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 "code/codeCache.hpp"
  27 #include "interpreter/interpreter.hpp"
  28 #include "memory/resourceArea.hpp"
  29 #include "memory/universe.hpp"
  30 #include "oops/markOop.hpp"
  31 #include "oops/method.hpp"
  32 #include "oops/oop.inline.hpp"
  33 #include "prims/methodHandles.hpp"
  34 #include "runtime/frame.inline.hpp"
  35 #include "runtime/handles.inline.hpp"
  36 #include "runtime/javaCalls.hpp"
  37 #include "runtime/monitorChunk.hpp"
  38 #include "runtime/signature.hpp"
  39 #include "runtime/stubCodeGenerator.hpp"
  40 #include "runtime/stubRoutines.hpp"
  41 #include "vmreg_sparc.inline.hpp"
  42 #ifdef COMPILER1
  43 #include "c1/c1_Runtime1.hpp"
  44 #include "runtime/vframeArray.hpp"
  45 #endif
  46 
  47 void RegisterMap::pd_clear() {
  48   if (_thread->has_last_Java_frame()) {
  49     frame fr = _thread->last_frame();
  50     _window = fr.sp();
  51   } else {
  52     _window = NULL;
  53   }
  54   _younger_window = NULL;
  55 }
  56 
  57 
  58 // Unified register numbering scheme: each 32-bits counts as a register
  59 // number, so all the V9 registers take 2 slots.
  60 const static int R_L_nums[] = {0+040,2+040,4+040,6+040,8+040,10+040,12+040,14+040};
  61 const static int R_I_nums[] = {0+060,2+060,4+060,6+060,8+060,10+060,12+060,14+060};
  62 const static int R_O_nums[] = {0+020,2+020,4+020,6+020,8+020,10+020,12+020,14+020};
  63 const static int R_G_nums[] = {0+000,2+000,4+000,6+000,8+000,10+000,12+000,14+000};
  64 static RegisterMap::LocationValidType bad_mask = 0;
  65 static RegisterMap::LocationValidType R_LIO_mask = 0;
  66 static bool register_map_inited = false;
  67 
  68 static void register_map_init() {
  69   if (!register_map_inited) {
  70     register_map_inited = true;
  71     int i;
  72     for (i = 0; i < 8; i++) {
  73       assert(R_L_nums[i] < RegisterMap::location_valid_type_size, "in first chunk");
  74       assert(R_I_nums[i] < RegisterMap::location_valid_type_size, "in first chunk");
  75       assert(R_O_nums[i] < RegisterMap::location_valid_type_size, "in first chunk");
  76       assert(R_G_nums[i] < RegisterMap::location_valid_type_size, "in first chunk");
  77     }
  78 
  79     bad_mask |= (1LL << R_O_nums[6]); // SP
  80     bad_mask |= (1LL << R_O_nums[7]); // cPC
  81     bad_mask |= (1LL << R_I_nums[6]); // FP
  82     bad_mask |= (1LL << R_I_nums[7]); // rPC
  83     bad_mask |= (1LL << R_G_nums[2]); // TLS
  84     bad_mask |= (1LL << R_G_nums[7]); // reserved by libthread
  85 
  86     for (i = 0; i < 8; i++) {
  87       R_LIO_mask |= (1LL << R_L_nums[i]);
  88       R_LIO_mask |= (1LL << R_I_nums[i]);
  89       R_LIO_mask |= (1LL << R_O_nums[i]);
  90     }
  91   }
  92 }
  93 
  94 
  95 address RegisterMap::pd_location(VMReg regname) const {
  96   register_map_init();
  97 
  98   assert(regname->is_reg(), "sanity check");
  99   // Only the GPRs get handled this way
 100   if( !regname->is_Register())
 101     return NULL;
 102 
 103   // don't talk about bad registers
 104   if ((bad_mask & ((LocationValidType)1 << regname->value())) != 0) {
 105     return NULL;
 106   }
 107 
 108   // Convert to a GPR
 109   Register reg;
 110   int second_word = 0;
 111   // 32-bit registers for in, out and local
 112   if (!regname->is_concrete()) {
 113     // HMM ought to return NULL for any non-concrete (odd) vmreg
 114     // this all tied up in the fact we put out double oopMaps for
 115     // register locations. When that is fixed we'd will return NULL
 116     // (or assert here).
 117     reg = regname->prev()->as_Register();
 118     second_word = sizeof(jint);
 119   } else {
 120     reg = regname->as_Register();
 121   }
 122   if (reg->is_out()) {
 123     return _younger_window == NULL ? NULL :
 124       second_word + (address)&_younger_window[reg->after_save()->sp_offset_in_saved_window()];
 125   }
 126   if (reg->is_local() || reg->is_in()) {
 127     assert(_window != NULL, "Window should be available");
 128     return second_word + (address)&_window[reg->sp_offset_in_saved_window()];
 129   }
 130   // Only the window'd GPRs get handled this way; not the globals.
 131   return NULL;
 132 }
 133 
 134 
 135 #ifdef ASSERT
 136 void RegisterMap::check_location_valid() {
 137   register_map_init();
 138   assert((_location_valid[0] & bad_mask) == 0, "cannot have special locations for SP,FP,TLS,etc.");
 139 }
 140 #endif
 141 
 142 // We are shifting windows.  That means we are moving all %i to %o,
 143 // getting rid of all current %l, and keeping all %g.  This is only
 144 // complicated if any of the location pointers for these are valid.
 145 // The normal case is that everything is in its standard register window
 146 // home, and _location_valid[0] is zero.  In that case, this routine
 147 // does exactly nothing.
 148 void RegisterMap::shift_individual_registers() {
 149   if (!update_map())  return;  // this only applies to maps with locations
 150   register_map_init();
 151   check_location_valid();
 152 
 153   LocationValidType lv = _location_valid[0];
 154   LocationValidType lv0 = lv;
 155 
 156   lv &= ~R_LIO_mask;  // clear %l, %o, %i regs
 157 
 158   // if we cleared some non-%g locations, we may have to do some shifting
 159   if (lv != lv0) {
 160     // copy %i0-%i5 to %o0-%o5, if they have special locations
 161     // This can happen in within stubs which spill argument registers
 162     // around a dynamic link operation, such as resolve_opt_virtual_call.
 163     for (int i = 0; i < 8; i++) {
 164       if (lv0 & (1LL << R_I_nums[i])) {
 165         _location[R_O_nums[i]] = _location[R_I_nums[i]];
 166         lv |=  (1LL << R_O_nums[i]);
 167       }
 168     }
 169   }
 170 
 171   _location_valid[0] = lv;
 172   check_location_valid();
 173 }
 174 
 175 bool frame::safe_for_sender(JavaThread *thread) {
 176 
 177   address _SP = (address) sp();
 178   address _FP = (address) fp();
 179   address _UNEXTENDED_SP = (address) unextended_sp();
 180   // sp must be within the stack
 181   bool sp_safe = (_SP <= thread->stack_base()) &&
 182                  (_SP >= thread->stack_base() - thread->stack_size());
 183 
 184   if (!sp_safe) {
 185     return false;
 186   }
 187 
 188   // unextended sp must be within the stack and above or equal sp
 189   bool unextended_sp_safe = (_UNEXTENDED_SP <= thread->stack_base()) &&
 190                             (_UNEXTENDED_SP >= _SP);
 191 
 192   if (!unextended_sp_safe) return false;
 193 
 194   // an fp must be within the stack and above (but not equal) sp
 195   bool fp_safe = (_FP <= thread->stack_base()) &&
 196                  (_FP > _SP);
 197 
 198   // We know sp/unextended_sp are safe only fp is questionable here
 199 
 200   // If the current frame is known to the code cache then we can attempt to
 201   // to construct the sender and do some validation of it. This goes a long way
 202   // toward eliminating issues when we get in frame construction code
 203 
 204   if (_cb != NULL ) {
 205 
 206     // First check if frame is complete and tester is reliable
 207     // Unfortunately we can only check frame complete for runtime stubs and nmethod
 208     // other generic buffer blobs are more problematic so we just assume they are
 209     // ok. adapter blobs never have a frame complete and are never ok.
 210 
 211     if (!_cb->is_frame_complete_at(_pc)) {
 212       if (_cb->is_compiled() || _cb->is_adapter_blob() || _cb->is_runtime_stub()) {
 213         return false;
 214       }
 215     }
 216 
 217     // Could just be some random pointer within the codeBlob
 218     if (!_cb->code_contains(_pc)) {
 219       return false;
 220     }
 221 
 222     // Entry frame checks
 223     if (is_entry_frame()) {
 224       // an entry frame must have a valid fp.
 225       return fp_safe && is_entry_frame_valid(thread);
 226     }
 227 
 228     intptr_t* younger_sp = sp();
 229     intptr_t* _SENDER_SP = sender_sp(); // sender is actually just _FP
 230     bool adjusted_stack = is_interpreted_frame();
 231 
 232     address   sender_pc = (address)younger_sp[I7->sp_offset_in_saved_window()] + pc_return_offset;
 233 
 234 
 235     // We must always be able to find a recognizable pc
 236     CodeBlob* sender_blob = CodeCache::find_blob_unsafe(sender_pc);
 237     if (sender_pc == NULL ||  sender_blob == NULL) {
 238       return false;
 239     }
 240 
 241     // Could be a zombie method
 242     if (sender_blob->is_zombie() || sender_blob->is_unloaded()) {
 243       return false;
 244     }
 245 
 246     // It should be safe to construct the sender though it might not be valid
 247 
 248     frame sender(_SENDER_SP, younger_sp, adjusted_stack);
 249 
 250     // Do we have a valid fp?
 251     address sender_fp = (address) sender.fp();
 252 
 253     // an fp must be within the stack and above (but not equal) current frame's _FP
 254 
 255     bool sender_fp_safe = (sender_fp <= thread->stack_base()) &&
 256                    (sender_fp > _FP);
 257 
 258     if (!sender_fp_safe) {
 259       return false;
 260     }
 261 
 262 
 263     // If the potential sender is the interpreter then we can do some more checking
 264     if (Interpreter::contains(sender_pc)) {
 265       return sender.is_interpreted_frame_valid(thread);
 266     }
 267 
 268     // Could just be some random pointer within the codeBlob
 269     if (!sender.cb()->code_contains(sender_pc)) {
 270       return false;
 271     }
 272 
 273     // We should never be able to see an adapter if the current frame is something from code cache
 274     if (sender_blob->is_adapter_blob()) {
 275       return false;
 276     }
 277 
 278     if (sender.is_entry_frame()) {
 279       // Validate the JavaCallWrapper an entry frame must have
 280 
 281       address jcw = (address)sender.entry_frame_call_wrapper();
 282 
 283       bool jcw_safe = (jcw <= thread->stack_base()) && (jcw > sender_fp);
 284 
 285       return jcw_safe;
 286     }
 287 
 288     // If the frame size is 0 something (or less) is bad because every nmethod has a non-zero frame size
 289     // because you must allocate window space
 290 
 291     if (sender_blob->frame_size() <= 0) {
 292       assert(!sender_blob->is_compiled(), "should count return address at least");
 293       return false;
 294     }
 295 
 296     // The sender should positively be an nmethod or call_stub. On sparc we might in fact see something else.
 297     // The cause of this is because at a save instruction the O7 we get is a leftover from an earlier
 298     // window use. So if a runtime stub creates two frames (common in fastdebug/debug) then we see the
 299     // stale pc. So if the sender blob is not something we'd expect we have little choice but to declare
 300     // the stack unwalkable. pd_get_top_frame_for_signal_handler tries to recover from this by unwinding
 301     // that initial frame and retrying.
 302 
 303     if (!sender_blob->is_compiled()) {
 304       return false;
 305     }
 306 
 307     // Could put some more validation for the potential non-interpreted sender
 308     // frame we'd create by calling sender if I could think of any. Wait for next crash in forte...
 309 
 310     // One idea is seeing if the sender_pc we have is one that we'd expect to call to current cb
 311 
 312     // We've validated the potential sender that would be created
 313 
 314     return true;
 315 
 316   }
 317 
 318   // Must be native-compiled frame. Since sender will try and use fp to find
 319   // linkages it must be safe
 320 
 321   if (!fp_safe) return false;
 322 
 323   // could try and do some more potential verification of native frame if we could think of some...
 324 
 325   return true;
 326 }
 327 
 328 // constructors
 329 
 330 // Construct an unpatchable, deficient frame
 331 void frame::init(intptr_t* sp, address pc, CodeBlob* cb) {
 332   assert( (((intptr_t)sp & (wordSize-1)) == 0), "frame constructor passed an invalid sp");
 333   _sp = sp;
 334   _younger_sp = NULL;
 335   _pc = pc;
 336   _cb = cb;
 337   _sp_adjustment_by_callee = 0;
 338   assert(pc == NULL && cb == NULL || pc != NULL, "can't have a cb and no pc!");
 339   if (_cb == NULL && _pc != NULL ) {
 340     _cb = CodeCache::find_blob(_pc);
 341   }
 342   _deopt_state = unknown;
 343 }
 344 
 345 frame::frame(intptr_t* sp, unpatchable_t, address pc, CodeBlob* cb) {
 346   init(sp, pc, cb);
 347 }
 348 
 349 frame::frame(intptr_t* sp, intptr_t* younger_sp, bool younger_frame_is_interpreted) :
 350   _sp(sp),
 351   _younger_sp(younger_sp),
 352   _deopt_state(unknown),
 353   _sp_adjustment_by_callee(0) {
 354   if (younger_sp == NULL) {
 355     // make a deficient frame which doesn't know where its PC is
 356     _pc = NULL;
 357     _cb = NULL;
 358   } else {
 359     _pc = (address)younger_sp[I7->sp_offset_in_saved_window()] + pc_return_offset;
 360     assert( (intptr_t*)younger_sp[FP->sp_offset_in_saved_window()] == (intptr_t*)((intptr_t)sp - STACK_BIAS), "younger_sp must be valid");
 361     // Any frame we ever build should always "safe" therefore we should not have to call
 362     // find_blob_unsafe
 363     // In case of native stubs, the pc retrieved here might be
 364     // wrong.  (the _last_native_pc will have the right value)
 365     // So do not put add any asserts on the _pc here.
 366   }
 367 
 368   if (_pc != NULL)
 369     _cb = CodeCache::find_blob(_pc);
 370 
 371   // Check for MethodHandle call sites.
 372   if (_cb != NULL) {
 373     CompiledMethod* nm = _cb->as_compiled_method_or_null();
 374     if (nm != NULL) {
 375       if (nm->is_deopt_mh_entry(_pc) || nm->is_method_handle_return(_pc)) {
 376         _sp_adjustment_by_callee = (intptr_t*) ((intptr_t) sp[L7_mh_SP_save->sp_offset_in_saved_window()] + STACK_BIAS) - sp;
 377         // The SP is already adjusted by this MH call site, don't
 378         // overwrite this value with the wrong interpreter value.
 379         younger_frame_is_interpreted = false;
 380       }
 381     }
 382   }
 383 
 384   if (younger_frame_is_interpreted) {
 385     // compute adjustment to this frame's SP made by its interpreted callee
 386     _sp_adjustment_by_callee = (intptr_t*) ((intptr_t) younger_sp[I5_savedSP->sp_offset_in_saved_window()] + STACK_BIAS) - sp;
 387   }
 388 
 389   // It is important that the frame is fully constructed when we do
 390   // this lookup as get_deopt_original_pc() needs a correct value for
 391   // unextended_sp() which uses _sp_adjustment_by_callee.
 392   if (_pc != NULL) {
 393     address original_pc = CompiledMethod::get_deopt_original_pc(this);
 394     if (original_pc != NULL) {
 395       _pc = original_pc;
 396       _deopt_state = is_deoptimized;
 397     } else {
 398       _deopt_state = not_deoptimized;
 399     }
 400   }
 401 }
 402 
 403 #ifndef PRODUCT
 404 // This is a generic constructor which is only used by pns() in debug.cpp.
 405 frame::frame(void* sp, void* fp, void* pc) {
 406   init((intptr_t*)sp, (address)pc, NULL);
 407 }
 408 
 409 extern "C" void findpc(intptr_t x);
 410 
 411 void frame::pd_ps() {
 412   intptr_t* curr_sp = sp();
 413   intptr_t* prev_sp = curr_sp - 1;
 414   intptr_t *pc = NULL;
 415   intptr_t *next_pc = NULL;
 416   int count = 0;
 417   tty->print_cr("register window backtrace from " INTPTR_FORMAT ":", p2i(curr_sp));
 418   while (curr_sp != NULL && ((intptr_t)curr_sp & 7) == 0 && curr_sp > prev_sp && curr_sp < prev_sp+1000) {
 419     pc      = next_pc;
 420     next_pc = (intptr_t*) curr_sp[I7->sp_offset_in_saved_window()];
 421     tty->print("[%d] curr_sp=" INTPTR_FORMAT " pc=", count, p2i(curr_sp));
 422     findpc((intptr_t)pc);
 423     if (WizardMode && Verbose) {
 424       // print register window contents also
 425       tty->print_cr("    L0..L7: {"
 426                     INTPTR_FORMAT " " INTPTR_FORMAT " " INTPTR_FORMAT " " INTPTR_FORMAT " "
 427                     INTPTR_FORMAT " " INTPTR_FORMAT " " INTPTR_FORMAT " " INTPTR_FORMAT " ",
 428                     curr_sp[0+0], curr_sp[0+1], curr_sp[0+2], curr_sp[0+3],
 429                     curr_sp[0+4], curr_sp[0+5], curr_sp[0+6], curr_sp[0+7]);
 430       tty->print_cr("    I0..I7: {"
 431                     INTPTR_FORMAT " " INTPTR_FORMAT " " INTPTR_FORMAT " " INTPTR_FORMAT " "
 432                     INTPTR_FORMAT " " INTPTR_FORMAT " " INTPTR_FORMAT " " INTPTR_FORMAT " ",
 433                     curr_sp[8+0], curr_sp[8+1], curr_sp[8+2], curr_sp[8+3],
 434                     curr_sp[8+4], curr_sp[8+5], curr_sp[8+6], curr_sp[8+7]);
 435       // (and print stack frame contents too??)
 436 
 437       CodeBlob *b = CodeCache::find_blob((address) pc);
 438       if (b != NULL) {
 439         if (b->is_nmethod()) {
 440           Method* m = ((nmethod*)b)->method();
 441           int nlocals = m->max_locals();
 442           int nparams  = m->size_of_parameters();
 443           tty->print_cr("compiled java method (locals = %d, params = %d)", nlocals, nparams);
 444         }
 445       }
 446     }
 447     prev_sp = curr_sp;
 448     curr_sp = (intptr_t *)curr_sp[FP->sp_offset_in_saved_window()];
 449     curr_sp = (intptr_t *)((intptr_t)curr_sp + STACK_BIAS);
 450     count += 1;
 451   }
 452   if (curr_sp != NULL)
 453     tty->print("[%d] curr_sp=" INTPTR_FORMAT " [bogus sp!]", count, p2i(curr_sp));
 454 }
 455 
 456 #endif // PRODUCT
 457 
 458 bool frame::is_interpreted_frame() const  {
 459   return Interpreter::contains(pc());
 460 }
 461 
 462 // sender_sp
 463 
 464 intptr_t* frame::interpreter_frame_sender_sp() const {
 465   assert(is_interpreted_frame(), "interpreted frame expected");
 466   return fp();
 467 }
 468 
 469 void frame::set_interpreter_frame_sender_sp(intptr_t* sender_sp) {
 470   assert(is_interpreted_frame(), "interpreted frame expected");
 471   Unimplemented();
 472 }
 473 
 474 frame frame::sender_for_entry_frame(RegisterMap *map) const {
 475   assert(map != NULL, "map must be set");
 476   // Java frame called from C; skip all C frames and return top C
 477   // frame of that chunk as the sender
 478   JavaFrameAnchor* jfa = entry_frame_call_wrapper()->anchor();
 479   assert(!entry_frame_is_first(), "next Java fp must be non zero");
 480   assert(jfa->last_Java_sp() > _sp, "must be above this frame on stack");
 481   intptr_t* last_Java_sp = jfa->last_Java_sp();
 482   // Since we are walking the stack now this nested anchor is obviously walkable
 483   // even if it wasn't when it was stacked.
 484   if (!jfa->walkable()) {
 485     // Capture _last_Java_pc (if needed) and mark anchor walkable.
 486     jfa->capture_last_Java_pc(_sp);
 487   }
 488   assert(jfa->last_Java_pc() != NULL, "No captured pc!");
 489   map->clear();
 490   map->make_integer_regs_unsaved();
 491   map->shift_window(last_Java_sp, NULL);
 492   assert(map->include_argument_oops(), "should be set by clear");
 493   return frame(last_Java_sp, frame::unpatchable, jfa->last_Java_pc());
 494 }
 495 
 496 frame frame::sender_for_interpreter_frame(RegisterMap *map) const {
 497   ShouldNotCallThis();
 498   return sender(map);
 499 }
 500 
 501 frame frame::sender_for_compiled_frame(RegisterMap *map) const {
 502   ShouldNotCallThis();
 503   return sender(map);
 504 }
 505 
 506 frame frame::sender(RegisterMap* map) const {
 507   assert(map != NULL, "map must be set");
 508 
 509   assert(CodeCache::find_blob_unsafe(_pc) == _cb, "inconsistent");
 510 
 511   // Default is not to follow arguments; update it accordingly below
 512   map->set_include_argument_oops(false);
 513 
 514   if (is_entry_frame()) return sender_for_entry_frame(map);
 515 
 516   intptr_t* younger_sp = sp();
 517   intptr_t* sp         = sender_sp();
 518 
 519   // Note:  The version of this operation on any platform with callee-save
 520   //        registers must update the register map (if not null).
 521   //        In order to do this correctly, the various subtypes of
 522   //        of frame (interpreted, compiled, glue, native),
 523   //        must be distinguished.  There is no need on SPARC for
 524   //        such distinctions, because all callee-save registers are
 525   //        preserved for all frames via SPARC-specific mechanisms.
 526   //
 527   //        *** HOWEVER, *** if and when we make any floating-point
 528   //        registers callee-saved, then we will have to copy over
 529   //        the RegisterMap update logic from the Intel code.
 530 
 531   // The constructor of the sender must know whether this frame is interpreted so it can set the
 532   // sender's _sp_adjustment_by_callee field.  An osr adapter frame was originally
 533   // interpreted but its pc is in the code cache (for c1 -> osr_frame_return_id stub), so it must be
 534   // explicitly recognized.
 535 
 536 
 537   bool frame_is_interpreted = is_interpreted_frame();
 538   if (frame_is_interpreted) {
 539     map->make_integer_regs_unsaved();
 540     map->shift_window(sp, younger_sp);
 541   } else if (_cb != NULL) {
 542     // Update the locations of implicitly saved registers to be their
 543     // addresses in the register save area.
 544     // For %o registers, the addresses of %i registers in the next younger
 545     // frame are used.
 546     map->shift_window(sp, younger_sp);
 547     if (map->update_map()) {
 548       // Tell GC to use argument oopmaps for some runtime stubs that need it.
 549       // For C1, the runtime stub might not have oop maps, so set this flag
 550       // outside of update_register_map.
 551       map->set_include_argument_oops(_cb->caller_must_gc_arguments(map->thread()));
 552       if (_cb->oop_maps() != NULL) {
 553         OopMapSet::update_register_map(this, map);
 554       }
 555     }
 556   }
 557   return frame(sp, younger_sp, frame_is_interpreted);
 558 }
 559 
 560 
 561 void frame::patch_pc(Thread* thread, address pc) {
 562   vmassert(_deopt_state != unknown, "frame is unpatchable");
 563   if(thread == Thread::current()) {
 564    StubRoutines::Sparc::flush_callers_register_windows_func()();
 565   }
 566   if (TracePcPatching) {
 567     // QQQ this assert is invalid (or too strong anyway) sice _pc could
 568     // be original pc and frame could have the deopt pc.
 569     // assert(_pc == *O7_addr() + pc_return_offset, "frame has wrong pc");
 570     tty->print_cr("patch_pc at address " INTPTR_FORMAT " [" INTPTR_FORMAT " -> " INTPTR_FORMAT "]",
 571                   p2i(O7_addr()), p2i(_pc), p2i(pc));
 572   }
 573   _cb = CodeCache::find_blob(pc);
 574   *O7_addr() = pc - pc_return_offset;
 575   _cb = CodeCache::find_blob(_pc);
 576   address original_pc = CompiledMethod::get_deopt_original_pc(this);
 577   if (original_pc != NULL) {
 578     assert(original_pc == _pc, "expected original to be stored before patching");
 579     _deopt_state = is_deoptimized;
 580   } else {
 581     _deopt_state = not_deoptimized;
 582   }
 583 }
 584 
 585 
 586 static bool sp_is_valid(intptr_t* old_sp, intptr_t* young_sp, intptr_t* sp) {
 587   return (((intptr_t)sp & (2*wordSize-1)) == 0 &&
 588           sp <= old_sp &&
 589           sp >= young_sp);
 590 }
 591 
 592 
 593 /*
 594   Find the (biased) sp that is just younger than old_sp starting at sp.
 595   If not found return NULL. Register windows are assumed to be flushed.
 596 */
 597 intptr_t* frame::next_younger_sp_or_null(intptr_t* old_sp, intptr_t* sp) {
 598 
 599   intptr_t* previous_sp = NULL;
 600   intptr_t* orig_sp = sp;
 601 
 602   int max_frames = (old_sp - sp) / 16; // Minimum frame size is 16
 603   int max_frame2 = max_frames;
 604   while(sp != old_sp && sp_is_valid(old_sp, orig_sp, sp)) {
 605     if (max_frames-- <= 0)
 606       // too many frames have gone by; invalid parameters given to this function
 607       break;
 608     previous_sp = sp;
 609     sp = (intptr_t*)sp[FP->sp_offset_in_saved_window()];
 610     sp = (intptr_t*)((intptr_t)sp + STACK_BIAS);
 611   }
 612 
 613   return (sp == old_sp ? previous_sp : NULL);
 614 }
 615 
 616 /*
 617   Determine if "sp" is a valid stack pointer. "sp" is assumed to be younger than
 618   "valid_sp". So if "sp" is valid itself then it should be possible to walk frames
 619   from "sp" to "valid_sp". The assumption is that the registers windows for the
 620   thread stack in question are flushed.
 621 */
 622 bool frame::is_valid_stack_pointer(intptr_t* valid_sp, intptr_t* sp) {
 623   return next_younger_sp_or_null(valid_sp, sp) != NULL;
 624 }
 625 
 626 bool frame::is_interpreted_frame_valid(JavaThread* thread) const {
 627   assert(is_interpreted_frame(), "Not an interpreted frame");
 628   // These are reasonable sanity checks
 629   if (fp() == 0 || (intptr_t(fp()) & (2*wordSize-1)) != 0) {
 630     return false;
 631   }
 632   if (sp() == 0 || (intptr_t(sp()) & (2*wordSize-1)) != 0) {
 633     return false;
 634   }
 635 
 636   const intptr_t interpreter_frame_initial_sp_offset = interpreter_frame_vm_local_words;
 637   if (fp() + interpreter_frame_initial_sp_offset < sp()) {
 638     return false;
 639   }
 640   // These are hacks to keep us out of trouble.
 641   // The problem with these is that they mask other problems
 642   if (fp() <= sp()) {        // this attempts to deal with unsigned comparison above
 643     return false;
 644   }
 645   // do some validation of frame elements
 646 
 647   // first the method
 648 
 649   Method* m = *interpreter_frame_method_addr();
 650 
 651   // validate the method we'd find in this potential sender
 652   if (!Method::is_valid_method(m)) return false;
 653 
 654   // stack frames shouldn't be much larger than max_stack elements
 655 
 656   if (fp() - unextended_sp() > 1024 + m->max_stack()*Interpreter::stackElementSize) {
 657     return false;
 658   }
 659 
 660   // validate bci/bcp
 661 
 662   address bcp = interpreter_frame_bcp();
 663   if (m->validate_bci_from_bcp(bcp) < 0) {
 664     return false;
 665   }
 666 
 667   // validate ConstantPoolCache*
 668   ConstantPoolCache* cp = *interpreter_frame_cache_addr();
 669   if (MetaspaceObj::is_valid(cp) == false) return false;
 670 
 671   // validate locals
 672 
 673   address locals =  (address) *interpreter_frame_locals_addr();
 674 
 675   if (locals > thread->stack_base() || locals < (address) fp()) return false;
 676 
 677   // We'd have to be pretty unlucky to be mislead at this point
 678   return true;
 679 }
 680 
 681 
 682 // Windows have been flushed on entry (but not marked). Capture the pc that
 683 // is the return address to the frame that contains "sp" as its stack pointer.
 684 // This pc resides in the called of the frame corresponding to "sp".
 685 // As a side effect we mark this JavaFrameAnchor as having flushed the windows.
 686 // This side effect lets us mark stacked JavaFrameAnchors (stacked in the
 687 // call_helper) as flushed when we have flushed the windows for the most
 688 // recent (i.e. current) JavaFrameAnchor. This saves useless flushing calls
 689 // and lets us find the pc just once rather than multiple times as it did
 690 // in the bad old _post_Java_state days.
 691 //
 692 void JavaFrameAnchor::capture_last_Java_pc(intptr_t* sp) {
 693   if (last_Java_sp() != NULL && last_Java_pc() == NULL) {
 694     // try and find the sp just younger than _last_Java_sp
 695     intptr_t* _post_Java_sp = frame::next_younger_sp_or_null(last_Java_sp(), sp);
 696     // Really this should never fail otherwise VM call must have non-standard
 697     // frame linkage (bad) or stack is not properly flushed (worse).
 698     guarantee(_post_Java_sp != NULL, "bad stack!");
 699     _last_Java_pc = (address) _post_Java_sp[ I7->sp_offset_in_saved_window()] + frame::pc_return_offset;
 700 
 701   }
 702   set_window_flushed();
 703 }
 704 
 705 void JavaFrameAnchor::make_walkable(JavaThread* thread) {
 706   if (walkable()) return;
 707   // Eventually make an assert
 708   guarantee(Thread::current() == (Thread*)thread, "only current thread can flush its registers");
 709   // We always flush in case the profiler wants it but we won't mark
 710   // the windows as flushed unless we have a last_Java_frame
 711   intptr_t* sp = StubRoutines::Sparc::flush_callers_register_windows_func()();
 712   if (last_Java_sp() != NULL ) {
 713     capture_last_Java_pc(sp);
 714   }
 715 }
 716 
 717 intptr_t* frame::entry_frame_argument_at(int offset) const {
 718   // convert offset to index to deal with tsi
 719   int index = (Interpreter::expr_offset_in_bytes(offset)/wordSize);
 720 
 721   intptr_t* LSP = (intptr_t*) sp()[Lentry_args->sp_offset_in_saved_window()];
 722   return &LSP[index+1];
 723 }
 724 
 725 
 726 BasicType frame::interpreter_frame_result(oop* oop_result, jvalue* value_result) {
 727   assert(is_interpreted_frame(), "interpreted frame expected");
 728   Method* method = interpreter_frame_method();
 729   BasicType type = method->result_type();
 730 
 731   if (method->is_native()) {
 732     // Prior to notifying the runtime of the method_exit the possible result
 733     // value is saved to l_scratch and d_scratch.
 734 
 735     intptr_t* l_scratch = fp() + interpreter_frame_l_scratch_fp_offset;
 736     intptr_t* d_scratch = fp() + interpreter_frame_d_scratch_fp_offset;
 737 
 738     address l_addr = (address)l_scratch;
 739     // On 64-bit the result for 1/8/16/32-bit result types is in the other
 740     // word half
 741     l_addr += wordSize/2;
 742 
 743     switch (type) {
 744       case T_OBJECT:
 745       case T_ARRAY: {
 746         oop obj = cast_to_oop(at(interpreter_frame_oop_temp_offset));
 747         assert(obj == NULL || Universe::heap()->is_in(obj), "sanity check");
 748         *oop_result = obj;
 749         break;
 750       }
 751 
 752       case T_BOOLEAN : { jint* p = (jint*)l_addr; value_result->z = (jboolean)((*p) & 0x1); break; }
 753       case T_BYTE    : { jint* p = (jint*)l_addr; value_result->b = (jbyte)((*p) & 0xff); break; }
 754       case T_CHAR    : { jint* p = (jint*)l_addr; value_result->c = (jchar)((*p) & 0xffff); break; }
 755       case T_SHORT   : { jint* p = (jint*)l_addr; value_result->s = (jshort)((*p) & 0xffff); break; }
 756       case T_INT     : value_result->i = *(jint*)l_addr; break;
 757       case T_LONG    : value_result->j = *(jlong*)l_scratch; break;
 758       case T_FLOAT   : value_result->f = *(jfloat*)d_scratch; break;
 759       case T_DOUBLE  : value_result->d = *(jdouble*)d_scratch; break;
 760       case T_VOID    : /* Nothing to do */ break;
 761       default        : ShouldNotReachHere();
 762     }
 763   } else {
 764     intptr_t* tos_addr = interpreter_frame_tos_address();
 765 
 766     switch(type) {
 767       case T_OBJECT:
 768       case T_ARRAY: {
 769         oop obj = cast_to_oop(*tos_addr);
 770         assert(obj == NULL || Universe::heap()->is_in(obj), "sanity check");
 771         *oop_result = obj;
 772         break;
 773       }
 774       case T_BOOLEAN : { jint* p = (jint*)tos_addr; value_result->z = (jboolean)((*p) & 0x1); break; }
 775       case T_BYTE    : { jint* p = (jint*)tos_addr; value_result->b = (jbyte)((*p) & 0xff); break; }
 776       case T_CHAR    : { jint* p = (jint*)tos_addr; value_result->c = (jchar)((*p) & 0xffff); break; }
 777       case T_SHORT   : { jint* p = (jint*)tos_addr; value_result->s = (jshort)((*p) & 0xffff); break; }
 778       case T_INT     : value_result->i = *(jint*)tos_addr; break;
 779       case T_LONG    : value_result->j = *(jlong*)tos_addr; break;
 780       case T_FLOAT   : value_result->f = *(jfloat*)tos_addr; break;
 781       case T_DOUBLE  : value_result->d = *(jdouble*)tos_addr; break;
 782       case T_VOID    : /* Nothing to do */ break;
 783       default        : ShouldNotReachHere();
 784     }
 785   };
 786 
 787   return type;
 788 }
 789 
 790 // Lesp pointer is one word lower than the top item on the stack.
 791 intptr_t* frame::interpreter_frame_tos_at(jint offset) const {
 792   int index = (Interpreter::expr_offset_in_bytes(offset)/wordSize) - 1;
 793   return &interpreter_frame_tos_address()[index];
 794 }
 795 
 796 
 797 #ifndef PRODUCT
 798 
 799 #define DESCRIBE_FP_OFFSET(name) \
 800   values.describe(frame_no, fp() + frame::name##_offset, #name)
 801 
 802 void frame::describe_pd(FrameValues& values, int frame_no) {
 803   for (int w = 0; w < frame::register_save_words; w++) {
 804     values.describe(frame_no, sp() + w, err_msg("register save area word %d", w), 1);
 805   }
 806 
 807   if (is_interpreted_frame()) {
 808     DESCRIBE_FP_OFFSET(interpreter_frame_d_scratch_fp);
 809     DESCRIBE_FP_OFFSET(interpreter_frame_l_scratch_fp);
 810     DESCRIBE_FP_OFFSET(interpreter_frame_mirror);
 811     DESCRIBE_FP_OFFSET(interpreter_frame_oop_temp);
 812 
 813     // esp, according to Lesp (e.g. not depending on bci), if seems valid
 814     intptr_t* esp = *interpreter_frame_esp_addr();
 815     if ((esp >= sp()) && (esp < fp())) {
 816       values.describe(-1, esp, "*Lesp");
 817     }
 818   }
 819 
 820   if (!is_compiled_frame()) {
 821     if (frame::callee_aggregate_return_pointer_words != 0) {
 822       values.describe(frame_no, sp() + frame::callee_aggregate_return_pointer_sp_offset, "callee_aggregate_return_pointer_word");
 823     }
 824     for (int w = 0; w < frame::callee_register_argument_save_area_words; w++) {
 825       values.describe(frame_no, sp() + frame::callee_register_argument_save_area_sp_offset + w,
 826                       err_msg("callee_register_argument_save_area_words %d", w));
 827     }
 828   }
 829 }
 830 
 831 #endif
 832 
 833 intptr_t *frame::initial_deoptimization_info() {
 834   // unused... but returns fp() to minimize changes introduced by 7087445
 835   return fp();
 836 }