1 /*
   2  * Copyright (c) 1999, 2014, 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_interface/collectedHeap.hpp"
  42 #include "interpreter/bytecode.hpp"
  43 #include "interpreter/interpreter.hpp"
  44 #include "memory/allocation.inline.hpp"
  45 #include "memory/barrierSet.hpp"
  46 #include "memory/oopFactory.hpp"
  47 #include "memory/resourceArea.hpp"
  48 #include "oops/objArrayKlass.hpp"
  49 #include "oops/oop.inline.hpp"
  50 #include "runtime/biasedLocking.hpp"
  51 #include "runtime/compilationPolicy.hpp"
  52 #include "runtime/interfaceSupport.hpp"
  53 #include "runtime/javaCalls.hpp"
  54 #include "runtime/sharedRuntime.hpp"
  55 #include "runtime/threadCritical.hpp"
  56 #include "runtime/vframe.hpp"
  57 #include "runtime/vframeArray.hpp"
  58 #include "utilities/copy.hpp"
  59 #include "utilities/events.hpp"
  60 
  61 
  62 // Implementation of StubAssembler
  63 
  64 StubAssembler::StubAssembler(CodeBuffer* code, const char * name, int stub_id) : C1_MacroAssembler(code) {
  65   _name = name;
  66   _must_gc_arguments = false;
  67   _frame_size = no_frame_size;
  68   _num_rt_args = 0;
  69   _stub_id = stub_id;
  70 }
  71 
  72 
  73 void StubAssembler::set_info(const char* name, bool must_gc_arguments) {
  74   _name = name;
  75   _must_gc_arguments = must_gc_arguments;
  76 }
  77 
  78 
  79 void StubAssembler::set_frame_size(int size) {
  80   if (_frame_size == no_frame_size) {
  81     _frame_size = size;
  82   }
  83   assert(_frame_size == size, "can't change the frame size");
  84 }
  85 
  86 
  87 void StubAssembler::set_num_rt_args(int args) {
  88   if (_num_rt_args == 0) {
  89     _num_rt_args = args;
  90   }
  91   assert(_num_rt_args == args, "can't change the number of args");
  92 }
  93 
  94 // Implementation of Runtime1
  95 
  96 CodeBlob* Runtime1::_blobs[Runtime1::number_of_ids];
  97 const char *Runtime1::_blob_names[] = {
  98   RUNTIME1_STUBS(STUB_NAME, LAST_STUB_NAME)
  99 };
 100 
 101 #ifndef PRODUCT
 102 // statistics
 103 int Runtime1::_generic_arraycopy_cnt = 0;
 104 int Runtime1::_primitive_arraycopy_cnt = 0;
 105 int Runtime1::_oop_arraycopy_cnt = 0;
 106 int Runtime1::_generic_arraycopystub_cnt = 0;
 107 int Runtime1::_arraycopy_slowcase_cnt = 0;
 108 int Runtime1::_arraycopy_checkcast_cnt = 0;
 109 int Runtime1::_arraycopy_checkcast_attempt_cnt = 0;
 110 int Runtime1::_new_type_array_slowcase_cnt = 0;
 111 int Runtime1::_new_object_array_slowcase_cnt = 0;
 112 int Runtime1::_new_instance_slowcase_cnt = 0;
 113 int Runtime1::_new_multi_array_slowcase_cnt = 0;
 114 int Runtime1::_monitorenter_slowcase_cnt = 0;
 115 int Runtime1::_monitorexit_slowcase_cnt = 0;
 116 int Runtime1::_patch_code_slowcase_cnt = 0;
 117 int Runtime1::_throw_range_check_exception_count = 0;
 118 int Runtime1::_throw_index_exception_count = 0;
 119 int Runtime1::_throw_div0_exception_count = 0;
 120 int Runtime1::_throw_null_pointer_exception_count = 0;
 121 int Runtime1::_throw_class_cast_exception_count = 0;
 122 int Runtime1::_throw_incompatible_class_change_error_count = 0;
 123 int Runtime1::_throw_array_store_exception_count = 0;
 124 int Runtime1::_throw_count = 0;
 125 
 126 static int _byte_arraycopy_cnt = 0;
 127 static int _short_arraycopy_cnt = 0;
 128 static int _int_arraycopy_cnt = 0;
 129 static int _long_arraycopy_cnt = 0;
 130 static int _oop_arraycopy_cnt = 0;
 131 
 132 address Runtime1::arraycopy_count_address(BasicType type) {
 133   switch (type) {
 134   case T_BOOLEAN:
 135   case T_BYTE:   return (address)&_byte_arraycopy_cnt;
 136   case T_CHAR:
 137   case T_SHORT:  return (address)&_short_arraycopy_cnt;
 138   case T_FLOAT:
 139   case T_INT:    return (address)&_int_arraycopy_cnt;
 140   case T_DOUBLE:
 141   case T_LONG:   return (address)&_long_arraycopy_cnt;
 142   case T_ARRAY:
 143   case T_OBJECT: return (address)&_oop_arraycopy_cnt;
 144   default:
 145     ShouldNotReachHere();
 146     return NULL;
 147   }
 148 }
 149 
 150 
 151 #endif
 152 
 153 // Simple helper to see if the caller of a runtime stub which
 154 // entered the VM has been deoptimized
 155 
 156 static bool caller_is_deopted() {
 157   JavaThread* thread = JavaThread::current();
 158   RegisterMap reg_map(thread, false);
 159   frame runtime_frame = thread->last_frame();
 160   frame caller_frame = runtime_frame.sender(&reg_map);
 161   assert(caller_frame.is_compiled_frame(), "must be compiled");
 162   return caller_frame.is_deoptimized_frame();
 163 }
 164 
 165 // Stress deoptimization
 166 static void deopt_caller() {
 167   if ( !caller_is_deopted()) {
 168     JavaThread* thread = JavaThread::current();
 169     RegisterMap reg_map(thread, false);
 170     frame runtime_frame = thread->last_frame();
 171     frame caller_frame = runtime_frame.sender(&reg_map);
 172     Deoptimization::deoptimize_frame(thread, caller_frame.id());
 173     assert(caller_is_deopted(), "Must be deoptimized");
 174   }
 175 }
 176 
 177 
 178 void Runtime1::generate_blob_for(BufferBlob* buffer_blob, StubID id) {
 179   assert(0 <= id && id < number_of_ids, "illegal stub id");
 180   ResourceMark rm;
 181   // create code buffer for code storage
 182   CodeBuffer code(buffer_blob);
 183 
 184   Compilation::setup_code_buffer(&code, 0);
 185 
 186   // create assembler for code generation
 187   StubAssembler* sasm = new StubAssembler(&code, name_for(id), id);
 188   // generate code for runtime stub
 189   OopMapSet* oop_maps;
 190   oop_maps = generate_code_for(id, sasm);
 191   assert(oop_maps == NULL || sasm->frame_size() != no_frame_size,
 192          "if stub has an oop map it must have a valid frame size");
 193 
 194 #ifdef ASSERT
 195   // Make sure that stubs that need oopmaps have them
 196   switch (id) {
 197     // These stubs don't need to have an oopmap
 198     case dtrace_object_alloc_id:
 199     case g1_pre_barrier_slow_id:
 200     case g1_post_barrier_slow_id:
 201     case slow_subtype_check_id:
 202     case fpu2long_stub_id:
 203     case unwind_exception_id:
 204     case counter_overflow_id:
 205 #if defined(SPARC) || defined(PPC)
 206     case handle_exception_nofpu_id:  // Unused on sparc
 207 #endif
 208       break;
 209 
 210     // All other stubs should have oopmaps
 211     default:
 212       assert(oop_maps != NULL, "must have an oopmap");
 213   }
 214 #endif
 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   // create blob - distinguish a few special cases
 221   CodeBlob* blob = RuntimeStub::new_runtime_stub(name_for(id),
 222                                                  &code,
 223                                                  CodeOffsets::frame_never_safe,
 224                                                  sasm->frame_size(),
 225                                                  oop_maps,
 226                                                  sasm->must_gc_arguments());
 227   // install blob
 228   assert(blob != NULL, "blob must exist");
 229   _blobs[id] = blob;
 230 }
 231 
 232 
 233 void Runtime1::initialize(BufferBlob* blob) {
 234   // platform-dependent initialization
 235   initialize_pd();
 236   // generate stubs
 237   for (int id = 0; id < number_of_ids; id++) generate_blob_for(blob, (StubID)id);
 238   // printing
 239 #ifndef PRODUCT
 240   if (PrintSimpleStubs) {
 241     ResourceMark rm;
 242     for (int id = 0; id < number_of_ids; id++) {
 243       _blobs[id]->print();
 244       if (_blobs[id]->oop_maps() != NULL) {
 245         _blobs[id]->oop_maps()->print();
 246       }
 247     }
 248   }
 249 #endif
 250 }
 251 
 252 
 253 CodeBlob* Runtime1::blob_for(StubID id) {
 254   assert(0 <= id && id < number_of_ids, "illegal stub id");
 255   return _blobs[id];
 256 }
 257 
 258 
 259 const char* Runtime1::name_for(StubID id) {
 260   assert(0 <= id && id < number_of_ids, "illegal stub id");
 261   return _blob_names[id];
 262 }
 263 
 264 const char* Runtime1::name_for_address(address entry) {
 265   for (int id = 0; id < number_of_ids; id++) {
 266     if (entry == entry_for((StubID)id)) return name_for((StubID)id);
 267   }
 268 
 269 #define FUNCTION_CASE(a, f) \
 270   if ((intptr_t)a == CAST_FROM_FN_PTR(intptr_t, f))  return #f
 271 
 272   FUNCTION_CASE(entry, os::javaTimeMillis);
 273   FUNCTION_CASE(entry, os::javaTimeNanos);
 274   FUNCTION_CASE(entry, SharedRuntime::OSR_migration_end);
 275   FUNCTION_CASE(entry, SharedRuntime::d2f);
 276   FUNCTION_CASE(entry, SharedRuntime::d2i);
 277   FUNCTION_CASE(entry, SharedRuntime::d2l);
 278   FUNCTION_CASE(entry, SharedRuntime::dcos);
 279   FUNCTION_CASE(entry, SharedRuntime::dexp);
 280   FUNCTION_CASE(entry, SharedRuntime::dlog);
 281   FUNCTION_CASE(entry, SharedRuntime::dlog10);
 282   FUNCTION_CASE(entry, SharedRuntime::dpow);
 283   FUNCTION_CASE(entry, SharedRuntime::drem);
 284   FUNCTION_CASE(entry, SharedRuntime::dsin);
 285   FUNCTION_CASE(entry, SharedRuntime::dtan);
 286   FUNCTION_CASE(entry, SharedRuntime::f2i);
 287   FUNCTION_CASE(entry, SharedRuntime::f2l);
 288   FUNCTION_CASE(entry, SharedRuntime::frem);
 289   FUNCTION_CASE(entry, SharedRuntime::l2d);
 290   FUNCTION_CASE(entry, SharedRuntime::l2f);
 291   FUNCTION_CASE(entry, SharedRuntime::ldiv);
 292   FUNCTION_CASE(entry, SharedRuntime::lmul);
 293   FUNCTION_CASE(entry, SharedRuntime::lrem);
 294   FUNCTION_CASE(entry, SharedRuntime::lrem);
 295   FUNCTION_CASE(entry, SharedRuntime::dtrace_method_entry);
 296   FUNCTION_CASE(entry, SharedRuntime::dtrace_method_exit);
 297   FUNCTION_CASE(entry, is_instance_of);
 298   FUNCTION_CASE(entry, trace_block_entry);
 299 #ifdef TRACE_HAVE_INTRINSICS
 300   FUNCTION_CASE(entry, TRACE_TIME_METHOD);
 301 #endif
 302   FUNCTION_CASE(entry, StubRoutines::updateBytesCRC32());
 303 
 304 #undef FUNCTION_CASE
 305 
 306   // Soft float adds more runtime names.
 307   return pd_name_for_address(entry);
 308 }
 309 
 310 
 311 JRT_ENTRY(void, Runtime1::new_instance(JavaThread* thread, Klass* klass))
 312   NOT_PRODUCT(_new_instance_slowcase_cnt++;)
 313 
 314   assert(klass->is_klass(), "not a class");
 315   instanceKlassHandle h(thread, klass);
 316   h->check_valid_for_instantiation(true, CHECK);
 317   // make sure klass is initialized
 318   h->initialize(CHECK);
 319   // allocate instance and return via TLS
 320   oop obj = h->allocate_instance(CHECK);
 321   thread->set_vm_result(obj);
 322 JRT_END
 323 
 324 
 325 JRT_ENTRY(void, Runtime1::new_type_array(JavaThread* thread, Klass* klass, jint length))
 326   NOT_PRODUCT(_new_type_array_slowcase_cnt++;)
 327   // Note: no handle for klass needed since they are not used
 328   //       anymore after new_typeArray() and no GC can happen before.
 329   //       (This may have to change if this code changes!)
 330   assert(klass->is_klass(), "not a class");
 331   BasicType elt_type = TypeArrayKlass::cast(klass)->element_type();
 332   oop obj = oopFactory::new_typeArray(elt_type, length, CHECK);
 333   thread->set_vm_result(obj);
 334   // This is pretty rare but this runtime patch is stressful to deoptimization
 335   // if we deoptimize here so force a deopt to stress the path.
 336   if (DeoptimizeALot) {
 337     deopt_caller();
 338   }
 339 
 340 JRT_END
 341 
 342 
 343 JRT_ENTRY(void, Runtime1::new_object_array(JavaThread* thread, Klass* array_klass, jint length))
 344   NOT_PRODUCT(_new_object_array_slowcase_cnt++;)
 345 
 346   // Note: no handle for klass needed since they are not used
 347   //       anymore after new_objArray() and no GC can happen before.
 348   //       (This may have to change if this code changes!)
 349   assert(array_klass->is_klass(), "not a class");
 350   Klass* elem_klass = ObjArrayKlass::cast(array_klass)->element_klass();
 351   objArrayOop obj = oopFactory::new_objArray(elem_klass, length, CHECK);
 352   thread->set_vm_result(obj);
 353   // This is pretty rare but this runtime patch is stressful to deoptimization
 354   // if we deoptimize here so force a deopt to stress the path.
 355   if (DeoptimizeALot) {
 356     deopt_caller();
 357   }
 358 JRT_END
 359 
 360 
 361 JRT_ENTRY(void, Runtime1::new_multi_array(JavaThread* thread, Klass* klass, int rank, jint* dims))
 362   NOT_PRODUCT(_new_multi_array_slowcase_cnt++;)
 363 
 364   assert(klass->is_klass(), "not a class");
 365   assert(rank >= 1, "rank must be nonzero");
 366   oop obj = ArrayKlass::cast(klass)->multi_allocate(rank, dims, CHECK);
 367   thread->set_vm_result(obj);
 368 JRT_END
 369 
 370 
 371 JRT_ENTRY(void, Runtime1::unimplemented_entry(JavaThread* thread, StubID id))
 372   tty->print_cr("Runtime1::entry_for(%d) returned unimplemented entry point", id);
 373 JRT_END
 374 
 375 
 376 JRT_ENTRY(void, Runtime1::throw_array_store_exception(JavaThread* thread, oopDesc* obj))
 377   ResourceMark rm(thread);
 378   const char* klass_name = obj->klass()->external_name();
 379   SharedRuntime::throw_and_post_jvmti_exception(thread, vmSymbols::java_lang_ArrayStoreException(), klass_name);
 380 JRT_END
 381 
 382 
 383 // counter_overflow() is called from within C1-compiled methods. The enclosing method is the method
 384 // associated with the top activation record. The inlinee (that is possibly included in the enclosing
 385 // method) method oop is passed as an argument. In order to do that it is embedded in the code as
 386 // a constant.
 387 static nmethod* counter_overflow_helper(JavaThread* THREAD, int branch_bci, Method* m) {
 388   nmethod* osr_nm = NULL;
 389   methodHandle method(THREAD, m);
 390 
 391   RegisterMap map(THREAD, false);
 392   frame fr =  THREAD->last_frame().sender(&map);
 393   nmethod* nm = (nmethod*) fr.cb();
 394   assert(nm!= NULL && nm->is_nmethod(), "Sanity check");
 395   methodHandle enclosing_method(THREAD, nm->method());
 396 
 397   CompLevel level = (CompLevel)nm->comp_level();
 398   int bci = InvocationEntryBci;
 399   if (branch_bci != InvocationEntryBci) {
 400     // Compute desination bci
 401     address pc = method()->code_base() + branch_bci;
 402     Bytecodes::Code branch = Bytecodes::code_at(method(), pc);
 403     int offset = 0;
 404     switch (branch) {
 405       case Bytecodes::_if_icmplt: case Bytecodes::_iflt:
 406       case Bytecodes::_if_icmpgt: case Bytecodes::_ifgt:
 407       case Bytecodes::_if_icmple: case Bytecodes::_ifle:
 408       case Bytecodes::_if_icmpge: case Bytecodes::_ifge:
 409       case Bytecodes::_if_icmpeq: case Bytecodes::_if_acmpeq: case Bytecodes::_ifeq:
 410       case Bytecodes::_if_icmpne: case Bytecodes::_if_acmpne: case Bytecodes::_ifne:
 411       case Bytecodes::_ifnull: case Bytecodes::_ifnonnull: case Bytecodes::_goto:
 412         offset = (int16_t)Bytes::get_Java_u2(pc + 1);
 413         break;
 414       case Bytecodes::_goto_w:
 415         offset = Bytes::get_Java_u4(pc + 1);
 416         break;
 417       default: ;
 418     }
 419     bci = branch_bci + offset;
 420   }
 421   assert(!HAS_PENDING_EXCEPTION, "Should not have any exceptions pending");
 422   osr_nm = CompilationPolicy::policy()->event(enclosing_method, method, branch_bci, bci, level, nm, THREAD);
 423   assert(!HAS_PENDING_EXCEPTION, "Event handler should not throw any exceptions");
 424   return osr_nm;
 425 }
 426 
 427 JRT_BLOCK_ENTRY(address, Runtime1::counter_overflow(JavaThread* thread, int bci, Method* method))
 428   nmethod* osr_nm;
 429   JRT_BLOCK
 430     osr_nm = counter_overflow_helper(thread, bci, method);
 431     if (osr_nm != NULL) {
 432       RegisterMap map(thread, false);
 433       frame fr =  thread->last_frame().sender(&map);
 434       Deoptimization::deoptimize_frame(thread, fr.id());
 435     }
 436   JRT_BLOCK_END
 437   return NULL;
 438 JRT_END
 439 
 440 extern void vm_exit(int code);
 441 
 442 // Enter this method from compiled code handler below. This is where we transition
 443 // to VM mode. This is done as a helper routine so that the method called directly
 444 // from compiled code does not have to transition to VM. This allows the entry
 445 // method to see if the nmethod that we have just looked up a handler for has
 446 // been deoptimized while we were in the vm. This simplifies the assembly code
 447 // cpu directories.
 448 //
 449 // We are entering here from exception stub (via the entry method below)
 450 // If there is a compiled exception handler in this method, we will continue there;
 451 // otherwise we will unwind the stack and continue at the caller of top frame method
 452 // Note: we enter in Java using a special JRT wrapper. This wrapper allows us to
 453 // control the area where we can allow a safepoint. After we exit the safepoint area we can
 454 // check to see if the handler we are going to return is now in a nmethod that has
 455 // been deoptimized. If that is the case we return the deopt blob
 456 // unpack_with_exception entry instead. This makes life for the exception blob easier
 457 // because making that same check and diverting is painful from assembly language.
 458 JRT_ENTRY_NO_ASYNC(static address, exception_handler_for_pc_helper(JavaThread* thread, oopDesc* ex, address pc, nmethod*& nm))
 459   // Reset method handle flag.
 460   thread->set_is_method_handle_return(false);
 461 
 462   Handle exception(thread, ex);
 463   nm = CodeCache::find_nmethod(pc);
 464   assert(nm != NULL, "this is not an nmethod");
 465   // Adjust the pc as needed/
 466   if (nm->is_deopt_pc(pc)) {
 467     RegisterMap map(thread, false);
 468     frame exception_frame = thread->last_frame().sender(&map);
 469     // if the frame isn't deopted then pc must not correspond to the caller of last_frame
 470     assert(exception_frame.is_deoptimized_frame(), "must be deopted");
 471     pc = exception_frame.pc();
 472   }
 473 #ifdef ASSERT
 474   assert(exception.not_null(), "NULL exceptions should be handled by throw_exception");
 475   assert(exception->is_oop(), "just checking");
 476   // Check that exception is a subclass of Throwable, otherwise we have a VerifyError
 477   if (!(exception->is_a(SystemDictionary::Throwable_klass()))) {
 478     if (ExitVMOnVerifyError) vm_exit(-1);
 479     ShouldNotReachHere();
 480   }
 481 #endif
 482 
 483   // Check the stack guard pages and reenable them if necessary and there is
 484   // enough space on the stack to do so.  Use fast exceptions only if the guard
 485   // pages are enabled.
 486   bool guard_pages_enabled = thread->stack_yellow_zone_enabled();
 487   if (!guard_pages_enabled) guard_pages_enabled = thread->reguard_stack();
 488 
 489   if (JvmtiExport::can_post_on_exceptions()) {
 490     // To ensure correct notification of exception catches and throws
 491     // we have to deoptimize here.  If we attempted to notify the
 492     // catches and throws during this exception lookup it's possible
 493     // we could deoptimize on the way out of the VM and end back in
 494     // the interpreter at the throw site.  This would result in double
 495     // notifications since the interpreter would also notify about
 496     // these same catches and throws as it unwound the frame.
 497 
 498     RegisterMap reg_map(thread);
 499     frame stub_frame = thread->last_frame();
 500     frame caller_frame = stub_frame.sender(&reg_map);
 501 
 502     // We don't really want to deoptimize the nmethod itself since we
 503     // can actually continue in the exception handler ourselves but I
 504     // don't see an easy way to have the desired effect.
 505     Deoptimization::deoptimize_frame(thread, caller_frame.id());
 506     assert(caller_is_deopted(), "Must be deoptimized");
 507 
 508     return SharedRuntime::deopt_blob()->unpack_with_exception_in_tls();
 509   }
 510 
 511   // ExceptionCache is used only for exceptions at call sites and not for implicit exceptions
 512   if (guard_pages_enabled) {
 513     address fast_continuation = nm->handler_for_exception_and_pc(exception, pc);
 514     if (fast_continuation != NULL) {
 515       // Set flag if return address is a method handle call site.
 516       thread->set_is_method_handle_return(nm->is_method_handle_return(pc));
 517       return fast_continuation;
 518     }
 519   }
 520 
 521   // If the stack guard pages are enabled, check whether there is a handler in
 522   // the current method.  Otherwise (guard pages disabled), force an unwind and
 523   // skip the exception cache update (i.e., just leave continuation==NULL).
 524   address continuation = NULL;
 525   if (guard_pages_enabled) {
 526 
 527     // New exception handling mechanism can support inlined methods
 528     // with exception handlers since the mappings are from PC to PC
 529 
 530     // debugging support
 531     // tracing
 532     if (TraceExceptions) {
 533       ttyLocker ttyl;
 534       ResourceMark rm;
 535       tty->print_cr("Exception <%s> (" INTPTR_FORMAT ") thrown in compiled method <%s> at PC " INTPTR_FORMAT " for thread " INTPTR_FORMAT "",
 536                     exception->print_value_string(), p2i((address)exception()), nm->method()->print_value_string(), p2i(pc), p2i(thread));
 537     }
 538     // for AbortVMOnException flag
 539     NOT_PRODUCT(Exceptions::debug_check_abort(exception));
 540 
 541     // Clear out the exception oop and pc since looking up an
 542     // exception handler can cause class loading, which might throw an
 543     // exception and those fields are expected to be clear during
 544     // normal bytecode execution.
 545     thread->clear_exception_oop_and_pc();
 546 
 547     Handle original_exception(thread, exception());
 548 
 549     continuation = SharedRuntime::compute_compiled_exc_handler(nm, pc, exception, false, false);
 550     // If an exception was thrown during exception dispatch, the exception oop may have changed
 551     thread->set_exception_oop(exception());
 552     thread->set_exception_pc(pc);
 553 
 554     // the exception cache is used only by non-implicit exceptions
 555     // Update the exception cache only when there didn't happen
 556     // another exception during the computation of the compiled
 557     // exception handler.
 558     if (continuation != NULL && original_exception() == exception()) {
 559       nm->add_handler_for_exception_and_pc(exception, pc, continuation);
 560     }
 561   }
 562 
 563   thread->set_vm_result(exception());
 564   // Set flag if return address is a method handle call site.
 565   thread->set_is_method_handle_return(nm->is_method_handle_return(pc));
 566 
 567   if (TraceExceptions) {
 568     ttyLocker ttyl;
 569     ResourceMark rm;
 570     tty->print_cr("Thread " PTR_FORMAT " continuing at PC " PTR_FORMAT " for exception thrown at PC " PTR_FORMAT,
 571                   p2i(thread), p2i(continuation), p2i(pc));
 572   }
 573 
 574   return continuation;
 575 JRT_END
 576 
 577 // Enter this method from compiled code only if there is a Java exception handler
 578 // in the method handling the exception.
 579 // We are entering here from exception stub. We don't do a normal VM transition here.
 580 // We do it in a helper. This is so we can check to see if the nmethod we have just
 581 // searched for an exception handler has been deoptimized in the meantime.
 582 address Runtime1::exception_handler_for_pc(JavaThread* thread) {
 583   oop exception = thread->exception_oop();
 584   address pc = thread->exception_pc();
 585   // Still in Java mode
 586   DEBUG_ONLY(ResetNoHandleMark rnhm);
 587   nmethod* nm = NULL;
 588   address continuation = NULL;
 589   {
 590     // Enter VM mode by calling the helper
 591     ResetNoHandleMark rnhm;
 592     continuation = exception_handler_for_pc_helper(thread, exception, pc, nm);
 593   }
 594   // Back in JAVA, use no oops DON'T safepoint
 595 
 596   // Now check to see if the nmethod we were called from is now deoptimized.
 597   // If so we must return to the deopt blob and deoptimize the nmethod
 598   if (nm != NULL && caller_is_deopted()) {
 599     continuation = SharedRuntime::deopt_blob()->unpack_with_exception_in_tls();
 600   }
 601 
 602   assert(continuation != NULL, "no handler found");
 603   return continuation;
 604 }
 605 
 606 
 607 JRT_ENTRY(void, Runtime1::throw_range_check_exception(JavaThread* thread, int index))
 608   NOT_PRODUCT(_throw_range_check_exception_count++;)
 609   char message[jintAsStringSize];
 610   sprintf(message, "%d", index);
 611   SharedRuntime::throw_and_post_jvmti_exception(thread, vmSymbols::java_lang_ArrayIndexOutOfBoundsException(), message);
 612 JRT_END
 613 
 614 
 615 JRT_ENTRY(void, Runtime1::throw_index_exception(JavaThread* thread, int index))
 616   NOT_PRODUCT(_throw_index_exception_count++;)
 617   char message[16];
 618   sprintf(message, "%d", index);
 619   SharedRuntime::throw_and_post_jvmti_exception(thread, vmSymbols::java_lang_IndexOutOfBoundsException(), message);
 620 JRT_END
 621 
 622 
 623 JRT_ENTRY(void, Runtime1::throw_div0_exception(JavaThread* thread))
 624   NOT_PRODUCT(_throw_div0_exception_count++;)
 625   SharedRuntime::throw_and_post_jvmti_exception(thread, vmSymbols::java_lang_ArithmeticException(), "/ by zero");
 626 JRT_END
 627 
 628 
 629 JRT_ENTRY(void, Runtime1::throw_null_pointer_exception(JavaThread* thread))
 630   NOT_PRODUCT(_throw_null_pointer_exception_count++;)
 631   SharedRuntime::throw_and_post_jvmti_exception(thread, vmSymbols::java_lang_NullPointerException());
 632 JRT_END
 633 
 634 
 635 JRT_ENTRY(void, Runtime1::throw_class_cast_exception(JavaThread* thread, oopDesc* object))
 636   NOT_PRODUCT(_throw_class_cast_exception_count++;)
 637   ResourceMark rm(thread);
 638   char* message = SharedRuntime::generate_class_cast_message(
 639     thread, object->klass()->external_name());
 640   SharedRuntime::throw_and_post_jvmti_exception(
 641     thread, vmSymbols::java_lang_ClassCastException(), message);
 642 JRT_END
 643 
 644 
 645 JRT_ENTRY(void, Runtime1::throw_incompatible_class_change_error(JavaThread* thread))
 646   NOT_PRODUCT(_throw_incompatible_class_change_error_count++;)
 647   ResourceMark rm(thread);
 648   SharedRuntime::throw_and_post_jvmti_exception(thread, vmSymbols::java_lang_IncompatibleClassChangeError());
 649 JRT_END
 650 
 651 
 652 JRT_ENTRY_NO_ASYNC(void, Runtime1::monitorenter(JavaThread* thread, oopDesc* obj, BasicObjectLock* lock))
 653   NOT_PRODUCT(_monitorenter_slowcase_cnt++;)
 654   if (PrintBiasedLockingStatistics) {
 655     Atomic::inc(BiasedLocking::slow_path_entry_count_addr());
 656   }
 657   Handle h_obj(thread, obj);
 658   assert(h_obj()->is_oop(), "must be NULL or an object");
 659   if (UseBiasedLocking) {
 660     // Retry fast entry if bias is revoked to avoid unnecessary inflation
 661     ObjectSynchronizer::fast_enter(h_obj, lock->lock(), true, CHECK);
 662   } else {
 663     if (UseFastLocking) {
 664       // When using fast locking, the compiled code has already tried the fast case
 665       assert(obj == lock->obj(), "must match");
 666       ObjectSynchronizer::slow_enter(h_obj, lock->lock(), THREAD);
 667     } else {
 668       lock->set_obj(obj);
 669       ObjectSynchronizer::fast_enter(h_obj, lock->lock(), false, THREAD);
 670     }
 671   }
 672 JRT_END
 673 
 674 
 675 JRT_LEAF(void, Runtime1::monitorexit(JavaThread* thread, BasicObjectLock* lock))
 676   NOT_PRODUCT(_monitorexit_slowcase_cnt++;)
 677   assert(thread == JavaThread::current(), "threads must correspond");
 678   assert(thread->last_Java_sp(), "last_Java_sp must be set");
 679   // monitorexit is non-blocking (leaf routine) => no exceptions can be thrown
 680   EXCEPTION_MARK;
 681 
 682   oop obj = lock->obj();
 683   assert(obj->is_oop(), "must be NULL or an object");
 684   if (UseFastLocking) {
 685     // When using fast locking, the compiled code has already tried the fast case
 686     ObjectSynchronizer::slow_exit(obj, lock->lock(), THREAD);
 687   } else {
 688     ObjectSynchronizer::fast_exit(obj, lock->lock(), THREAD);
 689   }
 690 JRT_END
 691 
 692 // Cf. OptoRuntime::deoptimize_caller_frame
 693 JRT_ENTRY(void, Runtime1::deoptimize(JavaThread* thread))
 694   // Called from within the owner thread, so no need for safepoint
 695   RegisterMap reg_map(thread, false);
 696   frame stub_frame = thread->last_frame();
 697   assert(stub_frame.is_runtime_frame(), "sanity check");
 698   frame caller_frame = stub_frame.sender(&reg_map);
 699 
 700   // We are coming from a compiled method; check this is true.
 701   assert(CodeCache::find_nmethod(caller_frame.pc()) != NULL, "sanity");
 702 
 703   // Deoptimize the caller frame.
 704   Deoptimization::deoptimize_frame(thread, caller_frame.id());
 705 
 706   // Return to the now deoptimized frame.
 707 JRT_END
 708 
 709 
 710 static Klass* resolve_field_return_klass(methodHandle caller, int bci, TRAPS) {
 711   Bytecode_field field_access(caller, bci);
 712   // This can be static or non-static field access
 713   Bytecodes::Code code       = field_access.code();
 714 
 715   // We must load class, initialize class and resolvethe field
 716   fieldDescriptor result; // initialize class if needed
 717   constantPoolHandle constants(THREAD, caller->constants());
 718   LinkResolver::resolve_field_access(result, constants, field_access.index(), Bytecodes::java_code(code), CHECK_NULL);
 719   return result.field_holder();
 720 }
 721 
 722 
 723 //
 724 // This routine patches sites where a class wasn't loaded or
 725 // initialized at the time the code was generated.  It handles
 726 // references to classes, fields and forcing of initialization.  Most
 727 // of the cases are straightforward and involving simply forcing
 728 // resolution of a class, rewriting the instruction stream with the
 729 // needed constant and replacing the call in this function with the
 730 // patched code.  The case for static field is more complicated since
 731 // the thread which is in the process of initializing a class can
 732 // access it's static fields but other threads can't so the code
 733 // either has to deoptimize when this case is detected or execute a
 734 // check that the current thread is the initializing thread.  The
 735 // current
 736 //
 737 // Patches basically look like this:
 738 //
 739 //
 740 // patch_site: jmp patch stub     ;; will be patched
 741 // continue:   ...
 742 //             ...
 743 //             ...
 744 //             ...
 745 //
 746 // They have a stub which looks like this:
 747 //
 748 //             ;; patch body
 749 //             movl <const>, reg           (for class constants)
 750 //        <or> movl [reg1 + <const>], reg  (for field offsets)
 751 //        <or> movl reg, [reg1 + <const>]  (for field offsets)
 752 //             <being_init offset> <bytes to copy> <bytes to skip>
 753 // patch_stub: call Runtime1::patch_code (through a runtime stub)
 754 //             jmp patch_site
 755 //
 756 //
 757 // A normal patch is done by rewriting the patch body, usually a move,
 758 // and then copying it into place over top of the jmp instruction
 759 // being careful to flush caches and doing it in an MP-safe way.  The
 760 // constants following the patch body are used to find various pieces
 761 // of the patch relative to the call site for Runtime1::patch_code.
 762 // The case for getstatic and putstatic is more complicated because
 763 // getstatic and putstatic have special semantics when executing while
 764 // the class is being initialized.  getstatic/putstatic on a class
 765 // which is being_initialized may be executed by the initializing
 766 // thread but other threads have to block when they execute it.  This
 767 // is accomplished in compiled code by executing a test of the current
 768 // thread against the initializing thread of the class.  It's emitted
 769 // as boilerplate in their stub which allows the patched code to be
 770 // executed before it's copied back into the main body of the nmethod.
 771 //
 772 // being_init: get_thread(<tmp reg>
 773 //             cmpl [reg1 + <init_thread_offset>], <tmp reg>
 774 //             jne patch_stub
 775 //             movl [reg1 + <const>], reg  (for field offsets)  <or>
 776 //             movl reg, [reg1 + <const>]  (for field offsets)
 777 //             jmp continue
 778 //             <being_init offset> <bytes to copy> <bytes to skip>
 779 // patch_stub: jmp Runtim1::patch_code (through a runtime stub)
 780 //             jmp patch_site
 781 //
 782 // If the class is being initialized the patch body is rewritten and
 783 // the patch site is rewritten to jump to being_init, instead of
 784 // patch_stub.  Whenever this code is executed it checks the current
 785 // thread against the intializing thread so other threads will enter
 786 // the runtime and end up blocked waiting the class to finish
 787 // initializing inside the calls to resolve_field below.  The
 788 // initializing class will continue on it's way.  Once the class is
 789 // fully_initialized, the intializing_thread of the class becomes
 790 // NULL, so the next thread to execute this code will fail the test,
 791 // call into patch_code and complete the patching process by copying
 792 // the patch body back into the main part of the nmethod and resume
 793 // executing.
 794 //
 795 //
 796 
 797 JRT_ENTRY(void, Runtime1::patch_code(JavaThread* thread, Runtime1::StubID stub_id ))
 798   NOT_PRODUCT(_patch_code_slowcase_cnt++;)
 799 
 800   ResourceMark rm(thread);
 801   RegisterMap reg_map(thread, false);
 802   frame runtime_frame = thread->last_frame();
 803   frame caller_frame = runtime_frame.sender(&reg_map);
 804 
 805   // last java frame on stack
 806   vframeStream vfst(thread, true);
 807   assert(!vfst.at_end(), "Java frame must exist");
 808 
 809   methodHandle caller_method(THREAD, vfst.method());
 810   // Note that caller_method->code() may not be same as caller_code because of OSR's
 811   // Note also that in the presence of inlining it is not guaranteed
 812   // that caller_method() == caller_code->method()
 813 
 814   int bci = vfst.bci();
 815   Bytecodes::Code code = caller_method()->java_code_at(bci);
 816 
 817 #ifndef PRODUCT
 818   // this is used by assertions in the access_field_patching_id
 819   BasicType patch_field_type = T_ILLEGAL;
 820 #endif // PRODUCT
 821   bool deoptimize_for_volatile = false;
 822   int patch_field_offset = -1;
 823   KlassHandle init_klass(THREAD, NULL); // klass needed by load_klass_patching code
 824   KlassHandle load_klass(THREAD, NULL); // klass needed by load_klass_patching code
 825   Handle mirror(THREAD, NULL);                    // oop needed by load_mirror_patching code
 826   Handle appendix(THREAD, NULL);                  // oop needed by appendix_patching code
 827   bool load_klass_or_mirror_patch_id =
 828     (stub_id == Runtime1::load_klass_patching_id || stub_id == Runtime1::load_mirror_patching_id);
 829 
 830   if (stub_id == Runtime1::access_field_patching_id) {
 831 
 832     Bytecode_field field_access(caller_method, bci);
 833     fieldDescriptor result; // initialize class if needed
 834     Bytecodes::Code code = field_access.code();
 835     constantPoolHandle constants(THREAD, caller_method->constants());
 836     LinkResolver::resolve_field_access(result, constants, field_access.index(), Bytecodes::java_code(code), CHECK);
 837     patch_field_offset = result.offset();
 838 
 839     // If we're patching a field which is volatile then at compile it
 840     // must not have been know to be volatile, so the generated code
 841     // isn't correct for a volatile reference.  The nmethod has to be
 842     // deoptimized so that the code can be regenerated correctly.
 843     // This check is only needed for access_field_patching since this
 844     // is the path for patching field offsets.  load_klass is only
 845     // used for patching references to oops which don't need special
 846     // handling in the volatile case.
 847     deoptimize_for_volatile = result.access_flags().is_volatile();
 848 
 849 #ifndef PRODUCT
 850     patch_field_type = result.field_type();
 851 #endif
 852   } else if (load_klass_or_mirror_patch_id) {
 853     Klass* k = NULL;
 854     switch (code) {
 855       case Bytecodes::_putstatic:
 856       case Bytecodes::_getstatic:
 857         { Klass* klass = resolve_field_return_klass(caller_method, bci, CHECK);
 858           init_klass = KlassHandle(THREAD, klass);
 859           mirror = Handle(THREAD, klass->java_mirror());
 860         }
 861         break;
 862       case Bytecodes::_new:
 863         { Bytecode_new bnew(caller_method(), caller_method->bcp_from(bci));
 864           k = caller_method->constants()->klass_at(bnew.index(), CHECK);
 865         }
 866         break;
 867       case Bytecodes::_multianewarray:
 868         { Bytecode_multianewarray mna(caller_method(), caller_method->bcp_from(bci));
 869           k = caller_method->constants()->klass_at(mna.index(), CHECK);
 870         }
 871         break;
 872       case Bytecodes::_instanceof:
 873         { Bytecode_instanceof io(caller_method(), caller_method->bcp_from(bci));
 874           k = caller_method->constants()->klass_at(io.index(), CHECK);
 875         }
 876         break;
 877       case Bytecodes::_checkcast:
 878         { Bytecode_checkcast cc(caller_method(), caller_method->bcp_from(bci));
 879           k = caller_method->constants()->klass_at(cc.index(), CHECK);
 880         }
 881         break;
 882       case Bytecodes::_anewarray:
 883         { Bytecode_anewarray anew(caller_method(), caller_method->bcp_from(bci));
 884           Klass* ek = caller_method->constants()->klass_at(anew.index(), CHECK);
 885           k = ek->array_klass(CHECK);
 886         }
 887         break;
 888       case Bytecodes::_ldc:
 889       case Bytecodes::_ldc_w:
 890         {
 891           Bytecode_loadconstant cc(caller_method, bci);
 892           oop m = cc.resolve_constant(CHECK);
 893           mirror = Handle(THREAD, m);
 894         }
 895         break;
 896       default: fatal("unexpected bytecode for load_klass_or_mirror_patch_id");
 897     }
 898     // convert to handle
 899     load_klass = KlassHandle(THREAD, k);
 900   } else if (stub_id == load_appendix_patching_id) {
 901     Bytecode_invoke bytecode(caller_method, bci);
 902     Bytecodes::Code bc = bytecode.invoke_code();
 903 
 904     CallInfo info;
 905     constantPoolHandle pool(thread, caller_method->constants());
 906     int index = bytecode.index();
 907     LinkResolver::resolve_invoke(info, Handle(), pool, index, bc, CHECK);
 908     appendix = info.resolved_appendix();
 909     switch (bc) {
 910       case Bytecodes::_invokehandle: {
 911         int cache_index = ConstantPool::decode_cpcache_index(index, true);
 912         assert(cache_index >= 0 && cache_index < pool->cache()->length(), "unexpected cache index");
 913         pool->cache()->entry_at(cache_index)->set_method_handle(pool, info);
 914         break;
 915       }
 916       case Bytecodes::_invokedynamic: {
 917         pool->invokedynamic_cp_cache_entry_at(index)->set_dynamic_call(pool, info);
 918         break;
 919       }
 920       default: fatal("unexpected bytecode for load_appendix_patching_id");
 921     }
 922   } else {
 923     ShouldNotReachHere();
 924   }
 925 
 926   if (deoptimize_for_volatile) {
 927     // At compile time we assumed the field wasn't volatile but after
 928     // loading it turns out it was volatile so we have to throw the
 929     // compiled code out and let it be regenerated.
 930     if (TracePatching) {
 931       tty->print_cr("Deoptimizing for patching volatile field reference");
 932     }
 933     // It's possible the nmethod was invalidated in the last
 934     // safepoint, but if it's still alive then make it not_entrant.
 935     nmethod* nm = CodeCache::find_nmethod(caller_frame.pc());
 936     if (nm != NULL) {
 937       nm->make_not_entrant();
 938     }
 939 
 940     Deoptimization::deoptimize_frame(thread, caller_frame.id());
 941 
 942     // Return to the now deoptimized frame.
 943   }
 944 
 945   // Now copy code back
 946 
 947   {
 948     MutexLockerEx ml_patch (Patching_lock, Mutex::_no_safepoint_check_flag);
 949     //
 950     // Deoptimization may have happened while we waited for the lock.
 951     // In that case we don't bother to do any patching we just return
 952     // and let the deopt happen
 953     if (!caller_is_deopted()) {
 954       NativeGeneralJump* jump = nativeGeneralJump_at(caller_frame.pc());
 955       address instr_pc = jump->jump_destination();
 956       NativeInstruction* ni = nativeInstruction_at(instr_pc);
 957       if (ni->is_jump() ) {
 958         // the jump has not been patched yet
 959         // The jump destination is slow case and therefore not part of the stubs
 960         // (stubs are only for StaticCalls)
 961 
 962         // format of buffer
 963         //    ....
 964         //    instr byte 0     <-- copy_buff
 965         //    instr byte 1
 966         //    ..
 967         //    instr byte n-1
 968         //      n
 969         //    ....             <-- call destination
 970 
 971         address stub_location = caller_frame.pc() + PatchingStub::patch_info_offset();
 972         unsigned char* byte_count = (unsigned char*) (stub_location - 1);
 973         unsigned char* byte_skip = (unsigned char*) (stub_location - 2);
 974         unsigned char* being_initialized_entry_offset = (unsigned char*) (stub_location - 3);
 975         address copy_buff = stub_location - *byte_skip - *byte_count;
 976         address being_initialized_entry = stub_location - *being_initialized_entry_offset;
 977         if (TracePatching) {
 978           tty->print_cr(" Patching %s at bci %d at address " INTPTR_FORMAT "  (%s)", Bytecodes::name(code), bci,
 979                         p2i(instr_pc), (stub_id == Runtime1::access_field_patching_id) ? "field" : "klass");
 980           nmethod* caller_code = CodeCache::find_nmethod(caller_frame.pc());
 981           assert(caller_code != NULL, "nmethod not found");
 982 
 983           // NOTE we use pc() not original_pc() because we already know they are
 984           // identical otherwise we'd have never entered this block of code
 985 
 986           OopMap* map = caller_code->oop_map_for_return_address(caller_frame.pc());
 987           assert(map != NULL, "null check");
 988           map->print();
 989           tty->cr();
 990 
 991           Disassembler::decode(copy_buff, copy_buff + *byte_count, tty);
 992         }
 993         // depending on the code below, do_patch says whether to copy the patch body back into the nmethod
 994         bool do_patch = true;
 995         if (stub_id == Runtime1::access_field_patching_id) {
 996           // The offset may not be correct if the class was not loaded at code generation time.
 997           // Set it now.
 998           NativeMovRegMem* n_move = nativeMovRegMem_at(copy_buff);
 999           assert(n_move->offset() == 0 || (n_move->offset() == 4 && (patch_field_type == T_DOUBLE || patch_field_type == T_LONG)), "illegal offset for type");
1000           assert(patch_field_offset >= 0, "illegal offset");
1001           n_move->add_offset_in_bytes(patch_field_offset);
1002         } else if (load_klass_or_mirror_patch_id) {
1003           // If a getstatic or putstatic is referencing a klass which
1004           // isn't fully initialized, the patch body isn't copied into
1005           // place until initialization is complete.  In this case the
1006           // patch site is setup so that any threads besides the
1007           // initializing thread are forced to come into the VM and
1008           // block.
1009           do_patch = (code != Bytecodes::_getstatic && code != Bytecodes::_putstatic) ||
1010                      InstanceKlass::cast(init_klass())->is_initialized();
1011           NativeGeneralJump* jump = nativeGeneralJump_at(instr_pc);
1012           if (jump->jump_destination() == being_initialized_entry) {
1013             assert(do_patch == true, "initialization must be complete at this point");
1014           } else {
1015             // patch the instruction <move reg, klass>
1016             NativeMovConstReg* n_copy = nativeMovConstReg_at(copy_buff);
1017 
1018             assert(n_copy->data() == 0 ||
1019                    n_copy->data() == (intptr_t)Universe::non_oop_word(),
1020                    "illegal init value");
1021             if (stub_id == Runtime1::load_klass_patching_id) {
1022               assert(load_klass() != NULL, "klass not set");
1023               n_copy->set_data((intx) (load_klass()));
1024             } else {
1025               assert(mirror() != NULL, "klass not set");
1026               // Don't need a G1 pre-barrier here since we assert above that data isn't an oop.
1027               n_copy->set_data(cast_from_oop<intx>(mirror()));
1028             }
1029 
1030             if (TracePatching) {
1031               Disassembler::decode(copy_buff, copy_buff + *byte_count, tty);
1032             }
1033           }
1034         } else if (stub_id == Runtime1::load_appendix_patching_id) {
1035           NativeMovConstReg* n_copy = nativeMovConstReg_at(copy_buff);
1036           assert(n_copy->data() == 0 ||
1037                  n_copy->data() == (intptr_t)Universe::non_oop_word(),
1038                  "illegal init value");
1039           n_copy->set_data(cast_from_oop<intx>(appendix()));
1040 
1041           if (TracePatching) {
1042             Disassembler::decode(copy_buff, copy_buff + *byte_count, tty);
1043           }
1044         } else {
1045           ShouldNotReachHere();
1046         }
1047 
1048 #if defined(SPARC) || defined(PPC)
1049         if (load_klass_or_mirror_patch_id ||
1050             stub_id == Runtime1::load_appendix_patching_id) {
1051           // Update the location in the nmethod with the proper
1052           // metadata.  When the code was generated, a NULL was stuffed
1053           // in the metadata table and that table needs to be update to
1054           // have the right value.  On intel the value is kept
1055           // directly in the instruction instead of in the metadata
1056           // table, so set_data above effectively updated the value.
1057           nmethod* nm = CodeCache::find_nmethod(instr_pc);
1058           assert(nm != NULL, "invalid nmethod_pc");
1059           RelocIterator mds(nm, copy_buff, copy_buff + 1);
1060           bool found = false;
1061           while (mds.next() && !found) {
1062             if (mds.type() == relocInfo::oop_type) {
1063               assert(stub_id == Runtime1::load_mirror_patching_id ||
1064                      stub_id == Runtime1::load_appendix_patching_id, "wrong stub id");
1065               oop_Relocation* r = mds.oop_reloc();
1066               oop* oop_adr = r->oop_addr();
1067               *oop_adr = stub_id == Runtime1::load_mirror_patching_id ? mirror() : appendix();
1068               r->fix_oop_relocation();
1069               found = true;
1070             } else if (mds.type() == relocInfo::metadata_type) {
1071               assert(stub_id == Runtime1::load_klass_patching_id, "wrong stub id");
1072               metadata_Relocation* r = mds.metadata_reloc();
1073               Metadata** metadata_adr = r->metadata_addr();
1074               *metadata_adr = load_klass();
1075               r->fix_metadata_relocation();
1076               found = true;
1077             }
1078           }
1079           assert(found, "the metadata must exist!");
1080         }
1081 #endif
1082         if (do_patch) {
1083           // replace instructions
1084           // first replace the tail, then the call
1085 #ifdef ARM
1086           if((load_klass_or_mirror_patch_id ||
1087               stub_id == Runtime1::load_appendix_patching_id) &&
1088               nativeMovConstReg_at(copy_buff)->is_pc_relative()) {
1089             nmethod* nm = CodeCache::find_nmethod(instr_pc);
1090             address addr = NULL;
1091             assert(nm != NULL, "invalid nmethod_pc");
1092             RelocIterator mds(nm, copy_buff, copy_buff + 1);
1093             while (mds.next()) {
1094               if (mds.type() == relocInfo::oop_type) {
1095                 assert(stub_id == Runtime1::load_mirror_patching_id ||
1096                        stub_id == Runtime1::load_appendix_patching_id, "wrong stub id");
1097                 oop_Relocation* r = mds.oop_reloc();
1098                 addr = (address)r->oop_addr();
1099                 break;
1100               } else if (mds.type() == relocInfo::metadata_type) {
1101                 assert(stub_id == Runtime1::load_klass_patching_id, "wrong stub id");
1102                 metadata_Relocation* r = mds.metadata_reloc();
1103                 addr = (address)r->metadata_addr();
1104                 break;
1105               }
1106             }
1107             assert(addr != NULL, "metadata relocation must exist");
1108             copy_buff -= *byte_count;
1109             NativeMovConstReg* n_copy2 = nativeMovConstReg_at(copy_buff);
1110             n_copy2->set_pc_relative_offset(addr, instr_pc);
1111           }
1112 #endif
1113 
1114           for (int i = NativeCall::instruction_size; i < *byte_count; i++) {
1115             address ptr = copy_buff + i;
1116             int a_byte = (*ptr) & 0xFF;
1117             address dst = instr_pc + i;
1118             *(unsigned char*)dst = (unsigned char) a_byte;
1119           }
1120           ICache::invalidate_range(instr_pc, *byte_count);
1121           NativeGeneralJump::replace_mt_safe(instr_pc, copy_buff);
1122 
1123           if (load_klass_or_mirror_patch_id ||
1124               stub_id == Runtime1::load_appendix_patching_id) {
1125             relocInfo::relocType rtype =
1126               (stub_id == Runtime1::load_klass_patching_id) ?
1127                                    relocInfo::metadata_type :
1128                                    relocInfo::oop_type;
1129             // update relocInfo to metadata
1130             nmethod* nm = CodeCache::find_nmethod(instr_pc);
1131             assert(nm != NULL, "invalid nmethod_pc");
1132 
1133             // The old patch site is now a move instruction so update
1134             // the reloc info so that it will get updated during
1135             // future GCs.
1136             RelocIterator iter(nm, (address)instr_pc, (address)(instr_pc + 1));
1137             relocInfo::change_reloc_info_for_address(&iter, (address) instr_pc,
1138                                                      relocInfo::none, rtype);
1139 #ifdef SPARC
1140             // Sparc takes two relocations for an metadata so update the second one.
1141             address instr_pc2 = instr_pc + NativeMovConstReg::add_offset;
1142             RelocIterator iter2(nm, instr_pc2, instr_pc2 + 1);
1143             relocInfo::change_reloc_info_for_address(&iter2, (address) instr_pc2,
1144                                                      relocInfo::none, rtype);
1145 #endif
1146 #ifdef PPC
1147           { address instr_pc2 = instr_pc + NativeMovConstReg::lo_offset;
1148             RelocIterator iter2(nm, instr_pc2, instr_pc2 + 1);
1149             relocInfo::change_reloc_info_for_address(&iter2, (address) instr_pc2,
1150                                                      relocInfo::none, rtype);
1151           }
1152 #endif
1153           }
1154 
1155         } else {
1156           ICache::invalidate_range(copy_buff, *byte_count);
1157           NativeGeneralJump::insert_unconditional(instr_pc, being_initialized_entry);
1158         }
1159       }
1160     }
1161   }
1162 
1163   // If we are patching in a non-perm oop, make sure the nmethod
1164   // is on the right list.
1165   if (ScavengeRootsInCode && ((mirror.not_null() && mirror()->is_scavengable()) ||
1166                               (appendix.not_null() && appendix->is_scavengable()))) {
1167     MutexLockerEx ml_code (CodeCache_lock, Mutex::_no_safepoint_check_flag);
1168     nmethod* nm = CodeCache::find_nmethod(caller_frame.pc());
1169     guarantee(nm != NULL, "only nmethods can contain non-perm oops");
1170     if (!nm->on_scavenge_root_list()) {
1171       CodeCache::add_scavenge_root_nmethod(nm);
1172     }
1173 
1174     // Since we've patched some oops in the nmethod,
1175     // (re)register it with the heap.
1176     Universe::heap()->register_nmethod(nm);
1177   }
1178 JRT_END
1179 
1180 //
1181 // Entry point for compiled code. We want to patch a nmethod.
1182 // We don't do a normal VM transition here because we want to
1183 // know after the patching is complete and any safepoint(s) are taken
1184 // if the calling nmethod was deoptimized. We do this by calling a
1185 // helper method which does the normal VM transition and when it
1186 // completes we can check for deoptimization. This simplifies the
1187 // assembly code in the cpu directories.
1188 //
1189 int Runtime1::move_klass_patching(JavaThread* thread) {
1190 //
1191 // NOTE: we are still in Java
1192 //
1193   Thread* THREAD = thread;
1194   debug_only(NoHandleMark nhm;)
1195   {
1196     // Enter VM mode
1197 
1198     ResetNoHandleMark rnhm;
1199     patch_code(thread, load_klass_patching_id);
1200   }
1201   // Back in JAVA, use no oops DON'T safepoint
1202 
1203   // Return true if calling code is deoptimized
1204 
1205   return caller_is_deopted();
1206 }
1207 
1208 int Runtime1::move_mirror_patching(JavaThread* thread) {
1209 //
1210 // NOTE: we are still in Java
1211 //
1212   Thread* THREAD = thread;
1213   debug_only(NoHandleMark nhm;)
1214   {
1215     // Enter VM mode
1216 
1217     ResetNoHandleMark rnhm;
1218     patch_code(thread, load_mirror_patching_id);
1219   }
1220   // Back in JAVA, use no oops DON'T safepoint
1221 
1222   // Return true if calling code is deoptimized
1223 
1224   return caller_is_deopted();
1225 }
1226 
1227 int Runtime1::move_appendix_patching(JavaThread* thread) {
1228 //
1229 // NOTE: we are still in Java
1230 //
1231   Thread* THREAD = thread;
1232   debug_only(NoHandleMark nhm;)
1233   {
1234     // Enter VM mode
1235 
1236     ResetNoHandleMark rnhm;
1237     patch_code(thread, load_appendix_patching_id);
1238   }
1239   // Back in JAVA, use no oops DON'T safepoint
1240 
1241   // Return true if calling code is deoptimized
1242 
1243   return caller_is_deopted();
1244 }
1245 //
1246 // Entry point for compiled code. We want to patch a nmethod.
1247 // We don't do a normal VM transition here because we want to
1248 // know after the patching is complete and any safepoint(s) are taken
1249 // if the calling nmethod was deoptimized. We do this by calling a
1250 // helper method which does the normal VM transition and when it
1251 // completes we can check for deoptimization. This simplifies the
1252 // assembly code in the cpu directories.
1253 //
1254 
1255 int Runtime1::access_field_patching(JavaThread* thread) {
1256 //
1257 // NOTE: we are still in Java
1258 //
1259   Thread* THREAD = thread;
1260   debug_only(NoHandleMark nhm;)
1261   {
1262     // Enter VM mode
1263 
1264     ResetNoHandleMark rnhm;
1265     patch_code(thread, access_field_patching_id);
1266   }
1267   // Back in JAVA, use no oops DON'T safepoint
1268 
1269   // Return true if calling code is deoptimized
1270 
1271   return caller_is_deopted();
1272 JRT_END
1273 
1274 
1275 JRT_LEAF(void, Runtime1::trace_block_entry(jint block_id))
1276   // for now we just print out the block id
1277   tty->print("%d ", block_id);
1278 JRT_END
1279 
1280 
1281 // Array copy return codes.
1282 enum {
1283   ac_failed = -1, // arraycopy failed
1284   ac_ok = 0       // arraycopy succeeded
1285 };
1286 
1287 
1288 // Below length is the # elements copied.
1289 template <class T> int obj_arraycopy_work(oopDesc* src, T* src_addr,
1290                                           oopDesc* dst, T* dst_addr,
1291                                           int length) {
1292 
1293   // For performance reasons, we assume we are using a card marking write
1294   // barrier. The assert will fail if this is not the case.
1295   // Note that we use the non-virtual inlineable variant of write_ref_array.
1296   BarrierSet* bs = Universe::heap()->barrier_set();
1297   assert(bs->has_write_ref_array_opt(), "Barrier set must have ref array opt");
1298   assert(bs->has_write_ref_array_pre_opt(), "For pre-barrier as well.");
1299   if (src == dst) {
1300     // same object, no check
1301     bs->write_ref_array_pre(dst_addr, length);
1302     Copy::conjoint_oops_atomic(src_addr, dst_addr, length);
1303     bs->write_ref_array((HeapWord*)dst_addr, length);
1304     return ac_ok;
1305   } else {
1306     Klass* bound = ObjArrayKlass::cast(dst->klass())->element_klass();
1307     Klass* stype = ObjArrayKlass::cast(src->klass())->element_klass();
1308     if (stype == bound || stype->is_subtype_of(bound)) {
1309       // Elements are guaranteed to be subtypes, so no check necessary
1310       bs->write_ref_array_pre(dst_addr, length);
1311       Copy::conjoint_oops_atomic(src_addr, dst_addr, length);
1312       bs->write_ref_array((HeapWord*)dst_addr, length);
1313       return ac_ok;
1314     }
1315   }
1316   return ac_failed;
1317 }
1318 
1319 // fast and direct copy of arrays; returning -1, means that an exception may be thrown
1320 // and we did not copy anything
1321 JRT_LEAF(int, Runtime1::arraycopy(oopDesc* src, int src_pos, oopDesc* dst, int dst_pos, int length))
1322 #ifndef PRODUCT
1323   _generic_arraycopy_cnt++;        // Slow-path oop array copy
1324 #endif
1325 
1326   if (src == NULL || dst == NULL || src_pos < 0 || dst_pos < 0 || length < 0) return ac_failed;
1327   if (!dst->is_array() || !src->is_array()) return ac_failed;
1328   if ((unsigned int) arrayOop(src)->length() < (unsigned int)src_pos + (unsigned int)length) return ac_failed;
1329   if ((unsigned int) arrayOop(dst)->length() < (unsigned int)dst_pos + (unsigned int)length) return ac_failed;
1330 
1331   if (length == 0) return ac_ok;
1332   if (src->is_typeArray()) {
1333     Klass* klass_oop = src->klass();
1334     if (klass_oop != dst->klass()) return ac_failed;
1335     TypeArrayKlass* klass = TypeArrayKlass::cast(klass_oop);
1336     const int l2es = klass->log2_element_size();
1337     const int ihs = klass->array_header_in_bytes() / wordSize;
1338     char* src_addr = (char*) ((oopDesc**)src + ihs) + (src_pos << l2es);
1339     char* dst_addr = (char*) ((oopDesc**)dst + ihs) + (dst_pos << l2es);
1340     // Potential problem: memmove is not guaranteed to be word atomic
1341     // Revisit in Merlin
1342     memmove(dst_addr, src_addr, length << l2es);
1343     return ac_ok;
1344   } else if (src->is_objArray() && dst->is_objArray()) {
1345     if (UseCompressedOops) {
1346       narrowOop *src_addr  = objArrayOop(src)->obj_at_addr<narrowOop>(src_pos);
1347       narrowOop *dst_addr  = objArrayOop(dst)->obj_at_addr<narrowOop>(dst_pos);
1348       return obj_arraycopy_work(src, src_addr, dst, dst_addr, length);
1349     } else {
1350       oop *src_addr  = objArrayOop(src)->obj_at_addr<oop>(src_pos);
1351       oop *dst_addr  = objArrayOop(dst)->obj_at_addr<oop>(dst_pos);
1352       return obj_arraycopy_work(src, src_addr, dst, dst_addr, length);
1353     }
1354   }
1355   return ac_failed;
1356 JRT_END
1357 
1358 
1359 JRT_LEAF(void, Runtime1::primitive_arraycopy(HeapWord* src, HeapWord* dst, int length))
1360 #ifndef PRODUCT
1361   _primitive_arraycopy_cnt++;
1362 #endif
1363 
1364   if (length == 0) return;
1365   // Not guaranteed to be word atomic, but that doesn't matter
1366   // for anything but an oop array, which is covered by oop_arraycopy.
1367   Copy::conjoint_jbytes(src, dst, length);
1368 JRT_END
1369 
1370 JRT_LEAF(void, Runtime1::oop_arraycopy(HeapWord* src, HeapWord* dst, int num))
1371 #ifndef PRODUCT
1372   _oop_arraycopy_cnt++;
1373 #endif
1374 
1375   if (num == 0) return;
1376   BarrierSet* bs = Universe::heap()->barrier_set();
1377   assert(bs->has_write_ref_array_opt(), "Barrier set must have ref array opt");
1378   assert(bs->has_write_ref_array_pre_opt(), "For pre-barrier as well.");
1379   if (UseCompressedOops) {
1380     bs->write_ref_array_pre((narrowOop*)dst, num);
1381     Copy::conjoint_oops_atomic((narrowOop*) src, (narrowOop*) dst, num);
1382   } else {
1383     bs->write_ref_array_pre((oop*)dst, num);
1384     Copy::conjoint_oops_atomic((oop*) src, (oop*) dst, num);
1385   }
1386   bs->write_ref_array(dst, num);
1387 JRT_END
1388 
1389 
1390 JRT_LEAF(int, Runtime1::is_instance_of(oopDesc* mirror, oopDesc* obj))
1391   // had to return int instead of bool, otherwise there may be a mismatch
1392   // between the C calling convention and the Java one.
1393   // e.g., on x86, GCC may clear only %al when returning a bool false, but
1394   // JVM takes the whole %eax as the return value, which may misinterpret
1395   // the return value as a boolean true.
1396 
1397   assert(mirror != NULL, "should null-check on mirror before calling");
1398   Klass* k = java_lang_Class::as_Klass(mirror);
1399   return (k != NULL && obj != NULL && obj->is_a(k)) ? 1 : 0;
1400 JRT_END
1401 
1402 JRT_ENTRY(void, Runtime1::predicate_failed_trap(JavaThread* thread))
1403   ResourceMark rm;
1404 
1405   assert(!TieredCompilation, "incompatible with tiered compilation");
1406 
1407   RegisterMap reg_map(thread, false);
1408   frame runtime_frame = thread->last_frame();
1409   frame caller_frame = runtime_frame.sender(&reg_map);
1410 
1411   nmethod* nm = CodeCache::find_nmethod(caller_frame.pc());
1412   assert (nm != NULL, "no more nmethod?");
1413   nm->make_not_entrant();
1414 
1415   methodHandle m(nm->method());
1416   MethodData* mdo = m->method_data();
1417 
1418   if (mdo == NULL && !HAS_PENDING_EXCEPTION) {
1419     // Build an MDO.  Ignore errors like OutOfMemory;
1420     // that simply means we won't have an MDO to update.
1421     Method::build_interpreter_method_data(m, THREAD);
1422     if (HAS_PENDING_EXCEPTION) {
1423       assert((PENDING_EXCEPTION->is_a(SystemDictionary::OutOfMemoryError_klass())), "we expect only an OOM error here");
1424       CLEAR_PENDING_EXCEPTION;
1425     }
1426     mdo = m->method_data();
1427   }
1428 
1429   if (mdo != NULL) {
1430     mdo->inc_trap_count(Deoptimization::Reason_none);
1431   }
1432 
1433   if (TracePredicateFailedTraps) {
1434     stringStream ss1, ss2;
1435     vframeStream vfst(thread);
1436     methodHandle inlinee = methodHandle(vfst.method());
1437     inlinee->print_short_name(&ss1);
1438     m->print_short_name(&ss2);
1439     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()));
1440   }
1441 
1442 
1443   Deoptimization::deoptimize_frame(thread, caller_frame.id());
1444 
1445 JRT_END
1446 
1447 #ifndef PRODUCT
1448 void Runtime1::print_statistics() {
1449   tty->print_cr("C1 Runtime statistics:");
1450   tty->print_cr(" _resolve_invoke_virtual_cnt:     %d", SharedRuntime::_resolve_virtual_ctr);
1451   tty->print_cr(" _resolve_invoke_opt_virtual_cnt: %d", SharedRuntime::_resolve_opt_virtual_ctr);
1452   tty->print_cr(" _resolve_invoke_static_cnt:      %d", SharedRuntime::_resolve_static_ctr);
1453   tty->print_cr(" _handle_wrong_method_cnt:        %d", SharedRuntime::_wrong_method_ctr);
1454   tty->print_cr(" _ic_miss_cnt:                    %d", SharedRuntime::_ic_miss_ctr);
1455   tty->print_cr(" _generic_arraycopy_cnt:          %d", _generic_arraycopy_cnt);
1456   tty->print_cr(" _generic_arraycopystub_cnt:      %d", _generic_arraycopystub_cnt);
1457   tty->print_cr(" _byte_arraycopy_cnt:             %d", _byte_arraycopy_cnt);
1458   tty->print_cr(" _short_arraycopy_cnt:            %d", _short_arraycopy_cnt);
1459   tty->print_cr(" _int_arraycopy_cnt:              %d", _int_arraycopy_cnt);
1460   tty->print_cr(" _long_arraycopy_cnt:             %d", _long_arraycopy_cnt);
1461   tty->print_cr(" _primitive_arraycopy_cnt:        %d", _primitive_arraycopy_cnt);
1462   tty->print_cr(" _oop_arraycopy_cnt (C):          %d", Runtime1::_oop_arraycopy_cnt);
1463   tty->print_cr(" _oop_arraycopy_cnt (stub):       %d", _oop_arraycopy_cnt);
1464   tty->print_cr(" _arraycopy_slowcase_cnt:         %d", _arraycopy_slowcase_cnt);
1465   tty->print_cr(" _arraycopy_checkcast_cnt:        %d", _arraycopy_checkcast_cnt);
1466   tty->print_cr(" _arraycopy_checkcast_attempt_cnt:%d", _arraycopy_checkcast_attempt_cnt);
1467 
1468   tty->print_cr(" _new_type_array_slowcase_cnt:    %d", _new_type_array_slowcase_cnt);
1469   tty->print_cr(" _new_object_array_slowcase_cnt:  %d", _new_object_array_slowcase_cnt);
1470   tty->print_cr(" _new_instance_slowcase_cnt:      %d", _new_instance_slowcase_cnt);
1471   tty->print_cr(" _new_multi_array_slowcase_cnt:   %d", _new_multi_array_slowcase_cnt);
1472   tty->print_cr(" _monitorenter_slowcase_cnt:      %d", _monitorenter_slowcase_cnt);
1473   tty->print_cr(" _monitorexit_slowcase_cnt:       %d", _monitorexit_slowcase_cnt);
1474   tty->print_cr(" _patch_code_slowcase_cnt:        %d", _patch_code_slowcase_cnt);
1475 
1476   tty->print_cr(" _throw_range_check_exception_count:            %d:", _throw_range_check_exception_count);
1477   tty->print_cr(" _throw_index_exception_count:                  %d:", _throw_index_exception_count);
1478   tty->print_cr(" _throw_div0_exception_count:                   %d:", _throw_div0_exception_count);
1479   tty->print_cr(" _throw_null_pointer_exception_count:           %d:", _throw_null_pointer_exception_count);
1480   tty->print_cr(" _throw_class_cast_exception_count:             %d:", _throw_class_cast_exception_count);
1481   tty->print_cr(" _throw_incompatible_class_change_error_count:  %d:", _throw_incompatible_class_change_error_count);
1482   tty->print_cr(" _throw_array_store_exception_count:            %d:", _throw_array_store_exception_count);
1483   tty->print_cr(" _throw_count:                                  %d:", _throw_count);
1484 
1485   SharedRuntime::print_ic_miss_histogram();
1486   tty->cr();
1487 }
1488 #endif // PRODUCT