1 /*
2 * Copyright (c) 1997, 2014, 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 "code/codeCache.hpp"
27 #include "code/compiledIC.hpp"
28 #include "code/nmethod.hpp"
29 #include "code/relocInfo.hpp"
30 #include "memory/resourceArea.hpp"
31 #include "runtime/stubCodeGenerator.hpp"
32 #include "utilities/copy.hpp"
33
34 PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC
35
36 const RelocationHolder RelocationHolder::none; // its type is relocInfo::none
37
38
39 // Implementation of relocInfo
40
41 #ifdef ASSERT
42 relocInfo::relocInfo(relocType t, int off, int f) {
43 assert(t != data_prefix_tag, "cannot build a prefix this way");
44 assert((t & type_mask) == t, "wrong type");
45 assert((f & format_mask) == f, "wrong format");
46 assert(off >= 0 && off < offset_limit(), "offset out off bounds");
47 assert((off & (offset_unit-1)) == 0, "misaligned offset");
48 (*this) = relocInfo(t, RAW_BITS, off, f);
49 }
50 #endif
51
52 void relocInfo::initialize(CodeSection* dest, Relocation* reloc) {
53 relocInfo* data = this+1; // here's where the data might go
54 dest->set_locs_end(data); // sync end: the next call may read dest.locs_end
55 reloc->pack_data_to(dest); // maybe write data into locs, advancing locs_end
56 relocInfo* data_limit = dest->locs_end();
57 if (data_limit > data) {
58 relocInfo suffix = (*this);
59 data_limit = this->finish_prefix((short*) data_limit);
60 // Finish up with the suffix. (Hack note: pack_data_to might edit this.)
61 *data_limit = suffix;
62 dest->set_locs_end(data_limit+1);
63 }
64 }
65
66 relocInfo* relocInfo::finish_prefix(short* prefix_limit) {
67 assert(sizeof(relocInfo) == sizeof(short), "change this code");
68 short* p = (short*)(this+1);
69 assert(prefix_limit >= p, "must be a valid span of data");
70 int plen = prefix_limit - p;
71 if (plen == 0) {
72 debug_only(_value = 0xFFFF);
73 return this; // no data: remove self completely
74 }
75 if (plen == 1 && fits_into_immediate(p[0])) {
76 (*this) = immediate_relocInfo(p[0]); // move data inside self
77 return this+1;
78 }
79 // cannot compact, so just update the count and return the limit pointer
80 (*this) = prefix_relocInfo(plen); // write new datalen
81 assert(data() + datalen() == prefix_limit, "pointers must line up");
82 return (relocInfo*)prefix_limit;
83 }
84
85
86 void relocInfo::set_type(relocType t) {
87 int old_offset = addr_offset();
88 int old_format = format();
89 (*this) = relocInfo(t, old_offset, old_format);
90 assert(type()==(int)t, "sanity check");
91 assert(addr_offset()==old_offset, "sanity check");
92 assert(format()==old_format, "sanity check");
93 }
94
95
96 void relocInfo::set_format(int f) {
97 int old_offset = addr_offset();
98 assert((f & format_mask) == f, "wrong format");
99 _value = (_value & ~(format_mask << offset_width)) | (f << offset_width);
100 assert(addr_offset()==old_offset, "sanity check");
101 }
102
103
104 void relocInfo::change_reloc_info_for_address(RelocIterator *itr, address pc, relocType old_type, relocType new_type) {
105 bool found = false;
106 while (itr->next() && !found) {
107 if (itr->addr() == pc) {
108 assert(itr->type()==old_type, "wrong relocInfo type found");
109 itr->current()->set_type(new_type);
110 found=true;
111 }
112 }
113 assert(found, "no relocInfo found for pc");
114 }
115
116
117 void relocInfo::remove_reloc_info_for_address(RelocIterator *itr, address pc, relocType old_type) {
118 change_reloc_info_for_address(itr, pc, old_type, none);
119 }
120
121
122 // ----------------------------------------------------------------------------------------------------
123 // Implementation of RelocIterator
124
125 void RelocIterator::initialize(nmethod* nm, address begin, address limit) {
126 initialize_misc();
127
128 if (nm == NULL && begin != NULL) {
129 // allow nmethod to be deduced from beginning address
130 CodeBlob* cb = CodeCache::find_blob(begin);
131 nm = cb->as_nmethod_or_null();
132 }
133 assert(nm != NULL, "must be able to deduce nmethod from other arguments");
134
135 _code = nm;
136 _current = nm->relocation_begin() - 1;
137 _end = nm->relocation_end();
138 _addr = nm->content_begin();
139
140 // Initialize code sections.
141 _section_start[CodeBuffer::SECT_CONSTS] = nm->consts_begin();
142 _section_start[CodeBuffer::SECT_INSTS ] = nm->insts_begin() ;
143 _section_start[CodeBuffer::SECT_STUBS ] = nm->stub_begin() ;
144
145 _section_end [CodeBuffer::SECT_CONSTS] = nm->consts_end() ;
146 _section_end [CodeBuffer::SECT_INSTS ] = nm->insts_end() ;
147 _section_end [CodeBuffer::SECT_STUBS ] = nm->stub_end() ;
148
149 assert(!has_current(), "just checking");
150 assert(begin == NULL || begin >= nm->code_begin(), "in bounds");
151 assert(limit == NULL || limit <= nm->code_end(), "in bounds");
152 set_limits(begin, limit);
153 }
154
155
156 RelocIterator::RelocIterator(CodeSection* cs, address begin, address limit) {
157 initialize_misc();
158
159 _current = cs->locs_start()-1;
160 _end = cs->locs_end();
161 _addr = cs->start();
162 _code = NULL; // Not cb->blob();
163
164 CodeBuffer* cb = cs->outer();
165 assert((int) SECT_LIMIT == CodeBuffer::SECT_LIMIT, "my copy must be equal");
166 for (int n = (int) CodeBuffer::SECT_FIRST; n < (int) CodeBuffer::SECT_LIMIT; n++) {
167 CodeSection* cs = cb->code_section(n);
168 _section_start[n] = cs->start();
169 _section_end [n] = cs->end();
170 }
171
172 assert(!has_current(), "just checking");
173
174 assert(begin == NULL || begin >= cs->start(), "in bounds");
175 assert(limit == NULL || limit <= cs->end(), "in bounds");
176 set_limits(begin, limit);
177 }
178
179
180 enum { indexCardSize = 128 };
181 struct RelocIndexEntry {
182 jint addr_offset; // offset from header_end of an addr()
183 jint reloc_offset; // offset from header_end of a relocInfo (prefix)
184 };
185
186
187 bool RelocIterator::addr_in_const() const {
188 const int n = CodeBuffer::SECT_CONSTS;
189 return section_start(n) <= addr() && addr() < section_end(n);
190 }
191
192
193 static inline int num_cards(int code_size) {
194 return (code_size-1) / indexCardSize;
195 }
196
197
198 int RelocIterator::locs_and_index_size(int code_size, int locs_size) {
199 if (!UseRelocIndex) return locs_size; // no index
200 code_size = round_to(code_size, oopSize);
201 locs_size = round_to(locs_size, oopSize);
202 int index_size = num_cards(code_size) * sizeof(RelocIndexEntry);
203 // format of indexed relocs:
204 // relocation_begin: relocInfo ...
205 // index: (addr,reloc#) ...
206 // indexSize :relocation_end
207 return locs_size + index_size + BytesPerInt;
208 }
209
210
211 void RelocIterator::create_index(relocInfo* dest_begin, int dest_count, relocInfo* dest_end) {
212 address relocation_begin = (address)dest_begin;
213 address relocation_end = (address)dest_end;
214 int total_size = relocation_end - relocation_begin;
215 int locs_size = dest_count * sizeof(relocInfo);
216 if (!UseRelocIndex) {
217 Copy::fill_to_bytes(relocation_begin + locs_size, total_size-locs_size, 0);
218 return;
219 }
220 int index_size = total_size - locs_size - BytesPerInt; // find out how much space is left
221 int ncards = index_size / sizeof(RelocIndexEntry);
222 assert(total_size == locs_size + index_size + BytesPerInt, "checkin'");
223 assert(index_size >= 0 && index_size % sizeof(RelocIndexEntry) == 0, "checkin'");
224 jint* index_size_addr = (jint*)relocation_end - 1;
225
226 assert(sizeof(jint) == BytesPerInt, "change this code");
227
228 *index_size_addr = index_size;
229 if (index_size != 0) {
230 assert(index_size > 0, "checkin'");
231
232 RelocIndexEntry* index = (RelocIndexEntry *)(relocation_begin + locs_size);
233 assert(index == (RelocIndexEntry*)index_size_addr - ncards, "checkin'");
234
235 // walk over the relocations, and fill in index entries as we go
236 RelocIterator iter;
237 const address initial_addr = NULL;
238 relocInfo* const initial_current = dest_begin - 1; // biased by -1 like elsewhere
239
240 iter._code = NULL;
241 iter._addr = initial_addr;
242 iter._limit = (address)(intptr_t)(ncards * indexCardSize);
243 iter._current = initial_current;
244 iter._end = dest_begin + dest_count;
245
246 int i = 0;
247 address next_card_addr = (address)indexCardSize;
248 int addr_offset = 0;
249 int reloc_offset = 0;
250 while (true) {
251 // Checkpoint the iterator before advancing it.
252 addr_offset = iter._addr - initial_addr;
253 reloc_offset = iter._current - initial_current;
254 if (!iter.next()) break;
255 while (iter.addr() >= next_card_addr) {
256 index[i].addr_offset = addr_offset;
257 index[i].reloc_offset = reloc_offset;
258 i++;
259 next_card_addr += indexCardSize;
260 }
261 }
262 while (i < ncards) {
263 index[i].addr_offset = addr_offset;
264 index[i].reloc_offset = reloc_offset;
265 i++;
266 }
267 }
268 }
269
270
271 void RelocIterator::set_limits(address begin, address limit) {
272 int index_size = 0;
273 if (UseRelocIndex && _code != NULL) {
274 index_size = ((jint*)_end)[-1];
275 _end = (relocInfo*)( (address)_end - index_size - BytesPerInt );
276 }
277
278 _limit = limit;
279
280 // the limit affects this next stuff:
281 if (begin != NULL) {
282 #ifdef ASSERT
283 // In ASSERT mode we do not actually use the index, but simply
284 // check that its contents would have led us to the right answer.
285 address addrCheck = _addr;
286 relocInfo* infoCheck = _current;
287 #endif // ASSERT
288 if (index_size > 0) {
289 // skip ahead
290 RelocIndexEntry* index = (RelocIndexEntry*)_end;
291 RelocIndexEntry* index_limit = (RelocIndexEntry*)((address)index + index_size);
292 assert(_addr == _code->code_begin(), "_addr must be unadjusted");
293 int card = (begin - _addr) / indexCardSize;
294 if (card > 0) {
295 if (index+card-1 < index_limit) index += card-1;
296 else index = index_limit - 1;
297 #ifdef ASSERT
298 addrCheck = _addr + index->addr_offset;
299 infoCheck = _current + index->reloc_offset;
300 #else
301 // Advance the iterator immediately to the last valid state
302 // for the previous card. Calling "next" will then advance
303 // it to the first item on the required card.
304 _addr += index->addr_offset;
305 _current += index->reloc_offset;
306 #endif // ASSERT
307 }
308 }
309
310 relocInfo* backup;
311 address backup_addr;
312 while (true) {
313 backup = _current;
314 backup_addr = _addr;
315 #ifdef ASSERT
316 if (backup == infoCheck) {
317 assert(backup_addr == addrCheck, "must match"); addrCheck = NULL; infoCheck = NULL;
318 } else {
319 assert(addrCheck == NULL || backup_addr <= addrCheck, "must not pass addrCheck");
320 }
321 #endif // ASSERT
322 if (!next() || addr() >= begin) break;
323 }
324 assert(addrCheck == NULL || addrCheck == backup_addr, "must have matched addrCheck");
325 assert(infoCheck == NULL || infoCheck == backup, "must have matched infoCheck");
326 // At this point, either we are at the first matching record,
327 // or else there is no such record, and !has_current().
328 // In either case, revert to the immediatly preceding state.
329 _current = backup;
330 _addr = backup_addr;
331 set_has_current(false);
332 }
333 }
334
335
336 void RelocIterator::set_limit(address limit) {
337 address code_end = (address)code() + code()->size();
338 assert(limit == NULL || limit <= code_end, "in bounds");
339 _limit = limit;
340 }
341
342 // All the strange bit-encodings are in here.
343 // The idea is to encode relocation data which are small integers
344 // very efficiently (a single extra halfword). Larger chunks of
345 // relocation data need a halfword header to hold their size.
346 void RelocIterator::advance_over_prefix() {
347 if (_current->is_datalen()) {
348 _data = (short*) _current->data();
349 _datalen = _current->datalen();
350 _current += _datalen + 1; // skip the embedded data & header
351 } else {
352 _databuf = _current->immediate();
353 _data = &_databuf;
354 _datalen = 1;
355 _current++; // skip the header
356 }
357 // The client will see the following relocInfo, whatever that is.
358 // It is the reloc to which the preceding data applies.
359 }
360
361
362 void RelocIterator::initialize_misc() {
363 set_has_current(false);
364 for (int i = (int) CodeBuffer::SECT_FIRST; i < (int) CodeBuffer::SECT_LIMIT; i++) {
365 _section_start[i] = NULL; // these will be lazily computed, if needed
366 _section_end [i] = NULL;
367 }
368 }
369
370
371 Relocation* RelocIterator::reloc() {
372 // (take the "switch" out-of-line)
373 relocInfo::relocType t = type();
374 if (false) {}
375 #define EACH_TYPE(name) \
376 else if (t == relocInfo::name##_type) { \
377 return name##_reloc(); \
378 }
379 APPLY_TO_RELOCATIONS(EACH_TYPE);
380 #undef EACH_TYPE
381 assert(t == relocInfo::none, "must be padding");
382 return new(_rh) Relocation();
383 }
384
385
386 //////// Methods for flyweight Relocation types
387
388
389 RelocationHolder RelocationHolder::plus(int offset) const {
390 if (offset != 0) {
391 switch (type()) {
392 case relocInfo::none:
393 break;
394 case relocInfo::oop_type:
395 {
396 oop_Relocation* r = (oop_Relocation*)reloc();
397 return oop_Relocation::spec(r->oop_index(), r->offset() + offset);
398 }
399 case relocInfo::metadata_type:
400 {
401 metadata_Relocation* r = (metadata_Relocation*)reloc();
402 return metadata_Relocation::spec(r->metadata_index(), r->offset() + offset);
403 }
404 default:
405 ShouldNotReachHere();
406 }
407 }
408 return (*this);
409 }
410
411
412 void Relocation::guarantee_size() {
413 guarantee(false, "Make _relocbuf bigger!");
414 }
415
416 // some relocations can compute their own values
417 address Relocation::value() {
418 ShouldNotReachHere();
419 return NULL;
420 }
421
422
423 void Relocation::set_value(address x) {
424 ShouldNotReachHere();
425 }
426
427
428 RelocationHolder Relocation::spec_simple(relocInfo::relocType rtype) {
429 if (rtype == relocInfo::none) return RelocationHolder::none;
430 relocInfo ri = relocInfo(rtype, 0);
431 RelocIterator itr;
432 itr.set_current(ri);
433 itr.reloc();
434 return itr._rh;
435 }
436
437 int32_t Relocation::runtime_address_to_index(address runtime_address) {
438 assert(!is_reloc_index((intptr_t)runtime_address), "must not look like an index");
439
440 if (runtime_address == NULL) return 0;
441
442 StubCodeDesc* p = StubCodeDesc::desc_for(runtime_address);
443 if (p != NULL && p->begin() == runtime_address) {
444 assert(is_reloc_index(p->index()), "there must not be too many stubs");
445 return (int32_t)p->index();
446 } else {
447 // Known "miscellaneous" non-stub pointers:
448 // os::get_polling_page(), SafepointSynchronize::address_of_state()
449 if (PrintRelocations) {
450 tty->print_cr("random unregistered address in relocInfo: " INTPTR_FORMAT, runtime_address);
451 }
452 #ifndef _LP64
453 return (int32_t) (intptr_t)runtime_address;
454 #else
455 // didn't fit return non-index
456 return -1;
457 #endif /* _LP64 */
458 }
459 }
460
461
462 address Relocation::index_to_runtime_address(int32_t index) {
463 if (index == 0) return NULL;
464
465 if (is_reloc_index(index)) {
466 StubCodeDesc* p = StubCodeDesc::desc_for_index(index);
467 assert(p != NULL, "there must be a stub for this index");
468 return p->begin();
469 } else {
470 #ifndef _LP64
471 // this only works on 32bit machines
472 return (address) ((intptr_t) index);
473 #else
474 fatal("Relocation::index_to_runtime_address, int32_t not pointer sized");
475 return NULL;
476 #endif /* _LP64 */
477 }
478 }
479
480 address Relocation::old_addr_for(address newa,
481 const CodeBuffer* src, CodeBuffer* dest) {
482 int sect = dest->section_index_of(newa);
483 guarantee(sect != CodeBuffer::SECT_NONE, "lost track of this address");
484 address ostart = src->code_section(sect)->start();
485 address nstart = dest->code_section(sect)->start();
486 return ostart + (newa - nstart);
487 }
488
489 address Relocation::new_addr_for(address olda,
490 const CodeBuffer* src, CodeBuffer* dest) {
491 debug_only(const CodeBuffer* src0 = src);
492 int sect = CodeBuffer::SECT_NONE;
493 // Look for olda in the source buffer, and all previous incarnations
494 // if the source buffer has been expanded.
495 for (; src != NULL; src = src->before_expand()) {
496 sect = src->section_index_of(olda);
497 if (sect != CodeBuffer::SECT_NONE) break;
498 }
499 guarantee(sect != CodeBuffer::SECT_NONE, "lost track of this address");
500 address ostart = src->code_section(sect)->start();
501 address nstart = dest->code_section(sect)->start();
502 return nstart + (olda - ostart);
503 }
504
505 void Relocation::normalize_address(address& addr, const CodeSection* dest, bool allow_other_sections) {
506 address addr0 = addr;
507 if (addr0 == NULL || dest->allocates2(addr0)) return;
508 CodeBuffer* cb = dest->outer();
509 addr = new_addr_for(addr0, cb, cb);
510 assert(allow_other_sections || dest->contains2(addr),
511 "addr must be in required section");
512 }
513
514
515 void CallRelocation::set_destination(address x) {
516 pd_set_call_destination(x);
517 }
518
519 void CallRelocation::fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest) {
520 // Usually a self-relative reference to an external routine.
521 // On some platforms, the reference is absolute (not self-relative).
522 // The enhanced use of pd_call_destination sorts this all out.
523 address orig_addr = old_addr_for(addr(), src, dest);
524 address callee = pd_call_destination(orig_addr);
525 // Reassert the callee address, this time in the new copy of the code.
526 pd_set_call_destination(callee);
527 }
528
529
530 //// pack/unpack methods
531
532 void oop_Relocation::pack_data_to(CodeSection* dest) {
533 short* p = (short*) dest->locs_end();
534 p = pack_2_ints_to(p, _oop_index, _offset);
535 dest->set_locs_end((relocInfo*) p);
536 }
537
538
539 void oop_Relocation::unpack_data() {
540 unpack_2_ints(_oop_index, _offset);
541 }
542
543 void metadata_Relocation::pack_data_to(CodeSection* dest) {
544 short* p = (short*) dest->locs_end();
545 p = pack_2_ints_to(p, _metadata_index, _offset);
546 dest->set_locs_end((relocInfo*) p);
547 }
548
549
550 void metadata_Relocation::unpack_data() {
551 unpack_2_ints(_metadata_index, _offset);
552 }
553
554
555 void virtual_call_Relocation::pack_data_to(CodeSection* dest) {
556 short* p = (short*) dest->locs_end();
557 address point = dest->locs_point();
558
559 normalize_address(_cached_value, dest);
560 jint x0 = scaled_offset_null_special(_cached_value, point);
561 p = pack_1_int_to(p, x0);
562 dest->set_locs_end((relocInfo*) p);
563 }
564
565
566 void virtual_call_Relocation::unpack_data() {
567 jint x0 = unpack_1_int();
568 address point = addr();
569 _cached_value = x0==0? NULL: address_from_scaled_offset(x0, point);
570 }
571
572
573 void static_stub_Relocation::pack_data_to(CodeSection* dest) {
574 short* p = (short*) dest->locs_end();
575 CodeSection* insts = dest->outer()->insts();
576 normalize_address(_static_call, insts);
577 p = pack_1_int_to(p, scaled_offset(_static_call, insts->start()));
578 dest->set_locs_end((relocInfo*) p);
579 }
580
581 void static_stub_Relocation::unpack_data() {
582 address base = binding()->section_start(CodeBuffer::SECT_INSTS);
583 _static_call = address_from_scaled_offset(unpack_1_int(), base);
584 }
585
586 void trampoline_stub_Relocation::pack_data_to(CodeSection* dest ) {
587 short* p = (short*) dest->locs_end();
588 CodeSection* insts = dest->outer()->insts();
589 normalize_address(_owner, insts);
590 p = pack_1_int_to(p, scaled_offset(_owner, insts->start()));
591 dest->set_locs_end((relocInfo*) p);
592 }
593
594 void trampoline_stub_Relocation::unpack_data() {
595 address base = binding()->section_start(CodeBuffer::SECT_INSTS);
596 _owner = address_from_scaled_offset(unpack_1_int(), base);
597 }
598
599 void external_word_Relocation::pack_data_to(CodeSection* dest) {
600 short* p = (short*) dest->locs_end();
601 int32_t index = runtime_address_to_index(_target);
602 #ifndef _LP64
603 p = pack_1_int_to(p, index);
604 #else
605 if (is_reloc_index(index)) {
606 p = pack_2_ints_to(p, index, 0);
607 } else {
608 jlong t = (jlong) _target;
609 int32_t lo = low(t);
610 int32_t hi = high(t);
611 p = pack_2_ints_to(p, lo, hi);
612 DEBUG_ONLY(jlong t1 = jlong_from(hi, lo));
613 assert(!is_reloc_index(t1) && (address) t1 == _target, "not symmetric");
614 }
615 #endif /* _LP64 */
616 dest->set_locs_end((relocInfo*) p);
617 }
618
619
620 void external_word_Relocation::unpack_data() {
621 #ifndef _LP64
622 _target = index_to_runtime_address(unpack_1_int());
623 #else
624 int32_t lo, hi;
625 unpack_2_ints(lo, hi);
626 jlong t = jlong_from(hi, lo);;
627 if (is_reloc_index(t)) {
628 _target = index_to_runtime_address(t);
629 } else {
630 _target = (address) t;
631 }
632 #endif /* _LP64 */
633 }
634
635
636 void internal_word_Relocation::pack_data_to(CodeSection* dest) {
637 short* p = (short*) dest->locs_end();
638 normalize_address(_target, dest, true);
639
640 // Check whether my target address is valid within this section.
641 // If not, strengthen the relocation type to point to another section.
642 int sindex = _section;
643 if (sindex == CodeBuffer::SECT_NONE && _target != NULL
644 && (!dest->allocates(_target) || _target == dest->locs_point())) {
645 sindex = dest->outer()->section_index_of(_target);
646 guarantee(sindex != CodeBuffer::SECT_NONE, "must belong somewhere");
647 relocInfo* base = dest->locs_end() - 1;
648 assert(base->type() == this->type(), "sanity");
649 // Change the written type, to be section_word_type instead.
650 base->set_type(relocInfo::section_word_type);
651 }
652
653 // Note: An internal_word relocation cannot refer to its own instruction,
654 // because we reserve "0" to mean that the pointer itself is embedded
655 // in the code stream. We use a section_word relocation for such cases.
656
657 if (sindex == CodeBuffer::SECT_NONE) {
658 assert(type() == relocInfo::internal_word_type, "must be base class");
659 guarantee(_target == NULL || dest->allocates2(_target), "must be within the given code section");
660 jint x0 = scaled_offset_null_special(_target, dest->locs_point());
661 assert(!(x0 == 0 && _target != NULL), "correct encoding of null target");
662 p = pack_1_int_to(p, x0);
663 } else {
664 assert(_target != NULL, "sanity");
665 CodeSection* sect = dest->outer()->code_section(sindex);
666 guarantee(sect->allocates2(_target), "must be in correct section");
667 address base = sect->start();
668 jint offset = scaled_offset(_target, base);
669 assert((uint)sindex < (uint)CodeBuffer::SECT_LIMIT, "sanity");
670 assert(CodeBuffer::SECT_LIMIT <= (1 << section_width), "section_width++");
671 p = pack_1_int_to(p, (offset << section_width) | sindex);
672 }
673
674 dest->set_locs_end((relocInfo*) p);
675 }
676
677
678 void internal_word_Relocation::unpack_data() {
679 jint x0 = unpack_1_int();
680 _target = x0==0? NULL: address_from_scaled_offset(x0, addr());
681 _section = CodeBuffer::SECT_NONE;
682 }
683
684
685 void section_word_Relocation::unpack_data() {
686 jint x = unpack_1_int();
687 jint offset = (x >> section_width);
688 int sindex = (x & ((1<<section_width)-1));
689 address base = binding()->section_start(sindex);
690
691 _section = sindex;
692 _target = address_from_scaled_offset(offset, base);
693 }
694
695 //// miscellaneous methods
696 oop* oop_Relocation::oop_addr() {
697 int n = _oop_index;
698 if (n == 0) {
699 // oop is stored in the code stream
700 return (oop*) pd_address_in_code();
701 } else {
702 // oop is stored in table at nmethod::oops_begin
703 return code()->oop_addr_at(n);
704 }
705 }
706
707
708 oop oop_Relocation::oop_value() {
709 oop v = *oop_addr();
710 // clean inline caches store a special pseudo-null
711 if (v == (oop)Universe::non_oop_word()) v = NULL;
712 return v;
713 }
714
715
716 void oop_Relocation::fix_oop_relocation() {
717 if (!oop_is_immediate()) {
718 // get the oop from the pool, and re-insert it into the instruction:
719 set_value(value());
720 }
721 }
722
723
724 void oop_Relocation::verify_oop_relocation() {
725 if (!oop_is_immediate()) {
726 // get the oop from the pool, and re-insert it into the instruction:
727 verify_value(value());
728 }
729 }
730
731 // meta data versions
732 Metadata** metadata_Relocation::metadata_addr() {
733 int n = _metadata_index;
734 if (n == 0) {
735 // metadata is stored in the code stream
736 return (Metadata**) pd_address_in_code();
737 } else {
738 // metadata is stored in table at nmethod::metadatas_begin
739 return code()->metadata_addr_at(n);
740 }
741 }
742
743
744 Metadata* metadata_Relocation::metadata_value() {
745 Metadata* v = *metadata_addr();
746 // clean inline caches store a special pseudo-null
747 if (v == (Metadata*)Universe::non_oop_word()) v = NULL;
748 return v;
749 }
750
751
752 void metadata_Relocation::fix_metadata_relocation() {
753 if (!metadata_is_immediate()) {
754 // get the metadata from the pool, and re-insert it into the instruction:
755 pd_fix_value(value());
756 }
757 }
758
759
760 void metadata_Relocation::verify_metadata_relocation() {
761 if (!metadata_is_immediate()) {
762 // get the metadata from the pool, and re-insert it into the instruction:
763 verify_value(value());
764 }
765 }
766
767 address virtual_call_Relocation::cached_value() {
768 assert(_cached_value != NULL && _cached_value < addr(), "must precede ic_call");
769 return _cached_value;
770 }
771
772
773 void virtual_call_Relocation::clear_inline_cache() {
774 // No stubs for ICs
775 // Clean IC
776 ResourceMark rm;
777 CompiledIC* icache = CompiledIC_at(this);
778 icache->set_to_clean();
779 }
780
781
782 void opt_virtual_call_Relocation::clear_inline_cache() {
783 // No stubs for ICs
784 // Clean IC
785 ResourceMark rm;
786 CompiledIC* icache = CompiledIC_at(this);
787 icache->set_to_clean();
788 }
789
790
791 address opt_virtual_call_Relocation::static_stub() {
792 // search for the static stub who points back to this static call
793 address static_call_addr = addr();
794 RelocIterator iter(code());
795 while (iter.next()) {
796 if (iter.type() == relocInfo::static_stub_type) {
797 if (iter.static_stub_reloc()->static_call() == static_call_addr) {
798 return iter.addr();
799 }
800 }
801 }
802 return NULL;
803 }
804
805
806 void static_call_Relocation::clear_inline_cache() {
807 // Safe call site info
808 CompiledStaticCall* handler = compiledStaticCall_at(this);
809 handler->set_to_clean();
810 }
811
812
813 address static_call_Relocation::static_stub() {
814 // search for the static stub who points back to this static call
815 address static_call_addr = addr();
816 RelocIterator iter(code());
817 while (iter.next()) {
818 if (iter.type() == relocInfo::static_stub_type) {
819 if (iter.static_stub_reloc()->static_call() == static_call_addr) {
820 return iter.addr();
821 }
822 }
823 }
824 return NULL;
825 }
826
827 // Finds the trampoline address for a call. If no trampoline stub is
828 // found NULL is returned which can be handled by the caller.
829 address trampoline_stub_Relocation::get_trampoline_for(address call, nmethod* code) {
830 // There are no relocations available when the code gets relocated
831 // because of CodeBuffer expansion.
832 if (code->relocation_size() == 0)
833 return NULL;
834
835 RelocIterator iter(code, call);
836 while (iter.next()) {
837 if (iter.type() == relocInfo::trampoline_stub_type) {
838 if (iter.trampoline_stub_reloc()->owner() == call) {
839 return iter.addr();
840 }
841 }
842 }
843
844 return NULL;
845 }
846
847 void static_stub_Relocation::clear_inline_cache() {
848 // Call stub is only used when calling the interpreted code.
849 // It does not really need to be cleared, except that we want to clean out the methodoop.
850 CompiledStaticCall::set_stub_to_clean(this);
851 }
852
853
854 void external_word_Relocation::fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest) {
855 address target = _target;
856 if (target == NULL) {
857 // An absolute embedded reference to an external location,
858 // which means there is nothing to fix here.
859 return;
860 }
861 // Probably this reference is absolute, not relative, so the
862 // following is probably a no-op.
863 assert(src->section_index_of(target) == CodeBuffer::SECT_NONE, "sanity");
864 set_value(target);
865 }
866
867
868 address external_word_Relocation::target() {
869 address target = _target;
870 if (target == NULL) {
871 target = pd_get_address_from_code();
872 }
873 return target;
874 }
875
876
877 void internal_word_Relocation::fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest) {
878 address target = _target;
879 if (target == NULL) {
880 target = new_addr_for(this->target(), src, dest);
881 }
882 set_value(target);
883 }
884
885
886 address internal_word_Relocation::target() {
887 address target = _target;
888 if (target == NULL) {
889 if (addr_in_const()) {
890 target = *(address*)addr();
891 } else {
892 target = pd_get_address_from_code();
893 }
894 }
895 return target;
896 }
897
898 //---------------------------------------------------------------------------------
899 // Non-product code
900
901 #ifndef PRODUCT
902
903 static const char* reloc_type_string(relocInfo::relocType t) {
904 switch (t) {
905 #define EACH_CASE(name) \
906 case relocInfo::name##_type: \
907 return #name;
908
909 APPLY_TO_RELOCATIONS(EACH_CASE);
910 #undef EACH_CASE
911
912 case relocInfo::none:
913 return "none";
914 case relocInfo::data_prefix_tag:
915 return "prefix";
916 default:
917 return "UNKNOWN RELOC TYPE";
918 }
919 }
920
921
922 void RelocIterator::print_current() {
923 if (!has_current()) {
924 tty->print_cr("(no relocs)");
925 return;
926 }
927 tty->print("relocInfo@" INTPTR_FORMAT " [type=%d(%s) addr=" INTPTR_FORMAT " offset=%d",
928 _current, type(), reloc_type_string((relocInfo::relocType) type()), _addr, _current->addr_offset());
929 if (current()->format() != 0)
930 tty->print(" format=%d", current()->format());
931 if (datalen() == 1) {
932 tty->print(" data=%d", data()[0]);
933 } else if (datalen() > 0) {
934 tty->print(" data={");
935 for (int i = 0; i < datalen(); i++) {
936 tty->print("%04x", data()[i] & 0xFFFF);
937 }
938 tty->print("}");
939 }
940 tty->print("]");
941 switch (type()) {
942 case relocInfo::oop_type:
943 {
944 oop_Relocation* r = oop_reloc();
945 oop* oop_addr = NULL;
946 oop raw_oop = NULL;
947 oop oop_value = NULL;
948 if (code() != NULL || r->oop_is_immediate()) {
949 oop_addr = r->oop_addr();
950 raw_oop = *oop_addr;
951 oop_value = r->oop_value();
952 }
953 tty->print(" | [oop_addr=" INTPTR_FORMAT " *=" INTPTR_FORMAT " offset=%d]",
954 oop_addr, (address)raw_oop, r->offset());
955 // Do not print the oop by default--we want this routine to
956 // work even during GC or other inconvenient times.
957 if (WizardMode && oop_value != NULL) {
958 tty->print("oop_value=" INTPTR_FORMAT ": ", (address)oop_value);
959 oop_value->print_value_on(tty);
960 }
961 break;
962 }
963 case relocInfo::metadata_type:
964 {
965 metadata_Relocation* r = metadata_reloc();
966 Metadata** metadata_addr = NULL;
967 Metadata* raw_metadata = NULL;
968 Metadata* metadata_value = NULL;
969 if (code() != NULL || r->metadata_is_immediate()) {
970 metadata_addr = r->metadata_addr();
971 raw_metadata = *metadata_addr;
972 metadata_value = r->metadata_value();
973 }
974 tty->print(" | [metadata_addr=" INTPTR_FORMAT " *=" INTPTR_FORMAT " offset=%d]",
975 metadata_addr, (address)raw_metadata, r->offset());
976 if (metadata_value != NULL) {
977 tty->print("metadata_value=" INTPTR_FORMAT ": ", (address)metadata_value);
978 metadata_value->print_value_on(tty);
979 }
980 break;
981 }
982 case relocInfo::external_word_type:
983 case relocInfo::internal_word_type:
984 case relocInfo::section_word_type:
985 {
986 DataRelocation* r = (DataRelocation*) reloc();
987 tty->print(" | [target=" INTPTR_FORMAT "]", r->value()); //value==target
988 break;
989 }
990 case relocInfo::static_call_type:
991 case relocInfo::runtime_call_type:
992 {
993 CallRelocation* r = (CallRelocation*) reloc();
994 tty->print(" | [destination=" INTPTR_FORMAT "]", r->destination());
995 break;
996 }
997 case relocInfo::virtual_call_type:
998 {
999 virtual_call_Relocation* r = (virtual_call_Relocation*) reloc();
1000 tty->print(" | [destination=" INTPTR_FORMAT " cached_value=" INTPTR_FORMAT "]",
1001 r->destination(), r->cached_value());
1002 break;
1003 }
1004 case relocInfo::static_stub_type:
1005 {
1006 static_stub_Relocation* r = (static_stub_Relocation*) reloc();
1007 tty->print(" | [static_call=" INTPTR_FORMAT "]", r->static_call());
1008 break;
1009 }
1010 case relocInfo::trampoline_stub_type:
1011 {
1012 trampoline_stub_Relocation* r = (trampoline_stub_Relocation*) reloc();
1013 tty->print(" | [trampoline owner=" INTPTR_FORMAT "]", r->owner());
1014 break;
1015 }
1016 }
1017 tty->cr();
1018 }
1019
1020
1021 void RelocIterator::print() {
1022 RelocIterator save_this = (*this);
1023 relocInfo* scan = _current;
1024 if (!has_current()) scan += 1; // nothing to scan here!
1025
1026 bool skip_next = has_current();
1027 bool got_next;
1028 while (true) {
1029 got_next = (skip_next || next());
1030 skip_next = false;
1031
1032 tty->print(" @" INTPTR_FORMAT ": ", scan);
1033 relocInfo* newscan = _current+1;
1034 if (!has_current()) newscan -= 1; // nothing to scan here!
1035 while (scan < newscan) {
1036 tty->print("%04x", *(short*)scan & 0xFFFF);
1037 scan++;
1038 }
1039 tty->cr();
1040
1041 if (!got_next) break;
1042 print_current();
1043 }
1044
1045 (*this) = save_this;
1046 }
1047
1048 // For the debugger:
1049 extern "C"
1050 void print_blob_locs(nmethod* nm) {
1051 nm->print();
1052 RelocIterator iter(nm);
1053 iter.print();
1054 }
1055 extern "C"
1056 void print_buf_locs(CodeBuffer* cb) {
1057 FlagSetting fs(PrintRelocations, true);
1058 cb->print();
1059 }
1060 #endif // !PRODUCT