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