Move gdbserver to top level

This patch moves gdbserver to the top level.

This patch is as close to a pure move as possible -- gdbserver still
builds its own variant of gnulib and gdbsupport.  Changing this will
be done in a separate patch.

[v2] Note that, per Simon's review comment, this patch changes the
tree so that gdbserver is not built for or1k or score.  This makes
sense, because there is apparently not actually a gdbserver port here.

[v3] This version of the patch also splits out some configury into a
new file, gdbserver/configure.host, so that the top-level configure
script can simply rely on it in order to decide whether gdbserver
should be built.

[v4] This version adds documentation and removes some unnecessary
top-level dependencies.

[v5] Update docs to mention "make all-gdbserver" and change how
top-level configure decides whether to build gdbserver, switching to a
single, shared script.

Tested by the buildbot.

ChangeLog
2020-02-07  Tom Tromey  <tom@tromey.com>
	    Pedro Alves  <palves@redhat.com>

	* src-release.sh (GDB_SUPPORT_DIRS): Add gdbserver.
	* gdbserver: New directory, moved from gdb/gdbserver.
	* configure.ac (host_tools): Add gdbserver.
	Only build gdbserver on certain systems.
	* Makefile.in, configure: Rebuild.
	* Makefile.def (host_modules, dependencies): Add gdbserver.
	* MAINTAINERS: Add gdbserver.

gdb/ChangeLog
2020-02-07  Tom Tromey  <tom@tromey.com>

	* README: Update gdbserver documentation.
	* gdbserver: Move to top level.
	* configure.tgt (build_gdbserver): Remove.
	* configure.ac: Remove --enable-gdbserver.
	* configure: Rebuild.
	* Makefile.in (distclean): Don't mention gdbserver.

Change-Id: I826b7565b54604711dc7a11edea0499cd51ff39e

1 files changed, 0 insertions, 315 deletions

diff --git a/gdb/gdbserver/linux-xtensa-low.c b/gdb/gdbserver/linux-xtensa-low.c
deleted file mode 100644
index 83af11e..0000000
--- a/gdb/gdbserver/linux-xtensa-low.c
+++ /dev/null
@@ -1,315 +0,0 @@
-/* GNU/Linux/Xtensa specific low level interface, for the remote server for GDB.
-   Copyright (C) 2007-2020 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/>.  */
-
-
-#include "server.h"
-#include "linux-low.h"
-
-/* Defined in auto-generated file reg-xtensa.c.  */
-void init_registers_xtensa (void);
-extern const struct target_desc *tdesc_xtensa;
-
-#include <asm/ptrace.h>
-#include <xtensa-config.h>
-#include "arch/xtensa.h"
-#include "gdb_proc_service.h"
-
-#include "xtensa-xtregs.c"
-
-enum regnum {
-	R_PC=0,	R_PS,
-	R_LBEG,	R_LEND,	R_LCOUNT,
-	R_SAR,
-	R_WS, R_WB,
-	R_THREADPTR,
-	R_A0 = 64
-};
-
-static void
-xtensa_fill_gregset (struct regcache *regcache, void *buf)
-{
-  elf_greg_t* rset = (elf_greg_t*)buf;
-  const struct target_desc *tdesc = regcache->tdesc;
-  int ar0_regnum;
-  char *ptr;
-  int i;
-
-  /* Take care of AR registers.  */
-
-  ar0_regnum = find_regno (tdesc, "ar0");
-  ptr = (char*)&rset[R_A0];
-
-  for (i = ar0_regnum; i < ar0_regnum + XCHAL_NUM_AREGS; i++)
-    {
-      collect_register (regcache, i, ptr);
-      ptr += register_size (tdesc, i);
-    }
-
-  if (XSHAL_ABI == XTHAL_ABI_CALL0)
-    {
-      int a0_regnum = find_regno (tdesc, "a0");
-      ptr = (char *) &rset[R_A0 + 4 * rset[R_WB]];
-
-      for (i = a0_regnum; i < a0_regnum + C0_NREGS; i++)
-	{
-	  if ((4 * rset[R_WB] + i - a0_regnum) == XCHAL_NUM_AREGS)
-	    ptr = (char *) &rset[R_A0];
-	  collect_register (regcache, i, ptr);
-	  ptr += register_size (tdesc, i);
-	}
-    }
-
-  /* Loop registers, if hardware has it.  */
-
-#if XCHAL_HAVE_LOOPS
-  collect_register_by_name (regcache, "lbeg", (char*)&rset[R_LBEG]);
-  collect_register_by_name (regcache, "lend", (char*)&rset[R_LEND]);
-  collect_register_by_name (regcache, "lcount", (char*)&rset[R_LCOUNT]);
-#endif
-
-  collect_register_by_name (regcache, "sar", (char*)&rset[R_SAR]);
-  collect_register_by_name (regcache, "pc", (char*)&rset[R_PC]);
-  collect_register_by_name (regcache, "ps", (char*)&rset[R_PS]);
-  collect_register_by_name (regcache, "windowbase", (char*)&rset[R_WB]);
-  collect_register_by_name (regcache, "windowstart", (char*)&rset[R_WS]);
-
-#if XCHAL_HAVE_THREADPTR
-  collect_register_by_name (regcache, "threadptr",
-			    (char *) &rset[R_THREADPTR]);
-#endif
-}
-
-static void
-xtensa_store_gregset (struct regcache *regcache, const void *buf)
-{
-  const elf_greg_t* rset = (const elf_greg_t*)buf;
-  const struct target_desc *tdesc = regcache->tdesc;
-  int ar0_regnum;
-  char *ptr;
-  int i;
-
-  /* Take care of AR registers.  */
-
-  ar0_regnum = find_regno (tdesc, "ar0");
-  ptr = (char *)&rset[R_A0];
-
-  for (i = ar0_regnum; i < ar0_regnum + XCHAL_NUM_AREGS; i++)
-    {
-      supply_register (regcache, i, ptr);
-      ptr += register_size (tdesc, i);
-    }
-
-  if (XSHAL_ABI == XTHAL_ABI_CALL0)
-    {
-      int a0_regnum = find_regno (tdesc, "a0");
-      ptr = (char *) &rset[R_A0 + (4 * rset[R_WB]) % XCHAL_NUM_AREGS];
-
-      for (i = a0_regnum; i < a0_regnum + C0_NREGS; i++)
-	{
-	  if ((4 * rset[R_WB] + i - a0_regnum) == XCHAL_NUM_AREGS)
-	    ptr = (char *) &rset[R_A0];
-	  supply_register (regcache, i, ptr);
-	  ptr += register_size (tdesc, i);
-	}
-    }
-
-  /* Loop registers, if hardware has it.  */
-
-#if XCHAL_HAVE_LOOPS
-  supply_register_by_name (regcache, "lbeg", (char*)&rset[R_LBEG]);
-  supply_register_by_name (regcache, "lend", (char*)&rset[R_LEND]);
-  supply_register_by_name (regcache, "lcount", (char*)&rset[R_LCOUNT]);
-#endif
-
-  supply_register_by_name (regcache, "sar", (char*)&rset[R_SAR]);
-  supply_register_by_name (regcache, "pc", (char*)&rset[R_PC]);
-  supply_register_by_name (regcache, "ps", (char*)&rset[R_PS]);
-  supply_register_by_name (regcache, "windowbase", (char*)&rset[R_WB]);
-  supply_register_by_name (regcache, "windowstart", (char*)&rset[R_WS]);
-
-#if XCHAL_HAVE_THREADPTR
-  supply_register_by_name (regcache, "threadptr",
-			   (char *) &rset[R_THREADPTR]);
-#endif
-}
-
-/* Xtensa GNU/Linux PTRACE interface includes extended register set.  */
-
-static void
-xtensa_fill_xtregset (struct regcache *regcache, void *buf)
-{
-  const xtensa_regtable_t *ptr;
-
-  for (ptr = xtensa_regmap_table; ptr->name; ptr++)
-    {
-      collect_register_by_name (regcache, ptr->name,
-				(char*)buf + ptr->ptrace_offset);
-    }
-}
-
-static void
-xtensa_store_xtregset (struct regcache *regcache, const void *buf)
-{
-  const xtensa_regtable_t *ptr;
-
-  for (ptr = xtensa_regmap_table; ptr->name; ptr++)
-    {
-      supply_register_by_name (regcache, ptr->name,
-				(char*)buf + ptr->ptrace_offset);
-    }
-}
-
-static struct regset_info xtensa_regsets[] = {
-  { PTRACE_GETREGS, PTRACE_SETREGS, 0, sizeof (elf_gregset_t),
-    GENERAL_REGS,
-    xtensa_fill_gregset, xtensa_store_gregset },
-  { PTRACE_GETXTREGS, PTRACE_SETXTREGS, 0, XTENSA_ELF_XTREG_SIZE,
-    EXTENDED_REGS,
-    xtensa_fill_xtregset, xtensa_store_xtregset },
-  NULL_REGSET
-};
-
-#if XCHAL_HAVE_BE
-#define XTENSA_BREAKPOINT {0xd2,0x0f}
-#else
-#define XTENSA_BREAKPOINT {0x2d,0xf0}
-#endif
-
-static const gdb_byte xtensa_breakpoint[] = XTENSA_BREAKPOINT;
-#define xtensa_breakpoint_len 2
-
-/* Implementation of linux_target_ops method "sw_breakpoint_from_kind".  */
-
-static const gdb_byte *
-xtensa_sw_breakpoint_from_kind (int kind, int *size)
-{
-  *size = xtensa_breakpoint_len;
-  return xtensa_breakpoint;
-}
-
-static int
-xtensa_breakpoint_at (CORE_ADDR where)
-{
-    unsigned long insn;
-
-    (*the_target->read_memory) (where, (unsigned char *) &insn,
-				xtensa_breakpoint_len);
-    return memcmp((char *) &insn,
-		  xtensa_breakpoint, xtensa_breakpoint_len) == 0;
-}
-
-/* Called by libthread_db.  */
-
-ps_err_e
-ps_get_thread_area (struct ps_prochandle *ph,
-                    lwpid_t lwpid, int idx, void **base)
-{
-  xtensa_elf_gregset_t regs;
-
-  if (ptrace (PTRACE_GETREGS, lwpid, NULL, &regs) != 0)
-    return PS_ERR;
-
-  /* IDX is the bias from the thread pointer to the beginning of the
-     thread descriptor.  It has to be subtracted due to implementation
-     quirks in libthread_db.  */
-  *base = (void *) ((char *) regs.threadptr - idx);
-
-  return PS_OK;
-}
-
-static struct regsets_info xtensa_regsets_info =
-  {
-    xtensa_regsets, /* regsets */
-    0, /* num_regsets */
-    NULL, /* disabled_regsets */
-  };
-
-static struct regs_info regs_info =
-  {
-    NULL, /* regset_bitmap */
-    NULL, /* usrregs */
-    &xtensa_regsets_info
-  };
-
-static void
-xtensa_arch_setup (void)
-{
-  current_process ()->tdesc = tdesc_xtensa;
-}
-
-/* Support for hardware single step.  */
-
-static int
-xtensa_supports_hardware_single_step (void)
-{
-  return 1;
-}
-
-static const struct regs_info *
-xtensa_regs_info (void)
-{
-  return &regs_info;
-}
-
-struct linux_target_ops the_low_target = {
-  xtensa_arch_setup,
-  xtensa_regs_info,
-  0,
-  0,
-  NULL, /* fetch_register */
-  linux_get_pc_32bit,
-  linux_set_pc_32bit,
-  NULL, /* breakpoint_kind_from_pc */
-  xtensa_sw_breakpoint_from_kind,
-  NULL,
-  0,
-  xtensa_breakpoint_at,
-  NULL, /* supports_z_point_type */
-  NULL, /* insert_point */
-  NULL, /* remove_point */
-  NULL, /* stopped_by_watchpoint */
-  NULL, /* stopped_data_address */
-  NULL, /* collect_ptrace_register */
-  NULL, /* supply_ptrace_register */
-  NULL, /* siginfo_fixup */
-  NULL, /* new_process */
-  NULL, /* delete_process */
-  NULL, /* new_thread */
-  NULL, /* delete_thread */
-  NULL, /* new_fork */
-  NULL, /* prepare_to_resume */
-  NULL, /* process_qsupported */
-  NULL, /* supports_tracepoints */
-  NULL, /* get_thread_area */
-  NULL, /* install_fast_tracepoint_jump_pad */
-  NULL, /* emit_ops */
-  NULL, /* get_min_fast_tracepoint_insn_len */
-  NULL, /* supports_range_stepping */
-  NULL, /* breakpoint_kind_from_current_state */
-  xtensa_supports_hardware_single_step,
-};
-
-
-void
-initialize_low_arch (void)
-{
-  /* Initialize the Linux target descriptions.  */
-  init_registers_xtensa ();
-
-  initialize_regsets_info (&xtensa_regsets_info);
-}