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Diffstat (limited to 'gdb/i386-linux-nat.c')
-rw-r--r--gdb/i386-linux-nat.c143
1 files changed, 88 insertions, 55 deletions
diff --git a/gdb/i386-linux-nat.c b/gdb/i386-linux-nat.c
index 7eb49ae..190979b 100644
--- a/gdb/i386-linux-nat.c
+++ b/gdb/i386-linux-nat.c
@@ -47,22 +47,6 @@
#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"
@@ -83,6 +67,14 @@
#define PTRACE_SETREGSET 0x4205
#endif
+/* Per-thread arch-specific data we want to keep. */
+
+struct arch_lwp_info
+{
+ /* Non-zero if our copy differs from what's recorded in the thread. */
+ int debug_registers_changed;
+};
+
/* Does the current host support PTRACE_GETREGSET? */
static int have_ptrace_getregset = -1;
@@ -651,8 +643,6 @@ i386_linux_store_inferior_registers (struct target_ops *ops,
/* Support for debug registers. */
-static unsigned long i386_linux_dr[DR_CONTROL + 1];
-
/* Get debug register REGNUM value from only the one LWP of PTID. */
static unsigned long
@@ -692,74 +682,116 @@ i386_linux_dr_set (ptid_t ptid, int regnum, unsigned long value)
perror_with_name (_("Couldn't write debug register"));
}
-/* Set DR_CONTROL to ADDR in all LWPs of LWP_LIST. */
+/* Return the inferior's debug register REGNUM. */
-static void
-i386_linux_dr_set_control (unsigned long control)
+static CORE_ADDR
+i386_linux_dr_get_addr (int regnum)
{
- struct lwp_info *lp;
+ /* DR6 and DR7 are retrieved with some other way. */
+ gdb_assert (DR_FIRSTADDR <= regnum && regnum <= DR_LASTADDR);
- i386_linux_dr[DR_CONTROL] = control;
- ALL_LWPS (lp)
- i386_linux_dr_set (lp->ptid, DR_CONTROL, control);
+ return i386_linux_dr_get (inferior_ptid, regnum);
}
-/* Set address REGNUM (zero based) to ADDR in all LWPs of LWP_LIST. */
+/* Return the inferior's DR7 debug control register. */
-static void
-i386_linux_dr_set_addr (int regnum, CORE_ADDR addr)
+static unsigned long
+i386_linux_dr_get_control (void)
{
- struct lwp_info *lp;
+ return i386_linux_dr_get (inferior_ptid, DR_CONTROL);
+}
- gdb_assert (regnum >= 0 && regnum <= DR_LASTADDR - DR_FIRSTADDR);
+/* Get DR_STATUS from only the one LWP of INFERIOR_PTID. */
- i386_linux_dr[DR_FIRSTADDR + regnum] = addr;
- ALL_LWPS (lp)
- i386_linux_dr_set (lp->ptid, DR_FIRSTADDR + regnum, addr);
+static unsigned long
+i386_linux_dr_get_status (void)
+{
+ return i386_linux_dr_get (inferior_ptid, DR_STATUS);
}
-/* Set address REGNUM (zero based) to zero in all LWPs of LWP_LIST. */
+/* Callback for iterate_over_lwps. Update the debug registers of
+ LWP. */
+
+static int
+update_debug_registers_callback (struct lwp_info *lwp, void *arg)
+{
+ /* The actual update is done later just before resuming the lwp, we
+ just mark that the registers need updating. */
+ lwp->arch_private->debug_registers_changed = 1;
+
+ /* If the lwp isn't stopped, force it to momentarily pause, so we
+ can update its debug registers. */
+ if (!lwp->stopped)
+ linux_stop_lwp (lwp);
+
+ return 0;
+}
+
+/* Set DR_CONTROL to ADDR in all LWPs of the current inferior. */
static void
-i386_linux_dr_reset_addr (int regnum)
+i386_linux_dr_set_control (unsigned long control)
{
- i386_linux_dr_set_addr (regnum, 0);
+ ptid_t pid_ptid = pid_to_ptid (ptid_get_pid (inferior_ptid));
+
+ iterate_over_lwps (pid_ptid, update_debug_registers_callback, NULL);
}
-/* Get DR_STATUS from only the one LWP of INFERIOR_PTID. */
+/* Set address REGNUM (zero based) to ADDR in all LWPs of the current
+ inferior. */
-static unsigned long
-i386_linux_dr_get_status (void)
+static void
+i386_linux_dr_set_addr (int regnum, CORE_ADDR addr)
{
- return i386_linux_dr_get (inferior_ptid, DR_STATUS);
+ ptid_t pid_ptid = pid_to_ptid (ptid_get_pid (inferior_ptid));
+
+ gdb_assert (regnum >= 0 && regnum <= DR_LASTADDR - DR_FIRSTADDR);
+
+ iterate_over_lwps (pid_ptid, update_debug_registers_callback, NULL);
}
-/* Unset MASK bits in DR_STATUS in all LWPs of LWP_LIST. */
+/* Called when resuming a thread.
+ If the debug regs have changed, update the thread's copies. */
static void
-i386_linux_dr_unset_status (unsigned long mask)
+i386_linux_prepare_to_resume (struct lwp_info *lwp)
{
- struct lwp_info *lp;
+ int clear_status = 0;
- ALL_LWPS (lp)
+ if (lwp->arch_private->debug_registers_changed)
{
- unsigned long value;
+ struct i386_debug_reg_state *state = i386_debug_reg_state ();
+ int i;
+
+ for (i = DR_FIRSTADDR; i <= DR_LASTADDR; i++)
+ if (state->dr_ref_count[i] > 0)
+ {
+ i386_linux_dr_set (lwp->ptid, i, state->dr_mirror[i]);
+
+ /* If we're setting a watchpoint, any change the inferior
+ had done itself to the debug registers needs to be
+ discarded, otherwise, i386_stopped_data_address can get
+ confused. */
+ clear_status = 1;
+ }
- value = i386_linux_dr_get (lp->ptid, DR_STATUS);
- value &= ~mask;
- i386_linux_dr_set (lp->ptid, DR_STATUS, value);
+ i386_linux_dr_set (lwp->ptid, DR_CONTROL, state->dr_control_mirror);
+
+ lwp->arch_private->debug_registers_changed = 0;
}
+
+ if (clear_status || lwp->stopped_by_watchpoint)
+ i386_linux_dr_set (lwp->ptid, DR_STATUS, 0);
}
static void
-i386_linux_new_thread (ptid_t ptid)
+i386_linux_new_thread (struct lwp_info *lp)
{
- int i;
+ struct arch_lwp_info *info = XCNEW (struct arch_lwp_info);
- for (i = DR_FIRSTADDR; i <= DR_LASTADDR; i++)
- i386_linux_dr_set (ptid, i, i386_linux_dr[i]);
+ info->debug_registers_changed = 1;
- i386_linux_dr_set (ptid, DR_CONTROL, i386_linux_dr[DR_CONTROL]);
+ lp->arch_private = info;
}
@@ -978,9 +1010,9 @@ _initialize_i386_linux_nat (void)
i386_dr_low.set_control = i386_linux_dr_set_control;
i386_dr_low.set_addr = i386_linux_dr_set_addr;
- i386_dr_low.reset_addr = i386_linux_dr_reset_addr;
+ i386_dr_low.get_addr = i386_linux_dr_get_addr;
i386_dr_low.get_status = i386_linux_dr_get_status;
- i386_dr_low.unset_status = i386_linux_dr_unset_status;
+ i386_dr_low.get_control = i386_linux_dr_get_control;
i386_set_debug_register_length (4);
/* Override the default ptrace resume method. */
@@ -999,4 +1031,5 @@ _initialize_i386_linux_nat (void)
/* Register the target. */
linux_nat_add_target (t);
linux_nat_set_new_thread (t, i386_linux_new_thread);
+ linux_nat_set_prepare_to_resume (t, i386_linux_prepare_to_resume);
}