+/* Support for debug registers. */
+
+#ifdef HAVE_PT_GETDBREGS
+
+/* Not all versions of FreeBSD/i386 that support the debug registers
+ have this macro. */
+#ifndef DBREG_DRX
+#define DBREG_DRX(d, x) ((&d->dr0)[x])
+#endif
+
+static void
+i386bsd_dr_set (int regnum, unsigned int value)
+{
+ struct dbreg dbregs;
+
+ if (ptrace (PT_GETDBREGS, inferior_pid, (PTRACE_ARG3_TYPE) &dbregs, 0) == -1)
+ perror_with_name ("Couldn't get debug registers");
+
+ /* For some mysterious reason, some of the reserved bits in the
+ debug control register get set. Mask these off, otherwise the
+ ptrace call below will fail. */
+ dbregs.dr7 &= ~(0x0000fc00);
+
+ DBREG_DRX ((&dbregs), regnum) = value;
+
+ if (ptrace (PT_SETDBREGS, inferior_pid, (PTRACE_ARG3_TYPE) &dbregs, 0) == -1)
+ perror_with_name ("Couldn't write debug registers");
+}
+
+void
+i386bsd_dr_set_control (unsigned long control)
+{
+ i386bsd_dr_set (7, control);
+}
+
+void
+i386bsd_dr_set_addr (int regnum, CORE_ADDR addr)
+{
+ gdb_assert (regnum >= 0 && regnum <= 4);
+
+ i386bsd_dr_set (regnum, addr);
+}
+
+void
+i386bsd_dr_reset_addr (int regnum)
+{
+ gdb_assert (regnum >= 0 && regnum <= 4);
+
+ i386bsd_dr_set (regnum, 0);
+}
+
+unsigned long
+i386bsd_dr_get_status (void)
+{
+ struct dbreg dbregs;
+
+ /* FIXME: kettenis/2001-03-31: Calling perror_with_name if the
+ ptrace call fails breaks debugging remote targets. The correct
+ way to fix this is to add the hardware breakpoint and watchpoint
+ stuff to the target vectore. For now, just return zero if the
+ ptrace call fails. */
+ if (ptrace (PT_GETDBREGS, inferior_pid, (PTRACE_ARG3_TYPE) &dbregs, 0) == -1)
+#if 0
+ perror_with_name ("Couldn't read debug registers");
+#else
+ return 0;
+#endif
+
+ return dbregs.dr6;
+}
+
+#endif /* PT_GETDBREGS */
+\f
+