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[PATCH]: Make Linux use the new unified x86 watchpoint support
- To: gdb-patches at sources dot redhat dot com
- Subject: [PATCH]: Make Linux use the new unified x86 watchpoint support
- From: Mark Kettenis <kettenis at wins dot uva dot nl>
- Date: Wed, 21 Mar 2001 22:23:30 +0100
FYI, I checked this in. HJ can finally be happy now (although things
probably won't work correctly for multithreaded programs).
Mark
Index: ChangeLog
from Mark Kettenis <kettenis@gnu.org>
Make Linux use the new unified support for hardware breakpoints
and watchpoints on x86 targets.
* i386-linux-nat.c: Doc fixes. Include "gdb_assert.h".
[HAVE_SYS_DEBUGREG_H]: Include <sys/debugreg.h>.
(DR_FIRSTADDR, DR_LASTADDR, DR_STATUS, DR_CONTROL): Define to
appropriate value if not already defined.
(register_u_addr): New function.
(kernel_u_size): New function.
(i386_linux_dr_get, i386_linux_dr_set): New functions.
(i386_linux_dr_set_control, i386_linux_dr_set_addr,
i386_linux_reset_addr, i386_linux_dr_get_status): New functions.
* config/i386/nm-linux.h: Don't include "nm-i386v.h".
(I386_USE_GENERIC_WATCHPOINTS): Define and include "nm-i386.h".
(TARGET_HAS_HARDWARE_WATCHPOINTS,
TARGET_CAN_USE_HARDWARE_WATCHPOINTS, HAVE_CONTINUABLE_WATCHPOINT,
STOPPED_BY_WATCHPOINT, target_insert_watchpoint,
target_remove_watchpoint): Remove macros.
(i386_stopped_by_watchpoint, i386_insert_watchpoint,
i386_remove_watchpoint): Remove prototypes.
(register_u_addr): New prototype.
(REGISTER_U_ADDR): Define in terms of register_u_addr.
(i386_linux_dr_set_control, i386_linux_dr_set_addr,
i386_linux_reset_addr, i386_linux_dr_get_status): New prototypes.
(I386_DR_LOW_SET_CONTROL, I386_DR_LOW_SET_ADDR,
I386_DR_LOW_RESET_ADDR, I386_DR_LOW_GET_STATUS): New macros.
* config/i386/linux.mh (NATDEPFILES): Replace i386v-nat.o with
i386-nat.o.
Index: i386-linux-nat.c
===================================================================
RCS file: /cvs/src/src/gdb/i386-linux-nat.c,v
retrieving revision 1.23
diff -u -p -r1.23 i386-linux-nat.c
--- i386-linux-nat.c 2001/03/13 23:31:13 1.23
+++ i386-linux-nat.c 2001/03/21 21:20:21
@@ -23,6 +23,7 @@
#include "gdbcore.h"
#include "regcache.h"
+#include "gdb_assert.h"
#include <sys/ptrace.h>
#include <sys/user.h>
#include <sys/procfs.h>
@@ -31,6 +32,26 @@
#include <sys/reg.h>
#endif
+#ifdef HAVE_SYS_DEBUGREG_H
+#include <sys/debugreg.h>
+#endif
+
+#ifndef DR_FIRSTADDR
+#define DR_FIRSTADDR 0
+#endif
+
+#ifndef DR_LASTADDR
+#define DR_LASTADDR 3
+#endif
+
+#ifndef DR_STATUS
+#define DR_STATUS 6
+#endif
+
+#ifndef DR_CONTROL
+#define DR_CONTROL 7
+#endif
+
/* Prototypes for supply_gregset etc. */
#include "gregset.h"
@@ -110,6 +131,26 @@ int have_ptrace_getfpxregs =
;
+/* Support for the user struct. */
+
+/* Return the address of register REGNUM. BLOCKEND is the value of
+ u.u_ar0, which should point to the registers. */
+
+CORE_ADDR
+register_u_addr (CORE_ADDR blockend, int regnum)
+{
+ return (blockend + 4 * regmap[regnum]);
+}
+
+/* Return the size of the user struct. */
+
+int
+kernel_u_size (void)
+{
+ return (sizeof (struct user));
+}
+
+
/* Fetching registers directly from the U area, one at a time. */
/* FIXME: kettenis/2000-03-05: This duplicates code from `inptrace.c'.
@@ -657,6 +698,72 @@ store_inferior_registers (int regno)
internal_error (__FILE__, __LINE__,
"Got request to store bad register number %d.", regno);
+}
+
+
+static long
+i386_linux_dr_get (int regnum)
+{
+ int tid;
+ long value;
+
+ /* FIXME: kettenis/2001-01-29: It's not clear what we should do with
+ multi-threaded processes here. For now, pretend there is just
+ one thread. */
+ tid = PIDGET (inferior_pid);
+
+ errno = 0;
+ value = ptrace (PT_READ_U, tid,
+ offsetof (struct user, u_debugreg[regnum]), 0);
+ if (errno != 0)
+ perror_with_name ("Couldn't read debug register");
+
+ return value;
+}
+
+static void
+i386_linux_dr_set (int regnum, long value)
+{
+ int tid;
+
+ /* FIXME: kettenis/2001-01-29: It's not clear what we should do with
+ multi-threaded processes here. For now, pretend there is just
+ one thread. */
+ tid = PIDGET (inferior_pid);
+
+ errno = 0;
+ ptrace (PT_WRITE_U, tid,
+ offsetof (struct user, u_debugreg[regnum]), value);
+ if (errno != 0)
+ perror_with_name ("Couldn't write debug register");
+}
+
+void
+i386_linux_dr_set_control (long control)
+{
+ i386_linux_dr_set (DR_CONTROL, control);
+}
+
+void
+i386_linux_dr_set_addr (int regnum, CORE_ADDR addr)
+{
+ gdb_assert (regnum >= 0 && regnum <= DR_LASTADDR - DR_FIRSTADDR);
+
+ i386_linux_dr_set (DR_FIRSTADDR + regnum, addr);
+}
+
+void
+i386_linux_dr_reset_addr (int regnum)
+{
+ gdb_assert (regnum >= 0 && regnum <= DR_LASTADDR - DR_FIRSTADDR);
+
+ i386_linux_dr_set (DR_FIRSTADDR + regnum, 0L);
+}
+
+long
+i386_linux_dr_get_status (void)
+{
+ return i386_linux_dr_get (DR_STATUS);
}
Index: config/i386/nm-linux.h
===================================================================
RCS file: /cvs/src/src/gdb/config/i386/nm-linux.h,v
retrieving revision 1.8
diff -u -p -r1.8 nm-linux.h
--- config/i386/nm-linux.h 2001/03/06 08:21:28 1.8
+++ config/i386/nm-linux.h 2001/03/21 21:20:21
@@ -1,6 +1,6 @@
/* Native support for Linux/x86.
Copyright 1986, 1987, 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
- 1999, 2000
+ 1999, 2000, 2001
Free Software Foundation, Inc.
This file is part of GDB.
@@ -23,52 +23,56 @@
#ifndef NM_LINUX_H
#define NM_LINUX_H
-#include "i386/nm-i386v.h"
+/* GNU/Linux supports the i386 hardware debugging registers. */
+#define I386_USE_GENERIC_WATCHPOINTS
+
+#include "i386/nm-i386.h"
#include "nm-linux.h"
-/* Return sizeof user struct to callers in less machine dependent routines */
+/* Return sizeof user struct to callers in less machine dependent
+ routines. */
-#define KERNEL_U_SIZE kernel_u_size()
extern int kernel_u_size (void);
+#define KERNEL_U_SIZE kernel_u_size()
#define U_REGS_OFFSET 0
-
-/* GNU/Linux supports the 386 hardware debugging registers. */
-
-#define TARGET_HAS_HARDWARE_WATCHPOINTS
-
-#define TARGET_CAN_USE_HARDWARE_WATCHPOINT(type, cnt, ot) 1
-/* After a watchpoint trap, the PC points to the instruction after
- the one that caused the trap. Therefore we don't need to step over it.
- But we do need to reset the status register to avoid another trap. */
-#define HAVE_CONTINUABLE_WATCHPOINT
+extern CORE_ADDR register_u_addr (CORE_ADDR blockend, int regnum);
+#define REGISTER_U_ADDR(addr, blockend, regnum) \
+ (addr) = register_u_addr (blockend, regnum)
+
+/* Provide access to the i386 hardware debugging registers. */
+
+extern void i386_linux_dr_set_control (long control);
+#define I386_DR_LOW_SET_CONTROL(control) \
+ i386_linux_dr_set_control (control)
+
+extern void i386_linux_dr_set_addr (int regnum, CORE_ADDR addr);
+#define I386_DR_LOW_SET_ADDR(regnum, addr) \
+ i386_linux_dr_set_addr (regnum, addr)
+
+extern void i386_linux_dr_reset_addr (int regnum);
+#define I386_DR_LOW_RESET_ADDR(regnum) \
+ i386_linux_dr_reset_addr (regnum)
+
+extern long i386_linux_dr_get_status (void);
+#define I386_DR_LOW_GET_STATUS() \
+ i386_linux_dr_get_status ()
-#define STOPPED_BY_WATCHPOINT(W) \
- i386_stopped_by_watchpoint (inferior_pid)
+/* We define this if link.h is available, because with ELF we use SVR4
+ style shared libraries. */
-/* Use these macros for watchpoint insertion/removal. */
-
-#define target_insert_watchpoint(addr, len, type) \
- i386_insert_watchpoint (inferior_pid, addr, len, type)
-
-#define target_remove_watchpoint(addr, len, type) \
- i386_remove_watchpoint (inferior_pid, addr, len)
-
-/* We define this if link.h is available, because with ELF we use SVR4 style
- shared libraries. */
-
#ifdef HAVE_LINK_H
#define SVR4_SHARED_LIBS
-#include "solib.h" /* Support for shared libraries. */
+#include "solib.h" /* Support for shared libraries. */
#endif
/* Override copies of {fetch,store}_inferior_registers in `infptrace.c'. */
#define FETCH_INFERIOR_REGISTERS
-/* Nevertheless, define CANNOT_{FETCH,STORE}_REGISTER, because we might fall
- back on the code `infptrace.c' (well a copy of that code in
- `i386-linux-nat.c' for now) and we can access only the
+/* Nevertheless, define CANNOT_{FETCH,STORE}_REGISTER, because we
+ might fall back on the code `infptrace.c' (well a copy of that code
+ in `i386-linux-nat.c' for now) and we can access only the
general-purpose registers in that way. */
extern int cannot_fetch_register (int regno);
extern int cannot_store_register (int regno);
@@ -77,10 +81,6 @@ extern int cannot_store_register (int re
/* Override child_resume in `infptrace.c'. */
#define CHILD_RESUME
-
-extern CORE_ADDR i386_stopped_by_watchpoint (int);
-extern int i386_insert_watchpoint (int pid, CORE_ADDR addr, int len, int rw);
-extern int i386_remove_watchpoint (int pid, CORE_ADDR addr, int len);
/* FIXME: kettenis/2000-09-03: This should be moved to ../nm-linux.h
once we have converted all Linux targets to use the new threads
Index: config/i386/linux.mh
===================================================================
RCS file: /cvs/src/src/gdb/config/i386/linux.mh,v
retrieving revision 1.6
diff -u -p -r1.6 linux.mh
--- config/i386/linux.mh 2000/10/30 22:33:32 1.6
+++ config/i386/linux.mh 2001/03/21 21:20:21
@@ -5,7 +5,7 @@ XDEPFILES=
NAT_FILE= nm-linux.h
NATDEPFILES= infptrace.o inftarg.o fork-child.o corelow.o \
- core-aout.o i386v-nat.o i386-linux-nat.o i387-nat.o \
+ core-aout.o i386-nat.o i386-linux-nat.o i387-nat.o \
proc-service.o thread-db.o lin-lwp.o
LOADLIBES = -ldl -rdynamic