gdb/testsuite/gdb.arch/amd64-disp-step.exp

# Copyright 2009-2025 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 amd64 displaced stepping.

require is_x86_64_m64_target

set newline "\[\r\n\]*"

set opts {debug nopie}
standard_testfile .S -signal.c

if { [prepare_for_testing "failed to prepare" $testfile "$srcfile $srcfile2" $opts] } {
    return -1
}

gdb_test "set displaced-stepping on" ""
gdb_test "show displaced-stepping" ".* displaced stepping .* is on.*"

if {![runto_main]} {
    return 0
}

##########################################

# Test call/ret.

gdb_test "break test_call" \
    "Breakpoint.*at.* file .*$srcfile, line.*"
gdb_test "break test_call_end" \
    "Breakpoint.*at.* file .*$srcfile, line.*"

gdb_test "break test_ret" \
    "Breakpoint.*at.* file .*$srcfile, line.*"
gdb_test "break test_ret_end" \
    "Breakpoint.*at.* file .*$srcfile, line.*"

gdb_test "continue" \
    "Continuing.*Breakpoint.*, test_call ().*" \
    "continue to test_call"
gdb_test "continue" \
    "Continuing.*Breakpoint.*, test_call_end ().*" \
    "continue to test_call_end"

gdb_test "continue" \
    "Continuing.*Breakpoint.*, test_ret ().*" \
    "continue to test_ret"
gdb_test "continue" \
    "Continuing.*Breakpoint.*, test_ret_end ().*" \
    "continue to test_ret_end"

##########################################

# Test abs-jmp/rep-ret.

gdb_test "break test_abs_jmp" \
    "Breakpoint.*at.* file .*$srcfile, line.*"
gdb_test "break test_abs_jmp_end" \
    "Breakpoint.*at.* file .*$srcfile, line.*"

gdb_test "break test_rep_ret" \
    "Breakpoint.*at.* file .*$srcfile, line.*"
gdb_test "break test_rep_ret_end" \
    "Breakpoint.*at.* file .*$srcfile, line.*"

gdb_test "continue" \
    "Continuing.*Breakpoint.*, test_abs_jmp ().*" \
    "continue to test_abs_jmp"
gdb_test "continue" \
    "Continuing.*Breakpoint.*, test_abs_jmp_end ().*" \
    "continue to test_abs_jmp_end"

gdb_test "continue" \
    "Continuing.*Breakpoint.*, test_rep_ret ().*" \
    "continue to test_rep_ret"
gdb_test "continue" \
    "Continuing.*Breakpoint.*, test_rep_ret_end ().*" \
    "continue to test_rep_ret_end"

##########################################

# Test syscall.

gdb_test "break test_syscall" \
    "Breakpoint.*at.* file .*$srcfile, line.*"
gdb_test "break test_syscall_end" \
    "Breakpoint.*at.* file .*$srcfile, line.*"

gdb_test "continue" \
    "Continuing.*Breakpoint.*, test_syscall ().*" \
    "continue to test_syscall"
gdb_test "continue" \
    "Continuing.*Breakpoint.*, test_syscall_end ().*" \
    "continue to test_syscall_end"

##########################################

# int3 (with prefixes)
# These don't occur in normal code, but gdb should still DTRT.

gdb_test "break test_int3" \
    "Breakpoint.*at.* file .*$srcfile, line.*"
gdb_test "break test_int3_end" \
    "Breakpoint.*at.* file .*$srcfile, line.*"

gdb_test "continue" \
    "Continuing.*Breakpoint.*, test_int3 ().*" \
    "continue to test_int3"

gdb_test "continue" \
    "Continuing.*Breakpoint.*, test_int3_end ().*" \
    "continue to test_int3_end"

##########################################

# Test rip-relative.
# GDB picks a spare register to hold the rip-relative address.
# Exercise all the possibilities (rax-rdi, sans rsp).

# The order must much the order in srcfile.
set rip_regs { "rax" "rbx" "rcx" "rdx" "rbp" "rsi" "rdi" }

# Assign val to all specified regs.

proc set_regs { regs val } {
    global gdb_prompt

    foreach reg ${regs} {
	# Use send_gdb/gdb_expect so that these aren't logged as pass/fail.
	send_gdb "set \$${reg} = ${val}\n"
	gdb_expect 10 {
	    -re "$gdb_prompt $" { 
		verbose "Setting ${reg} to ${val}." 2
	    }
	    timeout {
		warning "Couldn't set ${reg} to ${val}."
	    }
	}
    }
}

# Verify all REGS equal VAL, except EXCEPT_REG which equals
# EXCEPT_REG_VAL.
#
# It is fine for EXCEPT_REG to be the empty string, in which case no
# register will be checked for EXCEPT_REG_VAL.

proc_with_prefix verify_regs { regs val except_reg except_reg_val } {
    global newline

    foreach reg ${regs} {
	set expected ${val}
	if { "${reg}" == "${except_reg}" } {
	    set expected ${except_reg_val}
	}
	# The cast to (int) is because RBP is printed as a pointer.
	gdb_test "p (int) \$${reg}" " = ${expected}${newline}" "${reg} expected value"
    }
}

# Run the rip-relative tests.
#
# TEST_START_LABEL and TEST_END_LABEL are two labels that delimit the
# test in the srcfile.
#
# REG is either the name of a register which is the destination
# location (when testing the add instruction), otherwise REG should be
# the empty string, when testing the 'jmpq*' instruction.
#
# SIGNAL_MODES is a list which always contains 'off' and optionally
# might also contain 'on'.  The 'on' value is only included if the
# target supports sending SIGALRM to the inferior.  The test is
# repeated for each signal mode.  With signal mode 'on' we send a
# signal to the inferior while it is performing a displaced step.
proc rip_test { reg test_start_label test_end_label signal_modes } {
    global srcfile rip_regs

    gdb_test "break ${test_start_label}" \
	"Breakpoint.*at.* file .*$srcfile, line.*"
    gdb_test "break ${test_end_label}" \
	"Breakpoint.*at.* file .*$srcfile, line.*"

    foreach_with_prefix send_signal $signal_modes {
	if {$send_signal eq [lindex $signal_modes 0]} {
	    # The first time through we can just continue to the
	    # breakpoint.
	    gdb_test "continue" \
		"Continuing.*Breakpoint.*, ${test_start_label} ().*" \
		"continue to ${test_start_label}"
	} else {
	    # For the second time through the test we need to jump
	    # back to the beginning.
	    gdb_test "jump ${test_start_label}" \
		"Breakpoint.*, ${test_start_label} ().*" \
		"jump back to ${test_start_label}"
	}

	set_regs ${rip_regs} 0

	if {$send_signal} {
	    # The signal sending tests require that the signal appear to
	    # arrive from an outside source, i.e. we can't use GDB's 'signal'
	    # command to deliver it.
	    #
	    # The signal must arrive while GDB is processing the displaced
	    # step instruction.
	    #
	    # If we use 'signal' to send the signal GDB doesn't actually do
	    # the displaced step, but instead just delivers the signal.
	    set inferior_pid [get_inferior_pid]
	    # Ensure that $inferior_pid refers to a single process.
	    gdb_assert {[expr $inferior_pid > 0]} \
		"check for a sane inferior pid"
	    if {$inferior_pid > 0} {
		remote_exec target "kill -ALRM $inferior_pid"
	    }
	}

	gdb_test "continue" \
	    "Continuing.*Breakpoint.*, ${test_end_label} ().*" \
	    "continue to ${test_end_label}"

	verify_regs ${rip_regs} 0 ${reg} 42
    }
}

if {![target_info exists gdb,nosignals] && ![istarget "*-*-mingw*"]} {
    # Only targets that support SIGALRM can run the signal tests.
    set signal_modes { off on }
} else {
    set signal_modes { off }
}

# The rip-relative add instructions.  There's a test writing to
# each register in RIP_REGS in turn.
foreach reg ${rip_regs} {
    with_test_prefix "add into ${reg}" {
	rip_test $reg "test_rip_${reg}" "test_rip_${reg}_end" $signal_modes
    }
}

# Now test the rip-relative 'jmpq*' instruction.
with_test_prefix "rip-relative jmpq*" {
    rip_test "" "test_jmp" "test_jmp_end" $signal_modes
}

##########################################

# Done, run program to exit.

gdb_continue_to_end "amd64-disp-step"