summaryrefslogtreecommitdiff
path: root/thunk.c
blob: bc9bd2881959a333ed91b9ecda58c707022cbc8a (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
/*
 *  Generic thunking code to convert data between host and target CPU
 * 
 *  Copyright (c) 2003 Fabrice Bellard
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */
#include <stdlib.h>
#include <stdio.h>
#include <stdarg.h>

#include "qemu.h"
#include "thunk.h"

//#define DEBUG

#define MAX_STRUCTS 128

/* XXX: make it dynamic */
StructEntry struct_entries[MAX_STRUCTS];

static inline const argtype *thunk_type_next(const argtype *type_ptr)
{
    int type;

    type = *type_ptr++;
    switch(type) {
    case TYPE_CHAR:
    case TYPE_SHORT:
    case TYPE_INT:
    case TYPE_LONGLONG:
    case TYPE_ULONGLONG:
    case TYPE_LONG:
    case TYPE_ULONG:
    case TYPE_PTRVOID:
        return type_ptr;
    case TYPE_PTR:
        return thunk_type_next(type_ptr);
    case TYPE_ARRAY:
        return thunk_type_next(type_ptr + 1);
    case TYPE_STRUCT:
        return type_ptr + 1;
    default:
        return NULL;
    }
}

void thunk_register_struct(int id, const char *name, const argtype *types)
{
    const argtype *type_ptr;
    StructEntry *se;
    int nb_fields, offset, max_align, align, size, i, j;

    se = struct_entries + id;
    
    /* first we count the number of fields */
    type_ptr = types;
    nb_fields = 0;
    while (*type_ptr != TYPE_NULL) {
        type_ptr = thunk_type_next(type_ptr);
        nb_fields++;
    }
    se->field_types = types;
    se->nb_fields = nb_fields;
    se->name = name;
#ifdef DEBUG
    printf("struct %s: id=%d nb_fields=%d\n", 
           se->name, id, se->nb_fields);
#endif
    /* now we can alloc the data */

    for(i = 0;i < 2; i++) {
        offset = 0;
        max_align = 1;
        se->field_offsets[i] = malloc(nb_fields * sizeof(int));
        type_ptr = se->field_types;
        for(j = 0;j < nb_fields; j++) {
            size = thunk_type_size(type_ptr, i);
            align = thunk_type_align(type_ptr, i);
            offset = (offset + align - 1) & ~(align - 1);
            se->field_offsets[i][j] = offset;
            offset += size;
            if (align > max_align)
                max_align = align;
            type_ptr = thunk_type_next(type_ptr);
        }
        offset = (offset + max_align - 1) & ~(max_align - 1);
        se->size[i] = offset;
        se->align[i] = max_align;
#ifdef DEBUG
        printf("%s: size=%d align=%d\n", 
               i == THUNK_HOST ? "host" : "target", offset, max_align);
#endif
    }
}

void thunk_register_struct_direct(int id, const char *name, StructEntry *se1)
{
    StructEntry *se;
    se = struct_entries + id;
    *se = *se1;
    se->name = name;
}


/* now we can define the main conversion functions */
const argtype *thunk_convert(void *dst, const void *src, 
                             const argtype *type_ptr, int to_host)
{
    int type;

    type = *type_ptr++;
    switch(type) {
    case TYPE_CHAR:
        *(uint8_t *)dst = *(uint8_t *)src;
        break;
    case TYPE_SHORT:
        *(uint16_t *)dst = tswap16(*(uint16_t *)src);
        break;
    case TYPE_INT:
        *(uint32_t *)dst = tswap32(*(uint32_t *)src);
        break;
    case TYPE_LONGLONG:
    case TYPE_ULONGLONG:
        *(uint64_t *)dst = tswap64(*(uint64_t *)src);
        break;
#if HOST_LONG_BITS == 32 && TARGET_LONG_BITS == 32
    case TYPE_LONG:
    case TYPE_ULONG:
    case TYPE_PTRVOID:
        *(uint32_t *)dst = tswap32(*(uint32_t *)src);
        break;
#elif HOST_LONG_BITS == 64 && TARGET_LONG_BITS == 32
    case TYPE_LONG:
    case TYPE_ULONG:
    case TYPE_PTRVOID:
        if (to_host) {
            *(uint64_t *)dst = tswap32(*(uint32_t *)src);
        } else {
            *(uint32_t *)dst = tswap32(*(uint64_t *)src & 0xffffffff);
        }
        break;
#else
#warning unsupported conversion
#endif
    case TYPE_ARRAY:
        {
            int array_length, i, dst_size, src_size;
            const uint8_t *s;
            uint8_t  *d;

            array_length = *type_ptr++;
            dst_size = thunk_type_size(type_ptr, to_host);
            src_size = thunk_type_size(type_ptr, 1 - to_host);
            d = dst;
            s = src;
            for(i = 0;i < array_length; i++) {
                thunk_convert(d, s, type_ptr, to_host);
                d += dst_size;
                s += src_size;
            }
            type_ptr = thunk_type_next(type_ptr);
        }
        break;
    case TYPE_STRUCT:
        {
            int i;
            const StructEntry *se;
            const uint8_t *s;
            uint8_t  *d;
            const argtype *field_types;
            const int *dst_offsets, *src_offsets;
            
            se = struct_entries + *type_ptr++;
            if (se->convert[0] != NULL) {
                /* specific conversion is needed */
                (*se->convert[to_host])(dst, src);
            } else {
                /* standard struct conversion */
                field_types = se->field_types;
                dst_offsets = se->field_offsets[to_host];
                src_offsets = se->field_offsets[1 - to_host];
                d = dst;
                s = src;
                for(i = 0;i < se->nb_fields; i++) {
                    field_types = thunk_convert(d + dst_offsets[i], 
                                                s + src_offsets[i], 
                                                field_types, to_host);
                }
            }
        }
        break;
    default:
        fprintf(stderr, "Invalid type 0x%x\n", type);
        break;
    }
    return type_ptr;
}

/* from em86 */

/* Utility function: Table-driven functions to translate bitmasks
 * between X86 and Alpha formats...
 */
unsigned int target_to_host_bitmask(unsigned int x86_mask, 
                                    bitmask_transtbl * trans_tbl)
{
    bitmask_transtbl *	btp;
    unsigned int	alpha_mask = 0;

    for(btp = trans_tbl; btp->x86_mask && btp->alpha_mask; btp++) {
	if((x86_mask & btp->x86_mask) == btp->x86_bits) {
	    alpha_mask |= btp->alpha_bits;
	}
    }
    return(alpha_mask);
}

unsigned int host_to_target_bitmask(unsigned int alpha_mask, 
                                    bitmask_transtbl * trans_tbl)
{
    bitmask_transtbl *	btp;
    unsigned int	x86_mask = 0;

    for(btp = trans_tbl; btp->x86_mask && btp->alpha_mask; btp++) {
	if((alpha_mask & btp->alpha_mask) == btp->alpha_bits) {
	    x86_mask |= btp->x86_bits;
	}
    }
    return(x86_mask);
}