i8086_dbg.h

#ifndef __I8086_DBG_H__
#define __I8086_DBG_H__

/* Base class for various arguments for instructions */
class arg
{
    public:
    virtual void dump() const =0;
};

/* Arg such as "BX" or "CL" */
class arg_reg : public arg
{
    int     m_width; // in bits (8 or 16)
    int     m_id;    // register ID
    public:
    arg_reg(int width, int reg_id) : m_width(width), m_id(reg_id) {}
    virtual void dump() const
    {
        static const char* reg_name_8[] = {"AL", "CL", "DL", "BL", "AH", "CH", "DH", "BH" };
        static const char* reg_name_16[] = {"AX", "CX", "DX", "BX", "SP", "BP", "SI", "DI" };
        fprintf(stderr, "%s", m_width==8?reg_name_8[m_id] : reg_name_16[m_id]);
    }   
};

/* Arg such as "DS" or "SS" */
class arg_sreg : public arg
{
    int     m_id;    // register ID
    public:
    arg_sreg(int reg_id) : m_id(reg_id) {}
    virtual void dump() const
    {
        static const char* segreg_name_16[] = {"ES", "CS", "SS", "DS" };
        fprintf (stderr, "%s", segreg_name_16[m_id]);
    }   
};

/* Arg such as "[mem]" */
class arg_mem : public arg
{
    int     m_width; // in bits (8 or 16)
    uint32  m_addr;  // address
    public:
    arg_mem(int width, uint32 addr) : m_width(width), m_addr(addr) {}
    virtual void dump() const
    {
        fprintf (stderr, "%s PTR [%04Xh]", m_width==8?"BYTE":"WORD", m_addr);
    }   
};

/* Arg such as [BX+SI+1234h] */
class arg_ea : public arg
{
    int m_width;
    int m_mod;
    int m_rm;
    int m_disp;
    public:
    arg_ea(int width, int mod, int rm, int disp) : m_width(width), m_mod(mod), m_rm(rm), m_disp(disp) {}
    virtual void dump() const
    {
        fprintf(stderr, "%s PTR", m_width==8?"BYTE":"WORD");
        switch ((m_mod << 3) + m_rm) { // combined mod and rm
            case  0: fprintf (stderr, "[BX+SI]"); break;
            case  1: fprintf (stderr, "[BX+DI]"); break;
            case  2: fprintf (stderr, "[BP+SI]"); break;
            case  3: fprintf (stderr, "[BP+DI]"); break;
            case  4: fprintf (stderr, "[SI]"); break;
            case  5: fprintf (stderr, "[DI]"); break;
            case  6: fprintf (stderr, "[%04Xh]", m_disp); break;
            case  7: fprintf (stderr, "[BX]"); break;

            case  8: fprintf (stderr, "[BX+SI+%04Xh]", m_disp >> 8); break;
            case  9: fprintf (stderr, "[BX+DI+%04Xh]", m_disp >> 8); break;
            case 10: fprintf (stderr, "[BP+SI+%04Xh]", m_disp >> 8); break;
            case 11: fprintf (stderr, "[BP+DI+%04Xh]", m_disp >> 8); break;
            case 12: fprintf (stderr, "[SI+%04Xh]", m_disp >> 8); break;
            case 13: fprintf (stderr, "[DI+%04Xh]", m_disp >> 8); break;
            case 14: fprintf (stderr, "[BP+%04Xh]", m_disp >> 8); break;
            case 15: fprintf (stderr, "[BX+%04Xh]", m_disp >> 8); break;

            case 16: fprintf (stderr, "[BX+SI+%04Xh]", m_disp); break;
            case 17: fprintf (stderr, "[BX+DI+%04Xh]", m_disp); break;
            case 18: fprintf (stderr, "[BP+SI+%04Xh]", m_disp); break;
            case 19: fprintf (stderr, "[BP+DI+%04Xh]", m_disp); break;
            case 20: fprintf (stderr, "[SI+%04Xh]", m_disp); break;
            case 21: fprintf (stderr, "[DI+%04Xh]", m_disp); break;
            case 22: fprintf (stderr, "[BP+%04Xh]", m_disp); break;
            case 23: fprintf (stderr, "[BX+%04Xh]", m_disp); break;
        }
    }   
};

/* Arg such as 23h or 1234h */
class arg_immed : public arg
{
    int         m_width;
    uint32      m_value;
    public:
    arg_immed(int width, uint32 value) : m_width(width), m_value(value) {}
    virtual void dump() const
    {
        fprintf (stderr, m_width==8?"%02Xh":"%04Xh", m_value);
    }   
};

#endif

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