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 const RelocationHolder RelocationHolder::none; // its type is relocInfo::none
36
37
38 // Implementation of relocInfo
39
40 #ifdef ASSERT
41 relocInfo::relocInfo(relocType t, int off, int f) {
42 assert(t != data_prefix_tag, "cannot build a prefix this way");
43 assert((t & type_mask) == t, "wrong type");
44 assert((f & format_mask) == f, "wrong format");
45 assert(off >= 0 && off < offset_limit(), "offset out off bounds");
46 assert((off & (offset_unit-1)) == 0, "misaligned offset");
47 (*this) = relocInfo(t, RAW_BITS, off, f);
48 }
49 #endif
50
51 void relocInfo::initialize(CodeSection* dest, Relocation* reloc) {
52 relocInfo* data = this+1; // here's where the data might go
53 dest->set_locs_end(data); // sync end: the next call may read dest.locs_end
54 reloc->pack_data_to(dest); // maybe write data into locs, advancing locs_end
55 relocInfo* data_limit = dest->locs_end();
56 if (data_limit > data) {
57 relocInfo suffix = (*this);
58 data_limit = this->finish_prefix((short*) data_limit);
59 // Finish up with the suffix. (Hack note: pack_data_to might edit this.)
60 *data_limit = suffix;
61 dest->set_locs_end(data_limit+1);
62 }
63 }
64
65 relocInfo* relocInfo::finish_prefix(short* prefix_limit) {
66 assert(sizeof(relocInfo) == sizeof(short), "change this code");
67 short* p = (short*)(this+1);
68 assert(prefix_limit >= p, "must be a valid span of data");
69 int plen = prefix_limit - p;
70 if (plen == 0) {
71 debug_only(_value = 0xFFFF);
72 return this; // no data: remove self completely
73 }
74 if (plen == 1 && fits_into_immediate(p[0])) {
75 (*this) = immediate_relocInfo(p[0]); // move data inside self
76 return this+1;
77 }
78 // cannot compact, so just update the count and return the limit pointer
79 (*this) = prefix_relocInfo(plen); // write new datalen
80 assert(data() + datalen() == prefix_limit, "pointers must line up");
81 return (relocInfo*)prefix_limit;
82 }
83
84
85 void relocInfo::set_type(relocType t) {
86 int old_offset = addr_offset();
87 int old_format = format();
88 (*this) = relocInfo(t, old_offset, old_format);
89 assert(type()==(int)t, "sanity check");
90 assert(addr_offset()==old_offset, "sanity check");
91 assert(format()==old_format, "sanity check");
92 }
93
94
95 void relocInfo::set_format(int f) {
96 int old_offset = addr_offset();
97 assert((f & format_mask) == f, "wrong format");
98 _value = (_value & ~(format_mask << offset_width)) | (f << offset_width);
99 assert(addr_offset()==old_offset, "sanity check");
100 }
101
102
103 void relocInfo::change_reloc_info_for_address(RelocIterator *itr, address pc, relocType old_type, relocType new_type) {
104 bool found = false;
105 while (itr->next() && !found) {
106 if (itr->addr() == pc) {
107 assert(itr->type()==old_type, "wrong relocInfo type found");
108 itr->current()->set_type(new_type);
109 found=true;
110 }
111 }
112 assert(found, "no relocInfo found for pc");
113 }
114
115
116 void relocInfo::remove_reloc_info_for_address(RelocIterator *itr, address pc, relocType old_type) {
117 change_reloc_info_for_address(itr, pc, old_type, none);
118 }
119
120
121 // ----------------------------------------------------------------------------------------------------
122 // Implementation of RelocIterator
123
124 void RelocIterator::initialize(nmethod* nm, address begin, address limit) {
125 initialize_misc();
126
127 if (nm == NULL && begin != NULL) {
128 // allow nmethod to be deduced from beginning address
129 CodeBlob* cb = CodeCache::find_blob(begin);
130 nm = cb->as_nmethod_or_null();
131 }
132 assert(nm != NULL, "must be able to deduce nmethod from other arguments");
133
134 _code = nm;
135 _current = nm->relocation_begin() - 1;
136 _end = nm->relocation_end();
137 _addr = nm->content_begin();
138
139 // Initialize code sections.
140 _section_start[CodeBuffer::SECT_CONSTS] = nm->consts_begin();
141 _section_start[CodeBuffer::SECT_INSTS ] = nm->insts_begin() ;
142 _section_start[CodeBuffer::SECT_STUBS ] = nm->stub_begin() ;
143
144 _section_end [CodeBuffer::SECT_CONSTS] = nm->consts_end() ;
145 _section_end [CodeBuffer::SECT_INSTS ] = nm->insts_end() ;
146 _section_end [CodeBuffer::SECT_STUBS ] = nm->stub_end() ;
147
148 assert(!has_current(), "just checking");
149 assert(begin == NULL || begin >= nm->code_begin(), "in bounds");
150 assert(limit == NULL || limit <= nm->code_end(), "in bounds");
151 set_limits(begin, limit);
152 }
153
154
155 RelocIterator::RelocIterator(CodeSection* cs, address begin, address limit) {
156 initialize_misc();
157
158 _current = cs->locs_start()-1;
159 _end = cs->locs_end();
160 _addr = cs->start();
161 _code = NULL; // Not cb->blob();
162
163 CodeBuffer* cb = cs->outer();
164 assert((int) SECT_LIMIT == CodeBuffer::SECT_LIMIT, "my copy must be equal");
165 for (int n = (int) CodeBuffer::SECT_FIRST; n < (int) CodeBuffer::SECT_LIMIT; n++) {
166 CodeSection* cs = cb->code_section(n);
167 _section_start[n] = cs->start();
168 _section_end [n] = cs->end();
169 }
170
171 assert(!has_current(), "just checking");
172
173 assert(begin == NULL || begin >= cs->start(), "in bounds");
174 assert(limit == NULL || limit <= cs->end(), "in bounds");
175 set_limits(begin, limit);
176 }
177
178
179 enum { indexCardSize = 128 };
180 struct RelocIndexEntry {
181 jint addr_offset; // offset from header_end of an addr()
182 jint reloc_offset; // offset from header_end of a relocInfo (prefix)
183 };
184
185
186 bool RelocIterator::addr_in_const() const {
187 const int n = CodeBuffer::SECT_CONSTS;
188 return section_start(n) <= addr() && addr() < section_end(n);
189 }
190
191
192 static inline int num_cards(int code_size) {
193 return (code_size-1) / indexCardSize;
194 }
195
196
197 int RelocIterator::locs_and_index_size(int code_size, int locs_size) {
198 if (!UseRelocIndex) return locs_size; // no index
199 code_size = round_to(code_size, oopSize);
200 locs_size = round_to(locs_size, oopSize);
201 int index_size = num_cards(code_size) * sizeof(RelocIndexEntry);
202 // format of indexed relocs:
203 // relocation_begin: relocInfo ...
204 // index: (addr,reloc#) ...
205 // indexSize :relocation_end
206 return locs_size + index_size + BytesPerInt;
207 }
208
209
210 void RelocIterator::create_index(relocInfo* dest_begin, int dest_count, relocInfo* dest_end) {
211 address relocation_begin = (address)dest_begin;
212 address relocation_end = (address)dest_end;
213 int total_size = relocation_end - relocation_begin;
214 int locs_size = dest_count * sizeof(relocInfo);
215 if (!UseRelocIndex) {
216 Copy::fill_to_bytes(relocation_begin + locs_size, total_size-locs_size, 0);
217 return;
218 }
219 int index_size = total_size - locs_size - BytesPerInt; // find out how much space is left
220 int ncards = index_size / sizeof(RelocIndexEntry);
221 assert(total_size == locs_size + index_size + BytesPerInt, "checkin'");
222 assert(index_size >= 0 && index_size % sizeof(RelocIndexEntry) == 0, "checkin'");
223 jint* index_size_addr = (jint*)relocation_end - 1;
224
225 assert(sizeof(jint) == BytesPerInt, "change this code");
226
227 *index_size_addr = index_size;
228 if (index_size != 0) {
229 assert(index_size > 0, "checkin'");
230
231 RelocIndexEntry* index = (RelocIndexEntry *)(relocation_begin + locs_size);
232 assert(index == (RelocIndexEntry*)index_size_addr - ncards, "checkin'");
233
234 // walk over the relocations, and fill in index entries as we go
235 RelocIterator iter;
236 const address initial_addr = NULL;
237 relocInfo* const initial_current = dest_begin - 1; // biased by -1 like elsewhere
238
239 iter._code = NULL;
240 iter._addr = initial_addr;
241 iter._limit = (address)(intptr_t)(ncards * indexCardSize);
242 iter._current = initial_current;
243 iter._end = dest_begin + dest_count;
244
245 int i = 0;
246 address next_card_addr = (address)indexCardSize;
247 int addr_offset = 0;
248 int reloc_offset = 0;
249 while (true) {
250 // Checkpoint the iterator before advancing it.
251 addr_offset = iter._addr - initial_addr;
252 reloc_offset = iter._current - initial_current;
253 if (!iter.next()) break;
254 while (iter.addr() >= next_card_addr) {
255 index[i].addr_offset = addr_offset;
256 index[i].reloc_offset = reloc_offset;
257 i++;
258 next_card_addr += indexCardSize;
259 }
260 }
261 while (i < ncards) {
262 index[i].addr_offset = addr_offset;
263 index[i].reloc_offset = reloc_offset;
264 i++;
265 }
266 }
267 }
268
269
270 void RelocIterator::set_limits(address begin, address limit) {
271 int index_size = 0;
272 if (UseRelocIndex && _code != NULL) {
273 index_size = ((jint*)_end)[-1];
274 _end = (relocInfo*)( (address)_end - index_size - BytesPerInt );
275 }
276
277 _limit = limit;
278
279 // the limit affects this next stuff:
280 if (begin != NULL) {
281 #ifdef ASSERT
282 // In ASSERT mode we do not actually use the index, but simply
283 // check that its contents would have led us to the right answer.
284 address addrCheck = _addr;
285 relocInfo* infoCheck = _current;
286 #endif // ASSERT
287 if (index_size > 0) {
288 // skip ahead
289 RelocIndexEntry* index = (RelocIndexEntry*)_end;
290 RelocIndexEntry* index_limit = (RelocIndexEntry*)((address)index + index_size);
291 assert(_addr == _code->code_begin(), "_addr must be unadjusted");
292 int card = (begin - _addr) / indexCardSize;
293 if (card > 0) {
294 if (index+card-1 < index_limit) index += card-1;
295 else index = index_limit - 1;
296 #ifdef ASSERT
297 addrCheck = _addr + index->addr_offset;
298 infoCheck = _current + index->reloc_offset;
299 #else
300 // Advance the iterator immediately to the last valid state
301 // for the previous card. Calling "next" will then advance
302 // it to the first item on the required card.
303 _addr += index->addr_offset;
304 _current += index->reloc_offset;
305 #endif // ASSERT
306 }
307 }
308
309 relocInfo* backup;
310 address backup_addr;
311 while (true) {
312 backup = _current;
313 backup_addr = _addr;
314 #ifdef ASSERT
315 if (backup == infoCheck) {
316 assert(backup_addr == addrCheck, "must match"); addrCheck = NULL; infoCheck = NULL;
317 } else {
318 assert(addrCheck == NULL || backup_addr <= addrCheck, "must not pass addrCheck");
319 }
320 #endif // ASSERT
321 if (!next() || addr() >= begin) break;
322 }
323 assert(addrCheck == NULL || addrCheck == backup_addr, "must have matched addrCheck");
324 assert(infoCheck == NULL || infoCheck == backup, "must have matched infoCheck");
325 // At this point, either we are at the first matching record,
326 // or else there is no such record, and !has_current().
327 // In either case, revert to the immediatly preceding state.
328 _current = backup;
329 _addr = backup_addr;
330 set_has_current(false);
331 }
332 }
333
334
335 void RelocIterator::set_limit(address limit) {
336 address code_end = (address)code() + code()->size();
337 assert(limit == NULL || limit <= code_end, "in bounds");
338 _limit = limit;
339 }
340
341 // All the strange bit-encodings are in here.
342 // The idea is to encode relocation data which are small integers
343 // very efficiently (a single extra halfword). Larger chunks of
344 // relocation data need a halfword header to hold their size.
345 void RelocIterator::advance_over_prefix() {
346 if (_current->is_datalen()) {
347 _data = (short*) _current->data();
348 _datalen = _current->datalen();
349 _current += _datalen + 1; // skip the embedded data & header
350 } else {
351 _databuf = _current->immediate();
352 _data = &_databuf;
353 _datalen = 1;
354 _current++; // skip the header
355 }
356 // The client will see the following relocInfo, whatever that is.
357 // It is the reloc to which the preceding data applies.
358 }
359
360
361 void RelocIterator::initialize_misc() {
362 set_has_current(false);
363 for (int i = (int) CodeBuffer::SECT_FIRST; i < (int) CodeBuffer::SECT_LIMIT; i++) {
364 _section_start[i] = NULL; // these will be lazily computed, if needed
365 _section_end [i] = NULL;
366 }
367 }
368
369
370 Relocation* RelocIterator::reloc() {
371 // (take the "switch" out-of-line)
372 relocInfo::relocType t = type();
373 if (false) {}
374 #define EACH_TYPE(name) \
375 else if (t == relocInfo::name##_type) { \
376 return name##_reloc(); \
377 }
378 APPLY_TO_RELOCATIONS(EACH_TYPE);
379 #undef EACH_TYPE
380 assert(t == relocInfo::none, "must be padding");
381 return new(_rh) Relocation();
382 }
383
384
385 //////// Methods for flyweight Relocation types
386
387
388 RelocationHolder RelocationHolder::plus(int offset) const {
389 if (offset != 0) {
390 switch (type()) {
391 case relocInfo::none:
392 break;
393 case relocInfo::oop_type:
394 {
395 oop_Relocation* r = (oop_Relocation*)reloc();
396 return oop_Relocation::spec(r->oop_index(), r->offset() + offset);
397 }
398 case relocInfo::metadata_type:
399 {
400 metadata_Relocation* r = (metadata_Relocation*)reloc();
401 return metadata_Relocation::spec(r->metadata_index(), r->offset() + offset);
402 }
403 default:
404 ShouldNotReachHere();
405 }
406 }
407 return (*this);
408 }
409
410
411 void Relocation::guarantee_size() {
412 guarantee(false, "Make _relocbuf bigger!");
413 }
414
415 // some relocations can compute their own values
416 address Relocation::value() {
417 ShouldNotReachHere();
418 return NULL;
419 }
420
421
422 void Relocation::set_value(address x) {
423 ShouldNotReachHere();
424 }
425
426 void Relocation::const_set_data_value(address x) {
427 #ifdef _LP64
428 if (format() == relocInfo::narrow_oop_in_const) {
429 *(narrowOop*)addr() = oopDesc::encode_heap_oop((oop) x);
430 } else {
431 #endif
432 *(address*)addr() = x;
433 #ifdef _LP64
434 }
435 #endif
436 }
437
438 void Relocation::const_verify_data_value(address x) {
439 #ifdef _LP64
440 if (format() == relocInfo::narrow_oop_in_const) {
441 guarantee(*(narrowOop*)addr() == oopDesc::encode_heap_oop((oop) x), "must agree");
442 } else {
443 #endif
444 guarantee(*(address*)addr() == x, "must agree");
445 #ifdef _LP64
446 }
447 #endif
448 }
449
450
451 RelocationHolder Relocation::spec_simple(relocInfo::relocType rtype) {
452 if (rtype == relocInfo::none) return RelocationHolder::none;
453 relocInfo ri = relocInfo(rtype, 0);
454 RelocIterator itr;
455 itr.set_current(ri);
456 itr.reloc();
457 return itr._rh;
458 }
459
460 int32_t Relocation::runtime_address_to_index(address runtime_address) {
461 assert(!is_reloc_index((intptr_t)runtime_address), "must not look like an index");
462
463 if (runtime_address == NULL) return 0;
464
465 StubCodeDesc* p = StubCodeDesc::desc_for(runtime_address);
466 if (p != NULL && p->begin() == runtime_address) {
467 assert(is_reloc_index(p->index()), "there must not be too many stubs");
468 return (int32_t)p->index();
469 } else {
470 // Known "miscellaneous" non-stub pointers:
471 // os::get_polling_page(), SafepointSynchronize::address_of_state()
472 if (PrintRelocations) {
473 tty->print_cr("random unregistered address in relocInfo: " INTPTR_FORMAT, p2i(runtime_address));
474 }
475 #ifndef _LP64
476 return (int32_t) (intptr_t)runtime_address;
477 #else
478 // didn't fit return non-index
479 return -1;
480 #endif /* _LP64 */
481 }
482 }
483
484
485 address Relocation::index_to_runtime_address(int32_t index) {
486 if (index == 0) return NULL;
487
488 if (is_reloc_index(index)) {
489 StubCodeDesc* p = StubCodeDesc::desc_for_index(index);
490 assert(p != NULL, "there must be a stub for this index");
491 return p->begin();
492 } else {
493 #ifndef _LP64
494 // this only works on 32bit machines
495 return (address) ((intptr_t) index);
496 #else
497 fatal("Relocation::index_to_runtime_address, int32_t not pointer sized");
498 return NULL;
499 #endif /* _LP64 */
500 }
501 }
502
503 address Relocation::old_addr_for(address newa,
504 const CodeBuffer* src, CodeBuffer* dest) {
505 int sect = dest->section_index_of(newa);
506 guarantee(sect != CodeBuffer::SECT_NONE, "lost track of this address");
507 address ostart = src->code_section(sect)->start();
508 address nstart = dest->code_section(sect)->start();
509 return ostart + (newa - nstart);
510 }
511
512 address Relocation::new_addr_for(address olda,
513 const CodeBuffer* src, CodeBuffer* dest) {
514 debug_only(const CodeBuffer* src0 = src);
515 int sect = CodeBuffer::SECT_NONE;
516 // Look for olda in the source buffer, and all previous incarnations
517 // if the source buffer has been expanded.
518 for (; src != NULL; src = src->before_expand()) {
519 sect = src->section_index_of(olda);
520 if (sect != CodeBuffer::SECT_NONE) break;
521 }
522 guarantee(sect != CodeBuffer::SECT_NONE, "lost track of this address");
523 address ostart = src->code_section(sect)->start();
524 address nstart = dest->code_section(sect)->start();
525 return nstart + (olda - ostart);
526 }
527
528 void Relocation::normalize_address(address& addr, const CodeSection* dest, bool allow_other_sections) {
529 address addr0 = addr;
530 if (addr0 == NULL || dest->allocates2(addr0)) return;
531 CodeBuffer* cb = dest->outer();
532 addr = new_addr_for(addr0, cb, cb);
533 assert(allow_other_sections || dest->contains2(addr),
534 "addr must be in required section");
535 }
536
537
538 void CallRelocation::set_destination(address x) {
539 pd_set_call_destination(x);
540 }
541
542 void CallRelocation::fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest) {
543 // Usually a self-relative reference to an external routine.
544 // On some platforms, the reference is absolute (not self-relative).
545 // The enhanced use of pd_call_destination sorts this all out.
546 address orig_addr = old_addr_for(addr(), src, dest);
547 address callee = pd_call_destination(orig_addr);
548 // Reassert the callee address, this time in the new copy of the code.
549 pd_set_call_destination(callee);
550 }
551
552
553 //// pack/unpack methods
554
555 void oop_Relocation::pack_data_to(CodeSection* dest) {
556 short* p = (short*) dest->locs_end();
557 p = pack_2_ints_to(p, _oop_index, _offset);
558 dest->set_locs_end((relocInfo*) p);
559 }
560
561
562 void oop_Relocation::unpack_data() {
563 unpack_2_ints(_oop_index, _offset);
564 }
565
566 void metadata_Relocation::pack_data_to(CodeSection* dest) {
567 short* p = (short*) dest->locs_end();
568 p = pack_2_ints_to(p, _metadata_index, _offset);
569 dest->set_locs_end((relocInfo*) p);
570 }
571
572
573 void metadata_Relocation::unpack_data() {
574 unpack_2_ints(_metadata_index, _offset);
575 }
576
577
578 void virtual_call_Relocation::pack_data_to(CodeSection* dest) {
579 short* p = (short*) dest->locs_end();
580 address point = dest->locs_point();
581
582 normalize_address(_cached_value, dest);
583 jint x0 = scaled_offset_null_special(_cached_value, point);
584 p = pack_1_int_to(p, x0);
585 dest->set_locs_end((relocInfo*) p);
586 }
587
588
589 void virtual_call_Relocation::unpack_data() {
590 jint x0 = unpack_1_int();
591 address point = addr();
592 _cached_value = x0==0? NULL: address_from_scaled_offset(x0, point);
593 }
594
595
596 void static_stub_Relocation::pack_data_to(CodeSection* dest) {
597 short* p = (short*) dest->locs_end();
598 CodeSection* insts = dest->outer()->insts();
599 normalize_address(_static_call, insts);
600 p = pack_1_int_to(p, scaled_offset(_static_call, insts->start()));
601 dest->set_locs_end((relocInfo*) p);
602 }
603
604 void static_stub_Relocation::unpack_data() {
605 address base = binding()->section_start(CodeBuffer::SECT_INSTS);
606 jint offset = unpack_1_int();
607 _static_call = address_from_scaled_offset(offset, base);
608 }
609
610 void trampoline_stub_Relocation::pack_data_to(CodeSection* dest ) {
611 short* p = (short*) dest->locs_end();
612 CodeSection* insts = dest->outer()->insts();
613 normalize_address(_owner, insts);
614 p = pack_1_int_to(p, scaled_offset(_owner, insts->start()));
615 dest->set_locs_end((relocInfo*) p);
616 }
617
618 void trampoline_stub_Relocation::unpack_data() {
619 address base = binding()->section_start(CodeBuffer::SECT_INSTS);
620 _owner = address_from_scaled_offset(unpack_1_int(), base);
621 }
622
623 void external_word_Relocation::pack_data_to(CodeSection* dest) {
624 short* p = (short*) dest->locs_end();
625 int32_t index = runtime_address_to_index(_target);
626 #ifndef _LP64
627 p = pack_1_int_to(p, index);
628 #else
629 if (is_reloc_index(index)) {
630 p = pack_2_ints_to(p, index, 0);
631 } else {
632 jlong t = (jlong) _target;
633 int32_t lo = low(t);
634 int32_t hi = high(t);
635 p = pack_2_ints_to(p, lo, hi);
636 DEBUG_ONLY(jlong t1 = jlong_from(hi, lo));
637 assert(!is_reloc_index(t1) && (address) t1 == _target, "not symmetric");
638 }
639 #endif /* _LP64 */
640 dest->set_locs_end((relocInfo*) p);
641 }
642
643
644 void external_word_Relocation::unpack_data() {
645 #ifndef _LP64
646 _target = index_to_runtime_address(unpack_1_int());
647 #else
648 int32_t lo, hi;
649 unpack_2_ints(lo, hi);
650 jlong t = jlong_from(hi, lo);;
651 if (is_reloc_index(t)) {
652 _target = index_to_runtime_address(t);
653 } else {
654 _target = (address) t;
655 }
656 #endif /* _LP64 */
657 }
658
659
660 void internal_word_Relocation::pack_data_to(CodeSection* dest) {
661 short* p = (short*) dest->locs_end();
662 normalize_address(_target, dest, true);
663
664 // Check whether my target address is valid within this section.
665 // If not, strengthen the relocation type to point to another section.
666 int sindex = _section;
667 if (sindex == CodeBuffer::SECT_NONE && _target != NULL
668 && (!dest->allocates(_target) || _target == dest->locs_point())) {
669 sindex = dest->outer()->section_index_of(_target);
670 guarantee(sindex != CodeBuffer::SECT_NONE, "must belong somewhere");
671 relocInfo* base = dest->locs_end() - 1;
672 assert(base->type() == this->type(), "sanity");
673 // Change the written type, to be section_word_type instead.
674 base->set_type(relocInfo::section_word_type);
675 }
676
677 // Note: An internal_word relocation cannot refer to its own instruction,
678 // because we reserve "0" to mean that the pointer itself is embedded
679 // in the code stream. We use a section_word relocation for such cases.
680
681 if (sindex == CodeBuffer::SECT_NONE) {
682 assert(type() == relocInfo::internal_word_type, "must be base class");
683 guarantee(_target == NULL || dest->allocates2(_target), "must be within the given code section");
684 jint x0 = scaled_offset_null_special(_target, dest->locs_point());
685 assert(!(x0 == 0 && _target != NULL), "correct encoding of null target");
686 p = pack_1_int_to(p, x0);
687 } else {
688 assert(_target != NULL, "sanity");
689 CodeSection* sect = dest->outer()->code_section(sindex);
690 guarantee(sect->allocates2(_target), "must be in correct section");
691 address base = sect->start();
692 jint offset = scaled_offset(_target, base);
693 assert((uint)sindex < (uint)CodeBuffer::SECT_LIMIT, "sanity");
694 assert(CodeBuffer::SECT_LIMIT <= (1 << section_width), "section_width++");
695 p = pack_1_int_to(p, (offset << section_width) | sindex);
696 }
697
698 dest->set_locs_end((relocInfo*) p);
699 }
700
701
702 void internal_word_Relocation::unpack_data() {
703 jint x0 = unpack_1_int();
704 _target = x0==0? NULL: address_from_scaled_offset(x0, addr());
705 _section = CodeBuffer::SECT_NONE;
706 }
707
708
709 void section_word_Relocation::unpack_data() {
710 jint x = unpack_1_int();
711 jint offset = (x >> section_width);
712 int sindex = (x & ((1<<section_width)-1));
713 address base = binding()->section_start(sindex);
714
715 _section = sindex;
716 _target = address_from_scaled_offset(offset, base);
717 }
718
719 //// miscellaneous methods
720 oop* oop_Relocation::oop_addr() {
721 int n = _oop_index;
722 if (n == 0) {
723 // oop is stored in the code stream
724 return (oop*) pd_address_in_code();
725 } else {
726 // oop is stored in table at nmethod::oops_begin
727 return code()->oop_addr_at(n);
728 }
729 }
730
731
732 oop oop_Relocation::oop_value() {
733 oop v = *oop_addr();
734 // clean inline caches store a special pseudo-null
735 if (v == (oop)Universe::non_oop_word()) v = NULL;
736 return v;
737 }
738
739
740 void oop_Relocation::fix_oop_relocation() {
741 if (!oop_is_immediate()) {
742 // get the oop from the pool, and re-insert it into the instruction:
743 set_value(value());
744 }
745 }
746
747
748 void oop_Relocation::verify_oop_relocation() {
749 if (!oop_is_immediate()) {
750 // get the oop from the pool, and re-insert it into the instruction:
751 verify_value(value());
752 }
753 }
754
755 // meta data versions
756 Metadata** metadata_Relocation::metadata_addr() {
757 int n = _metadata_index;
758 if (n == 0) {
759 // metadata is stored in the code stream
760 return (Metadata**) pd_address_in_code();
761 } else {
762 // metadata is stored in table at nmethod::metadatas_begin
763 return code()->metadata_addr_at(n);
764 }
765 }
766
767
768 Metadata* metadata_Relocation::metadata_value() {
769 Metadata* v = *metadata_addr();
770 // clean inline caches store a special pseudo-null
771 if (v == (Metadata*)Universe::non_oop_word()) v = NULL;
772 return v;
773 }
774
775
776 void metadata_Relocation::fix_metadata_relocation() {
777 if (!metadata_is_immediate()) {
778 // get the metadata from the pool, and re-insert it into the instruction:
779 pd_fix_value(value());
780 }
781 }
782
783
784 void metadata_Relocation::verify_metadata_relocation() {
785 if (!metadata_is_immediate()) {
786 // get the metadata from the pool, and re-insert it into the instruction:
787 verify_value(value());
788 }
789 }
790
791 address virtual_call_Relocation::cached_value() {
792 assert(_cached_value != NULL && _cached_value < addr(), "must precede ic_call");
793 return _cached_value;
794 }
795
796
797 void virtual_call_Relocation::clear_inline_cache() {
798 // No stubs for ICs
799 // Clean IC
800 ResourceMark rm;
801 CompiledIC* icache = CompiledIC_at(this);
802 icache->set_to_clean();
803 }
804
805
806 void opt_virtual_call_Relocation::clear_inline_cache() {
807 // No stubs for ICs
808 // Clean IC
809 ResourceMark rm;
810 CompiledIC* icache = CompiledIC_at(this);
811 icache->set_to_clean();
812 }
813
814
815 address opt_virtual_call_Relocation::static_stub() {
816 // search for the static stub who points back to this static call
817 address static_call_addr = addr();
818 RelocIterator iter(code());
819 while (iter.next()) {
820 if (iter.type() == relocInfo::static_stub_type) {
821 static_stub_Relocation* stub_reloc = iter.static_stub_reloc();
822 if (stub_reloc->static_call() == static_call_addr) {
823 return iter.addr();
824 }
825 }
826 }
827 return NULL;
828 }
829
830
831 void static_call_Relocation::clear_inline_cache() {
832 // Safe call site info
833 CompiledStaticCall* handler = compiledStaticCall_at(this);
834 handler->set_to_clean();
835 }
836
837
838 address static_call_Relocation::static_stub() {
839 // search for the static stub who points back to this static call
840 address static_call_addr = addr();
841 RelocIterator iter(code());
842 while (iter.next()) {
843 if (iter.type() == relocInfo::static_stub_type) {
844 static_stub_Relocation* stub_reloc = iter.static_stub_reloc();
845 if (stub_reloc->static_call() == static_call_addr) {
846 return iter.addr();
847 }
848 }
849 }
850 return NULL;
851 }
852
853 // Finds the trampoline address for a call. If no trampoline stub is
854 // found NULL is returned which can be handled by the caller.
855 address trampoline_stub_Relocation::get_trampoline_for(address call, nmethod* code) {
856 // There are no relocations available when the code gets relocated
857 // because of CodeBuffer expansion.
858 if (code->relocation_size() == 0)
859 return NULL;
860
861 RelocIterator iter(code, call);
862 while (iter.next()) {
863 if (iter.type() == relocInfo::trampoline_stub_type) {
864 if (iter.trampoline_stub_reloc()->owner() == call) {
865 return iter.addr();
866 }
867 }
868 }
869
870 return NULL;
871 }
872
873 void static_stub_Relocation::clear_inline_cache() {
874 // Call stub is only used when calling the interpreted code.
875 // It does not really need to be cleared, except that we want to clean out the methodoop.
876 CompiledStaticCall::set_stub_to_clean(this);
877 }
878
879
880 void external_word_Relocation::fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest) {
881 address target = _target;
882 if (target == NULL) {
883 // An absolute embedded reference to an external location,
884 // which means there is nothing to fix here.
885 return;
886 }
887 // Probably this reference is absolute, not relative, so the
888 // following is probably a no-op.
889 assert(src->section_index_of(target) == CodeBuffer::SECT_NONE, "sanity");
890 set_value(target);
891 }
892
893
894 address external_word_Relocation::target() {
895 address target = _target;
896 if (target == NULL) {
897 target = pd_get_address_from_code();
898 }
899 return target;
900 }
901
902
903 void internal_word_Relocation::fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest) {
904 address target = _target;
905 if (target == NULL) {
906 target = new_addr_for(this->target(), src, dest);
907 }
908 set_value(target);
909 }
910
911
912 address internal_word_Relocation::target() {
913 address target = _target;
914 if (target == NULL) {
915 if (addr_in_const()) {
916 target = *(address*)addr();
917 } else {
918 target = pd_get_address_from_code();
919 }
920 }
921 return target;
922 }
923
924 //---------------------------------------------------------------------------------
925 // Non-product code
926
927 #ifndef PRODUCT
928
929 static const char* reloc_type_string(relocInfo::relocType t) {
930 switch (t) {
931 #define EACH_CASE(name) \
932 case relocInfo::name##_type: \
933 return #name;
934
935 APPLY_TO_RELOCATIONS(EACH_CASE);
936 #undef EACH_CASE
937
938 case relocInfo::none:
939 return "none";
940 case relocInfo::data_prefix_tag:
941 return "prefix";
942 default:
943 return "UNKNOWN RELOC TYPE";
944 }
945 }
946
947
948 void RelocIterator::print_current() {
949 if (!has_current()) {
950 tty->print_cr("(no relocs)");
951 return;
952 }
953 tty->print("relocInfo@" INTPTR_FORMAT " [type=%d(%s) addr=" INTPTR_FORMAT " offset=%d",
954 p2i(_current), type(), reloc_type_string((relocInfo::relocType) type()), p2i(_addr), _current->addr_offset());
955 if (current()->format() != 0)
956 tty->print(" format=%d", current()->format());
957 if (datalen() == 1) {
958 tty->print(" data=%d", data()[0]);
959 } else if (datalen() > 0) {
960 tty->print(" data={");
961 for (int i = 0; i < datalen(); i++) {
962 tty->print("%04x", data()[i] & 0xFFFF);
963 }
964 tty->print("}");
965 }
966 tty->print("]");
967 switch (type()) {
968 case relocInfo::oop_type:
969 {
970 oop_Relocation* r = oop_reloc();
971 oop* oop_addr = NULL;
972 oop raw_oop = NULL;
973 oop oop_value = NULL;
974 if (code() != NULL || r->oop_is_immediate()) {
975 oop_addr = r->oop_addr();
976 raw_oop = *oop_addr;
977 oop_value = r->oop_value();
978 }
979 tty->print(" | [oop_addr=" INTPTR_FORMAT " *=" INTPTR_FORMAT " offset=%d]",
980 p2i(oop_addr), p2i(raw_oop), r->offset());
981 // Do not print the oop by default--we want this routine to
982 // work even during GC or other inconvenient times.
983 if (WizardMode && oop_value != NULL) {
984 tty->print("oop_value=" INTPTR_FORMAT ": ", p2i(oop_value));
985 oop_value->print_value_on(tty);
986 }
987 break;
988 }
989 case relocInfo::metadata_type:
990 {
991 metadata_Relocation* r = metadata_reloc();
992 Metadata** metadata_addr = NULL;
993 Metadata* raw_metadata = NULL;
994 Metadata* metadata_value = NULL;
995 if (code() != NULL || r->metadata_is_immediate()) {
996 metadata_addr = r->metadata_addr();
997 raw_metadata = *metadata_addr;
998 metadata_value = r->metadata_value();
999 }
1000 tty->print(" | [metadata_addr=" INTPTR_FORMAT " *=" INTPTR_FORMAT " offset=%d]",
1001 p2i(metadata_addr), p2i(raw_metadata), r->offset());
1002 if (metadata_value != NULL) {
1003 tty->print("metadata_value=" INTPTR_FORMAT ": ", p2i(metadata_value));
1004 metadata_value->print_value_on(tty);
1005 }
1006 break;
1007 }
1008 case relocInfo::external_word_type:
1009 case relocInfo::internal_word_type:
1010 case relocInfo::section_word_type:
1011 {
1012 DataRelocation* r = (DataRelocation*) reloc();
1013 tty->print(" | [target=" INTPTR_FORMAT "]", p2i(r->value())); //value==target
1014 break;
1015 }
1016 case relocInfo::static_call_type:
1017 case relocInfo::runtime_call_type:
1018 {
1019 CallRelocation* r = (CallRelocation*) reloc();
1020 tty->print(" | [destination=" INTPTR_FORMAT "]", p2i(r->destination()));
1021 break;
1022 }
1023 case relocInfo::virtual_call_type:
1024 {
1025 virtual_call_Relocation* r = (virtual_call_Relocation*) reloc();
1026 tty->print(" | [destination=" INTPTR_FORMAT " cached_value=" INTPTR_FORMAT "]",
1027 p2i(r->destination()), p2i(r->cached_value()));
1028 break;
1029 }
1030 case relocInfo::static_stub_type:
1031 {
1032 static_stub_Relocation* r = (static_stub_Relocation*) reloc();
1033 tty->print(" | [static_call=" INTPTR_FORMAT "]", p2i(r->static_call()));
1034 break;
1035 }
1036 case relocInfo::trampoline_stub_type:
1037 {
1038 trampoline_stub_Relocation* r = (trampoline_stub_Relocation*) reloc();
1039 tty->print(" | [trampoline owner=" INTPTR_FORMAT "]", p2i(r->owner()));
1040 break;
1041 }
1042 }
1043 tty->cr();
1044 }
1045
1046
1047 void RelocIterator::print() {
1048 RelocIterator save_this = (*this);
1049 relocInfo* scan = _current;
1050 if (!has_current()) scan += 1; // nothing to scan here!
1051
1052 bool skip_next = has_current();
1053 bool got_next;
1054 while (true) {
1055 got_next = (skip_next || next());
1056 skip_next = false;
1057
1058 tty->print(" @" INTPTR_FORMAT ": ", p2i(scan));
1059 relocInfo* newscan = _current+1;
1060 if (!has_current()) newscan -= 1; // nothing to scan here!
1061 while (scan < newscan) {
1062 tty->print("%04x", *(short*)scan & 0xFFFF);
1063 scan++;
1064 }
1065 tty->cr();
1066
1067 if (!got_next) break;
1068 print_current();
1069 }
1070
1071 (*this) = save_this;
1072 }
1073
1074 // For the debugger:
1075 extern "C"
1076 void print_blob_locs(nmethod* nm) {
1077 nm->print();
1078 RelocIterator iter(nm);
1079 iter.print();
1080 }
1081 extern "C"
1082 void print_buf_locs(CodeBuffer* cb) {
1083 FlagSetting fs(PrintRelocations, true);
1084 cb->print();
1085 }
1086 #endif // !PRODUCT