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Diffstat (limited to 'arch/i386/math-emu/fpu_aux.c')
-rw-r--r-- | arch/i386/math-emu/fpu_aux.c | 204 |
1 files changed, 204 insertions, 0 deletions
diff --git a/arch/i386/math-emu/fpu_aux.c b/arch/i386/math-emu/fpu_aux.c new file mode 100644 index 000000000000..20886cfb9f76 --- /dev/null +++ b/arch/i386/math-emu/fpu_aux.c | |||
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1 | /*---------------------------------------------------------------------------+ | ||
2 | | fpu_aux.c | | ||
3 | | | | ||
4 | | Code to implement some of the FPU auxiliary instructions. | | ||
5 | | | | ||
6 | | Copyright (C) 1992,1993,1994,1997 | | ||
7 | | W. Metzenthen, 22 Parker St, Ormond, Vic 3163, Australia | | ||
8 | | E-mail billm@suburbia.net | | ||
9 | | | | ||
10 | | | | ||
11 | +---------------------------------------------------------------------------*/ | ||
12 | |||
13 | #include "fpu_system.h" | ||
14 | #include "exception.h" | ||
15 | #include "fpu_emu.h" | ||
16 | #include "status_w.h" | ||
17 | #include "control_w.h" | ||
18 | |||
19 | |||
20 | static void fnop(void) | ||
21 | { | ||
22 | } | ||
23 | |||
24 | static void fclex(void) | ||
25 | { | ||
26 | partial_status &= ~(SW_Backward|SW_Summary|SW_Stack_Fault|SW_Precision| | ||
27 | SW_Underflow|SW_Overflow|SW_Zero_Div|SW_Denorm_Op| | ||
28 | SW_Invalid); | ||
29 | no_ip_update = 1; | ||
30 | } | ||
31 | |||
32 | /* Needs to be externally visible */ | ||
33 | void finit(void) | ||
34 | { | ||
35 | control_word = 0x037f; | ||
36 | partial_status = 0; | ||
37 | top = 0; /* We don't keep top in the status word internally. */ | ||
38 | fpu_tag_word = 0xffff; | ||
39 | /* The behaviour is different from that detailed in | ||
40 | Section 15.1.6 of the Intel manual */ | ||
41 | operand_address.offset = 0; | ||
42 | operand_address.selector = 0; | ||
43 | instruction_address.offset = 0; | ||
44 | instruction_address.selector = 0; | ||
45 | instruction_address.opcode = 0; | ||
46 | no_ip_update = 1; | ||
47 | } | ||
48 | |||
49 | /* | ||
50 | * These are nops on the i387.. | ||
51 | */ | ||
52 | #define feni fnop | ||
53 | #define fdisi fnop | ||
54 | #define fsetpm fnop | ||
55 | |||
56 | static FUNC const finit_table[] = { | ||
57 | feni, fdisi, fclex, finit, | ||
58 | fsetpm, FPU_illegal, FPU_illegal, FPU_illegal | ||
59 | }; | ||
60 | |||
61 | void finit_(void) | ||
62 | { | ||
63 | (finit_table[FPU_rm])(); | ||
64 | } | ||
65 | |||
66 | |||
67 | static void fstsw_ax(void) | ||
68 | { | ||
69 | *(short *) &FPU_EAX = status_word(); | ||
70 | no_ip_update = 1; | ||
71 | } | ||
72 | |||
73 | static FUNC const fstsw_table[] = { | ||
74 | fstsw_ax, FPU_illegal, FPU_illegal, FPU_illegal, | ||
75 | FPU_illegal, FPU_illegal, FPU_illegal, FPU_illegal | ||
76 | }; | ||
77 | |||
78 | void fstsw_(void) | ||
79 | { | ||
80 | (fstsw_table[FPU_rm])(); | ||
81 | } | ||
82 | |||
83 | |||
84 | static FUNC const fp_nop_table[] = { | ||
85 | fnop, FPU_illegal, FPU_illegal, FPU_illegal, | ||
86 | FPU_illegal, FPU_illegal, FPU_illegal, FPU_illegal | ||
87 | }; | ||
88 | |||
89 | void fp_nop(void) | ||
90 | { | ||
91 | (fp_nop_table[FPU_rm])(); | ||
92 | } | ||
93 | |||
94 | |||
95 | void fld_i_(void) | ||
96 | { | ||
97 | FPU_REG *st_new_ptr; | ||
98 | int i; | ||
99 | u_char tag; | ||
100 | |||
101 | if ( STACK_OVERFLOW ) | ||
102 | { FPU_stack_overflow(); return; } | ||
103 | |||
104 | /* fld st(i) */ | ||
105 | i = FPU_rm; | ||
106 | if ( NOT_EMPTY(i) ) | ||
107 | { | ||
108 | reg_copy(&st(i), st_new_ptr); | ||
109 | tag = FPU_gettagi(i); | ||
110 | push(); | ||
111 | FPU_settag0(tag); | ||
112 | } | ||
113 | else | ||
114 | { | ||
115 | if ( control_word & CW_Invalid ) | ||
116 | { | ||
117 | /* The masked response */ | ||
118 | FPU_stack_underflow(); | ||
119 | } | ||
120 | else | ||
121 | EXCEPTION(EX_StackUnder); | ||
122 | } | ||
123 | |||
124 | } | ||
125 | |||
126 | |||
127 | void fxch_i(void) | ||
128 | { | ||
129 | /* fxch st(i) */ | ||
130 | FPU_REG t; | ||
131 | int i = FPU_rm; | ||
132 | FPU_REG *st0_ptr = &st(0), *sti_ptr = &st(i); | ||
133 | long tag_word = fpu_tag_word; | ||
134 | int regnr = top & 7, regnri = ((regnr + i) & 7); | ||
135 | u_char st0_tag = (tag_word >> (regnr*2)) & 3; | ||
136 | u_char sti_tag = (tag_word >> (regnri*2)) & 3; | ||
137 | |||
138 | if ( st0_tag == TAG_Empty ) | ||
139 | { | ||
140 | if ( sti_tag == TAG_Empty ) | ||
141 | { | ||
142 | FPU_stack_underflow(); | ||
143 | FPU_stack_underflow_i(i); | ||
144 | return; | ||
145 | } | ||
146 | if ( control_word & CW_Invalid ) | ||
147 | { | ||
148 | /* Masked response */ | ||
149 | FPU_copy_to_reg0(sti_ptr, sti_tag); | ||
150 | } | ||
151 | FPU_stack_underflow_i(i); | ||
152 | return; | ||
153 | } | ||
154 | if ( sti_tag == TAG_Empty ) | ||
155 | { | ||
156 | if ( control_word & CW_Invalid ) | ||
157 | { | ||
158 | /* Masked response */ | ||
159 | FPU_copy_to_regi(st0_ptr, st0_tag, i); | ||
160 | } | ||
161 | FPU_stack_underflow(); | ||
162 | return; | ||
163 | } | ||
164 | clear_C1(); | ||
165 | |||
166 | reg_copy(st0_ptr, &t); | ||
167 | reg_copy(sti_ptr, st0_ptr); | ||
168 | reg_copy(&t, sti_ptr); | ||
169 | |||
170 | tag_word &= ~(3 << (regnr*2)) & ~(3 << (regnri*2)); | ||
171 | tag_word |= (sti_tag << (regnr*2)) | (st0_tag << (regnri*2)); | ||
172 | fpu_tag_word = tag_word; | ||
173 | } | ||
174 | |||
175 | |||
176 | void ffree_(void) | ||
177 | { | ||
178 | /* ffree st(i) */ | ||
179 | FPU_settagi(FPU_rm, TAG_Empty); | ||
180 | } | ||
181 | |||
182 | |||
183 | void ffreep(void) | ||
184 | { | ||
185 | /* ffree st(i) + pop - unofficial code */ | ||
186 | FPU_settagi(FPU_rm, TAG_Empty); | ||
187 | FPU_pop(); | ||
188 | } | ||
189 | |||
190 | |||
191 | void fst_i_(void) | ||
192 | { | ||
193 | /* fst st(i) */ | ||
194 | FPU_copy_to_regi(&st(0), FPU_gettag0(), FPU_rm); | ||
195 | } | ||
196 | |||
197 | |||
198 | void fstp_i(void) | ||
199 | { | ||
200 | /* fstp st(i) */ | ||
201 | FPU_copy_to_regi(&st(0), FPU_gettag0(), FPU_rm); | ||
202 | FPU_pop(); | ||
203 | } | ||
204 | |||