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      1 //===- AArch64AddressingModes.h - AArch64 Addressing Modes ------*- C++ -*-===//
      2 //
      3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
      4 // See https://llvm.org/LICENSE.txt for license information.
      5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
      6 //
      7 //===----------------------------------------------------------------------===//
      8 //
      9 // This file contains the AArch64 addressing mode implementation stuff.
     10 //
     11 //===----------------------------------------------------------------------===//
     12 
     13 #ifndef LLVM_LIB_TARGET_AARCH64_MCTARGETDESC_AARCH64ADDRESSINGMODES_H
     14 #define LLVM_LIB_TARGET_AARCH64_MCTARGETDESC_AARCH64ADDRESSINGMODES_H
     15 
     16 #include "llvm/ADT/APFloat.h"
     17 #include "llvm/ADT/APInt.h"
     18 #include "llvm/ADT/bit.h"
     19 #include "llvm/Support/ErrorHandling.h"
     20 #include "llvm/Support/MathExtras.h"
     21 #include <cassert>
     22 
     23 namespace llvm {
     24 
     25 /// AArch64_AM - AArch64 Addressing Mode Stuff
     26 namespace AArch64_AM {
     27 
     28 //===----------------------------------------------------------------------===//
     29 // Shifts
     30 //
     31 
     32 enum ShiftExtendType {
     33   InvalidShiftExtend = -1,
     34   LSL = 0,
     35   LSR,
     36   ASR,
     37   ROR,
     38   MSL,
     39 
     40   UXTB,
     41   UXTH,
     42   UXTW,
     43   UXTX,
     44 
     45   SXTB,
     46   SXTH,
     47   SXTW,
     48   SXTX,
     49 };
     50 
     51 /// getShiftName - Get the string encoding for the shift type.
     52 static inline const char *getShiftExtendName(AArch64_AM::ShiftExtendType ST) {
     53   switch (ST) {
     54   default: llvm_unreachable("unhandled shift type!");
     55   case AArch64_AM::LSL: return "lsl";
     56   case AArch64_AM::LSR: return "lsr";
     57   case AArch64_AM::ASR: return "asr";
     58   case AArch64_AM::ROR: return "ror";
     59   case AArch64_AM::MSL: return "msl";
     60   case AArch64_AM::UXTB: return "uxtb";
     61   case AArch64_AM::UXTH: return "uxth";
     62   case AArch64_AM::UXTW: return "uxtw";
     63   case AArch64_AM::UXTX: return "uxtx";
     64   case AArch64_AM::SXTB: return "sxtb";
     65   case AArch64_AM::SXTH: return "sxth";
     66   case AArch64_AM::SXTW: return "sxtw";
     67   case AArch64_AM::SXTX: return "sxtx";
     68   }
     69   return nullptr;
     70 }
     71 
     72 /// getShiftType - Extract the shift type.
     73 static inline AArch64_AM::ShiftExtendType getShiftType(unsigned Imm) {
     74   switch ((Imm >> 6) & 0x7) {
     75   default: return AArch64_AM::InvalidShiftExtend;
     76   case 0: return AArch64_AM::LSL;
     77   case 1: return AArch64_AM::LSR;
     78   case 2: return AArch64_AM::ASR;
     79   case 3: return AArch64_AM::ROR;
     80   case 4: return AArch64_AM::MSL;
     81   }
     82 }
     83 
     84 /// getShiftValue - Extract the shift value.
     85 static inline unsigned getShiftValue(unsigned Imm) {
     86   return Imm & 0x3f;
     87 }
     88 
     89 /// getShifterImm - Encode the shift type and amount:
     90 ///   imm:     6-bit shift amount
     91 ///   shifter: 000 ==> lsl
     92 ///            001 ==> lsr
     93 ///            010 ==> asr
     94 ///            011 ==> ror
     95 ///            100 ==> msl
     96 ///   {8-6}  = shifter
     97 ///   {5-0}  = imm
     98 static inline unsigned getShifterImm(AArch64_AM::ShiftExtendType ST,
     99                                      unsigned Imm) {
    100   assert((Imm & 0x3f) == Imm && "Illegal shifted immedate value!");
    101   unsigned STEnc = 0;
    102   switch (ST) {
    103   default:  llvm_unreachable("Invalid shift requested");
    104   case AArch64_AM::LSL: STEnc = 0; break;
    105   case AArch64_AM::LSR: STEnc = 1; break;
    106   case AArch64_AM::ASR: STEnc = 2; break;
    107   case AArch64_AM::ROR: STEnc = 3; break;
    108   case AArch64_AM::MSL: STEnc = 4; break;
    109   }
    110   return (STEnc << 6) | (Imm & 0x3f);
    111 }
    112 
    113 //===----------------------------------------------------------------------===//
    114 // Extends
    115 //
    116 
    117 /// getArithShiftValue - get the arithmetic shift value.
    118 static inline unsigned getArithShiftValue(unsigned Imm) {
    119   return Imm & 0x7;
    120 }
    121 
    122 /// getExtendType - Extract the extend type for operands of arithmetic ops.
    123 static inline AArch64_AM::ShiftExtendType getExtendType(unsigned Imm) {
    124   assert((Imm & 0x7) == Imm && "invalid immediate!");
    125   switch (Imm) {
    126   default: llvm_unreachable("Compiler bug!");
    127   case 0: return AArch64_AM::UXTB;
    128   case 1: return AArch64_AM::UXTH;
    129   case 2: return AArch64_AM::UXTW;
    130   case 3: return AArch64_AM::UXTX;
    131   case 4: return AArch64_AM::SXTB;
    132   case 5: return AArch64_AM::SXTH;
    133   case 6: return AArch64_AM::SXTW;
    134   case 7: return AArch64_AM::SXTX;
    135   }
    136 }
    137 
    138 static inline AArch64_AM::ShiftExtendType getArithExtendType(unsigned Imm) {
    139   return getExtendType((Imm >> 3) & 0x7);
    140 }
    141 
    142 /// Mapping from extend bits to required operation:
    143 ///   shifter: 000 ==> uxtb
    144 ///            001 ==> uxth
    145 ///            010 ==> uxtw
    146 ///            011 ==> uxtx
    147 ///            100 ==> sxtb
    148 ///            101 ==> sxth
    149 ///            110 ==> sxtw
    150 ///            111 ==> sxtx
    151 inline unsigned getExtendEncoding(AArch64_AM::ShiftExtendType ET) {
    152   switch (ET) {
    153   default: llvm_unreachable("Invalid extend type requested");
    154   case AArch64_AM::UXTB: return 0; break;
    155   case AArch64_AM::UXTH: return 1; break;
    156   case AArch64_AM::UXTW: return 2; break;
    157   case AArch64_AM::UXTX: return 3; break;
    158   case AArch64_AM::SXTB: return 4; break;
    159   case AArch64_AM::SXTH: return 5; break;
    160   case AArch64_AM::SXTW: return 6; break;
    161   case AArch64_AM::SXTX: return 7; break;
    162   }
    163 }
    164 
    165 /// getArithExtendImm - Encode the extend type and shift amount for an
    166 ///                     arithmetic instruction:
    167 ///   imm:     3-bit extend amount
    168 ///   {5-3}  = shifter
    169 ///   {2-0}  = imm3
    170 static inline unsigned getArithExtendImm(AArch64_AM::ShiftExtendType ET,
    171                                          unsigned Imm) {
    172   assert((Imm & 0x7) == Imm && "Illegal shifted immedate value!");
    173   return (getExtendEncoding(ET) << 3) | (Imm & 0x7);
    174 }
    175 
    176 /// getMemDoShift - Extract the "do shift" flag value for load/store
    177 /// instructions.
    178 static inline bool getMemDoShift(unsigned Imm) {
    179   return (Imm & 0x1) != 0;
    180 }
    181 
    182 /// getExtendType - Extract the extend type for the offset operand of
    183 /// loads/stores.
    184 static inline AArch64_AM::ShiftExtendType getMemExtendType(unsigned Imm) {
    185   return getExtendType((Imm >> 1) & 0x7);
    186 }
    187 
    188 /// getExtendImm - Encode the extend type and amount for a load/store inst:
    189 ///   doshift:     should the offset be scaled by the access size
    190 ///   shifter: 000 ==> uxtb
    191 ///            001 ==> uxth
    192 ///            010 ==> uxtw
    193 ///            011 ==> uxtx
    194 ///            100 ==> sxtb
    195 ///            101 ==> sxth
    196 ///            110 ==> sxtw
    197 ///            111 ==> sxtx
    198 ///   {3-1}  = shifter
    199 ///   {0}  = doshift
    200 static inline unsigned getMemExtendImm(AArch64_AM::ShiftExtendType ET,
    201                                        bool DoShift) {
    202   return (getExtendEncoding(ET) << 1) | unsigned(DoShift);
    203 }
    204 
    205 static inline uint64_t ror(uint64_t elt, unsigned size) {
    206   return ((elt & 1) << (size-1)) | (elt >> 1);
    207 }
    208 
    209 /// processLogicalImmediate - Determine if an immediate value can be encoded
    210 /// as the immediate operand of a logical instruction for the given register
    211 /// size.  If so, return true with "encoding" set to the encoded value in
    212 /// the form N:immr:imms.
    213 static inline bool processLogicalImmediate(uint64_t Imm, unsigned RegSize,
    214                                            uint64_t &Encoding) {
    215   if (Imm == 0ULL || Imm == ~0ULL ||
    216       (RegSize != 64 &&
    217         (Imm >> RegSize != 0 || Imm == (~0ULL >> (64 - RegSize)))))
    218     return false;
    219 
    220   // First, determine the element size.
    221   unsigned Size = RegSize;
    222 
    223   do {
    224     Size /= 2;
    225     uint64_t Mask = (1ULL << Size) - 1;
    226 
    227     if ((Imm & Mask) != ((Imm >> Size) & Mask)) {
    228       Size *= 2;
    229       break;
    230     }
    231   } while (Size > 2);
    232 
    233   // Second, determine the rotation to make the element be: 0^m 1^n.
    234   uint32_t CTO, I;
    235   uint64_t Mask = ((uint64_t)-1LL) >> (64 - Size);
    236   Imm &= Mask;
    237 
    238   if (isShiftedMask_64(Imm)) {
    239     I = countTrailingZeros(Imm);
    240     assert(I < 64 && "undefined behavior");
    241     CTO = countTrailingOnes(Imm >> I);
    242   } else {
    243     Imm |= ~Mask;
    244     if (!isShiftedMask_64(~Imm))
    245       return false;
    246 
    247     unsigned CLO = countLeadingOnes(Imm);
    248     I = 64 - CLO;
    249     CTO = CLO + countTrailingOnes(Imm) - (64 - Size);
    250   }
    251 
    252   // Encode in Immr the number of RORs it would take to get *from* 0^m 1^n
    253   // to our target value, where I is the number of RORs to go the opposite
    254   // direction.
    255   assert(Size > I && "I should be smaller than element size");
    256   unsigned Immr = (Size - I) & (Size - 1);
    257 
    258   // If size has a 1 in the n'th bit, create a value that has zeroes in
    259   // bits [0, n] and ones above that.
    260   uint64_t NImms = ~(Size-1) << 1;
    261 
    262   // Or the CTO value into the low bits, which must be below the Nth bit
    263   // bit mentioned above.
    264   NImms |= (CTO-1);
    265 
    266   // Extract the seventh bit and toggle it to create the N field.
    267   unsigned N = ((NImms >> 6) & 1) ^ 1;
    268 
    269   Encoding = (N << 12) | (Immr << 6) | (NImms & 0x3f);
    270   return true;
    271 }
    272 
    273 /// isLogicalImmediate - Return true if the immediate is valid for a logical
    274 /// immediate instruction of the given register size. Return false otherwise.
    275 static inline bool isLogicalImmediate(uint64_t imm, unsigned regSize) {
    276   uint64_t encoding;
    277   return processLogicalImmediate(imm, regSize, encoding);
    278 }
    279 
    280 /// encodeLogicalImmediate - Return the encoded immediate value for a logical
    281 /// immediate instruction of the given register size.
    282 static inline uint64_t encodeLogicalImmediate(uint64_t imm, unsigned regSize) {
    283   uint64_t encoding = 0;
    284   bool res = processLogicalImmediate(imm, regSize, encoding);
    285   assert(res && "invalid logical immediate");
    286   (void)res;
    287   return encoding;
    288 }
    289 
    290 /// decodeLogicalImmediate - Decode a logical immediate value in the form
    291 /// "N:immr:imms" (where the immr and imms fields are each 6 bits) into the
    292 /// integer value it represents with regSize bits.
    293 static inline uint64_t decodeLogicalImmediate(uint64_t val, unsigned regSize) {
    294   // Extract the N, imms, and immr fields.
    295   unsigned N = (val >> 12) & 1;
    296   unsigned immr = (val >> 6) & 0x3f;
    297   unsigned imms = val & 0x3f;
    298 
    299   assert((regSize == 64 || N == 0) && "undefined logical immediate encoding");
    300   int len = 31 - countLeadingZeros((N << 6) | (~imms & 0x3f));
    301   assert(len >= 0 && "undefined logical immediate encoding");
    302   unsigned size = (1 << len);
    303   unsigned R = immr & (size - 1);
    304   unsigned S = imms & (size - 1);
    305   assert(S != size - 1 && "undefined logical immediate encoding");
    306   uint64_t pattern = (1ULL << (S + 1)) - 1;
    307   for (unsigned i = 0; i < R; ++i)
    308     pattern = ror(pattern, size);
    309 
    310   // Replicate the pattern to fill the regSize.
    311   while (size != regSize) {
    312     pattern |= (pattern << size);
    313     size *= 2;
    314   }
    315   return pattern;
    316 }
    317 
    318 /// isValidDecodeLogicalImmediate - Check to see if the logical immediate value
    319 /// in the form "N:immr:imms" (where the immr and imms fields are each 6 bits)
    320 /// is a valid encoding for an integer value with regSize bits.
    321 static inline bool isValidDecodeLogicalImmediate(uint64_t val,
    322                                                  unsigned regSize) {
    323   // Extract the N and imms fields needed for checking.
    324   unsigned N = (val >> 12) & 1;
    325   unsigned imms = val & 0x3f;
    326 
    327   if (regSize == 32 && N != 0) // undefined logical immediate encoding
    328     return false;
    329   int len = 31 - countLeadingZeros((N << 6) | (~imms & 0x3f));
    330   if (len < 0) // undefined logical immediate encoding
    331     return false;
    332   unsigned size = (1 << len);
    333   unsigned S = imms & (size - 1);
    334   if (S == size - 1) // undefined logical immediate encoding
    335     return false;
    336 
    337   return true;
    338 }
    339 
    340 //===----------------------------------------------------------------------===//
    341 // Floating-point Immediates
    342 //
    343 static inline float getFPImmFloat(unsigned Imm) {
    344   // We expect an 8-bit binary encoding of a floating-point number here.
    345 
    346   uint8_t Sign = (Imm >> 7) & 0x1;
    347   uint8_t Exp = (Imm >> 4) & 0x7;
    348   uint8_t Mantissa = Imm & 0xf;
    349 
    350   //   8-bit FP    IEEE Float Encoding
    351   //   abcd efgh   aBbbbbbc defgh000 00000000 00000000
    352   //
    353   // where B = NOT(b);
    354 
    355   uint32_t I = 0;
    356   I |= Sign << 31;
    357   I |= ((Exp & 0x4) != 0 ? 0 : 1) << 30;
    358   I |= ((Exp & 0x4) != 0 ? 0x1f : 0) << 25;
    359   I |= (Exp & 0x3) << 23;
    360   I |= Mantissa << 19;
    361   return bit_cast<float>(I);
    362 }
    363 
    364 /// getFP16Imm - Return an 8-bit floating-point version of the 16-bit
    365 /// floating-point value. If the value cannot be represented as an 8-bit
    366 /// floating-point value, then return -1.
    367 static inline int getFP16Imm(const APInt &Imm) {
    368   uint32_t Sign = Imm.lshr(15).getZExtValue() & 1;
    369   int32_t Exp = (Imm.lshr(10).getSExtValue() & 0x1f) - 15;  // -14 to 15
    370   int32_t Mantissa = Imm.getZExtValue() & 0x3ff;  // 10 bits
    371 
    372   // We can handle 4 bits of mantissa.
    373   // mantissa = (16+UInt(e:f:g:h))/16.
    374   if (Mantissa & 0x3f)
    375     return -1;
    376   Mantissa >>= 6;
    377 
    378   // We can handle 3 bits of exponent: exp == UInt(NOT(b):c:d)-3
    379   if (Exp < -3 || Exp > 4)
    380     return -1;
    381   Exp = ((Exp+3) & 0x7) ^ 4;
    382 
    383   return ((int)Sign << 7) | (Exp << 4) | Mantissa;
    384 }
    385 
    386 static inline int getFP16Imm(const APFloat &FPImm) {
    387   return getFP16Imm(FPImm.bitcastToAPInt());
    388 }
    389 
    390 /// getFP32Imm - Return an 8-bit floating-point version of the 32-bit
    391 /// floating-point value. If the value cannot be represented as an 8-bit
    392 /// floating-point value, then return -1.
    393 static inline int getFP32Imm(const APInt &Imm) {
    394   uint32_t Sign = Imm.lshr(31).getZExtValue() & 1;
    395   int32_t Exp = (Imm.lshr(23).getSExtValue() & 0xff) - 127;  // -126 to 127
    396   int64_t Mantissa = Imm.getZExtValue() & 0x7fffff;  // 23 bits
    397 
    398   // We can handle 4 bits of mantissa.
    399   // mantissa = (16+UInt(e:f:g:h))/16.
    400   if (Mantissa & 0x7ffff)
    401     return -1;
    402   Mantissa >>= 19;
    403   if ((Mantissa & 0xf) != Mantissa)
    404     return -1;
    405 
    406   // We can handle 3 bits of exponent: exp == UInt(NOT(b):c:d)-3
    407   if (Exp < -3 || Exp > 4)
    408     return -1;
    409   Exp = ((Exp+3) & 0x7) ^ 4;
    410 
    411   return ((int)Sign << 7) | (Exp << 4) | Mantissa;
    412 }
    413 
    414 static inline int getFP32Imm(const APFloat &FPImm) {
    415   return getFP32Imm(FPImm.bitcastToAPInt());
    416 }
    417 
    418 /// getFP64Imm - Return an 8-bit floating-point version of the 64-bit
    419 /// floating-point value. If the value cannot be represented as an 8-bit
    420 /// floating-point value, then return -1.
    421 static inline int getFP64Imm(const APInt &Imm) {
    422   uint64_t Sign = Imm.lshr(63).getZExtValue() & 1;
    423   int64_t Exp = (Imm.lshr(52).getSExtValue() & 0x7ff) - 1023;   // -1022 to 1023
    424   uint64_t Mantissa = Imm.getZExtValue() & 0xfffffffffffffULL;
    425 
    426   // We can handle 4 bits of mantissa.
    427   // mantissa = (16+UInt(e:f:g:h))/16.
    428   if (Mantissa & 0xffffffffffffULL)
    429     return -1;
    430   Mantissa >>= 48;
    431   if ((Mantissa & 0xf) != Mantissa)
    432     return -1;
    433 
    434   // We can handle 3 bits of exponent: exp == UInt(NOT(b):c:d)-3
    435   if (Exp < -3 || Exp > 4)
    436     return -1;
    437   Exp = ((Exp+3) & 0x7) ^ 4;
    438 
    439   return ((int)Sign << 7) | (Exp << 4) | Mantissa;
    440 }
    441 
    442 static inline int getFP64Imm(const APFloat &FPImm) {
    443   return getFP64Imm(FPImm.bitcastToAPInt());
    444 }
    445 
    446 //===--------------------------------------------------------------------===//
    447 // AdvSIMD Modified Immediates
    448 //===--------------------------------------------------------------------===//
    449 
    450 // 0x00 0x00 0x00 abcdefgh 0x00 0x00 0x00 abcdefgh
    451 static inline bool isAdvSIMDModImmType1(uint64_t Imm) {
    452   return ((Imm >> 32) == (Imm & 0xffffffffULL)) &&
    453          ((Imm & 0xffffff00ffffff00ULL) == 0);
    454 }
    455 
    456 static inline uint8_t encodeAdvSIMDModImmType1(uint64_t Imm) {
    457   return (Imm & 0xffULL);
    458 }
    459 
    460 static inline uint64_t decodeAdvSIMDModImmType1(uint8_t Imm) {
    461   uint64_t EncVal = Imm;
    462   return (EncVal << 32) | EncVal;
    463 }
    464 
    465 // 0x00 0x00 abcdefgh 0x00 0x00 0x00 abcdefgh 0x00
    466 static inline bool isAdvSIMDModImmType2(uint64_t Imm) {
    467   return ((Imm >> 32) == (Imm & 0xffffffffULL)) &&
    468          ((Imm & 0xffff00ffffff00ffULL) == 0);
    469 }
    470 
    471 static inline uint8_t encodeAdvSIMDModImmType2(uint64_t Imm) {
    472   return (Imm & 0xff00ULL) >> 8;
    473 }
    474 
    475 static inline uint64_t decodeAdvSIMDModImmType2(uint8_t Imm) {
    476   uint64_t EncVal = Imm;
    477   return (EncVal << 40) | (EncVal << 8);
    478 }
    479 
    480 // 0x00 abcdefgh 0x00 0x00 0x00 abcdefgh 0x00 0x00
    481 static inline bool isAdvSIMDModImmType3(uint64_t Imm) {
    482   return ((Imm >> 32) == (Imm & 0xffffffffULL)) &&
    483          ((Imm & 0xff00ffffff00ffffULL) == 0);
    484 }
    485 
    486 static inline uint8_t encodeAdvSIMDModImmType3(uint64_t Imm) {
    487   return (Imm & 0xff0000ULL) >> 16;
    488 }
    489 
    490 static inline uint64_t decodeAdvSIMDModImmType3(uint8_t Imm) {
    491   uint64_t EncVal = Imm;
    492   return (EncVal << 48) | (EncVal << 16);
    493 }
    494 
    495 // abcdefgh 0x00 0x00 0x00 abcdefgh 0x00 0x00 0x00
    496 static inline bool isAdvSIMDModImmType4(uint64_t Imm) {
    497   return ((Imm >> 32) == (Imm & 0xffffffffULL)) &&
    498          ((Imm & 0x00ffffff00ffffffULL) == 0);
    499 }
    500 
    501 static inline uint8_t encodeAdvSIMDModImmType4(uint64_t Imm) {
    502   return (Imm & 0xff000000ULL) >> 24;
    503 }
    504 
    505 static inline uint64_t decodeAdvSIMDModImmType4(uint8_t Imm) {
    506   uint64_t EncVal = Imm;
    507   return (EncVal << 56) | (EncVal << 24);
    508 }
    509 
    510 // 0x00 abcdefgh 0x00 abcdefgh 0x00 abcdefgh 0x00 abcdefgh
    511 static inline bool isAdvSIMDModImmType5(uint64_t Imm) {
    512   return ((Imm >> 32) == (Imm & 0xffffffffULL)) &&
    513          (((Imm & 0x00ff0000ULL) >> 16) == (Imm & 0x000000ffULL)) &&
    514          ((Imm & 0xff00ff00ff00ff00ULL) == 0);
    515 }
    516 
    517 static inline uint8_t encodeAdvSIMDModImmType5(uint64_t Imm) {
    518   return (Imm & 0xffULL);
    519 }
    520 
    521 static inline uint64_t decodeAdvSIMDModImmType5(uint8_t Imm) {
    522   uint64_t EncVal = Imm;
    523   return (EncVal << 48) | (EncVal << 32) | (EncVal << 16) | EncVal;
    524 }
    525 
    526 // abcdefgh 0x00 abcdefgh 0x00 abcdefgh 0x00 abcdefgh 0x00
    527 static inline bool isAdvSIMDModImmType6(uint64_t Imm) {
    528   return ((Imm >> 32) == (Imm & 0xffffffffULL)) &&
    529          (((Imm & 0xff000000ULL) >> 16) == (Imm & 0x0000ff00ULL)) &&
    530          ((Imm & 0x00ff00ff00ff00ffULL) == 0);
    531 }
    532 
    533 static inline uint8_t encodeAdvSIMDModImmType6(uint64_t Imm) {
    534   return (Imm & 0xff00ULL) >> 8;
    535 }
    536 
    537 static inline uint64_t decodeAdvSIMDModImmType6(uint8_t Imm) {
    538   uint64_t EncVal = Imm;
    539   return (EncVal << 56) | (EncVal << 40) | (EncVal << 24) | (EncVal << 8);
    540 }
    541 
    542 // 0x00 0x00 abcdefgh 0xFF 0x00 0x00 abcdefgh 0xFF
    543 static inline bool isAdvSIMDModImmType7(uint64_t Imm) {
    544   return ((Imm >> 32) == (Imm & 0xffffffffULL)) &&
    545          ((Imm & 0xffff00ffffff00ffULL) == 0x000000ff000000ffULL);
    546 }
    547 
    548 static inline uint8_t encodeAdvSIMDModImmType7(uint64_t Imm) {
    549   return (Imm & 0xff00ULL) >> 8;
    550 }
    551 
    552 static inline uint64_t decodeAdvSIMDModImmType7(uint8_t Imm) {
    553   uint64_t EncVal = Imm;
    554   return (EncVal << 40) | (EncVal << 8) | 0x000000ff000000ffULL;
    555 }
    556 
    557 // 0x00 abcdefgh 0xFF 0xFF 0x00 abcdefgh 0xFF 0xFF
    558 static inline bool isAdvSIMDModImmType8(uint64_t Imm) {
    559   return ((Imm >> 32) == (Imm & 0xffffffffULL)) &&
    560          ((Imm & 0xff00ffffff00ffffULL) == 0x0000ffff0000ffffULL);
    561 }
    562 
    563 static inline uint64_t decodeAdvSIMDModImmType8(uint8_t Imm) {
    564   uint64_t EncVal = Imm;
    565   return (EncVal << 48) | (EncVal << 16) | 0x0000ffff0000ffffULL;
    566 }
    567 
    568 static inline uint8_t encodeAdvSIMDModImmType8(uint64_t Imm) {
    569   return (Imm & 0x00ff0000ULL) >> 16;
    570 }
    571 
    572 // abcdefgh abcdefgh abcdefgh abcdefgh abcdefgh abcdefgh abcdefgh abcdefgh
    573 static inline bool isAdvSIMDModImmType9(uint64_t Imm) {
    574   return ((Imm >> 32) == (Imm & 0xffffffffULL)) &&
    575          ((Imm >> 48) == (Imm & 0x0000ffffULL)) &&
    576          ((Imm >> 56) == (Imm & 0x000000ffULL));
    577 }
    578 
    579 static inline uint8_t encodeAdvSIMDModImmType9(uint64_t Imm) {
    580   return (Imm & 0xffULL);
    581 }
    582 
    583 static inline uint64_t decodeAdvSIMDModImmType9(uint8_t Imm) {
    584   uint64_t EncVal = Imm;
    585   EncVal |= (EncVal << 8);
    586   EncVal |= (EncVal << 16);
    587   EncVal |= (EncVal << 32);
    588   return EncVal;
    589 }
    590 
    591 // aaaaaaaa bbbbbbbb cccccccc dddddddd eeeeeeee ffffffff gggggggg hhhhhhhh
    592 // cmode: 1110, op: 1
    593 static inline bool isAdvSIMDModImmType10(uint64_t Imm) {
    594   uint64_t ByteA = Imm & 0xff00000000000000ULL;
    595   uint64_t ByteB = Imm & 0x00ff000000000000ULL;
    596   uint64_t ByteC = Imm & 0x0000ff0000000000ULL;
    597   uint64_t ByteD = Imm & 0x000000ff00000000ULL;
    598   uint64_t ByteE = Imm & 0x00000000ff000000ULL;
    599   uint64_t ByteF = Imm & 0x0000000000ff0000ULL;
    600   uint64_t ByteG = Imm & 0x000000000000ff00ULL;
    601   uint64_t ByteH = Imm & 0x00000000000000ffULL;
    602 
    603   return (ByteA == 0ULL || ByteA == 0xff00000000000000ULL) &&
    604          (ByteB == 0ULL || ByteB == 0x00ff000000000000ULL) &&
    605          (ByteC == 0ULL || ByteC == 0x0000ff0000000000ULL) &&
    606          (ByteD == 0ULL || ByteD == 0x000000ff00000000ULL) &&
    607          (ByteE == 0ULL || ByteE == 0x00000000ff000000ULL) &&
    608          (ByteF == 0ULL || ByteF == 0x0000000000ff0000ULL) &&
    609          (ByteG == 0ULL || ByteG == 0x000000000000ff00ULL) &&
    610          (ByteH == 0ULL || ByteH == 0x00000000000000ffULL);
    611 }
    612 
    613 static inline uint8_t encodeAdvSIMDModImmType10(uint64_t Imm) {
    614   uint8_t BitA = (Imm & 0xff00000000000000ULL) != 0;
    615   uint8_t BitB = (Imm & 0x00ff000000000000ULL) != 0;
    616   uint8_t BitC = (Imm & 0x0000ff0000000000ULL) != 0;
    617   uint8_t BitD = (Imm & 0x000000ff00000000ULL) != 0;
    618   uint8_t BitE = (Imm & 0x00000000ff000000ULL) != 0;
    619   uint8_t BitF = (Imm & 0x0000000000ff0000ULL) != 0;
    620   uint8_t BitG = (Imm & 0x000000000000ff00ULL) != 0;
    621   uint8_t BitH = (Imm & 0x00000000000000ffULL) != 0;
    622 
    623   uint8_t EncVal = BitA;
    624   EncVal <<= 1;
    625   EncVal |= BitB;
    626   EncVal <<= 1;
    627   EncVal |= BitC;
    628   EncVal <<= 1;
    629   EncVal |= BitD;
    630   EncVal <<= 1;
    631   EncVal |= BitE;
    632   EncVal <<= 1;
    633   EncVal |= BitF;
    634   EncVal <<= 1;
    635   EncVal |= BitG;
    636   EncVal <<= 1;
    637   EncVal |= BitH;
    638   return EncVal;
    639 }
    640 
    641 static inline uint64_t decodeAdvSIMDModImmType10(uint8_t Imm) {
    642   uint64_t EncVal = 0;
    643   if (Imm & 0x80) EncVal |= 0xff00000000000000ULL;
    644   if (Imm & 0x40) EncVal |= 0x00ff000000000000ULL;
    645   if (Imm & 0x20) EncVal |= 0x0000ff0000000000ULL;
    646   if (Imm & 0x10) EncVal |= 0x000000ff00000000ULL;
    647   if (Imm & 0x08) EncVal |= 0x00000000ff000000ULL;
    648   if (Imm & 0x04) EncVal |= 0x0000000000ff0000ULL;
    649   if (Imm & 0x02) EncVal |= 0x000000000000ff00ULL;
    650   if (Imm & 0x01) EncVal |= 0x00000000000000ffULL;
    651   return EncVal;
    652 }
    653 
    654 // aBbbbbbc defgh000 0x00 0x00 aBbbbbbc defgh000 0x00 0x00
    655 static inline bool isAdvSIMDModImmType11(uint64_t Imm) {
    656   uint64_t BString = (Imm & 0x7E000000ULL) >> 25;
    657   return ((Imm >> 32) == (Imm & 0xffffffffULL)) &&
    658          (BString == 0x1f || BString == 0x20) &&
    659          ((Imm & 0x0007ffff0007ffffULL) == 0);
    660 }
    661 
    662 static inline uint8_t encodeAdvSIMDModImmType11(uint64_t Imm) {
    663   uint8_t BitA = (Imm & 0x80000000ULL) != 0;
    664   uint8_t BitB = (Imm & 0x20000000ULL) != 0;
    665   uint8_t BitC = (Imm & 0x01000000ULL) != 0;
    666   uint8_t BitD = (Imm & 0x00800000ULL) != 0;
    667   uint8_t BitE = (Imm & 0x00400000ULL) != 0;
    668   uint8_t BitF = (Imm & 0x00200000ULL) != 0;
    669   uint8_t BitG = (Imm & 0x00100000ULL) != 0;
    670   uint8_t BitH = (Imm & 0x00080000ULL) != 0;
    671 
    672   uint8_t EncVal = BitA;
    673   EncVal <<= 1;
    674   EncVal |= BitB;
    675   EncVal <<= 1;
    676   EncVal |= BitC;
    677   EncVal <<= 1;
    678   EncVal |= BitD;
    679   EncVal <<= 1;
    680   EncVal |= BitE;
    681   EncVal <<= 1;
    682   EncVal |= BitF;
    683   EncVal <<= 1;
    684   EncVal |= BitG;
    685   EncVal <<= 1;
    686   EncVal |= BitH;
    687   return EncVal;
    688 }
    689 
    690 static inline uint64_t decodeAdvSIMDModImmType11(uint8_t Imm) {
    691   uint64_t EncVal = 0;
    692   if (Imm & 0x80) EncVal |= 0x80000000ULL;
    693   if (Imm & 0x40) EncVal |= 0x3e000000ULL;
    694   else            EncVal |= 0x40000000ULL;
    695   if (Imm & 0x20) EncVal |= 0x01000000ULL;
    696   if (Imm & 0x10) EncVal |= 0x00800000ULL;
    697   if (Imm & 0x08) EncVal |= 0x00400000ULL;
    698   if (Imm & 0x04) EncVal |= 0x00200000ULL;
    699   if (Imm & 0x02) EncVal |= 0x00100000ULL;
    700   if (Imm & 0x01) EncVal |= 0x00080000ULL;
    701   return (EncVal << 32) | EncVal;
    702 }
    703 
    704 // aBbbbbbb bbcdefgh 0x00 0x00 0x00 0x00 0x00 0x00
    705 static inline bool isAdvSIMDModImmType12(uint64_t Imm) {
    706   uint64_t BString = (Imm & 0x7fc0000000000000ULL) >> 54;
    707   return ((BString == 0xff || BString == 0x100) &&
    708          ((Imm & 0x0000ffffffffffffULL) == 0));
    709 }
    710 
    711 static inline uint8_t encodeAdvSIMDModImmType12(uint64_t Imm) {
    712   uint8_t BitA = (Imm & 0x8000000000000000ULL) != 0;
    713   uint8_t BitB = (Imm & 0x0040000000000000ULL) != 0;
    714   uint8_t BitC = (Imm & 0x0020000000000000ULL) != 0;
    715   uint8_t BitD = (Imm & 0x0010000000000000ULL) != 0;
    716   uint8_t BitE = (Imm & 0x0008000000000000ULL) != 0;
    717   uint8_t BitF = (Imm & 0x0004000000000000ULL) != 0;
    718   uint8_t BitG = (Imm & 0x0002000000000000ULL) != 0;
    719   uint8_t BitH = (Imm & 0x0001000000000000ULL) != 0;
    720 
    721   uint8_t EncVal = BitA;
    722   EncVal <<= 1;
    723   EncVal |= BitB;
    724   EncVal <<= 1;
    725   EncVal |= BitC;
    726   EncVal <<= 1;
    727   EncVal |= BitD;
    728   EncVal <<= 1;
    729   EncVal |= BitE;
    730   EncVal <<= 1;
    731   EncVal |= BitF;
    732   EncVal <<= 1;
    733   EncVal |= BitG;
    734   EncVal <<= 1;
    735   EncVal |= BitH;
    736   return EncVal;
    737 }
    738 
    739 static inline uint64_t decodeAdvSIMDModImmType12(uint8_t Imm) {
    740   uint64_t EncVal = 0;
    741   if (Imm & 0x80) EncVal |= 0x8000000000000000ULL;
    742   if (Imm & 0x40) EncVal |= 0x3fc0000000000000ULL;
    743   else            EncVal |= 0x4000000000000000ULL;
    744   if (Imm & 0x20) EncVal |= 0x0020000000000000ULL;
    745   if (Imm & 0x10) EncVal |= 0x0010000000000000ULL;
    746   if (Imm & 0x08) EncVal |= 0x0008000000000000ULL;
    747   if (Imm & 0x04) EncVal |= 0x0004000000000000ULL;
    748   if (Imm & 0x02) EncVal |= 0x0002000000000000ULL;
    749   if (Imm & 0x01) EncVal |= 0x0001000000000000ULL;
    750   return (EncVal << 32) | EncVal;
    751 }
    752 
    753 /// Returns true if Imm is the concatenation of a repeating pattern of type T.
    754 template <typename T>
    755 static inline bool isSVEMaskOfIdenticalElements(int64_t Imm) {
    756   auto Parts = bit_cast<std::array<T, sizeof(int64_t) / sizeof(T)>>(Imm);
    757   return all_of(Parts, [&](T Elem) { return Elem == Parts[0]; });
    758 }
    759 
    760 /// Returns true if Imm is valid for CPY/DUP.
    761 template <typename T>
    762 static inline bool isSVECpyImm(int64_t Imm) {
    763   // Imm is interpreted as a signed value, which means top bits must be all ones
    764   // (sign bits if the immediate value is negative and passed in a larger
    765   // container), or all zeroes.
    766   int64_t Mask = ~int64_t(std::numeric_limits<std::make_unsigned_t<T>>::max());
    767   if ((Imm & Mask) != 0 && (Imm & Mask) != Mask)
    768     return false;
    769 
    770   // Imm is a signed 8-bit value.
    771   // Top bits must be zeroes or sign bits.
    772   if (Imm & 0xff)
    773     return int8_t(Imm) == T(Imm);
    774 
    775   // Imm is a signed 16-bit value and multiple of 256.
    776   // Top bits must be zeroes or sign bits.
    777   if (Imm & 0xff00)
    778     return int16_t(Imm) == T(Imm);
    779 
    780   return Imm == 0;
    781 }
    782 
    783 /// Returns true if Imm is valid for ADD/SUB.
    784 template <typename T>
    785 static inline bool isSVEAddSubImm(int64_t Imm) {
    786   bool IsInt8t = std::is_same<int8_t, std::make_signed_t<T>>::value ||
    787                  std::is_same<int8_t, T>::value;
    788   return uint8_t(Imm) == Imm || (!IsInt8t && uint16_t(Imm & ~0xff) == Imm);
    789 }
    790 
    791 /// Return true if Imm is valid for DUPM and has no single CPY/DUP equivalent.
    792 static inline bool isSVEMoveMaskPreferredLogicalImmediate(int64_t Imm) {
    793   if (isSVECpyImm<int64_t>(Imm))
    794     return false;
    795 
    796   auto S = bit_cast<std::array<int32_t, 2>>(Imm);
    797   auto H = bit_cast<std::array<int16_t, 4>>(Imm);
    798   auto B = bit_cast<std::array<int8_t, 8>>(Imm);
    799 
    800   if (isSVEMaskOfIdenticalElements<int32_t>(Imm) && isSVECpyImm<int32_t>(S[0]))
    801     return false;
    802   if (isSVEMaskOfIdenticalElements<int16_t>(Imm) && isSVECpyImm<int16_t>(H[0]))
    803     return false;
    804   if (isSVEMaskOfIdenticalElements<int8_t>(Imm) && isSVECpyImm<int8_t>(B[0]))
    805     return false;
    806   return isLogicalImmediate(Imm, 64);
    807 }
    808 
    809 inline static bool isAnyMOVZMovAlias(uint64_t Value, int RegWidth) {
    810   for (int Shift = 0; Shift <= RegWidth - 16; Shift += 16)
    811     if ((Value & ~(0xffffULL << Shift)) == 0)
    812       return true;
    813 
    814   return false;
    815 }
    816 
    817 inline static bool isMOVZMovAlias(uint64_t Value, int Shift, int RegWidth) {
    818   if (RegWidth == 32)
    819     Value &= 0xffffffffULL;
    820 
    821   // "lsl #0" takes precedence: in practice this only affects "#0, lsl #0".
    822   if (Value == 0 && Shift != 0)
    823     return false;
    824 
    825   return (Value & ~(0xffffULL << Shift)) == 0;
    826 }
    827 
    828 inline static bool isMOVNMovAlias(uint64_t Value, int Shift, int RegWidth) {
    829   // MOVZ takes precedence over MOVN.
    830   if (isAnyMOVZMovAlias(Value, RegWidth))
    831     return false;
    832 
    833   Value = ~Value;
    834   if (RegWidth == 32)
    835     Value &= 0xffffffffULL;
    836 
    837   return isMOVZMovAlias(Value, Shift, RegWidth);
    838 }
    839 
    840 inline static bool isAnyMOVWMovAlias(uint64_t Value, int RegWidth) {
    841   if (isAnyMOVZMovAlias(Value, RegWidth))
    842     return true;
    843 
    844   // It's not a MOVZ, but it might be a MOVN.
    845   Value = ~Value;
    846   if (RegWidth == 32)
    847     Value &= 0xffffffffULL;
    848 
    849   return isAnyMOVZMovAlias(Value, RegWidth);
    850 }
    851 
    852 } // end namespace AArch64_AM
    853 
    854 } // end namespace llvm
    855 
    856 #endif
    857