1 /*
   2  * Copyright (c) 1997, 2016, 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 #if INCLUDE_JVMCI
  45 #include "jvmci/jvmciJavaClasses.hpp"
  46 #include "jvmci/jvmciRuntime.hpp"
  47 #endif
  48 
  49 // -----------------------------------------------------
  50 // Implementation of JavaCallWrapper
  51 
  52 JavaCallWrapper::JavaCallWrapper(methodHandle callee_method, Handle receiver, JavaValue* result, TRAPS) {
  53   JavaThread* thread = (JavaThread *)THREAD;
  54   bool clear_pending_exception = true;
  55 
  56   guarantee(thread->is_Java_thread(), "crucial check - the VM thread cannot and must not escape to Java code");
  57   assert(!thread->owns_locks(), "must release all locks when leaving VM");
  58   guarantee(thread->can_call_java(), "cannot make java calls from the native compiler");
  59   _result   = result;
  60 
  61   // Allocate handle block for Java code. This must be done before we change thread_state to _thread_in_Java_or_stub,
  62   // since it can potentially block.
  63   JNIHandleBlock* new_handles = JNIHandleBlock::allocate_block(thread);
  64 
  65   // After this, we are official in JavaCode. This needs to be done before we change any of the thread local
  66   // info, since we cannot find oops before the new information is set up completely.
  67   ThreadStateTransition::transition(thread, _thread_in_vm, _thread_in_Java);
  68 
  69   // Make sure that we handle asynchronous stops and suspends _before_ we clear all thread state
  70   // in JavaCallWrapper::JavaCallWrapper(). This way, we can decide if we need to do any pd actions
  71   // to prepare for stop/suspend (flush register windows on sparcs, cache sp, or other state).
  72   if (thread->has_special_runtime_exit_condition()) {
  73     thread->handle_special_runtime_exit_condition();
  74     if (HAS_PENDING_EXCEPTION) {
  75       clear_pending_exception = false;
  76     }
  77   }
  78 
  79 
  80   // Make sure to set the oop's after the thread transition - since we can block there. No one is GC'ing
  81   // the JavaCallWrapper before the entry frame is on the stack.
  82   _callee_method = callee_method();
  83   _receiver = receiver();
  84 
  85 #ifdef CHECK_UNHANDLED_OOPS
  86   THREAD->allow_unhandled_oop(&_receiver);
  87 #endif // CHECK_UNHANDLED_OOPS
  88 
  89   _thread       = (JavaThread *)thread;
  90   _handles      = _thread->active_handles();    // save previous handle block & Java frame linkage
  91 
  92   // For the profiler, the last_Java_frame information in thread must always be in
  93   // legal state. We have no last Java frame if last_Java_sp == NULL so
  94   // the valid transition is to clear _last_Java_sp and then reset the rest of
  95   // the (platform specific) state.
  96 
  97   _anchor.copy(_thread->frame_anchor());
  98   _thread->frame_anchor()->clear();
  99 
 100   debug_only(_thread->inc_java_call_counter());
 101   _thread->set_active_handles(new_handles);     // install new handle block and reset Java frame linkage
 102 
 103   assert (_thread->thread_state() != _thread_in_native, "cannot set native pc to NULL");
 104 
 105   // clear any pending exception in thread (native calls start with no exception pending)
 106   if(clear_pending_exception) {
 107     _thread->clear_pending_exception();
 108   }
 109 
 110   if (_anchor.last_Java_sp() == NULL) {
 111     _thread->record_base_of_stack_pointer();
 112   }
 113 }
 114 
 115 
 116 JavaCallWrapper::~JavaCallWrapper() {
 117   assert(_thread == JavaThread::current(), "must still be the same thread");
 118 
 119   // restore previous handle block & Java frame linkage
 120   JNIHandleBlock *_old_handles = _thread->active_handles();
 121   _thread->set_active_handles(_handles);
 122 
 123   _thread->frame_anchor()->zap();
 124 
 125   debug_only(_thread->dec_java_call_counter());
 126 
 127   if (_anchor.last_Java_sp() == NULL) {
 128     _thread->set_base_of_stack_pointer(NULL);
 129   }
 130 
 131 
 132   // Old thread-local info. has been restored. We are not back in the VM.
 133   ThreadStateTransition::transition_from_java(_thread, _thread_in_vm);
 134 
 135   // State has been restored now make the anchor frame visible for the profiler.
 136   // Do this after the transition because this allows us to put an assert
 137   // the Java->vm transition which checks to see that stack is not walkable
 138   // on sparc/ia64 which will catch violations of the reseting of last_Java_frame
 139   // invariants (i.e. _flags always cleared on return to Java)
 140 
 141   _thread->frame_anchor()->copy(&_anchor);
 142 
 143   // Release handles after we are marked as being inside the VM again, since this
 144   // operation might block
 145   JNIHandleBlock::release_block(_old_handles, _thread);
 146 }
 147 
 148 
 149 void JavaCallWrapper::oops_do(OopClosure* f) {
 150   f->do_oop((oop*)&_receiver);
 151   handles()->oops_do(f);
 152 }
 153 
 154 
 155 // Helper methods
 156 static BasicType runtime_type_from(JavaValue* result) {
 157   switch (result->get_type()) {
 158     case T_BOOLEAN: // fall through
 159     case T_CHAR   : // fall through
 160     case T_SHORT  : // fall through
 161     case T_INT    : // fall through
 162 #ifndef _LP64
 163     case T_OBJECT : // fall through
 164     case T_ARRAY  : // fall through
 165 #endif
 166     case T_BYTE   : // fall through
 167     case T_VOID   : return T_INT;
 168     case T_LONG   : return T_LONG;
 169     case T_FLOAT  : return T_FLOAT;
 170     case T_DOUBLE : return T_DOUBLE;
 171 #ifdef _LP64
 172     case T_ARRAY  : // fall through
 173     case T_OBJECT:  return T_OBJECT;
 174 #endif
 175   }
 176   ShouldNotReachHere();
 177   return T_ILLEGAL;
 178 }
 179 
 180 // ============ Virtual calls ============
 181 
 182 void JavaCalls::call_virtual(JavaValue* result, KlassHandle spec_klass, Symbol* name, Symbol* signature, JavaCallArguments* args, TRAPS) {
 183   CallInfo callinfo;
 184   Handle receiver = args->receiver();
 185   KlassHandle recvrKlass(THREAD, receiver.is_null() ? (Klass*)NULL : receiver->klass());
 186   LinkInfo link_info(spec_klass, name, signature, KlassHandle(), /*check_access*/false);
 187   LinkResolver::resolve_virtual_call(
 188           callinfo, receiver, recvrKlass, link_info, true, CHECK);
 189   methodHandle method = callinfo.selected_method();
 190   assert(method.not_null(), "should have thrown exception");
 191 
 192   // Invoke the method
 193   JavaCalls::call(result, method, args, CHECK);
 194 }
 195 
 196 
 197 void JavaCalls::call_virtual(JavaValue* result, Handle receiver, KlassHandle spec_klass, Symbol* name, Symbol* signature, TRAPS) {
 198   JavaCallArguments args(receiver); // One oop argument
 199   call_virtual(result, spec_klass, name, signature, &args, CHECK);
 200 }
 201 
 202 
 203 void JavaCalls::call_virtual(JavaValue* result, Handle receiver, KlassHandle spec_klass, Symbol* name, Symbol* signature, Handle arg1, TRAPS) {
 204   JavaCallArguments args(receiver); // One oop argument
 205   args.push_oop(arg1);
 206   call_virtual(result, spec_klass, name, signature, &args, CHECK);
 207 }
 208 
 209 
 210 
 211 void JavaCalls::call_virtual(JavaValue* result, Handle receiver, KlassHandle spec_klass, Symbol* name, Symbol* signature, Handle arg1, Handle arg2, TRAPS) {
 212   JavaCallArguments args(receiver); // One oop argument
 213   args.push_oop(arg1);
 214   args.push_oop(arg2);
 215   call_virtual(result, spec_klass, name, signature, &args, CHECK);
 216 }
 217 
 218 
 219 // ============ Special calls ============
 220 
 221 void JavaCalls::call_special(JavaValue* result, KlassHandle klass, Symbol* name, Symbol* signature, JavaCallArguments* args, TRAPS) {
 222   CallInfo callinfo;
 223   LinkInfo link_info(klass, name, signature, KlassHandle(), /*check_access*/false);
 224   LinkResolver::resolve_special_call(callinfo, link_info, CHECK);
 225   methodHandle method = callinfo.selected_method();
 226   assert(method.not_null(), "should have thrown exception");
 227 
 228   // Invoke the method
 229   JavaCalls::call(result, method, args, CHECK);
 230 }
 231 
 232 
 233 void JavaCalls::call_special(JavaValue* result, Handle receiver, KlassHandle klass, Symbol* name, Symbol* signature, TRAPS) {
 234   JavaCallArguments args(receiver); // One oop argument
 235   call_special(result, klass, name, signature, &args, CHECK);
 236 }
 237 
 238 
 239 void JavaCalls::call_special(JavaValue* result, Handle receiver, KlassHandle klass, Symbol* name, Symbol* signature, Handle arg1, TRAPS) {
 240   JavaCallArguments args(receiver); // One oop argument
 241   args.push_oop(arg1);
 242   call_special(result, klass, name, signature, &args, CHECK);
 243 }
 244 
 245 
 246 void JavaCalls::call_special(JavaValue* result, Handle receiver, KlassHandle klass, Symbol* name, Symbol* signature, Handle arg1, Handle arg2, TRAPS) {
 247   JavaCallArguments args(receiver); // One oop argument
 248   args.push_oop(arg1);
 249   args.push_oop(arg2);
 250   call_special(result, klass, name, signature, &args, CHECK);
 251 }
 252 
 253 
 254 // ============ Static calls ============
 255 
 256 void JavaCalls::call_static(JavaValue* result, KlassHandle klass, Symbol* name, Symbol* signature, JavaCallArguments* args, TRAPS) {
 257   CallInfo callinfo;
 258   LinkInfo link_info(klass, name, signature, KlassHandle(), /*check_access*/false);
 259   LinkResolver::resolve_static_call(callinfo, link_info, 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, Symbol* name, Symbol* 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, Symbol* name, Symbol* 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, Symbol* name, Symbol* 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, const 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 every time, 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, const methodHandle& method, JavaCallArguments* args, TRAPS) {
 302   // During dumping, Java execution environment is not fully initialized. Also, Java execution
 303   // may cause undesirable side-effects in the class metadata.
 304   assert(!DumpSharedSpaces, "must not execute Java bytecodes when dumping");
 305 
 306   JavaThread* thread = (JavaThread*)THREAD;
 307   assert(thread->is_Java_thread(), "must be called by a java thread");
 308   assert(method.not_null(), "must have a method to call");
 309   assert(!SafepointSynchronize::is_at_safepoint(), "call to Java code during VM operation");
 310   assert(!thread->handle_area()->no_handle_mark_active(), "cannot call out to Java here");
 311 
 312 
 313   CHECK_UNHANDLED_OOPS_ONLY(thread->clear_unhandled_oops();)
 314 
 315 #if INCLUDE_JVMCI
 316   // Gets the nmethod (if any) that should be called instead of normal target
 317   nmethod* alternative_target = args->alternative_target();
 318   if (alternative_target == NULL) {
 319 #endif
 320 // Verify the arguments
 321 
 322   if (CheckJNICalls)  {
 323     args->verify(method, result->get_type(), thread);
 324   }
 325   else debug_only(args->verify(method, result->get_type(), thread));
 326 #if INCLUDE_JVMCI
 327   }
 328 #else
 329 
 330   // Ignore call if method is empty
 331   if (method->is_empty_method()) {
 332     assert(result->get_type() == T_VOID, "an empty method must return a void value");
 333     return;
 334   }
 335 #endif
 336 
 337 #ifdef ASSERT
 338   { InstanceKlass* holder = method->method_holder();
 339     // A klass might not be initialized since JavaCall's might be used during the executing of
 340     // the <clinit>. For example, a Thread.start might start executing on an object that is
 341     // not fully initialized! (bad Java programming style)
 342     assert(holder->is_linked(), "rewriting must have taken place");
 343   }
 344 #endif
 345 
 346 
 347   assert(thread->can_call_java(), "cannot compile from the native compiler");
 348   if (CompilationPolicy::must_be_compiled(method)) {
 349     CompileBroker::compile_method(method, InvocationEntryBci,
 350                                   CompilationPolicy::policy()->initial_compile_level(),
 351                                   methodHandle(), 0, "must_be_compiled", CHECK);
 352   }
 353 
 354   // Since the call stub sets up like the interpreter we call the from_interpreted_entry
 355   // so we can go compiled via a i2c. Otherwise initial entry method will always
 356   // run interpreted.
 357   address entry_point = method->from_interpreted_entry();
 358   if (JvmtiExport::can_post_interpreter_events() && thread->is_interp_only_mode()) {
 359     entry_point = method->interpreter_entry();
 360   }
 361 
 362   // Figure out if the result value is an oop or not (Note: This is a different value
 363   // than result_type. result_type will be T_INT of oops. (it is about size)
 364   BasicType result_type = runtime_type_from(result);
 365   bool oop_result_flag = (result->get_type() == T_OBJECT || result->get_type() == T_ARRAY);
 366 
 367   // NOTE: if we move the computation of the result_val_address inside
 368   // the call to call_stub, the optimizer produces wrong code.
 369   intptr_t* result_val_address = (intptr_t*)(result->get_value_addr());
 370 
 371   // Find receiver
 372   Handle receiver = (!method->is_static()) ? args->receiver() : Handle();
 373 
 374   // When we reenter Java, we need to reenable the reserved/yellow zone which
 375   // might already be disabled when we are in VM.
 376   if (!thread->stack_guards_enabled()) {
 377     thread->reguard_stack();
 378   }
 379 
 380   // Check that there are shadow pages available before changing thread state
 381   // to Java
 382   if (!os::stack_shadow_pages_available(THREAD, method)) {
 383     // Throw stack overflow exception with preinitialized exception.
 384     Exceptions::throw_stack_overflow_exception(THREAD, __FILE__, __LINE__, method);
 385     return;
 386   } else {
 387     // Touch pages checked if the OS needs them to be touched to be mapped.
 388     os::map_stack_shadow_pages();
 389   }
 390 
 391 #if INCLUDE_JVMCI
 392   if (alternative_target != NULL) {
 393     if (alternative_target->is_alive()) {
 394       thread->set_jvmci_alternate_call_target(alternative_target->verified_entry_point());
 395       entry_point = method->adapter()->get_i2c_entry();
 396     } else {
 397       THROW(vmSymbols::jdk_vm_ci_code_InvalidInstalledCodeException());
 398     }
 399   }
 400 #endif
 401 
 402   // do call
 403   { JavaCallWrapper link(method, receiver, result, CHECK);
 404     { HandleMark hm(thread);  // HandleMark used by HandleMarkCleaner
 405 
 406       StubRoutines::call_stub()(
 407         (address)&link,
 408         // (intptr_t*)&(result->_value), // see NOTE above (compiler problem)
 409         result_val_address,          // see NOTE above (compiler problem)
 410         result_type,
 411         method(),
 412         entry_point,
 413         args->parameters(),
 414         args->size_of_parameters(),
 415         CHECK
 416       );
 417 
 418       result = link.result();  // circumvent MS C++ 5.0 compiler bug (result is clobbered across call)
 419       // Preserve oop return value across possible gc points
 420       if (oop_result_flag) {
 421         thread->set_vm_result((oop) result->get_jobject());
 422       }
 423     }
 424   } // Exit JavaCallWrapper (can block - potential return oop must be preserved)
 425 
 426   // Check if a thread stop or suspend should be executed
 427   // The following assert was not realistic.  Thread.stop can set that bit at any moment.
 428   //assert(!thread->has_special_runtime_exit_condition(), "no async. exceptions should be installed");
 429 
 430   // Restore possible oop return
 431   if (oop_result_flag) {
 432     result->set_jobject((jobject)thread->vm_result());
 433     thread->set_vm_result(NULL);
 434   }
 435 }
 436 
 437 
 438 //--------------------------------------------------------------------------------------
 439 // Implementation of JavaCallArguments
 440 
 441 intptr_t* JavaCallArguments::parameters() {
 442   // First convert all handles to oops
 443   for(int i = 0; i < _size; i++) {
 444     if (_is_oop[i]) {
 445       // Handle conversion
 446       _value[i] = cast_from_oop<intptr_t>(Handle::raw_resolve((oop *)_value[i]));
 447     }
 448   }
 449   // Return argument vector
 450   return _value;
 451 }
 452 
 453 
 454 class SignatureChekker : public SignatureIterator {
 455  private:
 456    bool *_is_oop;
 457    int   _pos;
 458    BasicType _return_type;
 459    intptr_t*   _value;
 460    Thread* _thread;
 461 
 462  public:
 463   bool _is_return;
 464 
 465   SignatureChekker(Symbol* signature, BasicType return_type, bool is_static, bool* is_oop, intptr_t* value, Thread* thread) : SignatureIterator(signature) {
 466     _is_oop = is_oop;
 467     _is_return = false;
 468     _return_type = return_type;
 469     _pos = 0;
 470     _value = value;
 471     _thread = thread;
 472 
 473     if (!is_static) {
 474       check_value(true); // Receiver must be an oop
 475     }
 476   }
 477 
 478   void check_value(bool type) {
 479     guarantee(_is_oop[_pos++] == type, "signature does not match pushed arguments");
 480   }
 481 
 482   void check_doing_return(bool state) { _is_return = state; }
 483 
 484   void check_return_type(BasicType t) {
 485     guarantee(_is_return && t == _return_type, "return type does not match");
 486   }
 487 
 488   void check_int(BasicType t) {
 489     if (_is_return) {
 490       check_return_type(t);
 491       return;
 492     }
 493     check_value(false);
 494   }
 495 
 496   void check_double(BasicType t) { check_long(t); }
 497 
 498   void check_long(BasicType t) {
 499     if (_is_return) {
 500       check_return_type(t);
 501       return;
 502     }
 503 
 504     check_value(false);
 505     check_value(false);
 506   }
 507 
 508   void check_obj(BasicType t) {
 509     if (_is_return) {
 510       check_return_type(t);
 511       return;
 512     }
 513 
 514     // verify handle and the oop pointed to by handle
 515     int p = _pos;
 516     bool bad = false;
 517     // If argument is oop
 518     if (_is_oop[p]) {
 519       intptr_t v = _value[p];
 520       if (v != 0 ) {
 521         size_t t = (size_t)v;
 522         bad = (t < (size_t)os::vm_page_size() ) || !Handle::raw_resolve((oop *)v)->is_oop_or_null(true);
 523         if (CheckJNICalls && bad) {
 524           ReportJNIFatalError((JavaThread*)_thread, "Bad JNI oop argument");
 525         }
 526       }
 527       // for the regular debug case.
 528       assert(!bad, "Bad JNI oop argument");
 529     }
 530 
 531     check_value(true);
 532   }
 533 
 534   void do_bool()                       { check_int(T_BOOLEAN);       }
 535   void do_char()                       { check_int(T_CHAR);          }
 536   void do_float()                      { check_int(T_FLOAT);         }
 537   void do_double()                     { check_double(T_DOUBLE);     }
 538   void do_byte()                       { check_int(T_BYTE);          }
 539   void do_short()                      { check_int(T_SHORT);         }
 540   void do_int()                        { check_int(T_INT);           }
 541   void do_long()                       { check_long(T_LONG);         }
 542   void do_void()                       { check_return_type(T_VOID);  }
 543   void do_object(int begin, int end)   { check_obj(T_OBJECT);        }
 544   void do_array(int begin, int end)    { check_obj(T_OBJECT);        }
 545 };
 546 
 547 
 548 void JavaCallArguments::verify(const methodHandle& method, BasicType return_type,
 549   Thread *thread) {
 550   guarantee(method->size_of_parameters() == size_of_parameters(), "wrong no. of arguments pushed");
 551 
 552   // Treat T_OBJECT and T_ARRAY as the same
 553   if (return_type == T_ARRAY) return_type = T_OBJECT;
 554 
 555   // Check that oop information is correct
 556   Symbol* signature = method->signature();
 557 
 558   SignatureChekker sc(signature, return_type, method->is_static(),_is_oop, _value, thread);
 559   sc.iterate_parameters();
 560   sc.check_doing_return(true);
 561   sc.iterate_returntype();
 562 }