1 /*
   2  * Copyright (c) 1999, 2018, 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 "oops/access.inline.hpp"
  52 #include "oops/objArrayOop.inline.hpp"
  53 #include "oops/objArrayKlass.hpp"
  54 #include "oops/oop.inline.hpp"
  55 #include "runtime/atomic.hpp"
  56 #include "runtime/biasedLocking.hpp"
  57 #include "runtime/compilationPolicy.hpp"
  58 #include "runtime/fieldDescriptor.inline.hpp"
  59 #include "runtime/frame.inline.hpp"
  60 #include "runtime/interfaceSupport.inline.hpp"
  61 #include "runtime/javaCalls.hpp"
  62 #include "runtime/sharedRuntime.hpp"
  63 #include "runtime/threadCritical.hpp"
  64 #include "runtime/vframe.inline.hpp"
  65 #include "runtime/vframeArray.hpp"
  66 #include "runtime/vm_version.hpp"
  67 #include "utilities/copy.hpp"
  68 #include "utilities/events.hpp"
  69 
  70 
  71 // Implementation of StubAssembler
  72 
  73 StubAssembler::StubAssembler(CodeBuffer* code, const char * name, int stub_id) : C1_MacroAssembler(code) {
  74   _name = name;
  75   _must_gc_arguments = false;
  76   _frame_size = no_frame_size;
  77   _num_rt_args = 0;
  78   _stub_id = stub_id;
  79 }
  80 
  81 
  82 void StubAssembler::set_info(const char* name, bool must_gc_arguments) {
  83   _name = name;
  84   _must_gc_arguments = must_gc_arguments;
  85 }
  86 
  87 
  88 void StubAssembler::set_frame_size(int size) {
  89   if (_frame_size == no_frame_size) {
  90     _frame_size = size;
  91   }
  92   assert(_frame_size == size, "can't change the frame size");
  93 }
  94 
  95 
  96 void StubAssembler::set_num_rt_args(int args) {
  97   if (_num_rt_args == 0) {
  98     _num_rt_args = args;
  99   }
 100   assert(_num_rt_args == args, "can't change the number of args");
 101 }
 102 
 103 // Implementation of Runtime1
 104 
 105 CodeBlob* Runtime1::_blobs[Runtime1::number_of_ids];
 106 const char *Runtime1::_blob_names[] = {
 107   RUNTIME1_STUBS(STUB_NAME, LAST_STUB_NAME)
 108 };
 109 
 110 #ifndef PRODUCT
 111 // statistics
 112 int Runtime1::_generic_arraycopy_cnt = 0;
 113 int Runtime1::_generic_arraycopystub_cnt = 0;
 114 int Runtime1::_arraycopy_slowcase_cnt = 0;
 115 int Runtime1::_arraycopy_checkcast_cnt = 0;
 116 int Runtime1::_arraycopy_checkcast_attempt_cnt = 0;
 117 int Runtime1::_new_type_array_slowcase_cnt = 0;
 118 int Runtime1::_new_object_array_slowcase_cnt = 0;
 119 int Runtime1::_new_instance_slowcase_cnt = 0;
 120 int Runtime1::_new_multi_array_slowcase_cnt = 0;
 121 int Runtime1::_monitorenter_slowcase_cnt = 0;
 122 int Runtime1::_monitorexit_slowcase_cnt = 0;
 123 int Runtime1::_patch_code_slowcase_cnt = 0;
 124 int Runtime1::_throw_range_check_exception_count = 0;
 125 int Runtime1::_throw_index_exception_count = 0;
 126 int Runtime1::_throw_div0_exception_count = 0;
 127 int Runtime1::_throw_null_pointer_exception_count = 0;
 128 int Runtime1::_throw_class_cast_exception_count = 0;
 129 int Runtime1::_throw_incompatible_class_change_error_count = 0;
 130 int Runtime1::_throw_array_store_exception_count = 0;
 131 int Runtime1::_throw_count = 0;
 132 
 133 static int _byte_arraycopy_stub_cnt = 0;
 134 static int _short_arraycopy_stub_cnt = 0;
 135 static int _int_arraycopy_stub_cnt = 0;
 136 static int _long_arraycopy_stub_cnt = 0;
 137 static int _oop_arraycopy_stub_cnt = 0;
 138 
 139 address Runtime1::arraycopy_count_address(BasicType type) {
 140   switch (type) {
 141   case T_BOOLEAN:
 142   case T_BYTE:   return (address)&_byte_arraycopy_stub_cnt;
 143   case T_CHAR:
 144   case T_SHORT:  return (address)&_short_arraycopy_stub_cnt;
 145   case T_FLOAT:
 146   case T_INT:    return (address)&_int_arraycopy_stub_cnt;
 147   case T_DOUBLE:
 148   case T_LONG:   return (address)&_long_arraycopy_stub_cnt;
 149   case T_ARRAY:
 150   case T_OBJECT: return (address)&_oop_arraycopy_stub_cnt;
 151   default:
 152     ShouldNotReachHere();
 153     return NULL;
 154   }
 155 }
 156 
 157 
 158 #endif
 159 
 160 // Simple helper to see if the caller of a runtime stub which
 161 // entered the VM has been deoptimized
 162 
 163 static bool caller_is_deopted() {
 164   JavaThread* thread = JavaThread::current();
 165   RegisterMap reg_map(thread, false);
 166   frame runtime_frame = thread->last_frame();
 167   frame caller_frame = runtime_frame.sender(&reg_map);
 168   assert(caller_frame.is_compiled_frame(), "must be compiled");
 169   return caller_frame.is_deoptimized_frame();
 170 }
 171 
 172 // Stress deoptimization
 173 static void deopt_caller() {
 174   if ( !caller_is_deopted()) {
 175     JavaThread* thread = JavaThread::current();
 176     RegisterMap reg_map(thread, false);
 177     frame runtime_frame = thread->last_frame();
 178     frame caller_frame = runtime_frame.sender(&reg_map);
 179     Deoptimization::deoptimize_frame(thread, caller_frame.id());
 180     assert(caller_is_deopted(), "Must be deoptimized");
 181   }
 182 }
 183 
 184 class StubIDStubAssemblerCodeGenClosure: public StubAssemblerCodeGenClosure {
 185  private:
 186   Runtime1::StubID _id;
 187  public:
 188   StubIDStubAssemblerCodeGenClosure(Runtime1::StubID id) : _id(id) {}
 189   virtual OopMapSet* generate_code(StubAssembler* sasm) {
 190     return Runtime1::generate_code_for(_id, sasm);
 191   }
 192 };
 193 
 194 CodeBlob* Runtime1::generate_blob(BufferBlob* buffer_blob, int stub_id, const char* name, bool expect_oop_map, StubAssemblerCodeGenClosure* cl) {
 195   ResourceMark rm;
 196   // create code buffer for code storage
 197   CodeBuffer code(buffer_blob);
 198 
 199   OopMapSet* oop_maps;
 200   int frame_size;
 201   bool must_gc_arguments;
 202 
 203   Compilation::setup_code_buffer(&code, 0);
 204 
 205   // create assembler for code generation
 206   StubAssembler* sasm = new StubAssembler(&code, name, stub_id);
 207   // generate code for runtime stub
 208   oop_maps = cl->generate_code(sasm);
 209   assert(oop_maps == NULL || sasm->frame_size() != no_frame_size,
 210          "if stub has an oop map it must have a valid frame size");
 211   assert(!expect_oop_map || oop_maps != NULL, "must have an oopmap");
 212 
 213   // align so printing shows nop's instead of random code at the end (SimpleStubs are aligned)
 214   sasm->align(BytesPerWord);
 215   // make sure all code is in code buffer
 216   sasm->flush();
 217 
 218   frame_size = sasm->frame_size();
 219   must_gc_arguments = sasm->must_gc_arguments();
 220   // create blob - distinguish a few special cases
 221   CodeBlob* blob = RuntimeStub::new_runtime_stub(name,
 222                                                  &code,
 223                                                  CodeOffsets::frame_never_safe,
 224                                                  frame_size,
 225                                                  oop_maps,
 226                                                  must_gc_arguments);
 227   assert(blob != NULL, "blob must exist");
 228   return blob;
 229 }
 230 
 231 void Runtime1::generate_blob_for(BufferBlob* buffer_blob, StubID id) {
 232   assert(0 <= id && id < number_of_ids, "illegal stub id");
 233   bool expect_oop_map = true;
 234 #ifdef ASSERT
 235   // Make sure that stubs that need oopmaps have them
 236   switch (id) {
 237     // These stubs don't need to have an oopmap
 238   case dtrace_object_alloc_id:
 239   case slow_subtype_check_id:
 240   case fpu2long_stub_id:
 241   case unwind_exception_id:
 242   case counter_overflow_id:
 243 #if defined(SPARC) || defined(PPC32)
 244   case handle_exception_nofpu_id:  // Unused on sparc
 245 #endif
 246     expect_oop_map = false;
 247     break;
 248   default:
 249     break;
 250   }
 251 #endif
 252   StubIDStubAssemblerCodeGenClosure cl(id);
 253   CodeBlob* blob = generate_blob(buffer_blob, id, name_for(id), expect_oop_map, &cl);
 254   // install blob
 255   _blobs[id] = blob;
 256 }
 257 
 258 void Runtime1::initialize(BufferBlob* blob) {
 259   // platform-dependent initialization
 260   initialize_pd();
 261   // generate stubs
 262   for (int id = 0; id < number_of_ids; id++) generate_blob_for(blob, (StubID)id);
 263   // printing
 264 #ifndef PRODUCT
 265   if (PrintSimpleStubs) {
 266     ResourceMark rm;
 267     for (int id = 0; id < number_of_ids; id++) {
 268       _blobs[id]->print();
 269       if (_blobs[id]->oop_maps() != NULL) {
 270         _blobs[id]->oop_maps()->print();
 271       }
 272     }
 273   }
 274 #endif
 275   BarrierSetC1* bs = BarrierSet::barrier_set()->barrier_set_c1();
 276   bs->generate_c1_runtime_stubs(blob);
 277 }
 278 
 279 CodeBlob* Runtime1::blob_for(StubID id) {
 280   assert(0 <= id && id < number_of_ids, "illegal stub id");
 281   return _blobs[id];
 282 }
 283 
 284 
 285 const char* Runtime1::name_for(StubID id) {
 286   assert(0 <= id && id < number_of_ids, "illegal stub id");
 287   return _blob_names[id];
 288 }
 289 
 290 const char* Runtime1::name_for_address(address entry) {
 291   for (int id = 0; id < number_of_ids; id++) {
 292     if (entry == entry_for((StubID)id)) return name_for((StubID)id);
 293   }
 294 
 295 #define FUNCTION_CASE(a, f) \
 296   if ((intptr_t)a == CAST_FROM_FN_PTR(intptr_t, f))  return #f
 297 
 298   FUNCTION_CASE(entry, os::javaTimeMillis);
 299   FUNCTION_CASE(entry, os::javaTimeNanos);
 300   FUNCTION_CASE(entry, SharedRuntime::OSR_migration_end);
 301   FUNCTION_CASE(entry, SharedRuntime::d2f);
 302   FUNCTION_CASE(entry, SharedRuntime::d2i);
 303   FUNCTION_CASE(entry, SharedRuntime::d2l);
 304   FUNCTION_CASE(entry, SharedRuntime::dcos);
 305   FUNCTION_CASE(entry, SharedRuntime::dexp);
 306   FUNCTION_CASE(entry, SharedRuntime::dlog);
 307   FUNCTION_CASE(entry, SharedRuntime::dlog10);
 308   FUNCTION_CASE(entry, SharedRuntime::dpow);
 309   FUNCTION_CASE(entry, SharedRuntime::drem);
 310   FUNCTION_CASE(entry, SharedRuntime::dsin);
 311   FUNCTION_CASE(entry, SharedRuntime::dtan);
 312   FUNCTION_CASE(entry, SharedRuntime::f2i);
 313   FUNCTION_CASE(entry, SharedRuntime::f2l);
 314   FUNCTION_CASE(entry, SharedRuntime::frem);
 315   FUNCTION_CASE(entry, SharedRuntime::l2d);
 316   FUNCTION_CASE(entry, SharedRuntime::l2f);
 317   FUNCTION_CASE(entry, SharedRuntime::ldiv);
 318   FUNCTION_CASE(entry, SharedRuntime::lmul);
 319   FUNCTION_CASE(entry, SharedRuntime::lrem);
 320   FUNCTION_CASE(entry, SharedRuntime::lrem);
 321   FUNCTION_CASE(entry, SharedRuntime::dtrace_method_entry);
 322   FUNCTION_CASE(entry, SharedRuntime::dtrace_method_exit);
 323   FUNCTION_CASE(entry, is_instance_of);
 324   FUNCTION_CASE(entry, trace_block_entry);
 325 #ifdef JFR_HAVE_INTRINSICS
 326   FUNCTION_CASE(entry, JFR_TIME_FUNCTION);
 327 #endif
 328   FUNCTION_CASE(entry, StubRoutines::updateBytesCRC32());
 329   FUNCTION_CASE(entry, StubRoutines::updateBytesCRC32C());
 330   FUNCTION_CASE(entry, StubRoutines::vectorizedMismatch());
 331   FUNCTION_CASE(entry, StubRoutines::dexp());
 332   FUNCTION_CASE(entry, StubRoutines::dlog());
 333   FUNCTION_CASE(entry, StubRoutines::dlog10());
 334   FUNCTION_CASE(entry, StubRoutines::dpow());
 335   FUNCTION_CASE(entry, StubRoutines::dsin());
 336   FUNCTION_CASE(entry, StubRoutines::dcos());
 337   FUNCTION_CASE(entry, StubRoutines::dtan());
 338 
 339 #undef FUNCTION_CASE
 340 
 341   // Soft float adds more runtime names.
 342   return pd_name_for_address(entry);
 343 }
 344 
 345 
 346 JRT_ENTRY(void, Runtime1::new_instance(JavaThread* thread, Klass* klass))
 347   NOT_PRODUCT(_new_instance_slowcase_cnt++;)
 348 
 349   assert(klass->is_klass(), "not a class");
 350   Handle holder(THREAD, klass->klass_holder()); // keep the klass alive
 351   InstanceKlass* h = InstanceKlass::cast(klass);
 352   h->check_valid_for_instantiation(true, CHECK);
 353   // make sure klass is initialized
 354   h->initialize(CHECK);
 355   // allocate instance and return via TLS
 356   oop obj = h->allocate_instance(CHECK);
 357   thread->set_vm_result(obj);
 358 JRT_END
 359 
 360 
 361 JRT_ENTRY(void, Runtime1::new_type_array(JavaThread* thread, Klass* klass, jint length))
 362   NOT_PRODUCT(_new_type_array_slowcase_cnt++;)
 363   // Note: no handle for klass needed since they are not used
 364   //       anymore after new_typeArray() and no GC can happen before.
 365   //       (This may have to change if this code changes!)
 366   assert(klass->is_klass(), "not a class");
 367   BasicType elt_type = TypeArrayKlass::cast(klass)->element_type();
 368   oop obj = oopFactory::new_typeArray(elt_type, length, CHECK);
 369   thread->set_vm_result(obj);
 370   // This is pretty rare but this runtime patch is stressful to deoptimization
 371   // if we deoptimize here so force a deopt to stress the path.
 372   if (DeoptimizeALot) {
 373     deopt_caller();
 374   }
 375 
 376 JRT_END
 377 
 378 
 379 JRT_ENTRY(void, Runtime1::new_object_array(JavaThread* thread, Klass* array_klass, jint length))
 380   NOT_PRODUCT(_new_object_array_slowcase_cnt++;)
 381 
 382   // Note: no handle for klass needed since they are not used
 383   //       anymore after new_objArray() and no GC can happen before.
 384   //       (This may have to change if this code changes!)
 385   assert(array_klass->is_klass(), "not a class");
 386   Handle holder(THREAD, array_klass->klass_holder()); // keep the klass alive
 387   Klass* elem_klass = ObjArrayKlass::cast(array_klass)->element_klass();
 388   objArrayOop obj = oopFactory::new_objArray(elem_klass, length, CHECK);
 389   thread->set_vm_result(obj);
 390   // This is pretty rare but this runtime patch is stressful to deoptimization
 391   // if we deoptimize here so force a deopt to stress the path.
 392   if (DeoptimizeALot) {
 393     deopt_caller();
 394   }
 395 JRT_END
 396 
 397 
 398 JRT_ENTRY(void, Runtime1::new_multi_array(JavaThread* thread, Klass* klass, int rank, jint* dims))
 399   NOT_PRODUCT(_new_multi_array_slowcase_cnt++;)
 400 
 401   assert(klass->is_klass(), "not a class");
 402   assert(rank >= 1, "rank must be nonzero");
 403   Handle holder(THREAD, klass->klass_holder()); // keep the klass alive
 404   oop obj = ArrayKlass::cast(klass)->multi_allocate(rank, dims, CHECK);
 405   thread->set_vm_result(obj);
 406 JRT_END
 407 
 408 
 409 JRT_ENTRY(void, Runtime1::unimplemented_entry(JavaThread* thread, StubID id))
 410   tty->print_cr("Runtime1::entry_for(%d) returned unimplemented entry point", id);
 411 JRT_END
 412 
 413 
 414 JRT_ENTRY(void, Runtime1::throw_array_store_exception(JavaThread* thread, oopDesc* obj))
 415   ResourceMark rm(thread);
 416   const char* klass_name = obj->klass()->external_name();
 417   SharedRuntime::throw_and_post_jvmti_exception(thread, vmSymbols::java_lang_ArrayStoreException(), klass_name);
 418 JRT_END
 419 
 420 
 421 // counter_overflow() is called from within C1-compiled methods. The enclosing method is the method
 422 // associated with the top activation record. The inlinee (that is possibly included in the enclosing
 423 // method) method oop is passed as an argument. In order to do that it is embedded in the code as
 424 // a constant.
 425 static nmethod* counter_overflow_helper(JavaThread* THREAD, int branch_bci, Method* m) {
 426   nmethod* osr_nm = NULL;
 427   methodHandle method(THREAD, m);
 428 
 429   RegisterMap map(THREAD, false);
 430   frame fr =  THREAD->last_frame().sender(&map);
 431   nmethod* nm = (nmethod*) fr.cb();
 432   assert(nm!= NULL && nm->is_nmethod(), "Sanity check");
 433   methodHandle enclosing_method(THREAD, nm->method());
 434 
 435   CompLevel level = (CompLevel)nm->comp_level();
 436   int bci = InvocationEntryBci;
 437   if (branch_bci != InvocationEntryBci) {
 438     // Compute destination bci
 439     address pc = method()->code_base() + branch_bci;
 440     Bytecodes::Code branch = Bytecodes::code_at(method(), pc);
 441     int offset = 0;
 442     switch (branch) {
 443       case Bytecodes::_if_icmplt: case Bytecodes::_iflt:
 444       case Bytecodes::_if_icmpgt: case Bytecodes::_ifgt:
 445       case Bytecodes::_if_icmple: case Bytecodes::_ifle:
 446       case Bytecodes::_if_icmpge: case Bytecodes::_ifge:
 447       case Bytecodes::_if_icmpeq: case Bytecodes::_if_acmpeq: case Bytecodes::_ifeq:
 448       case Bytecodes::_if_icmpne: case Bytecodes::_if_acmpne: case Bytecodes::_ifne:
 449       case Bytecodes::_ifnull: case Bytecodes::_ifnonnull: case Bytecodes::_goto:
 450         offset = (int16_t)Bytes::get_Java_u2(pc + 1);
 451         break;
 452       case Bytecodes::_goto_w:
 453         offset = Bytes::get_Java_u4(pc + 1);
 454         break;
 455       default: ;
 456     }
 457     bci = branch_bci + offset;
 458   }
 459   assert(!HAS_PENDING_EXCEPTION, "Should not have any exceptions pending");
 460   osr_nm = CompilationPolicy::policy()->event(enclosing_method, method, branch_bci, bci, level, nm, THREAD);
 461   assert(!HAS_PENDING_EXCEPTION, "Event handler should not throw any exceptions");
 462   return osr_nm;
 463 }
 464 
 465 JRT_BLOCK_ENTRY(address, Runtime1::counter_overflow(JavaThread* thread, int bci, Method* method))
 466   nmethod* osr_nm;
 467   JRT_BLOCK
 468     osr_nm = counter_overflow_helper(thread, bci, method);
 469     if (osr_nm != NULL) {
 470       RegisterMap map(thread, false);
 471       frame fr =  thread->last_frame().sender(&map);
 472       Deoptimization::deoptimize_frame(thread, fr.id());
 473     }
 474   JRT_BLOCK_END
 475   return NULL;
 476 JRT_END
 477 
 478 extern void vm_exit(int code);
 479 
 480 // Enter this method from compiled code handler below. This is where we transition
 481 // to VM mode. This is done as a helper routine so that the method called directly
 482 // from compiled code does not have to transition to VM. This allows the entry
 483 // method to see if the nmethod that we have just looked up a handler for has
 484 // been deoptimized while we were in the vm. This simplifies the assembly code
 485 // cpu directories.
 486 //
 487 // We are entering here from exception stub (via the entry method below)
 488 // If there is a compiled exception handler in this method, we will continue there;
 489 // otherwise we will unwind the stack and continue at the caller of top frame method
 490 // Note: we enter in Java using a special JRT wrapper. This wrapper allows us to
 491 // control the area where we can allow a safepoint. After we exit the safepoint area we can
 492 // check to see if the handler we are going to return is now in a nmethod that has
 493 // been deoptimized. If that is the case we return the deopt blob
 494 // unpack_with_exception entry instead. This makes life for the exception blob easier
 495 // because making that same check and diverting is painful from assembly language.
 496 JRT_ENTRY_NO_ASYNC(static address, exception_handler_for_pc_helper(JavaThread* thread, oopDesc* ex, address pc, nmethod*& nm))
 497   // Reset method handle flag.
 498   thread->set_is_method_handle_return(false);
 499 
 500   Handle exception(thread, ex);
 501   nm = CodeCache::find_nmethod(pc);
 502   assert(nm != NULL, "this is not an nmethod");
 503   // Adjust the pc as needed/
 504   if (nm->is_deopt_pc(pc)) {
 505     RegisterMap map(thread, false);
 506     frame exception_frame = thread->last_frame().sender(&map);
 507     // if the frame isn't deopted then pc must not correspond to the caller of last_frame
 508     assert(exception_frame.is_deoptimized_frame(), "must be deopted");
 509     pc = exception_frame.pc();
 510   }
 511 #ifdef ASSERT
 512   assert(exception.not_null(), "NULL exceptions should be handled by throw_exception");
 513   // Check that exception is a subclass of Throwable, otherwise we have a VerifyError
 514   if (!(exception->is_a(SystemDictionary::Throwable_klass()))) {
 515     if (ExitVMOnVerifyError) vm_exit(-1);
 516     ShouldNotReachHere();
 517   }
 518 #endif
 519 
 520   // Check the stack guard pages and reenable them if necessary and there is
 521   // enough space on the stack to do so.  Use fast exceptions only if the guard
 522   // pages are enabled.
 523   bool guard_pages_enabled = thread->stack_guards_enabled();
 524   if (!guard_pages_enabled) guard_pages_enabled = thread->reguard_stack();
 525 
 526   if (JvmtiExport::can_post_on_exceptions()) {
 527     // To ensure correct notification of exception catches and throws
 528     // we have to deoptimize here.  If we attempted to notify the
 529     // catches and throws during this exception lookup it's possible
 530     // we could deoptimize on the way out of the VM and end back in
 531     // the interpreter at the throw site.  This would result in double
 532     // notifications since the interpreter would also notify about
 533     // these same catches and throws as it unwound the frame.
 534 
 535     RegisterMap reg_map(thread);
 536     frame stub_frame = thread->last_frame();
 537     frame caller_frame = stub_frame.sender(&reg_map);
 538 
 539     // We don't really want to deoptimize the nmethod itself since we
 540     // can actually continue in the exception handler ourselves but I
 541     // don't see an easy way to have the desired effect.
 542     Deoptimization::deoptimize_frame(thread, caller_frame.id());
 543     assert(caller_is_deopted(), "Must be deoptimized");
 544 
 545     return SharedRuntime::deopt_blob()->unpack_with_exception_in_tls();
 546   }
 547 
 548   // ExceptionCache is used only for exceptions at call sites and not for implicit exceptions
 549   if (guard_pages_enabled) {
 550     address fast_continuation = nm->handler_for_exception_and_pc(exception, pc);
 551     if (fast_continuation != NULL) {
 552       // Set flag if return address is a method handle call site.
 553       thread->set_is_method_handle_return(nm->is_method_handle_return(pc));
 554       return fast_continuation;
 555     }
 556   }
 557 
 558   // If the stack guard pages are enabled, check whether there is a handler in
 559   // the current method.  Otherwise (guard pages disabled), force an unwind and
 560   // skip the exception cache update (i.e., just leave continuation==NULL).
 561   address continuation = NULL;
 562   if (guard_pages_enabled) {
 563 
 564     // New exception handling mechanism can support inlined methods
 565     // with exception handlers since the mappings are from PC to PC
 566 
 567     // debugging support
 568     // tracing
 569     if (log_is_enabled(Info, exceptions)) {
 570       ResourceMark rm;
 571       stringStream tempst;
 572       assert(nm->method() != NULL, "Unexpected NULL method()");
 573       tempst.print("compiled method <%s>\n"
 574                    " at PC" INTPTR_FORMAT " for thread " INTPTR_FORMAT,
 575                    nm->method()->print_value_string(), p2i(pc), p2i(thread));
 576       Exceptions::log_exception(exception, tempst);
 577     }
 578     // for AbortVMOnException flag
 579     Exceptions::debug_check_abort(exception);
 580 
 581     // Clear out the exception oop and pc since looking up an
 582     // exception handler can cause class loading, which might throw an
 583     // exception and those fields are expected to be clear during
 584     // normal bytecode execution.
 585     thread->clear_exception_oop_and_pc();
 586 
 587     bool recursive_exception = false;
 588     continuation = SharedRuntime::compute_compiled_exc_handler(nm, pc, exception, false, false, recursive_exception);
 589     // If an exception was thrown during exception dispatch, the exception oop may have changed
 590     thread->set_exception_oop(exception());
 591     thread->set_exception_pc(pc);
 592 
 593     // the exception cache is used only by non-implicit exceptions
 594     // Update the exception cache only when there didn't happen
 595     // another exception during the computation of the compiled
 596     // exception handler. Checking for exception oop equality is not
 597     // sufficient because some exceptions are pre-allocated and reused.
 598     if (continuation != NULL && !recursive_exception) {
 599       nm->add_handler_for_exception_and_pc(exception, pc, continuation);
 600     }
 601   }
 602 
 603   thread->set_vm_result(exception());
 604   // Set flag if return address is a method handle call site.
 605   thread->set_is_method_handle_return(nm->is_method_handle_return(pc));
 606 
 607   if (log_is_enabled(Info, exceptions)) {
 608     ResourceMark rm;
 609     log_info(exceptions)("Thread " PTR_FORMAT " continuing at PC " PTR_FORMAT
 610                          " for exception thrown at PC " PTR_FORMAT,
 611                          p2i(thread), p2i(continuation), p2i(pc));
 612   }
 613 
 614   return continuation;
 615 JRT_END
 616 
 617 // Enter this method from compiled code only if there is a Java exception handler
 618 // in the method handling the exception.
 619 // We are entering here from exception stub. We don't do a normal VM transition here.
 620 // We do it in a helper. This is so we can check to see if the nmethod we have just
 621 // searched for an exception handler has been deoptimized in the meantime.
 622 address Runtime1::exception_handler_for_pc(JavaThread* thread) {
 623   oop exception = thread->exception_oop();
 624   address pc = thread->exception_pc();
 625   // Still in Java mode
 626   DEBUG_ONLY(ResetNoHandleMark rnhm);
 627   nmethod* nm = NULL;
 628   address continuation = NULL;
 629   {
 630     // Enter VM mode by calling the helper
 631     ResetNoHandleMark rnhm;
 632     continuation = exception_handler_for_pc_helper(thread, exception, pc, nm);
 633   }
 634   // Back in JAVA, use no oops DON'T safepoint
 635 
 636   // Now check to see if the nmethod we were called from is now deoptimized.
 637   // If so we must return to the deopt blob and deoptimize the nmethod
 638   if (nm != NULL && caller_is_deopted()) {
 639     continuation = SharedRuntime::deopt_blob()->unpack_with_exception_in_tls();
 640   }
 641 
 642   assert(continuation != NULL, "no handler found");
 643   return continuation;
 644 }
 645 
 646 
 647 JRT_ENTRY(void, Runtime1::throw_range_check_exception(JavaThread* thread, int index, arrayOopDesc* a))
 648   NOT_PRODUCT(_throw_range_check_exception_count++;)
 649   const int len = 35;
 650   assert(len < strlen("Index %d out of bounds for length %d"), "Must allocate more space for message.");
 651   char message[2 * jintAsStringSize + len];
 652   sprintf(message, "Index %d out of bounds for length %d", index, a->length());
 653   SharedRuntime::throw_and_post_jvmti_exception(thread, vmSymbols::java_lang_ArrayIndexOutOfBoundsException(), message);
 654 JRT_END
 655 
 656 
 657 JRT_ENTRY(void, Runtime1::throw_index_exception(JavaThread* thread, int index))
 658   NOT_PRODUCT(_throw_index_exception_count++;)
 659   char message[16];
 660   sprintf(message, "%d", index);
 661   SharedRuntime::throw_and_post_jvmti_exception(thread, vmSymbols::java_lang_IndexOutOfBoundsException(), message);
 662 JRT_END
 663 
 664 
 665 JRT_ENTRY(void, Runtime1::throw_div0_exception(JavaThread* thread))
 666   NOT_PRODUCT(_throw_div0_exception_count++;)
 667   SharedRuntime::throw_and_post_jvmti_exception(thread, vmSymbols::java_lang_ArithmeticException(), "/ by zero");
 668 JRT_END
 669 
 670 
 671 JRT_ENTRY(void, Runtime1::throw_null_pointer_exception(JavaThread* thread))
 672   NOT_PRODUCT(_throw_null_pointer_exception_count++;)
 673   SharedRuntime::throw_and_post_jvmti_exception(thread, vmSymbols::java_lang_NullPointerException());
 674 JRT_END
 675 
 676 
 677 JRT_ENTRY(void, Runtime1::throw_class_cast_exception(JavaThread* thread, oopDesc* object))
 678   NOT_PRODUCT(_throw_class_cast_exception_count++;)
 679   ResourceMark rm(thread);
 680   char* message = SharedRuntime::generate_class_cast_message(
 681     thread, object->klass());
 682   SharedRuntime::throw_and_post_jvmti_exception(
 683     thread, vmSymbols::java_lang_ClassCastException(), message);
 684 JRT_END
 685 
 686 
 687 JRT_ENTRY(void, Runtime1::throw_incompatible_class_change_error(JavaThread* thread))
 688   NOT_PRODUCT(_throw_incompatible_class_change_error_count++;)
 689   ResourceMark rm(thread);
 690   SharedRuntime::throw_and_post_jvmti_exception(thread, vmSymbols::java_lang_IncompatibleClassChangeError());
 691 JRT_END
 692 
 693 
 694 JRT_ENTRY_NO_ASYNC(void, Runtime1::monitorenter(JavaThread* thread, oopDesc* obj, BasicObjectLock* lock))
 695   NOT_PRODUCT(_monitorenter_slowcase_cnt++;)
 696   if (PrintBiasedLockingStatistics) {
 697     Atomic::inc(BiasedLocking::slow_path_entry_count_addr());
 698   }
 699   Handle h_obj(thread, obj);
 700   if (UseBiasedLocking) {
 701     // Retry fast entry if bias is revoked to avoid unnecessary inflation
 702     ObjectSynchronizer::fast_enter(h_obj, lock->lock(), true, CHECK);
 703   } else {
 704     if (UseFastLocking) {
 705       // When using fast locking, the compiled code has already tried the fast case
 706       assert(obj == lock->obj(), "must match");
 707       ObjectSynchronizer::slow_enter(h_obj, lock->lock(), THREAD);
 708     } else {
 709       lock->set_obj(obj);
 710       ObjectSynchronizer::fast_enter(h_obj, lock->lock(), false, THREAD);
 711     }
 712   }
 713 JRT_END
 714 
 715 
 716 JRT_LEAF(void, Runtime1::monitorexit(JavaThread* thread, BasicObjectLock* lock))
 717   NOT_PRODUCT(_monitorexit_slowcase_cnt++;)
 718   assert(thread == JavaThread::current(), "threads must correspond");
 719   assert(thread->last_Java_sp(), "last_Java_sp must be set");
 720   // monitorexit is non-blocking (leaf routine) => no exceptions can be thrown
 721   EXCEPTION_MARK;
 722 
 723   oop obj = lock->obj();
 724   assert(oopDesc::is_oop(obj), "must be NULL or an object");
 725   if (UseFastLocking) {
 726     // When using fast locking, the compiled code has already tried the fast case
 727     ObjectSynchronizer::slow_exit(obj, lock->lock(), THREAD);
 728   } else {
 729     ObjectSynchronizer::fast_exit(obj, lock->lock(), THREAD);
 730   }
 731 JRT_END
 732 
 733 // Cf. OptoRuntime::deoptimize_caller_frame
 734 JRT_ENTRY(void, Runtime1::deoptimize(JavaThread* thread, jint trap_request))
 735   // Called from within the owner thread, so no need for safepoint
 736   RegisterMap reg_map(thread, false);
 737   frame stub_frame = thread->last_frame();
 738   assert(stub_frame.is_runtime_frame(), "Sanity check");
 739   frame caller_frame = stub_frame.sender(&reg_map);
 740   nmethod* nm = caller_frame.cb()->as_nmethod_or_null();
 741   assert(nm != NULL, "Sanity check");
 742   methodHandle method(thread, nm->method());
 743   assert(nm == CodeCache::find_nmethod(caller_frame.pc()), "Should be the same");
 744   Deoptimization::DeoptAction action = Deoptimization::trap_request_action(trap_request);
 745   Deoptimization::DeoptReason reason = Deoptimization::trap_request_reason(trap_request);
 746 
 747   if (action == Deoptimization::Action_make_not_entrant) {
 748     if (nm->make_not_entrant()) {
 749       if (reason == Deoptimization::Reason_tenured) {
 750         MethodData* trap_mdo = Deoptimization::get_method_data(thread, method, true /*create_if_missing*/);
 751         if (trap_mdo != NULL) {
 752           trap_mdo->inc_tenure_traps();
 753         }
 754       }
 755     }
 756   }
 757 
 758   // Deoptimize the caller frame.
 759   Deoptimization::deoptimize_frame(thread, caller_frame.id());
 760   // Return to the now deoptimized frame.
 761 JRT_END
 762 
 763 
 764 #ifndef DEOPTIMIZE_WHEN_PATCHING
 765 
 766 static Klass* resolve_field_return_klass(const methodHandle& caller, int bci, TRAPS) {
 767   Bytecode_field field_access(caller, bci);
 768   // This can be static or non-static field access
 769   Bytecodes::Code code       = field_access.code();
 770 
 771   // We must load class, initialize class and resolve the field
 772   fieldDescriptor result; // initialize class if needed
 773   constantPoolHandle constants(THREAD, caller->constants());
 774   LinkResolver::resolve_field_access(result, constants, field_access.index(), caller, Bytecodes::java_code(code), CHECK_NULL);
 775   return result.field_holder();
 776 }
 777 
 778 
 779 //
 780 // This routine patches sites where a class wasn't loaded or
 781 // initialized at the time the code was generated.  It handles
 782 // references to classes, fields and forcing of initialization.  Most
 783 // of the cases are straightforward and involving simply forcing
 784 // resolution of a class, rewriting the instruction stream with the
 785 // needed constant and replacing the call in this function with the
 786 // patched code.  The case for static field is more complicated since
 787 // the thread which is in the process of initializing a class can
 788 // access it's static fields but other threads can't so the code
 789 // either has to deoptimize when this case is detected or execute a
 790 // check that the current thread is the initializing thread.  The
 791 // current
 792 //
 793 // Patches basically look like this:
 794 //
 795 //
 796 // patch_site: jmp patch stub     ;; will be patched
 797 // continue:   ...
 798 //             ...
 799 //             ...
 800 //             ...
 801 //
 802 // They have a stub which looks like this:
 803 //
 804 //             ;; patch body
 805 //             movl <const>, reg           (for class constants)
 806 //        <or> movl [reg1 + <const>], reg  (for field offsets)
 807 //        <or> movl reg, [reg1 + <const>]  (for field offsets)
 808 //             <being_init offset> <bytes to copy> <bytes to skip>
 809 // patch_stub: call Runtime1::patch_code (through a runtime stub)
 810 //             jmp patch_site
 811 //
 812 //
 813 // A normal patch is done by rewriting the patch body, usually a move,
 814 // and then copying it into place over top of the jmp instruction
 815 // being careful to flush caches and doing it in an MP-safe way.  The
 816 // constants following the patch body are used to find various pieces
 817 // of the patch relative to the call site for Runtime1::patch_code.
 818 // The case for getstatic and putstatic is more complicated because
 819 // getstatic and putstatic have special semantics when executing while
 820 // the class is being initialized.  getstatic/putstatic on a class
 821 // which is being_initialized may be executed by the initializing
 822 // thread but other threads have to block when they execute it.  This
 823 // is accomplished in compiled code by executing a test of the current
 824 // thread against the initializing thread of the class.  It's emitted
 825 // as boilerplate in their stub which allows the patched code to be
 826 // executed before it's copied back into the main body of the nmethod.
 827 //
 828 // being_init: get_thread(<tmp reg>
 829 //             cmpl [reg1 + <init_thread_offset>], <tmp reg>
 830 //             jne patch_stub
 831 //             movl [reg1 + <const>], reg  (for field offsets)  <or>
 832 //             movl reg, [reg1 + <const>]  (for field offsets)
 833 //             jmp continue
 834 //             <being_init offset> <bytes to copy> <bytes to skip>
 835 // patch_stub: jmp Runtim1::patch_code (through a runtime stub)
 836 //             jmp patch_site
 837 //
 838 // If the class is being initialized the patch body is rewritten and
 839 // the patch site is rewritten to jump to being_init, instead of
 840 // patch_stub.  Whenever this code is executed it checks the current
 841 // thread against the intializing thread so other threads will enter
 842 // the runtime and end up blocked waiting the class to finish
 843 // initializing inside the calls to resolve_field below.  The
 844 // initializing class will continue on it's way.  Once the class is
 845 // fully_initialized, the intializing_thread of the class becomes
 846 // NULL, so the next thread to execute this code will fail the test,
 847 // call into patch_code and complete the patching process by copying
 848 // the patch body back into the main part of the nmethod and resume
 849 // executing.
 850 //
 851 //
 852 
 853 JRT_ENTRY(void, Runtime1::patch_code(JavaThread* thread, Runtime1::StubID stub_id ))
 854   NOT_PRODUCT(_patch_code_slowcase_cnt++;)
 855 
 856   ResourceMark rm(thread);
 857   RegisterMap reg_map(thread, false);
 858   frame runtime_frame = thread->last_frame();
 859   frame caller_frame = runtime_frame.sender(&reg_map);
 860 
 861   // last java frame on stack
 862   vframeStream vfst(thread, true);
 863   assert(!vfst.at_end(), "Java frame must exist");
 864 
 865   methodHandle caller_method(THREAD, vfst.method());
 866   // Note that caller_method->code() may not be same as caller_code because of OSR's
 867   // Note also that in the presence of inlining it is not guaranteed
 868   // that caller_method() == caller_code->method()
 869 
 870   int bci = vfst.bci();
 871   Bytecodes::Code code = caller_method()->java_code_at(bci);
 872 
 873   // this is used by assertions in the access_field_patching_id
 874   BasicType patch_field_type = T_ILLEGAL;
 875   bool deoptimize_for_volatile = false;
 876   bool deoptimize_for_atomic = false;
 877   int patch_field_offset = -1;
 878   Klass* init_klass = NULL; // klass needed by load_klass_patching code
 879   Klass* load_klass = NULL; // klass needed by load_klass_patching code
 880   Handle mirror(THREAD, NULL);                    // oop needed by load_mirror_patching code
 881   Handle appendix(THREAD, NULL);                  // oop needed by appendix_patching code
 882   bool load_klass_or_mirror_patch_id =
 883     (stub_id == Runtime1::load_klass_patching_id || stub_id == Runtime1::load_mirror_patching_id);
 884 
 885   if (stub_id == Runtime1::access_field_patching_id) {
 886 
 887     Bytecode_field field_access(caller_method, bci);
 888     fieldDescriptor result; // initialize class if needed
 889     Bytecodes::Code code = field_access.code();
 890     constantPoolHandle constants(THREAD, caller_method->constants());
 891     LinkResolver::resolve_field_access(result, constants, field_access.index(), caller_method, Bytecodes::java_code(code), CHECK);
 892     patch_field_offset = result.offset();
 893 
 894     // If we're patching a field which is volatile then at compile it
 895     // must not have been know to be volatile, so the generated code
 896     // isn't correct for a volatile reference.  The nmethod has to be
 897     // deoptimized so that the code can be regenerated correctly.
 898     // This check is only needed for access_field_patching since this
 899     // is the path for patching field offsets.  load_klass is only
 900     // used for patching references to oops which don't need special
 901     // handling in the volatile case.
 902 
 903     deoptimize_for_volatile = result.access_flags().is_volatile();
 904 
 905     // If we are patching a field which should be atomic, then
 906     // the generated code is not correct either, force deoptimizing.
 907     // We need to only cover T_LONG and T_DOUBLE fields, as we can
 908     // break access atomicity only for them.
 909 
 910     // Strictly speaking, the deoptimizaation on 64-bit platforms
 911     // is unnecessary, and T_LONG stores on 32-bit platforms need
 912     // to be handled by special patching code when AlwaysAtomicAccesses
 913     // becomes product feature. At this point, we are still going
 914     // for the deoptimization for consistency against volatile
 915     // accesses.
 916 
 917     patch_field_type = result.field_type();
 918     deoptimize_for_atomic = (AlwaysAtomicAccesses && (patch_field_type == T_DOUBLE || patch_field_type == T_LONG));
 919 
 920   } else if (load_klass_or_mirror_patch_id) {
 921     Klass* k = NULL;
 922     switch (code) {
 923       case Bytecodes::_putstatic:
 924       case Bytecodes::_getstatic:
 925         { Klass* klass = resolve_field_return_klass(caller_method, bci, CHECK);
 926           init_klass = klass;
 927           mirror = Handle(THREAD, klass->java_mirror());
 928         }
 929         break;
 930       case Bytecodes::_new:
 931         { Bytecode_new bnew(caller_method(), caller_method->bcp_from(bci));
 932           k = caller_method->constants()->klass_at(bnew.index(), CHECK);
 933         }
 934         break;
 935       case Bytecodes::_multianewarray:
 936         { Bytecode_multianewarray mna(caller_method(), caller_method->bcp_from(bci));
 937           k = caller_method->constants()->klass_at(mna.index(), CHECK);
 938         }
 939         break;
 940       case Bytecodes::_instanceof:
 941         { Bytecode_instanceof io(caller_method(), caller_method->bcp_from(bci));
 942           k = caller_method->constants()->klass_at(io.index(), CHECK);
 943         }
 944         break;
 945       case Bytecodes::_checkcast:
 946         { Bytecode_checkcast cc(caller_method(), caller_method->bcp_from(bci));
 947           k = caller_method->constants()->klass_at(cc.index(), CHECK);
 948         }
 949         break;
 950       case Bytecodes::_anewarray:
 951         { Bytecode_anewarray anew(caller_method(), caller_method->bcp_from(bci));
 952           Klass* ek = caller_method->constants()->klass_at(anew.index(), CHECK);
 953           k = ek->array_klass(CHECK);
 954         }
 955         break;
 956       case Bytecodes::_ldc:
 957       case Bytecodes::_ldc_w:
 958         {
 959           Bytecode_loadconstant cc(caller_method, bci);
 960           oop m = cc.resolve_constant(CHECK);
 961           mirror = Handle(THREAD, m);
 962         }
 963         break;
 964       default: fatal("unexpected bytecode for load_klass_or_mirror_patch_id");
 965     }
 966     load_klass = k;
 967   } else if (stub_id == load_appendix_patching_id) {
 968     Bytecode_invoke bytecode(caller_method, bci);
 969     Bytecodes::Code bc = bytecode.invoke_code();
 970 
 971     CallInfo info;
 972     constantPoolHandle pool(thread, caller_method->constants());
 973     int index = bytecode.index();
 974     LinkResolver::resolve_invoke(info, Handle(), pool, index, bc, CHECK);
 975     switch (bc) {
 976       case Bytecodes::_invokehandle: {
 977         int cache_index = ConstantPool::decode_cpcache_index(index, true);
 978         assert(cache_index >= 0 && cache_index < pool->cache()->length(), "unexpected cache index");
 979         ConstantPoolCacheEntry* cpce = pool->cache()->entry_at(cache_index);
 980         cpce->set_method_handle(pool, info);
 981         appendix = Handle(THREAD, cpce->appendix_if_resolved(pool)); // just in case somebody already resolved the entry
 982         break;
 983       }
 984       case Bytecodes::_invokedynamic: {
 985         ConstantPoolCacheEntry* cpce = pool->invokedynamic_cp_cache_entry_at(index);
 986         cpce->set_dynamic_call(pool, info);
 987         appendix = Handle(THREAD, cpce->appendix_if_resolved(pool)); // just in case somebody already resolved the entry
 988         break;
 989       }
 990       default: fatal("unexpected bytecode for load_appendix_patching_id");
 991     }
 992   } else {
 993     ShouldNotReachHere();
 994   }
 995 
 996   if (deoptimize_for_volatile || deoptimize_for_atomic) {
 997     // At compile time we assumed the field wasn't volatile/atomic but after
 998     // loading it turns out it was volatile/atomic so we have to throw the
 999     // compiled code out and let it be regenerated.
1000     if (TracePatching) {
1001       if (deoptimize_for_volatile) {
1002         tty->print_cr("Deoptimizing for patching volatile field reference");
1003       }
1004       if (deoptimize_for_atomic) {
1005         tty->print_cr("Deoptimizing for patching atomic field reference");
1006       }
1007     }
1008 
1009     // It's possible the nmethod was invalidated in the last
1010     // safepoint, but if it's still alive then make it not_entrant.
1011     nmethod* nm = CodeCache::find_nmethod(caller_frame.pc());
1012     if (nm != NULL) {
1013       nm->make_not_entrant();
1014     }
1015 
1016     Deoptimization::deoptimize_frame(thread, caller_frame.id());
1017 
1018     // Return to the now deoptimized frame.
1019   }
1020 
1021   // Now copy code back
1022 
1023   {
1024     MutexLockerEx ml_patch (Patching_lock, Mutex::_no_safepoint_check_flag);
1025     //
1026     // Deoptimization may have happened while we waited for the lock.
1027     // In that case we don't bother to do any patching we just return
1028     // and let the deopt happen
1029     if (!caller_is_deopted()) {
1030       NativeGeneralJump* jump = nativeGeneralJump_at(caller_frame.pc());
1031       address instr_pc = jump->jump_destination();
1032       NativeInstruction* ni = nativeInstruction_at(instr_pc);
1033       if (ni->is_jump() ) {
1034         // the jump has not been patched yet
1035         // The jump destination is slow case and therefore not part of the stubs
1036         // (stubs are only for StaticCalls)
1037 
1038         // format of buffer
1039         //    ....
1040         //    instr byte 0     <-- copy_buff
1041         //    instr byte 1
1042         //    ..
1043         //    instr byte n-1
1044         //      n
1045         //    ....             <-- call destination
1046 
1047         address stub_location = caller_frame.pc() + PatchingStub::patch_info_offset();
1048         unsigned char* byte_count = (unsigned char*) (stub_location - 1);
1049         unsigned char* byte_skip = (unsigned char*) (stub_location - 2);
1050         unsigned char* being_initialized_entry_offset = (unsigned char*) (stub_location - 3);
1051         address copy_buff = stub_location - *byte_skip - *byte_count;
1052         address being_initialized_entry = stub_location - *being_initialized_entry_offset;
1053         if (TracePatching) {
1054           ttyLocker ttyl;
1055           tty->print_cr(" Patching %s at bci %d at address " INTPTR_FORMAT "  (%s)", Bytecodes::name(code), bci,
1056                         p2i(instr_pc), (stub_id == Runtime1::access_field_patching_id) ? "field" : "klass");
1057           nmethod* caller_code = CodeCache::find_nmethod(caller_frame.pc());
1058           assert(caller_code != NULL, "nmethod not found");
1059 
1060           // NOTE we use pc() not original_pc() because we already know they are
1061           // identical otherwise we'd have never entered this block of code
1062 
1063           const ImmutableOopMap* map = caller_code->oop_map_for_return_address(caller_frame.pc());
1064           assert(map != NULL, "null check");
1065           map->print();
1066           tty->cr();
1067 
1068           Disassembler::decode(copy_buff, copy_buff + *byte_count, tty);
1069         }
1070         // depending on the code below, do_patch says whether to copy the patch body back into the nmethod
1071         bool do_patch = true;
1072         if (stub_id == Runtime1::access_field_patching_id) {
1073           // The offset may not be correct if the class was not loaded at code generation time.
1074           // Set it now.
1075           NativeMovRegMem* n_move = nativeMovRegMem_at(copy_buff);
1076           assert(n_move->offset() == 0 || (n_move->offset() == 4 && (patch_field_type == T_DOUBLE || patch_field_type == T_LONG)), "illegal offset for type");
1077           assert(patch_field_offset >= 0, "illegal offset");
1078           n_move->add_offset_in_bytes(patch_field_offset);
1079         } else if (load_klass_or_mirror_patch_id) {
1080           // If a getstatic or putstatic is referencing a klass which
1081           // isn't fully initialized, the patch body isn't copied into
1082           // place until initialization is complete.  In this case the
1083           // patch site is setup so that any threads besides the
1084           // initializing thread are forced to come into the VM and
1085           // block.
1086           do_patch = (code != Bytecodes::_getstatic && code != Bytecodes::_putstatic) ||
1087                      InstanceKlass::cast(init_klass)->is_initialized();
1088           NativeGeneralJump* jump = nativeGeneralJump_at(instr_pc);
1089           if (jump->jump_destination() == being_initialized_entry) {
1090             assert(do_patch == true, "initialization must be complete at this point");
1091           } else {
1092             // patch the instruction <move reg, klass>
1093             NativeMovConstReg* n_copy = nativeMovConstReg_at(copy_buff);
1094 
1095             assert(n_copy->data() == 0 ||
1096                    n_copy->data() == (intptr_t)Universe::non_oop_word(),
1097                    "illegal init value");
1098             if (stub_id == Runtime1::load_klass_patching_id) {
1099               assert(load_klass != NULL, "klass not set");
1100               n_copy->set_data((intx) (load_klass));
1101             } else {
1102               assert(mirror() != NULL, "klass not set");
1103               // Don't need a G1 pre-barrier here since we assert above that data isn't an oop.
1104               n_copy->set_data(cast_from_oop<intx>(mirror()));
1105             }
1106 
1107             if (TracePatching) {
1108               Disassembler::decode(copy_buff, copy_buff + *byte_count, tty);
1109             }
1110           }
1111         } else if (stub_id == Runtime1::load_appendix_patching_id) {
1112           NativeMovConstReg* n_copy = nativeMovConstReg_at(copy_buff);
1113           assert(n_copy->data() == 0 ||
1114                  n_copy->data() == (intptr_t)Universe::non_oop_word(),
1115                  "illegal init value");
1116           n_copy->set_data(cast_from_oop<intx>(appendix()));
1117 
1118           if (TracePatching) {
1119             Disassembler::decode(copy_buff, copy_buff + *byte_count, tty);
1120           }
1121         } else {
1122           ShouldNotReachHere();
1123         }
1124 
1125 #if defined(SPARC) || defined(PPC32)
1126         if (load_klass_or_mirror_patch_id ||
1127             stub_id == Runtime1::load_appendix_patching_id) {
1128           // Update the location in the nmethod with the proper
1129           // metadata.  When the code was generated, a NULL was stuffed
1130           // in the metadata table and that table needs to be update to
1131           // have the right value.  On intel the value is kept
1132           // directly in the instruction instead of in the metadata
1133           // table, so set_data above effectively updated the value.
1134           nmethod* nm = CodeCache::find_nmethod(instr_pc);
1135           assert(nm != NULL, "invalid nmethod_pc");
1136           RelocIterator mds(nm, copy_buff, copy_buff + 1);
1137           bool found = false;
1138           while (mds.next() && !found) {
1139             if (mds.type() == relocInfo::oop_type) {
1140               assert(stub_id == Runtime1::load_mirror_patching_id ||
1141                      stub_id == Runtime1::load_appendix_patching_id, "wrong stub id");
1142               oop_Relocation* r = mds.oop_reloc();
1143               oop* oop_adr = r->oop_addr();
1144               *oop_adr = stub_id == Runtime1::load_mirror_patching_id ? mirror() : appendix();
1145               r->fix_oop_relocation();
1146               found = true;
1147             } else if (mds.type() == relocInfo::metadata_type) {
1148               assert(stub_id == Runtime1::load_klass_patching_id, "wrong stub id");
1149               metadata_Relocation* r = mds.metadata_reloc();
1150               Metadata** metadata_adr = r->metadata_addr();
1151               *metadata_adr = load_klass;
1152               r->fix_metadata_relocation();
1153               found = true;
1154             }
1155           }
1156           assert(found, "the metadata must exist!");
1157         }
1158 #endif
1159         if (do_patch) {
1160           // replace instructions
1161           // first replace the tail, then the call
1162 #ifdef ARM
1163           if((load_klass_or_mirror_patch_id ||
1164               stub_id == Runtime1::load_appendix_patching_id) &&
1165               nativeMovConstReg_at(copy_buff)->is_pc_relative()) {
1166             nmethod* nm = CodeCache::find_nmethod(instr_pc);
1167             address addr = NULL;
1168             assert(nm != NULL, "invalid nmethod_pc");
1169             RelocIterator mds(nm, copy_buff, copy_buff + 1);
1170             while (mds.next()) {
1171               if (mds.type() == relocInfo::oop_type) {
1172                 assert(stub_id == Runtime1::load_mirror_patching_id ||
1173                        stub_id == Runtime1::load_appendix_patching_id, "wrong stub id");
1174                 oop_Relocation* r = mds.oop_reloc();
1175                 addr = (address)r->oop_addr();
1176                 break;
1177               } else if (mds.type() == relocInfo::metadata_type) {
1178                 assert(stub_id == Runtime1::load_klass_patching_id, "wrong stub id");
1179                 metadata_Relocation* r = mds.metadata_reloc();
1180                 addr = (address)r->metadata_addr();
1181                 break;
1182               }
1183             }
1184             assert(addr != NULL, "metadata relocation must exist");
1185             copy_buff -= *byte_count;
1186             NativeMovConstReg* n_copy2 = nativeMovConstReg_at(copy_buff);
1187             n_copy2->set_pc_relative_offset(addr, instr_pc);
1188           }
1189 #endif
1190 
1191           for (int i = NativeGeneralJump::instruction_size; i < *byte_count; i++) {
1192             address ptr = copy_buff + i;
1193             int a_byte = (*ptr) & 0xFF;
1194             address dst = instr_pc + i;
1195             *(unsigned char*)dst = (unsigned char) a_byte;
1196           }
1197           ICache::invalidate_range(instr_pc, *byte_count);
1198           NativeGeneralJump::replace_mt_safe(instr_pc, copy_buff);
1199 
1200           if (load_klass_or_mirror_patch_id ||
1201               stub_id == Runtime1::load_appendix_patching_id) {
1202             relocInfo::relocType rtype =
1203               (stub_id == Runtime1::load_klass_patching_id) ?
1204                                    relocInfo::metadata_type :
1205                                    relocInfo::oop_type;
1206             // update relocInfo to metadata
1207             nmethod* nm = CodeCache::find_nmethod(instr_pc);
1208             assert(nm != NULL, "invalid nmethod_pc");
1209 
1210             // The old patch site is now a move instruction so update
1211             // the reloc info so that it will get updated during
1212             // future GCs.
1213             RelocIterator iter(nm, (address)instr_pc, (address)(instr_pc + 1));
1214             relocInfo::change_reloc_info_for_address(&iter, (address) instr_pc,
1215                                                      relocInfo::none, rtype);
1216 #ifdef SPARC
1217             // Sparc takes two relocations for an metadata so update the second one.
1218             address instr_pc2 = instr_pc + NativeMovConstReg::add_offset;
1219             RelocIterator iter2(nm, instr_pc2, instr_pc2 + 1);
1220             relocInfo::change_reloc_info_for_address(&iter2, (address) instr_pc2,
1221                                                      relocInfo::none, rtype);
1222 #endif
1223 #ifdef PPC32
1224           { address instr_pc2 = instr_pc + NativeMovConstReg::lo_offset;
1225             RelocIterator iter2(nm, instr_pc2, instr_pc2 + 1);
1226             relocInfo::change_reloc_info_for_address(&iter2, (address) instr_pc2,
1227                                                      relocInfo::none, rtype);
1228           }
1229 #endif
1230           }
1231 
1232         } else {
1233           ICache::invalidate_range(copy_buff, *byte_count);
1234           NativeGeneralJump::insert_unconditional(instr_pc, being_initialized_entry);
1235         }
1236       }
1237     }
1238   }
1239 
1240   // If we are patching in a non-perm oop, make sure the nmethod
1241   // is on the right list.
1242   if (ScavengeRootsInCode) {
1243     MutexLockerEx ml_code (CodeCache_lock, Mutex::_no_safepoint_check_flag);
1244     nmethod* nm = CodeCache::find_nmethod(caller_frame.pc());
1245     guarantee(nm != NULL, "only nmethods can contain non-perm oops");
1246 
1247     // Since we've patched some oops in the nmethod,
1248     // (re)register it with the heap.
1249     Universe::heap()->register_nmethod(nm);
1250   }
1251 JRT_END
1252 
1253 #else // DEOPTIMIZE_WHEN_PATCHING
1254 
1255 JRT_ENTRY(void, Runtime1::patch_code(JavaThread* thread, Runtime1::StubID stub_id ))
1256   RegisterMap reg_map(thread, false);
1257 
1258   NOT_PRODUCT(_patch_code_slowcase_cnt++;)
1259   if (TracePatching) {
1260     tty->print_cr("Deoptimizing because patch is needed");
1261   }
1262 
1263   frame runtime_frame = thread->last_frame();
1264   frame caller_frame = runtime_frame.sender(&reg_map);
1265 
1266   // It's possible the nmethod was invalidated in the last
1267   // safepoint, but if it's still alive then make it not_entrant.
1268   nmethod* nm = CodeCache::find_nmethod(caller_frame.pc());
1269   if (nm != NULL) {
1270     nm->make_not_entrant();
1271   }
1272 
1273   Deoptimization::deoptimize_frame(thread, caller_frame.id());
1274 
1275   // Return to the now deoptimized frame.
1276 JRT_END
1277 
1278 #endif // DEOPTIMIZE_WHEN_PATCHING
1279 
1280 //
1281 // Entry point for compiled code. We want to patch a nmethod.
1282 // We don't do a normal VM transition here because we want to
1283 // know after the patching is complete and any safepoint(s) are taken
1284 // if the calling nmethod was deoptimized. We do this by calling a
1285 // helper method which does the normal VM transition and when it
1286 // completes we can check for deoptimization. This simplifies the
1287 // assembly code in the cpu directories.
1288 //
1289 int Runtime1::move_klass_patching(JavaThread* thread) {
1290 //
1291 // NOTE: we are still in Java
1292 //
1293   Thread* THREAD = thread;
1294   debug_only(NoHandleMark nhm;)
1295   {
1296     // Enter VM mode
1297 
1298     ResetNoHandleMark rnhm;
1299     patch_code(thread, load_klass_patching_id);
1300   }
1301   // Back in JAVA, use no oops DON'T safepoint
1302 
1303   // Return true if calling code is deoptimized
1304 
1305   return caller_is_deopted();
1306 }
1307 
1308 int Runtime1::move_mirror_patching(JavaThread* thread) {
1309 //
1310 // NOTE: we are still in Java
1311 //
1312   Thread* THREAD = thread;
1313   debug_only(NoHandleMark nhm;)
1314   {
1315     // Enter VM mode
1316 
1317     ResetNoHandleMark rnhm;
1318     patch_code(thread, load_mirror_patching_id);
1319   }
1320   // Back in JAVA, use no oops DON'T safepoint
1321 
1322   // Return true if calling code is deoptimized
1323 
1324   return caller_is_deopted();
1325 }
1326 
1327 int Runtime1::move_appendix_patching(JavaThread* thread) {
1328 //
1329 // NOTE: we are still in Java
1330 //
1331   Thread* THREAD = thread;
1332   debug_only(NoHandleMark nhm;)
1333   {
1334     // Enter VM mode
1335 
1336     ResetNoHandleMark rnhm;
1337     patch_code(thread, load_appendix_patching_id);
1338   }
1339   // Back in JAVA, use no oops DON'T safepoint
1340 
1341   // Return true if calling code is deoptimized
1342 
1343   return caller_is_deopted();
1344 }
1345 //
1346 // Entry point for compiled code. We want to patch a nmethod.
1347 // We don't do a normal VM transition here because we want to
1348 // know after the patching is complete and any safepoint(s) are taken
1349 // if the calling nmethod was deoptimized. We do this by calling a
1350 // helper method which does the normal VM transition and when it
1351 // completes we can check for deoptimization. This simplifies the
1352 // assembly code in the cpu directories.
1353 //
1354 
1355 int Runtime1::access_field_patching(JavaThread* thread) {
1356 //
1357 // NOTE: we are still in Java
1358 //
1359   Thread* THREAD = thread;
1360   debug_only(NoHandleMark nhm;)
1361   {
1362     // Enter VM mode
1363 
1364     ResetNoHandleMark rnhm;
1365     patch_code(thread, access_field_patching_id);
1366   }
1367   // Back in JAVA, use no oops DON'T safepoint
1368 
1369   // Return true if calling code is deoptimized
1370 
1371   return caller_is_deopted();
1372 JRT_END
1373 
1374 
1375 JRT_LEAF(void, Runtime1::trace_block_entry(jint block_id))
1376   // for now we just print out the block id
1377   tty->print("%d ", block_id);
1378 JRT_END
1379 
1380 
1381 JRT_LEAF(int, Runtime1::is_instance_of(oopDesc* mirror, oopDesc* obj))
1382   // had to return int instead of bool, otherwise there may be a mismatch
1383   // between the C calling convention and the Java one.
1384   // e.g., on x86, GCC may clear only %al when returning a bool false, but
1385   // JVM takes the whole %eax as the return value, which may misinterpret
1386   // the return value as a boolean true.
1387 
1388   assert(mirror != NULL, "should null-check on mirror before calling");
1389   Klass* k = java_lang_Class::as_Klass(mirror);
1390   return (k != NULL && obj != NULL && obj->is_a(k)) ? 1 : 0;
1391 JRT_END
1392 
1393 JRT_ENTRY(void, Runtime1::predicate_failed_trap(JavaThread* thread))
1394   ResourceMark rm;
1395 
1396   assert(!TieredCompilation, "incompatible with tiered compilation");
1397 
1398   RegisterMap reg_map(thread, false);
1399   frame runtime_frame = thread->last_frame();
1400   frame caller_frame = runtime_frame.sender(&reg_map);
1401 
1402   nmethod* nm = CodeCache::find_nmethod(caller_frame.pc());
1403   assert (nm != NULL, "no more nmethod?");
1404   nm->make_not_entrant();
1405 
1406   methodHandle m(nm->method());
1407   MethodData* mdo = m->method_data();
1408 
1409   if (mdo == NULL && !HAS_PENDING_EXCEPTION) {
1410     // Build an MDO.  Ignore errors like OutOfMemory;
1411     // that simply means we won't have an MDO to update.
1412     Method::build_interpreter_method_data(m, THREAD);
1413     if (HAS_PENDING_EXCEPTION) {
1414       assert((PENDING_EXCEPTION->is_a(SystemDictionary::OutOfMemoryError_klass())), "we expect only an OOM error here");
1415       CLEAR_PENDING_EXCEPTION;
1416     }
1417     mdo = m->method_data();
1418   }
1419 
1420   if (mdo != NULL) {
1421     mdo->inc_trap_count(Deoptimization::Reason_none);
1422   }
1423 
1424   if (TracePredicateFailedTraps) {
1425     stringStream ss1, ss2;
1426     vframeStream vfst(thread);
1427     methodHandle inlinee = methodHandle(vfst.method());
1428     inlinee->print_short_name(&ss1);
1429     m->print_short_name(&ss2);
1430     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()));
1431   }
1432 
1433 
1434   Deoptimization::deoptimize_frame(thread, caller_frame.id());
1435 
1436 JRT_END
1437 
1438 #ifndef PRODUCT
1439 void Runtime1::print_statistics() {
1440   tty->print_cr("C1 Runtime statistics:");
1441   tty->print_cr(" _resolve_invoke_virtual_cnt:     %d", SharedRuntime::_resolve_virtual_ctr);
1442   tty->print_cr(" _resolve_invoke_opt_virtual_cnt: %d", SharedRuntime::_resolve_opt_virtual_ctr);
1443   tty->print_cr(" _resolve_invoke_static_cnt:      %d", SharedRuntime::_resolve_static_ctr);
1444   tty->print_cr(" _handle_wrong_method_cnt:        %d", SharedRuntime::_wrong_method_ctr);
1445   tty->print_cr(" _ic_miss_cnt:                    %d", SharedRuntime::_ic_miss_ctr);
1446   tty->print_cr(" _generic_arraycopy_cnt:          %d", _generic_arraycopy_cnt);
1447   tty->print_cr(" _generic_arraycopystub_cnt:      %d", _generic_arraycopystub_cnt);
1448   tty->print_cr(" _byte_arraycopy_cnt:             %d", _byte_arraycopy_stub_cnt);
1449   tty->print_cr(" _short_arraycopy_cnt:            %d", _short_arraycopy_stub_cnt);
1450   tty->print_cr(" _int_arraycopy_cnt:              %d", _int_arraycopy_stub_cnt);
1451   tty->print_cr(" _long_arraycopy_cnt:             %d", _long_arraycopy_stub_cnt);
1452   tty->print_cr(" _oop_arraycopy_cnt:              %d", _oop_arraycopy_stub_cnt);
1453   tty->print_cr(" _arraycopy_slowcase_cnt:         %d", _arraycopy_slowcase_cnt);
1454   tty->print_cr(" _arraycopy_checkcast_cnt:        %d", _arraycopy_checkcast_cnt);
1455   tty->print_cr(" _arraycopy_checkcast_attempt_cnt:%d", _arraycopy_checkcast_attempt_cnt);
1456 
1457   tty->print_cr(" _new_type_array_slowcase_cnt:    %d", _new_type_array_slowcase_cnt);
1458   tty->print_cr(" _new_object_array_slowcase_cnt:  %d", _new_object_array_slowcase_cnt);
1459   tty->print_cr(" _new_instance_slowcase_cnt:      %d", _new_instance_slowcase_cnt);
1460   tty->print_cr(" _new_multi_array_slowcase_cnt:   %d", _new_multi_array_slowcase_cnt);
1461   tty->print_cr(" _monitorenter_slowcase_cnt:      %d", _monitorenter_slowcase_cnt);
1462   tty->print_cr(" _monitorexit_slowcase_cnt:       %d", _monitorexit_slowcase_cnt);
1463   tty->print_cr(" _patch_code_slowcase_cnt:        %d", _patch_code_slowcase_cnt);
1464 
1465   tty->print_cr(" _throw_range_check_exception_count:            %d:", _throw_range_check_exception_count);
1466   tty->print_cr(" _throw_index_exception_count:                  %d:", _throw_index_exception_count);
1467   tty->print_cr(" _throw_div0_exception_count:                   %d:", _throw_div0_exception_count);
1468   tty->print_cr(" _throw_null_pointer_exception_count:           %d:", _throw_null_pointer_exception_count);
1469   tty->print_cr(" _throw_class_cast_exception_count:             %d:", _throw_class_cast_exception_count);
1470   tty->print_cr(" _throw_incompatible_class_change_error_count:  %d:", _throw_incompatible_class_change_error_count);
1471   tty->print_cr(" _throw_array_store_exception_count:            %d:", _throw_array_store_exception_count);
1472   tty->print_cr(" _throw_count:                                  %d:", _throw_count);
1473 
1474   SharedRuntime::print_ic_miss_histogram();
1475   tty->cr();
1476 }
1477 #endif // PRODUCT