relocInfo.hpp (original) (raw)

1 /* 2 * Copyright (c) 1997, 2013, 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_VM_CODE_RELOCINFO_HPP 26 #define SHARE_VM_CODE_RELOCINFO_HPP 27 28 #include "memory/allocation.hpp" 29 #include "utilities/top.hpp" 30 31 class NativeMovConstReg; 32 33 // Types in this file: 34 // relocInfo 35 // One element of an array of halfwords encoding compressed relocations. 36 // Also, the source of relocation types (relocInfo::oop_type, ...). 37 // Relocation 38 // A flyweight object representing a single relocation. 39 // It is fully unpacked from the compressed relocation array. 40 // metadata_Relocation, ... (subclasses of Relocation) 41 // The location of some type-specific operations (metadata_addr, ...). 42 // Also, the source of relocation specs (metadata_Relocation::spec, ...). 43 // oop_Relocation, ... (subclasses of Relocation) 44 // oops in the code stream (strings, class loaders) 45 // Also, the source of relocation specs (oop_Relocation::spec, ...). 46 // RelocationHolder 47 // A ValueObj type which acts as a union holding a Relocation object. 48 // Represents a relocation spec passed into a CodeBuffer during assembly. 49 // RelocIterator 50 // A StackObj which iterates over the relocations associated with 51 // a range of code addresses. Can be used to operate a copy of code. 52 // BoundRelocation 53 // An internal type shared by packers and unpackers of relocations. 54 // It pastes together a RelocationHolder with some pointers into 55 // code and relocInfo streams. 56 57 58 // Notes on relocType: 59 // 60 // These hold enough information to read or write a value embedded in 61 // the instructions of an CodeBlob. They're used to update: 62 // 63 // 1) embedded oops (isOop() == true) 64 // 2) inline caches (isIC() == true) 65 // 3) runtime calls (isRuntimeCall() == true) 66 // 4) internal word ref (isInternalWord() == true) 67 // 5) external word ref (isExternalWord() == true) 68 // 69 // when objects move (GC) or if code moves (compacting the code heap). 70 // They are also used to patch the code (if a call site must change) 71 // 72 // A relocInfo is represented in 16 bits: 73 // 4 bits indicating the relocation type 74 // 12 bits indicating the offset from the previous relocInfo address 75 // 76 // The offsets accumulate along the relocInfo stream to encode the 77 // address within the CodeBlob, which is named RelocIterator::addr(). 78 // The address of a particular relocInfo always points to the first 79 // byte of the relevant instruction (and not to any of its subfields 80 // or embedded immediate constants). 81 // 82 // The offset value is scaled appropriately for the target machine. 83 // (See relocInfo_.hpp for the offset scaling.) 84 // 85 // On some machines, there may also be a "format" field which may provide 86 // additional information about the format of the instruction stream 87 // at the corresponding code address. The format value is usually zero. 88 // Any machine (such as Intel) whose instructions can sometimes contain 89 // more than one relocatable constant needs format codes to distinguish 90 // which operand goes with a given relocation. 91 // 92 // If the target machine needs N format bits, the offset has 12-N bits, 93 // the format is encoded between the offset and the type, and the 94 // relocInfo_.hpp file has manifest constants for the format codes. 95 // 96 // If the type is "data_prefix_tag" then the offset bits are further encoded, 97 // and in fact represent not a code-stream offset but some inline data. 98 // The data takes the form of a counted sequence of halfwords, which 99 // precedes the actual relocation record. (Clients never see it directly.) 100 // The interpetation of this extra data depends on the relocation type. 101 // 102 // On machines that have 32-bit immediate fields, there is usually 103 // little need for relocation "prefix" data, because the instruction stream 104 // is a perfectly reasonable place to store the value. On machines in 105 // which 32-bit values must be "split" across instructions, the relocation 106 // data is the "true" specification of the value, which is then applied 107 // to some field of the instruction (22 or 13 bits, on SPARC). 108 // 109 // Whenever the location of the CodeBlob changes, any PC-relative 110 // relocations, and any internal_word_type relocations, must be reapplied. 111 // After the GC runs, oop_type relocations must be reapplied. 112 // 113 // 114 // Here are meanings of the types: 115 // 116 // relocInfo::none -- a filler record 117 // Value: none 118 // Instruction: The corresponding code address is ignored 119 // Data: Any data prefix and format code are ignored 120 // (This means that any relocInfo can be disabled by setting 121 // its type to none. See relocInfo::remove.) 122 // 123 // relocInfo::oop_type, relocInfo::metadata_type -- a reference to an oop or meta data 124 // Value: an oop, or else the address (handle) of an oop 125 // Instruction types: memory (load), set (load address) 126 // Data: [] an oop stored in 4 bytes of instruction 127 // [n] n is the index of an oop in the CodeBlob's oop pool 128 // [[N]n l] and l is a byte offset to be applied to the oop 129 // [Nn Ll] both index and offset may be 32 bits if necessary 130 // Here is a special hack, used only by the old compiler: 131 // [[N]n 00] the value is the address of the nth oop in the pool 132 // (Note that the offset allows optimal references to class variables.) 133 // 134 // relocInfo::internal_word_type -- an address within the same CodeBlob 135 // relocInfo::section_word_type -- same, but can refer to another section 136 // Value: an address in the CodeBlob's code or constants section 137 // Instruction types: memory (load), set (load address) 138 // Data: [] stored in 4 bytes of instruction 139 // [[L]l] a relative offset (see [About Offsets] below) 140 // In the case of section_word_type, the offset is relative to a section 141 // base address, and the section number (e.g., SECT_INSTS) is encoded 142 // into the low two bits of the offset L. 143 // 144 // relocInfo::external_word_type -- a fixed address in the runtime system 145 // Value: an address 146 // Instruction types: memory (load), set (load address) 147 // Data: [] stored in 4 bytes of instruction 148 // [n] the index of a "well-known" stub (usual case on RISC) 149 // [Ll] a 32-bit address 150 // 151 // relocInfo::runtime_call_type -- a fixed subroutine in the runtime system 152 // Value: an address 153 // Instruction types: PC-relative call (or a PC-relative branch) 154 // Data: [] stored in 4 bytes of instruction 155 // 156 // relocInfo::static_call_type -- a static call 157 // Value: an CodeBlob, a stub, or a fixup routine 158 // Instruction types: a call 159 // Data: [] 160 // The identity of the callee is extracted from debugging information. 161 // //%note reloc_3 162 // 163 // relocInfo::virtual_call_type -- a virtual call site (which includes an inline 164 // cache) 165 // Value: an CodeBlob, a stub, the interpreter, or a fixup routine 166 // Instruction types: a call, plus some associated set-oop instructions 167 // Data: [] the associated set-oops are adjacent to the call 168 // [n] n is a relative offset to the first set-oop 169 // [[N]n l] and l is a limit within which the set-oops occur 170 // [Nn Ll] both n and l may be 32 bits if necessary 171 // The identity of the callee is extracted from debugging information. 172 // 173 // relocInfo::opt_virtual_call_type -- a virtual call site that is statically bound 174 // 175 // Same info as a static_call_type. We use a special type, so the handling of 176 // virtuals and statics are separated. 177 // 178 // 179 // The offset n points to the first set-oop. (See [About Offsets] below.) 180 // In turn, the set-oop instruction specifies or contains an oop cell devoted 181 // exclusively to the IC call, which can be patched along with the call. 182 // 183 // The locations of any other set-oops are found by searching the relocation 184 // information starting at the first set-oop, and continuing until all 185 // relocations up through l have been inspected. The value l is another 186 // relative offset. (Both n and l are relative to the call's first byte.) 187 // 188 // The limit l of the search is exclusive. However, if it points within 189 // the call (e.g., offset zero), it is adjusted to point after the call and 190 // any associated machine-specific delay slot. 191 // 192 // Since the offsets could be as wide as 32-bits, these conventions 193 // put no restrictions whatever upon code reorganization. 194 // 195 // The compiler is responsible for ensuring that transition from a clean 196 // state to a monomorphic compiled state is MP-safe. This implies that 197 // the system must respond well to intermediate states where a random 198 // subset of the set-oops has been correctly from the clean state 199 // upon entry to the VEP of the compiled method. In the case of a 200 // machine (Intel) with a single set-oop instruction, the 32-bit 201 // immediate field must not straddle a unit of memory coherence. 202 // //%note reloc_3 203 // 204 // relocInfo::static_stub_type -- an extra stub for each static_call_type 205 // Value: none 206 // Instruction types: a virtual call: { set_oop; jump; } 207 // Data: [[N]n] the offset of the associated static_call reloc 208 // This stub becomes the target of a static call which must be upgraded 209 // to a virtual call (because the callee is interpreted). 210 // See [About Offsets] below. 211 // //%note reloc_2 212 // 213 // For example: 214 // 215 // INSTRUCTIONS RELOC: TYPE PREFIX DATA 216 // ------------ ---- ----------- 217 // sethi %hi(myObject), R oop_type [n(myObject)] 218 // ld [R+%lo(myObject)+fldOffset], R2 oop_type [n(myObject) fldOffset] 219 // add R2, 1, R2 220 // st R2, [R+%lo(myObject)+fldOffset] oop_type [n(myObject) fldOffset] 221 //%note reloc_1 222 // 223 // This uses 4 instruction words, 8 relocation halfwords, 224 // and an entry (which is sharable) in the CodeBlob's oop pool, 225 // for a total of 36 bytes. 226 // 227 // Note that the compiler is responsible for ensuring the "fldOffset" when 228 // added to "%lo(myObject)" does not overflow the immediate fields of the 229 // memory instructions. 230 // 231 // 232 // [About Offsets] Relative offsets are supplied to this module as 233 // positive byte offsets, but they may be internally stored scaled 234 // and/or negated, depending on what is most compact for the target 235 // system. Since the object pointed to by the offset typically 236 // precedes the relocation address, it is profitable to store 237 // these negative offsets as positive numbers, but this decision 238 // is internal to the relocation information abstractions. 239 // 240 241 class Relocation; 242 class CodeBuffer; 243 class CodeSection; 244 class RelocIterator; 245 246 class relocInfo VALUE_OBJ_CLASS_SPEC { 247 friend class RelocIterator; 248 public: 249 enum relocType { 250 none = 0, // Used when no relocation should be generated 251 oop_type = 1, // embedded oop 252 virtual_call_type = 2, // a standard inline cache call for a virtual send 253 opt_virtual_call_type = 3, // a virtual call that has been statically bound (i.e., no IC cache) 254 static_call_type = 4, // a static send 255 static_stub_type = 5, // stub-entry for static send (takes care of interpreter case) 256 runtime_call_type = 6, // call to fixed external routine 257 external_word_type = 7, // reference to fixed external address 258 internal_word_type = 8, // reference within the current code blob 259 section_word_type = 9, // internal, but a cross-section reference 260 poll_type = 10, // polling instruction for safepoints 261 poll_return_type = 11, // polling instruction for safepoints at return 262 metadata_type = 12, // metadata that used to be oops 263 trampoline_stub_type = 13, // stub-entry for trampoline 264 yet_unused_type_1 = 14, // Still unused 265 data_prefix_tag = 15, // tag for a prefix (carries data arguments) 266 type_mask = 15 // A mask which selects only the above values 267 }; 268 269 protected: 270 unsigned short _value; 271 272 enum RawBitsToken { RAW_BITS }; 273 relocInfo(relocType type, RawBitsToken ignore, int bits) 274 : _value((type << nontype_width) + bits) { } 275 276 relocInfo(relocType type, RawBitsToken ignore, int off, int f) 277 : _value((type << nontype_width) + (off / (unsigned)offset_unit) + (f << offset_width)) { } 278 279 public: 280 // constructor 281 relocInfo(relocType type, int offset, int format = 0) 282 #ifndef ASSERT 283 { 284 (*this) = relocInfo(type, RAW_BITS, offset, format); 285 } 286 #else 287 // Put a bunch of assertions out-of-line. 288 ; 289 #endif 290 291 #define APPLY_TO_RELOCATIONS(visitor)
292 visitor(oop)
293 visitor(metadata)
294 visitor(virtual_call)
295 visitor(opt_virtual_call)
296 visitor(static_call)
297 visitor(static_stub)
298 visitor(runtime_call)
299 visitor(external_word)
300 visitor(internal_word)
301 visitor(poll)
302 visitor(poll_return)
303 visitor(section_word)
304 visitor(trampoline_stub)
305 306 307 public: 308 enum { 309 value_width = sizeof(unsigned short) * BitsPerByte, 310 type_width = 4, // == log2(type_mask+1) 311 nontype_width = value_width - type_width, 312 datalen_width = nontype_width-1, 313 datalen_tag = 1 << datalen_width, // or-ed into _value 314 datalen_limit = 1 << datalen_width, 315 datalen_mask = (1 << datalen_width)-1 316 }; 317 318 // accessors 319 public: 320 relocType type() const { return (relocType)((unsigned)_value >> nontype_width); } 321 int format() const { return format_mask==0? 0: format_mask & 322 ((unsigned)_value >> offset_width); } 323 int addr_offset() const { assert(!is_prefix(), "must have offset"); 324 return (_value & offset_mask)offset_unit; } 325 326 protected: 327 const short data() const { assert(is_datalen(), "must have data"); 328 return (const short)(this + 1); } 329 int datalen() const { assert(is_datalen(), "must have data"); 330 return (_value & datalen_mask); } 331 int immediate() const { assert(is_immediate(), "must have immed"); 332 return (_value & datalen_mask); } 333 public: 334 static int addr_unit() { return offset_unit; } 335 static int offset_limit() { return (1 << offset_width) * offset_unit; } 336 337 void set_type(relocType type); 338 void set_format(int format); 339 340 void remove() { set_type(none); } 341 342 protected: 343 bool is_none() const { return type() == none; } 344 bool is_prefix() const { return type() == data_prefix_tag; } 345 bool is_datalen() const { assert(is_prefix(), "must be prefix"); 346 return (_value & datalen_tag) != 0; } 347 bool is_immediate() const { assert(is_prefix(), "must be prefix"); 348 return (_value & datalen_tag) == 0; } 349 350 public: 351 // Occasionally records of type relocInfo::none will appear in the stream. 352 // We do not bother to filter these out, but clients should ignore them. 353 // These records serve as "filler" in three ways: 354 // - to skip large spans of unrelocated code (this is rare) 355 // - to pad out the relocInfo array to the required oop alignment 356 // - to disable old relocation information which is no longer applicable 357 358 inline friend relocInfo filler_relocInfo(); 359 360 // Every non-prefix relocation may be preceded by at most one prefix, 361 // which supplies 1 or more halfwords of associated data. Conventionally, 362 // an int is represented by 0, 1, or 2 halfwords, depending on how 363 // many bits are required to represent the value. (In addition, 364 // if the sole halfword is a 10-bit unsigned number, it is made 365 // "immediate" in the prefix header word itself. This optimization 366 // is invisible outside this module.) 367 368 inline friend relocInfo prefix_relocInfo(int datalen); 369 370 protected: 371 // an immediate relocInfo optimizes a prefix with one 10-bit unsigned value 372 static relocInfo immediate_relocInfo(int data0) { 373 assert(fits_into_immediate(data0), "data0 in limits"); 374 return relocInfo(relocInfo::data_prefix_tag, RAW_BITS, data0); 375 } 376 static bool fits_into_immediate(int data0) { 377 return (data0 >= 0 && data0 < datalen_limit); 378 } 379 380 public: 381 // Support routines for compilers. 382 383 // This routine takes an infant relocInfo (unprefixed) and 384 // edits in its prefix, if any. It also updates dest.locs_end. 385 void initialize(CodeSection* dest, Relocation* reloc); 386 387 // This routine updates a prefix and returns the limit pointer. 388 // It tries to compress the prefix from 32 to 16 bits, and if 389 // successful returns a reduced "prefix_limit" pointer. 390 relocInfo* finish_prefix(short* prefix_limit); 391 392 // bit-packers for the data array: 393 394 // As it happens, the bytes within the shorts are ordered natively, 395 // but the shorts within the word are ordered big-endian. 396 // This is an arbitrary choice, made this way mainly to ease debugging. 397 static int data0_from_int(jint x) { return x >> value_width; } 398 static int data1_from_int(jint x) { return (short)x; } 399 static jint jint_from_data(short* data) { 400 return (data[0] << value_width) + (unsigned short)data[1]; 401 } 402 403 static jint short_data_at(int n, short* data, int datalen) { 404 return datalen > n ? data[n] : 0; 405 } 406 407 static jint jint_data_at(int n, short* data, int datalen) { 408 return datalen > n+1 ? jint_from_data(&data[n]) : short_data_at(n, data, datalen); 409 } 410 411 // Update methods for relocation information 412 // (since code is dynamically patched, we also need to dynamically update the relocation info) 413 // Both methods takes old_type, so it is able to performe sanity checks on the information removed. 414 static void change_reloc_info_for_address(RelocIterator itr, address pc, relocType old_type, relocType new_type); 415 static void remove_reloc_info_for_address(RelocIterator itr, address pc, relocType old_type); 416 417 // Machine dependent stuff 418 #ifdef TARGET_ARCH_x86 419 # include "relocInfo_x86.hpp" 420 #endif 421 #ifdef TARGET_ARCH_sparc 422 # include "relocInfo_sparc.hpp" 423 #endif 424 #ifdef TARGET_ARCH_zero 425 # include "relocInfo_zero.hpp" 426 #endif 427 #ifdef TARGET_ARCH_arm 428 # include "relocInfo_arm.hpp" 429 #endif 430 #ifdef TARGET_ARCH_ppc 431 # include "relocInfo_ppc.hpp" 432 #endif 433 #ifdef TARGET_ARCH_aarch64 434 # include "relocInfo_aarch64.hpp" 435 #endif 436 437 protected: 438 // Derived constant, based on format_width which is PD: 439 enum { 440 offset_width = nontype_width - format_width, 441 offset_mask = (1<<offset_width) - 1, 442 format_mask = (1<<format_width) - 1 443 }; 444 public: 445 enum { 446 // Conservatively large estimate of maximum length (in shorts) 447 // of any relocation record. 448 // Extended format is length prefix, data words, and tag/offset suffix. 449 length_limit = 1 + 1 + (3*BytesPerWord/BytesPerShort) + 1, 450 have_format = format_width > 0 451 }; 452 }; 453 454 #define FORWARD_DECLARE_EACH_CLASS(name)
455 class name##_Relocation; 456 APPLY_TO_RELOCATIONS(FORWARD_DECLARE_EACH_CLASS) 457 #undef FORWARD_DECLARE_EACH_CLASS 458 459 460 461 inline relocInfo filler_relocInfo() { 462 return relocInfo(relocInfo::none, relocInfo::offset_limit() - relocInfo::offset_unit); 463 } 464 465 inline relocInfo prefix_relocInfo(int datalen = 0) { 466 assert(relocInfo::fits_into_immediate(datalen), "datalen in limits"); 467 return relocInfo(relocInfo::data_prefix_tag, relocInfo::RAW_BITS, relocInfo::datalen_tag | datalen); 468 } 469 470 471 // Holder for flyweight relocation objects. 472 // Although the flyweight subclasses are of varying sizes, 473 // the holder is "one size fits all". 474 class RelocationHolder VALUE_OBJ_CLASS_SPEC { 475 friend class Relocation; 476 friend class CodeSection; 477 478 private: 479 // this preallocated memory must accommodate all subclasses of Relocation 480 // (this number is assertion-checked in Relocation::operator new) 481 enum { _relocbuf_size = 5 }; 482 void _relocbuf[ _relocbuf_size ]; 483 484 public: 485 Relocation reloc() const { return (Relocation*) &_relocbuf[0]; } 486 inline relocInfo::relocType type() const; 487 488 // Add a constant offset to a relocation. Helper for class Address. 489 RelocationHolder plus(int offset) const; 490 491 inline RelocationHolder(); // initializes type to none 492 493 inline RelocationHolder(Relocation* r); // make a copy 494 495 static const RelocationHolder none; 496 }; 497 498 // A RelocIterator iterates through the relocation information of a CodeBlob. 499 // It is a variable BoundRelocation which is able to take on successive 500 // values as it is advanced through a code stream. 501 // Usage: 502 // RelocIterator iter(nm); 503 // while (iter.next()) { 504 // iter.reloc()->some_operation(); 505 // } 506 // or: 507 // RelocIterator iter(nm); 508 // while (iter.next()) { 509 // switch (iter.type()) { 510 // case relocInfo::oop_type : 511 // case relocInfo::ic_type : 512 // case relocInfo::prim_type : 513 // case relocInfo::uncommon_type : 514 // case relocInfo::runtime_call_type : 515 // case relocInfo::internal_word_type: 516 // case relocInfo::external_word_type: 517 // ... 518 // } 519 // } 520 521 class RelocIterator : public StackObj { 522 enum { SECT_LIMIT = 3 }; // must be equal to CodeBuffer::SECT_LIMIT, checked in ctor 523 friend class Relocation; 524 friend class relocInfo; // for change_reloc_info_for_address only 525 typedef relocInfo::relocType relocType; 526 527 private: 528 address _limit; // stop producing relocations after this _addr 529 relocInfo* _current; // the current relocation information 530 relocInfo* _end; // end marker; we're done iterating when _current == _end 531 nmethod* _code; // compiled method containing _addr 532 address _addr; // instruction to which the relocation applies 533 short _databuf; // spare buffer for compressed data 534 short* _data; // pointer to the relocation's data 535 short _datalen; // number of halfwords in _data 536 char _format; // position within the instruction 537 538 // Base addresses needed to compute targets of section_word_type relocs. 539 address _section_start[SECT_LIMIT]; 540 address _section_end [SECT_LIMIT]; 541 542 void set_has_current(bool b) { 543 _datalen = !b ? -1 : 0; 544 debug_only(_data = NULL); 545 } 546 void set_current(relocInfo& ri) { 547 _current = &ri; 548 set_has_current(true); 549 } 550 551 RelocationHolder _rh; // where the current relocation is allocated 552 553 relocInfo* current() const { assert(has_current(), "must have current"); 554 return _current; } 555 556 void set_limits(address begin, address limit); 557 558 void advance_over_prefix(); // helper method 559 560 void initialize_misc(); 561 562 void initialize(nmethod* nm, address begin, address limit); 563 564 RelocIterator() { initialize_misc(); } 565 566 public: 567 // constructor 568 RelocIterator(nmethod* nm, address begin = NULL, address limit = NULL); 569 RelocIterator(CodeSection* cb, address begin = NULL, address limit = NULL); 570 571 // get next reloc info, return !eos 572 bool next() { 573 _current++; 574 assert(_current <= _end, "must not overrun relocInfo"); 575 if (_current == _end) { 576 set_has_current(false); 577 return false; 578 } 579 set_has_current(true); 580 581 if (_current->is_prefix()) { 582 advance_over_prefix(); 583 assert(!current()->is_prefix(), "only one prefix at a time"); 584 } 585 586 _addr += _current->addr_offset(); 587 588 if (_limit != NULL && _addr >= _limit) { 589 set_has_current(false); 590 return false; 591 } 592 593 if (relocInfo::have_format) _format = current()->format(); 594 return true; 595 } 596 597 // accessors 598 address limit() const { return _limit; } 599 void set_limit(address x); 600 relocType type() const { return current()->type(); } 601 int format() const { return (relocInfo::have_format) ? current()->format() : 0; } 602 address addr() const { return _addr; } 603 nmethod* code() const { return _code; } 604 short* data() const { return _data; } 605 int datalen() const { return _datalen; } 606 bool has_current() const { return _datalen >= 0; } 607 608 void set_addr(address addr) { _addr = addr; } 609 bool addr_in_const() const; 610 611 address section_start(int n) const { 612 assert(_section_start[n], "must be initialized"); 613 return _section_start[n]; 614 } 615 address section_end(int n) const { 616 assert(_section_end[n], "must be initialized"); 617 return _section_end[n]; 618 } 619 620 // The address points to the affected displacement part of the instruction. 621 // For RISC, this is just the whole instruction. 622 // For Intel, this is an unaligned 32-bit word. 623 624 // type-specific relocation accessors: oop_Relocation* oop_reloc(), etc. 625 #define EACH_TYPE(name)
626 inline name##_Relocation* name##_reloc(); 627 APPLY_TO_RELOCATIONS(EACH_TYPE) 628 #undef EACH_TYPE 629 // generic relocation accessor; switches on type to call the above 630 Relocation* reloc(); 631 632 // CodeBlob's have relocation indexes for faster random access: 633 static int locs_and_index_size(int code_size, int locs_size); 634 // Store an index into [dest_start+dest_count..dest_end). 635 // At dest_start[0..dest_count] is the actual relocation information. 636 // Everything else up to dest_end is free space for the index. 637 static void create_index(relocInfo* dest_begin, int dest_count, relocInfo* dest_end); 638 639 #ifndef PRODUCT 640 public: 641 void print(); 642 void print_current(); 643 #endif 644 }; 645 646 647 // A Relocation is a flyweight object allocated within a RelocationHolder. 648 // It represents the relocation data of relocation record. 649 // So, the RelocIterator unpacks relocInfos into Relocations. 650 651 class Relocation VALUE_OBJ_CLASS_SPEC { 652 friend class RelocationHolder; 653 friend class RelocIterator; 654 655 private: 656 static void guarantee_size(); 657 658 // When a relocation has been created by a RelocIterator, 659 // this field is non-null. It allows the relocation to know 660 // its context, such as the address to which it applies. 661 RelocIterator* _binding; 662 663 protected: 664 RelocIterator* binding() const { 665 assert(_binding != NULL, "must be bound"); 666 return _binding; 667 } 668 void set_binding(RelocIterator* b) { 669 assert(_binding == NULL, "must be unbound"); 670 _binding = b; 671 assert(_binding != NULL, "must now be bound"); 672 } 673 674 Relocation() { 675 _binding = NULL; 676 } 677 678 static RelocationHolder newHolder() { 679 return RelocationHolder(); 680 } 681 682 public: 683 void* operator new(size_t size, const RelocationHolder& holder) throw() { 684 if (size > sizeof(holder._relocbuf)) guarantee_size(); 685 assert((void* const )holder.reloc() == &holder._relocbuf[0], "ptrs must agree"); 686 return holder.reloc(); 687 } 688 689 // make a generic relocation for a given type (if possible) 690 static RelocationHolder spec_simple(relocInfo::relocType rtype); 691 692 // here is the type-specific hook which writes relocation data: 693 virtual void pack_data_to(CodeSection dest) { } 694 695 // here is the type-specific hook which reads (unpacks) relocation data: 696 virtual void unpack_data() { 697 assert(datalen()==0 || type()==relocInfo::none, "no data here"); 698 } 699 700 static bool is_reloc_index(intptr_t index) { 701 return 0 < index && index < os::vm_page_size(); 702 } 703 704 protected: 705 // Helper functions for pack_data_to() and unpack_data(). 706 707 // Most of the compression logic is confined here. 708 // (The "immediate data" mechanism of relocInfo works independently 709 // of this stuff, and acts to further compress most 1-word data prefixes.) 710 711 // A variable-width int is encoded as a short if it will fit in 16 bits. 712 // The decoder looks at datalen to decide whether to unpack short or jint. 713 // Most relocation records are quite simple, containing at most two ints. 714 715 static bool is_short(jint x) { return x == (short)x; } 716 static short* add_short(short* p, int x) { p++ = x; return p; } 717 static short* add_jint (short* p, jint x) { 718 p++ = relocInfo::data0_from_int(x); p++ = relocInfo::data1_from_int(x); 719 return p; 720 } 721 static short add_var_int(short p, jint x) { // add a variable-width int 722 if (is_short(x)) p = add_short(p, x); 723 else p = add_jint (p, x); 724 return p; 725 } 726 727 static short* pack_1_int_to(short* p, jint x0) { 728 // Format is one of: [] [x] [Xx] 729 if (x0 != 0) p = add_var_int(p, x0); 730 return p; 731 } 732 int unpack_1_int() { 733 assert(datalen() <= 2, "too much data"); 734 return relocInfo::jint_data_at(0, data(), datalen()); 735 } 736 737 // With two ints, the short form is used only if both ints are short. 738 short* pack_2_ints_to(short* p, jint x0, jint x1) { 739 // Format is one of: [] [x y?] [Xx Y?y] 740 if (x0 == 0 && x1 == 0) { 741 // no halfwords needed to store zeroes 742 } else if (is_short(x0) && is_short(x1)) { 743 // 1-2 halfwords needed to store shorts 744 p = add_short(p, x0); if (x1!=0) p = add_short(p, x1); 745 } else { 746 // 3-4 halfwords needed to store jints 747 p = add_jint(p, x0); p = add_var_int(p, x1); 748 } 749 return p; 750 } 751 void unpack_2_ints(jint& x0, jint& x1) { 752 int dlen = datalen(); 753 short* dp = data(); 754 if (dlen <= 2) { 755 x0 = relocInfo::short_data_at(0, dp, dlen); 756 x1 = relocInfo::short_data_at(1, dp, dlen); 757 } else { 758 assert(dlen <= 4, "too much data"); 759 x0 = relocInfo::jint_data_at(0, dp, dlen); 760 x1 = relocInfo::jint_data_at(2, dp, dlen); 761 } 762 } 763 764 protected: 765 // platform-dependent utilities for decoding and patching instructions 766 void pd_set_data_value (address x, intptr_t off, bool verify_only = false); // a set or mem-ref 767 void pd_verify_data_value (address x, intptr_t off) { pd_set_data_value(x, off, true); } 768 address pd_call_destination (address orig_addr = NULL); 769 void pd_set_call_destination (address x); 770 771 // this extracts the address of an address in the code stream instead of the reloc data 772 address* pd_address_in_code (); 773 774 // this extracts an address from the code stream instead of the reloc data 775 address pd_get_address_from_code (); 776 777 // these convert from byte offsets, to scaled offsets, to addresses 778 static jint scaled_offset(address x, address base) { 779 int byte_offset = x - base; 780 int offset = -byte_offset / relocInfo::addr_unit(); 781 assert(address_from_scaled_offset(offset, base) == x, "just checkin'"); 782 return offset; 783 } 784 static jint scaled_offset_null_special(address x, address base) { 785 // Some relocations treat offset=0 as meaning NULL. 786 // Handle this extra convention carefully. 787 if (x == NULL) return 0; 788 assert(x != base, "offset must not be zero"); 789 return scaled_offset(x, base); 790 } 791 static address address_from_scaled_offset(jint offset, address base) { 792 int byte_offset = -( offset * relocInfo::addr_unit() ); 793 return base + byte_offset; 794 } 795 796 // these convert between indexes and addresses in the runtime system 797 static int32_t runtime_address_to_index(address runtime_address); 798 static address index_to_runtime_address(int32_t index); 799 800 // helpers for mapping between old and new addresses after a move or resize 801 address old_addr_for(address newa, const CodeBuffer* src, CodeBuffer* dest); 802 address new_addr_for(address olda, const CodeBuffer* src, CodeBuffer* dest); 803 void normalize_address(address& addr, const CodeSection* dest, bool allow_other_sections = false); 804 805 public: 806 // accessors which only make sense for a bound Relocation 807 address addr() const { return binding()->addr(); } 808 nmethod code() const { return binding()->code(); } 809 bool addr_in_const() const { return binding()->addr_in_const(); } 810 protected: 811 short* data() const { return binding()->data(); } 812 int datalen() const { return binding()->datalen(); } 813 int format() const { return binding()->format(); } 814 815 public: 816 virtual relocInfo::relocType type() { return relocInfo::none; } 817 818 // is it a call instruction? 819 virtual bool is_call() { return false; } 820 821 // is it a data movement instruction? 822 virtual bool is_data() { return false; } 823 824 // some relocations can compute their own values 825 virtual address value(); 826 827 // all relocations are able to reassert their values 828 virtual void set_value(address x); 829 830 virtual void clear_inline_cache() { } 831 832 // This method assumes that all virtual/static (inline) caches are cleared (since for static_call_type and 833 // ic_call_type is not always posisition dependent (depending on the state of the cache)). However, this is 834 // probably a reasonable assumption, since empty caches simplifies code reloacation. 835 virtual void fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest) { } 836 837 void print(); 838 }; 839 840 841 // certain inlines must be deferred until class Relocation is defined: 842 843 inline RelocationHolder::RelocationHolder() { 844 // initialize the vtbl, just to keep things type-safe 845 new(this) Relocation(); 846 } 847 848 849 inline RelocationHolder::RelocationHolder(Relocation r) { 850 // wordwise copy from r (ok if it copies garbage after r) 851 for (int i = 0; i < _relocbuf_size; i++) { 852 _relocbuf[i] = ((void**)r)[i]; 853 } 854 } 855 856 857 relocInfo::relocType RelocationHolder::type() const { 858 return reloc()->type(); 859 } 860 861 // A DataRelocation always points at a memory or load-constant instruction.. 862 // It is absolute on most machines, and the constant is split on RISCs. 863 // The specific subtypes are oop, external_word, and internal_word. 864 // By convention, the "value" does not include a separately reckoned "offset". 865 class DataRelocation : public Relocation { 866 public: 867 bool is_data() { return true; } 868 869 // both target and offset must be computed somehow from relocation data 870 virtual int offset() { return 0; } 871 address value() = 0; 872 void set_value(address x) { set_value(x, offset()); } 873 void set_value(address x, intptr_t o) { 874 if (addr_in_const()) 875 (address)addr() = x; 876 else 877 pd_set_data_value(x, o); 878 } 879 void verify_value(address x) { 880 if (addr_in_const()) 881 assert((address)addr() == x, "must agree"); 882 else 883 pd_verify_data_value(x, offset()); 884 } 885 886 // The "o" (displacement) argument is relevant only to split relocations 887 // on RISC machines. In some CPUs (SPARC), the set-hi and set-lo ins'ns 888 // can encode more than 32 bits between them. This allows compilers to 889 // share set-hi instructions between addresses that differ by a small 890 // offset (e.g., different static variables in the same class). 891 // On such machines, the "x" argument to set_value on all set-lo 892 // instructions must be the same as the "x" argument for the 893 // corresponding set-hi instructions. The "o" arguments for the 894 // set-hi instructions are ignored, and must not affect the high-half 895 // immediate constant. The "o" arguments for the set-lo instructions are 896 // added into the low-half immediate constant, and must not overflow it. 897 }; 898 899 // A CallRelocation always points at a call instruction. 900 // It is PC-relative on most machines. 901 class CallRelocation : public Relocation { 902 public: 903 bool is_call() { return true; } 904 905 address destination() { return pd_call_destination(); } 906 void set_destination(address x); // pd_set_call_destination 907 908 void fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest); 909 address value() { return destination(); } 910 void set_value(address x) { set_destination(x); } 911 }; 912 913 class oop_Relocation : public DataRelocation { 914 relocInfo::relocType type() { return relocInfo::oop_type; } 915 916 public: 917 // encode in one of these formats: [] [n] [n l] [Nn l] [Nn Ll] 918 // an oop in the CodeBlob's oop pool 919 static RelocationHolder spec(int oop_index, int offset = 0) { 920 assert(oop_index > 0, "must be a pool-resident oop"); 921 RelocationHolder rh = newHolder(); 922 new(rh) oop_Relocation(oop_index, offset); 923 return rh; 924 } 925 // an oop in the instruction stream 926 static RelocationHolder spec_for_immediate() { 927 const int oop_index = 0; 928 const int offset = 0; // if you want an offset, use the oop pool 929 RelocationHolder rh = newHolder(); 930 new(rh) oop_Relocation(oop_index, offset); 931 return rh; 932 } 933 934 private: 935 jint _oop_index; // if > 0, index into CodeBlob::oop_at 936 jint _offset; // byte offset to apply to the oop itself 937 938 oop_Relocation(int oop_index, int offset) { 939 _oop_index = oop_index; _offset = offset; 940 } 941 942 friend class RelocIterator; 943 oop_Relocation() { } 944 945 public: 946 int oop_index() { return _oop_index; } 947 int offset() { return _offset; } 948 949 // data is packed in "2_ints" format: [i o] or [Ii Oo] 950 void pack_data_to(CodeSection* dest); 951 void unpack_data(); 952 953 void fix_oop_relocation(); // reasserts oop value 954 955 void verify_oop_relocation(); 956 957 address value() { return (address) oop_addr(); } 958 959 bool oop_is_immediate() { return oop_index() == 0; } 960 961 oop oop_addr(); // addr or &pool[jint_data] 962 oop oop_value(); // oop_addr 963 // Note: oop_value transparently converts Universe::non_oop_word to NULL. 964 }; 965 966 967 // copy of oop_Relocation for now but may delete stuff in both/either 968 class metadata_Relocation : public DataRelocation { 969 relocInfo::relocType type() { return relocInfo::metadata_type; } 970 971 public: 972 // encode in one of these formats: [] [n] [n l] [Nn l] [Nn Ll] 973 // an metadata in the CodeBlob's metadata pool 974 static RelocationHolder spec(int metadata_index, int offset = 0) { 975 assert(metadata_index > 0, "must be a pool-resident metadata"); 976 RelocationHolder rh = newHolder(); 977 new(rh) metadata_Relocation(metadata_index, offset); 978 return rh; 979 } 980 // an metadata in the instruction stream 981 static RelocationHolder spec_for_immediate() { 982 const int metadata_index = 0; 983 const int offset = 0; // if you want an offset, use the metadata pool 984 RelocationHolder rh = newHolder(); 985 new(rh) metadata_Relocation(metadata_index, offset); 986 return rh; 987 } 988 989 private: 990 jint _metadata_index; // if > 0, index into nmethod::metadata_at 991 jint _offset; // byte offset to apply to the metadata itself 992 993 metadata_Relocation(int metadata_index, int offset) { 994 _metadata_index = metadata_index; _offset = offset; 995 } 996 997 friend class RelocIterator; 998 metadata_Relocation() { } 999 1000 // Fixes a Metadata pointer in the code. Most platforms embeds the 1001 // Metadata pointer in the code at compile time so this is empty 1002 // for them. 1003 void pd_fix_value(address x); 1004 1005 public: 1006 int metadata_index() { return _metadata_index; } 1007 int offset() { return _offset; } 1008 1009 // data is packed in "2_ints" format: [i o] or [Ii Oo] 1010 void pack_data_to(CodeSection dest); 1011 void unpack_data(); 1012 1013 void fix_metadata_relocation(); // reasserts metadata value 1014 1015 void verify_metadata_relocation(); 1016 1017 address value() { return (address) metadata_addr(); } 1018 1019 bool metadata_is_immediate() { return metadata_index() == 0; } 1020 1021 Metadata* metadata_addr(); // addr or &pool[jint_data] 1022 Metadata* metadata_value(); // metadata_addr 1023 // Note: metadata_value transparently converts Universe::non_metadata_word to NULL. 1024 }; 1025 1026 1027 class virtual_call_Relocation : public CallRelocation { 1028 relocInfo::relocType type() { return relocInfo::virtual_call_type; } 1029 1030 public: 1031 // "cached_value" points to the first associated set-oop. 1032 // The oop_limit helps find the last associated set-oop. 1033 // (See comments at the top of this file.) 1034 static RelocationHolder spec(address cached_value) { 1035 RelocationHolder rh = newHolder(); 1036 new(rh) virtual_call_Relocation(cached_value); 1037 return rh; 1038 } 1039 1040 virtual_call_Relocation(address cached_value) { 1041 _cached_value = cached_value; 1042 assert(cached_value != NULL, "first oop address must be specified"); 1043 } 1044 1045 private: 1046 address _cached_value; // location of set-value instruction 1047 1048 friend class RelocIterator; 1049 virtual_call_Relocation() { } 1050 1051 1052 public: 1053 address cached_value(); 1054 1055 // data is packed as scaled offsets in "2_ints" format: [f l] or [Ff Ll] 1056 // oop_limit is set to 0 if the limit falls somewhere within the call. 1057 // When unpacking, a zero oop_limit is taken to refer to the end of the call. 1058 // (This has the effect of bringing in the call's delay slot on SPARC.) 1059 void pack_data_to(CodeSection dest); 1060 void unpack_data(); 1061 1062 void clear_inline_cache(); 1063 }; 1064 1065 1066 class opt_virtual_call_Relocation : public CallRelocation { 1067 relocInfo::relocType type() { return relocInfo::opt_virtual_call_type; } 1068 1069 public: 1070 static RelocationHolder spec() { 1071 RelocationHolder rh = newHolder(); 1072 new(rh) opt_virtual_call_Relocation(); 1073 return rh; 1074 } 1075 1076 private: 1077 friend class RelocIterator; 1078 opt_virtual_call_Relocation() { } 1079 1080 public: 1081 void clear_inline_cache(); 1082 1083 // find the matching static_stub 1084 address static_stub(); 1085 }; 1086 1087 1088 class static_call_Relocation : public CallRelocation { 1089 relocInfo::relocType type() { return relocInfo::static_call_type; } 1090 1091 public: 1092 static RelocationHolder spec() { 1093 RelocationHolder rh = newHolder(); 1094 new(rh) static_call_Relocation(); 1095 return rh; 1096 } 1097 1098 private: 1099 friend class RelocIterator; 1100 static_call_Relocation() { } 1101 1102 public: 1103 void clear_inline_cache(); 1104 1105 // find the matching static_stub 1106 address static_stub(); 1107 }; 1108 1109 class static_stub_Relocation : public Relocation { 1110 relocInfo::relocType type() { return relocInfo::static_stub_type; } 1111 1112 public: 1113 static RelocationHolder spec(address static_call) { 1114 RelocationHolder rh = newHolder(); 1115 new(rh) static_stub_Relocation(static_call); 1116 return rh; 1117 } 1118 1119 private: 1120 address _static_call; // location of corresponding static_call 1121 1122 static_stub_Relocation(address static_call) { 1123 _static_call = static_call; 1124 } 1125 1126 friend class RelocIterator; 1127 static_stub_Relocation() { } 1128 1129 public: 1130 void clear_inline_cache(); 1131 1132 address static_call() { return _static_call; } 1133 1134 // data is packed as a scaled offset in "1_int" format: [c] or [Cc] 1135 void pack_data_to(CodeSection* dest); 1136 void unpack_data(); 1137 }; 1138 1139 class runtime_call_Relocation : public CallRelocation { 1140 relocInfo::relocType type() { return relocInfo::runtime_call_type; } 1141 1142 public: 1143 static RelocationHolder spec() { 1144 RelocationHolder rh = newHolder(); 1145 new(rh) runtime_call_Relocation(); 1146 return rh; 1147 } 1148 1149 private: 1150 friend class RelocIterator; 1151 runtime_call_Relocation() { } 1152 1153 public: 1154 }; 1155 1156 // Trampoline Relocations. 1157 // A trampoline allows to encode a small branch in the code, even if there 1158 // is the chance that this branch can not reach all possible code locations. 1159 // If the relocation finds that a branch is too far for the instruction 1160 // in the code, it can patch it to jump to the trampoline where is 1161 // sufficient space for a far branch. Needed on PPC. 1162 class trampoline_stub_Relocation : public Relocation { 1163 relocInfo::relocType type() { return relocInfo::trampoline_stub_type; } 1164 1165 public: 1166 static RelocationHolder spec(address static_call) { 1167 RelocationHolder rh = newHolder(); 1168 return (new (rh) trampoline_stub_Relocation(static_call)); 1169 } 1170 1171 private: 1172 address _owner; // Address of the NativeCall that owns the trampoline. 1173 1174 trampoline_stub_Relocation(address owner) { 1175 _owner = owner; 1176 } 1177 1178 friend class RelocIterator; 1179 trampoline_stub_Relocation() { } 1180 1181 public: 1182 1183 // Return the address of the NativeCall that owns the trampoline. 1184 address owner() { return _owner; } 1185 1186 void pack_data_to(CodeSection * dest); 1187 void unpack_data(); 1188 1189 // Find the trampoline stub for a call. 1190 static address get_trampoline_for(address call, nmethod* code); 1191 }; 1192 1193 class external_word_Relocation : public DataRelocation { 1194 relocInfo::relocType type() { return relocInfo::external_word_type; } 1195 1196 public: 1197 static RelocationHolder spec(address target) { 1198 assert(target != NULL, "must not be null"); 1199 RelocationHolder rh = newHolder(); 1200 new(rh) external_word_Relocation(target); 1201 return rh; 1202 } 1203 1204 // Use this one where all 32/64 bits of the target live in the code stream. 1205 // The target must be an intptr_t, and must be absolute (not relative). 1206 static RelocationHolder spec_for_immediate() { 1207 RelocationHolder rh = newHolder(); 1208 new(rh) external_word_Relocation(NULL); 1209 return rh; 1210 } 1211 1212 // Some address looking values aren't safe to treat as relocations 1213 // and should just be treated as constants. 1214 static bool can_be_relocated(address target) { 1215 return target != NULL && !is_reloc_index((intptr_t)target); 1216 } 1217 1218 private: 1219 address _target; // address in runtime 1220 1221 external_word_Relocation(address target) { 1222 _target = target; 1223 } 1224 1225 friend class RelocIterator; 1226 external_word_Relocation() { } 1227 1228 public: 1229 // data is packed as a well-known address in "1_int" format: [a] or [Aa] 1230 // The function runtime_address_to_index is used to turn full addresses 1231 // to short indexes, if they are pre-registered by the stub mechanism. 1232 // If the "a" value is 0 (i.e., _target is NULL), the address is stored 1233 // in the code stream. See external_word_Relocation::target(). 1234 void pack_data_to(CodeSection* dest); 1235 void unpack_data(); 1236 1237 void fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest); 1238 address target(); // if _target==NULL, fetch addr from code stream 1239 address value() { return target(); } 1240 }; 1241 1242 class internal_word_Relocation : public DataRelocation { 1243 relocInfo::relocType type() { return relocInfo::internal_word_type; } 1244 1245 public: 1246 static RelocationHolder spec(address target) { 1247 assert(target != NULL, "must not be null"); 1248 RelocationHolder rh = newHolder(); 1249 new(rh) internal_word_Relocation(target); 1250 return rh; 1251 } 1252 1253 // use this one where all the bits of the target can fit in the code stream: 1254 static RelocationHolder spec_for_immediate() { 1255 RelocationHolder rh = newHolder(); 1256 new(rh) internal_word_Relocation(NULL); 1257 return rh; 1258 } 1259 1260 internal_word_Relocation(address target) { 1261 _target = target; 1262 _section = -1; // self-relative 1263 } 1264 1265 protected: 1266 address _target; // address in CodeBlob 1267 int _section; // section providing base address, if any 1268 1269 friend class RelocIterator; 1270 internal_word_Relocation() { } 1271 1272 // bit-width of LSB field in packed offset, if section >= 0 1273 enum { section_width = 2 }; // must equal CodeBuffer::sect_bits 1274 1275 public: 1276 // data is packed as a scaled offset in "1_int" format: [o] or [Oo] 1277 // If the "o" value is 0 (i.e., _target is NULL), the offset is stored 1278 // in the code stream. See internal_word_Relocation::target(). 1279 // If _section is not -1, it is appended to the low bits of the offset. 1280 void pack_data_to(CodeSection* dest); 1281 void unpack_data(); 1282 1283 void fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest); 1284 address target(); // if _target==NULL, fetch addr from code stream 1285 int section() { return _section; } 1286 address value() { return target(); } 1287 }; 1288 1289 class section_word_Relocation : public internal_word_Relocation { 1290 relocInfo::relocType type() { return relocInfo::section_word_type; } 1291 1292 public: 1293 static RelocationHolder spec(address target, int section) { 1294 RelocationHolder rh = newHolder(); 1295 new(rh) section_word_Relocation(target, section); 1296 return rh; 1297 } 1298 1299 section_word_Relocation(address target, int section) { 1300 assert(target != NULL, "must not be null"); 1301 assert(section >= 0, "must be a valid section"); 1302 _target = target; 1303 _section = section; 1304 } 1305 1306 //void pack_data_to -- inherited 1307 void unpack_data(); 1308 1309 private: 1310 friend class RelocIterator; 1311 section_word_Relocation() { } 1312 }; 1313 1314 1315 class poll_Relocation : public Relocation { 1316 bool is_data() { return true; } 1317 relocInfo::relocType type() { return relocInfo::poll_type; } 1318 void fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest); 1319 }; 1320 1321 class poll_return_Relocation : public Relocation { 1322 bool is_data() { return true; } 1323 relocInfo::relocType type() { return relocInfo::poll_return_type; } 1324 void fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest); 1325 }; 1326 1327 // We know all the xxx_Relocation classes, so now we can define these: 1328 #define EACH_CASE(name)
1329 inline name##_Relocation* RelocIterator::name##_reloc() {
1330 assert(type() == relocInfo::name##_type, "type must agree");
1331 /* The purpose of the placed "new" is to re-use the same /
1332 / stack storage for each new iteration. /
1333 name##_Relocation r = new(_rh) name##_Relocation();
1334 r->set_binding(this);
1335 r->name##_Relocation::unpack_data();
1336 return r;
1337 } 1338 APPLY_TO_RELOCATIONS(EACH_CASE); 1339 #undef EACH_CASE 1340 1341 inline RelocIterator::RelocIterator(nmethod* nm, address begin, address limit) { 1342 initialize(nm, begin, limit); 1343 } 1344 1345 #endif // SHARE_VM_CODE_RELOCINFO_HPP