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 registers saved/restored is
 159    determined by the save_reggroup and restore_reggroup (although you
 160    can't restore a register that wasn't saved as well :-).  You can
 161    only save to a read-only cache (default from regcache_xmalloc())
 162    from a live cache and you can only restore from a read-only cache
 163    to a live cache.  */
 164
 165 extern void regcache_save (struct regcache *dst, struct regcache *src);
 166 extern void regcache_restore (struct regcache *dst, struct regcache *src);
 167
 168 /* Copy/duplicate the contents of a register cache.  By default, the
 169    operation is pass-through.  Writes to DST and reads from SRC will
 170    go through to the target.
 171
 172    The ``cpy'' functions can not have overlapping SRC and DST buffers.
 173
 174    ``no passthrough'' versions do not go through to the target.  They
 175    only transfer values already in the cache.  */
 176
 177 extern struct regcache *regcache_dup (struct regcache *regcache);
 178 extern struct regcache *regcache_dup_no_passthrough (struct regcache *regcache);
 179 extern void regcache_cpy (struct regcache *dest, struct regcache *src);
 180 extern void regcache_cpy_no_passthrough (struct regcache *dest, struct regcache *src);
 181
 182 /* NOTE: cagney/2002-11-02: The below have been superseded by the
 183    regcache_cooked_*() functions found above, and the frame_*()
 184    functions found in "frame.h".  Take care though, often more than a
 185    simple substitution is required when updating the code.  The
 186    change, as far as practical, should avoid adding references to
 187    global variables (e.g., current_regcache, current_frame,
 188    current_gdbarch or deprecated_selected_frame) and instead refer to
 189    the FRAME or REGCACHE that has been passed into the containing
 190    function as parameters.  Consequently, the change typically
 191    involves modifying the containing function so that it takes a FRAME
 192    or REGCACHE parameter.  In the case of an architecture vector
 193    method, there should already be a non-deprecated variant that is
 194    parameterized with FRAME or REGCACHE.  */
 195
 196 extern char *deprecated_grub_regcache_for_registers (struct regcache *);
 197 extern char *deprecated_grub_regcache_for_register_valid (struct regcache *);
 198 extern void deprecated_read_register_gen (int regnum, char *myaddr);
 199 extern void deprecated_write_register_gen (int regnum, char *myaddr);
 200 extern void deprecated_read_register_bytes (int regbyte, char *myaddr,
 201                                             int len);
 202 extern void deprecated_write_register_bytes (int regbyte, char *myaddr,
 203                                              int len);
 204
 205 /* Character array containing the current state of each register
 206    (unavailable<0, invalid=0, valid>0) for the most recently
 207    referenced thread.  This global is often found in close proximity
 208    to code that is directly manipulating the deprecated_registers[]
 209    array.  In such cases, it should be possible to replace the lot
 210    with a call to supply_register().  If you find yourself in dire
 211    straits, still needing access to the cache status bit, the
 212    regcache_valid_p() and set_register_cached() functions are
 213    available.  */
 214 extern signed char *deprecated_register_valid;
 215
 216 /* Character array containing an image of the inferior programs'
 217    registers for the most recently referenced thread.
 218
 219    NOTE: cagney/2002-11-14: Target side code should be using
 220    supply_register() and/or regcache_collect() while architecture side
 221    code should use the more generic regcache methods.  */
 222
 223 extern char *deprecated_registers;
 224
 225 /* NOTE: cagney/2002-11-05: This function, and its co-conspirator
 226    deprecated_registers[], have been superseeded by supply_register().  */
 227 extern void deprecated_registers_fetched (void);
 228
 229 extern int register_cached (int regnum);
 230
 231 extern void set_register_cached (int regnum, int state);
 232
 233 extern void registers_changed (void);
 234
 235
 236 /* Rename to read_unsigned_register()? */
 237 extern ULONGEST read_register (int regnum);
 238
 239 /* Rename to read_unsigned_register_pid()? */
 240 extern ULONGEST read_register_pid (int regnum, ptid_t ptid);
 241
 242 extern LONGEST read_signed_register (int regnum);
 243
 244 extern LONGEST read_signed_register_pid (int regnum, ptid_t ptid);
 245
 246 extern void write_register (int regnum, LONGEST val);
 247
 248 extern void write_register_pid (int regnum, CORE_ADDR val, ptid_t ptid);
 249
 250 #endif /* REGCACHE_H */