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# This testcase is part of GDB, the GNU debugger.
# Copyright 2011-2012 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/>.
if { ![support_displaced_stepping] } {
unsupported "displaced stepping"
return -1
}
set syscall_insn ""
# Define the syscall instruction for each target.
if { [istarget "i\[34567\]86-*-linux*"] || [istarget "x86_64-*-linux*"] } {
set syscall_insn "(int|syscall|sysenter)"
} else {
return -1
}
proc disp_step_cross_syscall { syscall } {
global syscall_insn
global gdb_prompt
global pf_prefix
set testfile "disp-step-$syscall"
if [prepare_for_testing ${testfile}.exp ${testfile} ${testfile}.c {debug}] {
untested ${testfile}.exp
return -1
}
if { ![runto main] } then {
fail "run to main ($syscall)"
return
}
set old_pf_prefix $pf_prefix
lappend pf_prefix "$syscall:"
# Delete the breakpoint on main.
gdb_test_no_output "delete break 1"
gdb_test "break marker" "Breakpoint.*at.* file .*${testfile}.c, line.*"
gdb_test_no_output "set displaced-stepping off"
set syscall_bp 0
gdb_test_multiple "break $syscall" "break $syscall" {
-re "Breakpoint (\[0-9\]*) at .*$gdb_prompt $" {
set syscall_bp $expect_out(1,string)
pass "break $syscall"
}
}
gdb_test "continue" "Continuing\\..*Breakpoint \[0-9\]+, (.* in |__libc_|)$syscall \\(\\).*" \
"continue to $syscall (1st time)"
# Hit the breakpoint on $syscall for the first time. In this time, we will let PLT
# resolution done, and the number single steps we will do later will be
# reduced.
gdb_test "continue" "Continuing\\..*Breakpoint \[0-9\]+, (.* in |__libc_|)$syscall \\(\\).*" \
"continue to $syscall (2nd time)"
# Hit the breakpoint on $syscall for the second time. In this time, the address
# of syscall insn and next insn of syscall are recorded.
gdb_test "display/i \$pc" ".*"
# Single step until we see sysall insn or we reach the upper bound of loop
# iterations.
set see_syscall_insn 0
for {set i 0} {$i < 1000 && $see_syscall_insn == 0} {incr i} {
send_gdb "stepi\n"
gdb_expect {
-re ".*$syscall_insn.*$gdb_prompt $" {
set see_syscall_insn 1
}
-re ".*$gdb_prompt $" {}
}
}
if {$see_syscall_insn == 0} then {
fail "find syscall insn in $syscall"
set pf_prefix $old_pf_prefix
return -1
}
set syscall_insn_addr [get_hexadecimal_valueof "\$pc" "0"]
gdb_test "stepi" ".*" "stepi $syscall insn"
set syscall_insn_next_addr [get_hexadecimal_valueof "\$pc" "0"]
gdb_test "continue" "Continuing\\..*Breakpoint \[0-9\]+, (.* in |__libc_|)$syscall \\(\\).*" \
"continue to $syscall (3rd time)"
# Hit the breakpoint on $syscall for the third time. In this time, we'll set
# breakpoint on the syscall insn we recorded previously, and single step over it.
set syscall_insn_bp 0
gdb_test_multiple "break \*$syscall_insn_addr" "break on syscall insn" {
-re "Breakpoint (\[0-9\]*) at .*$gdb_prompt $" {
set syscall_insn_bp $expect_out(1,string)
pass "break on syscall insns"
}
}
gdb_test_no_output "delete $syscall_bp" "delete break $syscall"
gdb_test "continue" "Continuing\\..*Breakpoint \[0-9\]+, .*" \
"continue to syscall insn $syscall"
gdb_test_no_output "set displaced-stepping on"
# Check the address of next instruction of syscall.
gdb_test "stepi" ".*$syscall_insn_next_addr.*" "single step over $syscall"
# Delete breakpoint syscall insns to avoid interference to other syscalls.
gdb_test_no_output "delete $syscall_insn_bp" "delete break $syscall insn"
gdb_test "continue" "Continuing\\..*Breakpoint \[0-9\]+, marker \\(\\) at.*" \
"continue to marker ($syscall)"
set pf_prefix $old_pf_prefix
}
disp_step_cross_syscall "fork"
disp_step_cross_syscall "vfork"
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