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1/*
2 * Generic thunking code to convert data between host and target CPU
5fafdf24 3 *
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4 * Copyright (c) 2003 Fabrice Bellard
5 *
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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.
31e31b8a 10 *
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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.
31e31b8a 15 *
3ef693a0 16 * You should have received a copy of the GNU Lesser General Public
8167ee88 17 * License along with this library; if not, see <http://www.gnu.org/licenses/>.
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18 */
19#include <stdlib.h>
20#include <stdio.h>
21#include <stdarg.h>
22
3ef693a0 23#include "qemu.h"
022c62cb 24#include "exec/user/thunk.h"
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25
26//#define DEBUG
27
28#define MAX_STRUCTS 128
29
30/* XXX: make it dynamic */
24374901 31StructEntry struct_entries[MAX_STRUCTS];
31e31b8a 32
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33static const argtype *thunk_type_next_ptr(const argtype *type_ptr);
34
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35static inline const argtype *thunk_type_next(const argtype *type_ptr)
36{
37 int type;
38
39 type = *type_ptr++;
40 switch(type) {
41 case TYPE_CHAR:
42 case TYPE_SHORT:
43 case TYPE_INT:
44 case TYPE_LONGLONG:
45 case TYPE_ULONGLONG:
46 case TYPE_LONG:
47 case TYPE_ULONG:
48 case TYPE_PTRVOID:
6083abd9 49 case TYPE_OLDDEVT:
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50 return type_ptr;
51 case TYPE_PTR:
26553115 52 return thunk_type_next_ptr(type_ptr);
31e31b8a 53 case TYPE_ARRAY:
26553115 54 return thunk_type_next_ptr(type_ptr + 1);
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55 case TYPE_STRUCT:
56 return type_ptr + 1;
57 default:
58 return NULL;
59 }
60}
61
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62static const argtype *thunk_type_next_ptr(const argtype *type_ptr)
63{
64 return thunk_type_next(type_ptr);
65}
66
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67void thunk_register_struct(int id, const char *name, const argtype *types)
68{
69 const argtype *type_ptr;
70 StructEntry *se;
71 int nb_fields, offset, max_align, align, size, i, j;
72
73 se = struct_entries + id;
3b46e624 74
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75 /* first we count the number of fields */
76 type_ptr = types;
77 nb_fields = 0;
78 while (*type_ptr != TYPE_NULL) {
79 type_ptr = thunk_type_next(type_ptr);
80 nb_fields++;
81 }
82 se->field_types = types;
83 se->nb_fields = nb_fields;
84 se->name = name;
85#ifdef DEBUG
5fafdf24 86 printf("struct %s: id=%d nb_fields=%d\n",
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87 se->name, id, se->nb_fields);
88#endif
89 /* now we can alloc the data */
90
91 for(i = 0;i < 2; i++) {
92 offset = 0;
93 max_align = 1;
94 se->field_offsets[i] = malloc(nb_fields * sizeof(int));
95 type_ptr = se->field_types;
96 for(j = 0;j < nb_fields; j++) {
97 size = thunk_type_size(type_ptr, i);
98 align = thunk_type_align(type_ptr, i);
99 offset = (offset + align - 1) & ~(align - 1);
100 se->field_offsets[i][j] = offset;
101 offset += size;
102 if (align > max_align)
103 max_align = align;
24374901 104 type_ptr = thunk_type_next(type_ptr);
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105 }
106 offset = (offset + max_align - 1) & ~(max_align - 1);
107 se->size[i] = offset;
108 se->align[i] = max_align;
109#ifdef DEBUG
5fafdf24 110 printf("%s: size=%d align=%d\n",
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111 i == THUNK_HOST ? "host" : "target", offset, max_align);
112#endif
113 }
114}
115
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116void thunk_register_struct_direct(int id, const char *name,
117 const StructEntry *se1)
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118{
119 StructEntry *se;
120 se = struct_entries + id;
121 *se = *se1;
122 se->name = name;
123}
124
125
126/* now we can define the main conversion functions */
5fafdf24 127const argtype *thunk_convert(void *dst, const void *src,
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128 const argtype *type_ptr, int to_host)
129{
130 int type;
131
132 type = *type_ptr++;
133 switch(type) {
134 case TYPE_CHAR:
135 *(uint8_t *)dst = *(uint8_t *)src;
136 break;
137 case TYPE_SHORT:
138 *(uint16_t *)dst = tswap16(*(uint16_t *)src);
139 break;
140 case TYPE_INT:
141 *(uint32_t *)dst = tswap32(*(uint32_t *)src);
142 break;
143 case TYPE_LONGLONG:
144 case TYPE_ULONGLONG:
145 *(uint64_t *)dst = tswap64(*(uint64_t *)src);
146 break;
992f48a0 147#if HOST_LONG_BITS == 32 && TARGET_ABI_BITS == 32
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148 case TYPE_LONG:
149 case TYPE_ULONG:
150 case TYPE_PTRVOID:
151 *(uint32_t *)dst = tswap32(*(uint32_t *)src);
152 break;
992f48a0 153#elif HOST_LONG_BITS == 64 && TARGET_ABI_BITS == 32
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154 case TYPE_LONG:
155 case TYPE_ULONG:
156 case TYPE_PTRVOID:
d0cd3b8d 157 if (to_host) {
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158 if (type == TYPE_LONG) {
159 /* sign extension */
160 *(uint64_t *)dst = (int32_t)tswap32(*(uint32_t *)src);
161 } else {
162 *(uint64_t *)dst = tswap32(*(uint32_t *)src);
163 }
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164 } else {
165 *(uint32_t *)dst = tswap32(*(uint64_t *)src & 0xffffffff);
166 }
167 break;
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168#elif HOST_LONG_BITS == 64 && TARGET_ABI_BITS == 64
169 case TYPE_LONG:
170 case TYPE_ULONG:
171 case TYPE_PTRVOID:
172 *(uint64_t *)dst = tswap64(*(uint64_t *)src);
173 break;
174#elif HOST_LONG_BITS == 32 && TARGET_ABI_BITS == 64
175 case TYPE_LONG:
176 case TYPE_ULONG:
177 case TYPE_PTRVOID:
178 if (to_host) {
179 *(uint32_t *)dst = tswap64(*(uint64_t *)src);
180 } else {
181 if (type == TYPE_LONG) {
182 /* sign extension */
183 *(uint64_t *)dst = tswap64(*(int32_t *)src);
184 } else {
185 *(uint64_t *)dst = tswap64(*(uint32_t *)src);
186 }
187 }
188 break;
31e31b8a 189#else
64b3ab24 190#warning unsupported conversion
31e31b8a 191#endif
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192 case TYPE_OLDDEVT:
193 {
194 uint64_t val = 0;
195 switch (thunk_type_size(type_ptr - 1, !to_host)) {
196 case 2:
197 val = *(uint16_t *)src;
198 break;
199 case 4:
200 val = *(uint32_t *)src;
201 break;
202 case 8:
203 val = *(uint64_t *)src;
204 break;
205 }
206 switch (thunk_type_size(type_ptr - 1, to_host)) {
207 case 2:
208 *(uint16_t *)dst = tswap16(val);
209 break;
210 case 4:
211 *(uint32_t *)dst = tswap32(val);
212 break;
213 case 8:
214 *(uint64_t *)dst = tswap64(val);
215 break;
216 }
217 break;
218 }
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219 case TYPE_ARRAY:
220 {
221 int array_length, i, dst_size, src_size;
222 const uint8_t *s;
223 uint8_t *d;
224
225 array_length = *type_ptr++;
226 dst_size = thunk_type_size(type_ptr, to_host);
227 src_size = thunk_type_size(type_ptr, 1 - to_host);
228 d = dst;
229 s = src;
230 for(i = 0;i < array_length; i++) {
231 thunk_convert(d, s, type_ptr, to_host);
232 d += dst_size;
233 s += src_size;
234 }
235 type_ptr = thunk_type_next(type_ptr);
236 }
237 break;
238 case TYPE_STRUCT:
239 {
240 int i;
241 const StructEntry *se;
242 const uint8_t *s;
243 uint8_t *d;
244 const argtype *field_types;
245 const int *dst_offsets, *src_offsets;
3b46e624 246
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247 se = struct_entries + *type_ptr++;
248 if (se->convert[0] != NULL) {
249 /* specific conversion is needed */
250 (*se->convert[to_host])(dst, src);
251 } else {
252 /* standard struct conversion */
253 field_types = se->field_types;
254 dst_offsets = se->field_offsets[to_host];
255 src_offsets = se->field_offsets[1 - to_host];
256 d = dst;
257 s = src;
258 for(i = 0;i < se->nb_fields; i++) {
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259 field_types = thunk_convert(d + dst_offsets[i],
260 s + src_offsets[i],
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261 field_types, to_host);
262 }
263 }
264 }
265 break;
266 default:
267 fprintf(stderr, "Invalid type 0x%x\n", type);
268 break;
269 }
270 return type_ptr;
271}
272
273/* from em86 */
274
275/* Utility function: Table-driven functions to translate bitmasks
276 * between X86 and Alpha formats...
277 */
5fafdf24 278unsigned int target_to_host_bitmask(unsigned int x86_mask,
b39bc503 279 const bitmask_transtbl * trans_tbl)
31e31b8a 280{
b39bc503 281 const bitmask_transtbl *btp;
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282 unsigned int alpha_mask = 0;
283
284 for(btp = trans_tbl; btp->x86_mask && btp->alpha_mask; btp++) {
285 if((x86_mask & btp->x86_mask) == btp->x86_bits) {
286 alpha_mask |= btp->alpha_bits;
287 }
288 }
289 return(alpha_mask);
290}
291
5fafdf24 292unsigned int host_to_target_bitmask(unsigned int alpha_mask,
b39bc503 293 const bitmask_transtbl * trans_tbl)
31e31b8a 294{
b39bc503 295 const bitmask_transtbl *btp;
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296 unsigned int x86_mask = 0;
297
298 for(btp = trans_tbl; btp->x86_mask && btp->alpha_mask; btp++) {
299 if((alpha_mask & btp->alpha_mask) == btp->alpha_bits) {
7a987127 300 x86_mask |= btp->x86_bits;
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301 }
302 }
303 return(x86_mask);
304}
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305
306#ifndef NO_THUNK_TYPE_SIZE
307int thunk_type_size_array(const argtype *type_ptr, int is_host)
308{
309 return thunk_type_size(type_ptr, is_host);
310}
311
312int thunk_type_align_array(const argtype *type_ptr, int is_host)
313{
314 return thunk_type_align(type_ptr, is_host);
315}
316#endif /* ndef NO_THUNK_TYPE_SIZE */