1 /*
   2  * Copyright (c) 1997, 2017, 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 void relocInfo::set_type(relocType t) {
  85   int old_offset = addr_offset();
  86   int old_format = format();
  87   (*this) = relocInfo(t, old_offset, old_format);
  88   assert(type()==(int)t, "sanity check");
  89   assert(addr_offset()==old_offset, "sanity check");
  90   assert(format()==old_format, "sanity check");
  91 }
  92 
  93 nmethod* RelocIterator::code_as_nmethod() const {
  94   return _code->as_nmethod();
  95 }
  96 
  97 void relocInfo::set_format(int f) {
  98   int old_offset = addr_offset();
  99   assert((f & format_mask) == f, "wrong format");
 100   _value = (_value & ~(format_mask << offset_width)) | (f << offset_width);
 101   assert(addr_offset()==old_offset, "sanity check");
 102 }
 103 
 104 
 105 void relocInfo::change_reloc_info_for_address(RelocIterator *itr, address pc, relocType old_type, relocType new_type) {
 106   bool found = false;
 107   while (itr->next() && !found) {
 108     if (itr->addr() == pc) {
 109       assert(itr->type()==old_type, "wrong relocInfo type found");
 110       itr->current()->set_type(new_type);
 111       found=true;
 112     }
 113   }
 114   assert(found, "no relocInfo found for pc");
 115 }
 116 
 117 
 118 void relocInfo::remove_reloc_info_for_address(RelocIterator *itr, address pc, relocType old_type) {
 119   change_reloc_info_for_address(itr, pc, old_type, none);
 120 }
 121 
 122 
 123 // ----------------------------------------------------------------------------------------------------
 124 // Implementation of RelocIterator
 125 
 126 void RelocIterator::initialize(CompiledMethod* nm, address begin, address limit) {
 127   initialize_misc();
 128 
 129   if (nm == NULL && begin != NULL) {
 130     // allow nmethod to be deduced from beginning address
 131     CodeBlob* cb = CodeCache::find_blob(begin);
 132     nm = (cb != NULL) ? cb->as_compiled_method_or_null() : NULL;
 133   }
 134   guarantee(nm != NULL, "must be able to deduce nmethod from other arguments");
 135 
 136   _code    = nm;
 137   _current = nm->relocation_begin() - 1;
 138   _end     = nm->relocation_end();
 139   _addr    = nm->content_begin();
 140 
 141   // Initialize code sections.
 142   _section_start[CodeBuffer::SECT_CONSTS] = nm->consts_begin();
 143   _section_start[CodeBuffer::SECT_INSTS ] = nm->insts_begin() ;
 144   _section_start[CodeBuffer::SECT_STUBS ] = nm->stub_begin()  ;
 145 
 146   _section_end  [CodeBuffer::SECT_CONSTS] = nm->consts_end()  ;
 147   _section_end  [CodeBuffer::SECT_INSTS ] = nm->insts_end()   ;
 148   _section_end  [CodeBuffer::SECT_STUBS ] = nm->stub_end()    ;
 149 
 150   assert(!has_current(), "just checking");
 151   assert(begin == NULL || begin >= nm->code_begin(), "in bounds");
 152   assert(limit == NULL || limit <= nm->code_end(),   "in bounds");
 153   set_limits(begin, limit);
 154 }
 155 
 156 
 157 RelocIterator::RelocIterator(CodeSection* cs, address begin, address limit) {
 158   initialize_misc();
 159 
 160   _current = cs->locs_start()-1;
 161   _end     = cs->locs_end();
 162   _addr    = cs->start();
 163   _code    = NULL; // Not cb->blob();
 164 
 165   CodeBuffer* cb = cs->outer();
 166   assert((int) SECT_LIMIT == CodeBuffer::SECT_LIMIT, "my copy must be equal");
 167   for (int n = (int) CodeBuffer::SECT_FIRST; n < (int) CodeBuffer::SECT_LIMIT; n++) {
 168     CodeSection* cs = cb->code_section(n);
 169     _section_start[n] = cs->start();
 170     _section_end  [n] = cs->end();
 171   }
 172 
 173   assert(!has_current(), "just checking");
 174 
 175   assert(begin == NULL || begin >= cs->start(), "in bounds");
 176   assert(limit == NULL || limit <= cs->end(),   "in bounds");
 177   set_limits(begin, limit);
 178 }
 179 
 180 
 181 enum { indexCardSize = 128 };
 182 struct RelocIndexEntry {
 183   jint addr_offset;          // offset from header_end of an addr()
 184   jint reloc_offset;         // offset from header_end of a relocInfo (prefix)
 185 };
 186 
 187 
 188 bool RelocIterator::addr_in_const() const {
 189   const int n = CodeBuffer::SECT_CONSTS;
 190   return section_start(n) <= addr() && addr() < section_end(n);
 191 }
 192 
 193 
 194 void RelocIterator::set_limits(address begin, address limit) {
 195   _limit = limit;
 196 
 197   // the limit affects this next stuff:
 198   if (begin != NULL) {
 199     relocInfo* backup;
 200     address    backup_addr;
 201     while (true) {
 202       backup      = _current;
 203       backup_addr = _addr;
 204       if (!next() || addr() >= begin) break;
 205     }
 206     // At this point, either we are at the first matching record,
 207     // or else there is no such record, and !has_current().
 208     // In either case, revert to the immediatly preceding state.
 209     _current = backup;
 210     _addr    = backup_addr;
 211     set_has_current(false);
 212   }
 213 }
 214 
 215 
 216 void RelocIterator::set_limit(address limit) {
 217   address code_end = (address)code() + code()->size();
 218   assert(limit == NULL || limit <= code_end, "in bounds");
 219   _limit = limit;
 220 }
 221 
 222 // All the strange bit-encodings are in here.
 223 // The idea is to encode relocation data which are small integers
 224 // very efficiently (a single extra halfword).  Larger chunks of
 225 // relocation data need a halfword header to hold their size.
 226 void RelocIterator::advance_over_prefix() {
 227   if (_current->is_datalen()) {
 228     _data    = (short*) _current->data();
 229     _datalen =          _current->datalen();
 230     _current += _datalen + 1;   // skip the embedded data & header
 231   } else {
 232     _databuf = _current->immediate();
 233     _data = &_databuf;
 234     _datalen = 1;
 235     _current++;                 // skip the header
 236   }
 237   // The client will see the following relocInfo, whatever that is.
 238   // It is the reloc to which the preceding data applies.
 239 }
 240 
 241 
 242 void RelocIterator::initialize_misc() {
 243   set_has_current(false);
 244   for (int i = (int) CodeBuffer::SECT_FIRST; i < (int) CodeBuffer::SECT_LIMIT; i++) {
 245     _section_start[i] = NULL;  // these will be lazily computed, if needed
 246     _section_end  [i] = NULL;
 247   }
 248 }
 249 
 250 
 251 Relocation* RelocIterator::reloc() {
 252   // (take the "switch" out-of-line)
 253   relocInfo::relocType t = type();
 254   if (false) {}
 255   #define EACH_TYPE(name)                             \
 256   else if (t == relocInfo::name##_type) {             \
 257     return name##_reloc();                            \
 258   }
 259   APPLY_TO_RELOCATIONS(EACH_TYPE);
 260   #undef EACH_TYPE
 261   assert(t == relocInfo::none, "must be padding");
 262   return new(_rh) Relocation();
 263 }
 264 
 265 
 266 //////// Methods for flyweight Relocation types
 267 
 268 
 269 RelocationHolder RelocationHolder::plus(int offset) const {
 270   if (offset != 0) {
 271     switch (type()) {
 272     case relocInfo::none:
 273       break;
 274     case relocInfo::oop_type:
 275       {
 276         oop_Relocation* r = (oop_Relocation*)reloc();
 277         return oop_Relocation::spec(r->oop_index(), r->offset() + offset);
 278       }
 279     case relocInfo::metadata_type:
 280       {
 281         metadata_Relocation* r = (metadata_Relocation*)reloc();
 282         return metadata_Relocation::spec(r->metadata_index(), r->offset() + offset);
 283       }
 284     default:
 285       ShouldNotReachHere();
 286     }
 287   }
 288   return (*this);
 289 }
 290 
 291 
 292 void Relocation::guarantee_size() {
 293   guarantee(false, "Make _relocbuf bigger!");
 294 }
 295 
 296     // some relocations can compute their own values
 297 address Relocation::value() {
 298   ShouldNotReachHere();
 299   return NULL;
 300 }
 301 
 302 
 303 void Relocation::set_value(address x) {
 304   ShouldNotReachHere();
 305 }
 306 
 307 void Relocation::const_set_data_value(address x) {
 308 #ifdef _LP64
 309   if (format() == relocInfo::narrow_oop_in_const) {
 310     *(narrowOop*)addr() = oopDesc::encode_heap_oop((oop) x);
 311   } else {
 312 #endif
 313     *(address*)addr() = x;
 314 #ifdef _LP64
 315   }
 316 #endif
 317 }
 318 
 319 void Relocation::const_verify_data_value(address x) {
 320 #ifdef _LP64
 321   if (format() == relocInfo::narrow_oop_in_const) {
 322     guarantee(*(narrowOop*)addr() == oopDesc::encode_heap_oop((oop) x), "must agree");
 323   } else {
 324 #endif
 325     guarantee(*(address*)addr() == x, "must agree");
 326 #ifdef _LP64
 327   }
 328 #endif
 329 }
 330 
 331 
 332 RelocationHolder Relocation::spec_simple(relocInfo::relocType rtype) {
 333   if (rtype == relocInfo::none)  return RelocationHolder::none;
 334   relocInfo ri = relocInfo(rtype, 0);
 335   RelocIterator itr;
 336   itr.set_current(ri);
 337   itr.reloc();
 338   return itr._rh;
 339 }
 340 
 341 address Relocation::old_addr_for(address newa,
 342                                  const CodeBuffer* src, CodeBuffer* dest) {
 343   int sect = dest->section_index_of(newa);
 344   guarantee(sect != CodeBuffer::SECT_NONE, "lost track of this address");
 345   address ostart = src->code_section(sect)->start();
 346   address nstart = dest->code_section(sect)->start();
 347   return ostart + (newa - nstart);
 348 }
 349 
 350 address Relocation::new_addr_for(address olda,
 351                                  const CodeBuffer* src, CodeBuffer* dest) {
 352   debug_only(const CodeBuffer* src0 = src);
 353   int sect = CodeBuffer::SECT_NONE;
 354   // Look for olda in the source buffer, and all previous incarnations
 355   // if the source buffer has been expanded.
 356   for (; src != NULL; src = src->before_expand()) {
 357     sect = src->section_index_of(olda);
 358     if (sect != CodeBuffer::SECT_NONE)  break;
 359   }
 360   guarantee(sect != CodeBuffer::SECT_NONE, "lost track of this address");
 361   address ostart = src->code_section(sect)->start();
 362   address nstart = dest->code_section(sect)->start();
 363   return nstart + (olda - ostart);
 364 }
 365 
 366 void Relocation::normalize_address(address& addr, const CodeSection* dest, bool allow_other_sections) {
 367   address addr0 = addr;
 368   if (addr0 == NULL || dest->allocates2(addr0))  return;
 369   CodeBuffer* cb = dest->outer();
 370   addr = new_addr_for(addr0, cb, cb);
 371   assert(allow_other_sections || dest->contains2(addr),
 372          "addr must be in required section");
 373 }
 374 
 375 
 376 void CallRelocation::set_destination(address x) {
 377   pd_set_call_destination(x);
 378 }
 379 
 380 void CallRelocation::fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest) {
 381   // Usually a self-relative reference to an external routine.
 382   // On some platforms, the reference is absolute (not self-relative).
 383   // The enhanced use of pd_call_destination sorts this all out.
 384   address orig_addr = old_addr_for(addr(), src, dest);
 385   address callee    = pd_call_destination(orig_addr);
 386   // Reassert the callee address, this time in the new copy of the code.
 387   pd_set_call_destination(callee);
 388 }
 389 
 390 
 391 //// pack/unpack methods
 392 
 393 void oop_Relocation::pack_data_to(CodeSection* dest) {
 394   short* p = (short*) dest->locs_end();
 395   p = pack_2_ints_to(p, _oop_index, _offset);
 396   dest->set_locs_end((relocInfo*) p);
 397 }
 398 
 399 
 400 void oop_Relocation::unpack_data() {
 401   unpack_2_ints(_oop_index, _offset);
 402 }
 403 
 404 void metadata_Relocation::pack_data_to(CodeSection* dest) {
 405   short* p = (short*) dest->locs_end();
 406   p = pack_2_ints_to(p, _metadata_index, _offset);
 407   dest->set_locs_end((relocInfo*) p);
 408 }
 409 
 410 
 411 void metadata_Relocation::unpack_data() {
 412   unpack_2_ints(_metadata_index, _offset);
 413 }
 414 
 415 
 416 void virtual_call_Relocation::pack_data_to(CodeSection* dest) {
 417   short*  p     = (short*) dest->locs_end();
 418   address point =          dest->locs_point();
 419 
 420   normalize_address(_cached_value, dest);
 421   jint x0 = scaled_offset_null_special(_cached_value, point);
 422   p = pack_2_ints_to(p, x0, _method_index);
 423   dest->set_locs_end((relocInfo*) p);
 424 }
 425 
 426 
 427 void virtual_call_Relocation::unpack_data() {
 428   jint x0 = 0;
 429   unpack_2_ints(x0, _method_index);
 430   address point = addr();
 431   _cached_value = x0==0? NULL: address_from_scaled_offset(x0, point);
 432 }
 433 
 434 void runtime_call_w_cp_Relocation::pack_data_to(CodeSection * dest) {
 435   short* p = pack_1_int_to((short *)dest->locs_end(), (jint)(_offset >> 2));
 436   dest->set_locs_end((relocInfo*) p);
 437 }
 438 
 439 void runtime_call_w_cp_Relocation::unpack_data() {
 440   _offset = unpack_1_int() << 2;
 441 }
 442 
 443 void static_stub_Relocation::pack_data_to(CodeSection* dest) {
 444   short* p = (short*) dest->locs_end();
 445   CodeSection* insts = dest->outer()->insts();
 446   normalize_address(_static_call, insts);
 447   jint is_aot = _is_aot ? 1 : 0;
 448   p = pack_2_ints_to(p, scaled_offset(_static_call, insts->start()), is_aot);
 449   dest->set_locs_end((relocInfo*) p);
 450 }
 451 
 452 void static_stub_Relocation::unpack_data() {
 453   address base = binding()->section_start(CodeBuffer::SECT_INSTS);
 454   jint offset;
 455   jint is_aot;
 456   unpack_2_ints(offset, is_aot);
 457   _static_call = address_from_scaled_offset(offset, base);
 458   _is_aot = (is_aot == 1);
 459 }
 460 
 461 void trampoline_stub_Relocation::pack_data_to(CodeSection* dest ) {
 462   short* p = (short*) dest->locs_end();
 463   CodeSection* insts = dest->outer()->insts();
 464   normalize_address(_owner, insts);
 465   p = pack_1_int_to(p, scaled_offset(_owner, insts->start()));
 466   dest->set_locs_end((relocInfo*) p);
 467 }
 468 
 469 void trampoline_stub_Relocation::unpack_data() {
 470   address base = binding()->section_start(CodeBuffer::SECT_INSTS);
 471   _owner = address_from_scaled_offset(unpack_1_int(), base);
 472 }
 473 
 474 void external_word_Relocation::pack_data_to(CodeSection* dest) {
 475   short* p = (short*) dest->locs_end();
 476 #ifndef _LP64
 477   p = pack_1_int_to(p, (int32_t) (intptr_t)_target);
 478 #else
 479   jlong t = (jlong) _target;
 480   int32_t lo = low(t);
 481   int32_t hi = high(t);
 482   p = pack_2_ints_to(p, lo, hi);
 483 #endif /* _LP64 */
 484   dest->set_locs_end((relocInfo*) p);
 485 }
 486 
 487 
 488 void external_word_Relocation::unpack_data() {
 489 #ifndef _LP64
 490   _target = (address) (intptr_t)unpack_1_int();
 491 #else
 492   int32_t lo, hi;
 493   unpack_2_ints(lo, hi);
 494   jlong t = jlong_from(hi, lo);;
 495   _target = (address) t;
 496 #endif /* _LP64 */
 497 }
 498 
 499 
 500 void internal_word_Relocation::pack_data_to(CodeSection* dest) {
 501   short* p = (short*) dest->locs_end();
 502   normalize_address(_target, dest, true);
 503 
 504   // Check whether my target address is valid within this section.
 505   // If not, strengthen the relocation type to point to another section.
 506   int sindex = _section;
 507   if (sindex == CodeBuffer::SECT_NONE && _target != NULL
 508       && (!dest->allocates(_target) || _target == dest->locs_point())) {
 509     sindex = dest->outer()->section_index_of(_target);
 510     guarantee(sindex != CodeBuffer::SECT_NONE, "must belong somewhere");
 511     relocInfo* base = dest->locs_end() - 1;
 512     assert(base->type() == this->type(), "sanity");
 513     // Change the written type, to be section_word_type instead.
 514     base->set_type(relocInfo::section_word_type);
 515   }
 516 
 517   // Note: An internal_word relocation cannot refer to its own instruction,
 518   // because we reserve "0" to mean that the pointer itself is embedded
 519   // in the code stream.  We use a section_word relocation for such cases.
 520 
 521   if (sindex == CodeBuffer::SECT_NONE) {
 522     assert(type() == relocInfo::internal_word_type, "must be base class");
 523     guarantee(_target == NULL || dest->allocates2(_target), "must be within the given code section");
 524     jint x0 = scaled_offset_null_special(_target, dest->locs_point());
 525     assert(!(x0 == 0 && _target != NULL), "correct encoding of null target");
 526     p = pack_1_int_to(p, x0);
 527   } else {
 528     assert(_target != NULL, "sanity");
 529     CodeSection* sect = dest->outer()->code_section(sindex);
 530     guarantee(sect->allocates2(_target), "must be in correct section");
 531     address base = sect->start();
 532     jint offset = scaled_offset(_target, base);
 533     assert((uint)sindex < (uint)CodeBuffer::SECT_LIMIT, "sanity");
 534     assert(CodeBuffer::SECT_LIMIT <= (1 << section_width), "section_width++");
 535     p = pack_1_int_to(p, (offset << section_width) | sindex);
 536   }
 537 
 538   dest->set_locs_end((relocInfo*) p);
 539 }
 540 
 541 
 542 void internal_word_Relocation::unpack_data() {
 543   jint x0 = unpack_1_int();
 544   _target = x0==0? NULL: address_from_scaled_offset(x0, addr());
 545   _section = CodeBuffer::SECT_NONE;
 546 }
 547 
 548 
 549 void section_word_Relocation::unpack_data() {
 550   jint    x      = unpack_1_int();
 551   jint    offset = (x >> section_width);
 552   int     sindex = (x & ((1<<section_width)-1));
 553   address base   = binding()->section_start(sindex);
 554 
 555   _section = sindex;
 556   _target  = address_from_scaled_offset(offset, base);
 557 }
 558 
 559 //// miscellaneous methods
 560 oop* oop_Relocation::oop_addr() {
 561   int n = _oop_index;
 562   if (n == 0) {
 563     // oop is stored in the code stream
 564     return (oop*) pd_address_in_code();
 565   } else {
 566     // oop is stored in table at nmethod::oops_begin
 567     return code()->oop_addr_at(n);
 568   }
 569 }
 570 
 571 
 572 oop oop_Relocation::oop_value() {
 573   oop v = *oop_addr();
 574   // clean inline caches store a special pseudo-null
 575   if (v == (oop)Universe::non_oop_word())  v = NULL;
 576   return v;
 577 }
 578 
 579 
 580 void oop_Relocation::fix_oop_relocation() {
 581   if (!oop_is_immediate()) {
 582     // get the oop from the pool, and re-insert it into the instruction:
 583     set_value(value());
 584   }
 585 }
 586 
 587 
 588 void oop_Relocation::verify_oop_relocation() {
 589   if (!oop_is_immediate()) {
 590     // get the oop from the pool, and re-insert it into the instruction:
 591     verify_value(value());
 592   }
 593 }
 594 
 595 // meta data versions
 596 Metadata** metadata_Relocation::metadata_addr() {
 597   int n = _metadata_index;
 598   if (n == 0) {
 599     // metadata is stored in the code stream
 600     return (Metadata**) pd_address_in_code();
 601     } else {
 602     // metadata is stored in table at nmethod::metadatas_begin
 603     return code()->metadata_addr_at(n);
 604     }
 605   }
 606 
 607 
 608 Metadata* metadata_Relocation::metadata_value() {
 609   Metadata* v = *metadata_addr();
 610   // clean inline caches store a special pseudo-null
 611   if (v == (Metadata*)Universe::non_oop_word())  v = NULL;
 612   return v;
 613   }
 614 
 615 
 616 void metadata_Relocation::fix_metadata_relocation() {
 617   if (!metadata_is_immediate()) {
 618     // get the metadata from the pool, and re-insert it into the instruction:
 619     pd_fix_value(value());
 620   }
 621 }
 622 
 623 
 624 void metadata_Relocation::verify_metadata_relocation() {
 625   if (!metadata_is_immediate()) {
 626     // get the metadata from the pool, and re-insert it into the instruction:
 627     verify_value(value());
 628   }
 629 }
 630 
 631 address virtual_call_Relocation::cached_value() {
 632   assert(_cached_value != NULL && _cached_value < addr(), "must precede ic_call");
 633   return _cached_value;
 634 }
 635 
 636 Method* virtual_call_Relocation::method_value() {
 637   CompiledMethod* cm = code();
 638   if (cm == NULL) return (Method*)NULL;
 639   Metadata* m = cm->metadata_at(_method_index);
 640   assert(m != NULL || _method_index == 0, "should be non-null for non-zero index");
 641   assert(m == NULL || m->is_method(), "not a method");
 642   return (Method*)m;
 643 }
 644 
 645 void virtual_call_Relocation::clear_inline_cache() {
 646   // No stubs for ICs
 647   // Clean IC
 648   ResourceMark rm;
 649   CompiledIC* icache = CompiledIC_at(this);
 650   icache->set_to_clean();
 651 }
 652 
 653 
 654 void opt_virtual_call_Relocation::pack_data_to(CodeSection* dest) {
 655   short* p = (short*) dest->locs_end();
 656   p = pack_1_int_to(p, _method_index);
 657   dest->set_locs_end((relocInfo*) p);
 658 }
 659 
 660 void opt_virtual_call_Relocation::unpack_data() {
 661   _method_index = unpack_1_int();
 662 }
 663 
 664 Method* opt_virtual_call_Relocation::method_value() {
 665   CompiledMethod* cm = code();
 666   if (cm == NULL) return (Method*)NULL;
 667   Metadata* m = cm->metadata_at(_method_index);
 668   assert(m != NULL || _method_index == 0, "should be non-null for non-zero index");
 669   assert(m == NULL || m->is_method(), "not a method");
 670   return (Method*)m;
 671 }
 672 
 673 void opt_virtual_call_Relocation::clear_inline_cache() {
 674   // No stubs for ICs
 675   // Clean IC
 676   ResourceMark rm;
 677   CompiledIC* icache = CompiledIC_at(this);
 678   icache->set_to_clean();
 679 }
 680 
 681 
 682 address opt_virtual_call_Relocation::static_stub(bool is_aot) {
 683   // search for the static stub who points back to this static call
 684   address static_call_addr = addr();
 685   RelocIterator iter(code());
 686   while (iter.next()) {
 687     if (iter.type() == relocInfo::static_stub_type) {
 688       static_stub_Relocation* stub_reloc = iter.static_stub_reloc();
 689       if (stub_reloc->static_call() == static_call_addr && stub_reloc->is_aot() == is_aot) {
 690         return iter.addr();
 691       }
 692     }
 693   }
 694   return NULL;
 695 }
 696 
 697 Method* static_call_Relocation::method_value() {
 698   CompiledMethod* cm = code();
 699   if (cm == NULL) return (Method*)NULL;
 700   Metadata* m = cm->metadata_at(_method_index);
 701   assert(m != NULL || _method_index == 0, "should be non-null for non-zero index");
 702   assert(m == NULL || m->is_method(), "not a method");
 703   return (Method*)m;
 704 }
 705 
 706 void static_call_Relocation::pack_data_to(CodeSection* dest) {
 707   short* p = (short*) dest->locs_end();
 708   p = pack_1_int_to(p, _method_index);
 709   dest->set_locs_end((relocInfo*) p);
 710 }
 711 
 712 void static_call_Relocation::unpack_data() {
 713   _method_index = unpack_1_int();
 714 }
 715 
 716 void static_call_Relocation::clear_inline_cache() {
 717   // Safe call site info
 718   CompiledStaticCall* handler = this->code()->compiledStaticCall_at(this);
 719   handler->set_to_clean();
 720 }
 721 
 722 
 723 address static_call_Relocation::static_stub(bool is_aot) {
 724   // search for the static stub who points back to this static call
 725   address static_call_addr = addr();
 726   RelocIterator iter(code());
 727   while (iter.next()) {
 728     if (iter.type() == relocInfo::static_stub_type) {
 729       static_stub_Relocation* stub_reloc = iter.static_stub_reloc();
 730       if (stub_reloc->static_call() == static_call_addr && stub_reloc->is_aot() == is_aot) {
 731         return iter.addr();
 732       }
 733     }
 734   }
 735   return NULL;
 736 }
 737 
 738 // Finds the trampoline address for a call. If no trampoline stub is
 739 // found NULL is returned which can be handled by the caller.
 740 address trampoline_stub_Relocation::get_trampoline_for(address call, nmethod* code) {
 741   // There are no relocations available when the code gets relocated
 742   // because of CodeBuffer expansion.
 743   if (code->relocation_size() == 0)
 744     return NULL;
 745 
 746   RelocIterator iter(code, call);
 747   while (iter.next()) {
 748     if (iter.type() == relocInfo::trampoline_stub_type) {
 749       if (iter.trampoline_stub_reloc()->owner() == call) {
 750         return iter.addr();
 751       }
 752     }
 753   }
 754 
 755   return NULL;
 756 }
 757 
 758 void static_stub_Relocation::clear_inline_cache() {
 759   // Call stub is only used when calling the interpreted code.
 760   // It does not really need to be cleared, except that we want to clean out the methodoop.
 761   CompiledDirectStaticCall::set_stub_to_clean(this);
 762 }
 763 
 764 
 765 void external_word_Relocation::fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest) {
 766   address target = _target;
 767   if (target == NULL) {
 768     // An absolute embedded reference to an external location,
 769     // which means there is nothing to fix here.
 770     return;
 771   }
 772   // Probably this reference is absolute, not relative, so the
 773   // following is probably a no-op.
 774   assert(src->section_index_of(target) == CodeBuffer::SECT_NONE, "sanity");
 775   set_value(target);
 776 }
 777 
 778 
 779 address external_word_Relocation::target() {
 780   address target = _target;
 781   if (target == NULL) {
 782     target = pd_get_address_from_code();
 783   }
 784   return target;
 785 }
 786 
 787 
 788 void internal_word_Relocation::fix_relocation_after_move(const CodeBuffer* src, CodeBuffer* dest) {
 789   address target = _target;
 790   if (target == NULL) {
 791     target = new_addr_for(this->target(), src, dest);
 792   }
 793   set_value(target);
 794 }
 795 
 796 
 797 address internal_word_Relocation::target() {
 798   address target = _target;
 799   if (target == NULL) {
 800     if (addr_in_const()) {
 801       target = *(address*)addr();
 802     } else {
 803       target = pd_get_address_from_code();
 804     }
 805   }
 806   return target;
 807 }
 808 
 809 //---------------------------------------------------------------------------------
 810 // Non-product code
 811 
 812 #ifndef PRODUCT
 813 
 814 static const char* reloc_type_string(relocInfo::relocType t) {
 815   switch (t) {
 816   #define EACH_CASE(name) \
 817   case relocInfo::name##_type: \
 818     return #name;
 819 
 820   APPLY_TO_RELOCATIONS(EACH_CASE);
 821   #undef EACH_CASE
 822 
 823   case relocInfo::none:
 824     return "none";
 825   case relocInfo::data_prefix_tag:
 826     return "prefix";
 827   default:
 828     return "UNKNOWN RELOC TYPE";
 829   }
 830 }
 831 
 832 
 833 void RelocIterator::print_current() {
 834   if (!has_current()) {
 835     tty->print_cr("(no relocs)");
 836     return;
 837   }
 838   tty->print("relocInfo@" INTPTR_FORMAT " [type=%d(%s) addr=" INTPTR_FORMAT " offset=%d",
 839              p2i(_current), type(), reloc_type_string((relocInfo::relocType) type()), p2i(_addr), _current->addr_offset());
 840   if (current()->format() != 0)
 841     tty->print(" format=%d", current()->format());
 842   if (datalen() == 1) {
 843     tty->print(" data=%d", data()[0]);
 844   } else if (datalen() > 0) {
 845     tty->print(" data={");
 846     for (int i = 0; i < datalen(); i++) {
 847       tty->print("%04x", data()[i] & 0xFFFF);
 848     }
 849     tty->print("}");
 850   }
 851   tty->print("]");
 852   switch (type()) {
 853   case relocInfo::oop_type:
 854     {
 855       oop_Relocation* r = oop_reloc();
 856       oop* oop_addr  = NULL;
 857       oop  raw_oop   = NULL;
 858       oop  oop_value = NULL;
 859       if (code() != NULL || r->oop_is_immediate()) {
 860         oop_addr  = r->oop_addr();
 861         raw_oop   = *oop_addr;
 862         oop_value = r->oop_value();
 863       }
 864       tty->print(" | [oop_addr=" INTPTR_FORMAT " *=" INTPTR_FORMAT " offset=%d]",
 865                  p2i(oop_addr), p2i(raw_oop), r->offset());
 866       // Do not print the oop by default--we want this routine to
 867       // work even during GC or other inconvenient times.
 868       if (WizardMode && oop_value != NULL) {
 869         tty->print("oop_value=" INTPTR_FORMAT ": ", p2i(oop_value));
 870         if (oop_value->is_oop()) {
 871           oop_value->print_value_on(tty);
 872         }
 873       }
 874       break;
 875     }
 876   case relocInfo::metadata_type:
 877     {
 878       metadata_Relocation* r = metadata_reloc();
 879       Metadata** metadata_addr  = NULL;
 880       Metadata*    raw_metadata   = NULL;
 881       Metadata*    metadata_value = NULL;
 882       if (code() != NULL || r->metadata_is_immediate()) {
 883         metadata_addr  = r->metadata_addr();
 884         raw_metadata   = *metadata_addr;
 885         metadata_value = r->metadata_value();
 886       }
 887       tty->print(" | [metadata_addr=" INTPTR_FORMAT " *=" INTPTR_FORMAT " offset=%d]",
 888                  p2i(metadata_addr), p2i(raw_metadata), r->offset());
 889       if (metadata_value != NULL) {
 890         tty->print("metadata_value=" INTPTR_FORMAT ": ", p2i(metadata_value));
 891         metadata_value->print_value_on(tty);
 892       }
 893       break;
 894     }
 895   case relocInfo::external_word_type:
 896   case relocInfo::internal_word_type:
 897   case relocInfo::section_word_type:
 898     {
 899       DataRelocation* r = (DataRelocation*) reloc();
 900       tty->print(" | [target=" INTPTR_FORMAT "]", p2i(r->value())); //value==target
 901       break;
 902     }
 903   case relocInfo::static_call_type:
 904     {
 905       static_call_Relocation* r = (static_call_Relocation*) reloc();
 906       tty->print(" | [destination=" INTPTR_FORMAT " metadata=" INTPTR_FORMAT "]",
 907                  p2i(r->destination()), p2i(r->method_value()));
 908       break;
 909     }
 910   case relocInfo::runtime_call_type:
 911   case relocInfo::runtime_call_w_cp_type:
 912     {
 913       CallRelocation* r = (CallRelocation*) reloc();
 914       tty->print(" | [destination=" INTPTR_FORMAT "]", p2i(r->destination()));
 915       break;
 916     }
 917   case relocInfo::virtual_call_type:
 918     {
 919       virtual_call_Relocation* r = (virtual_call_Relocation*) reloc();
 920       tty->print(" | [destination=" INTPTR_FORMAT " cached_value=" INTPTR_FORMAT " metadata=" INTPTR_FORMAT "]",
 921                  p2i(r->destination()), p2i(r->cached_value()), p2i(r->method_value()));
 922       break;
 923     }
 924   case relocInfo::static_stub_type:
 925     {
 926       static_stub_Relocation* r = (static_stub_Relocation*) reloc();
 927       tty->print(" | [static_call=" INTPTR_FORMAT "]", p2i(r->static_call()));
 928       break;
 929     }
 930   case relocInfo::trampoline_stub_type:
 931     {
 932       trampoline_stub_Relocation* r = (trampoline_stub_Relocation*) reloc();
 933       tty->print(" | [trampoline owner=" INTPTR_FORMAT "]", p2i(r->owner()));
 934       break;
 935     }
 936   case relocInfo::opt_virtual_call_type:
 937     {
 938       opt_virtual_call_Relocation* r = (opt_virtual_call_Relocation*) reloc();
 939       tty->print(" | [destination=" INTPTR_FORMAT " metadata=" INTPTR_FORMAT "]",
 940                  p2i(r->destination()), p2i(r->method_value()));
 941       break;
 942     }
 943   default:
 944     break;
 945   }
 946   tty->cr();
 947 }
 948 
 949 
 950 void RelocIterator::print() {
 951   RelocIterator save_this = (*this);
 952   relocInfo* scan = _current;
 953   if (!has_current())  scan += 1;  // nothing to scan here!
 954 
 955   bool skip_next = has_current();
 956   bool got_next;
 957   while (true) {
 958     got_next = (skip_next || next());
 959     skip_next = false;
 960 
 961     tty->print("         @" INTPTR_FORMAT ": ", p2i(scan));
 962     relocInfo* newscan = _current+1;
 963     if (!has_current())  newscan -= 1;  // nothing to scan here!
 964     while (scan < newscan) {
 965       tty->print("%04x", *(short*)scan & 0xFFFF);
 966       scan++;
 967     }
 968     tty->cr();
 969 
 970     if (!got_next)  break;
 971     print_current();
 972   }
 973 
 974   (*this) = save_this;
 975 }
 976 
 977 // For the debugger:
 978 extern "C"
 979 void print_blob_locs(nmethod* nm) {
 980   nm->print();
 981   RelocIterator iter(nm);
 982   iter.print();
 983 }
 984 extern "C"
 985 void print_buf_locs(CodeBuffer* cb) {
 986   FlagSetting fs(PrintRelocations, true);
 987   cb->print();
 988 }
 989 #endif // !PRODUCT