1 /*
2 * Copyright (c) 1997, 2010, 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 "incls/_precompiled.incl"
26 # include "incls/_relocInfo.cpp.incl"
27
28
29 const RelocationHolder RelocationHolder::none; // its type is relocInfo::none
30
31
32 // Implementation of relocInfo
33
34 #ifdef ASSERT
35 relocInfo::relocInfo(relocType t, int off, int f) {
36 assert(t != data_prefix_tag, "cannot build a prefix this way");
37 assert((t & type_mask) == t, "wrong type");
38 assert((f & format_mask) == f, "wrong format");
39 assert(off >= 0 && off < offset_limit(), "offset out off bounds");
40 assert((off & (offset_unit-1)) == 0, "misaligned offset");
41 (*this) = relocInfo(t, RAW_BITS, off, f);
42 }
43 #endif
44
45 void relocInfo::initialize(CodeSection* dest, Relocation* reloc) {
46 relocInfo* data = this+1; // here's where the data might go
47 dest->set_locs_end(data); // sync end: the next call may read dest.locs_end
48 reloc->pack_data_to(dest); // maybe write data into locs, advancing locs_end
49 relocInfo* data_limit = dest->locs_end();
50 if (data_limit > data) {
51 relocInfo suffix = (*this);
52 data_limit = this->finish_prefix((short*) data_limit);
53 // Finish up with the suffix. (Hack note: pack_data_to might edit this.)
54 *data_limit = suffix;
55 dest->set_locs_end(data_limit+1);
56 }
57 }
58
59 relocInfo* relocInfo::finish_prefix(short* prefix_limit) {
60 assert(sizeof(relocInfo) == sizeof(short), "change this code");
61 short* p = (short*)(this+1);
62 assert(prefix_limit >= p, "must be a valid span of data");
63 int plen = prefix_limit - p;
64 if (plen == 0) {
65 debug_only(_value = 0xFFFF);
66 return this; // no data: remove self completely
67 }
68 if (plen == 1 && fits_into_immediate(p[0])) {
69 (*this) = immediate_relocInfo(p[0]); // move data inside self
70 return this+1;
71 }
72 // cannot compact, so just update the count and return the limit pointer
73 (*this) = prefix_relocInfo(plen); // write new datalen
74 assert(data() + datalen() == prefix_limit, "pointers must line up");
75 return (relocInfo*)prefix_limit;
76 }
77
78
79 void relocInfo::set_type(relocType t) {
80 int old_offset = addr_offset();
81 int old_format = format();
82 (*this) = relocInfo(t, old_offset, old_format);
83 assert(type()==(int)t, "sanity check");
84 assert(addr_offset()==old_offset, "sanity check");
85 assert(format()==old_format, "sanity check");
86 }
87
88
89 void relocInfo::set_format(int f) {
90 int old_offset = addr_offset();
91 assert((f & format_mask) == f, "wrong format");
92 _value = (_value & ~(format_mask << offset_width)) | (f << offset_width);
93 assert(addr_offset()==old_offset, "sanity check");
94 }
95
96
97 void relocInfo::change_reloc_info_for_address(RelocIterator *itr, address pc, relocType old_type, relocType new_type) {
98 bool found = false;
99 while (itr->next() && !found) {
100 if (itr->addr() == pc) {
101 assert(itr->type()==old_type, "wrong relocInfo type found");
102 itr->current()->set_type(new_type);
103 found=true;
104 }
105 }
106 assert(found, "no relocInfo found for pc");
107 }
108
109
110 void relocInfo::remove_reloc_info_for_address(RelocIterator *itr, address pc, relocType old_type) {
111 change_reloc_info_for_address(itr, pc, old_type, none);
112 }
113
114
115 // ----------------------------------------------------------------------------------------------------
116 // Implementation of RelocIterator
117
118 void RelocIterator::initialize(nmethod* nm, address begin, address limit) {
119 initialize_misc();
120
121 if (nm == NULL && begin != NULL) {
122 // allow nmethod to be deduced from beginning address
123 CodeBlob* cb = CodeCache::find_blob(begin);
124 nm = cb->as_nmethod_or_null();
125 }
126 assert(nm != NULL, "must be able to deduce nmethod from other arguments");
127
128 _code = nm;
129 _current = nm->relocation_begin() - 1;
130 _end = nm->relocation_end();
131 _addr = nm->content_begin();
132
133 // Initialize code sections.
134 _section_start[CodeBuffer::SECT_CONSTS] = nm->consts_begin();
135 _section_start[CodeBuffer::SECT_INSTS ] = nm->insts_begin() ;
136 _section_start[CodeBuffer::SECT_STUBS ] = nm->stub_begin() ;
137
138 _section_end [CodeBuffer::SECT_CONSTS] = nm->consts_end() ;
139 _section_end [CodeBuffer::SECT_INSTS ] = nm->insts_end() ;
140 _section_end [CodeBuffer::SECT_STUBS ] = nm->stub_end() ;
141
142 assert(!has_current(), "just checking");
143 assert(begin == NULL || begin >= nm->code_begin(), "in bounds");
144 assert(limit == NULL || limit <= nm->code_end(), "in bounds");
145 set_limits(begin, limit);
146 }
147
148
149 RelocIterator::RelocIterator(CodeSection* cs, address begin, address limit) {
150 initialize_misc();
151
152 _current = cs->locs_start()-1;
153 _end = cs->locs_end();
154 _addr = cs->start();
155 _code = NULL; // Not cb->blob();
156
157 CodeBuffer* cb = cs->outer();
158 assert((int) SECT_LIMIT == CodeBuffer::SECT_LIMIT, "my copy must be equal");
159 for (int n = (int) CodeBuffer::SECT_FIRST; n < (int) CodeBuffer::SECT_LIMIT; n++) {
160 CodeSection* cs = cb->code_section(n);
161 _section_start[n] = cs->start();
162 _section_end [n] = cs->end();
163 }
164
165 assert(!has_current(), "just checking");
166
167 assert(begin == NULL || begin >= cs->start(), "in bounds");
168 assert(limit == NULL || limit <= cs->end(), "in bounds");
169 set_limits(begin, limit);
170 }
171
172
173 enum { indexCardSize = 128 };
174 struct RelocIndexEntry {
175 jint addr_offset; // offset from header_end of an addr()
176 jint reloc_offset; // offset from header_end of a relocInfo (prefix)
177 };
178
179
180 bool RelocIterator::addr_in_const() const {
181 const int n = CodeBuffer::SECT_CONSTS;
182 return section_start(n) <= addr() && addr() < section_end(n);
183 }
184
185
186 static inline int num_cards(int code_size) {
187 return (code_size-1) / indexCardSize;
188 }
189
190
191 int RelocIterator::locs_and_index_size(int code_size, int locs_size) {
192 if (!UseRelocIndex) return locs_size; // no index
193 code_size = round_to(code_size, oopSize);
194 locs_size = round_to(locs_size, oopSize);
195 int index_size = num_cards(code_size) * sizeof(RelocIndexEntry);
196 // format of indexed relocs:
197 // relocation_begin: relocInfo ...
198 // index: (addr,reloc#) ...
199 // indexSize :relocation_end
200 return locs_size + index_size + BytesPerInt;
201 }
202
203
204 void RelocIterator::create_index(relocInfo* dest_begin, int dest_count, relocInfo* dest_end) {
205 address relocation_begin = (address)dest_begin;
206 address relocation_end = (address)dest_end;
207 int total_size = relocation_end - relocation_begin;
208 int locs_size = dest_count * sizeof(relocInfo);
209 if (!UseRelocIndex) {
210 Copy::fill_to_bytes(relocation_begin + locs_size, total_size-locs_size, 0);
211 return;
212 }
213 int index_size = total_size - locs_size - BytesPerInt; // find out how much space is left
214 int ncards = index_size / sizeof(RelocIndexEntry);
215 assert(total_size == locs_size + index_size + BytesPerInt, "checkin'");
216 assert(index_size >= 0 && index_size % sizeof(RelocIndexEntry) == 0, "checkin'");
217 jint* index_size_addr = (jint*)relocation_end - 1;
218
219 assert(sizeof(jint) == BytesPerInt, "change this code");
220
221 *index_size_addr = index_size;
222 if (index_size != 0) {
223 assert(index_size > 0, "checkin'");
224
225 RelocIndexEntry* index = (RelocIndexEntry *)(relocation_begin + locs_size);
226 assert(index == (RelocIndexEntry*)index_size_addr - ncards, "checkin'");
227
228 // walk over the relocations, and fill in index entries as we go
229 RelocIterator iter;
230 const address initial_addr = NULL;
231 relocInfo* const initial_current = dest_begin - 1; // biased by -1 like elsewhere
232
233 iter._code = NULL;
234 iter._addr = initial_addr;
235 iter._limit = (address)(intptr_t)(ncards * indexCardSize);
236 iter._current = initial_current;
237 iter._end = dest_begin + dest_count;
238
239 int i = 0;
240 address next_card_addr = (address)indexCardSize;
241 int addr_offset = 0;
242 int reloc_offset = 0;
243 while (true) {
244 // Checkpoint the iterator before advancing it.
245 addr_offset = iter._addr - initial_addr;
246 reloc_offset = iter._current - initial_current;
247 if (!iter.next()) break;
248 while (iter.addr() >= next_card_addr) {
249 index[i].addr_offset = addr_offset;
250 index[i].reloc_offset = reloc_offset;
251 i++;
252 next_card_addr += indexCardSize;
253 }
254 }
255 while (i < ncards) {
256 index[i].addr_offset = addr_offset;
257 index[i].reloc_offset = reloc_offset;
258 i++;
259 }
260 }
261 }
262
263
264 void RelocIterator::set_limits(address begin, address limit) {
265 int index_size = 0;
266 if (UseRelocIndex && _code != NULL) {
267 index_size = ((jint*)_end)[-1];
268 _end = (relocInfo*)( (address)_end - index_size - BytesPerInt );
269 }
270
271 _limit = limit;
272
273 // the limit affects this next stuff:
274 if (begin != NULL) {
275 #ifdef ASSERT
276 // In ASSERT mode we do not actually use the index, but simply
277 // check that its contents would have led us to the right answer.
278 address addrCheck = _addr;
279 relocInfo* infoCheck = _current;
280 #endif // ASSERT
281 if (index_size > 0) {
282 // skip ahead
283 RelocIndexEntry* index = (RelocIndexEntry*)_end;
284 RelocIndexEntry* index_limit = (RelocIndexEntry*)((address)index + index_size);
285 assert(_addr == _code->code_begin(), "_addr must be unadjusted");
286 int card = (begin - _addr) / indexCardSize;
287 if (card > 0) {
288 if (index+card-1 < index_limit) index += card-1;
289 else index = index_limit - 1;
290 #ifdef ASSERT
291 addrCheck = _addr + index->addr_offset;
292 infoCheck = _current + index->reloc_offset;
293 #else
294 // Advance the iterator immediately to the last valid state
295 // for the previous card. Calling "next" will then advance
296 // it to the first item on the required card.
297 _addr += index->addr_offset;
298 _current += index->reloc_offset;
299 #endif // ASSERT
300 }
301 }
302
303 relocInfo* backup;
304 address backup_addr;
305 while (true) {
306 backup = _current;
307 backup_addr = _addr;
308 #ifdef ASSERT
309 if (backup == infoCheck) {
310 assert(backup_addr == addrCheck, "must match"); addrCheck = NULL; infoCheck = NULL;
311 } else {
312 assert(addrCheck == NULL || backup_addr <= addrCheck, "must not pass addrCheck");
313 }
314 #endif // ASSERT
315 if (!next() || addr() >= begin) break;
316 }
317 assert(addrCheck == NULL || addrCheck == backup_addr, "must have matched addrCheck");
318 assert(infoCheck == NULL || infoCheck == backup, "must have matched infoCheck");
319 // At this point, either we are at the first matching record,
320 // or else there is no such record, and !has_current().
321 // In either case, revert to the immediatly preceding state.
322 _current = backup;
323 _addr = backup_addr;
324 set_has_current(false);
325 }
326 }
327
328
329 void RelocIterator::set_limit(address limit) {
330 address code_end = (address)code() + code()->size();
331 assert(limit == NULL || limit <= code_end, "in bounds");
332 _limit = limit;
333 }
334
335
336 void PatchingRelocIterator:: prepass() {
337 // turn breakpoints off during patching
338 _init_state = (*this); // save cursor
339 while (next()) {
340 if (type() == relocInfo::breakpoint_type) {
341 breakpoint_reloc()->set_active(false);
342 }
343 }
344 (RelocIterator&)(*this) = _init_state; // reset cursor for client
345 }
346
347
348 void PatchingRelocIterator:: postpass() {
349 // turn breakpoints back on after patching
350 (RelocIterator&)(*this) = _init_state; // reset cursor again
351 while (next()) {
352 if (type() == relocInfo::breakpoint_type) {
353 breakpoint_Relocation* bpt = breakpoint_reloc();
354 bpt->set_active(bpt->enabled());
355 }
356 }
357 }
358
359
360 // All the strange bit-encodings are in here.
361 // The idea is to encode relocation data which are small integers
362 // very efficiently (a single extra halfword). Larger chunks of
363 // relocation data need a halfword header to hold their size.
364 void RelocIterator::advance_over_prefix() {
365 if (_current->is_datalen()) {
366 _data = (short*) _current->data();
367 _datalen = _current->datalen();
368 _current += _datalen + 1; // skip the embedded data & header
369 } else {
370 _databuf = _current->immediate();
371 _data = &_databuf;
372 _datalen = 1;
373 _current++; // skip the header
374 }
375 // The client will see the following relocInfo, whatever that is.
376 // It is the reloc to which the preceding data applies.
377 }
378
379
380 void RelocIterator::initialize_misc() {
381 set_has_current(false);
382 for (int i = (int) CodeBuffer::SECT_FIRST; i < (int) CodeBuffer::SECT_LIMIT; i++) {
383 _section_start[i] = NULL; // these will be lazily computed, if needed
384 _section_end [i] = NULL;
385 }
386 }
387
388
389 Relocation* RelocIterator::reloc() {
390 // (take the "switch" out-of-line)
391 relocInfo::relocType t = type();
392 if (false) {}
393 #define EACH_TYPE(name) \
394 else if (t == relocInfo::name##_type) { \
395 return name##_reloc(); \
396 }
397 APPLY_TO_RELOCATIONS(EACH_TYPE);
398 #undef EACH_TYPE
399 assert(t == relocInfo::none, "must be padding");
400 return new(_rh) Relocation();
401 }
402
403
404 //////// Methods for flyweight Relocation types
405
406
407 RelocationHolder RelocationHolder::plus(int offset) const {
408 if (offset != 0) {
409 switch (type()) {
410 case relocInfo::none:
411 break;
412 case relocInfo::oop_type:
413 {
414 oop_Relocation* r = (oop_Relocation*)reloc();
415 return oop_Relocation::spec(r->oop_index(), r->offset() + offset);
416 }
417 default:
418 ShouldNotReachHere();
419 }
420 }
421 return (*this);
422 }
423
424
425 void Relocation::guarantee_size() {
426 guarantee(false, "Make _relocbuf bigger!");
427 }
428
429 // some relocations can compute their own values
430 address Relocation::value() {
431 ShouldNotReachHere();
432 return NULL;
433 }
434
435
436 void Relocation::set_value(address x) {
437 ShouldNotReachHere();
438 }
439
440
441 RelocationHolder Relocation::spec_simple(relocInfo::relocType rtype) {
442 if (rtype == relocInfo::none) return RelocationHolder::none;
443 relocInfo ri = relocInfo(rtype, 0);
444 RelocIterator itr;
445 itr.set_current(ri);
446 itr.reloc();
447 return itr._rh;
448 }
449
450
451 static inline bool is_index(intptr_t index) {
452 return 0 < index && index < os::vm_page_size();
453 }
454
455
456 int32_t Relocation::runtime_address_to_index(address runtime_address) {
457 assert(!is_index((intptr_t)runtime_address), "must not look like an index");
458
459 if (runtime_address == NULL) return 0;
460
461 StubCodeDesc* p = StubCodeDesc::desc_for(runtime_address);
462 if (p != NULL && p->begin() == runtime_address) {
463 assert(is_index(p->index()), "there must not be too many stubs");
464 return (int32_t)p->index();
465 } else {
466 // Known "miscellaneous" non-stub pointers:
467 // os::get_polling_page(), SafepointSynchronize::address_of_state()
468 if (PrintRelocations) {
469 tty->print_cr("random unregistered address in relocInfo: " INTPTR_FORMAT, runtime_address);
470 }
471 #ifndef _LP64
472 return (int32_t) (intptr_t)runtime_address;
473 #else
474 // didn't fit return non-index
475 return -1;
476 #endif /* _LP64 */
477 }
478 }
479
480
481 address Relocation::index_to_runtime_address(int32_t index) {
482 if (index == 0) return NULL;
483
484 if (is_index(index)) {
485 StubCodeDesc* p = StubCodeDesc::desc_for_index(index);
486 assert(p != NULL, "there must be a stub for this index");
487 return p->begin();
488 } else {
489 #ifndef _LP64
490 // this only works on 32bit machines
491 return (address) ((intptr_t) index);
492 #else
493 fatal("Relocation::index_to_runtime_address, int32_t not pointer sized");
494 return NULL;
495 #endif /* _LP64 */
496 }
497 }
498
499 address Relocation::old_addr_for(address newa,
500 const CodeBuffer* src, CodeBuffer* dest) {
501 int sect = dest->section_index_of(newa);
502 guarantee(sect != CodeBuffer::SECT_NONE, "lost track of this address");
503 address ostart = src->code_section(sect)->start();
504 address nstart = dest->code_section(sect)->start();
505 return ostart + (newa - nstart);
506 }
507
508 address Relocation::new_addr_for(address olda,
509 const CodeBuffer* src, CodeBuffer* dest) {
510 debug_only(const CodeBuffer* src0 = src);
511 int sect = CodeBuffer::SECT_NONE;
512 // Look for olda in the source buffer, and all previous incarnations
513 // if the source buffer has been expanded.
514 for (; src != NULL; src = src->before_expand()) {
515 sect = src->section_index_of(olda);
516 if (sect != CodeBuffer::SECT_NONE) break;
517 }
518 guarantee(sect != CodeBuffer::SECT_NONE, "lost track of this address");
519 address ostart = src->code_section(sect)->start();
520 address nstart = dest->code_section(sect)->start();
521 return nstart + (olda - ostart);
522 }
523
524 void Relocation::normalize_address(address& addr, const CodeSection* dest, bool allow_other_sections) {
525 address addr0 = addr;
526 if (addr0 == NULL || dest->allocates2(addr0)) return;
527 CodeBuffer* cb = dest->outer();
528 addr = new_addr_for(addr0, cb, cb);
529 assert(allow_other_sections || dest->contains2(addr),
530 "addr must be in required section");
531 }
532
533
534 void CallRelocation::set_destination(address x) {
535 pd_set_call_destination(x);
536 }
537
538 void CallRelocation::fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest) {
539 // Usually a self-relative reference to an external routine.
540 // On some platforms, the reference is absolute (not self-relative).
541 // The enhanced use of pd_call_destination sorts this all out.
542 address orig_addr = old_addr_for(addr(), src, dest);
543 address callee = pd_call_destination(orig_addr);
544 // Reassert the callee address, this time in the new copy of the code.
545 pd_set_call_destination(callee);
546 }
547
548
549 //// pack/unpack methods
550
551 void oop_Relocation::pack_data_to(CodeSection* dest) {
552 short* p = (short*) dest->locs_end();
553 p = pack_2_ints_to(p, _oop_index, _offset);
554 dest->set_locs_end((relocInfo*) p);
555 }
556
557
558 void oop_Relocation::unpack_data() {
559 unpack_2_ints(_oop_index, _offset);
560 }
561
562
563 void virtual_call_Relocation::pack_data_to(CodeSection* dest) {
564 short* p = (short*) dest->locs_end();
565 address point = dest->locs_point();
566
567 // Try to make a pointer NULL first.
568 if (_oop_limit >= point &&
569 _oop_limit <= point + NativeCall::instruction_size) {
570 _oop_limit = NULL;
571 }
572 // If the _oop_limit is NULL, it "defaults" to the end of the call.
573 // See ic_call_Relocation::oop_limit() below.
574
575 normalize_address(_first_oop, dest);
576 normalize_address(_oop_limit, dest);
577 jint x0 = scaled_offset_null_special(_first_oop, point);
578 jint x1 = scaled_offset_null_special(_oop_limit, point);
579 p = pack_2_ints_to(p, x0, x1);
580 dest->set_locs_end((relocInfo*) p);
581 }
582
583
584 void virtual_call_Relocation::unpack_data() {
585 jint x0, x1; unpack_2_ints(x0, x1);
586 address point = addr();
587 _first_oop = x0==0? NULL: address_from_scaled_offset(x0, point);
588 _oop_limit = x1==0? NULL: address_from_scaled_offset(x1, point);
589 }
590
591
592 void static_stub_Relocation::pack_data_to(CodeSection* dest) {
593 short* p = (short*) dest->locs_end();
594 CodeSection* insts = dest->outer()->insts();
595 normalize_address(_static_call, insts);
596 p = pack_1_int_to(p, scaled_offset(_static_call, insts->start()));
597 dest->set_locs_end((relocInfo*) p);
598 }
599
600 void static_stub_Relocation::unpack_data() {
601 address base = binding()->section_start(CodeBuffer::SECT_INSTS);
602 _static_call = address_from_scaled_offset(unpack_1_int(), base);
603 }
604
605
606 void external_word_Relocation::pack_data_to(CodeSection* dest) {
607 short* p = (short*) dest->locs_end();
608 int32_t index = runtime_address_to_index(_target);
609 #ifndef _LP64
610 p = pack_1_int_to(p, index);
611 #else
612 if (is_index(index)) {
613 p = pack_2_ints_to(p, index, 0);
614 } else {
615 jlong t = (jlong) _target;
616 int32_t lo = low(t);
617 int32_t hi = high(t);
618 p = pack_2_ints_to(p, lo, hi);
619 DEBUG_ONLY(jlong t1 = jlong_from(hi, lo));
620 assert(!is_index(t1) && (address) t1 == _target, "not symmetric");
621 }
622 #endif /* _LP64 */
623 dest->set_locs_end((relocInfo*) p);
624 }
625
626
627 void external_word_Relocation::unpack_data() {
628 #ifndef _LP64
629 _target = index_to_runtime_address(unpack_1_int());
630 #else
631 int32_t lo, hi;
632 unpack_2_ints(lo, hi);
633 jlong t = jlong_from(hi, lo);;
634 if (is_index(t)) {
635 _target = index_to_runtime_address(t);
636 } else {
637 _target = (address) t;
638 }
639 #endif /* _LP64 */
640 }
641
642
643 void internal_word_Relocation::pack_data_to(CodeSection* dest) {
644 short* p = (short*) dest->locs_end();
645 normalize_address(_target, dest, true);
646
647 // Check whether my target address is valid within this section.
648 // If not, strengthen the relocation type to point to another section.
649 int sindex = _section;
650 if (sindex == CodeBuffer::SECT_NONE && _target != NULL
651 && (!dest->allocates(_target) || _target == dest->locs_point())) {
652 sindex = dest->outer()->section_index_of(_target);
653 guarantee(sindex != CodeBuffer::SECT_NONE, "must belong somewhere");
654 relocInfo* base = dest->locs_end() - 1;
655 assert(base->type() == this->type(), "sanity");
656 // Change the written type, to be section_word_type instead.
657 base->set_type(relocInfo::section_word_type);
658 }
659
660 // Note: An internal_word relocation cannot refer to its own instruction,
661 // because we reserve "0" to mean that the pointer itself is embedded
662 // in the code stream. We use a section_word relocation for such cases.
663
664 if (sindex == CodeBuffer::SECT_NONE) {
665 assert(type() == relocInfo::internal_word_type, "must be base class");
666 guarantee(_target == NULL || dest->allocates2(_target), "must be within the given code section");
667 jint x0 = scaled_offset_null_special(_target, dest->locs_point());
668 assert(!(x0 == 0 && _target != NULL), "correct encoding of null target");
669 p = pack_1_int_to(p, x0);
670 } else {
671 assert(_target != NULL, "sanity");
672 CodeSection* sect = dest->outer()->code_section(sindex);
673 guarantee(sect->allocates2(_target), "must be in correct section");
674 address base = sect->start();
675 jint offset = scaled_offset(_target, base);
676 assert((uint)sindex < (uint)CodeBuffer::SECT_LIMIT, "sanity");
677 assert(CodeBuffer::SECT_LIMIT <= (1 << section_width), "section_width++");
678 p = pack_1_int_to(p, (offset << section_width) | sindex);
679 }
680
681 dest->set_locs_end((relocInfo*) p);
682 }
683
684
685 void internal_word_Relocation::unpack_data() {
686 jint x0 = unpack_1_int();
687 _target = x0==0? NULL: address_from_scaled_offset(x0, addr());
688 _section = CodeBuffer::SECT_NONE;
689 }
690
691
692 void section_word_Relocation::unpack_data() {
693 jint x = unpack_1_int();
694 jint offset = (x >> section_width);
695 int sindex = (x & ((1<<section_width)-1));
696 address base = binding()->section_start(sindex);
697
698 _section = sindex;
699 _target = address_from_scaled_offset(offset, base);
700 }
701
702
703 void breakpoint_Relocation::pack_data_to(CodeSection* dest) {
704 short* p = (short*) dest->locs_end();
705 address point = dest->locs_point();
706
707 *p++ = _bits;
708
709 assert(_target != NULL, "sanity");
710
711 if (internal()) normalize_address(_target, dest);
712
713 jint target_bits =
714 (jint)( internal() ? scaled_offset (_target, point)
715 : runtime_address_to_index(_target) );
716 if (settable()) {
717 // save space for set_target later
718 p = add_jint(p, target_bits);
719 } else {
720 p = add_var_int(p, target_bits);
721 }
722
723 for (int i = 0; i < instrlen(); i++) {
724 // put placeholder words until bytes can be saved
725 p = add_short(p, (short)0x7777);
726 }
727
728 dest->set_locs_end((relocInfo*) p);
729 }
730
731
732 void breakpoint_Relocation::unpack_data() {
733 _bits = live_bits();
734
735 int targetlen = datalen() - 1 - instrlen();
736 jint target_bits = 0;
737 if (targetlen == 0) target_bits = 0;
738 else if (targetlen == 1) target_bits = *(data()+1);
739 else if (targetlen == 2) target_bits = relocInfo::jint_from_data(data()+1);
740 else { ShouldNotReachHere(); }
741
742 _target = internal() ? address_from_scaled_offset(target_bits, addr())
743 : index_to_runtime_address (target_bits);
744 }
745
746
747 //// miscellaneous methods
748 oop* oop_Relocation::oop_addr() {
749 int n = _oop_index;
750 if (n == 0) {
751 // oop is stored in the code stream
752 return (oop*) pd_address_in_code();
753 } else {
754 // oop is stored in table at nmethod::oops_begin
755 return code()->oop_addr_at(n);
756 }
757 }
758
759
760 oop oop_Relocation::oop_value() {
761 oop v = *oop_addr();
762 // clean inline caches store a special pseudo-null
763 if (v == (oop)Universe::non_oop_word()) v = NULL;
764 return v;
765 }
766
767
768 void oop_Relocation::fix_oop_relocation() {
769 if (!oop_is_immediate()) {
770 // get the oop from the pool, and re-insert it into the instruction:
771 set_value(value());
772 }
773 }
774
775
776 RelocIterator virtual_call_Relocation::parse_ic(nmethod* &nm, address &ic_call, address &first_oop,
777 oop* &oop_addr, bool *is_optimized) {
778 assert(ic_call != NULL, "ic_call address must be set");
779 assert(ic_call != NULL || first_oop != NULL, "must supply a non-null input");
780 if (nm == NULL) {
781 CodeBlob* code;
782 if (ic_call != NULL) {
783 code = CodeCache::find_blob(ic_call);
784 } else if (first_oop != NULL) {
785 code = CodeCache::find_blob(first_oop);
786 }
787 nm = code->as_nmethod_or_null();
788 assert(nm != NULL, "address to parse must be in nmethod");
789 }
790 assert(ic_call == NULL || nm->contains(ic_call), "must be in nmethod");
791 assert(first_oop == NULL || nm->contains(first_oop), "must be in nmethod");
792
793 address oop_limit = NULL;
794
795 if (ic_call != NULL) {
796 // search for the ic_call at the given address
797 RelocIterator iter(nm, ic_call, ic_call+1);
798 bool ret = iter.next();
799 assert(ret == true, "relocInfo must exist at this address");
800 assert(iter.addr() == ic_call, "must find ic_call");
801 if (iter.type() == relocInfo::virtual_call_type) {
802 virtual_call_Relocation* r = iter.virtual_call_reloc();
803 first_oop = r->first_oop();
804 oop_limit = r->oop_limit();
805 *is_optimized = false;
806 } else {
807 assert(iter.type() == relocInfo::opt_virtual_call_type, "must be a virtual call");
808 *is_optimized = true;
809 oop_addr = NULL;
810 first_oop = NULL;
811 return iter;
812 }
813 }
814
815 // search for the first_oop, to get its oop_addr
816 RelocIterator all_oops(nm, first_oop);
817 RelocIterator iter = all_oops;
818 iter.set_limit(first_oop+1);
819 bool found_oop = false;
820 while (iter.next()) {
821 if (iter.type() == relocInfo::oop_type) {
822 assert(iter.addr() == first_oop, "must find first_oop");
823 oop_addr = iter.oop_reloc()->oop_addr();
824 found_oop = true;
825 break;
826 }
827 }
828 assert(found_oop, "must find first_oop");
829
830 bool did_reset = false;
831 while (ic_call == NULL) {
832 // search forward for the ic_call matching the given first_oop
833 while (iter.next()) {
834 if (iter.type() == relocInfo::virtual_call_type) {
835 virtual_call_Relocation* r = iter.virtual_call_reloc();
836 if (r->first_oop() == first_oop) {
837 ic_call = r->addr();
838 oop_limit = r->oop_limit();
839 break;
840 }
841 }
842 }
843 guarantee(!did_reset, "cannot find ic_call");
844 iter = RelocIterator(nm); // search the whole nmethod
845 did_reset = true;
846 }
847
848 assert(oop_limit != NULL && first_oop != NULL && ic_call != NULL, "");
849 all_oops.set_limit(oop_limit);
850 return all_oops;
851 }
852
853
854 address virtual_call_Relocation::first_oop() {
855 assert(_first_oop != NULL && _first_oop < addr(), "must precede ic_call");
856 return _first_oop;
857 }
858
859
860 address virtual_call_Relocation::oop_limit() {
861 if (_oop_limit == NULL)
862 return addr() + NativeCall::instruction_size;
863 else
864 return _oop_limit;
865 }
866
867
868
869 void virtual_call_Relocation::clear_inline_cache() {
870 // No stubs for ICs
871 // Clean IC
872 ResourceMark rm;
873 CompiledIC* icache = CompiledIC_at(this);
874 icache->set_to_clean();
875 }
876
877
878 void opt_virtual_call_Relocation::clear_inline_cache() {
879 // No stubs for ICs
880 // Clean IC
881 ResourceMark rm;
882 CompiledIC* icache = CompiledIC_at(this);
883 icache->set_to_clean();
884 }
885
886
887 address opt_virtual_call_Relocation::static_stub() {
888 // search for the static stub who points back to this static call
889 address static_call_addr = addr();
890 RelocIterator iter(code());
891 while (iter.next()) {
892 if (iter.type() == relocInfo::static_stub_type) {
893 if (iter.static_stub_reloc()->static_call() == static_call_addr) {
894 return iter.addr();
895 }
896 }
897 }
898 return NULL;
899 }
900
901
902 void static_call_Relocation::clear_inline_cache() {
903 // Safe call site info
904 CompiledStaticCall* handler = compiledStaticCall_at(this);
905 handler->set_to_clean();
906 }
907
908
909 address static_call_Relocation::static_stub() {
910 // search for the static stub who points back to this static call
911 address static_call_addr = addr();
912 RelocIterator iter(code());
913 while (iter.next()) {
914 if (iter.type() == relocInfo::static_stub_type) {
915 if (iter.static_stub_reloc()->static_call() == static_call_addr) {
916 return iter.addr();
917 }
918 }
919 }
920 return NULL;
921 }
922
923
924 void static_stub_Relocation::clear_inline_cache() {
925 // Call stub is only used when calling the interpreted code.
926 // It does not really need to be cleared, except that we want to clean out the methodoop.
927 CompiledStaticCall::set_stub_to_clean(this);
928 }
929
930
931 void external_word_Relocation::fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest) {
932 address target = _target;
933 if (target == NULL) {
934 // An absolute embedded reference to an external location,
935 // which means there is nothing to fix here.
936 return;
937 }
938 // Probably this reference is absolute, not relative, so the
939 // following is probably a no-op.
940 assert(src->section_index_of(target) == CodeBuffer::SECT_NONE, "sanity");
941 set_value(target);
942 }
943
944
945 address external_word_Relocation::target() {
946 address target = _target;
947 if (target == NULL) {
948 target = pd_get_address_from_code();
949 }
950 return target;
951 }
952
953
954 void internal_word_Relocation::fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest) {
955 address target = _target;
956 if (target == NULL) {
957 if (addr_in_const()) {
958 target = new_addr_for(*(address*)addr(), src, dest);
959 } else {
960 target = new_addr_for(pd_get_address_from_code(), src, dest);
961 }
962 }
963 set_value(target);
964 }
965
966
967 address internal_word_Relocation::target() {
968 address target = _target;
969 if (target == NULL) {
970 target = pd_get_address_from_code();
971 }
972 return target;
973 }
974
975
976 breakpoint_Relocation::breakpoint_Relocation(int kind, address target, bool internal) {
977 bool active = false;
978 bool enabled = (kind == initialization);
979 bool removable = (kind != safepoint);
980 bool settable = (target == NULL);
981
982 int bits = kind;
983 if (enabled) bits |= enabled_state;
984 if (internal) bits |= internal_attr;
985 if (removable) bits |= removable_attr;
986 if (settable) bits |= settable_attr;
987
988 _bits = bits | high_bit;
989 _target = target;
990
991 assert(this->kind() == kind, "kind encoded");
992 assert(this->enabled() == enabled, "enabled encoded");
993 assert(this->active() == active, "active encoded");
994 assert(this->internal() == internal, "internal encoded");
995 assert(this->removable() == removable, "removable encoded");
996 assert(this->settable() == settable, "settable encoded");
997 }
998
999
1000 address breakpoint_Relocation::target() const {
1001 return _target;
1002 }
1003
1004
1005 void breakpoint_Relocation::set_target(address x) {
1006 assert(settable(), "must be settable");
1007 jint target_bits =
1008 (jint)(internal() ? scaled_offset (x, addr())
1009 : runtime_address_to_index(x));
1010 short* p = &live_bits() + 1;
1011 p = add_jint(p, target_bits);
1012 assert(p == instrs(), "new target must fit");
1013 _target = x;
1014 }
1015
1016
1017 void breakpoint_Relocation::set_enabled(bool b) {
1018 if (enabled() == b) return;
1019
1020 if (b) {
1021 set_bits(bits() | enabled_state);
1022 } else {
1023 set_active(false); // remove the actual breakpoint insn, if any
1024 set_bits(bits() & ~enabled_state);
1025 }
1026 }
1027
1028
1029 void breakpoint_Relocation::set_active(bool b) {
1030 assert(!b || enabled(), "cannot activate a disabled breakpoint");
1031
1032 if (active() == b) return;
1033
1034 // %%% should probably seize a lock here (might not be the right lock)
1035 //MutexLockerEx ml_patch(Patching_lock, true);
1036 //if (active() == b) return; // recheck state after locking
1037
1038 if (b) {
1039 set_bits(bits() | active_state);
1040 if (instrlen() == 0)
1041 fatal("breakpoints in original code must be undoable");
1042 pd_swap_in_breakpoint (addr(), instrs(), instrlen());
1043 } else {
1044 set_bits(bits() & ~active_state);
1045 pd_swap_out_breakpoint(addr(), instrs(), instrlen());
1046 }
1047 }
1048
1049
1050 //---------------------------------------------------------------------------------
1051 // Non-product code
1052
1053 #ifndef PRODUCT
1054
1055 static const char* reloc_type_string(relocInfo::relocType t) {
1056 switch (t) {
1057 #define EACH_CASE(name) \
1058 case relocInfo::name##_type: \
1059 return #name;
1060
1061 APPLY_TO_RELOCATIONS(EACH_CASE);
1062 #undef EACH_CASE
1063
1064 case relocInfo::none:
1065 return "none";
1066 case relocInfo::data_prefix_tag:
1067 return "prefix";
1068 default:
1069 return "UNKNOWN RELOC TYPE";
1070 }
1071 }
1072
1073
1074 void RelocIterator::print_current() {
1075 if (!has_current()) {
1076 tty->print_cr("(no relocs)");
1077 return;
1078 }
1079 tty->print("relocInfo@" INTPTR_FORMAT " [type=%d(%s) addr=" INTPTR_FORMAT,
1080 _current, type(), reloc_type_string((relocInfo::relocType) type()), _addr);
1081 if (current()->format() != 0)
1082 tty->print(" format=%d", current()->format());
1083 if (datalen() == 1) {
1084 tty->print(" data=%d", data()[0]);
1085 } else if (datalen() > 0) {
1086 tty->print(" data={");
1087 for (int i = 0; i < datalen(); i++) {
1088 tty->print("%04x", data()[i] & 0xFFFF);
1089 }
1090 tty->print("}");
1091 }
1092 tty->print("]");
1093 switch (type()) {
1094 case relocInfo::oop_type:
1095 {
1096 oop_Relocation* r = oop_reloc();
1097 oop* oop_addr = NULL;
1098 oop raw_oop = NULL;
1099 oop oop_value = NULL;
1100 if (code() != NULL || r->oop_is_immediate()) {
1101 oop_addr = r->oop_addr();
1102 raw_oop = *oop_addr;
1103 oop_value = r->oop_value();
1104 }
1105 tty->print(" | [oop_addr=" INTPTR_FORMAT " *=" INTPTR_FORMAT " offset=%d]",
1106 oop_addr, (address)raw_oop, r->offset());
1107 // Do not print the oop by default--we want this routine to
1108 // work even during GC or other inconvenient times.
1109 if (WizardMode && oop_value != NULL) {
1110 tty->print("oop_value=" INTPTR_FORMAT ": ", (address)oop_value);
1111 oop_value->print_value_on(tty);
1112 }
1113 break;
1114 }
1115 case relocInfo::external_word_type:
1116 case relocInfo::internal_word_type:
1117 case relocInfo::section_word_type:
1118 {
1119 DataRelocation* r = (DataRelocation*) reloc();
1120 tty->print(" | [target=" INTPTR_FORMAT "]", r->value()); //value==target
1121 break;
1122 }
1123 case relocInfo::static_call_type:
1124 case relocInfo::runtime_call_type:
1125 {
1126 CallRelocation* r = (CallRelocation*) reloc();
1127 tty->print(" | [destination=" INTPTR_FORMAT "]", r->destination());
1128 break;
1129 }
1130 case relocInfo::virtual_call_type:
1131 {
1132 virtual_call_Relocation* r = (virtual_call_Relocation*) reloc();
1133 tty->print(" | [destination=" INTPTR_FORMAT " first_oop=" INTPTR_FORMAT " oop_limit=" INTPTR_FORMAT "]",
1134 r->destination(), r->first_oop(), r->oop_limit());
1135 break;
1136 }
1137 case relocInfo::static_stub_type:
1138 {
1139 static_stub_Relocation* r = (static_stub_Relocation*) reloc();
1140 tty->print(" | [static_call=" INTPTR_FORMAT "]", r->static_call());
1141 break;
1142 }
1143 }
1144 tty->cr();
1145 }
1146
1147
1148 void RelocIterator::print() {
1149 RelocIterator save_this = (*this);
1150 relocInfo* scan = _current;
1151 if (!has_current()) scan += 1; // nothing to scan here!
1152
1153 bool skip_next = has_current();
1154 bool got_next;
1155 while (true) {
1156 got_next = (skip_next || next());
1157 skip_next = false;
1158
1159 tty->print(" @" INTPTR_FORMAT ": ", scan);
1160 relocInfo* newscan = _current+1;
1161 if (!has_current()) newscan -= 1; // nothing to scan here!
1162 while (scan < newscan) {
1163 tty->print("%04x", *(short*)scan & 0xFFFF);
1164 scan++;
1165 }
1166 tty->cr();
1167
1168 if (!got_next) break;
1169 print_current();
1170 }
1171
1172 (*this) = save_this;
1173 }
1174
1175 // For the debugger:
1176 extern "C"
1177 void print_blob_locs(nmethod* nm) {
1178 nm->print();
1179 RelocIterator iter(nm);
1180 iter.print();
1181 }
1182 extern "C"
1183 void print_buf_locs(CodeBuffer* cb) {
1184 FlagSetting fs(PrintRelocations, true);
1185 cb->print();
1186 }
1187 #endif // !PRODUCT