1 /*
2 * Copyright (c) 1997, 2012, 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
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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).
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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_<arch>.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_<arch>.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
434
435 protected:
436 // Derived constant, based on format_width which is PD:
437 enum {
438 offset_width = nontype_width - format_width,
439 offset_mask = (1<<offset_width) - 1,
440 format_mask = (1<<format_width) - 1
441 };
442 public:
443 enum {
444 // Conservatively large estimate of maximum length (in shorts)
445 // of any relocation record.
446 // Extended format is length prefix, data words, and tag/offset suffix.
447 length_limit = 1 + 1 + (3*BytesPerWord/BytesPerShort) + 1,
448 have_format = format_width > 0
449 };
450 };
451
452 #define FORWARD_DECLARE_EACH_CLASS(name) \
453 class name##_Relocation;
454 APPLY_TO_RELOCATIONS(FORWARD_DECLARE_EACH_CLASS)
455 #undef FORWARD_DECLARE_EACH_CLASS
456
457
458
459 inline relocInfo filler_relocInfo() {
460 return relocInfo(relocInfo::none, relocInfo::offset_limit() - relocInfo::offset_unit);
461 }
462
463 inline relocInfo prefix_relocInfo(int datalen = 0) {
464 assert(relocInfo::fits_into_immediate(datalen), "datalen in limits");
465 return relocInfo(relocInfo::data_prefix_tag, relocInfo::RAW_BITS, relocInfo::datalen_tag | datalen);
466 }
467
468
469 // Holder for flyweight relocation objects.
470 // Although the flyweight subclasses are of varying sizes,
471 // the holder is "one size fits all".
472 class RelocationHolder VALUE_OBJ_CLASS_SPEC {
473 friend class Relocation;
474 friend class CodeSection;
475
476 private:
477 // this preallocated memory must accommodate all subclasses of Relocation
478 // (this number is assertion-checked in Relocation::operator new)
479 enum { _relocbuf_size = 5 };
480 void* _relocbuf[ _relocbuf_size ];
481
482 public:
483 Relocation* reloc() const { return (Relocation*) &_relocbuf[0]; }
484 inline relocInfo::relocType type() const;
485
486 // Add a constant offset to a relocation. Helper for class Address.
487 RelocationHolder plus(int offset) const;
488
489 inline RelocationHolder(); // initializes type to none
490
491 inline RelocationHolder(Relocation* r); // make a copy
492
493 static const RelocationHolder none;
494 };
495
496 // A RelocIterator iterates through the relocation information of a CodeBlob.
497 // It is a variable BoundRelocation which is able to take on successive
498 // values as it is advanced through a code stream.
499 // Usage:
500 // RelocIterator iter(nm);
501 // while (iter.next()) {
502 // iter.reloc()->some_operation();
503 // }
504 // or:
505 // RelocIterator iter(nm);
506 // while (iter.next()) {
507 // switch (iter.type()) {
508 // case relocInfo::oop_type :
509 // case relocInfo::ic_type :
510 // case relocInfo::prim_type :
511 // case relocInfo::uncommon_type :
512 // case relocInfo::runtime_call_type :
513 // case relocInfo::internal_word_type:
514 // case relocInfo::external_word_type:
515 // ...
516 // }
517 // }
518
519 class RelocIterator : public StackObj {
520 enum { SECT_LIMIT = 3 }; // must be equal to CodeBuffer::SECT_LIMIT, checked in ctor
521 friend class Relocation;
522 friend class relocInfo; // for change_reloc_info_for_address only
523 typedef relocInfo::relocType relocType;
524
525 private:
526 address _limit; // stop producing relocations after this _addr
527 relocInfo* _current; // the current relocation information
528 relocInfo* _end; // end marker; we're done iterating when _current == _end
529 nmethod* _code; // compiled method containing _addr
530 address _addr; // instruction to which the relocation applies
531 short _databuf; // spare buffer for compressed data
532 short* _data; // pointer to the relocation's data
533 short _datalen; // number of halfwords in _data
534 char _format; // position within the instruction
535
536 // Base addresses needed to compute targets of section_word_type relocs.
537 address _section_start[SECT_LIMIT];
538 address _section_end [SECT_LIMIT];
539
540 void set_has_current(bool b) {
541 _datalen = !b ? -1 : 0;
542 debug_only(_data = NULL);
543 }
544 void set_current(relocInfo& ri) {
545 _current = &ri;
546 set_has_current(true);
547 }
548
549 RelocationHolder _rh; // where the current relocation is allocated
550
551 relocInfo* current() const { assert(has_current(), "must have current");
552 return _current; }
553
554 void set_limits(address begin, address limit);
555
556 void advance_over_prefix(); // helper method
557
558 void initialize_misc();
559
560 void initialize(nmethod* nm, address begin, address limit);
561
562 RelocIterator() { initialize_misc(); }
563
564 public:
565 // constructor
566 RelocIterator(nmethod* nm, address begin = NULL, address limit = NULL);
567 RelocIterator(CodeSection* cb, address begin = NULL, address limit = NULL);
568
569 // get next reloc info, return !eos
570 bool next() {
571 _current++;
572 assert(_current <= _end, "must not overrun relocInfo");
573 if (_current == _end) {
574 set_has_current(false);
575 return false;
576 }
577 set_has_current(true);
578
579 if (_current->is_prefix()) {
580 advance_over_prefix();
581 assert(!current()->is_prefix(), "only one prefix at a time");
582 }
583
584 _addr += _current->addr_offset();
585
586 if (_limit != NULL && _addr >= _limit) {
587 set_has_current(false);
588 return false;
589 }
590
591 if (relocInfo::have_format) _format = current()->format();
592 return true;
593 }
594
595 // accessors
596 address limit() const { return _limit; }
597 void set_limit(address x);
598 relocType type() const { return current()->type(); }
599 int format() const { return (relocInfo::have_format) ? current()->format() : 0; }
600 address addr() const { return _addr; }
601 nmethod* code() const { return _code; }
602 short* data() const { return _data; }
603 int datalen() const { return _datalen; }
604 bool has_current() const { return _datalen >= 0; }
605
606 void set_addr(address addr) { _addr = addr; }
607 bool addr_in_const() const;
608
609 address section_start(int n) const {
610 assert(_section_start[n], "must be initialized");
611 return _section_start[n];
612 }
613 address section_end(int n) const {
614 assert(_section_end[n], "must be initialized");
615 return _section_end[n];
616 }
617
618 // The address points to the affected displacement part of the instruction.
619 // For RISC, this is just the whole instruction.
620 // For Intel, this is an unaligned 32-bit word.
621
622 // type-specific relocation accessors: oop_Relocation* oop_reloc(), etc.
623 #define EACH_TYPE(name) \
624 inline name##_Relocation* name##_reloc();
625 APPLY_TO_RELOCATIONS(EACH_TYPE)
626 #undef EACH_TYPE
627 // generic relocation accessor; switches on type to call the above
628 Relocation* reloc();
629
630 // CodeBlob's have relocation indexes for faster random access:
631 static int locs_and_index_size(int code_size, int locs_size);
632 // Store an index into [dest_start+dest_count..dest_end).
633 // At dest_start[0..dest_count] is the actual relocation information.
634 // Everything else up to dest_end is free space for the index.
635 static void create_index(relocInfo* dest_begin, int dest_count, relocInfo* dest_end);
636
637 #ifndef PRODUCT
638 public:
639 void print();
640 void print_current();
641 #endif
642 };
643
644
645 // A Relocation is a flyweight object allocated within a RelocationHolder.
646 // It represents the relocation data of relocation record.
647 // So, the RelocIterator unpacks relocInfos into Relocations.
648
649 class Relocation VALUE_OBJ_CLASS_SPEC {
650 friend class RelocationHolder;
651 friend class RelocIterator;
652
653 private:
654 static void guarantee_size();
655
656 // When a relocation has been created by a RelocIterator,
657 // this field is non-null. It allows the relocation to know
658 // its context, such as the address to which it applies.
659 RelocIterator* _binding;
660
661 protected:
662 RelocIterator* binding() const {
663 assert(_binding != NULL, "must be bound");
664 return _binding;
665 }
666 void set_binding(RelocIterator* b) {
667 assert(_binding == NULL, "must be unbound");
668 _binding = b;
669 assert(_binding != NULL, "must now be bound");
670 }
671
672 Relocation() {
673 _binding = NULL;
674 }
675
676 static RelocationHolder newHolder() {
677 return RelocationHolder();
678 }
679
680 public:
681 void* operator new(size_t size, const RelocationHolder& holder) {
682 if (size > sizeof(holder._relocbuf)) guarantee_size();
683 assert((void* const *)holder.reloc() == &holder._relocbuf[0], "ptrs must agree");
684 return holder.reloc();
685 }
686
687 // make a generic relocation for a given type (if possible)
688 static RelocationHolder spec_simple(relocInfo::relocType rtype);
689
690 // here is the type-specific hook which writes relocation data:
691 virtual void pack_data_to(CodeSection* dest) { }
692
693 // here is the type-specific hook which reads (unpacks) relocation data:
694 virtual void unpack_data() {
695 assert(datalen()==0 || type()==relocInfo::none, "no data here");
696 }
697
698 static bool is_reloc_index(intptr_t index) {
699 return 0 < index && index < os::vm_page_size();
700 }
701
702 protected:
703 // Helper functions for pack_data_to() and unpack_data().
704
705 // Most of the compression logic is confined here.
706 // (The "immediate data" mechanism of relocInfo works independently
707 // of this stuff, and acts to further compress most 1-word data prefixes.)
708
709 // A variable-width int is encoded as a short if it will fit in 16 bits.
710 // The decoder looks at datalen to decide whether to unpack short or jint.
711 // Most relocation records are quite simple, containing at most two ints.
712
713 static bool is_short(jint x) { return x == (short)x; }
714 static short* add_short(short* p, int x) { *p++ = x; return p; }
715 static short* add_jint (short* p, jint x) {
716 *p++ = relocInfo::data0_from_int(x); *p++ = relocInfo::data1_from_int(x);
717 return p;
718 }
719 static short* add_var_int(short* p, jint x) { // add a variable-width int
720 if (is_short(x)) p = add_short(p, x);
721 else p = add_jint (p, x);
722 return p;
723 }
724
725 static short* pack_1_int_to(short* p, jint x0) {
726 // Format is one of: [] [x] [Xx]
727 if (x0 != 0) p = add_var_int(p, x0);
728 return p;
729 }
730 int unpack_1_int() {
731 assert(datalen() <= 2, "too much data");
732 return relocInfo::jint_data_at(0, data(), datalen());
733 }
734
735 // With two ints, the short form is used only if both ints are short.
736 short* pack_2_ints_to(short* p, jint x0, jint x1) {
737 // Format is one of: [] [x y?] [Xx Y?y]
738 if (x0 == 0 && x1 == 0) {
739 // no halfwords needed to store zeroes
740 } else if (is_short(x0) && is_short(x1)) {
741 // 1-2 halfwords needed to store shorts
742 p = add_short(p, x0); if (x1!=0) p = add_short(p, x1);
743 } else {
744 // 3-4 halfwords needed to store jints
745 p = add_jint(p, x0); p = add_var_int(p, x1);
746 }
747 return p;
748 }
749 void unpack_2_ints(jint& x0, jint& x1) {
750 int dlen = datalen();
751 short* dp = data();
752 if (dlen <= 2) {
753 x0 = relocInfo::short_data_at(0, dp, dlen);
754 x1 = relocInfo::short_data_at(1, dp, dlen);
755 } else {
756 assert(dlen <= 4, "too much data");
757 x0 = relocInfo::jint_data_at(0, dp, dlen);
758 x1 = relocInfo::jint_data_at(2, dp, dlen);
759 }
760 }
761
762 protected:
763 // platform-dependent utilities for decoding and patching instructions
764 void pd_set_data_value (address x, intptr_t off, bool verify_only = false); // a set or mem-ref
765 void pd_verify_data_value (address x, intptr_t off) { pd_set_data_value(x, off, true); }
766 address pd_call_destination (address orig_addr = NULL);
767 void pd_set_call_destination (address x);
768
769 // this extracts the address of an address in the code stream instead of the reloc data
770 address* pd_address_in_code ();
771
772 // this extracts an address from the code stream instead of the reloc data
773 address pd_get_address_from_code ();
774
775 // these convert from byte offsets, to scaled offsets, to addresses
776 static jint scaled_offset(address x, address base) {
777 int byte_offset = x - base;
778 int offset = -byte_offset / relocInfo::addr_unit();
779 assert(address_from_scaled_offset(offset, base) == x, "just checkin'");
780 return offset;
781 }
782 static jint scaled_offset_null_special(address x, address base) {
783 // Some relocations treat offset=0 as meaning NULL.
784 // Handle this extra convention carefully.
785 if (x == NULL) return 0;
786 assert(x != base, "offset must not be zero");
787 return scaled_offset(x, base);
788 }
789 static address address_from_scaled_offset(jint offset, address base) {
790 int byte_offset = -( offset * relocInfo::addr_unit() );
791 return base + byte_offset;
792 }
793
794 // these convert between indexes and addresses in the runtime system
795 static int32_t runtime_address_to_index(address runtime_address);
796 static address index_to_runtime_address(int32_t index);
797
798 // helpers for mapping between old and new addresses after a move or resize
799 address old_addr_for(address newa, const CodeBuffer* src, CodeBuffer* dest);
800 address new_addr_for(address olda, const CodeBuffer* src, CodeBuffer* dest);
801 void normalize_address(address& addr, const CodeSection* dest, bool allow_other_sections = false);
802
803 public:
804 // accessors which only make sense for a bound Relocation
805 address addr() const { return binding()->addr(); }
806 nmethod* code() const { return binding()->code(); }
807 bool addr_in_const() const { return binding()->addr_in_const(); }
808 protected:
809 short* data() const { return binding()->data(); }
810 int datalen() const { return binding()->datalen(); }
811 int format() const { return binding()->format(); }
812
813 public:
814 virtual relocInfo::relocType type() { return relocInfo::none; }
815
816 // is it a call instruction?
817 virtual bool is_call() { return false; }
818
819 // is it a data movement instruction?
820 virtual bool is_data() { return false; }
821
822 // some relocations can compute their own values
823 virtual address value();
824
825 // all relocations are able to reassert their values
826 virtual void set_value(address x);
827
828 virtual void clear_inline_cache() { }
829
830 // This method assumes that all virtual/static (inline) caches are cleared (since for static_call_type and
831 // ic_call_type is not always posisition dependent (depending on the state of the cache)). However, this is
832 // probably a reasonable assumption, since empty caches simplifies code reloacation.
833 virtual void fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest) { }
834
835 void print();
836 };
837
838
839 // certain inlines must be deferred until class Relocation is defined:
840
841 inline RelocationHolder::RelocationHolder() {
842 // initialize the vtbl, just to keep things type-safe
843 new(*this) Relocation();
844 }
845
846
847 inline RelocationHolder::RelocationHolder(Relocation* r) {
848 // wordwise copy from r (ok if it copies garbage after r)
849 for (int i = 0; i < _relocbuf_size; i++) {
850 _relocbuf[i] = ((void**)r)[i];
851 }
852 }
853
854
855 relocInfo::relocType RelocationHolder::type() const {
856 return reloc()->type();
857 }
858
859 // A DataRelocation always points at a memory or load-constant instruction..
860 // It is absolute on most machines, and the constant is split on RISCs.
861 // The specific subtypes are oop, external_word, and internal_word.
862 // By convention, the "value" does not include a separately reckoned "offset".
863 class DataRelocation : public Relocation {
864 public:
865 bool is_data() { return true; }
866
867 // both target and offset must be computed somehow from relocation data
868 virtual int offset() { return 0; }
869 address value() = 0;
870 void set_value(address x) { set_value(x, offset()); }
871 void set_value(address x, intptr_t o) {
872 if (addr_in_const())
873 *(address*)addr() = x;
874 else
875 pd_set_data_value(x, o);
876 }
877 void verify_value(address x) {
878 if (addr_in_const())
879 assert(*(address*)addr() == x, "must agree");
880 else
881 pd_verify_data_value(x, offset());
882 }
883
884 // The "o" (displacement) argument is relevant only to split relocations
885 // on RISC machines. In some CPUs (SPARC), the set-hi and set-lo ins'ns
886 // can encode more than 32 bits between them. This allows compilers to
887 // share set-hi instructions between addresses that differ by a small
888 // offset (e.g., different static variables in the same class).
889 // On such machines, the "x" argument to set_value on all set-lo
890 // instructions must be the same as the "x" argument for the
891 // corresponding set-hi instructions. The "o" arguments for the
892 // set-hi instructions are ignored, and must not affect the high-half
893 // immediate constant. The "o" arguments for the set-lo instructions are
894 // added into the low-half immediate constant, and must not overflow it.
895 };
896
897 // A CallRelocation always points at a call instruction.
898 // It is PC-relative on most machines.
899 class CallRelocation : public Relocation {
900 public:
901 bool is_call() { return true; }
902
903 address destination() { return pd_call_destination(); }
904 void set_destination(address x); // pd_set_call_destination
905
906 void fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest);
907 address value() { return destination(); }
908 void set_value(address x) { set_destination(x); }
909 };
910
911 class oop_Relocation : public DataRelocation {
912 relocInfo::relocType type() { return relocInfo::oop_type; }
913
914 public:
915 // encode in one of these formats: [] [n] [n l] [Nn l] [Nn Ll]
916 // an oop in the CodeBlob's oop pool
917 static RelocationHolder spec(int oop_index, int offset = 0) {
918 assert(oop_index > 0, "must be a pool-resident oop");
919 RelocationHolder rh = newHolder();
920 new(rh) oop_Relocation(oop_index, offset);
921 return rh;
922 }
923 // an oop in the instruction stream
924 static RelocationHolder spec_for_immediate() {
925 const int oop_index = 0;
926 const int offset = 0; // if you want an offset, use the oop pool
927 RelocationHolder rh = newHolder();
928 new(rh) oop_Relocation(oop_index, offset);
929 return rh;
930 }
931
932 private:
933 jint _oop_index; // if > 0, index into CodeBlob::oop_at
934 jint _offset; // byte offset to apply to the oop itself
935
936 oop_Relocation(int oop_index, int offset) {
937 _oop_index = oop_index; _offset = offset;
938 }
939
940 friend class RelocIterator;
941 oop_Relocation() { }
942
943 public:
944 int oop_index() { return _oop_index; }
945 int offset() { return _offset; }
946
947 // data is packed in "2_ints" format: [i o] or [Ii Oo]
948 void pack_data_to(CodeSection* dest);
949 void unpack_data();
950
951 void fix_oop_relocation(); // reasserts oop value
952
953 void verify_oop_relocation();
954
955 address value() { return (address) *oop_addr(); }
956
957 bool oop_is_immediate() { return oop_index() == 0; }
958
959 oop* oop_addr(); // addr or &pool[jint_data]
960 oop oop_value(); // *oop_addr
961 // Note: oop_value transparently converts Universe::non_oop_word to NULL.
962 };
963
964
965 // copy of oop_Relocation for now but may delete stuff in both/either
966 class metadata_Relocation : public DataRelocation {
967 relocInfo::relocType type() { return relocInfo::metadata_type; }
968
969 public:
970 // encode in one of these formats: [] [n] [n l] [Nn l] [Nn Ll]
971 // an metadata in the CodeBlob's metadata pool
972 static RelocationHolder spec(int metadata_index, int offset = 0) {
973 assert(metadata_index > 0, "must be a pool-resident metadata");
974 RelocationHolder rh = newHolder();
975 new(rh) metadata_Relocation(metadata_index, offset);
976 return rh;
977 }
978 // an metadata in the instruction stream
979 static RelocationHolder spec_for_immediate() {
980 const int metadata_index = 0;
981 const int offset = 0; // if you want an offset, use the metadata pool
982 RelocationHolder rh = newHolder();
983 new(rh) metadata_Relocation(metadata_index, offset);
984 return rh;
985 }
986
987 private:
988 jint _metadata_index; // if > 0, index into nmethod::metadata_at
989 jint _offset; // byte offset to apply to the metadata itself
990
991 metadata_Relocation(int metadata_index, int offset) {
992 _metadata_index = metadata_index; _offset = offset;
993 }
994
995 friend class RelocIterator;
996 metadata_Relocation() { }
997
998 // Fixes a Metadata pointer in the code. Most platforms embeds the
999 // Metadata pointer in the code at compile time so this is empty
1000 // for them.
1001 void pd_fix_value(address x);
1002
1003 public:
1004 int metadata_index() { return _metadata_index; }
1005 int offset() { return _offset; }
1006
1007 // data is packed in "2_ints" format: [i o] or [Ii Oo]
1008 void pack_data_to(CodeSection* dest);
1009 void unpack_data();
1010
1011 void fix_metadata_relocation(); // reasserts metadata value
1012
1013 void verify_metadata_relocation();
1014
1015 address value() { return (address) *metadata_addr(); }
1016
1017 bool metadata_is_immediate() { return metadata_index() == 0; }
1018
1019 Metadata** metadata_addr(); // addr or &pool[jint_data]
1020 Metadata* metadata_value(); // *metadata_addr
1021 // Note: metadata_value transparently converts Universe::non_metadata_word to NULL.
1022 };
1023
1024
1025 class virtual_call_Relocation : public CallRelocation {
1026 relocInfo::relocType type() { return relocInfo::virtual_call_type; }
1027
1028 public:
1029 // "cached_value" points to the first associated set-oop.
1030 // The oop_limit helps find the last associated set-oop.
1031 // (See comments at the top of this file.)
1032 static RelocationHolder spec(address cached_value) {
1033 RelocationHolder rh = newHolder();
1034 new(rh) virtual_call_Relocation(cached_value);
1035 return rh;
1036 }
1037
1038 virtual_call_Relocation(address cached_value) {
1039 _cached_value = cached_value;
1040 assert(cached_value != NULL, "first oop address must be specified");
1041 }
1042
1043 private:
1044 address _cached_value; // location of set-value instruction
1045
1046 friend class RelocIterator;
1047 virtual_call_Relocation() { }
1048
1049
1050 public:
1051 address cached_value();
1052
1053 // data is packed as scaled offsets in "2_ints" format: [f l] or [Ff Ll]
1054 // oop_limit is set to 0 if the limit falls somewhere within the call.
1055 // When unpacking, a zero oop_limit is taken to refer to the end of the call.
1056 // (This has the effect of bringing in the call's delay slot on SPARC.)
1057 void pack_data_to(CodeSection* dest);
1058 void unpack_data();
1059
1060 void clear_inline_cache();
1061 };
1062
1063
1064 class opt_virtual_call_Relocation : public CallRelocation {
1065 relocInfo::relocType type() { return relocInfo::opt_virtual_call_type; }
1066
1067 public:
1068 static RelocationHolder spec() {
1069 RelocationHolder rh = newHolder();
1070 new(rh) opt_virtual_call_Relocation();
1071 return rh;
1072 }
1073
1074 private:
1075 friend class RelocIterator;
1076 opt_virtual_call_Relocation() { }
1077
1078 public:
1079 void clear_inline_cache();
1080
1081 // find the matching static_stub
1082 address static_stub();
1083 };
1084
1085
1086 class static_call_Relocation : public CallRelocation {
1087 relocInfo::relocType type() { return relocInfo::static_call_type; }
1088
1089 public:
1090 static RelocationHolder spec() {
1091 RelocationHolder rh = newHolder();
1092 new(rh) static_call_Relocation();
1093 return rh;
1094 }
1095
1096 private:
1097 friend class RelocIterator;
1098 static_call_Relocation() { }
1099
1100 public:
1101 void clear_inline_cache();
1102
1103 // find the matching static_stub
1104 address static_stub();
1105 };
1106
1107 class static_stub_Relocation : public Relocation {
1108 relocInfo::relocType type() { return relocInfo::static_stub_type; }
1109
1110 public:
1111 static RelocationHolder spec(address static_call) {
1112 RelocationHolder rh = newHolder();
1113 new(rh) static_stub_Relocation(static_call);
1114 return rh;
1115 }
1116
1117 private:
1118 address _static_call; // location of corresponding static_call
1119
1120 static_stub_Relocation(address static_call) {
1121 _static_call = static_call;
1122 }
1123
1124 friend class RelocIterator;
1125 static_stub_Relocation() { }
1126
1127 public:
1128 void clear_inline_cache();
1129
1130 address static_call() { return _static_call; }
1131
1132 // data is packed as a scaled offset in "1_int" format: [c] or [Cc]
1133 void pack_data_to(CodeSection* dest);
1134 void unpack_data();
1135 };
1136
1137 class runtime_call_Relocation : public CallRelocation {
1138 relocInfo::relocType type() { return relocInfo::runtime_call_type; }
1139
1140 public:
1141 static RelocationHolder spec() {
1142 RelocationHolder rh = newHolder();
1143 new(rh) runtime_call_Relocation();
1144 return rh;
1145 }
1146
1147 private:
1148 friend class RelocIterator;
1149 runtime_call_Relocation() { }
1150
1151 public:
1152 };
1153
1154 // Trampoline Relocations.
1155 // A trampoline allows to encode a small branch in the code, even if there
1156 // is the chance that this branch can not reach all possible code locations.
1157 // If the relocation finds that a branch is too far for the instruction
1158 // in the code, it can patch it to jump to the trampoline where is
1159 // sufficient space for a far branch. Needed on PPC.
1160 class trampoline_stub_Relocation : public Relocation {
1161 relocInfo::relocType type() { return relocInfo::trampoline_stub_type; }
1162
1163 public:
1164 static RelocationHolder spec(address static_call) {
1165 RelocationHolder rh = newHolder();
1166 return (new (rh) trampoline_stub_Relocation(static_call));
1167 }
1168
1169 private:
1170 address _owner; // Address of the NativeCall that owns the trampoline.
1171
1172 trampoline_stub_Relocation(address owner) {
1173 _owner = owner;
1174 }
1175
1176 friend class RelocIterator;
1177 trampoline_stub_Relocation() { }
1178
1179 public:
1180
1181 // Return the address of the NativeCall that owns the trampoline.
1182 address owner() { return _owner; }
1183
1184 void pack_data_to(CodeSection * dest);
1185 void unpack_data();
1186
1187 // Find the trampoline stub for a call.
1188 static address get_trampoline_for(address call, nmethod* code);
1189 };
1190
1191 class external_word_Relocation : public DataRelocation {
1192 relocInfo::relocType type() { return relocInfo::external_word_type; }
1193
1194 public:
1195 static RelocationHolder spec(address target) {
1196 assert(target != NULL, "must not be null");
1197 RelocationHolder rh = newHolder();
1198 new(rh) external_word_Relocation(target);
1199 return rh;
1200 }
1201
1202 // Use this one where all 32/64 bits of the target live in the code stream.
1203 // The target must be an intptr_t, and must be absolute (not relative).
1204 static RelocationHolder spec_for_immediate() {
1205 RelocationHolder rh = newHolder();
1206 new(rh) external_word_Relocation(NULL);
1207 return rh;
1208 }
1209
1210 // Some address looking values aren't safe to treat as relocations
1211 // and should just be treated as constants.
1212 static bool can_be_relocated(address target) {
1213 return target != NULL && !is_reloc_index((intptr_t)target);
1214 }
1215
1216 private:
1217 address _target; // address in runtime
1218
1219 external_word_Relocation(address target) {
1220 _target = target;
1221 }
1222
1223 friend class RelocIterator;
1224 external_word_Relocation() { }
1225
1226 public:
1227 // data is packed as a well-known address in "1_int" format: [a] or [Aa]
1228 // The function runtime_address_to_index is used to turn full addresses
1229 // to short indexes, if they are pre-registered by the stub mechanism.
1230 // If the "a" value is 0 (i.e., _target is NULL), the address is stored
1231 // in the code stream. See external_word_Relocation::target().
1232 void pack_data_to(CodeSection* dest);
1233 void unpack_data();
1234
1235 void fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest);
1236 address target(); // if _target==NULL, fetch addr from code stream
1237 address value() { return target(); }
1238 };
1239
1240 class internal_word_Relocation : public DataRelocation {
1241 relocInfo::relocType type() { return relocInfo::internal_word_type; }
1242
1243 public:
1244 static RelocationHolder spec(address target) {
1245 assert(target != NULL, "must not be null");
1246 RelocationHolder rh = newHolder();
1247 new(rh) internal_word_Relocation(target);
1248 return rh;
1249 }
1250
1251 // use this one where all the bits of the target can fit in the code stream:
1252 static RelocationHolder spec_for_immediate() {
1253 RelocationHolder rh = newHolder();
1254 new(rh) internal_word_Relocation(NULL);
1255 return rh;
1256 }
1257
1258 internal_word_Relocation(address target) {
1259 _target = target;
1260 _section = -1; // self-relative
1261 }
1262
1263 protected:
1264 address _target; // address in CodeBlob
1265 int _section; // section providing base address, if any
1266
1267 friend class RelocIterator;
1268 internal_word_Relocation() { }
1269
1270 // bit-width of LSB field in packed offset, if section >= 0
1271 enum { section_width = 2 }; // must equal CodeBuffer::sect_bits
1272
1273 public:
1274 // data is packed as a scaled offset in "1_int" format: [o] or [Oo]
1275 // If the "o" value is 0 (i.e., _target is NULL), the offset is stored
1276 // in the code stream. See internal_word_Relocation::target().
1277 // If _section is not -1, it is appended to the low bits of the offset.
1278 void pack_data_to(CodeSection* dest);
1279 void unpack_data();
1280
1281 void fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest);
1282 address target(); // if _target==NULL, fetch addr from code stream
1283 int section() { return _section; }
1284 address value() { return target(); }
1285 };
1286
1287 class section_word_Relocation : public internal_word_Relocation {
1288 relocInfo::relocType type() { return relocInfo::section_word_type; }
1289
1290 public:
1291 static RelocationHolder spec(address target, int section) {
1292 RelocationHolder rh = newHolder();
1293 new(rh) section_word_Relocation(target, section);
1294 return rh;
1295 }
1296
1297 section_word_Relocation(address target, int section) {
1298 assert(target != NULL, "must not be null");
1299 assert(section >= 0, "must be a valid section");
1300 _target = target;
1301 _section = section;
1302 }
1303
1304 //void pack_data_to -- inherited
1305 void unpack_data();
1306
1307 private:
1308 friend class RelocIterator;
1309 section_word_Relocation() { }
1310 };
1311
1312
1313 class poll_Relocation : public Relocation {
1314 bool is_data() { return true; }
1315 relocInfo::relocType type() { return relocInfo::poll_type; }
1316 void fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest);
1317 };
1318
1319 class poll_return_Relocation : public Relocation {
1320 bool is_data() { return true; }
1321 relocInfo::relocType type() { return relocInfo::poll_return_type; }
1322 void fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest);
1323 };
1324
1325 // We know all the xxx_Relocation classes, so now we can define these:
1326 #define EACH_CASE(name) \
1327 inline name##_Relocation* RelocIterator::name##_reloc() { \
1328 assert(type() == relocInfo::name##_type, "type must agree"); \
1329 /* The purpose of the placed "new" is to re-use the same */ \
1330 /* stack storage for each new iteration. */ \
1331 name##_Relocation* r = new(_rh) name##_Relocation(); \
1332 r->set_binding(this); \
1333 r->name##_Relocation::unpack_data(); \
1334 return r; \
1335 }
1336 APPLY_TO_RELOCATIONS(EACH_CASE);
1337 #undef EACH_CASE
1338
1339 inline RelocIterator::RelocIterator(nmethod* nm, address begin, address limit) {
1340 initialize(nm, begin, limit);
1341 }
1342
1343 #endif // SHARE_VM_CODE_RELOCINFO_HPP