1 /* 2 * Copyright (c) 1997, 2026, 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 #ifndef SHARE_ASM_CODEBUFFER_HPP 26 #define SHARE_ASM_CODEBUFFER_HPP 27 28 #include "code/oopRecorder.hpp" 29 #include "code/relocInfo.hpp" 30 #include "compiler/compiler_globals.hpp" 31 #include "runtime/os.hpp" 32 #include "utilities/align.hpp" 33 #include "utilities/debug.hpp" 34 #include "utilities/growableArray.hpp" 35 #include "utilities/linkedlist.hpp" 36 #include "utilities/macros.hpp" 37 #include "utilities/resizableHashTable.hpp" 38 39 template <typename T> 40 static inline void put_native(address p, T x) { 41 memcpy((void*)p, &x, sizeof x); 42 } 43 44 class PhaseCFG; 45 class Compile; 46 class BufferBlob; 47 class CodeBuffer; 48 class Label; 49 class ciMethod; 50 class SharedStubToInterpRequest; 51 52 class CodeOffsets: public StackObj { 53 public: 54 enum Entries { Entry, 55 Verified_Entry, 56 Inline_Entry, 57 Verified_Inline_Entry, 58 Verified_Inline_Entry_RO, 59 Frame_Complete, // Offset in the code where the frame setup is (for forte stackwalks) is complete 60 OSR_Entry, 61 Exceptions, // Offset where exception handler lives 62 Deopt, // Offset where deopt handler lives 63 UnwindHandler, // Offset to default unwind handler 64 max_Entries }; 65 66 // special value to note codeBlobs where profile (forte) stack walking is 67 // always dangerous and suspect. 68 69 static const int frame_never_safe = -1; 70 static const int no_such_entry_point = -1; 71 72 private: 73 int _values[max_Entries]; 74 void check(int e) const { assert(0 <= e && e < max_Entries, "must be"); } 75 76 public: 77 CodeOffsets() { 78 _values[Entry ] = 0; 79 _values[Verified_Entry] = 0; 80 _values[Inline_Entry ] = 0; 81 _values[Verified_Inline_Entry ] = no_such_entry_point; 82 _values[Verified_Inline_Entry_RO] = no_such_entry_point; 83 _values[Frame_Complete] = frame_never_safe; 84 _values[OSR_Entry ] = 0; 85 _values[Exceptions ] = -1; 86 _values[Deopt ] = -1; 87 _values[UnwindHandler ] = -1; 88 } 89 90 int value(Entries e) const { check(e); return _values[e]; } 91 void set_value(Entries e, int val) { check(e); _values[e] = val; } 92 }; 93 94 // This class represents a stream of code and associated relocations. 95 // There are a few in each CodeBuffer. 96 // They are filled concurrently, and concatenated at the end. 97 class CodeSection { 98 friend class CodeBuffer; 99 friend class AOTCodeReader; 100 public: 101 typedef int csize_t; // code size type; would be size_t except for history 102 103 private: 104 address _start; // first byte of contents (instructions) 105 address _mark; // user mark, usually an instruction beginning 106 address _end; // current end address 107 address _limit; // last possible (allocated) end address 108 relocInfo* _locs_start; // first byte of relocation information 109 relocInfo* _locs_end; // first byte after relocation information 110 relocInfo* _locs_limit; // first byte after relocation information buf 111 address _locs_point; // last relocated position (grows upward) 112 bool _locs_own; // did I allocate the locs myself? 113 bool _scratch_emit; // Buffer is used for scratch emit, don't relocate. 114 int _skipped_instructions_size; 115 int8_t _index; // my section number (SECT_INST, etc.) 116 CodeBuffer* _outer; // enclosing CodeBuffer 117 118 // (Note: _locs_point used to be called _last_reloc_offset.) 119 120 CodeSection() { 121 _start = nullptr; 122 _mark = nullptr; 123 _end = nullptr; 124 _limit = nullptr; 125 _locs_start = nullptr; 126 _locs_end = nullptr; 127 _locs_limit = nullptr; 128 _locs_point = nullptr; 129 _locs_own = false; 130 _scratch_emit = false; 131 _skipped_instructions_size = 0; 132 DEBUG_ONLY(_index = -1); 133 DEBUG_ONLY(_outer = (CodeBuffer*)badAddress); 134 } 135 136 void initialize_outer(CodeBuffer* outer, int8_t index) { 137 _outer = outer; 138 _index = index; 139 } 140 141 void initialize(address start, csize_t size = 0) { 142 assert(_start == nullptr, "only one init step, please"); 143 _start = start; 144 _mark = nullptr; 145 _end = start; 146 147 _limit = start + size; 148 _locs_point = start; 149 } 150 151 void initialize_locs(int locs_capacity); 152 void expand_locs(int new_capacity); 153 void initialize_locs_from(const CodeSection* source_cs); 154 155 // helper for CodeBuffer::expand() 156 void take_over_code_from(CodeSection* cs) { 157 _start = cs->_start; 158 _mark = cs->_mark; 159 _end = cs->_end; 160 _limit = cs->_limit; 161 _locs_point = cs->_locs_point; 162 _skipped_instructions_size = cs->_skipped_instructions_size; 163 } 164 165 public: 166 address start() const { return _start; } 167 address mark() const { return _mark; } 168 address end() const { return _end; } 169 address limit() const { return _limit; } 170 csize_t size() const { return (csize_t)(_end - _start); } 171 csize_t mark_off() const { assert(_mark != nullptr, "not an offset"); 172 return (csize_t)(_mark - _start); } 173 csize_t capacity() const { return (csize_t)(_limit - _start); } 174 csize_t remaining() const { return (csize_t)(_limit - _end); } 175 176 relocInfo* locs_start() const { return _locs_start; } 177 relocInfo* locs_end() const { return _locs_end; } 178 int locs_count() const { return (int)(_locs_end - _locs_start); } 179 relocInfo* locs_limit() const { return _locs_limit; } 180 address locs_point() const { return _locs_point; } 181 csize_t locs_point_off() const{ return (csize_t)(_locs_point - _start); } 182 csize_t locs_capacity() const { return (csize_t)(_locs_limit - _locs_start); } 183 184 int8_t index() const { return _index; } 185 bool is_allocated() const { return _start != nullptr; } 186 bool is_empty() const { return _start == _end; } 187 bool has_locs() const { return _locs_end != nullptr; } 188 189 // Mark scratch buffer. 190 void set_scratch_emit() { _scratch_emit = true; } 191 void clear_scratch_emit() { _scratch_emit = false; } 192 bool scratch_emit() { return _scratch_emit; } 193 194 CodeBuffer* outer() const { return _outer; } 195 196 // is a given address in this section? (2nd version is end-inclusive) 197 bool contains(address pc) const { return pc >= _start && pc < _end; } 198 bool contains2(address pc) const { return pc >= _start && pc <= _end; } 199 bool allocates(address pc) const { return pc >= _start && pc < _limit; } 200 bool allocates2(address pc) const { return pc >= _start && pc <= _limit; } 201 202 // checks if two CodeSections are disjoint 203 // 204 // limit is an exclusive address and can be the start of another 205 // section. 206 bool disjoint(CodeSection* cs) const { return cs->_limit <= _start || cs->_start >= _limit; } 207 208 void set_end(address pc) { assert(allocates2(pc), "not in CodeBuffer memory: " INTPTR_FORMAT " <= " INTPTR_FORMAT " <= " INTPTR_FORMAT, p2i(_start), p2i(pc), p2i(_limit)); _end = pc; } 209 void set_mark(address pc) { assert(contains2(pc), "not in codeBuffer"); 210 _mark = pc; } 211 void set_mark() { _mark = _end; } 212 void clear_mark() { _mark = nullptr; } 213 214 void set_locs_end(relocInfo* p) { 215 assert(p <= locs_limit(), "locs data fits in allocated buffer"); 216 _locs_end = p; 217 } 218 void set_locs_point(address pc) { 219 assert(pc >= locs_point(), "relocation addr may not decrease"); 220 assert(allocates2(pc), "relocation addr " INTPTR_FORMAT " must be in this section from " INTPTR_FORMAT " to " INTPTR_FORMAT, p2i(pc), p2i(_start), p2i(_limit)); 221 _locs_point = pc; 222 } 223 224 void register_skipped(int size) { 225 _skipped_instructions_size += size; 226 } 227 228 // Code emission 229 void emit_int8(uint8_t x1) { 230 address curr = end(); 231 *((uint8_t*) curr++) = x1; 232 set_end(curr); 233 } 234 235 template <typename T> 236 void emit_native(T x) { put_native(end(), x); set_end(end() + sizeof x); } 237 238 void emit_int16(uint16_t x) { emit_native(x); } 239 void emit_int16(uint8_t x1, uint8_t x2) { 240 address curr = end(); 241 *((uint8_t*) curr++) = x1; 242 *((uint8_t*) curr++) = x2; 243 set_end(curr); 244 } 245 246 void emit_int24(uint8_t x1, uint8_t x2, uint8_t x3) { 247 address curr = end(); 248 *((uint8_t*) curr++) = x1; 249 *((uint8_t*) curr++) = x2; 250 *((uint8_t*) curr++) = x3; 251 set_end(curr); 252 } 253 254 void emit_int32(uint32_t x) { emit_native(x); } 255 void emit_int32(uint8_t x1, uint8_t x2, uint8_t x3, uint8_t x4) { 256 address curr = end(); 257 *((uint8_t*) curr++) = x1; 258 *((uint8_t*) curr++) = x2; 259 *((uint8_t*) curr++) = x3; 260 *((uint8_t*) curr++) = x4; 261 set_end(curr); 262 } 263 264 void emit_int64(uint64_t x) { emit_native(x); } 265 void emit_float(jfloat x) { emit_native(x); } 266 void emit_double(jdouble x) { emit_native(x); } 267 void emit_address(address x) { emit_native(x); } 268 269 // Share a scratch buffer for relocinfo. (Hacky; saves a resource allocation.) 270 void initialize_shared_locs(relocInfo* buf, int length); 271 272 // Manage labels and their addresses. 273 address target(Label& L, address branch_pc); 274 275 // Emit a relocation. 276 void relocate(address at, RelocationHolder const& rspec, int format = 0); 277 void relocate(address at, relocInfo::relocType rtype, int format = 0, jint method_index = 0); 278 279 int alignment() const; 280 281 // Slop between sections, used only when allocating temporary BufferBlob buffers. 282 static csize_t end_slop() { return MAX2((int)sizeof(jdouble), (int)CodeEntryAlignment); } 283 284 csize_t align_at_start(csize_t off) const { 285 return (csize_t) align_up(off, alignment()); 286 } 287 288 // Ensure there's enough space left in the current section. 289 // Return true if there was an expansion. 290 bool maybe_expand_to_ensure_remaining(csize_t amount); 291 292 #ifndef PRODUCT 293 void decode(); 294 void print_on(outputStream* st, const char* name); 295 #endif //PRODUCT 296 }; 297 298 299 #ifndef PRODUCT 300 301 // ----- CHeapString ----------------------------------------------------------- 302 303 class CHeapString : public CHeapObj<mtCode> { 304 public: 305 CHeapString(const char* str) : _string(os::strdup(str)) {} 306 ~CHeapString(); 307 const char* string() const { return _string; } 308 309 private: 310 const char* _string; 311 }; 312 313 // ----- AsmRemarkCollection --------------------------------------------------- 314 315 class AsmRemarkCollection : public CHeapObj<mtCode> { 316 public: 317 AsmRemarkCollection() : _ref_cnt(1), _remarks(nullptr), _next(nullptr) {} 318 ~AsmRemarkCollection() { 319 assert(is_empty(), "Must 'clear()' before deleting!"); 320 assert(_ref_cnt == 0, "No uses must remain when deleting!"); 321 } 322 AsmRemarkCollection* reuse() { 323 precond(_ref_cnt > 0); 324 return _ref_cnt++, this; 325 } 326 327 const char* insert(uint offset, const char* remark); 328 const char* lookup(uint offset) const; 329 const char* next(uint offset) const; 330 331 bool is_empty() const { return _remarks == nullptr; } 332 uint clear(); 333 334 template<typename Function> 335 bool iterate(Function function) const { // lambda enabled API 336 if (_remarks != nullptr) { 337 Cell* tmp = _remarks; 338 do { 339 if(!function(tmp->offset, tmp->string())) { 340 return false; 341 } 342 tmp = tmp->next; 343 } while (tmp != _remarks); 344 } 345 return true; 346 } 347 348 private: 349 struct Cell : CHeapString { 350 Cell(const char* remark, uint offset) : 351 CHeapString(remark), offset(offset), prev(nullptr), next(nullptr) {} 352 void push_back(Cell* cell) { 353 Cell* head = this; 354 Cell* tail = prev; 355 tail->next = cell; 356 cell->next = head; 357 cell->prev = tail; 358 prev = cell; 359 } 360 uint offset; 361 Cell* prev; 362 Cell* next; 363 }; 364 uint _ref_cnt; 365 Cell* _remarks; 366 // Using a 'mutable' iteration pointer to allow 'const' on lookup/next (that 367 // does not change the state of the list per se), supportig a simplistic 368 // iteration scheme. 369 mutable Cell* _next; 370 }; 371 372 // ----- DbgStringCollection --------------------------------------------------- 373 374 class DbgStringCollection : public CHeapObj<mtCode> { 375 public: 376 DbgStringCollection() : _ref_cnt(1), _strings(nullptr) {} 377 ~DbgStringCollection() { 378 assert(is_empty(), "Must 'clear()' before deleting!"); 379 assert(_ref_cnt == 0, "No uses must remain when deleting!"); 380 } 381 DbgStringCollection* reuse() { 382 precond(_ref_cnt > 0); 383 return _ref_cnt++, this; 384 } 385 386 const char* insert(const char* str); 387 const char* lookup(const char* str) const; 388 389 bool is_empty() const { return _strings == nullptr; } 390 uint clear(); 391 392 template<typename Function> 393 bool iterate(Function function) const { // lambda enabled API 394 if (_strings != nullptr) { 395 Cell* tmp = _strings; 396 do { 397 if (!function(tmp->string())) { 398 return false; 399 } 400 tmp = tmp->next; 401 } while (tmp != _strings); 402 } 403 return true; 404 } 405 406 private: 407 struct Cell : CHeapString { 408 Cell(const char* dbgstr) : 409 CHeapString(dbgstr), prev(nullptr), next(nullptr) {} 410 void push_back(Cell* cell) { 411 Cell* head = this; 412 Cell* tail = prev; 413 tail->next = cell; 414 cell->next = head; 415 cell->prev = tail; 416 prev = cell; 417 } 418 Cell* prev; 419 Cell* next; 420 }; 421 uint _ref_cnt; 422 Cell* _strings; 423 }; 424 425 // The assumption made here is that most code remarks (or comments) added to 426 // the generated assembly code are unique, i.e. there is very little gain in 427 // trying to share the strings between the different offsets tracked in a 428 // buffer (or blob). 429 430 class AsmRemarks { 431 public: 432 AsmRemarks(); 433 ~AsmRemarks(); 434 435 void init(); 436 437 const char* insert(uint offset, const char* remstr); 438 439 bool is_empty() const; 440 441 void share(const AsmRemarks &src); 442 void clear(); 443 uint print(uint offset, outputStream* strm = tty) const; 444 445 // For testing purposes only. 446 const AsmRemarkCollection* ref() const { return _remarks; } 447 448 template<typename Function> 449 inline bool iterate(Function function) const { return _remarks->iterate(function); } 450 451 private: 452 AsmRemarkCollection* _remarks; 453 }; 454 455 // The assumption made here is that the number of debug strings (with a fixed 456 // address requirement) is a rather small set per compilation unit. 457 458 class DbgStrings { 459 public: 460 DbgStrings(); 461 ~DbgStrings(); 462 463 void init(); 464 465 const char* insert(const char* dbgstr); 466 467 bool is_empty() const; 468 469 void share(const DbgStrings &src); 470 void clear(); 471 472 // For testing purposes only. 473 const DbgStringCollection* ref() const { return _strings; } 474 475 template<typename Function> 476 bool iterate(Function function) const { return _strings->iterate(function); } 477 478 private: 479 DbgStringCollection* _strings; 480 }; 481 #endif // not PRODUCT 482 483 484 #ifdef ASSERT 485 #include "utilities/copy.hpp" 486 487 class Scrubber { 488 public: 489 Scrubber(void* addr, size_t size) : _addr(addr), _size(size) {} 490 ~Scrubber() { 491 Copy::fill_to_bytes(_addr, _size, badResourceValue); 492 } 493 private: 494 void* _addr; 495 size_t _size; 496 }; 497 #endif // ASSERT 498 499 typedef GrowableArray<SharedStubToInterpRequest> SharedStubToInterpRequests; 500 501 // A CodeBuffer describes a memory space into which assembly 502 // code is generated. This memory space usually occupies the 503 // interior of a single BufferBlob, but in some cases it may be 504 // an arbitrary span of memory, even outside the code cache. 505 // 506 // A code buffer comes in two variants: 507 // 508 // (1) A CodeBuffer referring to an already allocated piece of memory: 509 // This is used to direct 'static' code generation (e.g. for interpreter 510 // or stubroutine generation, etc.). This code comes with NO relocation 511 // information. 512 // 513 // (2) A CodeBuffer referring to a piece of memory allocated when the 514 // CodeBuffer is allocated. This is used for nmethod generation. 515 // 516 // The memory can be divided up into several parts called sections. 517 // Each section independently accumulates code (or data) an relocations. 518 // Sections can grow (at the expense of a reallocation of the BufferBlob 519 // and recopying of all active sections). When the buffered code is finally 520 // written to an nmethod (or other CodeBlob), the contents (code, data, 521 // and relocations) of the sections are padded to an alignment and concatenated. 522 // Instructions and data in one section can contain relocatable references to 523 // addresses in a sibling section. 524 525 class CodeBuffer: public StackObj DEBUG_ONLY(COMMA private Scrubber) { 526 friend class CodeSection; 527 friend class StubCodeGenerator; 528 friend class AOTCodeReader; 529 530 private: 531 // CodeBuffers must be allocated on the stack except for a single 532 // special case during expansion which is handled internally. This 533 // is done to guarantee proper cleanup of resources. 534 void* operator new(size_t size) throw() { return resource_allocate_bytes(size); } 535 void operator delete(void* p) { ShouldNotCallThis(); } 536 537 public: 538 typedef int csize_t; // code size type; would be size_t except for history 539 enum : int8_t { 540 // Here is the list of all possible sections. The order reflects 541 // the final layout. 542 SECT_FIRST = 0, 543 SECT_CONSTS = SECT_FIRST, // Non-instruction data: Floats, jump tables, etc. 544 SECT_INSTS, // Executable instructions. 545 SECT_STUBS, // Outbound trampolines for supporting call sites. 546 SECT_LIMIT, SECT_NONE = -1 547 }; 548 549 typedef LinkedListImpl<int> Offsets; 550 typedef ResizeableHashTable<address, Offsets, AnyObj::C_HEAP, mtCompiler> SharedTrampolineRequests; 551 552 private: 553 enum { 554 sect_bits = 2, // assert (SECT_LIMIT <= (1<<sect_bits)) 555 sect_mask = (1<<sect_bits)-1 556 }; 557 558 const char* _name; 559 560 CodeSection _consts; // constants, jump tables 561 CodeSection _insts; // instructions (the main section) 562 CodeSection _stubs; // stubs (call site support), deopt, exception handling 563 564 CodeBuffer* _before_expand; // dead buffer, from before the last expansion 565 566 BufferBlob* _blob; // optional buffer in CodeCache for generated code 567 address _total_start; // first address of combined memory buffer 568 csize_t _total_size; // size in bytes of combined memory buffer 569 570 OopRecorder* _oop_recorder; 571 572 OopRecorder _default_oop_recorder; // override with initialize_oop_recorder 573 Arena* _overflow_arena; 574 575 address _last_insn; // used to merge consecutive memory barriers, loads or stores. 576 address _last_label; // record last bind label address, it's also the start of current bb. 577 578 SharedStubToInterpRequests* _shared_stub_to_interp_requests; // used to collect requests for shared iterpreter stubs 579 SharedTrampolineRequests* _shared_trampoline_requests; // used to collect requests for shared trampolines 580 bool _finalize_stubs; // Indicate if we need to finalize stubs to make CodeBuffer final. 581 582 int _const_section_alignment; 583 584 #ifndef PRODUCT 585 AsmRemarks _asm_remarks; 586 DbgStrings _dbg_strings; 587 bool _collect_comments; // Indicate if we need to collect block comments at all. 588 address _decode_begin; // start address for decode 589 address decode_begin(); 590 #endif 591 592 void initialize_misc(const char * name) { 593 // all pointers other than code_start/end and those inside the sections 594 assert(name != nullptr, "must have a name"); 595 _name = name; 596 _before_expand = nullptr; 597 _blob = nullptr; 598 _total_start = nullptr; 599 _total_size = 0; 600 _oop_recorder = nullptr; 601 _overflow_arena = nullptr; 602 _last_insn = nullptr; 603 _last_label = nullptr; 604 _finalize_stubs = false; 605 _shared_stub_to_interp_requests = nullptr; 606 _shared_trampoline_requests = nullptr; 607 608 _consts.initialize_outer(this, SECT_CONSTS); 609 _insts.initialize_outer(this, SECT_INSTS); 610 _stubs.initialize_outer(this, SECT_STUBS); 611 612 // Default is to align on 8 bytes. A compiler can change this 613 // if larger alignment (e.g., 32-byte vector masks) is required. 614 _const_section_alignment = (int) sizeof(jdouble); 615 616 #ifndef PRODUCT 617 _decode_begin = nullptr; 618 // Collect block comments, but restrict collection to cases where a disassembly is output. 619 _collect_comments = ( PrintAssembly 620 || PrintStubCode 621 || PrintMethodHandleStubs 622 || PrintInterpreter 623 || PrintSignatureHandlers 624 || UnlockDiagnosticVMOptions 625 ); 626 #endif 627 } 628 629 void initialize(address code_start, csize_t code_size) { 630 _total_start = code_start; 631 _total_size = code_size; 632 // Initialize the main section: 633 _insts.initialize(code_start, code_size); 634 assert(!_stubs.is_allocated(), "no garbage here"); 635 assert(!_consts.is_allocated(), "no garbage here"); 636 _oop_recorder = &_default_oop_recorder; 637 } 638 639 void initialize_section_size(CodeSection* cs, csize_t size); 640 641 // helper for CodeBuffer::expand() 642 void take_over_code_from(CodeBuffer* cs); 643 644 // ensure sections are disjoint, ordered, and contained in the blob 645 void verify_section_allocation(); 646 647 // copies combined relocations to the blob, returns bytes copied 648 // (if target is null, it is a dry run only, just for sizing) 649 csize_t copy_relocations_to(CodeBlob* blob) const; 650 csize_t copy_relocations_to(address buf, csize_t buf_limit) const; 651 652 // copies combined code to the blob (assumes relocs are already in there) 653 void copy_code_to(CodeBlob* blob); 654 655 // moves code sections to new buffer (assumes relocs are already in there) 656 void relocate_code_to(CodeBuffer* cb) const; 657 658 // adjust some internal address during expand 659 void adjust_internal_address(address from, address to); 660 661 // set up a model of the final layout of my contents 662 void compute_final_layout(CodeBuffer* dest) const; 663 664 // Expand the given section so at least 'amount' is remaining. 665 // Creates a new, larger BufferBlob, and rewrites the code & relocs. 666 void expand(CodeSection* which_cs, csize_t amount); 667 668 // Helper for expand. 669 csize_t figure_expanded_capacities(CodeSection* which_cs, csize_t amount, csize_t* new_capacity); 670 671 public: 672 // (1) code buffer referring to pre-allocated instruction memory 673 CodeBuffer(address code_start, csize_t code_size) 674 DEBUG_ONLY(: Scrubber(this, sizeof(*this))) 675 { 676 assert(code_start != nullptr, "sanity"); 677 initialize_misc("static buffer"); 678 initialize(code_start, code_size); 679 DEBUG_ONLY(verify_section_allocation();) 680 } 681 682 // (2) CodeBuffer referring to pre-allocated CodeBlob. 683 CodeBuffer(const CodeBlob* blob); 684 685 // (3) code buffer allocating codeBlob memory for code & relocation 686 // info but with lazy initialization. The name must be something 687 // informative. 688 CodeBuffer(const char* name) 689 DEBUG_ONLY(: Scrubber(this, sizeof(*this))) 690 { 691 initialize_misc(name); 692 } 693 694 // (4) code buffer allocating codeBlob memory for code & relocation 695 // info. The name must be something informative and code_size must 696 // include both code and stubs sizes. 697 CodeBuffer(const char* name, csize_t code_size, csize_t locs_size) 698 DEBUG_ONLY(: Scrubber(this, sizeof(*this))) 699 { 700 initialize_misc(name); 701 initialize(code_size, locs_size); 702 } 703 704 ~CodeBuffer(); 705 706 // Initialize a CodeBuffer constructed using constructor 3. Using 707 // constructor 4 is equivalent to calling constructor 3 and then 708 // calling this method. It's been factored out for convenience of 709 // construction. 710 void initialize(csize_t code_size, csize_t locs_size); 711 712 CodeSection* consts() { return &_consts; } 713 CodeSection* insts() { return &_insts; } 714 CodeSection* stubs() { return &_stubs; } 715 716 const CodeSection* insts() const { return &_insts; } 717 718 // present sections in order; return null at end; consts is #0, etc. 719 CodeSection* code_section(int n) { 720 // This makes the slightly questionable but portable assumption 721 // that the various members (_consts, _insts, _stubs, etc.) are 722 // adjacent in the layout of CodeBuffer. 723 CodeSection* cs = &_consts + n; 724 assert(cs->index() == n || !cs->is_allocated(), "sanity"); 725 return cs; 726 } 727 const CodeSection* code_section(int n) const { // yucky const stuff 728 return ((CodeBuffer*)this)->code_section(n); 729 } 730 static const char* code_section_name(int n); 731 int section_index_of(address addr) const; 732 bool contains(address addr) const { 733 // handy for debugging 734 return section_index_of(addr) > SECT_NONE; 735 } 736 737 // A stable mapping between 'locators' (small ints) and addresses. 738 static int locator_pos(int locator) { return locator >> sect_bits; } 739 static int locator_sect(int locator) { return locator & sect_mask; } 740 static int locator(int pos, int sect) { return (pos << sect_bits) | sect; } 741 int locator(address addr) const; 742 address locator_address(int locator) const { 743 if (locator < 0) return nullptr; 744 address start = code_section(locator_sect(locator))->start(); 745 return start + locator_pos(locator); 746 } 747 748 // Heuristic for pre-packing the taken/not-taken bit of a predicted branch. 749 bool is_backward_branch(Label& L); 750 751 // Properties 752 const char* name() const { return _name; } 753 CodeBuffer* before_expand() const { return _before_expand; } 754 BufferBlob* blob() const { return _blob; } 755 void set_blob(BufferBlob* blob); 756 void free_blob(); // Free the blob, if we own one. 757 758 // Properties relative to the insts section: 759 address insts_begin() const { return _insts.start(); } 760 address insts_end() const { return _insts.end(); } 761 void set_insts_end(address end) { _insts.set_end(end); } 762 address insts_mark() const { return _insts.mark(); } 763 void set_insts_mark() { _insts.set_mark(); } 764 765 // is there anything in the buffer other than the current section? 766 bool is_pure() const { return insts_size() == total_content_size(); } 767 768 // size in bytes of output so far in the insts sections 769 csize_t insts_size() const { return _insts.size(); } 770 771 // same as insts_size(), except that it asserts there is no non-code here 772 csize_t pure_insts_size() const { assert(is_pure(), "no non-code"); 773 return insts_size(); } 774 // capacity in bytes of the insts sections 775 csize_t insts_capacity() const { return _insts.capacity(); } 776 777 // number of bytes remaining in the insts section 778 csize_t insts_remaining() const { return _insts.remaining(); } 779 780 // is a given address in the insts section? (2nd version is end-inclusive) 781 bool insts_contains(address pc) const { return _insts.contains(pc); } 782 bool insts_contains2(address pc) const { return _insts.contains2(pc); } 783 784 // Record any extra oops required to keep embedded metadata alive 785 void finalize_oop_references(const methodHandle& method); 786 787 // Allocated size in all sections, when aligned and concatenated 788 // (this is the eventual state of the content in its final 789 // CodeBlob). 790 csize_t total_content_size() const; 791 792 // Combined offset (relative to start of first section) of given 793 // section, as eventually found in the final CodeBlob. 794 csize_t total_offset_of(const CodeSection* cs) const; 795 796 // allocated size of all relocation data, including index, rounded up 797 csize_t total_relocation_size() const; 798 799 int total_skipped_instructions_size() const; 800 801 // allocated size of any and all recorded oops 802 csize_t total_oop_size() const { 803 OopRecorder* recorder = oop_recorder(); 804 return (recorder == nullptr)? 0: recorder->oop_size(); 805 } 806 807 // allocated size of any and all recorded metadata 808 csize_t total_metadata_size() const { 809 OopRecorder* recorder = oop_recorder(); 810 return (recorder == nullptr)? 0: recorder->metadata_size(); 811 } 812 813 // Configuration functions, called immediately after the CB is constructed. 814 // The section sizes are subtracted from the original insts section. 815 // Note: Call them in reverse section order, because each steals from insts. 816 void initialize_consts_size(csize_t size) { initialize_section_size(&_consts, size); } 817 void initialize_stubs_size(csize_t size) { initialize_section_size(&_stubs, size); } 818 // Override default oop recorder. 819 void initialize_oop_recorder(OopRecorder* r); 820 821 OopRecorder* oop_recorder() const { return _oop_recorder; } 822 823 address last_insn() const { return _last_insn; } 824 void set_last_insn(address a) { _last_insn = a; } 825 void clear_last_insn() { set_last_insn(nullptr); } 826 827 address last_label() const { return _last_label; } 828 void set_last_label(address a) { _last_label = a; } 829 830 #ifndef PRODUCT 831 AsmRemarks &asm_remarks() { return _asm_remarks; } 832 DbgStrings &dbg_strings() { return _dbg_strings; } 833 834 void clear_strings() { 835 _asm_remarks.clear(); 836 _dbg_strings.clear(); 837 } 838 #endif 839 840 // Code generation 841 void relocate(address at, RelocationHolder const& rspec, int format = 0) { 842 _insts.relocate(at, rspec, format); 843 } 844 void relocate(address at, relocInfo::relocType rtype, int format = 0) { 845 _insts.relocate(at, rtype, format); 846 } 847 848 // Management of overflow storage for binding of Labels. 849 GrowableArray<int>* create_patch_overflow(); 850 851 // NMethod generation 852 void copy_code_and_locs_to(CodeBlob* blob) { 853 assert(blob != nullptr, "sane"); 854 copy_relocations_to(blob); 855 copy_code_to(blob); 856 } 857 void copy_values_to(nmethod* nm) { 858 if (!oop_recorder()->is_unused()) { 859 oop_recorder()->copy_values_to(nm); 860 } 861 } 862 863 void block_comment(ptrdiff_t offset, const char* comment) PRODUCT_RETURN; 864 const char* code_string(const char* str) PRODUCT_RETURN_(return nullptr;); 865 866 // Log a little info about section usage in the CodeBuffer 867 void log_section_sizes(const char* name); 868 869 // Make a set of stubs final. It can create/optimize stubs. 870 bool finalize_stubs(); 871 872 // Request for a shared stub to the interpreter 873 void shared_stub_to_interp_for(ciMethod* callee, csize_t call_offset); 874 875 void set_const_section_alignment(int align) { 876 _const_section_alignment = align_up(align, HeapWordSize); 877 } 878 879 #ifndef PRODUCT 880 public: 881 // Printing / Decoding 882 // decodes from decode_begin() to code_end() and sets decode_begin to end 883 void decode(); 884 void print_on(outputStream* st); 885 #endif 886 // Directly disassemble code buffer. 887 void decode(address start, address end); 888 889 // The following header contains architecture-specific implementations 890 #include CPU_HEADER(codeBuffer) 891 892 }; 893 894 // A Java method can have calls of Java methods which can be statically bound. 895 // Calls of Java methods need stubs to the interpreter. Calls sharing the same Java method 896 // can share a stub to the interpreter. 897 // A SharedStubToInterpRequest is a request for a shared stub to the interpreter. 898 class SharedStubToInterpRequest : public ResourceObj { 899 private: 900 ciMethod* _shared_method; 901 CodeBuffer::csize_t _call_offset; // The offset of the call in CodeBuffer 902 903 public: 904 SharedStubToInterpRequest(ciMethod* method = nullptr, CodeBuffer::csize_t call_offset = -1) : _shared_method(method), 905 _call_offset(call_offset) {} 906 907 ciMethod* shared_method() const { return _shared_method; } 908 CodeBuffer::csize_t call_offset() const { return _call_offset; } 909 }; 910 911 inline bool CodeSection::maybe_expand_to_ensure_remaining(csize_t amount) { 912 if (remaining() < amount) { _outer->expand(this, amount); return true; } 913 return false; 914 } 915 916 #endif // SHARE_ASM_CODEBUFFER_HPP --- EOF ---