1 /*
2 * Copyright (c) 1997, 2025, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "code/codeCache.hpp"
26 #include "code/compiledIC.hpp"
27 #include "code/nmethod.hpp"
28 #include "code/relocInfo.hpp"
29 #include "memory/resourceArea.hpp"
30 #include "memory/universe.hpp"
31 #include "oops/compressedOops.inline.hpp"
32 #include "oops/oop.inline.hpp"
33 #include "runtime/flags/flagSetting.hpp"
34 #include "runtime/stubCodeGenerator.hpp"
35 #include "utilities/align.hpp"
36 #include "utilities/checkedCast.hpp"
37 #include "utilities/copy.hpp"
38
39 #include <new>
40 #include <type_traits>
41
42 const RelocationHolder RelocationHolder::none; // its type is relocInfo::none
43
44
45 // Implementation of relocInfo
46
47 #ifdef ASSERT
48 relocInfo::relocType relocInfo::check_relocType(relocType type) {
49 assert(type != data_prefix_tag, "cannot build a prefix this way");
50 assert((type & type_mask) == type, "wrong type");
51 return type;
52 }
53
54 void relocInfo::check_offset_and_format(int offset, int format) {
55 assert(offset >= 0 && offset < offset_limit(), "offset out off bounds");
56 assert(is_aligned(offset, offset_unit), "misaligned offset");
57 assert((format & format_mask) == format, "wrong format");
58 }
59 #endif // ASSERT
60
61 void relocInfo::initialize(CodeSection* dest, Relocation* reloc) {
62 relocInfo* data = this+1; // here's where the data might go
63 dest->set_locs_end(data); // sync end: the next call may read dest.locs_end
64 reloc->pack_data_to(dest); // maybe write data into locs, advancing locs_end
65 relocInfo* data_limit = dest->locs_end();
66 if (data_limit > data) {
67 relocInfo suffix = (*this);
68 data_limit = this->finish_prefix((short*) data_limit);
69 // Finish up with the suffix. (Hack note: pack_data_to might edit this.)
70 *data_limit = suffix;
71 dest->set_locs_end(data_limit+1);
72 }
73 }
74
75 relocInfo* relocInfo::finish_prefix(short* prefix_limit) {
76 assert(sizeof(relocInfo) == sizeof(short), "change this code");
77 short* p = (short*)(this+1);
78 assert(prefix_limit >= p, "must be a valid span of data");
79 int plen = checked_cast<int>(prefix_limit - p);
80 if (plen == 0) {
81 debug_only(_value = 0xFFFF);
82 return this; // no data: remove self completely
83 }
84 if (plen == 1 && fits_into_immediate(p[0])) {
85 (*this) = immediate_relocInfo(p[0]); // move data inside self
86 return this+1;
87 }
88 // cannot compact, so just update the count and return the limit pointer
89 (*this) = prefix_info(plen); // write new datalen
90 assert(data() + datalen() == prefix_limit, "pointers must line up");
91 return (relocInfo*)prefix_limit;
92 }
93
94 void relocInfo::set_type(relocType t) {
95 int old_offset = addr_offset();
96 int old_format = format();
97 (*this) = relocInfo(t, old_offset, old_format);
98 assert(type()==(int)t, "sanity check");
99 assert(addr_offset()==old_offset, "sanity check");
100 assert(format()==old_format, "sanity check");
101 }
102
103 void relocInfo::change_reloc_info_for_address(RelocIterator *itr, address pc, relocType old_type, relocType new_type) {
104 bool found = false;
105 while (itr->next() && !found) {
106 if (itr->addr() == pc) {
107 assert(itr->type()==old_type, "wrong relocInfo type found");
108 itr->current()->set_type(new_type);
109 found=true;
110 }
111 }
112 assert(found, "no relocInfo found for pc");
113 }
114
115
116 // ----------------------------------------------------------------------------------------------------
117 // Implementation of RelocIterator
118
119 void RelocIterator::initialize(nmethod* nm, address begin, address limit) {
120 initialize_misc();
121
122 if (nm == nullptr && begin != nullptr) {
123 // allow nmethod to be deduced from beginning address
124 CodeBlob* cb = CodeCache::find_blob(begin);
125 nm = (cb != nullptr) ? cb->as_nmethod_or_null() : nullptr;
126 }
127 guarantee(nm != nullptr, "must be able to deduce nmethod from other arguments");
128
129 _code = nm;
130 _current = nm->relocation_begin() - 1;
131 _end = nm->relocation_end();
132 _addr = nm->content_begin();
133
134 // Initialize code sections.
135 _section_start[CodeBuffer::SECT_CONSTS] = nm->consts_begin();
136 _section_start[CodeBuffer::SECT_INSTS ] = nm->insts_begin() ;
137 _section_start[CodeBuffer::SECT_STUBS ] = nm->stub_begin() ;
138
139 _section_end [CodeBuffer::SECT_CONSTS] = nm->consts_end() ;
140 _section_end [CodeBuffer::SECT_INSTS ] = nm->insts_end() ;
141 _section_end [CodeBuffer::SECT_STUBS ] = nm->stub_end() ;
142
143 assert(!has_current(), "just checking");
144 assert(begin == nullptr || begin >= nm->code_begin(), "in bounds");
145 assert(limit == nullptr || limit <= nm->code_end(), "in bounds");
146 set_limits(begin, limit);
147 }
148
149
150 RelocIterator::RelocIterator(CodeSection* cs, address begin, address limit) {
151 initialize_misc();
152 assert(((cs->locs_start() != nullptr) && (cs->locs_end() != nullptr)), "valid start and end pointer");
153 _current = cs->locs_start()-1;
154 _end = cs->locs_end();
155 _addr = cs->start();
156 _code = nullptr; // Not cb->blob();
157
158 CodeBuffer* cb = cs->outer();
159 assert((int) SECT_LIMIT == CodeBuffer::SECT_LIMIT, "my copy must be equal");
160 for (int n = (int) CodeBuffer::SECT_FIRST; n < (int) CodeBuffer::SECT_LIMIT; n++) {
161 CodeSection* cs = cb->code_section(n);
162 _section_start[n] = cs->start();
163 _section_end [n] = cs->end();
164 }
165
166 assert(!has_current(), "just checking");
167
168 assert(begin == nullptr || begin >= cs->start(), "in bounds");
169 assert(limit == nullptr || limit <= cs->end(), "in bounds");
170 set_limits(begin, limit);
171 }
172
173 bool RelocIterator::addr_in_const() const {
174 const int n = CodeBuffer::SECT_CONSTS;
175 return section_start(n) <= addr() && addr() < section_end(n);
176 }
177
178
179 void RelocIterator::set_limits(address begin, address limit) {
180 _limit = limit;
181
182 // the limit affects this next stuff:
183 if (begin != nullptr) {
184 relocInfo* backup;
185 address backup_addr;
186 while (true) {
187 backup = _current;
188 backup_addr = _addr;
189 if (!next() || addr() >= begin) break;
190 }
191 // At this point, either we are at the first matching record,
192 // or else there is no such record, and !has_current().
193 // In either case, revert to the immediately preceding state.
194 _current = backup;
195 _addr = backup_addr;
196 set_has_current(false);
197 }
198 }
199
200
201 // All the strange bit-encodings are in here.
202 // The idea is to encode relocation data which are small integers
203 // very efficiently (a single extra halfword). Larger chunks of
204 // relocation data need a halfword header to hold their size.
205 void RelocIterator::advance_over_prefix() {
206 if (_current->is_datalen()) {
207 _data = (short*) _current->data();
208 _datalen = _current->datalen();
209 _current += _datalen + 1; // skip the embedded data & header
210 } else {
211 _databuf = _current->immediate();
212 _data = &_databuf;
213 _datalen = 1;
214 _current++; // skip the header
215 }
216 // The client will see the following relocInfo, whatever that is.
217 // It is the reloc to which the preceding data applies.
218 }
219
220
221 void RelocIterator::initialize_misc() {
222 set_has_current(false);
223 for (int i = (int) CodeBuffer::SECT_FIRST; i < (int) CodeBuffer::SECT_LIMIT; i++) {
224 _section_start[i] = nullptr; // these will be lazily computed, if needed
225 _section_end [i] = nullptr;
226 }
227 }
228
229
230 Relocation* RelocIterator::reloc() {
231 // (take the "switch" out-of-line)
232 relocInfo::relocType t = type();
233 if (false) {}
234 #define EACH_TYPE(name) \
235 else if (t == relocInfo::name##_type) { \
236 return name##_reloc(); \
237 }
238 APPLY_TO_RELOCATIONS(EACH_TYPE);
239 #undef EACH_TYPE
240 assert(t == relocInfo::none, "must be padding");
241 _rh = RelocationHolder::none;
242 return _rh.reloc();
243 }
244
245 // Verify all the destructors are trivial, so we don't need to worry about
246 // destroying old contents of a RelocationHolder being assigned or destroyed.
247 #define VERIFY_TRIVIALLY_DESTRUCTIBLE_AUX(Reloc) \
248 static_assert(std::is_trivially_destructible<Reloc>::value, "must be");
249
250 #define VERIFY_TRIVIALLY_DESTRUCTIBLE(name) \
251 VERIFY_TRIVIALLY_DESTRUCTIBLE_AUX(PASTE_TOKENS(name, _Relocation));
252
253 APPLY_TO_RELOCATIONS(VERIFY_TRIVIALLY_DESTRUCTIBLE)
254 VERIFY_TRIVIALLY_DESTRUCTIBLE_AUX(Relocation)
255
256 #undef VERIFY_TRIVIALLY_DESTRUCTIBLE_AUX
257 #undef VERIFY_TRIVIALLY_DESTRUCTIBLE
258
259 // Define all the copy_into functions. These rely on all Relocation types
260 // being trivially destructible (verified above). So it doesn't matter
261 // whether the target holder has been previously initialized or not. There's
262 // no need to consider that distinction and destruct the relocation in an
263 // already initialized holder.
264 #define DEFINE_COPY_INTO_AUX(Reloc) \
265 void Reloc::copy_into(RelocationHolder& holder) const { \
266 copy_into_helper(*this, holder); \
267 }
268
269 #define DEFINE_COPY_INTO(name) \
270 DEFINE_COPY_INTO_AUX(PASTE_TOKENS(name, _Relocation))
271
272 APPLY_TO_RELOCATIONS(DEFINE_COPY_INTO)
273 DEFINE_COPY_INTO_AUX(Relocation)
274
275 #undef DEFINE_COPY_INTO_AUX
276 #undef DEFINE_COPY_INTO
277
278 //////// Methods for flyweight Relocation types
279
280 // some relocations can compute their own values
281 address Relocation::value() {
282 ShouldNotReachHere();
283 return nullptr;
284 }
285
286
287 void Relocation::set_value(address x) {
288 ShouldNotReachHere();
289 }
290
291 void Relocation::const_set_data_value(address x) {
292 #ifdef _LP64
293 if (format() == relocInfo::narrow_oop_in_const) {
294 *(narrowOop*)addr() = CompressedOops::encode(cast_to_oop(x));
295 } else {
296 #endif
297 *(address*)addr() = x;
298 #ifdef _LP64
299 }
300 #endif
301 }
302
303 void Relocation::const_verify_data_value(address x) {
304 #ifdef _LP64
305 if (format() == relocInfo::narrow_oop_in_const) {
306 guarantee(*(narrowOop*)addr() == CompressedOops::encode(cast_to_oop(x)), "must agree");
307 } else {
308 #endif
309 guarantee(*(address*)addr() == x, "must agree");
310 #ifdef _LP64
311 }
312 #endif
313 }
314
315
316 RelocationHolder Relocation::spec_simple(relocInfo::relocType rtype) {
317 if (rtype == relocInfo::none) return RelocationHolder::none;
318 relocInfo ri = relocInfo(rtype, 0);
319 RelocIterator itr;
320 itr.set_current(ri);
321 itr.reloc();
322 return itr._rh;
323 }
324
325 address Relocation::old_addr_for(address newa,
326 const CodeBuffer* src, CodeBuffer* dest) {
327 int sect = dest->section_index_of(newa);
328 guarantee(sect != CodeBuffer::SECT_NONE, "lost track of this address");
329 address ostart = src->code_section(sect)->start();
330 address nstart = dest->code_section(sect)->start();
331 return ostart + (newa - nstart);
332 }
333
334 address Relocation::new_addr_for(address olda,
335 const CodeBuffer* src, CodeBuffer* dest) {
336 debug_only(const CodeBuffer* src0 = src);
337 int sect = CodeBuffer::SECT_NONE;
338 // Look for olda in the source buffer, and all previous incarnations
339 // if the source buffer has been expanded.
340 for (; src != nullptr; src = src->before_expand()) {
341 sect = src->section_index_of(olda);
342 if (sect != CodeBuffer::SECT_NONE) break;
343 }
344 guarantee(sect != CodeBuffer::SECT_NONE, "lost track of this address");
345 address ostart = src->code_section(sect)->start();
346 address nstart = dest->code_section(sect)->start();
347 return nstart + (olda - ostart);
348 }
349
350 void Relocation::normalize_address(address& addr, const CodeSection* dest, bool allow_other_sections) {
351 address addr0 = addr;
352 if (addr0 == nullptr || dest->allocates2(addr0)) return;
353 CodeBuffer* cb = dest->outer();
354 addr = new_addr_for(addr0, cb, cb);
355 assert(allow_other_sections || dest->contains2(addr),
356 "addr must be in required section");
357 }
358
359
360 void CallRelocation::set_destination(address x) {
361 pd_set_call_destination(x);
362 }
363
364 void CallRelocation::fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest) {
365 // Usually a self-relative reference to an external routine.
366 // On some platforms, the reference is absolute (not self-relative).
367 // The enhanced use of pd_call_destination sorts this all out.
368 address orig_addr = old_addr_for(addr(), src, dest);
369 address callee = pd_call_destination(orig_addr);
370 // Reassert the callee address, this time in the new copy of the code.
371 pd_set_call_destination(callee);
372 }
373
374
375 #ifdef USE_TRAMPOLINE_STUB_FIX_OWNER
376 void trampoline_stub_Relocation::fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest) {
377 // Finalize owner destination only for nmethods
378 if (dest->blob() != nullptr) return;
379 pd_fix_owner_after_move();
380 }
381 #endif
382
383 //// pack/unpack methods
384
385 void oop_Relocation::pack_data_to(CodeSection* dest) {
386 short* p = (short*) dest->locs_end();
387 p = pack_1_int_to(p, _oop_index);
388 dest->set_locs_end((relocInfo*) p);
389 }
390
391
392 void oop_Relocation::unpack_data() {
393 _oop_index = unpack_1_int();
394 }
395
396 void metadata_Relocation::pack_data_to(CodeSection* dest) {
397 short* p = (short*) dest->locs_end();
398 p = pack_1_int_to(p, _metadata_index);
399 dest->set_locs_end((relocInfo*) p);
400 }
401
402
403 void metadata_Relocation::unpack_data() {
404 _metadata_index = unpack_1_int();
405 }
406
407
408 void virtual_call_Relocation::pack_data_to(CodeSection* dest) {
409 short* p = (short*) dest->locs_end();
410 address point = dest->locs_point();
411
412 normalize_address(_cached_value, dest);
413 jint x0 = scaled_offset_null_special(_cached_value, point);
414 p = pack_2_ints_to(p, x0, _method_index);
415 dest->set_locs_end((relocInfo*) p);
416 }
417
418
419 void virtual_call_Relocation::unpack_data() {
420 jint x0 = 0;
421 unpack_2_ints(x0, _method_index);
422 address point = addr();
423 _cached_value = x0==0? nullptr: address_from_scaled_offset(x0, point);
424 }
425
426 void runtime_call_w_cp_Relocation::pack_data_to(CodeSection * dest) {
427 short* p = pack_1_int_to((short *)dest->locs_end(), (jint)(_offset >> 2));
428 dest->set_locs_end((relocInfo*) p);
429 }
430
431 void runtime_call_w_cp_Relocation::unpack_data() {
432 _offset = unpack_1_int() << 2;
433 }
434
435 void static_stub_Relocation::pack_data_to(CodeSection* dest) {
436 short* p = (short*) dest->locs_end();
437 CodeSection* insts = dest->outer()->insts();
438 normalize_address(_static_call, insts);
439 p = pack_1_int_to(p, scaled_offset(_static_call, insts->start()));
440 dest->set_locs_end((relocInfo*) p);
441 }
442
443 void static_stub_Relocation::unpack_data() {
444 address base = binding()->section_start(CodeBuffer::SECT_INSTS);
445 jint offset = unpack_1_int();
446 _static_call = address_from_scaled_offset(offset, base);
447 }
448
449 void trampoline_stub_Relocation::pack_data_to(CodeSection* dest ) {
450 short* p = (short*) dest->locs_end();
451 CodeSection* insts = dest->outer()->insts();
452 normalize_address(_owner, insts);
453 p = pack_1_int_to(p, scaled_offset(_owner, insts->start()));
454 dest->set_locs_end((relocInfo*) p);
455 }
456
457 void trampoline_stub_Relocation::unpack_data() {
458 address base = binding()->section_start(CodeBuffer::SECT_INSTS);
459 _owner = address_from_scaled_offset(unpack_1_int(), base);
460 }
461
462 void external_word_Relocation::pack_data_to(CodeSection* dest) {
463 short* p = (short*) dest->locs_end();
464 int index = ExternalsRecorder::find_index(_target);
465 p = pack_1_int_to(p, index);
466 dest->set_locs_end((relocInfo*) p);
467 }
468
469
470 void external_word_Relocation::unpack_data() {
471 int index = unpack_1_int();
472 _target = ExternalsRecorder::at(index);
473 }
474
475
476 void internal_word_Relocation::pack_data_to(CodeSection* dest) {
477 short* p = (short*) dest->locs_end();
478 normalize_address(_target, dest, true);
479
480 // Check whether my target address is valid within this section.
481 // If not, strengthen the relocation type to point to another section.
482 int sindex = _section;
483 if (sindex == CodeBuffer::SECT_NONE && _target != nullptr
484 && (!dest->allocates(_target) || _target == dest->locs_point())) {
485 sindex = dest->outer()->section_index_of(_target);
486 guarantee(sindex != CodeBuffer::SECT_NONE, "must belong somewhere");
487 relocInfo* base = dest->locs_end() - 1;
488 assert(base->type() == this->type(), "sanity");
489 // Change the written type, to be section_word_type instead.
490 base->set_type(relocInfo::section_word_type);
491 }
492
493 // Note: An internal_word relocation cannot refer to its own instruction,
494 // because we reserve "0" to mean that the pointer itself is embedded
495 // in the code stream. We use a section_word relocation for such cases.
496
497 if (sindex == CodeBuffer::SECT_NONE) {
498 assert(type() == relocInfo::internal_word_type, "must be base class");
499 guarantee(_target == nullptr || dest->allocates2(_target), "must be within the given code section");
500 jint x0 = scaled_offset_null_special(_target, dest->locs_point());
501 assert(!(x0 == 0 && _target != nullptr), "correct encoding of null target");
502 p = pack_1_int_to(p, x0);
503 } else {
504 assert(_target != nullptr, "sanity");
505 CodeSection* sect = dest->outer()->code_section(sindex);
506 guarantee(sect->allocates2(_target), "must be in correct section");
507 address base = sect->start();
508 jint offset = scaled_offset(_target, base);
509 assert((uint)sindex < (uint)CodeBuffer::SECT_LIMIT, "sanity");
510 assert(CodeBuffer::SECT_LIMIT <= (1 << section_width), "section_width++");
511 p = pack_1_int_to(p, (offset << section_width) | sindex);
512 }
513
514 dest->set_locs_end((relocInfo*) p);
515 }
516
517
518 void internal_word_Relocation::unpack_data() {
519 jint x0 = unpack_1_int();
520 _target = x0==0? nullptr: address_from_scaled_offset(x0, addr());
521 _section = CodeBuffer::SECT_NONE;
522 }
523
524
525 void section_word_Relocation::unpack_data() {
526 jint x = unpack_1_int();
527 jint offset = (x >> section_width);
528 int sindex = (x & ((1<<section_width)-1));
529 address base = binding()->section_start(sindex);
530
531 _section = sindex;
532 _target = address_from_scaled_offset(offset, base);
533 }
534
535 //// miscellaneous methods
536 oop* oop_Relocation::oop_addr() {
537 int n = _oop_index;
538 if (n == 0) {
539 // oop is stored in the code stream
540 return (oop*) pd_address_in_code();
541 } else {
542 // oop is stored in table at nmethod::oops_begin
543 return code()->oop_addr_at(n);
544 }
545 }
546
547
548 oop oop_Relocation::oop_value() {
549 // clean inline caches store a special pseudo-null
550 if (Universe::contains_non_oop_word(oop_addr())) {
551 return nullptr;
552 }
553 return *oop_addr();
554 }
555
556
557 void oop_Relocation::fix_oop_relocation() {
558 if (!oop_is_immediate()) {
559 // get the oop from the pool, and re-insert it into the instruction:
560 set_value(value());
561 }
562 }
563
564
565 void oop_Relocation::verify_oop_relocation() {
566 if (!oop_is_immediate()) {
567 // get the oop from the pool, and re-insert it into the instruction:
568 verify_value(value());
569 }
570 }
571
572 // meta data versions
573 Metadata** metadata_Relocation::metadata_addr() {
574 int n = _metadata_index;
575 if (n == 0) {
576 // metadata is stored in the code stream
577 return (Metadata**) pd_address_in_code();
578 } else {
579 // metadata is stored in table at nmethod::metadatas_begin
580 return code()->metadata_addr_at(n);
581 }
582 }
583
584
585 Metadata* metadata_Relocation::metadata_value() {
586 Metadata* v = *metadata_addr();
587 // clean inline caches store a special pseudo-null
588 if (v == (Metadata*)Universe::non_oop_word()) v = nullptr;
589 return v;
590 }
591
592
593 void metadata_Relocation::fix_metadata_relocation() {
594 if (!metadata_is_immediate()) {
595 // get the metadata from the pool, and re-insert it into the instruction:
596 pd_fix_value(value());
597 }
598 }
599
600 address virtual_call_Relocation::cached_value() {
601 assert(_cached_value != nullptr && _cached_value < addr(), "must precede ic_call");
602 return _cached_value;
603 }
604
605 Method* virtual_call_Relocation::method_value() {
606 nmethod* nm = code();
607 if (nm == nullptr) return (Method*)nullptr;
608 Metadata* m = nm->metadata_at(_method_index);
609 assert(m != nullptr || _method_index == 0, "should be non-null for non-zero index");
610 assert(m == nullptr || m->is_method(), "not a method");
611 return (Method*)m;
612 }
613
614 void virtual_call_Relocation::clear_inline_cache() {
615 ResourceMark rm;
616 CompiledIC* icache = CompiledIC_at(this);
617 icache->set_to_clean();
618 }
619
620
621 void opt_virtual_call_Relocation::pack_data_to(CodeSection* dest) {
622 short* p = (short*) dest->locs_end();
623 p = pack_1_int_to(p, _method_index);
624 dest->set_locs_end((relocInfo*) p);
625 }
626
627 void opt_virtual_call_Relocation::unpack_data() {
628 _method_index = unpack_1_int();
629 }
630
631 Method* opt_virtual_call_Relocation::method_value() {
632 nmethod* nm = code();
633 if (nm == nullptr) return (Method*)nullptr;
634 Metadata* m = nm->metadata_at(_method_index);
635 assert(m != nullptr || _method_index == 0, "should be non-null for non-zero index");
636 assert(m == nullptr || m->is_method(), "not a method");
637 return (Method*)m;
638 }
639
640 void opt_virtual_call_Relocation::clear_inline_cache() {
641 ResourceMark rm;
642 CompiledDirectCall* callsite = CompiledDirectCall::at(this);
643 callsite->set_to_clean();
644 }
645
646 address opt_virtual_call_Relocation::static_stub() {
647 // search for the static stub who points back to this static call
648 address static_call_addr = addr();
649 RelocIterator iter(code());
650 while (iter.next()) {
651 if (iter.type() == relocInfo::static_stub_type) {
652 static_stub_Relocation* stub_reloc = iter.static_stub_reloc();
653 if (stub_reloc->static_call() == static_call_addr) {
654 return iter.addr();
655 }
656 }
657 }
658 return nullptr;
659 }
660
661 Method* static_call_Relocation::method_value() {
662 nmethod* nm = code();
663 if (nm == nullptr) return (Method*)nullptr;
664 Metadata* m = nm->metadata_at(_method_index);
665 assert(m != nullptr || _method_index == 0, "should be non-null for non-zero index");
666 assert(m == nullptr || m->is_method(), "not a method");
667 return (Method*)m;
668 }
669
670 void static_call_Relocation::pack_data_to(CodeSection* dest) {
671 short* p = (short*) dest->locs_end();
672 p = pack_1_int_to(p, _method_index);
673 dest->set_locs_end((relocInfo*) p);
674 }
675
676 void static_call_Relocation::unpack_data() {
677 _method_index = unpack_1_int();
678 }
679
680 void static_call_Relocation::clear_inline_cache() {
681 ResourceMark rm;
682 CompiledDirectCall* callsite = CompiledDirectCall::at(this);
683 callsite->set_to_clean();
684 }
685
686
687 address static_call_Relocation::static_stub() {
688 // search for the static stub who points back to this static call
689 address static_call_addr = addr();
690 RelocIterator iter(code());
691 while (iter.next()) {
692 if (iter.type() == relocInfo::static_stub_type) {
693 static_stub_Relocation* stub_reloc = iter.static_stub_reloc();
694 if (stub_reloc->static_call() == static_call_addr) {
695 return iter.addr();
696 }
697 }
698 }
699 return nullptr;
700 }
701
702 // Finds the trampoline address for a call. If no trampoline stub is
703 // found nullptr is returned which can be handled by the caller.
704 address trampoline_stub_Relocation::get_trampoline_for(address call, nmethod* code) {
705 // There are no relocations available when the code gets relocated
706 // because of CodeBuffer expansion.
707 if (code->relocation_size() == 0)
708 return nullptr;
709
710 RelocIterator iter(code, call);
711 while (iter.next()) {
712 if (iter.type() == relocInfo::trampoline_stub_type) {
713 if (iter.trampoline_stub_reloc()->owner() == call) {
714 return iter.addr();
715 }
716 }
717 }
718
719 return nullptr;
720 }
721
722 void static_stub_Relocation::clear_inline_cache() {
723 // Call stub is only used when calling the interpreted code.
724 // It does not really need to be cleared, except that we want to clean out the methodoop.
725 CompiledDirectCall::set_stub_to_clean(this);
726 }
727
728
729 void external_word_Relocation::fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest) {
730 if (_target != nullptr) {
731 // Probably this reference is absolute, not relative, so the following is
732 // probably a no-op.
733 set_value(_target);
734 }
735 // If target is nullptr, this is an absolute embedded reference to an external
736 // location, which means there is nothing to fix here. In either case, the
737 // resulting target should be an "external" address.
738 postcond(src->section_index_of(target()) == CodeBuffer::SECT_NONE);
739 postcond(dest->section_index_of(target()) == CodeBuffer::SECT_NONE);
740 }
741
742
743 address external_word_Relocation::target() {
744 address target = _target;
745 if (target == nullptr) {
746 target = pd_get_address_from_code();
747 }
748 return target;
749 }
750
751
752 void internal_word_Relocation::fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest) {
753 address target = _target;
754 if (target == nullptr) {
755 target = new_addr_for(this->target(), src, dest);
756 }
757 set_value(target);
758 }
759
760
761 address internal_word_Relocation::target() {
762 address target = _target;
763 if (target == nullptr) {
764 if (addr_in_const()) {
765 target = *(address*)addr();
766 } else {
767 target = pd_get_address_from_code();
768 }
769 }
770 return target;
771 }
772
773 //---------------------------------------------------------------------------------
774 // Non-product code
775
776 #ifndef PRODUCT
777
778 static const char* reloc_type_string(relocInfo::relocType t) {
779 switch (t) {
780 #define EACH_CASE(name) \
781 case relocInfo::name##_type: \
782 return #name;
783
784 APPLY_TO_RELOCATIONS(EACH_CASE);
785 #undef EACH_CASE
786
787 case relocInfo::none:
788 return "none";
789 case relocInfo::data_prefix_tag:
790 return "prefix";
791 default:
792 return "UNKNOWN RELOC TYPE";
793 }
794 }
795
796
797 void RelocIterator::print_current() {
798 if (!has_current()) {
799 tty->print_cr("(no relocs)");
800 return;
801 }
802 tty->print("relocInfo@" INTPTR_FORMAT " [type=%d(%s) addr=" INTPTR_FORMAT " offset=%d",
803 p2i(_current), type(), reloc_type_string((relocInfo::relocType) type()), p2i(_addr), _current->addr_offset());
804 if (current()->format() != 0)
805 tty->print(" format=%d", current()->format());
806 if (datalen() == 1) {
807 tty->print(" data=%d", data()[0]);
808 } else if (datalen() > 0) {
809 tty->print(" data={");
810 for (int i = 0; i < datalen(); i++) {
811 tty->print("%04x", data()[i] & 0xFFFF);
812 }
813 tty->print("}");
814 }
815 tty->print("]");
816 switch (type()) {
817 case relocInfo::oop_type:
818 {
819 oop_Relocation* r = oop_reloc();
820 oop* oop_addr = nullptr;
821 oop raw_oop = nullptr;
822 oop oop_value = nullptr;
823 if (code() != nullptr || r->oop_is_immediate()) {
824 oop_addr = r->oop_addr();
825 raw_oop = *oop_addr;
826 oop_value = r->oop_value();
827 }
828 tty->print(" | [oop_addr=" INTPTR_FORMAT " *=" INTPTR_FORMAT "]",
829 p2i(oop_addr), p2i(raw_oop));
830 // Do not print the oop by default--we want this routine to
831 // work even during GC or other inconvenient times.
832 if (WizardMode && oop_value != nullptr) {
833 tty->print("oop_value=" INTPTR_FORMAT ": ", p2i(oop_value));
834 if (oopDesc::is_oop(oop_value)) {
835 oop_value->print_value_on(tty);
836 }
837 }
838 break;
839 }
840 case relocInfo::metadata_type:
841 {
842 metadata_Relocation* r = metadata_reloc();
843 Metadata** metadata_addr = nullptr;
844 Metadata* raw_metadata = nullptr;
845 Metadata* metadata_value = nullptr;
846 if (code() != nullptr || r->metadata_is_immediate()) {
847 metadata_addr = r->metadata_addr();
848 raw_metadata = *metadata_addr;
849 metadata_value = r->metadata_value();
850 }
851 tty->print(" | [metadata_addr=" INTPTR_FORMAT " *=" INTPTR_FORMAT "]",
852 p2i(metadata_addr), p2i(raw_metadata));
853 if (metadata_value != nullptr) {
854 tty->print("metadata_value=" INTPTR_FORMAT ": ", p2i(metadata_value));
855 metadata_value->print_value_on(tty);
856 }
857 break;
858 }
859 case relocInfo::external_word_type:
860 case relocInfo::internal_word_type:
861 case relocInfo::section_word_type:
862 {
863 DataRelocation* r = (DataRelocation*) reloc();
864 tty->print(" | [target=" INTPTR_FORMAT "]", p2i(r->value())); //value==target
865 break;
866 }
867 case relocInfo::static_call_type:
868 {
869 static_call_Relocation* r = (static_call_Relocation*) reloc();
870 tty->print(" | [destination=" INTPTR_FORMAT " metadata=" INTPTR_FORMAT "]",
871 p2i(r->destination()), p2i(r->method_value()));
872 break;
873 }
874 case relocInfo::runtime_call_type:
875 case relocInfo::runtime_call_w_cp_type:
876 {
877 CallRelocation* r = (CallRelocation*) reloc();
878 tty->print(" | [destination=" INTPTR_FORMAT "]", p2i(r->destination()));
879 break;
880 }
881 case relocInfo::virtual_call_type:
882 {
883 virtual_call_Relocation* r = (virtual_call_Relocation*) reloc();
884 tty->print(" | [destination=" INTPTR_FORMAT " cached_value=" INTPTR_FORMAT " metadata=" INTPTR_FORMAT "]",
885 p2i(r->destination()), p2i(r->cached_value()), p2i(r->method_value()));
886 break;
887 }
888 case relocInfo::static_stub_type:
889 {
890 static_stub_Relocation* r = (static_stub_Relocation*) reloc();
891 tty->print(" | [static_call=" INTPTR_FORMAT "]", p2i(r->static_call()));
892 break;
893 }
894 case relocInfo::trampoline_stub_type:
895 {
896 trampoline_stub_Relocation* r = (trampoline_stub_Relocation*) reloc();
897 tty->print(" | [trampoline owner=" INTPTR_FORMAT "]", p2i(r->owner()));
898 break;
899 }
900 case relocInfo::opt_virtual_call_type:
901 {
902 opt_virtual_call_Relocation* r = (opt_virtual_call_Relocation*) reloc();
903 tty->print(" | [destination=" INTPTR_FORMAT " metadata=" INTPTR_FORMAT "]",
904 p2i(r->destination()), p2i(r->method_value()));
905 break;
906 }
907 default:
908 break;
909 }
910 tty->cr();
911 }
912
913
914 void RelocIterator::print() {
915 RelocIterator save_this = (*this);
916 relocInfo* scan = _current;
917 if (!has_current()) scan += 1; // nothing to scan here!
918
919 bool skip_next = has_current();
920 bool got_next;
921 while (true) {
922 got_next = (skip_next || next());
923 skip_next = false;
924
925 tty->print(" @" INTPTR_FORMAT ": ", p2i(scan));
926 relocInfo* newscan = _current+1;
927 if (!has_current()) newscan -= 1; // nothing to scan here!
928 while (scan < newscan) {
929 tty->print("%04x", *(short*)scan & 0xFFFF);
930 scan++;
931 }
932 tty->cr();
933
934 if (!got_next) break;
935 print_current();
936 }
937
938 (*this) = save_this;
939 }
940
941 // For the debugger:
942 extern "C"
943 void print_blob_locs(nmethod* nm) {
944 nm->print();
945 RelocIterator iter(nm);
946 iter.print();
947 }
948 extern "C"
949 void print_buf_locs(CodeBuffer* cb) {
950 FlagSetting fs(PrintRelocations, true);
951 cb->print();
952 }
953 #endif // !PRODUCT