status_w.h

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/*---------------------------------------------------------------------------+
 |  status_w.h                                                               |
 |                                                                           |
 | Copyright (C) 1992,1993                                                   |
 |                       W. Metzenthen, 22 Parker St, Ormond, Vic 3163,      |
 |                       Australia.  E-mail   [email protected]    |
 |                                                                           |
 +---------------------------------------------------------------------------*/

#ifndef _STATUS_H_
#define _STATUS_H_

#include "fpu_emu.h"        /* for definition of PECULIAR_486 */

#ifdef __ASSEMBLY__
#define Const__(x)  $##x
#else
#define Const__(x)  x
#endif

#define SW_Backward     Const__(0x8000) /* backward compatibility */
#define SW_C3       Const__(0x4000) /* condition bit 3 */
#define SW_Top      Const__(0x3800) /* top of stack */
#define SW_Top_Shift    Const__(11) /* shift for top of stack bits */
#define SW_C2       Const__(0x0400) /* condition bit 2 */
#define SW_C1       Const__(0x0200) /* condition bit 1 */
#define SW_C0       Const__(0x0100) /* condition bit 0 */
#define SW_Summary      Const__(0x0080) /* exception summary */
#define SW_Stack_Fault  Const__(0x0040) /* stack fault */
#define SW_Precision    Const__(0x0020) /* loss of precision */
#define SW_Underflow    Const__(0x0010) /* underflow */
#define SW_Overflow     Const__(0x0008) /* overflow */
#define SW_Zero_Div     Const__(0x0004) /* divide by zero */
#define SW_Denorm_Op    Const__(0x0002) /* denormalized operand */
#define SW_Invalid      Const__(0x0001) /* invalid operation */

#define SW_Exc_Mask     Const__(0x27f)  /* Status word exception bit mask */

#ifndef __ASSEMBLY__

#define COMP_A_gt_B 1
#define COMP_A_eq_B 2
#define COMP_A_lt_B 3
#define COMP_No_Comp    4
#define COMP_Denormal   0x20
#define COMP_NaN    0x40
#define COMP_SNaN   0x80

#define status_word() \
  ((partial_status & ~SW_Top & 0xffff) | ((top << SW_Top_Shift) & SW_Top))
static inline void setcc(int cc)
{
    partial_status &= ~(SW_C0 | SW_C1 | SW_C2 | SW_C3);
    partial_status |= (cc) & (SW_C0 | SW_C1 | SW_C2 | SW_C3);
}

#ifdef PECULIAR_486
   /* Default, this conveys no information, but an 80486 does it. */
   /* Clear the SW_C1 bit, "other bits undefined". */
#  define clear_C1()  { partial_status &= ~SW_C1; }
# else
#  define clear_C1()
#endif /* PECULIAR_486 */

#endif /* __ASSEMBLY__ */

#endif /* _STATUS_H_ */