src/cpu/x86/vm/frame_x86.cpp

Wed, 21 May 2008 10:45:07 -0700

author
kvn
date
Wed, 21 May 2008 10:45:07 -0700
changeset 598
885ed790ecf0
parent 542
93b6525e3b82
child 631
d1605aabd0a1
permissions
-rw-r--r--

6695810: null oop passed to encode_heap_oop_not_null
Summary: fix several problems in C2 related to Escape Analysis and Compressed Oops.
Reviewed-by: never, jrose

     1 /*
     2  * Copyright 1997-2007 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  */
    25 # include "incls/_precompiled.incl"
    26 # include "incls/_frame_x86.cpp.incl"
    28 #ifdef ASSERT
    29 void RegisterMap::check_location_valid() {
    30 }
    31 #endif
    34 // Profiling/safepoint support
    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());
    44   if (!sp_safe) {
    45     return false;
    46   }
    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);
    52   if (!unextended_sp_safe) {
    53     return false;
    54   }
    56   // an fp must be within the stack and above (but not equal) sp
    57   bool fp_safe = (fp <= thread->stack_base()) && (fp > sp);
    59   // We know sp/unextended_sp are safe only fp is questionable here
    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
    65   if (_cb != NULL ) {
    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.
    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.
    81       if (!fp_safe) return false;
    83       // Validate the JavaCallWrapper an entry frame must have
    85       address jcw = (address)entry_frame_call_wrapper();
    87       bool jcw_safe = (jcw <= thread->stack_base()) && ( jcw > fp);
    89       return jcw_safe;
    91     }
    93     intptr_t* sender_sp = NULL;
    94     address   sender_pc = NULL;
    96     if (is_interpreted_frame()) {
    97       // fp must be safe
    98       if (!fp_safe) {
    99         return false;
   100       }
   102       sender_pc = (address) this->fp()[return_addr_offset];
   103       sender_sp = (intptr_t*) addr_at(sender_sp_offset);
   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?)
   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     }
   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     }
   121     // If the potential sender is the interpreter then we can do some more checking
   122     if (Interpreter::contains(sender_pc)) {
   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.
   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);
   131       if (!saved_fp_safe) {
   132         return false;
   133       }
   135       // construct the potential sender
   137       frame sender(sender_sp, saved_fp, sender_pc);
   139       return sender.is_interpreted_frame_valid(thread);
   141     }
   143     // Could just be some random pointer within the codeBlob
   145     if (!sender_blob->instructions_contains(sender_pc)) return false;
   147     // We should never be able to see an adapter if the current frame is something from code cache
   149     if ( sender_blob->is_adapter_blob()) {
   150       return false;
   151     }
   153     // Could be the call_stub
   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);
   159       if (!saved_fp_safe) {
   160         return false;
   161       }
   163       // construct the potential sender
   165       frame sender(sender_sp, saved_fp, sender_pc);
   167       // Validate the JavaCallWrapper an entry frame must have
   168       address jcw = (address)sender.entry_frame_call_wrapper();
   170       bool jcw_safe = (jcw <= thread->stack_base()) && ( jcw > (address)sender.fp());
   172       return jcw_safe;
   173     }
   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.
   178     if (sender_blob->frame_size() == 0) {
   179       assert(!sender_blob->is_nmethod(), "should count return address at least");
   180       return false;
   181     }
   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.
   188     assert(sender_blob->is_nmethod(), "Impossible call chain");
   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...
   193     // One idea is seeing if the sender_pc we have is one that we'd expect to call to current cb
   195     // We've validated the potential sender that would be created
   196     return true;
   197   }
   199   // Must be native-compiled frame. Since sender will try and use fp to find
   200   // linkages it must be safe
   202   if (!fp_safe) {
   203     return false;
   204   }
   206   // Will the pc we fetch be non-zero (which we'll find at the oldest frame)
   208   if ( (address) this->fp()[return_addr_offset] == NULL) return false;
   211   // could try and do some more potential verification of native frame if we could think of some...
   213   return true;
   215 }
   218 void frame::patch_pc(Thread* thread, address pc) {
   219   if (TracePcPatching) {
   220     tty->print_cr("patch_pc at address  0x%x [0x%x -> 0x%x] ", &((address *)sp())[-1], ((address *)sp())[-1], pc);
   221   }
   222   ((address *)sp())[-1] = pc;
   223   _cb = CodeCache::find_blob(pc);
   224   if (_cb != NULL && _cb->is_nmethod() && ((nmethod*)_cb)->is_deopt_pc(_pc)) {
   225     address orig = (((nmethod*)_cb)->get_original_pc(this));
   226     assert(orig == _pc, "expected original to be stored before patching");
   227     _deopt_state = is_deoptimized;
   228     // leave _pc as is
   229   } else {
   230     _deopt_state = not_deoptimized;
   231     _pc = pc;
   232   }
   233 }
   235 bool frame::is_interpreted_frame() const  {
   236   return Interpreter::contains(pc());
   237 }
   239 int frame::frame_size() const {
   240   RegisterMap map(JavaThread::current(), false);
   241   frame sender = this->sender(&map);
   242   return sender.sp() - sp();
   243 }
   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 }
   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 }
   262 // monitor elements
   264 BasicObjectLock* frame::interpreter_frame_monitor_begin() const {
   265   return get_interpreterState()->monitor_base();
   266 }
   268 BasicObjectLock* frame::interpreter_frame_monitor_end() const {
   269   return (BasicObjectLock*) get_interpreterState()->stack_base();
   270 }
   272 #else // CC_INTERP
   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 }
   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 }
   285 // monitor elements
   287 BasicObjectLock* frame::interpreter_frame_monitor_begin() const {
   288   return (BasicObjectLock*) addr_at(interpreter_frame_monitor_block_bottom_offset);
   289 }
   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 }
   299 void frame::interpreter_frame_set_monitor_end(BasicObjectLock* value) {
   300   *((BasicObjectLock**)addr_at(interpreter_frame_monitor_block_top_offset)) = value;
   301 }
   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
   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 }
   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);
   330   // This is the sp before any possible extension (adapter/locals).
   331   intptr_t* unextended_sp = interpreter_frame_sender_sp();
   333   // The interpreter and compiler(s) always save EBP/RBP in a known
   334   // location on entry. We must record where that location is
   335   // so this if EBP/RBP was live on callout from c2 we can find
   336   // the saved copy no matter what it called.
   338   // Since the interpreter always saves EBP/RBP if we record where it is then
   339   // we don't have to always save EBP/RBP on entry and exit to c2 compiled
   340   // code, on entry will be enough.
   341 #ifdef COMPILER2
   342   if (map->update_map()) {
   343     map->set_location(rbp->as_VMReg(), (address) addr_at(link_offset));
   344 #ifdef AMD64
   345     // this is weird "H" ought to be at a higher address however the
   346     // oopMaps seems to have the "H" regs at the same address and the
   347     // vanilla register.
   348     // XXXX make this go away
   349     if (true) {
   350       map->set_location(rbp->as_VMReg()->next(), (address)addr_at(link_offset));
   351     }
   352 #endif // AMD64
   353   }
   354 #endif /* COMPILER2 */
   355   return frame(sp, unextended_sp, link(), sender_pc());
   356 }
   359 //------------------------------sender_for_compiled_frame-----------------------
   360 frame frame::sender_for_compiled_frame(RegisterMap* map) const {
   361   assert(map != NULL, "map must be set");
   362   const bool c1_compiled = _cb->is_compiled_by_c1();
   364   // frame owned by optimizing compiler
   365   intptr_t* sender_sp = NULL;
   367   assert(_cb->frame_size() >= 0, "must have non-zero frame size");
   368   sender_sp = unextended_sp() + _cb->frame_size();
   370   // On Intel the return_address is always the word on the stack
   371   address sender_pc = (address) *(sender_sp-1);
   373   // This is the saved value of ebp which may or may not really be an fp.
   374   // it is only an fp if the sender is an interpreter frame (or c1?)
   376   intptr_t *saved_fp = (intptr_t*)*(sender_sp - frame::sender_sp_offset);
   378   if (map->update_map()) {
   379     // Tell GC to use argument oopmaps for some runtime stubs that need it.
   380     // For C1, the runtime stub might not have oop maps, so set this flag
   381     // outside of update_register_map.
   382     map->set_include_argument_oops(_cb->caller_must_gc_arguments(map->thread()));
   383     if (_cb->oop_maps() != NULL) {
   384       OopMapSet::update_register_map(this, map);
   385     }
   386     // Since the prolog does the save and restore of epb there is no oopmap
   387     // for it so we must fill in its location as if there was an oopmap entry
   388     // since if our caller was compiled code there could be live jvm state in it.
   389     map->set_location(rbp->as_VMReg(), (address) (sender_sp - frame::sender_sp_offset));
   390 #ifdef AMD64
   391     // this is weird "H" ought to be at a higher address however the
   392     // oopMaps seems to have the "H" regs at the same address and the
   393     // vanilla register.
   394     // XXXX make this go away
   395     if (true) {
   396       map->set_location(rbp->as_VMReg()->next(), (address) (sender_sp - frame::sender_sp_offset));
   397     }
   398 #endif // AMD64
   399   }
   401   assert(sender_sp != sp(), "must have changed");
   402   return frame(sender_sp, saved_fp, sender_pc);
   403 }
   405 frame frame::sender(RegisterMap* map) const {
   406   // Default is we done have to follow them. The sender_for_xxx will
   407   // update it accordingly
   408   map->set_include_argument_oops(false);
   410   if (is_entry_frame())       return sender_for_entry_frame(map);
   411   if (is_interpreted_frame()) return sender_for_interpreter_frame(map);
   412   assert(_cb == CodeCache::find_blob(pc()),"Must be the same");
   414   if (_cb != NULL) {
   415     return sender_for_compiled_frame(map);
   416   }
   417   // Must be native-compiled frame, i.e. the marshaling code for native
   418   // methods that exists in the core system.
   419   return frame(sender_sp(), link(), sender_pc());
   420 }
   423 bool frame::interpreter_frame_equals_unpacked_fp(intptr_t* fp) {
   424   assert(is_interpreted_frame(), "must be interpreter frame");
   425   methodOop method = interpreter_frame_method();
   426   // When unpacking an optimized frame the frame pointer is
   427   // adjusted with:
   428   int diff = (method->max_locals() - method->size_of_parameters()) *
   429              Interpreter::stackElementWords();
   430   return _fp == (fp - diff);
   431 }
   433 void frame::pd_gc_epilog() {
   434   // nothing done here now
   435 }
   437 bool frame::is_interpreted_frame_valid(JavaThread* thread) const {
   438 // QQQ
   439 #ifdef CC_INTERP
   440 #else
   441   assert(is_interpreted_frame(), "Not an interpreted frame");
   442   // These are reasonable sanity checks
   443   if (fp() == 0 || (intptr_t(fp()) & (wordSize-1)) != 0) {
   444     return false;
   445   }
   446   if (sp() == 0 || (intptr_t(sp()) & (wordSize-1)) != 0) {
   447     return false;
   448   }
   449   if (fp() + interpreter_frame_initial_sp_offset < sp()) {
   450     return false;
   451   }
   452   // These are hacks to keep us out of trouble.
   453   // The problem with these is that they mask other problems
   454   if (fp() <= sp()) {        // this attempts to deal with unsigned comparison above
   455     return false;
   456   }
   458   // do some validation of frame elements
   460   // first the method
   462   methodOop m = *interpreter_frame_method_addr();
   464   // validate the method we'd find in this potential sender
   465   if (!Universe::heap()->is_valid_method(m)) return false;
   467   // stack frames shouldn't be much larger than max_stack elements
   469   if (fp() - sp() > 1024 + m->max_stack()*Interpreter::stackElementSize()) {
   470     return false;
   471   }
   473   // validate bci/bcx
   475   intptr_t  bcx    = interpreter_frame_bcx();
   476   if (m->validate_bci_from_bcx(bcx) < 0) {
   477     return false;
   478   }
   480   // validate constantPoolCacheOop
   482   constantPoolCacheOop cp = *interpreter_frame_cache_addr();
   484   if (cp == NULL ||
   485       !Space::is_aligned(cp) ||
   486       !Universe::heap()->is_permanent((void*)cp)) return false;
   488   // validate locals
   490   address locals =  (address) *interpreter_frame_locals_addr();
   492   if (locals > thread->stack_base() || locals < (address) fp()) return false;
   494   // We'd have to be pretty unlucky to be mislead at this point
   496 #endif // CC_INTERP
   497   return true;
   498 }
   500 BasicType frame::interpreter_frame_result(oop* oop_result, jvalue* value_result) {
   501 #ifdef CC_INTERP
   502   // Needed for JVMTI. The result should always be in the interpreterState object
   503   assert(false, "NYI");
   504   interpreterState istate = get_interpreterState();
   505 #endif // CC_INTERP
   506   assert(is_interpreted_frame(), "interpreted frame expected");
   507   methodOop method = interpreter_frame_method();
   508   BasicType type = method->result_type();
   510   intptr_t* tos_addr;
   511   if (method->is_native()) {
   512     // Prior to calling into the runtime to report the method_exit the possible
   513     // return value is pushed to the native stack. If the result is a jfloat/jdouble
   514     // then ST0 is saved before EAX/EDX. See the note in generate_native_result
   515     tos_addr = (intptr_t*)sp();
   516     if (type == T_FLOAT || type == T_DOUBLE) {
   517     // QQQ seems like this code is equivalent on the two platforms
   518 #ifdef AMD64
   519       // This is times two because we do a push(ltos) after pushing XMM0
   520       // and that takes two interpreter stack slots.
   521       tos_addr += 2 * Interpreter::stackElementWords();
   522 #else
   523       tos_addr += 2;
   524 #endif // AMD64
   525     }
   526   } else {
   527     tos_addr = (intptr_t*)interpreter_frame_tos_address();
   528   }
   530   switch (type) {
   531     case T_OBJECT  :
   532     case T_ARRAY   : {
   533       oop obj;
   534       if (method->is_native()) {
   535 #ifdef CC_INTERP
   536         obj = istate->_oop_temp;
   537 #else
   538         obj = (oop) at(interpreter_frame_oop_temp_offset);
   539 #endif // CC_INTERP
   540       } else {
   541         oop* obj_p = (oop*)tos_addr;
   542         obj = (obj_p == NULL) ? (oop)NULL : *obj_p;
   543       }
   544       assert(obj == NULL || Universe::heap()->is_in(obj), "sanity check");
   545       *oop_result = obj;
   546       break;
   547     }
   548     case T_BOOLEAN : value_result->z = *(jboolean*)tos_addr; break;
   549     case T_BYTE    : value_result->b = *(jbyte*)tos_addr; break;
   550     case T_CHAR    : value_result->c = *(jchar*)tos_addr; break;
   551     case T_SHORT   : value_result->s = *(jshort*)tos_addr; break;
   552     case T_INT     : value_result->i = *(jint*)tos_addr; break;
   553     case T_LONG    : value_result->j = *(jlong*)tos_addr; break;
   554     case T_FLOAT   : {
   555 #ifdef AMD64
   556         value_result->f = *(jfloat*)tos_addr;
   557 #else
   558       if (method->is_native()) {
   559         jdouble d = *(jdouble*)tos_addr;  // Result was in ST0 so need to convert to jfloat
   560         value_result->f = (jfloat)d;
   561       } else {
   562         value_result->f = *(jfloat*)tos_addr;
   563       }
   564 #endif // AMD64
   565       break;
   566     }
   567     case T_DOUBLE  : value_result->d = *(jdouble*)tos_addr; break;
   568     case T_VOID    : /* Nothing to do */ break;
   569     default        : ShouldNotReachHere();
   570   }
   572   return type;
   573 }
   576 intptr_t* frame::interpreter_frame_tos_at(jint offset) const {
   577   int index = (Interpreter::expr_offset_in_bytes(offset)/wordSize);
   578   return &interpreter_frame_tos_address()[index];
   579 }

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