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 "ci/ciUtilities.hpp"
26 #include "code/codeCache.hpp"
27 #include "code/compiledIC.hpp"
28 #include "code/nmethod.hpp"
29 #include "code/relocInfo.hpp"
30 #include "code/SCCache.hpp"
31 #include "memory/resourceArea.hpp"
32 #include "memory/universe.hpp"
33 #include "oops/compressedOops.inline.hpp"
34 #include "oops/oop.inline.hpp"
35 #include "runtime/flags/flagSetting.hpp"
36 #include "runtime/stubCodeGenerator.hpp"
37 #include "utilities/align.hpp"
38 #include "utilities/checkedCast.hpp"
39 #include "utilities/copy.hpp"
40
41 #include <new>
42 #include <type_traits>
43
44 const RelocationHolder RelocationHolder::none; // its type is relocInfo::none
45
46
47 // Implementation of relocInfo
48
49 #ifdef ASSERT
50 relocInfo::relocType relocInfo::check_relocType(relocType type) {
51 assert(type != data_prefix_tag, "cannot build a prefix this way");
52 assert((type & type_mask) == type, "wrong type");
53 return type;
54 }
55
56 void relocInfo::check_offset_and_format(int offset, int format) {
57 assert(offset >= 0 && offset < offset_limit(), "offset out off bounds");
58 assert(is_aligned(offset, offset_unit), "misaligned offset");
59 assert((format & format_mask) == format, "wrong format");
60 }
61 #endif // ASSERT
62
63 void relocInfo::initialize(CodeSection* dest, Relocation* reloc) {
64 relocInfo* data = this+1; // here's where the data might go
65 dest->set_locs_end(data); // sync end: the next call may read dest.locs_end
66 reloc->pack_data_to(dest); // maybe write data into locs, advancing locs_end
67 relocInfo* data_limit = dest->locs_end();
68 if (data_limit > data) {
69 relocInfo suffix = (*this);
70 data_limit = this->finish_prefix((short*) data_limit);
71 // Finish up with the suffix. (Hack note: pack_data_to might edit this.)
72 *data_limit = suffix;
73 dest->set_locs_end(data_limit+1);
74 }
75 }
76
77 relocInfo* relocInfo::finish_prefix(short* prefix_limit) {
78 assert(sizeof(relocInfo) == sizeof(short), "change this code");
79 short* p = (short*)(this+1);
80 assert(prefix_limit >= p, "must be a valid span of data");
81 int plen = checked_cast<int>(prefix_limit - p);
82 if (plen == 0) {
83 debug_only(_value = 0xFFFF);
84 return this; // no data: remove self completely
85 }
86 if (plen == 1 && fits_into_immediate(p[0])) {
87 (*this) = immediate_relocInfo(p[0]); // move data inside self
88 return this+1;
89 }
90 // cannot compact, so just update the count and return the limit pointer
91 (*this) = prefix_info(plen); // write new datalen
92 assert(data() + datalen() == prefix_limit, "pointers must line up");
93 return (relocInfo*)prefix_limit;
94 }
95
96 void relocInfo::set_type(relocType t) {
97 int old_offset = addr_offset();
98 int old_format = format();
99 (*this) = relocInfo(t, old_offset, old_format);
100 assert(type()==(int)t, "sanity check");
101 assert(addr_offset()==old_offset, "sanity check");
102 assert(format()==old_format, "sanity check");
103 }
104
105 void relocInfo::change_reloc_info_for_address(RelocIterator *itr, address pc, relocType old_type, relocType new_type) {
106 bool found = false;
107 while (itr->next() && !found) {
108 if (itr->addr() == pc) {
109 assert(itr->type()==old_type, "wrong relocInfo type found");
110 itr->current()->set_type(new_type);
111 found=true;
112 }
113 }
114 assert(found, "no relocInfo found for pc");
115 }
116
117
118 // ----------------------------------------------------------------------------------------------------
119 // Implementation of RelocIterator
120
121 // A static dummy to serve as a safe pointer when there is no relocation info.
122 static relocInfo dummy_relocInfo = relocInfo(relocInfo::none, 0);
123
124 void RelocIterator::initialize(nmethod* nm, address begin, address limit) {
125 initialize_misc();
126
127 if (nm == nullptr && begin != nullptr) {
128 // allow nmethod to be deduced from beginning address
129 CodeBlob* cb = CodeCache::find_blob(begin);
130 nm = (cb != nullptr) ? cb->as_nmethod_or_null() : nullptr;
131 }
132 guarantee(nm != nullptr, "must be able to deduce nmethod from other arguments");
133
134 _code = nm;
135 if (nm->relocation_size() == 0) {
136 _current = &dummy_relocInfo - 1;
137 _end = &dummy_relocInfo;
138 } else {
139 assert(((nm->relocation_begin() != nullptr) && (nm->relocation_end() != nullptr)), "valid start and end pointer");
140 _current = nm->relocation_begin() - 1;
141 _end = nm->relocation_end();
142 }
143 _addr = nm->content_begin();
144
145 // Initialize code sections.
146 _section_start[CodeBuffer::SECT_CONSTS] = nm->consts_begin();
147 _section_start[CodeBuffer::SECT_INSTS ] = nm->insts_begin() ;
148 _section_start[CodeBuffer::SECT_STUBS ] = nm->stub_begin() ;
149
150 _section_end [CodeBuffer::SECT_CONSTS] = nm->consts_end() ;
151 _section_end [CodeBuffer::SECT_INSTS ] = nm->insts_end() ;
152 _section_end [CodeBuffer::SECT_STUBS ] = nm->stub_end() ;
153
154 assert(!has_current(), "just checking");
155 assert(begin == nullptr || begin >= nm->code_begin(), "in bounds");
156 assert(limit == nullptr || limit <= nm->code_end(), "in bounds");
157 set_limits(begin, limit);
158 }
159
160 RelocIterator::RelocIterator(CodeSection* cs, address begin, address limit) {
161 initialize_misc();
162 assert(((cs->locs_start() != nullptr) && (cs->locs_end() != nullptr)), "valid start and end pointer");
163 _current = cs->locs_start() - 1;
164 _end = cs->locs_end();
165 _addr = cs->start();
166 _code = nullptr; // Not cb->blob();
167
168 CodeBuffer* cb = cs->outer();
169 assert((int) SECT_LIMIT == CodeBuffer::SECT_LIMIT, "my copy must be equal");
170 for (int n = (int) CodeBuffer::SECT_FIRST; n < (int) CodeBuffer::SECT_LIMIT; n++) {
171 CodeSection* cs = cb->code_section(n);
172 _section_start[n] = cs->start();
173 _section_end [n] = cs->end();
174 }
175
176 assert(!has_current(), "just checking");
177
178 assert(begin == nullptr || begin >= cs->start(), "in bounds");
179 assert(limit == nullptr || limit <= cs->end(), "in bounds");
180 set_limits(begin, limit);
181 }
182
183 bool RelocIterator::addr_in_const() const {
184 const int n = CodeBuffer::SECT_CONSTS;
185 if (_section_start[n] == nullptr) {
186 return false;
187 }
188 return section_start(n) <= addr() && addr() < section_end(n);
189 }
190
191
192 void RelocIterator::set_limits(address begin, address limit) {
193 _limit = limit;
194
195 // the limit affects this next stuff:
196 if (begin != nullptr) {
197 relocInfo* backup;
198 address backup_addr;
199 while (true) {
200 backup = _current;
201 backup_addr = _addr;
202 if (!next() || addr() >= begin) break;
203 }
204 // At this point, either we are at the first matching record,
205 // or else there is no such record, and !has_current().
206 // In either case, revert to the immediately preceding state.
207 _current = backup;
208 _addr = backup_addr;
209 set_has_current(false);
210 }
211 }
212
213
214 // All the strange bit-encodings are in here.
215 // The idea is to encode relocation data which are small integers
216 // very efficiently (a single extra halfword). Larger chunks of
217 // relocation data need a halfword header to hold their size.
218 void RelocIterator::advance_over_prefix() {
219 if (_current->is_datalen()) {
220 _data = (short*) _current->data();
221 _datalen = _current->datalen();
222 _current += _datalen + 1; // skip the embedded data & header
223 } else {
224 _databuf = _current->immediate();
225 _data = &_databuf;
226 _datalen = 1;
227 _current++; // skip the header
228 }
229 // The client will see the following relocInfo, whatever that is.
230 // It is the reloc to which the preceding data applies.
231 }
232
233
234 void RelocIterator::initialize_misc() {
235 set_has_current(false);
236 for (int i = (int) CodeBuffer::SECT_FIRST; i < (int) CodeBuffer::SECT_LIMIT; i++) {
237 _section_start[i] = nullptr; // these will be lazily computed, if needed
238 _section_end [i] = nullptr;
239 }
240 }
241
242
243 Relocation* RelocIterator::reloc() {
244 // (take the "switch" out-of-line)
245 relocInfo::relocType t = type();
246 if (false) {}
247 #define EACH_TYPE(name) \
248 else if (t == relocInfo::name##_type) { \
249 return name##_reloc(); \
250 }
251 APPLY_TO_RELOCATIONS(EACH_TYPE);
252 #undef EACH_TYPE
253 assert(t == relocInfo::none, "must be padding");
254 _rh = RelocationHolder::none;
255 return _rh.reloc();
256 }
257
258 // Verify all the destructors are trivial, so we don't need to worry about
259 // destroying old contents of a RelocationHolder being assigned or destroyed.
260 #define VERIFY_TRIVIALLY_DESTRUCTIBLE_AUX(Reloc) \
261 static_assert(std::is_trivially_destructible<Reloc>::value, "must be");
262
263 #define VERIFY_TRIVIALLY_DESTRUCTIBLE(name) \
264 VERIFY_TRIVIALLY_DESTRUCTIBLE_AUX(PASTE_TOKENS(name, _Relocation));
265
266 APPLY_TO_RELOCATIONS(VERIFY_TRIVIALLY_DESTRUCTIBLE)
267 VERIFY_TRIVIALLY_DESTRUCTIBLE_AUX(Relocation)
268
269 #undef VERIFY_TRIVIALLY_DESTRUCTIBLE_AUX
270 #undef VERIFY_TRIVIALLY_DESTRUCTIBLE
271
272 // Define all the copy_into functions. These rely on all Relocation types
273 // being trivially destructible (verified above). So it doesn't matter
274 // whether the target holder has been previously initialized or not. There's
275 // no need to consider that distinction and destruct the relocation in an
276 // already initialized holder.
277 #define DEFINE_COPY_INTO_AUX(Reloc) \
278 void Reloc::copy_into(RelocationHolder& holder) const { \
279 copy_into_helper(*this, holder); \
280 }
281
282 #define DEFINE_COPY_INTO(name) \
283 DEFINE_COPY_INTO_AUX(PASTE_TOKENS(name, _Relocation))
284
285 APPLY_TO_RELOCATIONS(DEFINE_COPY_INTO)
286 DEFINE_COPY_INTO_AUX(Relocation)
287
288 #undef DEFINE_COPY_INTO_AUX
289 #undef DEFINE_COPY_INTO
290
291 //////// Methods for flyweight Relocation types
292
293 // some relocations can compute their own values
294 address Relocation::value() {
295 ShouldNotReachHere();
296 return nullptr;
297 }
298
299
300 void Relocation::set_value(address x) {
301 ShouldNotReachHere();
302 }
303
304 void Relocation::const_set_data_value(address x) {
305 #ifdef _LP64
306 if (format() == relocInfo::narrow_oop_in_const) {
307 *(narrowOop*)addr() = CompressedOops::encode(cast_to_oop(x));
308 } else {
309 #endif
310 *(address*)addr() = x;
311 #ifdef _LP64
312 }
313 #endif
314 }
315
316 void Relocation::const_verify_data_value(address x) {
317 #ifdef _LP64
318 if (format() == relocInfo::narrow_oop_in_const) {
319 guarantee(*(narrowOop*)addr() == CompressedOops::encode(cast_to_oop(x)), "must agree");
320 } else {
321 #endif
322 guarantee(*(address*)addr() == x, "must agree");
323 #ifdef _LP64
324 }
325 #endif
326 }
327
328
329 RelocationHolder Relocation::spec_simple(relocInfo::relocType rtype) {
330 if (rtype == relocInfo::none) return RelocationHolder::none;
331 relocInfo ri = relocInfo(rtype, 0);
332 RelocIterator itr;
333 itr.set_current(ri);
334 itr.reloc();
335 return itr._rh;
336 }
337
338 address Relocation::old_addr_for(address newa,
339 const CodeBuffer* src, CodeBuffer* dest) {
340 int sect = dest->section_index_of(newa);
341 guarantee(sect != CodeBuffer::SECT_NONE, "lost track of this address");
342 address ostart = src->code_section(sect)->start();
343 address nstart = dest->code_section(sect)->start();
344 return ostart + (newa - nstart);
345 }
346
347 address Relocation::new_addr_for(address olda,
348 const CodeBuffer* src, CodeBuffer* dest) {
349 debug_only(const CodeBuffer* src0 = src);
350 int sect = CodeBuffer::SECT_NONE;
351 // Look for olda in the source buffer, and all previous incarnations
352 // if the source buffer has been expanded.
353 for (; src != nullptr; src = src->before_expand()) {
354 sect = src->section_index_of(olda);
355 if (sect != CodeBuffer::SECT_NONE) break;
356 }
357 guarantee(sect != CodeBuffer::SECT_NONE, "lost track of this address");
358 address ostart = src->code_section(sect)->start();
359 address nstart = dest->code_section(sect)->start();
360 return nstart + (olda - ostart);
361 }
362
363 void Relocation::normalize_address(address& addr, const CodeSection* dest, bool allow_other_sections) {
364 address addr0 = addr;
365 if (addr0 == nullptr || dest->allocates2(addr0)) return;
366 CodeBuffer* cb = dest->outer();
367 addr = new_addr_for(addr0, cb, cb);
368 assert(allow_other_sections || dest->contains2(addr),
369 "addr must be in required section");
370 }
371
372
373 void CallRelocation::set_destination(address x) {
374 pd_set_call_destination(x);
375 }
376
377 void CallRelocation::fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest) {
378 // Usually a self-relative reference to an external routine.
379 // On some platforms, the reference is absolute (not self-relative).
380 // The enhanced use of pd_call_destination sorts this all out.
381 address orig_addr = old_addr_for(addr(), src, dest);
382 address callee = pd_call_destination(orig_addr);
383 // Reassert the callee address, this time in the new copy of the code.
384 pd_set_call_destination(callee);
385 }
386
387
388 #ifdef USE_TRAMPOLINE_STUB_FIX_OWNER
389 void trampoline_stub_Relocation::fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest) {
390 // Finalize owner destination only for nmethods
391 if (dest->blob() != nullptr) return;
392 pd_fix_owner_after_move();
393 }
394 #endif
395
396 //// pack/unpack methods
397
398 void oop_Relocation::pack_data_to(CodeSection* dest) {
399 short* p = (short*) dest->locs_end();
400 p = pack_1_int_to(p, _oop_index);
401 dest->set_locs_end((relocInfo*) p);
402 }
403
404
405 void oop_Relocation::unpack_data() {
406 _oop_index = unpack_1_int();
407 }
408
409 void metadata_Relocation::pack_data_to(CodeSection* dest) {
410 short* p = (short*) dest->locs_end();
411 p = pack_1_int_to(p, _metadata_index);
412 dest->set_locs_end((relocInfo*) p);
413 }
414
415
416 void metadata_Relocation::unpack_data() {
417 _metadata_index = unpack_1_int();
418 }
419
420
421 void virtual_call_Relocation::pack_data_to(CodeSection* dest) {
422 short* p = (short*) dest->locs_end();
423 address point = dest->locs_point();
424
425 normalize_address(_cached_value, dest);
426 jint x0 = scaled_offset_null_special(_cached_value, point);
427 p = pack_2_ints_to(p, x0, _method_index);
428 dest->set_locs_end((relocInfo*) p);
429 }
430
431
432 void virtual_call_Relocation::unpack_data() {
433 jint x0 = 0;
434 unpack_2_ints(x0, _method_index);
435 address point = addr();
436 _cached_value = x0==0? nullptr: address_from_scaled_offset(x0, point);
437 }
438
439 void runtime_call_w_cp_Relocation::pack_data_to(CodeSection * dest) {
440 short* p = pack_1_int_to((short *)dest->locs_end(), (jint)(_offset >> 2));
441 dest->set_locs_end((relocInfo*) p);
442 }
443
444 void runtime_call_w_cp_Relocation::unpack_data() {
445 _offset = unpack_1_int() << 2;
446 }
447
448 void static_stub_Relocation::pack_data_to(CodeSection* dest) {
449 short* p = (short*) dest->locs_end();
450 CodeSection* insts = dest->outer()->insts();
451 normalize_address(_static_call, insts);
452 p = pack_1_int_to(p, scaled_offset(_static_call, insts->start()));
453 dest->set_locs_end((relocInfo*) p);
454 }
455
456 void static_stub_Relocation::unpack_data() {
457 address base = binding()->section_start(CodeBuffer::SECT_INSTS);
458 jint offset = unpack_1_int();
459 _static_call = address_from_scaled_offset(offset, base);
460 }
461
462 void trampoline_stub_Relocation::pack_data_to(CodeSection* dest ) {
463 short* p = (short*) dest->locs_end();
464 CodeSection* insts = dest->outer()->insts();
465 normalize_address(_owner, insts);
466 p = pack_1_int_to(p, scaled_offset(_owner, insts->start()));
467 dest->set_locs_end((relocInfo*) p);
468 }
469
470 void trampoline_stub_Relocation::unpack_data() {
471 address base = binding()->section_start(CodeBuffer::SECT_INSTS);
472 _owner = address_from_scaled_offset(unpack_1_int(), base);
473 }
474
475 void external_word_Relocation::pack_data_to(CodeSection* dest) {
476 short* p = (short*) dest->locs_end();
477 int index = ExternalsRecorder::find_index(_target);
478 // Use 4 bytes to store index to be able patch it when
479 // updating relocations in SCCReader::read_relocations().
480 p = add_jint(p, index);
481 dest->set_locs_end((relocInfo*) p);
482 }
483
484 void external_word_Relocation::unpack_data() {
485 int index = unpack_1_int();
486 _target = ExternalsRecorder::at(index);
487 }
488
489
490 void internal_word_Relocation::pack_data_to(CodeSection* dest) {
491 short* p = (short*) dest->locs_end();
492 normalize_address(_target, dest, true);
493
494 // Check whether my target address is valid within this section.
495 // If not, strengthen the relocation type to point to another section.
496 int sindex = _section;
497 if (sindex == CodeBuffer::SECT_NONE && _target != nullptr
498 && (!dest->allocates(_target) || _target == dest->locs_point())) {
499 sindex = dest->outer()->section_index_of(_target);
500 guarantee(sindex != CodeBuffer::SECT_NONE, "must belong somewhere");
501 relocInfo* base = dest->locs_end() - 1;
502 assert(base->type() == this->type(), "sanity");
503 // Change the written type, to be section_word_type instead.
504 base->set_type(relocInfo::section_word_type);
505 }
506
507 // Note: An internal_word relocation cannot refer to its own instruction,
508 // because we reserve "0" to mean that the pointer itself is embedded
509 // in the code stream. We use a section_word relocation for such cases.
510
511 if (sindex == CodeBuffer::SECT_NONE) {
512 assert(type() == relocInfo::internal_word_type, "must be base class");
513 guarantee(_target == nullptr || dest->allocates2(_target), "must be within the given code section");
514 jint x0 = scaled_offset_null_special(_target, dest->locs_point());
515 assert(!(x0 == 0 && _target != nullptr), "correct encoding of null target");
516 p = pack_1_int_to(p, x0);
517 } else {
518 assert(_target != nullptr, "sanity");
519 CodeSection* sect = dest->outer()->code_section(sindex);
520 guarantee(sect->allocates2(_target), "must be in correct section");
521 address base = sect->start();
522 jint offset = scaled_offset(_target, base);
523 assert((uint)sindex < (uint)CodeBuffer::SECT_LIMIT, "sanity");
524 assert(CodeBuffer::SECT_LIMIT <= (1 << section_width), "section_width++");
525 p = pack_1_int_to(p, (offset << section_width) | sindex);
526 }
527
528 dest->set_locs_end((relocInfo*) p);
529 }
530
531
532 void internal_word_Relocation::unpack_data() {
533 jint x0 = unpack_1_int();
534 _target = x0==0? nullptr: address_from_scaled_offset(x0, addr());
535 _section = CodeBuffer::SECT_NONE;
536 }
537
538
539 void section_word_Relocation::unpack_data() {
540 jint x = unpack_1_int();
541 jint offset = (x >> section_width);
542 int sindex = (x & ((1<<section_width)-1));
543 address base = binding()->section_start(sindex);
544
545 _section = sindex;
546 _target = address_from_scaled_offset(offset, base);
547 }
548
549 //// miscellaneous methods
550 oop* oop_Relocation::oop_addr() {
551 int n = _oop_index;
552 if (n == 0) {
553 // oop is stored in the code stream
554 return (oop*) pd_address_in_code();
555 } else {
556 // oop is stored in table at nmethod::oops_begin
557 return code()->oop_addr_at(n);
558 }
559 }
560
561
562 oop oop_Relocation::oop_value() {
563 // clean inline caches store a special pseudo-null
564 if (Universe::contains_non_oop_word(oop_addr())) {
565 return nullptr;
566 }
567 return *oop_addr();
568 }
569
570
571 void oop_Relocation::fix_oop_relocation() {
572 if (!oop_is_immediate()) {
573 // get the oop from the pool, and re-insert it into the instruction:
574 set_value(value());
575 }
576 }
577
578
579 void oop_Relocation::verify_oop_relocation() {
580 if (!oop_is_immediate()) {
581 // get the oop from the pool, and re-insert it into the instruction:
582 verify_value(value());
583 }
584 }
585
586 // meta data versions
587 Metadata** metadata_Relocation::metadata_addr() {
588 int n = _metadata_index;
589 if (n == 0) {
590 // metadata is stored in the code stream
591 return (Metadata**) pd_address_in_code();
592 } else {
593 // metadata is stored in table at nmethod::metadatas_begin
594 return code()->metadata_addr_at(n);
595 }
596 }
597
598
599 Metadata* metadata_Relocation::metadata_value() {
600 Metadata* v = *metadata_addr();
601 // clean inline caches store a special pseudo-null
602 if (v == (Metadata*)Universe::non_oop_word()) v = nullptr;
603 return v;
604 }
605
606
607 void metadata_Relocation::fix_metadata_relocation() {
608 if (!metadata_is_immediate()) {
609 // get the metadata from the pool, and re-insert it into the instruction:
610 pd_fix_value(value());
611 }
612 }
613
614 address virtual_call_Relocation::cached_value() {
615 assert(_cached_value != nullptr && _cached_value < addr(), "must precede ic_call");
616 return _cached_value;
617 }
618
619 Method* virtual_call_Relocation::method_value() {
620 nmethod* nm = code();
621 if (nm == nullptr) return (Method*)nullptr;
622 Metadata* m = nm->metadata_at(_method_index);
623 assert(m != nullptr || _method_index == 0, "should be non-null for non-zero index");
624 assert(m == nullptr || m->is_method(), "not a method");
625 return (Method*)m;
626 }
627
628 void virtual_call_Relocation::clear_inline_cache() {
629 ResourceMark rm;
630 CompiledIC* icache = CompiledIC_at(this);
631 icache->set_to_clean();
632 }
633
634
635 void opt_virtual_call_Relocation::pack_data_to(CodeSection* dest) {
636 short* p = (short*) dest->locs_end();
637 p = pack_1_int_to(p, _method_index);
638 dest->set_locs_end((relocInfo*) p);
639 }
640
641 void opt_virtual_call_Relocation::unpack_data() {
642 _method_index = unpack_1_int();
643 }
644
645 Method* opt_virtual_call_Relocation::method_value() {
646 nmethod* nm = code();
647 if (nm == nullptr) return (Method*)nullptr;
648 Metadata* m = nm->metadata_at(_method_index);
649 assert(m != nullptr || _method_index == 0, "should be non-null for non-zero index");
650 assert(m == nullptr || m->is_method(), "not a method");
651 return (Method*)m;
652 }
653
654 void opt_virtual_call_Relocation::clear_inline_cache() {
655 ResourceMark rm;
656 CompiledDirectCall* callsite = CompiledDirectCall::at(this);
657 callsite->set_to_clean();
658 }
659
660 address opt_virtual_call_Relocation::static_stub() {
661 // search for the static stub who points back to this static call
662 address static_call_addr = addr();
663 RelocIterator iter(code());
664 while (iter.next()) {
665 if (iter.type() == relocInfo::static_stub_type) {
666 static_stub_Relocation* stub_reloc = iter.static_stub_reloc();
667 if (stub_reloc->static_call() == static_call_addr) {
668 return iter.addr();
669 }
670 }
671 }
672 return nullptr;
673 }
674
675 Method* static_call_Relocation::method_value() {
676 nmethod* nm = code();
677 if (nm == nullptr) return (Method*)nullptr;
678 Metadata* m = nm->metadata_at(_method_index);
679 assert(m != nullptr || _method_index == 0, "should be non-null for non-zero index");
680 assert(m == nullptr || m->is_method(), "not a method");
681 return (Method*)m;
682 }
683
684 void static_call_Relocation::pack_data_to(CodeSection* dest) {
685 short* p = (short*) dest->locs_end();
686 p = pack_1_int_to(p, _method_index);
687 dest->set_locs_end((relocInfo*) p);
688 }
689
690 void static_call_Relocation::unpack_data() {
691 _method_index = unpack_1_int();
692 }
693
694 void static_call_Relocation::clear_inline_cache() {
695 ResourceMark rm;
696 CompiledDirectCall* callsite = CompiledDirectCall::at(this);
697 callsite->set_to_clean();
698 }
699
700
701 address static_call_Relocation::static_stub() {
702 // search for the static stub who points back to this static call
703 address static_call_addr = addr();
704 RelocIterator iter(code());
705 while (iter.next()) {
706 if (iter.type() == relocInfo::static_stub_type) {
707 static_stub_Relocation* stub_reloc = iter.static_stub_reloc();
708 if (stub_reloc->static_call() == static_call_addr) {
709 return iter.addr();
710 }
711 }
712 }
713 return nullptr;
714 }
715
716 // Finds the trampoline address for a call. If no trampoline stub is
717 // found nullptr is returned which can be handled by the caller.
718 address trampoline_stub_Relocation::get_trampoline_for(address call, nmethod* code) {
719 // There are no relocations available when the code gets relocated
720 // because of CodeBuffer expansion.
721 if (code->relocation_size() == 0)
722 return nullptr;
723
724 RelocIterator iter(code, call);
725 while (iter.next()) {
726 if (iter.type() == relocInfo::trampoline_stub_type) {
727 if (iter.trampoline_stub_reloc()->owner() == call) {
728 return iter.addr();
729 }
730 }
731 }
732
733 return nullptr;
734 }
735
736 void static_stub_Relocation::clear_inline_cache() {
737 // Call stub is only used when calling the interpreted code.
738 // It does not really need to be cleared, except that we want to clean out the methodoop.
739 CompiledDirectCall::set_stub_to_clean(this);
740 }
741
742
743 void external_word_Relocation::fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest) {
744 if (_target != nullptr) {
745 // Probably this reference is absolute, not relative, so the following is
746 // probably a no-op.
747 set_value(_target);
748 }
749 // If target is nullptr, this is an absolute embedded reference to an external
750 // location, which means there is nothing to fix here. In either case, the
751 // resulting target should be an "external" address.
752 #ifdef ASSERT
753 if (SCCache::is_on()) {
754 // SCA needs relocation info for card table base which may point to CodeCache
755 if (is_card_table_address(target())) {
756 return;
757 }
758 }
759 #endif
760 postcond(src->section_index_of(target()) == CodeBuffer::SECT_NONE);
761 postcond(dest->section_index_of(target()) == CodeBuffer::SECT_NONE);
762 }
763
764
765 address external_word_Relocation::target() {
766 address target = _target;
767 if (target == nullptr) {
768 target = pd_get_address_from_code();
769 }
770 return target;
771 }
772
773
774 void internal_word_Relocation::fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest) {
775 address target = _target;
776 if (target == nullptr) {
777 target = new_addr_for(this->target(), src, dest);
778 }
779 set_value(target);
780 }
781
782 void internal_word_Relocation::fix_relocation_after_aot_load(address orig_base_addr, address current_base_addr) {
783 address target = _target;
784 if (target == nullptr) {
785 target = this->target();
786 target = current_base_addr + (target - orig_base_addr);
787 }
788 set_value(target);
789 }
790
791 address internal_word_Relocation::target() {
792 address target = _target;
793 if (target == nullptr) {
794 if (addr_in_const()) {
795 target = *(address*)addr();
796 } else {
797 target = pd_get_address_from_code();
798 }
799 }
800 return target;
801 }
802
803 const char* relocInfo::type_name(relocInfo::relocType t) {
804 switch (t) {
805 #define EACH_CASE(name) \
806 case relocInfo::name##_type: \
807 return #name;
808
809 APPLY_TO_RELOCATIONS(EACH_CASE);
810 #undef EACH_CASE
811
812 case relocInfo::none:
813 return "none";
814 case relocInfo::data_prefix_tag:
815 return "prefix";
816 default:
817 return "UNKNOWN RELOC TYPE";
818 }
819 }
820
821
822 void RelocIterator::print_current_on(outputStream* st) {
823 if (!has_current()) {
824 st->print_cr("(no relocs)");
825 return;
826 }
827 st->print("relocInfo@" INTPTR_FORMAT " [type=%d(%s) addr=" INTPTR_FORMAT " offset=%d",
828 p2i(_current), type(), relocInfo::type_name(type()), p2i(_addr), _current->addr_offset());
829 if (current()->format() != 0)
830 st->print(" format=%d", current()->format());
831 if (datalen() == 1) {
832 st->print(" data=%d", data()[0]);
833 } else if (datalen() > 0) {
834 st->print(" data={");
835 for (int i = 0; i < datalen(); i++) {
836 st->print("%04x", data()[i] & 0xFFFF);
837 }
838 st->print("}");
839 }
840 st->print("]");
841 switch (type()) {
842 case relocInfo::oop_type:
843 {
844 oop_Relocation* r = oop_reloc();
845 oop* oop_addr = nullptr;
846 oop raw_oop = nullptr;
847 oop oop_value = nullptr;
848 if (code() != nullptr || r->oop_is_immediate()) {
849 oop_addr = r->oop_addr();
850 raw_oop = *oop_addr;
851 oop_value = r->oop_value();
852 }
853 st->print(" | [oop_addr=" INTPTR_FORMAT " *=" INTPTR_FORMAT " index=%d]",
854 p2i(oop_addr), p2i(raw_oop), r->oop_index());
855 // Do not print the oop by default--we want this routine to
856 // work even during GC or other inconvenient times.
857 if (WizardMode && oop_value != nullptr) {
858 st->print("oop_value=" INTPTR_FORMAT ": ", p2i(oop_value));
859 if (oopDesc::is_oop(oop_value)) {
860 oop_value->print_value_on(st);
861 }
862 }
863 break;
864 }
865 case relocInfo::metadata_type:
866 {
867 metadata_Relocation* r = metadata_reloc();
868 Metadata** metadata_addr = nullptr;
869 Metadata* raw_metadata = nullptr;
870 Metadata* metadata_value = nullptr;
871 if (code() != nullptr || r->metadata_is_immediate()) {
872 metadata_addr = r->metadata_addr();
873 raw_metadata = *metadata_addr;
874 metadata_value = r->metadata_value();
875 }
876 st->print(" | [metadata_addr=" INTPTR_FORMAT " *=" INTPTR_FORMAT " index=%d]",
877 p2i(metadata_addr), p2i(raw_metadata), r->metadata_index());
878 if (metadata_value != nullptr) {
879 st->print("metadata_value=" INTPTR_FORMAT ": ", p2i(metadata_value));
880 metadata_value->print_value_on(st);
881 }
882 break;
883 }
884 case relocInfo::external_word_type:
885 case relocInfo::internal_word_type:
886 case relocInfo::section_word_type:
887 {
888 DataRelocation* r = (DataRelocation*) reloc();
889 st->print(" | [target=" INTPTR_FORMAT "]", p2i(r->value())); //value==target
890 break;
891 }
892 case relocInfo::static_call_type:
893 {
894 static_call_Relocation* r = (static_call_Relocation*) reloc();
895 st->print(" | [destination=" INTPTR_FORMAT " metadata=" INTPTR_FORMAT "]",
896 p2i(r->destination()), p2i(r->method_value()));
897 CodeBlob* cb = CodeCache::find_blob(r->destination());
898 if (cb != nullptr) {
899 st->print(" Blob::%s", cb->name());
900 }
901 break;
902 }
903 case relocInfo::runtime_call_type:
904 case relocInfo::runtime_call_w_cp_type:
905 {
906 CallRelocation* r = (CallRelocation*) reloc();
907 address dest = r->destination();
908 st->print(" | [destination=" INTPTR_FORMAT "]", p2i(dest));
909 if (StubRoutines::contains(dest)) {
910 StubCodeDesc* desc = StubCodeDesc::desc_for(dest);
911 if (desc == nullptr) {
912 desc = StubCodeDesc::desc_for(dest + frame::pc_return_offset);
913 }
914 if (desc != nullptr) {
915 st->print(" Stub::%s", desc->name());
916 }
917 } else {
918 CodeBlob* cb = CodeCache::find_blob(dest);
919 if (cb != nullptr) {
920 st->print(" Blob::%s", cb->name());
921 } else {
922 ResourceMark rm;
923 const int buflen = 1024;
924 char* buf = NEW_RESOURCE_ARRAY(char, buflen);
925 int offset;
926 if (os::dll_address_to_function_name(dest, buf, buflen, &offset)) {
927 st->print(" %s", buf);
928 if (offset != 0) {
929 st->print("+%d", offset);
930 }
931 }
932 }
933 }
934 break;
935 }
936 case relocInfo::virtual_call_type:
937 {
938 virtual_call_Relocation* r = (virtual_call_Relocation*) reloc();
939 st->print(" | [destination=" INTPTR_FORMAT " cached_value=" INTPTR_FORMAT " metadata=" INTPTR_FORMAT "]",
940 p2i(r->destination()), p2i(r->cached_value()), p2i(r->method_value()));
941 CodeBlob* cb = CodeCache::find_blob(r->destination());
942 if (cb != nullptr) {
943 st->print(" Blob::%s", cb->name());
944 }
945 break;
946 }
947 case relocInfo::static_stub_type:
948 {
949 static_stub_Relocation* r = (static_stub_Relocation*) reloc();
950 st->print(" | [static_call=" INTPTR_FORMAT "]", p2i(r->static_call()));
951 break;
952 }
953 case relocInfo::trampoline_stub_type:
954 {
955 trampoline_stub_Relocation* r = (trampoline_stub_Relocation*) reloc();
956 st->print(" | [trampoline owner=" INTPTR_FORMAT "]", p2i(r->owner()));
957 break;
958 }
959 case relocInfo::opt_virtual_call_type:
960 {
961 opt_virtual_call_Relocation* r = (opt_virtual_call_Relocation*) reloc();
962 st->print(" | [destination=" INTPTR_FORMAT " metadata=" INTPTR_FORMAT "]",
963 p2i(r->destination()), p2i(r->method_value()));
964 CodeBlob* cb = CodeCache::find_blob(r->destination());
965 if (cb != nullptr) {
966 st->print(" Blob::%s", cb->name());
967 }
968 break;
969 }
970 default:
971 break;
972 }
973 st->cr();
974 }
975
976
977 void RelocIterator::print_on(outputStream* st) {
978 RelocIterator save_this = (*this);
979 relocInfo* scan = _current;
980 if (!has_current()) scan += 1; // nothing to scan here!
981
982 bool skip_next = has_current();
983 bool got_next;
984 while (true) {
985 got_next = (skip_next || next());
986 skip_next = false;
987
988 st->print(" @" INTPTR_FORMAT ": ", p2i(scan));
989 relocInfo* newscan = _current+1;
990 if (!has_current()) newscan -= 1; // nothing to scan here!
991 while (scan < newscan) {
992 st->print("%04x", *(short*)scan & 0xFFFF);
993 scan++;
994 }
995 st->cr();
996
997 if (!got_next) break;
998 print_current_on(st);
999 }
1000
1001 (*this) = save_this;
1002 }
1003
1004 //---------------------------------------------------------------------------------
1005 // Non-product code
1006
1007 #ifndef PRODUCT
1008
1009 // For the debugger:
1010 extern "C"
1011 void print_blob_locs(nmethod* nm) {
1012 nm->print();
1013 RelocIterator iter(nm);
1014 iter.print_on(tty);
1015 }
1016 extern "C"
1017 void print_buf_locs(CodeBuffer* cb) {
1018 FlagSetting fs(PrintRelocations, true);
1019 cb->print_on(tty);
1020 }
1021 #endif // !PRODUCT