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  */

    24 

    25 #include "incls/_precompiled.incl"

    26 #include "incls/_javaCalls.cpp.incl"

    27 

    28 // -----------------------------------------------------

    29 // Implementation of JavaCallWrapper

    30 

    31 JavaCallWrapper::JavaCallWrapper(methodHandle callee_method, Handle receiver, JavaValue* result, TRAPS) {

    32   JavaThread* thread = (JavaThread *)THREAD;

    33   bool clear_pending_exception = true;

    34 

    35   guarantee(thread->is_Java_thread(), "crucial check - the VM thread cannot and must not escape to Java code");

    36   assert(!thread->owns_locks(), "must release all locks when leaving VM");

    37   guarantee(!thread->is_Compiler_thread(), "cannot make java calls from the compiler");

    38   _result   = result;

    39 

    40   // Make sure that that the value of the  higest_lock is at least the same as the current stackpointer,

    41   // since, the Java code is highly likely to use locks.

    42   // Use '(address)this' to guarantee that highest_lock address is conservative and inside our thread

    43   thread->update_highest_lock((address)this);

    44 

    45   // Allocate handle block for Java code. This must be done before we change thread_state to _thread_in_Java_or_stub,

    46   // since it can potentially block.

    47   JNIHandleBlock* new_handles = JNIHandleBlock::allocate_block(thread);

    48 

    49   // After this, we are official in JavaCode. This needs to be done before we change any of the thread local

    50   // info, since we cannot find oops before the new information is set up completely.

    51   ThreadStateTransition::transition(thread, _thread_in_vm, _thread_in_Java);

    52 

    53   // Make sure that we handle asynchronous stops and suspends _before_ we clear all thread state

    54   // in JavaCallWrapper::JavaCallWrapper(). This way, we can decide if we need to do any pd actions

    55   // to prepare for stop/suspend (flush register windows on sparcs, cache sp, or other state).

    56   if (thread->has_special_runtime_exit_condition()) {

    57     thread->handle_special_runtime_exit_condition();

    58     if (HAS_PENDING_EXCEPTION) {

    59       clear_pending_exception = false;

    60     }

    61   }

    62 

    63 

    64   // Make sure to set the oop's after the thread transition - since we can block there. No one is GC'ing

    65   // the JavaCallWrapper before the entry frame is on the stack.

    66   _callee_method = callee_method();

    67   _receiver = receiver();

    68 

    69 #ifdef CHECK_UNHANDLED_OOPS

    70   THREAD->allow_unhandled_oop(&_callee_method);

    71   THREAD->allow_unhandled_oop(&_receiver);

    72 #endif // CHECK_UNHANDLED_OOPS

    73 

    74   _thread       = (JavaThread *)thread;

    75   _handles      = _thread->active_handles();    // save previous handle block & Java frame linkage

    76 

    77   // For the profiler, the last_Java_frame information in thread must always be in

    78   // legal state. We have no last Java frame if last_Java_sp == NULL so

    79   // the valid transition is to clear _last_Java_sp and then reset the rest of

    80   // the (platform specific) state.

    81 

    82   _anchor.copy(_thread->frame_anchor());

    83   _thread->frame_anchor()->clear();

    84 

    85   debug_only(_thread->inc_java_call_counter());

    86   _thread->set_active_handles(new_handles);     // install new handle block and reset Java frame linkage

    87 

    88   assert (_thread->thread_state() != _thread_in_native, "cannot set native pc to NULL");

    89 

    90   // clear any pending exception in thread (native calls start with no exception pending)

    91   if(clear_pending_exception) {

    92     _thread->clear_pending_exception();

    93   }

    94 

    95   if (_anchor.last_Java_sp() == NULL) {

    96     _thread->record_base_of_stack_pointer();

    97   }

    98 }

    99 

   100 

   101 JavaCallWrapper::~JavaCallWrapper() {

   102   assert(_thread == JavaThread::current(), "must still be the same thread");

   103 

   104   // restore previous handle block & Java frame linkage

   105   JNIHandleBlock *_old_handles = _thread->active_handles();

   106   _thread->set_active_handles(_handles);

   107 

   108   _thread->frame_anchor()->zap();

   109 

   110   debug_only(_thread->dec_java_call_counter());

   111 

   112   if (_anchor.last_Java_sp() == NULL) {

   113     _thread->set_base_of_stack_pointer(NULL);

   114   }

   115 

   116 

   117   // Old thread-local info. has been restored. We are not back in the VM.

   118   ThreadStateTransition::transition_from_java(_thread, _thread_in_vm);

   119 

   120   // State has been restored now make the anchor frame visible for the profiler.

   121   // Do this after the transition because this allows us to put an assert

   122   // the Java->vm transition which checks to see that stack is not walkable

   123   // on sparc/ia64 which will catch violations of the reseting of last_Java_frame

   124   // invariants (i.e. _flags always cleared on return to Java)

   125 

   126   _thread->frame_anchor()->copy(&_anchor);

   127 

   128   // Release handles after we are marked as being inside the VM again, since this

   129   // operation might block

   130   JNIHandleBlock::release_block(_old_handles, _thread);

   131 }

   132 

   133 

   134 void JavaCallWrapper::oops_do(OopClosure* f) {

   135   f->do_oop((oop*)&_callee_method);

   136   f->do_oop((oop*)&_receiver);

   137   handles()->oops_do(f);

   138 }

   139 

   140 

   141 // Helper methods

   142 static BasicType runtime_type_from(JavaValue* result) {

   143   switch (result->get_type()) {

   144     case T_BOOLEAN: // fall through

   145     case T_CHAR   : // fall through

   146     case T_SHORT  : // fall through

   147     case T_INT    : // fall through

   148 #ifndef _LP64

   149     case T_OBJECT : // fall through

   150     case T_ARRAY  : // fall through

   151 #endif

   152     case T_BYTE   : // fall through

   153     case T_VOID   : return T_INT;

   154     case T_LONG   : return T_LONG;

   155     case T_FLOAT  : return T_FLOAT;

   156     case T_DOUBLE : return T_DOUBLE;

   157 #ifdef _LP64

   158     case T_ARRAY  : // fall through

   159     case T_OBJECT:  return T_OBJECT;

   160 #endif

   161   }

   162   ShouldNotReachHere();

   163   return T_ILLEGAL;

   164 }

   165 

   166 // ===== object constructor calls =====

   167 

   168 void JavaCalls::call_default_constructor(JavaThread* thread, methodHandle method, Handle receiver, TRAPS) {

   169   assert(method->name() == vmSymbols::object_initializer_name(),    "Should only be called for default constructor");

   170   assert(method->signature() == vmSymbols::void_method_signature(), "Should only be called for default constructor");

   171 

   172   instanceKlass* ik = instanceKlass::cast(method->method_holder());

   173   if (ik->is_initialized() && ik->has_vanilla_constructor()) {

   174     // safe to skip constructor call

   175   } else {

   176     static JavaValue result(T_VOID);

   177     JavaCallArguments args(receiver);

   178     call(&result, method, &args, CHECK);

   179   }

   180 }

   181 

   182 // ============ Virtual calls ============

   183 

   184 void JavaCalls::call_virtual(JavaValue* result, KlassHandle spec_klass, symbolHandle name, symbolHandle signature, JavaCallArguments* args, TRAPS) {

   185   CallInfo callinfo;

   186   Handle receiver = args->receiver();

   187   KlassHandle recvrKlass(THREAD, receiver.is_null() ? (klassOop)NULL : receiver->klass());

   188   LinkResolver::resolve_virtual_call(

   189           callinfo, receiver, recvrKlass, spec_klass, name, signature,

   190           KlassHandle(), false, true, CHECK);

   191   methodHandle method = callinfo.selected_method();

   192   assert(method.not_null(), "should have thrown exception");

   193 

   194   // Invoke the method

   195   JavaCalls::call(result, method, args, CHECK);

   196 }

   197 

   198 

   199 void JavaCalls::call_virtual(JavaValue* result, Handle receiver, KlassHandle spec_klass, symbolHandle name, symbolHandle signature, TRAPS) {

   200   JavaCallArguments args(receiver); // One oop argument

   201   call_virtual(result, spec_klass, name, signature, &args, CHECK);

   202 }

   203 

   204 

   205 void JavaCalls::call_virtual(JavaValue* result, Handle receiver, KlassHandle spec_klass, symbolHandle name, symbolHandle signature, Handle arg1, TRAPS) {

   206   JavaCallArguments args(receiver); // One oop argument

   207   args.push_oop(arg1);

   208   call_virtual(result, spec_klass, name, signature, &args, CHECK);

   209 }

   210 

   211 

   212 

   213 void JavaCalls::call_virtual(JavaValue* result, Handle receiver, KlassHandle spec_klass, symbolHandle name, symbolHandle signature, Handle arg1, Handle arg2, TRAPS) {

   214   JavaCallArguments args(receiver); // One oop argument

   215   args.push_oop(arg1);

   216   args.push_oop(arg2);

   217   call_virtual(result, spec_klass, name, signature, &args, CHECK);

   218 }

   219 

   220 

   221 // ============ Special calls ============

   222 

   223 void JavaCalls::call_special(JavaValue* result, KlassHandle klass, symbolHandle name, symbolHandle signature, JavaCallArguments* args, TRAPS) {

   224   CallInfo callinfo;

   225   LinkResolver::resolve_special_call(callinfo, klass, name, signature, KlassHandle(), false, CHECK);

   226   methodHandle method = callinfo.selected_method();

   227   assert(method.not_null(), "should have thrown exception");

   228 

   229   // Invoke the method

   230   JavaCalls::call(result, method, args, CHECK);

   231 }

   232 

   233 

   234 void JavaCalls::call_special(JavaValue* result, Handle receiver, KlassHandle klass, symbolHandle name, symbolHandle signature, TRAPS) {

   235   JavaCallArguments args(receiver); // One oop argument

   236   call_special(result, klass, name, signature, &args, CHECK);

   237 }

   238 

   239 

   240 void JavaCalls::call_special(JavaValue* result, Handle receiver, KlassHandle klass, symbolHandle name, symbolHandle signature, Handle arg1, TRAPS) {

   241   JavaCallArguments args(receiver); // One oop argument

   242   args.push_oop(arg1);

   243   call_special(result, klass, name, signature, &args, CHECK);

   244 }

   245 

   246 

   247 void JavaCalls::call_special(JavaValue* result, Handle receiver, KlassHandle klass, symbolHandle name, symbolHandle signature, Handle arg1, Handle arg2, TRAPS) {

   248   JavaCallArguments args(receiver); // One oop argument

   249   args.push_oop(arg1);

   250   args.push_oop(arg2);

   251   call_special(result, klass, name, signature, &args, CHECK);

   252 }

   253 

   254 

   255 // ============ Static calls ============

   256 

   257 void JavaCalls::call_static(JavaValue* result, KlassHandle klass, symbolHandle name, symbolHandle signature, JavaCallArguments* args, TRAPS) {

   258   CallInfo callinfo;

   259   LinkResolver::resolve_static_call(callinfo, klass, name, signature, KlassHandle(), false, true, CHECK);

   260   methodHandle method = callinfo.selected_method();

   261   assert(method.not_null(), "should have thrown exception");

   262 

   263   // Invoke the method

   264   JavaCalls::call(result, method, args, CHECK);

   265 }

   266 

   267 

   268 void JavaCalls::call_static(JavaValue* result, KlassHandle klass, symbolHandle name, symbolHandle signature, TRAPS) {

   269   JavaCallArguments args; // No argument

   270   call_static(result, klass, name, signature, &args, CHECK);

   271 }

   272 

   273 

   274 void JavaCalls::call_static(JavaValue* result, KlassHandle klass, symbolHandle name, symbolHandle signature, Handle arg1, TRAPS) {

   275   JavaCallArguments args(arg1); // One oop argument

   276   call_static(result, klass, name, signature, &args, CHECK);

   277 }

   278 

   279 

   280 void JavaCalls::call_static(JavaValue* result, KlassHandle klass, symbolHandle name, symbolHandle signature, Handle arg1, Handle arg2, TRAPS) {

   281   JavaCallArguments args; // One oop argument

   282   args.push_oop(arg1);

   283   args.push_oop(arg2);

   284   call_static(result, klass, name, signature, &args, CHECK);

   285 }

   286 

   287 

   288 // -------------------------------------------------

   289 // Implementation of JavaCalls (low level)

   290 

   291 

   292 void JavaCalls::call(JavaValue* result, methodHandle method, JavaCallArguments* args, TRAPS) {

   293   // Check if we need to wrap a potential OS exception handler around thread

   294   // This is used for e.g. Win32 structured exception handlers

   295   assert(THREAD->is_Java_thread(), "only JavaThreads can make JavaCalls");

   296   // Need to wrap each and everytime, since there might be native code down the

   297   // stack that has installed its own exception handlers

   298   os::os_exception_wrapper(call_helper, result, &method, args, THREAD);

   299 }

   300 

   301 void JavaCalls::call_helper(JavaValue* result, methodHandle* m, JavaCallArguments* args, TRAPS) {

   302   methodHandle method = *m;

   303   JavaThread* thread = (JavaThread*)THREAD;

   304   assert(thread->is_Java_thread(), "must be called by a java thread");

   305   assert(method.not_null(), "must have a method to call");

   306   assert(!SafepointSynchronize::is_at_safepoint(), "call to Java code during VM operation");

   307   assert(!thread->handle_area()->no_handle_mark_active(), "cannot call out to Java here");

   308 

   309 

   310   CHECK_UNHANDLED_OOPS_ONLY(thread->clear_unhandled_oops();)

   311 

   312   // Make sure that the arguments have the right type

   313   debug_only(args->verify(method, result->get_type(), thread));

   314 

   315   // Ignore call if method is empty

   316   if (method->is_empty_method()) {

   317     assert(result->get_type() == T_VOID, "an empty method must return a void value");

   318     return;

   319   }

   320 

   321 

   322 #ifdef ASSERT

   323   { klassOop holder = method->method_holder();

   324     // A klass might not be initialized since JavaCall's might be used during the executing of

   325     // the <clinit>. For example, a Thread.start might start executing on an object that is

   326     // not fully initialized! (bad Java programming style)

   327     assert(instanceKlass::cast(holder)->is_linked(), "rewritting must have taken place");

   328   }

   329 #endif

   330 

   331 

   332   assert(!thread->is_Compiler_thread(), "cannot compile from the compiler");

   333   if (CompilationPolicy::mustBeCompiled(method)) {

   334     CompileBroker::compile_method(method, InvocationEntryBci,

   335                                   methodHandle(), 0, "mustBeCompiled", CHECK);

   336   }

   337 

   338   // Since the call stub sets up like the interpreter we call the from_interpreted_entry

   339   // so we can go compiled via a i2c. Otherwise initial entry method will always

   340   // run interpreted.

   341   address entry_point = method->from_interpreted_entry();

   342   if (JvmtiExport::can_post_interpreter_events() && thread->is_interp_only_mode()) {

   343     entry_point = method->interpreter_entry();

   344   }

   345 

   346   // Figure out if the result value is an oop or not (Note: This is a different value

   347   // than result_type. result_type will be T_INT of oops. (it is about size)

   348   BasicType result_type = runtime_type_from(result);

   349   bool oop_result_flag = (result->get_type() == T_OBJECT || result->get_type() == T_ARRAY);

   350 

   351   // NOTE: if we move the computation of the result_val_address inside

   352   // the call to call_stub, the optimizer produces wrong code.

   353   intptr_t* result_val_address = (intptr_t*)(result->get_value_addr());

   354 

   355   // Find receiver

   356   Handle receiver = (!method->is_static()) ? args->receiver() : Handle();

   357 

   358   // When we reenter Java, we need to reenable the yellow zone which

   359   // might already be disabled when we are in VM.

   360   if (thread->stack_yellow_zone_disabled()) {

   361     thread->reguard_stack();

   362   }

   363 

   364   // Check that there are shadow pages available before changing thread state

   365   // to Java

   366   if (!os::stack_shadow_pages_available(THREAD, method)) {

   367     // Throw stack overflow exception with preinitialized exception.

   368     Exceptions::throw_stack_overflow_exception(THREAD, __FILE__, __LINE__);

   369     return;

   370   } else {

   371     // Touch pages checked if the OS needs them to be touched to be mapped.

   372     os::bang_stack_shadow_pages();

   373   }

   374 

   375   // do call

   376   { JavaCallWrapper link(method, receiver, result, CHECK);

   377     { HandleMark hm(thread);  // HandleMark used by HandleMarkCleaner

   378 

   379       StubRoutines::call_stub()(

   380         (address)&link,

   381         // (intptr_t*)&(result->_value), // see NOTE above (compiler problem)

   382         result_val_address,          // see NOTE above (compiler problem)

   383         result_type,

   384         method(),

   385         entry_point,

   386         args->parameters(),

   387         args->size_of_parameters(),

   388         CHECK

   389       );

   390 

   391       result = link.result();  // circumvent MS C++ 5.0 compiler bug (result is clobbered across call)

   392       // Preserve oop return value across possible gc points

   393       if (oop_result_flag) {

   394         thread->set_vm_result((oop) result->get_jobject());

   395       }

   396     }

   397   } // Exit JavaCallWrapper (can block - potential return oop must be preserved)

   398 

   399   // Check if a thread stop or suspend should be executed

   400   // The following assert was not realistic.  Thread.stop can set that bit at any moment.

   401   //assert(!thread->has_special_runtime_exit_condition(), "no async. exceptions should be installed");

   402 

   403   // Restore possible oop return

   404   if (oop_result_flag) {

   405     result->set_jobject((jobject)thread->vm_result());

   406     thread->set_vm_result(NULL);

   407   }

   408 }

   409 

   410 

   411 //--------------------------------------------------------------------------------------

   412 // Implementation of JavaCallArguments

   413 

   414 intptr_t* JavaCallArguments::parameters() {

   415   // First convert all handles to oops

   416   for(int i = 0; i < _size; i++) {

   417     if (_is_oop[i]) {

   418       // Handle conversion

   419       _value[i] = (intptr_t)Handle::raw_resolve((oop *)_value[i]);

   420     }

   421     // The parameters are moved to the parameters array to include the tags.

   422     if (TaggedStackInterpreter) {

   423       // Tags are interspersed with arguments.  Tags are first.

   424       int tagged_index = i*2;

   425       _parameters[tagged_index]   = _is_oop[i] ? frame::TagReference :

   426                                                  frame::TagValue;

   427       _parameters[tagged_index+1] = _value[i];

   428     }

   429   }

   430   // Return argument vector

   431   return TaggedStackInterpreter ? _parameters : _value;

   432 }

   433 

   434 //--------------------------------------------------------------------------------------

   435 // Non-Product code

   436 #ifndef PRODUCT

   437 

   438 class SignatureChekker : public SignatureIterator {

   439  private:

   440    bool *_is_oop;

   441    int   _pos;

   442    BasicType _return_type;

   443 

   444  public:

   445   bool _is_return;

   446 

   447   SignatureChekker(symbolHandle signature, BasicType return_type, bool is_static, bool* is_oop) : SignatureIterator(signature) {

   448     _is_oop = is_oop;

   449     _is_return = false;

   450     _return_type = return_type;

   451     _pos = 0;

   452     if (!is_static) {

   453       check_value(true); // Receiver must be an oop

   454     }

   455   }

   456 

   457   void check_value(bool type) {

   458     guarantee(_is_oop[_pos++] == type, "signature does not match pushed arguments");

   459   }

   460 

   461   void check_doing_return(bool state) { _is_return = state; }

   462 

   463   void check_return_type(BasicType t) {

   464     guarantee(_is_return && t == _return_type, "return type does not match");

   465   }

   466 

   467   void check_int(BasicType t) {

   468     if (_is_return) {

   469       check_return_type(t);

   470       return;

   471     }

   472     check_value(false);

   473   }

   474 

   475   void check_double(BasicType t) { check_long(t); }

   476 

   477   void check_long(BasicType t) {

   478     if (_is_return) {

   479       check_return_type(t);

   480       return;

   481     }

   482 

   483     check_value(false);

   484     check_value(false);

   485   }

   486 

   487   void check_obj(BasicType t) {

   488     if (_is_return) {

   489       check_return_type(t);

   490       return;

   491     }

   492     check_value(true);

   493   }

   494 

   495   void do_bool()                       { check_int(T_BOOLEAN);       }

   496   void do_char()                       { check_int(T_CHAR);          }

   497   void do_float()                      { check_int(T_FLOAT);         }

   498   void do_double()                     { check_double(T_DOUBLE);     }

   499   void do_byte()                       { check_int(T_BYTE);          }

   500   void do_short()                      { check_int(T_SHORT);         }

   501   void do_int()                        { check_int(T_INT);           }

   502   void do_long()                       { check_long(T_LONG);         }

   503   void do_void()                       { check_return_type(T_VOID);  }

   504   void do_object(int begin, int end)   { check_obj(T_OBJECT);        }

   505   void do_array(int begin, int end)    { check_obj(T_OBJECT);        }

   506 };

   507 

   508 void JavaCallArguments::verify(methodHandle method, BasicType return_type,

   509   Thread *thread) {

   510   guarantee(method->size_of_parameters() == size_of_parameters(), "wrong no. of arguments pushed");

   511 

   512   // Treat T_OBJECT and T_ARRAY as the same

   513   if (return_type == T_ARRAY) return_type = T_OBJECT;

   514 

   515   // Check that oop information is correct

   516   symbolHandle signature (thread,  method->signature());

   517 

   518   SignatureChekker sc(signature, return_type, method->is_static(),_is_oop);

   519   sc.iterate_parameters();

   520   sc.check_doing_return(true);

   521   sc.iterate_returntype();

   522 }

   523 

   524 #endif // PRODUCT