Add memory tagging testcasesusers/luisgpm/aarch64-mte-v1

Add an AArch64-specific test and a more generic memory tagging test that
other architectures can run.

Even though architectures not supporting memory tagging can run the memory
tagging tests, the runtime check will make the tests bail out early, as it
would make no sense to proceed without proper support.

gdb/testsuite/ChangeLog:

YYYY-MM-DD  Luis Machado  <luis.machado@linaro.org>

	* gdb.arch/aarch64-mte.c: New file.
	* gdb.arch/aarch64-mte.exp: New test.
	* gdb.base/memtag.c: New file.
	* gdb.base/memtag.exp: New test.
	* lib/gdb.exp (supports_memtag): New function.

5 files changed, 315 insertions, 0 deletions

diff --git a/gdb/testsuite/gdb.arch/aarch64-mte.c b/gdb/testsuite/gdb.arch/aarch64-mte.c
new file mode 100644
index 00000000000..63a42ae2780
--- /dev/null
+++ b/gdb/testsuite/gdb.arch/aarch64-mte.c
@@ -0,0 +1,22 @@
+/* This test program is part of GDB, the GNU debugger.
+
+   Copyright 2020 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/>.  */
+
+int
+main (int argc, char **argv)
+{
+  return 0;
+}
diff --git a/gdb/testsuite/gdb.arch/aarch64-mte.exp b/gdb/testsuite/gdb.arch/aarch64-mte.exp
new file mode 100644
index 00000000000..aa25cc3036e
--- /dev/null
+++ b/gdb/testsuite/gdb.arch/aarch64-mte.exp
@@ -0,0 +1,196 @@
+# Copyright (C) 2020 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 a binary with address signing works regardless of whether the target
+# supports pauth instructions.  On non pauth systems, all pauth instructions
+# are treated as nops.
+
+global hex
+global decimal
+
+# Return TAG in hex format with no leading zeroes.
+proc get_hex_tag { tag } {
+    return [format "%x" $tag]
+}
+
+# Return TAG in the NN format where N is 4 bits of the byte.
+proc get_tag_nn { tag } {
+    return [format "%02x" $tag]
+}
+
+# Return the address of PTR with a tag of TAG.
+proc get_tagged_ptr { tag ptr } {
+  return [get_valueof "/x" \
+	      "${ptr} & (0x00ffffffffffffff) | ((unsigned long) ${tag} << 56)" \
+	      "0" "fetch pointer ${ptr} with tag ${tag}"]
+}
+
+# Return the logical TAG from PTR.
+proc get_ltag_from_ptr { ptr } {
+  return [get_valueof "/x" "$ptr >> 56 & 0xf" -1 "fetch tag from pointer ${ptr}"]
+}
+
+if {![is_aarch64_target]} {
+    verbose "Skipping ${gdb_test_file_name}."
+    return
+}
+
+standard_testfile
+if { [prepare_for_testing "failed to prepare" ${testfile} ${srcfile}] } {
+    return -1
+}
+
+if ![runto_main] {
+    untested "could not run to main"
+    return -1
+}
+
+# Targets that don't support memory tagging should not execute the
+# runtime memory tagging tests.
+if {![supports_memtag]} {
+    untested "memory tagging unsupported"
+    return -1
+}
+
+with_test_prefix "literals" {
+    set setatag_msg "Allocation tag\\(s\\) updated successfully\."
+    set check_msg "Memory tags match\."
+
+    # Test setting and showing the logical tags.
+    for {set i 0} {$i < 32} {incr i} {
+	set addr [get_tagged_ptr $i 0xdeadbeef]
+	set tag [get_hex_tag [expr $i % 16]]
+	gdb_test "mtag showltag $addr" " = 0x${tag}" "showltag with tag ${i}"
+
+	set tag_nn [get_tag_nn $i]
+	gdb_test "mtag setltag ${addr} ${tag_nn}" " = \\(void \\*\\) ${addr}" \
+		 "setltag with tag ${i}"
+    }
+
+    # Fetch the pointer to a known PROT_MTE-mapped area.
+    set tagged_ptr [get_hexadecimal_valueof "argv" -1]
+
+    if {$tagged_ptr == -1} {
+	untested "unexpected pointer or tag value"
+	return -1
+    }
+
+    # Test setting and showing the allocation tags
+    for {set i 0} {$i < 32} {incr i} {
+
+	set tag_nn [get_tag_nn $i]
+	gdb_test "mtag setatag $tagged_ptr 0 ${tag_nn}" \
+		 $setatag_msg \
+		 "setatag with tag ${i}"
+
+	set tag [get_hex_tag [expr $i % 16]]
+	gdb_test "mtag showatag $tagged_ptr" " = 0x${i}" \
+		 "showatag with tag ${i}"
+    }
+
+    # Test tag mismatches.
+    with_test_prefix "tag mismatches" {
+	for {set i 0} {$i < 32} {incr i} {
+
+	    # Set the allocation tag to a known value.
+	    set tag_nn [get_tag_nn $i]
+	    gdb_test "mtag setatag $tagged_ptr 0 ${tag_nn}" \
+		     $setatag_msg \
+		     "setatag with tag ${i}"
+
+	    # Validate that the logical tag matches against the allocation
+	    # tag.
+	    set addr [get_tagged_ptr $i $tagged_ptr]
+	    gdb_test "mtag check $addr" $check_msg \
+		     "check match with tag ${i}"
+
+	    # Get a pointer with the logical tag that does not match the
+	    # allocation tag.
+	    set ltag [expr $i + 1]
+	    with_test_prefix "fetch mismatch tag" {
+		set addr [get_tagged_ptr $ltag $tagged_ptr]
+	    }
+
+	    # Validate that the logical tag does not match the allocation
+	    # tag.
+	    set ltag [get_hex_tag [expr [expr $i + 1]% 16]]
+	    set atag [get_hex_tag [expr $i % 16]]
+	    gdb_test "mtag check $addr" \
+		     "Logical tag \\(0x${ltag}\\) does not match the allocation tag \\(0x${atag}\\)\." \
+		     "check mismatch with tag ${i}"
+	}
+    }
+
+}
+
+# Test the memory tagging extensions for the "print" command.
+with_test_prefix "print command" {
+    set ptr_name "argv"
+    set tagged_ptr [get_hexadecimal_valueof $ptr_name -1]
+
+    if {$tagged_ptr == -1} {
+	untested "unexpected pointer or tag value"
+	return -1
+    }
+
+    set ltag [get_ltag_from_ptr ${tagged_ptr}]
+
+    if {$ltag == -1} {
+	untested "unexpected tag value"
+	return -1
+    }
+
+    set atag [expr [expr $ltag + 1] % 16]
+    set atag_nn [get_tag_nn $atag]
+
+    gdb_test "mtag setatag $tagged_ptr 0 ${atag_nn}" \
+	     $setatag_msg \
+	     "make atag and ltag different"
+
+    gdb_test "p $ptr_name" \
+	[multi_line \
+	    "Logical tag \\(${ltag}\\) does not match Allocation tag \\(0x${atag}\\)\." \
+	    "\\\$\[0-9\]+ = \\(.*\\) (0|$hex)( <.*>)?\[\r\n\]+"] \
+	"show tag mismatch"
+}
+
+# Test the memory tagging extensions for the "x" command.
+with_test_prefix "x command" {
+    set ptr_name "argv"
+
+    # Check if the allocation tags match what we expect.
+    gdb_test "x/gxm argv" \
+	[multi_line \
+	    "<Allocation Tag $hex for range \\\[$hex,$hex\\)>" \
+	    "$hex:\[ \t\]+$hex"] \
+	"outputs tag information"
+}
+
+# Validate the presence of the MTE registers.
+foreach reg {"sctlr" "gcr"} {
+    gdb_test "info registers $reg" \
+	     "$reg\[ \t\]+$hex\[ \t\]+$decimal" \
+	     "register $reg available"
+}
+
+# Run until a crash and confirm GDB displays memory tag violation
+# information.
+gdb_test "continue" \
+    [multi_line \
+	"Memory tag violation while accessing address $hex" \
+	"Logical tag $hex" \
+	"Allocation tag $hex" \
+	"$hex in main \\(argc=1, argv=0xfffffffff3b8\\) at .*"] \
+	 "display tag violation information"
diff --git a/gdb/testsuite/gdb.base/memtag.c b/gdb/testsuite/gdb.base/memtag.c
new file mode 100644
index 00000000000..63a42ae2780
--- /dev/null
+++ b/gdb/testsuite/gdb.base/memtag.c
@@ -0,0 +1,22 @@
+/* This test program is part of GDB, the GNU debugger.
+
+   Copyright 2020 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/>.  */
+
+int
+main (int argc, char **argv)
+{
+  return 0;
+}
diff --git a/gdb/testsuite/gdb.base/memtag.exp b/gdb/testsuite/gdb.base/memtag.exp
new file mode 100644
index 00000000000..657f40daaa0
--- /dev/null
+++ b/gdb/testsuite/gdb.base/memtag.exp
@@ -0,0 +1,59 @@
+# Copyright 2020 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/>.
+
+# Exercise the various bits of memory tagging support in GDB.
+
+# Return 0 if memory tagging is supported.
+# Return 1 otherwise.
+
+set u_msg "Memory tagging not supported or disabled by the current architecture\."
+
+standard_testfile
+if {[prepare_for_testing "failed to prepare" ${testfile} ${srcfile}]} {
+    return -1
+}
+
+# Test commands without running the program.
+with_test_prefix "before program execution" {
+    # These commands should all fails without a running program.
+    foreach subcmd {"setltag" "showltag" "setatag" "showatag" "check"} {
+	gdb_test "mtag $subcmd" "$u_msg"
+    }
+}
+
+if ![runto_main] {
+    untested "could not run to main"
+    return -1
+}
+
+# Targets that don't support memory tagging should not execute the
+# runtime memory tagging tests.
+if {![supports_memtag]} {
+    untested "memory tagging unsupported"
+    return -1
+}
+
+# With the program running, try to use the memory tagging commands.
+with_test_prefix "during program execution" {
+    set msg "Argument required \\(address or pointer\\)\."
+
+    # Test the various mtag commands again.
+    gdb_test "mtag showltag" $msg
+    gdb_test "mtag showatag" $msg
+    gdb_test "mtag setltag" "Arguments required \\(<address> <tag>\\)\."
+    gdb_test "mtag setatag"
+	     "Arguments required \\(<starting address> <length> <tag bytes>\\)\."
+    gdb_test "mtag check" $msg
+}
diff --git a/gdb/testsuite/lib/gdb.exp b/gdb/testsuite/lib/gdb.exp
index f502eb157d8..0e87c869263 100644
--- a/gdb/testsuite/lib/gdb.exp
+++ b/gdb/testsuite/lib/gdb.exp
@@ -2613,6 +2613,22 @@ proc supports_get_siginfo_type {} {
     }
 }
 
+# Return 1 if memory tagging is supported at runtime, otherwise return 0.
+
+proc supports_memtag {} {
+    global gdb_prompt
+
+    gdb_test_multiple "mtag check" "" {
+	-re "Memory tagging not supported or disabled by the current architecture\..*$gdb_prompt $" {
+	  return 0
+	}
+	-re "Argument required \\(address or pointer\\).*$gdb_prompt $" {
+	    return 1
+	}
+    }
+    return 0
+}
+
 # Return 1 if the target supports hardware single stepping.
 
 proc can_hardware_single_step {} {