1 /*
   2  * Copyright (c) 2008, 2016, 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 "runtime/frame.inline.hpp"
  32 #include "runtime/handles.inline.hpp"
  33 #include "runtime/javaCalls.hpp"
  34 #include "runtime/monitorChunk.hpp"
  35 #include "runtime/signature.hpp"
  36 #include "runtime/stubCodeGenerator.hpp"
  37 #include "runtime/stubRoutines.hpp"
  38 #include "vmreg_arm.inline.hpp"
  39 #ifdef COMPILER1
  40 #include "c1/c1_Runtime1.hpp"
  41 #include "runtime/vframeArray.hpp"
  42 #endif
  43 #include "prims/methodHandles.hpp"
  44 
  45 #ifdef ASSERT
  46 void RegisterMap::check_location_valid() {
  47 }
  48 #endif
  49 
  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   static size_t stack_guard_size = os::uses_stack_guard_pages() ?
  59     (JavaThread::stack_red_zone_size() + JavaThread::stack_yellow_zone_size()) : 0;
  60   size_t usable_stack_size = thread->stack_size() - stack_guard_size;
  61 
  62   // sp must be within the usable part of the stack (not in guards)
  63   bool sp_safe = (sp != NULL &&
  64                  (sp <= thread->stack_base()) &&
  65                  (sp >= thread->stack_base() - usable_stack_size));
  66 
  67   if (!sp_safe) {
  68     return false;
  69   }
  70 
  71   bool unextended_sp_safe = (unextended_sp != NULL &&
  72                              (unextended_sp <= thread->stack_base()) &&
  73                              (unextended_sp >= sp));
  74   if (!unextended_sp_safe) {
  75     return false;
  76   }
  77 
  78   // We know sp/unextended_sp are safe. Only fp is questionable here.
  79 
  80   bool fp_safe = (fp != NULL &&
  81                   (fp <= thread->stack_base()) &&
  82                   fp >= sp);
  83 
  84   if (_cb != NULL ) {
  85 
  86     // First check if frame is complete and tester is reliable
  87     // Unfortunately we can only check frame complete for runtime stubs and nmethod
  88     // other generic buffer blobs are more problematic so we just assume they are
  89     // ok. adapter blobs never have a frame complete and are never ok.
  90 
  91     if (!_cb->is_frame_complete_at(_pc)) {
  92       if (_cb->is_compiled() || _cb->is_adapter_blob() || _cb->is_runtime_stub()) {
  93         return false;
  94       }
  95     }
  96 
  97     // Could just be some random pointer within the codeBlob
  98     if (!_cb->code_contains(_pc)) {
  99       return false;
 100     }
 101 
 102     // Entry frame checks
 103     if (is_entry_frame()) {
 104       // an entry frame must have a valid fp.
 105       return fp_safe && is_entry_frame_valid(thread);
 106     }
 107 
 108     intptr_t* sender_sp = NULL;
 109     address   sender_pc = NULL;
 110 
 111     if (is_interpreted_frame()) {
 112       // fp must be safe
 113       if (!fp_safe) {
 114         return false;
 115       }
 116 
 117       sender_pc = (address) this->fp()[return_addr_offset];
 118       sender_sp = (intptr_t*) addr_at(sender_sp_offset);
 119 
 120     } else {
 121       // must be some sort of compiled/runtime frame
 122       // fp does not have to be safe (although it could be check for c1?)
 123 
 124       sender_sp = _unextended_sp + _cb->frame_size();
 125       // With our calling conventions, the return_address should
 126       // end up being the word on the stack
 127       sender_pc = (address) *(sender_sp - sender_sp_offset + return_addr_offset);
 128     }
 129 
 130     // We must always be able to find a recognizable pc
 131     CodeBlob* sender_blob = CodeCache::find_blob_unsafe(sender_pc);
 132     if (sender_pc == NULL || sender_blob == NULL) {
 133       return false;
 134     }
 135 
 136 
 137     // If the potential sender is the interpreter then we can do some more checking
 138     if (Interpreter::contains(sender_pc)) {
 139 
 140       // FP is always saved in a recognizable place in any code we generate. However
 141       // only if the sender is interpreted/call_stub (c1 too?) are we certain that the saved FP
 142       // is really a frame pointer.
 143 
 144       intptr_t *saved_fp = (intptr_t*)*(sender_sp - frame::sender_sp_offset + link_offset);
 145       bool saved_fp_safe = ((address)saved_fp <= thread->stack_base()) && (saved_fp > sender_sp);
 146 
 147       if (!saved_fp_safe) {
 148         return false;
 149       }
 150 
 151       // construct the potential sender
 152 
 153       frame sender(sender_sp, saved_fp, sender_pc);
 154 
 155       return sender.is_interpreted_frame_valid(thread);
 156     }
 157 
 158     if (sender_blob->is_zombie() || sender_blob->is_unloaded()) {
 159       return false;
 160     }
 161 
 162     // Could just be some random pointer within the codeBlob
 163     if (!sender_blob->code_contains(sender_pc)) {
 164       return false;
 165     }
 166 
 167     // We should never be able to see an adapter if the current frame is something from code cache
 168     if (sender_blob->is_adapter_blob()) {
 169       return false;
 170     }
 171 
 172     // Could be the call_stub
 173     if (StubRoutines::returns_to_call_stub(sender_pc)) {
 174       intptr_t *saved_fp = (intptr_t*)*(sender_sp - frame::sender_sp_offset + link_offset);
 175       bool saved_fp_safe = ((address)saved_fp <= thread->stack_base()) && (saved_fp >= sender_sp);
 176 
 177       if (!saved_fp_safe) {
 178         return false;
 179       }
 180 
 181       // construct the potential sender
 182 
 183       frame sender(sender_sp, saved_fp, sender_pc);
 184       return sender.is_entry_frame_valid(thread);
 185     }
 186 
 187     // If the frame size is 0 something (or less) is bad because every nmethod has a non-zero frame size
 188     // because the return address counts against the callee's frame.
 189 
 190     if (sender_blob->frame_size() <= 0) {
 191       assert(!sender_blob->is_compiled(), "should count return address at least");
 192       return false;
 193     }
 194 
 195     // We should never be able to see anything here except an nmethod. If something in the
 196     // code cache (current frame) is called by an entity within the code cache that entity
 197     // should not be anything but the call stub (already covered), the interpreter (already covered)
 198     // or an nmethod.
 199 
 200     if (!sender_blob->is_compiled()) {
 201       return false;
 202     }
 203 
 204     // Could put some more validation for the potential non-interpreted sender
 205     // frame we'd create by calling sender if I could think of any. Wait for next crash in forte...
 206 
 207     // One idea is seeing if the sender_pc we have is one that we'd expect to call to current cb
 208 
 209     // We've validated the potential sender that would be created
 210     return true;
 211   }
 212 
 213   // Must be native-compiled frame. Since sender will try and use fp to find
 214   // linkages it must be safe
 215 
 216   if (!fp_safe) {
 217     return false;
 218   }
 219 
 220   // Will the pc we fetch be non-zero (which we'll find at the oldest frame)
 221 
 222   if ((address) this->fp()[return_addr_offset] == NULL) return false;
 223 
 224 
 225   // could try and do some more potential verification of native frame if we could think of some...
 226 
 227   return true;
 228 }
 229 
 230 
 231 void frame::patch_pc(Thread* thread, address pc) {
 232   address* pc_addr = &((address *)sp())[-sender_sp_offset+return_addr_offset];
 233   if (TracePcPatching) {
 234     tty->print_cr("patch_pc at address" INTPTR_FORMAT " [" INTPTR_FORMAT " -> " INTPTR_FORMAT "] ",
 235                   p2i(pc_addr), p2i(*pc_addr), p2i(pc));
 236   }
 237   *pc_addr = pc;
 238   _cb = CodeCache::find_blob(pc);
 239   address original_pc = CompiledMethod::get_deopt_original_pc(this);
 240   if (original_pc != NULL) {
 241     assert(original_pc == _pc, "expected original PC to be stored before patching");
 242     _deopt_state = is_deoptimized;
 243     // leave _pc as is
 244   } else {
 245     _deopt_state = not_deoptimized;
 246     _pc = pc;
 247   }
 248 }
 249 
 250 bool frame::is_interpreted_frame() const  {
 251   return Interpreter::contains(pc());
 252 }
 253 
 254 int frame::frame_size(RegisterMap* map) const {
 255   frame sender = this->sender(map);
 256   return sender.sp() - sp();
 257 }
 258 
 259 intptr_t* frame::entry_frame_argument_at(int offset) const {
 260   assert(is_entry_frame(), "entry frame expected");
 261   // convert offset to index to deal with tsi
 262   int index = (Interpreter::expr_offset_in_bytes(offset)/wordSize);
 263   // Entry frame's arguments are always in relation to unextended_sp()
 264   return &unextended_sp()[index];
 265 }
 266 
 267 // sender_sp
 268 intptr_t* frame::interpreter_frame_sender_sp() const {
 269   assert(is_interpreted_frame(), "interpreted frame expected");
 270   return (intptr_t*) at(interpreter_frame_sender_sp_offset);
 271 }
 272 
 273 void frame::set_interpreter_frame_sender_sp(intptr_t* sender_sp) {
 274   assert(is_interpreted_frame(), "interpreted frame expected");
 275   ptr_at_put(interpreter_frame_sender_sp_offset, (intptr_t) sender_sp);
 276 }
 277 
 278 
 279 // monitor elements
 280 
 281 BasicObjectLock* frame::interpreter_frame_monitor_begin() const {
 282   return (BasicObjectLock*) addr_at(interpreter_frame_monitor_block_bottom_offset);
 283 }
 284 
 285 BasicObjectLock* frame::interpreter_frame_monitor_end() const {
 286   BasicObjectLock* result = (BasicObjectLock*) *addr_at(interpreter_frame_monitor_block_top_offset);
 287   // make sure the pointer points inside the frame
 288   assert((intptr_t) fp() >  (intptr_t) result, "result must <  than frame pointer");
 289   assert((intptr_t) sp() <= (intptr_t) result, "result must >= than stack pointer");
 290   return result;
 291 }
 292 
 293 void frame::interpreter_frame_set_monitor_end(BasicObjectLock* value) {
 294   *((BasicObjectLock**)addr_at(interpreter_frame_monitor_block_top_offset)) = value;
 295 }
 296 
 297 #ifdef AARCH64
 298 
 299 // Used by template based interpreter deoptimization
 300 void frame::interpreter_frame_set_stack_top(intptr_t* stack_top) {
 301   *((intptr_t**)addr_at(interpreter_frame_stack_top_offset)) = stack_top;
 302 }
 303 
 304 // Used by template based interpreter deoptimization
 305 void frame::interpreter_frame_set_extended_sp(intptr_t* sp) {
 306   *((intptr_t**)addr_at(interpreter_frame_extended_sp_offset)) = sp;
 307 }
 308 
 309 #else
 310 
 311 // Used by template based interpreter deoptimization
 312 void frame::interpreter_frame_set_last_sp(intptr_t* sp) {
 313     *((intptr_t**)addr_at(interpreter_frame_last_sp_offset)) = sp;
 314 }
 315 
 316 #endif // AARCH64
 317 
 318 frame frame::sender_for_entry_frame(RegisterMap* map) const {
 319   assert(map != NULL, "map must be set");
 320   // Java frame called from C; skip all C frames and return top C
 321   // frame of that chunk as the sender
 322   JavaFrameAnchor* jfa = entry_frame_call_wrapper()->anchor();
 323   assert(!entry_frame_is_first(), "next Java fp must be non zero");
 324   assert(jfa->last_Java_sp() > sp(), "must be above this frame on stack");
 325   map->clear();
 326   assert(map->include_argument_oops(), "should be set by clear");
 327 #ifdef AARCH64
 328   assert (jfa->last_Java_pc() != NULL, "pc should be stored");
 329   frame fr(jfa->last_Java_sp(), jfa->last_Java_fp(), jfa->last_Java_pc());
 330   return fr;
 331 #else
 332   if (jfa->last_Java_pc() != NULL) {
 333     frame fr(jfa->last_Java_sp(), jfa->last_Java_fp(), jfa->last_Java_pc());
 334     return fr;
 335   }
 336   frame fr(jfa->last_Java_sp(), jfa->last_Java_fp());
 337   return fr;
 338 #endif // AARCH64
 339 }
 340 
 341 //------------------------------------------------------------------------------
 342 // frame::verify_deopt_original_pc
 343 //
 344 // Verifies the calculated original PC of a deoptimization PC for the
 345 // given unextended SP.  The unextended SP might also be the saved SP
 346 // for MethodHandle call sites.
 347 #ifdef ASSERT
 348 void frame::verify_deopt_original_pc(CompiledMethod* nm, intptr_t* unextended_sp, bool is_method_handle_return) {
 349   frame fr;
 350 
 351   // This is ugly but it's better than to change {get,set}_original_pc
 352   // to take an SP value as argument.  And it's only a debugging
 353   // method anyway.
 354   fr._unextended_sp = unextended_sp;
 355 
 356   address original_pc = nm->get_original_pc(&fr);
 357   assert(nm->insts_contains(original_pc), "original PC must be in nmethod");
 358   assert(nm->is_method_handle_return(original_pc) == is_method_handle_return, "must be");
 359 }
 360 #endif
 361 
 362 //------------------------------------------------------------------------------
 363 // frame::adjust_unextended_sp
 364 void frame::adjust_unextended_sp() {
 365   // same as on x86
 366 
 367   // If we are returning to a compiled MethodHandle call site, the
 368   // saved_fp will in fact be a saved value of the unextended SP.  The
 369   // simplest way to tell whether we are returning to such a call site
 370   // is as follows:
 371 
 372   CompiledMethod* sender_cm = (_cb == NULL) ? NULL : _cb->as_compiled_method_or_null();
 373   if (sender_cm != NULL) {
 374     // If the sender PC is a deoptimization point, get the original
 375     // PC.  For MethodHandle call site the unextended_sp is stored in
 376     // saved_fp.
 377     if (sender_cm->is_deopt_mh_entry(_pc)) {
 378       DEBUG_ONLY(verify_deopt_mh_original_pc(sender_cm, _fp));
 379       _unextended_sp = _fp;
 380     }
 381     else if (sender_cm->is_deopt_entry(_pc)) {
 382       DEBUG_ONLY(verify_deopt_original_pc(sender_cm, _unextended_sp));
 383     }
 384     else if (sender_cm->is_method_handle_return(_pc)) {
 385       _unextended_sp = _fp;
 386     }
 387   }
 388 }
 389 
 390 //------------------------------------------------------------------------------
 391 // frame::update_map_with_saved_link
 392 void frame::update_map_with_saved_link(RegisterMap* map, intptr_t** link_addr) {
 393   // see x86 for comments
 394   map->set_location(FP->as_VMReg(), (address) link_addr);
 395 #ifdef AARCH64
 396   // also adjust a high part of register
 397   map->set_location(FP->as_VMReg()->next(), (address) link_addr);
 398 #endif // AARCH64
 399 }
 400 
 401 frame frame::sender_for_interpreter_frame(RegisterMap* map) const {
 402   // SP is the raw SP from the sender after adapter or interpreter
 403   // extension.
 404   intptr_t* sender_sp = this->sender_sp();
 405 
 406   // This is the sp before any possible extension (adapter/locals).
 407   intptr_t* unextended_sp = interpreter_frame_sender_sp();
 408 
 409 #ifdef COMPILER2
 410   if (map->update_map()) {
 411     update_map_with_saved_link(map, (intptr_t**) addr_at(link_offset));
 412   }
 413 #endif // COMPILER2
 414 
 415   return frame(sender_sp, unextended_sp, link(), sender_pc());
 416 }
 417 
 418 frame frame::sender_for_compiled_frame(RegisterMap* map) const {
 419   assert(map != NULL, "map must be set");
 420 
 421   // frame owned by optimizing compiler
 422   assert(_cb->frame_size() >= 0, "must have non-zero frame size");
 423   intptr_t* sender_sp = unextended_sp() + _cb->frame_size();
 424   intptr_t* unextended_sp = sender_sp;
 425 
 426   address sender_pc = (address) *(sender_sp - sender_sp_offset + return_addr_offset);
 427 
 428   // This is the saved value of FP which may or may not really be an FP.
 429   // It is only an FP if the sender is an interpreter frame (or C1?).
 430   intptr_t** saved_fp_addr = (intptr_t**) (sender_sp - sender_sp_offset + link_offset);
 431 
 432   if (map->update_map()) {
 433     // Tell GC to use argument oopmaps for some runtime stubs that need it.
 434     // For C1, the runtime stub might not have oop maps, so set this flag
 435     // outside of update_register_map.
 436     map->set_include_argument_oops(_cb->caller_must_gc_arguments(map->thread()));
 437     if (_cb->oop_maps() != NULL) {
 438       OopMapSet::update_register_map(this, map);
 439     }
 440 
 441     // Since the prolog does the save and restore of FP there is no oopmap
 442     // for it so we must fill in its location as if there was an oopmap entry
 443     // since if our caller was compiled code there could be live jvm state in it.
 444     update_map_with_saved_link(map, saved_fp_addr);
 445   }
 446 
 447   assert(sender_sp != sp(), "must have changed");
 448   return frame(sender_sp, unextended_sp, *saved_fp_addr, sender_pc);
 449 }
 450 
 451 frame frame::sender(RegisterMap* map) const {
 452   // Default is we done have to follow them. The sender_for_xxx will
 453   // update it accordingly
 454   map->set_include_argument_oops(false);
 455 
 456   if (is_entry_frame())       return sender_for_entry_frame(map);
 457   if (is_interpreted_frame()) return sender_for_interpreter_frame(map);
 458   assert(_cb == CodeCache::find_blob(pc()),"Must be the same");
 459 
 460   if (_cb != NULL) {
 461     return sender_for_compiled_frame(map);
 462   }
 463 
 464   assert(false, "should not be called for a C frame");
 465   return frame();
 466 }
 467 
 468 bool frame::is_interpreted_frame_valid(JavaThread* thread) const {
 469   assert(is_interpreted_frame(), "Not an interpreted frame");
 470   // These are reasonable sanity checks
 471   if (fp() == 0 || (intptr_t(fp()) & (wordSize-1)) != 0) {
 472     return false;
 473   }
 474   if (sp() == 0 || (intptr_t(sp()) & (wordSize-1)) != 0) {
 475     return false;
 476   }
 477   if (fp() + interpreter_frame_initial_sp_offset < sp()) {
 478     return false;
 479   }
 480   // These are hacks to keep us out of trouble.
 481   // The problem with these is that they mask other problems
 482   if (fp() <= sp()) {        // this attempts to deal with unsigned comparison above
 483     return false;
 484   }
 485   // do some validation of frame elements
 486 
 487   // first the method
 488 
 489   Method* m = *interpreter_frame_method_addr();
 490 
 491   // validate the method we'd find in this potential sender
 492   if (!m->is_valid_method()) return false;
 493 
 494   // stack frames shouldn't be much larger than max_stack elements
 495 
 496   if (fp() - sp() > 1024 + m->max_stack()*Interpreter::stackElementSize) {
 497     return false;
 498   }
 499 
 500   // validate bci/bcp
 501 
 502   address bcp = interpreter_frame_bcp();
 503   if (m->validate_bci_from_bcp(bcp) < 0) {
 504     return false;
 505   }
 506 
 507   // validate ConstantPoolCache*
 508   ConstantPoolCache* cp = *interpreter_frame_cache_addr();
 509   if (cp == NULL || !cp->is_metaspace_object()) return false;
 510 
 511   // validate locals
 512 
 513   address locals =  (address) *interpreter_frame_locals_addr();
 514 
 515   if (locals > thread->stack_base() || locals < (address) fp()) return false;
 516 
 517   // We'd have to be pretty unlucky to be mislead at this point
 518 
 519   return true;
 520 }
 521 
 522 BasicType frame::interpreter_frame_result(oop* oop_result, jvalue* value_result) {
 523   assert(is_interpreted_frame(), "interpreted frame expected");
 524   Method* method = interpreter_frame_method();
 525   BasicType type = method->result_type();
 526 
 527   intptr_t* res_addr;
 528   if (method->is_native()) {
 529     // Prior to calling into the runtime to report the method_exit both of
 530     // the possible return value registers are saved.
 531 #ifdef AARCH64
 532     // Return value registers are saved into the frame
 533     if (type == T_FLOAT || type == T_DOUBLE) {
 534       res_addr = addr_at(interpreter_frame_fp_saved_result_offset);
 535     } else {
 536       res_addr = addr_at(interpreter_frame_gp_saved_result_offset);
 537     }
 538 #else
 539     // Return value registers are pushed to the native stack
 540     res_addr = (intptr_t*)sp();
 541 #ifdef __ABI_HARD__
 542     // FP result is pushed onto a stack along with integer result registers
 543     if (type == T_FLOAT || type == T_DOUBLE) {
 544       res_addr += 2;
 545     }
 546 #endif // __ABI_HARD__
 547 #endif // AARCH64
 548   } else {
 549     res_addr = (intptr_t*)interpreter_frame_tos_address();
 550   }
 551 
 552   switch (type) {
 553     case T_OBJECT  :
 554     case T_ARRAY   : {
 555       oop obj;
 556       if (method->is_native()) {
 557         obj = cast_to_oop(at(interpreter_frame_oop_temp_offset));
 558       } else {
 559         obj = *(oop*)res_addr;
 560       }
 561       assert(obj == NULL || Universe::heap()->is_in(obj), "sanity check");
 562       *oop_result = obj;
 563       break;
 564     }
 565     case T_BOOLEAN : value_result->z = *(jboolean*)res_addr; break;
 566     case T_BYTE    : value_result->b = *(jbyte*)res_addr; break;
 567     case T_CHAR    : value_result->c = *(jchar*)res_addr; break;
 568     case T_SHORT   : value_result->s = *(jshort*)res_addr; break;
 569     case T_INT     : value_result->i = *(jint*)res_addr; break;
 570     case T_LONG    : value_result->j = *(jlong*)res_addr; break;
 571     case T_FLOAT   : value_result->f = *(jfloat*)res_addr; break;
 572     case T_DOUBLE  : value_result->d = *(jdouble*)res_addr; break;
 573     case T_VOID    : /* Nothing to do */ break;
 574     default        : ShouldNotReachHere();
 575   }
 576 
 577   return type;
 578 }
 579 
 580 
 581 intptr_t* frame::interpreter_frame_tos_at(jint offset) const {
 582   int index = (Interpreter::expr_offset_in_bytes(offset)/wordSize);
 583   return &interpreter_frame_tos_address()[index];
 584 }
 585 
 586 #ifndef PRODUCT
 587 
 588 #define DESCRIBE_FP_OFFSET(name) \
 589   values.describe(frame_no, fp() + frame::name##_offset, #name)
 590 
 591 void frame::describe_pd(FrameValues& values, int frame_no) {
 592   if (is_interpreted_frame()) {
 593     DESCRIBE_FP_OFFSET(interpreter_frame_sender_sp);
 594 #ifdef AARCH64
 595     DESCRIBE_FP_OFFSET(interpreter_frame_stack_top);
 596     DESCRIBE_FP_OFFSET(interpreter_frame_extended_sp);
 597 #else
 598     DESCRIBE_FP_OFFSET(interpreter_frame_last_sp);
 599 #endif // AARCH64
 600     DESCRIBE_FP_OFFSET(interpreter_frame_method);
 601     DESCRIBE_FP_OFFSET(interpreter_frame_mdp);
 602     DESCRIBE_FP_OFFSET(interpreter_frame_cache);
 603     DESCRIBE_FP_OFFSET(interpreter_frame_locals);
 604     DESCRIBE_FP_OFFSET(interpreter_frame_bcp);
 605     DESCRIBE_FP_OFFSET(interpreter_frame_initial_sp);
 606   }
 607 }
 608 
 609 // This is a generic constructor which is only used by pns() in debug.cpp.
 610 frame::frame(void* sp, void* fp, void* pc) {
 611   init((intptr_t*)sp, (intptr_t*)fp, (address)pc);
 612 }
 613 #endif
 614 
 615 intptr_t *frame::initial_deoptimization_info() {
 616   // used to reset the saved FP
 617   return fp();
 618 }
 619 
 620 intptr_t* frame::real_fp() const {
 621 #ifndef AARCH64
 622   if (is_entry_frame()) {
 623     // Work-around: FP (currently) does not conform to the ABI for entry
 624     // frames (see generate_call_stub). Might be worth fixing as another CR.
 625     // Following code assumes (and asserts) this has not yet been fixed.
 626     assert(frame::entry_frame_call_wrapper_offset == 0, "adjust this code");
 627     intptr_t* new_fp = fp();
 628     new_fp += 5; // saved R0,R1,R2,R4,R10
 629 #ifndef __SOFTFP__
 630     new_fp += 8*2; // saved D8..D15
 631 #endif
 632     return new_fp;
 633   }
 634 #endif // !AARCH64
 635   if (_cb != NULL) {
 636     // use the frame size if valid
 637     int size = _cb->frame_size();
 638     if (size > 0) {
 639       return unextended_sp() + size;
 640     }
 641   }
 642   // else rely on fp()
 643   assert(! is_compiled_frame(), "unknown compiled frame size");
 644   return fp();
 645 }