gdb/regcache.h

   1 /* Cache and manage the values of registers for GDB, the GNU debugger.
   2
   3    Copyright 1986, 1987, 1989, 1991, 1994, 1995, 1996, 1998, 2000,
   4    2001, 2002 Free Software Foundation, Inc.
   5
   6    This file is part of GDB.
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 2 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program; if not, write to the Free Software
  20    Foundation, Inc., 59 Temple Place - Suite 330,
  21    Boston, MA 02111-1307, USA.  */
  22
  23 #ifndef REGCACHE_H
  24 #define REGCACHE_H
  25
  26 struct regcache;
  27 struct gdbarch;
  28
  29 extern struct regcache *current_regcache;
  30
  31 void regcache_xfree (struct regcache *regcache);
  32 struct cleanup *make_cleanup_regcache_xfree (struct regcache *regcache);
  33 struct regcache *regcache_xmalloc (struct gdbarch *gdbarch);
  34
  35 /* Return REGCACHE's architecture.  */
  36
  37 extern struct gdbarch *get_regcache_arch (const struct regcache *regcache);
  38
  39 /* Transfer a raw register [0..NUM_REGS) between core-gdb and the
  40    regcache. */
  41
  42 void regcache_raw_read (struct regcache *regcache, int rawnum, void *buf);
  43 void regcache_raw_write (struct regcache *regcache, int rawnum,
  44                          const void *buf);
  45 extern void regcache_raw_read_signed (struct regcache *regcache,
  46                                       int regnum, LONGEST *val);
  47 extern void regcache_raw_read_unsigned (struct regcache *regcache,
  48                                         int regnum, ULONGEST *val);
  49 extern void regcache_raw_write_signed (struct regcache *regcache,
  50                                        int regnum, LONGEST val);
  51 extern void regcache_raw_write_unsigned (struct regcache *regcache,
  52                                          int regnum, ULONGEST val);
  53
  54 /* Partial transfer of a raw registers.  These perform read, modify,
  55    write style operations.  */
  56
  57 void regcache_raw_read_part (struct regcache *regcache, int regnum,
  58                              int offset, int len, void *buf);
  59 void regcache_raw_write_part (struct regcache *regcache, int regnum,
  60                               int offset, int len, const void *buf);
  61
  62 int regcache_valid_p (struct regcache *regcache, int regnum);
  63
  64 /* Transfer a cooked register [0..NUM_REGS+NUM_PSEUDO_REGS).  */
  65 void regcache_cooked_read (struct regcache *regcache, int rawnum, void *buf);
  66 void regcache_cooked_write (struct regcache *regcache, int rawnum,
  67                             const void *buf);
  68
  69 /* NOTE: cagney/2002-08-13: At present GDB has no reliable mechanism
  70    for indicating when a ``cooked'' register was constructed from
  71    invalid or unavailable ``raw'' registers.  One fairly easy way of
  72    adding such a mechanism would be for the cooked functions to return
  73    a register valid indication.  Given the possibility of such a
  74    change, the extract functions below use a reference parameter,
  75    rather than a function result.  */
  76
  77 /* Read a register as a signed/unsigned quantity.  */
  78 extern void regcache_cooked_read_signed (struct regcache *regcache,
  79                                          int regnum, LONGEST *val);
  80 extern void regcache_cooked_read_unsigned (struct regcache *regcache,
  81                                            int regnum, ULONGEST *val);
  82 extern void regcache_cooked_write_signed (struct regcache *regcache,
  83                                           int regnum, LONGEST val);
  84 extern void regcache_cooked_write_unsigned (struct regcache *regcache,
  85                                             int regnum, ULONGEST val);
  86
  87 /* Partial transfer of a cooked register.  These perform read, modify,
  88    write style operations.  */
  89
  90 void regcache_cooked_read_part (struct regcache *regcache, int regnum,
  91                                 int offset, int len, void *buf);
  92 void regcache_cooked_write_part (struct regcache *regcache, int regnum,
  93                                  int offset, int len, const void *buf);
  94
  95 /* Transfer a raw register [0..NUM_REGS) between the regcache and the
  96    target.  These functions are called by the target in response to a
  97    target_fetch_registers() or target_store_registers().  */
  98
  99 extern void regcache_raw_supply (struct regcache *regcache,
 100                                  int regnum, const void *buf);
 101 extern void regcache_raw_collect (const struct regcache *regcache,
 102                                   int regnum, void *buf);
 103
 104
 105 /* The register's ``offset''.
 106
 107    FIXME: cagney/2002-11-07: The frame_register() function, when
 108    specifying the real location of a register, does so using that
 109    registers offset in the register cache.  That offset is then used
 110    by valops.c to determine the location of the register.  The code
 111    should instead use the register's number and a location expression
 112    to describe a value spread across multiple registers or memory.  */
 113
 114 extern int register_offset_hack (struct gdbarch *gdbarch, int regnum);
 115
 116
 117 /* The type of a register.  This function is slightly more efficient
 118    then its gdbarch vector counterpart since it returns a precomputed
 119    value stored in a table.
 120
 121    NOTE: cagney/2002-08-17: The original macro was called
 122    DEPRECATED_REGISTER_VIRTUAL_TYPE.  This was because the register
 123    could have different raw and cooked (nee virtual) representations.
 124    The CONVERTABLE methods being used to convert between the two
 125    representations.  Current code does not do this.  Instead, the
 126    first [0..NUM_REGS) registers are 1:1 raw:cooked, and the type
 127    exactly describes the register's representation.  Consequently, the
 128    ``virtual'' has been dropped.
 129
 130    FIXME: cagney/2002-08-17: A number of architectures, including the
 131    MIPS, are currently broken in this regard.  */
 132
 133 extern struct type *register_type (struct gdbarch *gdbarch, int regnum);
 134
 135
 136 /* Return the size of register REGNUM.  All registers should have only
 137    one size.
 138
 139    FIXME: cagney/2003-02-28:
 140
 141    Unfortunately, thanks to some legacy architectures, this doesn't
 142    hold.  A register's cooked (nee virtual) and raw size can differ
 143    (see MIPS).  Such architectures should be using different register
 144    numbers for the different sized views of identical registers.
 145
 146    Anyway, the up-shot is that, until that mess is fixed, core code
 147    can end up being very confused - should the RAW or VIRTUAL size be
 148    used?  As a rule of thumb, use DEPRECATED_REGISTER_VIRTUAL_SIZE in
 149    cooked code, but with the comment:
 150
 151    OK: REGISTER_VIRTUAL_SIZE
 152
 153    or just
 154
 155    OK
 156
 157    appended to the end of the line.  */
 158
 159 extern int register_size (struct gdbarch *gdbarch, int regnum);
 160
 161
 162 /* Save/restore a register cache.  The set of registers saved /
 163    restored into the DST regcache determined by the save_reggroup /
 164    restore_reggroup respectively.  COOKED_READ returns zero iff the
 165    register's value can't be returned.  */
 166
 167 typedef int (regcache_cooked_read_ftype) (void *src, int regnum, void *buf);
 168
 169 extern void regcache_save (struct regcache *dst,
 170                            regcache_cooked_read_ftype *cooked_read,
 171                            void *src);
 172 extern void regcache_restore (struct regcache *dst,
 173                               regcache_cooked_read_ftype *cooked_read,
 174                               void *src);
 175
 176 /* Copy/duplicate the contents of a register cache.  By default, the
 177    operation is pass-through.  Writes to DST and reads from SRC will
 178    go through to the target.
 179
 180    The ``cpy'' functions can not have overlapping SRC and DST buffers.
 181
 182    ``no passthrough'' versions do not go through to the target.  They
 183    only transfer values already in the cache.  */
 184
 185 extern struct regcache *regcache_dup (struct regcache *regcache);
 186 extern struct regcache *regcache_dup_no_passthrough (struct regcache *regcache);
 187 extern void regcache_cpy (struct regcache *dest, struct regcache *src);
 188 extern void regcache_cpy_no_passthrough (struct regcache *dest, struct regcache *src);
 189
 190 /* NOTE: cagney/2002-11-02: The below have been superseded by the
 191    regcache_cooked_*() functions found above, and the frame_*()
 192    functions found in "frame.h".  Take care though, often more than a
 193    simple substitution is required when updating the code.  The
 194    change, as far as practical, should avoid adding references to
 195    global variables (e.g., current_regcache, current_frame,
 196    current_gdbarch or deprecated_selected_frame) and instead refer to
 197    the FRAME or REGCACHE that has been passed into the containing
 198    function as parameters.  Consequently, the change typically
 199    involves modifying the containing function so that it takes a FRAME
 200    or REGCACHE parameter.  In the case of an architecture vector
 201    method, there should already be a non-deprecated variant that is
 202    parameterized with FRAME or REGCACHE.  */
 203
 204 extern char *deprecated_grub_regcache_for_registers (struct regcache *);
 205 extern void deprecated_read_register_gen (int regnum, char *myaddr);
 206 extern void deprecated_write_register_gen (int regnum, char *myaddr);
 207 extern void deprecated_read_register_bytes (int regbyte, char *myaddr,
 208                                             int len);
 209 extern void deprecated_write_register_bytes (int regbyte, char *myaddr,
 210                                              int len);
 211
 212 /* Character array containing the current state of each register
 213    (unavailable<0, invalid=0, valid>0) for the most recently
 214    referenced thread.  This global is often found in close proximity
 215    to code that is directly manipulating the deprecated_registers[]
 216    array.  In such cases, it should be possible to replace the lot
 217    with a call to regcache_raw_supply().  If you find yourself in dire
 218    straits, still needing access to the cache status bit, the
 219    regcache_valid_p() and set_register_cached() functions are
 220    available.  */
 221 extern signed char *deprecated_register_valid;
 222
 223 /* Character array containing an image of the inferior programs'
 224    registers for the most recently referenced thread.
 225
 226    NOTE: cagney/2002-11-14: Target side code should be using
 227    regcache_raw_supply() and/or regcache_collect() while architecture
 228    side code should use the more generic regcache methods.  */
 229
 230 extern char *deprecated_registers;
 231
 232 /* NOTE: cagney/2002-11-05: This function, and its co-conspirator
 233    deprecated_registers[], have been superseeded by
 234    regcache_raw_supply().  */
 235 extern void deprecated_registers_fetched (void);
 236
 237 extern int register_cached (int regnum);
 238
 239 extern void set_register_cached (int regnum, int state);
 240
 241 extern void registers_changed (void);
 242
 243
 244 /* Rename to read_unsigned_register()? */
 245 extern ULONGEST read_register (int regnum);
 246
 247 /* Rename to read_unsigned_register_pid()? */
 248 extern ULONGEST read_register_pid (int regnum, ptid_t ptid);
 249
 250 extern void write_register (int regnum, LONGEST val);
 251
 252 extern void write_register_pid (int regnum, CORE_ADDR val, ptid_t ptid);
 253
 254 #endif /* REGCACHE_H */