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 #include "oops/oop.inline.hpp"
34
35 PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC
36
37 const RelocationHolder RelocationHolder::none; // its type is relocInfo::none
38
39
40 // Implementation of relocInfo
41
42 #ifdef ASSERT
43 relocInfo::relocInfo(relocType t, int off, int f) {
44 assert(t != data_prefix_tag, "cannot build a prefix this way");
45 assert((t & type_mask) == t, "wrong type");
46 assert((f & format_mask) == f, "wrong format");
47 assert(off >= 0 && off < offset_limit(), "offset out off bounds");
48 assert((off & (offset_unit-1)) == 0, "misaligned offset");
49 (*this) = relocInfo(t, RAW_BITS, off, f);
50 }
51 #endif
52
53 void relocInfo::initialize(CodeSection* dest, Relocation* reloc) {
54 relocInfo* data = this+1; // here's where the data might go
55 dest->set_locs_end(data); // sync end: the next call may read dest.locs_end
56 reloc->pack_data_to(dest); // maybe write data into locs, advancing locs_end
57 relocInfo* data_limit = dest->locs_end();
58 if (data_limit > data) {
59 relocInfo suffix = (*this);
60 data_limit = this->finish_prefix((short*) data_limit);
61 // Finish up with the suffix. (Hack note: pack_data_to might edit this.)
62 *data_limit = suffix;
63 dest->set_locs_end(data_limit+1);
64 }
65 }
66
67 relocInfo* relocInfo::finish_prefix(short* prefix_limit) {
68 assert(sizeof(relocInfo) == sizeof(short), "change this code");
69 short* p = (short*)(this+1);
70 assert(prefix_limit >= p, "must be a valid span of data");
71 int plen = prefix_limit - p;
72 if (plen == 0) {
73 debug_only(_value = 0xFFFF);
74 return this; // no data: remove self completely
75 }
76 if (plen == 1 && fits_into_immediate(p[0])) {
77 (*this) = immediate_relocInfo(p[0]); // move data inside self
78 return this+1;
79 }
80 // cannot compact, so just update the count and return the limit pointer
81 (*this) = prefix_relocInfo(plen); // write new datalen
82 assert(data() + datalen() == prefix_limit, "pointers must line up");
83 return (relocInfo*)prefix_limit;
84 }
85
86
87 void relocInfo::set_type(relocType t) {
88 int old_offset = addr_offset();
89 int old_format = format();
90 (*this) = relocInfo(t, old_offset, old_format);
91 assert(type()==(int)t, "sanity check");
92 assert(addr_offset()==old_offset, "sanity check");
93 assert(format()==old_format, "sanity check");
94 }
95
96
97 void relocInfo::set_format(int f) {
98 int old_offset = addr_offset();
99 assert((f & format_mask) == f, "wrong format");
100 _value = (_value & ~(format_mask << offset_width)) | (f << offset_width);
101 assert(addr_offset()==old_offset, "sanity check");
102 }
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 void relocInfo::remove_reloc_info_for_address(RelocIterator *itr, address pc, relocType old_type) {
119 change_reloc_info_for_address(itr, pc, old_type, none);
120 }
121
122
123 // ----------------------------------------------------------------------------------------------------
124 // Implementation of RelocIterator
125
126 void RelocIterator::initialize(nmethod* nm, address begin, address limit) {
127 initialize_misc();
128
129 if (nm == NULL && begin != NULL) {
130 // allow nmethod to be deduced from beginning address
131 CodeBlob* cb = CodeCache::find_blob(begin);
132 nm = cb->as_nmethod_or_null();
133 }
134 assert(nm != NULL, "must be able to deduce nmethod from other arguments");
135
136 _code = nm;
137 _current = nm->relocation_begin() - 1;
138 _end = nm->relocation_end();
139 _addr = nm->content_begin();
140
141 // Initialize code sections.
142 _section_start[CodeBuffer::SECT_CONSTS] = nm->consts_begin();
143 _section_start[CodeBuffer::SECT_INSTS ] = nm->insts_begin() ;
144 _section_start[CodeBuffer::SECT_STUBS ] = nm->stub_begin() ;
145
146 _section_end [CodeBuffer::SECT_CONSTS] = nm->consts_end() ;
147 _section_end [CodeBuffer::SECT_INSTS ] = nm->insts_end() ;
148 _section_end [CodeBuffer::SECT_STUBS ] = nm->stub_end() ;
149
150 assert(!has_current(), "just checking");
151 assert(begin == NULL || begin >= nm->code_begin(), "in bounds");
152 assert(limit == NULL || limit <= nm->code_end(), "in bounds");
153 set_limits(begin, limit);
154 }
155
156
157 RelocIterator::RelocIterator(CodeSection* cs, address begin, address limit) {
158 initialize_misc();
159
160 _current = cs->locs_start()-1;
161 _end = cs->locs_end();
162 _addr = cs->start();
163 _code = NULL; // Not cb->blob();
164
165 CodeBuffer* cb = cs->outer();
166 assert((int) SECT_LIMIT == CodeBuffer::SECT_LIMIT, "my copy must be equal");
167 for (int n = (int) CodeBuffer::SECT_FIRST; n < (int) CodeBuffer::SECT_LIMIT; n++) {
168 CodeSection* cs = cb->code_section(n);
169 _section_start[n] = cs->start();
170 _section_end [n] = cs->end();
171 }
172
173 assert(!has_current(), "just checking");
174
175 assert(begin == NULL || begin >= cs->start(), "in bounds");
176 assert(limit == NULL || limit <= cs->end(), "in bounds");
177 set_limits(begin, limit);
178 }
179
180
181 enum { indexCardSize = 128 };
182 struct RelocIndexEntry {
183 jint addr_offset; // offset from header_end of an addr()
184 jint reloc_offset; // offset from header_end of a relocInfo (prefix)
185 };
186
187
188 bool RelocIterator::addr_in_const() const {
189 const int n = CodeBuffer::SECT_CONSTS;
190 return section_start(n) <= addr() && addr() < section_end(n);
191 }
192
193
194 static inline int num_cards(int code_size) {
195 return (code_size-1) / indexCardSize;
196 }
197
198
199 int RelocIterator::locs_and_index_size(int code_size, int locs_size) {
200 if (!UseRelocIndex) return locs_size; // no index
201 code_size = round_to(code_size, oopSize);
202 locs_size = round_to(locs_size, oopSize);
203 int index_size = num_cards(code_size) * sizeof(RelocIndexEntry);
204 // format of indexed relocs:
205 // relocation_begin: relocInfo ...
206 // index: (addr,reloc#) ...
207 // indexSize :relocation_end
208 return locs_size + index_size + BytesPerInt;
209 }
210
211
212 void RelocIterator::create_index(relocInfo* dest_begin, int dest_count, relocInfo* dest_end) {
213 address relocation_begin = (address)dest_begin;
214 address relocation_end = (address)dest_end;
215 int total_size = relocation_end - relocation_begin;
216 int locs_size = dest_count * sizeof(relocInfo);
217 if (!UseRelocIndex) {
218 Copy::fill_to_bytes(relocation_begin + locs_size, total_size-locs_size, 0);
219 return;
220 }
221 int index_size = total_size - locs_size - BytesPerInt; // find out how much space is left
222 int ncards = index_size / sizeof(RelocIndexEntry);
223 assert(total_size == locs_size + index_size + BytesPerInt, "checkin'");
224 assert(index_size >= 0 && index_size % sizeof(RelocIndexEntry) == 0, "checkin'");
225 jint* index_size_addr = (jint*)relocation_end - 1;
226
227 assert(sizeof(jint) == BytesPerInt, "change this code");
228
229 *index_size_addr = index_size;
230 if (index_size != 0) {
231 assert(index_size > 0, "checkin'");
232
233 RelocIndexEntry* index = (RelocIndexEntry *)(relocation_begin + locs_size);
234 assert(index == (RelocIndexEntry*)index_size_addr - ncards, "checkin'");
235
236 // walk over the relocations, and fill in index entries as we go
237 RelocIterator iter;
238 const address initial_addr = NULL;
239 relocInfo* const initial_current = dest_begin - 1; // biased by -1 like elsewhere
240
241 iter._code = NULL;
242 iter._addr = initial_addr;
243 iter._limit = (address)(intptr_t)(ncards * indexCardSize);
244 iter._current = initial_current;
245 iter._end = dest_begin + dest_count;
246
247 int i = 0;
248 address next_card_addr = (address)indexCardSize;
249 int addr_offset = 0;
250 int reloc_offset = 0;
251 while (true) {
252 // Checkpoint the iterator before advancing it.
253 addr_offset = iter._addr - initial_addr;
254 reloc_offset = iter._current - initial_current;
255 if (!iter.next()) break;
256 while (iter.addr() >= next_card_addr) {
257 index[i].addr_offset = addr_offset;
258 index[i].reloc_offset = reloc_offset;
259 i++;
260 next_card_addr += indexCardSize;
261 }
262 }
263 while (i < ncards) {
264 index[i].addr_offset = addr_offset;
265 index[i].reloc_offset = reloc_offset;
266 i++;
267 }
268 }
269 }
270
271
272 void RelocIterator::set_limits(address begin, address limit) {
273 int index_size = 0;
274 if (UseRelocIndex && _code != NULL) {
275 index_size = ((jint*)_end)[-1];
276 _end = (relocInfo*)( (address)_end - index_size - BytesPerInt );
277 }
278
279 _limit = limit;
280
281 // the limit affects this next stuff:
282 if (begin != NULL) {
283 #ifdef ASSERT
284 // In ASSERT mode we do not actually use the index, but simply
285 // check that its contents would have led us to the right answer.
286 address addrCheck = _addr;
287 relocInfo* infoCheck = _current;
288 #endif // ASSERT
289 if (index_size > 0) {
290 // skip ahead
291 RelocIndexEntry* index = (RelocIndexEntry*)_end;
292 RelocIndexEntry* index_limit = (RelocIndexEntry*)((address)index + index_size);
293 assert(_addr == _code->code_begin(), "_addr must be unadjusted");
294 int card = (begin - _addr) / indexCardSize;
295 if (card > 0) {
296 if (index+card-1 < index_limit) index += card-1;
297 else index = index_limit - 1;
298 #ifdef ASSERT
299 addrCheck = _addr + index->addr_offset;
300 infoCheck = _current + index->reloc_offset;
301 #else
302 // Advance the iterator immediately to the last valid state
303 // for the previous card. Calling "next" will then advance
304 // it to the first item on the required card.
305 _addr += index->addr_offset;
306 _current += index->reloc_offset;
307 #endif // ASSERT
308 }
309 }
310
311 relocInfo* backup;
312 address backup_addr;
313 while (true) {
314 backup = _current;
315 backup_addr = _addr;
316 #ifdef ASSERT
317 if (backup == infoCheck) {
318 assert(backup_addr == addrCheck, "must match"); addrCheck = NULL; infoCheck = NULL;
319 } else {
320 assert(addrCheck == NULL || backup_addr <= addrCheck, "must not pass addrCheck");
321 }
322 #endif // ASSERT
323 if (!next() || addr() >= begin) break;
324 }
325 assert(addrCheck == NULL || addrCheck == backup_addr, "must have matched addrCheck");
326 assert(infoCheck == NULL || infoCheck == backup, "must have matched infoCheck");
327 // At this point, either we are at the first matching record,
328 // or else there is no such record, and !has_current().
329 // In either case, revert to the immediatly preceding state.
330 _current = backup;
331 _addr = backup_addr;
332 set_has_current(false);
333 }
334 }
335
336
337 void RelocIterator::set_limit(address limit) {
338 address code_end = (address)code() + code()->size();
339 assert(limit == NULL || limit <= code_end, "in bounds");
340 _limit = limit;
341 }
342
343 // All the strange bit-encodings are in here.
344 // The idea is to encode relocation data which are small integers
345 // very efficiently (a single extra halfword). Larger chunks of
346 // relocation data need a halfword header to hold their size.
347 void RelocIterator::advance_over_prefix() {
348 if (_current->is_datalen()) {
349 _data = (short*) _current->data();
350 _datalen = _current->datalen();
351 _current += _datalen + 1; // skip the embedded data & header
352 } else {
353 _databuf = _current->immediate();
354 _data = &_databuf;
355 _datalen = 1;
356 _current++; // skip the header
357 }
358 // The client will see the following relocInfo, whatever that is.
359 // It is the reloc to which the preceding data applies.
360 }
361
362
363 void RelocIterator::initialize_misc() {
364 set_has_current(false);
365 for (int i = (int) CodeBuffer::SECT_FIRST; i < (int) CodeBuffer::SECT_LIMIT; i++) {
366 _section_start[i] = NULL; // these will be lazily computed, if needed
367 _section_end [i] = NULL;
368 }
369 }
370
371
372 Relocation* RelocIterator::reloc() {
373 // (take the "switch" out-of-line)
374 relocInfo::relocType t = type();
375 if (false) {}
376 #define EACH_TYPE(name) \
377 else if (t == relocInfo::name##_type) { \
378 return name##_reloc(); \
379 }
380 APPLY_TO_RELOCATIONS(EACH_TYPE);
381 #undef EACH_TYPE
382 assert(t == relocInfo::none, "must be padding");
383 return new(_rh) Relocation();
384 }
385
386
387 //////// Methods for flyweight Relocation types
388
389
390 RelocationHolder RelocationHolder::plus(int offset) const {
391 if (offset != 0) {
392 switch (type()) {
393 case relocInfo::none:
394 break;
395 case relocInfo::oop_type:
396 {
397 oop_Relocation* r = (oop_Relocation*)reloc();
398 return oop_Relocation::spec(r->oop_index(), r->offset() + offset);
399 }
400 case relocInfo::metadata_type:
401 {
402 metadata_Relocation* r = (metadata_Relocation*)reloc();
403 return metadata_Relocation::spec(r->metadata_index(), r->offset() + offset);
404 }
405 default:
406 ShouldNotReachHere();
407 }
408 }
409 return (*this);
410 }
411
412
413 void Relocation::guarantee_size() {
414 guarantee(false, "Make _relocbuf bigger!");
415 }
416
417 // some relocations can compute their own values
418 address Relocation::value() {
419 ShouldNotReachHere();
420 return NULL;
421 }
422
423
424 void Relocation::set_value(address x) {
425 ShouldNotReachHere();
426 }
427
428 void Relocation::const_set_data_value(address x) {
429 #ifdef _LP64
430 if (format() == relocInfo::narrow_oop_in_const) {
431 *(narrowOop*)addr() = oopDesc::encode_heap_oop((oop) x);
432 } else {
433 #endif
434 *(address*)addr() = x;
435 #ifdef _LP64
436 }
437 #endif
438 }
439
440 void Relocation::const_verify_data_value(address x) {
441 #ifdef _LP64
442 if (format() == relocInfo::narrow_oop_in_const) {
443 assert(*(narrowOop*)addr() == oopDesc::encode_heap_oop((oop) x), "must agree");
444 } else {
445 #endif
446 assert(*(address*)addr() == x, "must agree");
447 #ifdef _LP64
448 }
449 #endif
450 }
451
452
453 RelocationHolder Relocation::spec_simple(relocInfo::relocType rtype) {
454 if (rtype == relocInfo::none) return RelocationHolder::none;
455 relocInfo ri = relocInfo(rtype, 0);
456 RelocIterator itr;
457 itr.set_current(ri);
458 itr.reloc();
459 return itr._rh;
460 }
461
462 int32_t Relocation::runtime_address_to_index(address runtime_address) {
463 assert(!is_reloc_index((intptr_t)runtime_address), "must not look like an index");
464
465 if (runtime_address == NULL) return 0;
466
467 StubCodeDesc* p = StubCodeDesc::desc_for(runtime_address);
468 if (p != NULL && p->begin() == runtime_address) {
469 assert(is_reloc_index(p->index()), "there must not be too many stubs");
470 return (int32_t)p->index();
471 } else {
472 // Known "miscellaneous" non-stub pointers:
473 // os::get_polling_page(), SafepointSynchronize::address_of_state()
474 if (PrintRelocations) {
475 tty->print_cr("random unregistered address in relocInfo: " INTPTR_FORMAT, runtime_address);
476 }
477 #ifndef _LP64
478 return (int32_t) (intptr_t)runtime_address;
479 #else
480 // didn't fit return non-index
481 return -1;
482 #endif /* _LP64 */
483 }
484 }
485
486
487 address Relocation::index_to_runtime_address(int32_t index) {
488 if (index == 0) return NULL;
489
490 if (is_reloc_index(index)) {
491 StubCodeDesc* p = StubCodeDesc::desc_for_index(index);
492 assert(p != NULL, "there must be a stub for this index");
493 return p->begin();
494 } else {
495 #ifndef _LP64
496 // this only works on 32bit machines
497 return (address) ((intptr_t) index);
498 #else
499 fatal("Relocation::index_to_runtime_address, int32_t not pointer sized");
500 return NULL;
501 #endif /* _LP64 */
502 }
503 }
504
505 address Relocation::old_addr_for(address newa,
506 const CodeBuffer* src, CodeBuffer* dest) {
507 int sect = dest->section_index_of(newa);
508 guarantee(sect != CodeBuffer::SECT_NONE, "lost track of this address");
509 address ostart = src->code_section(sect)->start();
510 address nstart = dest->code_section(sect)->start();
511 return ostart + (newa - nstart);
512 }
513
514 address Relocation::new_addr_for(address olda,
515 const CodeBuffer* src, CodeBuffer* dest) {
516 debug_only(const CodeBuffer* src0 = src);
517 int sect = CodeBuffer::SECT_NONE;
518 // Look for olda in the source buffer, and all previous incarnations
519 // if the source buffer has been expanded.
520 for (; src != NULL; src = src->before_expand()) {
521 sect = src->section_index_of(olda);
522 if (sect != CodeBuffer::SECT_NONE) break;
523 }
524 guarantee(sect != CodeBuffer::SECT_NONE, "lost track of this address");
525 address ostart = src->code_section(sect)->start();
526 address nstart = dest->code_section(sect)->start();
527 return nstart + (olda - ostart);
528 }
529
530 void Relocation::normalize_address(address& addr, const CodeSection* dest, bool allow_other_sections) {
531 address addr0 = addr;
532 if (addr0 == NULL || dest->allocates2(addr0)) return;
533 CodeBuffer* cb = dest->outer();
534 addr = new_addr_for(addr0, cb, cb);
535 assert(allow_other_sections || dest->contains2(addr),
536 "addr must be in required section");
537 }
538
539
540 void CallRelocation::set_destination(address x) {
541 pd_set_call_destination(x);
542 }
543
544 void CallRelocation::fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest) {
545 // Usually a self-relative reference to an external routine.
546 // On some platforms, the reference is absolute (not self-relative).
547 // The enhanced use of pd_call_destination sorts this all out.
548 address orig_addr = old_addr_for(addr(), src, dest);
549 address callee = pd_call_destination(orig_addr);
550 // Reassert the callee address, this time in the new copy of the code.
551 pd_set_call_destination(callee);
552 }
553
554
555 //// pack/unpack methods
556
557 void oop_Relocation::pack_data_to(CodeSection* dest) {
558 short* p = (short*) dest->locs_end();
559 p = pack_2_ints_to(p, _oop_index, _offset);
560 dest->set_locs_end((relocInfo*) p);
561 }
562
563
564 void oop_Relocation::unpack_data() {
565 unpack_2_ints(_oop_index, _offset);
566 }
567
568 void metadata_Relocation::pack_data_to(CodeSection* dest) {
569 short* p = (short*) dest->locs_end();
570 p = pack_2_ints_to(p, _metadata_index, _offset);
571 dest->set_locs_end((relocInfo*) p);
572 }
573
574
575 void metadata_Relocation::unpack_data() {
576 unpack_2_ints(_metadata_index, _offset);
577 }
578
579
580 void virtual_call_Relocation::pack_data_to(CodeSection* dest) {
581 short* p = (short*) dest->locs_end();
582 address point = dest->locs_point();
583
584 normalize_address(_cached_value, dest);
585 jint x0 = scaled_offset_null_special(_cached_value, point);
586 p = pack_1_int_to(p, x0);
587 dest->set_locs_end((relocInfo*) p);
588 }
589
590
591 void virtual_call_Relocation::unpack_data() {
592 jint x0 = unpack_1_int();
593 address point = addr();
594 _cached_value = x0==0? NULL: address_from_scaled_offset(x0, point);
595 }
596
597
598 void static_stub_Relocation::pack_data_to(CodeSection* dest) {
599 short* p = (short*) dest->locs_end();
600 CodeSection* insts = dest->outer()->insts();
601 normalize_address(_static_call, insts);
602 p = pack_1_int_to(p, scaled_offset(_static_call, insts->start()));
603 dest->set_locs_end((relocInfo*) p);
604 }
605
606 void static_stub_Relocation::unpack_data() {
607 address base = binding()->section_start(CodeBuffer::SECT_INSTS);
608 jint offset = unpack_1_int();
609 _static_call = address_from_scaled_offset(offset, base);
610 }
611
612 void trampoline_stub_Relocation::pack_data_to(CodeSection* dest ) {
613 short* p = (short*) dest->locs_end();
614 CodeSection* insts = dest->outer()->insts();
615 normalize_address(_owner, insts);
616 p = pack_1_int_to(p, scaled_offset(_owner, insts->start()));
617 dest->set_locs_end((relocInfo*) p);
618 }
619
620 void trampoline_stub_Relocation::unpack_data() {
621 address base = binding()->section_start(CodeBuffer::SECT_INSTS);
622 _owner = address_from_scaled_offset(unpack_1_int(), base);
623 }
624
625 void external_word_Relocation::pack_data_to(CodeSection* dest) {
626 short* p = (short*) dest->locs_end();
627 int32_t index = runtime_address_to_index(_target);
628 #ifndef _LP64
629 p = pack_1_int_to(p, index);
630 #else
631 if (is_reloc_index(index)) {
632 p = pack_2_ints_to(p, index, 0);
633 } else {
634 jlong t = (jlong) _target;
635 int32_t lo = low(t);
636 int32_t hi = high(t);
637 p = pack_2_ints_to(p, lo, hi);
638 DEBUG_ONLY(jlong t1 = jlong_from(hi, lo));
639 assert(!is_reloc_index(t1) && (address) t1 == _target, "not symmetric");
640 }
641 #endif /* _LP64 */
642 dest->set_locs_end((relocInfo*) p);
643 }
644
645
646 void external_word_Relocation::unpack_data() {
647 #ifndef _LP64
648 _target = index_to_runtime_address(unpack_1_int());
649 #else
650 int32_t lo, hi;
651 unpack_2_ints(lo, hi);
652 jlong t = jlong_from(hi, lo);;
653 if (is_reloc_index(t)) {
654 _target = index_to_runtime_address(t);
655 } else {
656 _target = (address) t;
657 }
658 #endif /* _LP64 */
659 }
660
661
662 void internal_word_Relocation::pack_data_to(CodeSection* dest) {
663 short* p = (short*) dest->locs_end();
664 normalize_address(_target, dest, true);
665
666 // Check whether my target address is valid within this section.
667 // If not, strengthen the relocation type to point to another section.
668 int sindex = _section;
669 if (sindex == CodeBuffer::SECT_NONE && _target != NULL
670 && (!dest->allocates(_target) || _target == dest->locs_point())) {
671 sindex = dest->outer()->section_index_of(_target);
672 guarantee(sindex != CodeBuffer::SECT_NONE, "must belong somewhere");
673 relocInfo* base = dest->locs_end() - 1;
674 assert(base->type() == this->type(), "sanity");
675 // Change the written type, to be section_word_type instead.
676 base->set_type(relocInfo::section_word_type);
677 }
678
679 // Note: An internal_word relocation cannot refer to its own instruction,
680 // because we reserve "0" to mean that the pointer itself is embedded
681 // in the code stream. We use a section_word relocation for such cases.
682
683 if (sindex == CodeBuffer::SECT_NONE) {
684 assert(type() == relocInfo::internal_word_type, "must be base class");
685 guarantee(_target == NULL || dest->allocates2(_target), "must be within the given code section");
686 jint x0 = scaled_offset_null_special(_target, dest->locs_point());
687 assert(!(x0 == 0 && _target != NULL), "correct encoding of null target");
688 p = pack_1_int_to(p, x0);
689 } else {
690 assert(_target != NULL, "sanity");
691 CodeSection* sect = dest->outer()->code_section(sindex);
692 guarantee(sect->allocates2(_target), "must be in correct section");
693 address base = sect->start();
694 jint offset = scaled_offset(_target, base);
695 assert((uint)sindex < (uint)CodeBuffer::SECT_LIMIT, "sanity");
696 assert(CodeBuffer::SECT_LIMIT <= (1 << section_width), "section_width++");
697 p = pack_1_int_to(p, (offset << section_width) | sindex);
698 }
699
700 dest->set_locs_end((relocInfo*) p);
701 }
702
703
704 void internal_word_Relocation::unpack_data() {
705 jint x0 = unpack_1_int();
706 _target = x0==0? NULL: address_from_scaled_offset(x0, addr());
707 _section = CodeBuffer::SECT_NONE;
708 }
709
710
711 void section_word_Relocation::unpack_data() {
712 jint x = unpack_1_int();
713 jint offset = (x >> section_width);
714 int sindex = (x & ((1<<section_width)-1));
715 address base = binding()->section_start(sindex);
716
717 _section = sindex;
718 _target = address_from_scaled_offset(offset, base);
719 }
720
721 //// miscellaneous methods
722 oop* oop_Relocation::oop_addr() {
723 int n = _oop_index;
724 if (n == 0) {
725 // oop is stored in the code stream
726 return (oop*) pd_address_in_code();
727 } else {
728 // oop is stored in table at nmethod::oops_begin
729 return code()->oop_addr_at(n);
730 }
731 }
732
733
734 oop oop_Relocation::oop_value() {
735 oop v = *oop_addr();
736 // clean inline caches store a special pseudo-null
737 if (v == (oop)Universe::non_oop_word()) v = NULL;
738 return v;
739 }
740
741
742 void oop_Relocation::fix_oop_relocation() {
743 if (!oop_is_immediate()) {
744 // get the oop from the pool, and re-insert it into the instruction:
745 set_value(value());
746 }
747 }
748
749
750 void oop_Relocation::verify_oop_relocation() {
751 if (!oop_is_immediate()) {
752 // get the oop from the pool, and re-insert it into the instruction:
753 verify_value(value());
754 }
755 }
756
757 // meta data versions
758 Metadata** metadata_Relocation::metadata_addr() {
759 int n = _metadata_index;
760 if (n == 0) {
761 // metadata is stored in the code stream
762 return (Metadata**) pd_address_in_code();
763 } else {
764 // metadata is stored in table at nmethod::metadatas_begin
765 return code()->metadata_addr_at(n);
766 }
767 }
768
769
770 Metadata* metadata_Relocation::metadata_value() {
771 Metadata* v = *metadata_addr();
772 // clean inline caches store a special pseudo-null
773 if (v == (Metadata*)Universe::non_oop_word()) v = NULL;
774 return v;
775 }
776
777
778 void metadata_Relocation::fix_metadata_relocation() {
779 if (!metadata_is_immediate()) {
780 // get the metadata from the pool, and re-insert it into the instruction:
781 pd_fix_value(value());
782 }
783 }
784
785
786 void metadata_Relocation::verify_metadata_relocation() {
787 if (!metadata_is_immediate()) {
788 // get the metadata from the pool, and re-insert it into the instruction:
789 verify_value(value());
790 }
791 }
792
793 address virtual_call_Relocation::cached_value() {
794 assert(_cached_value != NULL && _cached_value < addr(), "must precede ic_call");
795 return _cached_value;
796 }
797
798
799 void virtual_call_Relocation::clear_inline_cache() {
800 // No stubs for ICs
801 // Clean IC
802 ResourceMark rm;
803 CompiledIC* icache = CompiledIC_at(this);
804 icache->set_to_clean();
805 }
806
807
808 void opt_virtual_call_Relocation::clear_inline_cache() {
809 // No stubs for ICs
810 // Clean IC
811 ResourceMark rm;
812 CompiledIC* icache = CompiledIC_at(this);
813 icache->set_to_clean();
814 }
815
816
817 address opt_virtual_call_Relocation::static_stub() {
818 // search for the static stub who points back to this static call
819 address static_call_addr = addr();
820 RelocIterator iter(code());
821 while (iter.next()) {
822 if (iter.type() == relocInfo::static_stub_type) {
823 static_stub_Relocation* stub_reloc = iter.static_stub_reloc();
824 if (stub_reloc->static_call() == static_call_addr) {
825 return iter.addr();
826 }
827 }
828 }
829 return NULL;
830 }
831
832
833 void static_call_Relocation::clear_inline_cache() {
834 // Safe call site info
835 CompiledStaticCall* handler = compiledStaticCall_at(this);
836 handler->set_to_clean();
837 }
838
839
840 address static_call_Relocation::static_stub() {
841 // search for the static stub who points back to this static call
842 address static_call_addr = addr();
843 RelocIterator iter(code());
844 while (iter.next()) {
845 if (iter.type() == relocInfo::static_stub_type) {
846 static_stub_Relocation* stub_reloc = iter.static_stub_reloc();
847 if (stub_reloc->static_call() == static_call_addr) {
848 return iter.addr();
849 }
850 }
851 }
852 return NULL;
853 }
854
855 // Finds the trampoline address for a call. If no trampoline stub is
856 // found NULL is returned which can be handled by the caller.
857 address trampoline_stub_Relocation::get_trampoline_for(address call, nmethod* code) {
858 // There are no relocations available when the code gets relocated
859 // because of CodeBuffer expansion.
860 if (code->relocation_size() == 0)
861 return NULL;
862
863 RelocIterator iter(code, call);
864 while (iter.next()) {
865 if (iter.type() == relocInfo::trampoline_stub_type) {
866 if (iter.trampoline_stub_reloc()->owner() == call) {
867 return iter.addr();
868 }
869 }
870 }
871
872 return NULL;
873 }
874
875 void static_stub_Relocation::clear_inline_cache() {
876 // Call stub is only used when calling the interpreted code.
877 // It does not really need to be cleared, except that we want to clean out the methodoop.
878 CompiledStaticCall::set_stub_to_clean(this);
879 }
880
881
882 void external_word_Relocation::fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest) {
883 address target = _target;
884 if (target == NULL) {
885 // An absolute embedded reference to an external location,
886 // which means there is nothing to fix here.
887 return;
888 }
889 // Probably this reference is absolute, not relative, so the
890 // following is probably a no-op.
891 assert(src->section_index_of(target) == CodeBuffer::SECT_NONE, "sanity");
892 set_value(target);
893 }
894
895
896 address external_word_Relocation::target() {
897 address target = _target;
898 if (target == NULL) {
899 target = pd_get_address_from_code();
900 }
901 return target;
902 }
903
904
905 void internal_word_Relocation::fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest) {
906 address target = _target;
907 if (target == NULL) {
908 target = new_addr_for(this->target(), src, dest);
909 }
910 set_value(target);
911 }
912
913
914 address internal_word_Relocation::target() {
915 address target = _target;
916 if (target == NULL) {
917 if (addr_in_const()) {
918 target = *(address*)addr();
919 } else {
920 target = pd_get_address_from_code();
921 }
922 }
923 return target;
924 }
925
926 //---------------------------------------------------------------------------------
927 // Non-product code
928
929 #ifndef PRODUCT
930
931 static const char* reloc_type_string(relocInfo::relocType t) {
932 switch (t) {
933 #define EACH_CASE(name) \
934 case relocInfo::name##_type: \
935 return #name;
936
937 APPLY_TO_RELOCATIONS(EACH_CASE);
938 #undef EACH_CASE
939
940 case relocInfo::none:
941 return "none";
942 case relocInfo::data_prefix_tag:
943 return "prefix";
944 default:
945 return "UNKNOWN RELOC TYPE";
946 }
947 }
948
949
950 void RelocIterator::print_current() {
951 if (!has_current()) {
952 tty->print_cr("(no relocs)");
953 return;
954 }
955 tty->print("relocInfo@" INTPTR_FORMAT " [type=%d(%s) addr=" INTPTR_FORMAT " offset=%d",
956 _current, type(), reloc_type_string((relocInfo::relocType) type()), _addr, _current->addr_offset());
957 if (current()->format() != 0)
958 tty->print(" format=%d", current()->format());
959 if (datalen() == 1) {
960 tty->print(" data=%d", data()[0]);
961 } else if (datalen() > 0) {
962 tty->print(" data={");
963 for (int i = 0; i < datalen(); i++) {
964 tty->print("%04x", data()[i] & 0xFFFF);
965 }
966 tty->print("}");
967 }
968 tty->print("]");
969 switch (type()) {
970 case relocInfo::oop_type:
971 {
972 oop_Relocation* r = oop_reloc();
973 oop* oop_addr = NULL;
974 oop raw_oop = NULL;
975 oop oop_value = NULL;
976 if (code() != NULL || r->oop_is_immediate()) {
977 oop_addr = r->oop_addr();
978 raw_oop = *oop_addr;
979 oop_value = r->oop_value();
980 }
981 tty->print(" | [oop_addr=" INTPTR_FORMAT " *=" INTPTR_FORMAT " offset=%d]",
982 oop_addr, (address)raw_oop, r->offset());
983 // Do not print the oop by default--we want this routine to
984 // work even during GC or other inconvenient times.
985 if (WizardMode && oop_value != NULL) {
986 tty->print("oop_value=" INTPTR_FORMAT ": ", (address)oop_value);
987 oop_value->print_value_on(tty);
988 }
989 break;
990 }
991 case relocInfo::metadata_type:
992 {
993 metadata_Relocation* r = metadata_reloc();
994 Metadata** metadata_addr = NULL;
995 Metadata* raw_metadata = NULL;
996 Metadata* metadata_value = NULL;
997 if (code() != NULL || r->metadata_is_immediate()) {
998 metadata_addr = r->metadata_addr();
999 raw_metadata = *metadata_addr;
1000 metadata_value = r->metadata_value();
1001 }
1002 tty->print(" | [metadata_addr=" INTPTR_FORMAT " *=" INTPTR_FORMAT " offset=%d]",
1003 metadata_addr, (address)raw_metadata, r->offset());
1004 if (metadata_value != NULL) {
1005 tty->print("metadata_value=" INTPTR_FORMAT ": ", (address)metadata_value);
1006 metadata_value->print_value_on(tty);
1007 }
1008 break;
1009 }
1010 case relocInfo::external_word_type:
1011 case relocInfo::internal_word_type:
1012 case relocInfo::section_word_type:
1013 {
1014 DataRelocation* r = (DataRelocation*) reloc();
1015 tty->print(" | [target=" INTPTR_FORMAT "]", r->value()); //value==target
1016 break;
1017 }
1018 case relocInfo::static_call_type:
1019 case relocInfo::runtime_call_type:
1020 {
1021 CallRelocation* r = (CallRelocation*) reloc();
1022 tty->print(" | [destination=" INTPTR_FORMAT "]", r->destination());
1023 break;
1024 }
1025 case relocInfo::virtual_call_type:
1026 {
1027 virtual_call_Relocation* r = (virtual_call_Relocation*) reloc();
1028 tty->print(" | [destination=" INTPTR_FORMAT " cached_value=" INTPTR_FORMAT "]",
1029 r->destination(), r->cached_value());
1030 break;
1031 }
1032 case relocInfo::static_stub_type:
1033 {
1034 static_stub_Relocation* r = (static_stub_Relocation*) reloc();
1035 tty->print(" | [static_call=" INTPTR_FORMAT "]", r->static_call());
1036 break;
1037 }
1038 case relocInfo::trampoline_stub_type:
1039 {
1040 trampoline_stub_Relocation* r = (trampoline_stub_Relocation*) reloc();
1041 tty->print(" | [trampoline owner=" INTPTR_FORMAT "]", r->owner());
1042 break;
1043 }
1044 }
1045 tty->cr();
1046 }
1047
1048
1049 void RelocIterator::print() {
1050 RelocIterator save_this = (*this);
1051 relocInfo* scan = _current;
1052 if (!has_current()) scan += 1; // nothing to scan here!
1053
1054 bool skip_next = has_current();
1055 bool got_next;
1056 while (true) {
1057 got_next = (skip_next || next());
1058 skip_next = false;
1059
1060 tty->print(" @" INTPTR_FORMAT ": ", scan);
1061 relocInfo* newscan = _current+1;
1062 if (!has_current()) newscan -= 1; // nothing to scan here!
1063 while (scan < newscan) {
1064 tty->print("%04x", *(short*)scan & 0xFFFF);
1065 scan++;
1066 }
1067 tty->cr();
1068
1069 if (!got_next) break;
1070 print_current();
1071 }
1072
1073 (*this) = save_this;
1074 }
1075
1076 // For the debugger:
1077 extern "C"
1078 void print_blob_locs(nmethod* nm) {
1079 nm->print();
1080 RelocIterator iter(nm);
1081 iter.print();
1082 }
1083 extern "C"
1084 void print_buf_locs(CodeBuffer* cb) {
1085 FlagSetting fs(PrintRelocations, true);
1086 cb->print();
1087 }
1088 #endif // !PRODUCT