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13#include "fpu_emu.h"
14#include "fpu_system.h"
15#include "exception.h"
16
17void FPU_pop(void)
18{
19 fpu_tag_word |= 3 << ((top & 7) * 2);
20 top++;
21}
22
23int FPU_gettag0(void)
24{
25 return (fpu_tag_word >> ((top & 7) * 2)) & 3;
26}
27
28int FPU_gettagi(int stnr)
29{
30 return (fpu_tag_word >> (((top + stnr) & 7) * 2)) & 3;
31}
32
33int FPU_gettag(int regnr)
34{
35 return (fpu_tag_word >> ((regnr & 7) * 2)) & 3;
36}
37
38void FPU_settag0(int tag)
39{
40 int regnr = top;
41 regnr &= 7;
42 fpu_tag_word &= ~(3 << (regnr * 2));
43 fpu_tag_word |= (tag & 3) << (regnr * 2);
44}
45
46void FPU_settagi(int stnr, int tag)
47{
48 int regnr = stnr + top;
49 regnr &= 7;
50 fpu_tag_word &= ~(3 << (regnr * 2));
51 fpu_tag_word |= (tag & 3) << (regnr * 2);
52}
53
54void FPU_settag(int regnr, int tag)
55{
56 regnr &= 7;
57 fpu_tag_word &= ~(3 << (regnr * 2));
58 fpu_tag_word |= (tag & 3) << (regnr * 2);
59}
60
61int FPU_Special(FPU_REG const *ptr)
62{
63 int exp = exponent(ptr);
64
65 if (exp == EXP_BIAS + EXP_UNDER)
66 return TW_Denormal;
67 else if (exp != EXP_BIAS + EXP_OVER)
68 return TW_NaN;
69 else if ((ptr->sigh == 0x80000000) && (ptr->sigl == 0))
70 return TW_Infinity;
71 return TW_NaN;
72}
73
74int isNaN(FPU_REG const *ptr)
75{
76 return ((exponent(ptr) == EXP_BIAS + EXP_OVER)
77 && !((ptr->sigh == 0x80000000) && (ptr->sigl == 0)));
78}
79
80int FPU_empty_i(int stnr)
81{
82 int regnr = (top + stnr) & 7;
83
84 return ((fpu_tag_word >> (regnr * 2)) & 3) == TAG_Empty;
85}
86
87int FPU_stackoverflow(FPU_REG ** st_new_ptr)
88{
89 *st_new_ptr = &st(-1);
90
91 return ((fpu_tag_word >> (((top - 1) & 7) * 2)) & 3) != TAG_Empty;
92}
93
94void FPU_copy_to_regi(FPU_REG const *r, u_char tag, int stnr)
95{
96 reg_copy(r, &st(stnr));
97 FPU_settagi(stnr, tag);
98}
99
100void FPU_copy_to_reg1(FPU_REG const *r, u_char tag)
101{
102 reg_copy(r, &st(1));
103 FPU_settagi(1, tag);
104}
105
106void FPU_copy_to_reg0(FPU_REG const *r, u_char tag)
107{
108 int regnr = top;
109 regnr &= 7;
110
111 reg_copy(r, &st(0));
112
113 fpu_tag_word &= ~(3 << (regnr * 2));
114 fpu_tag_word |= (tag & 3) << (regnr * 2);
115}
116