/*
 * Copyright (c) 2010, 2012-2013, 2017-2018, 2022 Arm Limited
 * All rights reserved
 *
 * The license below extends only to copyright in the software and shall
 * not be construed as granting a license to any other intellectual
 * property including but not limited to intellectual property relating
 * to a hardware implementation of the functionality of the software
 * licensed hereunder.  You may use the software subject to the license
 * terms below provided that you ensure that this notice is replicated
 * unmodified and in its entirety in all distributions of the software,
 * modified or unmodified, in source code or in binary form.
 *
 * Copyright (c) 2007-2008 The Florida State University
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met: redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer;
 * redistributions in binary form must reproduce the above copyright
 * notice, this list of conditions and the following disclaimer in the
 * documentation and/or other materials provided with the distribution;
 * neither the name of the copyright holders nor the names of its
 * contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#ifndef __ARCH_ARM_TYPES_HH__
#define __ARCH_ARM_TYPES_HH__

#include <cstdint>

#include "arch/arm/pcstate.hh"
#include "base/bitunion.hh"
#include "base/logging.hh"

namespace gem5
{

namespace ArmISA
{
    typedef uint32_t MachInst;

    typedef uint16_t vmid_t;

    BitUnion64(ExtMachInst)
        // Decoder state
        Bitfield<63, 62> decoderFault; // See DecoderFault
        Bitfield<61> illegalExecution;
        Bitfield<60> debugStep;

        // SVE vector length, encoded in the same format as the ZCR_EL<x>.LEN
        // bitfields
        Bitfield<59, 56> sveLen;

        // ITSTATE bits
        Bitfield<55, 48> itstate;
        Bitfield<55, 52> itstateCond;
        Bitfield<51, 48> itstateMask;

        // FPSCR fields
        Bitfield<41, 40> fpscrStride;
        Bitfield<39, 37> fpscrLen;

        // Bitfields to select mode.
        Bitfield<36>     thumb;
        Bitfield<35>     bigThumb;
        Bitfield<34>     aarch64;

        // Made up bitfields that make life easier.
        Bitfield<33>     sevenAndFour;
        Bitfield<32>     isMisc;

        uint32_t         instBits;

        // All the different types of opcode fields.
        Bitfield<27, 25> encoding;
        Bitfield<25>     useImm;
        Bitfield<24, 21> opcode;
        Bitfield<24, 20> mediaOpcode;
        Bitfield<24>     opcode24;
        Bitfield<24, 23> opcode24_23;
        Bitfield<23, 20> opcode23_20;
        Bitfield<23, 21> opcode23_21;
        Bitfield<20>     opcode20;
        Bitfield<22>     opcode22;
        Bitfield<19, 16> opcode19_16;
        Bitfield<19>     opcode19;
        Bitfield<18>     opcode18;
        Bitfield<15, 12> opcode15_12;
        Bitfield<15>     opcode15;
        Bitfield<7,  4>  miscOpcode;
        Bitfield<7,5>    opc2;
        Bitfield<7>      opcode7;
        Bitfield<6>      opcode6;
        Bitfield<4>      opcode4;

        Bitfield<31, 28> condCode;
        Bitfield<20>     sField;
        Bitfield<19, 16> rn;
        Bitfield<15, 12> rd;
        Bitfield<15, 12> rt;
        Bitfield<11, 7>  shiftSize;
        Bitfield<6,  5>  shift;
        Bitfield<3,  0>  rm;

        Bitfield<11, 8>  rs;

        SubBitUnion(puswl, 24, 20)
            Bitfield<24> prepost;
            Bitfield<23> up;
            Bitfield<22> psruser;
            Bitfield<21> writeback;
            Bitfield<20> loadOp;
        EndSubBitUnion(puswl)

        Bitfield<24, 20> pubwl;

        Bitfield<7, 0> imm;

        Bitfield<11, 8>  rotate;

        Bitfield<11, 0>  immed11_0;
        Bitfield<7,  0>  immed7_0;

        Bitfield<11, 8>  immedHi11_8;
        Bitfield<3,  0>  immedLo3_0;

        Bitfield<15, 0>  regList;

        Bitfield<23, 0>  offset;

        Bitfield<23, 0>  immed23_0;

        Bitfield<11, 8>  cpNum;
        Bitfield<18, 16> fn;
        Bitfield<14, 12> fd;
        Bitfield<3>      fpRegImm;
        Bitfield<3,  0>  fm;
        Bitfield<2,  0>  fpImm;
        Bitfield<24, 20> punwl;

        Bitfield<15,  8>  m5Func;

        // 16 bit thumb bitfields
        Bitfield<15, 13> topcode15_13;
        Bitfield<13, 11> topcode13_11;
        Bitfield<12, 11> topcode12_11;
        Bitfield<12, 10> topcode12_10;
        Bitfield<11, 9>  topcode11_9;
        Bitfield<11, 8>  topcode11_8;
        Bitfield<10, 9>  topcode10_9;
        Bitfield<10, 8>  topcode10_8;
        Bitfield<9,  6>  topcode9_6;
        Bitfield<7>      topcode7;
        Bitfield<7, 6>   topcode7_6;
        Bitfield<7, 5>   topcode7_5;
        Bitfield<7, 4>   topcode7_4;
        Bitfield<3, 0>   topcode3_0;

        // 32 bit thumb bitfields
        Bitfield<28, 27> htopcode12_11;
        Bitfield<26, 25> htopcode10_9;
        Bitfield<25>     htopcode9;
        Bitfield<25, 24> htopcode9_8;
        Bitfield<25, 21> htopcode9_5;
        Bitfield<25, 20> htopcode9_4;
        Bitfield<24>     htopcode8;
        Bitfield<24, 23> htopcode8_7;
        Bitfield<24, 22> htopcode8_6;
        Bitfield<24, 21> htopcode8_5;
        Bitfield<23>     htopcode7;
        Bitfield<23, 21> htopcode7_5;
        Bitfield<22>     htopcode6;
        Bitfield<22, 21> htopcode6_5;
        Bitfield<21, 20> htopcode5_4;
        Bitfield<20>     htopcode4;

        Bitfield<19, 16> htrn;
        Bitfield<20>     hts;

        Bitfield<15>     ltopcode15;
        Bitfield<11, 8>  ltopcode11_8;
        Bitfield<7,  6>  ltopcode7_6;
        Bitfield<7,  4>  ltopcode7_4;
        Bitfield<4>      ltopcode4;

        Bitfield<11, 8>  ltrd;
        Bitfield<11, 8>  ltcoproc;
    EndBitUnion(ExtMachInst)

    BitUnion32(Affinity)
        Bitfield<31, 24> aff3;
        Bitfield<23, 16> aff2;
        Bitfield<15, 8>  aff1;
        Bitfield<7, 0>   aff0;
    EndBitUnion(Affinity)

    // Shift types for ARM instructions
    enum ArmShiftType
    {
        LSL = 0,
        LSR,
        ASR,
        ROR
    };

    // Extension types for ARM instructions
    enum ArmExtendType
    {
        UXTB = 0,
        UXTH = 1,
        UXTW = 2,
        UXTX = 3,
        SXTB = 4,
        SXTH = 5,
        SXTW = 6,
        SXTX = 7
    };

    typedef int RegContextParam;
    typedef int RegContextVal;

    //used in FP convert & round function
    enum ConvertType
    {
        SINGLE_TO_DOUBLE,
        SINGLE_TO_WORD,
        SINGLE_TO_LONG,

        DOUBLE_TO_SINGLE,
        DOUBLE_TO_WORD,
        DOUBLE_TO_LONG,

        LONG_TO_SINGLE,
        LONG_TO_DOUBLE,
        LONG_TO_WORD,
        LONG_TO_PS,

        WORD_TO_SINGLE,
        WORD_TO_DOUBLE,
        WORD_TO_LONG,
        WORD_TO_PS,

        PL_TO_SINGLE,
        PU_TO_SINGLE
    };

    //used in FP convert & round function
    enum RoundMode
    {
        RND_ZERO,
        RND_DOWN,
        RND_UP,
        RND_NEAREST
    };

    enum ExceptionLevel
    {
        EL0 = 0,
        EL1,
        EL2,
        EL3
    };

    enum OperatingMode
    {
        MODE_EL0T = 0x0,
        MODE_EL1T = 0x4,
        MODE_EL1H = 0x5,
        MODE_EL2T = 0x8,
        MODE_EL2H = 0x9,
        MODE_EL3T = 0xC,
        MODE_EL3H = 0xD,
        MODE_USER = 16,
        MODE_FIQ = 17,
        MODE_IRQ = 18,
        MODE_SVC = 19,
        MODE_MON = 22,
        MODE_ABORT = 23,
        MODE_HYP = 26,
        MODE_UNDEFINED = 27,
        MODE_SYSTEM = 31,
        MODE_MAXMODE = MODE_SYSTEM
    };

    enum ExceptionClass
    {
        EC_INVALID                 = -1,
        EC_UNKNOWN                 = 0x0,
        EC_TRAPPED_WFI_WFE         = 0x1,
        EC_TRAPPED_CP15_MCR_MRC    = 0x3,
        EC_TRAPPED_CP15_MCRR_MRRC  = 0x4,
        EC_TRAPPED_CP14_MCR_MRC    = 0x5,
        EC_TRAPPED_CP14_LDC_STC    = 0x6,
        EC_TRAPPED_HCPTR           = 0x7,
        EC_TRAPPED_SIMD_FP         = 0x7,   // AArch64 alias
        EC_TRAPPED_CP10_MRC_VMRS   = 0x8,
        EC_TRAPPED_PAC             = 0x9,
        EC_TRAPPED_BXJ             = 0xA,
        EC_TRAPPED_CP14_MCRR_MRRC  = 0xC,
        EC_ILLEGAL_INST            = 0xE,
        EC_SVC_TO_HYP              = 0x11,
        EC_SVC                     = 0x11,  // AArch64 alias
        EC_HVC                     = 0x12,
        EC_SMC_TO_HYP              = 0x13,
        EC_SMC                     = 0x13,  // AArch64 alias
        EC_SVC_64                  = 0x15,
        EC_HVC_64                  = 0x16,
        EC_SMC_64                  = 0x17,
        EC_TRAPPED_MSR_MRS_64      = 0x18,
        EC_TRAPPED_SVE             = 0x19,
        EC_PREFETCH_ABORT_TO_HYP   = 0x20,
        EC_PREFETCH_ABORT_LOWER_EL = 0x20,  // AArch64 alias
        EC_PREFETCH_ABORT_FROM_HYP = 0x21,
        EC_PREFETCH_ABORT_CURR_EL  = 0x21,  // AArch64 alias
        EC_PC_ALIGNMENT            = 0x22,
        EC_DATA_ABORT_TO_HYP       = 0x24,
        EC_DATA_ABORT_LOWER_EL     = 0x24,  // AArch64 alias
        EC_DATA_ABORT_FROM_HYP     = 0x25,
        EC_DATA_ABORT_CURR_EL      = 0x25,  // AArch64 alias
        EC_STACK_PTR_ALIGNMENT     = 0x26,
        EC_FP_EXCEPTION            = 0x28,
        EC_FP_EXCEPTION_64         = 0x2C,
        EC_SERROR                  = 0x2F,
        EC_HW_BREAKPOINT           = 0x30,
        EC_HW_BREAKPOINT_LOWER_EL  = 0x30,
        EC_HW_BREAKPOINT_CURR_EL   = 0x31,
        EC_SOFTWARE_STEP           = 0x32,
        EC_SOFTWARE_STEP_LOWER_EL  = 0x32,
        EC_SOFTWARE_STEP_CURR_EL   = 0x33,
        EC_WATCHPOINT              = 0x34,
        EC_WATCHPOINT_LOWER_EL     = 0x34,
        EC_WATCHPOINT_CURR_EL      = 0x35,
        EC_SOFTWARE_BREAKPOINT     = 0x38,
        EC_VECTOR_CATCH            = 0x3A,
        EC_SOFTWARE_BREAKPOINT_64  = 0x3C,
    };

    /**
     * Instruction decoder fault codes in ExtMachInst.
     */
    enum DecoderFault : std::uint8_t
    {
        OK = 0x0, ///< No fault
        UNALIGNED = 0x1, ///< Unaligned instruction fault

        PANIC = 0x3, ///< Internal gem5 error
    };

    BitUnion8(OperatingMode64)
        Bitfield<0> spX;
        Bitfield<3, 2> el;
        Bitfield<4> width;
    EndBitUnion(OperatingMode64)

    static bool inline
    opModeIs64(OperatingMode mode)
    {
        return ((OperatingMode64)(uint8_t)mode).width == 0;
    }

    static bool inline
    opModeIsH(OperatingMode mode)
    {
        return (mode == MODE_EL1H || mode == MODE_EL2H || mode == MODE_EL3H);
    }

    static bool inline
    opModeIsT(OperatingMode mode)
    {
        return (mode == MODE_EL0T || mode == MODE_EL1T || mode == MODE_EL2T ||
                mode == MODE_EL3T);
    }

    static ExceptionLevel inline
    opModeToEL(OperatingMode mode)
    {
        bool aarch32 = ((mode >> 4) & 1) ? true : false;
        if (aarch32) {
            switch (mode) {
              case MODE_USER:
                return EL0;
              case MODE_FIQ:
              case MODE_IRQ:
              case MODE_SVC:
              case MODE_ABORT:
              case MODE_UNDEFINED:
              case MODE_SYSTEM:
                return EL1;
              case MODE_HYP:
                return EL2;
              case MODE_MON:
                return EL3;
              default:
                panic("Invalid operating mode: %d", mode);
                break;
            }
        } else {
            // aarch64
            return (ExceptionLevel) ((mode >> 2) & 3);
        }
    }

    static inline bool
    unknownMode(OperatingMode mode)
    {
        switch (mode) {
          case MODE_EL0T:
          case MODE_EL1T:
          case MODE_EL1H:
          case MODE_EL2T:
          case MODE_EL2H:
          case MODE_EL3T:
          case MODE_EL3H:
          case MODE_USER:
          case MODE_FIQ:
          case MODE_IRQ:
          case MODE_SVC:
          case MODE_MON:
          case MODE_ABORT:
          case MODE_HYP:
          case MODE_UNDEFINED:
          case MODE_SYSTEM:
            return false;
          default:
            return true;
        }
    }

    static inline bool
    unknownMode32(OperatingMode mode)
    {
        switch (mode) {
          case MODE_USER:
          case MODE_FIQ:
          case MODE_IRQ:
          case MODE_SVC:
          case MODE_MON:
          case MODE_ABORT:
          case MODE_HYP:
          case MODE_UNDEFINED:
          case MODE_SYSTEM:
            return false;
          default:
            return true;
        }
    }

    constexpr unsigned MaxSveVecLenInBits = 2048;
    static_assert(MaxSveVecLenInBits >= 128 &&
                  MaxSveVecLenInBits <= 2048 &&
                  MaxSveVecLenInBits % 128 == 0,
                  "Unsupported max. SVE vector length");
    constexpr unsigned MaxSveVecLenInBytes  = MaxSveVecLenInBits >> 3;
    constexpr unsigned MaxSveVecLenInWords  = MaxSveVecLenInBits >> 5;
    constexpr unsigned MaxSveVecLenInDWords = MaxSveVecLenInBits >> 6;

    constexpr unsigned VecRegSizeBytes = MaxSveVecLenInBytes;
    constexpr unsigned VecPredRegSizeBits = MaxSveVecLenInBytes;

} // namespace ArmISA
} // namespace gem5

#endif