1 /*
   2  * Copyright (c) 1997, 2018, Oracle and/or its affiliates. All rights reserved.
   3  * Copyright (c) 2014, 2015, 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 #include <sys/types.h>
  27 
  28 #include "precompiled.hpp"
  29 #include "jvm.h"
  30 #include "asm/assembler.hpp"
  31 #include "asm/assembler.inline.hpp"
  32 #include "gc/shared/barrierSet.hpp"
  33 #include "gc/shared/cardTable.hpp"
  34 #include "gc/shared/barrierSetAssembler.hpp"
  35 #include "gc/shared/cardTableBarrierSet.hpp"
  36 #include "interpreter/interpreter.hpp"
  37 #include "compiler/disassembler.hpp"
  38 #include "memory/resourceArea.hpp"
  39 #include "nativeInst_aarch64.hpp"
  40 #include "oops/accessDecorators.hpp"
  41 #include "oops/compressedOops.inline.hpp"
  42 #include "oops/klass.inline.hpp"
  43 #include "oops/oop.hpp"
  44 #include "opto/compile.hpp"
  45 #include "opto/intrinsicnode.hpp"
  46 #include "opto/node.hpp"
  47 #include "runtime/biasedLocking.hpp"
  48 #include "runtime/icache.hpp"
  49 #include "runtime/interfaceSupport.inline.hpp"
  50 #include "runtime/jniHandles.inline.hpp"
  51 #include "runtime/sharedRuntime.hpp"
  52 #include "runtime/thread.hpp"
  53 
  54 #ifdef PRODUCT
  55 #define BLOCK_COMMENT(str) /* nothing */
  56 #define STOP(error) stop(error)
  57 #else
  58 #define BLOCK_COMMENT(str) block_comment(str)
  59 #define STOP(error) block_comment(error); stop(error)
  60 #endif
  61 
  62 #define BIND(label) bind(label); BLOCK_COMMENT(#label ":")
  63 
  64 // Patch any kind of instruction; there may be several instructions.
  65 // Return the total length (in bytes) of the instructions.
  66 int MacroAssembler::pd_patch_instruction_size(address branch, address target) {
  67   int instructions = 1;
  68   assert((uint64_t)target < (1ul << 48), "48-bit overflow in address constant");
  69   long offset = (target - branch) >> 2;
  70   unsigned insn = *(unsigned*)branch;
  71   if ((Instruction_aarch64::extract(insn, 29, 24) & 0b111011) == 0b011000) {
  72     // Load register (literal)
  73     Instruction_aarch64::spatch(branch, 23, 5, offset);
  74   } else if (Instruction_aarch64::extract(insn, 30, 26) == 0b00101) {
  75     // Unconditional branch (immediate)
  76     Instruction_aarch64::spatch(branch, 25, 0, offset);
  77   } else if (Instruction_aarch64::extract(insn, 31, 25) == 0b0101010) {
  78     // Conditional branch (immediate)
  79     Instruction_aarch64::spatch(branch, 23, 5, offset);
  80   } else if (Instruction_aarch64::extract(insn, 30, 25) == 0b011010) {
  81     // Compare & branch (immediate)
  82     Instruction_aarch64::spatch(branch, 23, 5, offset);
  83   } else if (Instruction_aarch64::extract(insn, 30, 25) == 0b011011) {
  84     // Test & branch (immediate)
  85     Instruction_aarch64::spatch(branch, 18, 5, offset);
  86   } else if (Instruction_aarch64::extract(insn, 28, 24) == 0b10000) {
  87     // PC-rel. addressing
  88     offset = target-branch;
  89     int shift = Instruction_aarch64::extract(insn, 31, 31);
  90     if (shift) {
  91       u_int64_t dest = (u_int64_t)target;
  92       uint64_t pc_page = (uint64_t)branch >> 12;
  93       uint64_t adr_page = (uint64_t)target >> 12;
  94       unsigned offset_lo = dest & 0xfff;
  95       offset = adr_page - pc_page;
  96 
  97       // We handle 4 types of PC relative addressing
  98       //   1 - adrp    Rx, target_page
  99       //       ldr/str Ry, [Rx, #offset_in_page]
 100       //   2 - adrp    Rx, target_page
 101       //       add     Ry, Rx, #offset_in_page
 102       //   3 - adrp    Rx, target_page (page aligned reloc, offset == 0)
 103       //       movk    Rx, #imm16<<32
 104       //   4 - adrp    Rx, target_page (page aligned reloc, offset == 0)
 105       // In the first 3 cases we must check that Rx is the same in the adrp and the
 106       // subsequent ldr/str, add or movk instruction. Otherwise we could accidentally end
 107       // up treating a type 4 relocation as a type 1, 2 or 3 just because it happened
 108       // to be followed by a random unrelated ldr/str, add or movk instruction.
 109       //
 110       unsigned insn2 = ((unsigned*)branch)[1];
 111       if (Instruction_aarch64::extract(insn2, 29, 24) == 0b111001 &&
 112                 Instruction_aarch64::extract(insn, 4, 0) ==
 113                         Instruction_aarch64::extract(insn2, 9, 5)) {
 114         // Load/store register (unsigned immediate)
 115         unsigned size = Instruction_aarch64::extract(insn2, 31, 30);
 116         Instruction_aarch64::patch(branch + sizeof (unsigned),
 117                                     21, 10, offset_lo >> size);
 118         guarantee(((dest >> size) << size) == dest, "misaligned target");
 119         instructions = 2;
 120       } else if (Instruction_aarch64::extract(insn2, 31, 22) == 0b1001000100 &&
 121                 Instruction_aarch64::extract(insn, 4, 0) ==
 122                         Instruction_aarch64::extract(insn2, 4, 0)) {
 123         // add (immediate)
 124         Instruction_aarch64::patch(branch + sizeof (unsigned),
 125                                    21, 10, offset_lo);
 126         instructions = 2;
 127       } else if (Instruction_aarch64::extract(insn2, 31, 21) == 0b11110010110 &&
 128                    Instruction_aarch64::extract(insn, 4, 0) ==
 129                      Instruction_aarch64::extract(insn2, 4, 0)) {
 130         // movk #imm16<<32
 131         Instruction_aarch64::patch(branch + 4, 20, 5, (uint64_t)target >> 32);
 132         long dest = ((long)target & 0xffffffffL) | ((long)branch & 0xffff00000000L);
 133         long pc_page = (long)branch >> 12;
 134         long adr_page = (long)dest >> 12;
 135         offset = adr_page - pc_page;
 136         instructions = 2;
 137       }
 138     }
 139     int offset_lo = offset & 3;
 140     offset >>= 2;
 141     Instruction_aarch64::spatch(branch, 23, 5, offset);
 142     Instruction_aarch64::patch(branch, 30, 29, offset_lo);
 143   } else if (Instruction_aarch64::extract(insn, 31, 21) == 0b11010010100) {
 144     u_int64_t dest = (u_int64_t)target;
 145     // Move wide constant
 146     assert(nativeInstruction_at(branch+4)->is_movk(), "wrong insns in patch");
 147     assert(nativeInstruction_at(branch+8)->is_movk(), "wrong insns in patch");
 148     Instruction_aarch64::patch(branch, 20, 5, dest & 0xffff);
 149     Instruction_aarch64::patch(branch+4, 20, 5, (dest >>= 16) & 0xffff);
 150     Instruction_aarch64::patch(branch+8, 20, 5, (dest >>= 16) & 0xffff);
 151     assert(target_addr_for_insn(branch) == target, "should be");
 152     instructions = 3;
 153   } else if (Instruction_aarch64::extract(insn, 31, 22) == 0b1011100101 &&
 154              Instruction_aarch64::extract(insn, 4, 0) == 0b11111) {
 155     // nothing to do
 156     assert(target == 0, "did not expect to relocate target for polling page load");
 157   } else {
 158     ShouldNotReachHere();
 159   }
 160   return instructions * NativeInstruction::instruction_size;
 161 }
 162 
 163 int MacroAssembler::patch_oop(address insn_addr, address o) {
 164   int instructions;
 165   unsigned insn = *(unsigned*)insn_addr;
 166   assert(nativeInstruction_at(insn_addr+4)->is_movk(), "wrong insns in patch");
 167 
 168   // OOPs are either narrow (32 bits) or wide (48 bits).  We encode
 169   // narrow OOPs by setting the upper 16 bits in the first
 170   // instruction.
 171   if (Instruction_aarch64::extract(insn, 31, 21) == 0b11010010101) {
 172     // Move narrow OOP
 173     narrowOop n = CompressedOops::encode((oop)o);
 174     Instruction_aarch64::patch(insn_addr, 20, 5, n >> 16);
 175     Instruction_aarch64::patch(insn_addr+4, 20, 5, n & 0xffff);
 176     instructions = 2;
 177   } else {
 178     // Move wide OOP
 179     assert(nativeInstruction_at(insn_addr+8)->is_movk(), "wrong insns in patch");
 180     uintptr_t dest = (uintptr_t)o;
 181     Instruction_aarch64::patch(insn_addr, 20, 5, dest & 0xffff);
 182     Instruction_aarch64::patch(insn_addr+4, 20, 5, (dest >>= 16) & 0xffff);
 183     Instruction_aarch64::patch(insn_addr+8, 20, 5, (dest >>= 16) & 0xffff);
 184     instructions = 3;
 185   }
 186   return instructions * NativeInstruction::instruction_size;
 187 }
 188 
 189 int MacroAssembler::patch_narrow_klass(address insn_addr, narrowKlass n) {
 190   // Metatdata pointers are either narrow (32 bits) or wide (48 bits).
 191   // We encode narrow ones by setting the upper 16 bits in the first
 192   // instruction.
 193   NativeInstruction *insn = nativeInstruction_at(insn_addr);
 194   assert(Instruction_aarch64::extract(insn->encoding(), 31, 21) == 0b11010010101 &&
 195          nativeInstruction_at(insn_addr+4)->is_movk(), "wrong insns in patch");
 196 
 197   Instruction_aarch64::patch(insn_addr, 20, 5, n >> 16);
 198   Instruction_aarch64::patch(insn_addr+4, 20, 5, n & 0xffff);
 199   return 2 * NativeInstruction::instruction_size;
 200 }
 201 
 202 address MacroAssembler::target_addr_for_insn(address insn_addr, unsigned insn) {
 203   long offset = 0;
 204   if ((Instruction_aarch64::extract(insn, 29, 24) & 0b011011) == 0b00011000) {
 205     // Load register (literal)
 206     offset = Instruction_aarch64::sextract(insn, 23, 5);
 207     return address(((uint64_t)insn_addr + (offset << 2)));
 208   } else if (Instruction_aarch64::extract(insn, 30, 26) == 0b00101) {
 209     // Unconditional branch (immediate)
 210     offset = Instruction_aarch64::sextract(insn, 25, 0);
 211   } else if (Instruction_aarch64::extract(insn, 31, 25) == 0b0101010) {
 212     // Conditional branch (immediate)
 213     offset = Instruction_aarch64::sextract(insn, 23, 5);
 214   } else if (Instruction_aarch64::extract(insn, 30, 25) == 0b011010) {
 215     // Compare & branch (immediate)
 216     offset = Instruction_aarch64::sextract(insn, 23, 5);
 217    } else if (Instruction_aarch64::extract(insn, 30, 25) == 0b011011) {
 218     // Test & branch (immediate)
 219     offset = Instruction_aarch64::sextract(insn, 18, 5);
 220   } else if (Instruction_aarch64::extract(insn, 28, 24) == 0b10000) {
 221     // PC-rel. addressing
 222     offset = Instruction_aarch64::extract(insn, 30, 29);
 223     offset |= Instruction_aarch64::sextract(insn, 23, 5) << 2;
 224     int shift = Instruction_aarch64::extract(insn, 31, 31) ? 12 : 0;
 225     if (shift) {
 226       offset <<= shift;
 227       uint64_t target_page = ((uint64_t)insn_addr) + offset;
 228       target_page &= ((uint64_t)-1) << shift;
 229       // Return the target address for the following sequences
 230       //   1 - adrp    Rx, target_page
 231       //       ldr/str Ry, [Rx, #offset_in_page]
 232       //   2 - adrp    Rx, target_page
 233       //       add     Ry, Rx, #offset_in_page
 234       //   3 - adrp    Rx, target_page (page aligned reloc, offset == 0)
 235       //       movk    Rx, #imm12<<32
 236       //   4 - adrp    Rx, target_page (page aligned reloc, offset == 0)
 237       //
 238       // In the first two cases  we check that the register is the same and
 239       // return the target_page + the offset within the page.
 240       // Otherwise we assume it is a page aligned relocation and return
 241       // the target page only.
 242       //
 243       unsigned insn2 = ((unsigned*)insn_addr)[1];
 244       if (Instruction_aarch64::extract(insn2, 29, 24) == 0b111001 &&
 245                 Instruction_aarch64::extract(insn, 4, 0) ==
 246                         Instruction_aarch64::extract(insn2, 9, 5)) {
 247         // Load/store register (unsigned immediate)
 248         unsigned int byte_offset = Instruction_aarch64::extract(insn2, 21, 10);
 249         unsigned int size = Instruction_aarch64::extract(insn2, 31, 30);
 250         return address(target_page + (byte_offset << size));
 251       } else if (Instruction_aarch64::extract(insn2, 31, 22) == 0b1001000100 &&
 252                 Instruction_aarch64::extract(insn, 4, 0) ==
 253                         Instruction_aarch64::extract(insn2, 4, 0)) {
 254         // add (immediate)
 255         unsigned int byte_offset = Instruction_aarch64::extract(insn2, 21, 10);
 256         return address(target_page + byte_offset);
 257       } else {
 258         if (Instruction_aarch64::extract(insn2, 31, 21) == 0b11110010110  &&
 259                Instruction_aarch64::extract(insn, 4, 0) ==
 260                  Instruction_aarch64::extract(insn2, 4, 0)) {
 261           target_page = (target_page & 0xffffffff) |
 262                          ((uint64_t)Instruction_aarch64::extract(insn2, 20, 5) << 32);
 263         }
 264         return (address)target_page;
 265       }
 266     } else {
 267       ShouldNotReachHere();
 268     }
 269   } else if (Instruction_aarch64::extract(insn, 31, 23) == 0b110100101) {
 270     u_int32_t *insns = (u_int32_t *)insn_addr;
 271     // Move wide constant: movz, movk, movk.  See movptr().
 272     assert(nativeInstruction_at(insns+1)->is_movk(), "wrong insns in patch");
 273     assert(nativeInstruction_at(insns+2)->is_movk(), "wrong insns in patch");
 274     return address(u_int64_t(Instruction_aarch64::extract(insns[0], 20, 5))
 275                    + (u_int64_t(Instruction_aarch64::extract(insns[1], 20, 5)) << 16)
 276                    + (u_int64_t(Instruction_aarch64::extract(insns[2], 20, 5)) << 32));
 277   } else if (Instruction_aarch64::extract(insn, 31, 22) == 0b1011100101 &&
 278              Instruction_aarch64::extract(insn, 4, 0) == 0b11111) {
 279     return 0;
 280   } else {
 281     ShouldNotReachHere();
 282   }
 283   return address(((uint64_t)insn_addr + (offset << 2)));
 284 }
 285 
 286 void MacroAssembler::serialize_memory(Register thread, Register tmp) {
 287   dsb(Assembler::SY);
 288 }
 289 
 290 void MacroAssembler::safepoint_poll(Label& slow_path) {
 291   if (SafepointMechanism::uses_thread_local_poll()) {
 292     ldr(rscratch1, Address(rthread, Thread::polling_page_offset()));
 293     tbnz(rscratch1, exact_log2(SafepointMechanism::poll_bit()), slow_path);
 294   } else {
 295     unsigned long offset;
 296     adrp(rscratch1, ExternalAddress(SafepointSynchronize::address_of_state()), offset);
 297     ldrw(rscratch1, Address(rscratch1, offset));
 298     assert(SafepointSynchronize::_not_synchronized == 0, "rewrite this code");
 299     cbnz(rscratch1, slow_path);
 300   }
 301 }
 302 
 303 // Just like safepoint_poll, but use an acquiring load for thread-
 304 // local polling.
 305 //
 306 // We need an acquire here to ensure that any subsequent load of the
 307 // global SafepointSynchronize::_state flag is ordered after this load
 308 // of the local Thread::_polling page.  We don't want this poll to
 309 // return false (i.e. not safepointing) and a later poll of the global
 310 // SafepointSynchronize::_state spuriously to return true.
 311 //
 312 // This is to avoid a race when we're in a native->Java transition
 313 // racing the code which wakes up from a safepoint.
 314 //
 315 void MacroAssembler::safepoint_poll_acquire(Label& slow_path) {
 316   if (SafepointMechanism::uses_thread_local_poll()) {
 317     lea(rscratch1, Address(rthread, Thread::polling_page_offset()));
 318     ldar(rscratch1, rscratch1);
 319     tbnz(rscratch1, exact_log2(SafepointMechanism::poll_bit()), slow_path);
 320   } else {
 321     safepoint_poll(slow_path);
 322   }
 323 }
 324 
 325 void MacroAssembler::reset_last_Java_frame(bool clear_fp) {
 326   // we must set sp to zero to clear frame
 327   str(zr, Address(rthread, JavaThread::last_Java_sp_offset()));
 328 
 329   // must clear fp, so that compiled frames are not confused; it is
 330   // possible that we need it only for debugging
 331   if (clear_fp) {
 332     str(zr, Address(rthread, JavaThread::last_Java_fp_offset()));
 333   }
 334 
 335   // Always clear the pc because it could have been set by make_walkable()
 336   str(zr, Address(rthread, JavaThread::last_Java_pc_offset()));
 337 }
 338 
 339 // Calls to C land
 340 //
 341 // When entering C land, the rfp, & resp of the last Java frame have to be recorded
 342 // in the (thread-local) JavaThread object. When leaving C land, the last Java fp
 343 // has to be reset to 0. This is required to allow proper stack traversal.
 344 void MacroAssembler::set_last_Java_frame(Register last_java_sp,
 345                                          Register last_java_fp,
 346                                          Register last_java_pc,
 347                                          Register scratch) {
 348 
 349   if (last_java_pc->is_valid()) {
 350       str(last_java_pc, Address(rthread,
 351                                 JavaThread::frame_anchor_offset()
 352                                 + JavaFrameAnchor::last_Java_pc_offset()));
 353     }
 354 
 355   // determine last_java_sp register
 356   if (last_java_sp == sp) {
 357     mov(scratch, sp);
 358     last_java_sp = scratch;
 359   } else if (!last_java_sp->is_valid()) {
 360     last_java_sp = esp;
 361   }
 362 
 363   str(last_java_sp, Address(rthread, JavaThread::last_Java_sp_offset()));
 364 
 365   // last_java_fp is optional
 366   if (last_java_fp->is_valid()) {
 367     str(last_java_fp, Address(rthread, JavaThread::last_Java_fp_offset()));
 368   }
 369 }
 370 
 371 void MacroAssembler::set_last_Java_frame(Register last_java_sp,
 372                                          Register last_java_fp,
 373                                          address  last_java_pc,
 374                                          Register scratch) {
 375   if (last_java_pc != NULL) {
 376     adr(scratch, last_java_pc);
 377   } else {
 378     // FIXME: This is almost never correct.  We should delete all
 379     // cases of set_last_Java_frame with last_java_pc=NULL and use the
 380     // correct return address instead.
 381     adr(scratch, pc());
 382   }
 383 
 384   str(scratch, Address(rthread,
 385                        JavaThread::frame_anchor_offset()
 386                        + JavaFrameAnchor::last_Java_pc_offset()));
 387 
 388   set_last_Java_frame(last_java_sp, last_java_fp, noreg, scratch);
 389 }
 390 
 391 void MacroAssembler::set_last_Java_frame(Register last_java_sp,
 392                                          Register last_java_fp,
 393                                          Label &L,
 394                                          Register scratch) {
 395   if (L.is_bound()) {
 396     set_last_Java_frame(last_java_sp, last_java_fp, target(L), scratch);
 397   } else {
 398     InstructionMark im(this);
 399     L.add_patch_at(code(), locator());
 400     set_last_Java_frame(last_java_sp, last_java_fp, (address)NULL, scratch);
 401   }
 402 }
 403 
 404 void MacroAssembler::far_call(Address entry, CodeBuffer *cbuf, Register tmp) {
 405   assert(ReservedCodeCacheSize < 4*G, "branch out of range");
 406   assert(CodeCache::find_blob(entry.target()) != NULL,
 407          "destination of far call not found in code cache");
 408   if (far_branches()) {
 409     unsigned long offset;
 410     // We can use ADRP here because we know that the total size of
 411     // the code cache cannot exceed 2Gb.
 412     adrp(tmp, entry, offset);
 413     add(tmp, tmp, offset);
 414     if (cbuf) cbuf->set_insts_mark();
 415     blr(tmp);
 416   } else {
 417     if (cbuf) cbuf->set_insts_mark();
 418     bl(entry);
 419   }
 420 }
 421 
 422 void MacroAssembler::far_jump(Address entry, CodeBuffer *cbuf, Register tmp) {
 423   assert(ReservedCodeCacheSize < 4*G, "branch out of range");
 424   assert(CodeCache::find_blob(entry.target()) != NULL,
 425          "destination of far call not found in code cache");
 426   if (far_branches()) {
 427     unsigned long offset;
 428     // We can use ADRP here because we know that the total size of
 429     // the code cache cannot exceed 2Gb.
 430     adrp(tmp, entry, offset);
 431     add(tmp, tmp, offset);
 432     if (cbuf) cbuf->set_insts_mark();
 433     br(tmp);
 434   } else {
 435     if (cbuf) cbuf->set_insts_mark();
 436     b(entry);
 437   }
 438 }
 439 
 440 void MacroAssembler::reserved_stack_check() {
 441     // testing if reserved zone needs to be enabled
 442     Label no_reserved_zone_enabling;
 443 
 444     ldr(rscratch1, Address(rthread, JavaThread::reserved_stack_activation_offset()));
 445     cmp(sp, rscratch1);
 446     br(Assembler::LO, no_reserved_zone_enabling);
 447 
 448     enter();   // LR and FP are live.
 449     lea(rscratch1, CAST_FROM_FN_PTR(address, SharedRuntime::enable_stack_reserved_zone));
 450     mov(c_rarg0, rthread);
 451     blr(rscratch1);
 452     leave();
 453 
 454     // We have already removed our own frame.
 455     // throw_delayed_StackOverflowError will think that it's been
 456     // called by our caller.
 457     lea(rscratch1, RuntimeAddress(StubRoutines::throw_delayed_StackOverflowError_entry()));
 458     br(rscratch1);
 459     should_not_reach_here();
 460 
 461     bind(no_reserved_zone_enabling);
 462 }
 463 
 464 int MacroAssembler::biased_locking_enter(Register lock_reg,
 465                                          Register obj_reg,
 466                                          Register swap_reg,
 467                                          Register tmp_reg,
 468                                          bool swap_reg_contains_mark,
 469                                          Label& done,
 470                                          Label* slow_case,
 471                                          BiasedLockingCounters* counters) {
 472   assert(UseBiasedLocking, "why call this otherwise?");
 473   assert_different_registers(lock_reg, obj_reg, swap_reg);
 474 
 475   if (PrintBiasedLockingStatistics && counters == NULL)
 476     counters = BiasedLocking::counters();
 477 
 478   assert_different_registers(lock_reg, obj_reg, swap_reg, tmp_reg, rscratch1, rscratch2, noreg);
 479   assert(markOopDesc::age_shift == markOopDesc::lock_bits + markOopDesc::biased_lock_bits, "biased locking makes assumptions about bit layout");
 480   Address mark_addr      (obj_reg, oopDesc::mark_offset_in_bytes());
 481   Address klass_addr     (obj_reg, oopDesc::klass_offset_in_bytes());
 482   Address saved_mark_addr(lock_reg, 0);
 483 
 484   // Biased locking
 485   // See whether the lock is currently biased toward our thread and
 486   // whether the epoch is still valid
 487   // Note that the runtime guarantees sufficient alignment of JavaThread
 488   // pointers to allow age to be placed into low bits
 489   // First check to see whether biasing is even enabled for this object
 490   Label cas_label;
 491   int null_check_offset = -1;
 492   if (!swap_reg_contains_mark) {
 493     null_check_offset = offset();
 494     ldr(swap_reg, mark_addr);
 495   }
 496   andr(tmp_reg, swap_reg, markOopDesc::biased_lock_mask_in_place);
 497   cmp(tmp_reg, markOopDesc::biased_lock_pattern);
 498   br(Assembler::NE, cas_label);
 499   // The bias pattern is present in the object's header. Need to check
 500   // whether the bias owner and the epoch are both still current.
 501   load_prototype_header(tmp_reg, obj_reg);
 502   orr(tmp_reg, tmp_reg, rthread);
 503   eor(tmp_reg, swap_reg, tmp_reg);
 504   andr(tmp_reg, tmp_reg, ~((int) markOopDesc::age_mask_in_place));
 505   if (counters != NULL) {
 506     Label around;
 507     cbnz(tmp_reg, around);
 508     atomic_incw(Address((address)counters->biased_lock_entry_count_addr()), tmp_reg, rscratch1, rscratch2);
 509     b(done);
 510     bind(around);
 511   } else {
 512     cbz(tmp_reg, done);
 513   }
 514 
 515   Label try_revoke_bias;
 516   Label try_rebias;
 517 
 518   // At this point we know that the header has the bias pattern and
 519   // that we are not the bias owner in the current epoch. We need to
 520   // figure out more details about the state of the header in order to
 521   // know what operations can be legally performed on the object's
 522   // header.
 523 
 524   // If the low three bits in the xor result aren't clear, that means
 525   // the prototype header is no longer biased and we have to revoke
 526   // the bias on this object.
 527   andr(rscratch1, tmp_reg, markOopDesc::biased_lock_mask_in_place);
 528   cbnz(rscratch1, try_revoke_bias);
 529 
 530   // Biasing is still enabled for this data type. See whether the
 531   // epoch of the current bias is still valid, meaning that the epoch
 532   // bits of the mark word are equal to the epoch bits of the
 533   // prototype header. (Note that the prototype header's epoch bits
 534   // only change at a safepoint.) If not, attempt to rebias the object
 535   // toward the current thread. Note that we must be absolutely sure
 536   // that the current epoch is invalid in order to do this because
 537   // otherwise the manipulations it performs on the mark word are
 538   // illegal.
 539   andr(rscratch1, tmp_reg, markOopDesc::epoch_mask_in_place);
 540   cbnz(rscratch1, try_rebias);
 541 
 542   // The epoch of the current bias is still valid but we know nothing
 543   // about the owner; it might be set or it might be clear. Try to
 544   // acquire the bias of the object using an atomic operation. If this
 545   // fails we will go in to the runtime to revoke the object's bias.
 546   // Note that we first construct the presumed unbiased header so we
 547   // don't accidentally blow away another thread's valid bias.
 548   {
 549     Label here;
 550     mov(rscratch1, markOopDesc::biased_lock_mask_in_place | markOopDesc::age_mask_in_place | markOopDesc::epoch_mask_in_place);
 551     andr(swap_reg, swap_reg, rscratch1);
 552     orr(tmp_reg, swap_reg, rthread);
 553     cmpxchg_obj_header(swap_reg, tmp_reg, obj_reg, rscratch1, here, slow_case);
 554     // If the biasing toward our thread failed, this means that
 555     // another thread succeeded in biasing it toward itself and we
 556     // need to revoke that bias. The revocation will occur in the
 557     // interpreter runtime in the slow case.
 558     bind(here);
 559     if (counters != NULL) {
 560       atomic_incw(Address((address)counters->anonymously_biased_lock_entry_count_addr()),
 561                   tmp_reg, rscratch1, rscratch2);
 562     }
 563   }
 564   b(done);
 565 
 566   bind(try_rebias);
 567   // At this point we know the epoch has expired, meaning that the
 568   // current "bias owner", if any, is actually invalid. Under these
 569   // circumstances _only_, we are allowed to use the current header's
 570   // value as the comparison value when doing the cas to acquire the
 571   // bias in the current epoch. In other words, we allow transfer of
 572   // the bias from one thread to another directly in this situation.
 573   //
 574   // FIXME: due to a lack of registers we currently blow away the age
 575   // bits in this situation. Should attempt to preserve them.
 576   {
 577     Label here;
 578     load_prototype_header(tmp_reg, obj_reg);
 579     orr(tmp_reg, rthread, tmp_reg);
 580     cmpxchg_obj_header(swap_reg, tmp_reg, obj_reg, rscratch1, here, slow_case);
 581     // If the biasing toward our thread failed, then another thread
 582     // succeeded in biasing it toward itself and we need to revoke that
 583     // bias. The revocation will occur in the runtime in the slow case.
 584     bind(here);
 585     if (counters != NULL) {
 586       atomic_incw(Address((address)counters->rebiased_lock_entry_count_addr()),
 587                   tmp_reg, rscratch1, rscratch2);
 588     }
 589   }
 590   b(done);
 591 
 592   bind(try_revoke_bias);
 593   // The prototype mark in the klass doesn't have the bias bit set any
 594   // more, indicating that objects of this data type are not supposed
 595   // to be biased any more. We are going to try to reset the mark of
 596   // this object to the prototype value and fall through to the
 597   // CAS-based locking scheme. Note that if our CAS fails, it means
 598   // that another thread raced us for the privilege of revoking the
 599   // bias of this particular object, so it's okay to continue in the
 600   // normal locking code.
 601   //
 602   // FIXME: due to a lack of registers we currently blow away the age
 603   // bits in this situation. Should attempt to preserve them.
 604   {
 605     Label here, nope;
 606     load_prototype_header(tmp_reg, obj_reg);
 607     cmpxchg_obj_header(swap_reg, tmp_reg, obj_reg, rscratch1, here, &nope);
 608     bind(here);
 609 
 610     // Fall through to the normal CAS-based lock, because no matter what
 611     // the result of the above CAS, some thread must have succeeded in
 612     // removing the bias bit from the object's header.
 613     if (counters != NULL) {
 614       atomic_incw(Address((address)counters->revoked_lock_entry_count_addr()), tmp_reg,
 615                   rscratch1, rscratch2);
 616     }
 617     bind(nope);
 618   }
 619 
 620   bind(cas_label);
 621 
 622   return null_check_offset;
 623 }
 624 
 625 void MacroAssembler::biased_locking_exit(Register obj_reg, Register temp_reg, Label& done) {
 626   assert(UseBiasedLocking, "why call this otherwise?");
 627 
 628   // Check for biased locking unlock case, which is a no-op
 629   // Note: we do not have to check the thread ID for two reasons.
 630   // First, the interpreter checks for IllegalMonitorStateException at
 631   // a higher level. Second, if the bias was revoked while we held the
 632   // lock, the object could not be rebiased toward another thread, so
 633   // the bias bit would be clear.
 634   ldr(temp_reg, Address(obj_reg, oopDesc::mark_offset_in_bytes()));
 635   andr(temp_reg, temp_reg, markOopDesc::biased_lock_mask_in_place);
 636   cmp(temp_reg, markOopDesc::biased_lock_pattern);
 637   br(Assembler::EQ, done);
 638 }
 639 
 640 static void pass_arg0(MacroAssembler* masm, Register arg) {
 641   if (c_rarg0 != arg ) {
 642     masm->mov(c_rarg0, arg);
 643   }
 644 }
 645 
 646 static void pass_arg1(MacroAssembler* masm, Register arg) {
 647   if (c_rarg1 != arg ) {
 648     masm->mov(c_rarg1, arg);
 649   }
 650 }
 651 
 652 static void pass_arg2(MacroAssembler* masm, Register arg) {
 653   if (c_rarg2 != arg ) {
 654     masm->mov(c_rarg2, arg);
 655   }
 656 }
 657 
 658 static void pass_arg3(MacroAssembler* masm, Register arg) {
 659   if (c_rarg3 != arg ) {
 660     masm->mov(c_rarg3, arg);
 661   }
 662 }
 663 
 664 void MacroAssembler::call_VM_base(Register oop_result,
 665                                   Register java_thread,
 666                                   Register last_java_sp,
 667                                   address  entry_point,
 668                                   int      number_of_arguments,
 669                                   bool     check_exceptions) {
 670    // determine java_thread register
 671   if (!java_thread->is_valid()) {
 672     java_thread = rthread;
 673   }
 674 
 675   // determine last_java_sp register
 676   if (!last_java_sp->is_valid()) {
 677     last_java_sp = esp;
 678   }
 679 
 680   // debugging support
 681   assert(number_of_arguments >= 0   , "cannot have negative number of arguments");
 682   assert(java_thread == rthread, "unexpected register");
 683 #ifdef ASSERT
 684   // TraceBytecodes does not use r12 but saves it over the call, so don't verify
 685   // if ((UseCompressedOops || UseCompressedClassPointers) && !TraceBytecodes) verify_heapbase("call_VM_base: heap base corrupted?");
 686 #endif // ASSERT
 687 
 688   assert(java_thread != oop_result  , "cannot use the same register for java_thread & oop_result");
 689   assert(java_thread != last_java_sp, "cannot use the same register for java_thread & last_java_sp");
 690 
 691   // push java thread (becomes first argument of C function)
 692 
 693   mov(c_rarg0, java_thread);
 694 
 695   // set last Java frame before call
 696   assert(last_java_sp != rfp, "can't use rfp");
 697 
 698   Label l;
 699   set_last_Java_frame(last_java_sp, rfp, l, rscratch1);
 700 
 701   // do the call, remove parameters
 702   MacroAssembler::call_VM_leaf_base(entry_point, number_of_arguments, &l);
 703 
 704   // reset last Java frame
 705   // Only interpreter should have to clear fp
 706   reset_last_Java_frame(true);
 707 
 708    // C++ interp handles this in the interpreter
 709   check_and_handle_popframe(java_thread);
 710   check_and_handle_earlyret(java_thread);
 711 
 712   if (check_exceptions) {
 713     // check for pending exceptions (java_thread is set upon return)
 714     ldr(rscratch1, Address(java_thread, in_bytes(Thread::pending_exception_offset())));
 715     Label ok;
 716     cbz(rscratch1, ok);
 717     lea(rscratch1, RuntimeAddress(StubRoutines::forward_exception_entry()));
 718     br(rscratch1);
 719     bind(ok);
 720   }
 721 
 722   // get oop result if there is one and reset the value in the thread
 723   if (oop_result->is_valid()) {
 724     get_vm_result(oop_result, java_thread);
 725   }
 726 }
 727 
 728 void MacroAssembler::call_VM_helper(Register oop_result, address entry_point, int number_of_arguments, bool check_exceptions) {
 729   call_VM_base(oop_result, noreg, noreg, entry_point, number_of_arguments, check_exceptions);
 730 }
 731 
 732 // Maybe emit a call via a trampoline.  If the code cache is small
 733 // trampolines won't be emitted.
 734 
 735 address MacroAssembler::trampoline_call(Address entry, CodeBuffer *cbuf) {
 736   assert(JavaThread::current()->is_Compiler_thread(), "just checking");
 737   assert(entry.rspec().type() == relocInfo::runtime_call_type
 738          || entry.rspec().type() == relocInfo::opt_virtual_call_type
 739          || entry.rspec().type() == relocInfo::static_call_type
 740          || entry.rspec().type() == relocInfo::virtual_call_type, "wrong reloc type");
 741 
 742   unsigned int start_offset = offset();
 743   if (far_branches() && !Compile::current()->in_scratch_emit_size()) {
 744     address stub = emit_trampoline_stub(start_offset, entry.target());
 745     if (stub == NULL) {
 746       return NULL; // CodeCache is full
 747     }
 748   }
 749 
 750   if (cbuf) cbuf->set_insts_mark();
 751   relocate(entry.rspec());
 752   if (!far_branches()) {
 753     bl(entry.target());
 754   } else {
 755     bl(pc());
 756   }
 757   // just need to return a non-null address
 758   return pc();
 759 }
 760 
 761 
 762 // Emit a trampoline stub for a call to a target which is too far away.
 763 //
 764 // code sequences:
 765 //
 766 // call-site:
 767 //   branch-and-link to <destination> or <trampoline stub>
 768 //
 769 // Related trampoline stub for this call site in the stub section:
 770 //   load the call target from the constant pool
 771 //   branch (LR still points to the call site above)
 772 
 773 address MacroAssembler::emit_trampoline_stub(int insts_call_instruction_offset,
 774                                              address dest) {
 775   address stub = start_a_stub(Compile::MAX_stubs_size/2);
 776   if (stub == NULL) {
 777     return NULL;  // CodeBuffer::expand failed
 778   }
 779 
 780   // Create a trampoline stub relocation which relates this trampoline stub
 781   // with the call instruction at insts_call_instruction_offset in the
 782   // instructions code-section.
 783   align(wordSize);
 784   relocate(trampoline_stub_Relocation::spec(code()->insts()->start()
 785                                             + insts_call_instruction_offset));
 786   const int stub_start_offset = offset();
 787 
 788   // Now, create the trampoline stub's code:
 789   // - load the call
 790   // - call
 791   Label target;
 792   ldr(rscratch1, target);
 793   br(rscratch1);
 794   bind(target);
 795   assert(offset() - stub_start_offset == NativeCallTrampolineStub::data_offset,
 796          "should be");
 797   emit_int64((int64_t)dest);
 798 
 799   const address stub_start_addr = addr_at(stub_start_offset);
 800 
 801   assert(is_NativeCallTrampolineStub_at(stub_start_addr), "doesn't look like a trampoline");
 802 
 803   end_a_stub();
 804   return stub_start_addr;
 805 }
 806 
 807 address MacroAssembler::ic_call(address entry, jint method_index) {
 808   RelocationHolder rh = virtual_call_Relocation::spec(pc(), method_index);
 809   // address const_ptr = long_constant((jlong)Universe::non_oop_word());
 810   // unsigned long offset;
 811   // ldr_constant(rscratch2, const_ptr);
 812   movptr(rscratch2, (uintptr_t)Universe::non_oop_word());
 813   return trampoline_call(Address(entry, rh));
 814 }
 815 
 816 // Implementation of call_VM versions
 817 
 818 void MacroAssembler::call_VM(Register oop_result,
 819                              address entry_point,
 820                              bool check_exceptions) {
 821   call_VM_helper(oop_result, entry_point, 0, check_exceptions);
 822 }
 823 
 824 void MacroAssembler::call_VM(Register oop_result,
 825                              address entry_point,
 826                              Register arg_1,
 827                              bool check_exceptions) {
 828   pass_arg1(this, arg_1);
 829   call_VM_helper(oop_result, entry_point, 1, check_exceptions);
 830 }
 831 
 832 void MacroAssembler::call_VM(Register oop_result,
 833                              address entry_point,
 834                              Register arg_1,
 835                              Register arg_2,
 836                              bool check_exceptions) {
 837   assert(arg_1 != c_rarg2, "smashed arg");
 838   pass_arg2(this, arg_2);
 839   pass_arg1(this, arg_1);
 840   call_VM_helper(oop_result, entry_point, 2, check_exceptions);
 841 }
 842 
 843 void MacroAssembler::call_VM(Register oop_result,
 844                              address entry_point,
 845                              Register arg_1,
 846                              Register arg_2,
 847                              Register arg_3,
 848                              bool check_exceptions) {
 849   assert(arg_1 != c_rarg3, "smashed arg");
 850   assert(arg_2 != c_rarg3, "smashed arg");
 851   pass_arg3(this, arg_3);
 852 
 853   assert(arg_1 != c_rarg2, "smashed arg");
 854   pass_arg2(this, arg_2);
 855 
 856   pass_arg1(this, arg_1);
 857   call_VM_helper(oop_result, entry_point, 3, check_exceptions);
 858 }
 859 
 860 void MacroAssembler::call_VM(Register oop_result,
 861                              Register last_java_sp,
 862                              address entry_point,
 863                              int number_of_arguments,
 864                              bool check_exceptions) {
 865   call_VM_base(oop_result, rthread, last_java_sp, entry_point, number_of_arguments, check_exceptions);
 866 }
 867 
 868 void MacroAssembler::call_VM(Register oop_result,
 869                              Register last_java_sp,
 870                              address entry_point,
 871                              Register arg_1,
 872                              bool check_exceptions) {
 873   pass_arg1(this, arg_1);
 874   call_VM(oop_result, last_java_sp, entry_point, 1, check_exceptions);
 875 }
 876 
 877 void MacroAssembler::call_VM(Register oop_result,
 878                              Register last_java_sp,
 879                              address entry_point,
 880                              Register arg_1,
 881                              Register arg_2,
 882                              bool check_exceptions) {
 883 
 884   assert(arg_1 != c_rarg2, "smashed arg");
 885   pass_arg2(this, arg_2);
 886   pass_arg1(this, arg_1);
 887   call_VM(oop_result, last_java_sp, entry_point, 2, check_exceptions);
 888 }
 889 
 890 void MacroAssembler::call_VM(Register oop_result,
 891                              Register last_java_sp,
 892                              address entry_point,
 893                              Register arg_1,
 894                              Register arg_2,
 895                              Register arg_3,
 896                              bool check_exceptions) {
 897   assert(arg_1 != c_rarg3, "smashed arg");
 898   assert(arg_2 != c_rarg3, "smashed arg");
 899   pass_arg3(this, arg_3);
 900   assert(arg_1 != c_rarg2, "smashed arg");
 901   pass_arg2(this, arg_2);
 902   pass_arg1(this, arg_1);
 903   call_VM(oop_result, last_java_sp, entry_point, 3, check_exceptions);
 904 }
 905 
 906 
 907 void MacroAssembler::get_vm_result(Register oop_result, Register java_thread) {
 908   ldr(oop_result, Address(java_thread, JavaThread::vm_result_offset()));
 909   str(zr, Address(java_thread, JavaThread::vm_result_offset()));
 910   verify_oop(oop_result, "broken oop in call_VM_base");
 911 }
 912 
 913 void MacroAssembler::get_vm_result_2(Register metadata_result, Register java_thread) {
 914   ldr(metadata_result, Address(java_thread, JavaThread::vm_result_2_offset()));
 915   str(zr, Address(java_thread, JavaThread::vm_result_2_offset()));
 916 }
 917 
 918 void MacroAssembler::align(int modulus) {
 919   while (offset() % modulus != 0) nop();
 920 }
 921 
 922 // these are no-ops overridden by InterpreterMacroAssembler
 923 
 924 void MacroAssembler::check_and_handle_earlyret(Register java_thread) { }
 925 
 926 void MacroAssembler::check_and_handle_popframe(Register java_thread) { }
 927 
 928 
 929 RegisterOrConstant MacroAssembler::delayed_value_impl(intptr_t* delayed_value_addr,
 930                                                       Register tmp,
 931                                                       int offset) {
 932   intptr_t value = *delayed_value_addr;
 933   if (value != 0)
 934     return RegisterOrConstant(value + offset);
 935 
 936   // load indirectly to solve generation ordering problem
 937   ldr(tmp, ExternalAddress((address) delayed_value_addr));
 938 
 939   if (offset != 0)
 940     add(tmp, tmp, offset);
 941 
 942   return RegisterOrConstant(tmp);
 943 }
 944 
 945 
 946 void MacroAssembler:: notify(int type) {
 947   if (type == bytecode_start) {
 948     // set_last_Java_frame(esp, rfp, (address)NULL);
 949     Assembler:: notify(type);
 950     // reset_last_Java_frame(true);
 951   }
 952   else
 953     Assembler:: notify(type);
 954 }
 955 
 956 // Look up the method for a megamorphic invokeinterface call.
 957 // The target method is determined by <intf_klass, itable_index>.
 958 // The receiver klass is in recv_klass.
 959 // On success, the result will be in method_result, and execution falls through.
 960 // On failure, execution transfers to the given label.
 961 void MacroAssembler::lookup_interface_method(Register recv_klass,
 962                                              Register intf_klass,
 963                                              RegisterOrConstant itable_index,
 964                                              Register method_result,
 965                                              Register scan_temp,
 966                                              Label& L_no_such_interface,
 967                          bool return_method) {
 968   assert_different_registers(recv_klass, intf_klass, scan_temp);
 969   assert_different_registers(method_result, intf_klass, scan_temp);
 970   assert(recv_klass != method_result || !return_method,
 971      "recv_klass can be destroyed when method isn't needed");
 972   assert(itable_index.is_constant() || itable_index.as_register() == method_result,
 973          "caller must use same register for non-constant itable index as for method");
 974 
 975   // Compute start of first itableOffsetEntry (which is at the end of the vtable)
 976   int vtable_base = in_bytes(Klass::vtable_start_offset());
 977   int itentry_off = itableMethodEntry::method_offset_in_bytes();
 978   int scan_step   = itableOffsetEntry::size() * wordSize;
 979   int vte_size    = vtableEntry::size_in_bytes();
 980   assert(vte_size == wordSize, "else adjust times_vte_scale");
 981 
 982   ldrw(scan_temp, Address(recv_klass, Klass::vtable_length_offset()));
 983 
 984   // %%% Could store the aligned, prescaled offset in the klassoop.
 985   // lea(scan_temp, Address(recv_klass, scan_temp, times_vte_scale, vtable_base));
 986   lea(scan_temp, Address(recv_klass, scan_temp, Address::lsl(3)));
 987   add(scan_temp, scan_temp, vtable_base);
 988 
 989   if (return_method) {
 990     // Adjust recv_klass by scaled itable_index, so we can free itable_index.
 991     assert(itableMethodEntry::size() * wordSize == wordSize, "adjust the scaling in the code below");
 992     // lea(recv_klass, Address(recv_klass, itable_index, Address::times_ptr, itentry_off));
 993     lea(recv_klass, Address(recv_klass, itable_index, Address::lsl(3)));
 994     if (itentry_off)
 995       add(recv_klass, recv_klass, itentry_off);
 996   }
 997 
 998   // for (scan = klass->itable(); scan->interface() != NULL; scan += scan_step) {
 999   //   if (scan->interface() == intf) {
1000   //     result = (klass + scan->offset() + itable_index);
1001   //   }
1002   // }
1003   Label search, found_method;
1004 
1005   for (int peel = 1; peel >= 0; peel--) {
1006     ldr(method_result, Address(scan_temp, itableOffsetEntry::interface_offset_in_bytes()));
1007     cmp(intf_klass, method_result);
1008 
1009     if (peel) {
1010       br(Assembler::EQ, found_method);
1011     } else {
1012       br(Assembler::NE, search);
1013       // (invert the test to fall through to found_method...)
1014     }
1015 
1016     if (!peel)  break;
1017 
1018     bind(search);
1019 
1020     // Check that the previous entry is non-null.  A null entry means that
1021     // the receiver class doesn't implement the interface, and wasn't the
1022     // same as when the caller was compiled.
1023     cbz(method_result, L_no_such_interface);
1024     add(scan_temp, scan_temp, scan_step);
1025   }
1026 
1027   bind(found_method);
1028 
1029   // Got a hit.
1030   if (return_method) {
1031     ldrw(scan_temp, Address(scan_temp, itableOffsetEntry::offset_offset_in_bytes()));
1032     ldr(method_result, Address(recv_klass, scan_temp, Address::uxtw(0)));
1033   }
1034 }
1035 
1036 // virtual method calling
1037 void MacroAssembler::lookup_virtual_method(Register recv_klass,
1038                                            RegisterOrConstant vtable_index,
1039                                            Register method_result) {
1040   const int base = in_bytes(Klass::vtable_start_offset());
1041   assert(vtableEntry::size() * wordSize == 8,
1042          "adjust the scaling in the code below");
1043   int vtable_offset_in_bytes = base + vtableEntry::method_offset_in_bytes();
1044 
1045   if (vtable_index.is_register()) {
1046     lea(method_result, Address(recv_klass,
1047                                vtable_index.as_register(),
1048                                Address::lsl(LogBytesPerWord)));
1049     ldr(method_result, Address(method_result, vtable_offset_in_bytes));
1050   } else {
1051     vtable_offset_in_bytes += vtable_index.as_constant() * wordSize;
1052     ldr(method_result,
1053         form_address(rscratch1, recv_klass, vtable_offset_in_bytes, 0));
1054   }
1055 }
1056 
1057 void MacroAssembler::check_klass_subtype(Register sub_klass,
1058                            Register super_klass,
1059                            Register temp_reg,
1060                            Label& L_success) {
1061   Label L_failure;
1062   check_klass_subtype_fast_path(sub_klass, super_klass, temp_reg,        &L_success, &L_failure, NULL);
1063   check_klass_subtype_slow_path(sub_klass, super_klass, temp_reg, noreg, &L_success, NULL);
1064   bind(L_failure);
1065 }
1066 
1067 
1068 void MacroAssembler::check_klass_subtype_fast_path(Register sub_klass,
1069                                                    Register super_klass,
1070                                                    Register temp_reg,
1071                                                    Label* L_success,
1072                                                    Label* L_failure,
1073                                                    Label* L_slow_path,
1074                                         RegisterOrConstant super_check_offset) {
1075   assert_different_registers(sub_klass, super_klass, temp_reg);
1076   bool must_load_sco = (super_check_offset.constant_or_zero() == -1);
1077   if (super_check_offset.is_register()) {
1078     assert_different_registers(sub_klass, super_klass,
1079                                super_check_offset.as_register());
1080   } else if (must_load_sco) {
1081     assert(temp_reg != noreg, "supply either a temp or a register offset");
1082   }
1083 
1084   Label L_fallthrough;
1085   int label_nulls = 0;
1086   if (L_success == NULL)   { L_success   = &L_fallthrough; label_nulls++; }
1087   if (L_failure == NULL)   { L_failure   = &L_fallthrough; label_nulls++; }
1088   if (L_slow_path == NULL) { L_slow_path = &L_fallthrough; label_nulls++; }
1089   assert(label_nulls <= 1, "at most one NULL in the batch");
1090 
1091   int sc_offset = in_bytes(Klass::secondary_super_cache_offset());
1092   int sco_offset = in_bytes(Klass::super_check_offset_offset());
1093   Address super_check_offset_addr(super_klass, sco_offset);
1094 
1095   // Hacked jmp, which may only be used just before L_fallthrough.
1096 #define final_jmp(label)                                                \
1097   if (&(label) == &L_fallthrough) { /*do nothing*/ }                    \
1098   else                            b(label)                /*omit semi*/
1099 
1100   // If the pointers are equal, we are done (e.g., String[] elements).
1101   // This self-check enables sharing of secondary supertype arrays among
1102   // non-primary types such as array-of-interface.  Otherwise, each such
1103   // type would need its own customized SSA.
1104   // We move this check to the front of the fast path because many
1105   // type checks are in fact trivially successful in this manner,
1106   // so we get a nicely predicted branch right at the start of the check.
1107   cmp(sub_klass, super_klass);
1108   br(Assembler::EQ, *L_success);
1109 
1110   // Check the supertype display:
1111   if (must_load_sco) {
1112     ldrw(temp_reg, super_check_offset_addr);
1113     super_check_offset = RegisterOrConstant(temp_reg);
1114   }
1115   Address super_check_addr(sub_klass, super_check_offset);
1116   ldr(rscratch1, super_check_addr);
1117   cmp(super_klass, rscratch1); // load displayed supertype
1118 
1119   // This check has worked decisively for primary supers.
1120   // Secondary supers are sought in the super_cache ('super_cache_addr').
1121   // (Secondary supers are interfaces and very deeply nested subtypes.)
1122   // This works in the same check above because of a tricky aliasing
1123   // between the super_cache and the primary super display elements.
1124   // (The 'super_check_addr' can address either, as the case requires.)
1125   // Note that the cache is updated below if it does not help us find
1126   // what we need immediately.
1127   // So if it was a primary super, we can just fail immediately.
1128   // Otherwise, it's the slow path for us (no success at this point).
1129 
1130   if (super_check_offset.is_register()) {
1131     br(Assembler::EQ, *L_success);
1132     cmp(super_check_offset.as_register(), sc_offset);
1133     if (L_failure == &L_fallthrough) {
1134       br(Assembler::EQ, *L_slow_path);
1135     } else {
1136       br(Assembler::NE, *L_failure);
1137       final_jmp(*L_slow_path);
1138     }
1139   } else if (super_check_offset.as_constant() == sc_offset) {
1140     // Need a slow path; fast failure is impossible.
1141     if (L_slow_path == &L_fallthrough) {
1142       br(Assembler::EQ, *L_success);
1143     } else {
1144       br(Assembler::NE, *L_slow_path);
1145       final_jmp(*L_success);
1146     }
1147   } else {
1148     // No slow path; it's a fast decision.
1149     if (L_failure == &L_fallthrough) {
1150       br(Assembler::EQ, *L_success);
1151     } else {
1152       br(Assembler::NE, *L_failure);
1153       final_jmp(*L_success);
1154     }
1155   }
1156 
1157   bind(L_fallthrough);
1158 
1159 #undef final_jmp
1160 }
1161 
1162 // These two are taken from x86, but they look generally useful
1163 
1164 // scans count pointer sized words at [addr] for occurence of value,
1165 // generic
1166 void MacroAssembler::repne_scan(Register addr, Register value, Register count,
1167                                 Register scratch) {
1168   Label Lloop, Lexit;
1169   cbz(count, Lexit);
1170   bind(Lloop);
1171   ldr(scratch, post(addr, wordSize));
1172   cmp(value, scratch);
1173   br(EQ, Lexit);
1174   sub(count, count, 1);
1175   cbnz(count, Lloop);
1176   bind(Lexit);
1177 }
1178 
1179 // scans count 4 byte words at [addr] for occurence of value,
1180 // generic
1181 void MacroAssembler::repne_scanw(Register addr, Register value, Register count,
1182                                 Register scratch) {
1183   Label Lloop, Lexit;
1184   cbz(count, Lexit);
1185   bind(Lloop);
1186   ldrw(scratch, post(addr, wordSize));
1187   cmpw(value, scratch);
1188   br(EQ, Lexit);
1189   sub(count, count, 1);
1190   cbnz(count, Lloop);
1191   bind(Lexit);
1192 }
1193 
1194 void MacroAssembler::check_klass_subtype_slow_path(Register sub_klass,
1195                                                    Register super_klass,
1196                                                    Register temp_reg,
1197                                                    Register temp2_reg,
1198                                                    Label* L_success,
1199                                                    Label* L_failure,
1200                                                    bool set_cond_codes) {
1201   assert_different_registers(sub_klass, super_klass, temp_reg);
1202   if (temp2_reg != noreg)
1203     assert_different_registers(sub_klass, super_klass, temp_reg, temp2_reg, rscratch1);
1204 #define IS_A_TEMP(reg) ((reg) == temp_reg || (reg) == temp2_reg)
1205 
1206   Label L_fallthrough;
1207   int label_nulls = 0;
1208   if (L_success == NULL)   { L_success   = &L_fallthrough; label_nulls++; }
1209   if (L_failure == NULL)   { L_failure   = &L_fallthrough; label_nulls++; }
1210   assert(label_nulls <= 1, "at most one NULL in the batch");
1211 
1212   // a couple of useful fields in sub_klass:
1213   int ss_offset = in_bytes(Klass::secondary_supers_offset());
1214   int sc_offset = in_bytes(Klass::secondary_super_cache_offset());
1215   Address secondary_supers_addr(sub_klass, ss_offset);
1216   Address super_cache_addr(     sub_klass, sc_offset);
1217 
1218   BLOCK_COMMENT("check_klass_subtype_slow_path");
1219 
1220   // Do a linear scan of the secondary super-klass chain.
1221   // This code is rarely used, so simplicity is a virtue here.
1222   // The repne_scan instruction uses fixed registers, which we must spill.
1223   // Don't worry too much about pre-existing connections with the input regs.
1224 
1225   assert(sub_klass != r0, "killed reg"); // killed by mov(r0, super)
1226   assert(sub_klass != r2, "killed reg"); // killed by lea(r2, &pst_counter)
1227 
1228   RegSet pushed_registers;
1229   if (!IS_A_TEMP(r2))    pushed_registers += r2;
1230   if (!IS_A_TEMP(r5))    pushed_registers += r5;
1231 
1232   if (super_klass != r0 || UseCompressedOops) {
1233     if (!IS_A_TEMP(r0))   pushed_registers += r0;
1234   }
1235 
1236   push(pushed_registers, sp);
1237 
1238   // Get super_klass value into r0 (even if it was in r5 or r2).
1239   if (super_klass != r0) {
1240     mov(r0, super_klass);
1241   }
1242 
1243 #ifndef PRODUCT
1244   mov(rscratch2, (address)&SharedRuntime::_partial_subtype_ctr);
1245   Address pst_counter_addr(rscratch2);
1246   ldr(rscratch1, pst_counter_addr);
1247   add(rscratch1, rscratch1, 1);
1248   str(rscratch1, pst_counter_addr);
1249 #endif //PRODUCT
1250 
1251   // We will consult the secondary-super array.
1252   ldr(r5, secondary_supers_addr);
1253   // Load the array length.
1254   ldrw(r2, Address(r5, Array<Klass*>::length_offset_in_bytes()));
1255   // Skip to start of data.
1256   add(r5, r5, Array<Klass*>::base_offset_in_bytes());
1257 
1258   cmp(sp, zr); // Clear Z flag; SP is never zero
1259   // Scan R2 words at [R5] for an occurrence of R0.
1260   // Set NZ/Z based on last compare.
1261   repne_scan(r5, r0, r2, rscratch1);
1262 
1263   // Unspill the temp. registers:
1264   pop(pushed_registers, sp);
1265 
1266   br(Assembler::NE, *L_failure);
1267 
1268   // Success.  Cache the super we found and proceed in triumph.
1269   str(super_klass, super_cache_addr);
1270 
1271   if (L_success != &L_fallthrough) {
1272     b(*L_success);
1273   }
1274 
1275 #undef IS_A_TEMP
1276 
1277   bind(L_fallthrough);
1278 }
1279 
1280 
1281 void MacroAssembler::verify_oop(Register reg, const char* s) {
1282   if (!VerifyOops) return;
1283 
1284   // Pass register number to verify_oop_subroutine
1285   const char* b = NULL;
1286   {
1287     ResourceMark rm;
1288     stringStream ss;
1289     ss.print("verify_oop: %s: %s", reg->name(), s);
1290     b = code_string(ss.as_string());
1291   }
1292   BLOCK_COMMENT("verify_oop {");
1293 
1294   stp(r0, rscratch1, Address(pre(sp, -2 * wordSize)));
1295   stp(rscratch2, lr, Address(pre(sp, -2 * wordSize)));
1296 
1297   mov(r0, reg);
1298   mov(rscratch1, (address)b);
1299 
1300   // call indirectly to solve generation ordering problem
1301   lea(rscratch2, ExternalAddress(StubRoutines::verify_oop_subroutine_entry_address()));
1302   ldr(rscratch2, Address(rscratch2));
1303   blr(rscratch2);
1304 
1305   ldp(rscratch2, lr, Address(post(sp, 2 * wordSize)));
1306   ldp(r0, rscratch1, Address(post(sp, 2 * wordSize)));
1307 
1308   BLOCK_COMMENT("} verify_oop");
1309 }
1310 
1311 void MacroAssembler::verify_oop_addr(Address addr, const char* s) {
1312   if (!VerifyOops) return;
1313 
1314   const char* b = NULL;
1315   {
1316     ResourceMark rm;
1317     stringStream ss;
1318     ss.print("verify_oop_addr: %s", s);
1319     b = code_string(ss.as_string());
1320   }
1321   BLOCK_COMMENT("verify_oop_addr {");
1322 
1323   stp(r0, rscratch1, Address(pre(sp, -2 * wordSize)));
1324   stp(rscratch2, lr, Address(pre(sp, -2 * wordSize)));
1325 
1326   // addr may contain sp so we will have to adjust it based on the
1327   // pushes that we just did.
1328   if (addr.uses(sp)) {
1329     lea(r0, addr);
1330     ldr(r0, Address(r0, 4 * wordSize));
1331   } else {
1332     ldr(r0, addr);
1333   }
1334   mov(rscratch1, (address)b);
1335 
1336   // call indirectly to solve generation ordering problem
1337   lea(rscratch2, ExternalAddress(StubRoutines::verify_oop_subroutine_entry_address()));
1338   ldr(rscratch2, Address(rscratch2));
1339   blr(rscratch2);
1340 
1341   ldp(rscratch2, lr, Address(post(sp, 2 * wordSize)));
1342   ldp(r0, rscratch1, Address(post(sp, 2 * wordSize)));
1343 
1344   BLOCK_COMMENT("} verify_oop_addr");
1345 }
1346 
1347 Address MacroAssembler::argument_address(RegisterOrConstant arg_slot,
1348                                          int extra_slot_offset) {
1349   // cf. TemplateTable::prepare_invoke(), if (load_receiver).
1350   int stackElementSize = Interpreter::stackElementSize;
1351   int offset = Interpreter::expr_offset_in_bytes(extra_slot_offset+0);
1352 #ifdef ASSERT
1353   int offset1 = Interpreter::expr_offset_in_bytes(extra_slot_offset+1);
1354   assert(offset1 - offset == stackElementSize, "correct arithmetic");
1355 #endif
1356   if (arg_slot.is_constant()) {
1357     return Address(esp, arg_slot.as_constant() * stackElementSize
1358                    + offset);
1359   } else {
1360     add(rscratch1, esp, arg_slot.as_register(),
1361         ext::uxtx, exact_log2(stackElementSize));
1362     return Address(rscratch1, offset);
1363   }
1364 }
1365 
1366 void MacroAssembler::call_VM_leaf_base(address entry_point,
1367                                        int number_of_arguments,
1368                                        Label *retaddr) {
1369   call_VM_leaf_base1(entry_point, number_of_arguments, 0, ret_type_integral, retaddr);
1370 }
1371 
1372 void MacroAssembler::call_VM_leaf_base1(address entry_point,
1373                                         int number_of_gp_arguments,
1374                                         int number_of_fp_arguments,
1375                                         ret_type type,
1376                                         Label *retaddr) {
1377   Label E, L;
1378 
1379   stp(rscratch1, rmethod, Address(pre(sp, -2 * wordSize)));
1380 
1381   // We add 1 to number_of_arguments because the thread in arg0 is
1382   // not counted
1383   mov(rscratch1, entry_point);
1384   blrt(rscratch1, number_of_gp_arguments + 1, number_of_fp_arguments, type);
1385   if (retaddr)
1386     bind(*retaddr);
1387 
1388   ldp(rscratch1, rmethod, Address(post(sp, 2 * wordSize)));
1389   maybe_isb();
1390 }
1391 
1392 void MacroAssembler::call_VM_leaf(address entry_point, int number_of_arguments) {
1393   call_VM_leaf_base(entry_point, number_of_arguments);
1394 }
1395 
1396 void MacroAssembler::call_VM_leaf(address entry_point, Register arg_0) {
1397   pass_arg0(this, arg_0);
1398   call_VM_leaf_base(entry_point, 1);
1399 }
1400 
1401 void MacroAssembler::call_VM_leaf(address entry_point, Register arg_0, Register arg_1) {
1402   pass_arg0(this, arg_0);
1403   pass_arg1(this, arg_1);
1404   call_VM_leaf_base(entry_point, 2);
1405 }
1406 
1407 void MacroAssembler::call_VM_leaf(address entry_point, Register arg_0,
1408                                   Register arg_1, Register arg_2) {
1409   pass_arg0(this, arg_0);
1410   pass_arg1(this, arg_1);
1411   pass_arg2(this, arg_2);
1412   call_VM_leaf_base(entry_point, 3);
1413 }
1414 
1415 void MacroAssembler::super_call_VM_leaf(address entry_point, Register arg_0) {
1416   pass_arg0(this, arg_0);
1417   MacroAssembler::call_VM_leaf_base(entry_point, 1);
1418 }
1419 
1420 void MacroAssembler::super_call_VM_leaf(address entry_point, Register arg_0, Register arg_1) {
1421 
1422   assert(arg_0 != c_rarg1, "smashed arg");
1423   pass_arg1(this, arg_1);
1424   pass_arg0(this, arg_0);
1425   MacroAssembler::call_VM_leaf_base(entry_point, 2);
1426 }
1427 
1428 void MacroAssembler::super_call_VM_leaf(address entry_point, Register arg_0, Register arg_1, Register arg_2) {
1429   assert(arg_0 != c_rarg2, "smashed arg");
1430   assert(arg_1 != c_rarg2, "smashed arg");
1431   pass_arg2(this, arg_2);
1432   assert(arg_0 != c_rarg1, "smashed arg");
1433   pass_arg1(this, arg_1);
1434   pass_arg0(this, arg_0);
1435   MacroAssembler::call_VM_leaf_base(entry_point, 3);
1436 }
1437 
1438 void MacroAssembler::super_call_VM_leaf(address entry_point, Register arg_0, Register arg_1, Register arg_2, Register arg_3) {
1439   assert(arg_0 != c_rarg3, "smashed arg");
1440   assert(arg_1 != c_rarg3, "smashed arg");
1441   assert(arg_2 != c_rarg3, "smashed arg");
1442   pass_arg3(this, arg_3);
1443   assert(arg_0 != c_rarg2, "smashed arg");
1444   assert(arg_1 != c_rarg2, "smashed arg");
1445   pass_arg2(this, arg_2);
1446   assert(arg_0 != c_rarg1, "smashed arg");
1447   pass_arg1(this, arg_1);
1448   pass_arg0(this, arg_0);
1449   MacroAssembler::call_VM_leaf_base(entry_point, 4);
1450 }
1451 
1452 void MacroAssembler::null_check(Register reg, int offset) {
1453   if (needs_explicit_null_check(offset)) {
1454     // provoke OS NULL exception if reg = NULL by
1455     // accessing M[reg] w/o changing any registers
1456     // NOTE: this is plenty to provoke a segv
1457     ldr(zr, Address(reg));
1458   } else {
1459     // nothing to do, (later) access of M[reg + offset]
1460     // will provoke OS NULL exception if reg = NULL
1461   }
1462 }
1463 
1464 // MacroAssembler protected routines needed to implement
1465 // public methods
1466 
1467 void MacroAssembler::mov(Register r, Address dest) {
1468   code_section()->relocate(pc(), dest.rspec());
1469   u_int64_t imm64 = (u_int64_t)dest.target();
1470   movptr(r, imm64);
1471 }
1472 
1473 // Move a constant pointer into r.  In AArch64 mode the virtual
1474 // address space is 48 bits in size, so we only need three
1475 // instructions to create a patchable instruction sequence that can
1476 // reach anywhere.
1477 void MacroAssembler::movptr(Register r, uintptr_t imm64) {
1478 #ifndef PRODUCT
1479   {
1480     char buffer[64];
1481     snprintf(buffer, sizeof(buffer), "0x%"PRIX64, imm64);
1482     block_comment(buffer);
1483   }
1484 #endif
1485   assert(imm64 < (1ul << 48), "48-bit overflow in address constant");
1486   movz(r, imm64 & 0xffff);
1487   imm64 >>= 16;
1488   movk(r, imm64 & 0xffff, 16);
1489   imm64 >>= 16;
1490   movk(r, imm64 & 0xffff, 32);
1491 }
1492 
1493 // Macro to mov replicated immediate to vector register.
1494 //  Vd will get the following values for different arrangements in T
1495 //   imm32 == hex 000000gh  T8B:  Vd = ghghghghghghghgh
1496 //   imm32 == hex 000000gh  T16B: Vd = ghghghghghghghghghghghghghghghgh
1497 //   imm32 == hex 0000efgh  T4H:  Vd = efghefghefghefgh
1498 //   imm32 == hex 0000efgh  T8H:  Vd = efghefghefghefghefghefghefghefgh
1499 //   imm32 == hex abcdefgh  T2S:  Vd = abcdefghabcdefgh
1500 //   imm32 == hex abcdefgh  T4S:  Vd = abcdefghabcdefghabcdefghabcdefgh
1501 //   T1D/T2D: invalid
1502 void MacroAssembler::mov(FloatRegister Vd, SIMD_Arrangement T, u_int32_t imm32) {
1503   assert(T != T1D && T != T2D, "invalid arrangement");
1504   if (T == T8B || T == T16B) {
1505     assert((imm32 & ~0xff) == 0, "extraneous bits in unsigned imm32 (T8B/T16B)");
1506     movi(Vd, T, imm32 & 0xff, 0);
1507     return;
1508   }
1509   u_int32_t nimm32 = ~imm32;
1510   if (T == T4H || T == T8H) {
1511     assert((imm32  & ~0xffff) == 0, "extraneous bits in unsigned imm32 (T4H/T8H)");
1512     imm32 &= 0xffff;
1513     nimm32 &= 0xffff;
1514   }
1515   u_int32_t x = imm32;
1516   int movi_cnt = 0;
1517   int movn_cnt = 0;
1518   while (x) { if (x & 0xff) movi_cnt++; x >>= 8; }
1519   x = nimm32;
1520   while (x) { if (x & 0xff) movn_cnt++; x >>= 8; }
1521   if (movn_cnt < movi_cnt) imm32 = nimm32;
1522   unsigned lsl = 0;
1523   while (imm32 && (imm32 & 0xff) == 0) { lsl += 8; imm32 >>= 8; }
1524   if (movn_cnt < movi_cnt)
1525     mvni(Vd, T, imm32 & 0xff, lsl);
1526   else
1527     movi(Vd, T, imm32 & 0xff, lsl);
1528   imm32 >>= 8; lsl += 8;
1529   while (imm32) {
1530     while ((imm32 & 0xff) == 0) { lsl += 8; imm32 >>= 8; }
1531     if (movn_cnt < movi_cnt)
1532       bici(Vd, T, imm32 & 0xff, lsl);
1533     else
1534       orri(Vd, T, imm32 & 0xff, lsl);
1535     lsl += 8; imm32 >>= 8;
1536   }
1537 }
1538 
1539 void MacroAssembler::mov_immediate64(Register dst, u_int64_t imm64)
1540 {
1541 #ifndef PRODUCT
1542   {
1543     char buffer[64];
1544     snprintf(buffer, sizeof(buffer), "0x%"PRIX64, imm64);
1545     block_comment(buffer);
1546   }
1547 #endif
1548   if (operand_valid_for_logical_immediate(false, imm64)) {
1549     orr(dst, zr, imm64);
1550   } else {
1551     // we can use a combination of MOVZ or MOVN with
1552     // MOVK to build up the constant
1553     u_int64_t imm_h[4];
1554     int zero_count = 0;
1555     int neg_count = 0;
1556     int i;
1557     for (i = 0; i < 4; i++) {
1558       imm_h[i] = ((imm64 >> (i * 16)) & 0xffffL);
1559       if (imm_h[i] == 0) {
1560         zero_count++;
1561       } else if (imm_h[i] == 0xffffL) {
1562         neg_count++;
1563       }
1564     }
1565     if (zero_count == 4) {
1566       // one MOVZ will do
1567       movz(dst, 0);
1568     } else if (neg_count == 4) {
1569       // one MOVN will do
1570       movn(dst, 0);
1571     } else if (zero_count == 3) {
1572       for (i = 0; i < 4; i++) {
1573         if (imm_h[i] != 0L) {
1574           movz(dst, (u_int32_t)imm_h[i], (i << 4));
1575           break;
1576         }
1577       }
1578     } else if (neg_count == 3) {
1579       // one MOVN will do
1580       for (int i = 0; i < 4; i++) {
1581         if (imm_h[i] != 0xffffL) {
1582           movn(dst, (u_int32_t)imm_h[i] ^ 0xffffL, (i << 4));
1583           break;
1584         }
1585       }
1586     } else if (zero_count == 2) {
1587       // one MOVZ and one MOVK will do
1588       for (i = 0; i < 3; i++) {
1589         if (imm_h[i] != 0L) {
1590           movz(dst, (u_int32_t)imm_h[i], (i << 4));
1591           i++;
1592           break;
1593         }
1594       }
1595       for (;i < 4; i++) {
1596         if (imm_h[i] != 0L) {
1597           movk(dst, (u_int32_t)imm_h[i], (i << 4));
1598         }
1599       }
1600     } else if (neg_count == 2) {
1601       // one MOVN and one MOVK will do
1602       for (i = 0; i < 4; i++) {
1603         if (imm_h[i] != 0xffffL) {
1604           movn(dst, (u_int32_t)imm_h[i] ^ 0xffffL, (i << 4));
1605           i++;
1606           break;
1607         }
1608       }
1609       for (;i < 4; i++) {
1610         if (imm_h[i] != 0xffffL) {
1611           movk(dst, (u_int32_t)imm_h[i], (i << 4));
1612         }
1613       }
1614     } else if (zero_count == 1) {
1615       // one MOVZ and two MOVKs will do
1616       for (i = 0; i < 4; i++) {
1617         if (imm_h[i] != 0L) {
1618           movz(dst, (u_int32_t)imm_h[i], (i << 4));
1619           i++;
1620           break;
1621         }
1622       }
1623       for (;i < 4; i++) {
1624         if (imm_h[i] != 0x0L) {
1625           movk(dst, (u_int32_t)imm_h[i], (i << 4));
1626         }
1627       }
1628     } else if (neg_count == 1) {
1629       // one MOVN and two MOVKs will do
1630       for (i = 0; i < 4; i++) {
1631         if (imm_h[i] != 0xffffL) {
1632           movn(dst, (u_int32_t)imm_h[i] ^ 0xffffL, (i << 4));
1633           i++;
1634           break;
1635         }
1636       }
1637       for (;i < 4; i++) {
1638         if (imm_h[i] != 0xffffL) {
1639           movk(dst, (u_int32_t)imm_h[i], (i << 4));
1640         }
1641       }
1642     } else {
1643       // use a MOVZ and 3 MOVKs (makes it easier to debug)
1644       movz(dst, (u_int32_t)imm_h[0], 0);
1645       for (i = 1; i < 4; i++) {
1646         movk(dst, (u_int32_t)imm_h[i], (i << 4));
1647       }
1648     }
1649   }
1650 }
1651 
1652 void MacroAssembler::mov_immediate32(Register dst, u_int32_t imm32)
1653 {
1654 #ifndef PRODUCT
1655     {
1656       char buffer[64];
1657       snprintf(buffer, sizeof(buffer), "0x%"PRIX32, imm32);
1658       block_comment(buffer);
1659     }
1660 #endif
1661   if (operand_valid_for_logical_immediate(true, imm32)) {
1662     orrw(dst, zr, imm32);
1663   } else {
1664     // we can use MOVZ, MOVN or two calls to MOVK to build up the
1665     // constant
1666     u_int32_t imm_h[2];
1667     imm_h[0] = imm32 & 0xffff;
1668     imm_h[1] = ((imm32 >> 16) & 0xffff);
1669     if (imm_h[0] == 0) {
1670       movzw(dst, imm_h[1], 16);
1671     } else if (imm_h[0] == 0xffff) {
1672       movnw(dst, imm_h[1] ^ 0xffff, 16);
1673     } else if (imm_h[1] == 0) {
1674       movzw(dst, imm_h[0], 0);
1675     } else if (imm_h[1] == 0xffff) {
1676       movnw(dst, imm_h[0] ^ 0xffff, 0);
1677     } else {
1678       // use a MOVZ and MOVK (makes it easier to debug)
1679       movzw(dst, imm_h[0], 0);
1680       movkw(dst, imm_h[1], 16);
1681     }
1682   }
1683 }
1684 
1685 // Form an address from base + offset in Rd.  Rd may or may
1686 // not actually be used: you must use the Address that is returned.
1687 // It is up to you to ensure that the shift provided matches the size
1688 // of your data.
1689 Address MacroAssembler::form_address(Register Rd, Register base, long byte_offset, int shift) {
1690   if (Address::offset_ok_for_immed(byte_offset, shift))
1691     // It fits; no need for any heroics
1692     return Address(base, byte_offset);
1693 
1694   // Don't do anything clever with negative or misaligned offsets
1695   unsigned mask = (1 << shift) - 1;
1696   if (byte_offset < 0 || byte_offset & mask) {
1697     mov(Rd, byte_offset);
1698     add(Rd, base, Rd);
1699     return Address(Rd);
1700   }
1701 
1702   // See if we can do this with two 12-bit offsets
1703   {
1704     unsigned long word_offset = byte_offset >> shift;
1705     unsigned long masked_offset = word_offset & 0xfff000;
1706     if (Address::offset_ok_for_immed(word_offset - masked_offset)
1707         && Assembler::operand_valid_for_add_sub_immediate(masked_offset << shift)) {
1708       add(Rd, base, masked_offset << shift);
1709       word_offset -= masked_offset;
1710       return Address(Rd, word_offset << shift);
1711     }
1712   }
1713 
1714   // Do it the hard way
1715   mov(Rd, byte_offset);
1716   add(Rd, base, Rd);
1717   return Address(Rd);
1718 }
1719 
1720 void MacroAssembler::atomic_incw(Register counter_addr, Register tmp, Register tmp2) {
1721   if (UseLSE) {
1722     mov(tmp, 1);
1723     ldadd(Assembler::word, tmp, zr, counter_addr);
1724     return;
1725   }
1726   Label retry_load;
1727   if ((VM_Version::features() & VM_Version::CPU_STXR_PREFETCH))
1728     prfm(Address(counter_addr), PSTL1STRM);
1729   bind(retry_load);
1730   // flush and load exclusive from the memory location
1731   ldxrw(tmp, counter_addr);
1732   addw(tmp, tmp, 1);
1733   // if we store+flush with no intervening write tmp wil be zero
1734   stxrw(tmp2, tmp, counter_addr);
1735   cbnzw(tmp2, retry_load);
1736 }
1737 
1738 
1739 int MacroAssembler::corrected_idivl(Register result, Register ra, Register rb,
1740                                     bool want_remainder, Register scratch)
1741 {
1742   // Full implementation of Java idiv and irem.  The function
1743   // returns the (pc) offset of the div instruction - may be needed
1744   // for implicit exceptions.
1745   //
1746   // constraint : ra/rb =/= scratch
1747   //         normal case
1748   //
1749   // input : ra: dividend
1750   //         rb: divisor
1751   //
1752   // result: either
1753   //         quotient  (= ra idiv rb)
1754   //         remainder (= ra irem rb)
1755 
1756   assert(ra != scratch && rb != scratch, "reg cannot be scratch");
1757 
1758   int idivl_offset = offset();
1759   if (! want_remainder) {
1760     sdivw(result, ra, rb);
1761   } else {
1762     sdivw(scratch, ra, rb);
1763     Assembler::msubw(result, scratch, rb, ra);
1764   }
1765 
1766   return idivl_offset;
1767 }
1768 
1769 int MacroAssembler::corrected_idivq(Register result, Register ra, Register rb,
1770                                     bool want_remainder, Register scratch)
1771 {
1772   // Full implementation of Java ldiv and lrem.  The function
1773   // returns the (pc) offset of the div instruction - may be needed
1774   // for implicit exceptions.
1775   //
1776   // constraint : ra/rb =/= scratch
1777   //         normal case
1778   //
1779   // input : ra: dividend
1780   //         rb: divisor
1781   //
1782   // result: either
1783   //         quotient  (= ra idiv rb)
1784   //         remainder (= ra irem rb)
1785 
1786   assert(ra != scratch && rb != scratch, "reg cannot be scratch");
1787 
1788   int idivq_offset = offset();
1789   if (! want_remainder) {
1790     sdiv(result, ra, rb);
1791   } else {
1792     sdiv(scratch, ra, rb);
1793     Assembler::msub(result, scratch, rb, ra);
1794   }
1795 
1796   return idivq_offset;
1797 }
1798 
1799 void MacroAssembler::membar(Membar_mask_bits order_constraint) {
1800   address prev = pc() - NativeMembar::instruction_size;
1801   address last = code()->last_insn();
1802   if (last != NULL && nativeInstruction_at(last)->is_Membar() && prev == last) {
1803     NativeMembar *bar = NativeMembar_at(prev);
1804     // We are merging two memory barrier instructions.  On AArch64 we
1805     // can do this simply by ORing them together.
1806     bar->set_kind(bar->get_kind() | order_constraint);
1807     BLOCK_COMMENT("merged membar");
1808   } else {
1809     code()->set_last_insn(pc());
1810     dmb(Assembler::barrier(order_constraint));
1811   }
1812 }
1813 
1814 bool MacroAssembler::try_merge_ldst(Register rt, const Address &adr, size_t size_in_bytes, bool is_store) {
1815   if (ldst_can_merge(rt, adr, size_in_bytes, is_store)) {
1816     merge_ldst(rt, adr, size_in_bytes, is_store);
1817     code()->clear_last_insn();
1818     return true;
1819   } else {
1820     assert(size_in_bytes == 8 || size_in_bytes == 4, "only 8 bytes or 4 bytes load/store is supported.");
1821     const unsigned mask = size_in_bytes - 1;
1822     if (adr.getMode() == Address::base_plus_offset &&
1823         (adr.offset() & mask) == 0) { // only supports base_plus_offset.
1824       code()->set_last_insn(pc());
1825     }
1826     return false;
1827   }
1828 }
1829 
1830 void MacroAssembler::ldr(Register Rx, const Address &adr) {
1831   // We always try to merge two adjacent loads into one ldp.
1832   if (!try_merge_ldst(Rx, adr, 8, false)) {
1833     Assembler::ldr(Rx, adr);
1834   }
1835 }
1836 
1837 void MacroAssembler::ldrw(Register Rw, const Address &adr) {
1838   // We always try to merge two adjacent loads into one ldp.
1839   if (!try_merge_ldst(Rw, adr, 4, false)) {
1840     Assembler::ldrw(Rw, adr);
1841   }
1842 }
1843 
1844 void MacroAssembler::str(Register Rx, const Address &adr) {
1845   // We always try to merge two adjacent stores into one stp.
1846   if (!try_merge_ldst(Rx, adr, 8, true)) {
1847     Assembler::str(Rx, adr);
1848   }
1849 }
1850 
1851 void MacroAssembler::strw(Register Rw, const Address &adr) {
1852   // We always try to merge two adjacent stores into one stp.
1853   if (!try_merge_ldst(Rw, adr, 4, true)) {
1854     Assembler::strw(Rw, adr);
1855   }
1856 }
1857 
1858 // MacroAssembler routines found actually to be needed
1859 
1860 void MacroAssembler::push(Register src)
1861 {
1862   str(src, Address(pre(esp, -1 * wordSize)));
1863 }
1864 
1865 void MacroAssembler::pop(Register dst)
1866 {
1867   ldr(dst, Address(post(esp, 1 * wordSize)));
1868 }
1869 
1870 // Note: load_unsigned_short used to be called load_unsigned_word.
1871 int MacroAssembler::load_unsigned_short(Register dst, Address src) {
1872   int off = offset();
1873   ldrh(dst, src);
1874   return off;
1875 }
1876 
1877 int MacroAssembler::load_unsigned_byte(Register dst, Address src) {
1878   int off = offset();
1879   ldrb(dst, src);
1880   return off;
1881 }
1882 
1883 int MacroAssembler::load_signed_short(Register dst, Address src) {
1884   int off = offset();
1885   ldrsh(dst, src);
1886   return off;
1887 }
1888 
1889 int MacroAssembler::load_signed_byte(Register dst, Address src) {
1890   int off = offset();
1891   ldrsb(dst, src);
1892   return off;
1893 }
1894 
1895 int MacroAssembler::load_signed_short32(Register dst, Address src) {
1896   int off = offset();
1897   ldrshw(dst, src);
1898   return off;
1899 }
1900 
1901 int MacroAssembler::load_signed_byte32(Register dst, Address src) {
1902   int off = offset();
1903   ldrsbw(dst, src);
1904   return off;
1905 }
1906 
1907 void MacroAssembler::load_sized_value(Register dst, Address src, size_t size_in_bytes, bool is_signed, Register dst2) {
1908   switch (size_in_bytes) {
1909   case  8:  ldr(dst, src); break;
1910   case  4:  ldrw(dst, src); break;
1911   case  2:  is_signed ? load_signed_short(dst, src) : load_unsigned_short(dst, src); break;
1912   case  1:  is_signed ? load_signed_byte( dst, src) : load_unsigned_byte( dst, src); break;
1913   default:  ShouldNotReachHere();
1914   }
1915 }
1916 
1917 void MacroAssembler::store_sized_value(Address dst, Register src, size_t size_in_bytes, Register src2) {
1918   switch (size_in_bytes) {
1919   case  8:  str(src, dst); break;
1920   case  4:  strw(src, dst); break;
1921   case  2:  strh(src, dst); break;
1922   case  1:  strb(src, dst); break;
1923   default:  ShouldNotReachHere();
1924   }
1925 }
1926 
1927 void MacroAssembler::decrementw(Register reg, int value)
1928 {
1929   if (value < 0)  { incrementw(reg, -value);      return; }
1930   if (value == 0) {                               return; }
1931   if (value < (1 << 12)) { subw(reg, reg, value); return; }
1932   /* else */ {
1933     guarantee(reg != rscratch2, "invalid dst for register decrement");
1934     movw(rscratch2, (unsigned)value);
1935     subw(reg, reg, rscratch2);
1936   }
1937 }
1938 
1939 void MacroAssembler::decrement(Register reg, int value)
1940 {
1941   if (value < 0)  { increment(reg, -value);      return; }
1942   if (value == 0) {                              return; }
1943   if (value < (1 << 12)) { sub(reg, reg, value); return; }
1944   /* else */ {
1945     assert(reg != rscratch2, "invalid dst for register decrement");
1946     mov(rscratch2, (unsigned long)value);
1947     sub(reg, reg, rscratch2);
1948   }
1949 }
1950 
1951 void MacroAssembler::decrementw(Address dst, int value)
1952 {
1953   assert(!dst.uses(rscratch1), "invalid dst for address decrement");
1954   if (dst.getMode() == Address::literal) {
1955     assert(abs(value) < (1 << 12), "invalid value and address mode combination");
1956     lea(rscratch2, dst);
1957     dst = Address(rscratch2);
1958   }
1959   ldrw(rscratch1, dst);
1960   decrementw(rscratch1, value);
1961   strw(rscratch1, dst);
1962 }
1963 
1964 void MacroAssembler::decrement(Address dst, int value)
1965 {
1966   assert(!dst.uses(rscratch1), "invalid address for decrement");
1967   if (dst.getMode() == Address::literal) {
1968     assert(abs(value) < (1 << 12), "invalid value and address mode combination");
1969     lea(rscratch2, dst);
1970     dst = Address(rscratch2);
1971   }
1972   ldr(rscratch1, dst);
1973   decrement(rscratch1, value);
1974   str(rscratch1, dst);
1975 }
1976 
1977 void MacroAssembler::incrementw(Register reg, int value)
1978 {
1979   if (value < 0)  { decrementw(reg, -value);      return; }
1980   if (value == 0) {                               return; }
1981   if (value < (1 << 12)) { addw(reg, reg, value); return; }
1982   /* else */ {
1983     assert(reg != rscratch2, "invalid dst for register increment");
1984     movw(rscratch2, (unsigned)value);
1985     addw(reg, reg, rscratch2);
1986   }
1987 }
1988 
1989 void MacroAssembler::increment(Register reg, int value)
1990 {
1991   if (value < 0)  { decrement(reg, -value);      return; }
1992   if (value == 0) {                              return; }
1993   if (value < (1 << 12)) { add(reg, reg, value); return; }
1994   /* else */ {
1995     assert(reg != rscratch2, "invalid dst for register increment");
1996     movw(rscratch2, (unsigned)value);
1997     add(reg, reg, rscratch2);
1998   }
1999 }
2000 
2001 void MacroAssembler::incrementw(Address dst, int value)
2002 {
2003   assert(!dst.uses(rscratch1), "invalid dst for address increment");
2004   if (dst.getMode() == Address::literal) {
2005     assert(abs(value) < (1 << 12), "invalid value and address mode combination");
2006     lea(rscratch2, dst);
2007     dst = Address(rscratch2);
2008   }
2009   ldrw(rscratch1, dst);
2010   incrementw(rscratch1, value);
2011   strw(rscratch1, dst);
2012 }
2013 
2014 void MacroAssembler::increment(Address dst, int value)
2015 {
2016   assert(!dst.uses(rscratch1), "invalid dst for address increment");
2017   if (dst.getMode() == Address::literal) {
2018     assert(abs(value) < (1 << 12), "invalid value and address mode combination");
2019     lea(rscratch2, dst);
2020     dst = Address(rscratch2);
2021   }
2022   ldr(rscratch1, dst);
2023   increment(rscratch1, value);
2024   str(rscratch1, dst);
2025 }
2026 
2027 
2028 void MacroAssembler::pusha() {
2029   push(0x7fffffff, sp);
2030 }
2031 
2032 void MacroAssembler::popa() {
2033   pop(0x7fffffff, sp);
2034 }
2035 
2036 // Push lots of registers in the bit set supplied.  Don't push sp.
2037 // Return the number of words pushed
2038 int MacroAssembler::push(unsigned int bitset, Register stack) {
2039   int words_pushed = 0;
2040 
2041   // Scan bitset to accumulate register pairs
2042   unsigned char regs[32];
2043   int count = 0;
2044   for (int reg = 0; reg <= 30; reg++) {
2045     if (1 & bitset)
2046       regs[count++] = reg;
2047     bitset >>= 1;
2048   }
2049   regs[count++] = zr->encoding_nocheck();
2050   count &= ~1;  // Only push an even nuber of regs
2051 
2052   if (count) {
2053     stp(as_Register(regs[0]), as_Register(regs[1]),
2054        Address(pre(stack, -count * wordSize)));
2055     words_pushed += 2;
2056   }
2057   for (int i = 2; i < count; i += 2) {
2058     stp(as_Register(regs[i]), as_Register(regs[i+1]),
2059        Address(stack, i * wordSize));
2060     words_pushed += 2;
2061   }
2062 
2063   assert(words_pushed == count, "oops, pushed != count");
2064 
2065   return count;
2066 }
2067 
2068 int MacroAssembler::pop(unsigned int bitset, Register stack) {
2069   int words_pushed = 0;
2070 
2071   // Scan bitset to accumulate register pairs
2072   unsigned char regs[32];
2073   int count = 0;
2074   for (int reg = 0; reg <= 30; reg++) {
2075     if (1 & bitset)
2076       regs[count++] = reg;
2077     bitset >>= 1;
2078   }
2079   regs[count++] = zr->encoding_nocheck();
2080   count &= ~1;
2081 
2082   for (int i = 2; i < count; i += 2) {
2083     ldp(as_Register(regs[i]), as_Register(regs[i+1]),
2084        Address(stack, i * wordSize));
2085     words_pushed += 2;
2086   }
2087   if (count) {
2088     ldp(as_Register(regs[0]), as_Register(regs[1]),
2089        Address(post(stack, count * wordSize)));
2090     words_pushed += 2;
2091   }
2092 
2093   assert(words_pushed == count, "oops, pushed != count");
2094 
2095   return count;
2096 }
2097 #ifdef ASSERT
2098 void MacroAssembler::verify_heapbase(const char* msg) {
2099 #if 0
2100   assert (UseCompressedOops || UseCompressedClassPointers, "should be compressed");
2101   assert (Universe::heap() != NULL, "java heap should be initialized");
2102   if (CheckCompressedOops) {
2103     Label ok;
2104     push(1 << rscratch1->encoding(), sp); // cmpptr trashes rscratch1
2105     cmpptr(rheapbase, ExternalAddress((address)Universe::narrow_ptrs_base_addr()));
2106     br(Assembler::EQ, ok);
2107     stop(msg);
2108     bind(ok);
2109     pop(1 << rscratch1->encoding(), sp);
2110   }
2111 #endif
2112 }
2113 #endif
2114 
2115 void MacroAssembler::resolve_jobject(Register value, Register thread, Register tmp) {
2116   Label done, not_weak;
2117   cbz(value, done);           // Use NULL as-is.
2118 
2119   STATIC_ASSERT(JNIHandles::weak_tag_mask == 1u);
2120   tbz(r0, 0, not_weak);    // Test for jweak tag.
2121 
2122   // Resolve jweak.
2123   access_load_at(T_OBJECT, IN_NATIVE | ON_PHANTOM_OOP_REF, value,
2124                  Address(value, -JNIHandles::weak_tag_value), tmp, thread);
2125   verify_oop(value);
2126   b(done);
2127 
2128   bind(not_weak);
2129   // Resolve (untagged) jobject.
2130   access_load_at(T_OBJECT, IN_NATIVE, value, Address(value, 0), tmp, thread);
2131   verify_oop(value);
2132   bind(done);
2133 }
2134 
2135 void MacroAssembler::stop(const char* msg) {
2136   address ip = pc();
2137   pusha();
2138   mov(c_rarg0, (address)msg);
2139   mov(c_rarg1, (address)ip);
2140   mov(c_rarg2, sp);
2141   mov(c_rarg3, CAST_FROM_FN_PTR(address, MacroAssembler::debug64));
2142   // call(c_rarg3);
2143   blrt(c_rarg3, 3, 0, 1);
2144   hlt(0);
2145 }
2146 
2147 void MacroAssembler::unimplemented(const char* what) {
2148   const char* buf = NULL;
2149   {
2150     ResourceMark rm;
2151     stringStream ss;
2152     ss.print("unimplemented: %s", what);
2153     buf = code_string(ss.as_string());
2154   }
2155   stop(buf);
2156 }
2157 
2158 // If a constant does not fit in an immediate field, generate some
2159 // number of MOV instructions and then perform the operation.
2160 void MacroAssembler::wrap_add_sub_imm_insn(Register Rd, Register Rn, unsigned imm,
2161                                            add_sub_imm_insn insn1,
2162                                            add_sub_reg_insn insn2) {
2163   assert(Rd != zr, "Rd = zr and not setting flags?");
2164   if (operand_valid_for_add_sub_immediate((int)imm)) {
2165     (this->*insn1)(Rd, Rn, imm);
2166   } else {
2167     if (uabs(imm) < (1 << 24)) {
2168        (this->*insn1)(Rd, Rn, imm & -(1 << 12));
2169        (this->*insn1)(Rd, Rd, imm & ((1 << 12)-1));
2170     } else {
2171        assert_different_registers(Rd, Rn);
2172        mov(Rd, (uint64_t)imm);
2173        (this->*insn2)(Rd, Rn, Rd, LSL, 0);
2174     }
2175   }
2176 }
2177 
2178 // Seperate vsn which sets the flags. Optimisations are more restricted
2179 // because we must set the flags correctly.
2180 void MacroAssembler::wrap_adds_subs_imm_insn(Register Rd, Register Rn, unsigned imm,
2181                                            add_sub_imm_insn insn1,
2182                                            add_sub_reg_insn insn2) {
2183   if (operand_valid_for_add_sub_immediate((int)imm)) {
2184     (this->*insn1)(Rd, Rn, imm);
2185   } else {
2186     assert_different_registers(Rd, Rn);
2187     assert(Rd != zr, "overflow in immediate operand");
2188     mov(Rd, (uint64_t)imm);
2189     (this->*insn2)(Rd, Rn, Rd, LSL, 0);
2190   }
2191 }
2192 
2193 
2194 void MacroAssembler::add(Register Rd, Register Rn, RegisterOrConstant increment) {
2195   if (increment.is_register()) {
2196     add(Rd, Rn, increment.as_register());
2197   } else {
2198     add(Rd, Rn, increment.as_constant());
2199   }
2200 }
2201 
2202 void MacroAssembler::addw(Register Rd, Register Rn, RegisterOrConstant increment) {
2203   if (increment.is_register()) {
2204     addw(Rd, Rn, increment.as_register());
2205   } else {
2206     addw(Rd, Rn, increment.as_constant());
2207   }
2208 }
2209 
2210 void MacroAssembler::sub(Register Rd, Register Rn, RegisterOrConstant decrement) {
2211   if (decrement.is_register()) {
2212     sub(Rd, Rn, decrement.as_register());
2213   } else {
2214     sub(Rd, Rn, decrement.as_constant());
2215   }
2216 }
2217 
2218 void MacroAssembler::subw(Register Rd, Register Rn, RegisterOrConstant decrement) {
2219   if (decrement.is_register()) {
2220     subw(Rd, Rn, decrement.as_register());
2221   } else {
2222     subw(Rd, Rn, decrement.as_constant());
2223   }
2224 }
2225 
2226 void MacroAssembler::reinit_heapbase()
2227 {
2228   if (UseCompressedOops) {
2229     if (Universe::is_fully_initialized()) {
2230       mov(rheapbase, Universe::narrow_ptrs_base());
2231     } else {
2232       lea(rheapbase, ExternalAddress((address)Universe::narrow_ptrs_base_addr()));
2233       ldr(rheapbase, Address(rheapbase));
2234     }
2235   }
2236 }
2237 
2238 // this simulates the behaviour of the x86 cmpxchg instruction using a
2239 // load linked/store conditional pair. we use the acquire/release
2240 // versions of these instructions so that we flush pending writes as
2241 // per Java semantics.
2242 
2243 // n.b the x86 version assumes the old value to be compared against is
2244 // in rax and updates rax with the value located in memory if the
2245 // cmpxchg fails. we supply a register for the old value explicitly
2246 
2247 // the aarch64 load linked/store conditional instructions do not
2248 // accept an offset. so, unlike x86, we must provide a plain register
2249 // to identify the memory word to be compared/exchanged rather than a
2250 // register+offset Address.
2251 
2252 void MacroAssembler::cmpxchgptr(Register oldv, Register newv, Register addr, Register tmp,
2253                                 Label &succeed, Label *fail) {
2254   // oldv holds comparison value
2255   // newv holds value to write in exchange
2256   // addr identifies memory word to compare against/update
2257   if (UseLSE) {
2258     mov(tmp, oldv);
2259     casal(Assembler::xword, oldv, newv, addr);
2260     cmp(tmp, oldv);
2261     br(Assembler::EQ, succeed);
2262     membar(AnyAny);
2263   } else {
2264     Label retry_load, nope;
2265     if ((VM_Version::features() & VM_Version::CPU_STXR_PREFETCH))
2266       prfm(Address(addr), PSTL1STRM);
2267     bind(retry_load);
2268     // flush and load exclusive from the memory location
2269     // and fail if it is not what we expect
2270     ldaxr(tmp, addr);
2271     cmp(tmp, oldv);
2272     br(Assembler::NE, nope);
2273     // if we store+flush with no intervening write tmp wil be zero
2274     stlxr(tmp, newv, addr);
2275     cbzw(tmp, succeed);
2276     // retry so we only ever return after a load fails to compare
2277     // ensures we don't return a stale value after a failed write.
2278     b(retry_load);
2279     // if the memory word differs we return it in oldv and signal a fail
2280     bind(nope);
2281     membar(AnyAny);
2282     mov(oldv, tmp);
2283   }
2284   if (fail)
2285     b(*fail);
2286 }
2287 
2288 void MacroAssembler::cmpxchg_obj_header(Register oldv, Register newv, Register obj, Register tmp,
2289                                         Label &succeed, Label *fail) {
2290   assert(oopDesc::mark_offset_in_bytes() == 0, "assumption");
2291   cmpxchgptr(oldv, newv, obj, tmp, succeed, fail);
2292 }
2293 
2294 void MacroAssembler::cmpxchgw(Register oldv, Register newv, Register addr, Register tmp,
2295                                 Label &succeed, Label *fail) {
2296   // oldv holds comparison value
2297   // newv holds value to write in exchange
2298   // addr identifies memory word to compare against/update
2299   // tmp returns 0/1 for success/failure
2300   if (UseLSE) {
2301     mov(tmp, oldv);
2302     casal(Assembler::word, oldv, newv, addr);
2303     cmp(tmp, oldv);
2304     br(Assembler::EQ, succeed);
2305     membar(AnyAny);
2306   } else {
2307     Label retry_load, nope;
2308     if ((VM_Version::features() & VM_Version::CPU_STXR_PREFETCH))
2309       prfm(Address(addr), PSTL1STRM);
2310     bind(retry_load);
2311     // flush and load exclusive from the memory location
2312     // and fail if it is not what we expect
2313     ldaxrw(tmp, addr);
2314     cmp(tmp, oldv);
2315     br(Assembler::NE, nope);
2316     // if we store+flush with no intervening write tmp wil be zero
2317     stlxrw(tmp, newv, addr);
2318     cbzw(tmp, succeed);
2319     // retry so we only ever return after a load fails to compare
2320     // ensures we don't return a stale value after a failed write.
2321     b(retry_load);
2322     // if the memory word differs we return it in oldv and signal a fail
2323     bind(nope);
2324     membar(AnyAny);
2325     mov(oldv, tmp);
2326   }
2327   if (fail)
2328     b(*fail);
2329 }
2330 
2331 // A generic CAS; success or failure is in the EQ flag.  A weak CAS
2332 // doesn't retry and may fail spuriously.  If the oldval is wanted,
2333 // Pass a register for the result, otherwise pass noreg.
2334 
2335 // Clobbers rscratch1
2336 void MacroAssembler::cmpxchg(Register addr, Register expected,
2337                              Register new_val,
2338                              enum operand_size size,
2339                              bool acquire, bool release,
2340                              bool weak,
2341                              Register result) {
2342   if (result == noreg)  result = rscratch1;
2343   if (UseLSE) {
2344     mov(result, expected);
2345     lse_cas(result, new_val, addr, size, acquire, release, /*not_pair*/ true);
2346     cmp(result, expected);
2347   } else {
2348     BLOCK_COMMENT("cmpxchg {");
2349     Label retry_load, done;
2350     if ((VM_Version::features() & VM_Version::CPU_STXR_PREFETCH))
2351       prfm(Address(addr), PSTL1STRM);
2352     bind(retry_load);
2353     load_exclusive(result, addr, size, acquire);
2354     if (size == xword)
2355       cmp(result, expected);
2356     else
2357       cmpw(result, expected);
2358     br(Assembler::NE, done);
2359     store_exclusive(rscratch1, new_val, addr, size, release);
2360     if (weak) {
2361       cmpw(rscratch1, 0u);  // If the store fails, return NE to our caller.
2362     } else {
2363       cbnzw(rscratch1, retry_load);
2364     }
2365     bind(done);
2366     BLOCK_COMMENT("} cmpxchg");
2367   }
2368 }
2369 
2370 static bool different(Register a, RegisterOrConstant b, Register c) {
2371   if (b.is_constant())
2372     return a != c;
2373   else
2374     return a != b.as_register() && a != c && b.as_register() != c;
2375 }
2376 
2377 #define ATOMIC_OP(NAME, LDXR, OP, IOP, AOP, STXR, sz)                   \
2378 void MacroAssembler::atomic_##NAME(Register prev, RegisterOrConstant incr, Register addr) { \
2379   if (UseLSE) {                                                         \
2380     prev = prev->is_valid() ? prev : zr;                                \
2381     if (incr.is_register()) {                                           \
2382       AOP(sz, incr.as_register(), prev, addr);                          \
2383     } else {                                                            \
2384       mov(rscratch2, incr.as_constant());                               \
2385       AOP(sz, rscratch2, prev, addr);                                   \
2386     }                                                                   \
2387     return;                                                             \
2388   }                                                                     \
2389   Register result = rscratch2;                                          \
2390   if (prev->is_valid())                                                 \
2391     result = different(prev, incr, addr) ? prev : rscratch2;            \
2392                                                                         \
2393   Label retry_load;                                                     \
2394   if ((VM_Version::features() & VM_Version::CPU_STXR_PREFETCH))         \
2395     prfm(Address(addr), PSTL1STRM);                                     \
2396   bind(retry_load);                                                     \
2397   LDXR(result, addr);                                                   \
2398   OP(rscratch1, result, incr);                                          \
2399   STXR(rscratch2, rscratch1, addr);                                     \
2400   cbnzw(rscratch2, retry_load);                                         \
2401   if (prev->is_valid() && prev != result) {                             \
2402     IOP(prev, rscratch1, incr);                                         \
2403   }                                                                     \
2404 }
2405 
2406 ATOMIC_OP(add, ldxr, add, sub, ldadd, stxr, Assembler::xword)
2407 ATOMIC_OP(addw, ldxrw, addw, subw, ldadd, stxrw, Assembler::word)
2408 ATOMIC_OP(addal, ldaxr, add, sub, ldaddal, stlxr, Assembler::xword)
2409 ATOMIC_OP(addalw, ldaxrw, addw, subw, ldaddal, stlxrw, Assembler::word)
2410 
2411 #undef ATOMIC_OP
2412 
2413 #define ATOMIC_XCHG(OP, AOP, LDXR, STXR, sz)                            \
2414 void MacroAssembler::atomic_##OP(Register prev, Register newv, Register addr) { \
2415   if (UseLSE) {                                                         \
2416     prev = prev->is_valid() ? prev : zr;                                \
2417     AOP(sz, newv, prev, addr);                                          \
2418     return;                                                             \
2419   }                                                                     \
2420   Register result = rscratch2;                                          \
2421   if (prev->is_valid())                                                 \
2422     result = different(prev, newv, addr) ? prev : rscratch2;            \
2423                                                                         \
2424   Label retry_load;                                                     \
2425   if ((VM_Version::features() & VM_Version::CPU_STXR_PREFETCH))         \
2426     prfm(Address(addr), PSTL1STRM);                                     \
2427   bind(retry_load);                                                     \
2428   LDXR(result, addr);                                                   \
2429   STXR(rscratch1, newv, addr);                                          \
2430   cbnzw(rscratch1, retry_load);                                         \
2431   if (prev->is_valid() && prev != result)                               \
2432     mov(prev, result);                                                  \
2433 }
2434 
2435 ATOMIC_XCHG(xchg, swp, ldxr, stxr, Assembler::xword)
2436 ATOMIC_XCHG(xchgw, swp, ldxrw, stxrw, Assembler::word)
2437 ATOMIC_XCHG(xchgal, swpal, ldaxr, stlxr, Assembler::xword)
2438 ATOMIC_XCHG(xchgalw, swpal, ldaxrw, stlxrw, Assembler::word)
2439 
2440 #undef ATOMIC_XCHG
2441 
2442 #ifndef PRODUCT
2443 extern "C" void findpc(intptr_t x);
2444 #endif
2445 
2446 void MacroAssembler::debug64(char* msg, int64_t pc, int64_t regs[])
2447 {
2448   // In order to get locks to work, we need to fake a in_VM state
2449   if (ShowMessageBoxOnError ) {
2450     JavaThread* thread = JavaThread::current();
2451     JavaThreadState saved_state = thread->thread_state();
2452     thread->set_thread_state(_thread_in_vm);
2453 #ifndef PRODUCT
2454     if (CountBytecodes || TraceBytecodes || StopInterpreterAt) {
2455       ttyLocker ttyl;
2456       BytecodeCounter::print();
2457     }
2458 #endif
2459     if (os::message_box(msg, "Execution stopped, print registers?")) {
2460       ttyLocker ttyl;
2461       tty->print_cr(" pc = 0x%016lx", pc);
2462 #ifndef PRODUCT
2463       tty->cr();
2464       findpc(pc);
2465       tty->cr();
2466 #endif
2467       tty->print_cr(" r0 = 0x%016lx", regs[0]);
2468       tty->print_cr(" r1 = 0x%016lx", regs[1]);
2469       tty->print_cr(" r2 = 0x%016lx", regs[2]);
2470       tty->print_cr(" r3 = 0x%016lx", regs[3]);
2471       tty->print_cr(" r4 = 0x%016lx", regs[4]);
2472       tty->print_cr(" r5 = 0x%016lx", regs[5]);
2473       tty->print_cr(" r6 = 0x%016lx", regs[6]);
2474       tty->print_cr(" r7 = 0x%016lx", regs[7]);
2475       tty->print_cr(" r8 = 0x%016lx", regs[8]);
2476       tty->print_cr(" r9 = 0x%016lx", regs[9]);
2477       tty->print_cr("r10 = 0x%016lx", regs[10]);
2478       tty->print_cr("r11 = 0x%016lx", regs[11]);
2479       tty->print_cr("r12 = 0x%016lx", regs[12]);
2480       tty->print_cr("r13 = 0x%016lx", regs[13]);
2481       tty->print_cr("r14 = 0x%016lx", regs[14]);
2482       tty->print_cr("r15 = 0x%016lx", regs[15]);
2483       tty->print_cr("r16 = 0x%016lx", regs[16]);
2484       tty->print_cr("r17 = 0x%016lx", regs[17]);
2485       tty->print_cr("r18 = 0x%016lx", regs[18]);
2486       tty->print_cr("r19 = 0x%016lx", regs[19]);
2487       tty->print_cr("r20 = 0x%016lx", regs[20]);
2488       tty->print_cr("r21 = 0x%016lx", regs[21]);
2489       tty->print_cr("r22 = 0x%016lx", regs[22]);
2490       tty->print_cr("r23 = 0x%016lx", regs[23]);
2491       tty->print_cr("r24 = 0x%016lx", regs[24]);
2492       tty->print_cr("r25 = 0x%016lx", regs[25]);
2493       tty->print_cr("r26 = 0x%016lx", regs[26]);
2494       tty->print_cr("r27 = 0x%016lx", regs[27]);
2495       tty->print_cr("r28 = 0x%016lx", regs[28]);
2496       tty->print_cr("r30 = 0x%016lx", regs[30]);
2497       tty->print_cr("r31 = 0x%016lx", regs[31]);
2498       BREAKPOINT;
2499     }
2500     ThreadStateTransition::transition(thread, _thread_in_vm, saved_state);
2501   } else {
2502     ttyLocker ttyl;
2503     ::tty->print_cr("=============== DEBUG MESSAGE: %s ================\n",
2504                     msg);
2505     assert(false, "DEBUG MESSAGE: %s", msg);
2506   }
2507 }
2508 
2509 #ifdef BUILTIN_SIM
2510 // routine to generate an x86 prolog for a stub function which
2511 // bootstraps into the generated ARM code which directly follows the
2512 // stub
2513 //
2514 // the argument encodes the number of general and fp registers
2515 // passed by the caller and the callng convention (currently just
2516 // the number of general registers and assumes C argument passing)
2517 
2518 extern "C" {
2519 int aarch64_stub_prolog_size();
2520 void aarch64_stub_prolog();
2521 void aarch64_prolog();
2522 }
2523 
2524 void MacroAssembler::c_stub_prolog(int gp_arg_count, int fp_arg_count, int ret_type,
2525                                    address *prolog_ptr)
2526 {
2527   int calltype = (((ret_type & 0x3) << 8) |
2528                   ((fp_arg_count & 0xf) << 4) |
2529                   (gp_arg_count & 0xf));
2530 
2531   // the addresses for the x86 to ARM entry code we need to use
2532   address start = pc();
2533   // printf("start = %lx\n", start);
2534   int byteCount =  aarch64_stub_prolog_size();
2535   // printf("byteCount = %x\n", byteCount);
2536   int instructionCount = (byteCount + 3)/ 4;
2537   // printf("instructionCount = %x\n", instructionCount);
2538   for (int i = 0; i < instructionCount; i++) {
2539     nop();
2540   }
2541 
2542   memcpy(start, (void*)aarch64_stub_prolog, byteCount);
2543 
2544   // write the address of the setup routine and the call format at the
2545   // end of into the copied code
2546   u_int64_t *patch_end = (u_int64_t *)(start + byteCount);
2547   if (prolog_ptr)
2548     patch_end[-2] = (u_int64_t)prolog_ptr;
2549   patch_end[-1] = calltype;
2550 }
2551 #endif
2552 
2553 void MacroAssembler::push_call_clobbered_registers() {
2554   int step = 4 * wordSize;
2555   push(RegSet::range(r0, r18) - RegSet::of(rscratch1, rscratch2), sp);
2556   sub(sp, sp, step);
2557   mov(rscratch1, -step);
2558   // Push v0-v7, v16-v31.
2559   for (int i = 31; i>= 4; i -= 4) {
2560     if (i <= v7->encoding() || i >= v16->encoding())
2561       st1(as_FloatRegister(i-3), as_FloatRegister(i-2), as_FloatRegister(i-1),
2562           as_FloatRegister(i), T1D, Address(post(sp, rscratch1)));
2563   }
2564   st1(as_FloatRegister(0), as_FloatRegister(1), as_FloatRegister(2),
2565       as_FloatRegister(3), T1D, Address(sp));
2566 }
2567 
2568 void MacroAssembler::pop_call_clobbered_registers() {
2569   for (int i = 0; i < 32; i += 4) {
2570     if (i <= v7->encoding() || i >= v16->encoding())
2571       ld1(as_FloatRegister(i), as_FloatRegister(i+1), as_FloatRegister(i+2),
2572           as_FloatRegister(i+3), T1D, Address(post(sp, 4 * wordSize)));
2573   }
2574 
2575   pop(RegSet::range(r0, r18) - RegSet::of(rscratch1, rscratch2), sp);
2576 }
2577 
2578 void MacroAssembler::push_CPU_state(bool save_vectors) {
2579   int step = (save_vectors ? 8 : 4) * wordSize;
2580   push(0x3fffffff, sp);         // integer registers except lr & sp
2581   mov(rscratch1, -step);
2582   sub(sp, sp, step);
2583   for (int i = 28; i >= 4; i -= 4) {
2584     st1(as_FloatRegister(i), as_FloatRegister(i+1), as_FloatRegister(i+2),
2585         as_FloatRegister(i+3), save_vectors ? T2D : T1D, Address(post(sp, rscratch1)));
2586   }
2587   st1(v0, v1, v2, v3, save_vectors ? T2D : T1D, sp);
2588 }
2589 
2590 void MacroAssembler::pop_CPU_state(bool restore_vectors) {
2591   int step = (restore_vectors ? 8 : 4) * wordSize;
2592   for (int i = 0; i <= 28; i += 4)
2593     ld1(as_FloatRegister(i), as_FloatRegister(i+1), as_FloatRegister(i+2),
2594         as_FloatRegister(i+3), restore_vectors ? T2D : T1D, Address(post(sp, step)));
2595   pop(0x3fffffff, sp);         // integer registers except lr & sp
2596 }
2597 
2598 /**
2599  * Helpers for multiply_to_len().
2600  */
2601 void MacroAssembler::add2_with_carry(Register final_dest_hi, Register dest_hi, Register dest_lo,
2602                                      Register src1, Register src2) {
2603   adds(dest_lo, dest_lo, src1);
2604   adc(dest_hi, dest_hi, zr);
2605   adds(dest_lo, dest_lo, src2);
2606   adc(final_dest_hi, dest_hi, zr);
2607 }
2608 
2609 // Generate an address from (r + r1 extend offset).  "size" is the
2610 // size of the operand.  The result may be in rscratch2.
2611 Address MacroAssembler::offsetted_address(Register r, Register r1,
2612                                           Address::extend ext, int offset, int size) {
2613   if (offset || (ext.shift() % size != 0)) {
2614     lea(rscratch2, Address(r, r1, ext));
2615     return Address(rscratch2, offset);
2616   } else {
2617     return Address(r, r1, ext);
2618   }
2619 }
2620 
2621 Address MacroAssembler::spill_address(int size, int offset, Register tmp)
2622 {
2623   assert(offset >= 0, "spill to negative address?");
2624   // Offset reachable ?
2625   //   Not aligned - 9 bits signed offset
2626   //   Aligned - 12 bits unsigned offset shifted
2627   Register base = sp;
2628   if ((offset & (size-1)) && offset >= (1<<8)) {
2629     add(tmp, base, offset & ((1<<12)-1));
2630     base = tmp;
2631     offset &= -1<<12;
2632   }
2633 
2634   if (offset >= (1<<12) * size) {
2635     add(tmp, base, offset & (((1<<12)-1)<<12));
2636     base = tmp;
2637     offset &= ~(((1<<12)-1)<<12);
2638   }
2639 
2640   return Address(base, offset);
2641 }
2642 
2643 // Checks whether offset is aligned.
2644 // Returns true if it is, else false.
2645 bool MacroAssembler::merge_alignment_check(Register base,
2646                                            size_t size,
2647                                            long cur_offset,
2648                                            long prev_offset) const {
2649   if (AvoidUnalignedAccesses) {
2650     if (base == sp) {
2651       // Checks whether low offset if aligned to pair of registers.
2652       long pair_mask = size * 2 - 1;
2653       long offset = prev_offset > cur_offset ? cur_offset : prev_offset;
2654       return (offset & pair_mask) == 0;
2655     } else { // If base is not sp, we can't guarantee the access is aligned.
2656       return false;
2657     }
2658   } else {
2659     long mask = size - 1;
2660     // Load/store pair instruction only supports element size aligned offset.
2661     return (cur_offset & mask) == 0 && (prev_offset & mask) == 0;
2662   }
2663 }
2664 
2665 // Checks whether current and previous loads/stores can be merged.
2666 // Returns true if it can be merged, else false.
2667 bool MacroAssembler::ldst_can_merge(Register rt,
2668                                     const Address &adr,
2669                                     size_t cur_size_in_bytes,
2670                                     bool is_store) const {
2671   address prev = pc() - NativeInstruction::instruction_size;
2672   address last = code()->last_insn();
2673 
2674   if (last == NULL || !nativeInstruction_at(last)->is_Imm_LdSt()) {
2675     return false;
2676   }
2677 
2678   if (adr.getMode() != Address::base_plus_offset || prev != last) {
2679     return false;
2680   }
2681 
2682   NativeLdSt* prev_ldst = NativeLdSt_at(prev);
2683   size_t prev_size_in_bytes = prev_ldst->size_in_bytes();
2684 
2685   assert(prev_size_in_bytes == 4 || prev_size_in_bytes == 8, "only supports 64/32bit merging.");
2686   assert(cur_size_in_bytes == 4 || cur_size_in_bytes == 8, "only supports 64/32bit merging.");
2687 
2688   if (cur_size_in_bytes != prev_size_in_bytes || is_store != prev_ldst->is_store()) {
2689     return false;
2690   }
2691 
2692   long max_offset = 63 * prev_size_in_bytes;
2693   long min_offset = -64 * prev_size_in_bytes;
2694 
2695   assert(prev_ldst->is_not_pre_post_index(), "pre-index or post-index is not supported to be merged.");
2696 
2697   // Only same base can be merged.
2698   if (adr.base() != prev_ldst->base()) {
2699     return false;
2700   }
2701 
2702   long cur_offset = adr.offset();
2703   long prev_offset = prev_ldst->offset();
2704   size_t diff = abs(cur_offset - prev_offset);
2705   if (diff != prev_size_in_bytes) {
2706     return false;
2707   }
2708 
2709   // Following cases can not be merged:
2710   // ldr x2, [x2, #8]
2711   // ldr x3, [x2, #16]
2712   // or:
2713   // ldr x2, [x3, #8]
2714   // ldr x2, [x3, #16]
2715   // If t1 and t2 is the same in "ldp t1, t2, [xn, #imm]", we'll get SIGILL.
2716   if (!is_store && (adr.base() == prev_ldst->target() || rt == prev_ldst->target())) {
2717     return false;
2718   }
2719 
2720   long low_offset = prev_offset > cur_offset ? cur_offset : prev_offset;
2721   // Offset range must be in ldp/stp instruction's range.
2722   if (low_offset > max_offset || low_offset < min_offset) {
2723     return false;
2724   }
2725 
2726   if (merge_alignment_check(adr.base(), prev_size_in_bytes, cur_offset, prev_offset)) {
2727     return true;
2728   }
2729 
2730   return false;
2731 }
2732 
2733 // Merge current load/store with previous load/store into ldp/stp.
2734 void MacroAssembler::merge_ldst(Register rt,
2735                                 const Address &adr,
2736                                 size_t cur_size_in_bytes,
2737                                 bool is_store) {
2738 
2739   assert(ldst_can_merge(rt, adr, cur_size_in_bytes, is_store) == true, "cur and prev must be able to be merged.");
2740 
2741   Register rt_low, rt_high;
2742   address prev = pc() - NativeInstruction::instruction_size;
2743   NativeLdSt* prev_ldst = NativeLdSt_at(prev);
2744 
2745   long offset;
2746 
2747   if (adr.offset() < prev_ldst->offset()) {
2748     offset = adr.offset();
2749     rt_low = rt;
2750     rt_high = prev_ldst->target();
2751   } else {
2752     offset = prev_ldst->offset();
2753     rt_low = prev_ldst->target();
2754     rt_high = rt;
2755   }
2756 
2757   Address adr_p = Address(prev_ldst->base(), offset);
2758   // Overwrite previous generated binary.
2759   code_section()->set_end(prev);
2760 
2761   const int sz = prev_ldst->size_in_bytes();
2762   assert(sz == 8 || sz == 4, "only supports 64/32bit merging.");
2763   if (!is_store) {
2764     BLOCK_COMMENT("merged ldr pair");
2765     if (sz == 8) {
2766       ldp(rt_low, rt_high, adr_p);
2767     } else {
2768       ldpw(rt_low, rt_high, adr_p);
2769     }
2770   } else {
2771     BLOCK_COMMENT("merged str pair");
2772     if (sz == 8) {
2773       stp(rt_low, rt_high, adr_p);
2774     } else {
2775       stpw(rt_low, rt_high, adr_p);
2776     }
2777   }
2778 }
2779 
2780 /**
2781  * Multiply 64 bit by 64 bit first loop.
2782  */
2783 void MacroAssembler::multiply_64_x_64_loop(Register x, Register xstart, Register x_xstart,
2784                                            Register y, Register y_idx, Register z,
2785                                            Register carry, Register product,
2786                                            Register idx, Register kdx) {
2787   //
2788   //  jlong carry, x[], y[], z[];
2789   //  for (int idx=ystart, kdx=ystart+1+xstart; idx >= 0; idx-, kdx--) {
2790   //    huge_128 product = y[idx] * x[xstart] + carry;
2791   //    z[kdx] = (jlong)product;
2792   //    carry  = (jlong)(product >>> 64);
2793   //  }
2794   //  z[xstart] = carry;
2795   //
2796 
2797   Label L_first_loop, L_first_loop_exit;
2798   Label L_one_x, L_one_y, L_multiply;
2799 
2800   subsw(xstart, xstart, 1);
2801   br(Assembler::MI, L_one_x);
2802 
2803   lea(rscratch1, Address(x, xstart, Address::lsl(LogBytesPerInt)));
2804   ldr(x_xstart, Address(rscratch1));
2805   ror(x_xstart, x_xstart, 32); // convert big-endian to little-endian
2806 
2807   bind(L_first_loop);
2808   subsw(idx, idx, 1);
2809   br(Assembler::MI, L_first_loop_exit);
2810   subsw(idx, idx, 1);
2811   br(Assembler::MI, L_one_y);
2812   lea(rscratch1, Address(y, idx, Address::uxtw(LogBytesPerInt)));
2813   ldr(y_idx, Address(rscratch1));
2814   ror(y_idx, y_idx, 32); // convert big-endian to little-endian
2815   bind(L_multiply);
2816 
2817   // AArch64 has a multiply-accumulate instruction that we can't use
2818   // here because it has no way to process carries, so we have to use
2819   // separate add and adc instructions.  Bah.
2820   umulh(rscratch1, x_xstart, y_idx); // x_xstart * y_idx -> rscratch1:product
2821   mul(product, x_xstart, y_idx);
2822   adds(product, product, carry);
2823   adc(carry, rscratch1, zr);   // x_xstart * y_idx + carry -> carry:product
2824 
2825   subw(kdx, kdx, 2);
2826   ror(product, product, 32); // back to big-endian
2827   str(product, offsetted_address(z, kdx, Address::uxtw(LogBytesPerInt), 0, BytesPerLong));
2828 
2829   b(L_first_loop);
2830 
2831   bind(L_one_y);
2832   ldrw(y_idx, Address(y,  0));
2833   b(L_multiply);
2834 
2835   bind(L_one_x);
2836   ldrw(x_xstart, Address(x,  0));
2837   b(L_first_loop);
2838 
2839   bind(L_first_loop_exit);
2840 }
2841 
2842 /**
2843  * Multiply 128 bit by 128. Unrolled inner loop.
2844  *
2845  */
2846 void MacroAssembler::multiply_128_x_128_loop(Register y, Register z,
2847                                              Register carry, Register carry2,
2848                                              Register idx, Register jdx,
2849                                              Register yz_idx1, Register yz_idx2,
2850                                              Register tmp, Register tmp3, Register tmp4,
2851                                              Register tmp6, Register product_hi) {
2852 
2853   //   jlong carry, x[], y[], z[];
2854   //   int kdx = ystart+1;
2855   //   for (int idx=ystart-2; idx >= 0; idx -= 2) { // Third loop
2856   //     huge_128 tmp3 = (y[idx+1] * product_hi) + z[kdx+idx+1] + carry;
2857   //     jlong carry2  = (jlong)(tmp3 >>> 64);
2858   //     huge_128 tmp4 = (y[idx]   * product_hi) + z[kdx+idx] + carry2;
2859   //     carry  = (jlong)(tmp4 >>> 64);
2860   //     z[kdx+idx+1] = (jlong)tmp3;
2861   //     z[kdx+idx] = (jlong)tmp4;
2862   //   }
2863   //   idx += 2;
2864   //   if (idx > 0) {
2865   //     yz_idx1 = (y[idx] * product_hi) + z[kdx+idx] + carry;
2866   //     z[kdx+idx] = (jlong)yz_idx1;
2867   //     carry  = (jlong)(yz_idx1 >>> 64);
2868   //   }
2869   //
2870 
2871   Label L_third_loop, L_third_loop_exit, L_post_third_loop_done;
2872 
2873   lsrw(jdx, idx, 2);
2874 
2875   bind(L_third_loop);
2876 
2877   subsw(jdx, jdx, 1);
2878   br(Assembler::MI, L_third_loop_exit);
2879   subw(idx, idx, 4);
2880 
2881   lea(rscratch1, Address(y, idx, Address::uxtw(LogBytesPerInt)));
2882 
2883   ldp(yz_idx2, yz_idx1, Address(rscratch1, 0));
2884 
2885   lea(tmp6, Address(z, idx, Address::uxtw(LogBytesPerInt)));
2886 
2887   ror(yz_idx1, yz_idx1, 32); // convert big-endian to little-endian
2888   ror(yz_idx2, yz_idx2, 32);
2889 
2890   ldp(rscratch2, rscratch1, Address(tmp6, 0));
2891 
2892   mul(tmp3, product_hi, yz_idx1);  //  yz_idx1 * product_hi -> tmp4:tmp3
2893   umulh(tmp4, product_hi, yz_idx1);
2894 
2895   ror(rscratch1, rscratch1, 32); // convert big-endian to little-endian
2896   ror(rscratch2, rscratch2, 32);
2897 
2898   mul(tmp, product_hi, yz_idx2);   //  yz_idx2 * product_hi -> carry2:tmp
2899   umulh(carry2, product_hi, yz_idx2);
2900 
2901   // propagate sum of both multiplications into carry:tmp4:tmp3
2902   adds(tmp3, tmp3, carry);
2903   adc(tmp4, tmp4, zr);
2904   adds(tmp3, tmp3, rscratch1);
2905   adcs(tmp4, tmp4, tmp);
2906   adc(carry, carry2, zr);
2907   adds(tmp4, tmp4, rscratch2);
2908   adc(carry, carry, zr);
2909 
2910   ror(tmp3, tmp3, 32); // convert little-endian to big-endian
2911   ror(tmp4, tmp4, 32);
2912   stp(tmp4, tmp3, Address(tmp6, 0));
2913 
2914   b(L_third_loop);
2915   bind (L_third_loop_exit);
2916 
2917   andw (idx, idx, 0x3);
2918   cbz(idx, L_post_third_loop_done);
2919 
2920   Label L_check_1;
2921   subsw(idx, idx, 2);
2922   br(Assembler::MI, L_check_1);
2923 
2924   lea(rscratch1, Address(y, idx, Address::uxtw(LogBytesPerInt)));
2925   ldr(yz_idx1, Address(rscratch1, 0));
2926   ror(yz_idx1, yz_idx1, 32);
2927   mul(tmp3, product_hi, yz_idx1);  //  yz_idx1 * product_hi -> tmp4:tmp3
2928   umulh(tmp4, product_hi, yz_idx1);
2929   lea(rscratch1, Address(z, idx, Address::uxtw(LogBytesPerInt)));
2930   ldr(yz_idx2, Address(rscratch1, 0));
2931   ror(yz_idx2, yz_idx2, 32);
2932 
2933   add2_with_carry(carry, tmp4, tmp3, carry, yz_idx2);
2934 
2935   ror(tmp3, tmp3, 32);
2936   str(tmp3, Address(rscratch1, 0));
2937 
2938   bind (L_check_1);
2939 
2940   andw (idx, idx, 0x1);
2941   subsw(idx, idx, 1);
2942   br(Assembler::MI, L_post_third_loop_done);
2943   ldrw(tmp4, Address(y, idx, Address::uxtw(LogBytesPerInt)));
2944   mul(tmp3, tmp4, product_hi);  //  tmp4 * product_hi -> carry2:tmp3
2945   umulh(carry2, tmp4, product_hi);
2946   ldrw(tmp4, Address(z, idx, Address::uxtw(LogBytesPerInt)));
2947 
2948   add2_with_carry(carry2, tmp3, tmp4, carry);
2949 
2950   strw(tmp3, Address(z, idx, Address::uxtw(LogBytesPerInt)));
2951   extr(carry, carry2, tmp3, 32);
2952 
2953   bind(L_post_third_loop_done);
2954 }
2955 
2956 /**
2957  * Code for BigInteger::multiplyToLen() instrinsic.
2958  *
2959  * r0: x
2960  * r1: xlen
2961  * r2: y
2962  * r3: ylen
2963  * r4:  z
2964  * r5: zlen
2965  * r10: tmp1
2966  * r11: tmp2
2967  * r12: tmp3
2968  * r13: tmp4
2969  * r14: tmp5
2970  * r15: tmp6
2971  * r16: tmp7
2972  *
2973  */
2974 void MacroAssembler::multiply_to_len(Register x, Register xlen, Register y, Register ylen,
2975                                      Register z, Register zlen,
2976                                      Register tmp1, Register tmp2, Register tmp3, Register tmp4,
2977                                      Register tmp5, Register tmp6, Register product_hi) {
2978 
2979   assert_different_registers(x, xlen, y, ylen, z, zlen, tmp1, tmp2, tmp3, tmp4, tmp5, tmp6);
2980 
2981   const Register idx = tmp1;
2982   const Register kdx = tmp2;
2983   const Register xstart = tmp3;
2984 
2985   const Register y_idx = tmp4;
2986   const Register carry = tmp5;
2987   const Register product  = xlen;
2988   const Register x_xstart = zlen;  // reuse register
2989 
2990   // First Loop.
2991   //
2992   //  final static long LONG_MASK = 0xffffffffL;
2993   //  int xstart = xlen - 1;
2994   //  int ystart = ylen - 1;
2995   //  long carry = 0;
2996   //  for (int idx=ystart, kdx=ystart+1+xstart; idx >= 0; idx-, kdx--) {
2997   //    long product = (y[idx] & LONG_MASK) * (x[xstart] & LONG_MASK) + carry;
2998   //    z[kdx] = (int)product;
2999   //    carry = product >>> 32;
3000   //  }
3001   //  z[xstart] = (int)carry;
3002   //
3003 
3004   movw(idx, ylen);      // idx = ylen;
3005   movw(kdx, zlen);      // kdx = xlen+ylen;
3006   mov(carry, zr);       // carry = 0;
3007 
3008   Label L_done;
3009 
3010   movw(xstart, xlen);
3011   subsw(xstart, xstart, 1);
3012   br(Assembler::MI, L_done);
3013 
3014   multiply_64_x_64_loop(x, xstart, x_xstart, y, y_idx, z, carry, product, idx, kdx);
3015 
3016   Label L_second_loop;
3017   cbzw(kdx, L_second_loop);
3018 
3019   Label L_carry;
3020   subw(kdx, kdx, 1);
3021   cbzw(kdx, L_carry);
3022 
3023   strw(carry, Address(z, kdx, Address::uxtw(LogBytesPerInt)));
3024   lsr(carry, carry, 32);
3025   subw(kdx, kdx, 1);
3026 
3027   bind(L_carry);
3028   strw(carry, Address(z, kdx, Address::uxtw(LogBytesPerInt)));
3029 
3030   // Second and third (nested) loops.
3031   //
3032   // for (int i = xstart-1; i >= 0; i--) { // Second loop
3033   //   carry = 0;
3034   //   for (int jdx=ystart, k=ystart+1+i; jdx >= 0; jdx--, k--) { // Third loop
3035   //     long product = (y[jdx] & LONG_MASK) * (x[i] & LONG_MASK) +
3036   //                    (z[k] & LONG_MASK) + carry;
3037   //     z[k] = (int)product;
3038   //     carry = product >>> 32;
3039   //   }
3040   //   z[i] = (int)carry;
3041   // }
3042   //
3043   // i = xlen, j = tmp1, k = tmp2, carry = tmp5, x[i] = product_hi
3044 
3045   const Register jdx = tmp1;
3046 
3047   bind(L_second_loop);
3048   mov(carry, zr);                // carry = 0;
3049   movw(jdx, ylen);               // j = ystart+1
3050 
3051   subsw(xstart, xstart, 1);      // i = xstart-1;
3052   br(Assembler::MI, L_done);
3053 
3054   str(z, Address(pre(sp, -4 * wordSize)));
3055 
3056   Label L_last_x;
3057   lea(z, offsetted_address(z, xstart, Address::uxtw(LogBytesPerInt), 4, BytesPerInt)); // z = z + k - j
3058   subsw(xstart, xstart, 1);       // i = xstart-1;
3059   br(Assembler::MI, L_last_x);
3060 
3061   lea(rscratch1, Address(x, xstart, Address::uxtw(LogBytesPerInt)));
3062   ldr(product_hi, Address(rscratch1));
3063   ror(product_hi, product_hi, 32);  // convert big-endian to little-endian
3064 
3065   Label L_third_loop_prologue;
3066   bind(L_third_loop_prologue);
3067 
3068   str(ylen, Address(sp, wordSize));
3069   stp(x, xstart, Address(sp, 2 * wordSize));
3070   multiply_128_x_128_loop(y, z, carry, x, jdx, ylen, product,
3071                           tmp2, x_xstart, tmp3, tmp4, tmp6, product_hi);
3072   ldp(z, ylen, Address(post(sp, 2 * wordSize)));
3073   ldp(x, xlen, Address(post(sp, 2 * wordSize)));   // copy old xstart -> xlen
3074 
3075   addw(tmp3, xlen, 1);
3076   strw(carry, Address(z, tmp3, Address::uxtw(LogBytesPerInt)));
3077   subsw(tmp3, tmp3, 1);
3078   br(Assembler::MI, L_done);
3079 
3080   lsr(carry, carry, 32);
3081   strw(carry, Address(z, tmp3, Address::uxtw(LogBytesPerInt)));
3082   b(L_second_loop);
3083 
3084   // Next infrequent code is moved outside loops.
3085   bind(L_last_x);
3086   ldrw(product_hi, Address(x,  0));
3087   b(L_third_loop_prologue);
3088 
3089   bind(L_done);
3090 }
3091 
3092 // Code for BigInteger::mulAdd instrinsic
3093 // out     = r0
3094 // in      = r1
3095 // offset  = r2  (already out.length-offset)
3096 // len     = r3
3097 // k       = r4
3098 //
3099 // pseudo code from java implementation:
3100 // carry = 0;
3101 // offset = out.length-offset - 1;
3102 // for (int j=len-1; j >= 0; j--) {
3103 //     product = (in[j] & LONG_MASK) * kLong + (out[offset] & LONG_MASK) + carry;
3104 //     out[offset--] = (int)product;
3105 //     carry = product >>> 32;
3106 // }
3107 // return (int)carry;
3108 void MacroAssembler::mul_add(Register out, Register in, Register offset,
3109       Register len, Register k) {
3110     Label LOOP, END;
3111     // pre-loop
3112     cmp(len, zr); // cmp, not cbz/cbnz: to use condition twice => less branches
3113     csel(out, zr, out, Assembler::EQ);
3114     br(Assembler::EQ, END);
3115     add(in, in, len, LSL, 2); // in[j+1] address
3116     add(offset, out, offset, LSL, 2); // out[offset + 1] address
3117     mov(out, zr); // used to keep carry now
3118     BIND(LOOP);
3119     ldrw(rscratch1, Address(pre(in, -4)));
3120     madd(rscratch1, rscratch1, k, out);
3121     ldrw(rscratch2, Address(pre(offset, -4)));
3122     add(rscratch1, rscratch1, rscratch2);
3123     strw(rscratch1, Address(offset));
3124     lsr(out, rscratch1, 32);
3125     subs(len, len, 1);
3126     br(Assembler::NE, LOOP);
3127     BIND(END);
3128 }
3129 
3130 /**
3131  * Emits code to update CRC-32 with a byte value according to constants in table
3132  *
3133  * @param [in,out]crc   Register containing the crc.
3134  * @param [in]val       Register containing the byte to fold into the CRC.
3135  * @param [in]table     Register containing the table of crc constants.
3136  *
3137  * uint32_t crc;
3138  * val = crc_table[(val ^ crc) & 0xFF];
3139  * crc = val ^ (crc >> 8);
3140  *
3141  */
3142 void MacroAssembler::update_byte_crc32(Register crc, Register val, Register table) {
3143   eor(val, val, crc);
3144   andr(val, val, 0xff);
3145   ldrw(val, Address(table, val, Address::lsl(2)));
3146   eor(crc, val, crc, Assembler::LSR, 8);
3147 }
3148 
3149 /**
3150  * Emits code to update CRC-32 with a 32-bit value according to tables 0 to 3
3151  *
3152  * @param [in,out]crc   Register containing the crc.
3153  * @param [in]v         Register containing the 32-bit to fold into the CRC.
3154  * @param [in]table0    Register containing table 0 of crc constants.
3155  * @param [in]table1    Register containing table 1 of crc constants.
3156  * @param [in]table2    Register containing table 2 of crc constants.
3157  * @param [in]table3    Register containing table 3 of crc constants.
3158  *
3159  * uint32_t crc;
3160  *   v = crc ^ v
3161  *   crc = table3[v&0xff]^table2[(v>>8)&0xff]^table1[(v>>16)&0xff]^table0[v>>24]
3162  *
3163  */
3164 void MacroAssembler::update_word_crc32(Register crc, Register v, Register tmp,
3165         Register table0, Register table1, Register table2, Register table3,
3166         bool upper) {
3167   eor(v, crc, v, upper ? LSR:LSL, upper ? 32:0);
3168   uxtb(tmp, v);
3169   ldrw(crc, Address(table3, tmp, Address::lsl(2)));
3170   ubfx(tmp, v, 8, 8);
3171   ldrw(tmp, Address(table2, tmp, Address::lsl(2)));
3172   eor(crc, crc, tmp);
3173   ubfx(tmp, v, 16, 8);
3174   ldrw(tmp, Address(table1, tmp, Address::lsl(2)));
3175   eor(crc, crc, tmp);
3176   ubfx(tmp, v, 24, 8);
3177   ldrw(tmp, Address(table0, tmp, Address::lsl(2)));
3178   eor(crc, crc, tmp);
3179 }
3180 
3181 void MacroAssembler::kernel_crc32_using_crc32(Register crc, Register buf,
3182         Register len, Register tmp0, Register tmp1, Register tmp2,
3183         Register tmp3) {
3184     Label CRC_by64_loop, CRC_by4_loop, CRC_by1_loop, CRC_less64, CRC_by64_pre, CRC_by32_loop, CRC_less32, L_exit;
3185     assert_different_registers(crc, buf, len, tmp0, tmp1, tmp2, tmp3);
3186 
3187     mvnw(crc, crc);
3188 
3189     subs(len, len, 128);
3190     br(Assembler::GE, CRC_by64_pre);
3191   BIND(CRC_less64);
3192     adds(len, len, 128-32);
3193     br(Assembler::GE, CRC_by32_loop);
3194   BIND(CRC_less32);
3195     adds(len, len, 32-4);
3196     br(Assembler::GE, CRC_by4_loop);
3197     adds(len, len, 4);
3198     br(Assembler::GT, CRC_by1_loop);
3199     b(L_exit);
3200 
3201   BIND(CRC_by32_loop);
3202     ldp(tmp0, tmp1, Address(post(buf, 16)));
3203     subs(len, len, 32);
3204     crc32x(crc, crc, tmp0);
3205     ldr(tmp2, Address(post(buf, 8)));
3206     crc32x(crc, crc, tmp1);
3207     ldr(tmp3, Address(post(buf, 8)));
3208     crc32x(crc, crc, tmp2);
3209     crc32x(crc, crc, tmp3);
3210     br(Assembler::GE, CRC_by32_loop);
3211     cmn(len, 32);
3212     br(Assembler::NE, CRC_less32);
3213     b(L_exit);
3214 
3215   BIND(CRC_by4_loop);
3216     ldrw(tmp0, Address(post(buf, 4)));
3217     subs(len, len, 4);
3218     crc32w(crc, crc, tmp0);
3219     br(Assembler::GE, CRC_by4_loop);
3220     adds(len, len, 4);
3221     br(Assembler::LE, L_exit);
3222   BIND(CRC_by1_loop);
3223     ldrb(tmp0, Address(post(buf, 1)));
3224     subs(len, len, 1);
3225     crc32b(crc, crc, tmp0);
3226     br(Assembler::GT, CRC_by1_loop);
3227     b(L_exit);
3228 
3229   BIND(CRC_by64_pre);
3230     sub(buf, buf, 8);
3231     ldp(tmp0, tmp1, Address(buf, 8));
3232     crc32x(crc, crc, tmp0);
3233     ldr(tmp2, Address(buf, 24));
3234     crc32x(crc, crc, tmp1);
3235     ldr(tmp3, Address(buf, 32));
3236     crc32x(crc, crc, tmp2);
3237     ldr(tmp0, Address(buf, 40));
3238     crc32x(crc, crc, tmp3);
3239     ldr(tmp1, Address(buf, 48));
3240     crc32x(crc, crc, tmp0);
3241     ldr(tmp2, Address(buf, 56));
3242     crc32x(crc, crc, tmp1);
3243     ldr(tmp3, Address(pre(buf, 64)));
3244 
3245     b(CRC_by64_loop);
3246 
3247     align(CodeEntryAlignment);
3248   BIND(CRC_by64_loop);
3249     subs(len, len, 64);
3250     crc32x(crc, crc, tmp2);
3251     ldr(tmp0, Address(buf, 8));
3252     crc32x(crc, crc, tmp3);
3253     ldr(tmp1, Address(buf, 16));
3254     crc32x(crc, crc, tmp0);
3255     ldr(tmp2, Address(buf, 24));
3256     crc32x(crc, crc, tmp1);
3257     ldr(tmp3, Address(buf, 32));
3258     crc32x(crc, crc, tmp2);
3259     ldr(tmp0, Address(buf, 40));
3260     crc32x(crc, crc, tmp3);
3261     ldr(tmp1, Address(buf, 48));
3262     crc32x(crc, crc, tmp0);
3263     ldr(tmp2, Address(buf, 56));
3264     crc32x(crc, crc, tmp1);
3265     ldr(tmp3, Address(pre(buf, 64)));
3266     br(Assembler::GE, CRC_by64_loop);
3267 
3268     // post-loop
3269     crc32x(crc, crc, tmp2);
3270     crc32x(crc, crc, tmp3);
3271 
3272     sub(len, len, 64);
3273     add(buf, buf, 8);
3274     cmn(len, 128);
3275     br(Assembler::NE, CRC_less64);
3276   BIND(L_exit);
3277     mvnw(crc, crc);
3278 }
3279 
3280 /**
3281  * @param crc   register containing existing CRC (32-bit)
3282  * @param buf   register pointing to input byte buffer (byte*)
3283  * @param len   register containing number of bytes
3284  * @param table register that will contain address of CRC table
3285  * @param tmp   scratch register
3286  */
3287 void MacroAssembler::kernel_crc32(Register crc, Register buf, Register len,
3288         Register table0, Register table1, Register table2, Register table3,
3289         Register tmp, Register tmp2, Register tmp3) {
3290   Label L_by16, L_by16_loop, L_by4, L_by4_loop, L_by1, L_by1_loop, L_exit;
3291   unsigned long offset;
3292 
3293   if (UseCRC32) {
3294       kernel_crc32_using_crc32(crc, buf, len, table0, table1, table2, table3);
3295       return;
3296   }
3297 
3298     mvnw(crc, crc);
3299 
3300     adrp(table0, ExternalAddress(StubRoutines::crc_table_addr()), offset);
3301     if (offset) add(table0, table0, offset);
3302     add(table1, table0, 1*256*sizeof(juint));
3303     add(table2, table0, 2*256*sizeof(juint));
3304     add(table3, table0, 3*256*sizeof(juint));
3305 
3306   if (UseNeon) {
3307       cmp(len, 64);
3308       br(Assembler::LT, L_by16);
3309       eor(v16, T16B, v16, v16);
3310 
3311     Label L_fold;
3312 
3313       add(tmp, table0, 4*256*sizeof(juint)); // Point at the Neon constants
3314 
3315       ld1(v0, v1, T2D, post(buf, 32));
3316       ld1r(v4, T2D, post(tmp, 8));
3317       ld1r(v5, T2D, post(tmp, 8));
3318       ld1r(v6, T2D, post(tmp, 8));
3319       ld1r(v7, T2D, post(tmp, 8));
3320       mov(v16, T4S, 0, crc);
3321 
3322       eor(v0, T16B, v0, v16);
3323       sub(len, len, 64);
3324 
3325     BIND(L_fold);
3326       pmull(v22, T8H, v0, v5, T8B);
3327       pmull(v20, T8H, v0, v7, T8B);
3328       pmull(v23, T8H, v0, v4, T8B);
3329       pmull(v21, T8H, v0, v6, T8B);
3330 
3331       pmull2(v18, T8H, v0, v5, T16B);
3332       pmull2(v16, T8H, v0, v7, T16B);
3333       pmull2(v19, T8H, v0, v4, T16B);
3334       pmull2(v17, T8H, v0, v6, T16B);
3335 
3336       uzp1(v24, T8H, v20, v22);
3337       uzp2(v25, T8H, v20, v22);
3338       eor(v20, T16B, v24, v25);
3339 
3340       uzp1(v26, T8H, v16, v18);
3341       uzp2(v27, T8H, v16, v18);
3342       eor(v16, T16B, v26, v27);
3343 
3344       ushll2(v22, T4S, v20, T8H, 8);
3345       ushll(v20, T4S, v20, T4H, 8);
3346 
3347       ushll2(v18, T4S, v16, T8H, 8);
3348       ushll(v16, T4S, v16, T4H, 8);
3349 
3350       eor(v22, T16B, v23, v22);
3351       eor(v18, T16B, v19, v18);
3352       eor(v20, T16B, v21, v20);
3353       eor(v16, T16B, v17, v16);
3354 
3355       uzp1(v17, T2D, v16, v20);
3356       uzp2(v21, T2D, v16, v20);
3357       eor(v17, T16B, v17, v21);
3358 
3359       ushll2(v20, T2D, v17, T4S, 16);
3360       ushll(v16, T2D, v17, T2S, 16);
3361 
3362       eor(v20, T16B, v20, v22);
3363       eor(v16, T16B, v16, v18);
3364 
3365       uzp1(v17, T2D, v20, v16);
3366       uzp2(v21, T2D, v20, v16);
3367       eor(v28, T16B, v17, v21);
3368 
3369       pmull(v22, T8H, v1, v5, T8B);
3370       pmull(v20, T8H, v1, v7, T8B);
3371       pmull(v23, T8H, v1, v4, T8B);
3372       pmull(v21, T8H, v1, v6, T8B);
3373 
3374       pmull2(v18, T8H, v1, v5, T16B);
3375       pmull2(v16, T8H, v1, v7, T16B);
3376       pmull2(v19, T8H, v1, v4, T16B);
3377       pmull2(v17, T8H, v1, v6, T16B);
3378 
3379       ld1(v0, v1, T2D, post(buf, 32));
3380 
3381       uzp1(v24, T8H, v20, v22);
3382       uzp2(v25, T8H, v20, v22);
3383       eor(v20, T16B, v24, v25);
3384 
3385       uzp1(v26, T8H, v16, v18);
3386       uzp2(v27, T8H, v16, v18);
3387       eor(v16, T16B, v26, v27);
3388 
3389       ushll2(v22, T4S, v20, T8H, 8);
3390       ushll(v20, T4S, v20, T4H, 8);
3391 
3392       ushll2(v18, T4S, v16, T8H, 8);
3393       ushll(v16, T4S, v16, T4H, 8);
3394 
3395       eor(v22, T16B, v23, v22);
3396       eor(v18, T16B, v19, v18);
3397       eor(v20, T16B, v21, v20);
3398       eor(v16, T16B, v17, v16);
3399 
3400       uzp1(v17, T2D, v16, v20);
3401       uzp2(v21, T2D, v16, v20);
3402       eor(v16, T16B, v17, v21);
3403 
3404       ushll2(v20, T2D, v16, T4S, 16);
3405       ushll(v16, T2D, v16, T2S, 16);
3406 
3407       eor(v20, T16B, v22, v20);
3408       eor(v16, T16B, v16, v18);
3409 
3410       uzp1(v17, T2D, v20, v16);
3411       uzp2(v21, T2D, v20, v16);
3412       eor(v20, T16B, v17, v21);
3413 
3414       shl(v16, T2D, v28, 1);
3415       shl(v17, T2D, v20, 1);
3416 
3417       eor(v0, T16B, v0, v16);
3418       eor(v1, T16B, v1, v17);
3419 
3420       subs(len, len, 32);
3421       br(Assembler::GE, L_fold);
3422 
3423       mov(crc, 0);
3424       mov(tmp, v0, T1D, 0);
3425       update_word_crc32(crc, tmp, tmp2, table0, table1, table2, table3, false);
3426       update_word_crc32(crc, tmp, tmp2, table0, table1, table2, table3, true);
3427       mov(tmp, v0, T1D, 1);
3428       update_word_crc32(crc, tmp, tmp2, table0, table1, table2, table3, false);
3429       update_word_crc32(crc, tmp, tmp2, table0, table1, table2, table3, true);
3430       mov(tmp, v1, T1D, 0);
3431       update_word_crc32(crc, tmp, tmp2, table0, table1, table2, table3, false);
3432       update_word_crc32(crc, tmp, tmp2, table0, table1, table2, table3, true);
3433       mov(tmp, v1, T1D, 1);
3434       update_word_crc32(crc, tmp, tmp2, table0, table1, table2, table3, false);
3435       update_word_crc32(crc, tmp, tmp2, table0, table1, table2, table3, true);
3436 
3437       add(len, len, 32);
3438   }
3439 
3440   BIND(L_by16);
3441     subs(len, len, 16);
3442     br(Assembler::GE, L_by16_loop);
3443     adds(len, len, 16-4);
3444     br(Assembler::GE, L_by4_loop);
3445     adds(len, len, 4);
3446     br(Assembler::GT, L_by1_loop);
3447     b(L_exit);
3448 
3449   BIND(L_by4_loop);
3450     ldrw(tmp, Address(post(buf, 4)));
3451     update_word_crc32(crc, tmp, tmp2, table0, table1, table2, table3);
3452     subs(len, len, 4);
3453     br(Assembler::GE, L_by4_loop);
3454     adds(len, len, 4);
3455     br(Assembler::LE, L_exit);
3456   BIND(L_by1_loop);
3457     subs(len, len, 1);
3458     ldrb(tmp, Address(post(buf, 1)));
3459     update_byte_crc32(crc, tmp, table0);
3460     br(Assembler::GT, L_by1_loop);
3461     b(L_exit);
3462 
3463     align(CodeEntryAlignment);
3464   BIND(L_by16_loop);
3465     subs(len, len, 16);
3466     ldp(tmp, tmp3, Address(post(buf, 16)));
3467     update_word_crc32(crc, tmp, tmp2, table0, table1, table2, table3, false);
3468     update_word_crc32(crc, tmp, tmp2, table0, table1, table2, table3, true);
3469     update_word_crc32(crc, tmp3, tmp2, table0, table1, table2, table3, false);
3470     update_word_crc32(crc, tmp3, tmp2, table0, table1, table2, table3, true);
3471     br(Assembler::GE, L_by16_loop);
3472     adds(len, len, 16-4);
3473     br(Assembler::GE, L_by4_loop);
3474     adds(len, len, 4);
3475     br(Assembler::GT, L_by1_loop);
3476   BIND(L_exit);
3477     mvnw(crc, crc);
3478 }
3479 
3480 void MacroAssembler::kernel_crc32c_using_crc32c(Register crc, Register buf,
3481         Register len, Register tmp0, Register tmp1, Register tmp2,
3482         Register tmp3) {
3483     Label CRC_by64_loop, CRC_by4_loop, CRC_by1_loop, CRC_less64, CRC_by64_pre, CRC_by32_loop, CRC_less32, L_exit;
3484     assert_different_registers(crc, buf, len, tmp0, tmp1, tmp2, tmp3);
3485 
3486     subs(len, len, 128);
3487     br(Assembler::GE, CRC_by64_pre);
3488   BIND(CRC_less64);
3489     adds(len, len, 128-32);
3490     br(Assembler::GE, CRC_by32_loop);
3491   BIND(CRC_less32);
3492     adds(len, len, 32-4);
3493     br(Assembler::GE, CRC_by4_loop);
3494     adds(len, len, 4);
3495     br(Assembler::GT, CRC_by1_loop);
3496     b(L_exit);
3497 
3498   BIND(CRC_by32_loop);
3499     ldp(tmp0, tmp1, Address(post(buf, 16)));
3500     subs(len, len, 32);
3501     crc32cx(crc, crc, tmp0);
3502     ldr(tmp2, Address(post(buf, 8)));
3503     crc32cx(crc, crc, tmp1);
3504     ldr(tmp3, Address(post(buf, 8)));
3505     crc32cx(crc, crc, tmp2);
3506     crc32cx(crc, crc, tmp3);
3507     br(Assembler::GE, CRC_by32_loop);
3508     cmn(len, 32);
3509     br(Assembler::NE, CRC_less32);
3510     b(L_exit);
3511 
3512   BIND(CRC_by4_loop);
3513     ldrw(tmp0, Address(post(buf, 4)));
3514     subs(len, len, 4);
3515     crc32cw(crc, crc, tmp0);
3516     br(Assembler::GE, CRC_by4_loop);
3517     adds(len, len, 4);
3518     br(Assembler::LE, L_exit);
3519   BIND(CRC_by1_loop);
3520     ldrb(tmp0, Address(post(buf, 1)));
3521     subs(len, len, 1);
3522     crc32cb(crc, crc, tmp0);
3523     br(Assembler::GT, CRC_by1_loop);
3524     b(L_exit);
3525 
3526   BIND(CRC_by64_pre);
3527     sub(buf, buf, 8);
3528     ldp(tmp0, tmp1, Address(buf, 8));
3529     crc32cx(crc, crc, tmp0);
3530     ldr(tmp2, Address(buf, 24));
3531     crc32cx(crc, crc, tmp1);
3532     ldr(tmp3, Address(buf, 32));
3533     crc32cx(crc, crc, tmp2);
3534     ldr(tmp0, Address(buf, 40));
3535     crc32cx(crc, crc, tmp3);
3536     ldr(tmp1, Address(buf, 48));
3537     crc32cx(crc, crc, tmp0);
3538     ldr(tmp2, Address(buf, 56));
3539     crc32cx(crc, crc, tmp1);
3540     ldr(tmp3, Address(pre(buf, 64)));
3541 
3542     b(CRC_by64_loop);
3543 
3544     align(CodeEntryAlignment);
3545   BIND(CRC_by64_loop);
3546     subs(len, len, 64);
3547     crc32cx(crc, crc, tmp2);
3548     ldr(tmp0, Address(buf, 8));
3549     crc32cx(crc, crc, tmp3);
3550     ldr(tmp1, Address(buf, 16));
3551     crc32cx(crc, crc, tmp0);
3552     ldr(tmp2, Address(buf, 24));
3553     crc32cx(crc, crc, tmp1);
3554     ldr(tmp3, Address(buf, 32));
3555     crc32cx(crc, crc, tmp2);
3556     ldr(tmp0, Address(buf, 40));
3557     crc32cx(crc, crc, tmp3);
3558     ldr(tmp1, Address(buf, 48));
3559     crc32cx(crc, crc, tmp0);
3560     ldr(tmp2, Address(buf, 56));
3561     crc32cx(crc, crc, tmp1);
3562     ldr(tmp3, Address(pre(buf, 64)));
3563     br(Assembler::GE, CRC_by64_loop);
3564 
3565     // post-loop
3566     crc32cx(crc, crc, tmp2);
3567     crc32cx(crc, crc, tmp3);
3568 
3569     sub(len, len, 64);
3570     add(buf, buf, 8);
3571     cmn(len, 128);
3572     br(Assembler::NE, CRC_less64);
3573   BIND(L_exit);
3574 }
3575 
3576 /**
3577  * @param crc   register containing existing CRC (32-bit)
3578  * @param buf   register pointing to input byte buffer (byte*)
3579  * @param len   register containing number of bytes
3580  * @param table register that will contain address of CRC table
3581  * @param tmp   scratch register
3582  */
3583 void MacroAssembler::kernel_crc32c(Register crc, Register buf, Register len,
3584         Register table0, Register table1, Register table2, Register table3,
3585         Register tmp, Register tmp2, Register tmp3) {
3586   kernel_crc32c_using_crc32c(crc, buf, len, table0, table1, table2, table3);
3587 }
3588 
3589 
3590 SkipIfEqual::SkipIfEqual(
3591     MacroAssembler* masm, const bool* flag_addr, bool value) {
3592   _masm = masm;
3593   unsigned long offset;
3594   _masm->adrp(rscratch1, ExternalAddress((address)flag_addr), offset);
3595   _masm->ldrb(rscratch1, Address(rscratch1, offset));
3596   _masm->cbzw(rscratch1, _label);
3597 }
3598 
3599 SkipIfEqual::~SkipIfEqual() {
3600   _masm->bind(_label);
3601 }
3602 
3603 void MacroAssembler::addptr(const Address &dst, int32_t src) {
3604   Address adr;
3605   switch(dst.getMode()) {
3606   case Address::base_plus_offset:
3607     // This is the expected mode, although we allow all the other
3608     // forms below.
3609     adr = form_address(rscratch2, dst.base(), dst.offset(), LogBytesPerWord);
3610     break;
3611   default:
3612     lea(rscratch2, dst);
3613     adr = Address(rscratch2);
3614     break;
3615   }
3616   ldr(rscratch1, adr);
3617   add(rscratch1, rscratch1, src);
3618   str(rscratch1, adr);
3619 }
3620 
3621 void MacroAssembler::cmpptr(Register src1, Address src2) {
3622   unsigned long offset;
3623   adrp(rscratch1, src2, offset);
3624   ldr(rscratch1, Address(rscratch1, offset));
3625   cmp(src1, rscratch1);
3626 }
3627 
3628 void MacroAssembler::cmpoop(Register obj1, Register obj2) {
3629   BarrierSetAssembler* bs = BarrierSet::barrier_set()->barrier_set_assembler();
3630   bs->obj_equals(this, obj1, obj2);
3631 }
3632 
3633 void MacroAssembler::load_klass(Register dst, Register src) {
3634   if (UseCompressedClassPointers) {
3635     ldrw(dst, Address(src, oopDesc::klass_offset_in_bytes()));
3636     decode_klass_not_null(dst);
3637   } else {
3638     ldr(dst, Address(src, oopDesc::klass_offset_in_bytes()));
3639   }
3640 }
3641 
3642 // ((OopHandle)result).resolve();
3643 void MacroAssembler::resolve_oop_handle(Register result, Register tmp) {
3644   // OopHandle::resolve is an indirection.
3645   access_load_at(T_OBJECT, IN_NATIVE, result, Address(result, 0), tmp, noreg);
3646 }
3647 
3648 void MacroAssembler::load_mirror(Register dst, Register method, Register tmp) {
3649   const int mirror_offset = in_bytes(Klass::java_mirror_offset());
3650   ldr(dst, Address(rmethod, Method::const_offset()));
3651   ldr(dst, Address(dst, ConstMethod::constants_offset()));
3652   ldr(dst, Address(dst, ConstantPool::pool_holder_offset_in_bytes()));
3653   ldr(dst, Address(dst, mirror_offset));
3654   resolve_oop_handle(dst, tmp);
3655 }
3656 
3657 void MacroAssembler::cmp_klass(Register oop, Register trial_klass, Register tmp) {
3658   if (UseCompressedClassPointers) {
3659     ldrw(tmp, Address(oop, oopDesc::klass_offset_in_bytes()));
3660     if (Universe::narrow_klass_base() == NULL) {
3661       cmp(trial_klass, tmp, LSL, Universe::narrow_klass_shift());
3662       return;
3663     } else if (((uint64_t)Universe::narrow_klass_base() & 0xffffffff) == 0
3664                && Universe::narrow_klass_shift() == 0) {
3665       // Only the bottom 32 bits matter
3666       cmpw(trial_klass, tmp);
3667       return;
3668     }
3669     decode_klass_not_null(tmp);
3670   } else {
3671     ldr(tmp, Address(oop, oopDesc::klass_offset_in_bytes()));
3672   }
3673   cmp(trial_klass, tmp);
3674 }
3675 
3676 void MacroAssembler::load_prototype_header(Register dst, Register src) {
3677   load_klass(dst, src);
3678   ldr(dst, Address(dst, Klass::prototype_header_offset()));
3679 }
3680 
3681 void MacroAssembler::store_klass(Register dst, Register src) {
3682   // FIXME: Should this be a store release?  concurrent gcs assumes
3683   // klass length is valid if klass field is not null.
3684   if (UseCompressedClassPointers) {
3685     encode_klass_not_null(src);
3686     strw(src, Address(dst, oopDesc::klass_offset_in_bytes()));
3687   } else {
3688     str(src, Address(dst, oopDesc::klass_offset_in_bytes()));
3689   }
3690 }
3691 
3692 void MacroAssembler::store_klass_gap(Register dst, Register src) {
3693   if (UseCompressedClassPointers) {
3694     // Store to klass gap in destination
3695     strw(src, Address(dst, oopDesc::klass_gap_offset_in_bytes()));
3696   }
3697 }
3698 
3699 // Algorithm must match CompressedOops::encode.
3700 void MacroAssembler::encode_heap_oop(Register d, Register s) {
3701 #ifdef ASSERT
3702   verify_heapbase("MacroAssembler::encode_heap_oop: heap base corrupted?");
3703 #endif
3704   verify_oop(s, "broken oop in encode_heap_oop");
3705   if (Universe::narrow_oop_base() == NULL) {
3706     if (Universe::narrow_oop_shift() != 0) {
3707       assert (LogMinObjAlignmentInBytes == Universe::narrow_oop_shift(), "decode alg wrong");
3708       lsr(d, s, LogMinObjAlignmentInBytes);
3709     } else {
3710       mov(d, s);
3711     }
3712   } else {
3713     subs(d, s, rheapbase);
3714     csel(d, d, zr, Assembler::HS);
3715     lsr(d, d, LogMinObjAlignmentInBytes);
3716 
3717     /*  Old algorithm: is this any worse?
3718     Label nonnull;
3719     cbnz(r, nonnull);
3720     sub(r, r, rheapbase);
3721     bind(nonnull);
3722     lsr(r, r, LogMinObjAlignmentInBytes);
3723     */
3724   }
3725 }
3726 
3727 void MacroAssembler::encode_heap_oop_not_null(Register r) {
3728 #ifdef ASSERT
3729   verify_heapbase("MacroAssembler::encode_heap_oop_not_null: heap base corrupted?");
3730   if (CheckCompressedOops) {
3731     Label ok;
3732     cbnz(r, ok);
3733     stop("null oop passed to encode_heap_oop_not_null");
3734     bind(ok);
3735   }
3736 #endif
3737   verify_oop(r, "broken oop in encode_heap_oop_not_null");
3738   if (Universe::narrow_oop_base() != NULL) {
3739     sub(r, r, rheapbase);
3740   }
3741   if (Universe::narrow_oop_shift() != 0) {
3742     assert (LogMinObjAlignmentInBytes == Universe::narrow_oop_shift(), "decode alg wrong");
3743     lsr(r, r, LogMinObjAlignmentInBytes);
3744   }
3745 }
3746 
3747 void MacroAssembler::encode_heap_oop_not_null(Register dst, Register src) {
3748 #ifdef ASSERT
3749   verify_heapbase("MacroAssembler::encode_heap_oop_not_null2: heap base corrupted?");
3750   if (CheckCompressedOops) {
3751     Label ok;
3752     cbnz(src, ok);
3753     stop("null oop passed to encode_heap_oop_not_null2");
3754     bind(ok);
3755   }
3756 #endif
3757   verify_oop(src, "broken oop in encode_heap_oop_not_null2");
3758 
3759   Register data = src;
3760   if (Universe::narrow_oop_base() != NULL) {
3761     sub(dst, src, rheapbase);
3762     data = dst;
3763   }
3764   if (Universe::narrow_oop_shift() != 0) {
3765     assert (LogMinObjAlignmentInBytes == Universe::narrow_oop_shift(), "decode alg wrong");
3766     lsr(dst, data, LogMinObjAlignmentInBytes);
3767     data = dst;
3768   }
3769   if (data == src)
3770     mov(dst, src);
3771 }
3772 
3773 void  MacroAssembler::decode_heap_oop(Register d, Register s) {
3774 #ifdef ASSERT
3775   verify_heapbase("MacroAssembler::decode_heap_oop: heap base corrupted?");
3776 #endif
3777   if (Universe::narrow_oop_base() == NULL) {
3778     if (Universe::narrow_oop_shift() != 0 || d != s) {
3779       lsl(d, s, Universe::narrow_oop_shift());
3780     }
3781   } else {
3782     Label done;
3783     if (d != s)
3784       mov(d, s);
3785     cbz(s, done);
3786     add(d, rheapbase, s, Assembler::LSL, LogMinObjAlignmentInBytes);
3787     bind(done);
3788   }
3789   verify_oop(d, "broken oop in decode_heap_oop");
3790 }
3791 
3792 void  MacroAssembler::decode_heap_oop_not_null(Register r) {
3793   assert (UseCompressedOops, "should only be used for compressed headers");
3794   assert (Universe::heap() != NULL, "java heap should be initialized");
3795   // Cannot assert, unverified entry point counts instructions (see .ad file)
3796   // vtableStubs also counts instructions in pd_code_size_limit.
3797   // Also do not verify_oop as this is called by verify_oop.
3798   if (Universe::narrow_oop_shift() != 0) {
3799     assert(LogMinObjAlignmentInBytes == Universe::narrow_oop_shift(), "decode alg wrong");
3800     if (Universe::narrow_oop_base() != NULL) {
3801       add(r, rheapbase, r, Assembler::LSL, LogMinObjAlignmentInBytes);
3802     } else {
3803       add(r, zr, r, Assembler::LSL, LogMinObjAlignmentInBytes);
3804     }
3805   } else {
3806     assert (Universe::narrow_oop_base() == NULL, "sanity");
3807   }
3808 }
3809 
3810 void  MacroAssembler::decode_heap_oop_not_null(Register dst, Register src) {
3811   assert (UseCompressedOops, "should only be used for compressed headers");
3812   assert (Universe::heap() != NULL, "java heap should be initialized");
3813   // Cannot assert, unverified entry point counts instructions (see .ad file)
3814   // vtableStubs also counts instructions in pd_code_size_limit.
3815   // Also do not verify_oop as this is called by verify_oop.
3816   if (Universe::narrow_oop_shift() != 0) {
3817     assert(LogMinObjAlignmentInBytes == Universe::narrow_oop_shift(), "decode alg wrong");
3818     if (Universe::narrow_oop_base() != NULL) {
3819       add(dst, rheapbase, src, Assembler::LSL, LogMinObjAlignmentInBytes);
3820     } else {
3821       add(dst, zr, src, Assembler::LSL, LogMinObjAlignmentInBytes);
3822     }
3823   } else {
3824     assert (Universe::narrow_oop_base() == NULL, "sanity");
3825     if (dst != src) {
3826       mov(dst, src);
3827     }
3828   }
3829 }
3830 
3831 void MacroAssembler::encode_klass_not_null(Register dst, Register src) {
3832   if (Universe::narrow_klass_base() == NULL) {
3833     if (Universe::narrow_klass_shift() != 0) {
3834       assert (LogKlassAlignmentInBytes == Universe::narrow_klass_shift(), "decode alg wrong");
3835       lsr(dst, src, LogKlassAlignmentInBytes);
3836     } else {
3837       if (dst != src) mov(dst, src);
3838     }
3839     return;
3840   }
3841 
3842   if (use_XOR_for_compressed_class_base) {
3843     if (Universe::narrow_klass_shift() != 0) {
3844       eor(dst, src, (uint64_t)Universe::narrow_klass_base());
3845       lsr(dst, dst, LogKlassAlignmentInBytes);
3846     } else {
3847       eor(dst, src, (uint64_t)Universe::narrow_klass_base());
3848     }
3849     return;
3850   }
3851 
3852   if (((uint64_t)Universe::narrow_klass_base() & 0xffffffff) == 0
3853       && Universe::narrow_klass_shift() == 0) {
3854     movw(dst, src);
3855     return;
3856   }
3857 
3858 #ifdef ASSERT
3859   verify_heapbase("MacroAssembler::encode_klass_not_null2: heap base corrupted?");
3860 #endif
3861 
3862   Register rbase = dst;
3863   if (dst == src) rbase = rheapbase;
3864   mov(rbase, (uint64_t)Universe::narrow_klass_base());
3865   sub(dst, src, rbase);
3866   if (Universe::narrow_klass_shift() != 0) {
3867     assert (LogKlassAlignmentInBytes == Universe::narrow_klass_shift(), "decode alg wrong");
3868     lsr(dst, dst, LogKlassAlignmentInBytes);
3869   }
3870   if (dst == src) reinit_heapbase();
3871 }
3872 
3873 void MacroAssembler::encode_klass_not_null(Register r) {
3874   encode_klass_not_null(r, r);
3875 }
3876 
3877 void  MacroAssembler::decode_klass_not_null(Register dst, Register src) {
3878   Register rbase = dst;
3879   assert (UseCompressedClassPointers, "should only be used for compressed headers");
3880 
3881   if (Universe::narrow_klass_base() == NULL) {
3882     if (Universe::narrow_klass_shift() != 0) {
3883       assert(LogKlassAlignmentInBytes == Universe::narrow_klass_shift(), "decode alg wrong");
3884       lsl(dst, src, LogKlassAlignmentInBytes);
3885     } else {
3886       if (dst != src) mov(dst, src);
3887     }
3888     return;
3889   }
3890 
3891   if (use_XOR_for_compressed_class_base) {
3892     if (Universe::narrow_klass_shift() != 0) {
3893       lsl(dst, src, LogKlassAlignmentInBytes);
3894       eor(dst, dst, (uint64_t)Universe::narrow_klass_base());
3895     } else {
3896       eor(dst, src, (uint64_t)Universe::narrow_klass_base());
3897     }
3898     return;
3899   }
3900 
3901   if (((uint64_t)Universe::narrow_klass_base() & 0xffffffff) == 0
3902       && Universe::narrow_klass_shift() == 0) {
3903     if (dst != src)
3904       movw(dst, src);
3905     movk(dst, (uint64_t)Universe::narrow_klass_base() >> 32, 32);
3906     return;
3907   }
3908 
3909   // Cannot assert, unverified entry point counts instructions (see .ad file)
3910   // vtableStubs also counts instructions in pd_code_size_limit.
3911   // Also do not verify_oop as this is called by verify_oop.
3912   if (dst == src) rbase = rheapbase;
3913   mov(rbase, (uint64_t)Universe::narrow_klass_base());
3914   if (Universe::narrow_klass_shift() != 0) {
3915     assert(LogKlassAlignmentInBytes == Universe::narrow_klass_shift(), "decode alg wrong");
3916     add(dst, rbase, src, Assembler::LSL, LogKlassAlignmentInBytes);
3917   } else {
3918     add(dst, rbase, src);
3919   }
3920   if (dst == src) reinit_heapbase();
3921 }
3922 
3923 void  MacroAssembler::decode_klass_not_null(Register r) {
3924   decode_klass_not_null(r, r);
3925 }
3926 
3927 void  MacroAssembler::set_narrow_oop(Register dst, jobject obj) {
3928 #ifdef ASSERT
3929   {
3930     ThreadInVMfromUnknown tiv;
3931     assert (UseCompressedOops, "should only be used for compressed oops");
3932     assert (Universe::heap() != NULL, "java heap should be initialized");
3933     assert (oop_recorder() != NULL, "this assembler needs an OopRecorder");
3934     assert(Universe::heap()->is_in_reserved(JNIHandles::resolve(obj)), "should be real oop");
3935   }
3936 #endif
3937   int oop_index = oop_recorder()->find_index(obj);
3938   InstructionMark im(this);
3939   RelocationHolder rspec = oop_Relocation::spec(oop_index);
3940   code_section()->relocate(inst_mark(), rspec);
3941   movz(dst, 0xDEAD, 16);
3942   movk(dst, 0xBEEF);
3943 }
3944 
3945 void  MacroAssembler::set_narrow_klass(Register dst, Klass* k) {
3946   assert (UseCompressedClassPointers, "should only be used for compressed headers");
3947   assert (oop_recorder() != NULL, "this assembler needs an OopRecorder");
3948   int index = oop_recorder()->find_index(k);
3949   assert(! Universe::heap()->is_in_reserved(k), "should not be an oop");
3950 
3951   InstructionMark im(this);
3952   RelocationHolder rspec = metadata_Relocation::spec(index);
3953   code_section()->relocate(inst_mark(), rspec);
3954   narrowKlass nk = Klass::encode_klass(k);
3955   movz(dst, (nk >> 16), 16);
3956   movk(dst, nk & 0xffff);
3957 }
3958 
3959 void MacroAssembler::access_load_at(BasicType type, DecoratorSet decorators,
3960                                     Register dst, Address src,
3961                                     Register tmp1, Register thread_tmp) {
3962   BarrierSetAssembler *bs = BarrierSet::barrier_set()->barrier_set_assembler();
3963   decorators = AccessInternal::decorator_fixup(decorators);
3964   bool as_raw = (decorators & AS_RAW) != 0;
3965   if (as_raw) {
3966     bs->BarrierSetAssembler::load_at(this, decorators, type, dst, src, tmp1, thread_tmp);
3967   } else {
3968     bs->load_at(this, decorators, type, dst, src, tmp1, thread_tmp);
3969   }
3970 }
3971 
3972 void MacroAssembler::access_store_at(BasicType type, DecoratorSet decorators,
3973                                      Address dst, Register src,
3974                                      Register tmp1, Register thread_tmp) {
3975   BarrierSetAssembler *bs = BarrierSet::barrier_set()->barrier_set_assembler();
3976   decorators = AccessInternal::decorator_fixup(decorators);
3977   bool as_raw = (decorators & AS_RAW) != 0;
3978   if (as_raw) {
3979     bs->BarrierSetAssembler::store_at(this, decorators, type, dst, src, tmp1, thread_tmp);
3980   } else {
3981     bs->store_at(this, decorators, type, dst, src, tmp1, thread_tmp);
3982   }
3983 }
3984 
3985 void MacroAssembler::load_heap_oop(Register dst, Address src, Register tmp1,
3986                                    Register thread_tmp, DecoratorSet decorators) {
3987   access_load_at(T_OBJECT, IN_HEAP | decorators, dst, src, tmp1, thread_tmp);
3988 }
3989 
3990 void MacroAssembler::load_heap_oop_not_null(Register dst, Address src, Register tmp1,
3991                                             Register thread_tmp, DecoratorSet decorators) {
3992   access_load_at(T_OBJECT, IN_HEAP | IS_NOT_NULL | decorators, dst, src, tmp1, thread_tmp);
3993 }
3994 
3995 void MacroAssembler::store_heap_oop(Address dst, Register src, Register tmp1,
3996                                     Register thread_tmp, DecoratorSet decorators) {
3997   access_store_at(T_OBJECT, IN_HEAP | decorators, dst, src, tmp1, thread_tmp);
3998 }
3999 
4000 // Used for storing NULLs.
4001 void MacroAssembler::store_heap_oop_null(Address dst) {
4002   access_store_at(T_OBJECT, IN_HEAP, dst, noreg, noreg, noreg);
4003 }
4004 
4005 Address MacroAssembler::allocate_metadata_address(Metadata* obj) {
4006   assert(oop_recorder() != NULL, "this assembler needs a Recorder");
4007   int index = oop_recorder()->allocate_metadata_index(obj);
4008   RelocationHolder rspec = metadata_Relocation::spec(index);
4009   return Address((address)obj, rspec);
4010 }
4011 
4012 // Move an oop into a register.  immediate is true if we want
4013 // immediate instrcutions, i.e. we are not going to patch this
4014 // instruction while the code is being executed by another thread.  In
4015 // that case we can use move immediates rather than the constant pool.
4016 void MacroAssembler::movoop(Register dst, jobject obj, bool immediate) {
4017   int oop_index;
4018   if (obj == NULL) {
4019     oop_index = oop_recorder()->allocate_oop_index(obj);
4020   } else {
4021 #ifdef ASSERT
4022     {
4023       ThreadInVMfromUnknown tiv;
4024       assert(Universe::heap()->is_in_reserved(JNIHandles::resolve(obj)), "should be real oop");
4025     }
4026 #endif
4027     oop_index = oop_recorder()->find_index(obj);
4028   }
4029   RelocationHolder rspec = oop_Relocation::spec(oop_index);
4030   if (! immediate) {
4031     address dummy = address(uintptr_t(pc()) & -wordSize); // A nearby aligned address
4032     ldr_constant(dst, Address(dummy, rspec));
4033   } else
4034     mov(dst, Address((address)obj, rspec));
4035 }
4036 
4037 // Move a metadata address into a register.
4038 void MacroAssembler::mov_metadata(Register dst, Metadata* obj) {
4039   int oop_index;
4040   if (obj == NULL) {
4041     oop_index = oop_recorder()->allocate_metadata_index(obj);
4042   } else {
4043     oop_index = oop_recorder()->find_index(obj);
4044   }
4045   RelocationHolder rspec = metadata_Relocation::spec(oop_index);
4046   mov(dst, Address((address)obj, rspec));
4047 }
4048 
4049 Address MacroAssembler::constant_oop_address(jobject obj) {
4050 #ifdef ASSERT
4051   {
4052     ThreadInVMfromUnknown tiv;
4053     assert(oop_recorder() != NULL, "this assembler needs an OopRecorder");
4054     assert(Universe::heap()->is_in_reserved(JNIHandles::resolve(obj)), "not an oop");
4055   }
4056 #endif
4057   int oop_index = oop_recorder()->find_index(obj);
4058   return Address((address)obj, oop_Relocation::spec(oop_index));
4059 }
4060 
4061 // Defines obj, preserves var_size_in_bytes, okay for t2 == var_size_in_bytes.
4062 void MacroAssembler::tlab_allocate(Register obj,
4063                                    Register var_size_in_bytes,
4064                                    int con_size_in_bytes,
4065                                    Register t1,
4066                                    Register t2,
4067                                    Label& slow_case) {
4068   BarrierSetAssembler *bs = BarrierSet::barrier_set()->barrier_set_assembler();
4069   bs->tlab_allocate(this, obj, var_size_in_bytes, con_size_in_bytes, t1, t2, slow_case);
4070 }
4071 
4072 // Defines obj, preserves var_size_in_bytes
4073 void MacroAssembler::eden_allocate(Register obj,
4074                                    Register var_size_in_bytes,
4075                                    int con_size_in_bytes,
4076                                    Register t1,
4077                                    Label& slow_case) {
4078   BarrierSetAssembler *bs = BarrierSet::barrier_set()->barrier_set_assembler();
4079   bs->eden_allocate(this, obj, var_size_in_bytes, con_size_in_bytes, t1, slow_case);
4080 }
4081 
4082 // Zero words; len is in bytes
4083 // Destroys all registers except addr
4084 // len must be a nonzero multiple of wordSize
4085 void MacroAssembler::zero_memory(Register addr, Register len, Register t1) {
4086   assert_different_registers(addr, len, t1, rscratch1, rscratch2);
4087 
4088 #ifdef ASSERT
4089   { Label L;
4090     tst(len, BytesPerWord - 1);
4091     br(Assembler::EQ, L);
4092     stop("len is not a multiple of BytesPerWord");
4093     bind(L);
4094   }
4095 #endif
4096 
4097 #ifndef PRODUCT
4098   block_comment("zero memory");
4099 #endif
4100 
4101   Label loop;
4102   Label entry;
4103 
4104 //  Algorithm:
4105 //
4106 //    scratch1 = cnt & 7;
4107 //    cnt -= scratch1;
4108 //    p += scratch1;
4109 //    switch (scratch1) {
4110 //      do {
4111 //        cnt -= 8;
4112 //          p[-8] = 0;
4113 //        case 7:
4114 //          p[-7] = 0;
4115 //        case 6:
4116 //          p[-6] = 0;
4117 //          // ...
4118 //        case 1:
4119 //          p[-1] = 0;
4120 //        case 0:
4121 //          p += 8;
4122 //      } while (cnt);
4123 //    }
4124 
4125   const int unroll = 8; // Number of str(zr) instructions we'll unroll
4126 
4127   lsr(len, len, LogBytesPerWord);
4128   andr(rscratch1, len, unroll - 1);  // tmp1 = cnt % unroll
4129   sub(len, len, rscratch1);      // cnt -= unroll
4130   // t1 always points to the end of the region we're about to zero
4131   add(t1, addr, rscratch1, Assembler::LSL, LogBytesPerWord);
4132   adr(rscratch2, entry);
4133   sub(rscratch2, rscratch2, rscratch1, Assembler::LSL, 2);
4134   br(rscratch2);
4135   bind(loop);
4136   sub(len, len, unroll);
4137   for (int i = -unroll; i < 0; i++)
4138     Assembler::str(zr, Address(t1, i * wordSize));
4139   bind(entry);
4140   add(t1, t1, unroll * wordSize);
4141   cbnz(len, loop);
4142 }
4143 
4144 void MacroAssembler::verify_tlab() {
4145 #ifdef ASSERT
4146   if (UseTLAB && VerifyOops) {
4147     Label next, ok;
4148 
4149     stp(rscratch2, rscratch1, Address(pre(sp, -16)));
4150 
4151     ldr(rscratch2, Address(rthread, in_bytes(JavaThread::tlab_top_offset())));
4152     ldr(rscratch1, Address(rthread, in_bytes(JavaThread::tlab_start_offset())));
4153     cmp(rscratch2, rscratch1);
4154     br(Assembler::HS, next);
4155     STOP("assert(top >= start)");
4156     should_not_reach_here();
4157 
4158     bind(next);
4159     ldr(rscratch2, Address(rthread, in_bytes(JavaThread::tlab_end_offset())));
4160     ldr(rscratch1, Address(rthread, in_bytes(JavaThread::tlab_top_offset())));
4161     cmp(rscratch2, rscratch1);
4162     br(Assembler::HS, ok);
4163     STOP("assert(top <= end)");
4164     should_not_reach_here();
4165 
4166     bind(ok);
4167     ldp(rscratch2, rscratch1, Address(post(sp, 16)));
4168   }
4169 #endif
4170 }
4171 
4172 // Writes to stack successive pages until offset reached to check for
4173 // stack overflow + shadow pages.  This clobbers tmp.
4174 void MacroAssembler::bang_stack_size(Register size, Register tmp) {
4175   assert_different_registers(tmp, size, rscratch1);
4176   mov(tmp, sp);
4177   // Bang stack for total size given plus shadow page size.
4178   // Bang one page at a time because large size can bang beyond yellow and
4179   // red zones.
4180   Label loop;
4181   mov(rscratch1, os::vm_page_size());
4182   bind(loop);
4183   lea(tmp, Address(tmp, -os::vm_page_size()));
4184   subsw(size, size, rscratch1);
4185   str(size, Address(tmp));
4186   br(Assembler::GT, loop);
4187 
4188   // Bang down shadow pages too.
4189   // At this point, (tmp-0) is the last address touched, so don't
4190   // touch it again.  (It was touched as (tmp-pagesize) but then tmp
4191   // was post-decremented.)  Skip this address by starting at i=1, and
4192   // touch a few more pages below.  N.B.  It is important to touch all
4193   // the way down to and including i=StackShadowPages.
4194   for (int i = 0; i < (int)(JavaThread::stack_shadow_zone_size() / os::vm_page_size()) - 1; i++) {
4195     // this could be any sized move but this is can be a debugging crumb
4196     // so the bigger the better.
4197     lea(tmp, Address(tmp, -os::vm_page_size()));
4198     str(size, Address(tmp));
4199   }
4200 }
4201 
4202 
4203 // Move the address of the polling page into dest.
4204 void MacroAssembler::get_polling_page(Register dest, address page, relocInfo::relocType rtype) {
4205   if (SafepointMechanism::uses_thread_local_poll()) {
4206     ldr(dest, Address(rthread, Thread::polling_page_offset()));
4207   } else {
4208     unsigned long off;
4209     adrp(dest, Address(page, rtype), off);
4210     assert(off == 0, "polling page must be page aligned");
4211   }
4212 }
4213 
4214 // Move the address of the polling page into r, then read the polling
4215 // page.
4216 address MacroAssembler::read_polling_page(Register r, address page, relocInfo::relocType rtype) {
4217   get_polling_page(r, page, rtype);
4218   return read_polling_page(r, rtype);
4219 }
4220 
4221 // Read the polling page.  The address of the polling page must
4222 // already be in r.
4223 address MacroAssembler::read_polling_page(Register r, relocInfo::relocType rtype) {
4224   InstructionMark im(this);
4225   code_section()->relocate(inst_mark(), rtype);
4226   ldrw(zr, Address(r, 0));
4227   return inst_mark();
4228 }
4229 
4230 void MacroAssembler::adrp(Register reg1, const Address &dest, unsigned long &byte_offset) {
4231   relocInfo::relocType rtype = dest.rspec().reloc()->type();
4232   unsigned long low_page = (unsigned long)CodeCache::low_bound() >> 12;
4233   unsigned long high_page = (unsigned long)(CodeCache::high_bound()-1) >> 12;
4234   unsigned long dest_page = (unsigned long)dest.target() >> 12;
4235   long offset_low = dest_page - low_page;
4236   long offset_high = dest_page - high_page;
4237 
4238   assert(is_valid_AArch64_address(dest.target()), "bad address");
4239   assert(dest.getMode() == Address::literal, "ADRP must be applied to a literal address");
4240 
4241   InstructionMark im(this);
4242   code_section()->relocate(inst_mark(), dest.rspec());
4243   // 8143067: Ensure that the adrp can reach the dest from anywhere within
4244   // the code cache so that if it is relocated we know it will still reach
4245   if (offset_high >= -(1<<20) && offset_low < (1<<20)) {
4246     _adrp(reg1, dest.target());
4247   } else {
4248     unsigned long target = (unsigned long)dest.target();
4249     unsigned long adrp_target
4250       = (target & 0xffffffffUL) | ((unsigned long)pc() & 0xffff00000000UL);
4251 
4252     _adrp(reg1, (address)adrp_target);
4253     movk(reg1, target >> 32, 32);
4254   }
4255   byte_offset = (unsigned long)dest.target() & 0xfff;
4256 }
4257 
4258 void MacroAssembler::load_byte_map_base(Register reg) {
4259   jbyte *byte_map_base =
4260     ((CardTableBarrierSet*)(BarrierSet::barrier_set()))->card_table()->byte_map_base();
4261 
4262   if (is_valid_AArch64_address((address)byte_map_base)) {
4263     // Strictly speaking the byte_map_base isn't an address at all,
4264     // and it might even be negative.
4265     unsigned long offset;
4266     adrp(reg, ExternalAddress((address)byte_map_base), offset);
4267     // We expect offset to be zero with most collectors.
4268     if (offset != 0) {
4269       add(reg, reg, offset);
4270     }
4271   } else {
4272     mov(reg, (uint64_t)byte_map_base);
4273   }
4274 }
4275 
4276 void MacroAssembler::build_frame(int framesize) {
4277   assert(framesize > 0, "framesize must be > 0");
4278   if (framesize < ((1 << 9) + 2 * wordSize)) {
4279     sub(sp, sp, framesize);
4280     stp(rfp, lr, Address(sp, framesize - 2 * wordSize));
4281     if (PreserveFramePointer) add(rfp, sp, framesize - 2 * wordSize);
4282   } else {
4283     stp(rfp, lr, Address(pre(sp, -2 * wordSize)));
4284     if (PreserveFramePointer) mov(rfp, sp);
4285     if (framesize < ((1 << 12) + 2 * wordSize))
4286       sub(sp, sp, framesize - 2 * wordSize);
4287     else {
4288       mov(rscratch1, framesize - 2 * wordSize);
4289       sub(sp, sp, rscratch1);
4290     }
4291   }
4292 }
4293 
4294 void MacroAssembler::remove_frame(int framesize) {
4295   assert(framesize > 0, "framesize must be > 0");
4296   if (framesize < ((1 << 9) + 2 * wordSize)) {
4297     ldp(rfp, lr, Address(sp, framesize - 2 * wordSize));
4298     add(sp, sp, framesize);
4299   } else {
4300     if (framesize < ((1 << 12) + 2 * wordSize))
4301       add(sp, sp, framesize - 2 * wordSize);
4302     else {
4303       mov(rscratch1, framesize - 2 * wordSize);
4304       add(sp, sp, rscratch1);
4305     }
4306     ldp(rfp, lr, Address(post(sp, 2 * wordSize)));
4307   }
4308 }
4309 
4310 typedef void (MacroAssembler::* chr_insn)(Register Rt, const Address &adr);
4311 
4312 // Search for str1 in str2 and return index or -1
4313 void MacroAssembler::string_indexof(Register str2, Register str1,
4314                                     Register cnt2, Register cnt1,
4315                                     Register tmp1, Register tmp2,
4316                                     Register tmp3, Register tmp4,
4317                                     int icnt1, Register result, int ae) {
4318   Label BM, LINEARSEARCH, DONE, NOMATCH, MATCH;
4319 
4320   Register ch1 = rscratch1;
4321   Register ch2 = rscratch2;
4322   Register cnt1tmp = tmp1;
4323   Register cnt2tmp = tmp2;
4324   Register cnt1_neg = cnt1;
4325   Register cnt2_neg = cnt2;
4326   Register result_tmp = tmp4;
4327 
4328   bool isL = ae == StrIntrinsicNode::LL;
4329 
4330   bool str1_isL = ae == StrIntrinsicNode::LL || ae == StrIntrinsicNode::UL;
4331   bool str2_isL = ae == StrIntrinsicNode::LL || ae == StrIntrinsicNode::LU;
4332   int str1_chr_shift = str1_isL ? 0:1;
4333   int str2_chr_shift = str2_isL ? 0:1;
4334   int str1_chr_size = str1_isL ? 1:2;
4335   int str2_chr_size = str2_isL ? 1:2;
4336   chr_insn str1_load_1chr = str1_isL ? (chr_insn)&MacroAssembler::ldrb :
4337                                       (chr_insn)&MacroAssembler::ldrh;
4338   chr_insn str2_load_1chr = str2_isL ? (chr_insn)&MacroAssembler::ldrb :
4339                                       (chr_insn)&MacroAssembler::ldrh;
4340   chr_insn load_2chr = isL ? (chr_insn)&MacroAssembler::ldrh : (chr_insn)&MacroAssembler::ldrw;
4341   chr_insn load_4chr = isL ? (chr_insn)&MacroAssembler::ldrw : (chr_insn)&MacroAssembler::ldr;
4342 
4343   // Note, inline_string_indexOf() generates checks:
4344   // if (substr.count > string.count) return -1;
4345   // if (substr.count == 0) return 0;
4346 
4347 // We have two strings, a source string in str2, cnt2 and a pattern string
4348 // in str1, cnt1. Find the 1st occurence of pattern in source or return -1.
4349 
4350 // For larger pattern and source we use a simplified Boyer Moore algorithm.
4351 // With a small pattern and source we use linear scan.
4352 
4353   if (icnt1 == -1) {
4354     cmp(cnt1, 256);             // Use Linear Scan if cnt1 < 8 || cnt1 >= 256
4355     ccmp(cnt1, 8, 0b0000, LO);  // Can't handle skip >= 256 because we use
4356     br(LO, LINEARSEARCH);       // a byte array.
4357     cmp(cnt1, cnt2, LSR, 2);    // Source must be 4 * pattern for BM
4358     br(HS, LINEARSEARCH);
4359   }
4360 
4361 // The Boyer Moore alogorithm is based on the description here:-
4362 //
4363 // http://en.wikipedia.org/wiki/Boyer%E2%80%93Moore_string_search_algorithm
4364 //
4365 // This describes and algorithm with 2 shift rules. The 'Bad Character' rule
4366 // and the 'Good Suffix' rule.
4367 //
4368 // These rules are essentially heuristics for how far we can shift the
4369 // pattern along the search string.
4370 //
4371 // The implementation here uses the 'Bad Character' rule only because of the
4372 // complexity of initialisation for the 'Good Suffix' rule.
4373 //
4374 // This is also known as the Boyer-Moore-Horspool algorithm:-
4375 //
4376 // http://en.wikipedia.org/wiki/Boyer-Moore-Horspool_algorithm
4377 //
4378 // #define ASIZE 128
4379 //
4380 //    int bm(unsigned char *x, int m, unsigned char *y, int n) {
4381 //       int i, j;
4382 //       unsigned c;
4383 //       unsigned char bc[ASIZE];
4384 //
4385 //       /* Preprocessing */
4386 //       for (i = 0; i < ASIZE; ++i)
4387 //          bc[i] = 0;
4388 //       for (i = 0; i < m - 1; ) {
4389 //          c = x[i];
4390 //          ++i;
4391 //          if (c < ASIZE) bc[c] = i;
4392 //       }
4393 //
4394 //       /* Searching */
4395 //       j = 0;
4396 //       while (j <= n - m) {
4397 //          c = y[i+j];
4398 //          if (x[m-1] == c)
4399 //            for (i = m - 2; i >= 0 && x[i] == y[i + j]; --i);
4400 //          if (i < 0) return j;
4401 //          if (c < ASIZE)
4402 //            j = j - bc[y[j+m-1]] + m;
4403 //          else
4404 //            j += 1; // Advance by 1 only if char >= ASIZE
4405 //       }
4406 //    }
4407 
4408   if (icnt1 == -1) {
4409     BIND(BM);
4410 
4411     Label ZLOOP, BCLOOP, BCSKIP, BMLOOPSTR2, BMLOOPSTR1, BMSKIP;
4412     Label BMADV, BMMATCH, BMCHECKEND;
4413 
4414     Register cnt1end = tmp2;
4415     Register str2end = cnt2;
4416     Register skipch = tmp2;
4417 
4418     // Restrict ASIZE to 128 to reduce stack space/initialisation.
4419     // The presence of chars >= ASIZE in the target string does not affect
4420     // performance, but we must be careful not to initialise them in the stack
4421     // array.
4422     // The presence of chars >= ASIZE in the source string may adversely affect
4423     // performance since we can only advance by one when we encounter one.
4424 
4425       stp(zr, zr, pre(sp, -128));
4426       for (int i = 1; i < 8; i++)
4427           stp(zr, zr, Address(sp, i*16));
4428 
4429       mov(cnt1tmp, 0);
4430       sub(cnt1end, cnt1, 1);
4431     BIND(BCLOOP);
4432       (this->*str1_load_1chr)(ch1, Address(str1, cnt1tmp, Address::lsl(str1_chr_shift)));
4433       cmp(ch1, 128);
4434       add(cnt1tmp, cnt1tmp, 1);
4435       br(HS, BCSKIP);
4436       strb(cnt1tmp, Address(sp, ch1));
4437     BIND(BCSKIP);
4438       cmp(cnt1tmp, cnt1end);
4439       br(LT, BCLOOP);
4440 
4441       mov(result_tmp, str2);
4442 
4443       sub(cnt2, cnt2, cnt1);
4444       add(str2end, str2, cnt2, LSL, str2_chr_shift);
4445     BIND(BMLOOPSTR2);
4446       sub(cnt1tmp, cnt1, 1);
4447       (this->*str1_load_1chr)(ch1, Address(str1, cnt1tmp, Address::lsl(str1_chr_shift)));
4448       (this->*str2_load_1chr)(skipch, Address(str2, cnt1tmp, Address::lsl(str2_chr_shift)));
4449       cmp(ch1, skipch);
4450       br(NE, BMSKIP);
4451       subs(cnt1tmp, cnt1tmp, 1);
4452       br(LT, BMMATCH);
4453     BIND(BMLOOPSTR1);
4454       (this->*str1_load_1chr)(ch1, Address(str1, cnt1tmp, Address::lsl(str1_chr_shift)));
4455       (this->*str2_load_1chr)(ch2, Address(str2, cnt1tmp, Address::lsl(str2_chr_shift)));
4456       cmp(ch1, ch2);
4457       br(NE, BMSKIP);
4458       subs(cnt1tmp, cnt1tmp, 1);
4459       br(GE, BMLOOPSTR1);
4460     BIND(BMMATCH);
4461       sub(result, str2, result_tmp);
4462       if (!str2_isL) lsr(result, result, 1);
4463       add(sp, sp, 128);
4464       b(DONE);
4465     BIND(BMADV);
4466       add(str2, str2, str2_chr_size);
4467       b(BMCHECKEND);
4468     BIND(BMSKIP);
4469       cmp(skipch, 128);
4470       br(HS, BMADV);
4471       ldrb(ch2, Address(sp, skipch));
4472       add(str2, str2, cnt1, LSL, str2_chr_shift);
4473       sub(str2, str2, ch2, LSL, str2_chr_shift);
4474     BIND(BMCHECKEND);
4475       cmp(str2, str2end);
4476       br(LE, BMLOOPSTR2);
4477       add(sp, sp, 128);
4478       b(NOMATCH);
4479   }
4480 
4481   BIND(LINEARSEARCH);
4482   {
4483     Label DO1, DO2, DO3;
4484 
4485     Register str2tmp = tmp2;
4486     Register first = tmp3;
4487 
4488     if (icnt1 == -1)
4489     {
4490         Label DOSHORT, FIRST_LOOP, STR2_NEXT, STR1_LOOP, STR1_NEXT;
4491 
4492         cmp(cnt1, str1_isL == str2_isL ? 4 : 2);
4493         br(LT, DOSHORT);
4494 
4495         sub(cnt2, cnt2, cnt1);
4496         mov(result_tmp, cnt2);
4497 
4498         lea(str1, Address(str1, cnt1, Address::lsl(str1_chr_shift)));
4499         lea(str2, Address(str2, cnt2, Address::lsl(str2_chr_shift)));
4500         sub(cnt1_neg, zr, cnt1, LSL, str1_chr_shift);
4501         sub(cnt2_neg, zr, cnt2, LSL, str2_chr_shift);
4502         (this->*str1_load_1chr)(first, Address(str1, cnt1_neg));
4503 
4504       BIND(FIRST_LOOP);
4505         (this->*str2_load_1chr)(ch2, Address(str2, cnt2_neg));
4506         cmp(first, ch2);
4507         br(EQ, STR1_LOOP);
4508       BIND(STR2_NEXT);
4509         adds(cnt2_neg, cnt2_neg, str2_chr_size);
4510         br(LE, FIRST_LOOP);
4511         b(NOMATCH);
4512 
4513       BIND(STR1_LOOP);
4514         adds(cnt1tmp, cnt1_neg, str1_chr_size);
4515         add(cnt2tmp, cnt2_neg, str2_chr_size);
4516         br(GE, MATCH);
4517 
4518       BIND(STR1_NEXT);
4519         (this->*str1_load_1chr)(ch1, Address(str1, cnt1tmp));
4520         (this->*str2_load_1chr)(ch2, Address(str2, cnt2tmp));
4521         cmp(ch1, ch2);
4522         br(NE, STR2_NEXT);
4523         adds(cnt1tmp, cnt1tmp, str1_chr_size);
4524         add(cnt2tmp, cnt2tmp, str2_chr_size);
4525         br(LT, STR1_NEXT);
4526         b(MATCH);
4527 
4528       BIND(DOSHORT);
4529       if (str1_isL == str2_isL) {
4530         cmp(cnt1, 2);
4531         br(LT, DO1);
4532         br(GT, DO3);
4533       }
4534     }
4535 
4536     if (icnt1 == 4) {
4537       Label CH1_LOOP;
4538 
4539         (this->*load_4chr)(ch1, str1);
4540         sub(cnt2, cnt2, 4);
4541         mov(result_tmp, cnt2);
4542         lea(str2, Address(str2, cnt2, Address::lsl(str2_chr_shift)));
4543         sub(cnt2_neg, zr, cnt2, LSL, str2_chr_shift);
4544 
4545       BIND(CH1_LOOP);
4546         (this->*load_4chr)(ch2, Address(str2, cnt2_neg));
4547         cmp(ch1, ch2);
4548         br(EQ, MATCH);
4549         adds(cnt2_neg, cnt2_neg, str2_chr_size);
4550         br(LE, CH1_LOOP);
4551         b(NOMATCH);
4552     }
4553 
4554     if ((icnt1 == -1 && str1_isL == str2_isL) || icnt1 == 2) {
4555       Label CH1_LOOP;
4556 
4557       BIND(DO2);
4558         (this->*load_2chr)(ch1, str1);
4559         sub(cnt2, cnt2, 2);
4560         mov(result_tmp, cnt2);
4561         lea(str2, Address(str2, cnt2, Address::lsl(str2_chr_shift)));
4562         sub(cnt2_neg, zr, cnt2, LSL, str2_chr_shift);
4563 
4564       BIND(CH1_LOOP);
4565         (this->*load_2chr)(ch2, Address(str2, cnt2_neg));
4566         cmp(ch1, ch2);
4567         br(EQ, MATCH);
4568         adds(cnt2_neg, cnt2_neg, str2_chr_size);
4569         br(LE, CH1_LOOP);
4570         b(NOMATCH);
4571     }
4572 
4573     if ((icnt1 == -1 && str1_isL == str2_isL) || icnt1 == 3) {
4574       Label FIRST_LOOP, STR2_NEXT, STR1_LOOP;
4575 
4576       BIND(DO3);
4577         (this->*load_2chr)(first, str1);
4578         (this->*str1_load_1chr)(ch1, Address(str1, 2*str1_chr_size));
4579 
4580         sub(cnt2, cnt2, 3);
4581         mov(result_tmp, cnt2);
4582         lea(str2, Address(str2, cnt2, Address::lsl(str2_chr_shift)));
4583         sub(cnt2_neg, zr, cnt2, LSL, str2_chr_shift);
4584 
4585       BIND(FIRST_LOOP);
4586         (this->*load_2chr)(ch2, Address(str2, cnt2_neg));
4587         cmpw(first, ch2);
4588         br(EQ, STR1_LOOP);
4589       BIND(STR2_NEXT);
4590         adds(cnt2_neg, cnt2_neg, str2_chr_size);
4591         br(LE, FIRST_LOOP);
4592         b(NOMATCH);
4593 
4594       BIND(STR1_LOOP);
4595         add(cnt2tmp, cnt2_neg, 2*str2_chr_size);
4596         (this->*str2_load_1chr)(ch2, Address(str2, cnt2tmp));
4597         cmp(ch1, ch2);
4598         br(NE, STR2_NEXT);
4599         b(MATCH);
4600     }
4601 
4602     if (icnt1 == -1 || icnt1 == 1) {
4603       Label CH1_LOOP, HAS_ZERO;
4604       Label DO1_SHORT, DO1_LOOP;
4605 
4606       BIND(DO1);
4607         (this->*str1_load_1chr)(ch1, str1);
4608         cmp(cnt2, 8);
4609         br(LT, DO1_SHORT);
4610 
4611         if (str2_isL) {
4612           if (!str1_isL) {
4613             tst(ch1, 0xff00);
4614             br(NE, NOMATCH);
4615           }
4616           orr(ch1, ch1, ch1, LSL, 8);
4617         }
4618         orr(ch1, ch1, ch1, LSL, 16);
4619         orr(ch1, ch1, ch1, LSL, 32);
4620 
4621         sub(cnt2, cnt2, 8/str2_chr_size);
4622         mov(result_tmp, cnt2);
4623         lea(str2, Address(str2, cnt2, Address::lsl(str2_chr_shift)));
4624         sub(cnt2_neg, zr, cnt2, LSL, str2_chr_shift);
4625 
4626         mov(tmp3, str2_isL ? 0x0101010101010101 : 0x0001000100010001);
4627       BIND(CH1_LOOP);
4628         ldr(ch2, Address(str2, cnt2_neg));
4629         eor(ch2, ch1, ch2);
4630         sub(tmp1, ch2, tmp3);
4631         orr(tmp2, ch2, str2_isL ? 0x7f7f7f7f7f7f7f7f : 0x7fff7fff7fff7fff);
4632         bics(tmp1, tmp1, tmp2);
4633         br(NE, HAS_ZERO);
4634         adds(cnt2_neg, cnt2_neg, 8);
4635         br(LT, CH1_LOOP);
4636 
4637         cmp(cnt2_neg, 8);
4638         mov(cnt2_neg, 0);
4639         br(LT, CH1_LOOP);
4640         b(NOMATCH);
4641 
4642       BIND(HAS_ZERO);
4643         rev(tmp1, tmp1);
4644         clz(tmp1, tmp1);
4645         add(cnt2_neg, cnt2_neg, tmp1, LSR, 3);
4646         b(MATCH);
4647 
4648       BIND(DO1_SHORT);
4649         mov(result_tmp, cnt2);
4650         lea(str2, Address(str2, cnt2, Address::lsl(str2_chr_shift)));
4651         sub(cnt2_neg, zr, cnt2, LSL, str2_chr_shift);
4652       BIND(DO1_LOOP);
4653         (this->*str2_load_1chr)(ch2, Address(str2, cnt2_neg));
4654         cmpw(ch1, ch2);
4655         br(EQ, MATCH);
4656         adds(cnt2_neg, cnt2_neg, str2_chr_size);
4657         br(LT, DO1_LOOP);
4658     }
4659   }
4660   BIND(NOMATCH);
4661     mov(result, -1);
4662     b(DONE);
4663   BIND(MATCH);
4664     add(result, result_tmp, cnt2_neg, ASR, str2_chr_shift);
4665   BIND(DONE);
4666 }
4667 
4668 typedef void (MacroAssembler::* chr_insn)(Register Rt, const Address &adr);
4669 typedef void (MacroAssembler::* uxt_insn)(Register Rd, Register Rn);
4670 
4671 void MacroAssembler::string_indexof_char(Register str1, Register cnt1,
4672                                          Register ch, Register result,
4673                                          Register tmp1, Register tmp2, Register tmp3)
4674 {
4675   Label CH1_LOOP, HAS_ZERO, DO1_SHORT, DO1_LOOP, MATCH, NOMATCH, DONE;
4676   Register cnt1_neg = cnt1;
4677   Register ch1 = rscratch1;
4678   Register result_tmp = rscratch2;
4679 
4680   cmp(cnt1, 4);
4681   br(LT, DO1_SHORT);
4682 
4683   orr(ch, ch, ch, LSL, 16);
4684   orr(ch, ch, ch, LSL, 32);
4685 
4686   sub(cnt1, cnt1, 4);
4687   mov(result_tmp, cnt1);
4688   lea(str1, Address(str1, cnt1, Address::uxtw(1)));
4689   sub(cnt1_neg, zr, cnt1, LSL, 1);
4690 
4691   mov(tmp3, 0x0001000100010001);
4692 
4693   BIND(CH1_LOOP);
4694     ldr(ch1, Address(str1, cnt1_neg));
4695     eor(ch1, ch, ch1);
4696     sub(tmp1, ch1, tmp3);
4697     orr(tmp2, ch1, 0x7fff7fff7fff7fff);
4698     bics(tmp1, tmp1, tmp2);
4699     br(NE, HAS_ZERO);
4700     adds(cnt1_neg, cnt1_neg, 8);
4701     br(LT, CH1_LOOP);
4702 
4703     cmp(cnt1_neg, 8);
4704     mov(cnt1_neg, 0);
4705     br(LT, CH1_LOOP);
4706     b(NOMATCH);
4707 
4708   BIND(HAS_ZERO);
4709     rev(tmp1, tmp1);
4710     clz(tmp1, tmp1);
4711     add(cnt1_neg, cnt1_neg, tmp1, LSR, 3);
4712     b(MATCH);
4713 
4714   BIND(DO1_SHORT);
4715     mov(result_tmp, cnt1);
4716     lea(str1, Address(str1, cnt1, Address::uxtw(1)));
4717     sub(cnt1_neg, zr, cnt1, LSL, 1);
4718   BIND(DO1_LOOP);
4719     ldrh(ch1, Address(str1, cnt1_neg));
4720     cmpw(ch, ch1);
4721     br(EQ, MATCH);
4722     adds(cnt1_neg, cnt1_neg, 2);
4723     br(LT, DO1_LOOP);
4724   BIND(NOMATCH);
4725     mov(result, -1);
4726     b(DONE);
4727   BIND(MATCH);
4728     add(result, result_tmp, cnt1_neg, ASR, 1);
4729   BIND(DONE);
4730 }
4731 
4732 // Compare strings.
4733 void MacroAssembler::string_compare(Register str1, Register str2,
4734                                     Register cnt1, Register cnt2, Register result,
4735                                     Register tmp1,
4736                                     FloatRegister vtmp, FloatRegister vtmpZ, int ae) {
4737   Label LENGTH_DIFF, DONE, SHORT_LOOP, SHORT_STRING,
4738     NEXT_WORD, DIFFERENCE;
4739 
4740   bool isLL = ae == StrIntrinsicNode::LL;
4741   bool isLU = ae == StrIntrinsicNode::LU;
4742   bool isUL = ae == StrIntrinsicNode::UL;
4743 
4744   bool str1_isL = isLL || isLU;
4745   bool str2_isL = isLL || isUL;
4746 
4747   int str1_chr_shift = str1_isL ? 0 : 1;
4748   int str2_chr_shift = str2_isL ? 0 : 1;
4749   int str1_chr_size = str1_isL ? 1 : 2;
4750   int str2_chr_size = str2_isL ? 1 : 2;
4751 
4752   chr_insn str1_load_chr = str1_isL ? (chr_insn)&MacroAssembler::ldrb :
4753                                       (chr_insn)&MacroAssembler::ldrh;
4754   chr_insn str2_load_chr = str2_isL ? (chr_insn)&MacroAssembler::ldrb :
4755                                       (chr_insn)&MacroAssembler::ldrh;
4756   uxt_insn ext_chr = isLL ? (uxt_insn)&MacroAssembler::uxtbw :
4757                             (uxt_insn)&MacroAssembler::uxthw;
4758 
4759   BLOCK_COMMENT("string_compare {");
4760 
4761   // Bizzarely, the counts are passed in bytes, regardless of whether they
4762   // are L or U strings, however the result is always in characters.
4763   if (!str1_isL) asrw(cnt1, cnt1, 1);
4764   if (!str2_isL) asrw(cnt2, cnt2, 1);
4765 
4766   // Compute the minimum of the string lengths and save the difference.
4767   subsw(tmp1, cnt1, cnt2);
4768   cselw(cnt2, cnt1, cnt2, Assembler::LE); // min
4769 
4770   // A very short string
4771   cmpw(cnt2, isLL ? 8:4);
4772   br(Assembler::LT, SHORT_STRING);
4773 
4774   // Check if the strings start at the same location.
4775   cmp(str1, str2);
4776   br(Assembler::EQ, LENGTH_DIFF);
4777 
4778   // Compare longwords
4779   {
4780     subw(cnt2, cnt2, isLL ? 8:4); // The last longword is a special case
4781 
4782     // Move both string pointers to the last longword of their
4783     // strings, negate the remaining count, and convert it to bytes.
4784     lea(str1, Address(str1, cnt2, Address::uxtw(str1_chr_shift)));
4785     lea(str2, Address(str2, cnt2, Address::uxtw(str2_chr_shift)));
4786     if (isLU || isUL) {
4787       sub(cnt1, zr, cnt2, LSL, str1_chr_shift);
4788       eor(vtmpZ, T16B, vtmpZ, vtmpZ);
4789     }
4790     sub(cnt2, zr, cnt2, LSL, str2_chr_shift);
4791 
4792     // Loop, loading longwords and comparing them into rscratch2.
4793     bind(NEXT_WORD);
4794     if (isLU) {
4795       ldrs(vtmp, Address(str1, cnt1));
4796       zip1(vtmp, T8B, vtmp, vtmpZ);
4797       umov(result, vtmp, D, 0);
4798     } else {
4799       ldr(result, Address(str1, isUL ? cnt1:cnt2));
4800     }
4801     if (isUL) {
4802       ldrs(vtmp, Address(str2, cnt2));
4803       zip1(vtmp, T8B, vtmp, vtmpZ);
4804       umov(rscratch1, vtmp, D, 0);
4805     } else {
4806       ldr(rscratch1, Address(str2, cnt2));
4807     }
4808     adds(cnt2, cnt2, isUL ? 4:8);
4809     if (isLU || isUL) add(cnt1, cnt1, isLU ? 4:8);
4810     eor(rscratch2, result, rscratch1);
4811     cbnz(rscratch2, DIFFERENCE);
4812     br(Assembler::LT, NEXT_WORD);
4813 
4814     // Last longword.  In the case where length == 4 we compare the
4815     // same longword twice, but that's still faster than another
4816     // conditional branch.
4817 
4818     if (isLU) {
4819       ldrs(vtmp, Address(str1));
4820       zip1(vtmp, T8B, vtmp, vtmpZ);
4821       umov(result, vtmp, D, 0);
4822     } else {
4823       ldr(result, Address(str1));
4824     }
4825     if (isUL) {
4826       ldrs(vtmp, Address(str2));
4827       zip1(vtmp, T8B, vtmp, vtmpZ);
4828       umov(rscratch1, vtmp, D, 0);
4829     } else {
4830       ldr(rscratch1, Address(str2));
4831     }
4832     eor(rscratch2, result, rscratch1);
4833     cbz(rscratch2, LENGTH_DIFF);
4834 
4835     // Find the first different characters in the longwords and
4836     // compute their difference.
4837     bind(DIFFERENCE);
4838     rev(rscratch2, rscratch2);
4839     clz(rscratch2, rscratch2);
4840     andr(rscratch2, rscratch2, isLL ? -8 : -16);
4841     lsrv(result, result, rscratch2);
4842     (this->*ext_chr)(result, result);
4843     lsrv(rscratch1, rscratch1, rscratch2);
4844     (this->*ext_chr)(rscratch1, rscratch1);
4845     subw(result, result, rscratch1);
4846     b(DONE);
4847   }
4848 
4849   bind(SHORT_STRING);
4850   // Is the minimum length zero?
4851   cbz(cnt2, LENGTH_DIFF);
4852 
4853   bind(SHORT_LOOP);
4854   (this->*str1_load_chr)(result, Address(post(str1, str1_chr_size)));
4855   (this->*str2_load_chr)(cnt1, Address(post(str2, str2_chr_size)));
4856   subw(result, result, cnt1);
4857   cbnz(result, DONE);
4858   sub(cnt2, cnt2, 1);
4859   cbnz(cnt2, SHORT_LOOP);
4860 
4861   // Strings are equal up to min length.  Return the length difference.
4862   bind(LENGTH_DIFF);
4863   mov(result, tmp1);
4864 
4865   // That's it
4866   bind(DONE);
4867 
4868   BLOCK_COMMENT("} string_compare");
4869 }
4870 
4871 // This method checks if provided byte array contains byte with highest bit set.
4872 void MacroAssembler::has_negatives(Register ary1, Register len, Register result) {
4873     // Simple and most common case of aligned small array which is not at the
4874     // end of memory page is placed here. All other cases are in stub.
4875     Label LOOP, END, STUB, STUB_LONG, SET_RESULT, DONE;
4876     const uint64_t UPPER_BIT_MASK=0x8080808080808080;
4877     assert_different_registers(ary1, len, result);
4878 
4879     cmpw(len, 0);
4880     br(LE, SET_RESULT);
4881     cmpw(len, 4 * wordSize);
4882     br(GE, STUB_LONG); // size > 32 then go to stub
4883 
4884     int shift = 64 - exact_log2(os::vm_page_size());
4885     lsl(rscratch1, ary1, shift);
4886     mov(rscratch2, (size_t)(4 * wordSize) << shift);
4887     adds(rscratch2, rscratch1, rscratch2);  // At end of page?
4888     br(CS, STUB); // at the end of page then go to stub
4889     subs(len, len, wordSize);
4890     br(LT, END);
4891 
4892   BIND(LOOP);
4893     ldr(rscratch1, Address(post(ary1, wordSize)));
4894     tst(rscratch1, UPPER_BIT_MASK);
4895     br(NE, SET_RESULT);
4896     subs(len, len, wordSize);
4897     br(GE, LOOP);
4898     cmpw(len, -wordSize);
4899     br(EQ, SET_RESULT);
4900 
4901   BIND(END);
4902     ldr(result, Address(ary1));
4903     sub(len, zr, len, LSL, 3); // LSL 3 is to get bits from bytes
4904     lslv(result, result, len);
4905     tst(result, UPPER_BIT_MASK);
4906     b(SET_RESULT);
4907 
4908   BIND(STUB);
4909     RuntimeAddress has_neg =  RuntimeAddress(StubRoutines::aarch64::has_negatives());
4910     assert(has_neg.target() != NULL, "has_negatives stub has not been generated");
4911     trampoline_call(has_neg);
4912     b(DONE);
4913 
4914   BIND(STUB_LONG);
4915     RuntimeAddress has_neg_long =  RuntimeAddress(
4916             StubRoutines::aarch64::has_negatives_long());
4917     assert(has_neg_long.target() != NULL, "has_negatives stub has not been generated");
4918     trampoline_call(has_neg_long);
4919     b(DONE);
4920 
4921   BIND(SET_RESULT);
4922     cset(result, NE); // set true or false
4923 
4924   BIND(DONE);
4925 }
4926 
4927 void MacroAssembler::arrays_equals(Register a1, Register a2, Register tmp3,
4928                                    Register tmp4, Register tmp5, Register result,
4929                                    Register cnt1, int elem_size) {
4930   Label DONE, SAME;
4931   Register tmp1 = rscratch1;
4932   Register tmp2 = rscratch2;
4933   Register cnt2 = tmp2;  // cnt2 only used in array length compare
4934   int elem_per_word = wordSize/elem_size;
4935   int log_elem_size = exact_log2(elem_size);
4936   int length_offset = arrayOopDesc::length_offset_in_bytes();
4937   int base_offset
4938     = arrayOopDesc::base_offset_in_bytes(elem_size == 2 ? T_CHAR : T_BYTE);
4939   int stubBytesThreshold = 3 * 64 + (UseSIMDForArrayEquals ? 0 : 16);
4940 
4941   assert(elem_size == 1 || elem_size == 2, "must be char or byte");
4942   assert_different_registers(a1, a2, result, cnt1, rscratch1, rscratch2);
4943 
4944 #ifndef PRODUCT
4945   {
4946     const char kind = (elem_size == 2) ? 'U' : 'L';
4947     char comment[64];
4948     snprintf(comment, sizeof comment, "array_equals%c{", kind);
4949     BLOCK_COMMENT(comment);
4950   }
4951 #endif
4952 
4953   // if (a1 == a2)
4954   //     return true;
4955   cmpoop(a1, a2); // May have read barriers for a1 and a2.
4956   br(EQ, SAME);
4957 
4958   if (UseSimpleArrayEquals) {
4959     Label NEXT_WORD, SHORT, TAIL03, TAIL01, A_MIGHT_BE_NULL, A_IS_NOT_NULL;
4960     // if (a1 == null || a2 == null)
4961     //     return false;
4962     // a1 & a2 == 0 means (some-pointer is null) or
4963     // (very-rare-or-even-probably-impossible-pointer-values)
4964     // so, we can save one branch in most cases
4965     tst(a1, a2);
4966     mov(result, false);
4967     br(EQ, A_MIGHT_BE_NULL);
4968     // if (a1.length != a2.length)
4969     //      return false;
4970     bind(A_IS_NOT_NULL);
4971     ldrw(cnt1, Address(a1, length_offset));
4972     ldrw(cnt2, Address(a2, length_offset));
4973     eorw(tmp5, cnt1, cnt2);
4974     cbnzw(tmp5, DONE);
4975     lea(a1, Address(a1, base_offset));
4976     lea(a2, Address(a2, base_offset));
4977     // Check for short strings, i.e. smaller than wordSize.
4978     subs(cnt1, cnt1, elem_per_word);
4979     br(Assembler::LT, SHORT);
4980     // Main 8 byte comparison loop.
4981     bind(NEXT_WORD); {
4982       ldr(tmp1, Address(post(a1, wordSize)));
4983       ldr(tmp2, Address(post(a2, wordSize)));
4984       subs(cnt1, cnt1, elem_per_word);
4985       eor(tmp5, tmp1, tmp2);
4986       cbnz(tmp5, DONE);
4987     } br(GT, NEXT_WORD);
4988     // Last longword.  In the case where length == 4 we compare the
4989     // same longword twice, but that's still faster than another
4990     // conditional branch.
4991     // cnt1 could be 0, -1, -2, -3, -4 for chars; -4 only happens when
4992     // length == 4.
4993     if (log_elem_size > 0)
4994       lsl(cnt1, cnt1, log_elem_size);
4995     ldr(tmp3, Address(a1, cnt1));
4996     ldr(tmp4, Address(a2, cnt1));
4997     eor(tmp5, tmp3, tmp4);
4998     cbnz(tmp5, DONE);
4999     b(SAME);
5000     bind(A_MIGHT_BE_NULL);
5001     // in case both a1 and a2 are not-null, proceed with loads
5002     cbz(a1, DONE);
5003     cbz(a2, DONE);
5004     b(A_IS_NOT_NULL);
5005     bind(SHORT);
5006 
5007     tbz(cnt1, 2 - log_elem_size, TAIL03); // 0-7 bytes left.
5008     {
5009       ldrw(tmp1, Address(post(a1, 4)));
5010       ldrw(tmp2, Address(post(a2, 4)));
5011       eorw(tmp5, tmp1, tmp2);
5012       cbnzw(tmp5, DONE);
5013     }
5014     bind(TAIL03);
5015     tbz(cnt1, 1 - log_elem_size, TAIL01); // 0-3 bytes left.
5016     {
5017       ldrh(tmp3, Address(post(a1, 2)));
5018       ldrh(tmp4, Address(post(a2, 2)));
5019       eorw(tmp5, tmp3, tmp4);
5020       cbnzw(tmp5, DONE);
5021     }
5022     bind(TAIL01);
5023     if (elem_size == 1) { // Only needed when comparing byte arrays.
5024       tbz(cnt1, 0, SAME); // 0-1 bytes left.
5025       {
5026         ldrb(tmp1, a1);
5027         ldrb(tmp2, a2);
5028         eorw(tmp5, tmp1, tmp2);
5029         cbnzw(tmp5, DONE);
5030       }
5031     }
5032   } else {
5033     Label NEXT_DWORD, SHORT, TAIL, TAIL2, STUB, EARLY_OUT,
5034         CSET_EQ, LAST_CHECK;
5035     mov(result, false);
5036     cbz(a1, DONE);
5037     ldrw(cnt1, Address(a1, length_offset));
5038     cbz(a2, DONE);
5039     ldrw(cnt2, Address(a2, length_offset));
5040     // on most CPUs a2 is still "locked"(surprisingly) in ldrw and it's
5041     // faster to perform another branch before comparing a1 and a2
5042     cmp(cnt1, elem_per_word);
5043     br(LE, SHORT); // short or same
5044     ldr(tmp3, Address(pre(a1, base_offset)));
5045     cmp(cnt1, stubBytesThreshold);
5046     br(GE, STUB);
5047     ldr(tmp4, Address(pre(a2, base_offset)));
5048     sub(tmp5, zr, cnt1, LSL, 3 + log_elem_size);
5049     cmp(cnt2, cnt1);
5050     br(NE, DONE);
5051 
5052     // Main 16 byte comparison loop with 2 exits
5053     bind(NEXT_DWORD); {
5054       ldr(tmp1, Address(pre(a1, wordSize)));
5055       ldr(tmp2, Address(pre(a2, wordSize)));
5056       subs(cnt1, cnt1, 2 * elem_per_word);
5057       br(LE, TAIL);
5058       eor(tmp4, tmp3, tmp4);
5059       cbnz(tmp4, DONE);
5060       ldr(tmp3, Address(pre(a1, wordSize)));
5061       ldr(tmp4, Address(pre(a2, wordSize)));
5062       cmp(cnt1, elem_per_word);
5063       br(LE, TAIL2);
5064       cmp(tmp1, tmp2);
5065     } br(EQ, NEXT_DWORD);
5066     b(DONE);
5067 
5068     bind(TAIL);
5069     eor(tmp4, tmp3, tmp4);
5070     eor(tmp2, tmp1, tmp2);
5071     lslv(tmp2, tmp2, tmp5);
5072     orr(tmp5, tmp4, tmp2);
5073     cmp(tmp5, zr);
5074     b(CSET_EQ);
5075 
5076     bind(TAIL2);
5077     eor(tmp2, tmp1, tmp2);
5078     cbnz(tmp2, DONE);
5079     b(LAST_CHECK);
5080 
5081     bind(STUB);
5082     ldr(tmp4, Address(pre(a2, base_offset)));
5083     cmp(cnt2, cnt1);
5084     br(NE, DONE);
5085     if (elem_size == 2) { // convert to byte counter
5086       lsl(cnt1, cnt1, 1);
5087     }
5088     eor(tmp5, tmp3, tmp4);
5089     cbnz(tmp5, DONE);
5090     RuntimeAddress stub = RuntimeAddress(StubRoutines::aarch64::large_array_equals());
5091     assert(stub.target() != NULL, "array_equals_long stub has not been generated");
5092     trampoline_call(stub);
5093     b(DONE);
5094 
5095     bind(EARLY_OUT);
5096     // (a1 != null && a2 == null) || (a1 != null && a2 != null && a1 == a2)
5097     // so, if a2 == null => return false(0), else return true, so we can return a2
5098     mov(result, a2);
5099     b(DONE);
5100     bind(SHORT);
5101     cmp(cnt2, cnt1);
5102     br(NE, DONE);
5103     cbz(cnt1, SAME);
5104     sub(tmp5, zr, cnt1, LSL, 3 + log_elem_size);
5105     ldr(tmp3, Address(a1, base_offset));
5106     ldr(tmp4, Address(a2, base_offset));
5107     bind(LAST_CHECK);
5108     eor(tmp4, tmp3, tmp4);
5109     lslv(tmp5, tmp4, tmp5);
5110     cmp(tmp5, zr);
5111     bind(CSET_EQ);
5112     cset(result, EQ);
5113     b(DONE);
5114   }
5115 
5116   bind(SAME);
5117   mov(result, true);
5118   // That's it.
5119   bind(DONE);
5120 
5121   BLOCK_COMMENT("} array_equals");
5122 }
5123 
5124 // Compare Strings
5125 
5126 // For Strings we're passed the address of the first characters in a1
5127 // and a2 and the length in cnt1.
5128 // elem_size is the element size in bytes: either 1 or 2.
5129 // There are two implementations.  For arrays >= 8 bytes, all
5130 // comparisons (including the final one, which may overlap) are
5131 // performed 8 bytes at a time.  For strings < 8 bytes, we compare a
5132 // halfword, then a short, and then a byte.
5133 
5134 void MacroAssembler::string_equals(Register a1, Register a2,
5135                                    Register result, Register cnt1, int elem_size)
5136 {
5137   Label SAME, DONE, SHORT, NEXT_WORD;
5138   Register tmp1 = rscratch1;
5139   Register tmp2 = rscratch2;
5140   Register cnt2 = tmp2;  // cnt2 only used in array length compare
5141 
5142   assert(elem_size == 1 || elem_size == 2, "must be 2 or 1 byte");
5143   assert_different_registers(a1, a2, result, cnt1, rscratch1, rscratch2);
5144 
5145 #ifndef PRODUCT
5146   {
5147     const char kind = (elem_size == 2) ? 'U' : 'L';
5148     char comment[64];
5149     snprintf(comment, sizeof comment, "{string_equals%c", kind);
5150     BLOCK_COMMENT(comment);
5151   }
5152 #endif
5153 
5154   mov(result, false);
5155 
5156   // Check for short strings, i.e. smaller than wordSize.
5157   subs(cnt1, cnt1, wordSize);
5158   br(Assembler::LT, SHORT);
5159   // Main 8 byte comparison loop.
5160   bind(NEXT_WORD); {
5161     ldr(tmp1, Address(post(a1, wordSize)));
5162     ldr(tmp2, Address(post(a2, wordSize)));
5163     subs(cnt1, cnt1, wordSize);
5164     eor(tmp1, tmp1, tmp2);
5165     cbnz(tmp1, DONE);
5166   } br(GT, NEXT_WORD);
5167   // Last longword.  In the case where length == 4 we compare the
5168   // same longword twice, but that's still faster than another
5169   // conditional branch.
5170   // cnt1 could be 0, -1, -2, -3, -4 for chars; -4 only happens when
5171   // length == 4.
5172   ldr(tmp1, Address(a1, cnt1));
5173   ldr(tmp2, Address(a2, cnt1));
5174   eor(tmp2, tmp1, tmp2);
5175   cbnz(tmp2, DONE);
5176   b(SAME);
5177 
5178   bind(SHORT);
5179   Label TAIL03, TAIL01;
5180 
5181   tbz(cnt1, 2, TAIL03); // 0-7 bytes left.
5182   {
5183     ldrw(tmp1, Address(post(a1, 4)));
5184     ldrw(tmp2, Address(post(a2, 4)));
5185     eorw(tmp1, tmp1, tmp2);
5186     cbnzw(tmp1, DONE);
5187   }
5188   bind(TAIL03);
5189   tbz(cnt1, 1, TAIL01); // 0-3 bytes left.
5190   {
5191     ldrh(tmp1, Address(post(a1, 2)));
5192     ldrh(tmp2, Address(post(a2, 2)));
5193     eorw(tmp1, tmp1, tmp2);
5194     cbnzw(tmp1, DONE);
5195   }
5196   bind(TAIL01);
5197   if (elem_size == 1) { // Only needed when comparing 1-byte elements
5198     tbz(cnt1, 0, SAME); // 0-1 bytes left.
5199     {
5200       ldrb(tmp1, a1);
5201       ldrb(tmp2, a2);
5202       eorw(tmp1, tmp1, tmp2);
5203       cbnzw(tmp1, DONE);
5204     }
5205   }
5206   // Arrays are equal.
5207   bind(SAME);
5208   mov(result, true);
5209 
5210   // That's it.
5211   bind(DONE);
5212   BLOCK_COMMENT("} string_equals");
5213 }
5214 
5215 
5216 // The size of the blocks erased by the zero_blocks stub.  We must
5217 // handle anything smaller than this ourselves in zero_words().
5218 const int MacroAssembler::zero_words_block_size = 8;
5219 
5220 // zero_words() is used by C2 ClearArray patterns.  It is as small as
5221 // possible, handling small word counts locally and delegating
5222 // anything larger to the zero_blocks stub.  It is expanded many times
5223 // in compiled code, so it is important to keep it short.
5224 
5225 // ptr:   Address of a buffer to be zeroed.
5226 // cnt:   Count in HeapWords.
5227 //
5228 // ptr, cnt, rscratch1, and rscratch2 are clobbered.
5229 void MacroAssembler::zero_words(Register ptr, Register cnt)
5230 {
5231   assert(is_power_of_2(zero_words_block_size), "adjust this");
5232   assert(ptr == r10 && cnt == r11, "mismatch in register usage");
5233 
5234   BLOCK_COMMENT("zero_words {");
5235   cmp(cnt, zero_words_block_size);
5236   Label around, done, done16;
5237   br(LO, around);
5238   {
5239     RuntimeAddress zero_blocks =  RuntimeAddress(StubRoutines::aarch64::zero_blocks());
5240     assert(zero_blocks.target() != NULL, "zero_blocks stub has not been generated");
5241     if (StubRoutines::aarch64::complete()) {
5242       trampoline_call(zero_blocks);
5243     } else {
5244       bl(zero_blocks);
5245     }
5246   }
5247   bind(around);
5248   for (int i = zero_words_block_size >> 1; i > 1; i >>= 1) {
5249     Label l;
5250     tbz(cnt, exact_log2(i), l);
5251     for (int j = 0; j < i; j += 2) {
5252       stp(zr, zr, post(ptr, 16));
5253     }
5254     bind(l);
5255   }
5256   {
5257     Label l;
5258     tbz(cnt, 0, l);
5259     str(zr, Address(ptr));
5260     bind(l);
5261   }
5262   BLOCK_COMMENT("} zero_words");
5263 }
5264 
5265 // base:         Address of a buffer to be zeroed, 8 bytes aligned.
5266 // cnt:          Immediate count in HeapWords.
5267 #define SmallArraySize (18 * BytesPerLong)
5268 void MacroAssembler::zero_words(Register base, u_int64_t cnt)
5269 {
5270   BLOCK_COMMENT("zero_words {");
5271   int i = cnt & 1;  // store any odd word to start
5272   if (i) str(zr, Address(base));
5273 
5274   if (cnt <= SmallArraySize / BytesPerLong) {
5275     for (; i < (int)cnt; i += 2)
5276       stp(zr, zr, Address(base, i * wordSize));
5277   } else {
5278     const int unroll = 4; // Number of stp(zr, zr) instructions we'll unroll
5279     int remainder = cnt % (2 * unroll);
5280     for (; i < remainder; i += 2)
5281       stp(zr, zr, Address(base, i * wordSize));
5282 
5283     Label loop;
5284     Register cnt_reg = rscratch1;
5285     Register loop_base = rscratch2;
5286     cnt = cnt - remainder;
5287     mov(cnt_reg, cnt);
5288     // adjust base and prebias by -2 * wordSize so we can pre-increment
5289     add(loop_base, base, (remainder - 2) * wordSize);
5290     bind(loop);
5291     sub(cnt_reg, cnt_reg, 2 * unroll);
5292     for (i = 1; i < unroll; i++)
5293       stp(zr, zr, Address(loop_base, 2 * i * wordSize));
5294     stp(zr, zr, Address(pre(loop_base, 2 * unroll * wordSize)));
5295     cbnz(cnt_reg, loop);
5296   }
5297   BLOCK_COMMENT("} zero_words");
5298 }
5299 
5300 // Zero blocks of memory by using DC ZVA.
5301 //
5302 // Aligns the base address first sufficently for DC ZVA, then uses
5303 // DC ZVA repeatedly for every full block.  cnt is the size to be
5304 // zeroed in HeapWords.  Returns the count of words left to be zeroed
5305 // in cnt.
5306 //
5307 // NOTE: This is intended to be used in the zero_blocks() stub.  If
5308 // you want to use it elsewhere, note that cnt must be >= 2*zva_length.
5309 void MacroAssembler::zero_dcache_blocks(Register base, Register cnt) {
5310   Register tmp = rscratch1;
5311   Register tmp2 = rscratch2;
5312   int zva_length = VM_Version::zva_length();
5313   Label initial_table_end, loop_zva;
5314   Label fini;
5315 
5316   // Base must be 16 byte aligned. If not just return and let caller handle it
5317   tst(base, 0x0f);
5318   br(Assembler::NE, fini);
5319   // Align base with ZVA length.
5320   neg(tmp, base);
5321   andr(tmp, tmp, zva_length - 1);
5322 
5323   // tmp: the number of bytes to be filled to align the base with ZVA length.
5324   add(base, base, tmp);
5325   sub(cnt, cnt, tmp, Assembler::ASR, 3);
5326   adr(tmp2, initial_table_end);
5327   sub(tmp2, tmp2, tmp, Assembler::LSR, 2);
5328   br(tmp2);
5329 
5330   for (int i = -zva_length + 16; i < 0; i += 16)
5331     stp(zr, zr, Address(base, i));
5332   bind(initial_table_end);
5333 
5334   sub(cnt, cnt, zva_length >> 3);
5335   bind(loop_zva);
5336   dc(Assembler::ZVA, base);
5337   subs(cnt, cnt, zva_length >> 3);
5338   add(base, base, zva_length);
5339   br(Assembler::GE, loop_zva);
5340   add(cnt, cnt, zva_length >> 3); // count not zeroed by DC ZVA
5341   bind(fini);
5342 }
5343 
5344 // base:   Address of a buffer to be filled, 8 bytes aligned.
5345 // cnt:    Count in 8-byte unit.
5346 // value:  Value to be filled with.
5347 // base will point to the end of the buffer after filling.
5348 void MacroAssembler::fill_words(Register base, Register cnt, Register value)
5349 {
5350 //  Algorithm:
5351 //
5352 //    scratch1 = cnt & 7;
5353 //    cnt -= scratch1;
5354 //    p += scratch1;
5355 //    switch (scratch1) {
5356 //      do {
5357 //        cnt -= 8;
5358 //          p[-8] = v;
5359 //        case 7:
5360 //          p[-7] = v;
5361 //        case 6:
5362 //          p[-6] = v;
5363 //          // ...
5364 //        case 1:
5365 //          p[-1] = v;
5366 //        case 0:
5367 //          p += 8;
5368 //      } while (cnt);
5369 //    }
5370 
5371   assert_different_registers(base, cnt, value, rscratch1, rscratch2);
5372 
5373   Label fini, skip, entry, loop;
5374   const int unroll = 8; // Number of stp instructions we'll unroll
5375 
5376   cbz(cnt, fini);
5377   tbz(base, 3, skip);
5378   str(value, Address(post(base, 8)));
5379   sub(cnt, cnt, 1);
5380   bind(skip);
5381 
5382   andr(rscratch1, cnt, (unroll-1) * 2);
5383   sub(cnt, cnt, rscratch1);
5384   add(base, base, rscratch1, Assembler::LSL, 3);
5385   adr(rscratch2, entry);
5386   sub(rscratch2, rscratch2, rscratch1, Assembler::LSL, 1);
5387   br(rscratch2);
5388 
5389   bind(loop);
5390   add(base, base, unroll * 16);
5391   for (int i = -unroll; i < 0; i++)
5392     stp(value, value, Address(base, i * 16));
5393   bind(entry);
5394   subs(cnt, cnt, unroll * 2);
5395   br(Assembler::GE, loop);
5396 
5397   tbz(cnt, 0, fini);
5398   str(value, Address(post(base, 8)));
5399   bind(fini);
5400 }
5401 
5402 // Intrinsic for sun/nio/cs/ISO_8859_1$Encoder.implEncodeISOArray and
5403 // java/lang/StringUTF16.compress.
5404 void MacroAssembler::encode_iso_array(Register src, Register dst,
5405                       Register len, Register result,
5406                       FloatRegister Vtmp1, FloatRegister Vtmp2,
5407                       FloatRegister Vtmp3, FloatRegister Vtmp4)
5408 {
5409     Label DONE, SET_RESULT, NEXT_32, NEXT_32_PRFM, LOOP_8, NEXT_8, LOOP_1, NEXT_1,
5410         NEXT_32_START, NEXT_32_PRFM_START;
5411     Register tmp1 = rscratch1, tmp2 = rscratch2;
5412 
5413       mov(result, len); // Save initial len
5414 
5415 #ifndef BUILTIN_SIM
5416       cmp(len, 8); // handle shortest strings first
5417       br(LT, LOOP_1);
5418       cmp(len, 32);
5419       br(LT, NEXT_8);
5420       // The following code uses the SIMD 'uzp1' and 'uzp2' instructions
5421       // to convert chars to bytes
5422       if (SoftwarePrefetchHintDistance >= 0) {
5423         ld1(Vtmp1, Vtmp2, Vtmp3, Vtmp4, T8H, src);
5424         cmp(len, SoftwarePrefetchHintDistance/2 + 16);
5425         br(LE, NEXT_32_START);
5426         b(NEXT_32_PRFM_START);
5427         BIND(NEXT_32_PRFM);
5428           ld1(Vtmp1, Vtmp2, Vtmp3, Vtmp4, T8H, src);
5429         BIND(NEXT_32_PRFM_START);
5430           prfm(Address(src, SoftwarePrefetchHintDistance));
5431           orr(v4, T16B, Vtmp1, Vtmp2);
5432           orr(v5, T16B, Vtmp3, Vtmp4);
5433           uzp1(Vtmp1, T16B, Vtmp1, Vtmp2);
5434           uzp1(Vtmp3, T16B, Vtmp3, Vtmp4);
5435           stpq(Vtmp1, Vtmp3, dst);
5436           uzp2(v5, T16B, v4, v5); // high bytes
5437           umov(tmp2, v5, D, 1);
5438           fmovd(tmp1, v5);
5439           orr(tmp1, tmp1, tmp2);
5440           cbnz(tmp1, LOOP_8);
5441           sub(len, len, 32);
5442           add(dst, dst, 32);
5443           add(src, src, 64);
5444           cmp(len, SoftwarePrefetchHintDistance/2 + 16);
5445           br(GE, NEXT_32_PRFM);
5446           cmp(len, 32);
5447           br(LT, LOOP_8);
5448         BIND(NEXT_32);
5449           ld1(Vtmp1, Vtmp2, Vtmp3, Vtmp4, T8H, src);
5450         BIND(NEXT_32_START);
5451       } else {
5452         BIND(NEXT_32);
5453           ld1(Vtmp1, Vtmp2, Vtmp3, Vtmp4, T8H, src);
5454       }
5455       prfm(Address(src, SoftwarePrefetchHintDistance));
5456       uzp1(v4, T16B, Vtmp1, Vtmp2);
5457       uzp1(v5, T16B, Vtmp3, Vtmp4);
5458       stpq(v4, v5, dst);
5459       orr(Vtmp1, T16B, Vtmp1, Vtmp2);
5460       orr(Vtmp3, T16B, Vtmp3, Vtmp4);
5461       uzp2(Vtmp1, T16B, Vtmp1, Vtmp3); // high bytes
5462       umov(tmp2, Vtmp1, D, 1);
5463       fmovd(tmp1, Vtmp1);
5464       orr(tmp1, tmp1, tmp2);
5465       cbnz(tmp1, LOOP_8);
5466       sub(len, len, 32);
5467       add(dst, dst, 32);
5468       add(src, src, 64);
5469       cmp(len, 32);
5470       br(GE, NEXT_32);
5471       cbz(len, DONE);
5472 
5473     BIND(LOOP_8);
5474       cmp(len, 8);
5475       br(LT, LOOP_1);
5476     BIND(NEXT_8);
5477       ld1(Vtmp1, T8H, src);
5478       uzp1(Vtmp2, T16B, Vtmp1, Vtmp1); // low bytes
5479       uzp2(Vtmp3, T16B, Vtmp1, Vtmp1); // high bytes
5480       strd(Vtmp2, dst);
5481       fmovd(tmp1, Vtmp3);
5482       cbnz(tmp1, NEXT_1);
5483 
5484       sub(len, len, 8);
5485       add(dst, dst, 8);
5486       add(src, src, 16);
5487       cmp(len, 8);
5488       br(GE, NEXT_8);
5489 
5490     BIND(LOOP_1);
5491 #endif
5492     cbz(len, DONE);
5493     BIND(NEXT_1);
5494       ldrh(tmp1, Address(post(src, 2)));
5495       strb(tmp1, Address(post(dst, 1)));
5496       tst(tmp1, 0xff00);
5497       br(NE, SET_RESULT);
5498       subs(len, len, 1);
5499       br(GT, NEXT_1);
5500 
5501     BIND(SET_RESULT);
5502       sub(result, result, len); // Return index where we stopped
5503                                 // Return len == 0 if we processed all
5504                                 // characters
5505     BIND(DONE);
5506 }
5507 
5508 
5509 // Inflate byte[] array to char[].
5510 void MacroAssembler::byte_array_inflate(Register src, Register dst, Register len,
5511                                         FloatRegister vtmp1, FloatRegister vtmp2, FloatRegister vtmp3,
5512                                         Register tmp4) {
5513   Label big, done;
5514 
5515   assert_different_registers(src, dst, len, tmp4, rscratch1);
5516 
5517   fmovd(vtmp1 , zr);
5518   lsrw(rscratch1, len, 3);
5519 
5520   cbnzw(rscratch1, big);
5521 
5522   // Short string: less than 8 bytes.
5523   {
5524     Label loop, around, tiny;
5525 
5526     subsw(len, len, 4);
5527     andw(len, len, 3);
5528     br(LO, tiny);
5529 
5530     // Use SIMD to do 4 bytes.
5531     ldrs(vtmp2, post(src, 4));
5532     zip1(vtmp3, T8B, vtmp2, vtmp1);
5533     strd(vtmp3, post(dst, 8));
5534 
5535     cbzw(len, done);
5536 
5537     // Do the remaining bytes by steam.
5538     bind(loop);
5539     ldrb(tmp4, post(src, 1));
5540     strh(tmp4, post(dst, 2));
5541     subw(len, len, 1);
5542 
5543     bind(tiny);
5544     cbnz(len, loop);
5545 
5546     bind(around);
5547     b(done);
5548   }
5549 
5550   // Unpack the bytes 8 at a time.
5551   bind(big);
5552   andw(len, len, 7);
5553 
5554   {
5555     Label loop, around;
5556 
5557     bind(loop);
5558     ldrd(vtmp2, post(src, 8));
5559     sub(rscratch1, rscratch1, 1);
5560     zip1(vtmp3, T16B, vtmp2, vtmp1);
5561     st1(vtmp3, T8H, post(dst, 16));
5562     cbnz(rscratch1, loop);
5563 
5564     bind(around);
5565   }
5566 
5567   // Do the tail of up to 8 bytes.
5568   sub(src, src, 8);
5569   add(src, src, len, ext::uxtw, 0);
5570   ldrd(vtmp2, Address(src));
5571   sub(dst, dst, 16);
5572   add(dst, dst, len, ext::uxtw, 1);
5573   zip1(vtmp3, T16B, vtmp2, vtmp1);
5574   st1(vtmp3, T8H, Address(dst));
5575 
5576   bind(done);
5577 }
5578 
5579 // Compress char[] array to byte[].
5580 void MacroAssembler::char_array_compress(Register src, Register dst, Register len,
5581                                          FloatRegister tmp1Reg, FloatRegister tmp2Reg,
5582                                          FloatRegister tmp3Reg, FloatRegister tmp4Reg,
5583                                          Register result) {
5584   encode_iso_array(src, dst, len, result,
5585                    tmp1Reg, tmp2Reg, tmp3Reg, tmp4Reg);
5586   cmp(len, zr);
5587   csel(result, result, zr, EQ);
5588 }
5589 
5590 // get_thread() can be called anywhere inside generated code so we
5591 // need to save whatever non-callee save context might get clobbered
5592 // by the call to JavaThread::aarch64_get_thread_helper() or, indeed,
5593 // the call setup code.
5594 //
5595 // aarch64_get_thread_helper() clobbers only r0, r1, and flags.
5596 //
5597 void MacroAssembler::get_thread(Register dst) {
5598   RegSet saved_regs = RegSet::range(r0, r1) + lr - dst;
5599   push(saved_regs, sp);
5600 
5601   mov(lr, CAST_FROM_FN_PTR(address, JavaThread::aarch64_get_thread_helper));
5602   blrt(lr, 1, 0, 1);
5603   if (dst != c_rarg0) {
5604     mov(dst, c_rarg0);
5605   }
5606 
5607   pop(saved_regs, sp);
5608 }