# Copyright 2009-2021 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 multi-exec / multi-process features that work for all configurations,
# even ones that cannot run multiple processes simultaneously.

set testfile "multi-arch-exec"

# The plain remote target can't do multiple inferiors.
if [use_gdb_stub] {
    return
}

# The 64-bit compile may succeed for i386-linux, but gdb won't be able
# to load the file.
if [istarget "i?86-*linux*"] {
    return
}

# The testcase builds two programs, each of its own architecture.  For
# example, one built with -m64, another with -m32.  The exact compiler
# options depends on target triplet.  We generically refer to the
# architectures simply as 'architecture 1' and 'architecture 2'.  Each
# program is actually built twice, once for each architecture, because
# we test both execing from arch1 to arch2 and from arch2 to arch1.
# The architecture of the executable that execs is encoded in the
# binaries' names, like so:
#
#    $first_arch-multi-arch-exec         # execing program
#    $first_arch-multi-arch-exec-hello   # execed program

# Append the options necessary to build a program for architecture 1
# to the OPTIONS_VAR list.

proc append_arch1_options {options_var} {
    upvar 1 $options_var options

    if { [istarget "aarch64*-*-*"] } {
	return 1
    }

    lappend options "additional_flags=-m64"
    return 1
}

# Append the options necessary to build a program for architecture 2
# to the OPTIONS_VAR list.

proc append_arch2_options {options_var} {
    upvar 1 $options_var options

    if { [istarget "aarch64*-*-*"] } {
	if {[info exists ARM_CC_FOR_TARGET]} {
	    lappend options "compiler=${ARM_CC_FOR_TARGET}"
	    return 1
	} else {
	    unsupported "ARM compiler is not known"
	    return 0
	}
    }

    if [istarget "s390*-*-*"] {
	set march "-m31"
    } else {
	set march "-m32"
    }
    lappend options "additional_flags=${march}"
    return 1
}

# Append the options necessary to build a program for architecture
# ARCH to the OPTIONS_VAR list.  Returns true on success.

proc append_arch_options {arch options_var} {
    upvar 1 $options_var options

    if {$arch == 1} {
	return [append_arch1_options options]
    } elseif {$arch == 2} {
	return [append_arch2_options options]
    } else {
	error "unhandled architecture: $arch"
    }
}

# Build the executables for testing with FIRST_ARCH (either 1 or 2) as
# the architecture before the exec.  Returns true on success.

proc build_executables { first_arch } {

    # Can't use standard_testfile, we want executables with specialized
    # names.
    set from_exec "$first_arch-multi-arch-exec"
    set from_srcfile multi-arch-exec.c
    set from_binfile [standard_output_file ${from_exec}]

    set to_exec "$first_arch-multi-arch-exec-hello"
    set to_srcfile hello.c
    set to_binfile [standard_output_file ${to_exec}]

    # Build two executables, one for each arch.

    if {$first_arch == 1} {
	set from_arch 1
	set to_arch 2
    } elseif {$first_arch == 2} {
	set from_arch 2
	set to_arch 1
    } else {
	error "unhandled first architecture: $first_arch"
    }

    set from_options [list debug pthreads]
    if {![append_arch_options $from_arch from_options]} {
	return 0
    }

    if { [build_executable "failed to prepare" ${from_exec} "${from_srcfile}" \
	      $from_options] } {
	return 0
    }

    set to_options [list debug]
    if {![append_arch_options $to_arch to_options]} {
	return 0
    }

    if { [build_executable "failed to prepare" ${to_exec} "${to_srcfile}" \
	      $to_options] } {
	return 0
    }

    return 1
}

proc do_test { first_arch mode selected_thread } {
	set from_exec "$first_arch-multi-arch-exec"

	clean_restart ${from_exec}
	if ![runto all_started] then {
	    return -1
	}

	# Delete the breakpoint at 'all_started' otherwise GDB may
	# switch context back to thread 1 to step over the breakpoint.
	delete_breakpoints

	# A location for this breakpoint should be found in the new
	# post-exec image too.
	gdb_breakpoint main

	gdb_test "thread $selected_thread" "Switching to thread $selected_thread .*"

	gdb_test_no_output "set follow-exec-mode $mode"

	# Test that GDB updates the target description / arch successfuly
	# after the exec.
	gdb_test "continue" "Breakpoint 2, main.*" "continue across exec that changes architecture"
}

# Test both arch1=>arch2 and arch2=>arch1.
foreach_with_prefix first_arch {1 2} {
    if {![build_executables $first_arch]} {
	continue
    }

    # Test handling the exec event with either the main thread or the
    # second thread selected.  This tries to ensure that GDB doesn't read
    # registers off of the execing thread before figuring out its
    # architecture.
    foreach_with_prefix selected_thread {1 2} {
	foreach_with_prefix follow_exec_mode {"same" "new"} {
	    do_test $first_arch $follow_exec_mode $selected_thread
	}
    }
}