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      1 /*
      2  * Copyright (C) 2014 The Android Open Source Project
      3  *
      4  * Licensed under the Apache License, Version 2.0 (the "License");
      5  * you may not use this file except in compliance with the License.
      6  * You may obtain a copy of the License at
      7  *
      8  *      http://www.apache.org/licenses/LICENSE-2.0
      9  *
     10  * Unless required by applicable law or agreed to in writing, software
     11  * distributed under the License is distributed on an "AS IS" BASIS,
     12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     13  * See the License for the specific language governing permissions and
     14  * limitations under the License.
     15  */
     16 
     17 #ifndef ART_COMPILER_UTILS_MIPS64_ASSEMBLER_MIPS64_H_
     18 #define ART_COMPILER_UTILS_MIPS64_ASSEMBLER_MIPS64_H_
     19 
     20 #include <deque>
     21 #include <utility>
     22 #include <vector>
     23 
     24 #include "arch/mips64/instruction_set_features_mips64.h"
     25 #include "base/arena_containers.h"
     26 #include "base/enums.h"
     27 #include "base/macros.h"
     28 #include "base/stl_util_identity.h"
     29 #include "constants_mips64.h"
     30 #include "globals.h"
     31 #include "managed_register_mips64.h"
     32 #include "offsets.h"
     33 #include "utils/assembler.h"
     34 #include "utils/jni_macro_assembler.h"
     35 #include "utils/label.h"
     36 
     37 namespace art {
     38 namespace mips64 {
     39 
     40 enum LoadConst64Path {
     41   kLoadConst64PathZero           = 0x0,
     42   kLoadConst64PathOri            = 0x1,
     43   kLoadConst64PathDaddiu         = 0x2,
     44   kLoadConst64PathLui            = 0x4,
     45   kLoadConst64PathLuiOri         = 0x8,
     46   kLoadConst64PathOriDahi        = 0x10,
     47   kLoadConst64PathOriDati        = 0x20,
     48   kLoadConst64PathLuiDahi        = 0x40,
     49   kLoadConst64PathLuiDati        = 0x80,
     50   kLoadConst64PathDaddiuDsrlX    = 0x100,
     51   kLoadConst64PathOriDsllX       = 0x200,
     52   kLoadConst64PathDaddiuDsllX    = 0x400,
     53   kLoadConst64PathLuiOriDsllX    = 0x800,
     54   kLoadConst64PathOriDsllXOri    = 0x1000,
     55   kLoadConst64PathDaddiuDsllXOri = 0x2000,
     56   kLoadConst64PathDaddiuDahi     = 0x4000,
     57   kLoadConst64PathDaddiuDati     = 0x8000,
     58   kLoadConst64PathDinsu1         = 0x10000,
     59   kLoadConst64PathDinsu2         = 0x20000,
     60   kLoadConst64PathCatchAll       = 0x40000,
     61   kLoadConst64PathAllPaths       = 0x7ffff,
     62 };
     63 
     64 template <typename Asm>
     65 void TemplateLoadConst32(Asm* a, GpuRegister rd, int32_t value) {
     66   if (IsUint<16>(value)) {
     67     // Use OR with (unsigned) immediate to encode 16b unsigned int.
     68     a->Ori(rd, ZERO, value);
     69   } else if (IsInt<16>(value)) {
     70     // Use ADD with (signed) immediate to encode 16b signed int.
     71     a->Addiu(rd, ZERO, value);
     72   } else {
     73     // Set 16 most significant bits of value. The "lui" instruction
     74     // also clears the 16 least significant bits to zero.
     75     a->Lui(rd, value >> 16);
     76     if (value & 0xFFFF) {
     77       // If the 16 least significant bits are non-zero, set them
     78       // here.
     79       a->Ori(rd, rd, value);
     80     }
     81   }
     82 }
     83 
     84 static inline int InstrCountForLoadReplicatedConst32(int64_t value) {
     85   int32_t x = Low32Bits(value);
     86   int32_t y = High32Bits(value);
     87 
     88   if (x == y) {
     89     return (IsUint<16>(x) || IsInt<16>(x) || ((x & 0xFFFF) == 0 && IsInt<16>(value >> 16))) ? 2 : 3;
     90   }
     91 
     92   return INT_MAX;
     93 }
     94 
     95 template <typename Asm, typename Rtype, typename Vtype>
     96 void TemplateLoadConst64(Asm* a, Rtype rd, Vtype value) {
     97   int bit31 = (value & UINT64_C(0x80000000)) != 0;
     98   int rep32_count = InstrCountForLoadReplicatedConst32(value);
     99 
    100   // Loads with 1 instruction.
    101   if (IsUint<16>(value)) {
    102     // 64-bit value can be loaded as an unsigned 16-bit number.
    103     a->RecordLoadConst64Path(kLoadConst64PathOri);
    104     a->Ori(rd, ZERO, value);
    105   } else if (IsInt<16>(value)) {
    106     // 64-bit value can be loaded as an signed 16-bit number.
    107     a->RecordLoadConst64Path(kLoadConst64PathDaddiu);
    108     a->Daddiu(rd, ZERO, value);
    109   } else if ((value & 0xFFFF) == 0 && IsInt<16>(value >> 16)) {
    110     // 64-bit value can be loaded as an signed 32-bit number which has all
    111     // of its 16 least significant bits set to zero.
    112     a->RecordLoadConst64Path(kLoadConst64PathLui);
    113     a->Lui(rd, value >> 16);
    114   } else if (IsInt<32>(value)) {
    115     // Loads with 2 instructions.
    116     // 64-bit value can be loaded as an signed 32-bit number which has some
    117     // or all of its 16 least significant bits set to one.
    118     a->RecordLoadConst64Path(kLoadConst64PathLuiOri);
    119     a->Lui(rd, value >> 16);
    120     a->Ori(rd, rd, value);
    121   } else if ((value & 0xFFFF0000) == 0 && IsInt<16>(value >> 32)) {
    122     // 64-bit value which consists of an unsigned 16-bit value in its
    123     // least significant 32-bits, and a signed 16-bit value in its
    124     // most significant 32-bits.
    125     a->RecordLoadConst64Path(kLoadConst64PathOriDahi);
    126     a->Ori(rd, ZERO, value);
    127     a->Dahi(rd, value >> 32);
    128   } else if ((value & UINT64_C(0xFFFFFFFF0000)) == 0) {
    129     // 64-bit value which consists of an unsigned 16-bit value in its
    130     // least significant 48-bits, and a signed 16-bit value in its
    131     // most significant 16-bits.
    132     a->RecordLoadConst64Path(kLoadConst64PathOriDati);
    133     a->Ori(rd, ZERO, value);
    134     a->Dati(rd, value >> 48);
    135   } else if ((value & 0xFFFF) == 0 &&
    136              (-32768 - bit31) <= (value >> 32) && (value >> 32) <= (32767 - bit31)) {
    137     // 16 LSBs (Least Significant Bits) all set to zero.
    138     // 48 MSBs (Most Significant Bits) hold a signed 32-bit value.
    139     a->RecordLoadConst64Path(kLoadConst64PathLuiDahi);
    140     a->Lui(rd, value >> 16);
    141     a->Dahi(rd, (value >> 32) + bit31);
    142   } else if ((value & 0xFFFF) == 0 && ((value >> 31) & 0x1FFFF) == ((0x20000 - bit31) & 0x1FFFF)) {
    143     // 16 LSBs all set to zero.
    144     // 48 MSBs hold a signed value which can't be represented by signed
    145     // 32-bit number, and the middle 16 bits are all zero, or all one.
    146     a->RecordLoadConst64Path(kLoadConst64PathLuiDati);
    147     a->Lui(rd, value >> 16);
    148     a->Dati(rd, (value >> 48) + bit31);
    149   } else if (IsInt<16>(static_cast<int32_t>(value)) &&
    150              (-32768 - bit31) <= (value >> 32) && (value >> 32) <= (32767 - bit31)) {
    151     // 32 LSBs contain an unsigned 16-bit number.
    152     // 32 MSBs contain a signed 16-bit number.
    153     a->RecordLoadConst64Path(kLoadConst64PathDaddiuDahi);
    154     a->Daddiu(rd, ZERO, value);
    155     a->Dahi(rd, (value >> 32) + bit31);
    156   } else if (IsInt<16>(static_cast<int32_t>(value)) &&
    157              ((value >> 31) & 0x1FFFF) == ((0x20000 - bit31) & 0x1FFFF)) {
    158     // 48 LSBs contain an unsigned 16-bit number.
    159     // 16 MSBs contain a signed 16-bit number.
    160     a->RecordLoadConst64Path(kLoadConst64PathDaddiuDati);
    161     a->Daddiu(rd, ZERO, value);
    162     a->Dati(rd, (value >> 48) + bit31);
    163   } else if (IsPowerOfTwo(value + UINT64_C(1))) {
    164     // 64-bit values which have their "n" MSBs set to one, and their
    165     // "64-n" LSBs set to zero. "n" must meet the restrictions 0 < n < 64.
    166     int shift_cnt = 64 - CTZ(value + UINT64_C(1));
    167     a->RecordLoadConst64Path(kLoadConst64PathDaddiuDsrlX);
    168     a->Daddiu(rd, ZERO, -1);
    169     if (shift_cnt < 32) {
    170       a->Dsrl(rd, rd, shift_cnt);
    171     } else {
    172       a->Dsrl32(rd, rd, shift_cnt & 31);
    173     }
    174   } else {
    175     int shift_cnt = CTZ(value);
    176     int64_t tmp = value >> shift_cnt;
    177     a->RecordLoadConst64Path(kLoadConst64PathOriDsllX);
    178     if (IsUint<16>(tmp)) {
    179       // Value can be computed by loading a 16-bit unsigned value, and
    180       // then shifting left.
    181       a->Ori(rd, ZERO, tmp);
    182       if (shift_cnt < 32) {
    183         a->Dsll(rd, rd, shift_cnt);
    184       } else {
    185         a->Dsll32(rd, rd, shift_cnt & 31);
    186       }
    187     } else if (IsInt<16>(tmp)) {
    188       // Value can be computed by loading a 16-bit signed value, and
    189       // then shifting left.
    190       a->RecordLoadConst64Path(kLoadConst64PathDaddiuDsllX);
    191       a->Daddiu(rd, ZERO, tmp);
    192       if (shift_cnt < 32) {
    193         a->Dsll(rd, rd, shift_cnt);
    194       } else {
    195         a->Dsll32(rd, rd, shift_cnt & 31);
    196       }
    197     } else if (rep32_count < 3) {
    198       // Value being loaded has 32 LSBs equal to the 32 MSBs, and the
    199       // value loaded into the 32 LSBs can be loaded with a single
    200       // MIPS instruction.
    201       a->LoadConst32(rd, value);
    202       a->Dinsu(rd, rd, 32, 32);
    203       a->RecordLoadConst64Path(kLoadConst64PathDinsu1);
    204     } else if (IsInt<32>(tmp)) {
    205       // Loads with 3 instructions.
    206       // Value can be computed by loading a 32-bit signed value, and
    207       // then shifting left.
    208       a->RecordLoadConst64Path(kLoadConst64PathLuiOriDsllX);
    209       a->Lui(rd, tmp >> 16);
    210       a->Ori(rd, rd, tmp);
    211       if (shift_cnt < 32) {
    212         a->Dsll(rd, rd, shift_cnt);
    213       } else {
    214         a->Dsll32(rd, rd, shift_cnt & 31);
    215       }
    216     } else {
    217       shift_cnt = 16 + CTZ(value >> 16);
    218       tmp = value >> shift_cnt;
    219       if (IsUint<16>(tmp)) {
    220         // Value can be computed by loading a 16-bit unsigned value,
    221         // shifting left, and "or"ing in another 16-bit unsigned value.
    222         a->RecordLoadConst64Path(kLoadConst64PathOriDsllXOri);
    223         a->Ori(rd, ZERO, tmp);
    224         if (shift_cnt < 32) {
    225           a->Dsll(rd, rd, shift_cnt);
    226         } else {
    227           a->Dsll32(rd, rd, shift_cnt & 31);
    228         }
    229         a->Ori(rd, rd, value);
    230       } else if (IsInt<16>(tmp)) {
    231         // Value can be computed by loading a 16-bit signed value,
    232         // shifting left, and "or"ing in a 16-bit unsigned value.
    233         a->RecordLoadConst64Path(kLoadConst64PathDaddiuDsllXOri);
    234         a->Daddiu(rd, ZERO, tmp);
    235         if (shift_cnt < 32) {
    236           a->Dsll(rd, rd, shift_cnt);
    237         } else {
    238           a->Dsll32(rd, rd, shift_cnt & 31);
    239         }
    240         a->Ori(rd, rd, value);
    241       } else if (rep32_count < 4) {
    242         // Value being loaded has 32 LSBs equal to the 32 MSBs, and the
    243         // value in the 32 LSBs requires 2 MIPS instructions to load.
    244         a->LoadConst32(rd, value);
    245         a->Dinsu(rd, rd, 32, 32);
    246         a->RecordLoadConst64Path(kLoadConst64PathDinsu2);
    247       } else {
    248         // Loads with 3-4 instructions.
    249         // Catch-all case to get any other 64-bit values which aren't
    250         // handled by special cases above.
    251         uint64_t tmp2 = value;
    252         a->RecordLoadConst64Path(kLoadConst64PathCatchAll);
    253         a->LoadConst32(rd, value);
    254         if (bit31) {
    255           tmp2 += UINT64_C(0x100000000);
    256         }
    257         if (((tmp2 >> 32) & 0xFFFF) != 0) {
    258           a->Dahi(rd, tmp2 >> 32);
    259         }
    260         if (tmp2 & UINT64_C(0x800000000000)) {
    261           tmp2 += UINT64_C(0x1000000000000);
    262         }
    263         if ((tmp2 >> 48) != 0) {
    264           a->Dati(rd, tmp2 >> 48);
    265         }
    266       }
    267     }
    268   }
    269 }
    270 
    271 static constexpr size_t kMips64HalfwordSize = 2;
    272 static constexpr size_t kMips64WordSize = 4;
    273 static constexpr size_t kMips64DoublewordSize = 8;
    274 
    275 enum LoadOperandType {
    276   kLoadSignedByte,
    277   kLoadUnsignedByte,
    278   kLoadSignedHalfword,
    279   kLoadUnsignedHalfword,
    280   kLoadWord,
    281   kLoadUnsignedWord,
    282   kLoadDoubleword,
    283   kLoadQuadword
    284 };
    285 
    286 enum StoreOperandType {
    287   kStoreByte,
    288   kStoreHalfword,
    289   kStoreWord,
    290   kStoreDoubleword,
    291   kStoreQuadword
    292 };
    293 
    294 // Used to test the values returned by ClassS/ClassD.
    295 enum FPClassMaskType {
    296   kSignalingNaN      = 0x001,
    297   kQuietNaN          = 0x002,
    298   kNegativeInfinity  = 0x004,
    299   kNegativeNormal    = 0x008,
    300   kNegativeSubnormal = 0x010,
    301   kNegativeZero      = 0x020,
    302   kPositiveInfinity  = 0x040,
    303   kPositiveNormal    = 0x080,
    304   kPositiveSubnormal = 0x100,
    305   kPositiveZero      = 0x200,
    306 };
    307 
    308 class Mips64Label : public Label {
    309  public:
    310   Mips64Label() : prev_branch_id_plus_one_(0) {}
    311 
    312   Mips64Label(Mips64Label&& src)
    313       : Label(std::move(src)), prev_branch_id_plus_one_(src.prev_branch_id_plus_one_) {}
    314 
    315  private:
    316   uint32_t prev_branch_id_plus_one_;  // To get distance from preceding branch, if any.
    317 
    318   friend class Mips64Assembler;
    319   DISALLOW_COPY_AND_ASSIGN(Mips64Label);
    320 };
    321 
    322 // Assembler literal is a value embedded in code, retrieved using a PC-relative load.
    323 class Literal {
    324  public:
    325   static constexpr size_t kMaxSize = 8;
    326 
    327   Literal(uint32_t size, const uint8_t* data)
    328       : label_(), size_(size) {
    329     DCHECK_LE(size, Literal::kMaxSize);
    330     memcpy(data_, data, size);
    331   }
    332 
    333   template <typename T>
    334   T GetValue() const {
    335     DCHECK_EQ(size_, sizeof(T));
    336     T value;
    337     memcpy(&value, data_, sizeof(T));
    338     return value;
    339   }
    340 
    341   uint32_t GetSize() const {
    342     return size_;
    343   }
    344 
    345   const uint8_t* GetData() const {
    346     return data_;
    347   }
    348 
    349   Mips64Label* GetLabel() {
    350     return &label_;
    351   }
    352 
    353   const Mips64Label* GetLabel() const {
    354     return &label_;
    355   }
    356 
    357  private:
    358   Mips64Label label_;
    359   const uint32_t size_;
    360   uint8_t data_[kMaxSize];
    361 
    362   DISALLOW_COPY_AND_ASSIGN(Literal);
    363 };
    364 
    365 // Jump table: table of labels emitted after the code and before the literals. Similar to literals.
    366 class JumpTable {
    367  public:
    368   explicit JumpTable(std::vector<Mips64Label*>&& labels)
    369       : label_(), labels_(std::move(labels)) {
    370   }
    371 
    372   size_t GetSize() const {
    373     return labels_.size() * sizeof(uint32_t);
    374   }
    375 
    376   const std::vector<Mips64Label*>& GetData() const {
    377     return labels_;
    378   }
    379 
    380   Mips64Label* GetLabel() {
    381     return &label_;
    382   }
    383 
    384   const Mips64Label* GetLabel() const {
    385     return &label_;
    386   }
    387 
    388  private:
    389   Mips64Label label_;
    390   std::vector<Mips64Label*> labels_;
    391 
    392   DISALLOW_COPY_AND_ASSIGN(JumpTable);
    393 };
    394 
    395 // Slowpath entered when Thread::Current()->_exception is non-null.
    396 class Mips64ExceptionSlowPath {
    397  public:
    398   explicit Mips64ExceptionSlowPath(Mips64ManagedRegister scratch, size_t stack_adjust)
    399       : scratch_(scratch), stack_adjust_(stack_adjust) {}
    400 
    401   Mips64ExceptionSlowPath(Mips64ExceptionSlowPath&& src)
    402       : scratch_(src.scratch_),
    403         stack_adjust_(src.stack_adjust_),
    404         exception_entry_(std::move(src.exception_entry_)) {}
    405 
    406  private:
    407   Mips64Label* Entry() { return &exception_entry_; }
    408   const Mips64ManagedRegister scratch_;
    409   const size_t stack_adjust_;
    410   Mips64Label exception_entry_;
    411 
    412   friend class Mips64Assembler;
    413   DISALLOW_COPY_AND_ASSIGN(Mips64ExceptionSlowPath);
    414 };
    415 
    416 class Mips64Assembler FINAL : public Assembler, public JNIMacroAssembler<PointerSize::k64> {
    417  public:
    418   using JNIBase = JNIMacroAssembler<PointerSize::k64>;
    419 
    420   explicit Mips64Assembler(ArenaAllocator* arena,
    421                            const Mips64InstructionSetFeatures* instruction_set_features = nullptr)
    422       : Assembler(arena),
    423         overwriting_(false),
    424         overwrite_location_(0),
    425         literals_(arena->Adapter(kArenaAllocAssembler)),
    426         long_literals_(arena->Adapter(kArenaAllocAssembler)),
    427         jump_tables_(arena->Adapter(kArenaAllocAssembler)),
    428         last_position_adjustment_(0),
    429         last_old_position_(0),
    430         last_branch_id_(0),
    431         has_msa_(instruction_set_features != nullptr ? instruction_set_features->HasMsa() : false) {
    432     cfi().DelayEmittingAdvancePCs();
    433   }
    434 
    435   virtual ~Mips64Assembler() {
    436     for (auto& branch : branches_) {
    437       CHECK(branch.IsResolved());
    438     }
    439   }
    440 
    441   size_t CodeSize() const OVERRIDE { return Assembler::CodeSize(); }
    442   DebugFrameOpCodeWriterForAssembler& cfi() { return Assembler::cfi(); }
    443 
    444   // Emit Machine Instructions.
    445   void Addu(GpuRegister rd, GpuRegister rs, GpuRegister rt);
    446   void Addiu(GpuRegister rt, GpuRegister rs, uint16_t imm16);
    447   void Daddu(GpuRegister rd, GpuRegister rs, GpuRegister rt);  // MIPS64
    448   void Daddiu(GpuRegister rt, GpuRegister rs, uint16_t imm16);  // MIPS64
    449   void Subu(GpuRegister rd, GpuRegister rs, GpuRegister rt);
    450   void Dsubu(GpuRegister rd, GpuRegister rs, GpuRegister rt);  // MIPS64
    451 
    452   void MulR6(GpuRegister rd, GpuRegister rs, GpuRegister rt);
    453   void MuhR6(GpuRegister rd, GpuRegister rs, GpuRegister rt);
    454   void DivR6(GpuRegister rd, GpuRegister rs, GpuRegister rt);
    455   void ModR6(GpuRegister rd, GpuRegister rs, GpuRegister rt);
    456   void DivuR6(GpuRegister rd, GpuRegister rs, GpuRegister rt);
    457   void ModuR6(GpuRegister rd, GpuRegister rs, GpuRegister rt);
    458   void Dmul(GpuRegister rd, GpuRegister rs, GpuRegister rt);  // MIPS64
    459   void Dmuh(GpuRegister rd, GpuRegister rs, GpuRegister rt);  // MIPS64
    460   void Ddiv(GpuRegister rd, GpuRegister rs, GpuRegister rt);  // MIPS64
    461   void Dmod(GpuRegister rd, GpuRegister rs, GpuRegister rt);  // MIPS64
    462   void Ddivu(GpuRegister rd, GpuRegister rs, GpuRegister rt);  // MIPS64
    463   void Dmodu(GpuRegister rd, GpuRegister rs, GpuRegister rt);  // MIPS64
    464 
    465   void And(GpuRegister rd, GpuRegister rs, GpuRegister rt);
    466   void Andi(GpuRegister rt, GpuRegister rs, uint16_t imm16);
    467   void Or(GpuRegister rd, GpuRegister rs, GpuRegister rt);
    468   void Ori(GpuRegister rt, GpuRegister rs, uint16_t imm16);
    469   void Xor(GpuRegister rd, GpuRegister rs, GpuRegister rt);
    470   void Xori(GpuRegister rt, GpuRegister rs, uint16_t imm16);
    471   void Nor(GpuRegister rd, GpuRegister rs, GpuRegister rt);
    472 
    473   void Bitswap(GpuRegister rd, GpuRegister rt);
    474   void Dbitswap(GpuRegister rd, GpuRegister rt);  // MIPS64
    475   void Seb(GpuRegister rd, GpuRegister rt);
    476   void Seh(GpuRegister rd, GpuRegister rt);
    477   void Dsbh(GpuRegister rd, GpuRegister rt);  // MIPS64
    478   void Dshd(GpuRegister rd, GpuRegister rt);  // MIPS64
    479   void Dext(GpuRegister rs, GpuRegister rt, int pos, int size);  // MIPS64
    480   void Dinsu(GpuRegister rt, GpuRegister rs, int pos, int size);  // MIPS64
    481   void Lsa(GpuRegister rd, GpuRegister rs, GpuRegister rt, int saPlusOne);
    482   void Dlsa(GpuRegister rd, GpuRegister rs, GpuRegister rt, int saPlusOne);  // MIPS64
    483   void Wsbh(GpuRegister rd, GpuRegister rt);
    484   void Sc(GpuRegister rt, GpuRegister base, int16_t imm9 = 0);
    485   void Scd(GpuRegister rt, GpuRegister base, int16_t imm9 = 0);  // MIPS64
    486   void Ll(GpuRegister rt, GpuRegister base, int16_t imm9 = 0);
    487   void Lld(GpuRegister rt, GpuRegister base, int16_t imm9 = 0);  // MIPS64
    488 
    489   void Sll(GpuRegister rd, GpuRegister rt, int shamt);
    490   void Srl(GpuRegister rd, GpuRegister rt, int shamt);
    491   void Rotr(GpuRegister rd, GpuRegister rt, int shamt);
    492   void Sra(GpuRegister rd, GpuRegister rt, int shamt);
    493   void Sllv(GpuRegister rd, GpuRegister rt, GpuRegister rs);
    494   void Srlv(GpuRegister rd, GpuRegister rt, GpuRegister rs);
    495   void Rotrv(GpuRegister rd, GpuRegister rt, GpuRegister rs);
    496   void Srav(GpuRegister rd, GpuRegister rt, GpuRegister rs);
    497   void Dsll(GpuRegister rd, GpuRegister rt, int shamt);  // MIPS64
    498   void Dsrl(GpuRegister rd, GpuRegister rt, int shamt);  // MIPS64
    499   void Drotr(GpuRegister rd, GpuRegister rt, int shamt);  // MIPS64
    500   void Dsra(GpuRegister rd, GpuRegister rt, int shamt);  // MIPS64
    501   void Dsll32(GpuRegister rd, GpuRegister rt, int shamt);  // MIPS64
    502   void Dsrl32(GpuRegister rd, GpuRegister rt, int shamt);  // MIPS64
    503   void Drotr32(GpuRegister rd, GpuRegister rt, int shamt);  // MIPS64
    504   void Dsra32(GpuRegister rd, GpuRegister rt, int shamt);  // MIPS64
    505   void Dsllv(GpuRegister rd, GpuRegister rt, GpuRegister rs);  // MIPS64
    506   void Dsrlv(GpuRegister rd, GpuRegister rt, GpuRegister rs);  // MIPS64
    507   void Drotrv(GpuRegister rd, GpuRegister rt, GpuRegister rs);  // MIPS64
    508   void Dsrav(GpuRegister rd, GpuRegister rt, GpuRegister rs);  // MIPS64
    509 
    510   void Lb(GpuRegister rt, GpuRegister rs, uint16_t imm16);
    511   void Lh(GpuRegister rt, GpuRegister rs, uint16_t imm16);
    512   void Lw(GpuRegister rt, GpuRegister rs, uint16_t imm16);
    513   void Ld(GpuRegister rt, GpuRegister rs, uint16_t imm16);  // MIPS64
    514   void Lbu(GpuRegister rt, GpuRegister rs, uint16_t imm16);
    515   void Lhu(GpuRegister rt, GpuRegister rs, uint16_t imm16);
    516   void Lwu(GpuRegister rt, GpuRegister rs, uint16_t imm16);  // MIPS64
    517   void Lwpc(GpuRegister rs, uint32_t imm19);
    518   void Lwupc(GpuRegister rs, uint32_t imm19);  // MIPS64
    519   void Ldpc(GpuRegister rs, uint32_t imm18);  // MIPS64
    520   void Lui(GpuRegister rt, uint16_t imm16);
    521   void Aui(GpuRegister rt, GpuRegister rs, uint16_t imm16);
    522   void Daui(GpuRegister rt, GpuRegister rs, uint16_t imm16);  // MIPS64
    523   void Dahi(GpuRegister rs, uint16_t imm16);  // MIPS64
    524   void Dati(GpuRegister rs, uint16_t imm16);  // MIPS64
    525   void Sync(uint32_t stype);
    526 
    527   void Sb(GpuRegister rt, GpuRegister rs, uint16_t imm16);
    528   void Sh(GpuRegister rt, GpuRegister rs, uint16_t imm16);
    529   void Sw(GpuRegister rt, GpuRegister rs, uint16_t imm16);
    530   void Sd(GpuRegister rt, GpuRegister rs, uint16_t imm16);  // MIPS64
    531 
    532   void Slt(GpuRegister rd, GpuRegister rs, GpuRegister rt);
    533   void Sltu(GpuRegister rd, GpuRegister rs, GpuRegister rt);
    534   void Slti(GpuRegister rt, GpuRegister rs, uint16_t imm16);
    535   void Sltiu(GpuRegister rt, GpuRegister rs, uint16_t imm16);
    536   void Seleqz(GpuRegister rd, GpuRegister rs, GpuRegister rt);
    537   void Selnez(GpuRegister rd, GpuRegister rs, GpuRegister rt);
    538   void Clz(GpuRegister rd, GpuRegister rs);
    539   void Clo(GpuRegister rd, GpuRegister rs);
    540   void Dclz(GpuRegister rd, GpuRegister rs);  // MIPS64
    541   void Dclo(GpuRegister rd, GpuRegister rs);  // MIPS64
    542 
    543   void Jalr(GpuRegister rd, GpuRegister rs);
    544   void Jalr(GpuRegister rs);
    545   void Jr(GpuRegister rs);
    546   void Auipc(GpuRegister rs, uint16_t imm16);
    547   void Addiupc(GpuRegister rs, uint32_t imm19);
    548   void Bc(uint32_t imm26);
    549   void Balc(uint32_t imm26);
    550   void Jic(GpuRegister rt, uint16_t imm16);
    551   void Jialc(GpuRegister rt, uint16_t imm16);
    552   void Bltc(GpuRegister rs, GpuRegister rt, uint16_t imm16);
    553   void Bltzc(GpuRegister rt, uint16_t imm16);
    554   void Bgtzc(GpuRegister rt, uint16_t imm16);
    555   void Bgec(GpuRegister rs, GpuRegister rt, uint16_t imm16);
    556   void Bgezc(GpuRegister rt, uint16_t imm16);
    557   void Blezc(GpuRegister rt, uint16_t imm16);
    558   void Bltuc(GpuRegister rs, GpuRegister rt, uint16_t imm16);
    559   void Bgeuc(GpuRegister rs, GpuRegister rt, uint16_t imm16);
    560   void Beqc(GpuRegister rs, GpuRegister rt, uint16_t imm16);
    561   void Bnec(GpuRegister rs, GpuRegister rt, uint16_t imm16);
    562   void Beqzc(GpuRegister rs, uint32_t imm21);
    563   void Bnezc(GpuRegister rs, uint32_t imm21);
    564   void Bc1eqz(FpuRegister ft, uint16_t imm16);
    565   void Bc1nez(FpuRegister ft, uint16_t imm16);
    566 
    567   void AddS(FpuRegister fd, FpuRegister fs, FpuRegister ft);
    568   void SubS(FpuRegister fd, FpuRegister fs, FpuRegister ft);
    569   void MulS(FpuRegister fd, FpuRegister fs, FpuRegister ft);
    570   void DivS(FpuRegister fd, FpuRegister fs, FpuRegister ft);
    571   void AddD(FpuRegister fd, FpuRegister fs, FpuRegister ft);
    572   void SubD(FpuRegister fd, FpuRegister fs, FpuRegister ft);
    573   void MulD(FpuRegister fd, FpuRegister fs, FpuRegister ft);
    574   void DivD(FpuRegister fd, FpuRegister fs, FpuRegister ft);
    575   void SqrtS(FpuRegister fd, FpuRegister fs);
    576   void SqrtD(FpuRegister fd, FpuRegister fs);
    577   void AbsS(FpuRegister fd, FpuRegister fs);
    578   void AbsD(FpuRegister fd, FpuRegister fs);
    579   void MovS(FpuRegister fd, FpuRegister fs);
    580   void MovD(FpuRegister fd, FpuRegister fs);
    581   void NegS(FpuRegister fd, FpuRegister fs);
    582   void NegD(FpuRegister fd, FpuRegister fs);
    583   void RoundLS(FpuRegister fd, FpuRegister fs);
    584   void RoundLD(FpuRegister fd, FpuRegister fs);
    585   void RoundWS(FpuRegister fd, FpuRegister fs);
    586   void RoundWD(FpuRegister fd, FpuRegister fs);
    587   void TruncLS(FpuRegister fd, FpuRegister fs);
    588   void TruncLD(FpuRegister fd, FpuRegister fs);
    589   void TruncWS(FpuRegister fd, FpuRegister fs);
    590   void TruncWD(FpuRegister fd, FpuRegister fs);
    591   void CeilLS(FpuRegister fd, FpuRegister fs);
    592   void CeilLD(FpuRegister fd, FpuRegister fs);
    593   void CeilWS(FpuRegister fd, FpuRegister fs);
    594   void CeilWD(FpuRegister fd, FpuRegister fs);
    595   void FloorLS(FpuRegister fd, FpuRegister fs);
    596   void FloorLD(FpuRegister fd, FpuRegister fs);
    597   void FloorWS(FpuRegister fd, FpuRegister fs);
    598   void FloorWD(FpuRegister fd, FpuRegister fs);
    599   void SelS(FpuRegister fd, FpuRegister fs, FpuRegister ft);
    600   void SelD(FpuRegister fd, FpuRegister fs, FpuRegister ft);
    601   void RintS(FpuRegister fd, FpuRegister fs);
    602   void RintD(FpuRegister fd, FpuRegister fs);
    603   void ClassS(FpuRegister fd, FpuRegister fs);
    604   void ClassD(FpuRegister fd, FpuRegister fs);
    605   void MinS(FpuRegister fd, FpuRegister fs, FpuRegister ft);
    606   void MinD(FpuRegister fd, FpuRegister fs, FpuRegister ft);
    607   void MaxS(FpuRegister fd, FpuRegister fs, FpuRegister ft);
    608   void MaxD(FpuRegister fd, FpuRegister fs, FpuRegister ft);
    609   void CmpUnS(FpuRegister fd, FpuRegister fs, FpuRegister ft);
    610   void CmpEqS(FpuRegister fd, FpuRegister fs, FpuRegister ft);
    611   void CmpUeqS(FpuRegister fd, FpuRegister fs, FpuRegister ft);
    612   void CmpLtS(FpuRegister fd, FpuRegister fs, FpuRegister ft);
    613   void CmpUltS(FpuRegister fd, FpuRegister fs, FpuRegister ft);
    614   void CmpLeS(FpuRegister fd, FpuRegister fs, FpuRegister ft);
    615   void CmpUleS(FpuRegister fd, FpuRegister fs, FpuRegister ft);
    616   void CmpOrS(FpuRegister fd, FpuRegister fs, FpuRegister ft);
    617   void CmpUneS(FpuRegister fd, FpuRegister fs, FpuRegister ft);
    618   void CmpNeS(FpuRegister fd, FpuRegister fs, FpuRegister ft);
    619   void CmpUnD(FpuRegister fd, FpuRegister fs, FpuRegister ft);
    620   void CmpEqD(FpuRegister fd, FpuRegister fs, FpuRegister ft);
    621   void CmpUeqD(FpuRegister fd, FpuRegister fs, FpuRegister ft);
    622   void CmpLtD(FpuRegister fd, FpuRegister fs, FpuRegister ft);
    623   void CmpUltD(FpuRegister fd, FpuRegister fs, FpuRegister ft);
    624   void CmpLeD(FpuRegister fd, FpuRegister fs, FpuRegister ft);
    625   void CmpUleD(FpuRegister fd, FpuRegister fs, FpuRegister ft);
    626   void CmpOrD(FpuRegister fd, FpuRegister fs, FpuRegister ft);
    627   void CmpUneD(FpuRegister fd, FpuRegister fs, FpuRegister ft);
    628   void CmpNeD(FpuRegister fd, FpuRegister fs, FpuRegister ft);
    629 
    630   void Cvtsw(FpuRegister fd, FpuRegister fs);
    631   void Cvtdw(FpuRegister fd, FpuRegister fs);
    632   void Cvtsd(FpuRegister fd, FpuRegister fs);
    633   void Cvtds(FpuRegister fd, FpuRegister fs);
    634   void Cvtsl(FpuRegister fd, FpuRegister fs);
    635   void Cvtdl(FpuRegister fd, FpuRegister fs);
    636 
    637   void Mfc1(GpuRegister rt, FpuRegister fs);
    638   void Mfhc1(GpuRegister rt, FpuRegister fs);
    639   void Mtc1(GpuRegister rt, FpuRegister fs);
    640   void Mthc1(GpuRegister rt, FpuRegister fs);
    641   void Dmfc1(GpuRegister rt, FpuRegister fs);  // MIPS64
    642   void Dmtc1(GpuRegister rt, FpuRegister fs);  // MIPS64
    643   void Lwc1(FpuRegister ft, GpuRegister rs, uint16_t imm16);
    644   void Ldc1(FpuRegister ft, GpuRegister rs, uint16_t imm16);
    645   void Swc1(FpuRegister ft, GpuRegister rs, uint16_t imm16);
    646   void Sdc1(FpuRegister ft, GpuRegister rs, uint16_t imm16);
    647 
    648   void Break();
    649   void Nop();
    650   void Move(GpuRegister rd, GpuRegister rs);
    651   void Clear(GpuRegister rd);
    652   void Not(GpuRegister rd, GpuRegister rs);
    653 
    654   // MSA instructions.
    655   void AndV(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    656   void OrV(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    657   void NorV(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    658   void XorV(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    659 
    660   void AddvB(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    661   void AddvH(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    662   void AddvW(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    663   void AddvD(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    664   void SubvB(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    665   void SubvH(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    666   void SubvW(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    667   void SubvD(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    668   void MulvB(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    669   void MulvH(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    670   void MulvW(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    671   void MulvD(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    672   void Div_sB(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    673   void Div_sH(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    674   void Div_sW(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    675   void Div_sD(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    676   void Div_uB(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    677   void Div_uH(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    678   void Div_uW(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    679   void Div_uD(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    680   void Mod_sB(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    681   void Mod_sH(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    682   void Mod_sW(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    683   void Mod_sD(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    684   void Mod_uB(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    685   void Mod_uH(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    686   void Mod_uW(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    687   void Mod_uD(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    688   void Add_aB(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    689   void Add_aH(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    690   void Add_aW(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    691   void Add_aD(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    692   void Ave_sB(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    693   void Ave_sH(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    694   void Ave_sW(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    695   void Ave_sD(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    696   void Ave_uB(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    697   void Ave_uH(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    698   void Ave_uW(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    699   void Ave_uD(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    700   void Aver_sB(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    701   void Aver_sH(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    702   void Aver_sW(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    703   void Aver_sD(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    704   void Aver_uB(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    705   void Aver_uH(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    706   void Aver_uW(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    707   void Aver_uD(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    708   void Max_sB(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    709   void Max_sH(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    710   void Max_sW(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    711   void Max_sD(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    712   void Max_uB(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    713   void Max_uH(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    714   void Max_uW(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    715   void Max_uD(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    716   void Min_sB(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    717   void Min_sH(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    718   void Min_sW(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    719   void Min_sD(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    720   void Min_uB(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    721   void Min_uH(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    722   void Min_uW(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    723   void Min_uD(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    724 
    725   void FaddW(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    726   void FaddD(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    727   void FsubW(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    728   void FsubD(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    729   void FmulW(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    730   void FmulD(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    731   void FdivW(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    732   void FdivD(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    733   void FmaxW(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    734   void FmaxD(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    735   void FminW(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    736   void FminD(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    737 
    738   void Ffint_sW(VectorRegister wd, VectorRegister ws);
    739   void Ffint_sD(VectorRegister wd, VectorRegister ws);
    740   void Ftint_sW(VectorRegister wd, VectorRegister ws);
    741   void Ftint_sD(VectorRegister wd, VectorRegister ws);
    742 
    743   void SllB(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    744   void SllH(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    745   void SllW(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    746   void SllD(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    747   void SraB(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    748   void SraH(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    749   void SraW(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    750   void SraD(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    751   void SrlB(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    752   void SrlH(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    753   void SrlW(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    754   void SrlD(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    755 
    756   // Immediate shift instructions, where shamtN denotes shift amount (must be between 0 and 2^N-1).
    757   void SlliB(VectorRegister wd, VectorRegister ws, int shamt3);
    758   void SlliH(VectorRegister wd, VectorRegister ws, int shamt4);
    759   void SlliW(VectorRegister wd, VectorRegister ws, int shamt5);
    760   void SlliD(VectorRegister wd, VectorRegister ws, int shamt6);
    761   void SraiB(VectorRegister wd, VectorRegister ws, int shamt3);
    762   void SraiH(VectorRegister wd, VectorRegister ws, int shamt4);
    763   void SraiW(VectorRegister wd, VectorRegister ws, int shamt5);
    764   void SraiD(VectorRegister wd, VectorRegister ws, int shamt6);
    765   void SrliB(VectorRegister wd, VectorRegister ws, int shamt3);
    766   void SrliH(VectorRegister wd, VectorRegister ws, int shamt4);
    767   void SrliW(VectorRegister wd, VectorRegister ws, int shamt5);
    768   void SrliD(VectorRegister wd, VectorRegister ws, int shamt6);
    769 
    770   void MoveV(VectorRegister wd, VectorRegister ws);
    771   void SplatiB(VectorRegister wd, VectorRegister ws, int n4);
    772   void SplatiH(VectorRegister wd, VectorRegister ws, int n3);
    773   void SplatiW(VectorRegister wd, VectorRegister ws, int n2);
    774   void SplatiD(VectorRegister wd, VectorRegister ws, int n1);
    775   void FillB(VectorRegister wd, GpuRegister rs);
    776   void FillH(VectorRegister wd, GpuRegister rs);
    777   void FillW(VectorRegister wd, GpuRegister rs);
    778   void FillD(VectorRegister wd, GpuRegister rs);
    779 
    780   void LdiB(VectorRegister wd, int imm8);
    781   void LdiH(VectorRegister wd, int imm10);
    782   void LdiW(VectorRegister wd, int imm10);
    783   void LdiD(VectorRegister wd, int imm10);
    784   void LdB(VectorRegister wd, GpuRegister rs, int offset);
    785   void LdH(VectorRegister wd, GpuRegister rs, int offset);
    786   void LdW(VectorRegister wd, GpuRegister rs, int offset);
    787   void LdD(VectorRegister wd, GpuRegister rs, int offset);
    788   void StB(VectorRegister wd, GpuRegister rs, int offset);
    789   void StH(VectorRegister wd, GpuRegister rs, int offset);
    790   void StW(VectorRegister wd, GpuRegister rs, int offset);
    791   void StD(VectorRegister wd, GpuRegister rs, int offset);
    792 
    793   void IlvrB(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    794   void IlvrH(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    795   void IlvrW(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    796   void IlvrD(VectorRegister wd, VectorRegister ws, VectorRegister wt);
    797 
    798   // Helper for replicating floating point value in all destination elements.
    799   void ReplicateFPToVectorRegister(VectorRegister dst, FpuRegister src, bool is_double);
    800 
    801   // Higher level composite instructions.
    802   int InstrCountForLoadReplicatedConst32(int64_t);
    803   void LoadConst32(GpuRegister rd, int32_t value);
    804   void LoadConst64(GpuRegister rd, int64_t value);  // MIPS64
    805 
    806   // This function is only used for testing purposes.
    807   void RecordLoadConst64Path(int value);
    808 
    809   void Addiu32(GpuRegister rt, GpuRegister rs, int32_t value);
    810   void Daddiu64(GpuRegister rt, GpuRegister rs, int64_t value, GpuRegister rtmp = AT);  // MIPS64
    811 
    812   //
    813   // Heap poisoning.
    814   //
    815 
    816   // Poison a heap reference contained in `src` and store it in `dst`.
    817   void PoisonHeapReference(GpuRegister dst, GpuRegister src) {
    818     // dst = -src.
    819     // Negate the 32-bit ref.
    820     Dsubu(dst, ZERO, src);
    821     // And constrain it to 32 bits (zero-extend into bits 32 through 63) as on Arm64 and x86/64.
    822     Dext(dst, dst, 0, 32);
    823   }
    824   // Poison a heap reference contained in `reg`.
    825   void PoisonHeapReference(GpuRegister reg) {
    826     // reg = -reg.
    827     PoisonHeapReference(reg, reg);
    828   }
    829   // Unpoison a heap reference contained in `reg`.
    830   void UnpoisonHeapReference(GpuRegister reg) {
    831     // reg = -reg.
    832     // Negate the 32-bit ref.
    833     Dsubu(reg, ZERO, reg);
    834     // And constrain it to 32 bits (zero-extend into bits 32 through 63) as on Arm64 and x86/64.
    835     Dext(reg, reg, 0, 32);
    836   }
    837   // Poison a heap reference contained in `reg` if heap poisoning is enabled.
    838   void MaybePoisonHeapReference(GpuRegister reg) {
    839     if (kPoisonHeapReferences) {
    840       PoisonHeapReference(reg);
    841     }
    842   }
    843   // Unpoison a heap reference contained in `reg` if heap poisoning is enabled.
    844   void MaybeUnpoisonHeapReference(GpuRegister reg) {
    845     if (kPoisonHeapReferences) {
    846       UnpoisonHeapReference(reg);
    847     }
    848   }
    849 
    850   void Bind(Label* label) OVERRIDE {
    851     Bind(down_cast<Mips64Label*>(label));
    852   }
    853   void Jump(Label* label ATTRIBUTE_UNUSED) OVERRIDE {
    854     UNIMPLEMENTED(FATAL) << "Do not use Jump for MIPS64";
    855   }
    856 
    857   void Bind(Mips64Label* label);
    858 
    859   // Don't warn about a different virtual Bind/Jump in the base class.
    860   using JNIBase::Bind;
    861   using JNIBase::Jump;
    862 
    863   // Create a new label that can be used with Jump/Bind calls.
    864   std::unique_ptr<JNIMacroLabel> CreateLabel() OVERRIDE {
    865     LOG(FATAL) << "Not implemented on MIPS64";
    866     UNREACHABLE();
    867   }
    868   // Emit an unconditional jump to the label.
    869   void Jump(JNIMacroLabel* label ATTRIBUTE_UNUSED) OVERRIDE {
    870     LOG(FATAL) << "Not implemented on MIPS64";
    871     UNREACHABLE();
    872   }
    873   // Emit a conditional jump to the label by applying a unary condition test to the register.
    874   void Jump(JNIMacroLabel* label ATTRIBUTE_UNUSED,
    875             JNIMacroUnaryCondition cond ATTRIBUTE_UNUSED,
    876             ManagedRegister test ATTRIBUTE_UNUSED) OVERRIDE {
    877     LOG(FATAL) << "Not implemented on MIPS64";
    878     UNREACHABLE();
    879   }
    880 
    881   // Code at this offset will serve as the target for the Jump call.
    882   void Bind(JNIMacroLabel* label ATTRIBUTE_UNUSED) OVERRIDE {
    883     LOG(FATAL) << "Not implemented on MIPS64";
    884     UNREACHABLE();
    885   }
    886 
    887   // Create a new literal with a given value.
    888   // NOTE: Force the template parameter to be explicitly specified.
    889   template <typename T>
    890   Literal* NewLiteral(typename Identity<T>::type value) {
    891     static_assert(std::is_integral<T>::value, "T must be an integral type.");
    892     return NewLiteral(sizeof(value), reinterpret_cast<const uint8_t*>(&value));
    893   }
    894 
    895   // Load label address using PC-relative loads. To be used with data labels in the literal /
    896   // jump table area only and not with regular code labels.
    897   void LoadLabelAddress(GpuRegister dest_reg, Mips64Label* label);
    898 
    899   // Create a new literal with the given data.
    900   Literal* NewLiteral(size_t size, const uint8_t* data);
    901 
    902   // Load literal using PC-relative loads.
    903   void LoadLiteral(GpuRegister dest_reg, LoadOperandType load_type, Literal* literal);
    904 
    905   // Create a jump table for the given labels that will be emitted when finalizing.
    906   // When the table is emitted, offsets will be relative to the location of the table.
    907   // The table location is determined by the location of its label (the label precedes
    908   // the table data) and should be loaded using LoadLabelAddress().
    909   JumpTable* CreateJumpTable(std::vector<Mips64Label*>&& labels);
    910 
    911   void Bc(Mips64Label* label);
    912   void Balc(Mips64Label* label);
    913   void Bltc(GpuRegister rs, GpuRegister rt, Mips64Label* label);
    914   void Bltzc(GpuRegister rt, Mips64Label* label);
    915   void Bgtzc(GpuRegister rt, Mips64Label* label);
    916   void Bgec(GpuRegister rs, GpuRegister rt, Mips64Label* label);
    917   void Bgezc(GpuRegister rt, Mips64Label* label);
    918   void Blezc(GpuRegister rt, Mips64Label* label);
    919   void Bltuc(GpuRegister rs, GpuRegister rt, Mips64Label* label);
    920   void Bgeuc(GpuRegister rs, GpuRegister rt, Mips64Label* label);
    921   void Beqc(GpuRegister rs, GpuRegister rt, Mips64Label* label);
    922   void Bnec(GpuRegister rs, GpuRegister rt, Mips64Label* label);
    923   void Beqzc(GpuRegister rs, Mips64Label* label);
    924   void Bnezc(GpuRegister rs, Mips64Label* label);
    925   void Bc1eqz(FpuRegister ft, Mips64Label* label);
    926   void Bc1nez(FpuRegister ft, Mips64Label* label);
    927 
    928   void EmitLoad(ManagedRegister m_dst, GpuRegister src_register, int32_t src_offset, size_t size);
    929   void AdjustBaseAndOffset(GpuRegister& base, int32_t& offset, bool is_doubleword);
    930   // If element_size_shift is negative at entry, its value will be calculated based on the offset.
    931   void AdjustBaseOffsetAndElementSizeShift(GpuRegister& base,
    932                                            int32_t& offset,
    933                                            int& element_size_shift);
    934 
    935  private:
    936   // This will be used as an argument for loads/stores
    937   // when there is no need for implicit null checks.
    938   struct NoImplicitNullChecker {
    939     void operator()() const {}
    940   };
    941 
    942  public:
    943   template <typename ImplicitNullChecker = NoImplicitNullChecker>
    944   void StoreConstToOffset(StoreOperandType type,
    945                           int64_t value,
    946                           GpuRegister base,
    947                           int32_t offset,
    948                           GpuRegister temp,
    949                           ImplicitNullChecker null_checker = NoImplicitNullChecker()) {
    950     // We permit `base` and `temp` to coincide (however, we check that neither is AT),
    951     // in which case the `base` register may be overwritten in the process.
    952     CHECK_NE(temp, AT);  // Must not use AT as temp, so as not to overwrite the adjusted base.
    953     AdjustBaseAndOffset(base, offset, /* is_doubleword */ (type == kStoreDoubleword));
    954     GpuRegister reg;
    955     // If the adjustment left `base` unchanged and equal to `temp`, we can't use `temp`
    956     // to load and hold the value but we can use AT instead as AT hasn't been used yet.
    957     // Otherwise, `temp` can be used for the value. And if `temp` is the same as the
    958     // original `base` (that is, `base` prior to the adjustment), the original `base`
    959     // register will be overwritten.
    960     if (base == temp) {
    961       temp = AT;
    962     }
    963 
    964     if (type == kStoreDoubleword && IsAligned<kMips64DoublewordSize>(offset)) {
    965       if (value == 0) {
    966         reg = ZERO;
    967       } else {
    968         reg = temp;
    969         LoadConst64(reg, value);
    970       }
    971       Sd(reg, base, offset);
    972       null_checker();
    973     } else {
    974       uint32_t low = Low32Bits(value);
    975       uint32_t high = High32Bits(value);
    976       if (low == 0) {
    977         reg = ZERO;
    978       } else {
    979         reg = temp;
    980         LoadConst32(reg, low);
    981       }
    982       switch (type) {
    983         case kStoreByte:
    984           Sb(reg, base, offset);
    985           break;
    986         case kStoreHalfword:
    987           Sh(reg, base, offset);
    988           break;
    989         case kStoreWord:
    990           Sw(reg, base, offset);
    991           break;
    992         case kStoreDoubleword:
    993           // not aligned to kMips64DoublewordSize
    994           CHECK_ALIGNED(offset, kMips64WordSize);
    995           Sw(reg, base, offset);
    996           null_checker();
    997           if (high == 0) {
    998             reg = ZERO;
    999           } else {
   1000             reg = temp;
   1001             if (high != low) {
   1002               LoadConst32(reg, high);
   1003             }
   1004           }
   1005           Sw(reg, base, offset + kMips64WordSize);
   1006           break;
   1007         default:
   1008           LOG(FATAL) << "UNREACHABLE";
   1009       }
   1010       if (type != kStoreDoubleword) {
   1011         null_checker();
   1012       }
   1013     }
   1014   }
   1015 
   1016   template <typename ImplicitNullChecker = NoImplicitNullChecker>
   1017   void LoadFromOffset(LoadOperandType type,
   1018                       GpuRegister reg,
   1019                       GpuRegister base,
   1020                       int32_t offset,
   1021                       ImplicitNullChecker null_checker = NoImplicitNullChecker()) {
   1022     AdjustBaseAndOffset(base, offset, /* is_doubleword */ (type == kLoadDoubleword));
   1023 
   1024     switch (type) {
   1025       case kLoadSignedByte:
   1026         Lb(reg, base, offset);
   1027         break;
   1028       case kLoadUnsignedByte:
   1029         Lbu(reg, base, offset);
   1030         break;
   1031       case kLoadSignedHalfword:
   1032         Lh(reg, base, offset);
   1033         break;
   1034       case kLoadUnsignedHalfword:
   1035         Lhu(reg, base, offset);
   1036         break;
   1037       case kLoadWord:
   1038         CHECK_ALIGNED(offset, kMips64WordSize);
   1039         Lw(reg, base, offset);
   1040         break;
   1041       case kLoadUnsignedWord:
   1042         CHECK_ALIGNED(offset, kMips64WordSize);
   1043         Lwu(reg, base, offset);
   1044         break;
   1045       case kLoadDoubleword:
   1046         if (!IsAligned<kMips64DoublewordSize>(offset)) {
   1047           CHECK_ALIGNED(offset, kMips64WordSize);
   1048           Lwu(reg, base, offset);
   1049           null_checker();
   1050           Lwu(TMP2, base, offset + kMips64WordSize);
   1051           Dinsu(reg, TMP2, 32, 32);
   1052         } else {
   1053           Ld(reg, base, offset);
   1054           null_checker();
   1055         }
   1056         break;
   1057       default:
   1058         LOG(FATAL) << "UNREACHABLE";
   1059     }
   1060     if (type != kLoadDoubleword) {
   1061       null_checker();
   1062     }
   1063   }
   1064 
   1065   template <typename ImplicitNullChecker = NoImplicitNullChecker>
   1066   void LoadFpuFromOffset(LoadOperandType type,
   1067                          FpuRegister reg,
   1068                          GpuRegister base,
   1069                          int32_t offset,
   1070                          ImplicitNullChecker null_checker = NoImplicitNullChecker()) {
   1071     int element_size_shift = -1;
   1072     if (type != kLoadQuadword) {
   1073       AdjustBaseAndOffset(base, offset, /* is_doubleword */ (type == kLoadDoubleword));
   1074     } else {
   1075       AdjustBaseOffsetAndElementSizeShift(base, offset, element_size_shift);
   1076     }
   1077 
   1078     switch (type) {
   1079       case kLoadWord:
   1080         CHECK_ALIGNED(offset, kMips64WordSize);
   1081         Lwc1(reg, base, offset);
   1082         null_checker();
   1083         break;
   1084       case kLoadDoubleword:
   1085         if (!IsAligned<kMips64DoublewordSize>(offset)) {
   1086           CHECK_ALIGNED(offset, kMips64WordSize);
   1087           Lwc1(reg, base, offset);
   1088           null_checker();
   1089           Lw(TMP2, base, offset + kMips64WordSize);
   1090           Mthc1(TMP2, reg);
   1091         } else {
   1092           Ldc1(reg, base, offset);
   1093           null_checker();
   1094         }
   1095         break;
   1096       case kLoadQuadword:
   1097         switch (element_size_shift) {
   1098           case TIMES_1: LdB(static_cast<VectorRegister>(reg), base, offset); break;
   1099           case TIMES_2: LdH(static_cast<VectorRegister>(reg), base, offset); break;
   1100           case TIMES_4: LdW(static_cast<VectorRegister>(reg), base, offset); break;
   1101           case TIMES_8: LdD(static_cast<VectorRegister>(reg), base, offset); break;
   1102           default:
   1103             LOG(FATAL) << "UNREACHABLE";
   1104         }
   1105         null_checker();
   1106         break;
   1107       default:
   1108         LOG(FATAL) << "UNREACHABLE";
   1109     }
   1110   }
   1111 
   1112   template <typename ImplicitNullChecker = NoImplicitNullChecker>
   1113   void StoreToOffset(StoreOperandType type,
   1114                      GpuRegister reg,
   1115                      GpuRegister base,
   1116                      int32_t offset,
   1117                      ImplicitNullChecker null_checker = NoImplicitNullChecker()) {
   1118     // Must not use AT as `reg`, so as not to overwrite the value being stored
   1119     // with the adjusted `base`.
   1120     CHECK_NE(reg, AT);
   1121     AdjustBaseAndOffset(base, offset, /* is_doubleword */ (type == kStoreDoubleword));
   1122 
   1123     switch (type) {
   1124       case kStoreByte:
   1125         Sb(reg, base, offset);
   1126         break;
   1127       case kStoreHalfword:
   1128         Sh(reg, base, offset);
   1129         break;
   1130       case kStoreWord:
   1131         CHECK_ALIGNED(offset, kMips64WordSize);
   1132         Sw(reg, base, offset);
   1133         break;
   1134       case kStoreDoubleword:
   1135         if (!IsAligned<kMips64DoublewordSize>(offset)) {
   1136           CHECK_ALIGNED(offset, kMips64WordSize);
   1137           Sw(reg, base, offset);
   1138           null_checker();
   1139           Dsrl32(TMP2, reg, 0);
   1140           Sw(TMP2, base, offset + kMips64WordSize);
   1141         } else {
   1142           Sd(reg, base, offset);
   1143           null_checker();
   1144         }
   1145         break;
   1146       default:
   1147         LOG(FATAL) << "UNREACHABLE";
   1148     }
   1149     if (type != kStoreDoubleword) {
   1150       null_checker();
   1151     }
   1152   }
   1153 
   1154   template <typename ImplicitNullChecker = NoImplicitNullChecker>
   1155   void StoreFpuToOffset(StoreOperandType type,
   1156                         FpuRegister reg,
   1157                         GpuRegister base,
   1158                         int32_t offset,
   1159                         ImplicitNullChecker null_checker = NoImplicitNullChecker()) {
   1160     int element_size_shift = -1;
   1161     if (type != kStoreQuadword) {
   1162       AdjustBaseAndOffset(base, offset, /* is_doubleword */ (type == kStoreDoubleword));
   1163     } else {
   1164       AdjustBaseOffsetAndElementSizeShift(base, offset, element_size_shift);
   1165     }
   1166 
   1167     switch (type) {
   1168       case kStoreWord:
   1169         CHECK_ALIGNED(offset, kMips64WordSize);
   1170         Swc1(reg, base, offset);
   1171         null_checker();
   1172         break;
   1173       case kStoreDoubleword:
   1174         if (!IsAligned<kMips64DoublewordSize>(offset)) {
   1175           CHECK_ALIGNED(offset, kMips64WordSize);
   1176           Mfhc1(TMP2, reg);
   1177           Swc1(reg, base, offset);
   1178           null_checker();
   1179           Sw(TMP2, base, offset + kMips64WordSize);
   1180         } else {
   1181           Sdc1(reg, base, offset);
   1182           null_checker();
   1183         }
   1184         break;
   1185       case kStoreQuadword:
   1186         switch (element_size_shift) {
   1187           case TIMES_1: StB(static_cast<VectorRegister>(reg), base, offset); break;
   1188           case TIMES_2: StH(static_cast<VectorRegister>(reg), base, offset); break;
   1189           case TIMES_4: StW(static_cast<VectorRegister>(reg), base, offset); break;
   1190           case TIMES_8: StD(static_cast<VectorRegister>(reg), base, offset); break;
   1191           default:
   1192             LOG(FATAL) << "UNREACHABLE";
   1193         }
   1194         null_checker();
   1195         break;
   1196       default:
   1197         LOG(FATAL) << "UNREACHABLE";
   1198     }
   1199   }
   1200 
   1201   void LoadFromOffset(LoadOperandType type, GpuRegister reg, GpuRegister base, int32_t offset);
   1202   void LoadFpuFromOffset(LoadOperandType type, FpuRegister reg, GpuRegister base, int32_t offset);
   1203   void StoreToOffset(StoreOperandType type, GpuRegister reg, GpuRegister base, int32_t offset);
   1204   void StoreFpuToOffset(StoreOperandType type, FpuRegister reg, GpuRegister base, int32_t offset);
   1205 
   1206   // Emit data (e.g. encoded instruction or immediate) to the instruction stream.
   1207   void Emit(uint32_t value);
   1208 
   1209   //
   1210   // Overridden common assembler high-level functionality.
   1211   //
   1212 
   1213   // Emit code that will create an activation on the stack.
   1214   void BuildFrame(size_t frame_size,
   1215                   ManagedRegister method_reg,
   1216                   ArrayRef<const ManagedRegister> callee_save_regs,
   1217                   const ManagedRegisterEntrySpills& entry_spills) OVERRIDE;
   1218 
   1219   // Emit code that will remove an activation from the stack.
   1220   void RemoveFrame(size_t frame_size, ArrayRef<const ManagedRegister> callee_save_regs) OVERRIDE;
   1221 
   1222   void IncreaseFrameSize(size_t adjust) OVERRIDE;
   1223   void DecreaseFrameSize(size_t adjust) OVERRIDE;
   1224 
   1225   // Store routines.
   1226   void Store(FrameOffset offs, ManagedRegister msrc, size_t size) OVERRIDE;
   1227   void StoreRef(FrameOffset dest, ManagedRegister msrc) OVERRIDE;
   1228   void StoreRawPtr(FrameOffset dest, ManagedRegister msrc) OVERRIDE;
   1229 
   1230   void StoreImmediateToFrame(FrameOffset dest, uint32_t imm, ManagedRegister mscratch) OVERRIDE;
   1231 
   1232   void StoreStackOffsetToThread(ThreadOffset64 thr_offs,
   1233                                 FrameOffset fr_offs,
   1234                                 ManagedRegister mscratch) OVERRIDE;
   1235 
   1236   void StoreStackPointerToThread(ThreadOffset64 thr_offs) OVERRIDE;
   1237 
   1238   void StoreSpanning(FrameOffset dest, ManagedRegister msrc, FrameOffset in_off,
   1239                      ManagedRegister mscratch) OVERRIDE;
   1240 
   1241   // Load routines.
   1242   void Load(ManagedRegister mdest, FrameOffset src, size_t size) OVERRIDE;
   1243 
   1244   void LoadFromThread(ManagedRegister mdest, ThreadOffset64 src, size_t size) OVERRIDE;
   1245 
   1246   void LoadRef(ManagedRegister dest, FrameOffset src) OVERRIDE;
   1247 
   1248   void LoadRef(ManagedRegister mdest, ManagedRegister base, MemberOffset offs,
   1249                bool unpoison_reference) OVERRIDE;
   1250 
   1251   void LoadRawPtr(ManagedRegister mdest, ManagedRegister base, Offset offs) OVERRIDE;
   1252 
   1253   void LoadRawPtrFromThread(ManagedRegister mdest, ThreadOffset64 offs) OVERRIDE;
   1254 
   1255   // Copying routines.
   1256   void Move(ManagedRegister mdest, ManagedRegister msrc, size_t size) OVERRIDE;
   1257 
   1258   void CopyRawPtrFromThread(FrameOffset fr_offs,
   1259                             ThreadOffset64 thr_offs,
   1260                             ManagedRegister mscratch) OVERRIDE;
   1261 
   1262   void CopyRawPtrToThread(ThreadOffset64 thr_offs,
   1263                           FrameOffset fr_offs,
   1264                           ManagedRegister mscratch) OVERRIDE;
   1265 
   1266   void CopyRef(FrameOffset dest, FrameOffset src, ManagedRegister mscratch) OVERRIDE;
   1267 
   1268   void Copy(FrameOffset dest, FrameOffset src, ManagedRegister mscratch, size_t size) OVERRIDE;
   1269 
   1270   void Copy(FrameOffset dest, ManagedRegister src_base, Offset src_offset, ManagedRegister mscratch,
   1271             size_t size) OVERRIDE;
   1272 
   1273   void Copy(ManagedRegister dest_base, Offset dest_offset, FrameOffset src,
   1274             ManagedRegister mscratch, size_t size) OVERRIDE;
   1275 
   1276   void Copy(FrameOffset dest, FrameOffset src_base, Offset src_offset, ManagedRegister mscratch,
   1277             size_t size) OVERRIDE;
   1278 
   1279   void Copy(ManagedRegister dest, Offset dest_offset, ManagedRegister src, Offset src_offset,
   1280             ManagedRegister mscratch, size_t size) OVERRIDE;
   1281 
   1282   void Copy(FrameOffset dest, Offset dest_offset, FrameOffset src, Offset src_offset,
   1283             ManagedRegister mscratch, size_t size) OVERRIDE;
   1284 
   1285   void MemoryBarrier(ManagedRegister) OVERRIDE;
   1286 
   1287   // Sign extension.
   1288   void SignExtend(ManagedRegister mreg, size_t size) OVERRIDE;
   1289 
   1290   // Zero extension.
   1291   void ZeroExtend(ManagedRegister mreg, size_t size) OVERRIDE;
   1292 
   1293   // Exploit fast access in managed code to Thread::Current().
   1294   void GetCurrentThread(ManagedRegister tr) OVERRIDE;
   1295   void GetCurrentThread(FrameOffset dest_offset, ManagedRegister mscratch) OVERRIDE;
   1296 
   1297   // Set up out_reg to hold a Object** into the handle scope, or to be null if the
   1298   // value is null and null_allowed. in_reg holds a possibly stale reference
   1299   // that can be used to avoid loading the handle scope entry to see if the value is
   1300   // null.
   1301   void CreateHandleScopeEntry(ManagedRegister out_reg, FrameOffset handlescope_offset,
   1302                               ManagedRegister in_reg, bool null_allowed) OVERRIDE;
   1303 
   1304   // Set up out_off to hold a Object** into the handle scope, or to be null if the
   1305   // value is null and null_allowed.
   1306   void CreateHandleScopeEntry(FrameOffset out_off, FrameOffset handlescope_offset, ManagedRegister
   1307                               mscratch, bool null_allowed) OVERRIDE;
   1308 
   1309   // src holds a handle scope entry (Object**) load this into dst.
   1310   void LoadReferenceFromHandleScope(ManagedRegister dst, ManagedRegister src) OVERRIDE;
   1311 
   1312   // Heap::VerifyObject on src. In some cases (such as a reference to this) we
   1313   // know that src may not be null.
   1314   void VerifyObject(ManagedRegister src, bool could_be_null) OVERRIDE;
   1315   void VerifyObject(FrameOffset src, bool could_be_null) OVERRIDE;
   1316 
   1317   // Call to address held at [base+offset].
   1318   void Call(ManagedRegister base, Offset offset, ManagedRegister mscratch) OVERRIDE;
   1319   void Call(FrameOffset base, Offset offset, ManagedRegister mscratch) OVERRIDE;
   1320   void CallFromThread(ThreadOffset64 offset, ManagedRegister mscratch) OVERRIDE;
   1321 
   1322   // Generate code to check if Thread::Current()->exception_ is non-null
   1323   // and branch to a ExceptionSlowPath if it is.
   1324   void ExceptionPoll(ManagedRegister mscratch, size_t stack_adjust) OVERRIDE;
   1325 
   1326   // Emit slow paths queued during assembly and promote short branches to long if needed.
   1327   void FinalizeCode() OVERRIDE;
   1328 
   1329   // Emit branches and finalize all instructions.
   1330   void FinalizeInstructions(const MemoryRegion& region);
   1331 
   1332   // Returns the (always-)current location of a label (can be used in class CodeGeneratorMIPS64,
   1333   // must be used instead of Mips64Label::GetPosition()).
   1334   uint32_t GetLabelLocation(const Mips64Label* label) const;
   1335 
   1336   // Get the final position of a label after local fixup based on the old position
   1337   // recorded before FinalizeCode().
   1338   uint32_t GetAdjustedPosition(uint32_t old_position);
   1339 
   1340   // Note that PC-relative literal loads are handled as pseudo branches because they need very
   1341   // similar relocation and may similarly expand in size to accomodate for larger offsets relative
   1342   // to PC.
   1343   enum BranchCondition {
   1344     kCondLT,
   1345     kCondGE,
   1346     kCondLE,
   1347     kCondGT,
   1348     kCondLTZ,
   1349     kCondGEZ,
   1350     kCondLEZ,
   1351     kCondGTZ,
   1352     kCondEQ,
   1353     kCondNE,
   1354     kCondEQZ,
   1355     kCondNEZ,
   1356     kCondLTU,
   1357     kCondGEU,
   1358     kCondF,    // Floating-point predicate false.
   1359     kCondT,    // Floating-point predicate true.
   1360     kUncond,
   1361   };
   1362   friend std::ostream& operator<<(std::ostream& os, const BranchCondition& rhs);
   1363 
   1364  private:
   1365   class Branch {
   1366    public:
   1367     enum Type {
   1368       // Short branches.
   1369       kUncondBranch,
   1370       kCondBranch,
   1371       kCall,
   1372       // Near label.
   1373       kLabel,
   1374       // Near literals.
   1375       kLiteral,
   1376       kLiteralUnsigned,
   1377       kLiteralLong,
   1378       // Long branches.
   1379       kLongUncondBranch,
   1380       kLongCondBranch,
   1381       kLongCall,
   1382       // Far label.
   1383       kFarLabel,
   1384       // Far literals.
   1385       kFarLiteral,
   1386       kFarLiteralUnsigned,
   1387       kFarLiteralLong,
   1388     };
   1389 
   1390     // Bit sizes of offsets defined as enums to minimize chance of typos.
   1391     enum OffsetBits {
   1392       kOffset16 = 16,
   1393       kOffset18 = 18,
   1394       kOffset21 = 21,
   1395       kOffset23 = 23,
   1396       kOffset28 = 28,
   1397       kOffset32 = 32,
   1398     };
   1399 
   1400     static constexpr uint32_t kUnresolved = 0xffffffff;  // Unresolved target_
   1401     static constexpr int32_t kMaxBranchLength = 32;
   1402     static constexpr int32_t kMaxBranchSize = kMaxBranchLength * sizeof(uint32_t);
   1403 
   1404     struct BranchInfo {
   1405       // Branch length as a number of 4-byte-long instructions.
   1406       uint32_t length;
   1407       // Ordinal number (0-based) of the first (or the only) instruction that contains the branch's
   1408       // PC-relative offset (or its most significant 16-bit half, which goes first).
   1409       uint32_t instr_offset;
   1410       // Different MIPS instructions with PC-relative offsets apply said offsets to slightly
   1411       // different origins, e.g. to PC or PC+4. Encode the origin distance (as a number of 4-byte
   1412       // instructions) from the instruction containing the offset.
   1413       uint32_t pc_org;
   1414       // How large (in bits) a PC-relative offset can be for a given type of branch (kCondBranch is
   1415       // an exception: use kOffset23 for beqzc/bnezc).
   1416       OffsetBits offset_size;
   1417       // Some MIPS instructions with PC-relative offsets shift the offset by 2. Encode the shift
   1418       // count.
   1419       int offset_shift;
   1420     };
   1421     static const BranchInfo branch_info_[/* Type */];
   1422 
   1423     // Unconditional branch or call.
   1424     Branch(uint32_t location, uint32_t target, bool is_call);
   1425     // Conditional branch.
   1426     Branch(uint32_t location,
   1427            uint32_t target,
   1428            BranchCondition condition,
   1429            GpuRegister lhs_reg,
   1430            GpuRegister rhs_reg);
   1431     // Label address (in literal area) or literal.
   1432     Branch(uint32_t location, GpuRegister dest_reg, Type label_or_literal_type);
   1433 
   1434     // Some conditional branches with lhs = rhs are effectively NOPs, while some
   1435     // others are effectively unconditional. MIPSR6 conditional branches require lhs != rhs.
   1436     // So, we need a way to identify such branches in order to emit no instructions for them
   1437     // or change them to unconditional.
   1438     static bool IsNop(BranchCondition condition, GpuRegister lhs, GpuRegister rhs);
   1439     static bool IsUncond(BranchCondition condition, GpuRegister lhs, GpuRegister rhs);
   1440 
   1441     static BranchCondition OppositeCondition(BranchCondition cond);
   1442 
   1443     Type GetType() const;
   1444     BranchCondition GetCondition() const;
   1445     GpuRegister GetLeftRegister() const;
   1446     GpuRegister GetRightRegister() const;
   1447     uint32_t GetTarget() const;
   1448     uint32_t GetLocation() const;
   1449     uint32_t GetOldLocation() const;
   1450     uint32_t GetLength() const;
   1451     uint32_t GetOldLength() const;
   1452     uint32_t GetSize() const;
   1453     uint32_t GetOldSize() const;
   1454     uint32_t GetEndLocation() const;
   1455     uint32_t GetOldEndLocation() const;
   1456     bool IsLong() const;
   1457     bool IsResolved() const;
   1458 
   1459     // Returns the bit size of the signed offset that the branch instruction can handle.
   1460     OffsetBits GetOffsetSize() const;
   1461 
   1462     // Calculates the distance between two byte locations in the assembler buffer and
   1463     // returns the number of bits needed to represent the distance as a signed integer.
   1464     //
   1465     // Branch instructions have signed offsets of 16, 19 (addiupc), 21 (beqzc/bnezc),
   1466     // and 26 (bc) bits, which are additionally shifted left 2 positions at run time.
   1467     //
   1468     // Composite branches (made of several instructions) with longer reach have 32-bit
   1469     // offsets encoded as 2 16-bit "halves" in two instructions (high half goes first).
   1470     // The composite branches cover the range of PC + ~+/-2GB. The range is not end-to-end,
   1471     // however. Consider the following implementation of a long unconditional branch, for
   1472     // example:
   1473     //
   1474     //   auipc at, offset_31_16  // at = pc + sign_extend(offset_31_16) << 16
   1475     //   jic   at, offset_15_0   // pc = at + sign_extend(offset_15_0)
   1476     //
   1477     // Both of the above instructions take 16-bit signed offsets as immediate operands.
   1478     // When bit 15 of offset_15_0 is 1, it effectively causes subtraction of 0x10000
   1479     // due to sign extension. This must be compensated for by incrementing offset_31_16
   1480     // by 1. offset_31_16 can only be incremented by 1 if it's not 0x7FFF. If it is
   1481     // 0x7FFF, adding 1 will overflow the positive offset into the negative range.
   1482     // Therefore, the long branch range is something like from PC - 0x80000000 to
   1483     // PC + 0x7FFF7FFF, IOW, shorter by 32KB on one side.
   1484     //
   1485     // The returned values are therefore: 18, 21, 23, 28 and 32. There's also a special
   1486     // case with the addiu instruction and a 16 bit offset.
   1487     static OffsetBits GetOffsetSizeNeeded(uint32_t location, uint32_t target);
   1488 
   1489     // Resolve a branch when the target is known.
   1490     void Resolve(uint32_t target);
   1491 
   1492     // Relocate a branch by a given delta if needed due to expansion of this or another
   1493     // branch at a given location by this delta (just changes location_ and target_).
   1494     void Relocate(uint32_t expand_location, uint32_t delta);
   1495 
   1496     // If the branch is short, changes its type to long.
   1497     void PromoteToLong();
   1498 
   1499     // If necessary, updates the type by promoting a short branch to a long branch
   1500     // based on the branch location and target. Returns the amount (in bytes) by
   1501     // which the branch size has increased.
   1502     // max_short_distance caps the maximum distance between location_ and target_
   1503     // that is allowed for short branches. This is for debugging/testing purposes.
   1504     // max_short_distance = 0 forces all short branches to become long.
   1505     // Use the implicit default argument when not debugging/testing.
   1506     uint32_t PromoteIfNeeded(uint32_t max_short_distance = std::numeric_limits<uint32_t>::max());
   1507 
   1508     // Returns the location of the instruction(s) containing the offset.
   1509     uint32_t GetOffsetLocation() const;
   1510 
   1511     // Calculates and returns the offset ready for encoding in the branch instruction(s).
   1512     uint32_t GetOffset() const;
   1513 
   1514    private:
   1515     // Completes branch construction by determining and recording its type.
   1516     void InitializeType(Type initial_type);
   1517     // Helper for the above.
   1518     void InitShortOrLong(OffsetBits ofs_size, Type short_type, Type long_type);
   1519 
   1520     uint32_t old_location_;      // Offset into assembler buffer in bytes.
   1521     uint32_t location_;          // Offset into assembler buffer in bytes.
   1522     uint32_t target_;            // Offset into assembler buffer in bytes.
   1523 
   1524     GpuRegister lhs_reg_;        // Left-hand side register in conditional branches or
   1525                                  // destination register in literals.
   1526     GpuRegister rhs_reg_;        // Right-hand side register in conditional branches.
   1527     BranchCondition condition_;  // Condition for conditional branches.
   1528 
   1529     Type type_;                  // Current type of the branch.
   1530     Type old_type_;              // Initial type of the branch.
   1531   };
   1532   friend std::ostream& operator<<(std::ostream& os, const Branch::Type& rhs);
   1533   friend std::ostream& operator<<(std::ostream& os, const Branch::OffsetBits& rhs);
   1534 
   1535   void EmitR(int opcode, GpuRegister rs, GpuRegister rt, GpuRegister rd, int shamt, int funct);
   1536   void EmitRsd(int opcode, GpuRegister rs, GpuRegister rd, int shamt, int funct);
   1537   void EmitRtd(int opcode, GpuRegister rt, GpuRegister rd, int shamt, int funct);
   1538   void EmitI(int opcode, GpuRegister rs, GpuRegister rt, uint16_t imm);
   1539   void EmitI21(int opcode, GpuRegister rs, uint32_t imm21);
   1540   void EmitI26(int opcode, uint32_t imm26);
   1541   void EmitFR(int opcode, int fmt, FpuRegister ft, FpuRegister fs, FpuRegister fd, int funct);
   1542   void EmitFI(int opcode, int fmt, FpuRegister rt, uint16_t imm);
   1543   void EmitBcondc(BranchCondition cond, GpuRegister rs, GpuRegister rt, uint32_t imm16_21);
   1544   void EmitMsa3R(int operation,
   1545                  int df,
   1546                  VectorRegister wt,
   1547                  VectorRegister ws,
   1548                  VectorRegister wd,
   1549                  int minor_opcode);
   1550   void EmitMsaBIT(int operation, int df_m, VectorRegister ws, VectorRegister wd, int minor_opcode);
   1551   void EmitMsaELM(int operation, int df_n, VectorRegister ws, VectorRegister wd, int minor_opcode);
   1552   void EmitMsaMI10(int s10, GpuRegister rs, VectorRegister wd, int minor_opcode, int df);
   1553   void EmitMsaI10(int operation, int df, int i10, VectorRegister wd, int minor_opcode);
   1554   void EmitMsa2R(int operation, int df, VectorRegister ws, VectorRegister wd, int minor_opcode);
   1555   void EmitMsa2RF(int operation, int df, VectorRegister ws, VectorRegister wd, int minor_opcode);
   1556 
   1557   void Buncond(Mips64Label* label);
   1558   void Bcond(Mips64Label* label,
   1559              BranchCondition condition,
   1560              GpuRegister lhs,
   1561              GpuRegister rhs = ZERO);
   1562   void Call(Mips64Label* label);
   1563   void FinalizeLabeledBranch(Mips64Label* label);
   1564 
   1565   Branch* GetBranch(uint32_t branch_id);
   1566   const Branch* GetBranch(uint32_t branch_id) const;
   1567 
   1568   void EmitLiterals();
   1569   void ReserveJumpTableSpace();
   1570   void EmitJumpTables();
   1571   void PromoteBranches();
   1572   void EmitBranch(Branch* branch);
   1573   void EmitBranches();
   1574   void PatchCFI();
   1575 
   1576   // Emits exception block.
   1577   void EmitExceptionPoll(Mips64ExceptionSlowPath* exception);
   1578 
   1579   bool HasMsa() const {
   1580     return has_msa_;
   1581   }
   1582 
   1583   // List of exception blocks to generate at the end of the code cache.
   1584   std::vector<Mips64ExceptionSlowPath> exception_blocks_;
   1585 
   1586   std::vector<Branch> branches_;
   1587 
   1588   // Whether appending instructions at the end of the buffer or overwriting the existing ones.
   1589   bool overwriting_;
   1590   // The current overwrite location.
   1591   uint32_t overwrite_location_;
   1592 
   1593   // Use std::deque<> for literal labels to allow insertions at the end
   1594   // without invalidating pointers and references to existing elements.
   1595   ArenaDeque<Literal> literals_;
   1596   ArenaDeque<Literal> long_literals_;  // 64-bit literals separated for alignment reasons.
   1597 
   1598   // Jump table list.
   1599   ArenaDeque<JumpTable> jump_tables_;
   1600 
   1601   // Data for AdjustedPosition(), see the description there.
   1602   uint32_t last_position_adjustment_;
   1603   uint32_t last_old_position_;
   1604   uint32_t last_branch_id_;
   1605 
   1606   const bool has_msa_;
   1607 
   1608   DISALLOW_COPY_AND_ASSIGN(Mips64Assembler);
   1609 };
   1610 
   1611 }  // namespace mips64
   1612 }  // namespace art
   1613 
   1614 #endif  // ART_COMPILER_UTILS_MIPS64_ASSEMBLER_MIPS64_H_
   1615