1 /*
   2  * Copyright (c) 1999, 2019, 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 "asm/codeBuffer.hpp"
  27 #include "c1/c1_CodeStubs.hpp"
  28 #include "c1/c1_Defs.hpp"
  29 #include "c1/c1_FrameMap.hpp"
  30 #include "c1/c1_LIRAssembler.hpp"
  31 #include "c1/c1_MacroAssembler.hpp"
  32 #include "c1/c1_Runtime1.hpp"
  33 #include "classfile/systemDictionary.hpp"
  34 #include "classfile/vmSymbols.hpp"
  35 #include "code/codeBlob.hpp"
  36 #include "code/compiledIC.hpp"
  37 #include "code/pcDesc.hpp"
  38 #include "code/scopeDesc.hpp"
  39 #include "code/vtableStubs.hpp"
  40 #include "compiler/disassembler.hpp"
  41 #include "gc/shared/barrierSet.hpp"
  42 #include "gc/shared/c1/barrierSetC1.hpp"
  43 #include "gc/shared/collectedHeap.hpp"
  44 #include "interpreter/bytecode.hpp"
  45 #include "interpreter/interpreter.hpp"
  46 #include "jfr/support/jfrIntrinsics.hpp"
  47 #include "logging/log.hpp"
  48 #include "memory/allocation.inline.hpp"
  49 #include "memory/oopFactory.hpp"
  50 #include "memory/resourceArea.hpp"
  51 #include "memory/universe.hpp"
  52 #include "oops/access.inline.hpp"
  53 #include "oops/objArrayOop.inline.hpp"
  54 #include "oops/objArrayKlass.hpp"
  55 #include "oops/oop.inline.hpp"
  56 #include "runtime/atomic.hpp"
  57 #include "runtime/biasedLocking.hpp"
  58 #include "runtime/compilationPolicy.hpp"
  59 #include "runtime/fieldDescriptor.inline.hpp"
  60 #include "runtime/frame.inline.hpp"
  61 #include "runtime/handles.inline.hpp"
  62 #include "runtime/interfaceSupport.inline.hpp"
  63 #include "runtime/javaCalls.hpp"
  64 #include "runtime/sharedRuntime.hpp"
  65 #include "runtime/threadCritical.hpp"
  66 #include "runtime/vframe.inline.hpp"
  67 #include "runtime/vframeArray.hpp"
  68 #include "runtime/vm_version.hpp"
  69 #include "utilities/copy.hpp"
  70 #include "utilities/events.hpp"
  71 
  72 
  73 // Implementation of StubAssembler
  74 
  75 StubAssembler::StubAssembler(CodeBuffer* code, const char * name, int stub_id) : C1_MacroAssembler(code) {
  76   _name = name;
  77   _must_gc_arguments = false;
  78   _frame_size = no_frame_size;
  79   _num_rt_args = 0;
  80   _stub_id = stub_id;
  81 }
  82 
  83 
  84 void StubAssembler::set_info(const char* name, bool must_gc_arguments) {
  85   _name = name;
  86   _must_gc_arguments = must_gc_arguments;
  87 }
  88 
  89 
  90 void StubAssembler::set_frame_size(int size) {
  91   if (_frame_size == no_frame_size) {
  92     _frame_size = size;
  93   }
  94   assert(_frame_size == size, "can't change the frame size");
  95 }
  96 
  97 
  98 void StubAssembler::set_num_rt_args(int args) {
  99   if (_num_rt_args == 0) {
 100     _num_rt_args = args;
 101   }
 102   assert(_num_rt_args == args, "can't change the number of args");
 103 }
 104 
 105 // Implementation of Runtime1
 106 
 107 CodeBlob* Runtime1::_blobs[Runtime1::number_of_ids];
 108 const char *Runtime1::_blob_names[] = {
 109   RUNTIME1_STUBS(STUB_NAME, LAST_STUB_NAME)
 110 };
 111 
 112 #ifndef PRODUCT
 113 // statistics
 114 int Runtime1::_generic_arraycopy_cnt = 0;
 115 int Runtime1::_generic_arraycopystub_cnt = 0;
 116 int Runtime1::_arraycopy_slowcase_cnt = 0;
 117 int Runtime1::_arraycopy_checkcast_cnt = 0;
 118 int Runtime1::_arraycopy_checkcast_attempt_cnt = 0;
 119 int Runtime1::_new_type_array_slowcase_cnt = 0;
 120 int Runtime1::_new_object_array_slowcase_cnt = 0;
 121 int Runtime1::_new_instance_slowcase_cnt = 0;
 122 int Runtime1::_new_multi_array_slowcase_cnt = 0;
 123 int Runtime1::_monitorenter_slowcase_cnt = 0;
 124 int Runtime1::_monitorexit_slowcase_cnt = 0;
 125 int Runtime1::_patch_code_slowcase_cnt = 0;
 126 int Runtime1::_throw_range_check_exception_count = 0;
 127 int Runtime1::_throw_index_exception_count = 0;
 128 int Runtime1::_throw_div0_exception_count = 0;
 129 int Runtime1::_throw_null_pointer_exception_count = 0;
 130 int Runtime1::_throw_class_cast_exception_count = 0;
 131 int Runtime1::_throw_incompatible_class_change_error_count = 0;
 132 int Runtime1::_throw_array_store_exception_count = 0;
 133 int Runtime1::_throw_count = 0;
 134 
 135 static int _byte_arraycopy_stub_cnt = 0;
 136 static int _short_arraycopy_stub_cnt = 0;
 137 static int _int_arraycopy_stub_cnt = 0;
 138 static int _long_arraycopy_stub_cnt = 0;
 139 static int _oop_arraycopy_stub_cnt = 0;
 140 
 141 address Runtime1::arraycopy_count_address(BasicType type) {
 142   switch (type) {
 143   case T_BOOLEAN:
 144   case T_BYTE:   return (address)&_byte_arraycopy_stub_cnt;
 145   case T_CHAR:
 146   case T_SHORT:  return (address)&_short_arraycopy_stub_cnt;
 147   case T_FLOAT:
 148   case T_INT:    return (address)&_int_arraycopy_stub_cnt;
 149   case T_DOUBLE:
 150   case T_LONG:   return (address)&_long_arraycopy_stub_cnt;
 151   case T_ARRAY:
 152   case T_OBJECT: return (address)&_oop_arraycopy_stub_cnt;
 153   default:
 154     ShouldNotReachHere();
 155     return NULL;
 156   }
 157 }
 158 
 159 
 160 #endif
 161 
 162 // Simple helper to see if the caller of a runtime stub which
 163 // entered the VM has been deoptimized
 164 
 165 static bool caller_is_deopted() {
 166   JavaThread* thread = JavaThread::current();
 167   RegisterMap reg_map(thread, false);
 168   frame runtime_frame = thread->last_frame();
 169   frame caller_frame = runtime_frame.sender(&reg_map);
 170   assert(caller_frame.is_compiled_frame(), "must be compiled");
 171   return caller_frame.is_deoptimized_frame();
 172 }
 173 
 174 // Stress deoptimization
 175 static void deopt_caller() {
 176   if ( !caller_is_deopted()) {
 177     JavaThread* thread = JavaThread::current();
 178     RegisterMap reg_map(thread, false);
 179     frame runtime_frame = thread->last_frame();
 180     frame caller_frame = runtime_frame.sender(&reg_map);
 181     Deoptimization::deoptimize_frame(thread, caller_frame.id());
 182     assert(caller_is_deopted(), "Must be deoptimized");
 183   }
 184 }
 185 
 186 class StubIDStubAssemblerCodeGenClosure: public StubAssemblerCodeGenClosure {
 187  private:
 188   Runtime1::StubID _id;
 189  public:
 190   StubIDStubAssemblerCodeGenClosure(Runtime1::StubID id) : _id(id) {}
 191   virtual OopMapSet* generate_code(StubAssembler* sasm) {
 192     return Runtime1::generate_code_for(_id, sasm);
 193   }
 194 };
 195 
 196 CodeBlob* Runtime1::generate_blob(BufferBlob* buffer_blob, int stub_id, const char* name, bool expect_oop_map, StubAssemblerCodeGenClosure* cl) {
 197   ResourceMark rm;
 198   // create code buffer for code storage
 199   CodeBuffer code(buffer_blob);
 200 
 201   OopMapSet* oop_maps;
 202   int frame_size;
 203   bool must_gc_arguments;
 204 
 205   Compilation::setup_code_buffer(&code, 0);
 206 
 207   // create assembler for code generation
 208   StubAssembler* sasm = new StubAssembler(&code, name, stub_id);
 209   // generate code for runtime stub
 210   oop_maps = cl->generate_code(sasm);
 211   assert(oop_maps == NULL || sasm->frame_size() != no_frame_size,
 212          "if stub has an oop map it must have a valid frame size");
 213   assert(!expect_oop_map || oop_maps != NULL, "must have an oopmap");
 214 
 215   // align so printing shows nop's instead of random code at the end (SimpleStubs are aligned)
 216   sasm->align(BytesPerWord);
 217   // make sure all code is in code buffer
 218   sasm->flush();
 219 
 220   frame_size = sasm->frame_size();
 221   must_gc_arguments = sasm->must_gc_arguments();
 222   // create blob - distinguish a few special cases
 223   CodeBlob* blob = RuntimeStub::new_runtime_stub(name,
 224                                                  &code,
 225                                                  CodeOffsets::frame_never_safe,
 226                                                  frame_size,
 227                                                  oop_maps,
 228                                                  must_gc_arguments);
 229   assert(blob != NULL, "blob must exist");
 230   return blob;
 231 }
 232 
 233 void Runtime1::generate_blob_for(BufferBlob* buffer_blob, StubID id) {
 234   assert(0 <= id && id < number_of_ids, "illegal stub id");
 235   bool expect_oop_map = true;
 236 #ifdef ASSERT
 237   // Make sure that stubs that need oopmaps have them
 238   switch (id) {
 239     // These stubs don't need to have an oopmap
 240   case dtrace_object_alloc_id:
 241   case slow_subtype_check_id:
 242   case fpu2long_stub_id:
 243   case unwind_exception_id:
 244   case counter_overflow_id:
 245 #if defined(SPARC) || defined(PPC32)
 246   case handle_exception_nofpu_id:  // Unused on sparc
 247 #endif
 248     expect_oop_map = false;
 249     break;
 250   default:
 251     break;
 252   }
 253 #endif
 254   StubIDStubAssemblerCodeGenClosure cl(id);
 255   CodeBlob* blob = generate_blob(buffer_blob, id, name_for(id), expect_oop_map, &cl);
 256   // install blob
 257   _blobs[id] = blob;
 258 }
 259 
 260 void Runtime1::initialize(BufferBlob* blob) {
 261   // platform-dependent initialization
 262   initialize_pd();
 263   // generate stubs
 264   for (int id = 0; id < number_of_ids; id++) generate_blob_for(blob, (StubID)id);
 265   // printing
 266 #ifndef PRODUCT
 267   if (PrintSimpleStubs) {
 268     ResourceMark rm;
 269     for (int id = 0; id < number_of_ids; id++) {
 270       _blobs[id]->print();
 271       if (_blobs[id]->oop_maps() != NULL) {
 272         _blobs[id]->oop_maps()->print();
 273       }
 274     }
 275   }
 276 #endif
 277   BarrierSetC1* bs = BarrierSet::barrier_set()->barrier_set_c1();
 278   bs->generate_c1_runtime_stubs(blob);
 279 }
 280 
 281 CodeBlob* Runtime1::blob_for(StubID id) {
 282   assert(0 <= id && id < number_of_ids, "illegal stub id");
 283   return _blobs[id];
 284 }
 285 
 286 
 287 const char* Runtime1::name_for(StubID id) {
 288   assert(0 <= id && id < number_of_ids, "illegal stub id");
 289   return _blob_names[id];
 290 }
 291 
 292 const char* Runtime1::name_for_address(address entry) {
 293   for (int id = 0; id < number_of_ids; id++) {
 294     if (entry == entry_for((StubID)id)) return name_for((StubID)id);
 295   }
 296 
 297   BarrierSetC1* bsc1 = BarrierSet::barrier_set()->barrier_set_c1();
 298   const char* name = bsc1->rtcall_name_for_address(entry);
 299   if (name != NULL) {
 300     return name;
 301   }
 302 
 303 #define FUNCTION_CASE(a, f) \
 304   if ((intptr_t)a == CAST_FROM_FN_PTR(intptr_t, f))  return #f
 305 
 306   FUNCTION_CASE(entry, os::javaTimeMillis);
 307   FUNCTION_CASE(entry, os::javaTimeNanos);
 308   FUNCTION_CASE(entry, SharedRuntime::OSR_migration_end);
 309   FUNCTION_CASE(entry, SharedRuntime::d2f);
 310   FUNCTION_CASE(entry, SharedRuntime::d2i);
 311   FUNCTION_CASE(entry, SharedRuntime::d2l);
 312   FUNCTION_CASE(entry, SharedRuntime::dcos);
 313   FUNCTION_CASE(entry, SharedRuntime::dexp);
 314   FUNCTION_CASE(entry, SharedRuntime::dlog);
 315   FUNCTION_CASE(entry, SharedRuntime::dlog10);
 316   FUNCTION_CASE(entry, SharedRuntime::dpow);
 317   FUNCTION_CASE(entry, SharedRuntime::drem);
 318   FUNCTION_CASE(entry, SharedRuntime::dsin);
 319   FUNCTION_CASE(entry, SharedRuntime::dtan);
 320   FUNCTION_CASE(entry, SharedRuntime::f2i);
 321   FUNCTION_CASE(entry, SharedRuntime::f2l);
 322   FUNCTION_CASE(entry, SharedRuntime::frem);
 323   FUNCTION_CASE(entry, SharedRuntime::l2d);
 324   FUNCTION_CASE(entry, SharedRuntime::l2f);
 325   FUNCTION_CASE(entry, SharedRuntime::ldiv);
 326   FUNCTION_CASE(entry, SharedRuntime::lmul);
 327   FUNCTION_CASE(entry, SharedRuntime::lrem);
 328   FUNCTION_CASE(entry, SharedRuntime::lrem);
 329   FUNCTION_CASE(entry, SharedRuntime::dtrace_method_entry);
 330   FUNCTION_CASE(entry, SharedRuntime::dtrace_method_exit);
 331   FUNCTION_CASE(entry, is_instance_of);
 332   FUNCTION_CASE(entry, trace_block_entry);
 333 #ifdef JFR_HAVE_INTRINSICS
 334   FUNCTION_CASE(entry, JFR_TIME_FUNCTION);
 335 #endif
 336   FUNCTION_CASE(entry, StubRoutines::updateBytesCRC32());
 337   FUNCTION_CASE(entry, StubRoutines::updateBytesCRC32C());
 338   FUNCTION_CASE(entry, StubRoutines::vectorizedMismatch());
 339   FUNCTION_CASE(entry, StubRoutines::dexp());
 340   FUNCTION_CASE(entry, StubRoutines::dlog());
 341   FUNCTION_CASE(entry, StubRoutines::dlog10());
 342   FUNCTION_CASE(entry, StubRoutines::dpow());
 343   FUNCTION_CASE(entry, StubRoutines::dsin());
 344   FUNCTION_CASE(entry, StubRoutines::dcos());
 345   FUNCTION_CASE(entry, StubRoutines::dtan());
 346 
 347 #undef FUNCTION_CASE
 348 
 349   // Soft float adds more runtime names.
 350   return pd_name_for_address(entry);
 351 }
 352 
 353 
 354 JRT_ENTRY(void, Runtime1::new_instance(JavaThread* thread, Klass* klass))
 355   NOT_PRODUCT(_new_instance_slowcase_cnt++;)
 356 
 357   assert(klass->is_klass(), "not a class");
 358   Handle holder(THREAD, klass->klass_holder()); // keep the klass alive
 359   InstanceKlass* h = InstanceKlass::cast(klass);
 360   h->check_valid_for_instantiation(true, CHECK);
 361   // make sure klass is initialized
 362   h->initialize(CHECK);
 363   // allocate instance and return via TLS
 364   oop obj = h->allocate_instance(CHECK);
 365   thread->set_vm_result(obj);
 366 JRT_END
 367 
 368 
 369 JRT_ENTRY(void, Runtime1::new_type_array(JavaThread* thread, Klass* klass, jint length))
 370   NOT_PRODUCT(_new_type_array_slowcase_cnt++;)
 371   // Note: no handle for klass needed since they are not used
 372   //       anymore after new_typeArray() and no GC can happen before.
 373   //       (This may have to change if this code changes!)
 374   assert(klass->is_klass(), "not a class");
 375   BasicType elt_type = TypeArrayKlass::cast(klass)->element_type();
 376   oop obj = oopFactory::new_typeArray(elt_type, length, CHECK);
 377   thread->set_vm_result(obj);
 378   // This is pretty rare but this runtime patch is stressful to deoptimization
 379   // if we deoptimize here so force a deopt to stress the path.
 380   if (DeoptimizeALot) {
 381     deopt_caller();
 382   }
 383 
 384 JRT_END
 385 
 386 
 387 JRT_ENTRY(void, Runtime1::new_object_array(JavaThread* thread, Klass* array_klass, jint length))
 388   NOT_PRODUCT(_new_object_array_slowcase_cnt++;)
 389 
 390   // Note: no handle for klass needed since they are not used
 391   //       anymore after new_objArray() and no GC can happen before.
 392   //       (This may have to change if this code changes!)
 393   assert(array_klass->is_klass(), "not a class");
 394   Handle holder(THREAD, array_klass->klass_holder()); // keep the klass alive
 395   Klass* elem_klass = ObjArrayKlass::cast(array_klass)->element_klass();
 396   objArrayOop obj = oopFactory::new_objArray(elem_klass, length, CHECK);
 397   thread->set_vm_result(obj);
 398   // This is pretty rare but this runtime patch is stressful to deoptimization
 399   // if we deoptimize here so force a deopt to stress the path.
 400   if (DeoptimizeALot) {
 401     deopt_caller();
 402   }
 403 JRT_END
 404 
 405 
 406 JRT_ENTRY(void, Runtime1::new_multi_array(JavaThread* thread, Klass* klass, int rank, jint* dims))
 407   NOT_PRODUCT(_new_multi_array_slowcase_cnt++;)
 408 
 409   assert(klass->is_klass(), "not a class");
 410   assert(rank >= 1, "rank must be nonzero");
 411   Handle holder(THREAD, klass->klass_holder()); // keep the klass alive
 412   oop obj = ArrayKlass::cast(klass)->multi_allocate(rank, dims, CHECK);
 413   thread->set_vm_result(obj);
 414 JRT_END
 415 
 416 
 417 JRT_ENTRY(void, Runtime1::unimplemented_entry(JavaThread* thread, StubID id))
 418   tty->print_cr("Runtime1::entry_for(%d) returned unimplemented entry point", id);
 419 JRT_END
 420 
 421 
 422 JRT_ENTRY(void, Runtime1::throw_array_store_exception(JavaThread* thread, oopDesc* obj))
 423   ResourceMark rm(thread);
 424   const char* klass_name = obj->klass()->external_name();
 425   SharedRuntime::throw_and_post_jvmti_exception(thread, vmSymbols::java_lang_ArrayStoreException(), klass_name);
 426 JRT_END
 427 
 428 
 429 // counter_overflow() is called from within C1-compiled methods. The enclosing method is the method
 430 // associated with the top activation record. The inlinee (that is possibly included in the enclosing
 431 // method) method oop is passed as an argument. In order to do that it is embedded in the code as
 432 // a constant.
 433 static nmethod* counter_overflow_helper(JavaThread* THREAD, int branch_bci, Method* m) {
 434   nmethod* osr_nm = NULL;
 435   methodHandle method(THREAD, m);
 436 
 437   RegisterMap map(THREAD, false);
 438   frame fr =  THREAD->last_frame().sender(&map);
 439   nmethod* nm = (nmethod*) fr.cb();
 440   assert(nm!= NULL && nm->is_nmethod(), "Sanity check");
 441   methodHandle enclosing_method(THREAD, nm->method());
 442 
 443   CompLevel level = (CompLevel)nm->comp_level();
 444   int bci = InvocationEntryBci;
 445   if (branch_bci != InvocationEntryBci) {
 446     // Compute destination bci
 447     address pc = method()->code_base() + branch_bci;
 448     Bytecodes::Code branch = Bytecodes::code_at(method(), pc);
 449     int offset = 0;
 450     switch (branch) {
 451       case Bytecodes::_if_icmplt: case Bytecodes::_iflt:
 452       case Bytecodes::_if_icmpgt: case Bytecodes::_ifgt:
 453       case Bytecodes::_if_icmple: case Bytecodes::_ifle:
 454       case Bytecodes::_if_icmpge: case Bytecodes::_ifge:
 455       case Bytecodes::_if_icmpeq: case Bytecodes::_if_acmpeq: case Bytecodes::_ifeq:
 456       case Bytecodes::_if_icmpne: case Bytecodes::_if_acmpne: case Bytecodes::_ifne:
 457       case Bytecodes::_ifnull: case Bytecodes::_ifnonnull: case Bytecodes::_goto:
 458         offset = (int16_t)Bytes::get_Java_u2(pc + 1);
 459         break;
 460       case Bytecodes::_goto_w:
 461         offset = Bytes::get_Java_u4(pc + 1);
 462         break;
 463       default: ;
 464     }
 465     bci = branch_bci + offset;
 466   }
 467   assert(!HAS_PENDING_EXCEPTION, "Should not have any exceptions pending");
 468   osr_nm = CompilationPolicy::policy()->event(enclosing_method, method, branch_bci, bci, level, nm, THREAD);
 469   assert(!HAS_PENDING_EXCEPTION, "Event handler should not throw any exceptions");
 470   return osr_nm;
 471 }
 472 
 473 JRT_BLOCK_ENTRY(address, Runtime1::counter_overflow(JavaThread* thread, int bci, Method* method))
 474   nmethod* osr_nm;
 475   JRT_BLOCK
 476     osr_nm = counter_overflow_helper(thread, bci, method);
 477     if (osr_nm != NULL) {
 478       RegisterMap map(thread, false);
 479       frame fr =  thread->last_frame().sender(&map);
 480       Deoptimization::deoptimize_frame(thread, fr.id());
 481     }
 482   JRT_BLOCK_END
 483   return NULL;
 484 JRT_END
 485 
 486 extern void vm_exit(int code);
 487 
 488 // Enter this method from compiled code handler below. This is where we transition
 489 // to VM mode. This is done as a helper routine so that the method called directly
 490 // from compiled code does not have to transition to VM. This allows the entry
 491 // method to see if the nmethod that we have just looked up a handler for has
 492 // been deoptimized while we were in the vm. This simplifies the assembly code
 493 // cpu directories.
 494 //
 495 // We are entering here from exception stub (via the entry method below)
 496 // If there is a compiled exception handler in this method, we will continue there;
 497 // otherwise we will unwind the stack and continue at the caller of top frame method
 498 // Note: we enter in Java using a special JRT wrapper. This wrapper allows us to
 499 // control the area where we can allow a safepoint. After we exit the safepoint area we can
 500 // check to see if the handler we are going to return is now in a nmethod that has
 501 // been deoptimized. If that is the case we return the deopt blob
 502 // unpack_with_exception entry instead. This makes life for the exception blob easier
 503 // because making that same check and diverting is painful from assembly language.
 504 JRT_ENTRY_NO_ASYNC(static address, exception_handler_for_pc_helper(JavaThread* thread, oopDesc* ex, address pc, nmethod*& nm))
 505   // Reset method handle flag.
 506   thread->set_is_method_handle_return(false);
 507 
 508   Handle exception(thread, ex);
 509   nm = CodeCache::find_nmethod(pc);
 510   assert(nm != NULL, "this is not an nmethod");
 511   // Adjust the pc as needed/
 512   if (nm->is_deopt_pc(pc)) {
 513     RegisterMap map(thread, false);
 514     frame exception_frame = thread->last_frame().sender(&map);
 515     // if the frame isn't deopted then pc must not correspond to the caller of last_frame
 516     assert(exception_frame.is_deoptimized_frame(), "must be deopted");
 517     pc = exception_frame.pc();
 518   }
 519 #ifdef ASSERT
 520   assert(exception.not_null(), "NULL exceptions should be handled by throw_exception");
 521   // Check that exception is a subclass of Throwable, otherwise we have a VerifyError
 522   if (!(exception->is_a(SystemDictionary::Throwable_klass()))) {
 523     if (ExitVMOnVerifyError) vm_exit(-1);
 524     ShouldNotReachHere();
 525   }
 526 #endif
 527 
 528   // Check the stack guard pages and reenable them if necessary and there is
 529   // enough space on the stack to do so.  Use fast exceptions only if the guard
 530   // pages are enabled.
 531   bool guard_pages_enabled = thread->stack_guards_enabled();
 532   if (!guard_pages_enabled) guard_pages_enabled = thread->reguard_stack();
 533 
 534   if (JvmtiExport::can_post_on_exceptions()) {
 535     // To ensure correct notification of exception catches and throws
 536     // we have to deoptimize here.  If we attempted to notify the
 537     // catches and throws during this exception lookup it's possible
 538     // we could deoptimize on the way out of the VM and end back in
 539     // the interpreter at the throw site.  This would result in double
 540     // notifications since the interpreter would also notify about
 541     // these same catches and throws as it unwound the frame.
 542 
 543     RegisterMap reg_map(thread);
 544     frame stub_frame = thread->last_frame();
 545     frame caller_frame = stub_frame.sender(&reg_map);
 546 
 547     // We don't really want to deoptimize the nmethod itself since we
 548     // can actually continue in the exception handler ourselves but I
 549     // don't see an easy way to have the desired effect.
 550     Deoptimization::deoptimize_frame(thread, caller_frame.id());
 551     assert(caller_is_deopted(), "Must be deoptimized");
 552 
 553     return SharedRuntime::deopt_blob()->unpack_with_exception_in_tls();
 554   }
 555 
 556   // ExceptionCache is used only for exceptions at call sites and not for implicit exceptions
 557   if (guard_pages_enabled) {
 558     address fast_continuation = nm->handler_for_exception_and_pc(exception, pc);
 559     if (fast_continuation != NULL) {
 560       // Set flag if return address is a method handle call site.
 561       thread->set_is_method_handle_return(nm->is_method_handle_return(pc));
 562       return fast_continuation;
 563     }
 564   }
 565 
 566   // If the stack guard pages are enabled, check whether there is a handler in
 567   // the current method.  Otherwise (guard pages disabled), force an unwind and
 568   // skip the exception cache update (i.e., just leave continuation==NULL).
 569   address continuation = NULL;
 570   if (guard_pages_enabled) {
 571 
 572     // New exception handling mechanism can support inlined methods
 573     // with exception handlers since the mappings are from PC to PC
 574 
 575     // debugging support
 576     // tracing
 577     if (log_is_enabled(Info, exceptions)) {
 578       ResourceMark rm;
 579       stringStream tempst;
 580       assert(nm->method() != NULL, "Unexpected NULL method()");
 581       tempst.print("compiled method <%s>\n"
 582                    " at PC" INTPTR_FORMAT " for thread " INTPTR_FORMAT,
 583                    nm->method()->print_value_string(), p2i(pc), p2i(thread));
 584       Exceptions::log_exception(exception, tempst.as_string());
 585     }
 586     // for AbortVMOnException flag
 587     Exceptions::debug_check_abort(exception);
 588 
 589     // Clear out the exception oop and pc since looking up an
 590     // exception handler can cause class loading, which might throw an
 591     // exception and those fields are expected to be clear during
 592     // normal bytecode execution.
 593     thread->clear_exception_oop_and_pc();
 594 
 595     bool recursive_exception = false;
 596     continuation = SharedRuntime::compute_compiled_exc_handler(nm, pc, exception, false, false, recursive_exception);
 597     // If an exception was thrown during exception dispatch, the exception oop may have changed
 598     thread->set_exception_oop(exception());
 599     thread->set_exception_pc(pc);
 600 
 601     // the exception cache is used only by non-implicit exceptions
 602     // Update the exception cache only when there didn't happen
 603     // another exception during the computation of the compiled
 604     // exception handler. Checking for exception oop equality is not
 605     // sufficient because some exceptions are pre-allocated and reused.
 606     if (continuation != NULL && !recursive_exception) {
 607       nm->add_handler_for_exception_and_pc(exception, pc, continuation);
 608     }
 609   }
 610 
 611   thread->set_vm_result(exception());
 612   // Set flag if return address is a method handle call site.
 613   thread->set_is_method_handle_return(nm->is_method_handle_return(pc));
 614 
 615   if (log_is_enabled(Info, exceptions)) {
 616     ResourceMark rm;
 617     log_info(exceptions)("Thread " PTR_FORMAT " continuing at PC " PTR_FORMAT
 618                          " for exception thrown at PC " PTR_FORMAT,
 619                          p2i(thread), p2i(continuation), p2i(pc));
 620   }
 621 
 622   return continuation;
 623 JRT_END
 624 
 625 // Enter this method from compiled code only if there is a Java exception handler
 626 // in the method handling the exception.
 627 // We are entering here from exception stub. We don't do a normal VM transition here.
 628 // We do it in a helper. This is so we can check to see if the nmethod we have just
 629 // searched for an exception handler has been deoptimized in the meantime.
 630 address Runtime1::exception_handler_for_pc(JavaThread* thread) {
 631   oop exception = thread->exception_oop();
 632   address pc = thread->exception_pc();
 633   // Still in Java mode
 634   DEBUG_ONLY(ResetNoHandleMark rnhm);
 635   nmethod* nm = NULL;
 636   address continuation = NULL;
 637   {
 638     // Enter VM mode by calling the helper
 639     ResetNoHandleMark rnhm;
 640     continuation = exception_handler_for_pc_helper(thread, exception, pc, nm);
 641   }
 642   // Back in JAVA, use no oops DON'T safepoint
 643 
 644   // Now check to see if the nmethod we were called from is now deoptimized.
 645   // If so we must return to the deopt blob and deoptimize the nmethod
 646   if (nm != NULL && caller_is_deopted()) {
 647     continuation = SharedRuntime::deopt_blob()->unpack_with_exception_in_tls();
 648   }
 649 
 650   assert(continuation != NULL, "no handler found");
 651   return continuation;
 652 }
 653 
 654 
 655 JRT_ENTRY(void, Runtime1::throw_range_check_exception(JavaThread* thread, int index, arrayOopDesc* a))
 656   NOT_PRODUCT(_throw_range_check_exception_count++;)
 657   const int len = 35;
 658   assert(len < strlen("Index %d out of bounds for length %d"), "Must allocate more space for message.");
 659   char message[2 * jintAsStringSize + len];
 660   sprintf(message, "Index %d out of bounds for length %d", index, a->length());
 661   SharedRuntime::throw_and_post_jvmti_exception(thread, vmSymbols::java_lang_ArrayIndexOutOfBoundsException(), message);
 662 JRT_END
 663 
 664 
 665 JRT_ENTRY(void, Runtime1::throw_index_exception(JavaThread* thread, int index))
 666   NOT_PRODUCT(_throw_index_exception_count++;)
 667   char message[16];
 668   sprintf(message, "%d", index);
 669   SharedRuntime::throw_and_post_jvmti_exception(thread, vmSymbols::java_lang_IndexOutOfBoundsException(), message);
 670 JRT_END
 671 
 672 
 673 JRT_ENTRY(void, Runtime1::throw_div0_exception(JavaThread* thread))
 674   NOT_PRODUCT(_throw_div0_exception_count++;)
 675   SharedRuntime::throw_and_post_jvmti_exception(thread, vmSymbols::java_lang_ArithmeticException(), "/ by zero");
 676 JRT_END
 677 
 678 
 679 JRT_ENTRY(void, Runtime1::throw_null_pointer_exception(JavaThread* thread))
 680   NOT_PRODUCT(_throw_null_pointer_exception_count++;)
 681   SharedRuntime::throw_and_post_jvmti_exception(thread, vmSymbols::java_lang_NullPointerException());
 682 JRT_END
 683 
 684 
 685 JRT_ENTRY(void, Runtime1::throw_class_cast_exception(JavaThread* thread, oopDesc* object))
 686   NOT_PRODUCT(_throw_class_cast_exception_count++;)
 687   ResourceMark rm(thread);
 688   char* message = SharedRuntime::generate_class_cast_message(
 689     thread, object->klass());
 690   SharedRuntime::throw_and_post_jvmti_exception(
 691     thread, vmSymbols::java_lang_ClassCastException(), message);
 692 JRT_END
 693 
 694 
 695 JRT_ENTRY(void, Runtime1::throw_incompatible_class_change_error(JavaThread* thread))
 696   NOT_PRODUCT(_throw_incompatible_class_change_error_count++;)
 697   ResourceMark rm(thread);
 698   SharedRuntime::throw_and_post_jvmti_exception(thread, vmSymbols::java_lang_IncompatibleClassChangeError());
 699 JRT_END
 700 
 701 
 702 JRT_ENTRY_NO_ASYNC(void, Runtime1::monitorenter(JavaThread* thread, oopDesc* obj, BasicObjectLock* lock))
 703   NOT_PRODUCT(_monitorenter_slowcase_cnt++;)
 704   if (PrintBiasedLockingStatistics) {
 705     Atomic::inc(BiasedLocking::slow_path_entry_count_addr());
 706   }
 707   Handle h_obj(thread, obj);
 708   assert(obj == lock->obj(), "must match");
 709   ObjectSynchronizer::enter(h_obj, lock->lock(), THREAD);
 710 JRT_END
 711 
 712 
 713 JRT_LEAF(void, Runtime1::monitorexit(JavaThread* thread, BasicObjectLock* lock))
 714   NOT_PRODUCT(_monitorexit_slowcase_cnt++;)
 715   assert(thread == JavaThread::current(), "threads must correspond");
 716   assert(thread->last_Java_sp(), "last_Java_sp must be set");
 717   // monitorexit is non-blocking (leaf routine) => no exceptions can be thrown
 718   EXCEPTION_MARK;
 719 
 720   oop obj = lock->obj();
 721   assert(oopDesc::is_oop(obj), "must be NULL or an object");
 722   ObjectSynchronizer::exit(obj, lock->lock(), THREAD);
 723 JRT_END
 724 
 725 // Cf. OptoRuntime::deoptimize_caller_frame
 726 JRT_ENTRY(void, Runtime1::deoptimize(JavaThread* thread, jint trap_request))
 727   // Called from within the owner thread, so no need for safepoint
 728   RegisterMap reg_map(thread, false);
 729   frame stub_frame = thread->last_frame();
 730   assert(stub_frame.is_runtime_frame(), "Sanity check");
 731   frame caller_frame = stub_frame.sender(&reg_map);
 732   nmethod* nm = caller_frame.cb()->as_nmethod_or_null();
 733   assert(nm != NULL, "Sanity check");
 734   methodHandle method(thread, nm->method());
 735   assert(nm == CodeCache::find_nmethod(caller_frame.pc()), "Should be the same");
 736   Deoptimization::DeoptAction action = Deoptimization::trap_request_action(trap_request);
 737   Deoptimization::DeoptReason reason = Deoptimization::trap_request_reason(trap_request);
 738 
 739   if (action == Deoptimization::Action_make_not_entrant) {
 740     if (nm->make_not_entrant()) {
 741       if (reason == Deoptimization::Reason_tenured) {
 742         MethodData* trap_mdo = Deoptimization::get_method_data(thread, method, true /*create_if_missing*/);
 743         if (trap_mdo != NULL) {
 744           trap_mdo->inc_tenure_traps();
 745         }
 746       }
 747     }
 748   }
 749 
 750   // Deoptimize the caller frame.
 751   Deoptimization::deoptimize_frame(thread, caller_frame.id());
 752   // Return to the now deoptimized frame.
 753 JRT_END
 754 
 755 
 756 #ifndef DEOPTIMIZE_WHEN_PATCHING
 757 
 758 static Klass* resolve_field_return_klass(const methodHandle& caller, int bci, TRAPS) {
 759   Bytecode_field field_access(caller, bci);
 760   // This can be static or non-static field access
 761   Bytecodes::Code code       = field_access.code();
 762 
 763   // We must load class, initialize class and resolve the field
 764   fieldDescriptor result; // initialize class if needed
 765   constantPoolHandle constants(THREAD, caller->constants());
 766   LinkResolver::resolve_field_access(result, constants, field_access.index(), caller, Bytecodes::java_code(code), CHECK_NULL);
 767   return result.field_holder();
 768 }
 769 
 770 
 771 //
 772 // This routine patches sites where a class wasn't loaded or
 773 // initialized at the time the code was generated.  It handles
 774 // references to classes, fields and forcing of initialization.  Most
 775 // of the cases are straightforward and involving simply forcing
 776 // resolution of a class, rewriting the instruction stream with the
 777 // needed constant and replacing the call in this function with the
 778 // patched code.  The case for static field is more complicated since
 779 // the thread which is in the process of initializing a class can
 780 // access it's static fields but other threads can't so the code
 781 // either has to deoptimize when this case is detected or execute a
 782 // check that the current thread is the initializing thread.  The
 783 // current
 784 //
 785 // Patches basically look like this:
 786 //
 787 //
 788 // patch_site: jmp patch stub     ;; will be patched
 789 // continue:   ...
 790 //             ...
 791 //             ...
 792 //             ...
 793 //
 794 // They have a stub which looks like this:
 795 //
 796 //             ;; patch body
 797 //             movl <const>, reg           (for class constants)
 798 //        <or> movl [reg1 + <const>], reg  (for field offsets)
 799 //        <or> movl reg, [reg1 + <const>]  (for field offsets)
 800 //             <being_init offset> <bytes to copy> <bytes to skip>
 801 // patch_stub: call Runtime1::patch_code (through a runtime stub)
 802 //             jmp patch_site
 803 //
 804 //
 805 // A normal patch is done by rewriting the patch body, usually a move,
 806 // and then copying it into place over top of the jmp instruction
 807 // being careful to flush caches and doing it in an MP-safe way.  The
 808 // constants following the patch body are used to find various pieces
 809 // of the patch relative to the call site for Runtime1::patch_code.
 810 // The case for getstatic and putstatic is more complicated because
 811 // getstatic and putstatic have special semantics when executing while
 812 // the class is being initialized.  getstatic/putstatic on a class
 813 // which is being_initialized may be executed by the initializing
 814 // thread but other threads have to block when they execute it.  This
 815 // is accomplished in compiled code by executing a test of the current
 816 // thread against the initializing thread of the class.  It's emitted
 817 // as boilerplate in their stub which allows the patched code to be
 818 // executed before it's copied back into the main body of the nmethod.
 819 //
 820 // being_init: get_thread(<tmp reg>
 821 //             cmpl [reg1 + <init_thread_offset>], <tmp reg>
 822 //             jne patch_stub
 823 //             movl [reg1 + <const>], reg  (for field offsets)  <or>
 824 //             movl reg, [reg1 + <const>]  (for field offsets)
 825 //             jmp continue
 826 //             <being_init offset> <bytes to copy> <bytes to skip>
 827 // patch_stub: jmp Runtim1::patch_code (through a runtime stub)
 828 //             jmp patch_site
 829 //
 830 // If the class is being initialized the patch body is rewritten and
 831 // the patch site is rewritten to jump to being_init, instead of
 832 // patch_stub.  Whenever this code is executed it checks the current
 833 // thread against the intializing thread so other threads will enter
 834 // the runtime and end up blocked waiting the class to finish
 835 // initializing inside the calls to resolve_field below.  The
 836 // initializing class will continue on it's way.  Once the class is
 837 // fully_initialized, the intializing_thread of the class becomes
 838 // NULL, so the next thread to execute this code will fail the test,
 839 // call into patch_code and complete the patching process by copying
 840 // the patch body back into the main part of the nmethod and resume
 841 // executing.
 842 
 843 // NB:
 844 //
 845 // Patchable instruction sequences inherently exhibit race conditions,
 846 // where thread A is patching an instruction at the same time thread B
 847 // is executing it.  The algorithms we use ensure that any observation
 848 // that B can make on any intermediate states during A's patching will
 849 // always end up with a correct outcome.  This is easiest if there are
 850 // few or no intermediate states.  (Some inline caches have two
 851 // related instructions that must be patched in tandem.  For those,
 852 // intermediate states seem to be unavoidable, but we will get the
 853 // right answer from all possible observation orders.)
 854 //
 855 // When patching the entry instruction at the head of a method, or a
 856 // linkable call instruction inside of a method, we try very hard to
 857 // use a patch sequence which executes as a single memory transaction.
 858 // This means, in practice, that when thread A patches an instruction,
 859 // it should patch a 32-bit or 64-bit word that somehow overlaps the
 860 // instruction or is contained in it.  We believe that memory hardware
 861 // will never break up such a word write, if it is naturally aligned
 862 // for the word being written.  We also know that some CPUs work very
 863 // hard to create atomic updates even of naturally unaligned words,
 864 // but we don't want to bet the farm on this always working.
 865 //
 866 // Therefore, if there is any chance of a race condition, we try to
 867 // patch only naturally aligned words, as single, full-word writes.
 868 
 869 JRT_ENTRY(void, Runtime1::patch_code(JavaThread* thread, Runtime1::StubID stub_id ))
 870   NOT_PRODUCT(_patch_code_slowcase_cnt++;)
 871 
 872   ResourceMark rm(thread);
 873   RegisterMap reg_map(thread, false);
 874   frame runtime_frame = thread->last_frame();
 875   frame caller_frame = runtime_frame.sender(&reg_map);
 876 
 877   // last java frame on stack
 878   vframeStream vfst(thread, true);
 879   assert(!vfst.at_end(), "Java frame must exist");
 880 
 881   methodHandle caller_method(THREAD, vfst.method());
 882   // Note that caller_method->code() may not be same as caller_code because of OSR's
 883   // Note also that in the presence of inlining it is not guaranteed
 884   // that caller_method() == caller_code->method()
 885 
 886   int bci = vfst.bci();
 887   Bytecodes::Code code = caller_method()->java_code_at(bci);
 888 
 889   // this is used by assertions in the access_field_patching_id
 890   BasicType patch_field_type = T_ILLEGAL;
 891   bool deoptimize_for_volatile = false;
 892   bool deoptimize_for_atomic = false;
 893   int patch_field_offset = -1;
 894   Klass* init_klass = NULL; // klass needed by load_klass_patching code
 895   Klass* load_klass = NULL; // klass needed by load_klass_patching code
 896   Handle mirror(THREAD, NULL);                    // oop needed by load_mirror_patching code
 897   Handle appendix(THREAD, NULL);                  // oop needed by appendix_patching code
 898   bool load_klass_or_mirror_patch_id =
 899     (stub_id == Runtime1::load_klass_patching_id || stub_id == Runtime1::load_mirror_patching_id);
 900 
 901   if (stub_id == Runtime1::access_field_patching_id) {
 902 
 903     Bytecode_field field_access(caller_method, bci);
 904     fieldDescriptor result; // initialize class if needed
 905     Bytecodes::Code code = field_access.code();
 906     constantPoolHandle constants(THREAD, caller_method->constants());
 907     LinkResolver::resolve_field_access(result, constants, field_access.index(), caller_method, Bytecodes::java_code(code), CHECK);
 908     patch_field_offset = result.offset();
 909 
 910     // If we're patching a field which is volatile then at compile it
 911     // must not have been know to be volatile, so the generated code
 912     // isn't correct for a volatile reference.  The nmethod has to be
 913     // deoptimized so that the code can be regenerated correctly.
 914     // This check is only needed for access_field_patching since this
 915     // is the path for patching field offsets.  load_klass is only
 916     // used for patching references to oops which don't need special
 917     // handling in the volatile case.
 918 
 919     deoptimize_for_volatile = result.access_flags().is_volatile();
 920 
 921     // If we are patching a field which should be atomic, then
 922     // the generated code is not correct either, force deoptimizing.
 923     // We need to only cover T_LONG and T_DOUBLE fields, as we can
 924     // break access atomicity only for them.
 925 
 926     // Strictly speaking, the deoptimization on 64-bit platforms
 927     // is unnecessary, and T_LONG stores on 32-bit platforms need
 928     // to be handled by special patching code when AlwaysAtomicAccesses
 929     // becomes product feature. At this point, we are still going
 930     // for the deoptimization for consistency against volatile
 931     // accesses.
 932 
 933     patch_field_type = result.field_type();
 934     deoptimize_for_atomic = (AlwaysAtomicAccesses && (patch_field_type == T_DOUBLE || patch_field_type == T_LONG));
 935 
 936   } else if (load_klass_or_mirror_patch_id) {
 937     Klass* k = NULL;
 938     switch (code) {
 939       case Bytecodes::_putstatic:
 940       case Bytecodes::_getstatic:
 941         { Klass* klass = resolve_field_return_klass(caller_method, bci, CHECK);
 942           init_klass = klass;
 943           mirror = Handle(THREAD, klass->java_mirror());
 944         }
 945         break;
 946       case Bytecodes::_new:
 947         { Bytecode_new bnew(caller_method(), caller_method->bcp_from(bci));
 948           k = caller_method->constants()->klass_at(bnew.index(), CHECK);
 949         }
 950         break;
 951       case Bytecodes::_multianewarray:
 952         { Bytecode_multianewarray mna(caller_method(), caller_method->bcp_from(bci));
 953           k = caller_method->constants()->klass_at(mna.index(), CHECK);
 954         }
 955         break;
 956       case Bytecodes::_instanceof:
 957         { Bytecode_instanceof io(caller_method(), caller_method->bcp_from(bci));
 958           k = caller_method->constants()->klass_at(io.index(), CHECK);
 959         }
 960         break;
 961       case Bytecodes::_checkcast:
 962         { Bytecode_checkcast cc(caller_method(), caller_method->bcp_from(bci));
 963           k = caller_method->constants()->klass_at(cc.index(), CHECK);
 964         }
 965         break;
 966       case Bytecodes::_anewarray:
 967         { Bytecode_anewarray anew(caller_method(), caller_method->bcp_from(bci));
 968           Klass* ek = caller_method->constants()->klass_at(anew.index(), CHECK);
 969           k = ek->array_klass(CHECK);
 970         }
 971         break;
 972       case Bytecodes::_ldc:
 973       case Bytecodes::_ldc_w:
 974         {
 975           Bytecode_loadconstant cc(caller_method, bci);
 976           oop m = cc.resolve_constant(CHECK);
 977           mirror = Handle(THREAD, m);
 978         }
 979         break;
 980       default: fatal("unexpected bytecode for load_klass_or_mirror_patch_id");
 981     }
 982     load_klass = k;
 983   } else if (stub_id == load_appendix_patching_id) {
 984     Bytecode_invoke bytecode(caller_method, bci);
 985     Bytecodes::Code bc = bytecode.invoke_code();
 986 
 987     CallInfo info;
 988     constantPoolHandle pool(thread, caller_method->constants());
 989     int index = bytecode.index();
 990     LinkResolver::resolve_invoke(info, Handle(), pool, index, bc, CHECK);
 991     switch (bc) {
 992       case Bytecodes::_invokehandle: {
 993         int cache_index = ConstantPool::decode_cpcache_index(index, true);
 994         assert(cache_index >= 0 && cache_index < pool->cache()->length(), "unexpected cache index");
 995         ConstantPoolCacheEntry* cpce = pool->cache()->entry_at(cache_index);
 996         cpce->set_method_handle(pool, info);
 997         appendix = Handle(THREAD, cpce->appendix_if_resolved(pool)); // just in case somebody already resolved the entry
 998         break;
 999       }
1000       case Bytecodes::_invokedynamic: {
1001         ConstantPoolCacheEntry* cpce = pool->invokedynamic_cp_cache_entry_at(index);
1002         cpce->set_dynamic_call(pool, info);
1003         appendix = Handle(THREAD, cpce->appendix_if_resolved(pool)); // just in case somebody already resolved the entry
1004         break;
1005       }
1006       default: fatal("unexpected bytecode for load_appendix_patching_id");
1007     }
1008   } else {
1009     ShouldNotReachHere();
1010   }
1011 
1012   if (deoptimize_for_volatile || deoptimize_for_atomic) {
1013     // At compile time we assumed the field wasn't volatile/atomic but after
1014     // loading it turns out it was volatile/atomic so we have to throw the
1015     // compiled code out and let it be regenerated.
1016     if (TracePatching) {
1017       if (deoptimize_for_volatile) {
1018         tty->print_cr("Deoptimizing for patching volatile field reference");
1019       }
1020       if (deoptimize_for_atomic) {
1021         tty->print_cr("Deoptimizing for patching atomic field reference");
1022       }
1023     }
1024 
1025     // It's possible the nmethod was invalidated in the last
1026     // safepoint, but if it's still alive then make it not_entrant.
1027     nmethod* nm = CodeCache::find_nmethod(caller_frame.pc());
1028     if (nm != NULL) {
1029       nm->make_not_entrant();
1030     }
1031 
1032     Deoptimization::deoptimize_frame(thread, caller_frame.id());
1033 
1034     // Return to the now deoptimized frame.
1035   }
1036 
1037   // Now copy code back
1038 
1039   {
1040     MutexLocker ml_patch (Patching_lock, Mutex::_no_safepoint_check_flag);
1041     //
1042     // Deoptimization may have happened while we waited for the lock.
1043     // In that case we don't bother to do any patching we just return
1044     // and let the deopt happen
1045     if (!caller_is_deopted()) {
1046       NativeGeneralJump* jump = nativeGeneralJump_at(caller_frame.pc());
1047       address instr_pc = jump->jump_destination();
1048       NativeInstruction* ni = nativeInstruction_at(instr_pc);
1049       if (ni->is_jump() ) {
1050         // the jump has not been patched yet
1051         // The jump destination is slow case and therefore not part of the stubs
1052         // (stubs are only for StaticCalls)
1053 
1054         // format of buffer
1055         //    ....
1056         //    instr byte 0     <-- copy_buff
1057         //    instr byte 1
1058         //    ..
1059         //    instr byte n-1
1060         //      n
1061         //    ....             <-- call destination
1062 
1063         address stub_location = caller_frame.pc() + PatchingStub::patch_info_offset();
1064         unsigned char* byte_count = (unsigned char*) (stub_location - 1);
1065         unsigned char* byte_skip = (unsigned char*) (stub_location - 2);
1066         unsigned char* being_initialized_entry_offset = (unsigned char*) (stub_location - 3);
1067         address copy_buff = stub_location - *byte_skip - *byte_count;
1068         address being_initialized_entry = stub_location - *being_initialized_entry_offset;
1069         if (TracePatching) {
1070           ttyLocker ttyl;
1071           tty->print_cr(" Patching %s at bci %d at address " INTPTR_FORMAT "  (%s)", Bytecodes::name(code), bci,
1072                         p2i(instr_pc), (stub_id == Runtime1::access_field_patching_id) ? "field" : "klass");
1073           nmethod* caller_code = CodeCache::find_nmethod(caller_frame.pc());
1074           assert(caller_code != NULL, "nmethod not found");
1075 
1076           // NOTE we use pc() not original_pc() because we already know they are
1077           // identical otherwise we'd have never entered this block of code
1078 
1079           const ImmutableOopMap* map = caller_code->oop_map_for_return_address(caller_frame.pc());
1080           assert(map != NULL, "null check");
1081           map->print();
1082           tty->cr();
1083 
1084           Disassembler::decode(copy_buff, copy_buff + *byte_count, tty);
1085         }
1086         // depending on the code below, do_patch says whether to copy the patch body back into the nmethod
1087         bool do_patch = true;
1088         if (stub_id == Runtime1::access_field_patching_id) {
1089           // The offset may not be correct if the class was not loaded at code generation time.
1090           // Set it now.
1091           NativeMovRegMem* n_move = nativeMovRegMem_at(copy_buff);
1092           assert(n_move->offset() == 0 || (n_move->offset() == 4 && (patch_field_type == T_DOUBLE || patch_field_type == T_LONG)), "illegal offset for type");
1093           assert(patch_field_offset >= 0, "illegal offset");
1094           n_move->add_offset_in_bytes(patch_field_offset);
1095         } else if (load_klass_or_mirror_patch_id) {
1096           // If a getstatic or putstatic is referencing a klass which
1097           // isn't fully initialized, the patch body isn't copied into
1098           // place until initialization is complete.  In this case the
1099           // patch site is setup so that any threads besides the
1100           // initializing thread are forced to come into the VM and
1101           // block.
1102           do_patch = (code != Bytecodes::_getstatic && code != Bytecodes::_putstatic) ||
1103                      InstanceKlass::cast(init_klass)->is_initialized();
1104           NativeGeneralJump* jump = nativeGeneralJump_at(instr_pc);
1105           if (jump->jump_destination() == being_initialized_entry) {
1106             assert(do_patch == true, "initialization must be complete at this point");
1107           } else {
1108             // patch the instruction <move reg, klass>
1109             NativeMovConstReg* n_copy = nativeMovConstReg_at(copy_buff);
1110 
1111             assert(n_copy->data() == 0 ||
1112                    n_copy->data() == (intptr_t)Universe::non_oop_word(),
1113                    "illegal init value");
1114             if (stub_id == Runtime1::load_klass_patching_id) {
1115               assert(load_klass != NULL, "klass not set");
1116               n_copy->set_data((intx) (load_klass));
1117             } else {
1118               assert(mirror() != NULL, "klass not set");
1119               // Don't need a G1 pre-barrier here since we assert above that data isn't an oop.
1120               n_copy->set_data(cast_from_oop<intx>(mirror()));
1121             }
1122 
1123             if (TracePatching) {
1124               Disassembler::decode(copy_buff, copy_buff + *byte_count, tty);
1125             }
1126           }
1127         } else if (stub_id == Runtime1::load_appendix_patching_id) {
1128           NativeMovConstReg* n_copy = nativeMovConstReg_at(copy_buff);
1129           assert(n_copy->data() == 0 ||
1130                  n_copy->data() == (intptr_t)Universe::non_oop_word(),
1131                  "illegal init value");
1132           n_copy->set_data(cast_from_oop<intx>(appendix()));
1133 
1134           if (TracePatching) {
1135             Disassembler::decode(copy_buff, copy_buff + *byte_count, tty);
1136           }
1137         } else {
1138           ShouldNotReachHere();
1139         }
1140 
1141 #if defined(SPARC) || defined(PPC32)
1142         if (load_klass_or_mirror_patch_id ||
1143             stub_id == Runtime1::load_appendix_patching_id) {
1144           // Update the location in the nmethod with the proper
1145           // metadata.  When the code was generated, a NULL was stuffed
1146           // in the metadata table and that table needs to be update to
1147           // have the right value.  On intel the value is kept
1148           // directly in the instruction instead of in the metadata
1149           // table, so set_data above effectively updated the value.
1150           nmethod* nm = CodeCache::find_nmethod(instr_pc);
1151           assert(nm != NULL, "invalid nmethod_pc");
1152           RelocIterator mds(nm, copy_buff, copy_buff + 1);
1153           bool found = false;
1154           while (mds.next() && !found) {
1155             if (mds.type() == relocInfo::oop_type) {
1156               assert(stub_id == Runtime1::load_mirror_patching_id ||
1157                      stub_id == Runtime1::load_appendix_patching_id, "wrong stub id");
1158               oop_Relocation* r = mds.oop_reloc();
1159               oop* oop_adr = r->oop_addr();
1160               *oop_adr = stub_id == Runtime1::load_mirror_patching_id ? mirror() : appendix();
1161               r->fix_oop_relocation();
1162               found = true;
1163             } else if (mds.type() == relocInfo::metadata_type) {
1164               assert(stub_id == Runtime1::load_klass_patching_id, "wrong stub id");
1165               metadata_Relocation* r = mds.metadata_reloc();
1166               Metadata** metadata_adr = r->metadata_addr();
1167               *metadata_adr = load_klass;
1168               r->fix_metadata_relocation();
1169               found = true;
1170             }
1171           }
1172           assert(found, "the metadata must exist!");
1173         }
1174 #endif
1175         if (do_patch) {
1176           // replace instructions
1177           // first replace the tail, then the call
1178 #ifdef ARM
1179           if((load_klass_or_mirror_patch_id ||
1180               stub_id == Runtime1::load_appendix_patching_id) &&
1181               nativeMovConstReg_at(copy_buff)->is_pc_relative()) {
1182             nmethod* nm = CodeCache::find_nmethod(instr_pc);
1183             address addr = NULL;
1184             assert(nm != NULL, "invalid nmethod_pc");
1185             RelocIterator mds(nm, copy_buff, copy_buff + 1);
1186             while (mds.next()) {
1187               if (mds.type() == relocInfo::oop_type) {
1188                 assert(stub_id == Runtime1::load_mirror_patching_id ||
1189                        stub_id == Runtime1::load_appendix_patching_id, "wrong stub id");
1190                 oop_Relocation* r = mds.oop_reloc();
1191                 addr = (address)r->oop_addr();
1192                 break;
1193               } else if (mds.type() == relocInfo::metadata_type) {
1194                 assert(stub_id == Runtime1::load_klass_patching_id, "wrong stub id");
1195                 metadata_Relocation* r = mds.metadata_reloc();
1196                 addr = (address)r->metadata_addr();
1197                 break;
1198               }
1199             }
1200             assert(addr != NULL, "metadata relocation must exist");
1201             copy_buff -= *byte_count;
1202             NativeMovConstReg* n_copy2 = nativeMovConstReg_at(copy_buff);
1203             n_copy2->set_pc_relative_offset(addr, instr_pc);
1204           }
1205 #endif
1206 
1207           for (int i = NativeGeneralJump::instruction_size; i < *byte_count; i++) {
1208             address ptr = copy_buff + i;
1209             int a_byte = (*ptr) & 0xFF;
1210             address dst = instr_pc + i;
1211             *(unsigned char*)dst = (unsigned char) a_byte;
1212           }
1213           ICache::invalidate_range(instr_pc, *byte_count);
1214           NativeGeneralJump::replace_mt_safe(instr_pc, copy_buff);
1215 
1216           if (load_klass_or_mirror_patch_id ||
1217               stub_id == Runtime1::load_appendix_patching_id) {
1218             relocInfo::relocType rtype =
1219               (stub_id == Runtime1::load_klass_patching_id) ?
1220                                    relocInfo::metadata_type :
1221                                    relocInfo::oop_type;
1222             // update relocInfo to metadata
1223             nmethod* nm = CodeCache::find_nmethod(instr_pc);
1224             assert(nm != NULL, "invalid nmethod_pc");
1225 
1226             // The old patch site is now a move instruction so update
1227             // the reloc info so that it will get updated during
1228             // future GCs.
1229             RelocIterator iter(nm, (address)instr_pc, (address)(instr_pc + 1));
1230             relocInfo::change_reloc_info_for_address(&iter, (address) instr_pc,
1231                                                      relocInfo::none, rtype);
1232 #ifdef SPARC
1233             // Sparc takes two relocations for an metadata so update the second one.
1234             address instr_pc2 = instr_pc + NativeMovConstReg::add_offset;
1235             RelocIterator iter2(nm, instr_pc2, instr_pc2 + 1);
1236             relocInfo::change_reloc_info_for_address(&iter2, (address) instr_pc2,
1237                                                      relocInfo::none, rtype);
1238 #endif
1239 #ifdef PPC32
1240           { address instr_pc2 = instr_pc + NativeMovConstReg::lo_offset;
1241             RelocIterator iter2(nm, instr_pc2, instr_pc2 + 1);
1242             relocInfo::change_reloc_info_for_address(&iter2, (address) instr_pc2,
1243                                                      relocInfo::none, rtype);
1244           }
1245 #endif
1246           }
1247 
1248         } else {
1249           ICache::invalidate_range(copy_buff, *byte_count);
1250           NativeGeneralJump::insert_unconditional(instr_pc, being_initialized_entry);
1251         }
1252       }
1253     }
1254   }
1255 
1256   // If we are patching in a non-perm oop, make sure the nmethod
1257   // is on the right list.
1258   {
1259     MutexLocker ml_code (CodeCache_lock, Mutex::_no_safepoint_check_flag);
1260     nmethod* nm = CodeCache::find_nmethod(caller_frame.pc());
1261     guarantee(nm != NULL, "only nmethods can contain non-perm oops");
1262 
1263     // Since we've patched some oops in the nmethod,
1264     // (re)register it with the heap.
1265     Universe::heap()->register_nmethod(nm);
1266   }
1267 JRT_END
1268 
1269 #else // DEOPTIMIZE_WHEN_PATCHING
1270 
1271 JRT_ENTRY(void, Runtime1::patch_code(JavaThread* thread, Runtime1::StubID stub_id ))
1272   RegisterMap reg_map(thread, false);
1273 
1274   NOT_PRODUCT(_patch_code_slowcase_cnt++;)
1275   if (TracePatching) {
1276     tty->print_cr("Deoptimizing because patch is needed");
1277   }
1278 
1279   frame runtime_frame = thread->last_frame();
1280   frame caller_frame = runtime_frame.sender(&reg_map);
1281 
1282   // It's possible the nmethod was invalidated in the last
1283   // safepoint, but if it's still alive then make it not_entrant.
1284   nmethod* nm = CodeCache::find_nmethod(caller_frame.pc());
1285   if (nm != NULL) {
1286     nm->make_not_entrant();
1287   }
1288 
1289   Deoptimization::deoptimize_frame(thread, caller_frame.id());
1290 
1291   // Return to the now deoptimized frame.
1292 JRT_END
1293 
1294 #endif // DEOPTIMIZE_WHEN_PATCHING
1295 
1296 //
1297 // Entry point for compiled code. We want to patch a nmethod.
1298 // We don't do a normal VM transition here because we want to
1299 // know after the patching is complete and any safepoint(s) are taken
1300 // if the calling nmethod was deoptimized. We do this by calling a
1301 // helper method which does the normal VM transition and when it
1302 // completes we can check for deoptimization. This simplifies the
1303 // assembly code in the cpu directories.
1304 //
1305 int Runtime1::move_klass_patching(JavaThread* thread) {
1306 //
1307 // NOTE: we are still in Java
1308 //
1309   Thread* THREAD = thread;
1310   debug_only(NoHandleMark nhm;)
1311   {
1312     // Enter VM mode
1313 
1314     ResetNoHandleMark rnhm;
1315     patch_code(thread, load_klass_patching_id);
1316   }
1317   // Back in JAVA, use no oops DON'T safepoint
1318 
1319   // Return true if calling code is deoptimized
1320 
1321   return caller_is_deopted();
1322 }
1323 
1324 int Runtime1::move_mirror_patching(JavaThread* thread) {
1325 //
1326 // NOTE: we are still in Java
1327 //
1328   Thread* THREAD = thread;
1329   debug_only(NoHandleMark nhm;)
1330   {
1331     // Enter VM mode
1332 
1333     ResetNoHandleMark rnhm;
1334     patch_code(thread, load_mirror_patching_id);
1335   }
1336   // Back in JAVA, use no oops DON'T safepoint
1337 
1338   // Return true if calling code is deoptimized
1339 
1340   return caller_is_deopted();
1341 }
1342 
1343 int Runtime1::move_appendix_patching(JavaThread* thread) {
1344 //
1345 // NOTE: we are still in Java
1346 //
1347   Thread* THREAD = thread;
1348   debug_only(NoHandleMark nhm;)
1349   {
1350     // Enter VM mode
1351 
1352     ResetNoHandleMark rnhm;
1353     patch_code(thread, load_appendix_patching_id);
1354   }
1355   // Back in JAVA, use no oops DON'T safepoint
1356 
1357   // Return true if calling code is deoptimized
1358 
1359   return caller_is_deopted();
1360 }
1361 //
1362 // Entry point for compiled code. We want to patch a nmethod.
1363 // We don't do a normal VM transition here because we want to
1364 // know after the patching is complete and any safepoint(s) are taken
1365 // if the calling nmethod was deoptimized. We do this by calling a
1366 // helper method which does the normal VM transition and when it
1367 // completes we can check for deoptimization. This simplifies the
1368 // assembly code in the cpu directories.
1369 //
1370 
1371 int Runtime1::access_field_patching(JavaThread* thread) {
1372 //
1373 // NOTE: we are still in Java
1374 //
1375   Thread* THREAD = thread;
1376   debug_only(NoHandleMark nhm;)
1377   {
1378     // Enter VM mode
1379 
1380     ResetNoHandleMark rnhm;
1381     patch_code(thread, access_field_patching_id);
1382   }
1383   // Back in JAVA, use no oops DON'T safepoint
1384 
1385   // Return true if calling code is deoptimized
1386 
1387   return caller_is_deopted();
1388 JRT_END
1389 
1390 
1391 JRT_LEAF(void, Runtime1::trace_block_entry(jint block_id))
1392   // for now we just print out the block id
1393   tty->print("%d ", block_id);
1394 JRT_END
1395 
1396 
1397 JRT_LEAF(int, Runtime1::is_instance_of(oopDesc* mirror, oopDesc* obj))
1398   // had to return int instead of bool, otherwise there may be a mismatch
1399   // between the C calling convention and the Java one.
1400   // e.g., on x86, GCC may clear only %al when returning a bool false, but
1401   // JVM takes the whole %eax as the return value, which may misinterpret
1402   // the return value as a boolean true.
1403 
1404   assert(mirror != NULL, "should null-check on mirror before calling");
1405   Klass* k = java_lang_Class::as_Klass(mirror);
1406   return (k != NULL && obj != NULL && obj->is_a(k)) ? 1 : 0;
1407 JRT_END
1408 
1409 JRT_ENTRY(void, Runtime1::predicate_failed_trap(JavaThread* thread))
1410   ResourceMark rm;
1411 
1412   assert(!TieredCompilation, "incompatible with tiered compilation");
1413 
1414   RegisterMap reg_map(thread, false);
1415   frame runtime_frame = thread->last_frame();
1416   frame caller_frame = runtime_frame.sender(&reg_map);
1417 
1418   nmethod* nm = CodeCache::find_nmethod(caller_frame.pc());
1419   assert (nm != NULL, "no more nmethod?");
1420   nm->make_not_entrant();
1421 
1422   methodHandle m(nm->method());
1423   MethodData* mdo = m->method_data();
1424 
1425   if (mdo == NULL && !HAS_PENDING_EXCEPTION) {
1426     // Build an MDO.  Ignore errors like OutOfMemory;
1427     // that simply means we won't have an MDO to update.
1428     Method::build_interpreter_method_data(m, THREAD);
1429     if (HAS_PENDING_EXCEPTION) {
1430       assert((PENDING_EXCEPTION->is_a(SystemDictionary::OutOfMemoryError_klass())), "we expect only an OOM error here");
1431       CLEAR_PENDING_EXCEPTION;
1432     }
1433     mdo = m->method_data();
1434   }
1435 
1436   if (mdo != NULL) {
1437     mdo->inc_trap_count(Deoptimization::Reason_none);
1438   }
1439 
1440   if (TracePredicateFailedTraps) {
1441     stringStream ss1, ss2;
1442     vframeStream vfst(thread);
1443     methodHandle inlinee = methodHandle(vfst.method());
1444     inlinee->print_short_name(&ss1);
1445     m->print_short_name(&ss2);
1446     tty->print_cr("Predicate failed trap in method %s at bci %d inlined in %s at pc " INTPTR_FORMAT, ss1.as_string(), vfst.bci(), ss2.as_string(), p2i(caller_frame.pc()));
1447   }
1448 
1449 
1450   Deoptimization::deoptimize_frame(thread, caller_frame.id());
1451 
1452 JRT_END
1453 
1454 #ifndef PRODUCT
1455 void Runtime1::print_statistics() {
1456   tty->print_cr("C1 Runtime statistics:");
1457   tty->print_cr(" _resolve_invoke_virtual_cnt:     %d", SharedRuntime::_resolve_virtual_ctr);
1458   tty->print_cr(" _resolve_invoke_opt_virtual_cnt: %d", SharedRuntime::_resolve_opt_virtual_ctr);
1459   tty->print_cr(" _resolve_invoke_static_cnt:      %d", SharedRuntime::_resolve_static_ctr);
1460   tty->print_cr(" _handle_wrong_method_cnt:        %d", SharedRuntime::_wrong_method_ctr);
1461   tty->print_cr(" _ic_miss_cnt:                    %d", SharedRuntime::_ic_miss_ctr);
1462   tty->print_cr(" _generic_arraycopy_cnt:          %d", _generic_arraycopy_cnt);
1463   tty->print_cr(" _generic_arraycopystub_cnt:      %d", _generic_arraycopystub_cnt);
1464   tty->print_cr(" _byte_arraycopy_cnt:             %d", _byte_arraycopy_stub_cnt);
1465   tty->print_cr(" _short_arraycopy_cnt:            %d", _short_arraycopy_stub_cnt);
1466   tty->print_cr(" _int_arraycopy_cnt:              %d", _int_arraycopy_stub_cnt);
1467   tty->print_cr(" _long_arraycopy_cnt:             %d", _long_arraycopy_stub_cnt);
1468   tty->print_cr(" _oop_arraycopy_cnt:              %d", _oop_arraycopy_stub_cnt);
1469   tty->print_cr(" _arraycopy_slowcase_cnt:         %d", _arraycopy_slowcase_cnt);
1470   tty->print_cr(" _arraycopy_checkcast_cnt:        %d", _arraycopy_checkcast_cnt);
1471   tty->print_cr(" _arraycopy_checkcast_attempt_cnt:%d", _arraycopy_checkcast_attempt_cnt);
1472 
1473   tty->print_cr(" _new_type_array_slowcase_cnt:    %d", _new_type_array_slowcase_cnt);
1474   tty->print_cr(" _new_object_array_slowcase_cnt:  %d", _new_object_array_slowcase_cnt);
1475   tty->print_cr(" _new_instance_slowcase_cnt:      %d", _new_instance_slowcase_cnt);
1476   tty->print_cr(" _new_multi_array_slowcase_cnt:   %d", _new_multi_array_slowcase_cnt);
1477   tty->print_cr(" _monitorenter_slowcase_cnt:      %d", _monitorenter_slowcase_cnt);
1478   tty->print_cr(" _monitorexit_slowcase_cnt:       %d", _monitorexit_slowcase_cnt);
1479   tty->print_cr(" _patch_code_slowcase_cnt:        %d", _patch_code_slowcase_cnt);
1480 
1481   tty->print_cr(" _throw_range_check_exception_count:            %d:", _throw_range_check_exception_count);
1482   tty->print_cr(" _throw_index_exception_count:                  %d:", _throw_index_exception_count);
1483   tty->print_cr(" _throw_div0_exception_count:                   %d:", _throw_div0_exception_count);
1484   tty->print_cr(" _throw_null_pointer_exception_count:           %d:", _throw_null_pointer_exception_count);
1485   tty->print_cr(" _throw_class_cast_exception_count:             %d:", _throw_class_cast_exception_count);
1486   tty->print_cr(" _throw_incompatible_class_change_error_count:  %d:", _throw_incompatible_class_change_error_count);
1487   tty->print_cr(" _throw_array_store_exception_count:            %d:", _throw_array_store_exception_count);
1488   tty->print_cr(" _throw_count:                                  %d:", _throw_count);
1489 
1490   SharedRuntime::print_ic_miss_histogram();
1491   tty->cr();
1492 }
1493 #endif // PRODUCT