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 supply_register (int regnum, const void *val);
100 extern void regcache_collect (int regnum, void *buf);
101 extern void regcache_raw_supply (struct regcache *regcache,
102 				 int regnum, const void *buf);
103 extern void regcache_raw_collect (const struct regcache *regcache,
104 				  int regnum, void *buf);
105 
106 
107 /* The register's ``offset''.
108 
109    FIXME: cagney/2002-11-07: The frame_register() function, when
110    specifying the real location of a register, does so using that
111    registers offset in the register cache.  That offset is then used
112    by valops.c to determine the location of the register.  The code
113    should instead use the register's number and a location expression
114    to describe a value spread across multiple registers or memory.  */
115 
116 extern int register_offset_hack (struct gdbarch *gdbarch, int regnum);
117 
118 
119 /* The type of a register.  This function is slightly more efficient
120    then its gdbarch vector counterpart since it returns a precomputed
121    value stored in a table.
122 
123    NOTE: cagney/2002-08-17: The original macro was called
124    DEPRECATED_REGISTER_VIRTUAL_TYPE.  This was because the register
125    could have different raw and cooked (nee virtual) representations.
126    The CONVERTABLE methods being used to convert between the two
127    representations.  Current code does not do this.  Instead, the
128    first [0..NUM_REGS) registers are 1:1 raw:cooked, and the type
129    exactly describes the register's representation.  Consequently, the
130    ``virtual'' has been dropped.
131 
132    FIXME: cagney/2002-08-17: A number of architectures, including the
133    MIPS, are currently broken in this regard.  */
134 
135 extern struct type *register_type (struct gdbarch *gdbarch, int regnum);
136 
137 
138 /* Return the size of register REGNUM.  All registers should have only
139    one size.
140 
141    FIXME: cagney/2003-02-28:
142 
143    Unfortunately, thanks to some legacy architectures, this doesn't
144    hold.  A register's cooked (nee virtual) and raw size can differ
145    (see MIPS).  Such architectures should be using different register
146    numbers for the different sized views of identical registers.
147 
148    Anyway, the up-shot is that, until that mess is fixed, core code
149    can end up being very confused - should the RAW or VIRTUAL size be
150    used?  As a rule of thumb, use DEPRECATED_REGISTER_VIRTUAL_SIZE in
151    cooked code, but with the comment:
152 
153    OK: REGISTER_VIRTUAL_SIZE
154 
155    or just
156 
157    OK
158 
159    appended to the end of the line.  */
160 
161 extern int register_size (struct gdbarch *gdbarch, int regnum);
162 
163 
164 /* Save/restore a register cache.  The set of registers saved /
165    restored into the DST regcache determined by the save_reggroup /
166    restore_reggroup respectively.  COOKED_READ returns zero iff the
167    register's value can't be returned.  */
168 
169 typedef int (regcache_cooked_read_ftype) (void *src, int regnum, void *buf);
170 
171 extern void regcache_save (struct regcache *dst,
172 			   regcache_cooked_read_ftype *cooked_read,
173 			   void *src);
174 extern void regcache_restore (struct regcache *dst,
175 			      regcache_cooked_read_ftype *cooked_read,
176 			      void *src);
177 
178 /* Copy/duplicate the contents of a register cache.  By default, the
179    operation is pass-through.  Writes to DST and reads from SRC will
180    go through to the target.
181 
182    The ``cpy'' functions can not have overlapping SRC and DST buffers.
183 
184    ``no passthrough'' versions do not go through to the target.  They
185    only transfer values already in the cache.  */
186 
187 extern struct regcache *regcache_dup (struct regcache *regcache);
188 extern struct regcache *regcache_dup_no_passthrough (struct regcache *regcache);
189 extern void regcache_cpy (struct regcache *dest, struct regcache *src);
190 extern void regcache_cpy_no_passthrough (struct regcache *dest, struct regcache *src);
191 
192 /* NOTE: cagney/2002-11-02: The below have been superseded by the
193    regcache_cooked_*() functions found above, and the frame_*()
194    functions found in "frame.h".  Take care though, often more than a
195    simple substitution is required when updating the code.  The
196    change, as far as practical, should avoid adding references to
197    global variables (e.g., current_regcache, current_frame,
198    current_gdbarch or deprecated_selected_frame) and instead refer to
199    the FRAME or REGCACHE that has been passed into the containing
200    function as parameters.  Consequently, the change typically
201    involves modifying the containing function so that it takes a FRAME
202    or REGCACHE parameter.  In the case of an architecture vector
203    method, there should already be a non-deprecated variant that is
204    parameterized with FRAME or REGCACHE.  */
205 
206 extern char *deprecated_grub_regcache_for_registers (struct regcache *);
207 extern void deprecated_read_register_gen (int regnum, char *myaddr);
208 extern void deprecated_write_register_gen (int regnum, char *myaddr);
209 extern void deprecated_read_register_bytes (int regbyte, char *myaddr,
210 					    int len);
211 extern void deprecated_write_register_bytes (int regbyte, char *myaddr,
212 					     int len);
213 
214 /* Character array containing the current state of each register
215    (unavailable<0, invalid=0, valid>0) for the most recently
216    referenced thread.  This global is often found in close proximity
217    to code that is directly manipulating the deprecated_registers[]
218    array.  In such cases, it should be possible to replace the lot
219    with a call to supply_register().  If you find yourself in dire
220    straits, still needing access to the cache status bit, the
221    regcache_valid_p() and set_register_cached() functions are
222    available.  */
223 extern signed char *deprecated_register_valid;
224 
225 /* Character array containing an image of the inferior programs'
226    registers for the most recently referenced thread.
227 
228    NOTE: cagney/2002-11-14: Target side code should be using
229    supply_register() and/or regcache_collect() while architecture side
230    code should use the more generic regcache methods.  */
231 
232 extern char *deprecated_registers;
233 
234 /* NOTE: cagney/2002-11-05: This function, and its co-conspirator
235    deprecated_registers[], have been superseeded by supply_register().  */
236 extern void deprecated_registers_fetched (void);
237 
238 extern int register_cached (int regnum);
239 
240 extern void set_register_cached (int regnum, int state);
241 
242 extern void registers_changed (void);
243 
244 
245 /* Rename to read_unsigned_register()? */
246 extern ULONGEST read_register (int regnum);
247 
248 /* Rename to read_unsigned_register_pid()? */
249 extern ULONGEST read_register_pid (int regnum, ptid_t ptid);
250 
251 extern void write_register (int regnum, LONGEST val);
252 
253 extern void write_register_pid (int regnum, CORE_ADDR val, ptid_t ptid);
254 
255 #endif /* REGCACHE_H */
256