1 /* 2 * Copyright 1997-2009 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_x86.cpp.incl" 27 28 #ifdef ASSERT 29 void RegisterMap::check_location_valid() { 30 } 31 #endif 32 33 34 // Profiling/safepoint support 35 36 bool frame::safe_for_sender(JavaThread *thread) { 37 address sp = (address)_sp; 38 address fp = (address)_fp; 39 address unextended_sp = (address)_unextended_sp; 40 // sp must be within the stack 41 bool sp_safe = (sp <= thread->stack_base()) && 42 (sp >= thread->stack_base() - thread->stack_size()); 43 44 if (!sp_safe) { 45 return false; 46 } 47 48 // unextended sp must be within the stack and above or equal sp 49 bool unextended_sp_safe = (unextended_sp <= thread->stack_base()) && 50 (unextended_sp >= sp); 51 52 if (!unextended_sp_safe) { 53 return false; 54 } 55 56 // an fp must be within the stack and above (but not equal) sp 57 bool fp_safe = (fp <= thread->stack_base()) && (fp > sp); 58 59 // We know sp/unextended_sp are safe only fp is questionable here 60 61 // If the current frame is known to the code cache then we can attempt to 62 // to construct the sender and do some validation of it. This goes a long way 63 // toward eliminating issues when we get in frame construction code 64 65 if (_cb != NULL ) { 66 67 // First check if frame is complete and tester is reliable 68 // Unfortunately we can only check frame complete for runtime stubs and nmethod 69 // other generic buffer blobs are more problematic so we just assume they are 70 // ok. adapter blobs never have a frame complete and are never ok. 71 72 if (!_cb->is_frame_complete_at(_pc)) { 73 if (_cb->is_nmethod() || _cb->is_adapter_blob() || _cb->is_runtime_stub()) { 74 return false; 75 } 76 } 77 // Entry frame checks 78 if (is_entry_frame()) { 79 // an entry frame must have a valid fp. 80 81 if (!fp_safe) return false; 82 83 // Validate the JavaCallWrapper an entry frame must have 84 85 address jcw = (address)entry_frame_call_wrapper(); 86 87 bool jcw_safe = (jcw <= thread->stack_base()) && ( jcw > fp); 88 89 return jcw_safe; 90 91 } 92 93 intptr_t* sender_sp = NULL; 94 address sender_pc = NULL; 95 96 if (is_interpreted_frame()) { 97 // fp must be safe 98 if (!fp_safe) { 99 return false; 100 } 101 102 sender_pc = (address) this->fp()[return_addr_offset]; 103 sender_sp = (intptr_t*) addr_at(sender_sp_offset); 104 105 } else { 106 // must be some sort of compiled/runtime frame 107 // fp does not have to be safe (although it could be check for c1?) 108 109 sender_sp = _unextended_sp + _cb->frame_size(); 110 // On Intel the return_address is always the word on the stack 111 sender_pc = (address) *(sender_sp-1); 112 } 113 114 // We must always be able to find a recognizable pc 115 CodeBlob* sender_blob = CodeCache::find_blob_unsafe(sender_pc); 116 if (sender_pc == NULL || sender_blob == NULL) { 117 return false; 118 } 119 120 121 // If the potential sender is the interpreter then we can do some more checking 122 if (Interpreter::contains(sender_pc)) { 123 124 // ebp is always saved in a recognizable place in any code we generate. However 125 // only if the sender is interpreted/call_stub (c1 too?) are we certain that the saved ebp 126 // is really a frame pointer. 127 128 intptr_t *saved_fp = (intptr_t*)*(sender_sp - frame::sender_sp_offset); 129 bool saved_fp_safe = ((address)saved_fp <= thread->stack_base()) && (saved_fp > sender_sp); 130 131 if (!saved_fp_safe) { 132 return false; 133 } 134 135 // construct the potential sender 136 137 frame sender(sender_sp, saved_fp, sender_pc); 138 139 return sender.is_interpreted_frame_valid(thread); 140 141 } 142 143 // Could just be some random pointer within the codeBlob 144 145 if (!sender_blob->instructions_contains(sender_pc)) return false; 146 147 // We should never be able to see an adapter if the current frame is something from code cache 148 149 if ( sender_blob->is_adapter_blob()) { 150 return false; 151 } 152 153 // Could be the call_stub 154 155 if (StubRoutines::returns_to_call_stub(sender_pc)) { 156 intptr_t *saved_fp = (intptr_t*)*(sender_sp - frame::sender_sp_offset); 157 bool saved_fp_safe = ((address)saved_fp <= thread->stack_base()) && (saved_fp > sender_sp); 158 159 if (!saved_fp_safe) { 160 return false; 161 } 162 163 // construct the potential sender 164 165 frame sender(sender_sp, saved_fp, sender_pc); 166 167 // Validate the JavaCallWrapper an entry frame must have 168 address jcw = (address)sender.entry_frame_call_wrapper(); 169 170 bool jcw_safe = (jcw <= thread->stack_base()) && ( jcw > (address)sender.fp()); 171 172 return jcw_safe; 173 } 174 175 // If the frame size is 0 something is bad because every nmethod has a non-zero frame size 176 // because the return address counts against the callee's frame. 177 178 if (sender_blob->frame_size() == 0) { 179 assert(!sender_blob->is_nmethod(), "should count return address at least"); 180 return false; 181 } 182 183 // We should never be able to see anything here except an nmethod. If something in the 184 // code cache (current frame) is called by an entity within the code cache that entity 185 // should not be anything but the call stub (already covered), the interpreter (already covered) 186 // or an nmethod. 187 188 assert(sender_blob->is_nmethod(), "Impossible call chain"); 189 190 // Could put some more validation for the potential non-interpreted sender 191 // frame we'd create by calling sender if I could think of any. Wait for next crash in forte... 192 193 // One idea is seeing if the sender_pc we have is one that we'd expect to call to current cb 194 195 // We've validated the potential sender that would be created 196 return true; 197 } 198 199 // Must be native-compiled frame. Since sender will try and use fp to find 200 // linkages it must be safe 201 202 if (!fp_safe) { 203 return false; 204 } 205 206 // Will the pc we fetch be non-zero (which we'll find at the oldest frame) 207 208 if ( (address) this->fp()[return_addr_offset] == NULL) return false; 209 210 211 // could try and do some more potential verification of native frame if we could think of some... 212 213 return true; 214 215 } 216 217 218 void frame::patch_pc(Thread* thread, address pc) { 219 if (TracePcPatching) { 220 tty->print_cr("patch_pc at address" INTPTR_FORMAT " [" INTPTR_FORMAT " -> " INTPTR_FORMAT "] ", 221 &((address *)sp())[-1], ((address *)sp())[-1], pc); 222 } 223 ((address *)sp())[-1] = pc; 224 _cb = CodeCache::find_blob(pc); 225 if (_cb != NULL && _cb->is_nmethod() && ((nmethod*)_cb)->is_deopt_pc(_pc)) { 226 address orig = (((nmethod*)_cb)->get_original_pc(this)); 227 assert(orig == _pc, "expected original to be stored before patching"); 228 _deopt_state = is_deoptimized; 229 // leave _pc as is 230 } else { 231 _deopt_state = not_deoptimized; 232 _pc = pc; 233 } 234 } 235 236 bool frame::is_interpreted_frame() const { 237 return Interpreter::contains(pc()); 238 } 239 240 int frame::frame_size(RegisterMap* map) const { 241 frame sender = this->sender(map); 242 return sender.sp() - sp(); 243 } 244 245 intptr_t* frame::entry_frame_argument_at(int offset) const { 246 // convert offset to index to deal with tsi 247 int index = (Interpreter::expr_offset_in_bytes(offset)/wordSize); 248 // Entry frame's arguments are always in relation to unextended_sp() 249 return &unextended_sp()[index]; 250 } 251 252 // sender_sp 253 #ifdef CC_INTERP 254 intptr_t* frame::interpreter_frame_sender_sp() const { 255 assert(is_interpreted_frame(), "interpreted frame expected"); 256 // QQQ why does this specialize method exist if frame::sender_sp() does same thing? 257 // seems odd and if we always know interpreted vs. non then sender_sp() is really 258 // doing too much work. 259 return get_interpreterState()->sender_sp(); 260 } 261 262 // monitor elements 263 264 BasicObjectLock* frame::interpreter_frame_monitor_begin() const { 265 return get_interpreterState()->monitor_base(); 266 } 267 268 BasicObjectLock* frame::interpreter_frame_monitor_end() const { 269 return (BasicObjectLock*) get_interpreterState()->stack_base(); 270 } 271 272 #else // CC_INTERP 273 274 intptr_t* frame::interpreter_frame_sender_sp() const { 275 assert(is_interpreted_frame(), "interpreted frame expected"); 276 return (intptr_t*) at(interpreter_frame_sender_sp_offset); 277 } 278 279 void frame::set_interpreter_frame_sender_sp(intptr_t* sender_sp) { 280 assert(is_interpreted_frame(), "interpreted frame expected"); 281 ptr_at_put(interpreter_frame_sender_sp_offset, (intptr_t) sender_sp); 282 } 283 284 285 // monitor elements 286 287 BasicObjectLock* frame::interpreter_frame_monitor_begin() const { 288 return (BasicObjectLock*) addr_at(interpreter_frame_monitor_block_bottom_offset); 289 } 290 291 BasicObjectLock* frame::interpreter_frame_monitor_end() const { 292 BasicObjectLock* result = (BasicObjectLock*) *addr_at(interpreter_frame_monitor_block_top_offset); 293 // make sure the pointer points inside the frame 294 assert((intptr_t) fp() > (intptr_t) result, "result must < than frame pointer"); 295 assert((intptr_t) sp() <= (intptr_t) result, "result must >= than stack pointer"); 296 return result; 297 } 298 299 void frame::interpreter_frame_set_monitor_end(BasicObjectLock* value) { 300 *((BasicObjectLock**)addr_at(interpreter_frame_monitor_block_top_offset)) = value; 301 } 302 303 // Used by template based interpreter deoptimization 304 void frame::interpreter_frame_set_last_sp(intptr_t* sp) { 305 *((intptr_t**)addr_at(interpreter_frame_last_sp_offset)) = sp; 306 } 307 #endif // CC_INTERP 308 309 frame frame::sender_for_entry_frame(RegisterMap* map) const { 310 assert(map != NULL, "map must be set"); 311 // Java frame called from C; skip all C frames and return top C 312 // frame of that chunk as the sender 313 JavaFrameAnchor* jfa = entry_frame_call_wrapper()->anchor(); 314 assert(!entry_frame_is_first(), "next Java fp must be non zero"); 315 assert(jfa->last_Java_sp() > sp(), "must be above this frame on stack"); 316 map->clear(); 317 assert(map->include_argument_oops(), "should be set by clear"); 318 if (jfa->last_Java_pc() != NULL ) { 319 frame fr(jfa->last_Java_sp(), jfa->last_Java_fp(), jfa->last_Java_pc()); 320 return fr; 321 } 322 frame fr(jfa->last_Java_sp(), jfa->last_Java_fp()); 323 return fr; 324 } 325 326 frame frame::sender_for_interpreter_frame(RegisterMap* map) const { 327 // sp is the raw sp from the sender after adapter or interpreter extension 328 intptr_t* sp = (intptr_t*) addr_at(sender_sp_offset); 329 330 // This is the sp before any possible extension (adapter/locals). 331 intptr_t* unextended_sp = interpreter_frame_sender_sp(); 332 333 address sender_pc = this->sender_pc(); 334 CodeBlob* sender_cb = CodeCache::find_blob_unsafe(sender_pc); 335 assert(sender_cb, "sanity"); 336 nmethod* sender_nm = sender_cb->as_nmethod_or_null(); 337 if (sender_nm != NULL && sender_nm->is_method_handle_return(sender_pc)) { 338 unextended_sp = (intptr_t*) at(link_offset); 339 } 340 341 // The interpreter and compiler(s) always save EBP/RBP in a known 342 // location on entry. We must record where that location is 343 // so this if EBP/RBP was live on callout from c2 we can find 344 // the saved copy no matter what it called. 345 346 // Since the interpreter always saves EBP/RBP if we record where it is then 347 // we don't have to always save EBP/RBP on entry and exit to c2 compiled 348 // code, on entry will be enough. 349 #ifdef COMPILER2 350 if (map->update_map()) { 351 map->set_location(rbp->as_VMReg(), (address) addr_at(link_offset)); 352 #ifdef AMD64 353 // this is weird "H" ought to be at a higher address however the 354 // oopMaps seems to have the "H" regs at the same address and the 355 // vanilla register. 356 // XXXX make this go away 357 if (true) { 358 map->set_location(rbp->as_VMReg()->next(), (address)addr_at(link_offset)); 359 } 360 #endif // AMD64 361 } 362 #endif /* COMPILER2 */ 363 return frame(sp, unextended_sp, link(), sender_pc); 364 } 365 366 367 //------------------------------sender_for_compiled_frame----------------------- 368 frame frame::sender_for_compiled_frame(RegisterMap* map) const { 369 assert(map != NULL, "map must be set"); 370 const bool c1_compiled = _cb->is_compiled_by_c1(); 371 372 // frame owned by optimizing compiler 373 intptr_t* sender_sp = NULL; 374 375 assert(_cb->frame_size() >= 0, "must have non-zero frame size"); 376 sender_sp = unextended_sp() + _cb->frame_size(); 377 378 // On Intel the return_address is always the word on the stack 379 address sender_pc = (address) *(sender_sp-1); 380 381 // This is the saved value of ebp which may or may not really be an fp. 382 // it is only an fp if the sender is an interpreter frame (or c1?) 383 384 intptr_t *saved_fp = (intptr_t*)*(sender_sp - frame::sender_sp_offset); 385 386 intptr_t* unextended_sp = sender_sp; 387 // If we are returning to a compiled method handle call site, 388 // the saved_fp will in fact be a saved value of the unextended SP. 389 // The simplest way to tell whether we are returning to such a call 390 // site is as follows: 391 CodeBlob* sender_cb = CodeCache::find_blob_unsafe(sender_pc); 392 assert(sender_cb, "sanity"); 393 nmethod* sender_nm = sender_cb->as_nmethod_or_null(); 394 if (sender_nm != NULL && sender_nm->is_method_handle_return(sender_pc)) { 395 unextended_sp = saved_fp; 396 } 397 398 if (map->update_map()) { 399 // Tell GC to use argument oopmaps for some runtime stubs that need it. 400 // For C1, the runtime stub might not have oop maps, so set this flag 401 // outside of update_register_map. 402 map->set_include_argument_oops(_cb->caller_must_gc_arguments(map->thread())); 403 if (_cb->oop_maps() != NULL) { 404 OopMapSet::update_register_map(this, map); 405 } 406 // Since the prolog does the save and restore of epb there is no oopmap 407 // for it so we must fill in its location as if there was an oopmap entry 408 // since if our caller was compiled code there could be live jvm state in it. 409 map->set_location(rbp->as_VMReg(), (address) (sender_sp - frame::sender_sp_offset)); 410 #ifdef AMD64 411 // this is weird "H" ought to be at a higher address however the 412 // oopMaps seems to have the "H" regs at the same address and the 413 // vanilla register. 414 // XXXX make this go away 415 if (true) { 416 map->set_location(rbp->as_VMReg()->next(), (address) (sender_sp - frame::sender_sp_offset)); 417 } 418 #endif // AMD64 419 } 420 421 assert(sender_sp != sp(), "must have changed"); 422 return frame(sender_sp, unextended_sp, saved_fp, sender_pc); 423 } 424 425 frame frame::sender(RegisterMap* map) const { 426 // Default is we done have to follow them. The sender_for_xxx will 427 // update it accordingly 428 map->set_include_argument_oops(false); 429 430 if (is_entry_frame()) return sender_for_entry_frame(map); 431 if (is_interpreted_frame()) return sender_for_interpreter_frame(map); 432 assert(_cb == CodeCache::find_blob(pc()),"Must be the same"); 433 434 if (_cb != NULL) { 435 return sender_for_compiled_frame(map); 436 } 437 // Must be native-compiled frame, i.e. the marshaling code for native 438 // methods that exists in the core system. 439 return frame(sender_sp(), link(), sender_pc()); 440 } 441 442 443 bool frame::interpreter_frame_equals_unpacked_fp(intptr_t* fp) { 444 assert(is_interpreted_frame(), "must be interpreter frame"); 445 methodOop method = interpreter_frame_method(); 446 // When unpacking an optimized frame the frame pointer is 447 // adjusted with: 448 int diff = (method->max_locals() - method->size_of_parameters()) * 449 Interpreter::stackElementWords(); 450 return _fp == (fp - diff); 451 } 452 453 void frame::pd_gc_epilog() { 454 // nothing done here now 455 } 456 457 bool frame::is_interpreted_frame_valid(JavaThread* thread) const { 458 // QQQ 459 #ifdef CC_INTERP 460 #else 461 assert(is_interpreted_frame(), "Not an interpreted frame"); 462 // These are reasonable sanity checks 463 if (fp() == 0 || (intptr_t(fp()) & (wordSize-1)) != 0) { 464 return false; 465 } 466 if (sp() == 0 || (intptr_t(sp()) & (wordSize-1)) != 0) { 467 return false; 468 } 469 if (fp() + interpreter_frame_initial_sp_offset < sp()) { 470 return false; 471 } 472 // These are hacks to keep us out of trouble. 473 // The problem with these is that they mask other problems 474 if (fp() <= sp()) { // this attempts to deal with unsigned comparison above 475 return false; 476 } 477 478 // do some validation of frame elements 479 480 // first the method 481 482 methodOop m = *interpreter_frame_method_addr(); 483 484 // validate the method we'd find in this potential sender 485 if (!Universe::heap()->is_valid_method(m)) return false; 486 487 // stack frames shouldn't be much larger than max_stack elements 488 489 if (fp() - sp() > 1024 + m->max_stack()*Interpreter::stackElementSize()) { 490 return false; 491 } 492 493 // validate bci/bcx 494 495 intptr_t bcx = interpreter_frame_bcx(); 496 if (m->validate_bci_from_bcx(bcx) < 0) { 497 return false; 498 } 499 500 // validate constantPoolCacheOop 501 502 constantPoolCacheOop cp = *interpreter_frame_cache_addr(); 503 504 if (cp == NULL || 505 !Space::is_aligned(cp) || 506 !Universe::heap()->is_permanent((void*)cp)) return false; 507 508 // validate locals 509 510 address locals = (address) *interpreter_frame_locals_addr(); 511 512 if (locals > thread->stack_base() || locals < (address) fp()) return false; 513 514 // We'd have to be pretty unlucky to be mislead at this point 515 516 #endif // CC_INTERP 517 return true; 518 } 519 520 BasicType frame::interpreter_frame_result(oop* oop_result, jvalue* value_result) { 521 #ifdef CC_INTERP 522 // Needed for JVMTI. The result should always be in the interpreterState object 523 assert(false, "NYI"); 524 interpreterState istate = get_interpreterState(); 525 #endif // CC_INTERP 526 assert(is_interpreted_frame(), "interpreted frame expected"); 527 methodOop method = interpreter_frame_method(); 528 BasicType type = method->result_type(); 529 530 intptr_t* tos_addr; 531 if (method->is_native()) { 532 // Prior to calling into the runtime to report the method_exit the possible 533 // return value is pushed to the native stack. If the result is a jfloat/jdouble 534 // then ST0 is saved before EAX/EDX. See the note in generate_native_result 535 tos_addr = (intptr_t*)sp(); 536 if (type == T_FLOAT || type == T_DOUBLE) { 537 // QQQ seems like this code is equivalent on the two platforms 538 #ifdef AMD64 539 // This is times two because we do a push(ltos) after pushing XMM0 540 // and that takes two interpreter stack slots. 541 tos_addr += 2 * Interpreter::stackElementWords(); 542 #else 543 tos_addr += 2; 544 #endif // AMD64 545 } 546 } else { 547 tos_addr = (intptr_t*)interpreter_frame_tos_address(); 548 } 549 550 switch (type) { 551 case T_OBJECT : 552 case T_ARRAY : { 553 oop obj; 554 if (method->is_native()) { 555 #ifdef CC_INTERP 556 obj = istate->_oop_temp; 557 #else 558 obj = (oop) at(interpreter_frame_oop_temp_offset); 559 #endif // CC_INTERP 560 } else { 561 oop* obj_p = (oop*)tos_addr; 562 obj = (obj_p == NULL) ? (oop)NULL : *obj_p; 563 } 564 assert(obj == NULL || Universe::heap()->is_in(obj), "sanity check"); 565 *oop_result = obj; 566 break; 567 } 568 case T_BOOLEAN : value_result->z = *(jboolean*)tos_addr; break; 569 case T_BYTE : value_result->b = *(jbyte*)tos_addr; break; 570 case T_CHAR : value_result->c = *(jchar*)tos_addr; break; 571 case T_SHORT : value_result->s = *(jshort*)tos_addr; break; 572 case T_INT : value_result->i = *(jint*)tos_addr; break; 573 case T_LONG : value_result->j = *(jlong*)tos_addr; break; 574 case T_FLOAT : { 575 #ifdef AMD64 576 value_result->f = *(jfloat*)tos_addr; 577 #else 578 if (method->is_native()) { 579 jdouble d = *(jdouble*)tos_addr; // Result was in ST0 so need to convert to jfloat 580 value_result->f = (jfloat)d; 581 } else { 582 value_result->f = *(jfloat*)tos_addr; 583 } 584 #endif // AMD64 585 break; 586 } 587 case T_DOUBLE : value_result->d = *(jdouble*)tos_addr; break; 588 case T_VOID : /* Nothing to do */ break; 589 default : ShouldNotReachHere(); 590 } 591 592 return type; 593 } 594 595 596 intptr_t* frame::interpreter_frame_tos_at(jint offset) const { 597 int index = (Interpreter::expr_offset_in_bytes(offset)/wordSize); 598 return &interpreter_frame_tos_address()[index]; 599 }