1 /*
   2  * Copyright 1997-2008 Sun Microsystems, Inc.  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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
  20  * CA 95054 USA or visit www.sun.com if you need additional information or
  21  * have any questions.
  22  *
  23  */
  24 
  25 # include "incls/_precompiled.incl"
  26 # include "incls/_frame_sparc.cpp.incl"
  27 
  28 void RegisterMap::pd_clear() {
  29   if (_thread->has_last_Java_frame()) {
  30     frame fr = _thread->last_frame();
  31     _window = fr.sp();
  32   } else {
  33     _window = NULL;
  34   }
  35   _younger_window = NULL;
  36 }
  37 
  38 
  39 // Unified register numbering scheme: each 32-bits counts as a register
  40 // number, so all the V9 registers take 2 slots.
  41 const static int R_L_nums[] = {0+040,2+040,4+040,6+040,8+040,10+040,12+040,14+040};
  42 const static int R_I_nums[] = {0+060,2+060,4+060,6+060,8+060,10+060,12+060,14+060};
  43 const static int R_O_nums[] = {0+020,2+020,4+020,6+020,8+020,10+020,12+020,14+020};
  44 const static int R_G_nums[] = {0+000,2+000,4+000,6+000,8+000,10+000,12+000,14+000};
  45 static RegisterMap::LocationValidType bad_mask = 0;
  46 static RegisterMap::LocationValidType R_LIO_mask = 0;
  47 static bool register_map_inited = false;
  48 
  49 static void register_map_init() {
  50   if (!register_map_inited) {
  51     register_map_inited = true;
  52     int i;
  53     for (i = 0; i < 8; i++) {
  54       assert(R_L_nums[i] < RegisterMap::location_valid_type_size, "in first chunk");
  55       assert(R_I_nums[i] < RegisterMap::location_valid_type_size, "in first chunk");
  56       assert(R_O_nums[i] < RegisterMap::location_valid_type_size, "in first chunk");
  57       assert(R_G_nums[i] < RegisterMap::location_valid_type_size, "in first chunk");
  58     }
  59 
  60     bad_mask |= (1LL << R_O_nums[6]); // SP
  61     bad_mask |= (1LL << R_O_nums[7]); // cPC
  62     bad_mask |= (1LL << R_I_nums[6]); // FP
  63     bad_mask |= (1LL << R_I_nums[7]); // rPC
  64     bad_mask |= (1LL << R_G_nums[2]); // TLS
  65     bad_mask |= (1LL << R_G_nums[7]); // reserved by libthread
  66 
  67     for (i = 0; i < 8; i++) {
  68       R_LIO_mask |= (1LL << R_L_nums[i]);
  69       R_LIO_mask |= (1LL << R_I_nums[i]);
  70       R_LIO_mask |= (1LL << R_O_nums[i]);
  71     }
  72   }
  73 }
  74 
  75 
  76 address RegisterMap::pd_location(VMReg regname) const {
  77   register_map_init();
  78 
  79   assert(regname->is_reg(), "sanity check");
  80   // Only the GPRs get handled this way
  81   if( !regname->is_Register())
  82     return NULL;
  83 
  84   // don't talk about bad registers
  85   if ((bad_mask & ((LocationValidType)1 << regname->value())) != 0) {
  86     return NULL;
  87   }
  88 
  89   // Convert to a GPR
  90   Register reg;
  91   int second_word = 0;
  92   // 32-bit registers for in, out and local
  93   if (!regname->is_concrete()) {
  94     // HMM ought to return NULL for any non-concrete (odd) vmreg
  95     // this all tied up in the fact we put out double oopMaps for
  96     // register locations. When that is fixed we'd will return NULL
  97     // (or assert here).
  98     reg = regname->prev()->as_Register();
  99 #ifdef _LP64
 100     second_word = sizeof(jint);
 101 #else
 102     return NULL;
 103 #endif // _LP64
 104   } else {
 105     reg = regname->as_Register();
 106   }
 107   if (reg->is_out()) {
 108     assert(_younger_window != NULL, "Younger window should be available");
 109     return second_word + (address)&_younger_window[reg->after_save()->sp_offset_in_saved_window()];
 110   }
 111   if (reg->is_local() || reg->is_in()) {
 112     assert(_window != NULL, "Window should be available");
 113     return second_word + (address)&_window[reg->sp_offset_in_saved_window()];
 114   }
 115   // Only the window'd GPRs get handled this way; not the globals.
 116   return NULL;
 117 }
 118 
 119 
 120 #ifdef ASSERT
 121 void RegisterMap::check_location_valid() {
 122   register_map_init();
 123   assert((_location_valid[0] & bad_mask) == 0, "cannot have special locations for SP,FP,TLS,etc.");
 124 }
 125 #endif
 126 
 127 // We are shifting windows.  That means we are moving all %i to %o,
 128 // getting rid of all current %l, and keeping all %g.  This is only
 129 // complicated if any of the location pointers for these are valid.
 130 // The normal case is that everything is in its standard register window
 131 // home, and _location_valid[0] is zero.  In that case, this routine
 132 // does exactly nothing.
 133 void RegisterMap::shift_individual_registers() {
 134   if (!update_map())  return;  // this only applies to maps with locations
 135   register_map_init();
 136   check_location_valid();
 137 
 138   LocationValidType lv = _location_valid[0];
 139   LocationValidType lv0 = lv;
 140 
 141   lv &= ~R_LIO_mask;  // clear %l, %o, %i regs
 142 
 143   // if we cleared some non-%g locations, we may have to do some shifting
 144   if (lv != lv0) {
 145     // copy %i0-%i5 to %o0-%o5, if they have special locations
 146     // This can happen in within stubs which spill argument registers
 147     // around a dynamic link operation, such as resolve_opt_virtual_call.
 148     for (int i = 0; i < 8; i++) {
 149       if (lv0 & (1LL << R_I_nums[i])) {
 150         _location[R_O_nums[i]] = _location[R_I_nums[i]];
 151         lv |=  (1LL << R_O_nums[i]);
 152       }
 153     }
 154   }
 155 
 156   _location_valid[0] = lv;
 157   check_location_valid();
 158 }
 159 
 160 bool frame::safe_for_sender(JavaThread *thread) {
 161 
 162   address _SP = (address) sp();
 163   address _FP = (address) fp();
 164   address _UNEXTENDED_SP = (address) unextended_sp();
 165   // sp must be within the stack
 166   bool sp_safe = (_SP <= thread->stack_base()) &&
 167                  (_SP >= thread->stack_base() - thread->stack_size());
 168 
 169   if (!sp_safe) {
 170     return false;
 171   }
 172 
 173   // unextended sp must be within the stack and above or equal sp
 174   bool unextended_sp_safe = (_UNEXTENDED_SP <= thread->stack_base()) &&
 175                             (_UNEXTENDED_SP >= _SP);
 176 
 177   if (!unextended_sp_safe) return false;
 178 
 179   // an fp must be within the stack and above (but not equal) sp
 180   bool fp_safe = (_FP <= thread->stack_base()) &&
 181                  (_FP > _SP);
 182 
 183   // We know sp/unextended_sp are safe only fp is questionable here
 184 
 185   // If the current frame is known to the code cache then we can attempt to
 186   // to construct the sender and do some validation of it. This goes a long way
 187   // toward eliminating issues when we get in frame construction code
 188 
 189   if (_cb != NULL ) {
 190 
 191     // First check if frame is complete and tester is reliable
 192     // Unfortunately we can only check frame complete for runtime stubs and nmethod
 193     // other generic buffer blobs are more problematic so we just assume they are
 194     // ok. adapter blobs never have a frame complete and are never ok.
 195 
 196     if (!_cb->is_frame_complete_at(_pc)) {
 197       if (_cb->is_nmethod() || _cb->is_adapter_blob() || _cb->is_runtime_stub()) {
 198         return false;
 199       }
 200     }
 201 
 202     // Entry frame checks
 203     if (is_entry_frame()) {
 204       // an entry frame must have a valid fp.
 205 
 206       if (!fp_safe) {
 207         return false;
 208       }
 209 
 210       // Validate the JavaCallWrapper an entry frame must have
 211 
 212       address jcw = (address)entry_frame_call_wrapper();
 213 
 214       bool jcw_safe = (jcw <= thread->stack_base()) && ( jcw > _FP);
 215 
 216       return jcw_safe;
 217 
 218     }
 219 
 220     intptr_t* younger_sp = sp();
 221     intptr_t* _SENDER_SP = sender_sp(); // sender is actually just _FP
 222     bool adjusted_stack = is_interpreted_frame();
 223 
 224     address   sender_pc = (address)younger_sp[I7->sp_offset_in_saved_window()] + pc_return_offset;
 225 
 226 
 227     // We must always be able to find a recognizable pc
 228     CodeBlob* sender_blob = CodeCache::find_blob_unsafe(sender_pc);
 229     if (sender_pc == NULL ||  sender_blob == NULL) {
 230       return false;
 231     }
 232 
 233     // It should be safe to construct the sender though it might not be valid
 234 
 235     frame sender(_SENDER_SP, younger_sp, adjusted_stack);
 236 
 237     // Do we have a valid fp?
 238     address sender_fp = (address) sender.fp();
 239 
 240     // an fp must be within the stack and above (but not equal) current frame's _FP
 241 
 242     bool sender_fp_safe = (sender_fp <= thread->stack_base()) &&
 243                    (sender_fp > _FP);
 244 
 245     if (!sender_fp_safe) {
 246       return false;
 247     }
 248 
 249 
 250     // If the potential sender is the interpreter then we can do some more checking
 251     if (Interpreter::contains(sender_pc)) {
 252       return sender.is_interpreted_frame_valid(thread);
 253     }
 254 
 255     // Could just be some random pointer within the codeBlob
 256     if (!sender.cb()->instructions_contains(sender_pc)) return false;
 257 
 258     // We should never be able to see an adapter if the current frame is something from code cache
 259 
 260     if ( sender_blob->is_adapter_blob()) {
 261       return false;
 262     }
 263 
 264     if( sender.is_entry_frame()) {
 265       // Validate the JavaCallWrapper an entry frame must have
 266 
 267       address jcw = (address)sender.entry_frame_call_wrapper();
 268 
 269       bool jcw_safe = (jcw <= thread->stack_base()) && ( jcw > sender_fp);
 270 
 271       return jcw_safe;
 272     }
 273 
 274     // If the frame size is 0 something is bad because every nmethod has a non-zero frame size
 275     // because you must allocate window space
 276 
 277     if (sender_blob->frame_size() == 0) {
 278       assert(!sender_blob->is_nmethod(), "should count return address at least");
 279       return false;
 280     }
 281 
 282     // The sender should positively be an nmethod or call_stub. On sparc we might in fact see something else.
 283     // The cause of this is because at a save instruction the O7 we get is a leftover from an earlier
 284     // window use. So if a runtime stub creates two frames (common in fastdebug/jvmg) then we see the
 285     // stale pc. So if the sender blob is not something we'd expect we have little choice but to declare
 286     // the stack unwalkable. pd_get_top_frame_for_signal_handler tries to recover from this by unwinding
 287     // that initial frame and retrying.
 288 
 289     if (!sender_blob->is_nmethod()) {
 290       return false;
 291     }
 292 
 293     // Could put some more validation for the potential non-interpreted sender
 294     // frame we'd create by calling sender if I could think of any. Wait for next crash in forte...
 295 
 296     // One idea is seeing if the sender_pc we have is one that we'd expect to call to current cb
 297 
 298     // We've validated the potential sender that would be created
 299 
 300     return true;
 301 
 302   }
 303 
 304   // Must be native-compiled frame. Since sender will try and use fp to find
 305   // linkages it must be safe
 306 
 307   if (!fp_safe) return false;
 308 
 309   // could try and do some more potential verification of native frame if we could think of some...
 310 
 311   return true;
 312 }
 313 
 314 // constructors
 315 
 316 // Construct an unpatchable, deficient frame
 317 frame::frame(intptr_t* sp, unpatchable_t, address pc, CodeBlob* cb) {
 318 #ifdef _LP64
 319   assert( (((intptr_t)sp & (wordSize-1)) == 0), "frame constructor passed an invalid sp");
 320 #endif
 321   _sp = sp;
 322   _younger_sp = NULL;
 323   _pc = pc;
 324   _cb = cb;
 325   _sp_adjustment_by_callee = 0;
 326   assert(pc == NULL && cb == NULL || pc != NULL, "can't have a cb and no pc!");
 327   if (_cb == NULL && _pc != NULL ) {
 328     _cb = CodeCache::find_blob(_pc);
 329   }
 330   _deopt_state = unknown;
 331 #ifdef ASSERT
 332   if ( _cb != NULL && _cb->is_nmethod()) {
 333     // Without a valid unextended_sp() we can't convert the pc to "original"
 334     assert(!((nmethod*)_cb)->is_deopt_pc(_pc), "invariant broken");
 335   }
 336 #endif // ASSERT
 337 }
 338 
 339 frame::frame(intptr_t* sp, intptr_t* younger_sp, bool younger_frame_adjusted_stack) {
 340   _sp = sp;
 341   _younger_sp = younger_sp;
 342   if (younger_sp == NULL) {
 343     // make a deficient frame which doesn't know where its PC is
 344     _pc = NULL;
 345     _cb = NULL;
 346   } else {
 347     _pc = (address)younger_sp[I7->sp_offset_in_saved_window()] + pc_return_offset;
 348     assert( (intptr_t*)younger_sp[FP->sp_offset_in_saved_window()] == (intptr_t*)((intptr_t)sp - STACK_BIAS), "younger_sp must be valid");
 349     // Any frame we ever build should always "safe" therefore we should not have to call
 350     // find_blob_unsafe
 351     // In case of native stubs, the pc retrieved here might be
 352     // wrong.  (the _last_native_pc will have the right value)
 353     // So do not put add any asserts on the _pc here.
 354   }
 355   if (younger_frame_adjusted_stack) {
 356     // compute adjustment to this frame's SP made by its interpreted callee
 357     _sp_adjustment_by_callee = (intptr_t*)((intptr_t)younger_sp[I5_savedSP->sp_offset_in_saved_window()] +
 358                                              STACK_BIAS) - sp;
 359   } else {
 360     _sp_adjustment_by_callee = 0;
 361   }
 362 
 363   _deopt_state = unknown;
 364 
 365   // It is important that frame be fully construct when we do this lookup
 366   // as get_original_pc() needs correct value for unextended_sp()
 367   if (_pc != NULL) {
 368     _cb = CodeCache::find_blob(_pc);
 369     if (_cb != NULL && _cb->is_nmethod() && ((nmethod*)_cb)->is_deopt_pc(_pc)) {
 370       _pc = ((nmethod*)_cb)->get_original_pc(this);
 371       _deopt_state = is_deoptimized;
 372     } else {
 373       _deopt_state = not_deoptimized;
 374     }
 375   }
 376 }
 377 
 378 bool frame::is_interpreted_frame() const  {
 379   return Interpreter::contains(pc());
 380 }
 381 
 382 // sender_sp
 383 
 384 intptr_t* frame::interpreter_frame_sender_sp() const {
 385   assert(is_interpreted_frame(), "interpreted frame expected");
 386   return fp();
 387 }
 388 
 389 #ifndef CC_INTERP
 390 void frame::set_interpreter_frame_sender_sp(intptr_t* sender_sp) {
 391   assert(is_interpreted_frame(), "interpreted frame expected");
 392   Unimplemented();
 393 }
 394 #endif // CC_INTERP
 395 
 396 
 397 #ifdef ASSERT
 398 // Debugging aid
 399 static frame nth_sender(int n) {
 400   frame f = JavaThread::current()->last_frame();
 401 
 402   for(int i = 0; i < n; ++i)
 403     f = f.sender((RegisterMap*)NULL);
 404 
 405   printf("first frame %d\n",          f.is_first_frame()       ? 1 : 0);
 406   printf("interpreted frame %d\n",    f.is_interpreted_frame() ? 1 : 0);
 407   printf("java frame %d\n",           f.is_java_frame()        ? 1 : 0);
 408   printf("entry frame %d\n",          f.is_entry_frame()       ? 1 : 0);
 409   printf("native frame %d\n",         f.is_native_frame()      ? 1 : 0);
 410   if (f.is_compiled_frame()) {
 411     if (f.is_deoptimized_frame())
 412       printf("deoptimized frame 1\n");
 413     else
 414       printf("compiled frame 1\n");
 415   }
 416 
 417   return f;
 418 }
 419 #endif
 420 
 421 
 422 frame frame::sender_for_entry_frame(RegisterMap *map) const {
 423   assert(map != NULL, "map must be set");
 424   // Java frame called from C; skip all C frames and return top C
 425   // frame of that chunk as the sender
 426   JavaFrameAnchor* jfa = entry_frame_call_wrapper()->anchor();
 427   assert(!entry_frame_is_first(), "next Java fp must be non zero");
 428   assert(jfa->last_Java_sp() > _sp, "must be above this frame on stack");
 429   intptr_t* last_Java_sp = jfa->last_Java_sp();
 430   // Since we are walking the stack now this nested anchor is obviously walkable
 431   // even if it wasn't when it was stacked.
 432   if (!jfa->walkable()) {
 433     // Capture _last_Java_pc (if needed) and mark anchor walkable.
 434     jfa->capture_last_Java_pc(_sp);
 435   }
 436   assert(jfa->last_Java_pc() != NULL, "No captured pc!");
 437   map->clear();
 438   map->make_integer_regs_unsaved();
 439   map->shift_window(last_Java_sp, NULL);
 440   assert(map->include_argument_oops(), "should be set by clear");
 441   return frame(last_Java_sp, frame::unpatchable, jfa->last_Java_pc());
 442 }
 443 
 444 frame frame::sender_for_interpreter_frame(RegisterMap *map) const {
 445   ShouldNotCallThis();
 446   return sender(map);
 447 }
 448 
 449 frame frame::sender_for_compiled_frame(RegisterMap *map) const {
 450   ShouldNotCallThis();
 451   return sender(map);
 452 }
 453 
 454 frame frame::sender(RegisterMap* map) const {
 455   assert(map != NULL, "map must be set");
 456 
 457   assert(CodeCache::find_blob_unsafe(_pc) == _cb, "inconsistent");
 458 
 459   // Default is not to follow arguments; update it accordingly below
 460   map->set_include_argument_oops(false);
 461 
 462   if (is_entry_frame()) return sender_for_entry_frame(map);
 463 
 464   intptr_t* younger_sp     = sp();
 465   intptr_t* sp             = sender_sp();
 466   bool      adjusted_stack = false;
 467 
 468   // Note:  The version of this operation on any platform with callee-save
 469   //        registers must update the register map (if not null).
 470   //        In order to do this correctly, the various subtypes of
 471   //        of frame (interpreted, compiled, glue, native),
 472   //        must be distinguished.  There is no need on SPARC for
 473   //        such distinctions, because all callee-save registers are
 474   //        preserved for all frames via SPARC-specific mechanisms.
 475   //
 476   //        *** HOWEVER, *** if and when we make any floating-point
 477   //        registers callee-saved, then we will have to copy over
 478   //        the RegisterMap update logic from the Intel code.
 479 
 480   // The constructor of the sender must know whether this frame is interpreted so it can set the
 481   // sender's _sp_adjustment_by_callee field.  An osr adapter frame was originally
 482   // interpreted but its pc is in the code cache (for c1 -> osr_frame_return_id stub), so it must be
 483   // explicitly recognized.
 484 
 485   adjusted_stack = is_interpreted_frame();
 486   if (adjusted_stack) {
 487     map->make_integer_regs_unsaved();
 488     map->shift_window(sp, younger_sp);
 489   } else if (_cb != NULL) {
 490     // Update the locations of implicitly saved registers to be their
 491     // addresses in the register save area.
 492     // For %o registers, the addresses of %i registers in the next younger
 493     // frame are used.
 494     map->shift_window(sp, younger_sp);
 495     if (map->update_map()) {
 496       // Tell GC to use argument oopmaps for some runtime stubs that need it.
 497       // For C1, the runtime stub might not have oop maps, so set this flag
 498       // outside of update_register_map.
 499       map->set_include_argument_oops(_cb->caller_must_gc_arguments(map->thread()));
 500       if (_cb->oop_maps() != NULL) {
 501         OopMapSet::update_register_map(this, map);
 502       }
 503     }
 504   }
 505   return frame(sp, younger_sp, adjusted_stack);
 506 }
 507 
 508 
 509 void frame::patch_pc(Thread* thread, address pc) {
 510   if(thread == Thread::current()) {
 511    StubRoutines::Sparc::flush_callers_register_windows_func()();
 512   }
 513   if (TracePcPatching) {
 514     // QQQ this assert is invalid (or too strong anyway) sice _pc could
 515     // be original pc and frame could have the deopt pc.
 516     // assert(_pc == *O7_addr() + pc_return_offset, "frame has wrong pc");
 517     tty->print_cr("patch_pc at address  0x%x [0x%x -> 0x%x] ", O7_addr(), _pc, pc);
 518   }
 519   _cb = CodeCache::find_blob(pc);
 520   *O7_addr() = pc - pc_return_offset;
 521   _cb = CodeCache::find_blob(_pc);
 522   if (_cb != NULL && _cb->is_nmethod() && ((nmethod*)_cb)->is_deopt_pc(_pc)) {
 523     address orig = ((nmethod*)_cb)->get_original_pc(this);
 524     assert(orig == _pc, "expected original to be stored before patching");
 525     _deopt_state = is_deoptimized;
 526   } else {
 527     _deopt_state = not_deoptimized;
 528   }
 529 }
 530 
 531 
 532 static bool sp_is_valid(intptr_t* old_sp, intptr_t* young_sp, intptr_t* sp) {
 533   return (((intptr_t)sp & (2*wordSize-1)) == 0 &&
 534           sp <= old_sp &&
 535           sp >= young_sp);
 536 }
 537 
 538 
 539 /*
 540   Find the (biased) sp that is just younger than old_sp starting at sp.
 541   If not found return NULL. Register windows are assumed to be flushed.
 542 */
 543 intptr_t* frame::next_younger_sp_or_null(intptr_t* old_sp, intptr_t* sp) {
 544 
 545   intptr_t* previous_sp = NULL;
 546   intptr_t* orig_sp = sp;
 547 
 548   int max_frames = (old_sp - sp) / 16; // Minimum frame size is 16
 549   int max_frame2 = max_frames;
 550   while(sp != old_sp && sp_is_valid(old_sp, orig_sp, sp)) {
 551     if (max_frames-- <= 0)
 552       // too many frames have gone by; invalid parameters given to this function
 553       break;
 554     previous_sp = sp;
 555     sp = (intptr_t*)sp[FP->sp_offset_in_saved_window()];
 556     sp = (intptr_t*)((intptr_t)sp + STACK_BIAS);
 557   }
 558 
 559   return (sp == old_sp ? previous_sp : NULL);
 560 }
 561 
 562 /*
 563   Determine if "sp" is a valid stack pointer. "sp" is assumed to be younger than
 564   "valid_sp". So if "sp" is valid itself then it should be possible to walk frames
 565   from "sp" to "valid_sp". The assumption is that the registers windows for the
 566   thread stack in question are flushed.
 567 */
 568 bool frame::is_valid_stack_pointer(intptr_t* valid_sp, intptr_t* sp) {
 569   return next_younger_sp_or_null(valid_sp, sp) != NULL;
 570 }
 571 
 572 
 573 bool frame::interpreter_frame_equals_unpacked_fp(intptr_t* fp) {
 574   assert(is_interpreted_frame(), "must be interpreter frame");
 575   return this->fp() == fp;
 576 }
 577 
 578 
 579 void frame::pd_gc_epilog() {
 580   if (is_interpreted_frame()) {
 581     // set constant pool cache entry for interpreter
 582     methodOop m = interpreter_frame_method();
 583 
 584     *interpreter_frame_cpoolcache_addr() = m->constants()->cache();
 585   }
 586 }
 587 
 588 
 589 bool frame::is_interpreted_frame_valid(JavaThread* thread) const {
 590 #ifdef CC_INTERP
 591   // Is there anything to do?
 592 #else
 593   assert(is_interpreted_frame(), "Not an interpreted frame");
 594   // These are reasonable sanity checks
 595   if (fp() == 0 || (intptr_t(fp()) & (2*wordSize-1)) != 0) {
 596     return false;
 597   }
 598   if (sp() == 0 || (intptr_t(sp()) & (2*wordSize-1)) != 0) {
 599     return false;
 600   }
 601 
 602   const intptr_t interpreter_frame_initial_sp_offset = interpreter_frame_vm_local_words;
 603   if (fp() + interpreter_frame_initial_sp_offset < sp()) {
 604     return false;
 605   }
 606   // These are hacks to keep us out of trouble.
 607   // The problem with these is that they mask other problems
 608   if (fp() <= sp()) {        // this attempts to deal with unsigned comparison above
 609     return false;
 610   }
 611   // do some validation of frame elements
 612 
 613   // first the method
 614 
 615   methodOop m = *interpreter_frame_method_addr();
 616 
 617   // validate the method we'd find in this potential sender
 618   if (!Universe::heap()->is_valid_method(m)) return false;
 619 
 620   // stack frames shouldn't be much larger than max_stack elements
 621 
 622   if (fp() - sp() > 1024 + m->max_stack()*Interpreter::stackElementSize()) {
 623     return false;
 624   }
 625 
 626   // validate bci/bcx
 627 
 628   intptr_t  bcx    = interpreter_frame_bcx();
 629   if (m->validate_bci_from_bcx(bcx) < 0) {
 630     return false;
 631   }
 632 
 633   // validate constantPoolCacheOop
 634 
 635   constantPoolCacheOop cp = *interpreter_frame_cache_addr();
 636 
 637   if (cp == NULL ||
 638       !Space::is_aligned(cp) ||
 639       !Universe::heap()->is_permanent((void*)cp)) return false;
 640 
 641   // validate locals
 642 
 643   address locals =  (address) *interpreter_frame_locals_addr();
 644 
 645   if (locals > thread->stack_base() || locals < (address) fp()) return false;
 646 
 647   // We'd have to be pretty unlucky to be mislead at this point
 648 #endif /* CC_INTERP */
 649   return true;
 650 }
 651 
 652 
 653 // Windows have been flushed on entry (but not marked). Capture the pc that
 654 // is the return address to the frame that contains "sp" as its stack pointer.
 655 // This pc resides in the called of the frame corresponding to "sp".
 656 // As a side effect we mark this JavaFrameAnchor as having flushed the windows.
 657 // This side effect lets us mark stacked JavaFrameAnchors (stacked in the
 658 // call_helper) as flushed when we have flushed the windows for the most
 659 // recent (i.e. current) JavaFrameAnchor. This saves useless flushing calls
 660 // and lets us find the pc just once rather than multiple times as it did
 661 // in the bad old _post_Java_state days.
 662 //
 663 void JavaFrameAnchor::capture_last_Java_pc(intptr_t* sp) {
 664   if (last_Java_sp() != NULL && last_Java_pc() == NULL) {
 665     // try and find the sp just younger than _last_Java_sp
 666     intptr_t* _post_Java_sp = frame::next_younger_sp_or_null(last_Java_sp(), sp);
 667     // Really this should never fail otherwise VM call must have non-standard
 668     // frame linkage (bad) or stack is not properly flushed (worse).
 669     guarantee(_post_Java_sp != NULL, "bad stack!");
 670     _last_Java_pc = (address) _post_Java_sp[ I7->sp_offset_in_saved_window()] + frame::pc_return_offset;
 671 
 672   }
 673   set_window_flushed();
 674 }
 675 
 676 void JavaFrameAnchor::make_walkable(JavaThread* thread) {
 677   if (walkable()) return;
 678   // Eventually make an assert
 679   guarantee(Thread::current() == (Thread*)thread, "only current thread can flush its registers");
 680   // We always flush in case the profiler wants it but we won't mark
 681   // the windows as flushed unless we have a last_Java_frame
 682   intptr_t* sp = StubRoutines::Sparc::flush_callers_register_windows_func()();
 683   if (last_Java_sp() != NULL ) {
 684     capture_last_Java_pc(sp);
 685   }
 686 }
 687 
 688 intptr_t* frame::entry_frame_argument_at(int offset) const {
 689   // convert offset to index to deal with tsi
 690   int index = (Interpreter::expr_offset_in_bytes(offset)/wordSize);
 691 
 692   intptr_t* LSP = (intptr_t*) sp()[Lentry_args->sp_offset_in_saved_window()];
 693   return &LSP[index+1];
 694 }
 695 
 696 
 697 BasicType frame::interpreter_frame_result(oop* oop_result, jvalue* value_result) {
 698   assert(is_interpreted_frame(), "interpreted frame expected");
 699   methodOop method = interpreter_frame_method();
 700   BasicType type = method->result_type();
 701 
 702   if (method->is_native()) {
 703     // Prior to notifying the runtime of the method_exit the possible result
 704     // value is saved to l_scratch and d_scratch.
 705 
 706 #ifdef CC_INTERP
 707     interpreterState istate = get_interpreterState();
 708     intptr_t* l_scratch = (intptr_t*) &istate->_native_lresult;
 709     intptr_t* d_scratch = (intptr_t*) &istate->_native_fresult;
 710 #else /* CC_INTERP */
 711     intptr_t* l_scratch = fp() + interpreter_frame_l_scratch_fp_offset;
 712     intptr_t* d_scratch = fp() + interpreter_frame_d_scratch_fp_offset;
 713 #endif /* CC_INTERP */
 714 
 715     address l_addr = (address)l_scratch;
 716 #ifdef _LP64
 717     // On 64-bit the result for 1/8/16/32-bit result types is in the other
 718     // word half
 719     l_addr += wordSize/2;
 720 #endif
 721 
 722     switch (type) {
 723       case T_OBJECT:
 724       case T_ARRAY: {
 725 #ifdef CC_INTERP
 726         *oop_result = istate->_oop_temp;
 727 #else
 728         oop obj = (oop) at(interpreter_frame_oop_temp_offset);
 729         assert(obj == NULL || Universe::heap()->is_in(obj), "sanity check");
 730         *oop_result = obj;
 731 #endif // CC_INTERP
 732         break;
 733       }
 734 
 735       case T_BOOLEAN : { jint* p = (jint*)l_addr; value_result->z = (jboolean)((*p) & 0x1); break; }
 736       case T_BYTE    : { jint* p = (jint*)l_addr; value_result->b = (jbyte)((*p) & 0xff); break; }
 737       case T_CHAR    : { jint* p = (jint*)l_addr; value_result->c = (jchar)((*p) & 0xffff); break; }
 738       case T_SHORT   : { jint* p = (jint*)l_addr; value_result->s = (jshort)((*p) & 0xffff); break; }
 739       case T_INT     : value_result->i = *(jint*)l_addr; break;
 740       case T_LONG    : value_result->j = *(jlong*)l_scratch; break;
 741       case T_FLOAT   : value_result->f = *(jfloat*)d_scratch; break;
 742       case T_DOUBLE  : value_result->d = *(jdouble*)d_scratch; break;
 743       case T_VOID    : /* Nothing to do */ break;
 744       default        : ShouldNotReachHere();
 745     }
 746   } else {
 747     intptr_t* tos_addr = interpreter_frame_tos_address();
 748 
 749     switch(type) {
 750       case T_OBJECT:
 751       case T_ARRAY: {
 752         oop obj = (oop)*tos_addr;
 753         assert(obj == NULL || Universe::heap()->is_in(obj), "sanity check");
 754         *oop_result = obj;
 755         break;
 756       }
 757       case T_BOOLEAN : { jint* p = (jint*)tos_addr; value_result->z = (jboolean)((*p) & 0x1); break; }
 758       case T_BYTE    : { jint* p = (jint*)tos_addr; value_result->b = (jbyte)((*p) & 0xff); break; }
 759       case T_CHAR    : { jint* p = (jint*)tos_addr; value_result->c = (jchar)((*p) & 0xffff); break; }
 760       case T_SHORT   : { jint* p = (jint*)tos_addr; value_result->s = (jshort)((*p) & 0xffff); break; }
 761       case T_INT     : value_result->i = *(jint*)tos_addr; break;
 762       case T_LONG    : value_result->j = *(jlong*)tos_addr; break;
 763       case T_FLOAT   : value_result->f = *(jfloat*)tos_addr; break;
 764       case T_DOUBLE  : value_result->d = *(jdouble*)tos_addr; break;
 765       case T_VOID    : /* Nothing to do */ break;
 766       default        : ShouldNotReachHere();
 767     }
 768   };
 769 
 770   return type;
 771 }
 772 
 773 // Lesp pointer is one word lower than the top item on the stack.
 774 intptr_t* frame::interpreter_frame_tos_at(jint offset) const {
 775   int index = (Interpreter::expr_offset_in_bytes(offset)/wordSize) - 1;
 776   return &interpreter_frame_tos_address()[index];
 777 }