1/*
2 *  i386 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, write to the Free Software
18 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA  02110-1301 USA
19 */
20#define DATA_BITS (1 << (3 + SHIFT))
21#define SHIFT_MASK (DATA_BITS - 1)
22#define SIGN_MASK (((target_ulong)1) << (DATA_BITS - 1))
23#if DATA_BITS <= 32
24#define SHIFT1_MASK 0x1f
25#else
26#define SHIFT1_MASK 0x3f
27#endif
28
29#if DATA_BITS == 8
30#define SUFFIX b
31#define DATA_TYPE uint8_t
32#define DATA_STYPE int8_t
33#define DATA_MASK 0xff
34#elif DATA_BITS == 16
35#define SUFFIX w
36#define DATA_TYPE uint16_t
37#define DATA_STYPE int16_t
38#define DATA_MASK 0xffff
39#elif DATA_BITS == 32
40#define SUFFIX l
41#define DATA_TYPE uint32_t
42#define DATA_STYPE int32_t
43#define DATA_MASK 0xffffffff
44#elif DATA_BITS == 64
45#define SUFFIX q
46#define DATA_TYPE uint64_t
47#define DATA_STYPE int64_t
48#define DATA_MASK 0xffffffffffffffffULL
49#else
50#error unhandled operand size
51#endif
52
53/* dynamic flags computation */
54
55static int glue(compute_all_add, SUFFIX)(void)
56{
57    int cf, pf, af, zf, sf, of;
58    target_long src1, src2;
59    src1 = CC_SRC;
60    src2 = CC_DST - CC_SRC;
61    cf = (DATA_TYPE)CC_DST < (DATA_TYPE)src1;
62    pf = parity_table[(uint8_t)CC_DST];
63    af = (CC_DST ^ src1 ^ src2) & 0x10;
64    zf = ((DATA_TYPE)CC_DST == 0) << 6;
65    sf = lshift(CC_DST, 8 - DATA_BITS) & 0x80;
66    of = lshift((src1 ^ src2 ^ -1) & (src1 ^ CC_DST), 12 - DATA_BITS) & CC_O;
67    return cf | pf | af | zf | sf | of;
68}
69
70static int glue(compute_c_add, SUFFIX)(void)
71{
72    int cf;
73    target_long src1;
74    src1 = CC_SRC;
75    cf = (DATA_TYPE)CC_DST < (DATA_TYPE)src1;
76    return cf;
77}
78
79static int glue(compute_all_adc, SUFFIX)(void)
80{
81    int cf, pf, af, zf, sf, of;
82    target_long src1, src2;
83    src1 = CC_SRC;
84    src2 = CC_DST - CC_SRC - 1;
85    cf = (DATA_TYPE)CC_DST <= (DATA_TYPE)src1;
86    pf = parity_table[(uint8_t)CC_DST];
87    af = (CC_DST ^ src1 ^ src2) & 0x10;
88    zf = ((DATA_TYPE)CC_DST == 0) << 6;
89    sf = lshift(CC_DST, 8 - DATA_BITS) & 0x80;
90    of = lshift((src1 ^ src2 ^ -1) & (src1 ^ CC_DST), 12 - DATA_BITS) & CC_O;
91    return cf | pf | af | zf | sf | of;
92}
93
94static int glue(compute_c_adc, SUFFIX)(void)
95{
96    int cf;
97    target_long src1;
98    src1 = CC_SRC;
99    cf = (DATA_TYPE)CC_DST <= (DATA_TYPE)src1;
100    return cf;
101}
102
103static int glue(compute_all_sub, SUFFIX)(void)
104{
105    int cf, pf, af, zf, sf, of;
106    target_long src1, src2;
107    src1 = CC_DST + CC_SRC;
108    src2 = CC_SRC;
109    cf = (DATA_TYPE)src1 < (DATA_TYPE)src2;
110    pf = parity_table[(uint8_t)CC_DST];
111    af = (CC_DST ^ src1 ^ src2) & 0x10;
112    zf = ((DATA_TYPE)CC_DST == 0) << 6;
113    sf = lshift(CC_DST, 8 - DATA_BITS) & 0x80;
114    of = lshift((src1 ^ src2) & (src1 ^ CC_DST), 12 - DATA_BITS) & CC_O;
115    return cf | pf | af | zf | sf | of;
116}
117
118static int glue(compute_c_sub, SUFFIX)(void)
119{
120    int cf;
121    target_long src1, src2;
122    src1 = CC_DST + CC_SRC;
123    src2 = CC_SRC;
124    cf = (DATA_TYPE)src1 < (DATA_TYPE)src2;
125    return cf;
126}
127
128static int glue(compute_all_sbb, SUFFIX)(void)
129{
130    int cf, pf, af, zf, sf, of;
131    target_long src1, src2;
132    src1 = CC_DST + CC_SRC + 1;
133    src2 = CC_SRC;
134    cf = (DATA_TYPE)src1 <= (DATA_TYPE)src2;
135    pf = parity_table[(uint8_t)CC_DST];
136    af = (CC_DST ^ src1 ^ src2) & 0x10;
137    zf = ((DATA_TYPE)CC_DST == 0) << 6;
138    sf = lshift(CC_DST, 8 - DATA_BITS) & 0x80;
139    of = lshift((src1 ^ src2) & (src1 ^ CC_DST), 12 - DATA_BITS) & CC_O;
140    return cf | pf | af | zf | sf | of;
141}
142
143static int glue(compute_c_sbb, SUFFIX)(void)
144{
145    int cf;
146    target_long src1, src2;
147    src1 = CC_DST + CC_SRC + 1;
148    src2 = CC_SRC;
149    cf = (DATA_TYPE)src1 <= (DATA_TYPE)src2;
150    return cf;
151}
152
153static int glue(compute_all_logic, SUFFIX)(void)
154{
155    int cf, pf, af, zf, sf, of;
156    cf = 0;
157    pf = parity_table[(uint8_t)CC_DST];
158    af = 0;
159    zf = ((DATA_TYPE)CC_DST == 0) << 6;
160    sf = lshift(CC_DST, 8 - DATA_BITS) & 0x80;
161    of = 0;
162    return cf | pf | af | zf | sf | of;
163}
164
165static int glue(compute_c_logic, SUFFIX)(void)
166{
167    return 0;
168}
169
170static int glue(compute_all_inc, SUFFIX)(void)
171{
172    int cf, pf, af, zf, sf, of;
173    target_long src1, src2;
174    src1 = CC_DST - 1;
175    src2 = 1;
176    cf = CC_SRC;
177    pf = parity_table[(uint8_t)CC_DST];
178    af = (CC_DST ^ src1 ^ src2) & 0x10;
179    zf = ((DATA_TYPE)CC_DST == 0) << 6;
180    sf = lshift(CC_DST, 8 - DATA_BITS) & 0x80;
181    of = ((CC_DST & DATA_MASK) == SIGN_MASK) << 11;
182    return cf | pf | af | zf | sf | of;
183}
184
185#if DATA_BITS == 32
186static int glue(compute_c_inc, SUFFIX)(void)
187{
188    return CC_SRC;
189}
190#endif
191
192static int glue(compute_all_dec, SUFFIX)(void)
193{
194    int cf, pf, af, zf, sf, of;
195    target_long src1, src2;
196    src1 = CC_DST + 1;
197    src2 = 1;
198    cf = CC_SRC;
199    pf = parity_table[(uint8_t)CC_DST];
200    af = (CC_DST ^ src1 ^ src2) & 0x10;
201    zf = ((DATA_TYPE)CC_DST == 0) << 6;
202    sf = lshift(CC_DST, 8 - DATA_BITS) & 0x80;
203    of = ((CC_DST & DATA_MASK) == ((target_ulong)SIGN_MASK - 1)) << 11;
204    return cf | pf | af | zf | sf | of;
205}
206
207static int glue(compute_all_shl, SUFFIX)(void)
208{
209    int cf, pf, af, zf, sf, of;
210    cf = (CC_SRC >> (DATA_BITS - 1)) & CC_C;
211    pf = parity_table[(uint8_t)CC_DST];
212    af = 0; /* undefined */
213    zf = ((DATA_TYPE)CC_DST == 0) << 6;
214    sf = lshift(CC_DST, 8 - DATA_BITS) & 0x80;
215    /* of is defined if shift count == 1 */
216    of = lshift(CC_SRC ^ CC_DST, 12 - DATA_BITS) & CC_O;
217    return cf | pf | af | zf | sf | of;
218}
219
220static int glue(compute_c_shl, SUFFIX)(void)
221{
222    return (CC_SRC >> (DATA_BITS - 1)) & CC_C;
223}
224
225#if DATA_BITS == 32
226static int glue(compute_c_sar, SUFFIX)(void)
227{
228    return CC_SRC & 1;
229}
230#endif
231
232static int glue(compute_all_sar, SUFFIX)(void)
233{
234    int cf, pf, af, zf, sf, of;
235    cf = CC_SRC & 1;
236    pf = parity_table[(uint8_t)CC_DST];
237    af = 0; /* undefined */
238    zf = ((DATA_TYPE)CC_DST == 0) << 6;
239    sf = lshift(CC_DST, 8 - DATA_BITS) & 0x80;
240    /* of is defined if shift count == 1 */
241    of = lshift(CC_SRC ^ CC_DST, 12 - DATA_BITS) & CC_O;
242    return cf | pf | af | zf | sf | of;
243}
244
245#if DATA_BITS == 32
246static int glue(compute_c_mul, SUFFIX)(void)
247{
248    int cf;
249    cf = (CC_SRC != 0);
250    return cf;
251}
252#endif
253
254/* NOTE: we compute the flags like the P4. On olders CPUs, only OF and
255   CF are modified and it is slower to do that. */
256static int glue(compute_all_mul, SUFFIX)(void)
257{
258    int cf, pf, af, zf, sf, of;
259    cf = (CC_SRC != 0);
260    pf = parity_table[(uint8_t)CC_DST];
261    af = 0; /* undefined */
262    zf = ((DATA_TYPE)CC_DST == 0) << 6;
263    sf = lshift(CC_DST, 8 - DATA_BITS) & 0x80;
264    of = cf << 11;
265    return cf | pf | af | zf | sf | of;
266}
267
268/* shifts */
269
270target_ulong glue(helper_rcl, SUFFIX)(target_ulong t0, target_ulong t1)
271{
272    int count, eflags;
273    target_ulong src;
274    target_long res;
275
276    count = t1 & SHIFT1_MASK;
277#if DATA_BITS == 16
278    count = rclw_table[count];
279#elif DATA_BITS == 8
280    count = rclb_table[count];
281#endif
282    if (count) {
283        eflags = helper_cc_compute_all(CC_OP);
284        t0 &= DATA_MASK;
285        src = t0;
286        res = (t0 << count) | ((target_ulong)(eflags & CC_C) << (count - 1));
287        if (count > 1)
288            res |= t0 >> (DATA_BITS + 1 - count);
289        t0 = res;
290        env->cc_tmp = (eflags & ~(CC_C | CC_O)) |
291            (lshift(src ^ t0, 11 - (DATA_BITS - 1)) & CC_O) |
292            ((src >> (DATA_BITS - count)) & CC_C);
293    } else {
294        env->cc_tmp = -1;
295    }
296    return t0;
297}
298
299target_ulong glue(helper_rcr, SUFFIX)(target_ulong t0, target_ulong t1)
300{
301    int count, eflags;
302    target_ulong src;
303    target_long res;
304
305    count = t1 & SHIFT1_MASK;
306#if DATA_BITS == 16
307    count = rclw_table[count];
308#elif DATA_BITS == 8
309    count = rclb_table[count];
310#endif
311    if (count) {
312        eflags = helper_cc_compute_all(CC_OP);
313        t0 &= DATA_MASK;
314        src = t0;
315        res = (t0 >> count) | ((target_ulong)(eflags & CC_C) << (DATA_BITS - count));
316        if (count > 1)
317            res |= t0 << (DATA_BITS + 1 - count);
318        t0 = res;
319        env->cc_tmp = (eflags & ~(CC_C | CC_O)) |
320            (lshift(src ^ t0, 11 - (DATA_BITS - 1)) & CC_O) |
321            ((src >> (count - 1)) & CC_C);
322    } else {
323        env->cc_tmp = -1;
324    }
325    return t0;
326}
327
328#undef DATA_BITS
329#undef SHIFT_MASK
330#undef SHIFT1_MASK
331#undef SIGN_MASK
332#undef DATA_TYPE
333#undef DATA_STYPE
334#undef DATA_MASK
335#undef SUFFIX
336