arch/i386/math-emu/status_w.h

   1 /*---------------------------------------------------------------------------+
   2  |  status_w.h                                                               |
   3  |                                                                           |
   4  | Copyright (C) 1992,1993                                                   |
   5  |                       W. Metzenthen, 22 Parker St, Ormond, Vic 3163,      |
   6  |                       Australia.  E-mail   billm@vaxc.cc.monash.edu.au    |
   7  |                                                                           |
   8  +---------------------------------------------------------------------------*/
   9
  10 #ifndef _STATUS_H_
  11 #define _STATUS_H_
  12
  13 #include "fpu_emu.h"    /* for definition of PECULIAR_486 */
  14
  15 #ifdef __ASSEMBLY__
  16 #define Const__(x)      $##x
  17 #else
  18 #define Const__(x)      x
  19 #endif
  20
  21 #define SW_Backward     Const__(0x8000) /* backward compatibility */
  22 #define SW_C3           Const__(0x4000) /* condition bit 3 */
  23 #define SW_Top          Const__(0x3800) /* top of stack */
  24 #define SW_Top_Shift    Const__(11)     /* shift for top of stack bits */
  25 #define SW_C2           Const__(0x0400) /* condition bit 2 */
  26 #define SW_C1           Const__(0x0200) /* condition bit 1 */
  27 #define SW_C0           Const__(0x0100) /* condition bit 0 */
  28 #define SW_Summary      Const__(0x0080) /* exception summary */
  29 #define SW_Stack_Fault  Const__(0x0040) /* stack fault */
  30 #define SW_Precision    Const__(0x0020) /* loss of precision */
  31 #define SW_Underflow    Const__(0x0010) /* underflow */
  32 #define SW_Overflow     Const__(0x0008) /* overflow */
  33 #define SW_Zero_Div     Const__(0x0004) /* divide by zero */
  34 #define SW_Denorm_Op    Const__(0x0002) /* denormalized operand */
  35 #define SW_Invalid      Const__(0x0001) /* invalid operation */
  36
  37 #define SW_Exc_Mask     Const__(0x27f)  /* Status word exception bit mask */
  38
  39 #ifndef __ASSEMBLY__
  40
  41 #define COMP_A_gt_B     1
  42 #define COMP_A_eq_B     2
  43 #define COMP_A_lt_B     3
  44 #define COMP_No_Comp    4
  45 #define COMP_Denormal   0x20
  46 #define COMP_NaN        0x40
  47 #define COMP_SNaN       0x80
  48
  49 #define status_word() \
  50   ((partial_status & ~SW_Top & 0xffff) | ((top << SW_Top_Shift) & SW_Top))
  51 static inline void setcc(int cc)
  52 {
  53         partial_status &= ~(SW_C0|SW_C1|SW_C2|SW_C3);
  54         partial_status |= (cc) & (SW_C0|SW_C1|SW_C2|SW_C3);
  55 }
  56
  57 #ifdef PECULIAR_486
  58    /* Default, this conveys no information, but an 80486 does it. */
  59    /* Clear the SW_C1 bit, "other bits undefined". */
  60 #  define clear_C1()  { partial_status &= ~SW_C1; }
  61 # else
  62 #  define clear_C1()
  63 #endif /* PECULIAR_486 */
  64
  65 #endif /* __ASSEMBLY__ */
  66
  67 #endif /* _STATUS_H_ */