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