/*
DingusPPC - The Experimental PowerPC Macintosh emulator
Copyright (C) 2018-21 divingkatae and maximum
                      (theweirdo)     spatium

(Contact divingkatae#1017 or powermax#2286 on Discord for more info)

This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program.  If not, see <https://www.gnu.org/licenses/>.
*/

#ifndef PPCEMU_H
#define PPCEMU_H

#include <devices/memctrl/memctrlbase.h>
#include <endianswap.h>

#include <cinttypes>
#include <functional>
#include <setjmp.h>
#include <string>

// Uncomment this to help debug the emulator further
//#define EXHAUSTIVE_DEBUG 1

// Uncomment this to have a more graceful approach to illegal opcodes
//#define ILLEGAL_OP_SAFE 1

// Uncomment this to use GCC built-in functions.
#define USE_GCC_BUILTINS 1

// Uncomment this to use Visual Studio built-in functions.
//#define USE_VS_BUILTINS 1

//#define CPU_PROFILING // enable CPU profiling

enum endian_switch { big_end = 0, little_end = 1 };

typedef void (*PPCOpcode)(void);

union FPR_storage {
    double dbl64_r;      // double floating-point representation
    uint64_t int64_r;    // double integer representation
};

/**
Except for the floating-point registers, all registers require
32 bits for representation. Floating-point registers need 64 bits.

  gpr = General Purpose Register
  fpr = Floating Point (FP) Register
   cr = Condition Register
  tbr = Time Base Register
fpscr = FP Status and Condition Register
  spr = Special Register
  msr = Machine State Register
   sr = Segment Register
**/

typedef struct struct_ppc_state {
    FPR_storage fpr[32];
    uint32_t pc;    // Referred as the CIA in the PPC manual
    uint32_t gpr[32];
    uint32_t cr;
    uint32_t fpscr;
    uint32_t tbr[2];
    uint32_t spr[1024];
    uint32_t msr;
    uint32_t sr[16];
    bool reserve;    // reserve bit used for lwarx and stcwx
} SetPRS;

extern SetPRS ppc_state;

/** symbolic names for frequently used SPRs */
enum SPR : int {
    MQ    = 0,
    XER   = 1,
    LR    = 8,
    CTR   = 9,
    DSISR = 18,
    DAR   = 19,
    DEC   = 22,
    SDR1  = 25,
    SRR0  = 26,
    SRR1  = 27,
    PVR   = 287
};

/** symbolic names for frequently used SPRs */
enum TBR : int { TBL = 0, TBU = 1 };

/** symbolic names for common PPC processors */
enum PPC_VER : uint32_t {
    MPC601  = 0x00010001,
    MPC603  = 0x00030001,
    MPC604  = 0x00040001,
    MPC603E = 0x00060101,
    MPC750  = 0x00080200
};

/**
typedef struct struct_ppc64_state {
    FPR_storage fpr [32];
    uint64_t pc; //Referred as the CIA in the PPC manual
    uint64_t gpr [32];
    uint32_t cr;
    uint32_t fpscr;
    uint32_t tbr [2];
    uint64_t spr [1024];
    uint32_t msr;
    uint32_t sr [16];
    bool reserve; //reserve bit used for lwarx and stcwx
} SetPRS64;

extern SetPRS64 ppc_state64;
**/

/**
Specific SPRS to be weary of:

USER MODEL
SPR 1 - XER
SPR 8 - Link Register / Branch
  b0 - Summary Overflow
  b1 - Overflow
  b2 - Carry
  b25-31 - Number of bytes to transfer
SPR 9 - Count

SUPERVISOR MODEL
19 is the Data Address Register
22 is the Decrementer
26, 27 are the Save and Restore Registers (SRR0, SRR1)
272 - 275 are the SPRGs
284 - 285 for writing to the TBR's.
528 - 535 are the Instruction BAT registers
536 - 543 are the Data BAT registers
**/

extern uint32_t opcode_value;      // used for interpreting opcodes

extern uint64_t timebase_counter;
extern uint64_t tbr_wr_timestamp;
extern uint64_t tbr_wr_value;
extern uint64_t tbr_freq_hz;

// Additional steps to prevent overflow?
extern int32_t add_result;
extern int32_t simult_result;
extern uint32_t uiadd_result;
extern uint32_t uimult_result;

extern uint32_t crf_d;
extern uint32_t crf_s;
extern uint32_t reg_s;
extern uint32_t reg_d;
extern uint32_t reg_a;
extern uint32_t reg_b;
extern uint32_t reg_c;
extern uint32_t xercon;
extern uint32_t cmp_c;
extern uint32_t crm;
extern uint32_t br_bo;
extern uint32_t br_bi;
extern uint32_t rot_sh;
extern uint32_t rot_mb;
extern uint32_t rot_me;
extern uint32_t uimm;
extern uint32_t grab_sr;
extern uint32_t grab_inb;    // This is for grabbing the number of immediate bytes for loading and storing
extern uint32_t ppc_to;
extern int32_t simm;
extern int32_t adr_li;
extern int32_t br_bd;

// Used for GP calcs
extern uint32_t ppc_result_a;
extern uint32_t ppc_result_b;
extern uint32_t ppc_result_c;
extern uint32_t ppc_result_d;

// Used for FP calcs
extern uint64_t ppc_result64_a;
extern uint64_t ppc_result64_b;
extern uint64_t ppc_result64_c;
extern uint64_t ppc_result64_d;

/* Flags for controlling interpreter execution. */
enum {
    EXEF_BRANCH    = 1 << 0,
    EXEF_EXCEPTION = 1 << 1,
    EXEF_RFI       = 1 << 2,
    EXEF_TIMER     = 1 << 7
};

enum CR_select : int32_t {
    CR0_field = (0xF << 28),
    CR1_field = (0xF << 24),
};

enum CRx_bit : uint32_t {
    CR_SO = 28,
    CR_EQ = 29,
    CR_GT = 30,
    CR_LT = 31 };

enum CR1_bit : uint32_t {
    CR1_OX = 24,
    CR1_VX,
    CR1_FEX,
    CR1_FX,
};

enum FPSCR : uint32_t {
    RN = 0x3,
    NI = 0x4,
    XE = 0x8,
    ZE = 0x10,
    UE = 0x20,
    OE = 0x40,
    VE = 0x80,
    VXCVI = 0x100,
    VXSQRT = 0x200,
    VXSOFT = 0x400,
    FPRF   = 0x1F000,
    FPCC_FUNAN = 0x10000,
    FPCC_NEG   = 0x8000,
    FPCC_POS   = 0x4000,
    FPCC_ZERO  = 0x2000,
    FPCC_FPRCD = 0x1000,
    FI         = 0x20000,
    FR         = 0x40000,
    VXVC       = 0x80000,
    VXIMZ      = 0x100000,
    VXZDZ      = 0x200000,
    VXIDI      = 0x400000,
    VXISI      = 0x800000,
    VXSNAN     = 0x1000000,
    XX         = 0x2000000,
    ZX         = 0x4000000,
    UX         = 0x8000000,
    OX         = 0x10000000,
    VX         = 0x20000000,
    FEX        = 0x40000000,
    FX         = 0x80000000
};

//for inf and nan checks
enum FPOP : int {
    DIV  = 0x12,
    SUB  = 0x14,
    ADD  = 0x15,
    MUL   = 0x19,
    FMSUB = 0x1C,
    FMADD = 0x1D,
    FNMSUB = 0x1E,
    FNMADD = 0x1F,
};

/** PowerPC exception types. */
enum class Except_Type {
    EXC_SYSTEM_RESET = 1,
    EXC_MACHINE_CHECK,
    EXC_DSI,
    EXC_ISI,
    EXC_EXT_INT,
    EXC_ALIGNMENT,
    EXC_PROGRAM,
    EXC_NO_FPU,
    EXC_DECR,
    EXC_SYSCALL = 12,
    EXC_TRACE   = 13
};

/** Programm Exception subclasses. */
enum Exc_Cause : uint32_t {
    FPU_OFF     = 1 << (31 - 11),
    ILLEGAL_OP  = 1 << (31 - 12),
    NOT_ALLOWED = 1 << (31 - 13),
    TRAP        = 1 << (31 - 14),
};

extern unsigned exec_flags;

extern jmp_buf exc_env;

extern bool grab_return;

extern bool power_on;

extern bool is_601;        // For PowerPC 601 Emulation
extern bool is_altivec;    // For Altivec Emulation
extern bool is_64bit;      // For PowerPC G5 Emulation

extern bool rc_flag;    // Record flag
extern bool oe_flag;    // Overflow flag

// Important Addressing Integers
extern uint32_t ppc_cur_instruction;
extern uint32_t ppc_effective_address;
extern uint32_t ppc_next_instruction_address;

// Profiling Stats
#ifdef CPU_PROFILING
extern uint64_t num_executed_instrs;
extern uint64_t num_supervisor_instrs;
extern uint64_t num_int_loads;
extern uint64_t num_int_stores;
extern uint64_t exceptions_processed;
#endif

// Function prototypes
extern void ppc_cpu_init(MemCtrlBase* mem_ctrl, uint32_t cpu_version);
extern void ppc_mmu_init(uint32_t cpu_version);

void ppc_illegalop();
void ppc_fpu_off();
void ppc_ext_int();

//void ppc_opcode4();
void ppc_opcode16();
void ppc_opcode18();
void ppc_opcode19();
void ppc_opcode31();
void ppc_opcode59();
void ppc_opcode63();

void initialize_ppc_opcode_tables();

extern double fp_return_double(uint32_t reg);
extern uint64_t fp_return_uint64(uint32_t reg);

extern void ppc_grab_regsda();
extern void ppc_grab_regsdb();

extern void ppc_grab_regssa();
extern void ppc_grab_regssb();

extern void ppc_grab_regsdab();
extern void ppc_grab_regssab();

extern void ppc_grab_regsdasimm();
extern void ppc_grab_regsdauimm();
extern void ppc_grab_regsasimm();
extern void ppc_grab_regssauimm();

extern void ppc_store_result_regd();
extern void ppc_store_result_rega();

void ppc_changecrf0(uint32_t set_result);
void ppc_fp_changecrf1();

/* Exception handlers. */
void ppc_exception_handler(Except_Type exception_type, uint32_t srr1_bits);
[[noreturn]] void dbg_exception_handler(Except_Type exception_type, uint32_t srr1_bits);

// MEMORY DECLARATIONS
extern MemCtrlBase* mem_ctrl_instance;

extern void add_ctx_sync_action(const std::function<void()> &);
extern void do_ctx_sync(void);

// The functions used by the PowerPC processor
namespace dppc_interpreter {
extern void ppc_bcctr();
extern void ppc_bcctrl();
extern void ppc_bclr();
extern void ppc_bclrl();
extern void ppc_crand();
extern void ppc_crandc();
extern void ppc_creqv();
extern void ppc_crnand();
extern void ppc_crnor();
extern void ppc_cror();
extern void ppc_crorc();
extern void ppc_crxor();
extern void ppc_isync();

extern void ppc_add();
extern void ppc_addc();
extern void ppc_adde();
extern void ppc_addme();
extern void ppc_addze();
extern void ppc_and();
extern void ppc_andc();
extern void ppc_cmp();
extern void ppc_cmpl();
extern void ppc_cntlzw();
extern void ppc_dcbf();
extern void ppc_dcbi();
extern void ppc_dcbst();
extern void ppc_dcbt();
extern void ppc_dcbtst();
extern void ppc_dcbz();
extern void ppc_divw();
extern void ppc_divwu();
extern void ppc_eciwx();
extern void ppc_ecowx();
extern void ppc_eieio();
extern void ppc_eqv();
extern void ppc_extsb();
extern void ppc_extsh();
extern void ppc_icbi();
extern void ppc_mftb();
extern void ppc_lhzux();
extern void ppc_lhzx();
extern void ppc_lhaux();
extern void ppc_lhax();
extern void ppc_lhbrx();
extern void ppc_lwarx();
extern void ppc_lbzux();
extern void ppc_lbzx();
extern void ppc_lwbrx();
extern void ppc_lwzux();
extern void ppc_lwzx();
extern void ppc_mcrxr();
extern void ppc_mfcr();
extern void ppc_mulhwu();
extern void ppc_mulhw();
extern void ppc_mullw();
extern void ppc_nand();
extern void ppc_neg();
extern void ppc_nor();
extern void ppc_or();
extern void ppc_orc();
extern void ppc_slw();
extern void ppc_srw();
extern void ppc_sraw();
extern void ppc_srawi();
extern void ppc_stbx();
extern void ppc_stbux();
extern void ppc_stfiwx();
extern void ppc_sthx();
extern void ppc_sthux();
extern void ppc_sthbrx();
extern void ppc_stwx();
extern void ppc_stwcx();
extern void ppc_stwux();
extern void ppc_stwbrx();
extern void ppc_subf();
extern void ppc_subfc();
extern void ppc_subfe();
extern void ppc_subfme();
extern void ppc_subfze();
extern void ppc_sync();
extern void ppc_tlbia();
extern void ppc_tlbie();
extern void ppc_tlbli();
extern void ppc_tlbld();
extern void ppc_tlbsync();
extern void ppc_tw();
extern void ppc_xor();

extern void ppc_lswi();
extern void ppc_lswx();
extern void ppc_stswi();
extern void ppc_stswx();

extern void ppc_mfsr();
extern void ppc_mfsrin();
extern void ppc_mtsr();
extern void ppc_mtsrin();

extern void ppc_mcrf();
extern void ppc_mtcrf();
extern void ppc_mfmsr();
extern void ppc_mfspr();
extern void ppc_mtmsr();
extern void ppc_mtspr();

extern void ppc_mtfsb0();
extern void ppc_mtfsb1();
extern void ppc_mcrfs();
extern void ppc_fmr();
extern void ppc_mffs();
extern void ppc_mtfsf();
extern void ppc_mtfsfi();

extern void ppc_addi();
extern void ppc_addic();
extern void ppc_addicdot();
extern void ppc_addis();
extern void ppc_andidot();
extern void ppc_andisdot();
extern void ppc_b();
extern void ppc_ba();
extern void ppc_bl();
extern void ppc_bla();
extern void ppc_bc();
extern void ppc_bca();
extern void ppc_bcl();
extern void ppc_bcla();
extern void ppc_cmpi();
extern void ppc_cmpli();
extern void ppc_lbz();
extern void ppc_lbzu();
extern void ppc_lha();
extern void ppc_lhau();
extern void ppc_lhz();
extern void ppc_lhzu();
extern void ppc_lwz();
extern void ppc_lwzu();
extern void ppc_lmw();
extern void ppc_mulli();
extern void ppc_ori();
extern void ppc_oris();
extern void ppc_rfi();
extern void ppc_rlwimi();
extern void ppc_rlwinm();
extern void ppc_rlwnm();
extern void ppc_sc();
extern void ppc_stb();
extern void ppc_stbu();
extern void ppc_sth();
extern void ppc_sthu();
extern void ppc_stw();
extern void ppc_stwu();
extern void ppc_stmw();
extern void ppc_subfic();
extern void ppc_twi();
extern void ppc_xori();
extern void ppc_xoris();

extern void ppc_lfs();
extern void ppc_lfsu();
extern void ppc_lfsx();
extern void ppc_lfsux();
extern void ppc_lfd();
extern void ppc_lfdu();
extern void ppc_lfdx();
extern void ppc_lfdux();
extern void ppc_stfs();
extern void ppc_stfsu();
extern void ppc_stfsx();
extern void ppc_stfsux();
extern void ppc_stfd();
extern void ppc_stfdu();
extern void ppc_stfdx();
extern void ppc_stfdux();

extern void ppc_fadd();
extern void ppc_fsub();
extern void ppc_fmul();
extern void ppc_fdiv();
extern void ppc_fadds();
extern void ppc_fsubs();
extern void ppc_fmuls();
extern void ppc_fdivs();
extern void ppc_fmadd();
extern void ppc_fmsub();
extern void ppc_fnmadd();
extern void ppc_fnmsub();
extern void ppc_fmadds();
extern void ppc_fmsubs();
extern void ppc_fnmadds();
extern void ppc_fnmsubs();
extern void ppc_fabs();
extern void ppc_fnabs();
extern void ppc_fneg();
extern void ppc_fsel();
extern void ppc_fres();
extern void ppc_fsqrts();
extern void ppc_fsqrt();
extern void ppc_frsqrte();
extern void ppc_frsp();
extern void ppc_fctiw();
extern void ppc_fctiwz();

extern void ppc_fcmpo();
extern void ppc_fcmpu();

// Power-specific instructions
extern void power_abs();
extern void power_clcs();
extern void power_div();
extern void power_divs();
extern void power_doz();
extern void power_dozi();
extern void power_lscbx();
extern void power_maskg();
extern void power_maskir();
extern void power_mul();
extern void power_nabs();
extern void power_rlmi();
extern void power_rrib();
extern void power_sle();
extern void power_sleq();
extern void power_sliq();
extern void power_slliq();
extern void power_sllq();
extern void power_slq();
extern void power_sraiq();
extern void power_sraq();
extern void power_sre();
extern void power_srea();
extern void power_sreq();
extern void power_sriq();
extern void power_srliq();
extern void power_srlq();
extern void power_srq();
}    // namespace dppc_interpreter

// AltiVec instructions

// 64-bit instructions

// G5+ instructions

extern uint64_t get_virt_time_ns(void);

extern void ppc_main_opcode(void);
extern void ppc_exec(void);
extern void ppc_exec_single(void);
extern void ppc_exec_until(uint32_t goal_addr);
extern void ppc_exec_dbg(uint32_t start_addr, uint32_t size);

/* debugging support API */
void print_fprs(void);                   /* print content of the floating-point registers  */
uint64_t get_reg(std::string reg_name); /* get content of the register reg_name */
void set_reg(std::string reg_name, uint64_t val); /* set reg_name to val */

#endif /* PPCEMU_H */