28e7fd6234
Two modifications: 1. The addition of 2013 to the copyright year range for every file; 2. The use of a single year range, instead of potentially multiple year ranges, as approved by the FSF.
117 lines
4.6 KiB
C
117 lines
4.6 KiB
C
/* Misc. low level support for i386.
|
||
|
||
Copyright (C) 2009-2013 Free Software Foundation, Inc.
|
||
|
||
This file is part of GDB.
|
||
|
||
This program is free software; you can redistribute it and/or modify
|
||
it under the terms of the GNU General Public License as published by
|
||
the Free Software Foundation; either version 3 of the License, or
|
||
(at your option) any later version.
|
||
|
||
This program is distributed in the hope that it will be useful,
|
||
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
||
GNU General Public License for more details.
|
||
|
||
You should have received a copy of the GNU General Public License
|
||
along with this program. If not, see <http://www.gnu.org/licenses/>. */
|
||
|
||
/* Support for hardware watchpoints and breakpoints using the i386
|
||
debug registers.
|
||
|
||
This provides several functions for inserting and removing
|
||
hardware-assisted breakpoints and watchpoints, testing if one or
|
||
more of the watchpoints triggered and at what address, checking
|
||
whether a given region can be watched, etc.
|
||
|
||
The functions below implement debug registers sharing by reference
|
||
counts, and allow to watch regions up to 16 bytes long
|
||
(32 bytes on 64 bit hosts). */
|
||
|
||
|
||
/* Debug registers' indices. */
|
||
#define DR_FIRSTADDR 0
|
||
#define DR_LASTADDR 3
|
||
#define DR_NADDR 4 /* The number of debug address registers. */
|
||
#define DR_STATUS 6
|
||
#define DR_CONTROL 7
|
||
|
||
/* Global state needed to track h/w watchpoints. */
|
||
|
||
struct i386_debug_reg_state
|
||
{
|
||
/* Mirror the inferior's DRi registers. We keep the status and
|
||
control registers separated because they don't hold addresses.
|
||
Note that since we can change these mirrors while threads are
|
||
running, we never trust them to explain a cause of a trap.
|
||
For that, we need to peek directly in the inferior registers. */
|
||
CORE_ADDR dr_mirror[DR_NADDR];
|
||
unsigned dr_status_mirror, dr_control_mirror;
|
||
|
||
/* Reference counts for each debug register. */
|
||
int dr_ref_count[DR_NADDR];
|
||
};
|
||
|
||
/* Initialize STATE. */
|
||
extern void i386_low_init_dregs (struct i386_debug_reg_state *state);
|
||
|
||
/* Insert a watchpoint to watch a memory region which starts at
|
||
address ADDR and whose length is LEN bytes. Watch memory accesses
|
||
of the type TYPE_FROM_PACKET. Return 0 on success, -1 on failure. */
|
||
extern int i386_low_insert_watchpoint (struct i386_debug_reg_state *state,
|
||
char type_from_packet, CORE_ADDR addr,
|
||
int len);
|
||
|
||
/* Remove a watchpoint that watched the memory region which starts at
|
||
address ADDR, whose length is LEN bytes, and for accesses of the
|
||
type TYPE_FROM_PACKET. Return 0 on success, -1 on failure. */
|
||
extern int i386_low_remove_watchpoint (struct i386_debug_reg_state *state,
|
||
char type_from_packet, CORE_ADDR addr,
|
||
int len);
|
||
|
||
/* Return non-zero if we can watch a memory region that starts at
|
||
address ADDR and whose length is LEN bytes. */
|
||
extern int i386_low_region_ok_for_watchpoint (struct i386_debug_reg_state *state,
|
||
CORE_ADDR addr, int len);
|
||
|
||
/* If the inferior has some break/watchpoint that triggered, set the
|
||
address associated with that break/watchpoint and return true.
|
||
Otherwise, return false. */
|
||
extern int i386_low_stopped_data_address (struct i386_debug_reg_state *state,
|
||
CORE_ADDR *addr_p);
|
||
|
||
/* Return true if the inferior has some watchpoint that triggered.
|
||
Otherwise return false. */
|
||
extern int i386_low_stopped_by_watchpoint (struct i386_debug_reg_state *state);
|
||
|
||
/* Each target needs to provide several low-level functions
|
||
that will be called to insert watchpoints and hardware breakpoints
|
||
into the inferior, remove them, and check their status. These
|
||
functions are:
|
||
|
||
i386_dr_low_set_control -- set the debug control (DR7)
|
||
register to a given value
|
||
|
||
i386_dr_low_set_addr -- put an address into one debug register
|
||
|
||
i386_dr_low_get_status -- return the value of the debug
|
||
status (DR6) register.
|
||
*/
|
||
|
||
/* Update the inferior's debug register REGNUM from STATE. */
|
||
extern void i386_dr_low_set_addr (const struct i386_debug_reg_state *state,
|
||
int regnum);
|
||
|
||
/* Return the inferior's debug register REGNUM. */
|
||
extern CORE_ADDR i386_dr_low_get_addr (int regnum);
|
||
|
||
/* Update the inferior's DR7 debug control register from STATE. */
|
||
extern void i386_dr_low_set_control (const struct i386_debug_reg_state *state);
|
||
|
||
/* Return the value of the inferior's DR7 debug control register. */
|
||
extern unsigned i386_dr_low_get_control (void);
|
||
|
||
/* Return the value of the inferior's DR6 debug status register. */
|
||
extern unsigned i386_dr_low_get_status (void);
|