1/*
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3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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24
25#ifndef SHARE_CODE_RELOCINFO_HPP
26#define SHARE_CODE_RELOCINFO_HPP
27
28#include "runtime/os.hpp"
29#include "utilities/macros.hpp"
30
31class nmethod;
32class CodeBlob;
33class CompiledMethod;
34class Metadata;
35class NativeMovConstReg;
36
37// Types in this file:
38// relocInfo
39// One element of an array of halfwords encoding compressed relocations.
40// Also, the source of relocation types (relocInfo::oop_type, ...).
41// Relocation
42// A flyweight object representing a single relocation.
43// It is fully unpacked from the compressed relocation array.
44// metadata_Relocation, ... (subclasses of Relocation)
45// The location of some type-specific operations (metadata_addr, ...).
46// Also, the source of relocation specs (metadata_Relocation::spec, ...).
47// oop_Relocation, ... (subclasses of Relocation)
48// oops in the code stream (strings, class loaders)
49// Also, the source of relocation specs (oop_Relocation::spec, ...).
50// RelocationHolder
51// A value type which acts as a union holding a Relocation object.
52// Represents a relocation spec passed into a CodeBuffer during assembly.
53// RelocIterator
54// A StackObj which iterates over the relocations associated with
55// a range of code addresses. Can be used to operate a copy of code.
56// BoundRelocation
57// An _internal_ type shared by packers and unpackers of relocations.
58// It pastes together a RelocationHolder with some pointers into
59// code and relocInfo streams.
60
61
62// Notes on relocType:
63//
64// These hold enough information to read or write a value embedded in
65// the instructions of an CodeBlob. They're used to update:
66//
67// 1) embedded oops (isOop() == true)
68// 2) inline caches (isIC() == true)
69// 3) runtime calls (isRuntimeCall() == true)
70// 4) internal word ref (isInternalWord() == true)
71// 5) external word ref (isExternalWord() == true)
72//
73// when objects move (GC) or if code moves (compacting the code heap).
74// They are also used to patch the code (if a call site must change)
75//
76// A relocInfo is represented in 16 bits:
77// 4 bits indicating the relocation type
78// 12 bits indicating the offset from the previous relocInfo address
79//
80// The offsets accumulate along the relocInfo stream to encode the
81// address within the CodeBlob, which is named RelocIterator::addr().
82// The address of a particular relocInfo always points to the first
83// byte of the relevant instruction (and not to any of its subfields
84// or embedded immediate constants).
85//
86// The offset value is scaled appropriately for the target machine.
87// (See relocInfo_<arch>.hpp for the offset scaling.)
88//
89// On some machines, there may also be a "format" field which may provide
90// additional information about the format of the instruction stream
91// at the corresponding code address. The format value is usually zero.
92// Any machine (such as Intel) whose instructions can sometimes contain
93// more than one relocatable constant needs format codes to distinguish
94// which operand goes with a given relocation.
95//
96// If the target machine needs N format bits, the offset has 12-N bits,
97// the format is encoded between the offset and the type, and the
98// relocInfo_<arch>.hpp file has manifest constants for the format codes.
99//
100// If the type is "data_prefix_tag" then the offset bits are further encoded,
101// and in fact represent not a code-stream offset but some inline data.
102// The data takes the form of a counted sequence of halfwords, which
103// precedes the actual relocation record. (Clients never see it directly.)
104// The interpetation of this extra data depends on the relocation type.
105//
106// On machines that have 32-bit immediate fields, there is usually
107// little need for relocation "prefix" data, because the instruction stream
108// is a perfectly reasonable place to store the value. On machines in
109// which 32-bit values must be "split" across instructions, the relocation
110// data is the "true" specification of the value, which is then applied
111// to some field of the instruction (22 or 13 bits, on SPARC).
112//
113// Whenever the location of the CodeBlob changes, any PC-relative
114// relocations, and any internal_word_type relocations, must be reapplied.
115// After the GC runs, oop_type relocations must be reapplied.
116//
117//
118// Here are meanings of the types:
119//
120// relocInfo::none -- a filler record
121// Value: none
122// Instruction: The corresponding code address is ignored
123// Data: Any data prefix and format code are ignored
124// (This means that any relocInfo can be disabled by setting
125// its type to none. See relocInfo::remove.)
126//
127// relocInfo::oop_type, relocInfo::metadata_type -- a reference to an oop or meta data
128// Value: an oop, or else the address (handle) of an oop
129// Instruction types: memory (load), set (load address)
130// Data: [] an oop stored in 4 bytes of instruction
131// [n] n is the index of an oop in the CodeBlob's oop pool
132// [[N]n l] and l is a byte offset to be applied to the oop
133// [Nn Ll] both index and offset may be 32 bits if necessary
134// Here is a special hack, used only by the old compiler:
135// [[N]n 00] the value is the __address__ of the nth oop in the pool
136// (Note that the offset allows optimal references to class variables.)
137//
138// relocInfo::internal_word_type -- an address within the same CodeBlob
139// relocInfo::section_word_type -- same, but can refer to another section
140// Value: an address in the CodeBlob's code or constants section
141// Instruction types: memory (load), set (load address)
142// Data: [] stored in 4 bytes of instruction
143// [[L]l] a relative offset (see [About Offsets] below)
144// In the case of section_word_type, the offset is relative to a section
145// base address, and the section number (e.g., SECT_INSTS) is encoded
146// into the low two bits of the offset L.
147//
148// relocInfo::external_word_type -- a fixed address in the runtime system
149// Value: an address
150// Instruction types: memory (load), set (load address)
151// Data: [] stored in 4 bytes of instruction
152// [n] the index of a "well-known" stub (usual case on RISC)
153// [Ll] a 32-bit address
154//
155// relocInfo::runtime_call_type -- a fixed subroutine in the runtime system
156// Value: an address
157// Instruction types: PC-relative call (or a PC-relative branch)
158// Data: [] stored in 4 bytes of instruction
159//
160// relocInfo::static_call_type -- a static call
161// Value: an CodeBlob, a stub, or a fixup routine
162// Instruction types: a call
163// Data: []
164// The identity of the callee is extracted from debugging information.
165// //%note reloc_3
166//
167// relocInfo::virtual_call_type -- a virtual call site (which includes an inline
168// cache)
169// Value: an CodeBlob, a stub, the interpreter, or a fixup routine
170// Instruction types: a call, plus some associated set-oop instructions
171// Data: [] the associated set-oops are adjacent to the call
172// [n] n is a relative offset to the first set-oop
173// [[N]n l] and l is a limit within which the set-oops occur
174// [Nn Ll] both n and l may be 32 bits if necessary
175// The identity of the callee is extracted from debugging information.
176//
177// relocInfo::opt_virtual_call_type -- a virtual call site that is statically bound
178//
179// Same info as a static_call_type. We use a special type, so the handling of
180// virtuals and statics are separated.
181//
182//
183// The offset n points to the first set-oop. (See [About Offsets] below.)
184// In turn, the set-oop instruction specifies or contains an oop cell devoted
185// exclusively to the IC call, which can be patched along with the call.
186//
187// The locations of any other set-oops are found by searching the relocation
188// information starting at the first set-oop, and continuing until all
189// relocations up through l have been inspected. The value l is another
190// relative offset. (Both n and l are relative to the call's first byte.)
191//
192// The limit l of the search is exclusive. However, if it points within
193// the call (e.g., offset zero), it is adjusted to point after the call and
194// any associated machine-specific delay slot.
195//
196// Since the offsets could be as wide as 32-bits, these conventions
197// put no restrictions whatever upon code reorganization.
198//
199// The compiler is responsible for ensuring that transition from a clean
200// state to a monomorphic compiled state is MP-safe. This implies that
201// the system must respond well to intermediate states where a random
202// subset of the set-oops has been correctly from the clean state
203// upon entry to the VEP of the compiled method. In the case of a
204// machine (Intel) with a single set-oop instruction, the 32-bit
205// immediate field must not straddle a unit of memory coherence.
206// //%note reloc_3
207//
208// relocInfo::static_stub_type -- an extra stub for each static_call_type
209// Value: none
210// Instruction types: a virtual call: { set_oop; jump; }
211// Data: [[N]n] the offset of the associated static_call reloc
212// This stub becomes the target of a static call which must be upgraded
213// to a virtual call (because the callee is interpreted).
214// See [About Offsets] below.
215// //%note reloc_2
216//
217// relocInfo::poll_[return_]type -- a safepoint poll
218// Value: none
219// Instruction types: memory load or test
220// Data: none
221//
222// For example:
223//
224// INSTRUCTIONS RELOC: TYPE PREFIX DATA
225// ------------ ---- -----------
226// sethi %hi(myObject), R oop_type [n(myObject)]
227// ld [R+%lo(myObject)+fldOffset], R2 oop_type [n(myObject) fldOffset]
228// add R2, 1, R2
229// st R2, [R+%lo(myObject)+fldOffset] oop_type [n(myObject) fldOffset]
230//%note reloc_1
231//
232// This uses 4 instruction words, 8 relocation halfwords,
233// and an entry (which is sharable) in the CodeBlob's oop pool,
234// for a total of 36 bytes.
235//
236// Note that the compiler is responsible for ensuring the "fldOffset" when
237// added to "%lo(myObject)" does not overflow the immediate fields of the
238// memory instructions.
239//
240//
241// [About Offsets] Relative offsets are supplied to this module as
242// positive byte offsets, but they may be internally stored scaled
243// and/or negated, depending on what is most compact for the target
244// system. Since the object pointed to by the offset typically
245// precedes the relocation address, it is profitable to store
246// these negative offsets as positive numbers, but this decision
247// is internal to the relocation information abstractions.
248//
249
250class Relocation;
251class CodeBuffer;
252class CodeSection;
253class RelocIterator;
254
255class relocInfo {
256 friend class RelocIterator;
257 public:
258 enum relocType {
259 none = 0, // Used when no relocation should be generated
260 oop_type = 1, // embedded oop
261 virtual_call_type = 2, // a standard inline cache call for a virtual send
262 opt_virtual_call_type = 3, // a virtual call that has been statically bound (i.e., no IC cache)
263 static_call_type = 4, // a static send
264 static_stub_type = 5, // stub-entry for static send (takes care of interpreter case)
265 runtime_call_type = 6, // call to fixed external routine
266 external_word_type = 7, // reference to fixed external address
267 internal_word_type = 8, // reference within the current code blob
268 section_word_type = 9, // internal, but a cross-section reference
269 poll_type = 10, // polling instruction for safepoints
270 poll_return_type = 11, // polling instruction for safepoints at return
271 metadata_type = 12, // metadata that used to be oops
272 trampoline_stub_type = 13, // stub-entry for trampoline
273 runtime_call_w_cp_type = 14, // Runtime call which may load its target from the constant pool
274 data_prefix_tag = 15, // tag for a prefix (carries data arguments)
275 type_mask = 15 // A mask which selects only the above values
276 };
277
278 protected:
279 unsigned short _value;
280
281 enum RawBitsToken { RAW_BITS };
282 relocInfo(relocType type, RawBitsToken ignore, int bits)
283 : _value((type << nontype_width) + bits) { }
284
285 relocInfo(relocType type, RawBitsToken ignore, int off, int f)
286 : _value((type << nontype_width) + (off / (unsigned)offset_unit) + (f << offset_width)) { }
287
288 public:
289 // constructor
290 relocInfo(relocType type, int offset, int format = 0)
291#ifndef ASSERT
292 {
293 (*this) = relocInfo(type, RAW_BITS, offset, format);
294 }
295#else
296 // Put a bunch of assertions out-of-line.
297 ;
298#endif
299
300 #define APPLY_TO_RELOCATIONS(visitor) \
301 visitor(oop) \
302 visitor(metadata) \
303 visitor(virtual_call) \
304 visitor(opt_virtual_call) \
305 visitor(static_call) \
306 visitor(static_stub) \
307 visitor(runtime_call) \
308 visitor(runtime_call_w_cp) \
309 visitor(external_word) \
310 visitor(internal_word) \
311 visitor(poll) \
312 visitor(poll_return) \
313 visitor(section_word) \
314 visitor(trampoline_stub) \
315
316
317 public:
318 enum {
319 value_width = sizeof(unsigned short) * BitsPerByte,
320 type_width = 4, // == log2(type_mask+1)
321 nontype_width = value_width - type_width,
322 datalen_width = nontype_width-1,
323 datalen_tag = 1 << datalen_width, // or-ed into _value
324 datalen_limit = 1 << datalen_width,
325 datalen_mask = (1 << datalen_width)-1
326 };
327
328 // accessors
329 public:
330 relocType type() const { return (relocType)((unsigned)_value >> nontype_width); }
331 int format() const { return format_mask==0? 0: format_mask &
332 ((unsigned)_value >> offset_width); }
333 int addr_offset() const { assert(!is_prefix(), "must have offset");
334 return (_value & offset_mask)*offset_unit; }
335
336 protected:
337 const short* data() const { assert(is_datalen(), "must have data");
338 return (const short*)(this + 1); }
339 int datalen() const { assert(is_datalen(), "must have data");
340 return (_value & datalen_mask); }
341 int immediate() const { assert(is_immediate(), "must have immed");
342 return (_value & datalen_mask); }
343 public:
344 static int addr_unit() { return offset_unit; }
345 static int offset_limit() { return (1 << offset_width) * offset_unit; }
346
347 void set_type(relocType type);
348
349 void remove() { set_type(none); }
350
351 protected:
352 bool is_none() const { return type() == none; }
353 bool is_prefix() const { return type() == data_prefix_tag; }
354 bool is_datalen() const { assert(is_prefix(), "must be prefix");
355 return (_value & datalen_tag) != 0; }
356 bool is_immediate() const { assert(is_prefix(), "must be prefix");
357 return (_value & datalen_tag) == 0; }
358
359 public:
360 // Occasionally records of type relocInfo::none will appear in the stream.
361 // We do not bother to filter these out, but clients should ignore them.
362 // These records serve as "filler" in three ways:
363 // - to skip large spans of unrelocated code (this is rare)
364 // - to pad out the relocInfo array to the required oop alignment
365 // - to disable old relocation information which is no longer applicable
366
367 inline friend relocInfo filler_relocInfo();
368
369 // Every non-prefix relocation may be preceded by at most one prefix,
370 // which supplies 1 or more halfwords of associated data. Conventionally,
371 // an int is represented by 0, 1, or 2 halfwords, depending on how
372 // many bits are required to represent the value. (In addition,
373 // if the sole halfword is a 10-bit unsigned number, it is made
374 // "immediate" in the prefix header word itself. This optimization
375 // is invisible outside this module.)
376
377 inline friend relocInfo prefix_relocInfo(int datalen);
378
379 protected:
380 // an immediate relocInfo optimizes a prefix with one 10-bit unsigned value
381 static relocInfo immediate_relocInfo(int data0) {
382 assert(fits_into_immediate(data0), "data0 in limits");
383 return relocInfo(relocInfo::data_prefix_tag, RAW_BITS, data0);
384 }
385 static bool fits_into_immediate(int data0) {
386 return (data0 >= 0 && data0 < datalen_limit);
387 }
388
389 public:
390 // Support routines for compilers.
391
392 // This routine takes an infant relocInfo (unprefixed) and
393 // edits in its prefix, if any. It also updates dest.locs_end.
394 void initialize(CodeSection* dest, Relocation* reloc);
395
396 // This routine updates a prefix and returns the limit pointer.
397 // It tries to compress the prefix from 32 to 16 bits, and if
398 // successful returns a reduced "prefix_limit" pointer.
399 relocInfo* finish_prefix(short* prefix_limit);
400
401 // bit-packers for the data array:
402
403 // As it happens, the bytes within the shorts are ordered natively,
404 // but the shorts within the word are ordered big-endian.
405 // This is an arbitrary choice, made this way mainly to ease debugging.
406 static int data0_from_int(jint x) { return x >> value_width; }
407 static int data1_from_int(jint x) { return (short)x; }
408 static jint jint_from_data(short* data) {
409 return (data[0] << value_width) + (unsigned short)data[1];
410 }
411
412 static jint short_data_at(int n, short* data, int datalen) {
413 return datalen > n ? data[n] : 0;
414 }
415
416 static jint jint_data_at(int n, short* data, int datalen) {
417 return datalen > n+1 ? jint_from_data(&data[n]) : short_data_at(n, data, datalen);
418 }
419
420 // Update methods for relocation information
421 // (since code is dynamically patched, we also need to dynamically update the relocation info)
422 // Both methods takes old_type, so it is able to performe sanity checks on the information removed.
423 static void change_reloc_info_for_address(RelocIterator *itr, address pc, relocType old_type, relocType new_type);
424
425 // Machine dependent stuff
426#include CPU_HEADER(relocInfo)
427
428 protected:
429 // Derived constant, based on format_width which is PD:
430 enum {
431 offset_width = nontype_width - format_width,
432 offset_mask = (1<<offset_width) - 1,
433 format_mask = (1<<format_width) - 1
434 };
435 public:
436 enum {
437#ifdef _LP64
438 // for use in format
439 // format_width must be at least 1 on _LP64
440 narrow_oop_in_const = 1,
441#endif
442 // Conservatively large estimate of maximum length (in shorts)
443 // of any relocation record.
444 // Extended format is length prefix, data words, and tag/offset suffix.
445 length_limit = 1 + 1 + (3*BytesPerWord/BytesPerShort) + 1,
446 have_format = format_width > 0
447 };
448};
449
450#define FORWARD_DECLARE_EACH_CLASS(name) \
451class name##_Relocation;
452APPLY_TO_RELOCATIONS(FORWARD_DECLARE_EACH_CLASS)
453#undef FORWARD_DECLARE_EACH_CLASS
454
455
456
457inline relocInfo filler_relocInfo() {
458 return relocInfo(relocInfo::none, relocInfo::offset_limit() - relocInfo::offset_unit);
459}
460
461inline relocInfo prefix_relocInfo(int datalen = 0) {
462 assert(relocInfo::fits_into_immediate(datalen), "datalen in limits");
463 return relocInfo(relocInfo::data_prefix_tag, relocInfo::RAW_BITS, relocInfo::datalen_tag | datalen);
464}
465
466
467// Holder for flyweight relocation objects.
468// Although the flyweight subclasses are of varying sizes,
469// the holder is "one size fits all".
470class RelocationHolder {
471 friend class Relocation;
472 friend class CodeSection;
473
474 private:
475 // this preallocated memory must accommodate all subclasses of Relocation
476 // (this number is assertion-checked in Relocation::operator new)
477 enum { _relocbuf_size = 5 };
478 void* _relocbuf[ _relocbuf_size ];
479
480 public:
481 Relocation* reloc() const { return (Relocation*) &_relocbuf[0]; }
482 inline relocInfo::relocType type() const;
483
484 // Add a constant offset to a relocation. Helper for class Address.
485 RelocationHolder plus(int offset) const;
486
487 inline RelocationHolder(); // initializes type to none
488
489 inline RelocationHolder(Relocation* r); // make a copy
490
491 static const RelocationHolder none;
492};
493
494// A RelocIterator iterates through the relocation information of a CodeBlob.
495// It is a variable BoundRelocation which is able to take on successive
496// values as it is advanced through a code stream.
497// Usage:
498// RelocIterator iter(nm);
499// while (iter.next()) {
500// iter.reloc()->some_operation();
501// }
502// or:
503// RelocIterator iter(nm);
504// while (iter.next()) {
505// switch (iter.type()) {
506// case relocInfo::oop_type :
507// case relocInfo::ic_type :
508// case relocInfo::prim_type :
509// case relocInfo::uncommon_type :
510// case relocInfo::runtime_call_type :
511// case relocInfo::internal_word_type:
512// case relocInfo::external_word_type:
513// ...
514// }
515// }
516
517class RelocIterator : public StackObj {
518 enum { SECT_LIMIT = 3 }; // must be equal to CodeBuffer::SECT_LIMIT, checked in ctor
519 friend class Relocation;
520 friend class relocInfo; // for change_reloc_info_for_address only
521 typedef relocInfo::relocType relocType;
522
523 private:
524 address _limit; // stop producing relocations after this _addr
525 relocInfo* _current; // the current relocation information
526 relocInfo* _end; // end marker; we're done iterating when _current == _end
527 CompiledMethod* _code; // compiled method containing _addr
528 address _addr; // instruction to which the relocation applies
529 short _databuf; // spare buffer for compressed data
530 short* _data; // pointer to the relocation's data
531 short _datalen; // number of halfwords in _data
532
533 // Base addresses needed to compute targets of section_word_type relocs.
534 address _section_start[SECT_LIMIT];
535 address _section_end [SECT_LIMIT];
536
537 void set_has_current(bool b) {
538 _datalen = !b ? -1 : 0;
539 debug_only(_data = NULL);
540 }
541 void set_current(relocInfo& ri) {
542 _current = &ri;
543 set_has_current(true);
544 }
545
546 RelocationHolder _rh; // where the current relocation is allocated
547
548 relocInfo* current() const { assert(has_current(), "must have current");
549 return _current; }
550
551 void set_limits(address begin, address limit);
552
553 void advance_over_prefix(); // helper method
554
555 void initialize_misc();
556
557 void initialize(CompiledMethod* nm, address begin, address limit);
558
559 RelocIterator() { initialize_misc(); }
560
561 public:
562 // constructor
563 RelocIterator(CompiledMethod* nm, address begin = NULL, address limit = NULL);
564 RelocIterator(CodeSection* cb, address begin = NULL, address limit = NULL);
565
566 // get next reloc info, return !eos
567 bool next() {
568 _current++;
569 assert(_current <= _end, "must not overrun relocInfo");
570 if (_current == _end) {
571 set_has_current(false);
572 return false;
573 }
574 set_has_current(true);
575
576 if (_current->is_prefix()) {
577 advance_over_prefix();
578 assert(!current()->is_prefix(), "only one prefix at a time");
579 }
580
581 _addr += _current->addr_offset();
582
583 if (_limit != NULL && _addr >= _limit) {
584 set_has_current(false);
585 return false;
586 }
587
588 return true;
589 }
590
591 // accessors
592 address limit() const { return _limit; }
593 relocType type() const { return current()->type(); }
594 int format() const { return (relocInfo::have_format) ? current()->format() : 0; }
595 address addr() const { return _addr; }
596 CompiledMethod* code() const { return _code; }
597 short* data() const { return _data; }
598 int datalen() const { return _datalen; }
599 bool has_current() const { return _datalen >= 0; }
600 bool addr_in_const() const;
601
602 address section_start(int n) const {
603 assert(_section_start[n], "must be initialized");
604 return _section_start[n];
605 }
606 address section_end(int n) const {
607 assert(_section_end[n], "must be initialized");
608 return _section_end[n];
609 }
610
611 // The address points to the affected displacement part of the instruction.
612 // For RISC, this is just the whole instruction.
613 // For Intel, this is an unaligned 32-bit word.
614
615 // type-specific relocation accessors: oop_Relocation* oop_reloc(), etc.
616 #define EACH_TYPE(name) \
617 inline name##_Relocation* name##_reloc();
618 APPLY_TO_RELOCATIONS(EACH_TYPE)
619 #undef EACH_TYPE
620 // generic relocation accessor; switches on type to call the above
621 Relocation* reloc();
622
623#ifndef PRODUCT
624 public:
625 void print();
626 void print_current();
627#endif
628};
629
630
631// A Relocation is a flyweight object allocated within a RelocationHolder.
632// It represents the relocation data of relocation record.
633// So, the RelocIterator unpacks relocInfos into Relocations.
634
635class Relocation {
636 friend class RelocationHolder;
637 friend class RelocIterator;
638
639 private:
640 static void guarantee_size();
641
642 // When a relocation has been created by a RelocIterator,
643 // this field is non-null. It allows the relocation to know
644 // its context, such as the address to which it applies.
645 RelocIterator* _binding;
646
647 protected:
648 RelocIterator* binding() const {
649 assert(_binding != NULL, "must be bound");
650 return _binding;
651 }
652 void set_binding(RelocIterator* b) {
653 assert(_binding == NULL, "must be unbound");
654 _binding = b;
655 assert(_binding != NULL, "must now be bound");
656 }
657
658 Relocation() {
659 _binding = NULL;
660 }
661
662 static RelocationHolder newHolder() {
663 return RelocationHolder();
664 }
665
666 public:
667 void* operator new(size_t size, const RelocationHolder& holder) throw() {
668 if (size > sizeof(holder._relocbuf)) guarantee_size();
669 assert((void* const *)holder.reloc() == &holder._relocbuf[0], "ptrs must agree");
670 return holder.reloc();
671 }
672
673 // make a generic relocation for a given type (if possible)
674 static RelocationHolder spec_simple(relocInfo::relocType rtype);
675
676 // here is the type-specific hook which writes relocation data:
677 virtual void pack_data_to(CodeSection* dest) { }
678
679 // here is the type-specific hook which reads (unpacks) relocation data:
680 virtual void unpack_data() {
681 assert(datalen()==0 || type()==relocInfo::none, "no data here");
682 }
683
684 protected:
685 // Helper functions for pack_data_to() and unpack_data().
686
687 // Most of the compression logic is confined here.
688 // (The "immediate data" mechanism of relocInfo works independently
689 // of this stuff, and acts to further compress most 1-word data prefixes.)
690
691 // A variable-width int is encoded as a short if it will fit in 16 bits.
692 // The decoder looks at datalen to decide whether to unpack short or jint.
693 // Most relocation records are quite simple, containing at most two ints.
694
695 static bool is_short(jint x) { return x == (short)x; }
696 static short* add_short(short* p, int x) { *p++ = x; return p; }
697 static short* add_jint (short* p, jint x) {
698 *p++ = relocInfo::data0_from_int(x); *p++ = relocInfo::data1_from_int(x);
699 return p;
700 }
701 static short* add_var_int(short* p, jint x) { // add a variable-width int
702 if (is_short(x)) p = add_short(p, x);
703 else p = add_jint (p, x);
704 return p;
705 }
706
707 static short* pack_1_int_to(short* p, jint x0) {
708 // Format is one of: [] [x] [Xx]
709 if (x0 != 0) p = add_var_int(p, x0);
710 return p;
711 }
712 int unpack_1_int() {
713 assert(datalen() <= 2, "too much data");
714 return relocInfo::jint_data_at(0, data(), datalen());
715 }
716
717 // With two ints, the short form is used only if both ints are short.
718 short* pack_2_ints_to(short* p, jint x0, jint x1) {
719 // Format is one of: [] [x y?] [Xx Y?y]
720 if (x0 == 0 && x1 == 0) {
721 // no halfwords needed to store zeroes
722 } else if (is_short(x0) && is_short(x1)) {
723 // 1-2 halfwords needed to store shorts
724 p = add_short(p, x0); if (x1!=0) p = add_short(p, x1);
725 } else {
726 // 3-4 halfwords needed to store jints
727 p = add_jint(p, x0); p = add_var_int(p, x1);
728 }
729 return p;
730 }
731 void unpack_2_ints(jint& x0, jint& x1) {
732 int dlen = datalen();
733 short* dp = data();
734 if (dlen <= 2) {
735 x0 = relocInfo::short_data_at(0, dp, dlen);
736 x1 = relocInfo::short_data_at(1, dp, dlen);
737 } else {
738 assert(dlen <= 4, "too much data");
739 x0 = relocInfo::jint_data_at(0, dp, dlen);
740 x1 = relocInfo::jint_data_at(2, dp, dlen);
741 }
742 }
743
744 protected:
745 // platform-independent utility for patching constant section
746 void const_set_data_value (address x);
747 void const_verify_data_value (address x);
748 // platform-dependent utilities for decoding and patching instructions
749 void pd_set_data_value (address x, intptr_t off, bool verify_only = false); // a set or mem-ref
750 void pd_verify_data_value (address x, intptr_t off) { pd_set_data_value(x, off, true); }
751 address pd_call_destination (address orig_addr = NULL);
752 void pd_set_call_destination (address x);
753
754 // this extracts the address of an address in the code stream instead of the reloc data
755 address* pd_address_in_code ();
756
757 // this extracts an address from the code stream instead of the reloc data
758 address pd_get_address_from_code ();
759
760 // these convert from byte offsets, to scaled offsets, to addresses
761 static jint scaled_offset(address x, address base) {
762 int byte_offset = x - base;
763 int offset = -byte_offset / relocInfo::addr_unit();
764 assert(address_from_scaled_offset(offset, base) == x, "just checkin'");
765 return offset;
766 }
767 static jint scaled_offset_null_special(address x, address base) {
768 // Some relocations treat offset=0 as meaning NULL.
769 // Handle this extra convention carefully.
770 if (x == NULL) return 0;
771 assert(x != base, "offset must not be zero");
772 return scaled_offset(x, base);
773 }
774 static address address_from_scaled_offset(jint offset, address base) {
775 int byte_offset = -( offset * relocInfo::addr_unit() );
776 return base + byte_offset;
777 }
778
779 // helpers for mapping between old and new addresses after a move or resize
780 address old_addr_for(address newa, const CodeBuffer* src, CodeBuffer* dest);
781 address new_addr_for(address olda, const CodeBuffer* src, CodeBuffer* dest);
782 void normalize_address(address& addr, const CodeSection* dest, bool allow_other_sections = false);
783
784 public:
785 // accessors which only make sense for a bound Relocation
786 address addr() const { return binding()->addr(); }
787 CompiledMethod* code() const { return binding()->code(); }
788 bool addr_in_const() const { return binding()->addr_in_const(); }
789 protected:
790 short* data() const { return binding()->data(); }
791 int datalen() const { return binding()->datalen(); }
792 int format() const { return binding()->format(); }
793
794 public:
795 virtual relocInfo::relocType type() { return relocInfo::none; }
796
797 // is it a call instruction?
798 virtual bool is_call() { return false; }
799
800 // is it a data movement instruction?
801 virtual bool is_data() { return false; }
802
803 // some relocations can compute their own values
804 virtual address value();
805
806 // all relocations are able to reassert their values
807 virtual void set_value(address x);
808
809 virtual bool clear_inline_cache() { return true; }
810
811 // This method assumes that all virtual/static (inline) caches are cleared (since for static_call_type and
812 // ic_call_type is not always posisition dependent (depending on the state of the cache)). However, this is
813 // probably a reasonable assumption, since empty caches simplifies code reloacation.
814 virtual void fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest) { }
815};
816
817
818// certain inlines must be deferred until class Relocation is defined:
819
820inline RelocationHolder::RelocationHolder() {
821 // initialize the vtbl, just to keep things type-safe
822 new(*this) Relocation();
823}
824
825
826inline RelocationHolder::RelocationHolder(Relocation* r) {
827 // wordwise copy from r (ok if it copies garbage after r)
828 for (int i = 0; i < _relocbuf_size; i++) {
829 _relocbuf[i] = ((void**)r)[i];
830 }
831}
832
833
834relocInfo::relocType RelocationHolder::type() const {
835 return reloc()->type();
836}
837
838// A DataRelocation always points at a memory or load-constant instruction..
839// It is absolute on most machines, and the constant is split on RISCs.
840// The specific subtypes are oop, external_word, and internal_word.
841// By convention, the "value" does not include a separately reckoned "offset".
842class DataRelocation : public Relocation {
843 public:
844 bool is_data() { return true; }
845
846 // both target and offset must be computed somehow from relocation data
847 virtual int offset() { return 0; }
848 address value() = 0;
849 void set_value(address x) { set_value(x, offset()); }
850 void set_value(address x, intptr_t o) {
851 if (addr_in_const())
852 const_set_data_value(x);
853 else
854 pd_set_data_value(x, o);
855 }
856 void verify_value(address x) {
857 if (addr_in_const())
858 const_verify_data_value(x);
859 else
860 pd_verify_data_value(x, offset());
861 }
862
863 // The "o" (displacement) argument is relevant only to split relocations
864 // on RISC machines. In some CPUs (SPARC), the set-hi and set-lo ins'ns
865 // can encode more than 32 bits between them. This allows compilers to
866 // share set-hi instructions between addresses that differ by a small
867 // offset (e.g., different static variables in the same class).
868 // On such machines, the "x" argument to set_value on all set-lo
869 // instructions must be the same as the "x" argument for the
870 // corresponding set-hi instructions. The "o" arguments for the
871 // set-hi instructions are ignored, and must not affect the high-half
872 // immediate constant. The "o" arguments for the set-lo instructions are
873 // added into the low-half immediate constant, and must not overflow it.
874};
875
876// A CallRelocation always points at a call instruction.
877// It is PC-relative on most machines.
878class CallRelocation : public Relocation {
879 public:
880 bool is_call() { return true; }
881
882 address destination() { return pd_call_destination(); }
883 void set_destination(address x); // pd_set_call_destination
884
885 void fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest);
886 address value() { return destination(); }
887 void set_value(address x) { set_destination(x); }
888};
889
890class oop_Relocation : public DataRelocation {
891 relocInfo::relocType type() { return relocInfo::oop_type; }
892
893 public:
894 // encode in one of these formats: [] [n] [n l] [Nn l] [Nn Ll]
895 // an oop in the CodeBlob's oop pool
896 static RelocationHolder spec(int oop_index, int offset = 0) {
897 assert(oop_index > 0, "must be a pool-resident oop");
898 RelocationHolder rh = newHolder();
899 new(rh) oop_Relocation(oop_index, offset);
900 return rh;
901 }
902 // an oop in the instruction stream
903 static RelocationHolder spec_for_immediate() {
904 // If no immediate oops are generated, we can skip some walks over nmethods.
905 // Assert that they don't get generated accidently!
906 assert(relocInfo::mustIterateImmediateOopsInCode(),
907 "Must return true so we will search for oops as roots etc. in the code.");
908 const int oop_index = 0;
909 const int offset = 0; // if you want an offset, use the oop pool
910 RelocationHolder rh = newHolder();
911 new(rh) oop_Relocation(oop_index, offset);
912 return rh;
913 }
914
915 private:
916 jint _oop_index; // if > 0, index into CodeBlob::oop_at
917 jint _offset; // byte offset to apply to the oop itself
918
919 oop_Relocation(int oop_index, int offset) {
920 _oop_index = oop_index; _offset = offset;
921 }
922
923 friend class RelocIterator;
924 oop_Relocation() { }
925
926 public:
927 int oop_index() { return _oop_index; }
928 int offset() { return _offset; }
929
930 // data is packed in "2_ints" format: [i o] or [Ii Oo]
931 void pack_data_to(CodeSection* dest);
932 void unpack_data();
933
934 void fix_oop_relocation(); // reasserts oop value
935
936 void verify_oop_relocation();
937
938 address value() { return (address) *oop_addr(); }
939
940 bool oop_is_immediate() { return oop_index() == 0; }
941
942 oop* oop_addr(); // addr or &pool[jint_data]
943 oop oop_value(); // *oop_addr
944 // Note: oop_value transparently converts Universe::non_oop_word to NULL.
945};
946
947
948// copy of oop_Relocation for now but may delete stuff in both/either
949class metadata_Relocation : public DataRelocation {
950 relocInfo::relocType type() { return relocInfo::metadata_type; }
951
952 public:
953 // encode in one of these formats: [] [n] [n l] [Nn l] [Nn Ll]
954 // an metadata in the CodeBlob's metadata pool
955 static RelocationHolder spec(int metadata_index, int offset = 0) {
956 assert(metadata_index > 0, "must be a pool-resident metadata");
957 RelocationHolder rh = newHolder();
958 new(rh) metadata_Relocation(metadata_index, offset);
959 return rh;
960 }
961 // an metadata in the instruction stream
962 static RelocationHolder spec_for_immediate() {
963 const int metadata_index = 0;
964 const int offset = 0; // if you want an offset, use the metadata pool
965 RelocationHolder rh = newHolder();
966 new(rh) metadata_Relocation(metadata_index, offset);
967 return rh;
968 }
969
970 private:
971 jint _metadata_index; // if > 0, index into nmethod::metadata_at
972 jint _offset; // byte offset to apply to the metadata itself
973
974 metadata_Relocation(int metadata_index, int offset) {
975 _metadata_index = metadata_index; _offset = offset;
976 }
977
978 friend class RelocIterator;
979 metadata_Relocation() { }
980
981 // Fixes a Metadata pointer in the code. Most platforms embeds the
982 // Metadata pointer in the code at compile time so this is empty
983 // for them.
984 void pd_fix_value(address x);
985
986 public:
987 int metadata_index() { return _metadata_index; }
988 int offset() { return _offset; }
989
990 // data is packed in "2_ints" format: [i o] or [Ii Oo]
991 void pack_data_to(CodeSection* dest);
992 void unpack_data();
993
994 void fix_metadata_relocation(); // reasserts metadata value
995
996 address value() { return (address) *metadata_addr(); }
997
998 bool metadata_is_immediate() { return metadata_index() == 0; }
999
1000 Metadata** metadata_addr(); // addr or &pool[jint_data]
1001 Metadata* metadata_value(); // *metadata_addr
1002 // Note: metadata_value transparently converts Universe::non_metadata_word to NULL.
1003};
1004
1005
1006class virtual_call_Relocation : public CallRelocation {
1007 relocInfo::relocType type() { return relocInfo::virtual_call_type; }
1008
1009 public:
1010 // "cached_value" points to the first associated set-oop.
1011 // The oop_limit helps find the last associated set-oop.
1012 // (See comments at the top of this file.)
1013 static RelocationHolder spec(address cached_value, jint method_index = 0) {
1014 RelocationHolder rh = newHolder();
1015 new(rh) virtual_call_Relocation(cached_value, method_index);
1016 return rh;
1017 }
1018
1019 private:
1020 address _cached_value; // location of set-value instruction
1021 jint _method_index; // resolved method for a Java call
1022
1023 virtual_call_Relocation(address cached_value, int method_index) {
1024 _cached_value = cached_value;
1025 _method_index = method_index;
1026 assert(cached_value != NULL, "first oop address must be specified");
1027 }
1028
1029 friend class RelocIterator;
1030 virtual_call_Relocation() { }
1031
1032 public:
1033 address cached_value();
1034
1035 int method_index() { return _method_index; }
1036 Method* method_value();
1037
1038 // data is packed as scaled offsets in "2_ints" format: [f l] or [Ff Ll]
1039 // oop_limit is set to 0 if the limit falls somewhere within the call.
1040 // When unpacking, a zero oop_limit is taken to refer to the end of the call.
1041 // (This has the effect of bringing in the call's delay slot on SPARC.)
1042 void pack_data_to(CodeSection* dest);
1043 void unpack_data();
1044
1045 bool clear_inline_cache();
1046};
1047
1048
1049class opt_virtual_call_Relocation : public CallRelocation {
1050 relocInfo::relocType type() { return relocInfo::opt_virtual_call_type; }
1051
1052 public:
1053 static RelocationHolder spec(int method_index = 0) {
1054 RelocationHolder rh = newHolder();
1055 new(rh) opt_virtual_call_Relocation(method_index);
1056 return rh;
1057 }
1058
1059 private:
1060 jint _method_index; // resolved method for a Java call
1061
1062 opt_virtual_call_Relocation(int method_index) {
1063 _method_index = method_index;
1064 }
1065
1066 friend class RelocIterator;
1067 opt_virtual_call_Relocation() {}
1068
1069 public:
1070 int method_index() { return _method_index; }
1071 Method* method_value();
1072
1073 void pack_data_to(CodeSection* dest);
1074 void unpack_data();
1075
1076 bool clear_inline_cache();
1077
1078 // find the matching static_stub
1079 address static_stub(bool is_aot);
1080};
1081
1082
1083class static_call_Relocation : public CallRelocation {
1084 relocInfo::relocType type() { return relocInfo::static_call_type; }
1085
1086 public:
1087 static RelocationHolder spec(int method_index = 0) {
1088 RelocationHolder rh = newHolder();
1089 new(rh) static_call_Relocation(method_index);
1090 return rh;
1091 }
1092
1093 private:
1094 jint _method_index; // resolved method for a Java call
1095
1096 static_call_Relocation(int method_index) {
1097 _method_index = method_index;
1098 }
1099
1100 friend class RelocIterator;
1101 static_call_Relocation() {}
1102
1103 public:
1104 int method_index() { return _method_index; }
1105 Method* method_value();
1106
1107 void pack_data_to(CodeSection* dest);
1108 void unpack_data();
1109
1110 bool clear_inline_cache();
1111
1112 // find the matching static_stub
1113 address static_stub(bool is_aot);
1114};
1115
1116class static_stub_Relocation : public Relocation {
1117 relocInfo::relocType type() { return relocInfo::static_stub_type; }
1118
1119 public:
1120 static RelocationHolder spec(address static_call, bool is_aot = false) {
1121 RelocationHolder rh = newHolder();
1122 new(rh) static_stub_Relocation(static_call, is_aot);
1123 return rh;
1124 }
1125
1126 private:
1127 address _static_call; // location of corresponding static_call
1128 bool _is_aot; // trampoline to aot code
1129
1130 static_stub_Relocation(address static_call, bool is_aot) {
1131 _static_call = static_call;
1132 _is_aot = is_aot;
1133 }
1134
1135 friend class RelocIterator;
1136 static_stub_Relocation() { }
1137
1138 public:
1139 bool clear_inline_cache();
1140
1141 address static_call() { return _static_call; }
1142 bool is_aot() { return _is_aot; }
1143
1144 // data is packed as a scaled offset in "1_int" format: [c] or [Cc]
1145 void pack_data_to(CodeSection* dest);
1146 void unpack_data();
1147};
1148
1149class runtime_call_Relocation : public CallRelocation {
1150 relocInfo::relocType type() { return relocInfo::runtime_call_type; }
1151
1152 public:
1153 static RelocationHolder spec() {
1154 RelocationHolder rh = newHolder();
1155 new(rh) runtime_call_Relocation();
1156 return rh;
1157 }
1158
1159 private:
1160 friend class RelocIterator;
1161 runtime_call_Relocation() { }
1162
1163 public:
1164};
1165
1166
1167class runtime_call_w_cp_Relocation : public CallRelocation {
1168 relocInfo::relocType type() { return relocInfo::runtime_call_w_cp_type; }
1169
1170 public:
1171 static RelocationHolder spec() {
1172 RelocationHolder rh = newHolder();
1173 new(rh) runtime_call_w_cp_Relocation();
1174 return rh;
1175 }
1176
1177 private:
1178 friend class RelocIterator;
1179 runtime_call_w_cp_Relocation() { _offset = -4; /* <0 = invalid */ }
1180 // On z/Architecture, runtime calls are either a sequence
1181 // of two instructions (load destination of call from constant pool + do call)
1182 // or a pc-relative call. The pc-relative call is faster, but it can only
1183 // be used if the destination of the call is not too far away.
1184 // In order to be able to patch a pc-relative call back into one using
1185 // the constant pool, we have to remember the location of the call's destination
1186 // in the constant pool.
1187 int _offset;
1188
1189 public:
1190 void set_constant_pool_offset(int offset) { _offset = offset; }
1191 int get_constant_pool_offset() { return _offset; }
1192 void pack_data_to(CodeSection * dest);
1193 void unpack_data();
1194};
1195
1196// Trampoline Relocations.
1197// A trampoline allows to encode a small branch in the code, even if there
1198// is the chance that this branch can not reach all possible code locations.
1199// If the relocation finds that a branch is too far for the instruction
1200// in the code, it can patch it to jump to the trampoline where is
1201// sufficient space for a far branch. Needed on PPC.
1202class trampoline_stub_Relocation : public Relocation {
1203 relocInfo::relocType type() { return relocInfo::trampoline_stub_type; }
1204
1205 public:
1206 static RelocationHolder spec(address static_call) {
1207 RelocationHolder rh = newHolder();
1208 return (new (rh) trampoline_stub_Relocation(static_call));
1209 }
1210
1211 private:
1212 address _owner; // Address of the NativeCall that owns the trampoline.
1213
1214 trampoline_stub_Relocation(address owner) {
1215 _owner = owner;
1216 }
1217
1218 friend class RelocIterator;
1219 trampoline_stub_Relocation() { }
1220
1221 public:
1222
1223 // Return the address of the NativeCall that owns the trampoline.
1224 address owner() { return _owner; }
1225
1226 void pack_data_to(CodeSection * dest);
1227 void unpack_data();
1228
1229 // Find the trampoline stub for a call.
1230 static address get_trampoline_for(address call, nmethod* code);
1231};
1232
1233class external_word_Relocation : public DataRelocation {
1234 relocInfo::relocType type() { return relocInfo::external_word_type; }
1235
1236 public:
1237 static RelocationHolder spec(address target) {
1238 assert(target != NULL, "must not be null");
1239 RelocationHolder rh = newHolder();
1240 new(rh) external_word_Relocation(target);
1241 return rh;
1242 }
1243
1244 // Use this one where all 32/64 bits of the target live in the code stream.
1245 // The target must be an intptr_t, and must be absolute (not relative).
1246 static RelocationHolder spec_for_immediate() {
1247 RelocationHolder rh = newHolder();
1248 new(rh) external_word_Relocation(NULL);
1249 return rh;
1250 }
1251
1252 // Some address looking values aren't safe to treat as relocations
1253 // and should just be treated as constants.
1254 static bool can_be_relocated(address target) {
1255 assert(target == NULL || (uintptr_t)target >= (uintptr_t)os::vm_page_size(), INTPTR_FORMAT, (intptr_t)target);
1256 return target != NULL;
1257 }
1258
1259 private:
1260 address _target; // address in runtime
1261
1262 external_word_Relocation(address target) {
1263 _target = target;
1264 }
1265
1266 friend class RelocIterator;
1267 external_word_Relocation() { }
1268
1269 public:
1270 // data is packed as a well-known address in "1_int" format: [a] or [Aa]
1271 // The function runtime_address_to_index is used to turn full addresses
1272 // to short indexes, if they are pre-registered by the stub mechanism.
1273 // If the "a" value is 0 (i.e., _target is NULL), the address is stored
1274 // in the code stream. See external_word_Relocation::target().
1275 void pack_data_to(CodeSection* dest);
1276 void unpack_data();
1277
1278 void fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest);
1279 address target(); // if _target==NULL, fetch addr from code stream
1280 address value() { return target(); }
1281};
1282
1283class internal_word_Relocation : public DataRelocation {
1284 relocInfo::relocType type() { return relocInfo::internal_word_type; }
1285
1286 public:
1287 static RelocationHolder spec(address target) {
1288 assert(target != NULL, "must not be null");
1289 RelocationHolder rh = newHolder();
1290 new(rh) internal_word_Relocation(target);
1291 return rh;
1292 }
1293
1294 // use this one where all the bits of the target can fit in the code stream:
1295 static RelocationHolder spec_for_immediate() {
1296 RelocationHolder rh = newHolder();
1297 new(rh) internal_word_Relocation(NULL);
1298 return rh;
1299 }
1300
1301 internal_word_Relocation(address target) {
1302 _target = target;
1303 _section = -1; // self-relative
1304 }
1305
1306 protected:
1307 address _target; // address in CodeBlob
1308 int _section; // section providing base address, if any
1309
1310 friend class RelocIterator;
1311 internal_word_Relocation() { }
1312
1313 // bit-width of LSB field in packed offset, if section >= 0
1314 enum { section_width = 2 }; // must equal CodeBuffer::sect_bits
1315
1316 public:
1317 // data is packed as a scaled offset in "1_int" format: [o] or [Oo]
1318 // If the "o" value is 0 (i.e., _target is NULL), the offset is stored
1319 // in the code stream. See internal_word_Relocation::target().
1320 // If _section is not -1, it is appended to the low bits of the offset.
1321 void pack_data_to(CodeSection* dest);
1322 void unpack_data();
1323
1324 void fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest);
1325 address target(); // if _target==NULL, fetch addr from code stream
1326 int section() { return _section; }
1327 address value() { return target(); }
1328};
1329
1330class section_word_Relocation : public internal_word_Relocation {
1331 relocInfo::relocType type() { return relocInfo::section_word_type; }
1332
1333 public:
1334 static RelocationHolder spec(address target, int section) {
1335 RelocationHolder rh = newHolder();
1336 new(rh) section_word_Relocation(target, section);
1337 return rh;
1338 }
1339
1340 section_word_Relocation(address target, int section) {
1341 assert(target != NULL, "must not be null");
1342 assert(section >= 0, "must be a valid section");
1343 _target = target;
1344 _section = section;
1345 }
1346
1347 //void pack_data_to -- inherited
1348 void unpack_data();
1349
1350 private:
1351 friend class RelocIterator;
1352 section_word_Relocation() { }
1353};
1354
1355
1356class poll_Relocation : public Relocation {
1357 bool is_data() { return true; }
1358 relocInfo::relocType type() { return relocInfo::poll_type; }
1359 void fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest);
1360};
1361
1362class poll_return_Relocation : public poll_Relocation {
1363 relocInfo::relocType type() { return relocInfo::poll_return_type; }
1364};
1365
1366// We know all the xxx_Relocation classes, so now we can define these:
1367#define EACH_CASE(name) \
1368inline name##_Relocation* RelocIterator::name##_reloc() { \
1369 assert(type() == relocInfo::name##_type, "type must agree"); \
1370 /* The purpose of the placed "new" is to re-use the same */ \
1371 /* stack storage for each new iteration. */ \
1372 name##_Relocation* r = new(_rh) name##_Relocation(); \
1373 r->set_binding(this); \
1374 r->name##_Relocation::unpack_data(); \
1375 return r; \
1376}
1377APPLY_TO_RELOCATIONS(EACH_CASE);
1378#undef EACH_CASE
1379
1380inline RelocIterator::RelocIterator(CompiledMethod* nm, address begin, address limit) {
1381 initialize(nm, begin, limit);
1382}
1383
1384#endif // SHARE_CODE_RELOCINFO_HPP
1385