1 /*
   2  * Copyright (c) 1999, 2020, 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/javaClasses.inline.hpp"
  34 #include "classfile/systemDictionary.hpp"
  35 #include "classfile/vmSymbols.hpp"
  36 #include "code/codeBlob.hpp"
  37 #include "code/compiledIC.hpp"
  38 #include "code/pcDesc.hpp"
  39 #include "code/scopeDesc.hpp"
  40 #include "code/vtableStubs.hpp"
  41 #include "compiler/compilationPolicy.hpp"
  42 #include "compiler/disassembler.hpp"
  43 #include "gc/shared/barrierSet.hpp"
  44 #include "gc/shared/c1/barrierSetC1.hpp"
  45 #include "gc/shared/collectedHeap.hpp"
  46 #include "interpreter/bytecode.hpp"
  47 #include "interpreter/interpreter.hpp"
  48 #include "jfr/support/jfrIntrinsics.hpp"
  49 #include "logging/log.hpp"
  50 #include "memory/allocation.inline.hpp"
  51 #include "memory/oopFactory.hpp"
  52 #include "memory/resourceArea.hpp"
  53 #include "memory/universe.hpp"
  54 #include "oops/access.inline.hpp"
  55 #include "oops/objArrayOop.inline.hpp"
  56 #include "oops/objArrayKlass.hpp"
  57 #include "oops/oop.inline.hpp"
  58 #include "runtime/atomic.hpp"
  59 #include "runtime/biasedLocking.hpp"
  60 #include "runtime/fieldDescriptor.inline.hpp"
  61 #include "runtime/frame.inline.hpp"
  62 #include "runtime/handles.inline.hpp"
  63 #include "runtime/interfaceSupport.inline.hpp"
  64 #include "runtime/javaCalls.hpp"
  65 #include "runtime/sharedRuntime.hpp"
  66 #include "runtime/threadCritical.hpp"
  67 #include "runtime/vframe.inline.hpp"
  68 #include "runtime/vframeArray.hpp"
  69 #include "runtime/vm_version.hpp"
  70 #include "utilities/copy.hpp"
  71 #include "utilities/events.hpp"
  72 
  73 
  74 // Implementation of StubAssembler
  75 
  76 StubAssembler::StubAssembler(CodeBuffer* code, const char * name, int stub_id) : C1_MacroAssembler(code) {
  77   _name = name;
  78   _must_gc_arguments = false;
  79   _frame_size = no_frame_size;
  80   _num_rt_args = 0;
  81   _stub_id = stub_id;
  82 }
  83 
  84 
  85 void StubAssembler::set_info(const char* name, bool must_gc_arguments) {
  86   _name = name;
  87   _must_gc_arguments = must_gc_arguments;
  88 }
  89 
  90 
  91 void StubAssembler::set_frame_size(int size) {
  92   if (_frame_size == no_frame_size) {
  93     _frame_size = size;
  94   }
  95   assert(_frame_size == size, "can't change the frame size");
  96 }
  97 
  98 
  99 void StubAssembler::set_num_rt_args(int args) {
 100   if (_num_rt_args == 0) {
 101     _num_rt_args = args;
 102   }
 103   assert(_num_rt_args == args, "can't change the number of args");
 104 }
 105 
 106 // Implementation of Runtime1
 107 
 108 CodeBlob* Runtime1::_blobs[Runtime1::number_of_ids];
 109 const char *Runtime1::_blob_names[] = {
 110   RUNTIME1_STUBS(STUB_NAME, LAST_STUB_NAME)
 111 };
 112 
 113 #ifndef PRODUCT
 114 // statistics
 115 int Runtime1::_generic_arraycopy_cnt = 0;
 116 int Runtime1::_generic_arraycopystub_cnt = 0;
 117 int Runtime1::_arraycopy_slowcase_cnt = 0;
 118 int Runtime1::_arraycopy_checkcast_cnt = 0;
 119 int Runtime1::_arraycopy_checkcast_attempt_cnt = 0;
 120 int Runtime1::_new_type_array_slowcase_cnt = 0;
 121 int Runtime1::_new_object_array_slowcase_cnt = 0;
 122 int Runtime1::_new_instance_slowcase_cnt = 0;
 123 int Runtime1::_new_multi_array_slowcase_cnt = 0;
 124 int Runtime1::_monitorenter_slowcase_cnt = 0;
 125 int Runtime1::_monitorexit_slowcase_cnt = 0;
 126 int Runtime1::_patch_code_slowcase_cnt = 0;
 127 int Runtime1::_throw_range_check_exception_count = 0;
 128 int Runtime1::_throw_index_exception_count = 0;
 129 int Runtime1::_throw_div0_exception_count = 0;
 130 int Runtime1::_throw_null_pointer_exception_count = 0;
 131 int Runtime1::_throw_class_cast_exception_count = 0;
 132 int Runtime1::_throw_incompatible_class_change_error_count = 0;
 133 int Runtime1::_throw_array_store_exception_count = 0;
 134 int Runtime1::_throw_count = 0;
 135 
 136 static int _byte_arraycopy_stub_cnt = 0;
 137 static int _short_arraycopy_stub_cnt = 0;
 138 static int _int_arraycopy_stub_cnt = 0;
 139 static int _long_arraycopy_stub_cnt = 0;
 140 static int _oop_arraycopy_stub_cnt = 0;
 141 
 142 address Runtime1::arraycopy_count_address(BasicType type) {
 143   switch (type) {
 144   case T_BOOLEAN:
 145   case T_BYTE:   return (address)&_byte_arraycopy_stub_cnt;
 146   case T_CHAR:
 147   case T_SHORT:  return (address)&_short_arraycopy_stub_cnt;
 148   case T_FLOAT:
 149   case T_INT:    return (address)&_int_arraycopy_stub_cnt;
 150   case T_DOUBLE:
 151   case T_LONG:   return (address)&_long_arraycopy_stub_cnt;
 152   case T_ARRAY:
 153   case T_OBJECT: return (address)&_oop_arraycopy_stub_cnt;
 154   default:
 155     ShouldNotReachHere();
 156     return NULL;
 157   }
 158 }
 159 
 160 
 161 #endif
 162 
 163 // Simple helper to see if the caller of a runtime stub which
 164 // entered the VM has been deoptimized
 165 
 166 static bool caller_is_deopted() {
 167   JavaThread* thread = JavaThread::current();
 168   RegisterMap reg_map(thread, false);
 169   frame runtime_frame = thread->last_frame();
 170   frame caller_frame = runtime_frame.sender(&reg_map);
 171   assert(caller_frame.is_compiled_frame(), "must be compiled");
 172   return caller_frame.is_deoptimized_frame();
 173 }
 174 
 175 // Stress deoptimization
 176 static void deopt_caller() {
 177   if ( !caller_is_deopted()) {
 178     JavaThread* thread = JavaThread::current();
 179     RegisterMap reg_map(thread, false);
 180     frame runtime_frame = thread->last_frame();
 181     frame caller_frame = runtime_frame.sender(&reg_map);
 182     Deoptimization::deoptimize_frame(thread, caller_frame.id());
 183     assert(caller_is_deopted(), "Must be deoptimized");
 184   }
 185 }
 186 
 187 class StubIDStubAssemblerCodeGenClosure: public StubAssemblerCodeGenClosure {
 188  private:
 189   Runtime1::StubID _id;
 190  public:
 191   StubIDStubAssemblerCodeGenClosure(Runtime1::StubID id) : _id(id) {}
 192   virtual OopMapSet* generate_code(StubAssembler* sasm) {
 193     return Runtime1::generate_code_for(_id, sasm);
 194   }
 195 };
 196 
 197 CodeBlob* Runtime1::generate_blob(BufferBlob* buffer_blob, int stub_id, const char* name, bool expect_oop_map, StubAssemblerCodeGenClosure* cl) {
 198   ResourceMark rm;
 199   // create code buffer for code storage
 200   CodeBuffer code(buffer_blob);
 201 
 202   OopMapSet* oop_maps;
 203   int frame_size;
 204   bool must_gc_arguments;
 205 
 206   Compilation::setup_code_buffer(&code, 0);
 207 
 208   // create assembler for code generation
 209   StubAssembler* sasm = new StubAssembler(&code, name, stub_id);
 210   // generate code for runtime stub
 211   oop_maps = cl->generate_code(sasm);
 212   assert(oop_maps == NULL || sasm->frame_size() != no_frame_size,
 213          "if stub has an oop map it must have a valid frame size");
 214   assert(!expect_oop_map || oop_maps != NULL, "must have an oopmap");
 215 
 216   // align so printing shows nop's instead of random code at the end (SimpleStubs are aligned)
 217   sasm->align(BytesPerWord);
 218   // make sure all code is in code buffer
 219   sasm->flush();
 220 
 221   frame_size = sasm->frame_size();
 222   must_gc_arguments = sasm->must_gc_arguments();
 223   // create blob - distinguish a few special cases
 224   CodeBlob* blob = RuntimeStub::new_runtime_stub(name,
 225                                                  &code,
 226                                                  CodeOffsets::frame_never_safe,
 227                                                  frame_size,
 228                                                  oop_maps,
 229                                                  must_gc_arguments);
 230   assert(blob != NULL, "blob must exist");
 231   return blob;
 232 }
 233 
 234 void Runtime1::generate_blob_for(BufferBlob* buffer_blob, StubID id) {
 235   assert(0 <= id && id < number_of_ids, "illegal stub id");
 236   bool expect_oop_map = true;
 237 #ifdef ASSERT
 238   // Make sure that stubs that need oopmaps have them
 239   switch (id) {
 240     // These stubs don't need to have an oopmap
 241   case dtrace_object_alloc_id:
 242   case slow_subtype_check_id:
 243   case fpu2long_stub_id:
 244   case unwind_exception_id:
 245   case counter_overflow_id:
 246 #if defined(PPC32)
 247   case handle_exception_nofpu_id:  // Unused on sparc
 248 #endif
 249     expect_oop_map = false;
 250     break;
 251   default:
 252     break;
 253   }
 254 #endif
 255   StubIDStubAssemblerCodeGenClosure cl(id);
 256   CodeBlob* blob = generate_blob(buffer_blob, id, name_for(id), expect_oop_map, &cl);
 257   // install blob
 258   _blobs[id] = blob;
 259 }
 260 
 261 void Runtime1::initialize(BufferBlob* blob) {
 262   // platform-dependent initialization
 263   initialize_pd();
 264   // generate stubs
 265   for (int id = 0; id < number_of_ids; id++) generate_blob_for(blob, (StubID)id);
 266   // printing
 267 #ifndef PRODUCT
 268   if (PrintSimpleStubs) {
 269     ResourceMark rm;
 270     for (int id = 0; id < number_of_ids; id++) {
 271       _blobs[id]->print();
 272       if (_blobs[id]->oop_maps() != NULL) {
 273         _blobs[id]->oop_maps()->print();
 274       }
 275     }
 276   }
 277 #endif
 278   BarrierSetC1* bs = BarrierSet::barrier_set()->barrier_set_c1();
 279   bs->generate_c1_runtime_stubs(blob);
 280 }
 281 
 282 CodeBlob* Runtime1::blob_for(StubID id) {
 283   assert(0 <= id && id < number_of_ids, "illegal stub id");
 284   return _blobs[id];
 285 }
 286 
 287 
 288 const char* Runtime1::name_for(StubID id) {
 289   assert(0 <= id && id < number_of_ids, "illegal stub id");
 290   return _blob_names[id];
 291 }
 292 
 293 const char* Runtime1::name_for_address(address entry) {
 294   for (int id = 0; id < number_of_ids; id++) {
 295     if (entry == entry_for((StubID)id)) return name_for((StubID)id);
 296   }
 297 
 298   BarrierSetC1* bsc1 = BarrierSet::barrier_set()->barrier_set_c1();
 299   const char* name = bsc1->rtcall_name_for_address(entry);
 300   if (name != NULL) {
 301     return name;
 302   }
 303 
 304 #define FUNCTION_CASE(a, f) \
 305   if ((intptr_t)a == CAST_FROM_FN_PTR(intptr_t, f))  return #f
 306 
 307   FUNCTION_CASE(entry, os::javaTimeMillis);
 308   FUNCTION_CASE(entry, os::javaTimeNanos);
 309   FUNCTION_CASE(entry, SharedRuntime::OSR_migration_end);
 310   FUNCTION_CASE(entry, SharedRuntime::d2f);
 311   FUNCTION_CASE(entry, SharedRuntime::d2i);
 312   FUNCTION_CASE(entry, SharedRuntime::d2l);
 313   FUNCTION_CASE(entry, SharedRuntime::dcos);
 314   FUNCTION_CASE(entry, SharedRuntime::dexp);
 315   FUNCTION_CASE(entry, SharedRuntime::dlog);
 316   FUNCTION_CASE(entry, SharedRuntime::dlog10);
 317   FUNCTION_CASE(entry, SharedRuntime::dpow);
 318   FUNCTION_CASE(entry, SharedRuntime::drem);
 319   FUNCTION_CASE(entry, SharedRuntime::dsin);
 320   FUNCTION_CASE(entry, SharedRuntime::dtan);
 321   FUNCTION_CASE(entry, SharedRuntime::f2i);
 322   FUNCTION_CASE(entry, SharedRuntime::f2l);
 323   FUNCTION_CASE(entry, SharedRuntime::frem);
 324   FUNCTION_CASE(entry, SharedRuntime::l2d);
 325   FUNCTION_CASE(entry, SharedRuntime::l2f);
 326   FUNCTION_CASE(entry, SharedRuntime::ldiv);
 327   FUNCTION_CASE(entry, SharedRuntime::lmul);
 328   FUNCTION_CASE(entry, SharedRuntime::lrem);
 329   FUNCTION_CASE(entry, SharedRuntime::lrem);
 330   FUNCTION_CASE(entry, SharedRuntime::dtrace_method_entry);
 331   FUNCTION_CASE(entry, SharedRuntime::dtrace_method_exit);
 332   FUNCTION_CASE(entry, SharedRuntime::get_referenced_objects);
 333   FUNCTION_CASE(entry, is_instance_of);
 334   FUNCTION_CASE(entry, trace_block_entry);
 335 #ifdef JFR_HAVE_INTRINSICS
 336   FUNCTION_CASE(entry, JFR_TIME_FUNCTION);
 337 #endif
 338   FUNCTION_CASE(entry, StubRoutines::updateBytesCRC32());
 339   FUNCTION_CASE(entry, StubRoutines::updateBytesCRC32C());
 340   FUNCTION_CASE(entry, StubRoutines::vectorizedMismatch());
 341   FUNCTION_CASE(entry, StubRoutines::dexp());
 342   FUNCTION_CASE(entry, StubRoutines::dlog());
 343   FUNCTION_CASE(entry, StubRoutines::dlog10());
 344   FUNCTION_CASE(entry, StubRoutines::dpow());
 345   FUNCTION_CASE(entry, StubRoutines::dsin());
 346   FUNCTION_CASE(entry, StubRoutines::dcos());
 347   FUNCTION_CASE(entry, StubRoutines::dtan());
 348 
 349 #undef FUNCTION_CASE
 350 
 351   // Soft float adds more runtime names.
 352   return pd_name_for_address(entry);
 353 }
 354 
 355 
 356 JRT_ENTRY(void, Runtime1::new_instance(JavaThread* thread, Klass* klass))
 357   NOT_PRODUCT(_new_instance_slowcase_cnt++;)
 358 
 359   assert(klass->is_klass(), "not a class");
 360   Handle holder(THREAD, klass->klass_holder()); // keep the klass alive
 361   InstanceKlass* h = InstanceKlass::cast(klass);
 362   h->check_valid_for_instantiation(true, CHECK);
 363   // make sure klass is initialized
 364   h->initialize(CHECK);
 365   // allocate instance and return via TLS
 366   oop obj = h->allocate_instance(CHECK);
 367   thread->set_vm_result(obj);
 368 JRT_END
 369 
 370 
 371 JRT_ENTRY(void, Runtime1::new_type_array(JavaThread* thread, Klass* klass, jint length))
 372   NOT_PRODUCT(_new_type_array_slowcase_cnt++;)
 373   // Note: no handle for klass needed since they are not used
 374   //       anymore after new_typeArray() and no GC can happen before.
 375   //       (This may have to change if this code changes!)
 376   assert(klass->is_klass(), "not a class");
 377   BasicType elt_type = TypeArrayKlass::cast(klass)->element_type();
 378   oop obj = oopFactory::new_typeArray(elt_type, length, CHECK);
 379   thread->set_vm_result(obj);
 380   // This is pretty rare but this runtime patch is stressful to deoptimization
 381   // if we deoptimize here so force a deopt to stress the path.
 382   if (DeoptimizeALot) {
 383     deopt_caller();
 384   }
 385 
 386 JRT_END
 387 
 388 
 389 JRT_ENTRY(void, Runtime1::new_object_array(JavaThread* thread, Klass* array_klass, jint length))
 390   NOT_PRODUCT(_new_object_array_slowcase_cnt++;)
 391 
 392   // Note: no handle for klass needed since they are not used
 393   //       anymore after new_objArray() and no GC can happen before.
 394   //       (This may have to change if this code changes!)
 395   assert(array_klass->is_klass(), "not a class");
 396   Handle holder(THREAD, array_klass->klass_holder()); // keep the klass alive
 397   Klass* elem_klass = ObjArrayKlass::cast(array_klass)->element_klass();
 398   objArrayOop obj = oopFactory::new_objArray(elem_klass, length, CHECK);
 399   thread->set_vm_result(obj);
 400   // This is pretty rare but this runtime patch is stressful to deoptimization
 401   // if we deoptimize here so force a deopt to stress the path.
 402   if (DeoptimizeALot) {
 403     deopt_caller();
 404   }
 405 JRT_END
 406 
 407 
 408 JRT_ENTRY(void, Runtime1::new_multi_array(JavaThread* thread, Klass* klass, int rank, jint* dims))
 409   NOT_PRODUCT(_new_multi_array_slowcase_cnt++;)
 410 
 411   assert(klass->is_klass(), "not a class");
 412   assert(rank >= 1, "rank must be nonzero");
 413   Handle holder(THREAD, klass->klass_holder()); // keep the klass alive
 414   oop obj = ArrayKlass::cast(klass)->multi_allocate(rank, dims, CHECK);
 415   thread->set_vm_result(obj);
 416 JRT_END
 417 
 418 
 419 JRT_ENTRY(void, Runtime1::unimplemented_entry(JavaThread* thread, StubID id))
 420   tty->print_cr("Runtime1::entry_for(%d) returned unimplemented entry point", id);
 421 JRT_END
 422 
 423 
 424 JRT_ENTRY(void, Runtime1::throw_array_store_exception(JavaThread* thread, oopDesc* obj))
 425   ResourceMark rm(thread);
 426   const char* klass_name = obj->klass()->external_name();
 427   SharedRuntime::throw_and_post_jvmti_exception(thread, vmSymbols::java_lang_ArrayStoreException(), klass_name);
 428 JRT_END
 429 
 430 
 431 // counter_overflow() is called from within C1-compiled methods. The enclosing method is the method
 432 // associated with the top activation record. The inlinee (that is possibly included in the enclosing
 433 // method) method is passed as an argument. In order to do that it is embedded in the code as
 434 // a constant.
 435 static nmethod* counter_overflow_helper(JavaThread* THREAD, int branch_bci, Method* m) {
 436   nmethod* osr_nm = NULL;
 437   methodHandle method(THREAD, m);
 438 
 439   RegisterMap map(THREAD, false);
 440   frame fr =  THREAD->last_frame().sender(&map);
 441   nmethod* nm = (nmethod*) fr.cb();
 442   assert(nm!= NULL && nm->is_nmethod(), "Sanity check");
 443   methodHandle enclosing_method(THREAD, nm->method());
 444 
 445   CompLevel level = (CompLevel)nm->comp_level();
 446   int bci = InvocationEntryBci;
 447   if (branch_bci != InvocationEntryBci) {
 448     // Compute destination bci
 449     address pc = method()->code_base() + branch_bci;
 450     Bytecodes::Code branch = Bytecodes::code_at(method(), pc);
 451     int offset = 0;
 452     switch (branch) {
 453       case Bytecodes::_if_icmplt: case Bytecodes::_iflt:
 454       case Bytecodes::_if_icmpgt: case Bytecodes::_ifgt:
 455       case Bytecodes::_if_icmple: case Bytecodes::_ifle:
 456       case Bytecodes::_if_icmpge: case Bytecodes::_ifge:
 457       case Bytecodes::_if_icmpeq: case Bytecodes::_if_acmpeq: case Bytecodes::_ifeq:
 458       case Bytecodes::_if_icmpne: case Bytecodes::_if_acmpne: case Bytecodes::_ifne:
 459       case Bytecodes::_ifnull: case Bytecodes::_ifnonnull: case Bytecodes::_goto:
 460         offset = (int16_t)Bytes::get_Java_u2(pc + 1);
 461         break;
 462       case Bytecodes::_goto_w:
 463         offset = Bytes::get_Java_u4(pc + 1);
 464         break;
 465       default: ;
 466     }
 467     bci = branch_bci + offset;
 468   }
 469   assert(!HAS_PENDING_EXCEPTION, "Should not have any exceptions pending");
 470   osr_nm = CompilationPolicy::policy()->event(enclosing_method, method, branch_bci, bci, level, nm, THREAD);
 471   assert(!HAS_PENDING_EXCEPTION, "Event handler should not throw any exceptions");
 472   return osr_nm;
 473 }
 474 
 475 JRT_BLOCK_ENTRY(address, Runtime1::counter_overflow(JavaThread* thread, int bci, Method* method))
 476   nmethod* osr_nm;
 477   JRT_BLOCK
 478     osr_nm = counter_overflow_helper(thread, bci, method);
 479     if (osr_nm != NULL) {
 480       RegisterMap map(thread, false);
 481       frame fr =  thread->last_frame().sender(&map);
 482       Deoptimization::deoptimize_frame(thread, fr.id());
 483     }
 484   JRT_BLOCK_END
 485   return NULL;
 486 JRT_END
 487 
 488 extern void vm_exit(int code);
 489 
 490 // Enter this method from compiled code handler below. This is where we transition
 491 // to VM mode. This is done as a helper routine so that the method called directly
 492 // from compiled code does not have to transition to VM. This allows the entry
 493 // method to see if the nmethod that we have just looked up a handler for has
 494 // been deoptimized while we were in the vm. This simplifies the assembly code
 495 // cpu directories.
 496 //
 497 // We are entering here from exception stub (via the entry method below)
 498 // If there is a compiled exception handler in this method, we will continue there;
 499 // otherwise we will unwind the stack and continue at the caller of top frame method
 500 // Note: we enter in Java using a special JRT wrapper. This wrapper allows us to
 501 // control the area where we can allow a safepoint. After we exit the safepoint area we can
 502 // check to see if the handler we are going to return is now in a nmethod that has
 503 // been deoptimized. If that is the case we return the deopt blob
 504 // unpack_with_exception entry instead. This makes life for the exception blob easier
 505 // because making that same check and diverting is painful from assembly language.
 506 JRT_ENTRY_NO_ASYNC(static address, exception_handler_for_pc_helper(JavaThread* thread, oopDesc* ex, address pc, nmethod*& nm))
 507   // Reset method handle flag.
 508   thread->set_is_method_handle_return(false);
 509 
 510   Handle exception(thread, ex);
 511   nm = CodeCache::find_nmethod(pc);
 512   assert(nm != NULL, "this is not an nmethod");
 513   // Adjust the pc as needed/
 514   if (nm->is_deopt_pc(pc)) {
 515     RegisterMap map(thread, false);
 516     frame exception_frame = thread->last_frame().sender(&map);
 517     // if the frame isn't deopted then pc must not correspond to the caller of last_frame
 518     assert(exception_frame.is_deoptimized_frame(), "must be deopted");
 519     pc = exception_frame.pc();
 520   }
 521 #ifdef ASSERT
 522   assert(exception.not_null(), "NULL exceptions should be handled by throw_exception");
 523   // Check that exception is a subclass of Throwable, otherwise we have a VerifyError
 524   if (!(exception->is_a(SystemDictionary::Throwable_klass()))) {
 525     if (ExitVMOnVerifyError) vm_exit(-1);
 526     ShouldNotReachHere();
 527   }
 528 #endif
 529 
 530   // Check the stack guard pages and reenable them if necessary and there is
 531   // enough space on the stack to do so.  Use fast exceptions only if the guard
 532   // pages are enabled.
 533   bool guard_pages_enabled = thread->stack_guards_enabled();
 534   if (!guard_pages_enabled) guard_pages_enabled = thread->reguard_stack();
 535 
 536   if (JvmtiExport::can_post_on_exceptions()) {
 537     // To ensure correct notification of exception catches and throws
 538     // we have to deoptimize here.  If we attempted to notify the
 539     // catches and throws during this exception lookup it's possible
 540     // we could deoptimize on the way out of the VM and end back in
 541     // the interpreter at the throw site.  This would result in double
 542     // notifications since the interpreter would also notify about
 543     // these same catches and throws as it unwound the frame.
 544 
 545     RegisterMap reg_map(thread);
 546     frame stub_frame = thread->last_frame();
 547     frame caller_frame = stub_frame.sender(&reg_map);
 548 
 549     // We don't really want to deoptimize the nmethod itself since we
 550     // can actually continue in the exception handler ourselves but I
 551     // don't see an easy way to have the desired effect.
 552     Deoptimization::deoptimize_frame(thread, caller_frame.id());
 553     assert(caller_is_deopted(), "Must be deoptimized");
 554 
 555     return SharedRuntime::deopt_blob()->unpack_with_exception_in_tls();
 556   }
 557 
 558   // ExceptionCache is used only for exceptions at call sites and not for implicit exceptions
 559   if (guard_pages_enabled) {
 560     address fast_continuation = nm->handler_for_exception_and_pc(exception, pc);
 561     if (fast_continuation != NULL) {
 562       // Set flag if return address is a method handle call site.
 563       thread->set_is_method_handle_return(nm->is_method_handle_return(pc));
 564       return fast_continuation;
 565     }
 566   }
 567 
 568   // If the stack guard pages are enabled, check whether there is a handler in
 569   // the current method.  Otherwise (guard pages disabled), force an unwind and
 570   // skip the exception cache update (i.e., just leave continuation==NULL).
 571   address continuation = NULL;
 572   if (guard_pages_enabled) {
 573 
 574     // New exception handling mechanism can support inlined methods
 575     // with exception handlers since the mappings are from PC to PC
 576 
 577     // debugging support
 578     // tracing
 579     if (log_is_enabled(Info, exceptions)) {
 580       ResourceMark rm;
 581       stringStream tempst;
 582       assert(nm->method() != NULL, "Unexpected NULL method()");
 583       tempst.print("compiled method <%s>\n"
 584                    " at PC" INTPTR_FORMAT " for thread " INTPTR_FORMAT,
 585                    nm->method()->print_value_string(), p2i(pc), p2i(thread));
 586       Exceptions::log_exception(exception, tempst.as_string());
 587     }
 588     // for AbortVMOnException flag
 589     Exceptions::debug_check_abort(exception);
 590 
 591     // Clear out the exception oop and pc since looking up an
 592     // exception handler can cause class loading, which might throw an
 593     // exception and those fields are expected to be clear during
 594     // normal bytecode execution.
 595     thread->clear_exception_oop_and_pc();
 596 
 597     bool recursive_exception = false;
 598     continuation = SharedRuntime::compute_compiled_exc_handler(nm, pc, exception, false, false, recursive_exception);
 599     // If an exception was thrown during exception dispatch, the exception oop may have changed
 600     thread->set_exception_oop(exception());
 601     thread->set_exception_pc(pc);
 602 
 603     // the exception cache is used only by non-implicit exceptions
 604     // Update the exception cache only when there didn't happen
 605     // another exception during the computation of the compiled
 606     // exception handler. Checking for exception oop equality is not
 607     // sufficient because some exceptions are pre-allocated and reused.
 608     if (continuation != NULL && !recursive_exception) {
 609       nm->add_handler_for_exception_and_pc(exception, pc, continuation);
 610     }
 611   }
 612 
 613   thread->set_vm_result(exception());
 614   // Set flag if return address is a method handle call site.
 615   thread->set_is_method_handle_return(nm->is_method_handle_return(pc));
 616 
 617   if (log_is_enabled(Info, exceptions)) {
 618     ResourceMark rm;
 619     log_info(exceptions)("Thread " PTR_FORMAT " continuing at PC " PTR_FORMAT
 620                          " for exception thrown at PC " PTR_FORMAT,
 621                          p2i(thread), p2i(continuation), p2i(pc));
 622   }
 623 
 624   return continuation;
 625 JRT_END
 626 
 627 // Enter this method from compiled code only if there is a Java exception handler
 628 // in the method handling the exception.
 629 // We are entering here from exception stub. We don't do a normal VM transition here.
 630 // We do it in a helper. This is so we can check to see if the nmethod we have just
 631 // searched for an exception handler has been deoptimized in the meantime.
 632 address Runtime1::exception_handler_for_pc(JavaThread* thread) {
 633   oop exception = thread->exception_oop();
 634   address pc = thread->exception_pc();
 635   // Still in Java mode
 636   DEBUG_ONLY(ResetNoHandleMark rnhm);
 637   nmethod* nm = NULL;
 638   address continuation = NULL;
 639   {
 640     // Enter VM mode by calling the helper
 641     ResetNoHandleMark rnhm;
 642     continuation = exception_handler_for_pc_helper(thread, exception, pc, nm);
 643   }
 644   // Back in JAVA, use no oops DON'T safepoint
 645 
 646   // Now check to see if the nmethod we were called from is now deoptimized.
 647   // If so we must return to the deopt blob and deoptimize the nmethod
 648   if (nm != NULL && caller_is_deopted()) {
 649     continuation = SharedRuntime::deopt_blob()->unpack_with_exception_in_tls();
 650   }
 651 
 652   assert(continuation != NULL, "no handler found");
 653   return continuation;
 654 }
 655 
 656 
 657 JRT_ENTRY(void, Runtime1::throw_range_check_exception(JavaThread* thread, int index, arrayOopDesc* a))
 658   NOT_PRODUCT(_throw_range_check_exception_count++;)
 659   const int len = 35;
 660   assert(len < strlen("Index %d out of bounds for length %d"), "Must allocate more space for message.");
 661   char message[2 * jintAsStringSize + len];
 662   sprintf(message, "Index %d out of bounds for length %d", index, a->length());
 663   SharedRuntime::throw_and_post_jvmti_exception(thread, vmSymbols::java_lang_ArrayIndexOutOfBoundsException(), message);
 664 JRT_END
 665 
 666 
 667 JRT_ENTRY(void, Runtime1::throw_index_exception(JavaThread* thread, int index))
 668   NOT_PRODUCT(_throw_index_exception_count++;)
 669   char message[16];
 670   sprintf(message, "%d", index);
 671   SharedRuntime::throw_and_post_jvmti_exception(thread, vmSymbols::java_lang_IndexOutOfBoundsException(), message);
 672 JRT_END
 673 
 674 
 675 JRT_ENTRY(void, Runtime1::throw_div0_exception(JavaThread* thread))
 676   NOT_PRODUCT(_throw_div0_exception_count++;)
 677   SharedRuntime::throw_and_post_jvmti_exception(thread, vmSymbols::java_lang_ArithmeticException(), "/ by zero");
 678 JRT_END
 679 
 680 
 681 JRT_ENTRY(void, Runtime1::throw_null_pointer_exception(JavaThread* thread))
 682   NOT_PRODUCT(_throw_null_pointer_exception_count++;)
 683   SharedRuntime::throw_and_post_jvmti_exception(thread, vmSymbols::java_lang_NullPointerException());
 684 JRT_END
 685 
 686 
 687 JRT_ENTRY(void, Runtime1::throw_class_cast_exception(JavaThread* thread, oopDesc* object))
 688   NOT_PRODUCT(_throw_class_cast_exception_count++;)
 689   ResourceMark rm(thread);
 690   char* message = SharedRuntime::generate_class_cast_message(
 691     thread, object->klass());
 692   SharedRuntime::throw_and_post_jvmti_exception(
 693     thread, vmSymbols::java_lang_ClassCastException(), message);
 694 JRT_END
 695 
 696 
 697 JRT_ENTRY(void, Runtime1::throw_incompatible_class_change_error(JavaThread* thread))
 698   NOT_PRODUCT(_throw_incompatible_class_change_error_count++;)
 699   ResourceMark rm(thread);
 700   SharedRuntime::throw_and_post_jvmti_exception(thread, vmSymbols::java_lang_IncompatibleClassChangeError());
 701 JRT_END
 702 
 703 
 704 JRT_BLOCK_ENTRY(void, Runtime1::monitorenter(JavaThread* thread, oopDesc* obj, BasicObjectLock* lock))
 705   NOT_PRODUCT(_monitorenter_slowcase_cnt++;)
 706   if (!UseFastLocking) {
 707     lock->set_obj(obj);
 708   }
 709   assert(obj == lock->obj(), "must match");
 710   SharedRuntime::monitor_enter_helper(obj, lock->lock(), thread);
 711 JRT_END
 712 
 713 
 714 JRT_LEAF(void, Runtime1::monitorexit(JavaThread* thread, BasicObjectLock* lock))
 715   NOT_PRODUCT(_monitorexit_slowcase_cnt++;)
 716   assert(thread->last_Java_sp(), "last_Java_sp must be set");
 717   oop obj = lock->obj();
 718   assert(oopDesc::is_oop(obj), "must be NULL or an object");
 719   SharedRuntime::monitor_exit_helper(obj, lock->lock(), thread);
 720 JRT_END
 721 
 722 // Cf. OptoRuntime::deoptimize_caller_frame
 723 JRT_ENTRY(void, Runtime1::deoptimize(JavaThread* thread, jint trap_request))
 724   // Called from within the owner thread, so no need for safepoint
 725   RegisterMap reg_map(thread, false);
 726   frame stub_frame = thread->last_frame();
 727   assert(stub_frame.is_runtime_frame(), "Sanity check");
 728   frame caller_frame = stub_frame.sender(&reg_map);
 729   nmethod* nm = caller_frame.cb()->as_nmethod_or_null();
 730   assert(nm != NULL, "Sanity check");
 731   methodHandle method(thread, nm->method());
 732   assert(nm == CodeCache::find_nmethod(caller_frame.pc()), "Should be the same");
 733   Deoptimization::DeoptAction action = Deoptimization::trap_request_action(trap_request);
 734   Deoptimization::DeoptReason reason = Deoptimization::trap_request_reason(trap_request);
 735 
 736   if (action == Deoptimization::Action_make_not_entrant) {
 737     if (nm->make_not_entrant()) {
 738       if (reason == Deoptimization::Reason_tenured) {
 739         MethodData* trap_mdo = Deoptimization::get_method_data(thread, method, true /*create_if_missing*/);
 740         if (trap_mdo != NULL) {
 741           trap_mdo->inc_tenure_traps();
 742         }
 743       }
 744     }
 745   }
 746 
 747   // Deoptimize the caller frame.
 748   Deoptimization::deoptimize_frame(thread, caller_frame.id());
 749   // Return to the now deoptimized frame.
 750 JRT_END
 751 
 752 
 753 #ifndef DEOPTIMIZE_WHEN_PATCHING
 754 
 755 static Klass* resolve_field_return_klass(const methodHandle& caller, int bci, TRAPS) {
 756   Bytecode_field field_access(caller, bci);
 757   // This can be static or non-static field access
 758   Bytecodes::Code code       = field_access.code();
 759 
 760   // We must load class, initialize class and resolve the field
 761   fieldDescriptor result; // initialize class if needed
 762   constantPoolHandle constants(THREAD, caller->constants());
 763   LinkResolver::resolve_field_access(result, constants, field_access.index(), caller, Bytecodes::java_code(code), CHECK_NULL);
 764   return result.field_holder();
 765 }
 766 
 767 
 768 //
 769 // This routine patches sites where a class wasn't loaded or
 770 // initialized at the time the code was generated.  It handles
 771 // references to classes, fields and forcing of initialization.  Most
 772 // of the cases are straightforward and involving simply forcing
 773 // resolution of a class, rewriting the instruction stream with the
 774 // needed constant and replacing the call in this function with the
 775 // patched code.  The case for static field is more complicated since
 776 // the thread which is in the process of initializing a class can
 777 // access it's static fields but other threads can't so the code
 778 // either has to deoptimize when this case is detected or execute a
 779 // check that the current thread is the initializing thread.  The
 780 // current
 781 //
 782 // Patches basically look like this:
 783 //
 784 //
 785 // patch_site: jmp patch stub     ;; will be patched
 786 // continue:   ...
 787 //             ...
 788 //             ...
 789 //             ...
 790 //
 791 // They have a stub which looks like this:
 792 //
 793 //             ;; patch body
 794 //             movl <const>, reg           (for class constants)
 795 //        <or> movl [reg1 + <const>], reg  (for field offsets)
 796 //        <or> movl reg, [reg1 + <const>]  (for field offsets)
 797 //             <being_init offset> <bytes to copy> <bytes to skip>
 798 // patch_stub: call Runtime1::patch_code (through a runtime stub)
 799 //             jmp patch_site
 800 //
 801 //
 802 // A normal patch is done by rewriting the patch body, usually a move,
 803 // and then copying it into place over top of the jmp instruction
 804 // being careful to flush caches and doing it in an MP-safe way.  The
 805 // constants following the patch body are used to find various pieces
 806 // of the patch relative to the call site for Runtime1::patch_code.
 807 // The case for getstatic and putstatic is more complicated because
 808 // getstatic and putstatic have special semantics when executing while
 809 // the class is being initialized.  getstatic/putstatic on a class
 810 // which is being_initialized may be executed by the initializing
 811 // thread but other threads have to block when they execute it.  This
 812 // is accomplished in compiled code by executing a test of the current
 813 // thread against the initializing thread of the class.  It's emitted
 814 // as boilerplate in their stub which allows the patched code to be
 815 // executed before it's copied back into the main body of the nmethod.
 816 //
 817 // being_init: get_thread(<tmp reg>
 818 //             cmpl [reg1 + <init_thread_offset>], <tmp reg>
 819 //             jne patch_stub
 820 //             movl [reg1 + <const>], reg  (for field offsets)  <or>
 821 //             movl reg, [reg1 + <const>]  (for field offsets)
 822 //             jmp continue
 823 //             <being_init offset> <bytes to copy> <bytes to skip>
 824 // patch_stub: jmp Runtim1::patch_code (through a runtime stub)
 825 //             jmp patch_site
 826 //
 827 // If the class is being initialized the patch body is rewritten and
 828 // the patch site is rewritten to jump to being_init, instead of
 829 // patch_stub.  Whenever this code is executed it checks the current
 830 // thread against the intializing thread so other threads will enter
 831 // the runtime and end up blocked waiting the class to finish
 832 // initializing inside the calls to resolve_field below.  The
 833 // initializing class will continue on it's way.  Once the class is
 834 // fully_initialized, the intializing_thread of the class becomes
 835 // NULL, so the next thread to execute this code will fail the test,
 836 // call into patch_code and complete the patching process by copying
 837 // the patch body back into the main part of the nmethod and resume
 838 // executing.
 839 
 840 // NB:
 841 //
 842 // Patchable instruction sequences inherently exhibit race conditions,
 843 // where thread A is patching an instruction at the same time thread B
 844 // is executing it.  The algorithms we use ensure that any observation
 845 // that B can make on any intermediate states during A's patching will
 846 // always end up with a correct outcome.  This is easiest if there are
 847 // few or no intermediate states.  (Some inline caches have two
 848 // related instructions that must be patched in tandem.  For those,
 849 // intermediate states seem to be unavoidable, but we will get the
 850 // right answer from all possible observation orders.)
 851 //
 852 // When patching the entry instruction at the head of a method, or a
 853 // linkable call instruction inside of a method, we try very hard to
 854 // use a patch sequence which executes as a single memory transaction.
 855 // This means, in practice, that when thread A patches an instruction,
 856 // it should patch a 32-bit or 64-bit word that somehow overlaps the
 857 // instruction or is contained in it.  We believe that memory hardware
 858 // will never break up such a word write, if it is naturally aligned
 859 // for the word being written.  We also know that some CPUs work very
 860 // hard to create atomic updates even of naturally unaligned words,
 861 // but we don't want to bet the farm on this always working.
 862 //
 863 // Therefore, if there is any chance of a race condition, we try to
 864 // patch only naturally aligned words, as single, full-word writes.
 865 
 866 JRT_ENTRY(void, Runtime1::patch_code(JavaThread* thread, Runtime1::StubID stub_id ))
 867   NOT_PRODUCT(_patch_code_slowcase_cnt++;)
 868 
 869   ResourceMark rm(thread);
 870   RegisterMap reg_map(thread, false);
 871   frame runtime_frame = thread->last_frame();
 872   frame caller_frame = runtime_frame.sender(&reg_map);
 873 
 874   // last java frame on stack
 875   vframeStream vfst(thread, true);
 876   assert(!vfst.at_end(), "Java frame must exist");
 877 
 878   methodHandle caller_method(THREAD, vfst.method());
 879   // Note that caller_method->code() may not be same as caller_code because of OSR's
 880   // Note also that in the presence of inlining it is not guaranteed
 881   // that caller_method() == caller_code->method()
 882 
 883   int bci = vfst.bci();
 884   Bytecodes::Code code = caller_method()->java_code_at(bci);
 885 
 886   // this is used by assertions in the access_field_patching_id
 887   BasicType patch_field_type = T_ILLEGAL;
 888   bool deoptimize_for_volatile = false;
 889   bool deoptimize_for_atomic = false;
 890   int patch_field_offset = -1;
 891   Klass* init_klass = NULL; // klass needed by load_klass_patching code
 892   Klass* load_klass = NULL; // klass needed by load_klass_patching code
 893   Handle mirror(THREAD, NULL);                    // oop needed by load_mirror_patching code
 894   Handle appendix(THREAD, NULL);                  // oop needed by appendix_patching code
 895   bool load_klass_or_mirror_patch_id =
 896     (stub_id == Runtime1::load_klass_patching_id || stub_id == Runtime1::load_mirror_patching_id);
 897 
 898   if (stub_id == Runtime1::access_field_patching_id) {
 899 
 900     Bytecode_field field_access(caller_method, bci);
 901     fieldDescriptor result; // initialize class if needed
 902     Bytecodes::Code code = field_access.code();
 903     constantPoolHandle constants(THREAD, caller_method->constants());
 904     LinkResolver::resolve_field_access(result, constants, field_access.index(), caller_method, Bytecodes::java_code(code), CHECK);
 905     patch_field_offset = result.offset();
 906 
 907     // If we're patching a field which is volatile then at compile it
 908     // must not have been know to be volatile, so the generated code
 909     // isn't correct for a volatile reference.  The nmethod has to be
 910     // deoptimized so that the code can be regenerated correctly.
 911     // This check is only needed for access_field_patching since this
 912     // is the path for patching field offsets.  load_klass is only
 913     // used for patching references to oops which don't need special
 914     // handling in the volatile case.
 915 
 916     deoptimize_for_volatile = result.access_flags().is_volatile();
 917 
 918     // If we are patching a field which should be atomic, then
 919     // the generated code is not correct either, force deoptimizing.
 920     // We need to only cover T_LONG and T_DOUBLE fields, as we can
 921     // break access atomicity only for them.
 922 
 923     // Strictly speaking, the deoptimization on 64-bit platforms
 924     // is unnecessary, and T_LONG stores on 32-bit platforms need
 925     // to be handled by special patching code when AlwaysAtomicAccesses
 926     // becomes product feature. At this point, we are still going
 927     // for the deoptimization for consistency against volatile
 928     // accesses.
 929 
 930     patch_field_type = result.field_type();
 931     deoptimize_for_atomic = (AlwaysAtomicAccesses && (patch_field_type == T_DOUBLE || patch_field_type == T_LONG));
 932 
 933   } else if (load_klass_or_mirror_patch_id) {
 934     Klass* k = NULL;
 935     switch (code) {
 936       case Bytecodes::_putstatic:
 937       case Bytecodes::_getstatic:
 938         { Klass* klass = resolve_field_return_klass(caller_method, bci, CHECK);
 939           init_klass = klass;
 940           mirror = Handle(THREAD, klass->java_mirror());
 941         }
 942         break;
 943       case Bytecodes::_new:
 944         { Bytecode_new bnew(caller_method(), caller_method->bcp_from(bci));
 945           k = caller_method->constants()->klass_at(bnew.index(), CHECK);
 946         }
 947         break;
 948       case Bytecodes::_multianewarray:
 949         { Bytecode_multianewarray mna(caller_method(), caller_method->bcp_from(bci));
 950           k = caller_method->constants()->klass_at(mna.index(), CHECK);
 951         }
 952         break;
 953       case Bytecodes::_instanceof:
 954         { Bytecode_instanceof io(caller_method(), caller_method->bcp_from(bci));
 955           k = caller_method->constants()->klass_at(io.index(), CHECK);
 956         }
 957         break;
 958       case Bytecodes::_checkcast:
 959         { Bytecode_checkcast cc(caller_method(), caller_method->bcp_from(bci));
 960           k = caller_method->constants()->klass_at(cc.index(), CHECK);
 961         }
 962         break;
 963       case Bytecodes::_anewarray:
 964         { Bytecode_anewarray anew(caller_method(), caller_method->bcp_from(bci));
 965           Klass* ek = caller_method->constants()->klass_at(anew.index(), CHECK);
 966           k = ek->array_klass(CHECK);
 967         }
 968         break;
 969       case Bytecodes::_ldc:
 970       case Bytecodes::_ldc_w:
 971         {
 972           Bytecode_loadconstant cc(caller_method, bci);
 973           oop m = cc.resolve_constant(CHECK);
 974           mirror = Handle(THREAD, m);
 975         }
 976         break;
 977       default: fatal("unexpected bytecode for load_klass_or_mirror_patch_id");
 978     }
 979     load_klass = k;
 980   } else if (stub_id == load_appendix_patching_id) {
 981     Bytecode_invoke bytecode(caller_method, bci);
 982     Bytecodes::Code bc = bytecode.invoke_code();
 983 
 984     CallInfo info;
 985     constantPoolHandle pool(thread, caller_method->constants());
 986     int index = bytecode.index();
 987     LinkResolver::resolve_invoke(info, Handle(), pool, index, bc, CHECK);
 988     switch (bc) {
 989       case Bytecodes::_invokehandle: {
 990         int cache_index = ConstantPool::decode_cpcache_index(index, true);
 991         assert(cache_index >= 0 && cache_index < pool->cache()->length(), "unexpected cache index");
 992         ConstantPoolCacheEntry* cpce = pool->cache()->entry_at(cache_index);
 993         cpce->set_method_handle(pool, info);
 994         appendix = Handle(THREAD, cpce->appendix_if_resolved(pool)); // just in case somebody already resolved the entry
 995         break;
 996       }
 997       case Bytecodes::_invokedynamic: {
 998         ConstantPoolCacheEntry* cpce = pool->invokedynamic_cp_cache_entry_at(index);
 999         cpce->set_dynamic_call(pool, info);
1000         appendix = Handle(THREAD, cpce->appendix_if_resolved(pool)); // just in case somebody already resolved the entry
1001         break;
1002       }
1003       default: fatal("unexpected bytecode for load_appendix_patching_id");
1004     }
1005   } else {
1006     ShouldNotReachHere();
1007   }
1008 
1009   if (deoptimize_for_volatile || deoptimize_for_atomic) {
1010     // At compile time we assumed the field wasn't volatile/atomic but after
1011     // loading it turns out it was volatile/atomic so we have to throw the
1012     // compiled code out and let it be regenerated.
1013     if (TracePatching) {
1014       if (deoptimize_for_volatile) {
1015         tty->print_cr("Deoptimizing for patching volatile field reference");
1016       }
1017       if (deoptimize_for_atomic) {
1018         tty->print_cr("Deoptimizing for patching atomic field reference");
1019       }
1020     }
1021 
1022     // It's possible the nmethod was invalidated in the last
1023     // safepoint, but if it's still alive then make it not_entrant.
1024     nmethod* nm = CodeCache::find_nmethod(caller_frame.pc());
1025     if (nm != NULL) {
1026       nm->make_not_entrant();
1027     }
1028 
1029     Deoptimization::deoptimize_frame(thread, caller_frame.id());
1030 
1031     // Return to the now deoptimized frame.
1032   }
1033 
1034   // Now copy code back
1035 
1036   {
1037     MutexLocker ml_patch (THREAD, Patching_lock, Mutex::_no_safepoint_check_flag);
1038     //
1039     // Deoptimization may have happened while we waited for the lock.
1040     // In that case we don't bother to do any patching we just return
1041     // and let the deopt happen
1042     if (!caller_is_deopted()) {
1043       NativeGeneralJump* jump = nativeGeneralJump_at(caller_frame.pc());
1044       address instr_pc = jump->jump_destination();
1045       NativeInstruction* ni = nativeInstruction_at(instr_pc);
1046       if (ni->is_jump() ) {
1047         // the jump has not been patched yet
1048         // The jump destination is slow case and therefore not part of the stubs
1049         // (stubs are only for StaticCalls)
1050 
1051         // format of buffer
1052         //    ....
1053         //    instr byte 0     <-- copy_buff
1054         //    instr byte 1
1055         //    ..
1056         //    instr byte n-1
1057         //      n
1058         //    ....             <-- call destination
1059 
1060         address stub_location = caller_frame.pc() + PatchingStub::patch_info_offset();
1061         unsigned char* byte_count = (unsigned char*) (stub_location - 1);
1062         unsigned char* byte_skip = (unsigned char*) (stub_location - 2);
1063         unsigned char* being_initialized_entry_offset = (unsigned char*) (stub_location - 3);
1064         address copy_buff = stub_location - *byte_skip - *byte_count;
1065         address being_initialized_entry = stub_location - *being_initialized_entry_offset;
1066         if (TracePatching) {
1067           ttyLocker ttyl;
1068           tty->print_cr(" Patching %s at bci %d at address " INTPTR_FORMAT "  (%s)", Bytecodes::name(code), bci,
1069                         p2i(instr_pc), (stub_id == Runtime1::access_field_patching_id) ? "field" : "klass");
1070           nmethod* caller_code = CodeCache::find_nmethod(caller_frame.pc());
1071           assert(caller_code != NULL, "nmethod not found");
1072 
1073           // NOTE we use pc() not original_pc() because we already know they are
1074           // identical otherwise we'd have never entered this block of code
1075 
1076           const ImmutableOopMap* map = caller_code->oop_map_for_return_address(caller_frame.pc());
1077           assert(map != NULL, "null check");
1078           map->print();
1079           tty->cr();
1080 
1081           Disassembler::decode(copy_buff, copy_buff + *byte_count, tty);
1082         }
1083         // depending on the code below, do_patch says whether to copy the patch body back into the nmethod
1084         bool do_patch = true;
1085         if (stub_id == Runtime1::access_field_patching_id) {
1086           // The offset may not be correct if the class was not loaded at code generation time.
1087           // Set it now.
1088           NativeMovRegMem* n_move = nativeMovRegMem_at(copy_buff);
1089           assert(n_move->offset() == 0 || (n_move->offset() == 4 && (patch_field_type == T_DOUBLE || patch_field_type == T_LONG)), "illegal offset for type");
1090           assert(patch_field_offset >= 0, "illegal offset");
1091           n_move->add_offset_in_bytes(patch_field_offset);
1092         } else if (load_klass_or_mirror_patch_id) {
1093           // If a getstatic or putstatic is referencing a klass which
1094           // isn't fully initialized, the patch body isn't copied into
1095           // place until initialization is complete.  In this case the
1096           // patch site is setup so that any threads besides the
1097           // initializing thread are forced to come into the VM and
1098           // block.
1099           do_patch = (code != Bytecodes::_getstatic && code != Bytecodes::_putstatic) ||
1100                      InstanceKlass::cast(init_klass)->is_initialized();
1101           NativeGeneralJump* jump = nativeGeneralJump_at(instr_pc);
1102           if (jump->jump_destination() == being_initialized_entry) {
1103             assert(do_patch == true, "initialization must be complete at this point");
1104           } else {
1105             // patch the instruction <move reg, klass>
1106             NativeMovConstReg* n_copy = nativeMovConstReg_at(copy_buff);
1107 
1108             assert(n_copy->data() == 0 ||
1109                    n_copy->data() == (intptr_t)Universe::non_oop_word(),
1110                    "illegal init value");
1111             if (stub_id == Runtime1::load_klass_patching_id) {
1112               assert(load_klass != NULL, "klass not set");
1113               n_copy->set_data((intx) (load_klass));
1114             } else {
1115               assert(mirror() != NULL, "klass not set");
1116               // Don't need a G1 pre-barrier here since we assert above that data isn't an oop.
1117               n_copy->set_data(cast_from_oop<intx>(mirror()));
1118             }
1119 
1120             if (TracePatching) {
1121               Disassembler::decode(copy_buff, copy_buff + *byte_count, tty);
1122             }
1123           }
1124         } else if (stub_id == Runtime1::load_appendix_patching_id) {
1125           NativeMovConstReg* n_copy = nativeMovConstReg_at(copy_buff);
1126           assert(n_copy->data() == 0 ||
1127                  n_copy->data() == (intptr_t)Universe::non_oop_word(),
1128                  "illegal init value");
1129           n_copy->set_data(cast_from_oop<intx>(appendix()));
1130 
1131           if (TracePatching) {
1132             Disassembler::decode(copy_buff, copy_buff + *byte_count, tty);
1133           }
1134         } else {
1135           ShouldNotReachHere();
1136         }
1137 
1138 #if defined(PPC32)
1139         if (load_klass_or_mirror_patch_id ||
1140             stub_id == Runtime1::load_appendix_patching_id) {
1141           // Update the location in the nmethod with the proper
1142           // metadata.  When the code was generated, a NULL was stuffed
1143           // in the metadata table and that table needs to be update to
1144           // have the right value.  On intel the value is kept
1145           // directly in the instruction instead of in the metadata
1146           // table, so set_data above effectively updated the value.
1147           nmethod* nm = CodeCache::find_nmethod(instr_pc);
1148           assert(nm != NULL, "invalid nmethod_pc");
1149           RelocIterator mds(nm, copy_buff, copy_buff + 1);
1150           bool found = false;
1151           while (mds.next() && !found) {
1152             if (mds.type() == relocInfo::oop_type) {
1153               assert(stub_id == Runtime1::load_mirror_patching_id ||
1154                      stub_id == Runtime1::load_appendix_patching_id, "wrong stub id");
1155               oop_Relocation* r = mds.oop_reloc();
1156               oop* oop_adr = r->oop_addr();
1157               *oop_adr = stub_id == Runtime1::load_mirror_patching_id ? mirror() : appendix();
1158               r->fix_oop_relocation();
1159               found = true;
1160             } else if (mds.type() == relocInfo::metadata_type) {
1161               assert(stub_id == Runtime1::load_klass_patching_id, "wrong stub id");
1162               metadata_Relocation* r = mds.metadata_reloc();
1163               Metadata** metadata_adr = r->metadata_addr();
1164               *metadata_adr = load_klass;
1165               r->fix_metadata_relocation();
1166               found = true;
1167             }
1168           }
1169           assert(found, "the metadata must exist!");
1170         }
1171 #endif
1172         if (do_patch) {
1173           // replace instructions
1174           // first replace the tail, then the call
1175 #ifdef ARM
1176           if((load_klass_or_mirror_patch_id ||
1177               stub_id == Runtime1::load_appendix_patching_id) &&
1178               nativeMovConstReg_at(copy_buff)->is_pc_relative()) {
1179             nmethod* nm = CodeCache::find_nmethod(instr_pc);
1180             address addr = NULL;
1181             assert(nm != NULL, "invalid nmethod_pc");
1182             RelocIterator mds(nm, copy_buff, copy_buff + 1);
1183             while (mds.next()) {
1184               if (mds.type() == relocInfo::oop_type) {
1185                 assert(stub_id == Runtime1::load_mirror_patching_id ||
1186                        stub_id == Runtime1::load_appendix_patching_id, "wrong stub id");
1187                 oop_Relocation* r = mds.oop_reloc();
1188                 addr = (address)r->oop_addr();
1189                 break;
1190               } else if (mds.type() == relocInfo::metadata_type) {
1191                 assert(stub_id == Runtime1::load_klass_patching_id, "wrong stub id");
1192                 metadata_Relocation* r = mds.metadata_reloc();
1193                 addr = (address)r->metadata_addr();
1194                 break;
1195               }
1196             }
1197             assert(addr != NULL, "metadata relocation must exist");
1198             copy_buff -= *byte_count;
1199             NativeMovConstReg* n_copy2 = nativeMovConstReg_at(copy_buff);
1200             n_copy2->set_pc_relative_offset(addr, instr_pc);
1201           }
1202 #endif
1203 
1204           for (int i = NativeGeneralJump::instruction_size; i < *byte_count; i++) {
1205             address ptr = copy_buff + i;
1206             int a_byte = (*ptr) & 0xFF;
1207             address dst = instr_pc + i;
1208             *(unsigned char*)dst = (unsigned char) a_byte;
1209           }
1210           ICache::invalidate_range(instr_pc, *byte_count);
1211           NativeGeneralJump::replace_mt_safe(instr_pc, copy_buff);
1212 
1213           if (load_klass_or_mirror_patch_id ||
1214               stub_id == Runtime1::load_appendix_patching_id) {
1215             relocInfo::relocType rtype =
1216               (stub_id == Runtime1::load_klass_patching_id) ?
1217                                    relocInfo::metadata_type :
1218                                    relocInfo::oop_type;
1219             // update relocInfo to metadata
1220             nmethod* nm = CodeCache::find_nmethod(instr_pc);
1221             assert(nm != NULL, "invalid nmethod_pc");
1222 
1223             // The old patch site is now a move instruction so update
1224             // the reloc info so that it will get updated during
1225             // future GCs.
1226             RelocIterator iter(nm, (address)instr_pc, (address)(instr_pc + 1));
1227             relocInfo::change_reloc_info_for_address(&iter, (address) instr_pc,
1228                                                      relocInfo::none, rtype);
1229 #ifdef PPC32
1230           { address instr_pc2 = instr_pc + NativeMovConstReg::lo_offset;
1231             RelocIterator iter2(nm, instr_pc2, instr_pc2 + 1);
1232             relocInfo::change_reloc_info_for_address(&iter2, (address) instr_pc2,
1233                                                      relocInfo::none, rtype);
1234           }
1235 #endif
1236           }
1237 
1238         } else {
1239           ICache::invalidate_range(copy_buff, *byte_count);
1240           NativeGeneralJump::insert_unconditional(instr_pc, being_initialized_entry);
1241         }
1242       }
1243     }
1244   }
1245 
1246   // If we are patching in a non-perm oop, make sure the nmethod
1247   // is on the right list.
1248   {
1249     MutexLocker ml_code (THREAD, CodeCache_lock, Mutex::_no_safepoint_check_flag);
1250     nmethod* nm = CodeCache::find_nmethod(caller_frame.pc());
1251     guarantee(nm != NULL, "only nmethods can contain non-perm oops");
1252 
1253     // Since we've patched some oops in the nmethod,
1254     // (re)register it with the heap.
1255     Universe::heap()->register_nmethod(nm);
1256   }
1257 JRT_END
1258 
1259 #else // DEOPTIMIZE_WHEN_PATCHING
1260 
1261 JRT_ENTRY(void, Runtime1::patch_code(JavaThread* thread, Runtime1::StubID stub_id ))
1262   RegisterMap reg_map(thread, false);
1263 
1264   NOT_PRODUCT(_patch_code_slowcase_cnt++;)
1265   if (TracePatching) {
1266     tty->print_cr("Deoptimizing because patch is needed");
1267   }
1268 
1269   frame runtime_frame = thread->last_frame();
1270   frame caller_frame = runtime_frame.sender(&reg_map);
1271 
1272   // It's possible the nmethod was invalidated in the last
1273   // safepoint, but if it's still alive then make it not_entrant.
1274   nmethod* nm = CodeCache::find_nmethod(caller_frame.pc());
1275   if (nm != NULL) {
1276     nm->make_not_entrant();
1277   }
1278 
1279   Deoptimization::deoptimize_frame(thread, caller_frame.id());
1280 
1281   // Return to the now deoptimized frame.
1282 JRT_END
1283 
1284 #endif // DEOPTIMIZE_WHEN_PATCHING
1285 
1286 //
1287 // Entry point for compiled code. We want to patch a nmethod.
1288 // We don't do a normal VM transition here because we want to
1289 // know after the patching is complete and any safepoint(s) are taken
1290 // if the calling nmethod was deoptimized. We do this by calling a
1291 // helper method which does the normal VM transition and when it
1292 // completes we can check for deoptimization. This simplifies the
1293 // assembly code in the cpu directories.
1294 //
1295 int Runtime1::move_klass_patching(JavaThread* thread) {
1296 //
1297 // NOTE: we are still in Java
1298 //
1299   Thread* THREAD = thread;
1300   debug_only(NoHandleMark nhm;)
1301   {
1302     // Enter VM mode
1303 
1304     ResetNoHandleMark rnhm;
1305     patch_code(thread, load_klass_patching_id);
1306   }
1307   // Back in JAVA, use no oops DON'T safepoint
1308 
1309   // Return true if calling code is deoptimized
1310 
1311   return caller_is_deopted();
1312 }
1313 
1314 int Runtime1::move_mirror_patching(JavaThread* thread) {
1315 //
1316 // NOTE: we are still in Java
1317 //
1318   Thread* THREAD = thread;
1319   debug_only(NoHandleMark nhm;)
1320   {
1321     // Enter VM mode
1322 
1323     ResetNoHandleMark rnhm;
1324     patch_code(thread, load_mirror_patching_id);
1325   }
1326   // Back in JAVA, use no oops DON'T safepoint
1327 
1328   // Return true if calling code is deoptimized
1329 
1330   return caller_is_deopted();
1331 }
1332 
1333 int Runtime1::move_appendix_patching(JavaThread* thread) {
1334 //
1335 // NOTE: we are still in Java
1336 //
1337   Thread* THREAD = thread;
1338   debug_only(NoHandleMark nhm;)
1339   {
1340     // Enter VM mode
1341 
1342     ResetNoHandleMark rnhm;
1343     patch_code(thread, load_appendix_patching_id);
1344   }
1345   // Back in JAVA, use no oops DON'T safepoint
1346 
1347   // Return true if calling code is deoptimized
1348 
1349   return caller_is_deopted();
1350 }
1351 //
1352 // Entry point for compiled code. We want to patch a nmethod.
1353 // We don't do a normal VM transition here because we want to
1354 // know after the patching is complete and any safepoint(s) are taken
1355 // if the calling nmethod was deoptimized. We do this by calling a
1356 // helper method which does the normal VM transition and when it
1357 // completes we can check for deoptimization. This simplifies the
1358 // assembly code in the cpu directories.
1359 //
1360 
1361 int Runtime1::access_field_patching(JavaThread* thread) {
1362 //
1363 // NOTE: we are still in Java
1364 //
1365   Thread* THREAD = thread;
1366   debug_only(NoHandleMark nhm;)
1367   {
1368     // Enter VM mode
1369 
1370     ResetNoHandleMark rnhm;
1371     patch_code(thread, access_field_patching_id);
1372   }
1373   // Back in JAVA, use no oops DON'T safepoint
1374 
1375   // Return true if calling code is deoptimized
1376 
1377   return caller_is_deopted();
1378 JRT_END
1379 
1380 
1381 JRT_LEAF(void, Runtime1::trace_block_entry(jint block_id))
1382   // for now we just print out the block id
1383   tty->print("%d ", block_id);
1384 JRT_END
1385 
1386 
1387 JRT_LEAF(int, Runtime1::is_instance_of(oopDesc* mirror, oopDesc* obj))
1388   // had to return int instead of bool, otherwise there may be a mismatch
1389   // between the C calling convention and the Java one.
1390   // e.g., on x86, GCC may clear only %al when returning a bool false, but
1391   // JVM takes the whole %eax as the return value, which may misinterpret
1392   // the return value as a boolean true.
1393 
1394   assert(mirror != NULL, "should null-check on mirror before calling");
1395   Klass* k = java_lang_Class::as_Klass(mirror);
1396   return (k != NULL && obj != NULL && obj->is_a(k)) ? 1 : 0;
1397 JRT_END
1398 
1399 JRT_ENTRY(void, Runtime1::predicate_failed_trap(JavaThread* thread))
1400   ResourceMark rm;
1401 
1402   assert(!TieredCompilation, "incompatible with tiered compilation");
1403 
1404   RegisterMap reg_map(thread, false);
1405   frame runtime_frame = thread->last_frame();
1406   frame caller_frame = runtime_frame.sender(&reg_map);
1407 
1408   nmethod* nm = CodeCache::find_nmethod(caller_frame.pc());
1409   assert (nm != NULL, "no more nmethod?");
1410   nm->make_not_entrant();
1411 
1412   methodHandle m(thread, nm->method());
1413   MethodData* mdo = m->method_data();
1414 
1415   if (mdo == NULL && !HAS_PENDING_EXCEPTION) {
1416     // Build an MDO.  Ignore errors like OutOfMemory;
1417     // that simply means we won't have an MDO to update.
1418     Method::build_interpreter_method_data(m, THREAD);
1419     if (HAS_PENDING_EXCEPTION) {
1420       assert((PENDING_EXCEPTION->is_a(SystemDictionary::OutOfMemoryError_klass())), "we expect only an OOM error here");
1421       CLEAR_PENDING_EXCEPTION;
1422     }
1423     mdo = m->method_data();
1424   }
1425 
1426   if (mdo != NULL) {
1427     mdo->inc_trap_count(Deoptimization::Reason_none);
1428   }
1429 
1430   if (TracePredicateFailedTraps) {
1431     stringStream ss1, ss2;
1432     vframeStream vfst(thread);
1433     Method* inlinee = vfst.method();
1434     inlinee->print_short_name(&ss1);
1435     m->print_short_name(&ss2);
1436     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()));
1437   }
1438 
1439 
1440   Deoptimization::deoptimize_frame(thread, caller_frame.id());
1441 
1442 JRT_END
1443 
1444 #ifndef PRODUCT
1445 void Runtime1::print_statistics() {
1446   tty->print_cr("C1 Runtime statistics:");
1447   tty->print_cr(" _resolve_invoke_virtual_cnt:     %d", SharedRuntime::_resolve_virtual_ctr);
1448   tty->print_cr(" _resolve_invoke_opt_virtual_cnt: %d", SharedRuntime::_resolve_opt_virtual_ctr);
1449   tty->print_cr(" _resolve_invoke_static_cnt:      %d", SharedRuntime::_resolve_static_ctr);
1450   tty->print_cr(" _handle_wrong_method_cnt:        %d", SharedRuntime::_wrong_method_ctr);
1451   tty->print_cr(" _ic_miss_cnt:                    %d", SharedRuntime::_ic_miss_ctr);
1452   tty->print_cr(" _generic_arraycopy_cnt:          %d", _generic_arraycopy_cnt);
1453   tty->print_cr(" _generic_arraycopystub_cnt:      %d", _generic_arraycopystub_cnt);
1454   tty->print_cr(" _byte_arraycopy_cnt:             %d", _byte_arraycopy_stub_cnt);
1455   tty->print_cr(" _short_arraycopy_cnt:            %d", _short_arraycopy_stub_cnt);
1456   tty->print_cr(" _int_arraycopy_cnt:              %d", _int_arraycopy_stub_cnt);
1457   tty->print_cr(" _long_arraycopy_cnt:             %d", _long_arraycopy_stub_cnt);
1458   tty->print_cr(" _oop_arraycopy_cnt:              %d", _oop_arraycopy_stub_cnt);
1459   tty->print_cr(" _arraycopy_slowcase_cnt:         %d", _arraycopy_slowcase_cnt);
1460   tty->print_cr(" _arraycopy_checkcast_cnt:        %d", _arraycopy_checkcast_cnt);
1461   tty->print_cr(" _arraycopy_checkcast_attempt_cnt:%d", _arraycopy_checkcast_attempt_cnt);
1462 
1463   tty->print_cr(" _new_type_array_slowcase_cnt:    %d", _new_type_array_slowcase_cnt);
1464   tty->print_cr(" _new_object_array_slowcase_cnt:  %d", _new_object_array_slowcase_cnt);
1465   tty->print_cr(" _new_instance_slowcase_cnt:      %d", _new_instance_slowcase_cnt);
1466   tty->print_cr(" _new_multi_array_slowcase_cnt:   %d", _new_multi_array_slowcase_cnt);
1467   tty->print_cr(" _monitorenter_slowcase_cnt:      %d", _monitorenter_slowcase_cnt);
1468   tty->print_cr(" _monitorexit_slowcase_cnt:       %d", _monitorexit_slowcase_cnt);
1469   tty->print_cr(" _patch_code_slowcase_cnt:        %d", _patch_code_slowcase_cnt);
1470 
1471   tty->print_cr(" _throw_range_check_exception_count:            %d:", _throw_range_check_exception_count);
1472   tty->print_cr(" _throw_index_exception_count:                  %d:", _throw_index_exception_count);
1473   tty->print_cr(" _throw_div0_exception_count:                   %d:", _throw_div0_exception_count);
1474   tty->print_cr(" _throw_null_pointer_exception_count:           %d:", _throw_null_pointer_exception_count);
1475   tty->print_cr(" _throw_class_cast_exception_count:             %d:", _throw_class_cast_exception_count);
1476   tty->print_cr(" _throw_incompatible_class_change_error_count:  %d:", _throw_incompatible_class_change_error_count);
1477   tty->print_cr(" _throw_array_store_exception_count:            %d:", _throw_array_store_exception_count);
1478   tty->print_cr(" _throw_count:                                  %d:", _throw_count);
1479 
1480   SharedRuntime::print_ic_miss_histogram();
1481   tty->cr();
1482 }
1483 #endif // PRODUCT