vmsvga: don't process more than 1024 fifo commands at once
[qemu.git] / target-i386 / cc_helper_template.h
1 /*
2 * x86 condition code helpers
3 *
4 * Copyright (c) 2008 Fabrice Bellard
5 *
6 * This library is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2 of the License, or (at your option) any later version.
10 *
11 * This library is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
15 *
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with this library; if not, see <http://www.gnu.org/licenses/>.
18 */
19
20 #define DATA_BITS (1 << (3 + SHIFT))
21
22 #if DATA_BITS == 8
23 #define SUFFIX b
24 #define DATA_TYPE uint8_t
25 #elif DATA_BITS == 16
26 #define SUFFIX w
27 #define DATA_TYPE uint16_t
28 #elif DATA_BITS == 32
29 #define SUFFIX l
30 #define DATA_TYPE uint32_t
31 #elif DATA_BITS == 64
32 #define SUFFIX q
33 #define DATA_TYPE uint64_t
34 #else
35 #error unhandled operand size
36 #endif
37
38 #define SIGN_MASK (((DATA_TYPE)1) << (DATA_BITS - 1))
39
40 /* dynamic flags computation */
41
42 static int glue(compute_all_add, SUFFIX)(DATA_TYPE dst, DATA_TYPE src1)
43 {
44 int cf, pf, af, zf, sf, of;
45 DATA_TYPE src2 = dst - src1;
46
47 cf = dst < src1;
48 pf = parity_table[(uint8_t)dst];
49 af = (dst ^ src1 ^ src2) & CC_A;
50 zf = (dst == 0) * CC_Z;
51 sf = lshift(dst, 8 - DATA_BITS) & CC_S;
52 of = lshift((src1 ^ src2 ^ -1) & (src1 ^ dst), 12 - DATA_BITS) & CC_O;
53 return cf | pf | af | zf | sf | of;
54 }
55
56 static int glue(compute_c_add, SUFFIX)(DATA_TYPE dst, DATA_TYPE src1)
57 {
58 return dst < src1;
59 }
60
61 static int glue(compute_all_adc, SUFFIX)(DATA_TYPE dst, DATA_TYPE src1,
62 DATA_TYPE src3)
63 {
64 int cf, pf, af, zf, sf, of;
65 DATA_TYPE src2 = dst - src1 - src3;
66
67 cf = (src3 ? dst <= src1 : dst < src1);
68 pf = parity_table[(uint8_t)dst];
69 af = (dst ^ src1 ^ src2) & 0x10;
70 zf = (dst == 0) << 6;
71 sf = lshift(dst, 8 - DATA_BITS) & 0x80;
72 of = lshift((src1 ^ src2 ^ -1) & (src1 ^ dst), 12 - DATA_BITS) & CC_O;
73 return cf | pf | af | zf | sf | of;
74 }
75
76 static int glue(compute_c_adc, SUFFIX)(DATA_TYPE dst, DATA_TYPE src1,
77 DATA_TYPE src3)
78 {
79 return src3 ? dst <= src1 : dst < src1;
80 }
81
82 static int glue(compute_all_sub, SUFFIX)(DATA_TYPE dst, DATA_TYPE src2)
83 {
84 int cf, pf, af, zf, sf, of;
85 DATA_TYPE src1 = dst + src2;
86
87 cf = src1 < src2;
88 pf = parity_table[(uint8_t)dst];
89 af = (dst ^ src1 ^ src2) & CC_A;
90 zf = (dst == 0) * CC_Z;
91 sf = lshift(dst, 8 - DATA_BITS) & CC_S;
92 of = lshift((src1 ^ src2) & (src1 ^ dst), 12 - DATA_BITS) & CC_O;
93 return cf | pf | af | zf | sf | of;
94 }
95
96 static int glue(compute_c_sub, SUFFIX)(DATA_TYPE dst, DATA_TYPE src2)
97 {
98 DATA_TYPE src1 = dst + src2;
99
100 return src1 < src2;
101 }
102
103 static int glue(compute_all_sbb, SUFFIX)(DATA_TYPE dst, DATA_TYPE src2,
104 DATA_TYPE src3)
105 {
106 int cf, pf, af, zf, sf, of;
107 DATA_TYPE src1 = dst + src2 + src3;
108
109 cf = (src3 ? src1 <= src2 : src1 < src2);
110 pf = parity_table[(uint8_t)dst];
111 af = (dst ^ src1 ^ src2) & 0x10;
112 zf = (dst == 0) << 6;
113 sf = lshift(dst, 8 - DATA_BITS) & 0x80;
114 of = lshift((src1 ^ src2) & (src1 ^ dst), 12 - DATA_BITS) & CC_O;
115 return cf | pf | af | zf | sf | of;
116 }
117
118 static int glue(compute_c_sbb, SUFFIX)(DATA_TYPE dst, DATA_TYPE src2,
119 DATA_TYPE src3)
120 {
121 DATA_TYPE src1 = dst + src2 + src3;
122
123 return (src3 ? src1 <= src2 : src1 < src2);
124 }
125
126 static int glue(compute_all_logic, SUFFIX)(DATA_TYPE dst, DATA_TYPE src1)
127 {
128 int cf, pf, af, zf, sf, of;
129
130 cf = 0;
131 pf = parity_table[(uint8_t)dst];
132 af = 0;
133 zf = (dst == 0) * CC_Z;
134 sf = lshift(dst, 8 - DATA_BITS) & CC_S;
135 of = 0;
136 return cf | pf | af | zf | sf | of;
137 }
138
139 static int glue(compute_all_inc, SUFFIX)(DATA_TYPE dst, DATA_TYPE src1)
140 {
141 int cf, pf, af, zf, sf, of;
142 DATA_TYPE src2;
143
144 cf = src1;
145 src1 = dst - 1;
146 src2 = 1;
147 pf = parity_table[(uint8_t)dst];
148 af = (dst ^ src1 ^ src2) & CC_A;
149 zf = (dst == 0) * CC_Z;
150 sf = lshift(dst, 8 - DATA_BITS) & CC_S;
151 of = (dst == SIGN_MASK) * CC_O;
152 return cf | pf | af | zf | sf | of;
153 }
154
155 static int glue(compute_all_dec, SUFFIX)(DATA_TYPE dst, DATA_TYPE src1)
156 {
157 int cf, pf, af, zf, sf, of;
158 DATA_TYPE src2;
159
160 cf = src1;
161 src1 = dst + 1;
162 src2 = 1;
163 pf = parity_table[(uint8_t)dst];
164 af = (dst ^ src1 ^ src2) & CC_A;
165 zf = (dst == 0) * CC_Z;
166 sf = lshift(dst, 8 - DATA_BITS) & CC_S;
167 of = (dst == SIGN_MASK - 1) * CC_O;
168 return cf | pf | af | zf | sf | of;
169 }
170
171 static int glue(compute_all_shl, SUFFIX)(DATA_TYPE dst, DATA_TYPE src1)
172 {
173 int cf, pf, af, zf, sf, of;
174
175 cf = (src1 >> (DATA_BITS - 1)) & CC_C;
176 pf = parity_table[(uint8_t)dst];
177 af = 0; /* undefined */
178 zf = (dst == 0) * CC_Z;
179 sf = lshift(dst, 8 - DATA_BITS) & CC_S;
180 /* of is defined iff shift count == 1 */
181 of = lshift(src1 ^ dst, 12 - DATA_BITS) & CC_O;
182 return cf | pf | af | zf | sf | of;
183 }
184
185 static int glue(compute_c_shl, SUFFIX)(DATA_TYPE dst, DATA_TYPE src1)
186 {
187 return (src1 >> (DATA_BITS - 1)) & CC_C;
188 }
189
190 static int glue(compute_all_sar, SUFFIX)(DATA_TYPE dst, DATA_TYPE src1)
191 {
192 int cf, pf, af, zf, sf, of;
193
194 cf = src1 & 1;
195 pf = parity_table[(uint8_t)dst];
196 af = 0; /* undefined */
197 zf = (dst == 0) * CC_Z;
198 sf = lshift(dst, 8 - DATA_BITS) & CC_S;
199 /* of is defined iff shift count == 1 */
200 of = lshift(src1 ^ dst, 12 - DATA_BITS) & CC_O;
201 return cf | pf | af | zf | sf | of;
202 }
203
204 /* NOTE: we compute the flags like the P4. On olders CPUs, only OF and
205 CF are modified and it is slower to do that. Note as well that we
206 don't truncate SRC1 for computing carry to DATA_TYPE. */
207 static int glue(compute_all_mul, SUFFIX)(DATA_TYPE dst, target_long src1)
208 {
209 int cf, pf, af, zf, sf, of;
210
211 cf = (src1 != 0);
212 pf = parity_table[(uint8_t)dst];
213 af = 0; /* undefined */
214 zf = (dst == 0) * CC_Z;
215 sf = lshift(dst, 8 - DATA_BITS) & CC_S;
216 of = cf * CC_O;
217 return cf | pf | af | zf | sf | of;
218 }
219
220 static int glue(compute_all_bmilg, SUFFIX)(DATA_TYPE dst, DATA_TYPE src1)
221 {
222 int cf, pf, af, zf, sf, of;
223
224 cf = (src1 == 0);
225 pf = 0; /* undefined */
226 af = 0; /* undefined */
227 zf = (dst == 0) * CC_Z;
228 sf = lshift(dst, 8 - DATA_BITS) & CC_S;
229 of = 0;
230 return cf | pf | af | zf | sf | of;
231 }
232
233 static int glue(compute_c_bmilg, SUFFIX)(DATA_TYPE dst, DATA_TYPE src1)
234 {
235 return src1 == 0;
236 }
237
238 #undef DATA_BITS
239 #undef SIGN_MASK
240 #undef DATA_TYPE
241 #undef DATA_MASK
242 #undef SUFFIX