Re: [PATCH 2/2,v3] [AArch64] Test handling of additional brk instruction patterns

[Alan Hayward <Alan.Hayward@arm.com>]

Minor nit below. Happy for it to be pushed with that one change.

Alan.

> On 15 Jan 2020, at 11:51, Luis Machado <luis.machado@linaro.org> wrote:
> 
> New in v3:
> 
> - Minor formatting and code cleanups.
> - Added count check to validate number of brk SIGTRAP's.
> - Moved count to SIGTRAP check conditional block.
> 
> This test exercises the previous patch's code and makes sure GDB can
> properly get a SIGTRAP from various brk instruction patterns.
> 
> GDB needs to be able to see the program exiting normally. If GDB doesn't
> support the additional brk instructions, we will see timeouts.
> 
> We bail out with the first timeout since we won't be able to step through
> the program breakpoint anyway, so it is no use carrying on.
> 
> gdb/testsuite/ChangeLog:
> 
> 2020-01-15  Luis Machado  <luis.machado@linaro.org>
> 
> 	* gdb.arch/aarch64-brk-patterns.c: New source file.
> 	* gdb.arch/aarch64-brk-patterns.exp: New test.
> ---
> gdb/testsuite/gdb.arch/aarch64-brk-patterns.c | 30 ++++++++
> .../gdb.arch/aarch64-brk-patterns.exp         | 74 +++++++++++++++++++
> 2 files changed, 104 insertions(+)
> create mode 100644 gdb/testsuite/gdb.arch/aarch64-brk-patterns.c
> create mode 100644 gdb/testsuite/gdb.arch/aarch64-brk-patterns.exp
> 
> diff --git a/gdb/testsuite/gdb.arch/aarch64-brk-patterns.c b/gdb/testsuite/gdb.arch/aarch64-brk-patterns.c
> new file mode 100644
> index 0000000000..ccf9a35a94
> --- /dev/null
> +++ b/gdb/testsuite/gdb.arch/aarch64-brk-patterns.c
> @@ -0,0 +1,30 @@
> +/* This file 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(void)

New line between int and main.

> +{
> +  /* Dummy instruction just so GDB doesn't stop at the first breakpoint
> +     instruction.  */
> +  __asm __volatile ("nop\n\t");
> +
> +  /* Multiple BRK instruction patterns.  */
> +  __asm __volatile ("brk %0\n\t" ::"n"(0x0));
> +  __asm __volatile ("brk %0\n\t" ::"n"(0x900 + 0xf));
> +  __asm __volatile ("brk %0\n\t" ::"n"(0xf000));
> +
> +  return 0;
> +}
> diff --git a/gdb/testsuite/gdb.arch/aarch64-brk-patterns.exp b/gdb/testsuite/gdb.arch/aarch64-brk-patterns.exp
> new file mode 100644
> index 0000000000..9a0ec81efa
> --- /dev/null
> +++ b/gdb/testsuite/gdb.arch/aarch64-brk-patterns.exp
> @@ -0,0 +1,74 @@
> +# 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/>.
> +#
> +# This file is part of the gdb testsuite.
> +
> +# Test if GDB stops at various BRK instruction patterns inserted into
> +# the code.
> +
> +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
> +}
> +
> +# Number of expected SIGTRAP's to get.  This needs to be kept in sync
> +# with the source file.
> +set expected_traps 3
> +set keep_going 1
> +set count 0
> +set old_timeout $timeout
> +set timeout 10
> +
> +while {$keep_going} {
> +
> +  set test "brk instruction $count causes SIGTRAP"
> +
> +  # Continue to next program breakpoint instruction.
> +  gdb_test_multiple "continue" $test {
> +      -re "Program received signal SIGTRAP, Trace/breakpoint trap.*$gdb_prompt $" {
> +	  pass $test
> +
> +	  # Insert a breakpoint at the program breakpoint instruction so GDB
> +	  # can step over it.
> +	  gdb_test "break" \
> +	    "Breakpoint $decimal at $hex: file .*$srcfile, line $decimal.*" \
> +	    "insert breakpoint at brk instruction $count"
> +	  incr count
> +      }
> +      -re "exited normally.*$gdb_prompt $" {
> +	  set keep_going 0
> +      }
> +      timeout {
> +	  fail $test
> +	  set keep_going 0
> +      }
> +  }
> +}
> +
> +set timeout $old_timeout
> +
> +if {$count < $expected_traps} {
> +  fail "all brk instructions triggered."
> +}
> -- 
> 2.17.1
>