gdb/testsuite/gdb.arch/i386-disp-step-self-call.exp

# Copyright 2023-2025 Free Software Foundation, Inc.

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# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 3 of the License, or
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#
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# GNU General Public License for more details.
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# Test i386 displaced stepping over a call instruction that calls to
# itself.  This is pretty unlikely to be seen in the wild, but does
# test a corner case of our displaced step handling.

require is_x86_like_target

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

set opts {debug nopie}
standard_testfile .S -alarm.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
}

# Proceed to the test function.
gdb_breakpoint "test_call"
gdb_continue_to_breakpoint "test_call"

# Get the current stack pointer value.
set sp [get_hexadecimal_valueof "\$sp" "*UNKNOWN*"]

# Get the address of the next instruction.
set next_insn_addr ""
gdb_test_multiple "x/2i \$pc" "get address of next insn" {
    -re "\r\n=> $hex \[^\r\n\]+\r\n" {
	exp_continue
    }
    -re "^   ($hex) \[^\r\n\]+\r\n" {
	set next_insn_addr $expect_out(1,string)
	exp_continue
    }
    -re "^$::gdb_prompt $" {
	gdb_assert {![string equal $next_insn_addr ""]} \
	    $gdb_test_name
    }
}

# Clear the slot on the stack and confirm it was set to zero.
set sp [expr $sp - 0x4]
gdb_test_no_output "set {unsigned int} $sp = 0" \
    "clear stack slot"
set zero_val 0x[format %08x 0]
gdb_test "x/1wx 0x[format %x $sp]" "$hex:\\s+${zero_val}" \
    "check return address slot was set to zero"

# Single step.
gdb_test "stepi" \
    "Breakpoint $decimal, test_call \\(\\) at .*"

# Check stack pointer was updated to the expected value.
set new_sp [get_hexadecimal_valueof "\$sp" "*UNKNOWN*" \
	       "get stack pointer after step"]
gdb_assert {[expr $sp == $new_sp]} \
    "check stack pointer was updated as expected"

# Check the contents of the stack were updated to the expected value.
set next_insn_addr 0x[format %08x $next_insn_addr]
gdb_test "x/1wx 0x[format %x $sp]" "$hex:\\s+$next_insn_addr" \
    "check return address was updated correctly"