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# This testcase is part of GDB, the GNU debugger.
#
# Copyright 2013-2020 Free Software Foundation, Inc.
#
# Contributed by Intel Corp. <markus.t.metzger@intel.com>
#
# 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/>.

if { [skip_btrace_tests] } {
    unsupported "target does not support record-btrace"
    return -1
}

# This test requires the compiler to generate a tail call.  To guarantee that
# we always get one, we use an assembly source file.
#
# We use different assembly sources based on the target architecture.
#
# Luckily, they are similar enough that a single test script can handle
# both.
set opts {}
if [info exists COMPILE] {
    # make check RUNTESTFLAGS="gdb.btrace/tailcall.exp COMPILE=1"
    standard_testfile tailcall.c
    lappend opts debug optimize=-O2
} elseif {[istarget "i?86-*-*"] || [istarget "x86_64-*-*"]} {
	if {[is_amd64_regs_target]} {
		standard_testfile x86_64-tailcall.S
	} else {
		standard_testfile i686-tailcall.S
	}
} else {
    unsupported "target architecture not supported"
    return -1
}

if [prepare_for_testing "failed to prepare" $testfile $srcfile $opts] {
    return -1
}
if ![runto_main] {
    untested "failed to run to main"
    return -1
}

# we want to see the full trace for this test
gdb_test_no_output "set record function-call-history-size 0"

# trace the call to foo
gdb_test_no_output "record btrace"
gdb_test "next 2"

# show the flat branch trace
gdb_test "record function-call-history 1" [multi_line \
  "1\tmain" \
  "2\tfoo" \
  "3\tbar" \
  "4\tmain" \
  ] "flat"

# show the branch trace with calls indented
gdb_test "record function-call-history /c 1" [multi_line \
  "1\tmain" \
  "2\t  foo" \
  "3\t    bar" \
  "4\tmain" \
  ] "indented"

# go into bar
gdb_test "record goto 4" ".*bar \\(\\) at .*tailcall.c:24\r\n.*"

# check the backtrace
gdb_test "backtrace" [multi_line \
  "#0.*bar \\(\\) at tailcall.c:24" \
  "#1.*foo \\(\\) at tailcall.c:29" \
  "#2.*main \\(\\) at tailcall.c:37" \
  "Backtrace stopped: not enough registers or memory available to unwind further" \
  ]

# walk the backtrace
gdb_test "up" "#1\[^\r\n\]*foo \\(\\) at tailcall.c:29\r\n.*" "up to foo"
gdb_test "up" "#2\[^\r\n\]*main \\(\\) at tailcall.c:37\r\n.*" "up to main"
gdb_test "down" "#1\[^\r\n\]*foo \\(\\) at tailcall.c:29\r\n.*" "down to foo"

# test stepping into and out of tailcalls.
gdb_test "finish" "\[^\r\n\]*main \\(\\) at tailcall.c:38\r\n.*"
gdb_test "reverse-step" "\[^\r\n\]*bar \\(\\) at tailcall.c:24\r\n.*"
gdb_test "reverse-finish" "\[^\r\n\]*foo \\(\\) at tailcall.c:29\r\n.*"
gdb_test "reverse-step" "\[^\r\n\]*main \\(\\) at tailcall.c:37\r\n.*"
gdb_test "next" "\[^\r\n\]*38.*"
gdb_test "reverse-next" "\[^\r\n\]*main \\(\\) at tailcall.c:37\r\n.*"
gdb_test "step" "\[^\r\n\]*foo \\(\\) at tailcall.c:29\r\n.*"
gdb_test "finish" "\[^\r\n\]*main \\(\\) at tailcall.c:38\r\n.*"
gdb_test "reverse-step" "\[^\r\n\]*bar \\(\\) at tailcall.c:24\r\n.*"
gdb_test "finish" "\[^\r\n\]*main \\(\\) at tailcall.c:38\r\n.*"