kvisc/vm/pc/decode.h

// The OS/K Team licenses this file to you under the MIT license.
// See the LICENSE file in the project root for more information.

enum
{
    CD_NONE,

    CD_C, CD_O, CD_Z, CD_S, CD_P,
    CD_A, CD_AE, CD_B, CD_BE,
    CD_G, CD_GE, CD_L, CD_LE,
    CD_CXZ, COND_RES,
};

enum
{
    SUFF_LOCK = (1 << 15),
    SUFF_NOMORE = (1 << 14),
    SUFF_COND = (1 << 13),
    SUFF_REP = (1 << 15),

    Fx_MASK = 0x1F,
    F3_SHIFT = 10,
    F2_SHIFT = 5,
};

enum
{
    A_NONE      = 0b00000,
    A_REG       = 0b00001,
    A_IMM64     = 0b00010,

    AM_START    = 0b00100,

    AM_IMM64    = 0b00,
    AM_RR       = 0b01,
    AM_RRI      = 0b10,
    AM_RRII     = 0b11,

    AM_8ACC     = 0b00100,
    AM_16ACC    = 0b01000,
    AM_32ACC    = 0b01100,
    AM_64ACC    = 0b10000,

    AM_MLEN_MASK = 0b11100,
    AM_MFMT_MASK = 0b00011,
};

#define ACC_FMT_IS_MEM(x) ((x) >= AM_START && (x) <= (AM_64ACC|AM_RRII))

#define ACC_IS_MEM(x) (ACC_FMT_IS_MEM((x)->type))

struct acc_t
{
    uint type;
    ulong val;

    // A_REG
    ulong reg;

    // AM_...
    ulong addr;
    uint mlen;

    // For instruction dumping ONLY
    ushort reg1, reg2;
    short imm1, imm2;
};

enum { NOPRM, P_REG, P_IMM, P_MEM=4 };

struct instr_t
{
    char   *name;
    char   *full;

    uint    prm1;
    uint    prm2;
    uint    prm3;

    bool  (*func)(ctx_t *, acc_t *, acc_t *, acc_t *,
                           ulong *, ulong *, ulong *);
};

bool eval_cond(ctx_t *ctx, uint cond);

void exec_instr(ctx_t *ctx,
                instr_t *in,
                acc_t *p1,
                acc_t *p2,
                acc_t *p3,
                bool lock,
                bool rep);

void extract_param(ctx_t *ctx,
                   acc_t *p,
                   uchar fmt);

void dump_instr(ctx_t *ctx,
                instr_t *in,
                acc_t *p1,
                acc_t *p2,
                acc_t *p3,
                bool lock,
                bool rep);