1 /*
   2  * Copyright (c) 1997, 2015, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "precompiled.hpp"
  26 #include "classfile/systemDictionary.hpp"
  27 #include "classfile/vmSymbols.hpp"
  28 #include "code/nmethod.hpp"
  29 #include "compiler/compileBroker.hpp"
  30 #include "interpreter/interpreter.hpp"
  31 #include "interpreter/linkResolver.hpp"
  32 #include "memory/universe.inline.hpp"
  33 #include "oops/oop.inline.hpp"
  34 #include "prims/jniCheck.hpp"
  35 #include "runtime/compilationPolicy.hpp"
  36 #include "runtime/handles.inline.hpp"
  37 #include "runtime/interfaceSupport.hpp"
  38 #include "runtime/javaCalls.hpp"
  39 #include "runtime/mutexLocker.hpp"
  40 #include "runtime/os.inline.hpp"
  41 #include "runtime/signature.hpp"
  42 #include "runtime/stubRoutines.hpp"
  43 #include "runtime/thread.inline.hpp"




  44 
  45 // -----------------------------------------------------
  46 // Implementation of JavaCallWrapper
  47 
  48 JavaCallWrapper::JavaCallWrapper(methodHandle callee_method, Handle receiver, JavaValue* result, TRAPS) {
  49   JavaThread* thread = (JavaThread *)THREAD;
  50   bool clear_pending_exception = true;
  51 
  52   guarantee(thread->is_Java_thread(), "crucial check - the VM thread cannot and must not escape to Java code");
  53   assert(!thread->owns_locks(), "must release all locks when leaving VM");
  54   guarantee(!thread->is_Compiler_thread(), "cannot make java calls from the compiler");
  55   _result   = result;
  56 
  57   // Allocate handle block for Java code. This must be done before we change thread_state to _thread_in_Java_or_stub,
  58   // since it can potentially block.
  59   JNIHandleBlock* new_handles = JNIHandleBlock::allocate_block(thread);
  60 
  61   // After this, we are official in JavaCode. This needs to be done before we change any of the thread local
  62   // info, since we cannot find oops before the new information is set up completely.
  63   ThreadStateTransition::transition(thread, _thread_in_vm, _thread_in_Java);
  64 
  65   // Make sure that we handle asynchronous stops and suspends _before_ we clear all thread state
  66   // in JavaCallWrapper::JavaCallWrapper(). This way, we can decide if we need to do any pd actions
  67   // to prepare for stop/suspend (flush register windows on sparcs, cache sp, or other state).
  68   if (thread->has_special_runtime_exit_condition()) {
  69     thread->handle_special_runtime_exit_condition();
  70     if (HAS_PENDING_EXCEPTION) {
  71       clear_pending_exception = false;
  72     }
  73   }
  74 
  75 
  76   // Make sure to set the oop's after the thread transition - since we can block there. No one is GC'ing
  77   // the JavaCallWrapper before the entry frame is on the stack.
  78   _callee_method = callee_method();
  79   _receiver = receiver();
  80 
  81 #ifdef CHECK_UNHANDLED_OOPS
  82   THREAD->allow_unhandled_oop(&_receiver);
  83 #endif // CHECK_UNHANDLED_OOPS
  84 
  85   _thread       = (JavaThread *)thread;
  86   _handles      = _thread->active_handles();    // save previous handle block & Java frame linkage
  87 
  88   // For the profiler, the last_Java_frame information in thread must always be in
  89   // legal state. We have no last Java frame if last_Java_sp == NULL so
  90   // the valid transition is to clear _last_Java_sp and then reset the rest of
  91   // the (platform specific) state.
  92 
  93   _anchor.copy(_thread->frame_anchor());
  94   _thread->frame_anchor()->clear();
  95 
  96   debug_only(_thread->inc_java_call_counter());
  97   _thread->set_active_handles(new_handles);     // install new handle block and reset Java frame linkage
  98 
  99   assert (_thread->thread_state() != _thread_in_native, "cannot set native pc to NULL");
 100 
 101   // clear any pending exception in thread (native calls start with no exception pending)
 102   if(clear_pending_exception) {
 103     _thread->clear_pending_exception();
 104   }
 105 
 106   if (_anchor.last_Java_sp() == NULL) {
 107     _thread->record_base_of_stack_pointer();
 108   }
 109 }
 110 
 111 
 112 JavaCallWrapper::~JavaCallWrapper() {
 113   assert(_thread == JavaThread::current(), "must still be the same thread");
 114 
 115   // restore previous handle block & Java frame linkage
 116   JNIHandleBlock *_old_handles = _thread->active_handles();
 117   _thread->set_active_handles(_handles);
 118 
 119   _thread->frame_anchor()->zap();
 120 
 121   debug_only(_thread->dec_java_call_counter());
 122 
 123   if (_anchor.last_Java_sp() == NULL) {
 124     _thread->set_base_of_stack_pointer(NULL);
 125   }
 126 
 127 
 128   // Old thread-local info. has been restored. We are not back in the VM.
 129   ThreadStateTransition::transition_from_java(_thread, _thread_in_vm);
 130 
 131   // State has been restored now make the anchor frame visible for the profiler.
 132   // Do this after the transition because this allows us to put an assert
 133   // the Java->vm transition which checks to see that stack is not walkable
 134   // on sparc/ia64 which will catch violations of the reseting of last_Java_frame
 135   // invariants (i.e. _flags always cleared on return to Java)
 136 
 137   _thread->frame_anchor()->copy(&_anchor);
 138 
 139   // Release handles after we are marked as being inside the VM again, since this
 140   // operation might block
 141   JNIHandleBlock::release_block(_old_handles, _thread);
 142 }
 143 
 144 
 145 void JavaCallWrapper::oops_do(OopClosure* f) {
 146   f->do_oop((oop*)&_receiver);
 147   handles()->oops_do(f);
 148 }
 149 
 150 
 151 // Helper methods
 152 static BasicType runtime_type_from(JavaValue* result) {
 153   switch (result->get_type()) {
 154     case T_BOOLEAN: // fall through
 155     case T_CHAR   : // fall through
 156     case T_SHORT  : // fall through
 157     case T_INT    : // fall through
 158 #ifndef _LP64
 159     case T_OBJECT : // fall through
 160     case T_ARRAY  : // fall through
 161 #endif
 162     case T_BYTE   : // fall through
 163     case T_VOID   : return T_INT;
 164     case T_LONG   : return T_LONG;
 165     case T_FLOAT  : return T_FLOAT;
 166     case T_DOUBLE : return T_DOUBLE;
 167 #ifdef _LP64
 168     case T_ARRAY  : // fall through
 169     case T_OBJECT:  return T_OBJECT;
 170 #endif
 171   }
 172   ShouldNotReachHere();
 173   return T_ILLEGAL;
 174 }
 175 
 176 // ============ Virtual calls ============
 177 
 178 void JavaCalls::call_virtual(JavaValue* result, KlassHandle spec_klass, Symbol* name, Symbol* signature, JavaCallArguments* args, TRAPS) {
 179   CallInfo callinfo;
 180   Handle receiver = args->receiver();
 181   KlassHandle recvrKlass(THREAD, receiver.is_null() ? (Klass*)NULL : receiver->klass());
 182   LinkInfo link_info(spec_klass, name, signature, KlassHandle(), /*check_access*/false);
 183   LinkResolver::resolve_virtual_call(
 184           callinfo, receiver, recvrKlass, link_info, true, CHECK);
 185   methodHandle method = callinfo.selected_method();
 186   assert(method.not_null(), "should have thrown exception");
 187 
 188   // Invoke the method
 189   JavaCalls::call(result, method, args, CHECK);
 190 }
 191 
 192 
 193 void JavaCalls::call_virtual(JavaValue* result, Handle receiver, KlassHandle spec_klass, Symbol* name, Symbol* signature, TRAPS) {
 194   JavaCallArguments args(receiver); // One oop argument
 195   call_virtual(result, spec_klass, name, signature, &args, CHECK);
 196 }
 197 
 198 
 199 void JavaCalls::call_virtual(JavaValue* result, Handle receiver, KlassHandle spec_klass, Symbol* name, Symbol* signature, Handle arg1, TRAPS) {
 200   JavaCallArguments args(receiver); // One oop argument
 201   args.push_oop(arg1);
 202   call_virtual(result, spec_klass, name, signature, &args, CHECK);
 203 }
 204 
 205 
 206 
 207 void JavaCalls::call_virtual(JavaValue* result, Handle receiver, KlassHandle spec_klass, Symbol* name, Symbol* signature, Handle arg1, Handle arg2, TRAPS) {
 208   JavaCallArguments args(receiver); // One oop argument
 209   args.push_oop(arg1);
 210   args.push_oop(arg2);
 211   call_virtual(result, spec_klass, name, signature, &args, CHECK);
 212 }
 213 
 214 
 215 // ============ Special calls ============
 216 
 217 void JavaCalls::call_special(JavaValue* result, KlassHandle klass, Symbol* name, Symbol* signature, JavaCallArguments* args, TRAPS) {
 218   CallInfo callinfo;
 219   LinkInfo link_info(klass, name, signature, KlassHandle(), /*check_access*/false);
 220   LinkResolver::resolve_special_call(callinfo, link_info, CHECK);
 221   methodHandle method = callinfo.selected_method();
 222   assert(method.not_null(), "should have thrown exception");
 223 
 224   // Invoke the method
 225   JavaCalls::call(result, method, args, CHECK);
 226 }
 227 
 228 
 229 void JavaCalls::call_special(JavaValue* result, Handle receiver, KlassHandle klass, Symbol* name, Symbol* signature, TRAPS) {
 230   JavaCallArguments args(receiver); // One oop argument
 231   call_special(result, klass, name, signature, &args, CHECK);
 232 }
 233 
 234 
 235 void JavaCalls::call_special(JavaValue* result, Handle receiver, KlassHandle klass, Symbol* name, Symbol* signature, Handle arg1, TRAPS) {
 236   JavaCallArguments args(receiver); // One oop argument
 237   args.push_oop(arg1);
 238   call_special(result, klass, name, signature, &args, CHECK);
 239 }
 240 
 241 
 242 void JavaCalls::call_special(JavaValue* result, Handle receiver, KlassHandle klass, Symbol* name, Symbol* signature, Handle arg1, Handle arg2, TRAPS) {
 243   JavaCallArguments args(receiver); // One oop argument
 244   args.push_oop(arg1);
 245   args.push_oop(arg2);
 246   call_special(result, klass, name, signature, &args, CHECK);
 247 }
 248 
 249 
 250 // ============ Static calls ============
 251 
 252 void JavaCalls::call_static(JavaValue* result, KlassHandle klass, Symbol* name, Symbol* signature, JavaCallArguments* args, TRAPS) {
 253   CallInfo callinfo;
 254   LinkInfo link_info(klass, name, signature, KlassHandle(), /*check_access*/false);
 255   LinkResolver::resolve_static_call(callinfo, link_info, true, CHECK);
 256   methodHandle method = callinfo.selected_method();
 257   assert(method.not_null(), "should have thrown exception");
 258 
 259   // Invoke the method
 260   JavaCalls::call(result, method, args, CHECK);
 261 }
 262 
 263 
 264 void JavaCalls::call_static(JavaValue* result, KlassHandle klass, Symbol* name, Symbol* signature, TRAPS) {
 265   JavaCallArguments args; // No argument
 266   call_static(result, klass, name, signature, &args, CHECK);
 267 }
 268 
 269 
 270 void JavaCalls::call_static(JavaValue* result, KlassHandle klass, Symbol* name, Symbol* signature, Handle arg1, TRAPS) {
 271   JavaCallArguments args(arg1); // One oop argument
 272   call_static(result, klass, name, signature, &args, CHECK);
 273 }
 274 
 275 
 276 void JavaCalls::call_static(JavaValue* result, KlassHandle klass, Symbol* name, Symbol* signature, Handle arg1, Handle arg2, TRAPS) {
 277   JavaCallArguments args; // One oop argument
 278   args.push_oop(arg1);
 279   args.push_oop(arg2);
 280   call_static(result, klass, name, signature, &args, CHECK);
 281 }
 282 
 283 
 284 // -------------------------------------------------
 285 // Implementation of JavaCalls (low level)
 286 
 287 
 288 void JavaCalls::call(JavaValue* result, methodHandle method, JavaCallArguments* args, TRAPS) {
 289   // Check if we need to wrap a potential OS exception handler around thread
 290   // This is used for e.g. Win32 structured exception handlers
 291   assert(THREAD->is_Java_thread(), "only JavaThreads can make JavaCalls");
 292   // Need to wrap each and every time, since there might be native code down the
 293   // stack that has installed its own exception handlers
 294   os::os_exception_wrapper(call_helper, result, &method, args, THREAD);
 295 }
 296 
 297 void JavaCalls::call_helper(JavaValue* result, methodHandle* m, JavaCallArguments* args, TRAPS) {
 298   // During dumping, Java execution environment is not fully initialized. Also, Java execution
 299   // may cause undesirable side-effects in the class metadata.
 300   assert(!DumpSharedSpaces, "must not execute Java bytecodes when dumping");
 301 
 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   // Verify the arguments





 313 
 314   if (CheckJNICalls)  {
 315     args->verify(method, result->get_type(), thread);
 316   }
 317   else debug_only(args->verify(method, result->get_type(), thread));



 318 
 319   // Ignore call if method is empty
 320   if (method->is_empty_method()) {
 321     assert(result->get_type() == T_VOID, "an empty method must return a void value");
 322     return;
 323   }
 324 
 325 
 326 #ifdef ASSERT
 327   { InstanceKlass* holder = method->method_holder();
 328     // A klass might not be initialized since JavaCall's might be used during the executing of
 329     // the <clinit>. For example, a Thread.start might start executing on an object that is
 330     // not fully initialized! (bad Java programming style)
 331     assert(holder->is_linked(), "rewriting must have taken place");
 332   }
 333 #endif
 334 
 335 
 336   assert(!thread->is_Compiler_thread(), "cannot compile from the compiler");
 337   if (CompilationPolicy::must_be_compiled(method)) {
 338     CompileBroker::compile_method(method, InvocationEntryBci,
 339                                   CompilationPolicy::policy()->initial_compile_level(),
 340                                   methodHandle(), 0, "must_be_compiled", CHECK);
 341   }
 342 
 343   // Since the call stub sets up like the interpreter we call the from_interpreted_entry
 344   // so we can go compiled via a i2c. Otherwise initial entry method will always
 345   // run interpreted.
 346   address entry_point = method->from_interpreted_entry();
 347   if (JvmtiExport::can_post_interpreter_events() && thread->is_interp_only_mode()) {
 348     entry_point = method->interpreter_entry();
 349   }
 350 
 351   // Figure out if the result value is an oop or not (Note: This is a different value
 352   // than result_type. result_type will be T_INT of oops. (it is about size)
 353   BasicType result_type = runtime_type_from(result);
 354   bool oop_result_flag = (result->get_type() == T_OBJECT || result->get_type() == T_ARRAY);
 355 
 356   // NOTE: if we move the computation of the result_val_address inside
 357   // the call to call_stub, the optimizer produces wrong code.
 358   intptr_t* result_val_address = (intptr_t*)(result->get_value_addr());
 359 
 360   // Find receiver
 361   Handle receiver = (!method->is_static()) ? args->receiver() : Handle();
 362 
 363   // When we reenter Java, we need to reenable the yellow zone which
 364   // might already be disabled when we are in VM.
 365   if (thread->stack_yellow_zone_disabled()) {
 366     thread->reguard_stack();
 367   }
 368 
 369   // Check that there are shadow pages available before changing thread state
 370   // to Java
 371   if (!os::stack_shadow_pages_available(THREAD, method)) {
 372     // Throw stack overflow exception with preinitialized exception.
 373     Exceptions::throw_stack_overflow_exception(THREAD, __FILE__, __LINE__, method);
 374     return;
 375   } else {
 376     // Touch pages checked if the OS needs them to be touched to be mapped.
 377     os::bang_stack_shadow_pages();
 378   }
 379 











 380   // do call
 381   { JavaCallWrapper link(method, receiver, result, CHECK);
 382     { HandleMark hm(thread);  // HandleMark used by HandleMarkCleaner
 383 
 384       StubRoutines::call_stub()(
 385         (address)&link,
 386         // (intptr_t*)&(result->_value), // see NOTE above (compiler problem)
 387         result_val_address,          // see NOTE above (compiler problem)
 388         result_type,
 389         method(),
 390         entry_point,
 391         args->parameters(),
 392         args->size_of_parameters(),
 393         CHECK
 394       );
 395 
 396       result = link.result();  // circumvent MS C++ 5.0 compiler bug (result is clobbered across call)
 397       // Preserve oop return value across possible gc points
 398       if (oop_result_flag) {
 399         thread->set_vm_result((oop) result->get_jobject());
 400       }
 401     }
 402   } // Exit JavaCallWrapper (can block - potential return oop must be preserved)
 403 
 404   // Check if a thread stop or suspend should be executed
 405   // The following assert was not realistic.  Thread.stop can set that bit at any moment.
 406   //assert(!thread->has_special_runtime_exit_condition(), "no async. exceptions should be installed");
 407 
 408   // Restore possible oop return
 409   if (oop_result_flag) {
 410     result->set_jobject((jobject)thread->vm_result());
 411     thread->set_vm_result(NULL);
 412   }
 413 }
 414 
 415 
 416 //--------------------------------------------------------------------------------------
 417 // Implementation of JavaCallArguments
 418 
 419 intptr_t* JavaCallArguments::parameters() {
 420   // First convert all handles to oops
 421   for(int i = 0; i < _size; i++) {
 422     if (_is_oop[i]) {
 423       // Handle conversion
 424       _value[i] = cast_from_oop<intptr_t>(Handle::raw_resolve((oop *)_value[i]));
 425     }
 426   }
 427   // Return argument vector
 428   return _value;
 429 }
 430 
 431 
 432 class SignatureChekker : public SignatureIterator {
 433  private:
 434    bool *_is_oop;
 435    int   _pos;
 436    BasicType _return_type;
 437    intptr_t*   _value;
 438    Thread* _thread;
 439 
 440  public:
 441   bool _is_return;
 442 
 443   SignatureChekker(Symbol* signature, BasicType return_type, bool is_static, bool* is_oop, intptr_t* value, Thread* thread) : SignatureIterator(signature) {
 444     _is_oop = is_oop;
 445     _is_return = false;
 446     _return_type = return_type;
 447     _pos = 0;
 448     _value = value;
 449     _thread = thread;
 450 
 451     if (!is_static) {
 452       check_value(true); // Receiver must be an oop
 453     }
 454   }
 455 
 456   void check_value(bool type) {
 457     guarantee(_is_oop[_pos++] == type, "signature does not match pushed arguments");
 458   }
 459 
 460   void check_doing_return(bool state) { _is_return = state; }
 461 
 462   void check_return_type(BasicType t) {
 463     guarantee(_is_return && t == _return_type, "return type does not match");
 464   }
 465 
 466   void check_int(BasicType t) {
 467     if (_is_return) {
 468       check_return_type(t);
 469       return;
 470     }
 471     check_value(false);
 472   }
 473 
 474   void check_double(BasicType t) { check_long(t); }
 475 
 476   void check_long(BasicType t) {
 477     if (_is_return) {
 478       check_return_type(t);
 479       return;
 480     }
 481 
 482     check_value(false);
 483     check_value(false);
 484   }
 485 
 486   void check_obj(BasicType t) {
 487     if (_is_return) {
 488       check_return_type(t);
 489       return;
 490     }
 491 
 492     // verify handle and the oop pointed to by handle
 493     int p = _pos;
 494     bool bad = false;
 495     // If argument is oop
 496     if (_is_oop[p]) {
 497       intptr_t v = _value[p];
 498       if (v != 0 ) {
 499         size_t t = (size_t)v;
 500         bad = (t < (size_t)os::vm_page_size() ) || !Handle::raw_resolve((oop *)v)->is_oop_or_null(true);
 501         if (CheckJNICalls && bad) {
 502           ReportJNIFatalError((JavaThread*)_thread, "Bad JNI oop argument");
 503         }
 504       }
 505       // for the regular debug case.
 506       assert(!bad, "Bad JNI oop argument");
 507     }
 508 
 509     check_value(true);
 510   }
 511 
 512   void do_bool()                       { check_int(T_BOOLEAN);       }
 513   void do_char()                       { check_int(T_CHAR);          }
 514   void do_float()                      { check_int(T_FLOAT);         }
 515   void do_double()                     { check_double(T_DOUBLE);     }
 516   void do_byte()                       { check_int(T_BYTE);          }
 517   void do_short()                      { check_int(T_SHORT);         }
 518   void do_int()                        { check_int(T_INT);           }
 519   void do_long()                       { check_long(T_LONG);         }
 520   void do_void()                       { check_return_type(T_VOID);  }
 521   void do_object(int begin, int end)   { check_obj(T_OBJECT);        }
 522   void do_array(int begin, int end)    { check_obj(T_OBJECT);        }
 523 };
 524 
 525 
 526 void JavaCallArguments::verify(methodHandle method, BasicType return_type,
 527   Thread *thread) {
 528   guarantee(method->size_of_parameters() == size_of_parameters(), "wrong no. of arguments pushed");
 529 
 530   // Treat T_OBJECT and T_ARRAY as the same
 531   if (return_type == T_ARRAY) return_type = T_OBJECT;
 532 
 533   // Check that oop information is correct
 534   Symbol* signature = method->signature();
 535 
 536   SignatureChekker sc(signature, return_type, method->is_static(),_is_oop, _value, thread);
 537   sc.iterate_parameters();
 538   sc.check_doing_return(true);
 539   sc.iterate_returntype();
 540 }
--- EOF ---