1 /*
   2  * Copyright (c) 1997, 2019, 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 "interpreter/interpreter.hpp"
  27 #include "memory/resourceArea.hpp"
  28 #include "oops/markOop.hpp"
  29 #include "oops/method.hpp"
  30 #include "oops/oop.inline.hpp"
  31 #include "prims/methodHandles.hpp"
  32 #include "runtime/frame.inline.hpp"
  33 #include "runtime/handles.inline.hpp"
  34 #include "runtime/javaCalls.hpp"
  35 #include "runtime/monitorChunk.hpp"
  36 #include "runtime/os.inline.hpp"
  37 #include "runtime/signature.hpp"
  38 #include "runtime/stubCodeGenerator.hpp"
  39 #include "runtime/stubRoutines.hpp"
  40 #include "vmreg_x86.inline.hpp"
  41 #ifdef COMPILER1
  42 #include "c1/c1_Runtime1.hpp"
  43 #include "runtime/vframeArray.hpp"
  44 #endif
  45 
  46 #ifdef ASSERT
  47 void RegisterMap::check_location_valid() {
  48 }
  49 #endif
  50 
  51 // Profiling/safepoint support
  52 
  53 bool frame::safe_for_sender(JavaThread *thread) {
  54   address   sp = (address)_sp;
  55   address   fp = (address)_fp;
  56   address   unextended_sp = (address)_unextended_sp;
  57 
  58   // consider stack guards when trying to determine "safe" stack pointers
  59   static size_t stack_guard_size = os::uses_stack_guard_pages() ?
  60     JavaThread::stack_red_zone_size() + JavaThread::stack_yellow_zone_size() : 0;
  61   size_t usable_stack_size = thread->stack_size() - stack_guard_size;
  62 
  63   // sp must be within the usable part of the stack (not in guards)
  64   bool sp_safe = (sp < thread->stack_base()) &&
  65                  (sp >= thread->stack_base() - usable_stack_size);
  66 
  67 
  68   if (!sp_safe) {
  69     return false;
  70   }
  71 
  72   // unextended sp must be within the stack and above or equal sp
  73   bool unextended_sp_safe = (unextended_sp < thread->stack_base()) &&
  74                             (unextended_sp >= sp);
  75 
  76   if (!unextended_sp_safe) {
  77     return false;
  78   }
  79 
  80   // an fp must be within the stack and above (but not equal) sp
  81   // second evaluation on fp+ is added to handle situation where fp is -1
  82   bool fp_safe = (fp < thread->stack_base() && (fp > sp) && (((fp + (return_addr_offset * sizeof(void*))) < thread->stack_base())));
  83 
  84   // We know sp/unextended_sp are safe only fp is questionable here
  85 
  86   // If the current frame is known to the code cache then we can attempt to
  87   // to construct the sender and do some validation of it. This goes a long way
  88   // toward eliminating issues when we get in frame construction code
  89 
  90   if (_cb != NULL ) {
  91 
  92     // First check if frame is complete and tester is reliable
  93     // Unfortunately we can only check frame complete for runtime stubs and nmethod
  94     // other generic buffer blobs are more problematic so we just assume they are
  95     // ok. adapter blobs never have a frame complete and are never ok.
  96 
  97     if (!_cb->is_frame_complete_at(_pc)) {
  98       if (_cb->is_compiled() || _cb->is_adapter_blob() || _cb->is_runtime_stub()) {
  99         return false;
 100       }
 101     }
 102 
 103     // Could just be some random pointer within the codeBlob
 104     if (!_cb->code_contains(_pc)) {
 105       return false;
 106     }
 107 
 108     // Entry frame checks
 109     if (is_entry_frame()) {
 110       // an entry frame must have a valid fp.
 111       return fp_safe && is_entry_frame_valid(thread);
 112     }
 113 
 114     intptr_t* sender_sp = NULL;
 115     intptr_t* sender_unextended_sp = NULL;
 116     address   sender_pc = NULL;
 117     intptr_t* saved_fp =  NULL;
 118 
 119     if (is_interpreted_frame()) {
 120       // fp must be safe
 121       if (!fp_safe) {
 122         return false;
 123       }
 124 
 125       sender_pc = (address) this->fp()[return_addr_offset];
 126       // for interpreted frames, the value below is the sender "raw" sp,
 127       // which can be different from the sender unextended sp (the sp seen
 128       // by the sender) because of current frame local variables
 129       sender_sp = (intptr_t*) addr_at(sender_sp_offset);
 130       sender_unextended_sp = (intptr_t*) this->fp()[interpreter_frame_sender_sp_offset];
 131       saved_fp = (intptr_t*) this->fp()[link_offset];
 132 
 133     } else {
 134       // must be some sort of compiled/runtime frame
 135       // fp does not have to be safe (although it could be check for c1?)
 136 
 137       // check for a valid frame_size, otherwise we are unlikely to get a valid sender_pc
 138       if (_cb->frame_size() <= 0) {
 139         return false;
 140       }
 141 
 142       sender_sp = _unextended_sp + _cb->frame_size();
 143       // Is sender_sp safe?
 144       if ((address)sender_sp >= thread->stack_base()) {
 145         return false;
 146       }
 147       // On Intel the return_address is always the word on the stack
 148       sender_pc = (address) *(sender_sp-1);
 149       // Note: frame::sender_sp_offset is only valid for compiled frame
 150       intptr_t** saved_fp_addr = (intptr_t**) (sender_sp - frame::sender_sp_offset);
 151       saved_fp = *saved_fp_addr;
 152 
 153       // Repair the sender sp if this is a method with scalarized value type args
 154       sender_sp = repair_sender_sp(sender_sp, saved_fp_addr);
 155       sender_unextended_sp = sender_sp;
 156     }
 157 
 158     // If the potential sender is the interpreter then we can do some more checking
 159     if (Interpreter::contains(sender_pc)) {
 160 
 161       // ebp is always saved in a recognizable place in any code we generate. However
 162       // only if the sender is interpreted/call_stub (c1 too?) are we certain that the saved ebp
 163       // is really a frame pointer.
 164 
 165       bool saved_fp_safe = ((address)saved_fp < thread->stack_base()) && (saved_fp > sender_sp);
 166 
 167       if (!saved_fp_safe) {
 168         return false;
 169       }
 170 
 171       // construct the potential sender
 172 
 173       frame sender(sender_sp, sender_unextended_sp, saved_fp, sender_pc);
 174 
 175       return sender.is_interpreted_frame_valid(thread);
 176 
 177     }
 178 
 179     // We must always be able to find a recognizable pc
 180     CodeBlob* sender_blob = CodeCache::find_blob_unsafe(sender_pc);
 181     if (sender_pc == NULL ||  sender_blob == NULL) {
 182       return false;
 183     }
 184 
 185     // Could be a zombie method
 186     if (sender_blob->is_zombie() || sender_blob->is_unloaded()) {
 187       return false;
 188     }
 189 
 190     // Could just be some random pointer within the codeBlob
 191     if (!sender_blob->code_contains(sender_pc)) {
 192       return false;
 193     }
 194 
 195     // We should never be able to see an adapter if the current frame is something from code cache
 196     if (sender_blob->is_adapter_blob()) {
 197       return false;
 198     }
 199 
 200     // Could be the call_stub
 201     if (StubRoutines::returns_to_call_stub(sender_pc)) {
 202       bool saved_fp_safe = ((address)saved_fp < thread->stack_base()) && (saved_fp > sender_sp);
 203 
 204       if (!saved_fp_safe) {
 205         return false;
 206       }
 207 
 208       // construct the potential sender
 209 
 210       frame sender(sender_sp, sender_unextended_sp, saved_fp, sender_pc);
 211 
 212       // Validate the JavaCallWrapper an entry frame must have
 213       address jcw = (address)sender.entry_frame_call_wrapper();
 214 
 215       bool jcw_safe = (jcw < thread->stack_base()) && (jcw > (address)sender.fp());
 216 
 217       return jcw_safe;
 218     }
 219 
 220     CompiledMethod* nm = sender_blob->as_compiled_method_or_null();
 221     if (nm != NULL) {
 222         if (nm->is_deopt_mh_entry(sender_pc) || nm->is_deopt_entry(sender_pc) ||
 223             nm->method()->is_method_handle_intrinsic()) {
 224             return false;
 225         }
 226     }
 227 
 228     // If the frame size is 0 something (or less) is bad because every nmethod has a non-zero frame size
 229     // because the return address counts against the callee's frame.
 230 
 231     if (sender_blob->frame_size() <= 0) {
 232       assert(!sender_blob->is_compiled(), "should count return address at least");
 233       return false;
 234     }
 235 
 236     // We should never be able to see anything here except an nmethod. If something in the
 237     // code cache (current frame) is called by an entity within the code cache that entity
 238     // should not be anything but the call stub (already covered), the interpreter (already covered)
 239     // or an nmethod.
 240 
 241     if (!sender_blob->is_compiled()) {
 242         return false;
 243     }
 244 
 245     // Could put some more validation for the potential non-interpreted sender
 246     // frame we'd create by calling sender if I could think of any. Wait for next crash in forte...
 247 
 248     // One idea is seeing if the sender_pc we have is one that we'd expect to call to current cb
 249 
 250     // We've validated the potential sender that would be created
 251     return true;
 252   }
 253 
 254   // Must be native-compiled frame. Since sender will try and use fp to find
 255   // linkages it must be safe
 256 
 257   if (!fp_safe) {
 258     return false;
 259   }
 260 
 261   // Will the pc we fetch be non-zero (which we'll find at the oldest frame)
 262 
 263   if ( (address) this->fp()[return_addr_offset] == NULL) return false;
 264 
 265 
 266   // could try and do some more potential verification of native frame if we could think of some...
 267 
 268   return true;
 269 
 270 }
 271 
 272 
 273 void frame::patch_pc(Thread* thread, address pc) {
 274   address* pc_addr = &(((address*) sp())[-1]);
 275   if (TracePcPatching) {
 276     tty->print_cr("patch_pc at address " INTPTR_FORMAT " [" INTPTR_FORMAT " -> " INTPTR_FORMAT "]",
 277                   p2i(pc_addr), p2i(*pc_addr), p2i(pc));
 278   }
 279   // Either the return address is the original one or we are going to
 280   // patch in the same address that's already there.
 281   assert(_pc == *pc_addr || pc == *pc_addr, "must be");
 282   *pc_addr = pc;
 283   _cb = CodeCache::find_blob(pc);
 284   address original_pc = CompiledMethod::get_deopt_original_pc(this);
 285   if (original_pc != NULL) {
 286     assert(original_pc == _pc, "expected original PC to be stored before patching");
 287     _deopt_state = is_deoptimized;
 288     // leave _pc as is
 289   } else {
 290     _deopt_state = not_deoptimized;
 291     _pc = pc;
 292   }
 293 }
 294 
 295 bool frame::is_interpreted_frame() const  {
 296   return Interpreter::contains(pc());
 297 }
 298 
 299 int frame::frame_size(RegisterMap* map) const {
 300   frame sender = this->sender(map);
 301   return sender.sp() - sp();
 302 }
 303 
 304 intptr_t* frame::entry_frame_argument_at(int offset) const {
 305   // convert offset to index to deal with tsi
 306   int index = (Interpreter::expr_offset_in_bytes(offset)/wordSize);
 307   // Entry frame's arguments are always in relation to unextended_sp()
 308   return &unextended_sp()[index];
 309 }
 310 
 311 // sender_sp
 312 
 313 intptr_t* frame::interpreter_frame_sender_sp() const {
 314   assert(is_interpreted_frame(), "interpreted frame expected");
 315   return (intptr_t*) at(interpreter_frame_sender_sp_offset);
 316 }
 317 
 318 void frame::set_interpreter_frame_sender_sp(intptr_t* sender_sp) {
 319   assert(is_interpreted_frame(), "interpreted frame expected");
 320   ptr_at_put(interpreter_frame_sender_sp_offset, (intptr_t) sender_sp);
 321 }
 322 
 323 
 324 // monitor elements
 325 
 326 BasicObjectLock* frame::interpreter_frame_monitor_begin() const {
 327   return (BasicObjectLock*) addr_at(interpreter_frame_monitor_block_bottom_offset);
 328 }
 329 
 330 BasicObjectLock* frame::interpreter_frame_monitor_end() const {
 331   BasicObjectLock* result = (BasicObjectLock*) *addr_at(interpreter_frame_monitor_block_top_offset);
 332   // make sure the pointer points inside the frame
 333   assert(sp() <= (intptr_t*) result, "monitor end should be above the stack pointer");
 334   assert((intptr_t*) result < fp(),  "monitor end should be strictly below the frame pointer");
 335   return result;
 336 }
 337 
 338 void frame::interpreter_frame_set_monitor_end(BasicObjectLock* value) {
 339   *((BasicObjectLock**)addr_at(interpreter_frame_monitor_block_top_offset)) = value;
 340 }
 341 
 342 // Used by template based interpreter deoptimization
 343 void frame::interpreter_frame_set_last_sp(intptr_t* sp) {
 344     *((intptr_t**)addr_at(interpreter_frame_last_sp_offset)) = sp;
 345 }
 346 
 347 frame frame::sender_for_entry_frame(RegisterMap* map) const {
 348   assert(map != NULL, "map must be set");
 349   // Java frame called from C; skip all C frames and return top C
 350   // frame of that chunk as the sender
 351   JavaFrameAnchor* jfa = entry_frame_call_wrapper()->anchor();
 352   assert(!entry_frame_is_first(), "next Java fp must be non zero");
 353   assert(jfa->last_Java_sp() > sp(), "must be above this frame on stack");
 354   // Since we are walking the stack now this nested anchor is obviously walkable
 355   // even if it wasn't when it was stacked.
 356   if (!jfa->walkable()) {
 357     // Capture _last_Java_pc (if needed) and mark anchor walkable.
 358     jfa->capture_last_Java_pc();
 359   }
 360   map->clear();
 361   assert(map->include_argument_oops(), "should be set by clear");
 362   vmassert(jfa->last_Java_pc() != NULL, "not walkable");
 363   frame fr(jfa->last_Java_sp(), jfa->last_Java_fp(), jfa->last_Java_pc());
 364   return fr;
 365 }
 366 
 367 //------------------------------------------------------------------------------
 368 // frame::verify_deopt_original_pc
 369 //
 370 // Verifies the calculated original PC of a deoptimization PC for the
 371 // given unextended SP.
 372 #ifdef ASSERT
 373 void frame::verify_deopt_original_pc(CompiledMethod* nm, intptr_t* unextended_sp) {
 374   frame fr;
 375 
 376   // This is ugly but it's better than to change {get,set}_original_pc
 377   // to take an SP value as argument.  And it's only a debugging
 378   // method anyway.
 379   fr._unextended_sp = unextended_sp;
 380 
 381   address original_pc = nm->get_original_pc(&fr);
 382   assert(nm->insts_contains_inclusive(original_pc),
 383          "original PC must be in the main code section of the the compiled method (or must be immediately following it)");
 384 }
 385 #endif
 386 
 387 //------------------------------------------------------------------------------
 388 // frame::adjust_unextended_sp
 389 #ifdef ASSERT
 390 void frame::adjust_unextended_sp() {
 391   // On x86, sites calling method handle intrinsics and lambda forms are treated
 392   // as any other call site. Therefore, no special action is needed when we are
 393   // returning to any of these call sites.
 394 
 395   if (_cb != NULL) {
 396     CompiledMethod* sender_cm = _cb->as_compiled_method_or_null();
 397     if (sender_cm != NULL) {
 398       // If the sender PC is a deoptimization point, get the original PC.
 399       if (sender_cm->is_deopt_entry(_pc) ||
 400           sender_cm->is_deopt_mh_entry(_pc)) {
 401         verify_deopt_original_pc(sender_cm, _unextended_sp);
 402       }
 403     }
 404   }
 405 }
 406 #endif
 407 
 408 //------------------------------------------------------------------------------
 409 // frame::update_map_with_saved_link
 410 void frame::update_map_with_saved_link(RegisterMap* map, intptr_t** link_addr) {
 411   // The interpreter and compiler(s) always save EBP/RBP in a known
 412   // location on entry. We must record where that location is
 413   // so this if EBP/RBP was live on callout from c2 we can find
 414   // the saved copy no matter what it called.
 415 
 416   // Since the interpreter always saves EBP/RBP if we record where it is then
 417   // we don't have to always save EBP/RBP on entry and exit to c2 compiled
 418   // code, on entry will be enough.
 419   map->set_location(rbp->as_VMReg(), (address) link_addr);
 420 #ifdef AMD64
 421   // this is weird "H" ought to be at a higher address however the
 422   // oopMaps seems to have the "H" regs at the same address and the
 423   // vanilla register.
 424   // XXXX make this go away
 425   if (true) {
 426     map->set_location(rbp->as_VMReg()->next(), (address) link_addr);
 427   }
 428 #endif // AMD64
 429 }
 430 
 431 
 432 //------------------------------------------------------------------------------
 433 // frame::sender_for_interpreter_frame
 434 frame frame::sender_for_interpreter_frame(RegisterMap* map) const {
 435   // SP is the raw SP from the sender after adapter or interpreter
 436   // extension.
 437   intptr_t* sender_sp = this->sender_sp();
 438 
 439   // This is the sp before any possible extension (adapter/locals).
 440   intptr_t* unextended_sp = interpreter_frame_sender_sp();
 441 
 442 #if COMPILER2_OR_JVMCI
 443   if (map->update_map()) {
 444     update_map_with_saved_link(map, (intptr_t**) addr_at(link_offset));
 445   }
 446 #endif // COMPILER2_OR_JVMCI
 447 
 448   return frame(sender_sp, unextended_sp, link(), sender_pc());
 449 }
 450 
 451 
 452 //------------------------------------------------------------------------------
 453 // frame::sender_for_compiled_frame
 454 frame frame::sender_for_compiled_frame(RegisterMap* map) const {
 455   assert(map != NULL, "map must be set");
 456 
 457   // frame owned by optimizing compiler
 458   assert(_cb->frame_size() >= 0, "must have non-zero frame size");
 459   intptr_t* sender_sp = unextended_sp() + _cb->frame_size();
 460 
 461   // On Intel the return_address is always the word on the stack
 462   address sender_pc = (address) *(sender_sp-1);
 463 
 464   // This is the saved value of EBP which may or may not really be an FP.
 465   // It is only an FP if the sender is an interpreter frame (or C1?).
 466   intptr_t** saved_fp_addr = (intptr_t**) (sender_sp - frame::sender_sp_offset);
 467 
 468   // Repair the sender sp if this is a method with scalarized value type args
 469   sender_sp = repair_sender_sp(sender_sp, saved_fp_addr);
 470 
 471   if (map->update_map()) {
 472     // Tell GC to use argument oopmaps for some runtime stubs that need it.
 473     // For C1, the runtime stub might not have oop maps, so set this flag
 474     // outside of update_register_map.
 475     map->set_include_argument_oops(_cb->caller_must_gc_arguments(map->thread()));
 476     if (_cb->oop_maps() != NULL) {
 477       OopMapSet::update_register_map(this, map);
 478     }
 479 
 480     // Since the prolog does the save and restore of EBP there is no oopmap
 481     // for it so we must fill in its location as if there was an oopmap entry
 482     // since if our caller was compiled code there could be live jvm state in it.
 483     update_map_with_saved_link(map, saved_fp_addr);
 484   }
 485 
 486   assert(sender_sp != sp(), "must have changed");
 487   return frame(sender_sp, sender_sp, *saved_fp_addr, sender_pc);
 488 }
 489 
 490 
 491 //------------------------------------------------------------------------------
 492 // frame::sender
 493 frame frame::sender(RegisterMap* map) const {
 494   // Default is we done have to follow them. The sender_for_xxx will
 495   // update it accordingly
 496   map->set_include_argument_oops(false);
 497 
 498   if (is_entry_frame())       return sender_for_entry_frame(map);
 499   if (is_interpreted_frame()) return sender_for_interpreter_frame(map);
 500   assert(_cb == CodeCache::find_blob(pc()),"Must be the same");
 501 
 502   if (_cb != NULL) {
 503     return sender_for_compiled_frame(map);
 504   }
 505   // Must be native-compiled frame, i.e. the marshaling code for native
 506   // methods that exists in the core system.
 507   return frame(sender_sp(), link(), sender_pc());
 508 }
 509 
 510 bool frame::is_interpreted_frame_valid(JavaThread* thread) const {
 511   assert(is_interpreted_frame(), "Not an interpreted frame");
 512   // These are reasonable sanity checks
 513   if (fp() == 0 || (intptr_t(fp()) & (wordSize-1)) != 0) {
 514     return false;
 515   }
 516   if (sp() == 0 || (intptr_t(sp()) & (wordSize-1)) != 0) {
 517     return false;
 518   }
 519   if (fp() + interpreter_frame_initial_sp_offset < sp()) {
 520     return false;
 521   }
 522   // These are hacks to keep us out of trouble.
 523   // The problem with these is that they mask other problems
 524   if (fp() <= sp()) {        // this attempts to deal with unsigned comparison above
 525     return false;
 526   }
 527 
 528   // do some validation of frame elements
 529   // first the method
 530 
 531   Method* m = *interpreter_frame_method_addr();
 532 
 533   // validate the method we'd find in this potential sender
 534   if (!Method::is_valid_method(m)) return false;
 535 
 536   // stack frames shouldn't be much larger than max_stack elements
 537   // this test requires the use the unextended_sp which is the sp as seen by
 538   // the current frame, and not sp which is the "raw" pc which could point
 539   // further because of local variables of the callee method inserted after
 540   // method arguments
 541   if (fp() - unextended_sp() > 1024 + m->max_stack()*Interpreter::stackElementSize) {
 542     return false;
 543   }
 544 
 545   // validate bci/bcp
 546 
 547   address bcp = interpreter_frame_bcp();
 548   if (m->validate_bci_from_bcp(bcp) < 0) {
 549     return false;
 550   }
 551 
 552   // validate ConstantPoolCache*
 553   ConstantPoolCache* cp = *interpreter_frame_cache_addr();
 554   if (MetaspaceObj::is_valid(cp) == false) return false;
 555 
 556   // validate locals
 557 
 558   address locals =  (address) *interpreter_frame_locals_addr();
 559 
 560   if (locals > thread->stack_base() || locals < (address) fp()) return false;
 561 
 562   // We'd have to be pretty unlucky to be mislead at this point
 563   return true;
 564 }
 565 
 566 BasicType frame::interpreter_frame_result(oop* oop_result, jvalue* value_result) {
 567   assert(is_interpreted_frame(), "interpreted frame expected");
 568   Method* method = interpreter_frame_method();
 569   BasicType type = method->result_type();
 570 
 571   intptr_t* tos_addr;
 572   if (method->is_native()) {
 573     // Prior to calling into the runtime to report the method_exit the possible
 574     // return value is pushed to the native stack. If the result is a jfloat/jdouble
 575     // then ST0 is saved before EAX/EDX. See the note in generate_native_result
 576     tos_addr = (intptr_t*)sp();
 577     if (type == T_FLOAT || type == T_DOUBLE) {
 578     // QQQ seems like this code is equivalent on the two platforms
 579 #ifdef AMD64
 580       // This is times two because we do a push(ltos) after pushing XMM0
 581       // and that takes two interpreter stack slots.
 582       tos_addr += 2 * Interpreter::stackElementWords;
 583 #else
 584       tos_addr += 2;
 585 #endif // AMD64
 586     }
 587   } else {
 588     tos_addr = (intptr_t*)interpreter_frame_tos_address();
 589   }
 590 
 591   switch (type) {
 592     case T_OBJECT  :
 593     case T_VALUETYPE:
 594     case T_ARRAY   : {
 595       oop obj;
 596       if (method->is_native()) {
 597         obj = cast_to_oop(at(interpreter_frame_oop_temp_offset));
 598       } else {
 599         oop* obj_p = (oop*)tos_addr;
 600         obj = (obj_p == NULL) ? (oop)NULL : *obj_p;
 601       }
 602       assert(obj == NULL || Universe::heap()->is_in(obj), "sanity check");
 603       *oop_result = obj;
 604       break;
 605     }
 606     case T_BOOLEAN : value_result->z = *(jboolean*)tos_addr; break;
 607     case T_BYTE    : value_result->b = *(jbyte*)tos_addr; break;
 608     case T_CHAR    : value_result->c = *(jchar*)tos_addr; break;
 609     case T_SHORT   : value_result->s = *(jshort*)tos_addr; break;
 610     case T_INT     : value_result->i = *(jint*)tos_addr; break;
 611     case T_LONG    : value_result->j = *(jlong*)tos_addr; break;
 612     case T_FLOAT   : {
 613 #ifdef AMD64
 614         value_result->f = *(jfloat*)tos_addr;
 615 #else
 616       if (method->is_native()) {
 617         jdouble d = *(jdouble*)tos_addr;  // Result was in ST0 so need to convert to jfloat
 618         value_result->f = (jfloat)d;
 619       } else {
 620         value_result->f = *(jfloat*)tos_addr;
 621       }
 622 #endif // AMD64
 623       break;
 624     }
 625     case T_DOUBLE  : value_result->d = *(jdouble*)tos_addr; break;
 626     case T_VOID    : /* Nothing to do */ break;
 627     default        : ShouldNotReachHere();
 628   }
 629 
 630   return type;
 631 }
 632 
 633 
 634 intptr_t* frame::interpreter_frame_tos_at(jint offset) const {
 635   int index = (Interpreter::expr_offset_in_bytes(offset)/wordSize);
 636   return &interpreter_frame_tos_address()[index];
 637 }
 638 
 639 #ifndef PRODUCT
 640 
 641 #define DESCRIBE_FP_OFFSET(name) \
 642   values.describe(frame_no, fp() + frame::name##_offset, #name)
 643 
 644 void frame::describe_pd(FrameValues& values, int frame_no) {
 645   if (is_interpreted_frame()) {
 646     DESCRIBE_FP_OFFSET(interpreter_frame_sender_sp);
 647     DESCRIBE_FP_OFFSET(interpreter_frame_last_sp);
 648     DESCRIBE_FP_OFFSET(interpreter_frame_method);
 649     DESCRIBE_FP_OFFSET(interpreter_frame_mirror);
 650     DESCRIBE_FP_OFFSET(interpreter_frame_mdp);
 651     DESCRIBE_FP_OFFSET(interpreter_frame_cache);
 652     DESCRIBE_FP_OFFSET(interpreter_frame_locals);
 653     DESCRIBE_FP_OFFSET(interpreter_frame_bcp);
 654     DESCRIBE_FP_OFFSET(interpreter_frame_initial_sp);
 655 #ifdef AMD64
 656   } else if (is_entry_frame()) {
 657     // This could be more descriptive if we use the enum in
 658     // stubGenerator to map to real names but it's most important to
 659     // claim these frame slots so the error checking works.
 660     for (int i = 0; i < entry_frame_after_call_words; i++) {
 661       values.describe(frame_no, fp() - i, err_msg("call_stub word fp - %d", i));
 662     }
 663 #endif // AMD64
 664   }
 665 }
 666 #endif // !PRODUCT
 667 
 668 intptr_t *frame::initial_deoptimization_info() {
 669   // used to reset the saved FP
 670   return fp();
 671 }
 672 
 673 intptr_t* frame::real_fp() const {
 674   if (_cb != NULL) {
 675     // use the frame size if valid
 676     int size = _cb->frame_size();
 677     if (size > 0) {
 678       return unextended_sp() + size;
 679     }
 680   }
 681   // else rely on fp()
 682   assert(! is_compiled_frame(), "unknown compiled frame size");
 683   return fp();
 684 }
 685 
 686 #ifndef PRODUCT
 687 // This is a generic constructor which is only used by pns() in debug.cpp.
 688 frame::frame(void* sp, void* fp, void* pc) {
 689   init((intptr_t*)sp, (intptr_t*)fp, (address)pc);
 690 }
 691 
 692 void frame::pd_ps() {}
 693 #endif
 694 
 695 // Check for a method with scalarized value type arguments that needs
 696 // a stack repair and return the repaired sender stack pointer.
 697 intptr_t* frame::repair_sender_sp(intptr_t* sender_sp, intptr_t** saved_fp_addr) const {
 698   CompiledMethod* cm = _cb->as_compiled_method_or_null();
 699   if (cm != NULL && cm->needs_stack_repair()) {
 700     // The stack increment resides just below the saved rbp on the stack
 701     // and does not account for the return address.
 702     intptr_t* sp_inc_addr = (intptr_t*) (saved_fp_addr - 1);
 703     int sp_inc = (*sp_inc_addr) / wordSize;
 704     int real_frame_size = sp_inc;
 705     if (!cm->is_compiled_by_c1()) {
 706       // Add size of return address (C1 already includes the RA size)
 707       real_frame_size += 1;
 708     }
 709     assert(real_frame_size >= _cb->frame_size(), "invalid frame size");
 710     sender_sp = unextended_sp() + real_frame_size;
 711   }
 712   return sender_sp;
 713 }
 714 
 715 void JavaFrameAnchor::make_walkable(JavaThread* thread) {
 716   // last frame set?
 717   if (last_Java_sp() == NULL) return;
 718   // already walkable?
 719   if (walkable()) return;
 720   vmassert(Thread::current() == (Thread*)thread, "not current thread");
 721   vmassert(last_Java_sp() != NULL, "not called from Java code?");
 722   vmassert(last_Java_pc() == NULL, "already walkable");
 723   capture_last_Java_pc();
 724   vmassert(walkable(), "something went wrong");
 725 }
 726 
 727 void JavaFrameAnchor::capture_last_Java_pc() {
 728   vmassert(_last_Java_sp != NULL, "no last frame set");
 729   vmassert(_last_Java_pc == NULL, "already walkable");
 730   _last_Java_pc = (address)_last_Java_sp[-1];
 731 }