1 /*
   2  * Copyright (c) 1997, 2024, Oracle and/or its affiliates. All rights reserved.
   3  * Copyright (c) 2014, 2024, Red Hat Inc. All rights reserved.
   4  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   5  *
   6  * This code is free software; you can redistribute it and/or modify it
   7  * under the terms of the GNU General Public License version 2 only, as
   8  * published by the Free Software Foundation.
   9  *
  10  * This code is distributed in the hope that it will be useful, but WITHOUT
  11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  13  * version 2 for more details (a copy is included in the LICENSE file that
  14  * accompanied this code).
  15  *
  16  * You should have received a copy of the GNU General Public License version
  17  * 2 along with this work; if not, write to the Free Software Foundation,
  18  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  19  *
  20  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  21  * or visit www.oracle.com if you need additional information or have any
  22  * questions.
  23  *
  24  */
  25 
  26 #ifndef CPU_AARCH64_MACROASSEMBLER_AARCH64_HPP
  27 #define CPU_AARCH64_MACROASSEMBLER_AARCH64_HPP
  28 
  29 #include "asm/assembler.inline.hpp"
  30 #include "code/vmreg.hpp"
  31 #include "code/SCCache.hpp"
  32 #include "metaprogramming/enableIf.hpp"
  33 #include "oops/compressedOops.hpp"
  34 #include "oops/compressedKlass.hpp"
  35 #include "runtime/vm_version.hpp"
  36 #include "utilities/powerOfTwo.hpp"
  37 
  38 class OopMap;
  39 
  40 // MacroAssembler extends Assembler by frequently used macros.
  41 //
  42 // Instructions for which a 'better' code sequence exists depending
  43 // on arguments should also go in here.
  44 
  45 class MacroAssembler: public Assembler {
  46   friend class LIR_Assembler;
  47 
  48  public:
  49   using Assembler::mov;
  50   using Assembler::movi;
  51 
  52  protected:
  53 
  54   // Support for VM calls
  55   //
  56   // This is the base routine called by the different versions of call_VM_leaf. The interpreter
  57   // may customize this version by overriding it for its purposes (e.g., to save/restore
  58   // additional registers when doing a VM call).
  59   virtual void call_VM_leaf_base(
  60     address entry_point,               // the entry point
  61     int     number_of_arguments,        // the number of arguments to pop after the call
  62     Label *retaddr = nullptr
  63   );
  64 
  65   virtual void call_VM_leaf_base(
  66     address entry_point,               // the entry point
  67     int     number_of_arguments,        // the number of arguments to pop after the call
  68     Label &retaddr) {
  69     call_VM_leaf_base(entry_point, number_of_arguments, &retaddr);
  70   }
  71 
  72   // This is the base routine called by the different versions of call_VM. The interpreter
  73   // may customize this version by overriding it for its purposes (e.g., to save/restore
  74   // additional registers when doing a VM call).
  75   //
  76   // If no java_thread register is specified (noreg) than rthread will be used instead. call_VM_base
  77   // returns the register which contains the thread upon return. If a thread register has been
  78   // specified, the return value will correspond to that register. If no last_java_sp is specified
  79   // (noreg) than rsp will be used instead.
  80   virtual void call_VM_base(           // returns the register containing the thread upon return
  81     Register oop_result,               // where an oop-result ends up if any; use noreg otherwise
  82     Register java_thread,              // the thread if computed before     ; use noreg otherwise
  83     Register last_java_sp,             // to set up last_Java_frame in stubs; use noreg otherwise
  84     address  entry_point,              // the entry point
  85     int      number_of_arguments,      // the number of arguments (w/o thread) to pop after the call
  86     bool     check_exceptions          // whether to check for pending exceptions after return
  87   );
  88 
  89   void call_VM_helper(Register oop_result, address entry_point, int number_of_arguments, bool check_exceptions = true);
  90 
  91   enum KlassDecodeMode {
  92     KlassDecodeNone,
  93     KlassDecodeZero,
  94     KlassDecodeXor,
  95     KlassDecodeMovk
  96   };
  97 
  98   KlassDecodeMode klass_decode_mode();
  99 
 100  private:
 101   static KlassDecodeMode _klass_decode_mode;
 102 
 103  public:
 104   MacroAssembler(CodeBuffer* code) : Assembler(code) {}
 105 
 106  // These routines should emit JVMTI PopFrame and ForceEarlyReturn handling code.
 107  // The implementation is only non-empty for the InterpreterMacroAssembler,
 108  // as only the interpreter handles PopFrame and ForceEarlyReturn requests.
 109  virtual void check_and_handle_popframe(Register java_thread);
 110  virtual void check_and_handle_earlyret(Register java_thread);
 111 
 112   void safepoint_poll(Label& slow_path, bool at_return, bool acquire, bool in_nmethod, Register tmp = rscratch1);
 113   void rt_call(address dest, Register tmp = rscratch1);
 114 
 115   // Load Effective Address
 116   void lea(Register r, const Address &a) {
 117     InstructionMark im(this);
 118     a.lea(this, r);
 119   }
 120 
 121   /* Sometimes we get misaligned loads and stores, usually from Unsafe
 122      accesses, and these can exceed the offset range. */
 123   Address legitimize_address(const Address &a, int size, Register scratch) {
 124     if (a.getMode() == Address::base_plus_offset) {
 125       if (! Address::offset_ok_for_immed(a.offset(), exact_log2(size))) {
 126         block_comment("legitimize_address {");
 127         lea(scratch, a);
 128         block_comment("} legitimize_address");
 129         return Address(scratch);
 130       }
 131     }
 132     return a;
 133   }
 134 
 135   void addmw(Address a, Register incr, Register scratch) {
 136     ldrw(scratch, a);
 137     addw(scratch, scratch, incr);
 138     strw(scratch, a);
 139   }
 140 
 141   // Add constant to memory word
 142   void addmw(Address a, int imm, Register scratch) {
 143     ldrw(scratch, a);
 144     if (imm > 0)
 145       addw(scratch, scratch, (unsigned)imm);
 146     else
 147       subw(scratch, scratch, (unsigned)-imm);
 148     strw(scratch, a);
 149   }
 150 
 151   void bind(Label& L) {
 152     Assembler::bind(L);
 153     code()->clear_last_insn();
 154     code()->set_last_label(pc());
 155   }
 156 
 157   void membar(Membar_mask_bits order_constraint);
 158 
 159   using Assembler::ldr;
 160   using Assembler::str;
 161   using Assembler::ldrw;
 162   using Assembler::strw;
 163 
 164   void ldr(Register Rx, const Address &adr);
 165   void ldrw(Register Rw, const Address &adr);
 166   void str(Register Rx, const Address &adr);
 167   void strw(Register Rx, const Address &adr);
 168 
 169   // Frame creation and destruction shared between JITs.
 170   void build_frame(int framesize);
 171   void remove_frame(int framesize);
 172 
 173   virtual void _call_Unimplemented(address call_site) {
 174     mov(rscratch2, call_site);
 175   }
 176 
 177 // Microsoft's MSVC team thinks that the __FUNCSIG__ is approximately (sympathy for calling conventions) equivalent to __PRETTY_FUNCTION__
 178 // Also, from Clang patch: "It is very similar to GCC's PRETTY_FUNCTION, except it prints the calling convention."
 179 // https://reviews.llvm.org/D3311
 180 
 181 #ifdef _WIN64
 182 #define call_Unimplemented() _call_Unimplemented((address)__FUNCSIG__)
 183 #else
 184 #define call_Unimplemented() _call_Unimplemented((address)__PRETTY_FUNCTION__)
 185 #endif
 186 
 187   // aliases defined in AARCH64 spec
 188 
 189   template<class T>
 190   inline void cmpw(Register Rd, T imm)  { subsw(zr, Rd, imm); }
 191 
 192   inline void cmp(Register Rd, unsigned char imm8)  { subs(zr, Rd, imm8); }
 193   inline void cmp(Register Rd, unsigned imm) = delete;
 194 
 195   template<class T>
 196   inline void cmnw(Register Rd, T imm) { addsw(zr, Rd, imm); }
 197 
 198   inline void cmn(Register Rd, unsigned char imm8)  { adds(zr, Rd, imm8); }
 199   inline void cmn(Register Rd, unsigned imm) = delete;
 200 
 201   void cset(Register Rd, Assembler::Condition cond) {
 202     csinc(Rd, zr, zr, ~cond);
 203   }
 204   void csetw(Register Rd, Assembler::Condition cond) {
 205     csincw(Rd, zr, zr, ~cond);
 206   }
 207 
 208   void cneg(Register Rd, Register Rn, Assembler::Condition cond) {
 209     csneg(Rd, Rn, Rn, ~cond);
 210   }
 211   void cnegw(Register Rd, Register Rn, Assembler::Condition cond) {
 212     csnegw(Rd, Rn, Rn, ~cond);
 213   }
 214 
 215   inline void movw(Register Rd, Register Rn) {
 216     if (Rd == sp || Rn == sp) {
 217       Assembler::addw(Rd, Rn, 0U);
 218     } else {
 219       orrw(Rd, zr, Rn);
 220     }
 221   }
 222   inline void mov(Register Rd, Register Rn) {
 223     assert(Rd != r31_sp && Rn != r31_sp, "should be");
 224     if (Rd == Rn) {
 225     } else if (Rd == sp || Rn == sp) {
 226       Assembler::add(Rd, Rn, 0U);
 227     } else {
 228       orr(Rd, zr, Rn);
 229     }
 230   }
 231 
 232   inline void moviw(Register Rd, unsigned imm) { orrw(Rd, zr, imm); }
 233   inline void movi(Register Rd, unsigned imm) { orr(Rd, zr, imm); }
 234 
 235   inline void tstw(Register Rd, Register Rn) { andsw(zr, Rd, Rn); }
 236   inline void tst(Register Rd, Register Rn) { ands(zr, Rd, Rn); }
 237 
 238   inline void tstw(Register Rd, uint64_t imm) { andsw(zr, Rd, imm); }
 239   inline void tst(Register Rd, uint64_t imm) { ands(zr, Rd, imm); }
 240 
 241   inline void bfiw(Register Rd, Register Rn, unsigned lsb, unsigned width) {
 242     bfmw(Rd, Rn, ((32 - lsb) & 31), (width - 1));
 243   }
 244   inline void bfi(Register Rd, Register Rn, unsigned lsb, unsigned width) {
 245     bfm(Rd, Rn, ((64 - lsb) & 63), (width - 1));
 246   }
 247 
 248   inline void bfxilw(Register Rd, Register Rn, unsigned lsb, unsigned width) {
 249     bfmw(Rd, Rn, lsb, (lsb + width - 1));
 250   }
 251   inline void bfxil(Register Rd, Register Rn, unsigned lsb, unsigned width) {
 252     bfm(Rd, Rn, lsb , (lsb + width - 1));
 253   }
 254 
 255   inline void sbfizw(Register Rd, Register Rn, unsigned lsb, unsigned width) {
 256     sbfmw(Rd, Rn, ((32 - lsb) & 31), (width - 1));
 257   }
 258   inline void sbfiz(Register Rd, Register Rn, unsigned lsb, unsigned width) {
 259     sbfm(Rd, Rn, ((64 - lsb) & 63), (width - 1));
 260   }
 261 
 262   inline void sbfxw(Register Rd, Register Rn, unsigned lsb, unsigned width) {
 263     sbfmw(Rd, Rn, lsb, (lsb + width - 1));
 264   }
 265   inline void sbfx(Register Rd, Register Rn, unsigned lsb, unsigned width) {
 266     sbfm(Rd, Rn, lsb , (lsb + width - 1));
 267   }
 268 
 269   inline void ubfizw(Register Rd, Register Rn, unsigned lsb, unsigned width) {
 270     ubfmw(Rd, Rn, ((32 - lsb) & 31), (width - 1));
 271   }
 272   inline void ubfiz(Register Rd, Register Rn, unsigned lsb, unsigned width) {
 273     ubfm(Rd, Rn, ((64 - lsb) & 63), (width - 1));
 274   }
 275 
 276   inline void ubfxw(Register Rd, Register Rn, unsigned lsb, unsigned width) {
 277     ubfmw(Rd, Rn, lsb, (lsb + width - 1));
 278   }
 279   inline void ubfx(Register Rd, Register Rn, unsigned lsb, unsigned width) {
 280     ubfm(Rd, Rn, lsb , (lsb + width - 1));
 281   }
 282 
 283   inline void asrw(Register Rd, Register Rn, unsigned imm) {
 284     sbfmw(Rd, Rn, imm, 31);
 285   }
 286 
 287   inline void asr(Register Rd, Register Rn, unsigned imm) {
 288     sbfm(Rd, Rn, imm, 63);
 289   }
 290 
 291   inline void lslw(Register Rd, Register Rn, unsigned imm) {
 292     ubfmw(Rd, Rn, ((32 - imm) & 31), (31 - imm));
 293   }
 294 
 295   inline void lsl(Register Rd, Register Rn, unsigned imm) {
 296     ubfm(Rd, Rn, ((64 - imm) & 63), (63 - imm));
 297   }
 298 
 299   inline void lsrw(Register Rd, Register Rn, unsigned imm) {
 300     ubfmw(Rd, Rn, imm, 31);
 301   }
 302 
 303   inline void lsr(Register Rd, Register Rn, unsigned imm) {
 304     ubfm(Rd, Rn, imm, 63);
 305   }
 306 
 307   inline void rorw(Register Rd, Register Rn, unsigned imm) {
 308     extrw(Rd, Rn, Rn, imm);
 309   }
 310 
 311   inline void ror(Register Rd, Register Rn, unsigned imm) {
 312     extr(Rd, Rn, Rn, imm);
 313   }
 314 
 315   inline void sxtbw(Register Rd, Register Rn) {
 316     sbfmw(Rd, Rn, 0, 7);
 317   }
 318   inline void sxthw(Register Rd, Register Rn) {
 319     sbfmw(Rd, Rn, 0, 15);
 320   }
 321   inline void sxtb(Register Rd, Register Rn) {
 322     sbfm(Rd, Rn, 0, 7);
 323   }
 324   inline void sxth(Register Rd, Register Rn) {
 325     sbfm(Rd, Rn, 0, 15);
 326   }
 327   inline void sxtw(Register Rd, Register Rn) {
 328     sbfm(Rd, Rn, 0, 31);
 329   }
 330 
 331   inline void uxtbw(Register Rd, Register Rn) {
 332     ubfmw(Rd, Rn, 0, 7);
 333   }
 334   inline void uxthw(Register Rd, Register Rn) {
 335     ubfmw(Rd, Rn, 0, 15);
 336   }
 337   inline void uxtb(Register Rd, Register Rn) {
 338     ubfm(Rd, Rn, 0, 7);
 339   }
 340   inline void uxth(Register Rd, Register Rn) {
 341     ubfm(Rd, Rn, 0, 15);
 342   }
 343   inline void uxtw(Register Rd, Register Rn) {
 344     ubfm(Rd, Rn, 0, 31);
 345   }
 346 
 347   inline void cmnw(Register Rn, Register Rm) {
 348     addsw(zr, Rn, Rm);
 349   }
 350   inline void cmn(Register Rn, Register Rm) {
 351     adds(zr, Rn, Rm);
 352   }
 353 
 354   inline void cmpw(Register Rn, Register Rm) {
 355     subsw(zr, Rn, Rm);
 356   }
 357   inline void cmp(Register Rn, Register Rm) {
 358     subs(zr, Rn, Rm);
 359   }
 360 
 361   inline void negw(Register Rd, Register Rn) {
 362     subw(Rd, zr, Rn);
 363   }
 364 
 365   inline void neg(Register Rd, Register Rn) {
 366     sub(Rd, zr, Rn);
 367   }
 368 
 369   inline void negsw(Register Rd, Register Rn) {
 370     subsw(Rd, zr, Rn);
 371   }
 372 
 373   inline void negs(Register Rd, Register Rn) {
 374     subs(Rd, zr, Rn);
 375   }
 376 
 377   inline void cmnw(Register Rn, Register Rm, enum shift_kind kind, unsigned shift = 0) {
 378     addsw(zr, Rn, Rm, kind, shift);
 379   }
 380   inline void cmn(Register Rn, Register Rm, enum shift_kind kind, unsigned shift = 0) {
 381     adds(zr, Rn, Rm, kind, shift);
 382   }
 383 
 384   inline void cmpw(Register Rn, Register Rm, enum shift_kind kind, unsigned shift = 0) {
 385     subsw(zr, Rn, Rm, kind, shift);
 386   }
 387   inline void cmp(Register Rn, Register Rm, enum shift_kind kind, unsigned shift = 0) {
 388     subs(zr, Rn, Rm, kind, shift);
 389   }
 390 
 391   inline void negw(Register Rd, Register Rn, enum shift_kind kind, unsigned shift = 0) {
 392     subw(Rd, zr, Rn, kind, shift);
 393   }
 394 
 395   inline void neg(Register Rd, Register Rn, enum shift_kind kind, unsigned shift = 0) {
 396     sub(Rd, zr, Rn, kind, shift);
 397   }
 398 
 399   inline void negsw(Register Rd, Register Rn, enum shift_kind kind, unsigned shift = 0) {
 400     subsw(Rd, zr, Rn, kind, shift);
 401   }
 402 
 403   inline void negs(Register Rd, Register Rn, enum shift_kind kind, unsigned shift = 0) {
 404     subs(Rd, zr, Rn, kind, shift);
 405   }
 406 
 407   inline void mnegw(Register Rd, Register Rn, Register Rm) {
 408     msubw(Rd, Rn, Rm, zr);
 409   }
 410   inline void mneg(Register Rd, Register Rn, Register Rm) {
 411     msub(Rd, Rn, Rm, zr);
 412   }
 413 
 414   inline void mulw(Register Rd, Register Rn, Register Rm) {
 415     maddw(Rd, Rn, Rm, zr);
 416   }
 417   inline void mul(Register Rd, Register Rn, Register Rm) {
 418     madd(Rd, Rn, Rm, zr);
 419   }
 420 
 421   inline void smnegl(Register Rd, Register Rn, Register Rm) {
 422     smsubl(Rd, Rn, Rm, zr);
 423   }
 424   inline void smull(Register Rd, Register Rn, Register Rm) {
 425     smaddl(Rd, Rn, Rm, zr);
 426   }
 427 
 428   inline void umnegl(Register Rd, Register Rn, Register Rm) {
 429     umsubl(Rd, Rn, Rm, zr);
 430   }
 431   inline void umull(Register Rd, Register Rn, Register Rm) {
 432     umaddl(Rd, Rn, Rm, zr);
 433   }
 434 
 435 #define WRAP(INSN)                                                            \
 436   void INSN(Register Rd, Register Rn, Register Rm, Register Ra) {             \
 437     if (VM_Version::supports_a53mac() && Ra != zr)                            \
 438       nop();                                                                  \
 439     Assembler::INSN(Rd, Rn, Rm, Ra);                                          \
 440   }
 441 
 442   WRAP(madd) WRAP(msub) WRAP(maddw) WRAP(msubw)
 443   WRAP(smaddl) WRAP(smsubl) WRAP(umaddl) WRAP(umsubl)
 444 #undef WRAP
 445 
 446 
 447   // macro assembly operations needed for aarch64
 448 
 449 public:
 450 
 451   enum FpPushPopMode {
 452     PushPopFull,
 453     PushPopSVE,
 454     PushPopNeon,
 455     PushPopFp
 456   };
 457 
 458   // first two private routines for loading 32 bit or 64 bit constants
 459 private:
 460 
 461   void mov_immediate64(Register dst, uint64_t imm64);
 462   void mov_immediate32(Register dst, uint32_t imm32);
 463 
 464   int push(unsigned int bitset, Register stack);
 465   int pop(unsigned int bitset, Register stack);
 466 
 467   int push_fp(unsigned int bitset, Register stack, FpPushPopMode mode);
 468   int pop_fp(unsigned int bitset, Register stack, FpPushPopMode mode);
 469 
 470   int push_p(unsigned int bitset, Register stack);
 471   int pop_p(unsigned int bitset, Register stack);
 472 
 473   void mov(Register dst, Address a);
 474 
 475 public:
 476 
 477   void push(RegSet regs, Register stack) { if (regs.bits()) push(regs.bits(), stack); }
 478   void pop(RegSet regs, Register stack) { if (regs.bits()) pop(regs.bits(), stack); }
 479 
 480   void push_fp(FloatRegSet regs, Register stack, FpPushPopMode mode = PushPopFull) { if (regs.bits()) push_fp(regs.bits(), stack, mode); }
 481   void pop_fp(FloatRegSet regs, Register stack, FpPushPopMode mode = PushPopFull) { if (regs.bits()) pop_fp(regs.bits(), stack, mode); }
 482 
 483   static RegSet call_clobbered_gp_registers();
 484 
 485   void push_p(PRegSet regs, Register stack) { if (regs.bits()) push_p(regs.bits(), stack); }
 486   void pop_p(PRegSet regs, Register stack) { if (regs.bits()) pop_p(regs.bits(), stack); }
 487 
 488   // Push and pop everything that might be clobbered by a native
 489   // runtime call except rscratch1 and rscratch2.  (They are always
 490   // scratch, so we don't have to protect them.)  Only save the lower
 491   // 64 bits of each vector register. Additional registers can be excluded
 492   // in a passed RegSet.
 493   void push_call_clobbered_registers_except(RegSet exclude);
 494   void pop_call_clobbered_registers_except(RegSet exclude);
 495 
 496   void push_call_clobbered_registers() {
 497     push_call_clobbered_registers_except(RegSet());
 498   }
 499   void pop_call_clobbered_registers() {
 500     pop_call_clobbered_registers_except(RegSet());
 501   }
 502 
 503 
 504   // now mov instructions for loading absolute addresses and 32 or
 505   // 64 bit integers
 506 
 507   inline void mov(Register dst, address addr)             { mov_immediate64(dst, (uint64_t)addr); }
 508 
 509   template<typename T, ENABLE_IF(std::is_integral<T>::value)>
 510   inline void mov(Register dst, T o)                      { mov_immediate64(dst, (uint64_t)o); }
 511 
 512   inline void movw(Register dst, uint32_t imm32)          { mov_immediate32(dst, imm32); }
 513 
 514   void mov(Register dst, RegisterOrConstant src) {
 515     if (src.is_register())
 516       mov(dst, src.as_register());
 517     else
 518       mov(dst, src.as_constant());
 519   }
 520 
 521   void movptr(Register r, uintptr_t imm64);
 522 
 523   void mov(FloatRegister Vd, SIMD_Arrangement T, uint64_t imm64);
 524 
 525   void mov(FloatRegister Vd, SIMD_Arrangement T, FloatRegister Vn) {
 526     orr(Vd, T, Vn, Vn);
 527   }
 528 
 529   void flt_to_flt16(Register dst, FloatRegister src, FloatRegister tmp) {
 530     fcvtsh(tmp, src);
 531     smov(dst, tmp, H, 0);
 532   }
 533 
 534   void flt16_to_flt(FloatRegister dst, Register src, FloatRegister tmp) {
 535     mov(tmp, H, 0, src);
 536     fcvths(dst, tmp);
 537   }
 538 
 539   // Generalized Test Bit And Branch, including a "far" variety which
 540   // spans more than 32KiB.
 541   void tbr(Condition cond, Register Rt, int bitpos, Label &dest, bool isfar = false) {
 542     assert(cond == EQ || cond == NE, "must be");
 543 
 544     if (isfar)
 545       cond = ~cond;
 546 
 547     void (Assembler::* branch)(Register Rt, int bitpos, Label &L);
 548     if (cond == Assembler::EQ)
 549       branch = &Assembler::tbz;
 550     else
 551       branch = &Assembler::tbnz;
 552 
 553     if (isfar) {
 554       Label L;
 555       (this->*branch)(Rt, bitpos, L);
 556       b(dest);
 557       bind(L);
 558     } else {
 559       (this->*branch)(Rt, bitpos, dest);
 560     }
 561   }
 562 
 563   // macro instructions for accessing and updating floating point
 564   // status register
 565   //
 566   // FPSR : op1 == 011
 567   //        CRn == 0100
 568   //        CRm == 0100
 569   //        op2 == 001
 570 
 571   inline void get_fpsr(Register reg)
 572   {
 573     mrs(0b11, 0b0100, 0b0100, 0b001, reg);
 574   }
 575 
 576   inline void set_fpsr(Register reg)
 577   {
 578     msr(0b011, 0b0100, 0b0100, 0b001, reg);
 579   }
 580 
 581   inline void clear_fpsr()
 582   {
 583     msr(0b011, 0b0100, 0b0100, 0b001, zr);
 584   }
 585 
 586   // FPCR : op1 == 011
 587   //        CRn == 0100
 588   //        CRm == 0100
 589   //        op2 == 000
 590 
 591   inline void get_fpcr(Register reg) {
 592     mrs(0b11, 0b0100, 0b0100, 0b000, reg);
 593   }
 594 
 595   inline void set_fpcr(Register reg) {
 596     msr(0b011, 0b0100, 0b0100, 0b000, reg);
 597   }
 598 
 599   // DCZID_EL0: op1 == 011
 600   //            CRn == 0000
 601   //            CRm == 0000
 602   //            op2 == 111
 603   inline void get_dczid_el0(Register reg)
 604   {
 605     mrs(0b011, 0b0000, 0b0000, 0b111, reg);
 606   }
 607 
 608   // CTR_EL0:   op1 == 011
 609   //            CRn == 0000
 610   //            CRm == 0000
 611   //            op2 == 001
 612   inline void get_ctr_el0(Register reg)
 613   {
 614     mrs(0b011, 0b0000, 0b0000, 0b001, reg);
 615   }
 616 
 617   inline void get_nzcv(Register reg) {
 618     mrs(0b011, 0b0100, 0b0010, 0b000, reg);
 619   }
 620 
 621   inline void set_nzcv(Register reg) {
 622     msr(0b011, 0b0100, 0b0010, 0b000, reg);
 623   }
 624 
 625   // idiv variant which deals with MINLONG as dividend and -1 as divisor
 626   int corrected_idivl(Register result, Register ra, Register rb,
 627                       bool want_remainder, Register tmp = rscratch1);
 628   int corrected_idivq(Register result, Register ra, Register rb,
 629                       bool want_remainder, Register tmp = rscratch1);
 630 
 631   // Support for null-checks
 632   //
 633   // Generates code that causes a null OS exception if the content of reg is null.
 634   // If the accessed location is M[reg + offset] and the offset is known, provide the
 635   // offset. No explicit code generation is needed if the offset is within a certain
 636   // range (0 <= offset <= page_size).
 637 
 638   virtual void null_check(Register reg, int offset = -1);
 639   static bool needs_explicit_null_check(intptr_t offset);
 640   static bool uses_implicit_null_check(void* address);
 641 
 642   static address target_addr_for_insn(address insn_addr, unsigned insn);
 643   static address target_addr_for_insn_or_null(address insn_addr, unsigned insn);
 644   static address target_addr_for_insn(address insn_addr) {
 645     unsigned insn = *(unsigned*)insn_addr;
 646     return target_addr_for_insn(insn_addr, insn);
 647   }
 648   static address target_addr_for_insn_or_null(address insn_addr) {
 649     unsigned insn = *(unsigned*)insn_addr;
 650     return target_addr_for_insn_or_null(insn_addr, insn);
 651   }
 652 
 653   // Required platform-specific helpers for Label::patch_instructions.
 654   // They _shadow_ the declarations in AbstractAssembler, which are undefined.
 655   static int pd_patch_instruction_size(address branch, address target);
 656   static void pd_patch_instruction(address branch, address target, const char* file = nullptr, int line = 0) {
 657     pd_patch_instruction_size(branch, target);
 658   }
 659   static address pd_call_destination(address branch) {
 660     return target_addr_for_insn(branch);
 661   }
 662 #ifndef PRODUCT
 663   static void pd_print_patched_instruction(address branch);
 664 #endif
 665 
 666   static int patch_oop(address insn_addr, address o);
 667   static int patch_narrow_klass(address insn_addr, narrowKlass n);
 668 
 669   // Return whether code is emitted to a scratch blob.
 670   virtual bool in_scratch_emit_size() {
 671     return false;
 672   }
 673   address emit_trampoline_stub(int insts_call_instruction_offset, address target);
 674   static int max_trampoline_stub_size();
 675   void emit_static_call_stub();
 676   static int static_call_stub_size();
 677 
 678   // The following 4 methods return the offset of the appropriate move instruction
 679 
 680   // Support for fast byte/short loading with zero extension (depending on particular CPU)
 681   int load_unsigned_byte(Register dst, Address src);
 682   int load_unsigned_short(Register dst, Address src);
 683 
 684   // Support for fast byte/short loading with sign extension (depending on particular CPU)
 685   int load_signed_byte(Register dst, Address src);
 686   int load_signed_short(Register dst, Address src);
 687 
 688   int load_signed_byte32(Register dst, Address src);
 689   int load_signed_short32(Register dst, Address src);
 690 
 691   // Support for sign-extension (hi:lo = extend_sign(lo))
 692   void extend_sign(Register hi, Register lo);
 693 
 694   // Load and store values by size and signed-ness
 695   void load_sized_value(Register dst, Address src, size_t size_in_bytes, bool is_signed);
 696   void store_sized_value(Address dst, Register src, size_t size_in_bytes);
 697 
 698   // Support for inc/dec with optimal instruction selection depending on value
 699 
 700   // x86_64 aliases an unqualified register/address increment and
 701   // decrement to call incrementq and decrementq but also supports
 702   // explicitly sized calls to incrementq/decrementq or
 703   // incrementl/decrementl
 704 
 705   // for aarch64 the proper convention would be to use
 706   // increment/decrement for 64 bit operations and
 707   // incrementw/decrementw for 32 bit operations. so when porting
 708   // x86_64 code we can leave calls to increment/decrement as is,
 709   // replace incrementq/decrementq with increment/decrement and
 710   // replace incrementl/decrementl with incrementw/decrementw.
 711 
 712   // n.b. increment/decrement calls with an Address destination will
 713   // need to use a scratch register to load the value to be
 714   // incremented. increment/decrement calls which add or subtract a
 715   // constant value greater than 2^12 will need to use a 2nd scratch
 716   // register to hold the constant. so, a register increment/decrement
 717   // may trash rscratch2 and an address increment/decrement trash
 718   // rscratch and rscratch2
 719 
 720   void decrementw(Address dst, int value = 1);
 721   void decrementw(Register reg, int value = 1);
 722 
 723   void decrement(Register reg, int value = 1);
 724   void decrement(Address dst, int value = 1);
 725 
 726   void incrementw(Address dst, int value = 1);
 727   void incrementw(Register reg, int value = 1);
 728 
 729   void increment(Register reg, int value = 1);
 730   void increment(Address dst, int value = 1);
 731 
 732 
 733   // Alignment
 734   void align(int modulus);
 735   void align(int modulus, int target);
 736 
 737   // nop
 738   void post_call_nop();
 739 
 740   // Stack frame creation/removal
 741   void enter(bool strip_ret_addr = false);
 742   void leave();
 743 
 744   // ROP Protection
 745   void protect_return_address();
 746   void protect_return_address(Register return_reg);
 747   void authenticate_return_address();
 748   void authenticate_return_address(Register return_reg);
 749   void strip_return_address();
 750   void check_return_address(Register return_reg=lr) PRODUCT_RETURN;
 751 
 752   // Support for getting the JavaThread pointer (i.e.; a reference to thread-local information)
 753   // The pointer will be loaded into the thread register.
 754   void get_thread(Register thread);
 755 
 756   // support for argument shuffling
 757   void move32_64(VMRegPair src, VMRegPair dst, Register tmp = rscratch1);
 758   void float_move(VMRegPair src, VMRegPair dst, Register tmp = rscratch1);
 759   void long_move(VMRegPair src, VMRegPair dst, Register tmp = rscratch1);
 760   void double_move(VMRegPair src, VMRegPair dst, Register tmp = rscratch1);
 761   void object_move(
 762                    OopMap* map,
 763                    int oop_handle_offset,
 764                    int framesize_in_slots,
 765                    VMRegPair src,
 766                    VMRegPair dst,
 767                    bool is_receiver,
 768                    int* receiver_offset);
 769 
 770 
 771   // Support for VM calls
 772   //
 773   // It is imperative that all calls into the VM are handled via the call_VM macros.
 774   // They make sure that the stack linkage is setup correctly. call_VM's correspond
 775   // to ENTRY/ENTRY_X entry points while call_VM_leaf's correspond to LEAF entry points.
 776 
 777 
 778   void call_VM(Register oop_result,
 779                address entry_point,
 780                bool check_exceptions = true);
 781   void call_VM(Register oop_result,
 782                address entry_point,
 783                Register arg_1,
 784                bool check_exceptions = true);
 785   void call_VM(Register oop_result,
 786                address entry_point,
 787                Register arg_1, Register arg_2,
 788                bool check_exceptions = true);
 789   void call_VM(Register oop_result,
 790                address entry_point,
 791                Register arg_1, Register arg_2, Register arg_3,
 792                bool check_exceptions = true);
 793 
 794   // Overloadings with last_Java_sp
 795   void call_VM(Register oop_result,
 796                Register last_java_sp,
 797                address entry_point,
 798                int number_of_arguments = 0,
 799                bool check_exceptions = true);
 800   void call_VM(Register oop_result,
 801                Register last_java_sp,
 802                address entry_point,
 803                Register arg_1, bool
 804                check_exceptions = true);
 805   void call_VM(Register oop_result,
 806                Register last_java_sp,
 807                address entry_point,
 808                Register arg_1, Register arg_2,
 809                bool check_exceptions = true);
 810   void call_VM(Register oop_result,
 811                Register last_java_sp,
 812                address entry_point,
 813                Register arg_1, Register arg_2, Register arg_3,
 814                bool check_exceptions = true);
 815 
 816   void get_vm_result  (Register oop_result, Register thread);
 817   void get_vm_result_2(Register metadata_result, Register thread);
 818 
 819   // These always tightly bind to MacroAssembler::call_VM_base
 820   // bypassing the virtual implementation
 821   void super_call_VM(Register oop_result, Register last_java_sp, address entry_point, int number_of_arguments = 0, bool check_exceptions = true);
 822   void super_call_VM(Register oop_result, Register last_java_sp, address entry_point, Register arg_1, bool check_exceptions = true);
 823   void super_call_VM(Register oop_result, Register last_java_sp, address entry_point, Register arg_1, Register arg_2, bool check_exceptions = true);
 824   void super_call_VM(Register oop_result, Register last_java_sp, address entry_point, Register arg_1, Register arg_2, Register arg_3, bool check_exceptions = true);
 825   void super_call_VM(Register oop_result, Register last_java_sp, address entry_point, Register arg_1, Register arg_2, Register arg_3, Register arg_4, bool check_exceptions = true);
 826 
 827   void call_VM_leaf(address entry_point,
 828                     int number_of_arguments = 0);
 829   void call_VM_leaf(address entry_point,
 830                     Register arg_1);
 831   void call_VM_leaf(address entry_point,
 832                     Register arg_1, Register arg_2);
 833   void call_VM_leaf(address entry_point,
 834                     Register arg_1, Register arg_2, Register arg_3);
 835 
 836   // These always tightly bind to MacroAssembler::call_VM_leaf_base
 837   // bypassing the virtual implementation
 838   void super_call_VM_leaf(address entry_point);
 839   void super_call_VM_leaf(address entry_point, Register arg_1);
 840   void super_call_VM_leaf(address entry_point, Register arg_1, Register arg_2);
 841   void super_call_VM_leaf(address entry_point, Register arg_1, Register arg_2, Register arg_3);
 842   void super_call_VM_leaf(address entry_point, Register arg_1, Register arg_2, Register arg_3, Register arg_4);
 843 
 844   // last Java Frame (fills frame anchor)
 845   void set_last_Java_frame(Register last_java_sp,
 846                            Register last_java_fp,
 847                            address last_java_pc,
 848                            Register scratch);
 849 
 850   void set_last_Java_frame(Register last_java_sp,
 851                            Register last_java_fp,
 852                            Label &last_java_pc,
 853                            Register scratch);
 854 
 855   void set_last_Java_frame(Register last_java_sp,
 856                            Register last_java_fp,
 857                            Register last_java_pc,
 858                            Register scratch);
 859 
 860   void reset_last_Java_frame(Register thread);
 861 
 862   // thread in the default location (rthread)
 863   void reset_last_Java_frame(bool clear_fp);
 864 
 865   // Stores
 866   void store_check(Register obj);                // store check for obj - register is destroyed afterwards
 867   void store_check(Register obj, Address dst);   // same as above, dst is exact store location (reg. is destroyed)
 868 
 869   void resolve_jobject(Register value, Register tmp1, Register tmp2);
 870   void resolve_global_jobject(Register value, Register tmp1, Register tmp2);
 871 
 872   // C 'boolean' to Java boolean: x == 0 ? 0 : 1
 873   void c2bool(Register x);
 874 
 875   void load_method_holder_cld(Register rresult, Register rmethod);
 876   void load_method_holder(Register holder, Register method);
 877 
 878   // oop manipulations
 879   void load_klass(Register dst, Register src);
 880   void store_klass(Register dst, Register src);
 881   void cmp_klass(Register oop, Register trial_klass, Register tmp);
 882 
 883   void resolve_weak_handle(Register result, Register tmp1, Register tmp2);
 884   void resolve_oop_handle(Register result, Register tmp1, Register tmp2);
 885   void load_mirror(Register dst, Register method, Register tmp1, Register tmp2);
 886 
 887   void access_load_at(BasicType type, DecoratorSet decorators, Register dst, Address src,
 888                       Register tmp1, Register tmp2);
 889 
 890   void access_store_at(BasicType type, DecoratorSet decorators, Address dst, Register val,
 891                        Register tmp1, Register tmp2, Register tmp3);
 892 
 893   void load_heap_oop(Register dst, Address src, Register tmp1,
 894                      Register tmp2, DecoratorSet decorators = 0);
 895 
 896   void load_heap_oop_not_null(Register dst, Address src, Register tmp1,
 897                               Register tmp2, DecoratorSet decorators = 0);
 898   void store_heap_oop(Address dst, Register val, Register tmp1,
 899                       Register tmp2, Register tmp3, DecoratorSet decorators = 0);
 900 
 901   // currently unimplemented
 902   // Used for storing null. All other oop constants should be
 903   // stored using routines that take a jobject.
 904   void store_heap_oop_null(Address dst);
 905 
 906   void store_klass_gap(Register dst, Register src);
 907 
 908   // This dummy is to prevent a call to store_heap_oop from
 909   // converting a zero (like null) into a Register by giving
 910   // the compiler two choices it can't resolve
 911 
 912   void store_heap_oop(Address dst, void* dummy);
 913 
 914   void encode_heap_oop(Register d, Register s);
 915   void encode_heap_oop(Register r) { encode_heap_oop(r, r); }
 916   void decode_heap_oop(Register d, Register s);
 917   void decode_heap_oop(Register r) { decode_heap_oop(r, r); }
 918   void encode_heap_oop_not_null(Register r);
 919   void decode_heap_oop_not_null(Register r);
 920   void encode_heap_oop_not_null(Register dst, Register src);
 921   void decode_heap_oop_not_null(Register dst, Register src);
 922 
 923   void set_narrow_oop(Register dst, jobject obj);
 924 
 925   void encode_klass_not_null(Register r);
 926   void decode_klass_not_null(Register r);
 927   void encode_klass_not_null(Register dst, Register src);
 928   void decode_klass_not_null(Register dst, Register src);
 929 
 930   void set_narrow_klass(Register dst, Klass* k);
 931 
 932   // if heap base register is used - reinit it with the correct value
 933   void reinit_heapbase();
 934 
 935   DEBUG_ONLY(void verify_heapbase(const char* msg);)
 936 
 937   void push_CPU_state(bool save_vectors = false, bool use_sve = false,
 938                       int sve_vector_size_in_bytes = 0, int total_predicate_in_bytes = 0);
 939   void pop_CPU_state(bool restore_vectors = false, bool use_sve = false,
 940                      int sve_vector_size_in_bytes = 0, int total_predicate_in_bytes = 0);
 941 
 942   void push_cont_fastpath(Register java_thread);
 943   void pop_cont_fastpath(Register java_thread);
 944 
 945   // Round up to a power of two
 946   void round_to(Register reg, int modulus);
 947 
 948   // java.lang.Math::round intrinsics
 949   void java_round_double(Register dst, FloatRegister src, FloatRegister ftmp);
 950   void java_round_float(Register dst, FloatRegister src, FloatRegister ftmp);
 951 
 952   // allocation
 953   void tlab_allocate(
 954     Register obj,                      // result: pointer to object after successful allocation
 955     Register var_size_in_bytes,        // object size in bytes if unknown at compile time; invalid otherwise
 956     int      con_size_in_bytes,        // object size in bytes if   known at compile time
 957     Register t1,                       // temp register
 958     Register t2,                       // temp register
 959     Label&   slow_case                 // continuation point if fast allocation fails
 960   );
 961   void verify_tlab();
 962 
 963   // interface method calling
 964   void lookup_interface_method(Register recv_klass,
 965                                Register intf_klass,
 966                                RegisterOrConstant itable_index,
 967                                Register method_result,
 968                                Register scan_temp,
 969                                Label& no_such_interface,
 970                    bool return_method = true);
 971 
 972   void lookup_interface_method_stub(Register recv_klass,
 973                                     Register holder_klass,
 974                                     Register resolved_klass,
 975                                     Register method_result,
 976                                     Register temp_reg,
 977                                     Register temp_reg2,
 978                                     int itable_index,
 979                                     Label& L_no_such_interface);
 980 
 981   // virtual method calling
 982   // n.b. x86 allows RegisterOrConstant for vtable_index
 983   void lookup_virtual_method(Register recv_klass,
 984                              RegisterOrConstant vtable_index,
 985                              Register method_result);
 986 
 987   // Test sub_klass against super_klass, with fast and slow paths.
 988 
 989   // The fast path produces a tri-state answer: yes / no / maybe-slow.
 990   // One of the three labels can be null, meaning take the fall-through.
 991   // If super_check_offset is -1, the value is loaded up from super_klass.
 992   // No registers are killed, except temp_reg.
 993   void check_klass_subtype_fast_path(Register sub_klass,
 994                                      Register super_klass,
 995                                      Register temp_reg,
 996                                      Label* L_success,
 997                                      Label* L_failure,
 998                                      Label* L_slow_path,
 999                 RegisterOrConstant super_check_offset = RegisterOrConstant(-1));
1000 
1001   // The rest of the type check; must be wired to a corresponding fast path.
1002   // It does not repeat the fast path logic, so don't use it standalone.
1003   // The temp_reg and temp2_reg can be noreg, if no temps are available.
1004   // Updates the sub's secondary super cache as necessary.
1005   // If set_cond_codes, condition codes will be Z on success, NZ on failure.
1006   void check_klass_subtype_slow_path(Register sub_klass,
1007                                      Register super_klass,
1008                                      Register temp_reg,
1009                                      Register temp2_reg,
1010                                      Label* L_success,
1011                                      Label* L_failure,
1012                                      bool set_cond_codes = false);
1013 
1014   // As above, but with a constant super_klass.
1015   // The result is in Register result, not the condition codes.
1016   bool lookup_secondary_supers_table(Register r_sub_klass,
1017                                      Register r_super_klass,
1018                                      Register temp1,
1019                                      Register temp2,
1020                                      Register temp3,
1021                                      FloatRegister vtemp,
1022                                      Register result,
1023                                      u1 super_klass_slot,
1024                                      bool stub_is_near = false);
1025 
1026   void verify_secondary_supers_table(Register r_sub_klass,
1027                                      Register r_super_klass,
1028                                      Register temp1,
1029                                      Register temp2,
1030                                      Register result);
1031 
1032   void lookup_secondary_supers_table_slow_path(Register r_super_klass,
1033                                                Register r_array_base,
1034                                                Register r_array_index,
1035                                                Register r_bitmap,
1036                                                Register temp1,
1037                                                Register result);
1038 
1039   // Simplified, combined version, good for typical uses.
1040   // Falls through on failure.
1041   void check_klass_subtype(Register sub_klass,
1042                            Register super_klass,
1043                            Register temp_reg,
1044                            Label& L_success);
1045 
1046   void clinit_barrier(Register klass,
1047                       Register thread,
1048                       Label* L_fast_path = nullptr,
1049                       Label* L_slow_path = nullptr);
1050 
1051   Address argument_address(RegisterOrConstant arg_slot, int extra_slot_offset = 0);
1052 
1053   void verify_sve_vector_length(Register tmp = rscratch1);
1054   void reinitialize_ptrue() {
1055     if (UseSVE > 0) {
1056       sve_ptrue(ptrue, B);
1057     }
1058   }
1059   void verify_ptrue();
1060 
1061   // Debugging
1062 
1063   // only if +VerifyOops
1064   void _verify_oop(Register reg, const char* s, const char* file, int line);
1065   void _verify_oop_addr(Address addr, const char * s, const char* file, int line);
1066 
1067   void _verify_oop_checked(Register reg, const char* s, const char* file, int line) {
1068     if (VerifyOops) {
1069       _verify_oop(reg, s, file, line);
1070     }
1071   }
1072   void _verify_oop_addr_checked(Address reg, const char* s, const char* file, int line) {
1073     if (VerifyOops) {
1074       _verify_oop_addr(reg, s, file, line);
1075     }
1076   }
1077 
1078 // TODO: verify method and klass metadata (compare against vptr?)
1079   void _verify_method_ptr(Register reg, const char * msg, const char * file, int line) {}
1080   void _verify_klass_ptr(Register reg, const char * msg, const char * file, int line){}
1081 
1082 #define verify_oop(reg) _verify_oop_checked(reg, "broken oop " #reg, __FILE__, __LINE__)
1083 #define verify_oop_msg(reg, msg) _verify_oop_checked(reg, "broken oop " #reg ", " #msg, __FILE__, __LINE__)
1084 #define verify_oop_addr(addr) _verify_oop_addr_checked(addr, "broken oop addr " #addr, __FILE__, __LINE__)
1085 #define verify_method_ptr(reg) _verify_method_ptr(reg, "broken method " #reg, __FILE__, __LINE__)
1086 #define verify_klass_ptr(reg) _verify_klass_ptr(reg, "broken klass " #reg, __FILE__, __LINE__)
1087 
1088   // Restore cpu control state after JNI call
1089   void restore_cpu_control_state_after_jni(Register tmp1, Register tmp2);
1090 
1091   // prints msg, dumps registers and stops execution
1092   void stop(const char* msg);
1093 
1094   static void debug64(char* msg, int64_t pc, int64_t regs[]);
1095 
1096   void untested()                                { stop("untested"); }
1097 
1098   void unimplemented(const char* what = "");
1099 
1100   void should_not_reach_here()                   { stop("should not reach here"); }
1101 
1102   void _assert_asm(Condition cc, const char* msg);
1103 #define assert_asm0(cc, msg) _assert_asm(cc, FILE_AND_LINE ": " msg)
1104 #define assert_asm(masm, command, cc, msg) DEBUG_ONLY(command; (masm)->_assert_asm(cc, FILE_AND_LINE ": " #command " " #cc ": " msg))
1105 
1106   // Stack overflow checking
1107   void bang_stack_with_offset(int offset) {
1108     // stack grows down, caller passes positive offset
1109     assert(offset > 0, "must bang with negative offset");
1110     sub(rscratch2, sp, offset);
1111     str(zr, Address(rscratch2));
1112   }
1113 
1114   // Writes to stack successive pages until offset reached to check for
1115   // stack overflow + shadow pages.  Also, clobbers tmp
1116   void bang_stack_size(Register size, Register tmp);
1117 
1118   // Check for reserved stack access in method being exited (for JIT)
1119   void reserved_stack_check();
1120 
1121   // Arithmetics
1122 
1123   void addptr(const Address &dst, int32_t src);
1124   void cmpptr(Register src1, Address src2);
1125 
1126   void cmpoop(Register obj1, Register obj2);
1127 
1128   // Various forms of CAS
1129 
1130   void cmpxchg_obj_header(Register oldv, Register newv, Register obj, Register tmp,
1131                           Label &succeed, Label *fail);
1132   void cmpxchgptr(Register oldv, Register newv, Register addr, Register tmp,
1133                   Label &succeed, Label *fail);
1134 
1135   void cmpxchgw(Register oldv, Register newv, Register addr, Register tmp,
1136                   Label &succeed, Label *fail);
1137 
1138   void atomic_add(Register prev, RegisterOrConstant incr, Register addr);
1139   void atomic_addw(Register prev, RegisterOrConstant incr, Register addr);
1140   void atomic_addal(Register prev, RegisterOrConstant incr, Register addr);
1141   void atomic_addalw(Register prev, RegisterOrConstant incr, Register addr);
1142 
1143   void atomic_xchg(Register prev, Register newv, Register addr);
1144   void atomic_xchgw(Register prev, Register newv, Register addr);
1145   void atomic_xchgl(Register prev, Register newv, Register addr);
1146   void atomic_xchglw(Register prev, Register newv, Register addr);
1147   void atomic_xchgal(Register prev, Register newv, Register addr);
1148   void atomic_xchgalw(Register prev, Register newv, Register addr);
1149 
1150   void orptr(Address adr, RegisterOrConstant src) {
1151     ldr(rscratch1, adr);
1152     if (src.is_register())
1153       orr(rscratch1, rscratch1, src.as_register());
1154     else
1155       orr(rscratch1, rscratch1, src.as_constant());
1156     str(rscratch1, adr);
1157   }
1158 
1159   // A generic CAS; success or failure is in the EQ flag.
1160   // Clobbers rscratch1
1161   void cmpxchg(Register addr, Register expected, Register new_val,
1162                enum operand_size size,
1163                bool acquire, bool release, bool weak,
1164                Register result);
1165 
1166 #ifdef ASSERT
1167   // Template short-hand support to clean-up after a failed call to trampoline
1168   // call generation (see trampoline_call() below),  when a set of Labels must
1169   // be reset (before returning).
1170   template<typename Label, typename... More>
1171   void reset_labels(Label &lbl, More&... more) {
1172     lbl.reset(); reset_labels(more...);
1173   }
1174   template<typename Label>
1175   void reset_labels(Label &lbl) {
1176     lbl.reset();
1177   }
1178 #endif
1179 
1180 private:
1181   void compare_eq(Register rn, Register rm, enum operand_size size);
1182 
1183 public:
1184   // AArch64 OpenJDK uses four different types of calls:
1185   //   - direct call: bl pc_relative_offset
1186   //     This is the shortest and the fastest, but the offset has the range:
1187   //     +/-128MB for the release build, +/-2MB for the debug build.
1188   //
1189   //   - far call: adrp reg, pc_relative_offset; add; bl reg
1190   //     This is longer than a direct call. The offset has
1191   //     the range +/-4GB. As the code cache size is limited to 4GB,
1192   //     far calls can reach anywhere in the code cache. If a jump is
1193   //     needed rather than a call, a far jump 'b reg' can be used instead.
1194   //     All instructions are embedded at a call site.
1195   //
1196   //   - trampoline call:
1197   //     This is only available in C1/C2-generated code (nmethod). It is a combination
1198   //     of a direct call, which is used if the destination of a call is in range,
1199   //     and a register-indirect call. It has the advantages of reaching anywhere in
1200   //     the AArch64 address space and being patchable at runtime when the generated
1201   //     code is being executed by other threads.
1202   //
1203   //     [Main code section]
1204   //       bl trampoline
1205   //     [Stub code section]
1206   //     trampoline:
1207   //       ldr reg, pc + 8
1208   //       br reg
1209   //       <64-bit destination address>
1210   //
1211   //     If the destination is in range when the generated code is moved to the code
1212   //     cache, 'bl trampoline' is replaced with 'bl destination' and the trampoline
1213   //     is not used.
1214   //     The optimization does not remove the trampoline from the stub section.
1215   //     This is necessary because the trampoline may well be redirected later when
1216   //     code is patched, and the new destination may not be reachable by a simple BR
1217   //     instruction.
1218   //
1219   //   - indirect call: move reg, address; blr reg
1220   //     This too can reach anywhere in the address space, but it cannot be
1221   //     patched while code is running, so it must only be modified at a safepoint.
1222   //     This form of call is most suitable for targets at fixed addresses, which
1223   //     will never be patched.
1224   //
1225   // The patching we do conforms to the "Concurrent modification and
1226   // execution of instructions" section of the Arm Architectural
1227   // Reference Manual, which only allows B, BL, BRK, HVC, ISB, NOP, SMC,
1228   // or SVC instructions to be modified while another thread is
1229   // executing them.
1230   //
1231   // To patch a trampoline call when the BL can't reach, we first modify
1232   // the 64-bit destination address in the trampoline, then modify the
1233   // BL to point to the trampoline, then flush the instruction cache to
1234   // broadcast the change to all executing threads. See
1235   // NativeCall::set_destination_mt_safe for the details.
1236   //
1237   // There is a benign race in that the other thread might observe the
1238   // modified BL before it observes the modified 64-bit destination
1239   // address. That does not matter because the destination method has been
1240   // invalidated, so there will be a trap at its start.
1241   // For this to work, the destination address in the trampoline is
1242   // always updated, even if we're not using the trampoline.
1243 
1244   // Emit a direct call if the entry address will always be in range,
1245   // otherwise a trampoline call.
1246   // Supported entry.rspec():
1247   // - relocInfo::runtime_call_type
1248   // - relocInfo::opt_virtual_call_type
1249   // - relocInfo::static_call_type
1250   // - relocInfo::virtual_call_type
1251   //
1252   // Return: the call PC or null if CodeCache is full.
1253   // Clobbers: rscratch1
1254   address trampoline_call(Address entry);
1255 
1256   static bool far_branches() {
1257     return ReservedCodeCacheSize > branch_range;
1258   }
1259 
1260   // Check if branches to the non nmethod section require a far jump
1261   static bool codestub_branch_needs_far_jump() {
1262     if (SCCache::is_on_for_write()) {
1263       // To calculate far_codestub_branch_size correctly.
1264       return true;
1265     }
1266     return CodeCache::max_distance_to_non_nmethod() > branch_range;
1267   }
1268 
1269   // Emit a direct call/jump if the entry address will always be in range,
1270   // otherwise a far call/jump.
1271   // The address must be inside the code cache.
1272   // Supported entry.rspec():
1273   // - relocInfo::external_word_type
1274   // - relocInfo::runtime_call_type
1275   // - relocInfo::none
1276   // In the case of a far call/jump, the entry address is put in the tmp register.
1277   // The tmp register is invalidated.
1278   //
1279   // Far_jump returns the amount of the emitted code.
1280   void far_call(Address entry, Register tmp = rscratch1);
1281   int far_jump(Address entry, Register tmp = rscratch1);
1282 
1283   static int far_codestub_branch_size() {
1284     if (codestub_branch_needs_far_jump()) {
1285       return 3 * 4;  // adrp, add, br
1286     } else {
1287       return 4;
1288     }
1289   }
1290 
1291   // Emit the CompiledIC call idiom
1292   address ic_call(address entry, jint method_index = 0);
1293   static int ic_check_size();
1294   int ic_check(int end_alignment);
1295 
1296 public:
1297 
1298   // Data
1299 
1300   void mov_metadata(Register dst, Metadata* obj);
1301   Address allocate_metadata_address(Metadata* obj);
1302   Address constant_oop_address(jobject obj);
1303 
1304   void movoop(Register dst, jobject obj);
1305 
1306   // CRC32 code for java.util.zip.CRC32::updateBytes() intrinsic.
1307   void kernel_crc32(Register crc, Register buf, Register len,
1308         Register table0, Register table1, Register table2, Register table3,
1309         Register tmp, Register tmp2, Register tmp3);
1310   // CRC32 code for java.util.zip.CRC32C::updateBytes() intrinsic.
1311   void kernel_crc32c(Register crc, Register buf, Register len,
1312         Register table0, Register table1, Register table2, Register table3,
1313         Register tmp, Register tmp2, Register tmp3);
1314 
1315   // Stack push and pop individual 64 bit registers
1316   void push(Register src);
1317   void pop(Register dst);
1318 
1319   void repne_scan(Register addr, Register value, Register count,
1320                   Register scratch);
1321   void repne_scanw(Register addr, Register value, Register count,
1322                    Register scratch);
1323 
1324   typedef void (MacroAssembler::* add_sub_imm_insn)(Register Rd, Register Rn, unsigned imm);
1325   typedef void (MacroAssembler::* add_sub_reg_insn)(Register Rd, Register Rn, Register Rm, enum shift_kind kind, unsigned shift);
1326 
1327   // If a constant does not fit in an immediate field, generate some
1328   // number of MOV instructions and then perform the operation
1329   void wrap_add_sub_imm_insn(Register Rd, Register Rn, uint64_t imm,
1330                              add_sub_imm_insn insn1,
1331                              add_sub_reg_insn insn2, bool is32);
1332   // Separate vsn which sets the flags
1333   void wrap_adds_subs_imm_insn(Register Rd, Register Rn, uint64_t imm,
1334                                add_sub_imm_insn insn1,
1335                                add_sub_reg_insn insn2, bool is32);
1336 
1337 #define WRAP(INSN, is32)                                                \
1338   void INSN(Register Rd, Register Rn, uint64_t imm) {                   \
1339     wrap_add_sub_imm_insn(Rd, Rn, imm, &Assembler::INSN, &Assembler::INSN, is32); \
1340   }                                                                     \
1341                                                                         \
1342   void INSN(Register Rd, Register Rn, Register Rm,                      \
1343              enum shift_kind kind, unsigned shift = 0) {                \
1344     Assembler::INSN(Rd, Rn, Rm, kind, shift);                           \
1345   }                                                                     \
1346                                                                         \
1347   void INSN(Register Rd, Register Rn, Register Rm) {                    \
1348     Assembler::INSN(Rd, Rn, Rm);                                        \
1349   }                                                                     \
1350                                                                         \
1351   void INSN(Register Rd, Register Rn, Register Rm,                      \
1352            ext::operation option, int amount = 0) {                     \
1353     Assembler::INSN(Rd, Rn, Rm, option, amount);                        \
1354   }
1355 
1356   WRAP(add, false) WRAP(addw, true) WRAP(sub, false) WRAP(subw, true)
1357 
1358 #undef WRAP
1359 #define WRAP(INSN, is32)                                                \
1360   void INSN(Register Rd, Register Rn, uint64_t imm) {                   \
1361     wrap_adds_subs_imm_insn(Rd, Rn, imm, &Assembler::INSN, &Assembler::INSN, is32); \
1362   }                                                                     \
1363                                                                         \
1364   void INSN(Register Rd, Register Rn, Register Rm,                      \
1365              enum shift_kind kind, unsigned shift = 0) {                \
1366     Assembler::INSN(Rd, Rn, Rm, kind, shift);                           \
1367   }                                                                     \
1368                                                                         \
1369   void INSN(Register Rd, Register Rn, Register Rm) {                    \
1370     Assembler::INSN(Rd, Rn, Rm);                                        \
1371   }                                                                     \
1372                                                                         \
1373   void INSN(Register Rd, Register Rn, Register Rm,                      \
1374            ext::operation option, int amount = 0) {                     \
1375     Assembler::INSN(Rd, Rn, Rm, option, amount);                        \
1376   }
1377 
1378   WRAP(adds, false) WRAP(addsw, true) WRAP(subs, false) WRAP(subsw, true)
1379 
1380   void add(Register Rd, Register Rn, RegisterOrConstant increment);
1381   void addw(Register Rd, Register Rn, RegisterOrConstant increment);
1382   void sub(Register Rd, Register Rn, RegisterOrConstant decrement);
1383   void subw(Register Rd, Register Rn, RegisterOrConstant decrement);
1384 
1385   void adrp(Register reg1, const Address &dest, uint64_t &byte_offset);
1386 
1387   void tableswitch(Register index, jint lowbound, jint highbound,
1388                    Label &jumptable, Label &jumptable_end, int stride = 1) {
1389     adr(rscratch1, jumptable);
1390     subsw(rscratch2, index, lowbound);
1391     subsw(zr, rscratch2, highbound - lowbound);
1392     br(Assembler::HS, jumptable_end);
1393     add(rscratch1, rscratch1, rscratch2,
1394         ext::sxtw, exact_log2(stride * Assembler::instruction_size));
1395     br(rscratch1);
1396   }
1397 
1398   // Form an address from base + offset in Rd.  Rd may or may not
1399   // actually be used: you must use the Address that is returned.  It
1400   // is up to you to ensure that the shift provided matches the size
1401   // of your data.
1402   Address form_address(Register Rd, Register base, int64_t byte_offset, int shift);
1403 
1404   // Return true iff an address is within the 48-bit AArch64 address
1405   // space.
1406   bool is_valid_AArch64_address(address a) {
1407     return ((uint64_t)a >> 48) == 0;
1408   }
1409 
1410   // Load the base of the cardtable byte map into reg.
1411   void load_byte_map_base(Register reg);
1412 
1413   // Load a constant address in the AOT Runtime Constants area
1414   void load_aotrc_address(Register reg, address a);
1415 
1416   // Prolog generator routines to support switch between x86 code and
1417   // generated ARM code
1418 
1419   // routine to generate an x86 prolog for a stub function which
1420   // bootstraps into the generated ARM code which directly follows the
1421   // stub
1422   //
1423 
1424   public:
1425 
1426   void ldr_constant(Register dest, const Address &const_addr) {
1427     if (NearCpool) {
1428       ldr(dest, const_addr);
1429     } else {
1430       uint64_t offset;
1431       adrp(dest, InternalAddress(const_addr.target()), offset);
1432       ldr(dest, Address(dest, offset));
1433     }
1434   }
1435 
1436   address read_polling_page(Register r, relocInfo::relocType rtype);
1437   void get_polling_page(Register dest, relocInfo::relocType rtype);
1438 
1439   // CRC32 code for java.util.zip.CRC32::updateBytes() intrinsic.
1440   void update_byte_crc32(Register crc, Register val, Register table);
1441   void update_word_crc32(Register crc, Register v, Register tmp,
1442         Register table0, Register table1, Register table2, Register table3,
1443         bool upper = false);
1444 
1445   address count_positives(Register ary1, Register len, Register result);
1446 
1447   address arrays_equals(Register a1, Register a2, Register result, Register cnt1,
1448                         Register tmp1, Register tmp2, Register tmp3, int elem_size);
1449 
1450   void string_equals(Register a1, Register a2, Register result, Register cnt1);
1451 
1452   void fill_words(Register base, Register cnt, Register value);
1453   address zero_words(Register base, uint64_t cnt);
1454   address zero_words(Register ptr, Register cnt);
1455   void zero_dcache_blocks(Register base, Register cnt);
1456 
1457   static const int zero_words_block_size;
1458 
1459   address byte_array_inflate(Register src, Register dst, Register len,
1460                              FloatRegister vtmp1, FloatRegister vtmp2,
1461                              FloatRegister vtmp3, Register tmp4);
1462 
1463   void char_array_compress(Register src, Register dst, Register len,
1464                            Register res,
1465                            FloatRegister vtmp0, FloatRegister vtmp1,
1466                            FloatRegister vtmp2, FloatRegister vtmp3,
1467                            FloatRegister vtmp4, FloatRegister vtmp5);
1468 
1469   void encode_iso_array(Register src, Register dst,
1470                         Register len, Register res, bool ascii,
1471                         FloatRegister vtmp0, FloatRegister vtmp1,
1472                         FloatRegister vtmp2, FloatRegister vtmp3,
1473                         FloatRegister vtmp4, FloatRegister vtmp5);
1474 
1475   void generate_dsin_dcos(bool isCos, address npio2_hw, address two_over_pi,
1476       address pio2, address dsin_coef, address dcos_coef);
1477  private:
1478   // begin trigonometric functions support block
1479   void generate__ieee754_rem_pio2(address npio2_hw, address two_over_pi, address pio2);
1480   void generate__kernel_rem_pio2(address two_over_pi, address pio2);
1481   void generate_kernel_sin(FloatRegister x, bool iyIsOne, address dsin_coef);
1482   void generate_kernel_cos(FloatRegister x, address dcos_coef);
1483   // end trigonometric functions support block
1484   void add2_with_carry(Register final_dest_hi, Register dest_hi, Register dest_lo,
1485                        Register src1, Register src2);
1486   void add2_with_carry(Register dest_hi, Register dest_lo, Register src1, Register src2) {
1487     add2_with_carry(dest_hi, dest_hi, dest_lo, src1, src2);
1488   }
1489   void multiply_64_x_64_loop(Register x, Register xstart, Register x_xstart,
1490                              Register y, Register y_idx, Register z,
1491                              Register carry, Register product,
1492                              Register idx, Register kdx);
1493   void multiply_128_x_128_loop(Register y, Register z,
1494                                Register carry, Register carry2,
1495                                Register idx, Register jdx,
1496                                Register yz_idx1, Register yz_idx2,
1497                                Register tmp, Register tmp3, Register tmp4,
1498                                Register tmp7, Register product_hi);
1499   void kernel_crc32_using_crypto_pmull(Register crc, Register buf,
1500         Register len, Register tmp0, Register tmp1, Register tmp2,
1501         Register tmp3);
1502   void kernel_crc32_using_crc32(Register crc, Register buf,
1503         Register len, Register tmp0, Register tmp1, Register tmp2,
1504         Register tmp3);
1505   void kernel_crc32c_using_crypto_pmull(Register crc, Register buf,
1506         Register len, Register tmp0, Register tmp1, Register tmp2,
1507         Register tmp3);
1508   void kernel_crc32c_using_crc32c(Register crc, Register buf,
1509         Register len, Register tmp0, Register tmp1, Register tmp2,
1510         Register tmp3);
1511   void kernel_crc32_common_fold_using_crypto_pmull(Register crc, Register buf,
1512         Register len, Register tmp0, Register tmp1, Register tmp2,
1513         size_t table_offset);
1514 
1515   void ghash_modmul (FloatRegister result,
1516                      FloatRegister result_lo, FloatRegister result_hi, FloatRegister b,
1517                      FloatRegister a, FloatRegister vzr, FloatRegister a1_xor_a0, FloatRegister p,
1518                      FloatRegister t1, FloatRegister t2, FloatRegister t3);
1519   void ghash_load_wide(int index, Register data, FloatRegister result, FloatRegister state);
1520 public:
1521   void multiply_to_len(Register x, Register xlen, Register y, Register ylen, Register z,
1522                        Register tmp0, Register tmp1, Register tmp2, Register tmp3,
1523                        Register tmp4, Register tmp5, Register tmp6, Register tmp7);
1524   void mul_add(Register out, Register in, Register offs, Register len, Register k);
1525   void ghash_multiply(FloatRegister result_lo, FloatRegister result_hi,
1526                       FloatRegister a, FloatRegister b, FloatRegister a1_xor_a0,
1527                       FloatRegister tmp1, FloatRegister tmp2, FloatRegister tmp3);
1528   void ghash_multiply_wide(int index,
1529                            FloatRegister result_lo, FloatRegister result_hi,
1530                            FloatRegister a, FloatRegister b, FloatRegister a1_xor_a0,
1531                            FloatRegister tmp1, FloatRegister tmp2, FloatRegister tmp3);
1532   void ghash_reduce(FloatRegister result, FloatRegister lo, FloatRegister hi,
1533                     FloatRegister p, FloatRegister z, FloatRegister t1);
1534   void ghash_reduce_wide(int index, FloatRegister result, FloatRegister lo, FloatRegister hi,
1535                     FloatRegister p, FloatRegister z, FloatRegister t1);
1536   void ghash_processBlocks_wide(address p, Register state, Register subkeyH,
1537                                 Register data, Register blocks, int unrolls);
1538 
1539 
1540   void aesenc_loadkeys(Register key, Register keylen);
1541   void aesecb_encrypt(Register from, Register to, Register keylen,
1542                       FloatRegister data = v0, int unrolls = 1);
1543   void aesecb_decrypt(Register from, Register to, Register key, Register keylen);
1544   void aes_round(FloatRegister input, FloatRegister subkey);
1545 
1546   // ChaCha20 functions support block
1547   void cc20_quarter_round(FloatRegister aVec, FloatRegister bVec,
1548           FloatRegister cVec, FloatRegister dVec, FloatRegister scratch,
1549           FloatRegister tbl);
1550   void cc20_shift_lane_org(FloatRegister bVec, FloatRegister cVec,
1551           FloatRegister dVec, bool colToDiag);
1552 
1553   // Place an ISB after code may have been modified due to a safepoint.
1554   void safepoint_isb();
1555 
1556 private:
1557   // Return the effective address r + (r1 << ext) + offset.
1558   // Uses rscratch2.
1559   Address offsetted_address(Register r, Register r1, Address::extend ext,
1560                             int offset, int size);
1561 
1562 private:
1563   // Returns an address on the stack which is reachable with a ldr/str of size
1564   // Uses rscratch2 if the address is not directly reachable
1565   Address spill_address(int size, int offset, Register tmp=rscratch2);
1566   Address sve_spill_address(int sve_reg_size_in_bytes, int offset, Register tmp=rscratch2);
1567 
1568   bool merge_alignment_check(Register base, size_t size, int64_t cur_offset, int64_t prev_offset) const;
1569 
1570   // Check whether two loads/stores can be merged into ldp/stp.
1571   bool ldst_can_merge(Register rx, const Address &adr, size_t cur_size_in_bytes, bool is_store) const;
1572 
1573   // Merge current load/store with previous load/store into ldp/stp.
1574   void merge_ldst(Register rx, const Address &adr, size_t cur_size_in_bytes, bool is_store);
1575 
1576   // Try to merge two loads/stores into ldp/stp. If success, returns true else false.
1577   bool try_merge_ldst(Register rt, const Address &adr, size_t cur_size_in_bytes, bool is_store);
1578 
1579 public:
1580   void spill(Register Rx, bool is64, int offset) {
1581     if (is64) {
1582       str(Rx, spill_address(8, offset));
1583     } else {
1584       strw(Rx, spill_address(4, offset));
1585     }
1586   }
1587   void spill(FloatRegister Vx, SIMD_RegVariant T, int offset) {
1588     str(Vx, T, spill_address(1 << (int)T, offset));
1589   }
1590 
1591   void spill_sve_vector(FloatRegister Zx, int offset, int vector_reg_size_in_bytes) {
1592     sve_str(Zx, sve_spill_address(vector_reg_size_in_bytes, offset));
1593   }
1594   void spill_sve_predicate(PRegister pr, int offset, int predicate_reg_size_in_bytes) {
1595     sve_str(pr, sve_spill_address(predicate_reg_size_in_bytes, offset));
1596   }
1597 
1598   void unspill(Register Rx, bool is64, int offset) {
1599     if (is64) {
1600       ldr(Rx, spill_address(8, offset));
1601     } else {
1602       ldrw(Rx, spill_address(4, offset));
1603     }
1604   }
1605   void unspill(FloatRegister Vx, SIMD_RegVariant T, int offset) {
1606     ldr(Vx, T, spill_address(1 << (int)T, offset));
1607   }
1608 
1609   void unspill_sve_vector(FloatRegister Zx, int offset, int vector_reg_size_in_bytes) {
1610     sve_ldr(Zx, sve_spill_address(vector_reg_size_in_bytes, offset));
1611   }
1612   void unspill_sve_predicate(PRegister pr, int offset, int predicate_reg_size_in_bytes) {
1613     sve_ldr(pr, sve_spill_address(predicate_reg_size_in_bytes, offset));
1614   }
1615 
1616   void spill_copy128(int src_offset, int dst_offset,
1617                      Register tmp1=rscratch1, Register tmp2=rscratch2) {
1618     if (src_offset < 512 && (src_offset & 7) == 0 &&
1619         dst_offset < 512 && (dst_offset & 7) == 0) {
1620       ldp(tmp1, tmp2, Address(sp, src_offset));
1621       stp(tmp1, tmp2, Address(sp, dst_offset));
1622     } else {
1623       unspill(tmp1, true, src_offset);
1624       spill(tmp1, true, dst_offset);
1625       unspill(tmp1, true, src_offset+8);
1626       spill(tmp1, true, dst_offset+8);
1627     }
1628   }
1629   void spill_copy_sve_vector_stack_to_stack(int src_offset, int dst_offset,
1630                                             int sve_vec_reg_size_in_bytes) {
1631     assert(sve_vec_reg_size_in_bytes % 16 == 0, "unexpected sve vector reg size");
1632     for (int i = 0; i < sve_vec_reg_size_in_bytes / 16; i++) {
1633       spill_copy128(src_offset, dst_offset);
1634       src_offset += 16;
1635       dst_offset += 16;
1636     }
1637   }
1638   void spill_copy_sve_predicate_stack_to_stack(int src_offset, int dst_offset,
1639                                                int sve_predicate_reg_size_in_bytes) {
1640     sve_ldr(ptrue, sve_spill_address(sve_predicate_reg_size_in_bytes, src_offset));
1641     sve_str(ptrue, sve_spill_address(sve_predicate_reg_size_in_bytes, dst_offset));
1642     reinitialize_ptrue();
1643   }
1644   void cache_wb(Address line);
1645   void cache_wbsync(bool is_pre);
1646 
1647   // Code for java.lang.Thread::onSpinWait() intrinsic.
1648   void spin_wait();
1649 
1650   void lightweight_lock(Register basic_lock, Register obj, Register t1, Register t2, Register t3, Label& slow);
1651   void lightweight_unlock(Register obj, Register t1, Register t2, Register t3, Label& slow);
1652 
1653 private:
1654   // Check the current thread doesn't need a cross modify fence.
1655   void verify_cross_modify_fence_not_required() PRODUCT_RETURN;
1656 
1657 };
1658 
1659 #ifdef ASSERT
1660 inline bool AbstractAssembler::pd_check_instruction_mark() { return false; }
1661 #endif
1662 
1663 /**
1664  * class SkipIfEqual:
1665  *
1666  * Instantiating this class will result in assembly code being output that will
1667  * jump around any code emitted between the creation of the instance and it's
1668  * automatic destruction at the end of a scope block, depending on the value of
1669  * the flag passed to the constructor, which will be checked at run-time.
1670  */
1671 class SkipIfEqual {
1672  private:
1673   MacroAssembler* _masm;
1674   Label _label;
1675 
1676  public:
1677    SkipIfEqual(MacroAssembler*, const bool* flag_addr, bool value);
1678    ~SkipIfEqual();
1679 };
1680 
1681 struct tableswitch {
1682   Register _reg;
1683   int _insn_index; jint _first_key; jint _last_key;
1684   Label _after;
1685   Label _branches;
1686 };
1687 
1688 #endif // CPU_AARCH64_MACROASSEMBLER_AARCH64_HPP