codeBuffer.hpp revision 0:a61af66fc99e
1/* 2 * Copyright 1997-2006 Sun Microsystems, Inc. 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, 20 * CA 95054 USA or visit www.sun.com if you need additional information or 21 * have any questions. 22 * 23 */ 24 25class CodeComments; 26class AbstractAssembler; 27class MacroAssembler; 28class PhaseCFG; 29class Compile; 30class BufferBlob; 31class CodeBuffer; 32 33class CodeOffsets: public StackObj { 34public: 35 enum Entries { Entry, 36 Verified_Entry, 37 Frame_Complete, // Offset in the code where the frame setup is (for forte stackwalks) is complete 38 OSR_Entry, 39 Exceptions, // Offset where exception handler lives 40 Deopt, // Offset where deopt handler lives 41 max_Entries }; 42 43 // special value to note codeBlobs where profile (forte) stack walking is 44 // always dangerous and suspect. 45 46 enum { frame_never_safe = -1 }; 47 48private: 49 int _values[max_Entries]; 50 51public: 52 CodeOffsets() { 53 _values[Entry] = 0; 54 _values[Verified_Entry] = 0; 55 _values[Frame_Complete] = frame_never_safe; 56 _values[OSR_Entry] = 0; 57 _values[Exceptions] = -1; 58 _values[Deopt] = -1; 59 } 60 61 int value(Entries e) { return _values[e]; } 62 void set_value(Entries e, int val) { _values[e] = val; } 63}; 64 65// This class represents a stream of code and associated relocations. 66// There are a few in each CodeBuffer. 67// They are filled concurrently, and concatenated at the end. 68class CodeSection VALUE_OBJ_CLASS_SPEC { 69 friend class CodeBuffer; 70 public: 71 typedef int csize_t; // code size type; would be size_t except for history 72 73 private: 74 address _start; // first byte of contents (instructions) 75 address _mark; // user mark, usually an instruction beginning 76 address _end; // current end address 77 address _limit; // last possible (allocated) end address 78 relocInfo* _locs_start; // first byte of relocation information 79 relocInfo* _locs_end; // first byte after relocation information 80 relocInfo* _locs_limit; // first byte after relocation information buf 81 address _locs_point; // last relocated position (grows upward) 82 bool _locs_own; // did I allocate the locs myself? 83 bool _frozen; // no more expansion of this section 84 char _index; // my section number (SECT_INST, etc.) 85 CodeBuffer* _outer; // enclosing CodeBuffer 86 87 // (Note: _locs_point used to be called _last_reloc_offset.) 88 89 CodeSection() { 90 _start = NULL; 91 _mark = NULL; 92 _end = NULL; 93 _limit = NULL; 94 _locs_start = NULL; 95 _locs_end = NULL; 96 _locs_limit = NULL; 97 _locs_point = NULL; 98 _locs_own = false; 99 _frozen = false; 100 debug_only(_index = -1); 101 debug_only(_outer = (CodeBuffer*)badAddress); 102 } 103 104 void initialize_outer(CodeBuffer* outer, int index) { 105 _outer = outer; 106 _index = index; 107 } 108 109 void initialize(address start, csize_t size = 0) { 110 assert(_start == NULL, "only one init step, please"); 111 _start = start; 112 _mark = NULL; 113 _end = start; 114 115 _limit = start + size; 116 _locs_point = start; 117 } 118 119 void initialize_locs(int locs_capacity); 120 void expand_locs(int new_capacity); 121 void initialize_locs_from(const CodeSection* source_cs); 122 123 // helper for CodeBuffer::expand() 124 void take_over_code_from(CodeSection* cs) { 125 _start = cs->_start; 126 _mark = cs->_mark; 127 _end = cs->_end; 128 _limit = cs->_limit; 129 _locs_point = cs->_locs_point; 130 } 131 132 public: 133 address start() const { return _start; } 134 address mark() const { return _mark; } 135 address end() const { return _end; } 136 address limit() const { return _limit; } 137 csize_t size() const { return (csize_t)(_end - _start); } 138 csize_t mark_off() const { assert(_mark != NULL, "not an offset"); 139 return (csize_t)(_mark - _start); } 140 csize_t capacity() const { return (csize_t)(_limit - _start); } 141 csize_t remaining() const { return (csize_t)(_limit - _end); } 142 143 relocInfo* locs_start() const { return _locs_start; } 144 relocInfo* locs_end() const { return _locs_end; } 145 int locs_count() const { return (int)(_locs_end - _locs_start); } 146 relocInfo* locs_limit() const { return _locs_limit; } 147 address locs_point() const { return _locs_point; } 148 csize_t locs_point_off() const{ return (csize_t)(_locs_point - _start); } 149 csize_t locs_capacity() const { return (csize_t)(_locs_limit - _locs_start); } 150 csize_t locs_remaining()const { return (csize_t)(_locs_limit - _locs_end); } 151 152 int index() const { return _index; } 153 bool is_allocated() const { return _start != NULL; } 154 bool is_empty() const { return _start == _end; } 155 bool is_frozen() const { return _frozen; } 156 bool has_locs() const { return _locs_end != NULL; } 157 158 CodeBuffer* outer() const { return _outer; } 159 160 // is a given address in this section? (2nd version is end-inclusive) 161 bool contains(address pc) const { return pc >= _start && pc < _end; } 162 bool contains2(address pc) const { return pc >= _start && pc <= _end; } 163 bool allocates(address pc) const { return pc >= _start && pc < _limit; } 164 bool allocates2(address pc) const { return pc >= _start && pc <= _limit; } 165 166 void set_end(address pc) { assert(allocates2(pc),""); _end = pc; } 167 void set_mark(address pc) { assert(contains2(pc),"not in codeBuffer"); 168 _mark = pc; } 169 void set_mark_off(int offset) { assert(contains2(offset+_start),"not in codeBuffer"); 170 _mark = offset + _start; } 171 void set_mark() { _mark = _end; } 172 void clear_mark() { _mark = NULL; } 173 174 void set_locs_end(relocInfo* p) { 175 assert(p <= locs_limit(), "locs data fits in allocated buffer"); 176 _locs_end = p; 177 } 178 void set_locs_point(address pc) { 179 assert(pc >= locs_point(), "relocation addr may not decrease"); 180 assert(allocates2(pc), "relocation addr must be in this section"); 181 _locs_point = pc; 182 } 183 184 // Share a scratch buffer for relocinfo. (Hacky; saves a resource allocation.) 185 void initialize_shared_locs(relocInfo* buf, int length); 186 187 // Manage labels and their addresses. 188 address target(Label& L, address branch_pc); 189 190 // Emit a relocation. 191 void relocate(address at, RelocationHolder const& rspec, int format = 0); 192 void relocate(address at, relocInfo::relocType rtype, int format = 0) { 193 if (rtype != relocInfo::none) 194 relocate(at, Relocation::spec_simple(rtype), format); 195 } 196 197 // alignment requirement for starting offset 198 // Requirements are that the instruction area and the 199 // stubs area must start on CodeEntryAlignment, and 200 // the ctable on sizeof(jdouble) 201 int alignment() const { return MAX2((int)sizeof(jdouble), (int)CodeEntryAlignment); } 202 203 // Slop between sections, used only when allocating temporary BufferBlob buffers. 204 static csize_t end_slop() { return MAX2((int)sizeof(jdouble), (int)CodeEntryAlignment); } 205 206 csize_t align_at_start(csize_t off) const { return (csize_t) align_size_up(off, alignment()); } 207 208 // Mark a section frozen. Assign its remaining space to 209 // the following section. It will never expand after this point. 210 inline void freeze(); // { _outer->freeze_section(this); } 211 212 // Ensure there's enough space left in the current section. 213 // Return true if there was an expansion. 214 bool maybe_expand_to_ensure_remaining(csize_t amount); 215 216#ifndef PRODUCT 217 void decode(); 218 void dump(); 219 void print(const char* name); 220#endif //PRODUCT 221}; 222 223class CodeComment; 224class CodeComments VALUE_OBJ_CLASS_SPEC { 225private: 226#ifndef PRODUCT 227 CodeComment* _comments; 228#endif 229 230public: 231 CodeComments() { 232#ifndef PRODUCT 233 _comments = NULL; 234#endif 235 } 236 237 void add_comment(intptr_t offset, const char * comment) PRODUCT_RETURN; 238 void print_block_comment(outputStream* stream, intptr_t offset) PRODUCT_RETURN; 239 void assign(CodeComments& other) PRODUCT_RETURN; 240 void free() PRODUCT_RETURN; 241}; 242 243 244// A CodeBuffer describes a memory space into which assembly 245// code is generated. This memory space usually occupies the 246// interior of a single BufferBlob, but in some cases it may be 247// an arbitrary span of memory, even outside the code cache. 248// 249// A code buffer comes in two variants: 250// 251// (1) A CodeBuffer referring to an already allocated piece of memory: 252// This is used to direct 'static' code generation (e.g. for interpreter 253// or stubroutine generation, etc.). This code comes with NO relocation 254// information. 255// 256// (2) A CodeBuffer referring to a piece of memory allocated when the 257// CodeBuffer is allocated. This is used for nmethod generation. 258// 259// The memory can be divided up into several parts called sections. 260// Each section independently accumulates code (or data) an relocations. 261// Sections can grow (at the expense of a reallocation of the BufferBlob 262// and recopying of all active sections). When the buffered code is finally 263// written to an nmethod (or other CodeBlob), the contents (code, data, 264// and relocations) of the sections are padded to an alignment and concatenated. 265// Instructions and data in one section can contain relocatable references to 266// addresses in a sibling section. 267 268class CodeBuffer: public StackObj { 269 friend class CodeSection; 270 271 private: 272 // CodeBuffers must be allocated on the stack except for a single 273 // special case during expansion which is handled internally. This 274 // is done to guarantee proper cleanup of resources. 275 void* operator new(size_t size) { return ResourceObj::operator new(size); } 276 void operator delete(void* p) { ResourceObj::operator delete(p); } 277 278 public: 279 typedef int csize_t; // code size type; would be size_t except for history 280 enum { 281 // Here is the list of all possible sections, in order of ascending address. 282 SECT_INSTS, // Executable instructions. 283 SECT_STUBS, // Outbound trampolines for supporting call sites. 284 SECT_CONSTS, // Non-instruction data: Floats, jump tables, etc. 285 SECT_LIMIT, SECT_NONE = -1 286 }; 287 288 private: 289 enum { 290 sect_bits = 2, // assert (SECT_LIMIT <= (1<<sect_bits)) 291 sect_mask = (1<<sect_bits)-1 292 }; 293 294 const char* _name; 295 296 CodeSection _insts; // instructions (the main section) 297 CodeSection _stubs; // stubs (call site support), deopt, exception handling 298 CodeSection _consts; // constants, jump tables 299 300 CodeBuffer* _before_expand; // dead buffer, from before the last expansion 301 302 BufferBlob* _blob; // optional buffer in CodeCache for generated code 303 address _total_start; // first address of combined memory buffer 304 csize_t _total_size; // size in bytes of combined memory buffer 305 306 OopRecorder* _oop_recorder; 307 CodeComments _comments; 308 OopRecorder _default_oop_recorder; // override with initialize_oop_recorder 309 Arena* _overflow_arena; 310 311 address _decode_begin; // start address for decode 312 address decode_begin(); 313 314 void initialize_misc(const char * name) { 315 // all pointers other than code_start/end and those inside the sections 316 assert(name != NULL, "must have a name"); 317 _name = name; 318 _before_expand = NULL; 319 _blob = NULL; 320 _oop_recorder = NULL; 321 _decode_begin = NULL; 322 _overflow_arena = NULL; 323 } 324 325 void initialize(address code_start, csize_t code_size) { 326 _insts.initialize_outer(this, SECT_INSTS); 327 _stubs.initialize_outer(this, SECT_STUBS); 328 _consts.initialize_outer(this, SECT_CONSTS); 329 _total_start = code_start; 330 _total_size = code_size; 331 // Initialize the main section: 332 _insts.initialize(code_start, code_size); 333 assert(!_stubs.is_allocated(), "no garbage here"); 334 assert(!_consts.is_allocated(), "no garbage here"); 335 _oop_recorder = &_default_oop_recorder; 336 } 337 338 void initialize_section_size(CodeSection* cs, csize_t size); 339 340 void freeze_section(CodeSection* cs); 341 342 // helper for CodeBuffer::expand() 343 void take_over_code_from(CodeBuffer* cs); 344 345#ifdef ASSERT 346 // ensure sections are disjoint, ordered, and contained in the blob 347 bool verify_section_allocation(); 348#endif 349 350 // copies combined relocations to the blob, returns bytes copied 351 // (if target is null, it is a dry run only, just for sizing) 352 csize_t copy_relocations_to(CodeBlob* blob) const; 353 354 // copies combined code to the blob (assumes relocs are already in there) 355 void copy_code_to(CodeBlob* blob); 356 357 // moves code sections to new buffer (assumes relocs are already in there) 358 void relocate_code_to(CodeBuffer* cb) const; 359 360 // set up a model of the final layout of my contents 361 void compute_final_layout(CodeBuffer* dest) const; 362 363 // Expand the given section so at least 'amount' is remaining. 364 // Creates a new, larger BufferBlob, and rewrites the code & relocs. 365 void expand(CodeSection* which_cs, csize_t amount); 366 367 // Helper for expand. 368 csize_t figure_expanded_capacities(CodeSection* which_cs, csize_t amount, csize_t* new_capacity); 369 370 public: 371 // (1) code buffer referring to pre-allocated instruction memory 372 CodeBuffer(address code_start, csize_t code_size); 373 374 // (2) code buffer allocating codeBlob memory for code & relocation 375 // info but with lazy initialization. The name must be something 376 // informative. 377 CodeBuffer(const char* name) { 378 initialize_misc(name); 379 } 380 381 382 // (3) code buffer allocating codeBlob memory for code & relocation 383 // info. The name must be something informative and code_size must 384 // include both code and stubs sizes. 385 CodeBuffer(const char* name, csize_t code_size, csize_t locs_size) { 386 initialize_misc(name); 387 initialize(code_size, locs_size); 388 } 389 390 ~CodeBuffer(); 391 392 // Initialize a CodeBuffer constructed using constructor 2. Using 393 // constructor 3 is equivalent to calling constructor 2 and then 394 // calling this method. It's been factored out for convenience of 395 // construction. 396 void initialize(csize_t code_size, csize_t locs_size); 397 398 CodeSection* insts() { return &_insts; } 399 CodeSection* stubs() { return &_stubs; } 400 CodeSection* consts() { return &_consts; } 401 402 // present sections in order; return NULL at end; insts is #0, etc. 403 CodeSection* code_section(int n) { 404 // This makes the slightly questionable but portable assumption that 405 // the various members (_insts, _stubs, etc.) are adjacent in the 406 // layout of CodeBuffer. 407 CodeSection* cs = &_insts + n; 408 assert(cs->index() == n || !cs->is_allocated(), "sanity"); 409 return cs; 410 } 411 const CodeSection* code_section(int n) const { // yucky const stuff 412 return ((CodeBuffer*)this)->code_section(n); 413 } 414 static const char* code_section_name(int n); 415 int section_index_of(address addr) const; 416 bool contains(address addr) const { 417 // handy for debugging 418 return section_index_of(addr) > SECT_NONE; 419 } 420 421 // A stable mapping between 'locators' (small ints) and addresses. 422 static int locator_pos(int locator) { return locator >> sect_bits; } 423 static int locator_sect(int locator) { return locator & sect_mask; } 424 static int locator(int pos, int sect) { return (pos << sect_bits) | sect; } 425 int locator(address addr) const; 426 address locator_address(int locator) const; 427 428 // Properties 429 const char* name() const { return _name; } 430 CodeBuffer* before_expand() const { return _before_expand; } 431 BufferBlob* blob() const { return _blob; } 432 void set_blob(BufferBlob* blob); 433 void free_blob(); // Free the blob, if we own one. 434 435 // Properties relative to the insts section: 436 address code_begin() const { return _insts.start(); } 437 address code_end() const { return _insts.end(); } 438 void set_code_end(address end) { _insts.set_end(end); } 439 address code_limit() const { return _insts.limit(); } 440 address inst_mark() const { return _insts.mark(); } 441 void set_inst_mark() { _insts.set_mark(); } 442 void clear_inst_mark() { _insts.clear_mark(); } 443 444 // is there anything in the buffer other than the current section? 445 bool is_pure() const { return code_size() == total_code_size(); } 446 447 // size in bytes of output so far in the insts sections 448 csize_t code_size() const { return _insts.size(); } 449 450 // same as code_size(), except that it asserts there is no non-code here 451 csize_t pure_code_size() const { assert(is_pure(), "no non-code"); 452 return code_size(); } 453 // capacity in bytes of the insts sections 454 csize_t code_capacity() const { return _insts.capacity(); } 455 456 // number of bytes remaining in the insts section 457 csize_t code_remaining() const { return _insts.remaining(); } 458 459 // is a given address in the insts section? (2nd version is end-inclusive) 460 bool code_contains(address pc) const { return _insts.contains(pc); } 461 bool code_contains2(address pc) const { return _insts.contains2(pc); } 462 463 // allocated size of code in all sections, when aligned and concatenated 464 // (this is the eventual state of the code in its final CodeBlob) 465 csize_t total_code_size() const; 466 467 // combined offset (relative to start of insts) of given address, 468 // as eventually found in the final CodeBlob 469 csize_t total_offset_of(address addr) const; 470 471 // allocated size of all relocation data, including index, rounded up 472 csize_t total_relocation_size() const; 473 474 // allocated size of any and all recorded oops 475 csize_t total_oop_size() const { 476 OopRecorder* recorder = oop_recorder(); 477 return (recorder == NULL)? 0: recorder->oop_size(); 478 } 479 480 // Configuration functions, called immediately after the CB is constructed. 481 // The section sizes are subtracted from the original insts section. 482 // Note: Call them in reverse section order, because each steals from insts. 483 void initialize_consts_size(csize_t size) { initialize_section_size(&_consts, size); } 484 void initialize_stubs_size(csize_t size) { initialize_section_size(&_stubs, size); } 485 // Override default oop recorder. 486 void initialize_oop_recorder(OopRecorder* r); 487 488 OopRecorder* oop_recorder() const { return _oop_recorder; } 489 CodeComments& comments() { return _comments; } 490 491 // Code generation 492 void relocate(address at, RelocationHolder const& rspec, int format = 0) { 493 _insts.relocate(at, rspec, format); 494 } 495 void relocate(address at, relocInfo::relocType rtype, int format = 0) { 496 _insts.relocate(at, rtype, format); 497 } 498 499 // Management of overflow storage for binding of Labels. 500 GrowableArray<int>* create_patch_overflow(); 501 502 // NMethod generation 503 void copy_code_and_locs_to(CodeBlob* blob) { 504 assert(blob != NULL, "sane"); 505 copy_relocations_to(blob); 506 copy_code_to(blob); 507 } 508 void copy_oops_to(CodeBlob* blob) { 509 if (!oop_recorder()->is_unused()) { 510 oop_recorder()->copy_to(blob); 511 } 512 } 513 514 // Transform an address from the code in this code buffer to a specified code buffer 515 address transform_address(const CodeBuffer &cb, address addr) const; 516 517 void block_comment(intptr_t offset, const char * comment) PRODUCT_RETURN; 518 519#ifndef PRODUCT 520 public: 521 // Printing / Decoding 522 // decodes from decode_begin() to code_end() and sets decode_begin to end 523 void decode(); 524 void decode_all(); // decodes all the code 525 void skip_decode(); // sets decode_begin to code_end(); 526 void print(); 527#endif 528 529 530 // The following header contains architecture-specific implementations 531 #include "incls/_codeBuffer_pd.hpp.incl" 532}; 533 534 535inline void CodeSection::freeze() { 536 _outer->freeze_section(this); 537} 538 539inline bool CodeSection::maybe_expand_to_ensure_remaining(csize_t amount) { 540 if (remaining() < amount) { _outer->expand(this, amount); return true; } 541 return false; 542} 543