1 /*---------------------------------------------------------------------------+
4 | Set FPU register tags. |
7 | W. Metzenthen, 22 Parker St, Ormond, Vic 3163, Australia |
8 | E-mail billm@jacobi.maths.monash.edu.au |
11 +---------------------------------------------------------------------------*/
14 #include "fpu_system.h"
15 #include "exception.h"
19 fpu_tag_word |= 3 << ((top & 7) * 2);
25 return (fpu_tag_word >> ((top & 7) * 2)) & 3;
28 int FPU_gettagi(int stnr)
30 return (fpu_tag_word >> (((top + stnr) & 7) * 2)) & 3;
33 int FPU_gettag(int regnr)
35 return (fpu_tag_word >> ((regnr & 7) * 2)) & 3;
38 void FPU_settag0(int tag)
42 fpu_tag_word &= ~(3 << (regnr * 2));
43 fpu_tag_word |= (tag & 3) << (regnr * 2);
46 void FPU_settagi(int stnr, int tag)
48 int regnr = stnr + top;
50 fpu_tag_word &= ~(3 << (regnr * 2));
51 fpu_tag_word |= (tag & 3) << (regnr * 2);
54 void FPU_settag(int regnr, int tag)
57 fpu_tag_word &= ~(3 << (regnr * 2));
58 fpu_tag_word |= (tag & 3) << (regnr * 2);
61 int FPU_Special(FPU_REG const *ptr)
63 int exp = exponent(ptr);
65 if (exp == EXP_BIAS + EXP_UNDER)
67 else if (exp != EXP_BIAS + EXP_OVER)
69 else if ((ptr->sigh == 0x80000000) && (ptr->sigl == 0))
74 int isNaN(FPU_REG const *ptr)
76 return ((exponent(ptr) == EXP_BIAS + EXP_OVER)
77 && !((ptr->sigh == 0x80000000) && (ptr->sigl == 0)));
80 int FPU_empty_i(int stnr)
82 int regnr = (top + stnr) & 7;
84 return ((fpu_tag_word >> (regnr * 2)) & 3) == TAG_Empty;
87 int FPU_stackoverflow(FPU_REG ** st_new_ptr)
89 *st_new_ptr = &st(-1);
91 return ((fpu_tag_word >> (((top - 1) & 7) * 2)) & 3) != TAG_Empty;
94 void FPU_copy_to_regi(FPU_REG const *r, u_char tag, int stnr)
96 reg_copy(r, &st(stnr));
97 FPU_settagi(stnr, tag);
100 void FPU_copy_to_reg1(FPU_REG const *r, u_char tag)
106 void FPU_copy_to_reg0(FPU_REG const *r, u_char tag)
113 fpu_tag_word &= ~(3 << (regnr * 2));
114 fpu_tag_word |= (tag & 3) << (regnr * 2);