1 /*
2 * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
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7 * published by the Free Software Foundation.
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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
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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 #ifdef TARGET_ARCH_aarch64
434 # include "relocInfo_aarch64.hpp"
435 #endif
436
437 protected:
438 // Derived constant, based on format_width which is PD:
439 enum {
440 offset_width = nontype_width - format_width,
441 offset_mask = (1<<offset_width) - 1,
442 format_mask = (1<<format_width) - 1
443 };
444 public:
445 enum {
446 // Conservatively large estimate of maximum length (in shorts)
447 // of any relocation record.
448 // Extended format is length prefix, data words, and tag/offset suffix.
449 length_limit = 1 + 1 + (3*BytesPerWord/BytesPerShort) + 1,
450 have_format = format_width > 0
451 };
452 };
453
454 #define FORWARD_DECLARE_EACH_CLASS(name) \
455 class name##_Relocation;
456 APPLY_TO_RELOCATIONS(FORWARD_DECLARE_EACH_CLASS)
457 #undef FORWARD_DECLARE_EACH_CLASS
458
459
460
461 inline relocInfo filler_relocInfo() {
462 return relocInfo(relocInfo::none, relocInfo::offset_limit() - relocInfo::offset_unit);
463 }
464
465 inline relocInfo prefix_relocInfo(int datalen = 0) {
466 assert(relocInfo::fits_into_immediate(datalen), "datalen in limits");
467 return relocInfo(relocInfo::data_prefix_tag, relocInfo::RAW_BITS, relocInfo::datalen_tag | datalen);
468 }
469
470
471 // Holder for flyweight relocation objects.
472 // Although the flyweight subclasses are of varying sizes,
473 // the holder is "one size fits all".
474 class RelocationHolder VALUE_OBJ_CLASS_SPEC {
475 friend class Relocation;
476 friend class CodeSection;
477
478 private:
479 // this preallocated memory must accommodate all subclasses of Relocation
480 // (this number is assertion-checked in Relocation::operator new)
481 enum { _relocbuf_size = 5 };
482 void* _relocbuf[ _relocbuf_size ];
483
484 public:
485 Relocation* reloc() const { return (Relocation*) &_relocbuf[0]; }
486 inline relocInfo::relocType type() const;
487
488 // Add a constant offset to a relocation. Helper for class Address.
489 RelocationHolder plus(int offset) const;
490
491 inline RelocationHolder(); // initializes type to none
492
493 inline RelocationHolder(Relocation* r); // make a copy
494
495 static const RelocationHolder none;
496 };
497
498 // A RelocIterator iterates through the relocation information of a CodeBlob.
499 // It is a variable BoundRelocation which is able to take on successive
500 // values as it is advanced through a code stream.
501 // Usage:
502 // RelocIterator iter(nm);
503 // while (iter.next()) {
504 // iter.reloc()->some_operation();
505 // }
506 // or:
507 // RelocIterator iter(nm);
508 // while (iter.next()) {
509 // switch (iter.type()) {
510 // case relocInfo::oop_type :
511 // case relocInfo::ic_type :
512 // case relocInfo::prim_type :
513 // case relocInfo::uncommon_type :
514 // case relocInfo::runtime_call_type :
515 // case relocInfo::internal_word_type:
516 // case relocInfo::external_word_type:
517 // ...
518 // }
519 // }
520
521 class RelocIterator : public StackObj {
522 enum { SECT_LIMIT = 3 }; // must be equal to CodeBuffer::SECT_LIMIT, checked in ctor
523 friend class Relocation;
524 friend class relocInfo; // for change_reloc_info_for_address only
525 typedef relocInfo::relocType relocType;
526
527 private:
528 address _limit; // stop producing relocations after this _addr
529 relocInfo* _current; // the current relocation information
530 relocInfo* _end; // end marker; we're done iterating when _current == _end
531 nmethod* _code; // compiled method containing _addr
532 address _addr; // instruction to which the relocation applies
533 short _databuf; // spare buffer for compressed data
534 short* _data; // pointer to the relocation's data
535 short _datalen; // number of halfwords in _data
536 char _format; // position within the instruction
537
538 // Base addresses needed to compute targets of section_word_type relocs.
539 address _section_start[SECT_LIMIT];
540 address _section_end [SECT_LIMIT];
541
542 void set_has_current(bool b) {
543 _datalen = !b ? -1 : 0;
544 debug_only(_data = NULL);
545 }
546 void set_current(relocInfo& ri) {
547 _current = &ri;
548 set_has_current(true);
549 }
550
551 RelocationHolder _rh; // where the current relocation is allocated
552
553 relocInfo* current() const { assert(has_current(), "must have current");
554 return _current; }
555
556 void set_limits(address begin, address limit);
557
558 void advance_over_prefix(); // helper method
559
560 void initialize_misc();
561
562 void initialize(nmethod* nm, address begin, address limit);
563
564 RelocIterator() { initialize_misc(); }
565
566 public:
567 // constructor
568 RelocIterator(nmethod* nm, address begin = NULL, address limit = NULL);
569 RelocIterator(CodeSection* cb, address begin = NULL, address limit = NULL);
570
571 // get next reloc info, return !eos
572 bool next() {
573 _current++;
574 assert(_current <= _end, "must not overrun relocInfo");
575 if (_current == _end) {
576 set_has_current(false);
577 return false;
578 }
579 set_has_current(true);
580
581 if (_current->is_prefix()) {
582 advance_over_prefix();
583 assert(!current()->is_prefix(), "only one prefix at a time");
584 }
585
586 _addr += _current->addr_offset();
587
588 if (_limit != NULL && _addr >= _limit) {
589 set_has_current(false);
590 return false;
591 }
592
593 if (relocInfo::have_format) _format = current()->format();
594 return true;
595 }
596
597 // accessors
598 address limit() const { return _limit; }
599 void set_limit(address x);
600 relocType type() const { return current()->type(); }
601 int format() const { return (relocInfo::have_format) ? current()->format() : 0; }
602 address addr() const { return _addr; }
603 nmethod* code() const { return _code; }
604 short* data() const { return _data; }
605 int datalen() const { return _datalen; }
606 bool has_current() const { return _datalen >= 0; }
607
608 void set_addr(address addr) { _addr = addr; }
609 bool addr_in_const() const;
610
611 address section_start(int n) const {
612 assert(_section_start[n], "must be initialized");
613 return _section_start[n];
614 }
615 address section_end(int n) const {
616 assert(_section_end[n], "must be initialized");
617 return _section_end[n];
618 }
619
620 // The address points to the affected displacement part of the instruction.
621 // For RISC, this is just the whole instruction.
622 // For Intel, this is an unaligned 32-bit word.
623
624 // type-specific relocation accessors: oop_Relocation* oop_reloc(), etc.
625 #define EACH_TYPE(name) \
626 inline name##_Relocation* name##_reloc();
627 APPLY_TO_RELOCATIONS(EACH_TYPE)
628 #undef EACH_TYPE
629 // generic relocation accessor; switches on type to call the above
630 Relocation* reloc();
631
632 // CodeBlob's have relocation indexes for faster random access:
633 static int locs_and_index_size(int code_size, int locs_size);
634 // Store an index into [dest_start+dest_count..dest_end).
635 // At dest_start[0..dest_count] is the actual relocation information.
636 // Everything else up to dest_end is free space for the index.
637 static void create_index(relocInfo* dest_begin, int dest_count, relocInfo* dest_end);
638
639 #ifndef PRODUCT
640 public:
641 void print();
642 void print_current();
643 #endif
644 };
645
646
647 // A Relocation is a flyweight object allocated within a RelocationHolder.
648 // It represents the relocation data of relocation record.
649 // So, the RelocIterator unpacks relocInfos into Relocations.
650
651 class Relocation VALUE_OBJ_CLASS_SPEC {
652 friend class RelocationHolder;
653 friend class RelocIterator;
654
655 private:
656 static void guarantee_size();
657
658 // When a relocation has been created by a RelocIterator,
659 // this field is non-null. It allows the relocation to know
660 // its context, such as the address to which it applies.
661 RelocIterator* _binding;
662
663 protected:
664 RelocIterator* binding() const {
665 assert(_binding != NULL, "must be bound");
666 return _binding;
667 }
668 void set_binding(RelocIterator* b) {
669 assert(_binding == NULL, "must be unbound");
670 _binding = b;
671 assert(_binding != NULL, "must now be bound");
672 }
673
674 Relocation() {
675 _binding = NULL;
676 }
677
678 static RelocationHolder newHolder() {
679 return RelocationHolder();
680 }
681
682 public:
683 void* operator new(size_t size, const RelocationHolder& holder) throw() {
684 if (size > sizeof(holder._relocbuf)) guarantee_size();
685 assert((void* const *)holder.reloc() == &holder._relocbuf[0], "ptrs must agree");
686 return holder.reloc();
687 }
688
689 // make a generic relocation for a given type (if possible)
690 static RelocationHolder spec_simple(relocInfo::relocType rtype);
691
692 // here is the type-specific hook which writes relocation data:
693 virtual void pack_data_to(CodeSection* dest) { }
694
695 // here is the type-specific hook which reads (unpacks) relocation data:
696 virtual void unpack_data() {
697 assert(datalen()==0 || type()==relocInfo::none, "no data here");
698 }
699
700 static bool is_reloc_index(intptr_t index) {
701 return 0 < index && index < os::vm_page_size();
702 }
703
704 protected:
705 // Helper functions for pack_data_to() and unpack_data().
706
707 // Most of the compression logic is confined here.
708 // (The "immediate data" mechanism of relocInfo works independently
709 // of this stuff, and acts to further compress most 1-word data prefixes.)
710
711 // A variable-width int is encoded as a short if it will fit in 16 bits.
712 // The decoder looks at datalen to decide whether to unpack short or jint.
713 // Most relocation records are quite simple, containing at most two ints.
714
715 static bool is_short(jint x) { return x == (short)x; }
716 static short* add_short(short* p, int x) { *p++ = x; return p; }
717 static short* add_jint (short* p, jint x) {
718 *p++ = relocInfo::data0_from_int(x); *p++ = relocInfo::data1_from_int(x);
719 return p;
720 }
721 static short* add_var_int(short* p, jint x) { // add a variable-width int
722 if (is_short(x)) p = add_short(p, x);
723 else p = add_jint (p, x);
724 return p;
725 }
726
727 static short* pack_1_int_to(short* p, jint x0) {
728 // Format is one of: [] [x] [Xx]
729 if (x0 != 0) p = add_var_int(p, x0);
730 return p;
731 }
732 int unpack_1_int() {
733 assert(datalen() <= 2, "too much data");
734 return relocInfo::jint_data_at(0, data(), datalen());
735 }
736
737 // With two ints, the short form is used only if both ints are short.
738 short* pack_2_ints_to(short* p, jint x0, jint x1) {
739 // Format is one of: [] [x y?] [Xx Y?y]
740 if (x0 == 0 && x1 == 0) {
741 // no halfwords needed to store zeroes
742 } else if (is_short(x0) && is_short(x1)) {
743 // 1-2 halfwords needed to store shorts
744 p = add_short(p, x0); if (x1!=0) p = add_short(p, x1);
745 } else {
746 // 3-4 halfwords needed to store jints
747 p = add_jint(p, x0); p = add_var_int(p, x1);
748 }
749 return p;
750 }
751 void unpack_2_ints(jint& x0, jint& x1) {
752 int dlen = datalen();
753 short* dp = data();
754 if (dlen <= 2) {
755 x0 = relocInfo::short_data_at(0, dp, dlen);
756 x1 = relocInfo::short_data_at(1, dp, dlen);
757 } else {
758 assert(dlen <= 4, "too much data");
759 x0 = relocInfo::jint_data_at(0, dp, dlen);
760 x1 = relocInfo::jint_data_at(2, dp, dlen);
761 }
762 }
763
764 protected:
765 // platform-dependent utilities for decoding and patching instructions
766 void pd_set_data_value (address x, intptr_t off, bool verify_only = false); // a set or mem-ref
767 void pd_verify_data_value (address x, intptr_t off) { pd_set_data_value(x, off, true); }
768 address pd_call_destination (address orig_addr = NULL);
769 void pd_set_call_destination (address x);
770
771 // this extracts the address of an address in the code stream instead of the reloc data
772 address* pd_address_in_code ();
773
774 // this extracts an address from the code stream instead of the reloc data
775 address pd_get_address_from_code ();
776
777 // these convert from byte offsets, to scaled offsets, to addresses
778 static jint scaled_offset(address x, address base) {
779 int byte_offset = x - base;
780 int offset = -byte_offset / relocInfo::addr_unit();
781 assert(address_from_scaled_offset(offset, base) == x, "just checkin'");
782 return offset;
783 }
784 static jint scaled_offset_null_special(address x, address base) {
785 // Some relocations treat offset=0 as meaning NULL.
786 // Handle this extra convention carefully.
787 if (x == NULL) return 0;
788 assert(x != base, "offset must not be zero");
789 return scaled_offset(x, base);
790 }
791 static address address_from_scaled_offset(jint offset, address base) {
792 int byte_offset = -( offset * relocInfo::addr_unit() );
793 return base + byte_offset;
794 }
795
796 // these convert between indexes and addresses in the runtime system
797 static int32_t runtime_address_to_index(address runtime_address);
798 static address index_to_runtime_address(int32_t index);
799
800 // helpers for mapping between old and new addresses after a move or resize
801 address old_addr_for(address newa, const CodeBuffer* src, CodeBuffer* dest);
802 address new_addr_for(address olda, const CodeBuffer* src, CodeBuffer* dest);
803 void normalize_address(address& addr, const CodeSection* dest, bool allow_other_sections = false);
804
805 public:
806 // accessors which only make sense for a bound Relocation
807 address addr() const { return binding()->addr(); }
808 nmethod* code() const { return binding()->code(); }
809 bool addr_in_const() const { return binding()->addr_in_const(); }
810 protected:
811 short* data() const { return binding()->data(); }
812 int datalen() const { return binding()->datalen(); }
813 int format() const { return binding()->format(); }
814
815 public:
816 virtual relocInfo::relocType type() { return relocInfo::none; }
817
818 // is it a call instruction?
819 virtual bool is_call() { return false; }
820
821 // is it a data movement instruction?
822 virtual bool is_data() { return false; }
823
824 // some relocations can compute their own values
825 virtual address value();
826
827 // all relocations are able to reassert their values
828 virtual void set_value(address x);
829
830 virtual void clear_inline_cache() { }
831
832 // This method assumes that all virtual/static (inline) caches are cleared (since for static_call_type and
833 // ic_call_type is not always posisition dependent (depending on the state of the cache)). However, this is
834 // probably a reasonable assumption, since empty caches simplifies code reloacation.
835 virtual void fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest) { }
836
837 void print();
838 };
839
840
841 // certain inlines must be deferred until class Relocation is defined:
842
843 inline RelocationHolder::RelocationHolder() {
844 // initialize the vtbl, just to keep things type-safe
845 new(*this) Relocation();
846 }
847
848
849 inline RelocationHolder::RelocationHolder(Relocation* r) {
850 // wordwise copy from r (ok if it copies garbage after r)
851 for (int i = 0; i < _relocbuf_size; i++) {
852 _relocbuf[i] = ((void**)r)[i];
853 }
854 }
855
856
857 relocInfo::relocType RelocationHolder::type() const {
858 return reloc()->type();
859 }
860
861 // A DataRelocation always points at a memory or load-constant instruction..
862 // It is absolute on most machines, and the constant is split on RISCs.
863 // The specific subtypes are oop, external_word, and internal_word.
864 // By convention, the "value" does not include a separately reckoned "offset".
865 class DataRelocation : public Relocation {
866 public:
867 bool is_data() { return true; }
868
869 // both target and offset must be computed somehow from relocation data
870 virtual int offset() { return 0; }
871 address value() = 0;
872 void set_value(address x) { set_value(x, offset()); }
873 void set_value(address x, intptr_t o) {
874 if (addr_in_const())
875 *(address*)addr() = x;
876 else
877 pd_set_data_value(x, o);
878 }
879 void verify_value(address x) {
880 if (addr_in_const())
881 assert(*(address*)addr() == x, "must agree");
882 else
883 pd_verify_data_value(x, offset());
884 }
885
886 // The "o" (displacement) argument is relevant only to split relocations
887 // on RISC machines. In some CPUs (SPARC), the set-hi and set-lo ins'ns
888 // can encode more than 32 bits between them. This allows compilers to
889 // share set-hi instructions between addresses that differ by a small
890 // offset (e.g., different static variables in the same class).
891 // On such machines, the "x" argument to set_value on all set-lo
892 // instructions must be the same as the "x" argument for the
893 // corresponding set-hi instructions. The "o" arguments for the
894 // set-hi instructions are ignored, and must not affect the high-half
895 // immediate constant. The "o" arguments for the set-lo instructions are
896 // added into the low-half immediate constant, and must not overflow it.
897 };
898
899 // A CallRelocation always points at a call instruction.
900 // It is PC-relative on most machines.
901 class CallRelocation : public Relocation {
902 public:
903 bool is_call() { return true; }
904
905 address destination() { return pd_call_destination(); }
906 void set_destination(address x); // pd_set_call_destination
907
908 void fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest);
909 address value() { return destination(); }
910 void set_value(address x) { set_destination(x); }
911 };
912
913 class oop_Relocation : public DataRelocation {
914 relocInfo::relocType type() { return relocInfo::oop_type; }
915
916 public:
917 // encode in one of these formats: [] [n] [n l] [Nn l] [Nn Ll]
918 // an oop in the CodeBlob's oop pool
919 static RelocationHolder spec(int oop_index, int offset = 0) {
920 assert(oop_index > 0, "must be a pool-resident oop");
921 RelocationHolder rh = newHolder();
922 new(rh) oop_Relocation(oop_index, offset);
923 return rh;
924 }
925 // an oop in the instruction stream
926 static RelocationHolder spec_for_immediate() {
927 const int oop_index = 0;
928 const int offset = 0; // if you want an offset, use the oop pool
929 RelocationHolder rh = newHolder();
930 new(rh) oop_Relocation(oop_index, offset);
931 return rh;
932 }
933
934 private:
935 jint _oop_index; // if > 0, index into CodeBlob::oop_at
936 jint _offset; // byte offset to apply to the oop itself
937
938 oop_Relocation(int oop_index, int offset) {
939 _oop_index = oop_index; _offset = offset;
940 }
941
942 friend class RelocIterator;
943 oop_Relocation() { }
944
945 public:
946 int oop_index() { return _oop_index; }
947 int offset() { return _offset; }
948
949 // data is packed in "2_ints" format: [i o] or [Ii Oo]
950 void pack_data_to(CodeSection* dest);
951 void unpack_data();
952
953 void fix_oop_relocation(); // reasserts oop value
954
955 void verify_oop_relocation();
956
957 address value() { return (address) *oop_addr(); }
958
959 bool oop_is_immediate() { return oop_index() == 0; }
960
961 oop* oop_addr(); // addr or &pool[jint_data]
962 oop oop_value(); // *oop_addr
963 // Note: oop_value transparently converts Universe::non_oop_word to NULL.
964 };
965
966
967 // copy of oop_Relocation for now but may delete stuff in both/either
968 class metadata_Relocation : public DataRelocation {
969 relocInfo::relocType type() { return relocInfo::metadata_type; }
970
971 public:
972 // encode in one of these formats: [] [n] [n l] [Nn l] [Nn Ll]
973 // an metadata in the CodeBlob's metadata pool
974 static RelocationHolder spec(int metadata_index, int offset = 0) {
975 assert(metadata_index > 0, "must be a pool-resident metadata");
976 RelocationHolder rh = newHolder();
977 new(rh) metadata_Relocation(metadata_index, offset);
978 return rh;
979 }
980 // an metadata in the instruction stream
981 static RelocationHolder spec_for_immediate() {
982 const int metadata_index = 0;
983 const int offset = 0; // if you want an offset, use the metadata pool
984 RelocationHolder rh = newHolder();
985 new(rh) metadata_Relocation(metadata_index, offset);
986 return rh;
987 }
988
989 private:
990 jint _metadata_index; // if > 0, index into nmethod::metadata_at
991 jint _offset; // byte offset to apply to the metadata itself
992
993 metadata_Relocation(int metadata_index, int offset) {
994 _metadata_index = metadata_index; _offset = offset;
995 }
996
997 friend class RelocIterator;
998 metadata_Relocation() { }
999
1000 // Fixes a Metadata pointer in the code. Most platforms embeds the
1001 // Metadata pointer in the code at compile time so this is empty
1002 // for them.
1003 void pd_fix_value(address x);
1004
1005 public:
1006 int metadata_index() { return _metadata_index; }
1007 int offset() { return _offset; }
1008
1009 // data is packed in "2_ints" format: [i o] or [Ii Oo]
1010 void pack_data_to(CodeSection* dest);
1011 void unpack_data();
1012
1013 void fix_metadata_relocation(); // reasserts metadata value
1014
1015 void verify_metadata_relocation();
1016
1017 address value() { return (address) *metadata_addr(); }
1018
1019 bool metadata_is_immediate() { return metadata_index() == 0; }
1020
1021 Metadata** metadata_addr(); // addr or &pool[jint_data]
1022 Metadata* metadata_value(); // *metadata_addr
1023 // Note: metadata_value transparently converts Universe::non_metadata_word to NULL.
1024 };
1025
1026
1027 class virtual_call_Relocation : public CallRelocation {
1028 relocInfo::relocType type() { return relocInfo::virtual_call_type; }
1029
1030 public:
1031 // "cached_value" points to the first associated set-oop.
1032 // The oop_limit helps find the last associated set-oop.
1033 // (See comments at the top of this file.)
1034 static RelocationHolder spec(address cached_value) {
1035 RelocationHolder rh = newHolder();
1036 new(rh) virtual_call_Relocation(cached_value);
1037 return rh;
1038 }
1039
1040 virtual_call_Relocation(address cached_value) {
1041 _cached_value = cached_value;
1042 assert(cached_value != NULL, "first oop address must be specified");
1043 }
1044
1045 private:
1046 address _cached_value; // location of set-value instruction
1047
1048 friend class RelocIterator;
1049 virtual_call_Relocation() { }
1050
1051
1052 public:
1053 address cached_value();
1054
1055 // data is packed as scaled offsets in "2_ints" format: [f l] or [Ff Ll]
1056 // oop_limit is set to 0 if the limit falls somewhere within the call.
1057 // When unpacking, a zero oop_limit is taken to refer to the end of the call.
1058 // (This has the effect of bringing in the call's delay slot on SPARC.)
1059 void pack_data_to(CodeSection* dest);
1060 void unpack_data();
1061
1062 void clear_inline_cache();
1063 };
1064
1065
1066 class opt_virtual_call_Relocation : public CallRelocation {
1067 relocInfo::relocType type() { return relocInfo::opt_virtual_call_type; }
1068
1069 public:
1070 static RelocationHolder spec() {
1071 RelocationHolder rh = newHolder();
1072 new(rh) opt_virtual_call_Relocation();
1073 return rh;
1074 }
1075
1076 private:
1077 friend class RelocIterator;
1078 opt_virtual_call_Relocation() { }
1079
1080 public:
1081 void clear_inline_cache();
1082
1083 // find the matching static_stub
1084 address static_stub();
1085 };
1086
1087
1088 class static_call_Relocation : public CallRelocation {
1089 relocInfo::relocType type() { return relocInfo::static_call_type; }
1090
1091 public:
1092 static RelocationHolder spec() {
1093 RelocationHolder rh = newHolder();
1094 new(rh) static_call_Relocation();
1095 return rh;
1096 }
1097
1098 private:
1099 friend class RelocIterator;
1100 static_call_Relocation() { }
1101
1102 public:
1103 void clear_inline_cache();
1104
1105 // find the matching static_stub
1106 address static_stub();
1107 };
1108
1109 class static_stub_Relocation : public Relocation {
1110 relocInfo::relocType type() { return relocInfo::static_stub_type; }
1111
1112 public:
1113 static RelocationHolder spec(address static_call) {
1114 RelocationHolder rh = newHolder();
1115 new(rh) static_stub_Relocation(static_call);
1116 return rh;
1117 }
1118
1119 private:
1120 address _static_call; // location of corresponding static_call
1121
1122 static_stub_Relocation(address static_call) {
1123 _static_call = static_call;
1124 }
1125
1126 friend class RelocIterator;
1127 static_stub_Relocation() { }
1128
1129 public:
1130 void clear_inline_cache();
1131
1132 address static_call() { return _static_call; }
1133
1134 // data is packed as a scaled offset in "1_int" format: [c] or [Cc]
1135 void pack_data_to(CodeSection* dest);
1136 void unpack_data();
1137 };
1138
1139 class runtime_call_Relocation : public CallRelocation {
1140 relocInfo::relocType type() { return relocInfo::runtime_call_type; }
1141
1142 public:
1143 static RelocationHolder spec() {
1144 RelocationHolder rh = newHolder();
1145 new(rh) runtime_call_Relocation();
1146 return rh;
1147 }
1148
1149 private:
1150 friend class RelocIterator;
1151 runtime_call_Relocation() { }
1152
1153 public:
1154 };
1155
1156 // Trampoline Relocations.
1157 // A trampoline allows to encode a small branch in the code, even if there
1158 // is the chance that this branch can not reach all possible code locations.
1159 // If the relocation finds that a branch is too far for the instruction
1160 // in the code, it can patch it to jump to the trampoline where is
1161 // sufficient space for a far branch. Needed on PPC.
1162 class trampoline_stub_Relocation : public Relocation {
1163 relocInfo::relocType type() { return relocInfo::trampoline_stub_type; }
1164
1165 public:
1166 static RelocationHolder spec(address static_call) {
1167 RelocationHolder rh = newHolder();
1168 return (new (rh) trampoline_stub_Relocation(static_call));
1169 }
1170
1171 private:
1172 address _owner; // Address of the NativeCall that owns the trampoline.
1173
1174 trampoline_stub_Relocation(address owner) {
1175 _owner = owner;
1176 }
1177
1178 friend class RelocIterator;
1179 trampoline_stub_Relocation() { }
1180
1181 public:
1182
1183 // Return the address of the NativeCall that owns the trampoline.
1184 address owner() { return _owner; }
1185
1186 void pack_data_to(CodeSection * dest);
1187 void unpack_data();
1188
1189 // Find the trampoline stub for a call.
1190 static address get_trampoline_for(address call, nmethod* code);
1191 };
1192
1193 class external_word_Relocation : public DataRelocation {
1194 relocInfo::relocType type() { return relocInfo::external_word_type; }
1195
1196 public:
1197 static RelocationHolder spec(address target) {
1198 assert(target != NULL, "must not be null");
1199 RelocationHolder rh = newHolder();
1200 new(rh) external_word_Relocation(target);
1201 return rh;
1202 }
1203
1204 // Use this one where all 32/64 bits of the target live in the code stream.
1205 // The target must be an intptr_t, and must be absolute (not relative).
1206 static RelocationHolder spec_for_immediate() {
1207 RelocationHolder rh = newHolder();
1208 new(rh) external_word_Relocation(NULL);
1209 return rh;
1210 }
1211
1212 // Some address looking values aren't safe to treat as relocations
1213 // and should just be treated as constants.
1214 static bool can_be_relocated(address target) {
1215 return target != NULL && !is_reloc_index((intptr_t)target);
1216 }
1217
1218 private:
1219 address _target; // address in runtime
1220
1221 external_word_Relocation(address target) {
1222 _target = target;
1223 }
1224
1225 friend class RelocIterator;
1226 external_word_Relocation() { }
1227
1228 public:
1229 // data is packed as a well-known address in "1_int" format: [a] or [Aa]
1230 // The function runtime_address_to_index is used to turn full addresses
1231 // to short indexes, if they are pre-registered by the stub mechanism.
1232 // If the "a" value is 0 (i.e., _target is NULL), the address is stored
1233 // in the code stream. See external_word_Relocation::target().
1234 void pack_data_to(CodeSection* dest);
1235 void unpack_data();
1236
1237 void fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest);
1238 address target(); // if _target==NULL, fetch addr from code stream
1239 address value() { return target(); }
1240 };
1241
1242 class internal_word_Relocation : public DataRelocation {
1243 relocInfo::relocType type() { return relocInfo::internal_word_type; }
1244
1245 public:
1246 static RelocationHolder spec(address target) {
1247 assert(target != NULL, "must not be null");
1248 RelocationHolder rh = newHolder();
1249 new(rh) internal_word_Relocation(target);
1250 return rh;
1251 }
1252
1253 // use this one where all the bits of the target can fit in the code stream:
1254 static RelocationHolder spec_for_immediate() {
1255 RelocationHolder rh = newHolder();
1256 new(rh) internal_word_Relocation(NULL);
1257 return rh;
1258 }
1259
1260 internal_word_Relocation(address target) {
1261 _target = target;
1262 _section = -1; // self-relative
1263 }
1264
1265 protected:
1266 address _target; // address in CodeBlob
1267 int _section; // section providing base address, if any
1268
1269 friend class RelocIterator;
1270 internal_word_Relocation() { }
1271
1272 // bit-width of LSB field in packed offset, if section >= 0
1273 enum { section_width = 2 }; // must equal CodeBuffer::sect_bits
1274
1275 public:
1276 // data is packed as a scaled offset in "1_int" format: [o] or [Oo]
1277 // If the "o" value is 0 (i.e., _target is NULL), the offset is stored
1278 // in the code stream. See internal_word_Relocation::target().
1279 // If _section is not -1, it is appended to the low bits of the offset.
1280 void pack_data_to(CodeSection* dest);
1281 void unpack_data();
1282
1283 void fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest);
1284 address target(); // if _target==NULL, fetch addr from code stream
1285 int section() { return _section; }
1286 address value() { return target(); }
1287 };
1288
1289 class section_word_Relocation : public internal_word_Relocation {
1290 relocInfo::relocType type() { return relocInfo::section_word_type; }
1291
1292 public:
1293 static RelocationHolder spec(address target, int section) {
1294 RelocationHolder rh = newHolder();
1295 new(rh) section_word_Relocation(target, section);
1296 return rh;
1297 }
1298
1299 section_word_Relocation(address target, int section) {
1300 assert(target != NULL, "must not be null");
1301 assert(section >= 0, "must be a valid section");
1302 _target = target;
1303 _section = section;
1304 }
1305
1306 //void pack_data_to -- inherited
1307 void unpack_data();
1308
1309 private:
1310 friend class RelocIterator;
1311 section_word_Relocation() { }
1312 };
1313
1314
1315 class poll_Relocation : public Relocation {
1316 bool is_data() { return true; }
1317 relocInfo::relocType type() { return relocInfo::poll_type; }
1318 void fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest);
1319 };
1320
1321 class poll_return_Relocation : public Relocation {
1322 bool is_data() { return true; }
1323 relocInfo::relocType type() { return relocInfo::poll_return_type; }
1324 void fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest);
1325 };
1326
1327 // We know all the xxx_Relocation classes, so now we can define these:
1328 #define EACH_CASE(name) \
1329 inline name##_Relocation* RelocIterator::name##_reloc() { \
1330 assert(type() == relocInfo::name##_type, "type must agree"); \
1331 /* The purpose of the placed "new" is to re-use the same */ \
1332 /* stack storage for each new iteration. */ \
1333 name##_Relocation* r = new(_rh) name##_Relocation(); \
1334 r->set_binding(this); \
1335 r->name##_Relocation::unpack_data(); \
1336 return r; \
1337 }
1338 APPLY_TO_RELOCATIONS(EACH_CASE);
1339 #undef EACH_CASE
1340
1341 inline RelocIterator::RelocIterator(nmethod* nm, address begin, address limit) {
1342 initialize(nm, begin, limit);
1343 }
1344
1345 #endif // SHARE_VM_CODE_RELOCINFO_HPP