src/share/vm/code/relocInfo.cpp

Wed, 27 Apr 2016 01:25:04 +0800

author
aoqi
date
Wed, 27 Apr 2016 01:25:04 +0800
changeset 0
f90c822e73f8
child 6876
710a3c8b516e
permissions
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http://hg.openjdk.java.net/jdk8u/jdk8u/hotspot/
changeset: 6782:28b50d07f6f8
tag: jdk8u25-b17

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

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