1 /*
2 * Copyright (c) 1997, 2024, 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 "precompiled.hpp"
26 #include "ci/ciUtilities.hpp"
27 #include "code/codeCache.hpp"
28 #include "code/compiledIC.hpp"
29 #include "code/nmethod.hpp"
30 #include "code/relocInfo.hpp"
31 #include "code/SCCache.hpp"
32 #include "memory/resourceArea.hpp"
33 #include "memory/universe.hpp"
34 #include "oops/compressedOops.inline.hpp"
35 #include "oops/oop.inline.hpp"
36 #include "runtime/flags/flagSetting.hpp"
37 #include "runtime/stubCodeGenerator.hpp"
38 #include "utilities/align.hpp"
39 #include "utilities/checkedCast.hpp"
40 #include "utilities/copy.hpp"
41
42 #include <new>
43 #include <type_traits>
44
45 const RelocationHolder RelocationHolder::none; // its type is relocInfo::none
46
47
48 // Implementation of relocInfo
49
50 #ifdef ASSERT
51 relocInfo::relocType relocInfo::check_relocType(relocType type) {
52 assert(type != data_prefix_tag, "cannot build a prefix this way");
53 assert((type & type_mask) == type, "wrong type");
54 return type;
55 }
56
57 void relocInfo::check_offset_and_format(int offset, int format) {
58 assert(offset >= 0 && offset < offset_limit(), "offset out off bounds");
59 assert(is_aligned(offset, offset_unit), "misaligned offset");
60 assert((format & format_mask) == format, "wrong format");
61 }
62 #endif // ASSERT
63
64 void relocInfo::initialize(CodeSection* dest, Relocation* reloc) {
65 relocInfo* data = this+1; // here's where the data might go
66 dest->set_locs_end(data); // sync end: the next call may read dest.locs_end
67 reloc->pack_data_to(dest); // maybe write data into locs, advancing locs_end
68 relocInfo* data_limit = dest->locs_end();
69 if (data_limit > data) {
70 relocInfo suffix = (*this);
71 data_limit = this->finish_prefix((short*) data_limit);
72 // Finish up with the suffix. (Hack note: pack_data_to might edit this.)
73 *data_limit = suffix;
74 dest->set_locs_end(data_limit+1);
75 }
76 }
77
78 relocInfo* relocInfo::finish_prefix(short* prefix_limit) {
79 assert(sizeof(relocInfo) == sizeof(short), "change this code");
80 short* p = (short*)(this+1);
81 assert(prefix_limit >= p, "must be a valid span of data");
82 int plen = checked_cast<int>(prefix_limit - p);
83 if (plen == 0) {
84 debug_only(_value = 0xFFFF);
85 return this; // no data: remove self completely
86 }
87 if (plen == 1 && fits_into_immediate(p[0])) {
88 (*this) = immediate_relocInfo(p[0]); // move data inside self
89 return this+1;
90 }
91 // cannot compact, so just update the count and return the limit pointer
92 (*this) = prefix_info(plen); // write new datalen
93 assert(data() + datalen() == prefix_limit, "pointers must line up");
94 return (relocInfo*)prefix_limit;
95 }
96
97 void relocInfo::set_type(relocType t) {
98 int old_offset = addr_offset();
99 int old_format = format();
100 (*this) = relocInfo(t, old_offset, old_format);
101 assert(type()==(int)t, "sanity check");
102 assert(addr_offset()==old_offset, "sanity check");
103 assert(format()==old_format, "sanity check");
104 }
105
106 void relocInfo::change_reloc_info_for_address(RelocIterator *itr, address pc, relocType old_type, relocType new_type) {
107 bool found = false;
108 while (itr->next() && !found) {
109 if (itr->addr() == pc) {
110 assert(itr->type()==old_type, "wrong relocInfo type found");
111 itr->current()->set_type(new_type);
112 found=true;
113 }
114 }
115 assert(found, "no relocInfo found for pc");
116 }
117
118
119 // ----------------------------------------------------------------------------------------------------
120 // Implementation of RelocIterator
121
122 void RelocIterator::initialize(nmethod* nm, address begin, address limit) {
123 initialize_misc();
124
125 if (nm == nullptr && begin != nullptr) {
126 // allow nmethod to be deduced from beginning address
127 CodeBlob* cb = CodeCache::find_blob(begin);
128 nm = (cb != nullptr) ? cb->as_nmethod_or_null() : nullptr;
129 }
130 guarantee(nm != nullptr, "must be able to deduce nmethod from other arguments");
131
132 _code = nm;
133 _current = nm->relocation_begin() - 1;
134 _end = nm->relocation_end();
135 _addr = nm->content_begin();
136
137 // Initialize code sections.
138 _section_start[CodeBuffer::SECT_CONSTS] = nm->consts_begin();
139 _section_start[CodeBuffer::SECT_INSTS ] = nm->insts_begin() ;
140 _section_start[CodeBuffer::SECT_STUBS ] = nm->stub_begin() ;
141
142 _section_end [CodeBuffer::SECT_CONSTS] = nm->consts_end() ;
143 _section_end [CodeBuffer::SECT_INSTS ] = nm->insts_end() ;
144 _section_end [CodeBuffer::SECT_STUBS ] = nm->stub_end() ;
145
146 assert(!has_current(), "just checking");
147 assert(begin == nullptr || begin >= nm->code_begin(), "in bounds");
148 assert(limit == nullptr || limit <= nm->code_end(), "in bounds");
149 set_limits(begin, limit);
150 }
151
152
153 RelocIterator::RelocIterator(CodeSection* cs, address begin, address limit) {
154 initialize_misc();
155 assert(((cs->locs_start() != nullptr) && (cs->locs_end() != nullptr)), "valid start and end pointer");
156 _current = cs->locs_start()-1;
157 _end = cs->locs_end();
158 _addr = cs->start();
159 _code = nullptr; // Not cb->blob();
160
161 CodeBuffer* cb = cs->outer();
162 assert((int) SECT_LIMIT == CodeBuffer::SECT_LIMIT, "my copy must be equal");
163 for (int n = (int) CodeBuffer::SECT_FIRST; n < (int) CodeBuffer::SECT_LIMIT; n++) {
164 CodeSection* cs = cb->code_section(n);
165 _section_start[n] = cs->start();
166 _section_end [n] = cs->end();
167 }
168
169 assert(!has_current(), "just checking");
170
171 assert(begin == nullptr || begin >= cs->start(), "in bounds");
172 assert(limit == nullptr || limit <= cs->end(), "in bounds");
173 set_limits(begin, limit);
174 }
175
176 bool RelocIterator::addr_in_const() const {
177 const int n = CodeBuffer::SECT_CONSTS;
178 if (_section_start[n] == nullptr) {
179 return false;
180 }
181 return section_start(n) <= addr() && addr() < section_end(n);
182 }
183
184
185 void RelocIterator::set_limits(address begin, address limit) {
186 _limit = limit;
187
188 // the limit affects this next stuff:
189 if (begin != nullptr) {
190 relocInfo* backup;
191 address backup_addr;
192 while (true) {
193 backup = _current;
194 backup_addr = _addr;
195 if (!next() || addr() >= begin) break;
196 }
197 // At this point, either we are at the first matching record,
198 // or else there is no such record, and !has_current().
199 // In either case, revert to the immediately preceding state.
200 _current = backup;
201 _addr = backup_addr;
202 set_has_current(false);
203 }
204 }
205
206
207 // All the strange bit-encodings are in here.
208 // The idea is to encode relocation data which are small integers
209 // very efficiently (a single extra halfword). Larger chunks of
210 // relocation data need a halfword header to hold their size.
211 void RelocIterator::advance_over_prefix() {
212 if (_current->is_datalen()) {
213 _data = (short*) _current->data();
214 _datalen = _current->datalen();
215 _current += _datalen + 1; // skip the embedded data & header
216 } else {
217 _databuf = _current->immediate();
218 _data = &_databuf;
219 _datalen = 1;
220 _current++; // skip the header
221 }
222 // The client will see the following relocInfo, whatever that is.
223 // It is the reloc to which the preceding data applies.
224 }
225
226
227 void RelocIterator::initialize_misc() {
228 set_has_current(false);
229 for (int i = (int) CodeBuffer::SECT_FIRST; i < (int) CodeBuffer::SECT_LIMIT; i++) {
230 _section_start[i] = nullptr; // these will be lazily computed, if needed
231 _section_end [i] = nullptr;
232 }
233 }
234
235
236 Relocation* RelocIterator::reloc() {
237 // (take the "switch" out-of-line)
238 relocInfo::relocType t = type();
239 if (false) {}
240 #define EACH_TYPE(name) \
241 else if (t == relocInfo::name##_type) { \
242 return name##_reloc(); \
243 }
244 APPLY_TO_RELOCATIONS(EACH_TYPE);
245 #undef EACH_TYPE
246 assert(t == relocInfo::none, "must be padding");
247 _rh = RelocationHolder::none;
248 return _rh.reloc();
249 }
250
251 // Verify all the destructors are trivial, so we don't need to worry about
252 // destroying old contents of a RelocationHolder being assigned or destroyed.
253 #define VERIFY_TRIVIALLY_DESTRUCTIBLE_AUX(Reloc) \
254 static_assert(std::is_trivially_destructible<Reloc>::value, "must be");
255
256 #define VERIFY_TRIVIALLY_DESTRUCTIBLE(name) \
257 VERIFY_TRIVIALLY_DESTRUCTIBLE_AUX(PASTE_TOKENS(name, _Relocation));
258
259 APPLY_TO_RELOCATIONS(VERIFY_TRIVIALLY_DESTRUCTIBLE)
260 VERIFY_TRIVIALLY_DESTRUCTIBLE_AUX(Relocation)
261
262 #undef VERIFY_TRIVIALLY_DESTRUCTIBLE_AUX
263 #undef VERIFY_TRIVIALLY_DESTRUCTIBLE
264
265 // Define all the copy_into functions. These rely on all Relocation types
266 // being trivially destructible (verified above). So it doesn't matter
267 // whether the target holder has been previously initialized or not. There's
268 // no need to consider that distinction and destruct the relocation in an
269 // already initialized holder.
270 #define DEFINE_COPY_INTO_AUX(Reloc) \
271 void Reloc::copy_into(RelocationHolder& holder) const { \
272 copy_into_helper(*this, holder); \
273 }
274
275 #define DEFINE_COPY_INTO(name) \
276 DEFINE_COPY_INTO_AUX(PASTE_TOKENS(name, _Relocation))
277
278 APPLY_TO_RELOCATIONS(DEFINE_COPY_INTO)
279 DEFINE_COPY_INTO_AUX(Relocation)
280
281 #undef DEFINE_COPY_INTO_AUX
282 #undef DEFINE_COPY_INTO
283
284 //////// Methods for flyweight Relocation types
285
286 // some relocations can compute their own values
287 address Relocation::value() {
288 ShouldNotReachHere();
289 return nullptr;
290 }
291
292
293 void Relocation::set_value(address x) {
294 ShouldNotReachHere();
295 }
296
297 void Relocation::const_set_data_value(address x) {
298 #ifdef _LP64
299 if (format() == relocInfo::narrow_oop_in_const) {
300 *(narrowOop*)addr() = CompressedOops::encode(cast_to_oop(x));
301 } else {
302 #endif
303 *(address*)addr() = x;
304 #ifdef _LP64
305 }
306 #endif
307 }
308
309 void Relocation::const_verify_data_value(address x) {
310 #ifdef _LP64
311 if (format() == relocInfo::narrow_oop_in_const) {
312 guarantee(*(narrowOop*)addr() == CompressedOops::encode(cast_to_oop(x)), "must agree");
313 } else {
314 #endif
315 guarantee(*(address*)addr() == x, "must agree");
316 #ifdef _LP64
317 }
318 #endif
319 }
320
321
322 RelocationHolder Relocation::spec_simple(relocInfo::relocType rtype) {
323 if (rtype == relocInfo::none) return RelocationHolder::none;
324 relocInfo ri = relocInfo(rtype, 0);
325 RelocIterator itr;
326 itr.set_current(ri);
327 itr.reloc();
328 return itr._rh;
329 }
330
331 address Relocation::old_addr_for(address newa,
332 const CodeBuffer* src, CodeBuffer* dest) {
333 int sect = dest->section_index_of(newa);
334 guarantee(sect != CodeBuffer::SECT_NONE, "lost track of this address");
335 address ostart = src->code_section(sect)->start();
336 address nstart = dest->code_section(sect)->start();
337 return ostart + (newa - nstart);
338 }
339
340 address Relocation::new_addr_for(address olda,
341 const CodeBuffer* src, CodeBuffer* dest) {
342 debug_only(const CodeBuffer* src0 = src);
343 int sect = CodeBuffer::SECT_NONE;
344 // Look for olda in the source buffer, and all previous incarnations
345 // if the source buffer has been expanded.
346 for (; src != nullptr; src = src->before_expand()) {
347 sect = src->section_index_of(olda);
348 if (sect != CodeBuffer::SECT_NONE) break;
349 }
350 guarantee(sect != CodeBuffer::SECT_NONE, "lost track of this address");
351 address ostart = src->code_section(sect)->start();
352 address nstart = dest->code_section(sect)->start();
353 return nstart + (olda - ostart);
354 }
355
356 void Relocation::normalize_address(address& addr, const CodeSection* dest, bool allow_other_sections) {
357 address addr0 = addr;
358 if (addr0 == nullptr || dest->allocates2(addr0)) return;
359 CodeBuffer* cb = dest->outer();
360 addr = new_addr_for(addr0, cb, cb);
361 assert(allow_other_sections || dest->contains2(addr),
362 "addr must be in required section");
363 }
364
365
366 void CallRelocation::set_destination(address x) {
367 pd_set_call_destination(x);
368 }
369
370 void CallRelocation::fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest) {
371 // Usually a self-relative reference to an external routine.
372 // On some platforms, the reference is absolute (not self-relative).
373 // The enhanced use of pd_call_destination sorts this all out.
374 address orig_addr = old_addr_for(addr(), src, dest);
375 address callee = pd_call_destination(orig_addr);
376 // Reassert the callee address, this time in the new copy of the code.
377 pd_set_call_destination(callee);
378 }
379
380
381 #ifdef USE_TRAMPOLINE_STUB_FIX_OWNER
382 void trampoline_stub_Relocation::fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest) {
383 // Finalize owner destination only for nmethods
384 if (dest->blob() != nullptr) return;
385 pd_fix_owner_after_move();
386 }
387 #endif
388
389 //// pack/unpack methods
390
391 void oop_Relocation::pack_data_to(CodeSection* dest) {
392 short* p = (short*) dest->locs_end();
393 p = pack_1_int_to(p, _oop_index);
394 dest->set_locs_end((relocInfo*) p);
395 }
396
397
398 void oop_Relocation::unpack_data() {
399 _oop_index = unpack_1_int();
400 }
401
402 void metadata_Relocation::pack_data_to(CodeSection* dest) {
403 short* p = (short*) dest->locs_end();
404 p = pack_1_int_to(p, _metadata_index);
405 dest->set_locs_end((relocInfo*) p);
406 }
407
408
409 void metadata_Relocation::unpack_data() {
410 _metadata_index = unpack_1_int();
411 }
412
413
414 void virtual_call_Relocation::pack_data_to(CodeSection* dest) {
415 short* p = (short*) dest->locs_end();
416 address point = dest->locs_point();
417
418 normalize_address(_cached_value, dest);
419 jint x0 = scaled_offset_null_special(_cached_value, point);
420 p = pack_2_ints_to(p, x0, _method_index);
421 dest->set_locs_end((relocInfo*) p);
422 }
423
424
425 void virtual_call_Relocation::unpack_data() {
426 jint x0 = 0;
427 unpack_2_ints(x0, _method_index);
428 address point = addr();
429 _cached_value = x0==0? nullptr: address_from_scaled_offset(x0, point);
430 }
431
432 void runtime_call_w_cp_Relocation::pack_data_to(CodeSection * dest) {
433 short* p = pack_1_int_to((short *)dest->locs_end(), (jint)(_offset >> 2));
434 dest->set_locs_end((relocInfo*) p);
435 }
436
437 void runtime_call_w_cp_Relocation::unpack_data() {
438 _offset = unpack_1_int() << 2;
439 }
440
441 void static_stub_Relocation::pack_data_to(CodeSection* dest) {
442 short* p = (short*) dest->locs_end();
443 CodeSection* insts = dest->outer()->insts();
444 normalize_address(_static_call, insts);
445 p = pack_1_int_to(p, scaled_offset(_static_call, insts->start()));
446 dest->set_locs_end((relocInfo*) p);
447 }
448
449 void static_stub_Relocation::unpack_data() {
450 address base = binding()->section_start(CodeBuffer::SECT_INSTS);
451 jint offset = unpack_1_int();
452 _static_call = address_from_scaled_offset(offset, base);
453 }
454
455 void trampoline_stub_Relocation::pack_data_to(CodeSection* dest ) {
456 short* p = (short*) dest->locs_end();
457 CodeSection* insts = dest->outer()->insts();
458 normalize_address(_owner, insts);
459 p = pack_1_int_to(p, scaled_offset(_owner, insts->start()));
460 dest->set_locs_end((relocInfo*) p);
461 }
462
463 void trampoline_stub_Relocation::unpack_data() {
464 address base = binding()->section_start(CodeBuffer::SECT_INSTS);
465 _owner = address_from_scaled_offset(unpack_1_int(), base);
466 }
467
468 void external_word_Relocation::pack_data_to(CodeSection* dest) {
469 short* p = (short*) dest->locs_end();
470 int index = ExternalsRecorder::find_index(_target);
471 // Use 4 bytes to store index to be able patch it when
472 // updating relocations in SCCReader::read_relocations().
473 p = add_jint(p, index);
474 dest->set_locs_end((relocInfo*) p);
475 }
476
477 void external_word_Relocation::unpack_data() {
478 int index = unpack_1_int();
479 _target = ExternalsRecorder::at(index);
480 }
481
482
483 void internal_word_Relocation::pack_data_to(CodeSection* dest) {
484 short* p = (short*) dest->locs_end();
485 normalize_address(_target, dest, true);
486
487 // Check whether my target address is valid within this section.
488 // If not, strengthen the relocation type to point to another section.
489 int sindex = _section;
490 if (sindex == CodeBuffer::SECT_NONE && _target != nullptr
491 && (!dest->allocates(_target) || _target == dest->locs_point())) {
492 sindex = dest->outer()->section_index_of(_target);
493 guarantee(sindex != CodeBuffer::SECT_NONE, "must belong somewhere");
494 relocInfo* base = dest->locs_end() - 1;
495 assert(base->type() == this->type(), "sanity");
496 // Change the written type, to be section_word_type instead.
497 base->set_type(relocInfo::section_word_type);
498 }
499
500 // Note: An internal_word relocation cannot refer to its own instruction,
501 // because we reserve "0" to mean that the pointer itself is embedded
502 // in the code stream. We use a section_word relocation for such cases.
503
504 if (sindex == CodeBuffer::SECT_NONE) {
505 assert(type() == relocInfo::internal_word_type, "must be base class");
506 guarantee(_target == nullptr || dest->allocates2(_target), "must be within the given code section");
507 jint x0 = scaled_offset_null_special(_target, dest->locs_point());
508 assert(!(x0 == 0 && _target != nullptr), "correct encoding of null target");
509 p = pack_1_int_to(p, x0);
510 } else {
511 assert(_target != nullptr, "sanity");
512 CodeSection* sect = dest->outer()->code_section(sindex);
513 guarantee(sect->allocates2(_target), "must be in correct section");
514 address base = sect->start();
515 jint offset = scaled_offset(_target, base);
516 assert((uint)sindex < (uint)CodeBuffer::SECT_LIMIT, "sanity");
517 assert(CodeBuffer::SECT_LIMIT <= (1 << section_width), "section_width++");
518 p = pack_1_int_to(p, (offset << section_width) | sindex);
519 }
520
521 dest->set_locs_end((relocInfo*) p);
522 }
523
524
525 void internal_word_Relocation::unpack_data() {
526 jint x0 = unpack_1_int();
527 _target = x0==0? nullptr: address_from_scaled_offset(x0, addr());
528 _section = CodeBuffer::SECT_NONE;
529 }
530
531
532 void section_word_Relocation::unpack_data() {
533 jint x = unpack_1_int();
534 jint offset = (x >> section_width);
535 int sindex = (x & ((1<<section_width)-1));
536 address base = binding()->section_start(sindex);
537
538 _section = sindex;
539 _target = address_from_scaled_offset(offset, base);
540 }
541
542 //// miscellaneous methods
543 oop* oop_Relocation::oop_addr() {
544 int n = _oop_index;
545 if (n == 0) {
546 // oop is stored in the code stream
547 return (oop*) pd_address_in_code();
548 } else {
549 // oop is stored in table at nmethod::oops_begin
550 return code()->oop_addr_at(n);
551 }
552 }
553
554
555 oop oop_Relocation::oop_value() {
556 // clean inline caches store a special pseudo-null
557 if (Universe::contains_non_oop_word(oop_addr())) {
558 return nullptr;
559 }
560 return *oop_addr();
561 }
562
563
564 void oop_Relocation::fix_oop_relocation() {
565 if (!oop_is_immediate()) {
566 // get the oop from the pool, and re-insert it into the instruction:
567 set_value(value());
568 }
569 }
570
571
572 void oop_Relocation::verify_oop_relocation() {
573 if (!oop_is_immediate()) {
574 // get the oop from the pool, and re-insert it into the instruction:
575 verify_value(value());
576 }
577 }
578
579 // meta data versions
580 Metadata** metadata_Relocation::metadata_addr() {
581 int n = _metadata_index;
582 if (n == 0) {
583 // metadata is stored in the code stream
584 return (Metadata**) pd_address_in_code();
585 } else {
586 // metadata is stored in table at nmethod::metadatas_begin
587 return code()->metadata_addr_at(n);
588 }
589 }
590
591
592 Metadata* metadata_Relocation::metadata_value() {
593 Metadata* v = *metadata_addr();
594 // clean inline caches store a special pseudo-null
595 if (v == (Metadata*)Universe::non_oop_word()) v = nullptr;
596 return v;
597 }
598
599
600 void metadata_Relocation::fix_metadata_relocation() {
601 if (!metadata_is_immediate()) {
602 // get the metadata from the pool, and re-insert it into the instruction:
603 pd_fix_value(value());
604 }
605 }
606
607 address virtual_call_Relocation::cached_value() {
608 assert(_cached_value != nullptr && _cached_value < addr(), "must precede ic_call");
609 return _cached_value;
610 }
611
612 Method* virtual_call_Relocation::method_value() {
613 nmethod* nm = code();
614 if (nm == nullptr) return (Method*)nullptr;
615 Metadata* m = nm->metadata_at(_method_index);
616 assert(m != nullptr || _method_index == 0, "should be non-null for non-zero index");
617 assert(m == nullptr || m->is_method(), "not a method");
618 return (Method*)m;
619 }
620
621 void virtual_call_Relocation::clear_inline_cache() {
622 ResourceMark rm;
623 CompiledIC* icache = CompiledIC_at(this);
624 icache->set_to_clean();
625 }
626
627
628 void opt_virtual_call_Relocation::pack_data_to(CodeSection* dest) {
629 short* p = (short*) dest->locs_end();
630 p = pack_1_int_to(p, _method_index);
631 dest->set_locs_end((relocInfo*) p);
632 }
633
634 void opt_virtual_call_Relocation::unpack_data() {
635 _method_index = unpack_1_int();
636 }
637
638 Method* opt_virtual_call_Relocation::method_value() {
639 nmethod* nm = code();
640 if (nm == nullptr) return (Method*)nullptr;
641 Metadata* m = nm->metadata_at(_method_index);
642 assert(m != nullptr || _method_index == 0, "should be non-null for non-zero index");
643 assert(m == nullptr || m->is_method(), "not a method");
644 return (Method*)m;
645 }
646
647 void opt_virtual_call_Relocation::clear_inline_cache() {
648 ResourceMark rm;
649 CompiledDirectCall* callsite = CompiledDirectCall::at(this);
650 callsite->set_to_clean();
651 }
652
653 address opt_virtual_call_Relocation::static_stub() {
654 // search for the static stub who points back to this static call
655 address static_call_addr = addr();
656 RelocIterator iter(code());
657 while (iter.next()) {
658 if (iter.type() == relocInfo::static_stub_type) {
659 static_stub_Relocation* stub_reloc = iter.static_stub_reloc();
660 if (stub_reloc->static_call() == static_call_addr) {
661 return iter.addr();
662 }
663 }
664 }
665 return nullptr;
666 }
667
668 Method* static_call_Relocation::method_value() {
669 nmethod* nm = code();
670 if (nm == nullptr) return (Method*)nullptr;
671 Metadata* m = nm->metadata_at(_method_index);
672 assert(m != nullptr || _method_index == 0, "should be non-null for non-zero index");
673 assert(m == nullptr || m->is_method(), "not a method");
674 return (Method*)m;
675 }
676
677 void static_call_Relocation::pack_data_to(CodeSection* dest) {
678 short* p = (short*) dest->locs_end();
679 p = pack_1_int_to(p, _method_index);
680 dest->set_locs_end((relocInfo*) p);
681 }
682
683 void static_call_Relocation::unpack_data() {
684 _method_index = unpack_1_int();
685 }
686
687 void static_call_Relocation::clear_inline_cache() {
688 ResourceMark rm;
689 CompiledDirectCall* callsite = CompiledDirectCall::at(this);
690 callsite->set_to_clean();
691 }
692
693
694 address static_call_Relocation::static_stub() {
695 // search for the static stub who points back to this static call
696 address static_call_addr = addr();
697 RelocIterator iter(code());
698 while (iter.next()) {
699 if (iter.type() == relocInfo::static_stub_type) {
700 static_stub_Relocation* stub_reloc = iter.static_stub_reloc();
701 if (stub_reloc->static_call() == static_call_addr) {
702 return iter.addr();
703 }
704 }
705 }
706 return nullptr;
707 }
708
709 // Finds the trampoline address for a call. If no trampoline stub is
710 // found nullptr is returned which can be handled by the caller.
711 address trampoline_stub_Relocation::get_trampoline_for(address call, nmethod* code) {
712 // There are no relocations available when the code gets relocated
713 // because of CodeBuffer expansion.
714 if (code->relocation_size() == 0)
715 return nullptr;
716
717 RelocIterator iter(code, call);
718 while (iter.next()) {
719 if (iter.type() == relocInfo::trampoline_stub_type) {
720 if (iter.trampoline_stub_reloc()->owner() == call) {
721 return iter.addr();
722 }
723 }
724 }
725
726 return nullptr;
727 }
728
729 void static_stub_Relocation::clear_inline_cache() {
730 // Call stub is only used when calling the interpreted code.
731 // It does not really need to be cleared, except that we want to clean out the methodoop.
732 CompiledDirectCall::set_stub_to_clean(this);
733 }
734
735
736 void external_word_Relocation::fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest) {
737 if (_target != nullptr) {
738 // Probably this reference is absolute, not relative, so the following is
739 // probably a no-op.
740 set_value(_target);
741 }
742 // If target is nullptr, this is an absolute embedded reference to an external
743 // location, which means there is nothing to fix here. In either case, the
744 // resulting target should be an "external" address.
745 #ifdef ASSERT
746 if (SCCache::is_on()) {
747 // SCA needs relocation info for card table base which may point to CodeCache
748 if (is_card_table_address(target())) {
749 return;
750 }
751 }
752 #endif
753 postcond(src->section_index_of(target()) == CodeBuffer::SECT_NONE);
754 postcond(dest->section_index_of(target()) == CodeBuffer::SECT_NONE);
755 }
756
757
758 address external_word_Relocation::target() {
759 address target = _target;
760 if (target == nullptr) {
761 target = pd_get_address_from_code();
762 }
763 return target;
764 }
765
766
767 void internal_word_Relocation::fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest) {
768 address target = _target;
769 if (target == nullptr) {
770 target = new_addr_for(this->target(), src, dest);
771 }
772 set_value(target);
773 }
774
775
776 address internal_word_Relocation::target() {
777 address target = _target;
778 if (target == nullptr) {
779 if (addr_in_const()) {
780 target = *(address*)addr();
781 } else {
782 target = pd_get_address_from_code();
783 }
784 }
785 return target;
786 }
787
788 const char* relocInfo::type_name(relocInfo::relocType t) {
789 switch (t) {
790 #define EACH_CASE(name) \
791 case relocInfo::name##_type: \
792 return #name;
793
794 APPLY_TO_RELOCATIONS(EACH_CASE);
795 #undef EACH_CASE
796
797 case relocInfo::none:
798 return "none";
799 case relocInfo::data_prefix_tag:
800 return "prefix";
801 default:
802 return "UNKNOWN RELOC TYPE";
803 }
804 }
805
806
807 void RelocIterator::print_current_on(outputStream* st) {
808 if (!has_current()) {
809 st->print_cr("(no relocs)");
810 return;
811 }
812 st->print("relocInfo@" INTPTR_FORMAT " [type=%d(%s) addr=" INTPTR_FORMAT " offset=%d",
813 p2i(_current), type(), relocInfo::type_name(type()), p2i(_addr), _current->addr_offset());
814 if (current()->format() != 0)
815 st->print(" format=%d", current()->format());
816 if (datalen() == 1) {
817 st->print(" data=%d", data()[0]);
818 } else if (datalen() > 0) {
819 st->print(" data={");
820 for (int i = 0; i < datalen(); i++) {
821 st->print("%04x", data()[i] & 0xFFFF);
822 }
823 st->print("}");
824 }
825 st->print("]");
826 switch (type()) {
827 case relocInfo::oop_type:
828 {
829 oop_Relocation* r = oop_reloc();
830 oop* oop_addr = nullptr;
831 oop raw_oop = nullptr;
832 oop oop_value = nullptr;
833 if (code() != nullptr || r->oop_is_immediate()) {
834 oop_addr = r->oop_addr();
835 raw_oop = *oop_addr;
836 oop_value = r->oop_value();
837 }
838 st->print(" | [oop_addr=" INTPTR_FORMAT " *=" INTPTR_FORMAT " index=%d]",
839 p2i(oop_addr), p2i(raw_oop), r->oop_index());
840 // Do not print the oop by default--we want this routine to
841 // work even during GC or other inconvenient times.
842 if (WizardMode && oop_value != nullptr) {
843 st->print("oop_value=" INTPTR_FORMAT ": ", p2i(oop_value));
844 if (oopDesc::is_oop(oop_value)) {
845 oop_value->print_value_on(st);
846 }
847 }
848 break;
849 }
850 case relocInfo::metadata_type:
851 {
852 metadata_Relocation* r = metadata_reloc();
853 Metadata** metadata_addr = nullptr;
854 Metadata* raw_metadata = nullptr;
855 Metadata* metadata_value = nullptr;
856 if (code() != nullptr || r->metadata_is_immediate()) {
857 metadata_addr = r->metadata_addr();
858 raw_metadata = *metadata_addr;
859 metadata_value = r->metadata_value();
860 }
861 st->print(" | [metadata_addr=" INTPTR_FORMAT " *=" INTPTR_FORMAT " index=%d]",
862 p2i(metadata_addr), p2i(raw_metadata), r->metadata_index());
863 if (metadata_value != nullptr) {
864 st->print("metadata_value=" INTPTR_FORMAT ": ", p2i(metadata_value));
865 metadata_value->print_value_on(st);
866 }
867 break;
868 }
869 case relocInfo::external_word_type:
870 case relocInfo::internal_word_type:
871 case relocInfo::section_word_type:
872 {
873 DataRelocation* r = (DataRelocation*) reloc();
874 st->print(" | [target=" INTPTR_FORMAT "]", p2i(r->value())); //value==target
875 break;
876 }
877 case relocInfo::static_call_type:
878 {
879 static_call_Relocation* r = (static_call_Relocation*) reloc();
880 st->print(" | [destination=" INTPTR_FORMAT " metadata=" INTPTR_FORMAT "]",
881 p2i(r->destination()), p2i(r->method_value()));
882 CodeBlob* cb = CodeCache::find_blob(r->destination());
883 if (cb != nullptr) {
884 st->print(" Blob::%s", cb->name());
885 }
886 break;
887 }
888 case relocInfo::runtime_call_type:
889 case relocInfo::runtime_call_w_cp_type:
890 {
891 CallRelocation* r = (CallRelocation*) reloc();
892 address dest = r->destination();
893 st->print(" | [destination=" INTPTR_FORMAT "]", p2i(dest));
894 if (StubRoutines::contains(dest)) {
895 StubCodeDesc* desc = StubCodeDesc::desc_for(dest);
896 if (desc == nullptr) {
897 desc = StubCodeDesc::desc_for(dest + frame::pc_return_offset);
898 }
899 if (desc != nullptr) {
900 st->print(" Stub::%s", desc->name());
901 }
902 } else {
903 CodeBlob* cb = CodeCache::find_blob(dest);
904 if (cb != nullptr) {
905 st->print(" Blob::%s", cb->name());
906 } else {
907 ResourceMark rm;
908 const int buflen = 1024;
909 char* buf = NEW_RESOURCE_ARRAY(char, buflen);
910 int offset;
911 if (os::dll_address_to_function_name(dest, buf, buflen, &offset)) {
912 st->print(" %s", buf);
913 if (offset != 0) {
914 st->print("+%d", offset);
915 }
916 }
917 }
918 }
919 break;
920 }
921 case relocInfo::virtual_call_type:
922 {
923 virtual_call_Relocation* r = (virtual_call_Relocation*) reloc();
924 st->print(" | [destination=" INTPTR_FORMAT " cached_value=" INTPTR_FORMAT " metadata=" INTPTR_FORMAT "]",
925 p2i(r->destination()), p2i(r->cached_value()), p2i(r->method_value()));
926 CodeBlob* cb = CodeCache::find_blob(r->destination());
927 if (cb != nullptr) {
928 st->print(" Blob::%s", cb->name());
929 }
930 break;
931 }
932 case relocInfo::static_stub_type:
933 {
934 static_stub_Relocation* r = (static_stub_Relocation*) reloc();
935 st->print(" | [static_call=" INTPTR_FORMAT "]", p2i(r->static_call()));
936 break;
937 }
938 case relocInfo::trampoline_stub_type:
939 {
940 trampoline_stub_Relocation* r = (trampoline_stub_Relocation*) reloc();
941 st->print(" | [trampoline owner=" INTPTR_FORMAT "]", p2i(r->owner()));
942 break;
943 }
944 case relocInfo::opt_virtual_call_type:
945 {
946 opt_virtual_call_Relocation* r = (opt_virtual_call_Relocation*) reloc();
947 st->print(" | [destination=" INTPTR_FORMAT " metadata=" INTPTR_FORMAT "]",
948 p2i(r->destination()), p2i(r->method_value()));
949 CodeBlob* cb = CodeCache::find_blob(r->destination());
950 if (cb != nullptr) {
951 st->print(" Blob::%s", cb->name());
952 }
953 break;
954 }
955 default:
956 break;
957 }
958 st->cr();
959 }
960
961
962 void RelocIterator::print_on(outputStream* st) {
963 RelocIterator save_this = (*this);
964 relocInfo* scan = _current;
965 if (!has_current()) scan += 1; // nothing to scan here!
966
967 bool skip_next = has_current();
968 bool got_next;
969 while (true) {
970 got_next = (skip_next || next());
971 skip_next = false;
972
973 st->print(" @" INTPTR_FORMAT ": ", p2i(scan));
974 relocInfo* newscan = _current+1;
975 if (!has_current()) newscan -= 1; // nothing to scan here!
976 while (scan < newscan) {
977 st->print("%04x", *(short*)scan & 0xFFFF);
978 scan++;
979 }
980 st->cr();
981
982 if (!got_next) break;
983 print_current_on(st);
984 }
985
986 (*this) = save_this;
987 }
988
989 //---------------------------------------------------------------------------------
990 // Non-product code
991
992 #ifndef PRODUCT
993
994 // For the debugger:
995 extern "C"
996 void print_blob_locs(nmethod* nm) {
997 nm->print();
998 RelocIterator iter(nm);
999 iter.print_on(tty);
1000 }
1001 extern "C"
1002 void print_buf_locs(CodeBuffer* cb) {
1003 FlagSetting fs(PrintRelocations, true);
1004 cb->print_on(tty);
1005 }
1006 #endif // !PRODUCT