1 /*
   2  * Copyright (c) 1997, 2018, 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       sender_unextended_sp = sender_sp;
 148       // On Intel the return_address is always the word on the stack
 149       sender_pc = (address) *(sender_sp-1);
 150       // Note: frame::sender_sp_offset is only valid for compiled frame
 151       saved_fp = (intptr_t*) *(sender_sp - frame::sender_sp_offset);
 152     }
 153 
 154 
 155     // If the potential sender is the interpreter then we can do some more checking
 156     if (Interpreter::contains(sender_pc)) {
 157 
 158       // ebp is always saved in a recognizable place in any code we generate. However
 159       // only if the sender is interpreted/call_stub (c1 too?) are we certain that the saved ebp
 160       // is really a frame pointer.
 161 
 162       bool saved_fp_safe = ((address)saved_fp < thread->stack_base()) && (saved_fp > sender_sp);
 163 
 164       if (!saved_fp_safe) {
 165         return false;
 166       }
 167 
 168       // construct the potential sender
 169 
 170       frame sender(sender_sp, sender_unextended_sp, saved_fp, sender_pc);
 171 
 172       return sender.is_interpreted_frame_valid(thread);
 173 
 174     }
 175 
 176     // We must always be able to find a recognizable pc
 177     CodeBlob* sender_blob = CodeCache::find_blob_unsafe(sender_pc);
 178     if (sender_pc == NULL ||  sender_blob == NULL) {
 179       return false;
 180     }
 181 
 182     // Could be a zombie method
 183     if (sender_blob->is_zombie() || sender_blob->is_unloaded()) {
 184       return false;
 185     }
 186 
 187     // Could just be some random pointer within the codeBlob
 188     if (!sender_blob->code_contains(sender_pc)) {
 189       return false;
 190     }
 191 
 192     // We should never be able to see an adapter if the current frame is something from code cache
 193     if (sender_blob->is_adapter_blob()) {
 194       return false;
 195     }
 196 
 197     // Could be the call_stub
 198     if (StubRoutines::returns_to_call_stub(sender_pc)) {
 199       bool saved_fp_safe = ((address)saved_fp < thread->stack_base()) && (saved_fp > sender_sp);
 200 
 201       if (!saved_fp_safe) {
 202         return false;
 203       }
 204 
 205       // construct the potential sender
 206 
 207       frame sender(sender_sp, sender_unextended_sp, saved_fp, sender_pc);
 208 
 209       // Validate the JavaCallWrapper an entry frame must have
 210       address jcw = (address)sender.entry_frame_call_wrapper();
 211 
 212       bool jcw_safe = (jcw < thread->stack_base()) && (jcw > (address)sender.fp());
 213 
 214       return jcw_safe;
 215     }
 216 
 217     CompiledMethod* nm = sender_blob->as_compiled_method_or_null();
 218     if (nm != NULL) {
 219         if (nm->is_deopt_mh_entry(sender_pc) || nm->is_deopt_entry(sender_pc) ||
 220             nm->method()->is_method_handle_intrinsic()) {
 221             return false;
 222         }
 223     }
 224 
 225     // If the frame size is 0 something (or less) is bad because every nmethod has a non-zero frame size
 226     // because the return address counts against the callee's frame.
 227 
 228     if (sender_blob->frame_size() <= 0) {
 229       assert(!sender_blob->is_compiled(), "should count return address at least");
 230       return false;
 231     }
 232 
 233     // We should never be able to see anything here except an nmethod. If something in the
 234     // code cache (current frame) is called by an entity within the code cache that entity
 235     // should not be anything but the call stub (already covered), the interpreter (already covered)
 236     // or an nmethod.
 237 
 238     if (!sender_blob->is_compiled()) {
 239         return false;
 240     }
 241 
 242     // Could put some more validation for the potential non-interpreted sender
 243     // frame we'd create by calling sender if I could think of any. Wait for next crash in forte...
 244 
 245     // One idea is seeing if the sender_pc we have is one that we'd expect to call to current cb
 246 
 247     // We've validated the potential sender that would be created
 248     return true;
 249   }
 250 
 251   // Must be native-compiled frame. Since sender will try and use fp to find
 252   // linkages it must be safe
 253 
 254   if (!fp_safe) {
 255     return false;
 256   }
 257 
 258   // Will the pc we fetch be non-zero (which we'll find at the oldest frame)
 259 
 260   if ( (address) this->fp()[return_addr_offset] == NULL) return false;
 261 
 262 
 263   // could try and do some more potential verification of native frame if we could think of some...
 264 
 265   return true;
 266 
 267 }
 268 
 269 
 270 void frame::patch_pc(Thread* thread, address pc) {
 271   address* pc_addr = &(((address*) sp())[-1]);
 272   if (TracePcPatching) {
 273     tty->print_cr("patch_pc at address " INTPTR_FORMAT " [" INTPTR_FORMAT " -> " INTPTR_FORMAT "]",
 274                   p2i(pc_addr), p2i(*pc_addr), p2i(pc));
 275   }
 276   // Either the return address is the original one or we are going to
 277   // patch in the same address that's already there.
 278   assert(_pc == *pc_addr || pc == *pc_addr, "must be");
 279   *pc_addr = pc;
 280   _cb = CodeCache::find_blob(pc);
 281   address original_pc = CompiledMethod::get_deopt_original_pc(this);
 282   if (original_pc != NULL) {
 283     assert(original_pc == _pc, "expected original PC to be stored before patching");
 284     _deopt_state = is_deoptimized;
 285     // leave _pc as is
 286   } else {
 287     _deopt_state = not_deoptimized;
 288     _pc = pc;
 289   }
 290 }
 291 
 292 bool frame::is_interpreted_frame() const  {
 293   return Interpreter::contains(pc());
 294 }
 295 
 296 int frame::frame_size(RegisterMap* map) const {
 297   frame sender = this->sender(map);
 298   return sender.sp() - sp();
 299 }
 300 
 301 intptr_t* frame::entry_frame_argument_at(int offset) const {
 302   // convert offset to index to deal with tsi
 303   int index = (Interpreter::expr_offset_in_bytes(offset)/wordSize);
 304   // Entry frame's arguments are always in relation to unextended_sp()
 305   return &unextended_sp()[index];
 306 }
 307 
 308 // sender_sp
 309 
 310 intptr_t* frame::interpreter_frame_sender_sp() const {
 311   assert(is_interpreted_frame(), "interpreted frame expected");
 312   return (intptr_t*) at(interpreter_frame_sender_sp_offset);
 313 }
 314 
 315 void frame::set_interpreter_frame_sender_sp(intptr_t* sender_sp) {
 316   assert(is_interpreted_frame(), "interpreted frame expected");
 317   ptr_at_put(interpreter_frame_sender_sp_offset, (intptr_t) sender_sp);
 318 }
 319 
 320 
 321 // monitor elements
 322 
 323 BasicObjectLock* frame::interpreter_frame_monitor_begin() const {
 324   return (BasicObjectLock*) addr_at(interpreter_frame_monitor_block_bottom_offset);
 325 }
 326 
 327 BasicObjectLock* frame::interpreter_frame_monitor_end() const {
 328   BasicObjectLock* result = (BasicObjectLock*) *addr_at(interpreter_frame_monitor_block_top_offset);
 329   // make sure the pointer points inside the frame
 330   assert(sp() <= (intptr_t*) result, "monitor end should be above the stack pointer");
 331   assert((intptr_t*) result < fp(),  "monitor end should be strictly below the frame pointer");
 332   return result;
 333 }
 334 
 335 void frame::interpreter_frame_set_monitor_end(BasicObjectLock* value) {
 336   *((BasicObjectLock**)addr_at(interpreter_frame_monitor_block_top_offset)) = value;
 337 }
 338 
 339 // Used by template based interpreter deoptimization
 340 void frame::interpreter_frame_set_last_sp(intptr_t* sp) {
 341     *((intptr_t**)addr_at(interpreter_frame_last_sp_offset)) = sp;
 342 }
 343 
 344 frame frame::sender_for_entry_frame(RegisterMap* map) const {
 345   assert(map != NULL, "map must be set");
 346   // Java frame called from C; skip all C frames and return top C
 347   // frame of that chunk as the sender
 348   JavaFrameAnchor* jfa = entry_frame_call_wrapper()->anchor();
 349   assert(!entry_frame_is_first(), "next Java fp must be non zero");
 350   assert(jfa->last_Java_sp() > sp(), "must be above this frame on stack");
 351   // Since we are walking the stack now this nested anchor is obviously walkable
 352   // even if it wasn't when it was stacked.
 353   if (!jfa->walkable()) {
 354     // Capture _last_Java_pc (if needed) and mark anchor walkable.
 355     jfa->capture_last_Java_pc();
 356   }
 357   map->clear();
 358   assert(map->include_argument_oops(), "should be set by clear");
 359   vmassert(jfa->last_Java_pc() != NULL, "not walkable");
 360   frame fr(jfa->last_Java_sp(), jfa->last_Java_fp(), jfa->last_Java_pc());
 361   return fr;
 362 }
 363 
 364 //------------------------------------------------------------------------------
 365 // frame::verify_deopt_original_pc
 366 //
 367 // Verifies the calculated original PC of a deoptimization PC for the
 368 // given unextended SP.
 369 #ifdef ASSERT
 370 void frame::verify_deopt_original_pc(CompiledMethod* nm, intptr_t* unextended_sp) {
 371   frame fr;
 372 
 373   // This is ugly but it's better than to change {get,set}_original_pc
 374   // to take an SP value as argument.  And it's only a debugging
 375   // method anyway.
 376   fr._unextended_sp = unextended_sp;
 377 
 378   address original_pc = nm->get_original_pc(&fr);
 379   assert(nm->insts_contains_inclusive(original_pc),
 380          "original PC must be in the main code section of the the compiled method (or must be immediately following it)");
 381 }
 382 #endif
 383 
 384 //------------------------------------------------------------------------------
 385 // frame::adjust_unextended_sp
 386 #ifdef ASSERT
 387 void frame::adjust_unextended_sp() {
 388   // On x86, sites calling method handle intrinsics and lambda forms are treated
 389   // as any other call site. Therefore, no special action is needed when we are
 390   // returning to any of these call sites.
 391 
 392   if (_cb != NULL) {
 393     CompiledMethod* sender_cm = _cb->as_compiled_method_or_null();
 394     if (sender_cm != NULL) {
 395       // If the sender PC is a deoptimization point, get the original PC.
 396       if (sender_cm->is_deopt_entry(_pc) ||
 397           sender_cm->is_deopt_mh_entry(_pc)) {
 398         verify_deopt_original_pc(sender_cm, _unextended_sp);
 399       }
 400     }
 401   }
 402 }
 403 #endif
 404 
 405 //------------------------------------------------------------------------------
 406 // frame::update_map_with_saved_link
 407 void frame::update_map_with_saved_link(RegisterMap* map, intptr_t** link_addr) {
 408   // The interpreter and compiler(s) always save EBP/RBP in a known
 409   // location on entry. We must record where that location is
 410   // so this if EBP/RBP was live on callout from c2 we can find
 411   // the saved copy no matter what it called.
 412 
 413   // Since the interpreter always saves EBP/RBP if we record where it is then
 414   // we don't have to always save EBP/RBP on entry and exit to c2 compiled
 415   // code, on entry will be enough.
 416   map->set_location(rbp->as_VMReg(), (address) link_addr);
 417 #ifdef AMD64
 418   // this is weird "H" ought to be at a higher address however the
 419   // oopMaps seems to have the "H" regs at the same address and the
 420   // vanilla register.
 421   // XXXX make this go away
 422   if (true) {
 423     map->set_location(rbp->as_VMReg()->next(), (address) link_addr);
 424   }
 425 #endif // AMD64
 426 }
 427 
 428 
 429 //------------------------------------------------------------------------------
 430 // frame::sender_for_interpreter_frame
 431 frame frame::sender_for_interpreter_frame(RegisterMap* map) const {
 432   // SP is the raw SP from the sender after adapter or interpreter
 433   // extension.
 434   intptr_t* sender_sp = this->sender_sp();
 435 
 436   // This is the sp before any possible extension (adapter/locals).
 437   intptr_t* unextended_sp = interpreter_frame_sender_sp();
 438 
 439 #if COMPILER2_OR_JVMCI
 440   if (map->update_map()) {
 441     update_map_with_saved_link(map, (intptr_t**) addr_at(link_offset));
 442   }
 443 #endif // COMPILER2_OR_JVMCI
 444 
 445   return frame(sender_sp, unextended_sp, link(), sender_pc());
 446 }
 447 
 448 
 449 //------------------------------------------------------------------------------
 450 // frame::sender_for_compiled_frame
 451 frame frame::sender_for_compiled_frame(RegisterMap* map) const {
 452   assert(map != NULL, "map must be set");
 453 
 454   // frame owned by optimizing compiler
 455   assert(_cb->frame_size() >= 0, "must have non-zero frame size");
 456   intptr_t* sender_sp = unextended_sp() + _cb->frame_size();
 457   intptr_t* unextended_sp = sender_sp;
 458 
 459   // On Intel the return_address is always the word on the stack
 460   address sender_pc = (address) *(sender_sp-1);
 461 
 462   // This is the saved value of EBP which may or may not really be an FP.
 463   // It is only an FP if the sender is an interpreter frame (or C1?).
 464   intptr_t** saved_fp_addr = (intptr_t**) (sender_sp - frame::sender_sp_offset);
 465 
 466   if (map->update_map()) {
 467     // Tell GC to use argument oopmaps for some runtime stubs that need it.
 468     // For C1, the runtime stub might not have oop maps, so set this flag
 469     // outside of update_register_map.
 470     map->set_include_argument_oops(_cb->caller_must_gc_arguments(map->thread()));
 471     if (_cb->oop_maps() != NULL) {
 472       OopMapSet::update_register_map(this, map);
 473     }
 474 
 475     // Since the prolog does the save and restore of EBP there is no oopmap
 476     // for it so we must fill in its location as if there was an oopmap entry
 477     // since if our caller was compiled code there could be live jvm state in it.
 478     update_map_with_saved_link(map, saved_fp_addr);
 479   }
 480 
 481   assert(sender_sp != sp(), "must have changed");
 482   return frame(sender_sp, unextended_sp, *saved_fp_addr, sender_pc);
 483 }
 484 
 485 
 486 //------------------------------------------------------------------------------
 487 // frame::sender
 488 frame frame::sender(RegisterMap* map) const {
 489   // Default is we done have to follow them. The sender_for_xxx will
 490   // update it accordingly
 491   map->set_include_argument_oops(false);
 492 
 493   if (is_entry_frame())       return sender_for_entry_frame(map);
 494   if (is_interpreted_frame()) return sender_for_interpreter_frame(map);
 495   assert(_cb == CodeCache::find_blob(pc()),"Must be the same");
 496 
 497   if (_cb != NULL) {
 498     return sender_for_compiled_frame(map);
 499   }
 500   // Must be native-compiled frame, i.e. the marshaling code for native
 501   // methods that exists in the core system.
 502   return frame(sender_sp(), link(), sender_pc());
 503 }
 504 
 505 bool frame::is_interpreted_frame_valid(JavaThread* thread) const {
 506   assert(is_interpreted_frame(), "Not an interpreted frame");
 507   // These are reasonable sanity checks
 508   if (fp() == 0 || (intptr_t(fp()) & (wordSize-1)) != 0) {
 509     return false;
 510   }
 511   if (sp() == 0 || (intptr_t(sp()) & (wordSize-1)) != 0) {
 512     return false;
 513   }
 514   if (fp() + interpreter_frame_initial_sp_offset < sp()) {
 515     return false;
 516   }
 517   // These are hacks to keep us out of trouble.
 518   // The problem with these is that they mask other problems
 519   if (fp() <= sp()) {        // this attempts to deal with unsigned comparison above
 520     return false;
 521   }
 522 
 523   // do some validation of frame elements
 524   // first the method
 525 
 526   Method* m = *interpreter_frame_method_addr();
 527 
 528   // validate the method we'd find in this potential sender
 529   if (!Method::is_valid_method(m)) return false;
 530 
 531   // stack frames shouldn't be much larger than max_stack elements
 532   // this test requires the use the unextended_sp which is the sp as seen by
 533   // the current frame, and not sp which is the "raw" pc which could point
 534   // further because of local variables of the callee method inserted after
 535   // method arguments
 536   if (fp() - unextended_sp() > 1024 + m->max_stack()*Interpreter::stackElementSize) {
 537     return false;
 538   }
 539 
 540   // validate bci/bcp
 541 
 542   address bcp = interpreter_frame_bcp();
 543   if (m->validate_bci_from_bcp(bcp) < 0) {
 544     return false;
 545   }
 546 
 547   // validate ConstantPoolCache*
 548   ConstantPoolCache* cp = *interpreter_frame_cache_addr();
 549   if (cp == NULL || !cp->is_metaspace_object()) return false;
 550 
 551   // validate locals
 552 
 553   address locals =  (address) *interpreter_frame_locals_addr();
 554 
 555   if (locals > thread->stack_base() || locals < (address) fp()) return false;
 556 
 557   // We'd have to be pretty unlucky to be mislead at this point
 558   return true;
 559 }
 560 
 561 BasicType frame::interpreter_frame_result(oop* oop_result, jvalue* value_result) {
 562   assert(is_interpreted_frame(), "interpreted frame expected");
 563   Method* method = interpreter_frame_method();
 564   BasicType type = method->result_type();
 565 
 566   intptr_t* tos_addr;
 567   if (method->is_native()) {
 568     // Prior to calling into the runtime to report the method_exit the possible
 569     // return value is pushed to the native stack. If the result is a jfloat/jdouble
 570     // then ST0 is saved before EAX/EDX. See the note in generate_native_result
 571     tos_addr = (intptr_t*)sp();
 572     if (type == T_FLOAT || type == T_DOUBLE) {
 573     // QQQ seems like this code is equivalent on the two platforms
 574 #ifdef AMD64
 575       // This is times two because we do a push(ltos) after pushing XMM0
 576       // and that takes two interpreter stack slots.
 577       tos_addr += 2 * Interpreter::stackElementWords;
 578 #else
 579       tos_addr += 2;
 580 #endif // AMD64
 581     }
 582   } else {
 583     tos_addr = (intptr_t*)interpreter_frame_tos_address();
 584   }
 585 
 586   switch (type) {
 587     case T_OBJECT  :
 588     case T_ARRAY   : {
 589       oop obj;
 590       if (method->is_native()) {
 591         obj = cast_to_oop(at(interpreter_frame_oop_temp_offset));
 592       } else {
 593         oop* obj_p = (oop*)tos_addr;
 594         obj = (obj_p == NULL) ? (oop)NULL : *obj_p;
 595       }
 596       assert(obj == NULL || Universe::heap()->is_in(obj), "sanity check");
 597       *oop_result = obj;
 598       break;
 599     }
 600     case T_BOOLEAN : value_result->z = *(jboolean*)tos_addr; break;
 601     case T_BYTE    : value_result->b = *(jbyte*)tos_addr; break;
 602     case T_CHAR    : value_result->c = *(jchar*)tos_addr; break;
 603     case T_SHORT   : value_result->s = *(jshort*)tos_addr; break;
 604     case T_INT     : value_result->i = *(jint*)tos_addr; break;
 605     case T_LONG    : value_result->j = *(jlong*)tos_addr; break;
 606     case T_FLOAT   : {
 607 #ifdef AMD64
 608         value_result->f = *(jfloat*)tos_addr;
 609 #else
 610       if (method->is_native()) {
 611         jdouble d = *(jdouble*)tos_addr;  // Result was in ST0 so need to convert to jfloat
 612         value_result->f = (jfloat)d;
 613       } else {
 614         value_result->f = *(jfloat*)tos_addr;
 615       }
 616 #endif // AMD64
 617       break;
 618     }
 619     case T_DOUBLE  : value_result->d = *(jdouble*)tos_addr; break;
 620     case T_VOID    : /* Nothing to do */ break;
 621     default        : ShouldNotReachHere();
 622   }
 623 
 624   return type;
 625 }
 626 
 627 
 628 intptr_t* frame::interpreter_frame_tos_at(jint offset) const {
 629   int index = (Interpreter::expr_offset_in_bytes(offset)/wordSize);
 630   return &interpreter_frame_tos_address()[index];
 631 }
 632 
 633 #ifndef PRODUCT
 634 
 635 #define DESCRIBE_FP_OFFSET(name) \
 636   values.describe(frame_no, fp() + frame::name##_offset, #name)
 637 
 638 void frame::describe_pd(FrameValues& values, int frame_no) {
 639   if (is_interpreted_frame()) {
 640     DESCRIBE_FP_OFFSET(interpreter_frame_sender_sp);
 641     DESCRIBE_FP_OFFSET(interpreter_frame_last_sp);
 642     DESCRIBE_FP_OFFSET(interpreter_frame_method);
 643     DESCRIBE_FP_OFFSET(interpreter_frame_mirror);
 644     DESCRIBE_FP_OFFSET(interpreter_frame_mdp);
 645     DESCRIBE_FP_OFFSET(interpreter_frame_cache);
 646     DESCRIBE_FP_OFFSET(interpreter_frame_vt_alloc_ptr);
 647     DESCRIBE_FP_OFFSET(interpreter_frame_locals);
 648     DESCRIBE_FP_OFFSET(interpreter_frame_bcp);
 649     DESCRIBE_FP_OFFSET(interpreter_frame_initial_sp);
 650 #ifdef AMD64
 651   } else if (is_entry_frame()) {
 652     // This could be more descriptive if we use the enum in
 653     // stubGenerator to map to real names but it's most important to
 654     // claim these frame slots so the error checking works.
 655     for (int i = 0; i < entry_frame_after_call_words; i++) {
 656       values.describe(frame_no, fp() - i, err_msg("call_stub word fp - %d", i));
 657     }
 658 #endif // AMD64
 659   }
 660 }
 661 #endif // !PRODUCT
 662 
 663 intptr_t *frame::initial_deoptimization_info() {
 664   // used to reset the saved FP
 665   return fp();
 666 }
 667 
 668 intptr_t* frame::real_fp() const {
 669   if (_cb != NULL) {
 670     // use the frame size if valid
 671     int size = _cb->frame_size();
 672     if (size > 0) {
 673       return unextended_sp() + size;
 674     }
 675   }
 676   // else rely on fp()
 677   assert(! is_compiled_frame(), "unknown compiled frame size");
 678   return fp();
 679 }
 680 
 681 #ifndef PRODUCT
 682 // This is a generic constructor which is only used by pns() in debug.cpp.
 683 frame::frame(void* sp, void* fp, void* pc) {
 684   init((intptr_t*)sp, (intptr_t*)fp, (address)pc);
 685 }
 686 
 687 void frame::pd_ps() {}
 688 #endif
 689 
 690 void JavaFrameAnchor::make_walkable(JavaThread* thread) {
 691   // last frame set?
 692   if (last_Java_sp() == NULL) return;
 693   // already walkable?
 694   if (walkable()) return;
 695   vmassert(Thread::current() == (Thread*)thread, "not current thread");
 696   vmassert(last_Java_sp() != NULL, "not called from Java code?");
 697   vmassert(last_Java_pc() == NULL, "already walkable");
 698   capture_last_Java_pc();
 699   vmassert(walkable(), "something went wrong");
 700 }
 701 
 702 void JavaFrameAnchor::capture_last_Java_pc() {
 703   vmassert(_last_Java_sp != NULL, "no last frame set");
 704   vmassert(_last_Java_pc == NULL, "already walkable");
 705   _last_Java_pc = (address)_last_Java_sp[-1];
 706 }