Add an x86_fbsd_nat_target mixin class for FreeBSD x86 native targets.

This class implements debug register support common between the i386
and amd64 native targets.

While here, remove #ifdef's for HAVE_PT_GETDBREGS in FreeBSD-specific
code.  The ptrace request has been present on FreeBSD x86
architectures since 4.0 (released in March 2000).  The last FreeBSD
release without this support is 3.5 released in June 2000.

gdb/amd64-fbsd-nat.c

@@ -29,26 +29,20 @@
 #include <sys/user.h>
 #include <machine/reg.h>
 
-#include "fbsd-nat.h"
 #include "amd64-tdep.h"
 #include "amd64-fbsd-tdep.h"
 #include "amd64-nat.h"
 #include "x86-nat.h"
 #include "gdbsupport/x86-xstate.h"
-#include "x86-bsd-nat.h"
+#include "x86-fbsd-nat.h"
 
-class amd64_fbsd_nat_target final
-  : public x86bsd_nat_target<fbsd_nat_target>
+class amd64_fbsd_nat_target final : public x86_fbsd_nat_target
 {
 public:
   void fetch_registers (struct regcache *, int) override;
   void store_registers (struct regcache *, int) override;
 
   const struct target_desc *read_description () override;
-
-#if defined(HAVE_PT_GETDBREGS)
-  bool supports_stopped_by_hw_breakpoint () override;
-#endif
 };
 
 static amd64_fbsd_nat_target the_amd64_fbsd_nat_target;
@@ -348,16 +342,6 @@ amd64_fbsd_nat_target::read_description ()
     return i386_target_description (X86_XSTATE_SSE_MASK, true);
 }
 
-#if defined(HAVE_PT_GETDBREGS)
-/* Implement the supports_stopped_by_hw_breakpoints method.  */
-
-bool
-amd64_fbsd_nat_target::supports_stopped_by_hw_breakpoint ()
-{
-  return true;
-}
-#endif
-
 void _initialize_amd64fbsd_nat ();
 void
 _initialize_amd64fbsd_nat ()

gdb/i386-fbsd-nat.c

@@ -27,16 +27,14 @@
 #include <sys/sysctl.h>
 #include <sys/user.h>
 
-#include "fbsd-nat.h"
 #include "i386-tdep.h"
 #include "i386-fbsd-tdep.h"
 #include "i387-tdep.h"
 #include "x86-nat.h"
 #include "gdbsupport/x86-xstate.h"
-#include "x86-bsd-nat.h"
+#include "x86-fbsd-nat.h"
 
-class i386_fbsd_nat_target final
-  : public x86bsd_nat_target<fbsd_nat_target>
+class i386_fbsd_nat_target final : public x86_fbsd_nat_target
 {
 public:
   void fetch_registers (struct regcache *, int) override;
@@ -45,10 +43,6 @@ public:
   const struct target_desc *read_description () override;
 
   void resume (ptid_t, int, enum gdb_signal) override;
-
-#if defined(HAVE_PT_GETDBREGS)
-  bool supports_stopped_by_hw_breakpoint () override;
-#endif
 };
 
 static i386_fbsd_nat_target the_i386_fbsd_nat_target;
@@ -361,16 +355,6 @@ i386_fbsd_nat_target::read_description ()
   return i386_target_description (X86_XSTATE_X87_MASK, true);
 }
 
-#if defined(HAVE_PT_GETDBREGS)
-/* Implement the supports_stopped_by_hw_breakpoints method.  */
-
-bool
-i386_fbsd_nat_target::supports_stopped_by_hw_breakpoint ()
-{
-  return true;
-}
-#endif
-
 void _initialize_i386fbsd_nat ();
 void
 _initialize_i386fbsd_nat ()

gdb/x86-fbsd-nat.h

@@ -0,0 +1,34 @@
+/* Native-dependent code for FreeBSD x86.
+
+   Copyright (C) 2022 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/>.  */
+
+#ifndef X86_FBSD_NAT_H
+#define X86_FBSD_NAT_H
+
+#include "fbsd-nat.h"
+#include "x86-bsd-nat.h"
+
+/* A prototype FreeBSD/x86 target.  */
+
+class x86_fbsd_nat_target : public x86bsd_nat_target<fbsd_nat_target>
+{
+  bool supports_stopped_by_hw_breakpoint () override
+  { return true; }
+};
+
+#endif /* x86-bsd-nat.h */