thunk.h

   1 /*
   2  *  Generic thunking code to convert data between host and target CPU
   3  *
   4  *  Copyright (c) 2003 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  19  */
  20 #ifndef THUNK_H
  21 #define THUNK_H
  22
  23 #include <inttypes.h>
  24 #include "cpu.h"
  25
  26 /* types enums definitions */
  27
  28 typedef enum argtype {
  29     TYPE_NULL,
  30     TYPE_CHAR,
  31     TYPE_SHORT,
  32     TYPE_INT,
  33     TYPE_LONG,
  34     TYPE_ULONG,
  35     TYPE_PTRVOID, /* pointer on unknown data */
  36     TYPE_LONGLONG,
  37     TYPE_ULONGLONG,
  38     TYPE_PTR,
  39     TYPE_ARRAY,
  40     TYPE_STRUCT,
  41 } argtype;
  42
  43 #define MK_PTR(type) TYPE_PTR, type
  44 #define MK_ARRAY(type, size) TYPE_ARRAY, size, type
  45 #define MK_STRUCT(id) TYPE_STRUCT, id
  46
  47 #define THUNK_TARGET 0
  48 #define THUNK_HOST   1
  49
  50 typedef struct {
  51     /* standard struct handling */
  52     const argtype *field_types;
  53     int nb_fields;
  54     int *field_offsets[2];
  55     /* special handling */
  56     void (*convert[2])(void *dst, const void *src);
  57     int size[2];
  58     int align[2];
  59     const char *name;
  60 } StructEntry;
  61
  62 /* Translation table for bitmasks... */
  63 typedef struct bitmask_transtbl {
  64         unsigned int    x86_mask;
  65         unsigned int    x86_bits;
  66         unsigned int    alpha_mask;
  67         unsigned int    alpha_bits;
  68 } bitmask_transtbl;
  69
  70 void thunk_register_struct(int id, const char *name, const argtype *types);
  71 void thunk_register_struct_direct(int id, const char *name,
  72                                   const StructEntry *se1);
  73 const argtype *thunk_convert(void *dst, const void *src,
  74                              const argtype *type_ptr, int to_host);
  75 #ifndef NO_THUNK_TYPE_SIZE
  76
  77 extern StructEntry struct_entries[];
  78
  79 int thunk_type_size_array(const argtype *type_ptr, int is_host);
  80 int thunk_type_align_array(const argtype *type_ptr, int is_host);
  81
  82 static inline int thunk_type_size(const argtype *type_ptr, int is_host)
  83 {
  84     int type, size;
  85     const StructEntry *se;
  86
  87     type = *type_ptr;
  88     switch(type) {
  89     case TYPE_CHAR:
  90         return 1;
  91     case TYPE_SHORT:
  92         return 2;
  93     case TYPE_INT:
  94         return 4;
  95     case TYPE_LONGLONG:
  96     case TYPE_ULONGLONG:
  97         return 8;
  98     case TYPE_LONG:
  99     case TYPE_ULONG:
 100     case TYPE_PTRVOID:
 101     case TYPE_PTR:
 102         if (is_host) {
 103             return HOST_LONG_SIZE;
 104         } else {
 105             return TARGET_ABI_BITS / 8;
 106         }
 107         break;
 108     case TYPE_ARRAY:
 109         size = type_ptr[1];
 110         return size * thunk_type_size_array(type_ptr + 2, is_host);
 111     case TYPE_STRUCT:
 112         se = struct_entries + type_ptr[1];
 113         return se->size[is_host];
 114     default:
 115         return -1;
 116     }
 117 }
 118
 119 static inline int thunk_type_align(const argtype *type_ptr, int is_host)
 120 {
 121     int type;
 122     const StructEntry *se;
 123
 124     type = *type_ptr;
 125     switch(type) {
 126     case TYPE_CHAR:
 127         return 1;
 128     case TYPE_SHORT:
 129         return 2;
 130     case TYPE_INT:
 131         return 4;
 132     case TYPE_LONGLONG:
 133     case TYPE_ULONGLONG:
 134         return 8;
 135     case TYPE_LONG:
 136     case TYPE_ULONG:
 137     case TYPE_PTRVOID:
 138     case TYPE_PTR:
 139         if (is_host) {
 140             return HOST_LONG_SIZE;
 141         } else {
 142             return TARGET_ABI_BITS / 8;
 143         }
 144         break;
 145     case TYPE_ARRAY:
 146         return thunk_type_align_array(type_ptr + 2, is_host);
 147     case TYPE_STRUCT:
 148         se = struct_entries + type_ptr[1];
 149         return se->align[is_host];
 150     default:
 151         return -1;
 152     }
 153 }
 154
 155 #endif /* NO_THUNK_TYPE_SIZE */
 156
 157 unsigned int target_to_host_bitmask(unsigned int x86_mask,
 158                                     const bitmask_transtbl * trans_tbl);
 159 unsigned int host_to_target_bitmask(unsigned int alpha_mask,
 160                                     const bitmask_transtbl * trans_tbl);
 161
 162 #endif