[PATCH v2] arc: Add 'set disassembler-options' support

[Shahab Vahedi <shahab.vahedi@gmail.com>]

From: Shahab Vahedi <shahab@synopsys.com>

Implement ARC target support for passing options to the disassembler
through the command interface. e.g.:

gdb> set disassembler-options cpu=hs38_linux ...

v2:
- break the long line in the test (arc_disassemble_test {}).

gdb/ChangeLog:

	* NEWS: Document 'set disassembler-options' support for the ARC
	target.
	* arc-tdep.c (arc_gdbarch_init): Set
	'gdbarch_valid_disassembler_options'.

gdb/doc/ChangeLog:

	* gdb.texinfo (Source and Machine Code): Document 'set
	disassembler-options' support for the ARC target.

gdb/testsuite/ChangeLog:

	* gdb.arch/arc-disassembler-options.exp: New test.
	* gdb.arch/arc-disassembler-options.s: New test source.
---
 gdb/NEWS                                      |  3 ++
 gdb/arc-tdep.c                                |  6 ++-
 gdb/doc/gdb.texinfo                           |  4 +-
 .../gdb.arch/arc-disassembler-options.exp     | 45 +++++++++++++++++++
 .../gdb.arch/arc-disassembler-options.s       | 21 +++++++++
 5 files changed, 75 insertions(+), 4 deletions(-)
 create mode 100644 gdb/testsuite/gdb.arch/arc-disassembler-options.exp
 create mode 100644 gdb/testsuite/gdb.arch/arc-disassembler-options.s

diff --git a/gdb/NEWS b/gdb/NEWS
index ab678acec8b..56743fc9aea 100644
--- a/gdb/NEWS
+++ b/gdb/NEWS
@@ -3,6 +3,9 @@
 
 *** Changes since GDB 10
 
+* The 'set disassembler-options' command now supports specifying options
+  for the ARC target.
+
 * GDB now supports general memory tagging functionality if the underlying
   architecture supports the proper primitives and hooks.  Currently this is
   enabled only for AArch64 MTE.
diff --git a/gdb/arc-tdep.c b/gdb/arc-tdep.c
index ece802545c0..3afbf4264fe 100644
--- a/gdb/arc-tdep.c
+++ b/gdb/arc-tdep.c
@@ -2434,11 +2434,13 @@ arc_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches)
 	      arc_disassembler_options = NULL;
 	      break;
 	    }
-	  set_gdbarch_disassembler_options (gdbarch,
-					    &arc_disassembler_options);
 	}
     }
 
+  set_gdbarch_disassembler_options (gdbarch, &arc_disassembler_options);
+  set_gdbarch_valid_disassembler_options (gdbarch,
+					  disassembler_options_arc ());
+
   tdesc_use_registers (gdbarch, tdesc, std::move (tdesc_data));
 
   return gdbarch;
diff --git a/gdb/doc/gdb.texinfo b/gdb/doc/gdb.texinfo
index 90d827a50e7..d09b86cda95 100644
--- a/gdb/doc/gdb.texinfo
+++ b/gdb/doc/gdb.texinfo
@@ -9879,8 +9879,8 @@ The default value is the empty string.
 
 If it is necessary to specify more than one disassembler option, then
 multiple options can be placed together into a comma separated list.
-Currently this command is only supported on targets ARM, MIPS, PowerPC
-and S/390.
+Currently this command is only supported on targets ARC, ARM, MIPS,
+PowerPC and S/390.
 
 @kindex show disassembler-options
 @item show disassembler-options
diff --git a/gdb/testsuite/gdb.arch/arc-disassembler-options.exp b/gdb/testsuite/gdb.arch/arc-disassembler-options.exp
new file mode 100644
index 00000000000..6bfe06b3d9d
--- /dev/null
+++ b/gdb/testsuite/gdb.arch/arc-disassembler-options.exp
@@ -0,0 +1,45 @@
+# Copyright 2021 Free Software Foundation, Inc.
+
+# 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/>.
+
+# Test ARC disassembler options.
+
+if { ![istarget "arc-*-*"] } then {
+    verbose "Skipping ARC disassembler option test."
+    return
+}
+
+standard_testfile .s
+set objfile [standard_output_file ${testfile}.o]
+
+if { [gdb_compile "${srcdir}/${subdir}/${srcfile}" "${objfile}" object {}] \
+     != "" } {
+    return
+}
+
+clean_restart ${objfile}
+
+proc arc_disassemble_test { func insn mesg } {
+    gdb_test "disassemble $func" \
+	"Dump of assembler code for function $func:\r\n\
+	\[^:\]+:\t$insn\r\nEnd of assembler dump\." \
+	$mesg
+}
+
+# Verify defaults.
+arc_disassemble_test foo "lr\tr0,\\\[tlbpd0\\\]" "disassemble default"
+
+# Verify option overrides.
+gdb_test "set disassembler-options cpu=arcem"
+arc_disassemble_test foo "lr\tr0,\\\[1120\\\]" "disassemble cpu=arcem"
diff --git a/gdb/testsuite/gdb.arch/arc-disassembler-options.s b/gdb/testsuite/gdb.arch/arc-disassembler-options.s
new file mode 100644
index 00000000000..9f64ce43a43
--- /dev/null
+++ b/gdb/testsuite/gdb.arch/arc-disassembler-options.s
@@ -0,0 +1,21 @@
+#  This test is part of GDB, the GNU debugger.
+#
+#  Copyright 2021 Free Software Foundation, Inc.
+#
+#  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/>.
+
+.globl	foo
+foo:
+	lr	r0, [tlbpd0]
+.end	foo
-- 
2.31.1