1 /*
   2  * Copyright (c) 1997, 2024, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #include "precompiled.hpp"
  26 #include "classfile/javaClasses.inline.hpp"
  27 #include "classfile/stringTable.hpp"
  28 #include "classfile/vmClasses.hpp"
  29 #include "classfile/vmSymbols.hpp"
  30 #include "code/codeCache.hpp"
  31 #include "code/compiledIC.hpp"
  32 #include "code/compiledMethod.inline.hpp"
  33 #include "code/scopeDesc.hpp"
  34 #include "code/vtableStubs.hpp"
  35 #include "compiler/abstractCompiler.hpp"
  36 #include "compiler/compileBroker.hpp"
  37 #include "compiler/disassembler.hpp"
  38 #include "gc/shared/barrierSet.hpp"
  39 #include "gc/shared/collectedHeap.hpp"
  40 #include "gc/shared/gcLocker.inline.hpp"
  41 #include "interpreter/interpreter.hpp"
  42 #include "interpreter/interpreterRuntime.hpp"
  43 #include "jvm.h"
  44 #include "jfr/jfrEvents.hpp"
  45 #include "logging/log.hpp"
  46 #include "memory/resourceArea.hpp"
  47 #include "memory/universe.hpp"
  48 #include "metaprogramming/primitiveConversions.hpp"
  49 #include "oops/klass.hpp"
  50 #include "oops/method.inline.hpp"
  51 #include "oops/objArrayKlass.hpp"
  52 #include "oops/oop.inline.hpp"
  53 #include "prims/forte.hpp"
  54 #include "prims/jvmtiExport.hpp"
  55 #include "prims/jvmtiThreadState.hpp"
  56 #include "prims/methodHandles.hpp"
  57 #include "prims/nativeLookup.hpp"
  58 #include "runtime/atomic.hpp"
  59 #include "runtime/frame.inline.hpp"
  60 #include "runtime/handles.inline.hpp"
  61 #include "runtime/init.hpp"
  62 #include "runtime/interfaceSupport.inline.hpp"
  63 #include "runtime/java.hpp"
  64 #include "runtime/javaCalls.hpp"
  65 #include "runtime/jniHandles.inline.hpp"
  66 #include "runtime/objectMonitor.inline.hpp"
  67 #include "runtime/sharedRuntime.hpp"
  68 #include "runtime/stackWatermarkSet.hpp"
  69 #include "runtime/stubRoutines.hpp"
  70 #include "runtime/synchronizer.hpp"
  71 #include "runtime/vframe.inline.hpp"
  72 #include "runtime/vframeArray.hpp"
  73 #include "runtime/vm_version.hpp"
  74 #include "utilities/copy.hpp"
  75 #include "utilities/dtrace.hpp"
  76 #include "utilities/events.hpp"
  77 #include "utilities/resourceHash.hpp"
  78 #include "utilities/macros.hpp"
  79 #include "utilities/xmlstream.hpp"
  80 #ifdef COMPILER1
  81 #include "c1/c1_Runtime1.hpp"
  82 #endif
  83 #if INCLUDE_JFR
  84 #include "jfr/jfr.hpp"
  85 #endif
  86 
  87 // Shared stub locations
  88 RuntimeStub*        SharedRuntime::_wrong_method_blob;
  89 RuntimeStub*        SharedRuntime::_wrong_method_abstract_blob;
  90 RuntimeStub*        SharedRuntime::_ic_miss_blob;
  91 RuntimeStub*        SharedRuntime::_resolve_opt_virtual_call_blob;
  92 RuntimeStub*        SharedRuntime::_resolve_virtual_call_blob;
  93 RuntimeStub*        SharedRuntime::_resolve_static_call_blob;
  94 address             SharedRuntime::_resolve_static_call_entry;
  95 
  96 DeoptimizationBlob* SharedRuntime::_deopt_blob;
  97 SafepointBlob*      SharedRuntime::_polling_page_vectors_safepoint_handler_blob;
  98 SafepointBlob*      SharedRuntime::_polling_page_safepoint_handler_blob;
  99 SafepointBlob*      SharedRuntime::_polling_page_return_handler_blob;
 100 
 101 #ifdef COMPILER2
 102 UncommonTrapBlob*   SharedRuntime::_uncommon_trap_blob;
 103 #endif // COMPILER2
 104 
 105 nmethod*            SharedRuntime::_cont_doYield_stub;
 106 
 107 //----------------------------generate_stubs-----------------------------------
 108 void SharedRuntime::generate_stubs() {
 109   _wrong_method_blob                   = generate_resolve_blob(CAST_FROM_FN_PTR(address, SharedRuntime::handle_wrong_method),          "wrong_method_stub");
 110   _wrong_method_abstract_blob          = generate_resolve_blob(CAST_FROM_FN_PTR(address, SharedRuntime::handle_wrong_method_abstract), "wrong_method_abstract_stub");
 111   _ic_miss_blob                        = generate_resolve_blob(CAST_FROM_FN_PTR(address, SharedRuntime::handle_wrong_method_ic_miss),  "ic_miss_stub");
 112   _resolve_opt_virtual_call_blob       = generate_resolve_blob(CAST_FROM_FN_PTR(address, SharedRuntime::resolve_opt_virtual_call_C),   "resolve_opt_virtual_call");
 113   _resolve_virtual_call_blob           = generate_resolve_blob(CAST_FROM_FN_PTR(address, SharedRuntime::resolve_virtual_call_C),       "resolve_virtual_call");
 114   _resolve_static_call_blob            = generate_resolve_blob(CAST_FROM_FN_PTR(address, SharedRuntime::resolve_static_call_C),        "resolve_static_call");
 115   _resolve_static_call_entry           = _resolve_static_call_blob->entry_point();
 116 
 117   AdapterHandlerLibrary::initialize();
 118 
 119 #if COMPILER2_OR_JVMCI
 120   // Vectors are generated only by C2 and JVMCI.
 121   bool support_wide = is_wide_vector(MaxVectorSize);
 122   if (support_wide) {
 123     _polling_page_vectors_safepoint_handler_blob = generate_handler_blob(CAST_FROM_FN_PTR(address, SafepointSynchronize::handle_polling_page_exception), POLL_AT_VECTOR_LOOP);
 124   }
 125 #endif // COMPILER2_OR_JVMCI
 126   _polling_page_safepoint_handler_blob = generate_handler_blob(CAST_FROM_FN_PTR(address, SafepointSynchronize::handle_polling_page_exception), POLL_AT_LOOP);
 127   _polling_page_return_handler_blob    = generate_handler_blob(CAST_FROM_FN_PTR(address, SafepointSynchronize::handle_polling_page_exception), POLL_AT_RETURN);
 128 
 129   generate_deopt_blob();
 130 
 131 #ifdef COMPILER2
 132   generate_uncommon_trap_blob();
 133 #endif // COMPILER2
 134 }
 135 
 136 #include <math.h>
 137 
 138 // Implementation of SharedRuntime
 139 
 140 #ifndef PRODUCT
 141 // For statistics
 142 uint SharedRuntime::_ic_miss_ctr = 0;
 143 uint SharedRuntime::_wrong_method_ctr = 0;
 144 uint SharedRuntime::_resolve_static_ctr = 0;
 145 uint SharedRuntime::_resolve_virtual_ctr = 0;
 146 uint SharedRuntime::_resolve_opt_virtual_ctr = 0;
 147 uint SharedRuntime::_implicit_null_throws = 0;
 148 uint SharedRuntime::_implicit_div0_throws = 0;
 149 
 150 int64_t SharedRuntime::_nof_normal_calls = 0;
 151 int64_t SharedRuntime::_nof_inlined_calls = 0;
 152 int64_t SharedRuntime::_nof_megamorphic_calls = 0;
 153 int64_t SharedRuntime::_nof_static_calls = 0;
 154 int64_t SharedRuntime::_nof_inlined_static_calls = 0;
 155 int64_t SharedRuntime::_nof_interface_calls = 0;
 156 int64_t SharedRuntime::_nof_inlined_interface_calls = 0;
 157 
 158 uint SharedRuntime::_new_instance_ctr=0;
 159 uint SharedRuntime::_new_array_ctr=0;
 160 uint SharedRuntime::_multi2_ctr=0;
 161 uint SharedRuntime::_multi3_ctr=0;
 162 uint SharedRuntime::_multi4_ctr=0;
 163 uint SharedRuntime::_multi5_ctr=0;
 164 uint SharedRuntime::_mon_enter_stub_ctr=0;
 165 uint SharedRuntime::_mon_exit_stub_ctr=0;
 166 uint SharedRuntime::_mon_enter_ctr=0;
 167 uint SharedRuntime::_mon_exit_ctr=0;
 168 uint SharedRuntime::_partial_subtype_ctr=0;
 169 uint SharedRuntime::_jbyte_array_copy_ctr=0;
 170 uint SharedRuntime::_jshort_array_copy_ctr=0;
 171 uint SharedRuntime::_jint_array_copy_ctr=0;
 172 uint SharedRuntime::_jlong_array_copy_ctr=0;
 173 uint SharedRuntime::_oop_array_copy_ctr=0;
 174 uint SharedRuntime::_checkcast_array_copy_ctr=0;
 175 uint SharedRuntime::_unsafe_array_copy_ctr=0;
 176 uint SharedRuntime::_generic_array_copy_ctr=0;
 177 uint SharedRuntime::_slow_array_copy_ctr=0;
 178 uint SharedRuntime::_find_handler_ctr=0;
 179 uint SharedRuntime::_rethrow_ctr=0;
 180 
 181 int     SharedRuntime::_ICmiss_index                    = 0;
 182 int     SharedRuntime::_ICmiss_count[SharedRuntime::maxICmiss_count];
 183 address SharedRuntime::_ICmiss_at[SharedRuntime::maxICmiss_count];
 184 
 185 
 186 void SharedRuntime::trace_ic_miss(address at) {
 187   for (int i = 0; i < _ICmiss_index; i++) {
 188     if (_ICmiss_at[i] == at) {
 189       _ICmiss_count[i]++;
 190       return;
 191     }
 192   }
 193   int index = _ICmiss_index++;
 194   if (_ICmiss_index >= maxICmiss_count) _ICmiss_index = maxICmiss_count - 1;
 195   _ICmiss_at[index] = at;
 196   _ICmiss_count[index] = 1;
 197 }
 198 
 199 void SharedRuntime::print_ic_miss_histogram() {
 200   if (ICMissHistogram) {
 201     tty->print_cr("IC Miss Histogram:");
 202     int tot_misses = 0;
 203     for (int i = 0; i < _ICmiss_index; i++) {
 204       tty->print_cr("  at: " INTPTR_FORMAT "  nof: %d", p2i(_ICmiss_at[i]), _ICmiss_count[i]);
 205       tot_misses += _ICmiss_count[i];
 206     }
 207     tty->print_cr("Total IC misses: %7d", tot_misses);
 208   }
 209 }
 210 #endif // PRODUCT
 211 
 212 
 213 JRT_LEAF(jlong, SharedRuntime::lmul(jlong y, jlong x))
 214   return x * y;
 215 JRT_END
 216 
 217 
 218 JRT_LEAF(jlong, SharedRuntime::ldiv(jlong y, jlong x))
 219   if (x == min_jlong && y == CONST64(-1)) {
 220     return x;
 221   } else {
 222     return x / y;
 223   }
 224 JRT_END
 225 
 226 
 227 JRT_LEAF(jlong, SharedRuntime::lrem(jlong y, jlong x))
 228   if (x == min_jlong && y == CONST64(-1)) {
 229     return 0;
 230   } else {
 231     return x % y;
 232   }
 233 JRT_END
 234 
 235 
 236 #ifdef _WIN64
 237 const juint  float_sign_mask  = 0x7FFFFFFF;
 238 const juint  float_infinity   = 0x7F800000;
 239 const julong double_sign_mask = CONST64(0x7FFFFFFFFFFFFFFF);
 240 const julong double_infinity  = CONST64(0x7FF0000000000000);
 241 #endif
 242 
 243 #if !defined(X86)
 244 JRT_LEAF(jfloat, SharedRuntime::frem(jfloat x, jfloat y))
 245 #ifdef _WIN64
 246   // 64-bit Windows on amd64 returns the wrong values for
 247   // infinity operands.
 248   juint xbits = PrimitiveConversions::cast<juint>(x);
 249   juint ybits = PrimitiveConversions::cast<juint>(y);
 250   // x Mod Infinity == x unless x is infinity
 251   if (((xbits & float_sign_mask) != float_infinity) &&
 252        ((ybits & float_sign_mask) == float_infinity) ) {
 253     return x;
 254   }
 255   return ((jfloat)fmod_winx64((double)x, (double)y));
 256 #else
 257   return ((jfloat)fmod((double)x,(double)y));
 258 #endif
 259 JRT_END
 260 
 261 JRT_LEAF(jdouble, SharedRuntime::drem(jdouble x, jdouble y))
 262 #ifdef _WIN64
 263   julong xbits = PrimitiveConversions::cast<julong>(x);
 264   julong ybits = PrimitiveConversions::cast<julong>(y);
 265   // x Mod Infinity == x unless x is infinity
 266   if (((xbits & double_sign_mask) != double_infinity) &&
 267        ((ybits & double_sign_mask) == double_infinity) ) {
 268     return x;
 269   }
 270   return ((jdouble)fmod_winx64((double)x, (double)y));
 271 #else
 272   return ((jdouble)fmod((double)x,(double)y));
 273 #endif
 274 JRT_END
 275 #endif // !X86
 276 
 277 JRT_LEAF(jfloat, SharedRuntime::i2f(jint x))
 278   return (jfloat)x;
 279 JRT_END
 280 
 281 #ifdef __SOFTFP__
 282 JRT_LEAF(jfloat, SharedRuntime::fadd(jfloat x, jfloat y))
 283   return x + y;
 284 JRT_END
 285 
 286 JRT_LEAF(jfloat, SharedRuntime::fsub(jfloat x, jfloat y))
 287   return x - y;
 288 JRT_END
 289 
 290 JRT_LEAF(jfloat, SharedRuntime::fmul(jfloat x, jfloat y))
 291   return x * y;
 292 JRT_END
 293 
 294 JRT_LEAF(jfloat, SharedRuntime::fdiv(jfloat x, jfloat y))
 295   return x / y;
 296 JRT_END
 297 
 298 JRT_LEAF(jdouble, SharedRuntime::dadd(jdouble x, jdouble y))
 299   return x + y;
 300 JRT_END
 301 
 302 JRT_LEAF(jdouble, SharedRuntime::dsub(jdouble x, jdouble y))
 303   return x - y;
 304 JRT_END
 305 
 306 JRT_LEAF(jdouble, SharedRuntime::dmul(jdouble x, jdouble y))
 307   return x * y;
 308 JRT_END
 309 
 310 JRT_LEAF(jdouble, SharedRuntime::ddiv(jdouble x, jdouble y))
 311   return x / y;
 312 JRT_END
 313 
 314 JRT_LEAF(jdouble, SharedRuntime::i2d(jint x))
 315   return (jdouble)x;
 316 JRT_END
 317 
 318 JRT_LEAF(jdouble, SharedRuntime::f2d(jfloat x))
 319   return (jdouble)x;
 320 JRT_END
 321 
 322 JRT_LEAF(int,  SharedRuntime::fcmpl(float x, float y))
 323   return x>y ? 1 : (x==y ? 0 : -1);  /* x<y or is_nan*/
 324 JRT_END
 325 
 326 JRT_LEAF(int,  SharedRuntime::fcmpg(float x, float y))
 327   return x<y ? -1 : (x==y ? 0 : 1);  /* x>y or is_nan */
 328 JRT_END
 329 
 330 JRT_LEAF(int,  SharedRuntime::dcmpl(double x, double y))
 331   return x>y ? 1 : (x==y ? 0 : -1); /* x<y or is_nan */
 332 JRT_END
 333 
 334 JRT_LEAF(int,  SharedRuntime::dcmpg(double x, double y))
 335   return x<y ? -1 : (x==y ? 0 : 1);  /* x>y or is_nan */
 336 JRT_END
 337 
 338 // Functions to return the opposite of the aeabi functions for nan.
 339 JRT_LEAF(int, SharedRuntime::unordered_fcmplt(float x, float y))
 340   return (x < y) ? 1 : ((g_isnan(x) || g_isnan(y)) ? 1 : 0);
 341 JRT_END
 342 
 343 JRT_LEAF(int, SharedRuntime::unordered_dcmplt(double x, double y))
 344   return (x < y) ? 1 : ((g_isnan(x) || g_isnan(y)) ? 1 : 0);
 345 JRT_END
 346 
 347 JRT_LEAF(int, SharedRuntime::unordered_fcmple(float x, float y))
 348   return (x <= y) ? 1 : ((g_isnan(x) || g_isnan(y)) ? 1 : 0);
 349 JRT_END
 350 
 351 JRT_LEAF(int, SharedRuntime::unordered_dcmple(double x, double y))
 352   return (x <= y) ? 1 : ((g_isnan(x) || g_isnan(y)) ? 1 : 0);
 353 JRT_END
 354 
 355 JRT_LEAF(int, SharedRuntime::unordered_fcmpge(float x, float y))
 356   return (x >= y) ? 1 : ((g_isnan(x) || g_isnan(y)) ? 1 : 0);
 357 JRT_END
 358 
 359 JRT_LEAF(int, SharedRuntime::unordered_dcmpge(double x, double y))
 360   return (x >= y) ? 1 : ((g_isnan(x) || g_isnan(y)) ? 1 : 0);
 361 JRT_END
 362 
 363 JRT_LEAF(int, SharedRuntime::unordered_fcmpgt(float x, float y))
 364   return (x > y) ? 1 : ((g_isnan(x) || g_isnan(y)) ? 1 : 0);
 365 JRT_END
 366 
 367 JRT_LEAF(int, SharedRuntime::unordered_dcmpgt(double x, double y))
 368   return (x > y) ? 1 : ((g_isnan(x) || g_isnan(y)) ? 1 : 0);
 369 JRT_END
 370 
 371 // Intrinsics make gcc generate code for these.
 372 float  SharedRuntime::fneg(float f)   {
 373   return -f;
 374 }
 375 
 376 double SharedRuntime::dneg(double f)  {
 377   return -f;
 378 }
 379 
 380 #endif // __SOFTFP__
 381 
 382 #if defined(__SOFTFP__) || defined(E500V2)
 383 // Intrinsics make gcc generate code for these.
 384 double SharedRuntime::dabs(double f)  {
 385   return (f <= (double)0.0) ? (double)0.0 - f : f;
 386 }
 387 
 388 #endif
 389 
 390 #if defined(__SOFTFP__) || defined(PPC)
 391 double SharedRuntime::dsqrt(double f) {
 392   return sqrt(f);
 393 }
 394 #endif
 395 
 396 JRT_LEAF(jint, SharedRuntime::f2i(jfloat  x))
 397   if (g_isnan(x))
 398     return 0;
 399   if (x >= (jfloat) max_jint)
 400     return max_jint;
 401   if (x <= (jfloat) min_jint)
 402     return min_jint;
 403   return (jint) x;
 404 JRT_END
 405 
 406 
 407 JRT_LEAF(jlong, SharedRuntime::f2l(jfloat  x))
 408   if (g_isnan(x))
 409     return 0;
 410   if (x >= (jfloat) max_jlong)
 411     return max_jlong;
 412   if (x <= (jfloat) min_jlong)
 413     return min_jlong;
 414   return (jlong) x;
 415 JRT_END
 416 
 417 
 418 JRT_LEAF(jint, SharedRuntime::d2i(jdouble x))
 419   if (g_isnan(x))
 420     return 0;
 421   if (x >= (jdouble) max_jint)
 422     return max_jint;
 423   if (x <= (jdouble) min_jint)
 424     return min_jint;
 425   return (jint) x;
 426 JRT_END
 427 
 428 
 429 JRT_LEAF(jlong, SharedRuntime::d2l(jdouble x))
 430   if (g_isnan(x))
 431     return 0;
 432   if (x >= (jdouble) max_jlong)
 433     return max_jlong;
 434   if (x <= (jdouble) min_jlong)
 435     return min_jlong;
 436   return (jlong) x;
 437 JRT_END
 438 
 439 
 440 JRT_LEAF(jfloat, SharedRuntime::d2f(jdouble x))
 441   return (jfloat)x;
 442 JRT_END
 443 
 444 
 445 JRT_LEAF(jfloat, SharedRuntime::l2f(jlong x))
 446   return (jfloat)x;
 447 JRT_END
 448 
 449 
 450 JRT_LEAF(jdouble, SharedRuntime::l2d(jlong x))
 451   return (jdouble)x;
 452 JRT_END
 453 
 454 
 455 // Exception handling across interpreter/compiler boundaries
 456 //
 457 // exception_handler_for_return_address(...) returns the continuation address.
 458 // The continuation address is the entry point of the exception handler of the
 459 // previous frame depending on the return address.
 460 
 461 address SharedRuntime::raw_exception_handler_for_return_address(JavaThread* current, address return_address) {
 462   // Note: This is called when we have unwound the frame of the callee that did
 463   // throw an exception. So far, no check has been performed by the StackWatermarkSet.
 464   // Notably, the stack is not walkable at this point, and hence the check must
 465   // be deferred until later. Specifically, any of the handlers returned here in
 466   // this function, will get dispatched to, and call deferred checks to
 467   // StackWatermarkSet::after_unwind at a point where the stack is walkable.
 468   assert(frame::verify_return_pc(return_address), "must be a return address: " INTPTR_FORMAT, p2i(return_address));
 469   assert(current->frames_to_pop_failed_realloc() == 0 || Interpreter::contains(return_address), "missed frames to pop?");
 470 
 471   // Reset method handle flag.
 472   current->set_is_method_handle_return(false);
 473 
 474 #if INCLUDE_JVMCI
 475   // JVMCI's ExceptionHandlerStub expects the thread local exception PC to be clear
 476   // and other exception handler continuations do not read it
 477   current->set_exception_pc(nullptr);
 478 #endif // INCLUDE_JVMCI
 479 
 480   if (Continuation::is_return_barrier_entry(return_address)) {
 481     return StubRoutines::cont_returnBarrierExc();
 482   }
 483 
 484   // write lock needed because we might update the pc desc cache via PcDescCache::add_pc_desc
 485   MACOS_AARCH64_ONLY(ThreadWXEnable wx(WXWrite, current));
 486 
 487   // The fastest case first
 488   CodeBlob* blob = CodeCache::find_blob(return_address);
 489   CompiledMethod* nm = (blob != nullptr) ? blob->as_compiled_method_or_null() : nullptr;
 490   if (nm != nullptr) {
 491     // Set flag if return address is a method handle call site.
 492     current->set_is_method_handle_return(nm->is_method_handle_return(return_address));
 493     // native nmethods don't have exception handlers
 494     assert(!nm->is_native_method() || nm->method()->is_continuation_enter_intrinsic(), "no exception handler");
 495     assert(nm->header_begin() != nm->exception_begin(), "no exception handler");
 496     if (nm->is_deopt_pc(return_address)) {
 497       // If we come here because of a stack overflow, the stack may be
 498       // unguarded. Reguard the stack otherwise if we return to the
 499       // deopt blob and the stack bang causes a stack overflow we
 500       // crash.
 501       StackOverflow* overflow_state = current->stack_overflow_state();
 502       bool guard_pages_enabled = overflow_state->reguard_stack_if_needed();
 503       if (overflow_state->reserved_stack_activation() != current->stack_base()) {
 504         overflow_state->set_reserved_stack_activation(current->stack_base());
 505       }
 506       assert(guard_pages_enabled, "stack banging in deopt blob may cause crash");
 507       // The deferred StackWatermarkSet::after_unwind check will be performed in
 508       // Deoptimization::fetch_unroll_info (with exec_mode == Unpack_exception)
 509       return SharedRuntime::deopt_blob()->unpack_with_exception();
 510     } else {
 511       // The deferred StackWatermarkSet::after_unwind check will be performed in
 512       // * OptoRuntime::handle_exception_C_helper for C2 code
 513       // * exception_handler_for_pc_helper via Runtime1::handle_exception_from_callee_id for C1 code
 514       return nm->exception_begin();
 515     }
 516   }
 517 
 518   // Entry code
 519   if (StubRoutines::returns_to_call_stub(return_address)) {
 520     // The deferred StackWatermarkSet::after_unwind check will be performed in
 521     // JavaCallWrapper::~JavaCallWrapper
 522     return StubRoutines::catch_exception_entry();
 523   }
 524   if (blob != nullptr && blob->is_upcall_stub()) {
 525     return StubRoutines::upcall_stub_exception_handler();
 526   }
 527   // Interpreted code
 528   if (Interpreter::contains(return_address)) {
 529     // The deferred StackWatermarkSet::after_unwind check will be performed in
 530     // InterpreterRuntime::exception_handler_for_exception
 531     return Interpreter::rethrow_exception_entry();
 532   }
 533 
 534   guarantee(blob == nullptr || !blob->is_runtime_stub(), "caller should have skipped stub");
 535   guarantee(!VtableStubs::contains(return_address), "null exceptions in vtables should have been handled already!");
 536 
 537 #ifndef PRODUCT
 538   { ResourceMark rm;
 539     tty->print_cr("No exception handler found for exception at " INTPTR_FORMAT " - potential problems:", p2i(return_address));
 540     os::print_location(tty, (intptr_t)return_address);
 541     tty->print_cr("a) exception happened in (new?) code stubs/buffers that is not handled here");
 542     tty->print_cr("b) other problem");
 543   }
 544 #endif // PRODUCT
 545 
 546   ShouldNotReachHere();
 547   return nullptr;
 548 }
 549 
 550 
 551 JRT_LEAF(address, SharedRuntime::exception_handler_for_return_address(JavaThread* current, address return_address))
 552   return raw_exception_handler_for_return_address(current, return_address);
 553 JRT_END
 554 
 555 
 556 address SharedRuntime::get_poll_stub(address pc) {
 557   address stub;
 558   // Look up the code blob
 559   CodeBlob *cb = CodeCache::find_blob(pc);
 560 
 561   // Should be an nmethod
 562   guarantee(cb != nullptr && cb->is_compiled(), "safepoint polling: pc must refer to an nmethod");
 563 
 564   // Look up the relocation information
 565   assert(((CompiledMethod*)cb)->is_at_poll_or_poll_return(pc),
 566       "safepoint polling: type must be poll at pc " INTPTR_FORMAT, p2i(pc));
 567 
 568 #ifdef ASSERT
 569   if (!((NativeInstruction*)pc)->is_safepoint_poll()) {
 570     tty->print_cr("bad pc: " PTR_FORMAT, p2i(pc));
 571     Disassembler::decode(cb);
 572     fatal("Only polling locations are used for safepoint");
 573   }
 574 #endif
 575 
 576   bool at_poll_return = ((CompiledMethod*)cb)->is_at_poll_return(pc);
 577   bool has_wide_vectors = ((CompiledMethod*)cb)->has_wide_vectors();
 578   if (at_poll_return) {
 579     assert(SharedRuntime::polling_page_return_handler_blob() != nullptr,
 580            "polling page return stub not created yet");
 581     stub = SharedRuntime::polling_page_return_handler_blob()->entry_point();
 582   } else if (has_wide_vectors) {
 583     assert(SharedRuntime::polling_page_vectors_safepoint_handler_blob() != nullptr,
 584            "polling page vectors safepoint stub not created yet");
 585     stub = SharedRuntime::polling_page_vectors_safepoint_handler_blob()->entry_point();
 586   } else {
 587     assert(SharedRuntime::polling_page_safepoint_handler_blob() != nullptr,
 588            "polling page safepoint stub not created yet");
 589     stub = SharedRuntime::polling_page_safepoint_handler_blob()->entry_point();
 590   }
 591   log_debug(safepoint)("... found polling page %s exception at pc = "
 592                        INTPTR_FORMAT ", stub =" INTPTR_FORMAT,
 593                        at_poll_return ? "return" : "loop",
 594                        (intptr_t)pc, (intptr_t)stub);
 595   return stub;
 596 }
 597 
 598 void SharedRuntime::throw_and_post_jvmti_exception(JavaThread* current, Handle h_exception) {
 599   if (JvmtiExport::can_post_on_exceptions()) {
 600     vframeStream vfst(current, true);
 601     methodHandle method = methodHandle(current, vfst.method());
 602     address bcp = method()->bcp_from(vfst.bci());
 603     JvmtiExport::post_exception_throw(current, method(), bcp, h_exception());
 604   }
 605 
 606 #if INCLUDE_JVMCI
 607   if (EnableJVMCI && UseJVMCICompiler) {
 608     vframeStream vfst(current, true);
 609     methodHandle method = methodHandle(current, vfst.method());
 610     int bci = vfst.bci();
 611     MethodData* trap_mdo = method->method_data();
 612     if (trap_mdo != nullptr) {
 613       // Set exception_seen if the exceptional bytecode is an invoke
 614       Bytecode_invoke call = Bytecode_invoke_check(method, bci);
 615       if (call.is_valid()) {
 616         ResourceMark rm(current);
 617 
 618         // Lock to read ProfileData, and ensure lock is not broken by a safepoint
 619         MutexLocker ml(trap_mdo->extra_data_lock(), Mutex::_no_safepoint_check_flag);
 620 
 621         ProfileData* pdata = trap_mdo->allocate_bci_to_data(bci, nullptr);
 622         if (pdata != nullptr && pdata->is_BitData()) {
 623           BitData* bit_data = (BitData*) pdata;
 624           bit_data->set_exception_seen();
 625         }
 626       }
 627     }
 628   }
 629 #endif
 630 
 631   Exceptions::_throw(current, __FILE__, __LINE__, h_exception);
 632 }
 633 
 634 void SharedRuntime::throw_and_post_jvmti_exception(JavaThread* current, Symbol* name, const char *message) {
 635   Handle h_exception = Exceptions::new_exception(current, name, message);
 636   throw_and_post_jvmti_exception(current, h_exception);
 637 }
 638 
 639 #if INCLUDE_JVMTI
 640 JRT_ENTRY(void, SharedRuntime::notify_jvmti_vthread_start(oopDesc* vt, jboolean hide, JavaThread* current))
 641   assert(hide == JNI_FALSE, "must be VTMS transition finish");
 642   jobject vthread = JNIHandles::make_local(const_cast<oopDesc*>(vt));
 643   JvmtiVTMSTransitionDisabler::VTMS_vthread_start(vthread);
 644   JNIHandles::destroy_local(vthread);
 645 JRT_END
 646 
 647 JRT_ENTRY(void, SharedRuntime::notify_jvmti_vthread_end(oopDesc* vt, jboolean hide, JavaThread* current))
 648   assert(hide == JNI_TRUE, "must be VTMS transition start");
 649   jobject vthread = JNIHandles::make_local(const_cast<oopDesc*>(vt));
 650   JvmtiVTMSTransitionDisabler::VTMS_vthread_end(vthread);
 651   JNIHandles::destroy_local(vthread);
 652 JRT_END
 653 
 654 JRT_ENTRY(void, SharedRuntime::notify_jvmti_vthread_mount(oopDesc* vt, jboolean hide, JavaThread* current))
 655   jobject vthread = JNIHandles::make_local(const_cast<oopDesc*>(vt));
 656   JvmtiVTMSTransitionDisabler::VTMS_vthread_mount(vthread, hide);
 657   JNIHandles::destroy_local(vthread);
 658 JRT_END
 659 
 660 JRT_ENTRY(void, SharedRuntime::notify_jvmti_vthread_unmount(oopDesc* vt, jboolean hide, JavaThread* current))
 661   jobject vthread = JNIHandles::make_local(const_cast<oopDesc*>(vt));
 662   JvmtiVTMSTransitionDisabler::VTMS_vthread_unmount(vthread, hide);
 663   JNIHandles::destroy_local(vthread);
 664 JRT_END
 665 #endif // INCLUDE_JVMTI
 666 
 667 // The interpreter code to call this tracing function is only
 668 // called/generated when UL is on for redefine, class and has the right level
 669 // and tags. Since obsolete methods are never compiled, we don't have
 670 // to modify the compilers to generate calls to this function.
 671 //
 672 JRT_LEAF(int, SharedRuntime::rc_trace_method_entry(
 673     JavaThread* thread, Method* method))
 674   if (method->is_obsolete()) {
 675     // We are calling an obsolete method, but this is not necessarily
 676     // an error. Our method could have been redefined just after we
 677     // fetched the Method* from the constant pool.
 678     ResourceMark rm;
 679     log_trace(redefine, class, obsolete)("calling obsolete method '%s'", method->name_and_sig_as_C_string());
 680   }
 681   return 0;
 682 JRT_END
 683 
 684 // ret_pc points into caller; we are returning caller's exception handler
 685 // for given exception
 686 // Note that the implementation of this method assumes it's only called when an exception has actually occured
 687 address SharedRuntime::compute_compiled_exc_handler(CompiledMethod* cm, address ret_pc, Handle& exception,
 688                                                     bool force_unwind, bool top_frame_only, bool& recursive_exception_occurred) {
 689   assert(cm != nullptr, "must exist");
 690   ResourceMark rm;
 691 
 692 #if INCLUDE_JVMCI
 693   if (cm->is_compiled_by_jvmci()) {
 694     // lookup exception handler for this pc
 695     int catch_pco = pointer_delta_as_int(ret_pc, cm->code_begin());
 696     ExceptionHandlerTable table(cm);
 697     HandlerTableEntry *t = table.entry_for(catch_pco, -1, 0);
 698     if (t != nullptr) {
 699       return cm->code_begin() + t->pco();
 700     } else {
 701       return Deoptimization::deoptimize_for_missing_exception_handler(cm);
 702     }
 703   }
 704 #endif // INCLUDE_JVMCI
 705 
 706   nmethod* nm = cm->as_nmethod();
 707   ScopeDesc* sd = nm->scope_desc_at(ret_pc);
 708   // determine handler bci, if any
 709   EXCEPTION_MARK;
 710 
 711   int handler_bci = -1;
 712   int scope_depth = 0;
 713   if (!force_unwind) {
 714     int bci = sd->bci();
 715     bool recursive_exception = false;
 716     do {
 717       bool skip_scope_increment = false;
 718       // exception handler lookup
 719       Klass* ek = exception->klass();
 720       methodHandle mh(THREAD, sd->method());
 721       handler_bci = Method::fast_exception_handler_bci_for(mh, ek, bci, THREAD);
 722       if (HAS_PENDING_EXCEPTION) {
 723         recursive_exception = true;
 724         // We threw an exception while trying to find the exception handler.
 725         // Transfer the new exception to the exception handle which will
 726         // be set into thread local storage, and do another lookup for an
 727         // exception handler for this exception, this time starting at the
 728         // BCI of the exception handler which caused the exception to be
 729         // thrown (bugs 4307310 and 4546590). Set "exception" reference
 730         // argument to ensure that the correct exception is thrown (4870175).
 731         recursive_exception_occurred = true;
 732         exception = Handle(THREAD, PENDING_EXCEPTION);
 733         CLEAR_PENDING_EXCEPTION;
 734         if (handler_bci >= 0) {
 735           bci = handler_bci;
 736           handler_bci = -1;
 737           skip_scope_increment = true;
 738         }
 739       }
 740       else {
 741         recursive_exception = false;
 742       }
 743       if (!top_frame_only && handler_bci < 0 && !skip_scope_increment) {
 744         sd = sd->sender();
 745         if (sd != nullptr) {
 746           bci = sd->bci();
 747         }
 748         ++scope_depth;
 749       }
 750     } while (recursive_exception || (!top_frame_only && handler_bci < 0 && sd != nullptr));
 751   }
 752 
 753   // found handling method => lookup exception handler
 754   int catch_pco = pointer_delta_as_int(ret_pc, nm->code_begin());
 755 
 756   ExceptionHandlerTable table(nm);
 757   HandlerTableEntry *t = table.entry_for(catch_pco, handler_bci, scope_depth);
 758   if (t == nullptr && (nm->is_compiled_by_c1() || handler_bci != -1)) {
 759     // Allow abbreviated catch tables.  The idea is to allow a method
 760     // to materialize its exceptions without committing to the exact
 761     // routing of exceptions.  In particular this is needed for adding
 762     // a synthetic handler to unlock monitors when inlining
 763     // synchronized methods since the unlock path isn't represented in
 764     // the bytecodes.
 765     t = table.entry_for(catch_pco, -1, 0);
 766   }
 767 
 768 #ifdef COMPILER1
 769   if (t == nullptr && nm->is_compiled_by_c1()) {
 770     assert(nm->unwind_handler_begin() != nullptr, "");
 771     return nm->unwind_handler_begin();
 772   }
 773 #endif
 774 
 775   if (t == nullptr) {
 776     ttyLocker ttyl;
 777     tty->print_cr("MISSING EXCEPTION HANDLER for pc " INTPTR_FORMAT " and handler bci %d, catch_pco: %d", p2i(ret_pc), handler_bci, catch_pco);
 778     tty->print_cr("   Exception:");
 779     exception->print();
 780     tty->cr();
 781     tty->print_cr(" Compiled exception table :");
 782     table.print();
 783     nm->print();
 784     nm->print_code();
 785     guarantee(false, "missing exception handler");
 786     return nullptr;
 787   }
 788 
 789   if (handler_bci != -1) { // did we find a handler in this method?
 790     sd->method()->set_exception_handler_entered(handler_bci); // profile
 791   }
 792   return nm->code_begin() + t->pco();
 793 }
 794 
 795 JRT_ENTRY(void, SharedRuntime::throw_AbstractMethodError(JavaThread* current))
 796   // These errors occur only at call sites
 797   throw_and_post_jvmti_exception(current, vmSymbols::java_lang_AbstractMethodError());
 798 JRT_END
 799 
 800 JRT_ENTRY(void, SharedRuntime::throw_IncompatibleClassChangeError(JavaThread* current))
 801   // These errors occur only at call sites
 802   throw_and_post_jvmti_exception(current, vmSymbols::java_lang_IncompatibleClassChangeError(), "vtable stub");
 803 JRT_END
 804 
 805 JRT_ENTRY(void, SharedRuntime::throw_ArithmeticException(JavaThread* current))
 806   throw_and_post_jvmti_exception(current, vmSymbols::java_lang_ArithmeticException(), "/ by zero");
 807 JRT_END
 808 
 809 JRT_ENTRY(void, SharedRuntime::throw_NullPointerException(JavaThread* current))
 810   throw_and_post_jvmti_exception(current, vmSymbols::java_lang_NullPointerException(), nullptr);
 811 JRT_END
 812 
 813 JRT_ENTRY(void, SharedRuntime::throw_NullPointerException_at_call(JavaThread* current))
 814   // This entry point is effectively only used for NullPointerExceptions which occur at inline
 815   // cache sites (when the callee activation is not yet set up) so we are at a call site
 816   throw_and_post_jvmti_exception(current, vmSymbols::java_lang_NullPointerException(), nullptr);
 817 JRT_END
 818 
 819 JRT_ENTRY(void, SharedRuntime::throw_StackOverflowError(JavaThread* current))
 820   throw_StackOverflowError_common(current, false);
 821 JRT_END
 822 
 823 JRT_ENTRY(void, SharedRuntime::throw_delayed_StackOverflowError(JavaThread* current))
 824   throw_StackOverflowError_common(current, true);
 825 JRT_END
 826 
 827 void SharedRuntime::throw_StackOverflowError_common(JavaThread* current, bool delayed) {
 828   // We avoid using the normal exception construction in this case because
 829   // it performs an upcall to Java, and we're already out of stack space.
 830   JavaThread* THREAD = current; // For exception macros.
 831   Klass* k = vmClasses::StackOverflowError_klass();
 832   oop exception_oop = InstanceKlass::cast(k)->allocate_instance(CHECK);
 833   if (delayed) {
 834     java_lang_Throwable::set_message(exception_oop,
 835                                      Universe::delayed_stack_overflow_error_message());
 836   }
 837   Handle exception (current, exception_oop);
 838   if (StackTraceInThrowable) {
 839     java_lang_Throwable::fill_in_stack_trace(exception);
 840   }
 841   // Remove the ScopedValue bindings in case we got a
 842   // StackOverflowError while we were trying to remove ScopedValue
 843   // bindings.
 844   current->clear_scopedValueBindings();
 845   // Increment counter for hs_err file reporting
 846   Atomic::inc(&Exceptions::_stack_overflow_errors);
 847   throw_and_post_jvmti_exception(current, exception);
 848 }
 849 
 850 address SharedRuntime::continuation_for_implicit_exception(JavaThread* current,
 851                                                            address pc,
 852                                                            ImplicitExceptionKind exception_kind)
 853 {
 854   address target_pc = nullptr;
 855 
 856   if (Interpreter::contains(pc)) {
 857     switch (exception_kind) {
 858       case IMPLICIT_NULL:           return Interpreter::throw_NullPointerException_entry();
 859       case IMPLICIT_DIVIDE_BY_ZERO: return Interpreter::throw_ArithmeticException_entry();
 860       case STACK_OVERFLOW:          return Interpreter::throw_StackOverflowError_entry();
 861       default:                      ShouldNotReachHere();
 862     }
 863   } else {
 864     switch (exception_kind) {
 865       case STACK_OVERFLOW: {
 866         // Stack overflow only occurs upon frame setup; the callee is
 867         // going to be unwound. Dispatch to a shared runtime stub
 868         // which will cause the StackOverflowError to be fabricated
 869         // and processed.
 870         // Stack overflow should never occur during deoptimization:
 871         // the compiled method bangs the stack by as much as the
 872         // interpreter would need in case of a deoptimization. The
 873         // deoptimization blob and uncommon trap blob bang the stack
 874         // in a debug VM to verify the correctness of the compiled
 875         // method stack banging.
 876         assert(current->deopt_mark() == nullptr, "no stack overflow from deopt blob/uncommon trap");
 877         Events::log_exception(current, "StackOverflowError at " INTPTR_FORMAT, p2i(pc));
 878         return StubRoutines::throw_StackOverflowError_entry();
 879       }
 880 
 881       case IMPLICIT_NULL: {
 882         if (VtableStubs::contains(pc)) {
 883           // We haven't yet entered the callee frame. Fabricate an
 884           // exception and begin dispatching it in the caller. Since
 885           // the caller was at a call site, it's safe to destroy all
 886           // caller-saved registers, as these entry points do.
 887           VtableStub* vt_stub = VtableStubs::stub_containing(pc);
 888 
 889           // If vt_stub is null, then return null to signal handler to report the SEGV error.
 890           if (vt_stub == nullptr) return nullptr;
 891 
 892           if (vt_stub->is_abstract_method_error(pc)) {
 893             assert(!vt_stub->is_vtable_stub(), "should never see AbstractMethodErrors from vtable-type VtableStubs");
 894             Events::log_exception(current, "AbstractMethodError at " INTPTR_FORMAT, p2i(pc));
 895             // Instead of throwing the abstract method error here directly, we re-resolve
 896             // and will throw the AbstractMethodError during resolve. As a result, we'll
 897             // get a more detailed error message.
 898             return SharedRuntime::get_handle_wrong_method_stub();
 899           } else {
 900             Events::log_exception(current, "NullPointerException at vtable entry " INTPTR_FORMAT, p2i(pc));
 901             // Assert that the signal comes from the expected location in stub code.
 902             assert(vt_stub->is_null_pointer_exception(pc),
 903                    "obtained signal from unexpected location in stub code");
 904             return StubRoutines::throw_NullPointerException_at_call_entry();
 905           }
 906         } else {
 907           CodeBlob* cb = CodeCache::find_blob(pc);
 908 
 909           // If code blob is null, then return null to signal handler to report the SEGV error.
 910           if (cb == nullptr) return nullptr;
 911 
 912           // Exception happened in CodeCache. Must be either:
 913           // 1. Inline-cache check in C2I handler blob,
 914           // 2. Inline-cache check in nmethod, or
 915           // 3. Implicit null exception in nmethod
 916 
 917           if (!cb->is_compiled()) {
 918             bool is_in_blob = cb->is_adapter_blob() || cb->is_method_handles_adapter_blob();
 919             if (!is_in_blob) {
 920               // Allow normal crash reporting to handle this
 921               return nullptr;
 922             }
 923             Events::log_exception(current, "NullPointerException in code blob at " INTPTR_FORMAT, p2i(pc));
 924             // There is no handler here, so we will simply unwind.
 925             return StubRoutines::throw_NullPointerException_at_call_entry();
 926           }
 927 
 928           // Otherwise, it's a compiled method.  Consult its exception handlers.
 929           CompiledMethod* cm = (CompiledMethod*)cb;
 930           if (cm->inlinecache_check_contains(pc)) {
 931             // exception happened inside inline-cache check code
 932             // => the nmethod is not yet active (i.e., the frame
 933             // is not set up yet) => use return address pushed by
 934             // caller => don't push another return address
 935             Events::log_exception(current, "NullPointerException in IC check " INTPTR_FORMAT, p2i(pc));
 936             return StubRoutines::throw_NullPointerException_at_call_entry();
 937           }
 938 
 939           if (cm->method()->is_method_handle_intrinsic()) {
 940             // exception happened inside MH dispatch code, similar to a vtable stub
 941             Events::log_exception(current, "NullPointerException in MH adapter " INTPTR_FORMAT, p2i(pc));
 942             return StubRoutines::throw_NullPointerException_at_call_entry();
 943           }
 944 
 945 #ifndef PRODUCT
 946           _implicit_null_throws++;
 947 #endif
 948           target_pc = cm->continuation_for_implicit_null_exception(pc);
 949           // If there's an unexpected fault, target_pc might be null,
 950           // in which case we want to fall through into the normal
 951           // error handling code.
 952         }
 953 
 954         break; // fall through
 955       }
 956 
 957 
 958       case IMPLICIT_DIVIDE_BY_ZERO: {
 959         CompiledMethod* cm = CodeCache::find_compiled(pc);
 960         guarantee(cm != nullptr, "must have containing compiled method for implicit division-by-zero exceptions");
 961 #ifndef PRODUCT
 962         _implicit_div0_throws++;
 963 #endif
 964         target_pc = cm->continuation_for_implicit_div0_exception(pc);
 965         // If there's an unexpected fault, target_pc might be null,
 966         // in which case we want to fall through into the normal
 967         // error handling code.
 968         break; // fall through
 969       }
 970 
 971       default: ShouldNotReachHere();
 972     }
 973 
 974     assert(exception_kind == IMPLICIT_NULL || exception_kind == IMPLICIT_DIVIDE_BY_ZERO, "wrong implicit exception kind");
 975 
 976     if (exception_kind == IMPLICIT_NULL) {
 977 #ifndef PRODUCT
 978       // for AbortVMOnException flag
 979       Exceptions::debug_check_abort("java.lang.NullPointerException");
 980 #endif //PRODUCT
 981       Events::log_exception(current, "Implicit null exception at " INTPTR_FORMAT " to " INTPTR_FORMAT, p2i(pc), p2i(target_pc));
 982     } else {
 983 #ifndef PRODUCT
 984       // for AbortVMOnException flag
 985       Exceptions::debug_check_abort("java.lang.ArithmeticException");
 986 #endif //PRODUCT
 987       Events::log_exception(current, "Implicit division by zero exception at " INTPTR_FORMAT " to " INTPTR_FORMAT, p2i(pc), p2i(target_pc));
 988     }
 989     return target_pc;
 990   }
 991 
 992   ShouldNotReachHere();
 993   return nullptr;
 994 }
 995 
 996 
 997 /**
 998  * Throws an java/lang/UnsatisfiedLinkError.  The address of this method is
 999  * installed in the native function entry of all native Java methods before
1000  * they get linked to their actual native methods.
1001  *
1002  * \note
1003  * This method actually never gets called!  The reason is because
1004  * the interpreter's native entries call NativeLookup::lookup() which
1005  * throws the exception when the lookup fails.  The exception is then
1006  * caught and forwarded on the return from NativeLookup::lookup() call
1007  * before the call to the native function.  This might change in the future.
1008  */
1009 JNI_ENTRY(void*, throw_unsatisfied_link_error(JNIEnv* env, ...))
1010 {
1011   // We return a bad value here to make sure that the exception is
1012   // forwarded before we look at the return value.
1013   THROW_(vmSymbols::java_lang_UnsatisfiedLinkError(), (void*)badAddress);
1014 }
1015 JNI_END
1016 
1017 address SharedRuntime::native_method_throw_unsatisfied_link_error_entry() {
1018   return CAST_FROM_FN_PTR(address, &throw_unsatisfied_link_error);
1019 }
1020 
1021 JRT_ENTRY_NO_ASYNC(void, SharedRuntime::register_finalizer(JavaThread* current, oopDesc* obj))
1022 #if INCLUDE_JVMCI
1023   if (!obj->klass()->has_finalizer()) {
1024     return;
1025   }
1026 #endif // INCLUDE_JVMCI
1027   assert(oopDesc::is_oop(obj), "must be a valid oop");
1028   assert(obj->klass()->has_finalizer(), "shouldn't be here otherwise");
1029   InstanceKlass::register_finalizer(instanceOop(obj), CHECK);
1030 JRT_END
1031 
1032 jlong SharedRuntime::get_java_tid(JavaThread* thread) {
1033   assert(thread != nullptr, "No thread");
1034   if (thread == nullptr) {
1035     return 0;
1036   }
1037   guarantee(Thread::current() != thread || thread->is_oop_safe(),
1038             "current cannot touch oops after its GC barrier is detached.");
1039   oop obj = thread->threadObj();
1040   return (obj == nullptr) ? 0 : java_lang_Thread::thread_id(obj);
1041 }
1042 
1043 /**
1044  * This function ought to be a void function, but cannot be because
1045  * it gets turned into a tail-call on sparc, which runs into dtrace bug
1046  * 6254741.  Once that is fixed we can remove the dummy return value.
1047  */
1048 int SharedRuntime::dtrace_object_alloc(oopDesc* o) {
1049   return dtrace_object_alloc(JavaThread::current(), o, o->size());
1050 }
1051 
1052 int SharedRuntime::dtrace_object_alloc(JavaThread* thread, oopDesc* o) {
1053   return dtrace_object_alloc(thread, o, o->size());
1054 }
1055 
1056 int SharedRuntime::dtrace_object_alloc(JavaThread* thread, oopDesc* o, size_t size) {
1057   assert(DTraceAllocProbes, "wrong call");
1058   Klass* klass = o->klass();
1059   Symbol* name = klass->name();
1060   HOTSPOT_OBJECT_ALLOC(
1061                    get_java_tid(thread),
1062                    (char *) name->bytes(), name->utf8_length(), size * HeapWordSize);
1063   return 0;
1064 }
1065 
1066 JRT_LEAF(int, SharedRuntime::dtrace_method_entry(
1067     JavaThread* current, Method* method))
1068   assert(current == JavaThread::current(), "pre-condition");
1069 
1070   assert(DTraceMethodProbes, "wrong call");
1071   Symbol* kname = method->klass_name();
1072   Symbol* name = method->name();
1073   Symbol* sig = method->signature();
1074   HOTSPOT_METHOD_ENTRY(
1075       get_java_tid(current),
1076       (char *) kname->bytes(), kname->utf8_length(),
1077       (char *) name->bytes(), name->utf8_length(),
1078       (char *) sig->bytes(), sig->utf8_length());
1079   return 0;
1080 JRT_END
1081 
1082 JRT_LEAF(int, SharedRuntime::dtrace_method_exit(
1083     JavaThread* current, Method* method))
1084   assert(current == JavaThread::current(), "pre-condition");
1085   assert(DTraceMethodProbes, "wrong call");
1086   Symbol* kname = method->klass_name();
1087   Symbol* name = method->name();
1088   Symbol* sig = method->signature();
1089   HOTSPOT_METHOD_RETURN(
1090       get_java_tid(current),
1091       (char *) kname->bytes(), kname->utf8_length(),
1092       (char *) name->bytes(), name->utf8_length(),
1093       (char *) sig->bytes(), sig->utf8_length());
1094   return 0;
1095 JRT_END
1096 
1097 
1098 // Finds receiver, CallInfo (i.e. receiver method), and calling bytecode)
1099 // for a call current in progress, i.e., arguments has been pushed on stack
1100 // put callee has not been invoked yet.  Used by: resolve virtual/static,
1101 // vtable updates, etc.  Caller frame must be compiled.
1102 Handle SharedRuntime::find_callee_info(Bytecodes::Code& bc, CallInfo& callinfo, TRAPS) {
1103   JavaThread* current = THREAD;
1104   ResourceMark rm(current);
1105 
1106   // last java frame on stack (which includes native call frames)
1107   vframeStream vfst(current, true);  // Do not skip and javaCalls
1108 
1109   return find_callee_info_helper(vfst, bc, callinfo, THREAD);
1110 }
1111 
1112 Method* SharedRuntime::extract_attached_method(vframeStream& vfst) {
1113   CompiledMethod* caller = vfst.nm();
1114 
1115   address pc = vfst.frame_pc();
1116   { // Get call instruction under lock because another thread may be busy patching it.
1117     CompiledICLocker ic_locker(caller);
1118     return caller->attached_method_before_pc(pc);
1119   }
1120   return nullptr;
1121 }
1122 
1123 // Finds receiver, CallInfo (i.e. receiver method), and calling bytecode
1124 // for a call current in progress, i.e., arguments has been pushed on stack
1125 // but callee has not been invoked yet.  Caller frame must be compiled.
1126 Handle SharedRuntime::find_callee_info_helper(vframeStream& vfst, Bytecodes::Code& bc,
1127                                               CallInfo& callinfo, TRAPS) {
1128   Handle receiver;
1129   Handle nullHandle;  // create a handy null handle for exception returns
1130   JavaThread* current = THREAD;
1131 
1132   assert(!vfst.at_end(), "Java frame must exist");
1133 
1134   // Find caller and bci from vframe
1135   methodHandle caller(current, vfst.method());
1136   int          bci   = vfst.bci();
1137 
1138   if (caller->is_continuation_enter_intrinsic()) {
1139     bc = Bytecodes::_invokestatic;
1140     LinkResolver::resolve_continuation_enter(callinfo, CHECK_NH);
1141     return receiver;
1142   }
1143 
1144   Bytecode_invoke bytecode(caller, bci);
1145   int bytecode_index = bytecode.index();
1146   bc = bytecode.invoke_code();
1147 
1148   methodHandle attached_method(current, extract_attached_method(vfst));
1149   if (attached_method.not_null()) {
1150     Method* callee = bytecode.static_target(CHECK_NH);
1151     vmIntrinsics::ID id = callee->intrinsic_id();
1152     // When VM replaces MH.invokeBasic/linkTo* call with a direct/virtual call,
1153     // it attaches statically resolved method to the call site.
1154     if (MethodHandles::is_signature_polymorphic(id) &&
1155         MethodHandles::is_signature_polymorphic_intrinsic(id)) {
1156       bc = MethodHandles::signature_polymorphic_intrinsic_bytecode(id);
1157 
1158       // Adjust invocation mode according to the attached method.
1159       switch (bc) {
1160         case Bytecodes::_invokevirtual:
1161           if (attached_method->method_holder()->is_interface()) {
1162             bc = Bytecodes::_invokeinterface;
1163           }
1164           break;
1165         case Bytecodes::_invokeinterface:
1166           if (!attached_method->method_holder()->is_interface()) {
1167             bc = Bytecodes::_invokevirtual;
1168           }
1169           break;
1170         case Bytecodes::_invokehandle:
1171           if (!MethodHandles::is_signature_polymorphic_method(attached_method())) {
1172             bc = attached_method->is_static() ? Bytecodes::_invokestatic
1173                                               : Bytecodes::_invokevirtual;
1174           }
1175           break;
1176         default:
1177           break;
1178       }
1179     }
1180   }
1181 
1182   assert(bc != Bytecodes::_illegal, "not initialized");
1183 
1184   bool has_receiver = bc != Bytecodes::_invokestatic &&
1185                       bc != Bytecodes::_invokedynamic &&
1186                       bc != Bytecodes::_invokehandle;
1187 
1188   // Find receiver for non-static call
1189   if (has_receiver) {
1190     // This register map must be update since we need to find the receiver for
1191     // compiled frames. The receiver might be in a register.
1192     RegisterMap reg_map2(current,
1193                          RegisterMap::UpdateMap::include,
1194                          RegisterMap::ProcessFrames::include,
1195                          RegisterMap::WalkContinuation::skip);
1196     frame stubFrame   = current->last_frame();
1197     // Caller-frame is a compiled frame
1198     frame callerFrame = stubFrame.sender(&reg_map2);
1199 
1200     if (attached_method.is_null()) {
1201       Method* callee = bytecode.static_target(CHECK_NH);
1202       if (callee == nullptr) {
1203         THROW_(vmSymbols::java_lang_NoSuchMethodException(), nullHandle);
1204       }
1205     }
1206 
1207     // Retrieve from a compiled argument list
1208     receiver = Handle(current, callerFrame.retrieve_receiver(&reg_map2));
1209     assert(oopDesc::is_oop_or_null(receiver()), "");
1210 
1211     if (receiver.is_null()) {
1212       THROW_(vmSymbols::java_lang_NullPointerException(), nullHandle);
1213     }
1214   }
1215 
1216   // Resolve method
1217   if (attached_method.not_null()) {
1218     // Parameterized by attached method.
1219     LinkResolver::resolve_invoke(callinfo, receiver, attached_method, bc, CHECK_NH);
1220   } else {
1221     // Parameterized by bytecode.
1222     constantPoolHandle constants(current, caller->constants());
1223     LinkResolver::resolve_invoke(callinfo, receiver, constants, bytecode_index, bc, CHECK_NH);
1224   }
1225 
1226 #ifdef ASSERT
1227   // Check that the receiver klass is of the right subtype and that it is initialized for virtual calls
1228   if (has_receiver) {
1229     assert(receiver.not_null(), "should have thrown exception");
1230     Klass* receiver_klass = receiver->klass();
1231     Klass* rk = nullptr;
1232     if (attached_method.not_null()) {
1233       // In case there's resolved method attached, use its holder during the check.
1234       rk = attached_method->method_holder();
1235     } else {
1236       // Klass is already loaded.
1237       constantPoolHandle constants(current, caller->constants());
1238       rk = constants->klass_ref_at(bytecode_index, bc, CHECK_NH);
1239     }
1240     Klass* static_receiver_klass = rk;
1241     assert(receiver_klass->is_subtype_of(static_receiver_klass),
1242            "actual receiver must be subclass of static receiver klass");
1243     if (receiver_klass->is_instance_klass()) {
1244       if (InstanceKlass::cast(receiver_klass)->is_not_initialized()) {
1245         tty->print_cr("ERROR: Klass not yet initialized!!");
1246         receiver_klass->print();
1247       }
1248       assert(!InstanceKlass::cast(receiver_klass)->is_not_initialized(), "receiver_klass must be initialized");
1249     }
1250   }
1251 #endif
1252 
1253   return receiver;
1254 }
1255 
1256 methodHandle SharedRuntime::find_callee_method(TRAPS) {
1257   JavaThread* current = THREAD;
1258   ResourceMark rm(current);
1259   // We need first to check if any Java activations (compiled, interpreted)
1260   // exist on the stack since last JavaCall.  If not, we need
1261   // to get the target method from the JavaCall wrapper.
1262   vframeStream vfst(current, true);  // Do not skip any javaCalls
1263   methodHandle callee_method;
1264   if (vfst.at_end()) {
1265     // No Java frames were found on stack since we did the JavaCall.
1266     // Hence the stack can only contain an entry_frame.  We need to
1267     // find the target method from the stub frame.
1268     RegisterMap reg_map(current,
1269                         RegisterMap::UpdateMap::skip,
1270                         RegisterMap::ProcessFrames::include,
1271                         RegisterMap::WalkContinuation::skip);
1272     frame fr = current->last_frame();
1273     assert(fr.is_runtime_frame(), "must be a runtimeStub");
1274     fr = fr.sender(&reg_map);
1275     assert(fr.is_entry_frame(), "must be");
1276     // fr is now pointing to the entry frame.
1277     callee_method = methodHandle(current, fr.entry_frame_call_wrapper()->callee_method());
1278   } else {
1279     Bytecodes::Code bc;
1280     CallInfo callinfo;
1281     find_callee_info_helper(vfst, bc, callinfo, CHECK_(methodHandle()));
1282     callee_method = methodHandle(current, callinfo.selected_method());
1283   }
1284   assert(callee_method()->is_method(), "must be");
1285   return callee_method;
1286 }
1287 
1288 // Resolves a call.
1289 methodHandle SharedRuntime::resolve_helper(bool is_virtual, bool is_optimized, TRAPS) {
1290   JavaThread* current = THREAD;
1291   ResourceMark rm(current);
1292   RegisterMap cbl_map(current,
1293                       RegisterMap::UpdateMap::skip,
1294                       RegisterMap::ProcessFrames::include,
1295                       RegisterMap::WalkContinuation::skip);
1296   frame caller_frame = current->last_frame().sender(&cbl_map);
1297 
1298   CodeBlob* caller_cb = caller_frame.cb();
1299   guarantee(caller_cb != nullptr && caller_cb->is_compiled(), "must be called from compiled method");
1300   CompiledMethod* caller_nm = caller_cb->as_compiled_method();
1301 
1302   // determine call info & receiver
1303   // note: a) receiver is null for static calls
1304   //       b) an exception is thrown if receiver is null for non-static calls
1305   CallInfo call_info;
1306   Bytecodes::Code invoke_code = Bytecodes::_illegal;
1307   Handle receiver = find_callee_info(invoke_code, call_info, CHECK_(methodHandle()));
1308 
1309   NoSafepointVerifier nsv;
1310 
1311   methodHandle callee_method(current, call_info.selected_method());
1312 
1313   assert((!is_virtual && invoke_code == Bytecodes::_invokestatic ) ||
1314          (!is_virtual && invoke_code == Bytecodes::_invokespecial) ||
1315          (!is_virtual && invoke_code == Bytecodes::_invokehandle ) ||
1316          (!is_virtual && invoke_code == Bytecodes::_invokedynamic) ||
1317          ( is_virtual && invoke_code != Bytecodes::_invokestatic ), "inconsistent bytecode");
1318 
1319   assert(!caller_nm->is_unloading(), "It should not be unloading");
1320 
1321 #ifndef PRODUCT
1322   // tracing/debugging/statistics
1323   uint *addr = (is_optimized) ? (&_resolve_opt_virtual_ctr) :
1324                  (is_virtual) ? (&_resolve_virtual_ctr) :
1325                                 (&_resolve_static_ctr);
1326   Atomic::inc(addr);
1327 
1328   if (TraceCallFixup) {
1329     ResourceMark rm(current);
1330     tty->print("resolving %s%s (%s) call to",
1331                (is_optimized) ? "optimized " : "", (is_virtual) ? "virtual" : "static",
1332                Bytecodes::name(invoke_code));
1333     callee_method->print_short_name(tty);
1334     tty->print_cr(" at pc: " INTPTR_FORMAT " to code: " INTPTR_FORMAT,
1335                   p2i(caller_frame.pc()), p2i(callee_method->code()));
1336   }
1337 #endif
1338 
1339   if (invoke_code == Bytecodes::_invokestatic) {
1340     assert(callee_method->method_holder()->is_initialized() ||
1341            callee_method->method_holder()->is_init_thread(current),
1342            "invalid class initialization state for invoke_static");
1343     if (!VM_Version::supports_fast_class_init_checks() && callee_method->needs_clinit_barrier()) {
1344       // In order to keep class initialization check, do not patch call
1345       // site for static call when the class is not fully initialized.
1346       // Proper check is enforced by call site re-resolution on every invocation.
1347       //
1348       // When fast class initialization checks are supported (VM_Version::supports_fast_class_init_checks() == true),
1349       // explicit class initialization check is put in nmethod entry (VEP).
1350       assert(callee_method->method_holder()->is_linked(), "must be");
1351       return callee_method;
1352     }
1353   }
1354 
1355 
1356   // JSR 292 key invariant:
1357   // If the resolved method is a MethodHandle invoke target, the call
1358   // site must be a MethodHandle call site, because the lambda form might tail-call
1359   // leaving the stack in a state unknown to either caller or callee
1360 
1361   // Compute entry points. The computation of the entry points is independent of
1362   // patching the call.
1363 
1364   // Make sure the callee nmethod does not get deoptimized and removed before
1365   // we are done patching the code.
1366 
1367 
1368   CompiledICLocker ml(caller_nm);
1369   if (is_virtual && !is_optimized) {
1370     CompiledIC* inline_cache = CompiledIC_before(caller_nm, caller_frame.pc());
1371     inline_cache->update(&call_info, receiver->klass());
1372   } else {
1373     // Callsite is a direct call - set it to the destination method
1374     CompiledDirectCall* callsite = CompiledDirectCall::before(caller_frame.pc());
1375     callsite->set(callee_method);
1376   }
1377 
1378   return callee_method;
1379 }
1380 
1381 // Inline caches exist only in compiled code
1382 JRT_BLOCK_ENTRY(address, SharedRuntime::handle_wrong_method_ic_miss(JavaThread* current))
1383 #ifdef ASSERT
1384   RegisterMap reg_map(current,
1385                       RegisterMap::UpdateMap::skip,
1386                       RegisterMap::ProcessFrames::include,
1387                       RegisterMap::WalkContinuation::skip);
1388   frame stub_frame = current->last_frame();
1389   assert(stub_frame.is_runtime_frame(), "sanity check");
1390   frame caller_frame = stub_frame.sender(&reg_map);
1391   assert(!caller_frame.is_interpreted_frame() && !caller_frame.is_entry_frame() && !caller_frame.is_upcall_stub_frame(), "unexpected frame");
1392 #endif /* ASSERT */
1393 
1394   methodHandle callee_method;
1395   JRT_BLOCK
1396     callee_method = SharedRuntime::handle_ic_miss_helper(CHECK_NULL);
1397     // Return Method* through TLS
1398     current->set_vm_result_2(callee_method());
1399   JRT_BLOCK_END
1400   // return compiled code entry point after potential safepoints
1401   assert(callee_method->verified_code_entry() != nullptr, " Jump to zero!");
1402   return callee_method->verified_code_entry();
1403 JRT_END
1404 
1405 
1406 // Handle call site that has been made non-entrant
1407 JRT_BLOCK_ENTRY(address, SharedRuntime::handle_wrong_method(JavaThread* current))
1408   // 6243940 We might end up in here if the callee is deoptimized
1409   // as we race to call it.  We don't want to take a safepoint if
1410   // the caller was interpreted because the caller frame will look
1411   // interpreted to the stack walkers and arguments are now
1412   // "compiled" so it is much better to make this transition
1413   // invisible to the stack walking code. The i2c path will
1414   // place the callee method in the callee_target. It is stashed
1415   // there because if we try and find the callee by normal means a
1416   // safepoint is possible and have trouble gc'ing the compiled args.
1417   RegisterMap reg_map(current,
1418                       RegisterMap::UpdateMap::skip,
1419                       RegisterMap::ProcessFrames::include,
1420                       RegisterMap::WalkContinuation::skip);
1421   frame stub_frame = current->last_frame();
1422   assert(stub_frame.is_runtime_frame(), "sanity check");
1423   frame caller_frame = stub_frame.sender(&reg_map);
1424 
1425   if (caller_frame.is_interpreted_frame() ||
1426       caller_frame.is_entry_frame() ||
1427       caller_frame.is_upcall_stub_frame()) {
1428     Method* callee = current->callee_target();
1429     guarantee(callee != nullptr && callee->is_method(), "bad handshake");
1430     current->set_vm_result_2(callee);
1431     current->set_callee_target(nullptr);
1432     if (caller_frame.is_entry_frame() && VM_Version::supports_fast_class_init_checks()) {
1433       // Bypass class initialization checks in c2i when caller is in native.
1434       // JNI calls to static methods don't have class initialization checks.
1435       // Fast class initialization checks are present in c2i adapters and call into
1436       // SharedRuntime::handle_wrong_method() on the slow path.
1437       //
1438       // JVM upcalls may land here as well, but there's a proper check present in
1439       // LinkResolver::resolve_static_call (called from JavaCalls::call_static),
1440       // so bypassing it in c2i adapter is benign.
1441       return callee->get_c2i_no_clinit_check_entry();
1442     } else {
1443       return callee->get_c2i_entry();
1444     }
1445   }
1446 
1447   // Must be compiled to compiled path which is safe to stackwalk
1448   methodHandle callee_method;
1449   JRT_BLOCK
1450     // Force resolving of caller (if we called from compiled frame)
1451     callee_method = SharedRuntime::reresolve_call_site(CHECK_NULL);
1452     current->set_vm_result_2(callee_method());
1453   JRT_BLOCK_END
1454   // return compiled code entry point after potential safepoints
1455   assert(callee_method->verified_code_entry() != nullptr, " Jump to zero!");
1456   return callee_method->verified_code_entry();
1457 JRT_END
1458 
1459 // Handle abstract method call
1460 JRT_BLOCK_ENTRY(address, SharedRuntime::handle_wrong_method_abstract(JavaThread* current))
1461   // Verbose error message for AbstractMethodError.
1462   // Get the called method from the invoke bytecode.
1463   vframeStream vfst(current, true);
1464   assert(!vfst.at_end(), "Java frame must exist");
1465   methodHandle caller(current, vfst.method());
1466   Bytecode_invoke invoke(caller, vfst.bci());
1467   DEBUG_ONLY( invoke.verify(); )
1468 
1469   // Find the compiled caller frame.
1470   RegisterMap reg_map(current,
1471                       RegisterMap::UpdateMap::include,
1472                       RegisterMap::ProcessFrames::include,
1473                       RegisterMap::WalkContinuation::skip);
1474   frame stubFrame = current->last_frame();
1475   assert(stubFrame.is_runtime_frame(), "must be");
1476   frame callerFrame = stubFrame.sender(&reg_map);
1477   assert(callerFrame.is_compiled_frame(), "must be");
1478 
1479   // Install exception and return forward entry.
1480   address res = StubRoutines::throw_AbstractMethodError_entry();
1481   JRT_BLOCK
1482     methodHandle callee(current, invoke.static_target(current));
1483     if (!callee.is_null()) {
1484       oop recv = callerFrame.retrieve_receiver(&reg_map);
1485       Klass *recv_klass = (recv != nullptr) ? recv->klass() : nullptr;
1486       res = StubRoutines::forward_exception_entry();
1487       LinkResolver::throw_abstract_method_error(callee, recv_klass, CHECK_(res));
1488     }
1489   JRT_BLOCK_END
1490   return res;
1491 JRT_END
1492 
1493 
1494 // resolve a static call and patch code
1495 JRT_BLOCK_ENTRY(address, SharedRuntime::resolve_static_call_C(JavaThread* current ))
1496   methodHandle callee_method;
1497   bool enter_special = false;
1498   JRT_BLOCK
1499     callee_method = SharedRuntime::resolve_helper(false, false, CHECK_NULL);
1500     current->set_vm_result_2(callee_method());
1501 
1502     if (current->is_interp_only_mode()) {
1503       RegisterMap reg_map(current,
1504                           RegisterMap::UpdateMap::skip,
1505                           RegisterMap::ProcessFrames::include,
1506                           RegisterMap::WalkContinuation::skip);
1507       frame stub_frame = current->last_frame();
1508       assert(stub_frame.is_runtime_frame(), "must be a runtimeStub");
1509       frame caller = stub_frame.sender(&reg_map);
1510       enter_special = caller.cb() != nullptr && caller.cb()->is_compiled()
1511         && caller.cb()->as_compiled_method()->method()->is_continuation_enter_intrinsic();
1512     }
1513   JRT_BLOCK_END
1514 
1515   if (current->is_interp_only_mode() && enter_special) {
1516     // enterSpecial is compiled and calls this method to resolve the call to Continuation::enter
1517     // but in interp_only_mode we need to go to the interpreted entry
1518     // The c2i won't patch in this mode -- see fixup_callers_callsite
1519     //
1520     // This should probably be done in all cases, not just enterSpecial (see JDK-8218403),
1521     // but that's part of a larger fix, and the situation is worse for enterSpecial, as it has no
1522     // interpreted version.
1523     return callee_method->get_c2i_entry();
1524   }
1525 
1526   // return compiled code entry point after potential safepoints
1527   assert(callee_method->verified_code_entry() != nullptr, " Jump to zero!");
1528   return callee_method->verified_code_entry();
1529 JRT_END
1530 
1531 
1532 // resolve virtual call and update inline cache to monomorphic
1533 JRT_BLOCK_ENTRY(address, SharedRuntime::resolve_virtual_call_C(JavaThread* current))
1534   methodHandle callee_method;
1535   JRT_BLOCK
1536     callee_method = SharedRuntime::resolve_helper(true, false, CHECK_NULL);
1537     current->set_vm_result_2(callee_method());
1538   JRT_BLOCK_END
1539   // return compiled code entry point after potential safepoints
1540   assert(callee_method->verified_code_entry() != nullptr, " Jump to zero!");
1541   return callee_method->verified_code_entry();
1542 JRT_END
1543 
1544 
1545 // Resolve a virtual call that can be statically bound (e.g., always
1546 // monomorphic, so it has no inline cache).  Patch code to resolved target.
1547 JRT_BLOCK_ENTRY(address, SharedRuntime::resolve_opt_virtual_call_C(JavaThread* current))
1548   methodHandle callee_method;
1549   JRT_BLOCK
1550     callee_method = SharedRuntime::resolve_helper(true, true, CHECK_NULL);
1551     current->set_vm_result_2(callee_method());
1552   JRT_BLOCK_END
1553   // return compiled code entry point after potential safepoints
1554   assert(callee_method->verified_code_entry() != nullptr, " Jump to zero!");
1555   return callee_method->verified_code_entry();
1556 JRT_END
1557 
1558 methodHandle SharedRuntime::handle_ic_miss_helper(TRAPS) {
1559   JavaThread* current = THREAD;
1560   ResourceMark rm(current);
1561   CallInfo call_info;
1562   Bytecodes::Code bc;
1563 
1564   // receiver is null for static calls. An exception is thrown for null
1565   // receivers for non-static calls
1566   Handle receiver = find_callee_info(bc, call_info, CHECK_(methodHandle()));
1567 
1568   methodHandle callee_method(current, call_info.selected_method());
1569 
1570 #ifndef PRODUCT
1571   Atomic::inc(&_ic_miss_ctr);
1572 
1573   // Statistics & Tracing
1574   if (TraceCallFixup) {
1575     ResourceMark rm(current);
1576     tty->print("IC miss (%s) call to", Bytecodes::name(bc));
1577     callee_method->print_short_name(tty);
1578     tty->print_cr(" code: " INTPTR_FORMAT, p2i(callee_method->code()));
1579   }
1580 
1581   if (ICMissHistogram) {
1582     MutexLocker m(VMStatistic_lock);
1583     RegisterMap reg_map(current,
1584                         RegisterMap::UpdateMap::skip,
1585                         RegisterMap::ProcessFrames::include,
1586                         RegisterMap::WalkContinuation::skip);
1587     frame f = current->last_frame().real_sender(&reg_map);// skip runtime stub
1588     // produce statistics under the lock
1589     trace_ic_miss(f.pc());
1590   }
1591 #endif
1592 
1593   // install an event collector so that when a vtable stub is created the
1594   // profiler can be notified via a DYNAMIC_CODE_GENERATED event. The
1595   // event can't be posted when the stub is created as locks are held
1596   // - instead the event will be deferred until the event collector goes
1597   // out of scope.
1598   JvmtiDynamicCodeEventCollector event_collector;
1599 
1600   // Update inline cache to megamorphic. Skip update if we are called from interpreted.
1601   RegisterMap reg_map(current,
1602                       RegisterMap::UpdateMap::skip,
1603                       RegisterMap::ProcessFrames::include,
1604                       RegisterMap::WalkContinuation::skip);
1605   frame caller_frame = current->last_frame().sender(&reg_map);
1606   CodeBlob* cb = caller_frame.cb();
1607   CompiledMethod* caller_nm = cb->as_compiled_method();
1608 
1609   CompiledICLocker ml(caller_nm);
1610   CompiledIC* inline_cache = CompiledIC_before(caller_nm, caller_frame.pc());
1611   inline_cache->update(&call_info, receiver()->klass());
1612 
1613   return callee_method;
1614 }
1615 
1616 //
1617 // Resets a call-site in compiled code so it will get resolved again.
1618 // This routines handles both virtual call sites, optimized virtual call
1619 // sites, and static call sites. Typically used to change a call sites
1620 // destination from compiled to interpreted.
1621 //
1622 methodHandle SharedRuntime::reresolve_call_site(TRAPS) {
1623   JavaThread* current = THREAD;
1624   ResourceMark rm(current);
1625   RegisterMap reg_map(current,
1626                       RegisterMap::UpdateMap::skip,
1627                       RegisterMap::ProcessFrames::include,
1628                       RegisterMap::WalkContinuation::skip);
1629   frame stub_frame = current->last_frame();
1630   assert(stub_frame.is_runtime_frame(), "must be a runtimeStub");
1631   frame caller = stub_frame.sender(&reg_map);
1632 
1633   // Do nothing if the frame isn't a live compiled frame.
1634   // nmethod could be deoptimized by the time we get here
1635   // so no update to the caller is needed.
1636 
1637   if ((caller.is_compiled_frame() && !caller.is_deoptimized_frame()) ||
1638       (caller.is_native_frame() && ((CompiledMethod*)caller.cb())->method()->is_continuation_enter_intrinsic())) {
1639 
1640     address pc = caller.pc();
1641 
1642     CompiledMethod* caller_nm = CodeCache::find_compiled(pc);
1643 
1644     // Default call_addr is the location of the "basic" call.
1645     // Determine the address of the call we a reresolving. With
1646     // Inline Caches we will always find a recognizable call.
1647     // With Inline Caches disabled we may or may not find a
1648     // recognizable call. We will always find a call for static
1649     // calls and for optimized virtual calls. For vanilla virtual
1650     // calls it depends on the state of the UseInlineCaches switch.
1651     //
1652     // With Inline Caches disabled we can get here for a virtual call
1653     // for two reasons:
1654     //   1 - calling an abstract method. The vtable for abstract methods
1655     //       will run us thru handle_wrong_method and we will eventually
1656     //       end up in the interpreter to throw the ame.
1657     //   2 - a racing deoptimization. We could be doing a vanilla vtable
1658     //       call and between the time we fetch the entry address and
1659     //       we jump to it the target gets deoptimized. Similar to 1
1660     //       we will wind up in the interprter (thru a c2i with c2).
1661     //
1662     CompiledICLocker ml(caller_nm);
1663     address call_addr = caller_nm->call_instruction_address(pc);
1664 
1665     if (call_addr != nullptr) {
1666       // On x86 the logic for finding a call instruction is blindly checking for a call opcode 5
1667       // bytes back in the instruction stream so we must also check for reloc info.
1668       RelocIterator iter(caller_nm, call_addr, call_addr+1);
1669       bool ret = iter.next(); // Get item
1670       if (ret) {
1671         switch (iter.type()) {
1672           case relocInfo::static_call_type:
1673           case relocInfo::opt_virtual_call_type: {
1674             CompiledDirectCall* cdc = CompiledDirectCall::at(call_addr);
1675             cdc->set_to_clean();
1676             break;
1677           }
1678 
1679           case relocInfo::virtual_call_type: {
1680             // compiled, dispatched call (which used to call an interpreted method)
1681             CompiledIC* inline_cache = CompiledIC_at(caller_nm, call_addr);
1682             inline_cache->set_to_clean();
1683             break;
1684           }
1685           default:
1686             break;
1687         }
1688       }
1689     }
1690   }
1691 
1692   methodHandle callee_method = find_callee_method(CHECK_(methodHandle()));
1693 
1694 
1695 #ifndef PRODUCT
1696   Atomic::inc(&_wrong_method_ctr);
1697 
1698   if (TraceCallFixup) {
1699     ResourceMark rm(current);
1700     tty->print("handle_wrong_method reresolving call to");
1701     callee_method->print_short_name(tty);
1702     tty->print_cr(" code: " INTPTR_FORMAT, p2i(callee_method->code()));
1703   }
1704 #endif
1705 
1706   return callee_method;
1707 }
1708 
1709 address SharedRuntime::handle_unsafe_access(JavaThread* thread, address next_pc) {
1710   // The faulting unsafe accesses should be changed to throw the error
1711   // synchronously instead. Meanwhile the faulting instruction will be
1712   // skipped over (effectively turning it into a no-op) and an
1713   // asynchronous exception will be raised which the thread will
1714   // handle at a later point. If the instruction is a load it will
1715   // return garbage.
1716 
1717   // Request an async exception.
1718   thread->set_pending_unsafe_access_error();
1719 
1720   // Return address of next instruction to execute.
1721   return next_pc;
1722 }
1723 
1724 #ifdef ASSERT
1725 void SharedRuntime::check_member_name_argument_is_last_argument(const methodHandle& method,
1726                                                                 const BasicType* sig_bt,
1727                                                                 const VMRegPair* regs) {
1728   ResourceMark rm;
1729   const int total_args_passed = method->size_of_parameters();
1730   const VMRegPair*    regs_with_member_name = regs;
1731         VMRegPair* regs_without_member_name = NEW_RESOURCE_ARRAY(VMRegPair, total_args_passed - 1);
1732 
1733   const int member_arg_pos = total_args_passed - 1;
1734   assert(member_arg_pos >= 0 && member_arg_pos < total_args_passed, "oob");
1735   assert(sig_bt[member_arg_pos] == T_OBJECT, "dispatch argument must be an object");
1736 
1737   java_calling_convention(sig_bt, regs_without_member_name, total_args_passed - 1);
1738 
1739   for (int i = 0; i < member_arg_pos; i++) {
1740     VMReg a =    regs_with_member_name[i].first();
1741     VMReg b = regs_without_member_name[i].first();
1742     assert(a->value() == b->value(), "register allocation mismatch: a= %d, b= %d", a->value(), b->value());
1743   }
1744   assert(regs_with_member_name[member_arg_pos].first()->is_valid(), "bad member arg");
1745 }
1746 #endif
1747 
1748 // ---------------------------------------------------------------------------
1749 // We are calling the interpreter via a c2i. Normally this would mean that
1750 // we were called by a compiled method. However we could have lost a race
1751 // where we went int -> i2c -> c2i and so the caller could in fact be
1752 // interpreted. If the caller is compiled we attempt to patch the caller
1753 // so he no longer calls into the interpreter.
1754 JRT_LEAF(void, SharedRuntime::fixup_callers_callsite(Method* method, address caller_pc))
1755   AARCH64_PORT_ONLY(assert(pauth_ptr_is_raw(caller_pc), "should be raw"));
1756 
1757   // It's possible that deoptimization can occur at a call site which hasn't
1758   // been resolved yet, in which case this function will be called from
1759   // an nmethod that has been patched for deopt and we can ignore the
1760   // request for a fixup.
1761   // Also it is possible that we lost a race in that from_compiled_entry
1762   // is now back to the i2c in that case we don't need to patch and if
1763   // we did we'd leap into space because the callsite needs to use
1764   // "to interpreter" stub in order to load up the Method*. Don't
1765   // ask me how I know this...
1766 
1767   // Result from nmethod::is_unloading is not stable across safepoints.
1768   NoSafepointVerifier nsv;
1769 
1770   CompiledMethod* callee = method->code();
1771   if (callee == nullptr) {
1772     return;
1773   }
1774 
1775   // write lock needed because we might update the pc desc cache via PcDescCache::add_pc_desc
1776   MACOS_AARCH64_ONLY(ThreadWXEnable __wx(WXWrite, JavaThread::current()));
1777 
1778   CodeBlob* cb = CodeCache::find_blob(caller_pc);
1779   if (cb == nullptr || !cb->is_compiled() || !callee->is_in_use() || callee->is_unloading()) {
1780     return;
1781   }
1782 
1783   // The check above makes sure this is a nmethod.
1784   CompiledMethod* caller = cb->as_compiled_method();
1785 
1786   // Get the return PC for the passed caller PC.
1787   address return_pc = caller_pc + frame::pc_return_offset;
1788 
1789   if (!caller->is_in_use() || !NativeCall::is_call_before(return_pc)) {
1790     return;
1791   }
1792 
1793   // Expect to find a native call there (unless it was no-inline cache vtable dispatch)
1794   CompiledICLocker ic_locker(caller);
1795   ResourceMark rm;
1796 
1797   // If we got here through a static call or opt_virtual call, then we know where the
1798   // call address would be; let's peek at it
1799   address callsite_addr = (address)nativeCall_before(return_pc);
1800   RelocIterator iter(caller, callsite_addr, callsite_addr + 1);
1801   if (!iter.next()) {
1802     // No reloc entry found; not a static or optimized virtual call
1803     return;
1804   }
1805 
1806   relocInfo::relocType type = iter.reloc()->type();
1807   if (type != relocInfo::static_call_type &&
1808       type != relocInfo::opt_virtual_call_type) {
1809     return;
1810   }
1811 
1812   CompiledDirectCall* callsite = CompiledDirectCall::before(return_pc);
1813   callsite->set_to_clean();
1814 JRT_END
1815 
1816 
1817 // same as JVM_Arraycopy, but called directly from compiled code
1818 JRT_ENTRY(void, SharedRuntime::slow_arraycopy_C(oopDesc* src,  jint src_pos,
1819                                                 oopDesc* dest, jint dest_pos,
1820                                                 jint length,
1821                                                 JavaThread* current)) {
1822 #ifndef PRODUCT
1823   _slow_array_copy_ctr++;
1824 #endif
1825   // Check if we have null pointers
1826   if (src == nullptr || dest == nullptr) {
1827     THROW(vmSymbols::java_lang_NullPointerException());
1828   }
1829   // Do the copy.  The casts to arrayOop are necessary to the copy_array API,
1830   // even though the copy_array API also performs dynamic checks to ensure
1831   // that src and dest are truly arrays (and are conformable).
1832   // The copy_array mechanism is awkward and could be removed, but
1833   // the compilers don't call this function except as a last resort,
1834   // so it probably doesn't matter.
1835   src->klass()->copy_array((arrayOopDesc*)src, src_pos,
1836                                         (arrayOopDesc*)dest, dest_pos,
1837                                         length, current);
1838 }
1839 JRT_END
1840 
1841 // The caller of generate_class_cast_message() (or one of its callers)
1842 // must use a ResourceMark in order to correctly free the result.
1843 char* SharedRuntime::generate_class_cast_message(
1844     JavaThread* thread, Klass* caster_klass) {
1845 
1846   // Get target class name from the checkcast instruction
1847   vframeStream vfst(thread, true);
1848   assert(!vfst.at_end(), "Java frame must exist");
1849   Bytecode_checkcast cc(vfst.method(), vfst.method()->bcp_from(vfst.bci()));
1850   constantPoolHandle cpool(thread, vfst.method()->constants());
1851   Klass* target_klass = ConstantPool::klass_at_if_loaded(cpool, cc.index());
1852   Symbol* target_klass_name = nullptr;
1853   if (target_klass == nullptr) {
1854     // This klass should be resolved, but just in case, get the name in the klass slot.
1855     target_klass_name = cpool->klass_name_at(cc.index());
1856   }
1857   return generate_class_cast_message(caster_klass, target_klass, target_klass_name);
1858 }
1859 
1860 
1861 // The caller of generate_class_cast_message() (or one of its callers)
1862 // must use a ResourceMark in order to correctly free the result.
1863 char* SharedRuntime::generate_class_cast_message(
1864     Klass* caster_klass, Klass* target_klass, Symbol* target_klass_name) {
1865   const char* caster_name = caster_klass->external_name();
1866 
1867   assert(target_klass != nullptr || target_klass_name != nullptr, "one must be provided");
1868   const char* target_name = target_klass == nullptr ? target_klass_name->as_klass_external_name() :
1869                                                    target_klass->external_name();
1870 
1871   size_t msglen = strlen(caster_name) + strlen("class ") + strlen(" cannot be cast to class ") + strlen(target_name) + 1;
1872 
1873   const char* caster_klass_description = "";
1874   const char* target_klass_description = "";
1875   const char* klass_separator = "";
1876   if (target_klass != nullptr && caster_klass->module() == target_klass->module()) {
1877     caster_klass_description = caster_klass->joint_in_module_of_loader(target_klass);
1878   } else {
1879     caster_klass_description = caster_klass->class_in_module_of_loader();
1880     target_klass_description = (target_klass != nullptr) ? target_klass->class_in_module_of_loader() : "";
1881     klass_separator = (target_klass != nullptr) ? "; " : "";
1882   }
1883 
1884   // add 3 for parenthesis and preceding space
1885   msglen += strlen(caster_klass_description) + strlen(target_klass_description) + strlen(klass_separator) + 3;
1886 
1887   char* message = NEW_RESOURCE_ARRAY_RETURN_NULL(char, msglen);
1888   if (message == nullptr) {
1889     // Shouldn't happen, but don't cause even more problems if it does
1890     message = const_cast<char*>(caster_klass->external_name());
1891   } else {
1892     jio_snprintf(message,
1893                  msglen,
1894                  "class %s cannot be cast to class %s (%s%s%s)",
1895                  caster_name,
1896                  target_name,
1897                  caster_klass_description,
1898                  klass_separator,
1899                  target_klass_description
1900                  );
1901   }
1902   return message;
1903 }
1904 
1905 JRT_LEAF(void, SharedRuntime::reguard_yellow_pages())
1906   (void) JavaThread::current()->stack_overflow_state()->reguard_stack();
1907 JRT_END
1908 
1909 void SharedRuntime::monitor_enter_helper(oopDesc* obj, BasicLock* lock, JavaThread* current) {
1910   if (!SafepointSynchronize::is_synchronizing()) {
1911     // Only try quick_enter() if we're not trying to reach a safepoint
1912     // so that the calling thread reaches the safepoint more quickly.
1913     if (ObjectSynchronizer::quick_enter(obj, current, lock)) {
1914       return;
1915     }
1916   }
1917   // NO_ASYNC required because an async exception on the state transition destructor
1918   // would leave you with the lock held and it would never be released.
1919   // The normal monitorenter NullPointerException is thrown without acquiring a lock
1920   // and the model is that an exception implies the method failed.
1921   JRT_BLOCK_NO_ASYNC
1922   Handle h_obj(THREAD, obj);
1923   ThreadOnMonitorEnter tme(current);
1924   ObjectSynchronizer::enter(h_obj, lock, current);
1925   assert(!HAS_PENDING_EXCEPTION, "Should have no exception here");
1926   JRT_BLOCK_END
1927 }
1928 
1929 // Handles the uncommon case in locking, i.e., contention or an inflated lock.
1930 JRT_BLOCK_ENTRY(void, SharedRuntime::complete_monitor_locking_C(oopDesc* obj, BasicLock* lock, JavaThread* current))
1931   SharedRuntime::monitor_enter_helper(obj, lock, current);
1932 JRT_END
1933 
1934 JRT_LEAF(void, SharedRuntime::redo_monitorenter(JavaThread* current, ObjectMonitor* monitor))
1935   assert(current == JavaThread::current(), "invariant");
1936   assert(!monitor->is_owner(current), "invariant");
1937 
1938   monitor->redo_enter(current);
1939   assert(monitor->is_owner(current) || current->preempting(), "invariant");
1940 JRT_END
1941 
1942 void SharedRuntime::monitor_exit_helper(oopDesc* obj, BasicLock* lock, JavaThread* current) {
1943   assert(JavaThread::current() == current, "invariant");
1944   // Exit must be non-blocking, and therefore no exceptions can be thrown.
1945   ExceptionMark em(current);
1946   // The object could become unlocked through a JNI call, which we have no other checks for.
1947   // Give a fatal message if CheckJNICalls. Otherwise we ignore it.
1948   if (obj->is_unlocked()) {
1949     if (CheckJNICalls) {
1950       fatal("Object has been unlocked by JNI");
1951     }
1952     return;
1953   }
1954   ObjectSynchronizer::exit(obj, lock, current);
1955 }
1956 
1957 // Handles the uncommon cases of monitor unlocking in compiled code
1958 JRT_LEAF(void, SharedRuntime::complete_monitor_unlocking_C(oopDesc* obj, BasicLock* lock, JavaThread* current))
1959   assert(current == JavaThread::current(), "pre-condition");
1960   SharedRuntime::monitor_exit_helper(obj, lock, current);
1961 JRT_END
1962 
1963 #ifndef PRODUCT
1964 
1965 void SharedRuntime::print_statistics() {
1966   ttyLocker ttyl;
1967   if (xtty != nullptr)  xtty->head("statistics type='SharedRuntime'");
1968 
1969   SharedRuntime::print_ic_miss_histogram();
1970 
1971   // Dump the JRT_ENTRY counters
1972   if (_new_instance_ctr) tty->print_cr("%5u new instance requires GC", _new_instance_ctr);
1973   if (_new_array_ctr) tty->print_cr("%5u new array requires GC", _new_array_ctr);
1974   if (_multi2_ctr) tty->print_cr("%5u multianewarray 2 dim", _multi2_ctr);
1975   if (_multi3_ctr) tty->print_cr("%5u multianewarray 3 dim", _multi3_ctr);
1976   if (_multi4_ctr) tty->print_cr("%5u multianewarray 4 dim", _multi4_ctr);
1977   if (_multi5_ctr) tty->print_cr("%5u multianewarray 5 dim", _multi5_ctr);
1978 
1979   tty->print_cr("%5u inline cache miss in compiled", _ic_miss_ctr);
1980   tty->print_cr("%5u wrong method", _wrong_method_ctr);
1981   tty->print_cr("%5u unresolved static call site", _resolve_static_ctr);
1982   tty->print_cr("%5u unresolved virtual call site", _resolve_virtual_ctr);
1983   tty->print_cr("%5u unresolved opt virtual call site", _resolve_opt_virtual_ctr);
1984 
1985   if (_mon_enter_stub_ctr) tty->print_cr("%5u monitor enter stub", _mon_enter_stub_ctr);
1986   if (_mon_exit_stub_ctr) tty->print_cr("%5u monitor exit stub", _mon_exit_stub_ctr);
1987   if (_mon_enter_ctr) tty->print_cr("%5u monitor enter slow", _mon_enter_ctr);
1988   if (_mon_exit_ctr) tty->print_cr("%5u monitor exit slow", _mon_exit_ctr);
1989   if (_partial_subtype_ctr) tty->print_cr("%5u slow partial subtype", _partial_subtype_ctr);
1990   if (_jbyte_array_copy_ctr) tty->print_cr("%5u byte array copies", _jbyte_array_copy_ctr);
1991   if (_jshort_array_copy_ctr) tty->print_cr("%5u short array copies", _jshort_array_copy_ctr);
1992   if (_jint_array_copy_ctr) tty->print_cr("%5u int array copies", _jint_array_copy_ctr);
1993   if (_jlong_array_copy_ctr) tty->print_cr("%5u long array copies", _jlong_array_copy_ctr);
1994   if (_oop_array_copy_ctr) tty->print_cr("%5u oop array copies", _oop_array_copy_ctr);
1995   if (_checkcast_array_copy_ctr) tty->print_cr("%5u checkcast array copies", _checkcast_array_copy_ctr);
1996   if (_unsafe_array_copy_ctr) tty->print_cr("%5u unsafe array copies", _unsafe_array_copy_ctr);
1997   if (_generic_array_copy_ctr) tty->print_cr("%5u generic array copies", _generic_array_copy_ctr);
1998   if (_slow_array_copy_ctr) tty->print_cr("%5u slow array copies", _slow_array_copy_ctr);
1999   if (_find_handler_ctr) tty->print_cr("%5u find exception handler", _find_handler_ctr);
2000   if (_rethrow_ctr) tty->print_cr("%5u rethrow handler", _rethrow_ctr);
2001 
2002   AdapterHandlerLibrary::print_statistics();
2003 
2004   if (xtty != nullptr)  xtty->tail("statistics");
2005 }
2006 
2007 inline double percent(int64_t x, int64_t y) {
2008   return 100.0 * (double)x / (double)MAX2(y, (int64_t)1);
2009 }
2010 
2011 class MethodArityHistogram {
2012  public:
2013   enum { MAX_ARITY = 256 };
2014  private:
2015   static uint64_t _arity_histogram[MAX_ARITY]; // histogram of #args
2016   static uint64_t _size_histogram[MAX_ARITY];  // histogram of arg size in words
2017   static uint64_t _total_compiled_calls;
2018   static uint64_t _max_compiled_calls_per_method;
2019   static int _max_arity;                       // max. arity seen
2020   static int _max_size;                        // max. arg size seen
2021 
2022   static void add_method_to_histogram(nmethod* nm) {
2023     Method* method = (nm == nullptr) ? nullptr : nm->method();
2024     if (method != nullptr) {
2025       ArgumentCount args(method->signature());
2026       int arity   = args.size() + (method->is_static() ? 0 : 1);
2027       int argsize = method->size_of_parameters();
2028       arity   = MIN2(arity, MAX_ARITY-1);
2029       argsize = MIN2(argsize, MAX_ARITY-1);
2030       uint64_t count = (uint64_t)method->compiled_invocation_count();
2031       _max_compiled_calls_per_method = count > _max_compiled_calls_per_method ? count : _max_compiled_calls_per_method;
2032       _total_compiled_calls    += count;
2033       _arity_histogram[arity]  += count;
2034       _size_histogram[argsize] += count;
2035       _max_arity = MAX2(_max_arity, arity);
2036       _max_size  = MAX2(_max_size, argsize);
2037     }
2038   }
2039 
2040   void print_histogram_helper(int n, uint64_t* histo, const char* name) {
2041     const int N = MIN2(9, n);
2042     double sum = 0;
2043     double weighted_sum = 0;
2044     for (int i = 0; i <= n; i++) { sum += (double)histo[i]; weighted_sum += (double)(i*histo[i]); }
2045     if (sum >= 1) { // prevent divide by zero or divide overflow
2046       double rest = sum;
2047       double percent = sum / 100;
2048       for (int i = 0; i <= N; i++) {
2049         rest -= (double)histo[i];
2050         tty->print_cr("%4d: " UINT64_FORMAT_W(12) " (%5.1f%%)", i, histo[i], (double)histo[i] / percent);
2051       }
2052       tty->print_cr("rest: " INT64_FORMAT_W(12) " (%5.1f%%)", (int64_t)rest, rest / percent);
2053       tty->print_cr("(avg. %s = %3.1f, max = %d)", name, weighted_sum / sum, n);
2054       tty->print_cr("(total # of compiled calls = " INT64_FORMAT_W(14) ")", _total_compiled_calls);
2055       tty->print_cr("(max # of compiled calls   = " INT64_FORMAT_W(14) ")", _max_compiled_calls_per_method);
2056     } else {
2057       tty->print_cr("Histogram generation failed for %s. n = %d, sum = %7.5f", name, n, sum);
2058     }
2059   }
2060 
2061   void print_histogram() {
2062     tty->print_cr("\nHistogram of call arity (incl. rcvr, calls to compiled methods only):");
2063     print_histogram_helper(_max_arity, _arity_histogram, "arity");
2064     tty->print_cr("\nHistogram of parameter block size (in words, incl. rcvr):");
2065     print_histogram_helper(_max_size, _size_histogram, "size");
2066     tty->cr();
2067   }
2068 
2069  public:
2070   MethodArityHistogram() {
2071     // Take the Compile_lock to protect against changes in the CodeBlob structures
2072     MutexLocker mu1(Compile_lock, Mutex::_safepoint_check_flag);
2073     // Take the CodeCache_lock to protect against changes in the CodeHeap structure
2074     MutexLocker mu2(CodeCache_lock, Mutex::_no_safepoint_check_flag);
2075     _max_arity = _max_size = 0;
2076     _total_compiled_calls = 0;
2077     _max_compiled_calls_per_method = 0;
2078     for (int i = 0; i < MAX_ARITY; i++) _arity_histogram[i] = _size_histogram[i] = 0;
2079     CodeCache::nmethods_do(add_method_to_histogram);
2080     print_histogram();
2081   }
2082 };
2083 
2084 uint64_t MethodArityHistogram::_arity_histogram[MethodArityHistogram::MAX_ARITY];
2085 uint64_t MethodArityHistogram::_size_histogram[MethodArityHistogram::MAX_ARITY];
2086 uint64_t MethodArityHistogram::_total_compiled_calls;
2087 uint64_t MethodArityHistogram::_max_compiled_calls_per_method;
2088 int MethodArityHistogram::_max_arity;
2089 int MethodArityHistogram::_max_size;
2090 
2091 void SharedRuntime::print_call_statistics(uint64_t comp_total) {
2092   tty->print_cr("Calls from compiled code:");
2093   int64_t total  = _nof_normal_calls + _nof_interface_calls + _nof_static_calls;
2094   int64_t mono_c = _nof_normal_calls - _nof_megamorphic_calls;
2095   int64_t mono_i = _nof_interface_calls;
2096   tty->print_cr("\t" INT64_FORMAT_W(12) " (100%%)  total non-inlined   ", total);
2097   tty->print_cr("\t" INT64_FORMAT_W(12) " (%4.1f%%) |- virtual calls       ", _nof_normal_calls, percent(_nof_normal_calls, total));
2098   tty->print_cr("\t" INT64_FORMAT_W(12) " (%4.0f%%) |  |- inlined          ", _nof_inlined_calls, percent(_nof_inlined_calls, _nof_normal_calls));
2099   tty->print_cr("\t" INT64_FORMAT_W(12) " (%4.0f%%) |  |- monomorphic      ", mono_c, percent(mono_c, _nof_normal_calls));
2100   tty->print_cr("\t" INT64_FORMAT_W(12) " (%4.0f%%) |  |- megamorphic      ", _nof_megamorphic_calls, percent(_nof_megamorphic_calls, _nof_normal_calls));
2101   tty->print_cr("\t" INT64_FORMAT_W(12) " (%4.1f%%) |- interface calls     ", _nof_interface_calls, percent(_nof_interface_calls, total));
2102   tty->print_cr("\t" INT64_FORMAT_W(12) " (%4.0f%%) |  |- inlined          ", _nof_inlined_interface_calls, percent(_nof_inlined_interface_calls, _nof_interface_calls));
2103   tty->print_cr("\t" INT64_FORMAT_W(12) " (%4.0f%%) |  |- monomorphic      ", mono_i, percent(mono_i, _nof_interface_calls));
2104   tty->print_cr("\t" INT64_FORMAT_W(12) " (%4.1f%%) |- static/special calls", _nof_static_calls, percent(_nof_static_calls, total));
2105   tty->print_cr("\t" INT64_FORMAT_W(12) " (%4.0f%%) |  |- inlined          ", _nof_inlined_static_calls, percent(_nof_inlined_static_calls, _nof_static_calls));
2106   tty->cr();
2107   tty->print_cr("Note 1: counter updates are not MT-safe.");
2108   tty->print_cr("Note 2: %% in major categories are relative to total non-inlined calls;");
2109   tty->print_cr("        %% in nested categories are relative to their category");
2110   tty->print_cr("        (and thus add up to more than 100%% with inlining)");
2111   tty->cr();
2112 
2113   MethodArityHistogram h;
2114 }
2115 #endif
2116 
2117 #ifndef PRODUCT
2118 static int _lookups; // number of calls to lookup
2119 static int _equals;  // number of buckets checked with matching hash
2120 static int _hits;    // number of successful lookups
2121 static int _compact; // number of equals calls with compact signature
2122 #endif
2123 
2124 // A simple wrapper class around the calling convention information
2125 // that allows sharing of adapters for the same calling convention.
2126 class AdapterFingerPrint : public CHeapObj<mtCode> {
2127  private:
2128   enum {
2129     _basic_type_bits = 4,
2130     _basic_type_mask = right_n_bits(_basic_type_bits),
2131     _basic_types_per_int = BitsPerInt / _basic_type_bits,
2132     _compact_int_count = 3
2133   };
2134   // TO DO:  Consider integrating this with a more global scheme for compressing signatures.
2135   // For now, 4 bits per components (plus T_VOID gaps after double/long) is not excessive.
2136 
2137   union {
2138     int  _compact[_compact_int_count];
2139     int* _fingerprint;
2140   } _value;
2141   int _length; // A negative length indicates the fingerprint is in the compact form,
2142                // Otherwise _value._fingerprint is the array.
2143 
2144   // Remap BasicTypes that are handled equivalently by the adapters.
2145   // These are correct for the current system but someday it might be
2146   // necessary to make this mapping platform dependent.
2147   static int adapter_encoding(BasicType in) {
2148     switch (in) {
2149       case T_BOOLEAN:
2150       case T_BYTE:
2151       case T_SHORT:
2152       case T_CHAR:
2153         // There are all promoted to T_INT in the calling convention
2154         return T_INT;
2155 
2156       case T_OBJECT:
2157       case T_ARRAY:
2158         // In other words, we assume that any register good enough for
2159         // an int or long is good enough for a managed pointer.
2160 #ifdef _LP64
2161         return T_LONG;
2162 #else
2163         return T_INT;
2164 #endif
2165 
2166       case T_INT:
2167       case T_LONG:
2168       case T_FLOAT:
2169       case T_DOUBLE:
2170       case T_VOID:
2171         return in;
2172 
2173       default:
2174         ShouldNotReachHere();
2175         return T_CONFLICT;
2176     }
2177   }
2178 
2179  public:
2180   AdapterFingerPrint(int total_args_passed, BasicType* sig_bt) {
2181     // The fingerprint is based on the BasicType signature encoded
2182     // into an array of ints with eight entries per int.
2183     int* ptr;
2184     int len = (total_args_passed + (_basic_types_per_int-1)) / _basic_types_per_int;
2185     if (len <= _compact_int_count) {
2186       assert(_compact_int_count == 3, "else change next line");
2187       _value._compact[0] = _value._compact[1] = _value._compact[2] = 0;
2188       // Storing the signature encoded as signed chars hits about 98%
2189       // of the time.
2190       _length = -len;
2191       ptr = _value._compact;
2192     } else {
2193       _length = len;
2194       _value._fingerprint = NEW_C_HEAP_ARRAY(int, _length, mtCode);
2195       ptr = _value._fingerprint;
2196     }
2197 
2198     // Now pack the BasicTypes with 8 per int
2199     int sig_index = 0;
2200     for (int index = 0; index < len; index++) {
2201       int value = 0;
2202       for (int byte = 0; sig_index < total_args_passed && byte < _basic_types_per_int; byte++) {
2203         int bt = adapter_encoding(sig_bt[sig_index++]);
2204         assert((bt & _basic_type_mask) == bt, "must fit in 4 bits");
2205         value = (value << _basic_type_bits) | bt;
2206       }
2207       ptr[index] = value;
2208     }
2209   }
2210 
2211   ~AdapterFingerPrint() {
2212     if (_length > 0) {
2213       FREE_C_HEAP_ARRAY(int, _value._fingerprint);
2214     }
2215   }
2216 
2217   int value(int index) {
2218     if (_length < 0) {
2219       return _value._compact[index];
2220     }
2221     return _value._fingerprint[index];
2222   }
2223   int length() {
2224     if (_length < 0) return -_length;
2225     return _length;
2226   }
2227 
2228   bool is_compact() {
2229     return _length <= 0;
2230   }
2231 
2232   unsigned int compute_hash() {
2233     int hash = 0;
2234     for (int i = 0; i < length(); i++) {
2235       int v = value(i);
2236       hash = (hash << 8) ^ v ^ (hash >> 5);
2237     }
2238     return (unsigned int)hash;
2239   }
2240 
2241   const char* as_string() {
2242     stringStream st;
2243     st.print("0x");
2244     for (int i = 0; i < length(); i++) {
2245       st.print("%x", value(i));
2246     }
2247     return st.as_string();
2248   }
2249 
2250 #ifndef PRODUCT
2251   // Reconstitutes the basic type arguments from the fingerprint,
2252   // producing strings like LIJDF
2253   const char* as_basic_args_string() {
2254     stringStream st;
2255     bool long_prev = false;
2256     for (int i = 0; i < length(); i++) {
2257       unsigned val = (unsigned)value(i);
2258       // args are packed so that first/lower arguments are in the highest
2259       // bits of each int value, so iterate from highest to the lowest
2260       for (int j = 32 - _basic_type_bits; j >= 0; j -= _basic_type_bits) {
2261         unsigned v = (val >> j) & _basic_type_mask;
2262         if (v == 0) {
2263           assert(i == length() - 1, "Only expect zeroes in the last word");
2264           continue;
2265         }
2266         if (long_prev) {
2267           long_prev = false;
2268           if (v == T_VOID) {
2269             st.print("J");
2270           } else {
2271             st.print("L");
2272           }
2273         }
2274         switch (v) {
2275           case T_INT:    st.print("I");    break;
2276           case T_LONG:   long_prev = true; break;
2277           case T_FLOAT:  st.print("F");    break;
2278           case T_DOUBLE: st.print("D");    break;
2279           case T_VOID:   break;
2280           default: ShouldNotReachHere();
2281         }
2282       }
2283     }
2284     if (long_prev) {
2285       st.print("L");
2286     }
2287     return st.as_string();
2288   }
2289 #endif // !product
2290 
2291   bool equals(AdapterFingerPrint* other) {
2292     if (other->_length != _length) {
2293       return false;
2294     }
2295     if (_length < 0) {
2296       assert(_compact_int_count == 3, "else change next line");
2297       return _value._compact[0] == other->_value._compact[0] &&
2298              _value._compact[1] == other->_value._compact[1] &&
2299              _value._compact[2] == other->_value._compact[2];
2300     } else {
2301       for (int i = 0; i < _length; i++) {
2302         if (_value._fingerprint[i] != other->_value._fingerprint[i]) {
2303           return false;
2304         }
2305       }
2306     }
2307     return true;
2308   }
2309 
2310   static bool equals(AdapterFingerPrint* const& fp1, AdapterFingerPrint* const& fp2) {
2311     NOT_PRODUCT(_equals++);
2312     return fp1->equals(fp2);
2313   }
2314 
2315   static unsigned int compute_hash(AdapterFingerPrint* const& fp) {
2316     return fp->compute_hash();
2317   }
2318 };
2319 
2320 // A hashtable mapping from AdapterFingerPrints to AdapterHandlerEntries
2321 using AdapterHandlerTable = ResourceHashtable<AdapterFingerPrint*, AdapterHandlerEntry*, 293,
2322                   AnyObj::C_HEAP, mtCode,
2323                   AdapterFingerPrint::compute_hash,
2324                   AdapterFingerPrint::equals>;
2325 static AdapterHandlerTable* _adapter_handler_table;
2326 
2327 // Find a entry with the same fingerprint if it exists
2328 static AdapterHandlerEntry* lookup(int total_args_passed, BasicType* sig_bt) {
2329   NOT_PRODUCT(_lookups++);
2330   assert_lock_strong(AdapterHandlerLibrary_lock);
2331   AdapterFingerPrint fp(total_args_passed, sig_bt);
2332   AdapterHandlerEntry** entry = _adapter_handler_table->get(&fp);
2333   if (entry != nullptr) {
2334 #ifndef PRODUCT
2335     if (fp.is_compact()) _compact++;
2336     _hits++;
2337 #endif
2338     return *entry;
2339   }
2340   return nullptr;
2341 }
2342 
2343 #ifndef PRODUCT
2344 static void print_table_statistics() {
2345   auto size = [&] (AdapterFingerPrint* key, AdapterHandlerEntry* a) {
2346     return sizeof(*key) + sizeof(*a);
2347   };
2348   TableStatistics ts = _adapter_handler_table->statistics_calculate(size);
2349   ts.print(tty, "AdapterHandlerTable");
2350   tty->print_cr("AdapterHandlerTable (table_size=%d, entries=%d)",
2351                 _adapter_handler_table->table_size(), _adapter_handler_table->number_of_entries());
2352   tty->print_cr("AdapterHandlerTable: lookups %d equals %d hits %d compact %d",
2353                 _lookups, _equals, _hits, _compact);
2354 }
2355 #endif
2356 
2357 // ---------------------------------------------------------------------------
2358 // Implementation of AdapterHandlerLibrary
2359 AdapterHandlerEntry* AdapterHandlerLibrary::_abstract_method_handler = nullptr;
2360 AdapterHandlerEntry* AdapterHandlerLibrary::_no_arg_handler = nullptr;
2361 AdapterHandlerEntry* AdapterHandlerLibrary::_int_arg_handler = nullptr;
2362 AdapterHandlerEntry* AdapterHandlerLibrary::_obj_arg_handler = nullptr;
2363 AdapterHandlerEntry* AdapterHandlerLibrary::_obj_int_arg_handler = nullptr;
2364 AdapterHandlerEntry* AdapterHandlerLibrary::_obj_obj_arg_handler = nullptr;
2365 const int AdapterHandlerLibrary_size = 16*K;
2366 BufferBlob* AdapterHandlerLibrary::_buffer = nullptr;
2367 
2368 BufferBlob* AdapterHandlerLibrary::buffer_blob() {
2369   return _buffer;
2370 }
2371 
2372 static void post_adapter_creation(const AdapterBlob* new_adapter,
2373                                   const AdapterHandlerEntry* entry) {
2374   if (Forte::is_enabled() || JvmtiExport::should_post_dynamic_code_generated()) {
2375     char blob_id[256];
2376     jio_snprintf(blob_id,
2377                  sizeof(blob_id),
2378                  "%s(%s)",
2379                  new_adapter->name(),
2380                  entry->fingerprint()->as_string());
2381     if (Forte::is_enabled()) {
2382       Forte::register_stub(blob_id, new_adapter->content_begin(), new_adapter->content_end());
2383     }
2384 
2385     if (JvmtiExport::should_post_dynamic_code_generated()) {
2386       JvmtiExport::post_dynamic_code_generated(blob_id, new_adapter->content_begin(), new_adapter->content_end());
2387     }
2388   }
2389 }
2390 
2391 void AdapterHandlerLibrary::initialize() {
2392   ResourceMark rm;
2393   AdapterBlob* no_arg_blob = nullptr;
2394   AdapterBlob* int_arg_blob = nullptr;
2395   AdapterBlob* obj_arg_blob = nullptr;
2396   AdapterBlob* obj_int_arg_blob = nullptr;
2397   AdapterBlob* obj_obj_arg_blob = nullptr;
2398   {
2399     _adapter_handler_table = new (mtCode) AdapterHandlerTable();
2400     MutexLocker mu(AdapterHandlerLibrary_lock);
2401 
2402     // Create a special handler for abstract methods.  Abstract methods
2403     // are never compiled so an i2c entry is somewhat meaningless, but
2404     // throw AbstractMethodError just in case.
2405     // Pass wrong_method_abstract for the c2i transitions to return
2406     // AbstractMethodError for invalid invocations.
2407     address wrong_method_abstract = SharedRuntime::get_handle_wrong_method_abstract_stub();
2408     _abstract_method_handler = AdapterHandlerLibrary::new_entry(new AdapterFingerPrint(0, nullptr),
2409                                                                 StubRoutines::throw_AbstractMethodError_entry(),
2410                                                                 wrong_method_abstract, wrong_method_abstract);
2411 
2412     _buffer = BufferBlob::create("adapters", AdapterHandlerLibrary_size);
2413     _no_arg_handler = create_adapter(no_arg_blob, 0, nullptr, true);
2414 
2415     BasicType obj_args[] = { T_OBJECT };
2416     _obj_arg_handler = create_adapter(obj_arg_blob, 1, obj_args, true);
2417 
2418     BasicType int_args[] = { T_INT };
2419     _int_arg_handler = create_adapter(int_arg_blob, 1, int_args, true);
2420 
2421     BasicType obj_int_args[] = { T_OBJECT, T_INT };
2422     _obj_int_arg_handler = create_adapter(obj_int_arg_blob, 2, obj_int_args, true);
2423 
2424     BasicType obj_obj_args[] = { T_OBJECT, T_OBJECT };
2425     _obj_obj_arg_handler = create_adapter(obj_obj_arg_blob, 2, obj_obj_args, true);
2426 
2427     assert(no_arg_blob != nullptr &&
2428           obj_arg_blob != nullptr &&
2429           int_arg_blob != nullptr &&
2430           obj_int_arg_blob != nullptr &&
2431           obj_obj_arg_blob != nullptr, "Initial adapters must be properly created");
2432   }
2433 
2434   // Outside of the lock
2435   post_adapter_creation(no_arg_blob, _no_arg_handler);
2436   post_adapter_creation(obj_arg_blob, _obj_arg_handler);
2437   post_adapter_creation(int_arg_blob, _int_arg_handler);
2438   post_adapter_creation(obj_int_arg_blob, _obj_int_arg_handler);
2439   post_adapter_creation(obj_obj_arg_blob, _obj_obj_arg_handler);
2440 }
2441 
2442 AdapterHandlerEntry* AdapterHandlerLibrary::new_entry(AdapterFingerPrint* fingerprint,
2443                                                       address i2c_entry,
2444                                                       address c2i_entry,
2445                                                       address c2i_unverified_entry,
2446                                                       address c2i_no_clinit_check_entry) {
2447   // Insert an entry into the table
2448   return new AdapterHandlerEntry(fingerprint, i2c_entry, c2i_entry, c2i_unverified_entry,
2449                                  c2i_no_clinit_check_entry);
2450 }
2451 
2452 AdapterHandlerEntry* AdapterHandlerLibrary::get_simple_adapter(const methodHandle& method) {
2453   if (method->is_abstract()) {
2454     return _abstract_method_handler;
2455   }
2456   int total_args_passed = method->size_of_parameters(); // All args on stack
2457   if (total_args_passed == 0) {
2458     return _no_arg_handler;
2459   } else if (total_args_passed == 1) {
2460     if (!method->is_static()) {
2461       return _obj_arg_handler;
2462     }
2463     switch (method->signature()->char_at(1)) {
2464       case JVM_SIGNATURE_CLASS:
2465       case JVM_SIGNATURE_ARRAY:
2466         return _obj_arg_handler;
2467       case JVM_SIGNATURE_INT:
2468       case JVM_SIGNATURE_BOOLEAN:
2469       case JVM_SIGNATURE_CHAR:
2470       case JVM_SIGNATURE_BYTE:
2471       case JVM_SIGNATURE_SHORT:
2472         return _int_arg_handler;
2473     }
2474   } else if (total_args_passed == 2 &&
2475              !method->is_static()) {
2476     switch (method->signature()->char_at(1)) {
2477       case JVM_SIGNATURE_CLASS:
2478       case JVM_SIGNATURE_ARRAY:
2479         return _obj_obj_arg_handler;
2480       case JVM_SIGNATURE_INT:
2481       case JVM_SIGNATURE_BOOLEAN:
2482       case JVM_SIGNATURE_CHAR:
2483       case JVM_SIGNATURE_BYTE:
2484       case JVM_SIGNATURE_SHORT:
2485         return _obj_int_arg_handler;
2486     }
2487   }
2488   return nullptr;
2489 }
2490 
2491 class AdapterSignatureIterator : public SignatureIterator {
2492  private:
2493   BasicType stack_sig_bt[16];
2494   BasicType* sig_bt;
2495   int index;
2496 
2497  public:
2498   AdapterSignatureIterator(Symbol* signature,
2499                            fingerprint_t fingerprint,
2500                            bool is_static,
2501                            int total_args_passed) :
2502     SignatureIterator(signature, fingerprint),
2503     index(0)
2504   {
2505     sig_bt = (total_args_passed <= 16) ? stack_sig_bt : NEW_RESOURCE_ARRAY(BasicType, total_args_passed);
2506     if (!is_static) { // Pass in receiver first
2507       sig_bt[index++] = T_OBJECT;
2508     }
2509     do_parameters_on(this);
2510   }
2511 
2512   BasicType* basic_types() {
2513     return sig_bt;
2514   }
2515 
2516 #ifdef ASSERT
2517   int slots() {
2518     return index;
2519   }
2520 #endif
2521 
2522  private:
2523 
2524   friend class SignatureIterator;  // so do_parameters_on can call do_type
2525   void do_type(BasicType type) {
2526     sig_bt[index++] = type;
2527     if (type == T_LONG || type == T_DOUBLE) {
2528       sig_bt[index++] = T_VOID; // Longs & doubles take 2 Java slots
2529     }
2530   }
2531 };
2532 
2533 AdapterHandlerEntry* AdapterHandlerLibrary::get_adapter(const methodHandle& method) {
2534   // Use customized signature handler.  Need to lock around updates to
2535   // the _adapter_handler_table (it is not safe for concurrent readers
2536   // and a single writer: this could be fixed if it becomes a
2537   // problem).
2538 
2539   // Fast-path for trivial adapters
2540   AdapterHandlerEntry* entry = get_simple_adapter(method);
2541   if (entry != nullptr) {
2542     return entry;
2543   }
2544 
2545   ResourceMark rm;
2546   AdapterBlob* new_adapter = nullptr;
2547 
2548   // Fill in the signature array, for the calling-convention call.
2549   int total_args_passed = method->size_of_parameters(); // All args on stack
2550 
2551   AdapterSignatureIterator si(method->signature(), method->constMethod()->fingerprint(),
2552                               method->is_static(), total_args_passed);
2553   assert(si.slots() == total_args_passed, "");
2554   BasicType* sig_bt = si.basic_types();
2555   {
2556     MutexLocker mu(AdapterHandlerLibrary_lock);
2557 
2558     // Lookup method signature's fingerprint
2559     entry = lookup(total_args_passed, sig_bt);
2560 
2561     if (entry != nullptr) {
2562 #ifdef ASSERT
2563       if (VerifyAdapterSharing) {
2564         AdapterBlob* comparison_blob = nullptr;
2565         AdapterHandlerEntry* comparison_entry = create_adapter(comparison_blob, total_args_passed, sig_bt, false);
2566         assert(comparison_blob == nullptr, "no blob should be created when creating an adapter for comparison");
2567         assert(comparison_entry->compare_code(entry), "code must match");
2568         // Release the one just created and return the original
2569         delete comparison_entry;
2570       }
2571 #endif
2572       return entry;
2573     }
2574 
2575     entry = create_adapter(new_adapter, total_args_passed, sig_bt, /* allocate_code_blob */ true);
2576   }
2577 
2578   // Outside of the lock
2579   if (new_adapter != nullptr) {
2580     post_adapter_creation(new_adapter, entry);
2581   }
2582   return entry;
2583 }
2584 
2585 AdapterHandlerEntry* AdapterHandlerLibrary::create_adapter(AdapterBlob*& new_adapter,
2586                                                            int total_args_passed,
2587                                                            BasicType* sig_bt,
2588                                                            bool allocate_code_blob) {
2589 
2590   // StubRoutines::_final_stubs_code is initialized after this function can be called. As a result,
2591   // VerifyAdapterCalls and VerifyAdapterSharing can fail if we re-use code that generated prior
2592   // to all StubRoutines::_final_stubs_code being set. Checks refer to runtime range checks generated
2593   // in an I2C stub that ensure that an I2C stub is called from an interpreter frame or stubs.
2594   bool contains_all_checks = StubRoutines::final_stubs_code() != nullptr;
2595 
2596   VMRegPair stack_regs[16];
2597   VMRegPair* regs = (total_args_passed <= 16) ? stack_regs : NEW_RESOURCE_ARRAY(VMRegPair, total_args_passed);
2598 
2599   // Get a description of the compiled java calling convention and the largest used (VMReg) stack slot usage
2600   int comp_args_on_stack = SharedRuntime::java_calling_convention(sig_bt, regs, total_args_passed);
2601   BufferBlob* buf = buffer_blob(); // the temporary code buffer in CodeCache
2602   CodeBuffer buffer(buf);
2603   short buffer_locs[20];
2604   buffer.insts()->initialize_shared_locs((relocInfo*)buffer_locs,
2605                                           sizeof(buffer_locs)/sizeof(relocInfo));
2606 
2607   // Make a C heap allocated version of the fingerprint to store in the adapter
2608   AdapterFingerPrint* fingerprint = new AdapterFingerPrint(total_args_passed, sig_bt);
2609   MacroAssembler _masm(&buffer);
2610   AdapterHandlerEntry* entry = SharedRuntime::generate_i2c2i_adapters(&_masm,
2611                                                 total_args_passed,
2612                                                 comp_args_on_stack,
2613                                                 sig_bt,
2614                                                 regs,
2615                                                 fingerprint);
2616 
2617 #ifdef ASSERT
2618   if (VerifyAdapterSharing) {
2619     entry->save_code(buf->code_begin(), buffer.insts_size());
2620     if (!allocate_code_blob) {
2621       return entry;
2622     }
2623   }
2624 #endif
2625 
2626   new_adapter = AdapterBlob::create(&buffer);
2627   NOT_PRODUCT(int insts_size = buffer.insts_size());
2628   if (new_adapter == nullptr) {
2629     // CodeCache is full, disable compilation
2630     // Ought to log this but compile log is only per compile thread
2631     // and we're some non descript Java thread.
2632     return nullptr;
2633   }
2634   entry->relocate(new_adapter->content_begin());
2635 #ifndef PRODUCT
2636   // debugging support
2637   if (PrintAdapterHandlers || PrintStubCode) {
2638     ttyLocker ttyl;
2639     entry->print_adapter_on(tty);
2640     tty->print_cr("i2c argument handler #%d for: %s %s (%d bytes generated)",
2641                   _adapter_handler_table->number_of_entries(), fingerprint->as_basic_args_string(),
2642                   fingerprint->as_string(), insts_size);
2643     tty->print_cr("c2i argument handler starts at " INTPTR_FORMAT, p2i(entry->get_c2i_entry()));
2644     if (Verbose || PrintStubCode) {
2645       address first_pc = entry->base_address();
2646       if (first_pc != nullptr) {
2647         Disassembler::decode(first_pc, first_pc + insts_size, tty
2648                              NOT_PRODUCT(COMMA &new_adapter->asm_remarks()));
2649         tty->cr();
2650       }
2651     }
2652   }
2653 #endif
2654 
2655   // Add the entry only if the entry contains all required checks (see sharedRuntime_xxx.cpp)
2656   // The checks are inserted only if -XX:+VerifyAdapterCalls is specified.
2657   if (contains_all_checks || !VerifyAdapterCalls) {
2658     assert_lock_strong(AdapterHandlerLibrary_lock);
2659     _adapter_handler_table->put(fingerprint, entry);
2660   }
2661   return entry;
2662 }
2663 
2664 address AdapterHandlerEntry::base_address() {
2665   address base = _i2c_entry;
2666   if (base == nullptr)  base = _c2i_entry;
2667   assert(base <= _c2i_entry || _c2i_entry == nullptr, "");
2668   assert(base <= _c2i_unverified_entry || _c2i_unverified_entry == nullptr, "");
2669   assert(base <= _c2i_no_clinit_check_entry || _c2i_no_clinit_check_entry == nullptr, "");
2670   return base;
2671 }
2672 
2673 void AdapterHandlerEntry::relocate(address new_base) {
2674   address old_base = base_address();
2675   assert(old_base != nullptr, "");
2676   ptrdiff_t delta = new_base - old_base;
2677   if (_i2c_entry != nullptr)
2678     _i2c_entry += delta;
2679   if (_c2i_entry != nullptr)
2680     _c2i_entry += delta;
2681   if (_c2i_unverified_entry != nullptr)
2682     _c2i_unverified_entry += delta;
2683   if (_c2i_no_clinit_check_entry != nullptr)
2684     _c2i_no_clinit_check_entry += delta;
2685   assert(base_address() == new_base, "");
2686 }
2687 
2688 
2689 AdapterHandlerEntry::~AdapterHandlerEntry() {
2690   delete _fingerprint;
2691 #ifdef ASSERT
2692   FREE_C_HEAP_ARRAY(unsigned char, _saved_code);
2693 #endif
2694 }
2695 
2696 
2697 #ifdef ASSERT
2698 // Capture the code before relocation so that it can be compared
2699 // against other versions.  If the code is captured after relocation
2700 // then relative instructions won't be equivalent.
2701 void AdapterHandlerEntry::save_code(unsigned char* buffer, int length) {
2702   _saved_code = NEW_C_HEAP_ARRAY(unsigned char, length, mtCode);
2703   _saved_code_length = length;
2704   memcpy(_saved_code, buffer, length);
2705 }
2706 
2707 
2708 bool AdapterHandlerEntry::compare_code(AdapterHandlerEntry* other) {
2709   assert(_saved_code != nullptr && other->_saved_code != nullptr, "code not saved");
2710 
2711   if (other->_saved_code_length != _saved_code_length) {
2712     return false;
2713   }
2714 
2715   return memcmp(other->_saved_code, _saved_code, _saved_code_length) == 0;
2716 }
2717 #endif
2718 
2719 
2720 /**
2721  * Create a native wrapper for this native method.  The wrapper converts the
2722  * Java-compiled calling convention to the native convention, handles
2723  * arguments, and transitions to native.  On return from the native we transition
2724  * back to java blocking if a safepoint is in progress.
2725  */
2726 void AdapterHandlerLibrary::create_native_wrapper(const methodHandle& method) {
2727   ResourceMark rm;
2728   nmethod* nm = nullptr;
2729 
2730   // Check if memory should be freed before allocation
2731   CodeCache::gc_on_allocation();
2732 
2733   assert(method->is_native(), "must be native");
2734   assert(method->is_special_native_intrinsic() ||
2735          method->has_native_function(), "must have something valid to call!");
2736 
2737   {
2738     // Perform the work while holding the lock, but perform any printing outside the lock
2739     MutexLocker mu(AdapterHandlerLibrary_lock);
2740     // See if somebody beat us to it
2741     if (method->code() != nullptr) {
2742       return;
2743     }
2744 
2745     const int compile_id = CompileBroker::assign_compile_id(method, CompileBroker::standard_entry_bci);
2746     assert(compile_id > 0, "Must generate native wrapper");
2747 
2748 
2749     ResourceMark rm;
2750     BufferBlob*  buf = buffer_blob(); // the temporary code buffer in CodeCache
2751     if (buf != nullptr) {
2752       CodeBuffer buffer(buf);
2753 
2754       if (method->is_continuation_enter_intrinsic()) {
2755         buffer.initialize_stubs_size(192);
2756       }
2757 
2758       struct { double data[20]; } locs_buf;
2759       struct { double data[20]; } stubs_locs_buf;
2760       buffer.insts()->initialize_shared_locs((relocInfo*)&locs_buf, sizeof(locs_buf) / sizeof(relocInfo));
2761 #if defined(AARCH64) || defined(PPC64)
2762       // On AArch64 with ZGC and nmethod entry barriers, we need all oops to be
2763       // in the constant pool to ensure ordering between the barrier and oops
2764       // accesses. For native_wrappers we need a constant.
2765       // On PPC64 the continuation enter intrinsic needs the constant pool for the compiled
2766       // static java call that is resolved in the runtime.
2767       if (PPC64_ONLY(method->is_continuation_enter_intrinsic() &&) true) {
2768         buffer.initialize_consts_size(8 PPC64_ONLY(+ 24));
2769       }
2770 #endif
2771       buffer.stubs()->initialize_shared_locs((relocInfo*)&stubs_locs_buf, sizeof(stubs_locs_buf) / sizeof(relocInfo));
2772       MacroAssembler _masm(&buffer);
2773 
2774       // Fill in the signature array, for the calling-convention call.
2775       const int total_args_passed = method->size_of_parameters();
2776 
2777       VMRegPair stack_regs[16];
2778       VMRegPair* regs = (total_args_passed <= 16) ? stack_regs : NEW_RESOURCE_ARRAY(VMRegPair, total_args_passed);
2779 
2780       AdapterSignatureIterator si(method->signature(), method->constMethod()->fingerprint(),
2781                               method->is_static(), total_args_passed);
2782       BasicType* sig_bt = si.basic_types();
2783       assert(si.slots() == total_args_passed, "");
2784       BasicType ret_type = si.return_type();
2785 
2786       // Now get the compiled-Java arguments layout.
2787       SharedRuntime::java_calling_convention(sig_bt, regs, total_args_passed);
2788 
2789       // Generate the compiled-to-native wrapper code
2790       nm = SharedRuntime::generate_native_wrapper(&_masm, method, compile_id, sig_bt, regs, ret_type);
2791 
2792       if (nm != nullptr) {
2793         {
2794           MutexLocker pl(CompiledMethod_lock, Mutex::_no_safepoint_check_flag);
2795           if (nm->make_in_use()) {
2796             method->set_code(method, nm);
2797           }
2798         }
2799 
2800         DirectiveSet* directive = DirectivesStack::getDefaultDirective(CompileBroker::compiler(CompLevel_simple));
2801         if (directive->PrintAssemblyOption) {
2802           nm->print_code();
2803         }
2804         DirectivesStack::release(directive);
2805       }
2806     }
2807   } // Unlock AdapterHandlerLibrary_lock
2808 
2809 
2810   // Install the generated code.
2811   if (nm != nullptr) {
2812     const char *msg = method->is_static() ? "(static)" : "";
2813     CompileTask::print_ul(nm, msg);
2814     if (PrintCompilation) {
2815       ttyLocker ttyl;
2816       CompileTask::print(tty, nm, msg);
2817     }
2818     nm->post_compiled_method_load_event();
2819   }
2820 }
2821 
2822 // -------------------------------------------------------------------------
2823 // Java-Java calling convention
2824 // (what you use when Java calls Java)
2825 
2826 //------------------------------name_for_receiver----------------------------------
2827 // For a given signature, return the VMReg for parameter 0.
2828 VMReg SharedRuntime::name_for_receiver() {
2829   VMRegPair regs;
2830   BasicType sig_bt = T_OBJECT;
2831   (void) java_calling_convention(&sig_bt, &regs, 1);
2832   // Return argument 0 register.  In the LP64 build pointers
2833   // take 2 registers, but the VM wants only the 'main' name.
2834   return regs.first();
2835 }
2836 
2837 VMRegPair *SharedRuntime::find_callee_arguments(Symbol* sig, bool has_receiver, bool has_appendix, int* arg_size) {
2838   // This method is returning a data structure allocating as a
2839   // ResourceObject, so do not put any ResourceMarks in here.
2840 
2841   BasicType *sig_bt = NEW_RESOURCE_ARRAY(BasicType, 256);
2842   VMRegPair *regs = NEW_RESOURCE_ARRAY(VMRegPair, 256);
2843   int cnt = 0;
2844   if (has_receiver) {
2845     sig_bt[cnt++] = T_OBJECT; // Receiver is argument 0; not in signature
2846   }
2847 
2848   for (SignatureStream ss(sig); !ss.at_return_type(); ss.next()) {
2849     BasicType type = ss.type();
2850     sig_bt[cnt++] = type;
2851     if (is_double_word_type(type))
2852       sig_bt[cnt++] = T_VOID;
2853   }
2854 
2855   if (has_appendix) {
2856     sig_bt[cnt++] = T_OBJECT;
2857   }
2858 
2859   assert(cnt < 256, "grow table size");
2860 
2861   int comp_args_on_stack;
2862   comp_args_on_stack = java_calling_convention(sig_bt, regs, cnt);
2863 
2864   // the calling convention doesn't count out_preserve_stack_slots so
2865   // we must add that in to get "true" stack offsets.
2866 
2867   if (comp_args_on_stack) {
2868     for (int i = 0; i < cnt; i++) {
2869       VMReg reg1 = regs[i].first();
2870       if (reg1->is_stack()) {
2871         // Yuck
2872         reg1 = reg1->bias(out_preserve_stack_slots());
2873       }
2874       VMReg reg2 = regs[i].second();
2875       if (reg2->is_stack()) {
2876         // Yuck
2877         reg2 = reg2->bias(out_preserve_stack_slots());
2878       }
2879       regs[i].set_pair(reg2, reg1);
2880     }
2881   }
2882 
2883   // results
2884   *arg_size = cnt;
2885   return regs;
2886 }
2887 
2888 // OSR Migration Code
2889 //
2890 // This code is used convert interpreter frames into compiled frames.  It is
2891 // called from very start of a compiled OSR nmethod.  A temp array is
2892 // allocated to hold the interesting bits of the interpreter frame.  All
2893 // active locks are inflated to allow them to move.  The displaced headers and
2894 // active interpreter locals are copied into the temp buffer.  Then we return
2895 // back to the compiled code.  The compiled code then pops the current
2896 // interpreter frame off the stack and pushes a new compiled frame.  Then it
2897 // copies the interpreter locals and displaced headers where it wants.
2898 // Finally it calls back to free the temp buffer.
2899 //
2900 // All of this is done NOT at any Safepoint, nor is any safepoint or GC allowed.
2901 
2902 JRT_LEAF(intptr_t*, SharedRuntime::OSR_migration_begin( JavaThread *current) )
2903   assert(current == JavaThread::current(), "pre-condition");
2904 
2905   // During OSR migration, we unwind the interpreted frame and replace it with a compiled
2906   // frame. The stack watermark code below ensures that the interpreted frame is processed
2907   // before it gets unwound. This is helpful as the size of the compiled frame could be
2908   // larger than the interpreted frame, which could result in the new frame not being
2909   // processed correctly.
2910   StackWatermarkSet::before_unwind(current);
2911 
2912   //
2913   // This code is dependent on the memory layout of the interpreter local
2914   // array and the monitors. On all of our platforms the layout is identical
2915   // so this code is shared. If some platform lays the their arrays out
2916   // differently then this code could move to platform specific code or
2917   // the code here could be modified to copy items one at a time using
2918   // frame accessor methods and be platform independent.
2919 
2920   frame fr = current->last_frame();
2921   assert(fr.is_interpreted_frame(), "");
2922   assert(fr.interpreter_frame_expression_stack_size()==0, "only handle empty stacks");
2923 
2924   // Figure out how many monitors are active.
2925   int active_monitor_count = 0;
2926   for (BasicObjectLock *kptr = fr.interpreter_frame_monitor_end();
2927        kptr < fr.interpreter_frame_monitor_begin();
2928        kptr = fr.next_monitor_in_interpreter_frame(kptr) ) {
2929     if (kptr->obj() != nullptr) active_monitor_count++;
2930   }
2931 
2932   // QQQ we could place number of active monitors in the array so that compiled code
2933   // could double check it.
2934 
2935   Method* moop = fr.interpreter_frame_method();
2936   int max_locals = moop->max_locals();
2937   // Allocate temp buffer, 1 word per local & 2 per active monitor
2938   int buf_size_words = max_locals + active_monitor_count * BasicObjectLock::size();
2939   intptr_t *buf = NEW_C_HEAP_ARRAY(intptr_t,buf_size_words, mtCode);
2940 
2941   // Copy the locals.  Order is preserved so that loading of longs works.
2942   // Since there's no GC I can copy the oops blindly.
2943   assert(sizeof(HeapWord)==sizeof(intptr_t), "fix this code");
2944   Copy::disjoint_words((HeapWord*)fr.interpreter_frame_local_at(max_locals-1),
2945                        (HeapWord*)&buf[0],
2946                        max_locals);
2947 
2948   // Inflate locks.  Copy the displaced headers.  Be careful, there can be holes.
2949   int i = max_locals;
2950   for (BasicObjectLock *kptr2 = fr.interpreter_frame_monitor_end();
2951        kptr2 < fr.interpreter_frame_monitor_begin();
2952        kptr2 = fr.next_monitor_in_interpreter_frame(kptr2) ) {
2953     if (kptr2->obj() != nullptr) {         // Avoid 'holes' in the monitor array
2954       BasicLock *lock = kptr2->lock();
2955       if (LockingMode == LM_LEGACY) {
2956         // Inflate so the object's header no longer refers to the BasicLock.
2957         if (lock->displaced_header().is_unlocked()) {
2958           // The object is locked and the resulting ObjectMonitor* will also be
2959           // locked so it can't be async deflated until ownership is dropped.
2960           // See the big comment in basicLock.cpp: BasicLock::move_to().
2961           ObjectSynchronizer::inflate_helper(kptr2->obj());
2962         }
2963         // Now the displaced header is free to move because the
2964         // object's header no longer refers to it.
2965         buf[i] = (intptr_t)lock->displaced_header().value();
2966       }
2967 #ifdef ASSERT
2968       else {
2969         buf[i] = badDispHeaderOSR;
2970       }
2971 #endif
2972       i++;
2973       buf[i++] = cast_from_oop<intptr_t>(kptr2->obj());
2974     }
2975   }
2976   assert(i - max_locals == active_monitor_count*2, "found the expected number of monitors");
2977 
2978   RegisterMap map(current,
2979                   RegisterMap::UpdateMap::skip,
2980                   RegisterMap::ProcessFrames::include,
2981                   RegisterMap::WalkContinuation::skip);
2982   frame sender = fr.sender(&map);
2983   if (sender.is_interpreted_frame()) {
2984     current->push_cont_fastpath(sender.sp());
2985   }
2986 
2987   return buf;
2988 JRT_END
2989 
2990 JRT_LEAF(void, SharedRuntime::OSR_migration_end( intptr_t* buf) )
2991   FREE_C_HEAP_ARRAY(intptr_t, buf);
2992 JRT_END
2993 
2994 bool AdapterHandlerLibrary::contains(const CodeBlob* b) {
2995   bool found = false;
2996   auto findblob = [&] (AdapterFingerPrint* key, AdapterHandlerEntry* a) {
2997     return (found = (b == CodeCache::find_blob(a->get_i2c_entry())));
2998   };
2999   assert_locked_or_safepoint(AdapterHandlerLibrary_lock);
3000   _adapter_handler_table->iterate(findblob);
3001   return found;
3002 }
3003 
3004 void AdapterHandlerLibrary::print_handler_on(outputStream* st, const CodeBlob* b) {
3005   bool found = false;
3006   auto findblob = [&] (AdapterFingerPrint* key, AdapterHandlerEntry* a) {
3007     if (b == CodeCache::find_blob(a->get_i2c_entry())) {
3008       found = true;
3009       st->print("Adapter for signature: ");
3010       a->print_adapter_on(st);
3011       return true;
3012     } else {
3013       return false; // keep looking
3014     }
3015   };
3016   assert_locked_or_safepoint(AdapterHandlerLibrary_lock);
3017   _adapter_handler_table->iterate(findblob);
3018   assert(found, "Should have found handler");
3019 }
3020 
3021 void AdapterHandlerEntry::print_adapter_on(outputStream* st) const {
3022   st->print("AHE@" INTPTR_FORMAT ": %s", p2i(this), fingerprint()->as_string());
3023   if (get_i2c_entry() != nullptr) {
3024     st->print(" i2c: " INTPTR_FORMAT, p2i(get_i2c_entry()));
3025   }
3026   if (get_c2i_entry() != nullptr) {
3027     st->print(" c2i: " INTPTR_FORMAT, p2i(get_c2i_entry()));
3028   }
3029   if (get_c2i_unverified_entry() != nullptr) {
3030     st->print(" c2iUV: " INTPTR_FORMAT, p2i(get_c2i_unverified_entry()));
3031   }
3032   if (get_c2i_no_clinit_check_entry() != nullptr) {
3033     st->print(" c2iNCI: " INTPTR_FORMAT, p2i(get_c2i_no_clinit_check_entry()));
3034   }
3035   st->cr();
3036 }
3037 
3038 #ifndef PRODUCT
3039 
3040 void AdapterHandlerLibrary::print_statistics() {
3041   print_table_statistics();
3042 }
3043 
3044 #endif /* PRODUCT */
3045 
3046 JRT_LEAF(void, SharedRuntime::enable_stack_reserved_zone(JavaThread* current))
3047   assert(current == JavaThread::current(), "pre-condition");
3048   StackOverflow* overflow_state = current->stack_overflow_state();
3049   overflow_state->enable_stack_reserved_zone(/*check_if_disabled*/true);
3050   overflow_state->set_reserved_stack_activation(current->stack_base());
3051 JRT_END
3052 
3053 frame SharedRuntime::look_for_reserved_stack_annotated_method(JavaThread* current, frame fr) {
3054   ResourceMark rm(current);
3055   frame activation;
3056   CompiledMethod* nm = nullptr;
3057   int count = 1;
3058 
3059   assert(fr.is_java_frame(), "Must start on Java frame");
3060 
3061   RegisterMap map(JavaThread::current(),
3062                   RegisterMap::UpdateMap::skip,
3063                   RegisterMap::ProcessFrames::skip,
3064                   RegisterMap::WalkContinuation::skip); // don't walk continuations
3065   for (; !fr.is_first_frame(); fr = fr.sender(&map)) {
3066     if (!fr.is_java_frame()) {
3067       continue;
3068     }
3069 
3070     Method* method = nullptr;
3071     bool found = false;
3072     if (fr.is_interpreted_frame()) {
3073       method = fr.interpreter_frame_method();
3074       if (method != nullptr && method->has_reserved_stack_access()) {
3075         found = true;
3076       }
3077     } else {
3078       CodeBlob* cb = fr.cb();
3079       if (cb != nullptr && cb->is_compiled()) {
3080         nm = cb->as_compiled_method();
3081         method = nm->method();
3082         // scope_desc_near() must be used, instead of scope_desc_at() because on
3083         // SPARC, the pcDesc can be on the delay slot after the call instruction.
3084         for (ScopeDesc *sd = nm->scope_desc_near(fr.pc()); sd != nullptr; sd = sd->sender()) {
3085           method = sd->method();
3086           if (method != nullptr && method->has_reserved_stack_access()) {
3087             found = true;
3088           }
3089         }
3090       }
3091     }
3092     if (found) {
3093       activation = fr;
3094       warning("Potentially dangerous stack overflow in "
3095               "ReservedStackAccess annotated method %s [%d]",
3096               method->name_and_sig_as_C_string(), count++);
3097       EventReservedStackActivation event;
3098       if (event.should_commit()) {
3099         event.set_method(method);
3100         event.commit();
3101       }
3102     }
3103   }
3104   return activation;
3105 }
3106 
3107 void SharedRuntime::on_slowpath_allocation_exit(JavaThread* current) {
3108   // After any safepoint, just before going back to compiled code,
3109   // we inform the GC that we will be doing initializing writes to
3110   // this object in the future without emitting card-marks, so
3111   // GC may take any compensating steps.
3112 
3113   oop new_obj = current->vm_result();
3114   if (new_obj == nullptr) return;
3115 
3116   BarrierSet *bs = BarrierSet::barrier_set();
3117   bs->on_slowpath_allocation_exit(current, new_obj);
3118 }