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, 56 insertions, 0 deletions

diff --git a/gdbserver/linux-x86-tdesc.h b/gdbserver/linux-x86-tdesc.h
new file mode 100644
index 0000000..21c8dfd
--- /dev/null
+++ b/gdbserver/linux-x86-tdesc.h
@@ -0,0 +1,56 @@
+/* Low level support for x86 (i386 and x86-64), shared between gdbserver
+   and IPA.
+
+   Copyright (C) 2016-2020 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/>.  */
+
+#ifndef GDBSERVER_LINUX_X86_TDESC_H
+#define GDBSERVER_LINUX_X86_TDESC_H
+
+/* Note: since IPA obviously knows what ABI it's running on (i386 vs x86_64
+   vs x32), it's sufficient to pass only the register set here.  This,
+   together with the ABI known at IPA compile time, maps to a tdesc.  */
+
+enum x86_linux_tdesc {
+  X86_TDESC_MMX = 0,
+  X86_TDESC_SSE = 1,
+  X86_TDESC_AVX = 2,
+  X86_TDESC_MPX = 3,
+  X86_TDESC_AVX_MPX = 4,
+  X86_TDESC_AVX_AVX512 = 5,
+  X86_TDESC_AVX_MPX_AVX512_PKU = 6,
+  X86_TDESC_LAST = 7,
+};
+
+#if defined __i386__ || !defined IN_PROCESS_AGENT
+int i386_get_ipa_tdesc_idx (const struct target_desc *tdesc);
+#endif
+
+#if defined __x86_64__ && !defined IN_PROCESS_AGENT
+int amd64_get_ipa_tdesc_idx (const struct target_desc *tdesc);
+#endif
+
+const struct target_desc *i386_get_ipa_tdesc (int idx);
+
+#ifdef __x86_64__
+const struct target_desc *amd64_linux_read_description (uint64_t xcr0,
+							bool is_x32);
+#endif
+
+const struct target_desc *i386_linux_read_description (uint64_t xcr0);
+
+#endif /* GDBSERVER_LINUX_X86_TDESC_H */