gdbsupport/common-regcache.h

   1 /* Cache and manage the values of registers
   2
   3    Copyright (C) 2014-2020 Free Software Foundation, Inc.
   4
   5    This file is part of GDB.
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  19
  20 #ifndef COMMON_COMMON_REGCACHE_H
  21 #define COMMON_COMMON_REGCACHE_H
  22
  23 /* This header is a stopgap until we have an independent regcache.  */
  24
  25 enum register_status : signed char
  26   {
  27     /* The register value is not in the cache, and we don't know yet
  28        whether it's available in the target (or traceframe).  */
  29     REG_UNKNOWN = 0,
  30
  31     /* The register value is valid and cached.  */
  32     REG_VALID = 1,
  33
  34     /* The register value is unavailable.  E.g., we're inspecting a
  35        traceframe, and this register wasn't collected.  Note that this
  36        is different a different "unavailable" from saying the register
  37        does not exist in the target's architecture --- in that case,
  38        the target should have given us a target description that does
  39        not include the register in the first place.  */
  40     REG_UNAVAILABLE = -1
  41   };
  42
  43 /* Return a pointer to the register cache associated with the
  44    thread specified by PTID.  This function must be provided by
  45    the client.  */
  46
  47 extern struct regcache *get_thread_regcache_for_ptid (ptid_t ptid);
  48
  49 /* Return the size of register numbered N in REGCACHE.  This function
  50    must be provided by the client.  */
  51
  52 extern int regcache_register_size (const struct regcache *regcache, int n);
  53
  54 /* Read the PC register.  This function must be provided by the
  55    client.  */
  56
  57 extern CORE_ADDR regcache_read_pc (struct regcache *regcache);
  58
  59 /* Read the PC register.  If PC cannot be read, return 0.
  60    This is a wrapper around 'regcache_read_pc'.  */
  61
  62 extern CORE_ADDR regcache_read_pc_protected (regcache *regcache);
  63
  64 /* Read a raw register into a unsigned integer.  */
  65 extern enum register_status regcache_raw_read_unsigned
  66   (struct regcache *regcache, int regnum, ULONGEST *val);
  67
  68 ULONGEST regcache_raw_get_unsigned (struct regcache *regcache, int regnum);
  69
  70 struct reg_buffer_common
  71 {
  72   virtual ~reg_buffer_common () = default;
  73
  74   /* Get the availability status of the value of register REGNUM in this
  75      buffer.  */
  76   virtual register_status get_register_status (int regnum) const = 0;
  77
  78   /* Supply register REGNUM, whose contents are stored in BUF, to REGCACHE.  */
  79   virtual void raw_supply (int regnum, const void *buf) = 0;
  80
  81   /* Collect register REGNUM from REGCACHE and store its contents in BUF.  */
  82   virtual void raw_collect (int regnum, void *buf) const = 0;
  83
  84   /* Compare the contents of the register stored in the regcache (ignoring the
  85      first OFFSET bytes) to the contents of BUF (without any offset).  Returns
  86      true if the same.  */
  87   virtual bool raw_compare (int regnum, const void *buf, int offset) const = 0;
  88 };
  89
  90 #endif /* COMMON_COMMON_REGCACHE_H */