only 510 csize_t csize = total_code_size(); 511 csize_t total = RelocIterator::locs_and_index_size(csize, lsize); 512 return (csize_t) align_size_up(total, HeapWordSize); 513} 514 515csize_t CodeBuffer::copy_relocations_to(CodeBlob* dest) const { 516 address buf = NULL; 517 csize_t buf_offset = 0; 518 csize_t buf_limit = 0; 519 if (dest != NULL) { 520 buf = (address)dest->relocation_begin(); 521 buf_limit = (address)dest->relocation_end() - buf; 522 assert((uintptr_t)buf % HeapWordSize == 0, "buf must be fully aligned"); 523 assert(buf_limit % HeapWordSize == 0, "buf must be evenly sized"); 524 } 525 // if dest == NULL, this is just the sizing pass 526 527 csize_t code_end_so_far = 0; 528 csize_t code_point_so_far = 0; 529 for (int n = 0; n < (int)SECT_LIMIT; n++) { 530 // pull relocs out of each section 531 const CodeSection* cs = code_section(n); 532 assert(!(cs->is_empty() && cs->locs_count() > 0), "sanity"); 533 if (cs->is_empty()) continue; // skip trivial section 534 relocInfo* lstart = cs->locs_start(); 535 relocInfo* lend = cs->locs_end(); 536 csize_t lsize = (csize_t)( (address)lend - (address)lstart ); 537 csize_t csize = cs->size(); 538 code_end_so_far = cs->align_at_start(code_end_so_far); 539 540 if (lsize > 0) { 541 // Figure out how to advance the combined relocation point 542 // first to the beginning of this section. 543 // We'll insert one or more filler relocs to span that gap. 544 // (Don't bother to improve this by editing the first reloc's offset.) 545 csize_t new_code_point = code_end_so_far; 546 for (csize_t jump; 547 code_point_so_far < new_code_point; 548 code_point_so_far += jump) { 549 jump = new_code_point - code_point_so_far; 550 relocInfo filler = filler_relocInfo(); 551 if (jump >= filler.addr_offset()) { 552 jump = filler.addr_offset(); 553 } else { // else shrink the filler to fit 554 filler = relocInfo(relocInfo::none, jump); 555 } 556 if (buf != NULL) { 557 assert(buf_offset + (csize_t)sizeof(filler) <= buf_limit, "filler in bounds"); 558 *(relocInfo*)(buf+buf_offset) = filler; 559 } 560 buf_offset += sizeof(filler); 561 } 562 563 // Update code point and end to skip past this section: 564 csize_t last_code_point = code_end_so_far + cs->locs_point_off(); 565 assert(code_point_so_far <= last_code_point, "sanity"); 566 code_point_so_far = last_code_point; // advance past this guy's relocs 567 } 568 code_end_so_far += csize; // advance past this guy's instructions too 569 570 // Done with filler; emit the real relocations: 571 if (buf != NULL && lsize != 0) { 572 assert(buf_offset + lsize <= buf_limit, "target in bounds"); 573 assert((uintptr_t)lstart % HeapWordSize == 0, "sane start"); 574 if (buf_offset % HeapWordSize == 0) { 575 // Use wordwise copies if possible: 576 Copy::disjoint_words((HeapWord*)lstart, 577 (HeapWord*)(buf+buf_offset), 578 (lsize + HeapWordSize-1) / HeapWordSize); 579 } else { 580 Copy::conjoint_bytes(lstart, buf+buf_offset, lsize); 581 } 582 } 583 buf_offset += lsize; 584 } 585 586 // Align end of relocation info in target. 587 while (buf_offset % HeapWordSize != 0) { 588 if (buf != NULL) { 589 relocInfo padding = relocInfo(relocInfo::none, 0); 590 assert(buf_offset + (csize_t)sizeof(padding) <= buf_limit, "padding in bounds"); 591 *(relocInfo*)(buf+buf_offset) = padding; 592 } 593 buf_offset += sizeof(relocInfo); 594 } 595 596 assert(code_end_so_far == total_code_size(), "sanity"); 597 598 // Account for index: 599 if (buf != NULL) { 600 RelocIterator::create_index(dest->relocation_begin(), 601 buf_offset / sizeof(relocInfo), 602 dest->relocation_end()); 603 } 604 605 return buf_offset; 606} 607 608void CodeBuffer::copy_code_to(CodeBlob* dest_blob) { 609#ifndef PRODUCT 610 if (PrintNMethods && (WizardMode || Verbose)) { 611 tty->print("done with CodeBuffer:"); 612 ((CodeBuffer*)this)->print(); 613 } 614#endif //PRODUCT 615 616 CodeBuffer dest(dest_blob->instructions_begin(), 617 dest_blob->instructions_size()); 618 assert(dest_blob->instructions_size() >= total_code_size(), "good sizing"); 619 this->compute_final_layout(&dest); 620 relocate_code_to(&dest); 621 622 // transfer comments from buffer to blob 623 dest_blob->set_comments(_comments); 624 625 // Done moving code bytes; were they the right size? 626 assert(round_to(dest.total_code_size(), oopSize) == dest_blob->instructions_size(), "sanity"); 627 628 // Flush generated code 629 ICache::invalidate_range(dest_blob->instructions_begin(), 630 dest_blob->instructions_size()); 631} 632 633// Move all my code into another code buffer. 634// Consult applicable relocs to repair embedded addresses. 635void CodeBuffer::relocate_code_to(CodeBuffer* dest) const { 636 DEBUG_ONLY(address dest_end = dest->_total_start + dest->_total_size); 637 for (int n = 0; n < (int)SECT_LIMIT; n++) { 638 // pull code out of each section 639 const CodeSection* cs = code_section(n); 640 if (cs->is_empty()) continue; // skip trivial section 641 CodeSection* dest_cs = dest->code_section(n); 642 assert(cs->size() == dest_cs->size(), "sanity"); 643 csize_t usize = dest_cs->size(); 644 csize_t wsize = align_size_up(usize, HeapWordSize); 645 assert(dest_cs->start() + wsize <= dest_end, "no overflow"); 646 // Copy the code as aligned machine words. 647 // This may also include an uninitialized partial word at the end. 648 Copy::disjoint_words((HeapWord*)cs->start(), 649 (HeapWord*)dest_cs->start(), 650 wsize / HeapWordSize); 651 652 if (dest->blob() == NULL) { 653 // Destination is a final resting place, not just another buffer. 654 // Normalize uninitialized bytes in the final padding. 655 Copy::fill_to_bytes(dest_cs->end(), dest_cs->remaining(), 656 Assembler::code_fill_byte()); 657 } 658 659 assert(cs->locs_start() != (relocInfo*)badAddress, 660 "this section carries no reloc storage, but reloc was attempted"); 661 662 // Make the new code copy use the old copy's relocations: 663 dest_cs->initialize_locs_from(cs); 664 665 { // Repair the pc relative information in the code after the move 666 RelocIterator iter(dest_cs); 667 while (iter.next()) { 668 iter.reloc()->fix_relocation_after_move(this, dest); 669 } 670 } 671 } 672} 673 674csize_t CodeBuffer::figure_expanded_capacities(CodeSection* which_cs, 675 csize_t amount, 676 csize_t* new_capacity) { 677 csize_t new_total_cap = 0; 678 679 int prev_n = -1; 680 for (int n = 0; n < (int)SECT_LIMIT; n++) { 681 const CodeSection* sect = code_section(n); 682 683 if (!sect->is_empty()) { 684 // Compute initial padding; assign it to the previous non-empty guy. 685 // Cf. compute_final_layout. 686 csize_t padding = sect->align_at_start(new_total_cap) - new_total_cap; 687 if (padding != 0) { 688 new_total_cap += padding; 689 assert(prev_n >= 0, "sanity"); 690 new_capacity[prev_n] += padding; 691 } 692 prev_n = n; 693 } 694 695 csize_t exp = sect->size(); // 100% increase 696 if ((uint)exp < 4*K) exp = 4*K; // minimum initial increase 697 if (sect == which_cs) { 698 if (exp < amount) exp = amount; 699 if (StressCodeBuffers) exp = amount; // expand only slightly 700 } else if (n == SECT_INSTS) { 701 // scale down inst increases to a more modest 25% 702 exp = 4*K + ((exp - 4*K) >> 2); 703 if (StressCodeBuffers) exp = amount / 2; // expand only slightly 704 } else if (sect->is_empty()) { 705 // do not grow an empty secondary section 706 exp = 0; 707 } 708 // Allow for inter-section slop: 709 exp += CodeSection::end_slop(); 710 csize_t new_cap = sect->size() + exp; 711 if (new_cap < sect->capacity()) { 712 // No need to expand after all. 713 new_cap = sect->capacity(); 714 } 715 new_capacity[n] = new_cap; 716 new_total_cap += new_cap; 717 } 718 719 return new_total_cap; 720} 721 722void CodeBuffer::expand(CodeSection* which_cs, csize_t amount) { 723#ifndef PRODUCT 724 if (PrintNMethods && (WizardMode || Verbose)) { 725 tty->print("expanding CodeBuffer:"); 726 this->print(); 727 } 728 729 if (StressCodeBuffers && blob() != NULL) { 730 static int expand_count = 0; 731 if (expand_count >= 0) expand_count += 1; 732 if (expand_count > 100 && is_power_of_2(expand_count)) { 733 tty->print_cr("StressCodeBuffers: have expanded %d times", expand_count); 734 // simulate an occasional allocation failure: 735 free_blob(); 736 } 737 } 738#endif //PRODUCT 739 740 // Resizing must be allowed 741 { 742 if (blob() == NULL) return; // caller must check for blob == NULL 743 for (int n = 0; n < (int)SECT_LIMIT; n++) { 744 guarantee(!code_section(n)->is_frozen(), "resizing not allowed when frozen"); 745 } 746 } 747 748 // Figure new capacity for each section. 749 csize_t new_capacity[SECT_LIMIT]; 750 csize_t new_total_cap 751 = figure_expanded_capacities(which_cs, amount, new_capacity); 752 753 // Create a new (temporary) code buffer to hold all the new data 754 CodeBuffer cb(name(), new_total_cap, 0); 755 if (cb.blob() == NULL) { 756 // Failed to allocate in code cache. 757 free_blob(); 758 return; 759 } 760 761 // Create an old code buffer to remember which addresses used to go where. 762 // This will be useful when we do final assembly into the code cache, 763 // because we will need to know how to warp any internal address that 764 // has been created at any time in this CodeBuffer's past. 765 CodeBuffer* bxp = new CodeBuffer(_total_start, _total_size); 766 bxp->take_over_code_from(this); // remember the old undersized blob 767 DEBUG_ONLY(this->_blob = NULL); // silence a later assert 768 bxp->_before_expand = this->_before_expand; 769 this->_before_expand = bxp; 770 771 // Give each section its required (expanded) capacity. 772 for (int n = (int)SECT_LIMIT-1; n >= SECT_INSTS; n--) { 773 CodeSection* cb_sect = cb.code_section(n); 774 CodeSection* this_sect = code_section(n); 775 if (new_capacity[n] == 0) continue; // already nulled out 776 if (n > SECT_INSTS) { 777 cb.initialize_section_size(cb_sect, new_capacity[n]); 778 } 779 assert(cb_sect->capacity() >= new_capacity[n], "big enough"); 780 address cb_start = cb_sect->start(); 781 cb_sect->set_end(cb_start + this_sect->size()); 782 if (this_sect->mark() == NULL) { 783 cb_sect->clear_mark(); 784 } else { 785 cb_sect->set_mark(cb_start + this_sect->mark_off()); 786 } 787 } 788 789 // Move all the code and relocations to the new blob: 790 relocate_code_to(&cb); 791 792 // Copy the temporary code buffer into the current code buffer. 793 // Basically, do {*this = cb}, except for some control information. 794 this->take_over_code_from(&cb); 795 cb.set_blob(NULL); 796 797 // Zap the old code buffer contents, to avoid mistakenly using them. 798 debug_only(Copy::fill_to_bytes(bxp->_total_start, bxp->_total_size, 799 badCodeHeapFreeVal)); 800 801 _decode_begin = NULL; // sanity 802 803 // Make certain that the new sections are all snugly inside the new blob. 804 assert(verify_section_allocation(), "expanded allocation is ship-shape"); 805 806#ifndef PRODUCT 807 if (PrintNMethods && (WizardMode || Verbose)) { 808 tty->print("expanded CodeBuffer:"); 809 this->print(); 810 } 811#endif //PRODUCT 812} 813 814void CodeBuffer::take_over_code_from(CodeBuffer* cb) { 815 // Must already have disposed of the old blob somehow. 816 assert(blob() == NULL, "must be empty"); 817#ifdef ASSERT 818 819#endif 820 // Take the new blob away from cb. 821 set_blob(cb->blob()); 822 // Take over all the section pointers. 823 for (int n = 0; n < (int)SECT_LIMIT; n++) { 824 CodeSection* cb_sect = cb->code_section(n); 825 CodeSection* this_sect = code_section(n); 826 this_sect->take_over_code_from(cb_sect); 827 } 828 _overflow_arena = cb->_overflow_arena; 829 // Make sure the old cb won't try to use it or free it. 830 DEBUG_ONLY(cb->_blob = (BufferBlob*)badAddress); 831} 832 833#ifdef ASSERT 834bool CodeBuffer::verify_section_allocation() { 835 address tstart = _total_start; 836 if (tstart == badAddress) return true; // smashed by set_blob(NULL) 837 address tend = tstart + _total_size; 838 if (_blob != NULL) { 839 assert(tstart >= _blob->instructions_begin(), "sanity"); 840 assert(tend <= _blob->instructions_end(), "sanity"); 841 } 842 address tcheck = tstart; // advancing pointer to verify disjointness 843 for (int n = 0; n < (int)SECT_LIMIT; n++) { 844 CodeSection* sect = code_section(n); 845 if (!sect->is_allocated()) continue; 846 assert(sect->start() >= tcheck, "sanity"); 847 tcheck = sect->start(); 848 assert((intptr_t)tcheck % sect->alignment() == 0 849 || sect->is_empty() || _blob == NULL, 850 "start is aligned"); 851 assert(sect->end() >= tcheck, "sanity"); 852 assert(sect->end() <= tend, "sanity"); 853 } 854 return true; 855} 856#endif //ASSERT 857 858#ifndef PRODUCT 859 860void CodeSection::dump() { 861 address ptr = start(); 862 for (csize_t step; ptr < end(); ptr += step) { 863 step = end() - ptr; 864 if (step > jintSize * 4) step = jintSize * 4; 865 tty->print(PTR_FORMAT ": ", ptr); 866 while (step > 0) { 867 tty->print(" " PTR32_FORMAT, *(jint*)ptr); 868 ptr += jintSize; 869 } 870 tty->cr(); 871 } 872} 873 874 875void CodeSection::decode() { 876 Disassembler::decode(start(), end()); 877} 878 879 880void CodeBuffer::block_comment(intptr_t offset, const char * comment) { 881 _comments.add_comment(offset, comment); 882} 883 884 885class CodeComment: public CHeapObj { 886 private: 887 friend class CodeComments; 888 intptr_t _offset; 889 const char * _comment; 890 CodeComment* _next; 891 892 ~CodeComment() { 893 assert(_next == NULL, "wrong interface for freeing list"); 894 os::free((void*)_comment); 895 } 896 897 public: 898 CodeComment(intptr_t offset, const char * comment) { 899 _offset = offset; 900 _comment = os::strdup(comment); 901 _next = NULL; 902 } 903 904 intptr_t offset() const { return _offset; } 905 const char * comment() const { return _comment; } 906 CodeComment* next() { return _next; } 907 908 void set_next(CodeComment* next) { _next = next; } 909 910 CodeComment* find(intptr_t offset) { 911 CodeComment* a = this; 912 while (a != NULL && a->_offset != offset) { 913 a = a->_next; 914 } 915 return a; 916 } 917}; 918 919 920void CodeComments::add_comment(intptr_t offset, const char * comment) { 921 CodeComment* c = new CodeComment(offset, comment); 922 CodeComment* insert = NULL; 923 if (_comments != NULL) { 924 CodeComment* c = _comments->find(offset); 925 insert = c; 926 while (c && c->offset() == offset) { 927 insert = c; 928 c = c->next(); 929 } 930 } 931 if (insert) { 932 // insert after comments with same offset 933 c->set_next(insert->next()); 934 insert->set_next(c); 935 } else { 936 c->set_next(_comments); 937 _comments = c; 938 } 939} 940 941 942void CodeComments::assign(CodeComments& other) { 943 assert(_comments == NULL, "don't overwrite old value"); 944 _comments = other._comments; 945} 946 947 948void CodeComments::print_block_comment(outputStream* stream, intptr_t offset) { 949 if (_comments != NULL) { 950 CodeComment* c = _comments->find(offset); 951 while (c && c->offset() == offset) { 952 stream->bol(); 953 stream->print(" ;; "); 954 stream->print_cr(c->comment()); 955 c = c->next(); 956 } 957 } 958} 959 960 961void CodeComments::free() { 962 CodeComment* n = _comments; 963 while (n) { 964 // unlink the node from the list saving a pointer to the next 965 CodeComment* p = n->_next; 966 n->_next = NULL; 967 delete n; 968 n = p; 969 } 970 _comments = NULL; 971} 972 973 974 975void CodeBuffer::decode() { 976 Disassembler::decode(decode_begin(), code_end()); 977 _decode_begin = code_end(); 978} 979 980 981void CodeBuffer::skip_decode() { 982 _decode_begin = code_end(); 983} 984 985 986void CodeBuffer::decode_all() { 987 for (int n = 0; n < (int)SECT_LIMIT; n++) { 988 // dump contents of each section 989 CodeSection* cs = code_section(n); 990 tty->print_cr("! %s:", code_section_name(n)); 991 if (cs != consts()) 992 cs->decode(); 993 else 994 cs->dump(); 995 } 996} 997 998 999void CodeSection::print(const char* name) { 1000 csize_t locs_size = locs_end() - locs_start(); 1001 tty->print_cr(" %7s.code = " PTR_FORMAT " : " PTR_FORMAT " : " PTR_FORMAT " (%d of %d)%s", 1002 name, start(), end(), limit(), size(), capacity(), 1003 is_frozen()? " [frozen]": ""); 1004 tty->print_cr(" %7s.locs = " PTR_FORMAT " : " PTR_FORMAT " : " PTR_FORMAT " (%d of %d) point=%d", 1005 name, locs_start(), locs_end(), locs_limit(), locs_size, locs_capacity(), locs_point_off()); 1006 if (PrintRelocations) { 1007 RelocIterator iter(this); 1008 iter.print(); 1009 } 1010} 1011 1012void CodeBuffer::print() { 1013 if (this == NULL) { 1014 tty->print_cr("NULL CodeBuffer pointer"); 1015 return; 1016 } 1017 1018 tty->print_cr("CodeBuffer:"); 1019 for (int n = 0; n < (int)SECT_LIMIT; n++) { 1020 // print each section 1021 CodeSection* cs = code_section(n); 1022 cs->print(code_section_name(n)); 1023 } 1024} 1025 1026#endif // PRODUCT 1027