1 /* 2 * Copyright (c) 1997, 2025, 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 Frame_Complete, // Offset in the code where the frame setup is (for forte stackwalks) is complete 57 OSR_Entry, 58 Exceptions, // Offset where exception handler lives 59 Deopt, // Offset where deopt handler lives 60 UnwindHandler, // Offset to default unwind handler 61 max_Entries }; 62 63 // special value to note codeBlobs where profile (forte) stack walking is 64 // always dangerous and suspect. 65 66 enum { frame_never_safe = -1 }; 67 68 private: 69 int _values[max_Entries]; 70 71 public: 72 CodeOffsets() { 73 _values[Entry ] = 0; 74 _values[Verified_Entry] = 0; 75 _values[Frame_Complete] = frame_never_safe; 76 _values[OSR_Entry ] = 0; 77 _values[Exceptions ] = -1; 78 _values[Deopt ] = -1; 79 _values[UnwindHandler ] = -1; 80 } 81 82 int value(Entries e) { return _values[e]; } 83 void set_value(Entries e, int val) { _values[e] = val; } 84 }; 85 86 // This class represents a stream of code and associated relocations. 87 // There are a few in each CodeBuffer. 88 // They are filled concurrently, and concatenated at the end. 89 class CodeSection { 90 friend class CodeBuffer; 91 friend class AOTCodeReader; 92 public: 93 typedef int csize_t; // code size type; would be size_t except for history 94 95 private: 96 address _start; // first byte of contents (instructions) 97 address _mark; // user mark, usually an instruction beginning 98 address _end; // current end address 99 address _limit; // last possible (allocated) end address 100 relocInfo* _locs_start; // first byte of relocation information 101 relocInfo* _locs_end; // first byte after relocation information 102 relocInfo* _locs_limit; // first byte after relocation information buf 103 address _locs_point; // last relocated position (grows upward) 104 bool _locs_own; // did I allocate the locs myself? 105 bool _scratch_emit; // Buffer is used for scratch emit, don't relocate. 106 int _skipped_instructions_size; 107 int8_t _index; // my section number (SECT_INST, etc.) 108 CodeBuffer* _outer; // enclosing CodeBuffer 109 110 // (Note: _locs_point used to be called _last_reloc_offset.) 111 112 CodeSection() { 113 _start = nullptr; 114 _mark = nullptr; 115 _end = nullptr; 116 _limit = nullptr; 117 _locs_start = nullptr; 118 _locs_end = nullptr; 119 _locs_limit = nullptr; 120 _locs_point = nullptr; 121 _locs_own = false; 122 _scratch_emit = false; 123 _skipped_instructions_size = 0; 124 DEBUG_ONLY(_index = -1); 125 DEBUG_ONLY(_outer = (CodeBuffer*)badAddress); 126 } 127 128 void initialize_outer(CodeBuffer* outer, int8_t index) { 129 _outer = outer; 130 _index = index; 131 } 132 133 void initialize(address start, csize_t size = 0) { 134 assert(_start == nullptr, "only one init step, please"); 135 _start = start; 136 _mark = nullptr; 137 _end = start; 138 139 _limit = start + size; 140 _locs_point = start; 141 } 142 143 void initialize_locs(int locs_capacity); 144 void expand_locs(int new_capacity); 145 void initialize_locs_from(const CodeSection* source_cs); 146 147 // helper for CodeBuffer::expand() 148 void take_over_code_from(CodeSection* cs) { 149 _start = cs->_start; 150 _mark = cs->_mark; 151 _end = cs->_end; 152 _limit = cs->_limit; 153 _locs_point = cs->_locs_point; 154 _skipped_instructions_size = cs->_skipped_instructions_size; 155 } 156 157 public: 158 address start() const { return _start; } 159 address mark() const { return _mark; } 160 address end() const { return _end; } 161 address limit() const { return _limit; } 162 csize_t size() const { return (csize_t)(_end - _start); } 163 csize_t mark_off() const { assert(_mark != nullptr, "not an offset"); 164 return (csize_t)(_mark - _start); } 165 csize_t capacity() const { return (csize_t)(_limit - _start); } 166 csize_t remaining() const { return (csize_t)(_limit - _end); } 167 168 relocInfo* locs_start() const { return _locs_start; } 169 relocInfo* locs_end() const { return _locs_end; } 170 int locs_count() const { return (int)(_locs_end - _locs_start); } 171 relocInfo* locs_limit() const { return _locs_limit; } 172 address locs_point() const { return _locs_point; } 173 csize_t locs_point_off() const{ return (csize_t)(_locs_point - _start); } 174 csize_t locs_capacity() const { return (csize_t)(_locs_limit - _locs_start); } 175 176 int8_t index() const { return _index; } 177 bool is_allocated() const { return _start != nullptr; } 178 bool is_empty() const { return _start == _end; } 179 bool has_locs() const { return _locs_end != nullptr; } 180 181 // Mark scratch buffer. 182 void set_scratch_emit() { _scratch_emit = true; } 183 void clear_scratch_emit() { _scratch_emit = false; } 184 bool scratch_emit() { return _scratch_emit; } 185 186 CodeBuffer* outer() const { return _outer; } 187 188 // is a given address in this section? (2nd version is end-inclusive) 189 bool contains(address pc) const { return pc >= _start && pc < _end; } 190 bool contains2(address pc) const { return pc >= _start && pc <= _end; } 191 bool allocates(address pc) const { return pc >= _start && pc < _limit; } 192 bool allocates2(address pc) const { return pc >= _start && pc <= _limit; } 193 194 // checks if two CodeSections are disjoint 195 // 196 // limit is an exclusive address and can be the start of another 197 // section. 198 bool disjoint(CodeSection* cs) const { return cs->_limit <= _start || cs->_start >= _limit; } 199 200 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; } 201 void set_mark(address pc) { assert(contains2(pc), "not in codeBuffer"); 202 _mark = pc; } 203 void set_mark() { _mark = _end; } 204 void clear_mark() { _mark = nullptr; } 205 206 void set_locs_end(relocInfo* p) { 207 assert(p <= locs_limit(), "locs data fits in allocated buffer"); 208 _locs_end = p; 209 } 210 void set_locs_point(address pc) { 211 assert(pc >= locs_point(), "relocation addr may not decrease"); 212 assert(allocates2(pc), "relocation addr " INTPTR_FORMAT " must be in this section from " INTPTR_FORMAT " to " INTPTR_FORMAT, p2i(pc), p2i(_start), p2i(_limit)); 213 _locs_point = pc; 214 } 215 216 void register_skipped(int size) { 217 _skipped_instructions_size += size; 218 } 219 220 // Code emission 221 void emit_int8(uint8_t x1) { 222 address curr = end(); 223 *((uint8_t*) curr++) = x1; 224 set_end(curr); 225 } 226 227 template <typename T> 228 void emit_native(T x) { put_native(end(), x); set_end(end() + sizeof x); } 229 230 void emit_int16(uint16_t x) { emit_native(x); } 231 void emit_int16(uint8_t x1, uint8_t x2) { 232 address curr = end(); 233 *((uint8_t*) curr++) = x1; 234 *((uint8_t*) curr++) = x2; 235 set_end(curr); 236 } 237 238 void emit_int24(uint8_t x1, uint8_t x2, uint8_t x3) { 239 address curr = end(); 240 *((uint8_t*) curr++) = x1; 241 *((uint8_t*) curr++) = x2; 242 *((uint8_t*) curr++) = x3; 243 set_end(curr); 244 } 245 246 void emit_int32(uint32_t x) { emit_native(x); } 247 void emit_int32(uint8_t x1, uint8_t x2, uint8_t x3, uint8_t x4) { 248 address curr = end(); 249 *((uint8_t*) curr++) = x1; 250 *((uint8_t*) curr++) = x2; 251 *((uint8_t*) curr++) = x3; 252 *((uint8_t*) curr++) = x4; 253 set_end(curr); 254 } 255 256 void emit_int64(uint64_t x) { emit_native(x); } 257 void emit_float(jfloat x) { emit_native(x); } 258 void emit_double(jdouble x) { emit_native(x); } 259 void emit_address(address x) { emit_native(x); } 260 261 // Share a scratch buffer for relocinfo. (Hacky; saves a resource allocation.) 262 void initialize_shared_locs(relocInfo* buf, int length); 263 264 // Manage labels and their addresses. 265 address target(Label& L, address branch_pc); 266 267 // Emit a relocation. 268 void relocate(address at, RelocationHolder const& rspec, int format = 0); 269 void relocate(address at, relocInfo::relocType rtype, int format = 0, jint method_index = 0); 270 271 int alignment() const; 272 273 // Slop between sections, used only when allocating temporary BufferBlob buffers. 274 static csize_t end_slop() { return MAX2((int)sizeof(jdouble), (int)CodeEntryAlignment); } 275 276 csize_t align_at_start(csize_t off) const { 277 return (csize_t) align_up(off, alignment()); 278 } 279 280 // Ensure there's enough space left in the current section. 281 // Return true if there was an expansion. 282 bool maybe_expand_to_ensure_remaining(csize_t amount); 283 284 #ifndef PRODUCT 285 void decode(); 286 void print_on(outputStream* st, const char* name); 287 #endif //PRODUCT 288 }; 289 290 291 #ifndef PRODUCT 292 293 // ----- CHeapString ----------------------------------------------------------- 294 295 class CHeapString : public CHeapObj<mtCode> { 296 public: 297 CHeapString(const char* str) : _string(os::strdup(str)) {} 298 ~CHeapString(); 299 const char* string() const { return _string; } 300 301 private: 302 const char* _string; 303 }; 304 305 // ----- AsmRemarkCollection --------------------------------------------------- 306 307 class AsmRemarkCollection : public CHeapObj<mtCode> { 308 public: 309 AsmRemarkCollection() : _ref_cnt(1), _remarks(nullptr), _next(nullptr) {} 310 ~AsmRemarkCollection() { 311 assert(is_empty(), "Must 'clear()' before deleting!"); 312 assert(_ref_cnt == 0, "No uses must remain when deleting!"); 313 } 314 AsmRemarkCollection* reuse() { 315 precond(_ref_cnt > 0); 316 return _ref_cnt++, this; 317 } 318 319 const char* insert(uint offset, const char* remark); 320 const char* lookup(uint offset) const; 321 const char* next(uint offset) const; 322 323 bool is_empty() const { return _remarks == nullptr; } 324 uint clear(); 325 326 template<typename Function> 327 bool iterate(Function function) const { // lambda enabled API 328 if (_remarks != nullptr) { 329 Cell* tmp = _remarks; 330 do { 331 if(!function(tmp->offset, tmp->string())) { 332 return false; 333 } 334 tmp = tmp->next; 335 } while (tmp != _remarks); 336 } 337 return true; 338 } 339 340 private: 341 struct Cell : CHeapString { 342 Cell(const char* remark, uint offset) : 343 CHeapString(remark), offset(offset), prev(nullptr), next(nullptr) {} 344 void push_back(Cell* cell) { 345 Cell* head = this; 346 Cell* tail = prev; 347 tail->next = cell; 348 cell->next = head; 349 cell->prev = tail; 350 prev = cell; 351 } 352 uint offset; 353 Cell* prev; 354 Cell* next; 355 }; 356 uint _ref_cnt; 357 Cell* _remarks; 358 // Using a 'mutable' iteration pointer to allow 'const' on lookup/next (that 359 // does not change the state of the list per se), supportig a simplistic 360 // iteration scheme. 361 mutable Cell* _next; 362 }; 363 364 // ----- DbgStringCollection --------------------------------------------------- 365 366 class DbgStringCollection : public CHeapObj<mtCode> { 367 public: 368 DbgStringCollection() : _ref_cnt(1), _strings(nullptr) {} 369 ~DbgStringCollection() { 370 assert(is_empty(), "Must 'clear()' before deleting!"); 371 assert(_ref_cnt == 0, "No uses must remain when deleting!"); 372 } 373 DbgStringCollection* reuse() { 374 precond(_ref_cnt > 0); 375 return _ref_cnt++, this; 376 } 377 378 const char* insert(const char* str); 379 const char* lookup(const char* str) const; 380 381 bool is_empty() const { return _strings == nullptr; } 382 uint clear(); 383 384 template<typename Function> 385 bool iterate(Function function) const { // lambda enabled API 386 if (_strings != nullptr) { 387 Cell* tmp = _strings; 388 do { 389 if (!function(tmp->string())) { 390 return false; 391 } 392 tmp = tmp->next; 393 } while (tmp != _strings); 394 } 395 return true; 396 } 397 398 private: 399 struct Cell : CHeapString { 400 Cell(const char* dbgstr) : 401 CHeapString(dbgstr), prev(nullptr), next(nullptr) {} 402 void push_back(Cell* cell) { 403 Cell* head = this; 404 Cell* tail = prev; 405 tail->next = cell; 406 cell->next = head; 407 cell->prev = tail; 408 prev = cell; 409 } 410 Cell* prev; 411 Cell* next; 412 }; 413 uint _ref_cnt; 414 Cell* _strings; 415 }; 416 417 // The assumption made here is that most code remarks (or comments) added to 418 // the generated assembly code are unique, i.e. there is very little gain in 419 // trying to share the strings between the different offsets tracked in a 420 // buffer (or blob). 421 422 class AsmRemarks { 423 public: 424 AsmRemarks(); 425 ~AsmRemarks(); 426 427 void init(); 428 429 const char* insert(uint offset, const char* remstr); 430 431 bool is_empty() const; 432 433 void share(const AsmRemarks &src); 434 void clear(); 435 uint print(uint offset, outputStream* strm = tty) const; 436 437 // For testing purposes only. 438 const AsmRemarkCollection* ref() const { return _remarks; } 439 440 template<typename Function> 441 inline bool iterate(Function function) const { return _remarks->iterate(function); } 442 443 private: 444 AsmRemarkCollection* _remarks; 445 }; 446 447 // The assumption made here is that the number of debug strings (with a fixed 448 // address requirement) is a rather small set per compilation unit. 449 450 class DbgStrings { 451 public: 452 DbgStrings(); 453 ~DbgStrings(); 454 455 void init(); 456 457 const char* insert(const char* dbgstr); 458 459 bool is_empty() const; 460 461 void share(const DbgStrings &src); 462 void clear(); 463 464 // For testing purposes only. 465 const DbgStringCollection* ref() const { return _strings; } 466 467 template<typename Function> 468 bool iterate(Function function) const { return _strings->iterate(function); } 469 470 private: 471 DbgStringCollection* _strings; 472 }; 473 #endif // not PRODUCT 474 475 476 #ifdef ASSERT 477 #include "utilities/copy.hpp" 478 479 class Scrubber { 480 public: 481 Scrubber(void* addr, size_t size) : _addr(addr), _size(size) {} 482 ~Scrubber() { 483 Copy::fill_to_bytes(_addr, _size, badResourceValue); 484 } 485 private: 486 void* _addr; 487 size_t _size; 488 }; 489 #endif // ASSERT 490 491 typedef GrowableArray<SharedStubToInterpRequest> SharedStubToInterpRequests; 492 493 // A CodeBuffer describes a memory space into which assembly 494 // code is generated. This memory space usually occupies the 495 // interior of a single BufferBlob, but in some cases it may be 496 // an arbitrary span of memory, even outside the code cache. 497 // 498 // A code buffer comes in two variants: 499 // 500 // (1) A CodeBuffer referring to an already allocated piece of memory: 501 // This is used to direct 'static' code generation (e.g. for interpreter 502 // or stubroutine generation, etc.). This code comes with NO relocation 503 // information. 504 // 505 // (2) A CodeBuffer referring to a piece of memory allocated when the 506 // CodeBuffer is allocated. This is used for nmethod generation. 507 // 508 // The memory can be divided up into several parts called sections. 509 // Each section independently accumulates code (or data) an relocations. 510 // Sections can grow (at the expense of a reallocation of the BufferBlob 511 // and recopying of all active sections). When the buffered code is finally 512 // written to an nmethod (or other CodeBlob), the contents (code, data, 513 // and relocations) of the sections are padded to an alignment and concatenated. 514 // Instructions and data in one section can contain relocatable references to 515 // addresses in a sibling section. 516 517 class CodeBuffer: public StackObj DEBUG_ONLY(COMMA private Scrubber) { 518 friend class CodeSection; 519 friend class StubCodeGenerator; 520 friend class AOTCodeReader; 521 522 private: 523 // CodeBuffers must be allocated on the stack except for a single 524 // special case during expansion which is handled internally. This 525 // is done to guarantee proper cleanup of resources. 526 void* operator new(size_t size) throw() { return resource_allocate_bytes(size); } 527 void operator delete(void* p) { ShouldNotCallThis(); } 528 529 public: 530 typedef int csize_t; // code size type; would be size_t except for history 531 enum : int8_t { 532 // Here is the list of all possible sections. The order reflects 533 // the final layout. 534 SECT_FIRST = 0, 535 SECT_CONSTS = SECT_FIRST, // Non-instruction data: Floats, jump tables, etc. 536 SECT_INSTS, // Executable instructions. 537 SECT_STUBS, // Outbound trampolines for supporting call sites. 538 SECT_LIMIT, SECT_NONE = -1 539 }; 540 541 typedef LinkedListImpl<int> Offsets; 542 typedef ResizeableHashTable<address, Offsets, AnyObj::C_HEAP, mtCompiler> SharedTrampolineRequests; 543 544 private: 545 enum { 546 sect_bits = 2, // assert (SECT_LIMIT <= (1<<sect_bits)) 547 sect_mask = (1<<sect_bits)-1 548 }; 549 550 const char* _name; 551 552 CodeSection _consts; // constants, jump tables 553 CodeSection _insts; // instructions (the main section) 554 CodeSection _stubs; // stubs (call site support), deopt, exception handling 555 556 CodeBuffer* _before_expand; // dead buffer, from before the last expansion 557 558 BufferBlob* _blob; // optional buffer in CodeCache for generated code 559 address _total_start; // first address of combined memory buffer 560 csize_t _total_size; // size in bytes of combined memory buffer 561 562 OopRecorder* _oop_recorder; 563 564 OopRecorder _default_oop_recorder; // override with initialize_oop_recorder 565 Arena* _overflow_arena; 566 567 address _last_insn; // used to merge consecutive memory barriers, loads or stores. 568 address _last_label; // record last bind label address, it's also the start of current bb. 569 570 SharedStubToInterpRequests* _shared_stub_to_interp_requests; // used to collect requests for shared iterpreter stubs 571 SharedTrampolineRequests* _shared_trampoline_requests; // used to collect requests for shared trampolines 572 bool _finalize_stubs; // Indicate if we need to finalize stubs to make CodeBuffer final. 573 574 int _const_section_alignment; 575 576 #ifndef PRODUCT 577 AsmRemarks _asm_remarks; 578 DbgStrings _dbg_strings; 579 bool _collect_comments; // Indicate if we need to collect block comments at all. 580 address _decode_begin; // start address for decode 581 address decode_begin(); 582 #endif 583 584 void initialize_misc(const char * name) { 585 // all pointers other than code_start/end and those inside the sections 586 assert(name != nullptr, "must have a name"); 587 _name = name; 588 _before_expand = nullptr; 589 _blob = nullptr; 590 _total_start = nullptr; 591 _total_size = 0; 592 _oop_recorder = nullptr; 593 _overflow_arena = nullptr; 594 _last_insn = nullptr; 595 _last_label = nullptr; 596 _finalize_stubs = false; 597 _shared_stub_to_interp_requests = nullptr; 598 _shared_trampoline_requests = nullptr; 599 600 _consts.initialize_outer(this, SECT_CONSTS); 601 _insts.initialize_outer(this, SECT_INSTS); 602 _stubs.initialize_outer(this, SECT_STUBS); 603 604 // Default is to align on 8 bytes. A compiler can change this 605 // if larger alignment (e.g., 32-byte vector masks) is required. 606 _const_section_alignment = (int) sizeof(jdouble); 607 608 #ifndef PRODUCT 609 _decode_begin = nullptr; 610 // Collect block comments, but restrict collection to cases where a disassembly is output. 611 _collect_comments = ( PrintAssembly 612 || PrintStubCode 613 || PrintMethodHandleStubs 614 || PrintInterpreter 615 || PrintSignatureHandlers 616 || UnlockDiagnosticVMOptions 617 ); 618 #endif 619 } 620 621 void initialize(address code_start, csize_t code_size) { 622 _total_start = code_start; 623 _total_size = code_size; 624 // Initialize the main section: 625 _insts.initialize(code_start, code_size); 626 assert(!_stubs.is_allocated(), "no garbage here"); 627 assert(!_consts.is_allocated(), "no garbage here"); 628 _oop_recorder = &_default_oop_recorder; 629 } 630 631 void initialize_section_size(CodeSection* cs, csize_t size); 632 633 // helper for CodeBuffer::expand() 634 void take_over_code_from(CodeBuffer* cs); 635 636 // ensure sections are disjoint, ordered, and contained in the blob 637 void verify_section_allocation(); 638 639 // copies combined relocations to the blob, returns bytes copied 640 // (if target is null, it is a dry run only, just for sizing) 641 csize_t copy_relocations_to(CodeBlob* blob) const; 642 csize_t copy_relocations_to(address buf, csize_t buf_limit) const; 643 644 // copies combined code to the blob (assumes relocs are already in there) 645 void copy_code_to(CodeBlob* blob); 646 647 // moves code sections to new buffer (assumes relocs are already in there) 648 void relocate_code_to(CodeBuffer* cb) const; 649 650 // adjust some internal address during expand 651 void adjust_internal_address(address from, address to); 652 653 // set up a model of the final layout of my contents 654 void compute_final_layout(CodeBuffer* dest) const; 655 656 // Expand the given section so at least 'amount' is remaining. 657 // Creates a new, larger BufferBlob, and rewrites the code & relocs. 658 void expand(CodeSection* which_cs, csize_t amount); 659 660 // Helper for expand. 661 csize_t figure_expanded_capacities(CodeSection* which_cs, csize_t amount, csize_t* new_capacity); 662 663 public: 664 // (1) code buffer referring to pre-allocated instruction memory 665 CodeBuffer(address code_start, csize_t code_size) 666 DEBUG_ONLY(: Scrubber(this, sizeof(*this))) 667 { 668 assert(code_start != nullptr, "sanity"); 669 initialize_misc("static buffer"); 670 initialize(code_start, code_size); 671 DEBUG_ONLY(verify_section_allocation();) 672 } 673 674 // (2) CodeBuffer referring to pre-allocated CodeBlob. 675 CodeBuffer(const CodeBlob* blob); 676 677 // (3) code buffer allocating codeBlob memory for code & relocation 678 // info but with lazy initialization. The name must be something 679 // informative. 680 CodeBuffer(const char* name) 681 DEBUG_ONLY(: Scrubber(this, sizeof(*this))) 682 { 683 initialize_misc(name); 684 } 685 686 // (4) code buffer allocating codeBlob memory for code & relocation 687 // info. The name must be something informative and code_size must 688 // include both code and stubs sizes. 689 CodeBuffer(const char* name, csize_t code_size, csize_t locs_size) 690 DEBUG_ONLY(: Scrubber(this, sizeof(*this))) 691 { 692 initialize_misc(name); 693 initialize(code_size, locs_size); 694 } 695 696 ~CodeBuffer(); 697 698 // Initialize a CodeBuffer constructed using constructor 3. Using 699 // constructor 4 is equivalent to calling constructor 3 and then 700 // calling this method. It's been factored out for convenience of 701 // construction. 702 void initialize(csize_t code_size, csize_t locs_size); 703 704 CodeSection* consts() { return &_consts; } 705 CodeSection* insts() { return &_insts; } 706 CodeSection* stubs() { return &_stubs; } 707 708 const CodeSection* insts() const { return &_insts; } 709 710 // present sections in order; return null at end; consts is #0, etc. 711 CodeSection* code_section(int n) { 712 // This makes the slightly questionable but portable assumption 713 // that the various members (_consts, _insts, _stubs, etc.) are 714 // adjacent in the layout of CodeBuffer. 715 CodeSection* cs = &_consts + n; 716 assert(cs->index() == n || !cs->is_allocated(), "sanity"); 717 return cs; 718 } 719 const CodeSection* code_section(int n) const { // yucky const stuff 720 return ((CodeBuffer*)this)->code_section(n); 721 } 722 static const char* code_section_name(int n); 723 int section_index_of(address addr) const; 724 bool contains(address addr) const { 725 // handy for debugging 726 return section_index_of(addr) > SECT_NONE; 727 } 728 729 // A stable mapping between 'locators' (small ints) and addresses. 730 static int locator_pos(int locator) { return locator >> sect_bits; } 731 static int locator_sect(int locator) { return locator & sect_mask; } 732 static int locator(int pos, int sect) { return (pos << sect_bits) | sect; } 733 int locator(address addr) const; 734 address locator_address(int locator) const { 735 if (locator < 0) return nullptr; 736 address start = code_section(locator_sect(locator))->start(); 737 return start + locator_pos(locator); 738 } 739 740 // Heuristic for pre-packing the taken/not-taken bit of a predicted branch. 741 bool is_backward_branch(Label& L); 742 743 // Properties 744 const char* name() const { return _name; } 745 CodeBuffer* before_expand() const { return _before_expand; } 746 BufferBlob* blob() const { return _blob; } 747 void set_blob(BufferBlob* blob); 748 void free_blob(); // Free the blob, if we own one. 749 750 // Properties relative to the insts section: 751 address insts_begin() const { return _insts.start(); } 752 address insts_end() const { return _insts.end(); } 753 void set_insts_end(address end) { _insts.set_end(end); } 754 address insts_mark() const { return _insts.mark(); } 755 void set_insts_mark() { _insts.set_mark(); } 756 757 // is there anything in the buffer other than the current section? 758 bool is_pure() const { return insts_size() == total_content_size(); } 759 760 // size in bytes of output so far in the insts sections 761 csize_t insts_size() const { return _insts.size(); } 762 763 // same as insts_size(), except that it asserts there is no non-code here 764 csize_t pure_insts_size() const { assert(is_pure(), "no non-code"); 765 return insts_size(); } 766 // capacity in bytes of the insts sections 767 csize_t insts_capacity() const { return _insts.capacity(); } 768 769 // number of bytes remaining in the insts section 770 csize_t insts_remaining() const { return _insts.remaining(); } 771 772 // is a given address in the insts section? (2nd version is end-inclusive) 773 bool insts_contains(address pc) const { return _insts.contains(pc); } 774 bool insts_contains2(address pc) const { return _insts.contains2(pc); } 775 776 // Record any extra oops required to keep embedded metadata alive 777 void finalize_oop_references(const methodHandle& method); 778 779 // Allocated size in all sections, when aligned and concatenated 780 // (this is the eventual state of the content in its final 781 // CodeBlob). 782 csize_t total_content_size() const; 783 784 // Combined offset (relative to start of first section) of given 785 // section, as eventually found in the final CodeBlob. 786 csize_t total_offset_of(const CodeSection* cs) const; 787 788 // allocated size of all relocation data, including index, rounded up 789 csize_t total_relocation_size() const; 790 791 int total_skipped_instructions_size() const; 792 793 // allocated size of any and all recorded oops 794 csize_t total_oop_size() const { 795 OopRecorder* recorder = oop_recorder(); 796 return (recorder == nullptr)? 0: recorder->oop_size(); 797 } 798 799 // allocated size of any and all recorded metadata 800 csize_t total_metadata_size() const { 801 OopRecorder* recorder = oop_recorder(); 802 return (recorder == nullptr)? 0: recorder->metadata_size(); 803 } 804 805 // Configuration functions, called immediately after the CB is constructed. 806 // The section sizes are subtracted from the original insts section. 807 // Note: Call them in reverse section order, because each steals from insts. 808 void initialize_consts_size(csize_t size) { initialize_section_size(&_consts, size); } 809 void initialize_stubs_size(csize_t size) { initialize_section_size(&_stubs, size); } 810 // Override default oop recorder. 811 void initialize_oop_recorder(OopRecorder* r); 812 813 OopRecorder* oop_recorder() const { return _oop_recorder; } 814 815 address last_insn() const { return _last_insn; } 816 void set_last_insn(address a) { _last_insn = a; } 817 void clear_last_insn() { set_last_insn(nullptr); } 818 819 address last_label() const { return _last_label; } 820 void set_last_label(address a) { _last_label = a; } 821 822 #ifndef PRODUCT 823 AsmRemarks &asm_remarks() { return _asm_remarks; } 824 DbgStrings &dbg_strings() { return _dbg_strings; } 825 826 void clear_strings() { 827 _asm_remarks.clear(); 828 _dbg_strings.clear(); 829 } 830 #endif 831 832 // Code generation 833 void relocate(address at, RelocationHolder const& rspec, int format = 0) { 834 _insts.relocate(at, rspec, format); 835 } 836 void relocate(address at, relocInfo::relocType rtype, int format = 0) { 837 _insts.relocate(at, rtype, format); 838 } 839 840 // Management of overflow storage for binding of Labels. 841 GrowableArray<int>* create_patch_overflow(); 842 843 // NMethod generation 844 void copy_code_and_locs_to(CodeBlob* blob) { 845 assert(blob != nullptr, "sane"); 846 copy_relocations_to(blob); 847 copy_code_to(blob); 848 } 849 void copy_values_to(nmethod* nm) { 850 if (!oop_recorder()->is_unused()) { 851 oop_recorder()->copy_values_to(nm); 852 } 853 } 854 855 void block_comment(ptrdiff_t offset, const char* comment) PRODUCT_RETURN; 856 const char* code_string(const char* str) PRODUCT_RETURN_(return nullptr;); 857 858 // Log a little info about section usage in the CodeBuffer 859 void log_section_sizes(const char* name); 860 861 // Make a set of stubs final. It can create/optimize stubs. 862 bool finalize_stubs(); 863 864 // Request for a shared stub to the interpreter 865 void shared_stub_to_interp_for(ciMethod* callee, csize_t call_offset); 866 867 void set_const_section_alignment(int align) { 868 _const_section_alignment = align_up(align, HeapWordSize); 869 } 870 871 #ifndef PRODUCT 872 public: 873 // Printing / Decoding 874 // decodes from decode_begin() to code_end() and sets decode_begin to end 875 void decode(); 876 void print_on(outputStream* st); 877 #endif 878 // Directly disassemble code buffer. 879 void decode(address start, address end); 880 881 // The following header contains architecture-specific implementations 882 #include CPU_HEADER(codeBuffer) 883 884 }; 885 886 // A Java method can have calls of Java methods which can be statically bound. 887 // Calls of Java methods need stubs to the interpreter. Calls sharing the same Java method 888 // can share a stub to the interpreter. 889 // A SharedStubToInterpRequest is a request for a shared stub to the interpreter. 890 class SharedStubToInterpRequest : public ResourceObj { 891 private: 892 ciMethod* _shared_method; 893 CodeBuffer::csize_t _call_offset; // The offset of the call in CodeBuffer 894 895 public: 896 SharedStubToInterpRequest(ciMethod* method = nullptr, CodeBuffer::csize_t call_offset = -1) : _shared_method(method), 897 _call_offset(call_offset) {} 898 899 ciMethod* shared_method() const { return _shared_method; } 900 CodeBuffer::csize_t call_offset() const { return _call_offset; } 901 }; 902 903 inline bool CodeSection::maybe_expand_to_ensure_remaining(csize_t amount) { 904 if (remaining() < amount) { _outer->expand(this, amount); return true; } 905 return false; 906 } 907 908 #endif // SHARE_ASM_CODEBUFFER_HPP --- EOF ---