1 /*
   2  * Copyright (c) 2003, 2026, Oracle and/or its affiliates. All rights reserved.
   3  * Copyright (c) 2014, 2021, Red Hat Inc. All rights reserved.
   4  * Copyright (c) 2021, Azul Systems, Inc. All rights reserved.
   5  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   6  *
   7  * This code is free software; you can redistribute it and/or modify it
   8  * under the terms of the GNU General Public License version 2 only, as
   9  * published by the Free Software Foundation.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  *
  25  */
  26 
  27 #include "asm/macroAssembler.hpp"
  28 #include "asm/macroAssembler.inline.hpp"
  29 #include "code/aotCodeCache.hpp"
  30 #include "code/codeCache.hpp"
  31 #include "code/compiledIC.hpp"
  32 #include "code/debugInfoRec.hpp"
  33 #include "code/vtableStubs.hpp"
  34 #include "compiler/oopMap.hpp"
  35 #include "gc/shared/barrierSetAssembler.hpp"
  36 #include "interpreter/interpreter.hpp"
  37 #include "interpreter/interp_masm.hpp"
  38 #include "logging/log.hpp"
  39 #include "memory/resourceArea.hpp"
  40 #include "nativeInst_aarch64.hpp"
  41 #include "oops/klass.inline.hpp"
  42 #include "oops/method.inline.hpp"
  43 #include "prims/methodHandles.hpp"
  44 #include "runtime/continuation.hpp"
  45 #include "runtime/continuationEntry.inline.hpp"
  46 #include "runtime/globals.hpp"
  47 #include "runtime/jniHandles.hpp"
  48 #include "runtime/safepointMechanism.hpp"
  49 #include "runtime/sharedRuntime.hpp"
  50 #include "runtime/signature.hpp"
  51 #include "runtime/stubRoutines.hpp"
  52 #include "runtime/timerTrace.hpp"
  53 #include "runtime/vframeArray.hpp"
  54 #include "utilities/align.hpp"
  55 #include "utilities/formatBuffer.hpp"
  56 #include "vmreg_aarch64.inline.hpp"
  57 #ifdef COMPILER1
  58 #include "c1/c1_Runtime1.hpp"
  59 #endif
  60 #ifdef COMPILER2
  61 #include "adfiles/ad_aarch64.hpp"
  62 #include "opto/runtime.hpp"
  63 #endif
  64 #if INCLUDE_JVMCI
  65 #include "jvmci/jvmciJavaClasses.hpp"
  66 #endif
  67 
  68 #define __ masm->
  69 
  70 #ifdef PRODUCT
  71 #define BLOCK_COMMENT(str) /* nothing */
  72 #else
  73 #define BLOCK_COMMENT(str) __ block_comment(str)
  74 #endif
  75 
  76 const int StackAlignmentInSlots = StackAlignmentInBytes / VMRegImpl::stack_slot_size;
  77 
  78 // FIXME -- this is used by C1
  79 class RegisterSaver {
  80   const bool _save_vectors;
  81  public:
  82   RegisterSaver(bool save_vectors) : _save_vectors(save_vectors) {}
  83 
  84   OopMap* save_live_registers(MacroAssembler* masm, int additional_frame_words, int* total_frame_words);
  85   void restore_live_registers(MacroAssembler* masm);
  86 
  87   // Offsets into the register save area
  88   // Used by deoptimization when it is managing result register
  89   // values on its own
  90 
  91   int reg_offset_in_bytes(Register r);
  92   int r0_offset_in_bytes()    { return reg_offset_in_bytes(r0); }
  93   int rscratch1_offset_in_bytes()    { return reg_offset_in_bytes(rscratch1); }
  94   int v0_offset_in_bytes();
  95 
  96   // Total stack size in bytes for saving sve predicate registers.
  97   int total_sve_predicate_in_bytes();
  98 
  99   // Capture info about frame layout
 100   // Note this is only correct when not saving full vectors.
 101   enum layout {
 102                 fpu_state_off = 0,
 103                 fpu_state_end = fpu_state_off + FPUStateSizeInWords - 1,
 104                 // The frame sender code expects that rfp will be in
 105                 // the "natural" place and will override any oopMap
 106                 // setting for it. We must therefore force the layout
 107                 // so that it agrees with the frame sender code.
 108                 r0_off = fpu_state_off + FPUStateSizeInWords,
 109                 rfp_off = r0_off + (Register::number_of_registers - 2) * Register::max_slots_per_register,
 110                 return_off = rfp_off + Register::max_slots_per_register,      // slot for return address
 111                 reg_save_size = return_off + Register::max_slots_per_register};
 112 
 113 };
 114 
 115 int RegisterSaver::reg_offset_in_bytes(Register r) {
 116   // The integer registers are located above the floating point
 117   // registers in the stack frame pushed by save_live_registers() so the
 118   // offset depends on whether we are saving full vectors, and whether
 119   // those vectors are NEON or SVE.
 120 
 121   int slots_per_vect = FloatRegister::save_slots_per_register;
 122 
 123 #if COMPILER2_OR_JVMCI
 124   if (_save_vectors) {
 125     slots_per_vect = FloatRegister::slots_per_neon_register;
 126 
 127 #ifdef COMPILER2
 128     if (Matcher::supports_scalable_vector()) {
 129       slots_per_vect = Matcher::scalable_vector_reg_size(T_FLOAT);
 130     }
 131 #endif
 132   }
 133 #endif
 134 
 135   int r0_offset = v0_offset_in_bytes() + (slots_per_vect * FloatRegister::number_of_registers) * BytesPerInt;
 136   return r0_offset + r->encoding() * wordSize;
 137 }
 138 
 139 int RegisterSaver::v0_offset_in_bytes() {
 140   // The floating point registers are located above the predicate registers if
 141   // they are present in the stack frame pushed by save_live_registers(). So the
 142   // offset depends on the saved total predicate vectors in the stack frame.
 143   return (total_sve_predicate_in_bytes() / VMRegImpl::stack_slot_size) * BytesPerInt;
 144 }
 145 
 146 int RegisterSaver::total_sve_predicate_in_bytes() {
 147 #ifdef COMPILER2
 148   if (_save_vectors && Matcher::supports_scalable_vector()) {
 149     return (Matcher::scalable_vector_reg_size(T_BYTE) >> LogBitsPerByte) *
 150            PRegister::number_of_registers;
 151   }
 152 #endif
 153   return 0;
 154 }
 155 
 156 OopMap* RegisterSaver::save_live_registers(MacroAssembler* masm, int additional_frame_words, int* total_frame_words) {
 157   bool use_sve = false;
 158   int sve_vector_size_in_bytes = 0;
 159   int sve_vector_size_in_slots = 0;
 160   int sve_predicate_size_in_slots = 0;
 161   int total_predicate_in_bytes = total_sve_predicate_in_bytes();
 162   int total_predicate_in_slots = total_predicate_in_bytes / VMRegImpl::stack_slot_size;
 163 
 164 #ifdef COMPILER2
 165   use_sve = Matcher::supports_scalable_vector();
 166   if (use_sve) {
 167     sve_vector_size_in_bytes = Matcher::scalable_vector_reg_size(T_BYTE);
 168     sve_vector_size_in_slots = Matcher::scalable_vector_reg_size(T_FLOAT);
 169     sve_predicate_size_in_slots = Matcher::scalable_predicate_reg_slots();
 170   }
 171 #endif
 172 
 173 #if COMPILER2_OR_JVMCI
 174   if (_save_vectors) {
 175     int extra_save_slots_per_register = 0;
 176     // Save upper half of vector registers
 177     if (use_sve) {
 178       extra_save_slots_per_register = sve_vector_size_in_slots - FloatRegister::save_slots_per_register;
 179     } else {
 180       extra_save_slots_per_register = FloatRegister::extra_save_slots_per_neon_register;
 181     }
 182     int extra_vector_bytes = extra_save_slots_per_register *
 183                              VMRegImpl::stack_slot_size *
 184                              FloatRegister::number_of_registers;
 185     additional_frame_words += ((extra_vector_bytes + total_predicate_in_bytes) / wordSize);
 186   }
 187 #else
 188   assert(!_save_vectors, "vectors are generated only by C2 and JVMCI");
 189 #endif
 190 
 191   int frame_size_in_bytes = align_up(additional_frame_words * wordSize +
 192                                      reg_save_size * BytesPerInt, 16);
 193   // OopMap frame size is in compiler stack slots (jint's) not bytes or words
 194   int frame_size_in_slots = frame_size_in_bytes / BytesPerInt;
 195   // The caller will allocate additional_frame_words
 196   int additional_frame_slots = additional_frame_words * wordSize / BytesPerInt;
 197   // CodeBlob frame size is in words.
 198   int frame_size_in_words = frame_size_in_bytes / wordSize;
 199   *total_frame_words = frame_size_in_words;
 200 
 201   // Save Integer and Float registers.
 202   __ enter();
 203   __ push_CPU_state(_save_vectors, use_sve, sve_vector_size_in_bytes, total_predicate_in_bytes);
 204 
 205   // Set an oopmap for the call site.  This oopmap will map all
 206   // oop-registers and debug-info registers as callee-saved.  This
 207   // will allow deoptimization at this safepoint to find all possible
 208   // debug-info recordings, as well as let GC find all oops.
 209 
 210   OopMapSet *oop_maps = new OopMapSet();
 211   OopMap* oop_map = new OopMap(frame_size_in_slots, 0);
 212 
 213   for (int i = 0; i < Register::number_of_registers; i++) {
 214     Register r = as_Register(i);
 215     if (i <= rfp->encoding() && r != rscratch1 && r != rscratch2) {
 216       // SP offsets are in 4-byte words.
 217       // Register slots are 8 bytes wide, 32 floating-point registers.
 218       int sp_offset = Register::max_slots_per_register * i +
 219                       FloatRegister::save_slots_per_register * FloatRegister::number_of_registers;
 220       oop_map->set_callee_saved(VMRegImpl::stack2reg(sp_offset + additional_frame_slots), r->as_VMReg());
 221     }
 222   }
 223 
 224   for (int i = 0; i < FloatRegister::number_of_registers; i++) {
 225     FloatRegister r = as_FloatRegister(i);
 226     int sp_offset = 0;
 227     if (_save_vectors) {
 228       sp_offset = use_sve ? (total_predicate_in_slots + sve_vector_size_in_slots * i) :
 229                             (FloatRegister::slots_per_neon_register * i);
 230     } else {
 231       sp_offset = FloatRegister::save_slots_per_register * i;
 232     }
 233     oop_map->set_callee_saved(VMRegImpl::stack2reg(sp_offset), r->as_VMReg());
 234   }
 235 
 236   return oop_map;
 237 }
 238 
 239 void RegisterSaver::restore_live_registers(MacroAssembler* masm) {
 240 #ifdef COMPILER2
 241   __ pop_CPU_state(_save_vectors, Matcher::supports_scalable_vector(),
 242                    Matcher::scalable_vector_reg_size(T_BYTE), total_sve_predicate_in_bytes());
 243 #else
 244 #if !INCLUDE_JVMCI
 245   assert(!_save_vectors, "vectors are generated only by C2 and JVMCI");
 246 #endif
 247   __ pop_CPU_state(_save_vectors);
 248 #endif
 249   __ ldp(rfp, lr, Address(__ post(sp, 2 * wordSize)));
 250   __ authenticate_return_address();
 251 }
 252 
 253 // Is vector's size (in bytes) bigger than a size saved by default?
 254 // 8 bytes vector registers are saved by default on AArch64.
 255 // The SVE supported min vector size is 8 bytes and we need to save
 256 // predicate registers when the vector size is 8 bytes as well.
 257 bool SharedRuntime::is_wide_vector(int size) {
 258   return size > 8 || (UseSVE > 0 && size >= 8);
 259 }
 260 
 261 // ---------------------------------------------------------------------------
 262 // Read the array of BasicTypes from a signature, and compute where the
 263 // arguments should go.  Values in the VMRegPair regs array refer to 4-byte
 264 // quantities.  Values less than VMRegImpl::stack0 are registers, those above
 265 // refer to 4-byte stack slots.  All stack slots are based off of the stack pointer
 266 // as framesizes are fixed.
 267 // VMRegImpl::stack0 refers to the first slot 0(sp).
 268 // and VMRegImpl::stack0+1 refers to the memory word 4-byes higher.
 269 // Register up to Register::number_of_registers are the 64-bit
 270 // integer registers.
 271 
 272 // Note: the INPUTS in sig_bt are in units of Java argument words,
 273 // which are 64-bit.  The OUTPUTS are in 32-bit units.
 274 
 275 // The Java calling convention is a "shifted" version of the C ABI.
 276 // By skipping the first C ABI register we can call non-static jni
 277 // methods with small numbers of arguments without having to shuffle
 278 // the arguments at all. Since we control the java ABI we ought to at
 279 // least get some advantage out of it.
 280 
 281 int SharedRuntime::java_calling_convention(const BasicType *sig_bt,
 282                                            VMRegPair *regs,
 283                                            int total_args_passed) {
 284 
 285   // Create the mapping between argument positions and
 286   // registers.
 287   static const Register INT_ArgReg[Argument::n_int_register_parameters_j] = {
 288     j_rarg0, j_rarg1, j_rarg2, j_rarg3, j_rarg4, j_rarg5, j_rarg6, j_rarg7
 289   };
 290   static const FloatRegister FP_ArgReg[Argument::n_float_register_parameters_j] = {
 291     j_farg0, j_farg1, j_farg2, j_farg3,
 292     j_farg4, j_farg5, j_farg6, j_farg7
 293   };
 294 
 295 
 296   uint int_args = 0;
 297   uint fp_args = 0;
 298   uint stk_args = 0;
 299 
 300   for (int i = 0; i < total_args_passed; i++) {
 301     switch (sig_bt[i]) {
 302     case T_BOOLEAN:
 303     case T_CHAR:
 304     case T_BYTE:
 305     case T_SHORT:
 306     case T_INT:
 307       if (int_args < Argument::n_int_register_parameters_j) {
 308         regs[i].set1(INT_ArgReg[int_args++]->as_VMReg());
 309       } else {
 310         stk_args = align_up(stk_args, 2);
 311         regs[i].set1(VMRegImpl::stack2reg(stk_args));
 312         stk_args += 1;
 313       }
 314       break;
 315     case T_VOID:
 316       // halves of T_LONG or T_DOUBLE
 317       assert(i != 0 && (sig_bt[i - 1] == T_LONG || sig_bt[i - 1] == T_DOUBLE), "expecting half");
 318       regs[i].set_bad();
 319       break;
 320     case T_LONG:
 321       assert((i + 1) < total_args_passed && sig_bt[i + 1] == T_VOID, "expecting half");
 322       // fall through
 323     case T_OBJECT:
 324     case T_ARRAY:
 325     case T_ADDRESS:
 326       if (int_args < Argument::n_int_register_parameters_j) {
 327         regs[i].set2(INT_ArgReg[int_args++]->as_VMReg());
 328       } else {
 329         stk_args = align_up(stk_args, 2);
 330         regs[i].set2(VMRegImpl::stack2reg(stk_args));
 331         stk_args += 2;
 332       }
 333       break;
 334     case T_FLOAT:
 335       if (fp_args < Argument::n_float_register_parameters_j) {
 336         regs[i].set1(FP_ArgReg[fp_args++]->as_VMReg());
 337       } else {
 338         stk_args = align_up(stk_args, 2);
 339         regs[i].set1(VMRegImpl::stack2reg(stk_args));
 340         stk_args += 1;
 341       }
 342       break;
 343     case T_DOUBLE:
 344       assert((i + 1) < total_args_passed && sig_bt[i + 1] == T_VOID, "expecting half");
 345       if (fp_args < Argument::n_float_register_parameters_j) {
 346         regs[i].set2(FP_ArgReg[fp_args++]->as_VMReg());
 347       } else {
 348         stk_args = align_up(stk_args, 2);
 349         regs[i].set2(VMRegImpl::stack2reg(stk_args));
 350         stk_args += 2;
 351       }
 352       break;
 353     default:
 354       ShouldNotReachHere();
 355       break;
 356     }
 357   }
 358 
 359   return stk_args;
 360 }
 361 
 362 // Patch the callers callsite with entry to compiled code if it exists.
 363 static void patch_callers_callsite(MacroAssembler *masm) {
 364   Label L;
 365   __ ldr(rscratch1, Address(rmethod, in_bytes(Method::code_offset())));
 366   __ cbz(rscratch1, L);
 367 
 368   __ enter();
 369   __ push_CPU_state();
 370 
 371   // VM needs caller's callsite
 372   // VM needs target method
 373   // This needs to be a long call since we will relocate this adapter to
 374   // the codeBuffer and it may not reach
 375 
 376 #ifndef PRODUCT
 377   assert(frame::arg_reg_save_area_bytes == 0, "not expecting frame reg save area");
 378 #endif
 379 
 380   __ mov(c_rarg0, rmethod);
 381   __ mov(c_rarg1, lr);
 382   __ authenticate_return_address(c_rarg1);
 383   __ lea(rscratch1, RuntimeAddress(CAST_FROM_FN_PTR(address, SharedRuntime::fixup_callers_callsite)));
 384   __ blr(rscratch1);
 385 
 386   // Explicit isb required because fixup_callers_callsite may change the code
 387   // stream.
 388   __ safepoint_isb();
 389 
 390   __ pop_CPU_state();
 391   // restore sp
 392   __ leave();
 393   __ bind(L);
 394 }
 395 
 396 static void gen_c2i_adapter(MacroAssembler *masm,
 397                             int total_args_passed,
 398                             int comp_args_on_stack,
 399                             const BasicType *sig_bt,
 400                             const VMRegPair *regs,
 401                             Label& skip_fixup) {
 402   // Before we get into the guts of the C2I adapter, see if we should be here
 403   // at all.  We've come from compiled code and are attempting to jump to the
 404   // interpreter, which means the caller made a static call to get here
 405   // (vcalls always get a compiled target if there is one).  Check for a
 406   // compiled target.  If there is one, we need to patch the caller's call.
 407   patch_callers_callsite(masm);
 408 
 409   __ bind(skip_fixup);
 410 
 411   int words_pushed = 0;
 412 
 413   // Since all args are passed on the stack, total_args_passed *
 414   // Interpreter::stackElementSize is the space we need.
 415 
 416   int extraspace = total_args_passed * Interpreter::stackElementSize;
 417 
 418   __ mov(r19_sender_sp, sp);
 419 
 420   // stack is aligned, keep it that way
 421   extraspace = align_up(extraspace, 2*wordSize);
 422 
 423   if (extraspace)
 424     __ sub(sp, sp, extraspace);
 425 
 426   // Now write the args into the outgoing interpreter space
 427   for (int i = 0; i < total_args_passed; i++) {
 428     if (sig_bt[i] == T_VOID) {
 429       assert(i > 0 && (sig_bt[i-1] == T_LONG || sig_bt[i-1] == T_DOUBLE), "missing half");
 430       continue;
 431     }
 432 
 433     // offset to start parameters
 434     int st_off   = (total_args_passed - i - 1) * Interpreter::stackElementSize;
 435     int next_off = st_off - Interpreter::stackElementSize;
 436 
 437     // Say 4 args:
 438     // i   st_off
 439     // 0   32 T_LONG
 440     // 1   24 T_VOID
 441     // 2   16 T_OBJECT
 442     // 3    8 T_BOOL
 443     // -    0 return address
 444     //
 445     // However to make thing extra confusing. Because we can fit a Java long/double in
 446     // a single slot on a 64 bt vm and it would be silly to break them up, the interpreter
 447     // leaves one slot empty and only stores to a single slot. In this case the
 448     // slot that is occupied is the T_VOID slot. See I said it was confusing.
 449 
 450     VMReg r_1 = regs[i].first();
 451     VMReg r_2 = regs[i].second();
 452     if (!r_1->is_valid()) {
 453       assert(!r_2->is_valid(), "");
 454       continue;
 455     }
 456     if (r_1->is_stack()) {
 457       // memory to memory use rscratch1
 458       int ld_off = (r_1->reg2stack() * VMRegImpl::stack_slot_size
 459                     + extraspace
 460                     + words_pushed * wordSize);
 461       if (!r_2->is_valid()) {
 462         // sign extend??
 463         __ ldrw(rscratch1, Address(sp, ld_off));
 464         __ str(rscratch1, Address(sp, st_off));
 465 
 466       } else {
 467 
 468         __ ldr(rscratch1, Address(sp, ld_off));
 469 
 470         // Two VMREgs|OptoRegs can be T_OBJECT, T_ADDRESS, T_DOUBLE, T_LONG
 471         // T_DOUBLE and T_LONG use two slots in the interpreter
 472         if ( sig_bt[i] == T_LONG || sig_bt[i] == T_DOUBLE) {
 473           // ld_off == LSW, ld_off+wordSize == MSW
 474           // st_off == MSW, next_off == LSW
 475           __ str(rscratch1, Address(sp, next_off));
 476 #ifdef ASSERT
 477           // Overwrite the unused slot with known junk
 478           __ mov(rscratch1, (uint64_t)0xdeadffffdeadaaaaull);
 479           __ str(rscratch1, Address(sp, st_off));
 480 #endif /* ASSERT */
 481         } else {
 482           __ str(rscratch1, Address(sp, st_off));
 483         }
 484       }
 485     } else if (r_1->is_Register()) {
 486       Register r = r_1->as_Register();
 487       if (!r_2->is_valid()) {
 488         // must be only an int (or less ) so move only 32bits to slot
 489         // why not sign extend??
 490         __ str(r, Address(sp, st_off));
 491       } else {
 492         // Two VMREgs|OptoRegs can be T_OBJECT, T_ADDRESS, T_DOUBLE, T_LONG
 493         // T_DOUBLE and T_LONG use two slots in the interpreter
 494         if ( sig_bt[i] == T_LONG || sig_bt[i] == T_DOUBLE) {
 495           // jlong/double in gpr
 496 #ifdef ASSERT
 497           // Overwrite the unused slot with known junk
 498           __ mov(rscratch1, (uint64_t)0xdeadffffdeadaaabull);
 499           __ str(rscratch1, Address(sp, st_off));
 500 #endif /* ASSERT */
 501           __ str(r, Address(sp, next_off));
 502         } else {
 503           __ str(r, Address(sp, st_off));
 504         }
 505       }
 506     } else {
 507       assert(r_1->is_FloatRegister(), "");
 508       if (!r_2->is_valid()) {
 509         // only a float use just part of the slot
 510         __ strs(r_1->as_FloatRegister(), Address(sp, st_off));
 511       } else {
 512 #ifdef ASSERT
 513         // Overwrite the unused slot with known junk
 514         __ mov(rscratch1, (uint64_t)0xdeadffffdeadaaacull);
 515         __ str(rscratch1, Address(sp, st_off));
 516 #endif /* ASSERT */
 517         __ strd(r_1->as_FloatRegister(), Address(sp, next_off));
 518       }
 519     }
 520   }
 521 
 522   __ mov(esp, sp); // Interp expects args on caller's expression stack
 523 
 524   __ ldr(rscratch1, Address(rmethod, in_bytes(Method::interpreter_entry_offset())));
 525   __ br(rscratch1);
 526 }
 527 
 528 
 529 void SharedRuntime::gen_i2c_adapter(MacroAssembler *masm,
 530                                     int total_args_passed,
 531                                     int comp_args_on_stack,
 532                                     const BasicType *sig_bt,
 533                                     const VMRegPair *regs) {
 534 
 535   // Note: r19_sender_sp contains the senderSP on entry. We must
 536   // preserve it since we may do a i2c -> c2i transition if we lose a
 537   // race where compiled code goes non-entrant while we get args
 538   // ready.
 539 
 540   // Adapters are frameless.
 541 
 542   // An i2c adapter is frameless because the *caller* frame, which is
 543   // interpreted, routinely repairs its own esp (from
 544   // interpreter_frame_last_sp), even if a callee has modified the
 545   // stack pointer.  It also recalculates and aligns sp.
 546 
 547   // A c2i adapter is frameless because the *callee* frame, which is
 548   // interpreted, routinely repairs its caller's sp (from sender_sp,
 549   // which is set up via the senderSP register).
 550 
 551   // In other words, if *either* the caller or callee is interpreted, we can
 552   // get the stack pointer repaired after a call.
 553 
 554   // This is why c2i and i2c adapters cannot be indefinitely composed.
 555   // In particular, if a c2i adapter were to somehow call an i2c adapter,
 556   // both caller and callee would be compiled methods, and neither would
 557   // clean up the stack pointer changes performed by the two adapters.
 558   // If this happens, control eventually transfers back to the compiled
 559   // caller, but with an uncorrected stack, causing delayed havoc.
 560 
 561   // Cut-out for having no stack args.
 562   int comp_words_on_stack = align_up(comp_args_on_stack*VMRegImpl::stack_slot_size, wordSize)>>LogBytesPerWord;
 563   if (comp_args_on_stack) {
 564     __ sub(rscratch1, sp, comp_words_on_stack * wordSize);
 565     __ andr(sp, rscratch1, -16);
 566   }
 567 
 568   // Will jump to the compiled code just as if compiled code was doing it.
 569   // Pre-load the register-jump target early, to schedule it better.
 570   __ ldr(rscratch1, Address(rmethod, in_bytes(Method::from_compiled_offset())));
 571 
 572 #if INCLUDE_JVMCI
 573   if (EnableJVMCI) {
 574     // check if this call should be routed towards a specific entry point
 575     __ ldr(rscratch2, Address(rthread, in_bytes(JavaThread::jvmci_alternate_call_target_offset())));
 576     Label no_alternative_target;
 577     __ cbz(rscratch2, no_alternative_target);
 578     __ mov(rscratch1, rscratch2);
 579     __ str(zr, Address(rthread, in_bytes(JavaThread::jvmci_alternate_call_target_offset())));
 580     __ bind(no_alternative_target);
 581   }
 582 #endif // INCLUDE_JVMCI
 583 
 584   // Now generate the shuffle code.
 585   for (int i = 0; i < total_args_passed; i++) {
 586     if (sig_bt[i] == T_VOID) {
 587       assert(i > 0 && (sig_bt[i-1] == T_LONG || sig_bt[i-1] == T_DOUBLE), "missing half");
 588       continue;
 589     }
 590 
 591     // Pick up 0, 1 or 2 words from SP+offset.
 592 
 593     assert(!regs[i].second()->is_valid() || regs[i].first()->next() == regs[i].second(),
 594             "scrambled load targets?");
 595     // Load in argument order going down.
 596     int ld_off = (total_args_passed - i - 1)*Interpreter::stackElementSize;
 597     // Point to interpreter value (vs. tag)
 598     int next_off = ld_off - Interpreter::stackElementSize;
 599     //
 600     //
 601     //
 602     VMReg r_1 = regs[i].first();
 603     VMReg r_2 = regs[i].second();
 604     if (!r_1->is_valid()) {
 605       assert(!r_2->is_valid(), "");
 606       continue;
 607     }
 608     if (r_1->is_stack()) {
 609       // Convert stack slot to an SP offset (+ wordSize to account for return address )
 610       int st_off = regs[i].first()->reg2stack()*VMRegImpl::stack_slot_size;
 611       if (!r_2->is_valid()) {
 612         // sign extend???
 613         __ ldrsw(rscratch2, Address(esp, ld_off));
 614         __ str(rscratch2, Address(sp, st_off));
 615       } else {
 616         //
 617         // We are using two optoregs. This can be either T_OBJECT,
 618         // T_ADDRESS, T_LONG, or T_DOUBLE the interpreter allocates
 619         // two slots but only uses one for thr T_LONG or T_DOUBLE case
 620         // So we must adjust where to pick up the data to match the
 621         // interpreter.
 622         //
 623         // Interpreter local[n] == MSW, local[n+1] == LSW however locals
 624         // are accessed as negative so LSW is at LOW address
 625 
 626         // ld_off is MSW so get LSW
 627         const int offset = (sig_bt[i]==T_LONG||sig_bt[i]==T_DOUBLE)?
 628                            next_off : ld_off;
 629         __ ldr(rscratch2, Address(esp, offset));
 630         // st_off is LSW (i.e. reg.first())
 631         __ str(rscratch2, Address(sp, st_off));
 632       }
 633     } else if (r_1->is_Register()) {  // Register argument
 634       Register r = r_1->as_Register();
 635       if (r_2->is_valid()) {
 636         //
 637         // We are using two VMRegs. This can be either T_OBJECT,
 638         // T_ADDRESS, T_LONG, or T_DOUBLE the interpreter allocates
 639         // two slots but only uses one for thr T_LONG or T_DOUBLE case
 640         // So we must adjust where to pick up the data to match the
 641         // interpreter.
 642 
 643         const int offset = (sig_bt[i]==T_LONG||sig_bt[i]==T_DOUBLE)?
 644                            next_off : ld_off;
 645 
 646         // this can be a misaligned move
 647         __ ldr(r, Address(esp, offset));
 648       } else {
 649         // sign extend and use a full word?
 650         __ ldrw(r, Address(esp, ld_off));
 651       }
 652     } else {
 653       if (!r_2->is_valid()) {
 654         __ ldrs(r_1->as_FloatRegister(), Address(esp, ld_off));
 655       } else {
 656         __ ldrd(r_1->as_FloatRegister(), Address(esp, next_off));
 657       }
 658     }
 659   }
 660 
 661   __ mov(rscratch2, rscratch1);
 662   __ push_cont_fastpath(rthread); // Set JavaThread::_cont_fastpath to the sp of the oldest interpreted frame we know about; kills rscratch1
 663   __ mov(rscratch1, rscratch2);
 664 
 665   // 6243940 We might end up in handle_wrong_method if
 666   // the callee is deoptimized as we race thru here. If that
 667   // happens we don't want to take a safepoint because the
 668   // caller frame will look interpreted and arguments are now
 669   // "compiled" so it is much better to make this transition
 670   // invisible to the stack walking code. Unfortunately if
 671   // we try and find the callee by normal means a safepoint
 672   // is possible. So we stash the desired callee in the thread
 673   // and the vm will find there should this case occur.
 674 
 675   __ str(rmethod, Address(rthread, JavaThread::callee_target_offset()));
 676 
 677   __ br(rscratch1);
 678 }
 679 
 680 // ---------------------------------------------------------------
 681 void SharedRuntime::generate_i2c2i_adapters(MacroAssembler *masm,
 682                                             int total_args_passed,
 683                                             int comp_args_on_stack,
 684                                             const BasicType *sig_bt,
 685                                             const VMRegPair *regs,
 686                                             address entry_address[AdapterBlob::ENTRY_COUNT]) {
 687   entry_address[AdapterBlob::I2C] = __ pc();
 688 
 689   gen_i2c_adapter(masm, total_args_passed, comp_args_on_stack, sig_bt, regs);
 690 
 691   entry_address[AdapterBlob::C2I_Unverified] = __ pc();
 692   Label skip_fixup;
 693 
 694   Register data = rscratch2;
 695   Register receiver = j_rarg0;
 696   Register tmp = r10;  // A call-clobbered register not used for arg passing
 697 
 698   // -------------------------------------------------------------------------
 699   // Generate a C2I adapter.  On entry we know rmethod holds the Method* during calls
 700   // to the interpreter.  The args start out packed in the compiled layout.  They
 701   // need to be unpacked into the interpreter layout.  This will almost always
 702   // require some stack space.  We grow the current (compiled) stack, then repack
 703   // the args.  We  finally end in a jump to the generic interpreter entry point.
 704   // On exit from the interpreter, the interpreter will restore our SP (lest the
 705   // compiled code, which relies solely on SP and not FP, get sick).
 706 
 707   {
 708     __ block_comment("c2i_unverified_entry {");
 709     // Method might have been compiled since the call site was patched to
 710     // interpreted; if that is the case treat it as a miss so we can get
 711     // the call site corrected.
 712     __ ic_check(1 /* end_alignment */);
 713     __ ldr(rmethod, Address(data, CompiledICData::speculated_method_offset()));
 714 
 715     __ ldr(rscratch1, Address(rmethod, in_bytes(Method::code_offset())));
 716     __ cbz(rscratch1, skip_fixup);
 717     __ far_jump(RuntimeAddress(SharedRuntime::get_ic_miss_stub()));
 718     __ block_comment("} c2i_unverified_entry");
 719   }
 720 
 721   entry_address[AdapterBlob::C2I] = __ pc();
 722 
 723   // Class initialization barrier for static methods
 724   entry_address[AdapterBlob::C2I_No_Clinit_Check] = nullptr;
 725   assert(VM_Version::supports_fast_class_init_checks(), "sanity");
 726   Label L_skip_barrier;
 727 
 728   // Bypass the barrier for non-static methods
 729   __ ldrh(rscratch1, Address(rmethod, Method::access_flags_offset()));
 730   __ andsw(zr, rscratch1, JVM_ACC_STATIC);
 731   __ br(Assembler::EQ, L_skip_barrier); // non-static
 732 
 733   __ load_method_holder(rscratch2, rmethod);
 734   __ clinit_barrier(rscratch2, rscratch1, &L_skip_barrier);
 735   __ far_jump(RuntimeAddress(SharedRuntime::get_handle_wrong_method_stub()));
 736 
 737   __ bind(L_skip_barrier);
 738   entry_address[AdapterBlob::C2I_No_Clinit_Check] = __ pc();
 739 
 740   BarrierSetAssembler* bs = BarrierSet::barrier_set()->barrier_set_assembler();
 741   bs->c2i_entry_barrier(masm);
 742 
 743   gen_c2i_adapter(masm, total_args_passed, comp_args_on_stack, sig_bt, regs, skip_fixup);
 744   return;
 745 }
 746 
 747 static int c_calling_convention_priv(const BasicType *sig_bt,
 748                                          VMRegPair *regs,
 749                                          int total_args_passed) {
 750 
 751 // We return the amount of VMRegImpl stack slots we need to reserve for all
 752 // the arguments NOT counting out_preserve_stack_slots.
 753 
 754     static const Register INT_ArgReg[Argument::n_int_register_parameters_c] = {
 755       c_rarg0, c_rarg1, c_rarg2, c_rarg3, c_rarg4, c_rarg5,  c_rarg6,  c_rarg7
 756     };
 757     static const FloatRegister FP_ArgReg[Argument::n_float_register_parameters_c] = {
 758       c_farg0, c_farg1, c_farg2, c_farg3,
 759       c_farg4, c_farg5, c_farg6, c_farg7
 760     };
 761 
 762     uint int_args = 0;
 763     uint fp_args = 0;
 764     uint stk_args = 0; // inc by 2 each time
 765 
 766     for (int i = 0; i < total_args_passed; i++) {
 767       switch (sig_bt[i]) {
 768       case T_BOOLEAN:
 769       case T_CHAR:
 770       case T_BYTE:
 771       case T_SHORT:
 772       case T_INT:
 773         if (int_args < Argument::n_int_register_parameters_c) {
 774           regs[i].set1(INT_ArgReg[int_args++]->as_VMReg());
 775         } else {
 776 #ifdef __APPLE__
 777           // Less-than word types are stored one after another.
 778           // The code is unable to handle this so bailout.
 779           return -1;
 780 #endif
 781           regs[i].set1(VMRegImpl::stack2reg(stk_args));
 782           stk_args += 2;
 783         }
 784         break;
 785       case T_LONG:
 786         assert((i + 1) < total_args_passed && sig_bt[i + 1] == T_VOID, "expecting half");
 787         // fall through
 788       case T_OBJECT:
 789       case T_ARRAY:
 790       case T_ADDRESS:
 791       case T_METADATA:
 792         if (int_args < Argument::n_int_register_parameters_c) {
 793           regs[i].set2(INT_ArgReg[int_args++]->as_VMReg());
 794         } else {
 795           regs[i].set2(VMRegImpl::stack2reg(stk_args));
 796           stk_args += 2;
 797         }
 798         break;
 799       case T_FLOAT:
 800         if (fp_args < Argument::n_float_register_parameters_c) {
 801           regs[i].set1(FP_ArgReg[fp_args++]->as_VMReg());
 802         } else {
 803 #ifdef __APPLE__
 804           // Less-than word types are stored one after another.
 805           // The code is unable to handle this so bailout.
 806           return -1;
 807 #endif
 808           regs[i].set1(VMRegImpl::stack2reg(stk_args));
 809           stk_args += 2;
 810         }
 811         break;
 812       case T_DOUBLE:
 813         assert((i + 1) < total_args_passed && sig_bt[i + 1] == T_VOID, "expecting half");
 814         if (fp_args < Argument::n_float_register_parameters_c) {
 815           regs[i].set2(FP_ArgReg[fp_args++]->as_VMReg());
 816         } else {
 817           regs[i].set2(VMRegImpl::stack2reg(stk_args));
 818           stk_args += 2;
 819         }
 820         break;
 821       case T_VOID: // Halves of longs and doubles
 822         assert(i != 0 && (sig_bt[i - 1] == T_LONG || sig_bt[i - 1] == T_DOUBLE), "expecting half");
 823         regs[i].set_bad();
 824         break;
 825       default:
 826         ShouldNotReachHere();
 827         break;
 828       }
 829     }
 830 
 831   return stk_args;
 832 }
 833 
 834 int SharedRuntime::vector_calling_convention(VMRegPair *regs,
 835                                              uint num_bits,
 836                                              uint total_args_passed) {
 837   // More than 8 argument inputs are not supported now.
 838   assert(total_args_passed <= Argument::n_float_register_parameters_c, "unsupported");
 839   assert(num_bits >= 64 && num_bits <= 2048 && is_power_of_2(num_bits), "unsupported");
 840 
 841   static const FloatRegister VEC_ArgReg[Argument::n_float_register_parameters_c] = {
 842     v0, v1, v2, v3, v4, v5, v6, v7
 843   };
 844 
 845   // On SVE, we use the same vector registers with 128-bit vector registers on NEON.
 846   int next_reg_val = num_bits == 64 ? 1 : 3;
 847   for (uint i = 0; i < total_args_passed; i++) {
 848     VMReg vmreg = VEC_ArgReg[i]->as_VMReg();
 849     regs[i].set_pair(vmreg->next(next_reg_val), vmreg);
 850   }
 851   return 0;
 852 }
 853 
 854 int SharedRuntime::c_calling_convention(const BasicType *sig_bt,
 855                                          VMRegPair *regs,
 856                                          int total_args_passed)
 857 {
 858   int result = c_calling_convention_priv(sig_bt, regs, total_args_passed);
 859   guarantee(result >= 0, "Unsupported arguments configuration");
 860   return result;
 861 }
 862 
 863 
 864 void SharedRuntime::save_native_result(MacroAssembler *masm, BasicType ret_type, int frame_slots) {
 865   // We always ignore the frame_slots arg and just use the space just below frame pointer
 866   // which by this time is free to use
 867   switch (ret_type) {
 868   case T_FLOAT:
 869     __ strs(v0, Address(rfp, -wordSize));
 870     break;
 871   case T_DOUBLE:
 872     __ strd(v0, Address(rfp, -wordSize));
 873     break;
 874   case T_VOID:  break;
 875   default: {
 876     __ str(r0, Address(rfp, -wordSize));
 877     }
 878   }
 879 }
 880 
 881 void SharedRuntime::restore_native_result(MacroAssembler *masm, BasicType ret_type, int frame_slots) {
 882   // We always ignore the frame_slots arg and just use the space just below frame pointer
 883   // which by this time is free to use
 884   switch (ret_type) {
 885   case T_FLOAT:
 886     __ ldrs(v0, Address(rfp, -wordSize));
 887     break;
 888   case T_DOUBLE:
 889     __ ldrd(v0, Address(rfp, -wordSize));
 890     break;
 891   case T_VOID:  break;
 892   default: {
 893     __ ldr(r0, Address(rfp, -wordSize));
 894     }
 895   }
 896 }
 897 static void save_args(MacroAssembler *masm, int arg_count, int first_arg, VMRegPair *args) {
 898   RegSet x;
 899   for ( int i = first_arg ; i < arg_count ; i++ ) {
 900     if (args[i].first()->is_Register()) {
 901       x = x + args[i].first()->as_Register();
 902     } else if (args[i].first()->is_FloatRegister()) {
 903       __ strd(args[i].first()->as_FloatRegister(), Address(__ pre(sp, -2 * wordSize)));
 904     }
 905   }
 906   __ push(x, sp);
 907 }
 908 
 909 static void restore_args(MacroAssembler *masm, int arg_count, int first_arg, VMRegPair *args) {
 910   RegSet x;
 911   for ( int i = first_arg ; i < arg_count ; i++ ) {
 912     if (args[i].first()->is_Register()) {
 913       x = x + args[i].first()->as_Register();
 914     } else {
 915       ;
 916     }
 917   }
 918   __ pop(x, sp);
 919   for ( int i = arg_count - 1 ; i >= first_arg ; i-- ) {
 920     if (args[i].first()->is_Register()) {
 921       ;
 922     } else if (args[i].first()->is_FloatRegister()) {
 923       __ ldrd(args[i].first()->as_FloatRegister(), Address(__ post(sp, 2 * wordSize)));
 924     }
 925   }
 926 }
 927 
 928 static void verify_oop_args(MacroAssembler* masm,
 929                             const methodHandle& method,
 930                             const BasicType* sig_bt,
 931                             const VMRegPair* regs) {
 932   Register temp_reg = r19;  // not part of any compiled calling seq
 933   if (VerifyOops) {
 934     for (int i = 0; i < method->size_of_parameters(); i++) {
 935       if (sig_bt[i] == T_OBJECT ||
 936           sig_bt[i] == T_ARRAY) {
 937         VMReg r = regs[i].first();
 938         assert(r->is_valid(), "bad oop arg");
 939         if (r->is_stack()) {
 940           __ ldr(temp_reg, Address(sp, r->reg2stack() * VMRegImpl::stack_slot_size));
 941           __ verify_oop(temp_reg);
 942         } else {
 943           __ verify_oop(r->as_Register());
 944         }
 945       }
 946     }
 947   }
 948 }
 949 
 950 // on exit, sp points to the ContinuationEntry
 951 static OopMap* continuation_enter_setup(MacroAssembler* masm, int& stack_slots) {
 952   assert(ContinuationEntry::size() % VMRegImpl::stack_slot_size == 0, "");
 953   assert(in_bytes(ContinuationEntry::cont_offset())  % VMRegImpl::stack_slot_size == 0, "");
 954   assert(in_bytes(ContinuationEntry::chunk_offset()) % VMRegImpl::stack_slot_size == 0, "");
 955 
 956   stack_slots += (int)ContinuationEntry::size()/wordSize;
 957   __ sub(sp, sp, (int)ContinuationEntry::size()); // place Continuation metadata
 958 
 959   OopMap* map = new OopMap(((int)ContinuationEntry::size() + wordSize)/ VMRegImpl::stack_slot_size, 0 /* arg_slots*/);
 960 
 961   __ ldr(rscratch1, Address(rthread, JavaThread::cont_entry_offset()));
 962   __ str(rscratch1, Address(sp, ContinuationEntry::parent_offset()));
 963   __ mov(rscratch1, sp); // we can't use sp as the source in str
 964   __ str(rscratch1, Address(rthread, JavaThread::cont_entry_offset()));
 965 
 966   return map;
 967 }
 968 
 969 // on entry c_rarg1 points to the continuation
 970 //          sp points to ContinuationEntry
 971 //          c_rarg3 -- isVirtualThread
 972 static void fill_continuation_entry(MacroAssembler* masm) {
 973 #ifdef ASSERT
 974   __ movw(rscratch1, ContinuationEntry::cookie_value());
 975   __ strw(rscratch1, Address(sp, ContinuationEntry::cookie_offset()));
 976 #endif
 977 
 978   __ str (c_rarg1, Address(sp, ContinuationEntry::cont_offset()));
 979   __ strw(c_rarg3, Address(sp, ContinuationEntry::flags_offset()));
 980   __ str (zr,      Address(sp, ContinuationEntry::chunk_offset()));
 981   __ strw(zr,      Address(sp, ContinuationEntry::argsize_offset()));
 982   __ strw(zr,      Address(sp, ContinuationEntry::pin_count_offset()));
 983 
 984   __ ldr(rscratch1, Address(rthread, JavaThread::cont_fastpath_offset()));
 985   __ str(rscratch1, Address(sp, ContinuationEntry::parent_cont_fastpath_offset()));
 986 
 987   __ str(zr, Address(rthread, JavaThread::cont_fastpath_offset()));
 988 }
 989 
 990 // on entry, sp points to the ContinuationEntry
 991 // on exit, rfp points to the spilled rfp in the entry frame
 992 static void continuation_enter_cleanup(MacroAssembler* masm) {
 993 #ifndef PRODUCT
 994   Label OK;
 995   __ ldr(rscratch1, Address(rthread, JavaThread::cont_entry_offset()));
 996   __ cmp(sp, rscratch1);
 997   __ br(Assembler::EQ, OK);
 998   __ stop("incorrect sp1");
 999   __ bind(OK);
1000 #endif
1001   __ ldr(rscratch1, Address(sp, ContinuationEntry::parent_cont_fastpath_offset()));
1002   __ str(rscratch1, Address(rthread, JavaThread::cont_fastpath_offset()));
1003   __ ldr(rscratch2, Address(sp, ContinuationEntry::parent_offset()));
1004   __ str(rscratch2, Address(rthread, JavaThread::cont_entry_offset()));
1005   __ add(rfp, sp, (int)ContinuationEntry::size());
1006 }
1007 
1008 // enterSpecial(Continuation c, boolean isContinue, boolean isVirtualThread)
1009 // On entry: c_rarg1 -- the continuation object
1010 //           c_rarg2 -- isContinue
1011 //           c_rarg3 -- isVirtualThread
1012 static void gen_continuation_enter(MacroAssembler* masm,
1013                                  const methodHandle& method,
1014                                  const BasicType* sig_bt,
1015                                  const VMRegPair* regs,
1016                                  int& exception_offset,
1017                                  OopMapSet*oop_maps,
1018                                  int& frame_complete,
1019                                  int& stack_slots,
1020                                  int& interpreted_entry_offset,
1021                                  int& compiled_entry_offset) {
1022   //verify_oop_args(masm, method, sig_bt, regs);
1023   Address resolve(SharedRuntime::get_resolve_static_call_stub(), relocInfo::static_call_type);
1024 
1025   address start = __ pc();
1026 
1027   Label call_thaw, exit;
1028 
1029   // i2i entry used at interp_only_mode only
1030   interpreted_entry_offset = __ pc() - start;
1031   {
1032 
1033 #ifdef ASSERT
1034     Label is_interp_only;
1035     __ ldrw(rscratch1, Address(rthread, JavaThread::interp_only_mode_offset()));
1036     __ cbnzw(rscratch1, is_interp_only);
1037     __ stop("enterSpecial interpreter entry called when not in interp_only_mode");
1038     __ bind(is_interp_only);
1039 #endif
1040 
1041     // Read interpreter arguments into registers (this is an ad-hoc i2c adapter)
1042     __ ldr(c_rarg1, Address(esp, Interpreter::stackElementSize*2));
1043     __ ldr(c_rarg2, Address(esp, Interpreter::stackElementSize*1));
1044     __ ldr(c_rarg3, Address(esp, Interpreter::stackElementSize*0));
1045     __ push_cont_fastpath(rthread);
1046 
1047     __ enter();
1048     stack_slots = 2; // will be adjusted in setup
1049     OopMap* map = continuation_enter_setup(masm, stack_slots);
1050     // The frame is complete here, but we only record it for the compiled entry, so the frame would appear unsafe,
1051     // but that's okay because at the very worst we'll miss an async sample, but we're in interp_only_mode anyway.
1052 
1053     fill_continuation_entry(masm);
1054 
1055     __ cbnz(c_rarg2, call_thaw);
1056 
1057     const address tr_call = __ trampoline_call(resolve);
1058     if (tr_call == nullptr) {
1059       fatal("CodeCache is full at gen_continuation_enter");
1060     }
1061 
1062     oop_maps->add_gc_map(__ pc() - start, map);
1063     __ post_call_nop();
1064 
1065     __ b(exit);
1066 
1067     address stub = CompiledDirectCall::emit_to_interp_stub(masm, tr_call);
1068     if (stub == nullptr) {
1069       fatal("CodeCache is full at gen_continuation_enter");
1070     }
1071   }
1072 
1073   // compiled entry
1074   __ align(CodeEntryAlignment);
1075   compiled_entry_offset = __ pc() - start;
1076 
1077   __ enter();
1078   stack_slots = 2; // will be adjusted in setup
1079   OopMap* map = continuation_enter_setup(masm, stack_slots);
1080   frame_complete = __ pc() - start;
1081 
1082   fill_continuation_entry(masm);
1083 
1084   __ cbnz(c_rarg2, call_thaw);
1085 
1086   const address tr_call = __ trampoline_call(resolve);
1087   if (tr_call == nullptr) {
1088     fatal("CodeCache is full at gen_continuation_enter");
1089   }
1090 
1091   oop_maps->add_gc_map(__ pc() - start, map);
1092   __ post_call_nop();
1093 
1094   __ b(exit);
1095 
1096   __ bind(call_thaw);
1097 
1098   ContinuationEntry::_thaw_call_pc_offset = __ pc() - start;
1099   __ rt_call(CAST_FROM_FN_PTR(address, StubRoutines::cont_thaw()));
1100   oop_maps->add_gc_map(__ pc() - start, map->deep_copy());
1101   ContinuationEntry::_return_pc_offset = __ pc() - start;
1102   __ post_call_nop();
1103 
1104   __ bind(exit);
1105   ContinuationEntry::_cleanup_offset = __ pc() - start;
1106   continuation_enter_cleanup(masm);
1107   __ leave();
1108   __ ret(lr);
1109 
1110   /// exception handling
1111 
1112   exception_offset = __ pc() - start;
1113   {
1114       __ mov(r19, r0); // save return value contaning the exception oop in callee-saved R19
1115 
1116       continuation_enter_cleanup(masm);
1117 
1118       __ ldr(c_rarg1, Address(rfp, wordSize)); // return address
1119       __ authenticate_return_address(c_rarg1);
1120       __ call_VM_leaf(CAST_FROM_FN_PTR(address, SharedRuntime::exception_handler_for_return_address), rthread, c_rarg1);
1121 
1122       // see OptoRuntime::generate_exception_blob: r0 -- exception oop, r3 -- exception pc
1123 
1124       __ mov(r1, r0); // the exception handler
1125       __ mov(r0, r19); // restore return value contaning the exception oop
1126       __ verify_oop(r0);
1127 
1128       __ leave();
1129       __ mov(r3, lr);
1130       __ br(r1); // the exception handler
1131   }
1132 
1133   address stub = CompiledDirectCall::emit_to_interp_stub(masm, tr_call);
1134   if (stub == nullptr) {
1135     fatal("CodeCache is full at gen_continuation_enter");
1136   }
1137 }
1138 
1139 static void gen_continuation_yield(MacroAssembler* masm,
1140                                    const methodHandle& method,
1141                                    const BasicType* sig_bt,
1142                                    const VMRegPair* regs,
1143                                    OopMapSet* oop_maps,
1144                                    int& frame_complete,
1145                                    int& stack_slots,
1146                                    int& compiled_entry_offset) {
1147     enum layout {
1148       rfp_off1,
1149       rfp_off2,
1150       lr_off,
1151       lr_off2,
1152       framesize // inclusive of return address
1153     };
1154     // assert(is_even(framesize/2), "sp not 16-byte aligned");
1155     stack_slots = framesize /  VMRegImpl::slots_per_word;
1156     assert(stack_slots == 2, "recheck layout");
1157 
1158     address start = __ pc();
1159 
1160     compiled_entry_offset = __ pc() - start;
1161     __ enter();
1162 
1163     __ mov(c_rarg1, sp);
1164 
1165     frame_complete = __ pc() - start;
1166     address the_pc = __ pc();
1167 
1168     __ post_call_nop(); // this must be exactly after the pc value that is pushed into the frame info, we use this nop for fast CodeBlob lookup
1169 
1170     __ mov(c_rarg0, rthread);
1171     __ set_last_Java_frame(sp, rfp, the_pc, rscratch1);
1172     __ call_VM_leaf(Continuation::freeze_entry(), 2);
1173     __ reset_last_Java_frame(true);
1174 
1175     Label pinned;
1176 
1177     __ cbnz(r0, pinned);
1178 
1179     // We've succeeded, set sp to the ContinuationEntry
1180     __ ldr(rscratch1, Address(rthread, JavaThread::cont_entry_offset()));
1181     __ mov(sp, rscratch1);
1182     continuation_enter_cleanup(masm);
1183 
1184     __ bind(pinned); // pinned -- return to caller
1185 
1186     // handle pending exception thrown by freeze
1187     __ ldr(rscratch1, Address(rthread, in_bytes(Thread::pending_exception_offset())));
1188     Label ok;
1189     __ cbz(rscratch1, ok);
1190     __ leave();
1191     __ lea(rscratch1, RuntimeAddress(StubRoutines::forward_exception_entry()));
1192     __ br(rscratch1);
1193     __ bind(ok);
1194 
1195     __ leave();
1196     __ ret(lr);
1197 
1198     OopMap* map = new OopMap(framesize, 1);
1199     oop_maps->add_gc_map(the_pc - start, map);
1200 }
1201 
1202 void SharedRuntime::continuation_enter_cleanup(MacroAssembler* masm) {
1203   ::continuation_enter_cleanup(masm);
1204 }
1205 
1206 static void gen_special_dispatch(MacroAssembler* masm,
1207                                  const methodHandle& method,
1208                                  const BasicType* sig_bt,
1209                                  const VMRegPair* regs) {
1210   verify_oop_args(masm, method, sig_bt, regs);
1211   vmIntrinsics::ID iid = method->intrinsic_id();
1212 
1213   // Now write the args into the outgoing interpreter space
1214   bool     has_receiver   = false;
1215   Register receiver_reg   = noreg;
1216   int      member_arg_pos = -1;
1217   Register member_reg     = noreg;
1218   int      ref_kind       = MethodHandles::signature_polymorphic_intrinsic_ref_kind(iid);
1219   if (ref_kind != 0) {
1220     member_arg_pos = method->size_of_parameters() - 1;  // trailing MemberName argument
1221     member_reg = r19;  // known to be free at this point
1222     has_receiver = MethodHandles::ref_kind_has_receiver(ref_kind);
1223   } else if (iid == vmIntrinsics::_invokeBasic) {
1224     has_receiver = true;
1225   } else if (iid == vmIntrinsics::_linkToNative) {
1226     member_arg_pos = method->size_of_parameters() - 1;  // trailing NativeEntryPoint argument
1227     member_reg = r19;  // known to be free at this point
1228   } else {
1229     fatal("unexpected intrinsic id %d", vmIntrinsics::as_int(iid));
1230   }
1231 
1232   if (member_reg != noreg) {
1233     // Load the member_arg into register, if necessary.
1234     SharedRuntime::check_member_name_argument_is_last_argument(method, sig_bt, regs);
1235     VMReg r = regs[member_arg_pos].first();
1236     if (r->is_stack()) {
1237       __ ldr(member_reg, Address(sp, r->reg2stack() * VMRegImpl::stack_slot_size));
1238     } else {
1239       // no data motion is needed
1240       member_reg = r->as_Register();
1241     }
1242   }
1243 
1244   if (has_receiver) {
1245     // Make sure the receiver is loaded into a register.
1246     assert(method->size_of_parameters() > 0, "oob");
1247     assert(sig_bt[0] == T_OBJECT, "receiver argument must be an object");
1248     VMReg r = regs[0].first();
1249     assert(r->is_valid(), "bad receiver arg");
1250     if (r->is_stack()) {
1251       // Porting note:  This assumes that compiled calling conventions always
1252       // pass the receiver oop in a register.  If this is not true on some
1253       // platform, pick a temp and load the receiver from stack.
1254       fatal("receiver always in a register");
1255       receiver_reg = r2;  // known to be free at this point
1256       __ ldr(receiver_reg, Address(sp, r->reg2stack() * VMRegImpl::stack_slot_size));
1257     } else {
1258       // no data motion is needed
1259       receiver_reg = r->as_Register();
1260     }
1261   }
1262 
1263   // Figure out which address we are really jumping to:
1264   MethodHandles::generate_method_handle_dispatch(masm, iid,
1265                                                  receiver_reg, member_reg, /*for_compiler_entry:*/ true);
1266 }
1267 
1268 // ---------------------------------------------------------------------------
1269 // Generate a native wrapper for a given method.  The method takes arguments
1270 // in the Java compiled code convention, marshals them to the native
1271 // convention (handlizes oops, etc), transitions to native, makes the call,
1272 // returns to java state (possibly blocking), unhandlizes any result and
1273 // returns.
1274 //
1275 // Critical native functions are a shorthand for the use of
1276 // GetPrimtiveArrayCritical and disallow the use of any other JNI
1277 // functions.  The wrapper is expected to unpack the arguments before
1278 // passing them to the callee. Critical native functions leave the state _in_Java,
1279 // since they block out GC.
1280 // Some other parts of JNI setup are skipped like the tear down of the JNI handle
1281 // block and the check for pending exceptions it's impossible for them
1282 // to be thrown.
1283 //
1284 nmethod* SharedRuntime::generate_native_wrapper(MacroAssembler* masm,
1285                                                 const methodHandle& method,
1286                                                 int compile_id,
1287                                                 BasicType* in_sig_bt,
1288                                                 VMRegPair* in_regs,
1289                                                 BasicType ret_type) {
1290   if (method->is_continuation_native_intrinsic()) {
1291     int exception_offset = -1;
1292     OopMapSet* oop_maps = new OopMapSet();
1293     int frame_complete = -1;
1294     int stack_slots = -1;
1295     int interpreted_entry_offset = -1;
1296     int vep_offset = -1;
1297     if (method->is_continuation_enter_intrinsic()) {
1298       gen_continuation_enter(masm,
1299                              method,
1300                              in_sig_bt,
1301                              in_regs,
1302                              exception_offset,
1303                              oop_maps,
1304                              frame_complete,
1305                              stack_slots,
1306                              interpreted_entry_offset,
1307                              vep_offset);
1308     } else if (method->is_continuation_yield_intrinsic()) {
1309       gen_continuation_yield(masm,
1310                              method,
1311                              in_sig_bt,
1312                              in_regs,
1313                              oop_maps,
1314                              frame_complete,
1315                              stack_slots,
1316                              vep_offset);
1317     } else {
1318       guarantee(false, "Unknown Continuation native intrinsic");
1319     }
1320 
1321 #ifdef ASSERT
1322     if (method->is_continuation_enter_intrinsic()) {
1323       assert(interpreted_entry_offset != -1, "Must be set");
1324       assert(exception_offset != -1,         "Must be set");
1325     } else {
1326       assert(interpreted_entry_offset == -1, "Must be unset");
1327       assert(exception_offset == -1,         "Must be unset");
1328     }
1329     assert(frame_complete != -1,    "Must be set");
1330     assert(stack_slots != -1,       "Must be set");
1331     assert(vep_offset != -1,        "Must be set");
1332 #endif
1333 
1334     __ flush();
1335     nmethod* nm = nmethod::new_native_nmethod(method,
1336                                               compile_id,
1337                                               masm->code(),
1338                                               vep_offset,
1339                                               frame_complete,
1340                                               stack_slots,
1341                                               in_ByteSize(-1),
1342                                               in_ByteSize(-1),
1343                                               oop_maps,
1344                                               exception_offset);
1345     if (nm == nullptr) return nm;
1346     if (method->is_continuation_enter_intrinsic()) {
1347       ContinuationEntry::set_enter_code(nm, interpreted_entry_offset);
1348     } else if (method->is_continuation_yield_intrinsic()) {
1349       _cont_doYield_stub = nm;
1350     } else {
1351       guarantee(false, "Unknown Continuation native intrinsic");
1352     }
1353     return nm;
1354   }
1355 
1356   if (method->is_method_handle_intrinsic()) {
1357     vmIntrinsics::ID iid = method->intrinsic_id();
1358     intptr_t start = (intptr_t)__ pc();
1359     int vep_offset = ((intptr_t)__ pc()) - start;
1360 
1361     // First instruction must be a nop as it may need to be patched on deoptimisation
1362     __ nop();
1363     gen_special_dispatch(masm,
1364                          method,
1365                          in_sig_bt,
1366                          in_regs);
1367     int frame_complete = ((intptr_t)__ pc()) - start;  // not complete, period
1368     __ flush();
1369     int stack_slots = SharedRuntime::out_preserve_stack_slots();  // no out slots at all, actually
1370     return nmethod::new_native_nmethod(method,
1371                                        compile_id,
1372                                        masm->code(),
1373                                        vep_offset,
1374                                        frame_complete,
1375                                        stack_slots / VMRegImpl::slots_per_word,
1376                                        in_ByteSize(-1),
1377                                        in_ByteSize(-1),
1378                                        nullptr);
1379   }
1380   address native_func = method->native_function();
1381   assert(native_func != nullptr, "must have function");
1382 
1383   // An OopMap for lock (and class if static)
1384   OopMapSet *oop_maps = new OopMapSet();
1385   intptr_t start = (intptr_t)__ pc();
1386 
1387   // We have received a description of where all the java arg are located
1388   // on entry to the wrapper. We need to convert these args to where
1389   // the jni function will expect them. To figure out where they go
1390   // we convert the java signature to a C signature by inserting
1391   // the hidden arguments as arg[0] and possibly arg[1] (static method)
1392 
1393   const int total_in_args = method->size_of_parameters();
1394   int total_c_args = total_in_args + (method->is_static() ? 2 : 1);
1395 
1396   BasicType* out_sig_bt = NEW_RESOURCE_ARRAY(BasicType, total_c_args);
1397   VMRegPair* out_regs   = NEW_RESOURCE_ARRAY(VMRegPair, total_c_args);
1398 
1399   int argc = 0;
1400   out_sig_bt[argc++] = T_ADDRESS;
1401   if (method->is_static()) {
1402     out_sig_bt[argc++] = T_OBJECT;
1403   }
1404 
1405   for (int i = 0; i < total_in_args ; i++ ) {
1406     out_sig_bt[argc++] = in_sig_bt[i];
1407   }
1408 
1409   // Now figure out where the args must be stored and how much stack space
1410   // they require.
1411   int out_arg_slots;
1412   out_arg_slots = c_calling_convention_priv(out_sig_bt, out_regs, total_c_args);
1413 
1414   if (out_arg_slots < 0) {
1415     return nullptr;
1416   }
1417 
1418   // Compute framesize for the wrapper.  We need to handlize all oops in
1419   // incoming registers
1420 
1421   // Calculate the total number of stack slots we will need.
1422 
1423   // First count the abi requirement plus all of the outgoing args
1424   int stack_slots = SharedRuntime::out_preserve_stack_slots() + out_arg_slots;
1425 
1426   // Now the space for the inbound oop handle area
1427   int total_save_slots = 8 * VMRegImpl::slots_per_word;  // 8 arguments passed in registers
1428 
1429   int oop_handle_offset = stack_slots;
1430   stack_slots += total_save_slots;
1431 
1432   // Now any space we need for handlizing a klass if static method
1433 
1434   int klass_slot_offset = 0;
1435   int klass_offset = -1;
1436   int lock_slot_offset = 0;
1437   bool is_static = false;
1438 
1439   if (method->is_static()) {
1440     klass_slot_offset = stack_slots;
1441     stack_slots += VMRegImpl::slots_per_word;
1442     klass_offset = klass_slot_offset * VMRegImpl::stack_slot_size;
1443     is_static = true;
1444   }
1445 
1446   // Plus a lock if needed
1447 
1448   if (method->is_synchronized()) {
1449     lock_slot_offset = stack_slots;
1450     stack_slots += VMRegImpl::slots_per_word;
1451   }
1452 
1453   // Now a place (+2) to save return values or temp during shuffling
1454   // + 4 for return address (which we own) and saved rfp
1455   stack_slots += 6;
1456 
1457   // Ok The space we have allocated will look like:
1458   //
1459   //
1460   // FP-> |                     |
1461   //      |---------------------|
1462   //      | 2 slots for moves   |
1463   //      |---------------------|
1464   //      | lock box (if sync)  |
1465   //      |---------------------| <- lock_slot_offset
1466   //      | klass (if static)   |
1467   //      |---------------------| <- klass_slot_offset
1468   //      | oopHandle area      |
1469   //      |---------------------| <- oop_handle_offset (8 java arg registers)
1470   //      | outbound memory     |
1471   //      | based arguments     |
1472   //      |                     |
1473   //      |---------------------|
1474   //      |                     |
1475   // SP-> | out_preserved_slots |
1476   //
1477   //
1478 
1479 
1480   // Now compute actual number of stack words we need rounding to make
1481   // stack properly aligned.
1482   stack_slots = align_up(stack_slots, StackAlignmentInSlots);
1483 
1484   int stack_size = stack_slots * VMRegImpl::stack_slot_size;
1485 
1486   // First thing make an ic check to see if we should even be here
1487 
1488   // We are free to use all registers as temps without saving them and
1489   // restoring them except rfp. rfp is the only callee save register
1490   // as far as the interpreter and the compiler(s) are concerned.
1491 
1492   const Register receiver = j_rarg0;
1493 
1494   Label exception_pending;
1495 
1496   assert_different_registers(receiver, rscratch1);
1497   __ verify_oop(receiver);
1498   __ ic_check(8 /* end_alignment */);
1499 
1500   // Verified entry point must be aligned
1501   int vep_offset = ((intptr_t)__ pc()) - start;
1502 
1503   // If we have to make this method not-entrant we'll overwrite its
1504   // first instruction with a jump.  For this action to be legal we
1505   // must ensure that this first instruction is a B, BL, NOP, BKPT,
1506   // SVC, HVC, or SMC.  Make it a NOP.
1507   __ nop();
1508 
1509   if (method->needs_clinit_barrier()) {
1510     assert(VM_Version::supports_fast_class_init_checks(), "sanity");
1511     Label L_skip_barrier;
1512     __ mov_metadata(rscratch2, method->method_holder()); // InstanceKlass*
1513     __ clinit_barrier(rscratch2, rscratch1, &L_skip_barrier);
1514     __ far_jump(RuntimeAddress(SharedRuntime::get_handle_wrong_method_stub()));
1515 
1516     __ bind(L_skip_barrier);
1517   }
1518 
1519   // Generate stack overflow check
1520   __ bang_stack_with_offset(checked_cast<int>(StackOverflow::stack_shadow_zone_size()));
1521 
1522   // Generate a new frame for the wrapper.
1523   __ enter();
1524   // -2 because return address is already present and so is saved rfp
1525   __ sub(sp, sp, stack_size - 2*wordSize);
1526 
1527   BarrierSetAssembler* bs = BarrierSet::barrier_set()->barrier_set_assembler();
1528   bs->nmethod_entry_barrier(masm, nullptr /* slow_path */, nullptr /* continuation */, nullptr /* guard */);
1529 
1530   // Frame is now completed as far as size and linkage.
1531   int frame_complete = ((intptr_t)__ pc()) - start;
1532 
1533   // We use r20 as the oop handle for the receiver/klass
1534   // It is callee save so it survives the call to native
1535 
1536   const Register oop_handle_reg = r20;
1537 
1538   //
1539   // We immediately shuffle the arguments so that any vm call we have to
1540   // make from here on out (sync slow path, jvmti, etc.) we will have
1541   // captured the oops from our caller and have a valid oopMap for
1542   // them.
1543 
1544   // -----------------
1545   // The Grand Shuffle
1546 
1547   // The Java calling convention is either equal (linux) or denser (win64) than the
1548   // c calling convention. However the because of the jni_env argument the c calling
1549   // convention always has at least one more (and two for static) arguments than Java.
1550   // Therefore if we move the args from java -> c backwards then we will never have
1551   // a register->register conflict and we don't have to build a dependency graph
1552   // and figure out how to break any cycles.
1553   //
1554 
1555   // Record esp-based slot for receiver on stack for non-static methods
1556   int receiver_offset = -1;
1557 
1558   // This is a trick. We double the stack slots so we can claim
1559   // the oops in the caller's frame. Since we are sure to have
1560   // more args than the caller doubling is enough to make
1561   // sure we can capture all the incoming oop args from the
1562   // caller.
1563   //
1564   OopMap* map = new OopMap(stack_slots * 2, 0 /* arg_slots*/);
1565 
1566   // Mark location of rfp (someday)
1567   // map->set_callee_saved(VMRegImpl::stack2reg( stack_slots - 2), stack_slots * 2, 0, vmreg(rfp));
1568 
1569 
1570   int float_args = 0;
1571   int int_args = 0;
1572 
1573 #ifdef ASSERT
1574   bool reg_destroyed[Register::number_of_registers];
1575   bool freg_destroyed[FloatRegister::number_of_registers];
1576   for ( int r = 0 ; r < Register::number_of_registers ; r++ ) {
1577     reg_destroyed[r] = false;
1578   }
1579   for ( int f = 0 ; f < FloatRegister::number_of_registers ; f++ ) {
1580     freg_destroyed[f] = false;
1581   }
1582 
1583 #endif /* ASSERT */
1584 
1585   // For JNI natives the incoming and outgoing registers are offset upwards.
1586   GrowableArray<int> arg_order(2 * total_in_args);
1587 
1588   for (int i = total_in_args - 1, c_arg = total_c_args - 1; i >= 0; i--, c_arg--) {
1589     arg_order.push(i);
1590     arg_order.push(c_arg);
1591   }
1592 
1593   for (int ai = 0; ai < arg_order.length(); ai += 2) {
1594     int i = arg_order.at(ai);
1595     int c_arg = arg_order.at(ai + 1);
1596     __ block_comment(err_msg("move %d -> %d", i, c_arg));
1597     assert(c_arg != -1 && i != -1, "wrong order");
1598 #ifdef ASSERT
1599     if (in_regs[i].first()->is_Register()) {
1600       assert(!reg_destroyed[in_regs[i].first()->as_Register()->encoding()], "destroyed reg!");
1601     } else if (in_regs[i].first()->is_FloatRegister()) {
1602       assert(!freg_destroyed[in_regs[i].first()->as_FloatRegister()->encoding()], "destroyed reg!");
1603     }
1604     if (out_regs[c_arg].first()->is_Register()) {
1605       reg_destroyed[out_regs[c_arg].first()->as_Register()->encoding()] = true;
1606     } else if (out_regs[c_arg].first()->is_FloatRegister()) {
1607       freg_destroyed[out_regs[c_arg].first()->as_FloatRegister()->encoding()] = true;
1608     }
1609 #endif /* ASSERT */
1610     switch (in_sig_bt[i]) {
1611       case T_ARRAY:
1612       case T_OBJECT:
1613         __ object_move(map, oop_handle_offset, stack_slots, in_regs[i], out_regs[c_arg],
1614                        ((i == 0) && (!is_static)),
1615                        &receiver_offset);
1616         int_args++;
1617         break;
1618       case T_VOID:
1619         break;
1620 
1621       case T_FLOAT:
1622         __ float_move(in_regs[i], out_regs[c_arg]);
1623         float_args++;
1624         break;
1625 
1626       case T_DOUBLE:
1627         assert( i + 1 < total_in_args &&
1628                 in_sig_bt[i + 1] == T_VOID &&
1629                 out_sig_bt[c_arg+1] == T_VOID, "bad arg list");
1630         __ double_move(in_regs[i], out_regs[c_arg]);
1631         float_args++;
1632         break;
1633 
1634       case T_LONG :
1635         __ long_move(in_regs[i], out_regs[c_arg]);
1636         int_args++;
1637         break;
1638 
1639       case T_ADDRESS: assert(false, "found T_ADDRESS in java args");
1640 
1641       default:
1642         __ move32_64(in_regs[i], out_regs[c_arg]);
1643         int_args++;
1644     }
1645   }
1646 
1647   // point c_arg at the first arg that is already loaded in case we
1648   // need to spill before we call out
1649   int c_arg = total_c_args - total_in_args;
1650 
1651   // Pre-load a static method's oop into c_rarg1.
1652   if (method->is_static()) {
1653 
1654     //  load oop into a register
1655     __ movoop(c_rarg1,
1656               JNIHandles::make_local(method->method_holder()->java_mirror()));
1657 
1658     // Now handlize the static class mirror it's known not-null.
1659     __ str(c_rarg1, Address(sp, klass_offset));
1660     map->set_oop(VMRegImpl::stack2reg(klass_slot_offset));
1661 
1662     // Now get the handle
1663     __ lea(c_rarg1, Address(sp, klass_offset));
1664     // and protect the arg if we must spill
1665     c_arg--;
1666   }
1667 
1668   // Change state to native (we save the return address in the thread, since it might not
1669   // be pushed on the stack when we do a stack traversal). It is enough that the pc()
1670   // points into the right code segment. It does not have to be the correct return pc.
1671   // We use the same pc/oopMap repeatedly when we call out.
1672 
1673   Label native_return;
1674   if (method->is_object_wait0()) {
1675     // For convenience we use the pc we want to resume to in case of preemption on Object.wait.
1676     __ set_last_Java_frame(sp, noreg, native_return, rscratch1);
1677   } else {
1678     intptr_t the_pc = (intptr_t) __ pc();
1679     oop_maps->add_gc_map(the_pc - start, map);
1680 
1681     __ set_last_Java_frame(sp, noreg, __ pc(), rscratch1);
1682   }
1683 
1684   Label dtrace_method_entry, dtrace_method_entry_done;
1685   if (DTraceMethodProbes) {
1686     __ b(dtrace_method_entry);
1687     __ bind(dtrace_method_entry_done);
1688   }
1689 
1690   // RedefineClasses() tracing support for obsolete method entry
1691   if (log_is_enabled(Trace, redefine, class, obsolete)) {
1692     // protect the args we've loaded
1693     save_args(masm, total_c_args, c_arg, out_regs);
1694     __ mov_metadata(c_rarg1, method());
1695     __ call_VM_leaf(
1696       CAST_FROM_FN_PTR(address, SharedRuntime::rc_trace_method_entry),
1697       rthread, c_rarg1);
1698     restore_args(masm, total_c_args, c_arg, out_regs);
1699   }
1700 
1701   // Lock a synchronized method
1702 
1703   // Register definitions used by locking and unlocking
1704 
1705   const Register swap_reg = r0;
1706   const Register obj_reg  = r19;  // Will contain the oop
1707   const Register lock_reg = r13;  // Address of compiler lock object (BasicLock)
1708   const Register old_hdr  = r13;  // value of old header at unlock time
1709   const Register lock_tmp = r14;  // Temporary used by fast_lock/unlock
1710   const Register tmp = lr;
1711 
1712   Label slow_path_lock;
1713   Label lock_done;
1714 
1715   if (method->is_synchronized()) {
1716     // Get the handle (the 2nd argument)
1717     __ mov(oop_handle_reg, c_rarg1);
1718 
1719     // Get address of the box
1720 
1721     __ lea(lock_reg, Address(sp, lock_slot_offset * VMRegImpl::stack_slot_size));
1722 
1723     // Load the oop from the handle
1724     __ ldr(obj_reg, Address(oop_handle_reg, 0));
1725 
1726     __ fast_lock(lock_reg, obj_reg, swap_reg, tmp, lock_tmp, slow_path_lock);
1727 
1728     // Slow path will re-enter here
1729     __ bind(lock_done);
1730   }
1731 
1732 
1733   // Finally just about ready to make the JNI call
1734 
1735   // get JNIEnv* which is first argument to native
1736   __ lea(c_rarg0, Address(rthread, in_bytes(JavaThread::jni_environment_offset())));
1737 
1738   // Now set thread in native
1739   __ mov(rscratch1, _thread_in_native);
1740   __ lea(rscratch2, Address(rthread, JavaThread::thread_state_offset()));
1741   __ stlrw(rscratch1, rscratch2);
1742 
1743   __ rt_call(native_func);
1744 
1745   // Verify or restore cpu control state after JNI call
1746   __ restore_cpu_control_state_after_jni(rscratch1, rscratch2);
1747 
1748   // Unpack native results.
1749   switch (ret_type) {
1750   case T_BOOLEAN: __ c2bool(r0);                     break;
1751   case T_CHAR   : __ ubfx(r0, r0, 0, 16);            break;
1752   case T_BYTE   : __ sbfx(r0, r0, 0, 8);             break;
1753   case T_SHORT  : __ sbfx(r0, r0, 0, 16);            break;
1754   case T_INT    : __ sbfx(r0, r0, 0, 32);            break;
1755   case T_DOUBLE :
1756   case T_FLOAT  :
1757     // Result is in v0 we'll save as needed
1758     break;
1759   case T_ARRAY:                 // Really a handle
1760   case T_OBJECT:                // Really a handle
1761       break; // can't de-handlize until after safepoint check
1762   case T_VOID: break;
1763   case T_LONG: break;
1764   default       : ShouldNotReachHere();
1765   }
1766 
1767   Label safepoint_in_progress, safepoint_in_progress_done;
1768 
1769   // Switch thread to "native transition" state before reading the synchronization state.
1770   // This additional state is necessary because reading and testing the synchronization
1771   // state is not atomic w.r.t. GC, as this scenario demonstrates:
1772   //     Java thread A, in _thread_in_native state, loads _not_synchronized and is preempted.
1773   //     VM thread changes sync state to synchronizing and suspends threads for GC.
1774   //     Thread A is resumed to finish this native method, but doesn't block here since it
1775   //     didn't see any synchronization is progress, and escapes.
1776   __ mov(rscratch1, _thread_in_native_trans);
1777 
1778   __ strw(rscratch1, Address(rthread, JavaThread::thread_state_offset()));
1779 
1780   // Force this write out before the read below
1781   if (!UseSystemMemoryBarrier) {
1782     __ dmb(Assembler::ISH);
1783   }
1784 
1785   __ verify_sve_vector_length();
1786 
1787   // Check for safepoint operation in progress and/or pending suspend requests.
1788   {
1789     // No need for acquire as Java threads always disarm themselves.
1790     __ safepoint_poll(safepoint_in_progress, true /* at_return */, false /* in_nmethod */);
1791     __ ldrw(rscratch1, Address(rthread, JavaThread::suspend_flags_offset()));
1792     __ cbnzw(rscratch1, safepoint_in_progress);
1793     __ bind(safepoint_in_progress_done);
1794   }
1795 
1796   // change thread state
1797   __ mov(rscratch1, _thread_in_Java);
1798   __ lea(rscratch2, Address(rthread, JavaThread::thread_state_offset()));
1799   __ stlrw(rscratch1, rscratch2);
1800 
1801   if (method->is_object_wait0()) {
1802     // Check preemption for Object.wait()
1803     __ ldr(rscratch1, Address(rthread, JavaThread::preempt_alternate_return_offset()));
1804     __ cbz(rscratch1, native_return);
1805     __ str(zr, Address(rthread, JavaThread::preempt_alternate_return_offset()));
1806     __ br(rscratch1);
1807     __ bind(native_return);
1808 
1809     intptr_t the_pc = (intptr_t) __ pc();
1810     oop_maps->add_gc_map(the_pc - start, map);
1811   }
1812 
1813   Label reguard;
1814   Label reguard_done;
1815   __ ldrb(rscratch1, Address(rthread, JavaThread::stack_guard_state_offset()));
1816   __ cmpw(rscratch1, StackOverflow::stack_guard_yellow_reserved_disabled);
1817   __ br(Assembler::EQ, reguard);
1818   __ bind(reguard_done);
1819 
1820   // native result if any is live
1821 
1822   // Unlock
1823   Label unlock_done;
1824   Label slow_path_unlock;
1825   if (method->is_synchronized()) {
1826 
1827     // Get locked oop from the handle we passed to jni
1828     __ ldr(obj_reg, Address(oop_handle_reg, 0));
1829 
1830     // Must save r0 if if it is live now because cmpxchg must use it
1831     if (ret_type != T_FLOAT && ret_type != T_DOUBLE && ret_type != T_VOID) {
1832       save_native_result(masm, ret_type, stack_slots);
1833     }
1834 
1835     __ fast_unlock(obj_reg, old_hdr, swap_reg, lock_tmp, slow_path_unlock);
1836 
1837     // slow path re-enters here
1838     __ bind(unlock_done);
1839     if (ret_type != T_FLOAT && ret_type != T_DOUBLE && ret_type != T_VOID) {
1840       restore_native_result(masm, ret_type, stack_slots);
1841     }
1842   }
1843 
1844   Label dtrace_method_exit, dtrace_method_exit_done;
1845   if (DTraceMethodProbes) {
1846     __ b(dtrace_method_exit);
1847     __ bind(dtrace_method_exit_done);
1848   }
1849 
1850   __ reset_last_Java_frame(false);
1851 
1852   // Unbox oop result, e.g. JNIHandles::resolve result.
1853   if (is_reference_type(ret_type)) {
1854     __ resolve_jobject(r0, r1, r2);
1855   }
1856 
1857   if (CheckJNICalls) {
1858     // clear_pending_jni_exception_check
1859     __ str(zr, Address(rthread, JavaThread::pending_jni_exception_check_fn_offset()));
1860   }
1861 
1862   // reset handle block
1863   __ ldr(r2, Address(rthread, JavaThread::active_handles_offset()));
1864   __ str(zr, Address(r2, JNIHandleBlock::top_offset()));
1865 
1866   __ leave();
1867 
1868   #if INCLUDE_JFR
1869   // We need to do a poll test after unwind in case the sampler
1870   // managed to sample the native frame after returning to Java.
1871   Label L_return;
1872   __ ldr(rscratch1, Address(rthread, JavaThread::polling_word_offset()));
1873   address poll_test_pc = __ pc();
1874   __ relocate(relocInfo::poll_return_type);
1875   __ tbz(rscratch1, log2i_exact(SafepointMechanism::poll_bit()), L_return);
1876   assert(SharedRuntime::polling_page_return_handler_blob() != nullptr,
1877     "polling page return stub not created yet");
1878   address stub = SharedRuntime::polling_page_return_handler_blob()->entry_point();
1879   __ adr(rscratch1, InternalAddress(poll_test_pc));
1880   __ str(rscratch1, Address(rthread, JavaThread::saved_exception_pc_offset()));
1881   __ far_jump(RuntimeAddress(stub));
1882   __ bind(L_return);
1883 #endif // INCLUDE_JFR
1884 
1885   // Any exception pending?
1886   __ ldr(rscratch1, Address(rthread, in_bytes(Thread::pending_exception_offset())));
1887   __ cbnz(rscratch1, exception_pending);
1888 
1889   // We're done
1890   __ ret(lr);
1891 
1892   // Unexpected paths are out of line and go here
1893 
1894   // forward the exception
1895   __ bind(exception_pending);
1896 
1897   // and forward the exception
1898   __ far_jump(RuntimeAddress(StubRoutines::forward_exception_entry()));
1899 
1900   // Slow path locking & unlocking
1901   if (method->is_synchronized()) {
1902 
1903     __ block_comment("Slow path lock {");
1904     __ bind(slow_path_lock);
1905 
1906     // has last_Java_frame setup. No exceptions so do vanilla call not call_VM
1907     // args are (oop obj, BasicLock* lock, JavaThread* thread)
1908 
1909     // protect the args we've loaded
1910     save_args(masm, total_c_args, c_arg, out_regs);
1911 
1912     __ mov(c_rarg0, obj_reg);
1913     __ mov(c_rarg1, lock_reg);
1914     __ mov(c_rarg2, rthread);
1915 
1916     // Not a leaf but we have last_Java_frame setup as we want.
1917     // We don't want to unmount in case of contention since that would complicate preserving
1918     // the arguments that had already been marshalled into the native convention. So we force
1919     // the freeze slow path to find this native wrapper frame (see recurse_freeze_native_frame())
1920     // and pin the vthread. Otherwise the fast path won't find it since we don't walk the stack.
1921     __ push_cont_fastpath();
1922     __ call_VM_leaf(CAST_FROM_FN_PTR(address, SharedRuntime::complete_monitor_locking_C), 3);
1923     __ pop_cont_fastpath();
1924     restore_args(masm, total_c_args, c_arg, out_regs);
1925 
1926 #ifdef ASSERT
1927     { Label L;
1928       __ ldr(rscratch1, Address(rthread, in_bytes(Thread::pending_exception_offset())));
1929       __ cbz(rscratch1, L);
1930       __ stop("no pending exception allowed on exit from monitorenter");
1931       __ bind(L);
1932     }
1933 #endif
1934     __ b(lock_done);
1935 
1936     __ block_comment("} Slow path lock");
1937 
1938     __ block_comment("Slow path unlock {");
1939     __ bind(slow_path_unlock);
1940 
1941     // If we haven't already saved the native result we must save it now as xmm registers
1942     // are still exposed.
1943 
1944     if (ret_type == T_FLOAT || ret_type == T_DOUBLE ) {
1945       save_native_result(masm, ret_type, stack_slots);
1946     }
1947 
1948     __ mov(c_rarg2, rthread);
1949     __ lea(c_rarg1, Address(sp, lock_slot_offset * VMRegImpl::stack_slot_size));
1950     __ mov(c_rarg0, obj_reg);
1951 
1952     // Save pending exception around call to VM (which contains an EXCEPTION_MARK)
1953     // NOTE that obj_reg == r19 currently
1954     __ ldr(r19, Address(rthread, in_bytes(Thread::pending_exception_offset())));
1955     __ str(zr, Address(rthread, in_bytes(Thread::pending_exception_offset())));
1956 
1957     __ rt_call(CAST_FROM_FN_PTR(address, SharedRuntime::complete_monitor_unlocking_C));
1958 
1959 #ifdef ASSERT
1960     {
1961       Label L;
1962       __ ldr(rscratch1, Address(rthread, in_bytes(Thread::pending_exception_offset())));
1963       __ cbz(rscratch1, L);
1964       __ stop("no pending exception allowed on exit complete_monitor_unlocking_C");
1965       __ bind(L);
1966     }
1967 #endif /* ASSERT */
1968 
1969     __ str(r19, Address(rthread, in_bytes(Thread::pending_exception_offset())));
1970 
1971     if (ret_type == T_FLOAT || ret_type == T_DOUBLE ) {
1972       restore_native_result(masm, ret_type, stack_slots);
1973     }
1974     __ b(unlock_done);
1975 
1976     __ block_comment("} Slow path unlock");
1977 
1978   } // synchronized
1979 
1980   // SLOW PATH Reguard the stack if needed
1981 
1982   __ bind(reguard);
1983   save_native_result(masm, ret_type, stack_slots);
1984   __ rt_call(CAST_FROM_FN_PTR(address, SharedRuntime::reguard_yellow_pages));
1985   restore_native_result(masm, ret_type, stack_slots);
1986   // and continue
1987   __ b(reguard_done);
1988 
1989   // SLOW PATH safepoint
1990   {
1991     __ block_comment("safepoint {");
1992     __ bind(safepoint_in_progress);
1993 
1994     // Don't use call_VM as it will see a possible pending exception and forward it
1995     // and never return here preventing us from clearing _last_native_pc down below.
1996     //
1997     save_native_result(masm, ret_type, stack_slots);
1998     __ mov(c_rarg0, rthread);
1999 #ifndef PRODUCT
2000   assert(frame::arg_reg_save_area_bytes == 0, "not expecting frame reg save area");
2001 #endif
2002     __ lea(rscratch1, RuntimeAddress(CAST_FROM_FN_PTR(address, JavaThread::check_special_condition_for_native_trans)));
2003     __ blr(rscratch1);
2004 
2005     // Restore any method result value
2006     restore_native_result(masm, ret_type, stack_slots);
2007 
2008     __ b(safepoint_in_progress_done);
2009     __ block_comment("} safepoint");
2010   }
2011 
2012   // SLOW PATH dtrace support
2013   if (DTraceMethodProbes) {
2014     {
2015       __ block_comment("dtrace entry {");
2016       __ bind(dtrace_method_entry);
2017 
2018       // We have all of the arguments setup at this point. We must not touch any register
2019       // argument registers at this point (what if we save/restore them there are no oop?
2020 
2021       save_args(masm, total_c_args, c_arg, out_regs);
2022       __ mov_metadata(c_rarg1, method());
2023       __ call_VM_leaf(
2024         CAST_FROM_FN_PTR(address, SharedRuntime::dtrace_method_entry),
2025         rthread, c_rarg1);
2026       restore_args(masm, total_c_args, c_arg, out_regs);
2027       __ b(dtrace_method_entry_done);
2028       __ block_comment("} dtrace entry");
2029     }
2030 
2031     {
2032       __ block_comment("dtrace exit {");
2033       __ bind(dtrace_method_exit);
2034       save_native_result(masm, ret_type, stack_slots);
2035       __ mov_metadata(c_rarg1, method());
2036       __ call_VM_leaf(
2037         CAST_FROM_FN_PTR(address, SharedRuntime::dtrace_method_exit),
2038         rthread, c_rarg1);
2039       restore_native_result(masm, ret_type, stack_slots);
2040       __ b(dtrace_method_exit_done);
2041       __ block_comment("} dtrace exit");
2042     }
2043   }
2044 
2045   __ flush();
2046 
2047   nmethod *nm = nmethod::new_native_nmethod(method,
2048                                             compile_id,
2049                                             masm->code(),
2050                                             vep_offset,
2051                                             frame_complete,
2052                                             stack_slots / VMRegImpl::slots_per_word,
2053                                             (is_static ? in_ByteSize(klass_offset) : in_ByteSize(receiver_offset)),
2054                                             in_ByteSize(lock_slot_offset*VMRegImpl::stack_slot_size),
2055                                             oop_maps);
2056 
2057   return nm;
2058 }
2059 
2060 // this function returns the adjust size (in number of words) to a c2i adapter
2061 // activation for use during deoptimization
2062 int Deoptimization::last_frame_adjust(int callee_parameters, int callee_locals) {
2063   assert(callee_locals >= callee_parameters,
2064           "test and remove; got more parms than locals");
2065   if (callee_locals < callee_parameters)
2066     return 0;                   // No adjustment for negative locals
2067   int diff = (callee_locals - callee_parameters) * Interpreter::stackElementWords;
2068   // diff is counted in stack words
2069   return align_up(diff, 2);
2070 }
2071 
2072 
2073 //------------------------------generate_deopt_blob----------------------------
2074 void SharedRuntime::generate_deopt_blob() {
2075   // Allocate space for the code
2076   ResourceMark rm;
2077   // Setup code generation tools
2078   int pad = 0;
2079 #if INCLUDE_JVMCI
2080   if (EnableJVMCI) {
2081     pad += 512; // Increase the buffer size when compiling for JVMCI
2082   }
2083 #endif
2084   const char* name = SharedRuntime::stub_name(StubId::shared_deopt_id);
2085   CodeBlob* blob = AOTCodeCache::load_code_blob(AOTCodeEntry::SharedBlob, BlobId::shared_deopt_id);
2086   if (blob != nullptr) {
2087     _deopt_blob = blob->as_deoptimization_blob();
2088     return;
2089   }
2090 
2091   CodeBuffer buffer(name, 2048+pad, 1024);
2092   MacroAssembler* masm = new MacroAssembler(&buffer);
2093   int frame_size_in_words;
2094   OopMap* map = nullptr;
2095   OopMapSet *oop_maps = new OopMapSet();
2096   RegisterSaver reg_save(COMPILER2_OR_JVMCI != 0);
2097 
2098   // -------------
2099   // This code enters when returning to a de-optimized nmethod.  A return
2100   // address has been pushed on the stack, and return values are in
2101   // registers.
2102   // If we are doing a normal deopt then we were called from the patched
2103   // nmethod from the point we returned to the nmethod. So the return
2104   // address on the stack is wrong by NativeCall::instruction_size
2105   // We will adjust the value so it looks like we have the original return
2106   // address on the stack (like when we eagerly deoptimized).
2107   // In the case of an exception pending when deoptimizing, we enter
2108   // with a return address on the stack that points after the call we patched
2109   // into the exception handler. We have the following register state from,
2110   // e.g., the forward exception stub (see stubGenerator_x86_64.cpp).
2111   //    r0: exception oop
2112   //    r19: exception handler
2113   //    r3: throwing pc
2114   // So in this case we simply jam r3 into the useless return address and
2115   // the stack looks just like we want.
2116   //
2117   // At this point we need to de-opt.  We save the argument return
2118   // registers.  We call the first C routine, fetch_unroll_info().  This
2119   // routine captures the return values and returns a structure which
2120   // describes the current frame size and the sizes of all replacement frames.
2121   // The current frame is compiled code and may contain many inlined
2122   // functions, each with their own JVM state.  We pop the current frame, then
2123   // push all the new frames.  Then we call the C routine unpack_frames() to
2124   // populate these frames.  Finally unpack_frames() returns us the new target
2125   // address.  Notice that callee-save registers are BLOWN here; they have
2126   // already been captured in the vframeArray at the time the return PC was
2127   // patched.
2128   address start = __ pc();
2129   Label cont;
2130 
2131   // Prolog for non exception case!
2132 
2133   // Save everything in sight.
2134   map = reg_save.save_live_registers(masm, 0, &frame_size_in_words);
2135 
2136   // Normal deoptimization.  Save exec mode for unpack_frames.
2137   __ movw(rcpool, Deoptimization::Unpack_deopt); // callee-saved
2138   __ b(cont);
2139 
2140   int reexecute_offset = __ pc() - start;
2141 #if INCLUDE_JVMCI && !defined(COMPILER1)
2142   if (UseJVMCICompiler) {
2143     // JVMCI does not use this kind of deoptimization
2144     __ should_not_reach_here();
2145   }
2146 #endif
2147 
2148   // Reexecute case
2149   // return address is the pc describes what bci to do re-execute at
2150 
2151   // No need to update map as each call to save_live_registers will produce identical oopmap
2152   (void) reg_save.save_live_registers(masm, 0, &frame_size_in_words);
2153 
2154   __ movw(rcpool, Deoptimization::Unpack_reexecute); // callee-saved
2155   __ b(cont);
2156 
2157 #if INCLUDE_JVMCI
2158   Label after_fetch_unroll_info_call;
2159   int implicit_exception_uncommon_trap_offset = 0;
2160   int uncommon_trap_offset = 0;
2161 
2162   if (EnableJVMCI) {
2163     implicit_exception_uncommon_trap_offset = __ pc() - start;
2164 
2165     __ ldr(lr, Address(rthread, in_bytes(JavaThread::jvmci_implicit_exception_pc_offset())));
2166     __ str(zr, Address(rthread, in_bytes(JavaThread::jvmci_implicit_exception_pc_offset())));
2167 
2168     uncommon_trap_offset = __ pc() - start;
2169 
2170     // Save everything in sight.
2171     reg_save.save_live_registers(masm, 0, &frame_size_in_words);
2172     // fetch_unroll_info needs to call last_java_frame()
2173     Label retaddr;
2174     __ set_last_Java_frame(sp, noreg, retaddr, rscratch1);
2175 
2176     __ ldrw(c_rarg1, Address(rthread, in_bytes(JavaThread::pending_deoptimization_offset())));
2177     __ movw(rscratch1, -1);
2178     __ strw(rscratch1, Address(rthread, in_bytes(JavaThread::pending_deoptimization_offset())));
2179 
2180     __ movw(rcpool, (int32_t)Deoptimization::Unpack_reexecute);
2181     __ mov(c_rarg0, rthread);
2182     __ movw(c_rarg2, rcpool); // exec mode
2183     __ lea(rscratch1,
2184            RuntimeAddress(CAST_FROM_FN_PTR(address,
2185                                            Deoptimization::uncommon_trap)));
2186     __ blr(rscratch1);
2187     __ bind(retaddr);
2188     oop_maps->add_gc_map( __ pc()-start, map->deep_copy());
2189 
2190     __ reset_last_Java_frame(false);
2191 
2192     __ b(after_fetch_unroll_info_call);
2193   } // EnableJVMCI
2194 #endif // INCLUDE_JVMCI
2195 
2196   int exception_offset = __ pc() - start;
2197 
2198   // Prolog for exception case
2199 
2200   // all registers are dead at this entry point, except for r0, and
2201   // r3 which contain the exception oop and exception pc
2202   // respectively.  Set them in TLS and fall thru to the
2203   // unpack_with_exception_in_tls entry point.
2204 
2205   __ str(r3, Address(rthread, JavaThread::exception_pc_offset()));
2206   __ str(r0, Address(rthread, JavaThread::exception_oop_offset()));
2207 
2208   int exception_in_tls_offset = __ pc() - start;
2209 
2210   // new implementation because exception oop is now passed in JavaThread
2211 
2212   // Prolog for exception case
2213   // All registers must be preserved because they might be used by LinearScan
2214   // Exceptiop oop and throwing PC are passed in JavaThread
2215   // tos: stack at point of call to method that threw the exception (i.e. only
2216   // args are on the stack, no return address)
2217 
2218   // The return address pushed by save_live_registers will be patched
2219   // later with the throwing pc. The correct value is not available
2220   // now because loading it from memory would destroy registers.
2221 
2222   // NB: The SP at this point must be the SP of the method that is
2223   // being deoptimized.  Deoptimization assumes that the frame created
2224   // here by save_live_registers is immediately below the method's SP.
2225   // This is a somewhat fragile mechanism.
2226 
2227   // Save everything in sight.
2228   map = reg_save.save_live_registers(masm, 0, &frame_size_in_words);
2229 
2230   // Now it is safe to overwrite any register
2231 
2232   // Deopt during an exception.  Save exec mode for unpack_frames.
2233   __ mov(rcpool, Deoptimization::Unpack_exception); // callee-saved
2234 
2235   // load throwing pc from JavaThread and patch it as the return address
2236   // of the current frame. Then clear the field in JavaThread
2237   __ ldr(r3, Address(rthread, JavaThread::exception_pc_offset()));
2238   __ protect_return_address(r3);
2239   __ str(r3, Address(rfp, wordSize));
2240   __ str(zr, Address(rthread, JavaThread::exception_pc_offset()));
2241 
2242 #ifdef ASSERT
2243   // verify that there is really an exception oop in JavaThread
2244   __ ldr(r0, Address(rthread, JavaThread::exception_oop_offset()));
2245   __ verify_oop(r0);
2246 
2247   // verify that there is no pending exception
2248   Label no_pending_exception;
2249   __ ldr(rscratch1, Address(rthread, Thread::pending_exception_offset()));
2250   __ cbz(rscratch1, no_pending_exception);
2251   __ stop("must not have pending exception here");
2252   __ bind(no_pending_exception);
2253 #endif
2254 
2255   __ bind(cont);
2256 
2257   // Call C code.  Need thread and this frame, but NOT official VM entry
2258   // crud.  We cannot block on this call, no GC can happen.
2259   //
2260   // UnrollBlock* fetch_unroll_info(JavaThread* thread)
2261 
2262   // fetch_unroll_info needs to call last_java_frame().
2263 
2264   Label retaddr;
2265   __ set_last_Java_frame(sp, noreg, retaddr, rscratch1);
2266 #ifdef ASSERT
2267   { Label L;
2268     __ ldr(rscratch1, Address(rthread, JavaThread::last_Java_fp_offset()));
2269     __ cbz(rscratch1, L);
2270     __ stop("SharedRuntime::generate_deopt_blob: last_Java_fp not cleared");
2271     __ bind(L);
2272   }
2273 #endif // ASSERT
2274   __ mov(c_rarg0, rthread);
2275   __ mov(c_rarg1, rcpool);
2276   __ lea(rscratch1, RuntimeAddress(CAST_FROM_FN_PTR(address, Deoptimization::fetch_unroll_info)));
2277   __ blr(rscratch1);
2278   __ bind(retaddr);
2279 
2280   // Need to have an oopmap that tells fetch_unroll_info where to
2281   // find any register it might need.
2282   oop_maps->add_gc_map(__ pc() - start, map);
2283 
2284   __ reset_last_Java_frame(false);
2285 
2286 #if INCLUDE_JVMCI
2287   if (EnableJVMCI) {
2288     __ bind(after_fetch_unroll_info_call);
2289   }
2290 #endif
2291 
2292   // Load UnrollBlock* into r5
2293   __ mov(r5, r0);
2294 
2295   __ ldrw(rcpool, Address(r5, Deoptimization::UnrollBlock::unpack_kind_offset()));
2296    Label noException;
2297   __ cmpw(rcpool, Deoptimization::Unpack_exception);   // Was exception pending?
2298   __ br(Assembler::NE, noException);
2299   __ ldr(r0, Address(rthread, JavaThread::exception_oop_offset()));
2300   // QQQ this is useless it was null above
2301   __ ldr(r3, Address(rthread, JavaThread::exception_pc_offset()));
2302   __ str(zr, Address(rthread, JavaThread::exception_oop_offset()));
2303   __ str(zr, Address(rthread, JavaThread::exception_pc_offset()));
2304 
2305   __ verify_oop(r0);
2306 
2307   // Overwrite the result registers with the exception results.
2308   __ str(r0, Address(sp, reg_save.r0_offset_in_bytes()));
2309   // I think this is useless
2310   // __ str(r3, Address(sp, RegisterSaver::r3_offset_in_bytes()));
2311 
2312   __ bind(noException);
2313 
2314   // Only register save data is on the stack.
2315   // Now restore the result registers.  Everything else is either dead
2316   // or captured in the vframeArray.
2317 
2318   // Restore fp result register
2319   __ ldrd(v0, Address(sp, reg_save.v0_offset_in_bytes()));
2320   // Restore integer result register
2321   __ ldr(r0, Address(sp, reg_save.r0_offset_in_bytes()));
2322 
2323   // Pop all of the register save area off the stack
2324   __ add(sp, sp, frame_size_in_words * wordSize);
2325 
2326   // All of the register save area has been popped of the stack. Only the
2327   // return address remains.
2328 
2329   // Pop all the frames we must move/replace.
2330   //
2331   // Frame picture (youngest to oldest)
2332   // 1: self-frame (no frame link)
2333   // 2: deopting frame  (no frame link)
2334   // 3: caller of deopting frame (could be compiled/interpreted).
2335   //
2336   // Note: by leaving the return address of self-frame on the stack
2337   // and using the size of frame 2 to adjust the stack
2338   // when we are done the return to frame 3 will still be on the stack.
2339 
2340   // Pop deoptimized frame
2341   __ ldrw(r2, Address(r5, Deoptimization::UnrollBlock::size_of_deoptimized_frame_offset()));
2342   __ sub(r2, r2, 2 * wordSize);
2343   __ add(sp, sp, r2);
2344   __ ldp(rfp, zr, __ post(sp, 2 * wordSize));
2345 
2346 #ifdef ASSERT
2347   // Compilers generate code that bang the stack by as much as the
2348   // interpreter would need. So this stack banging should never
2349   // trigger a fault. Verify that it does not on non product builds.
2350   __ ldrw(r19, Address(r5, Deoptimization::UnrollBlock::total_frame_sizes_offset()));
2351   __ bang_stack_size(r19, r2);
2352 #endif
2353   // Load address of array of frame pcs into r2
2354   __ ldr(r2, Address(r5, Deoptimization::UnrollBlock::frame_pcs_offset()));
2355 
2356   // Trash the old pc
2357   // __ addptr(sp, wordSize);  FIXME ????
2358 
2359   // Load address of array of frame sizes into r4
2360   __ ldr(r4, Address(r5, Deoptimization::UnrollBlock::frame_sizes_offset()));
2361 
2362   // Load counter into r3
2363   __ ldrw(r3, Address(r5, Deoptimization::UnrollBlock::number_of_frames_offset()));
2364 
2365   // Now adjust the caller's stack to make up for the extra locals
2366   // but record the original sp so that we can save it in the skeletal interpreter
2367   // frame and the stack walking of interpreter_sender will get the unextended sp
2368   // value and not the "real" sp value.
2369 
2370   const Register sender_sp = r6;
2371 
2372   __ mov(sender_sp, sp);
2373   __ ldrw(r19, Address(r5,
2374                        Deoptimization::UnrollBlock::
2375                        caller_adjustment_offset()));
2376   __ sub(sp, sp, r19);
2377 
2378   // Push interpreter frames in a loop
2379   __ mov(rscratch1, (uint64_t)0xDEADDEAD);        // Make a recognizable pattern
2380   __ mov(rscratch2, rscratch1);
2381   Label loop;
2382   __ bind(loop);
2383   __ ldr(r19, Address(__ post(r4, wordSize)));          // Load frame size
2384   __ sub(r19, r19, 2*wordSize);           // We'll push pc and fp by hand
2385   __ ldr(lr, Address(__ post(r2, wordSize)));  // Load pc
2386   __ enter();                           // Save old & set new fp
2387   __ sub(sp, sp, r19);                  // Prolog
2388   // This value is corrected by layout_activation_impl
2389   __ str(zr, Address(rfp, frame::interpreter_frame_last_sp_offset * wordSize));
2390   __ str(sender_sp, Address(rfp, frame::interpreter_frame_sender_sp_offset * wordSize)); // Make it walkable
2391   __ mov(sender_sp, sp);               // Pass sender_sp to next frame
2392   __ sub(r3, r3, 1);                   // Decrement counter
2393   __ cbnz(r3, loop);
2394 
2395     // Re-push self-frame
2396   __ ldr(lr, Address(r2));
2397   __ enter();
2398 
2399   // Allocate a full sized register save area.  We subtract 2 because
2400   // enter() just pushed 2 words
2401   __ sub(sp, sp, (frame_size_in_words - 2) * wordSize);
2402 
2403   // Restore frame locals after moving the frame
2404   __ strd(v0, Address(sp, reg_save.v0_offset_in_bytes()));
2405   __ str(r0, Address(sp, reg_save.r0_offset_in_bytes()));
2406 
2407   // Call C code.  Need thread but NOT official VM entry
2408   // crud.  We cannot block on this call, no GC can happen.  Call should
2409   // restore return values to their stack-slots with the new SP.
2410   //
2411   // void Deoptimization::unpack_frames(JavaThread* thread, int exec_mode)
2412 
2413   // Use rfp because the frames look interpreted now
2414   // Don't need the precise return PC here, just precise enough to point into this code blob.
2415   address the_pc = __ pc();
2416   __ set_last_Java_frame(sp, rfp, the_pc, rscratch1);
2417 
2418   __ mov(c_rarg0, rthread);
2419   __ movw(c_rarg1, rcpool); // second arg: exec_mode
2420   __ lea(rscratch1, RuntimeAddress(CAST_FROM_FN_PTR(address, Deoptimization::unpack_frames)));
2421   __ blr(rscratch1);
2422 
2423   // Set an oopmap for the call site
2424   // Use the same PC we used for the last java frame
2425   oop_maps->add_gc_map(the_pc - start,
2426                        new OopMap( frame_size_in_words, 0 ));
2427 
2428   // Clear fp AND pc
2429   __ reset_last_Java_frame(true);
2430 
2431   // Collect return values
2432   __ ldrd(v0, Address(sp, reg_save.v0_offset_in_bytes()));
2433   __ ldr(r0, Address(sp, reg_save.r0_offset_in_bytes()));
2434   // I think this is useless (throwing pc?)
2435   // __ ldr(r3, Address(sp, RegisterSaver::r3_offset_in_bytes()));
2436 
2437   // Pop self-frame.
2438   __ leave();                           // Epilog
2439 
2440   // Jump to interpreter
2441   __ ret(lr);
2442 
2443   // Make sure all code is generated
2444   masm->flush();
2445 
2446   _deopt_blob = DeoptimizationBlob::create(&buffer, oop_maps, 0, exception_offset, reexecute_offset, frame_size_in_words);
2447   _deopt_blob->set_unpack_with_exception_in_tls_offset(exception_in_tls_offset);
2448 #if INCLUDE_JVMCI
2449   if (EnableJVMCI) {
2450     _deopt_blob->set_uncommon_trap_offset(uncommon_trap_offset);
2451     _deopt_blob->set_implicit_exception_uncommon_trap_offset(implicit_exception_uncommon_trap_offset);
2452   }
2453 #endif
2454 
2455   AOTCodeCache::store_code_blob(*_deopt_blob, AOTCodeEntry::SharedBlob, BlobId::shared_deopt_id);
2456 }
2457 
2458 // Number of stack slots between incoming argument block and the start of
2459 // a new frame.  The PROLOG must add this many slots to the stack.  The
2460 // EPILOG must remove this many slots. aarch64 needs two slots for
2461 // return address and fp.
2462 // TODO think this is correct but check
2463 uint SharedRuntime::in_preserve_stack_slots() {
2464   return 4;
2465 }
2466 
2467 uint SharedRuntime::out_preserve_stack_slots() {
2468   return 0;
2469 }
2470 
2471 
2472 VMReg SharedRuntime::thread_register() {
2473   return rthread->as_VMReg();
2474 }
2475 
2476 //------------------------------generate_handler_blob------
2477 //
2478 // Generate a special Compile2Runtime blob that saves all registers,
2479 // and setup oopmap.
2480 //
2481 SafepointBlob* SharedRuntime::generate_handler_blob(StubId id, address call_ptr) {
2482   assert(is_polling_page_id(id), "expected a polling page stub id");
2483 
2484   // Allocate space for the code.  Setup code generation tools.
2485   const char* name = SharedRuntime::stub_name(id);
2486   CodeBlob* blob = AOTCodeCache::load_code_blob(AOTCodeEntry::SharedBlob, StubInfo::blob(id));
2487   if (blob != nullptr) {
2488     return blob->as_safepoint_blob();
2489   }
2490 
2491   ResourceMark rm;
2492   OopMapSet *oop_maps = new OopMapSet();
2493   OopMap* map;
2494   CodeBuffer buffer(name, 2048, 1024);
2495   MacroAssembler* masm = new MacroAssembler(&buffer);
2496 
2497   address start   = __ pc();
2498   address call_pc = nullptr;
2499   int frame_size_in_words;
2500   bool cause_return = (id == StubId::shared_polling_page_return_handler_id);
2501   RegisterSaver reg_save(id == StubId::shared_polling_page_vectors_safepoint_handler_id /* save_vectors */);
2502 
2503   // When the signal occurred, the LR was either signed and stored on the stack (in which
2504   // case it will be restored from the stack before being used) or unsigned and not stored
2505   // on the stack. Stipping ensures we get the right value.
2506   __ strip_return_address();
2507 
2508   // Save Integer and Float registers.
2509   map = reg_save.save_live_registers(masm, 0, &frame_size_in_words);
2510 
2511   // The following is basically a call_VM.  However, we need the precise
2512   // address of the call in order to generate an oopmap. Hence, we do all the
2513   // work ourselves.
2514 
2515   Label retaddr;
2516   __ set_last_Java_frame(sp, noreg, retaddr, rscratch1);
2517 
2518   // The return address must always be correct so that frame constructor never
2519   // sees an invalid pc.
2520 
2521   if (!cause_return) {
2522     // overwrite the return address pushed by save_live_registers
2523     // Additionally, r20 is a callee-saved register so we can look at
2524     // it later to determine if someone changed the return address for
2525     // us!
2526     __ ldr(r20, Address(rthread, JavaThread::saved_exception_pc_offset()));
2527     __ protect_return_address(r20);
2528     __ str(r20, Address(rfp, wordSize));
2529   }
2530 
2531   // Do the call
2532   __ mov(c_rarg0, rthread);
2533   __ lea(rscratch1, RuntimeAddress(call_ptr));
2534   __ blr(rscratch1);
2535   __ bind(retaddr);
2536 
2537   // Set an oopmap for the call site.  This oopmap will map all
2538   // oop-registers and debug-info registers as callee-saved.  This
2539   // will allow deoptimization at this safepoint to find all possible
2540   // debug-info recordings, as well as let GC find all oops.
2541 
2542   oop_maps->add_gc_map( __ pc() - start, map);
2543 
2544   Label noException;
2545 
2546   __ reset_last_Java_frame(false);
2547 
2548   __ membar(Assembler::LoadLoad | Assembler::LoadStore);
2549 
2550   __ ldr(rscratch1, Address(rthread, Thread::pending_exception_offset()));
2551   __ cbz(rscratch1, noException);
2552 
2553   // Exception pending
2554 
2555   reg_save.restore_live_registers(masm);
2556 
2557   __ far_jump(RuntimeAddress(StubRoutines::forward_exception_entry()));
2558 
2559   // No exception case
2560   __ bind(noException);
2561 
2562   Label no_adjust, bail;
2563   if (!cause_return) {
2564     // If our stashed return pc was modified by the runtime we avoid touching it
2565     __ ldr(rscratch1, Address(rfp, wordSize));
2566     __ cmp(r20, rscratch1);
2567     __ br(Assembler::NE, no_adjust);
2568     __ authenticate_return_address(r20);
2569 
2570 #ifdef ASSERT
2571     // Verify the correct encoding of the poll we're about to skip.
2572     // See NativeInstruction::is_ldrw_to_zr()
2573     __ ldrw(rscratch1, Address(r20));
2574     __ ubfx(rscratch2, rscratch1, 22, 10);
2575     __ cmpw(rscratch2, 0b1011100101);
2576     __ br(Assembler::NE, bail);
2577     __ ubfx(rscratch2, rscratch1, 0, 5);
2578     __ cmpw(rscratch2, 0b11111);
2579     __ br(Assembler::NE, bail);
2580 #endif
2581     // Adjust return pc forward to step over the safepoint poll instruction
2582     __ add(r20, r20, NativeInstruction::instruction_size);
2583     __ protect_return_address(r20);
2584     __ str(r20, Address(rfp, wordSize));
2585   }
2586 
2587   __ bind(no_adjust);
2588   // Normal exit, restore registers and exit.
2589   reg_save.restore_live_registers(masm);
2590 
2591   __ ret(lr);
2592 
2593 #ifdef ASSERT
2594   __ bind(bail);
2595   __ stop("Attempting to adjust pc to skip safepoint poll but the return point is not what we expected");
2596 #endif
2597 
2598   // Make sure all code is generated
2599   masm->flush();
2600 
2601   // Fill-out other meta info
2602   SafepointBlob* sp_blob = SafepointBlob::create(&buffer, oop_maps, frame_size_in_words);
2603 
2604   AOTCodeCache::store_code_blob(*sp_blob, AOTCodeEntry::SharedBlob, StubInfo::blob(id));
2605   return sp_blob;
2606 }
2607 
2608 //
2609 // generate_resolve_blob - call resolution (static/virtual/opt-virtual/ic-miss
2610 //
2611 // Generate a stub that calls into vm to find out the proper destination
2612 // of a java call. All the argument registers are live at this point
2613 // but since this is generic code we don't know what they are and the caller
2614 // must do any gc of the args.
2615 //
2616 RuntimeStub* SharedRuntime::generate_resolve_blob(StubId id, address destination) {
2617   assert (StubRoutines::forward_exception_entry() != nullptr, "must be generated before");
2618   assert(is_resolve_id(id), "expected a resolve stub id");
2619 
2620   const char* name = SharedRuntime::stub_name(id);
2621   CodeBlob* blob = AOTCodeCache::load_code_blob(AOTCodeEntry::SharedBlob, StubInfo::blob(id));
2622   if (blob != nullptr) {
2623     return blob->as_runtime_stub();
2624   }
2625 
2626   // allocate space for the code
2627   ResourceMark rm;
2628   CodeBuffer buffer(name, 1000, 512);
2629   MacroAssembler* masm                = new MacroAssembler(&buffer);
2630 
2631   int frame_size_in_words;
2632   RegisterSaver reg_save(false /* save_vectors */);
2633 
2634   OopMapSet *oop_maps = new OopMapSet();
2635   OopMap* map = nullptr;
2636 
2637   int start = __ offset();
2638 
2639   map = reg_save.save_live_registers(masm, 0, &frame_size_in_words);
2640 
2641   int frame_complete = __ offset();
2642 
2643   {
2644     Label retaddr;
2645     __ set_last_Java_frame(sp, noreg, retaddr, rscratch1);
2646 
2647     __ mov(c_rarg0, rthread);
2648     __ lea(rscratch1, RuntimeAddress(destination));
2649 
2650     __ blr(rscratch1);
2651     __ bind(retaddr);
2652   }
2653 
2654   // Set an oopmap for the call site.
2655   // We need this not only for callee-saved registers, but also for volatile
2656   // registers that the compiler might be keeping live across a safepoint.
2657 
2658   oop_maps->add_gc_map( __ offset() - start, map);
2659 
2660   // r0 contains the address we are going to jump to assuming no exception got installed
2661 
2662   // clear last_Java_sp
2663   __ reset_last_Java_frame(false);
2664   // check for pending exceptions
2665   Label pending;
2666   __ ldr(rscratch1, Address(rthread, Thread::pending_exception_offset()));
2667   __ cbnz(rscratch1, pending);
2668 
2669   // get the returned Method*
2670   __ get_vm_result_metadata(rmethod, rthread);
2671   __ str(rmethod, Address(sp, reg_save.reg_offset_in_bytes(rmethod)));
2672 
2673   // r0 is where we want to jump, overwrite rscratch1 which is saved and scratch
2674   __ str(r0, Address(sp, reg_save.rscratch1_offset_in_bytes()));
2675   reg_save.restore_live_registers(masm);
2676 
2677   // We are back to the original state on entry and ready to go.
2678 
2679   __ br(rscratch1);
2680 
2681   // Pending exception after the safepoint
2682 
2683   __ bind(pending);
2684 
2685   reg_save.restore_live_registers(masm);
2686 
2687   // exception pending => remove activation and forward to exception handler
2688 
2689   __ str(zr, Address(rthread, JavaThread::vm_result_oop_offset()));
2690 
2691   __ ldr(r0, Address(rthread, Thread::pending_exception_offset()));
2692   __ far_jump(RuntimeAddress(StubRoutines::forward_exception_entry()));
2693 
2694   // -------------
2695   // make sure all code is generated
2696   masm->flush();
2697 
2698   // return the  blob
2699   // frame_size_words or bytes??
2700   RuntimeStub* rs_blob = RuntimeStub::new_runtime_stub(name, &buffer, frame_complete, frame_size_in_words, oop_maps, true);
2701 
2702   AOTCodeCache::store_code_blob(*rs_blob, AOTCodeEntry::SharedBlob, StubInfo::blob(id));
2703   return rs_blob;
2704 }
2705 
2706 // Continuation point for throwing of implicit exceptions that are
2707 // not handled in the current activation. Fabricates an exception
2708 // oop and initiates normal exception dispatching in this
2709 // frame. Since we need to preserve callee-saved values (currently
2710 // only for C2, but done for C1 as well) we need a callee-saved oop
2711 // map and therefore have to make these stubs into RuntimeStubs
2712 // rather than BufferBlobs.  If the compiler needs all registers to
2713 // be preserved between the fault point and the exception handler
2714 // then it must assume responsibility for that in
2715 // AbstractCompiler::continuation_for_implicit_null_exception or
2716 // continuation_for_implicit_division_by_zero_exception. All other
2717 // implicit exceptions (e.g., NullPointerException or
2718 // AbstractMethodError on entry) are either at call sites or
2719 // otherwise assume that stack unwinding will be initiated, so
2720 // caller saved registers were assumed volatile in the compiler.
2721 
2722 RuntimeStub* SharedRuntime::generate_throw_exception(StubId id, address runtime_entry) {
2723   assert(is_throw_id(id), "expected a throw stub id");
2724 
2725   const char* name = SharedRuntime::stub_name(id);
2726 
2727   // Information about frame layout at time of blocking runtime call.
2728   // Note that we only have to preserve callee-saved registers since
2729   // the compilers are responsible for supplying a continuation point
2730   // if they expect all registers to be preserved.
2731   // n.b. aarch64 asserts that frame::arg_reg_save_area_bytes == 0
2732   enum layout {
2733     rfp_off = 0,
2734     rfp_off2,
2735     return_off,
2736     return_off2,
2737     framesize // inclusive of return address
2738   };
2739 
2740   int insts_size = 512;
2741   int locs_size  = 64;
2742 
2743   const char* timer_msg = "SharedRuntime generate_throw_exception";
2744   TraceTime timer(timer_msg, TRACETIME_LOG(Info, startuptime));
2745 
2746   CodeBlob* blob = AOTCodeCache::load_code_blob(AOTCodeEntry::SharedBlob, StubInfo::blob(id));
2747   if (blob != nullptr) {
2748     return blob->as_runtime_stub();
2749   }
2750 
2751   ResourceMark rm;
2752   CodeBuffer code(name, insts_size, locs_size);
2753   OopMapSet* oop_maps  = new OopMapSet();
2754   MacroAssembler* masm = new MacroAssembler(&code);
2755 
2756   address start = __ pc();
2757 
2758   // This is an inlined and slightly modified version of call_VM
2759   // which has the ability to fetch the return PC out of
2760   // thread-local storage and also sets up last_Java_sp slightly
2761   // differently than the real call_VM
2762 
2763   __ enter(); // Save FP and LR before call
2764 
2765   assert(is_even(framesize/2), "sp not 16-byte aligned");
2766 
2767   // lr and fp are already in place
2768   __ sub(sp, rfp, ((uint64_t)framesize-4) << LogBytesPerInt); // prolog
2769 
2770   int frame_complete = __ pc() - start;
2771 
2772   // Set up last_Java_sp and last_Java_fp
2773   address the_pc = __ pc();
2774   __ set_last_Java_frame(sp, rfp, the_pc, rscratch1);
2775 
2776   __ mov(c_rarg0, rthread);
2777   BLOCK_COMMENT("call runtime_entry");
2778   __ lea(rscratch1, RuntimeAddress(runtime_entry));
2779   __ blr(rscratch1);
2780 
2781   // Generate oop map
2782   OopMap* map = new OopMap(framesize, 0);
2783 
2784   oop_maps->add_gc_map(the_pc - start, map);
2785 
2786   __ reset_last_Java_frame(true);
2787 
2788   // Reinitialize the ptrue predicate register, in case the external runtime
2789   // call clobbers ptrue reg, as we may return to SVE compiled code.
2790   __ reinitialize_ptrue();
2791 
2792   __ leave();
2793 
2794   // check for pending exceptions
2795 #ifdef ASSERT
2796   Label L;
2797   __ ldr(rscratch1, Address(rthread, Thread::pending_exception_offset()));
2798   __ cbnz(rscratch1, L);
2799   __ should_not_reach_here();
2800   __ bind(L);
2801 #endif // ASSERT
2802   __ far_jump(RuntimeAddress(StubRoutines::forward_exception_entry()));
2803 
2804   // codeBlob framesize is in words (not VMRegImpl::slot_size)
2805   RuntimeStub* stub =
2806     RuntimeStub::new_runtime_stub(name,
2807                                   &code,
2808                                   frame_complete,
2809                                   (framesize >> (LogBytesPerWord - LogBytesPerInt)),
2810                                   oop_maps, false);
2811   AOTCodeCache::store_code_blob(*stub, AOTCodeEntry::SharedBlob, StubInfo::blob(id));
2812 
2813   return stub;
2814 }
2815 
2816 #if INCLUDE_JFR
2817 
2818 static void jfr_prologue(address the_pc, MacroAssembler* masm, Register thread) {
2819   __ set_last_Java_frame(sp, rfp, the_pc, rscratch1);
2820   __ mov(c_rarg0, thread);
2821 }
2822 
2823 // The handle is dereferenced through a load barrier.
2824 static void jfr_epilogue(MacroAssembler* masm) {
2825   __ reset_last_Java_frame(true);
2826 }
2827 
2828 // For c2: c_rarg0 is junk, call to runtime to write a checkpoint.
2829 // It returns a jobject handle to the event writer.
2830 // The handle is dereferenced and the return value is the event writer oop.
2831 RuntimeStub* SharedRuntime::generate_jfr_write_checkpoint() {
2832   enum layout {
2833     rbp_off,
2834     rbpH_off,
2835     return_off,
2836     return_off2,
2837     framesize // inclusive of return address
2838   };
2839 
2840   int insts_size = 1024;
2841   int locs_size = 64;
2842   const char* name = SharedRuntime::stub_name(StubId::shared_jfr_write_checkpoint_id);
2843   CodeBuffer code(name, insts_size, locs_size);
2844   OopMapSet* oop_maps = new OopMapSet();
2845   MacroAssembler* masm = new MacroAssembler(&code);
2846 
2847   address start = __ pc();
2848   __ enter();
2849   int frame_complete = __ pc() - start;
2850   address the_pc = __ pc();
2851   jfr_prologue(the_pc, masm, rthread);
2852   __ call_VM_leaf(CAST_FROM_FN_PTR(address, JfrIntrinsicSupport::write_checkpoint), 1);
2853   jfr_epilogue(masm);
2854   __ resolve_global_jobject(r0, rscratch1, rscratch2);
2855   __ leave();
2856   __ ret(lr);
2857 
2858   OopMap* map = new OopMap(framesize, 1); // rfp
2859   oop_maps->add_gc_map(the_pc - start, map);
2860 
2861   RuntimeStub* stub = // codeBlob framesize is in words (not VMRegImpl::slot_size)
2862     RuntimeStub::new_runtime_stub(name, &code, frame_complete,
2863                                   (framesize >> (LogBytesPerWord - LogBytesPerInt)),
2864                                   oop_maps, false);
2865   return stub;
2866 }
2867 
2868 // For c2: call to return a leased buffer.
2869 RuntimeStub* SharedRuntime::generate_jfr_return_lease() {
2870   enum layout {
2871     rbp_off,
2872     rbpH_off,
2873     return_off,
2874     return_off2,
2875     framesize // inclusive of return address
2876   };
2877 
2878   int insts_size = 1024;
2879   int locs_size = 64;
2880 
2881   const char* name = SharedRuntime::stub_name(StubId::shared_jfr_return_lease_id);
2882   CodeBuffer code(name, insts_size, locs_size);
2883   OopMapSet* oop_maps = new OopMapSet();
2884   MacroAssembler* masm = new MacroAssembler(&code);
2885 
2886   address start = __ pc();
2887   __ enter();
2888   int frame_complete = __ pc() - start;
2889   address the_pc = __ pc();
2890   jfr_prologue(the_pc, masm, rthread);
2891   __ call_VM_leaf(CAST_FROM_FN_PTR(address, JfrIntrinsicSupport::return_lease), 1);
2892   jfr_epilogue(masm);
2893 
2894   __ leave();
2895   __ ret(lr);
2896 
2897   OopMap* map = new OopMap(framesize, 1); // rfp
2898   oop_maps->add_gc_map(the_pc - start, map);
2899 
2900   RuntimeStub* stub = // codeBlob framesize is in words (not VMRegImpl::slot_size)
2901     RuntimeStub::new_runtime_stub(name, &code, frame_complete,
2902                                   (framesize >> (LogBytesPerWord - LogBytesPerInt)),
2903                                   oop_maps, false);
2904   return stub;
2905 }
2906 
2907 #endif // INCLUDE_JFR