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Elixir Cross Referencer

# Copyright 2020 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/>.

# Create an example function that contains both addresses marked as
# statements and addresses marked as non-statements, and then
# disassemble the function.
#
# Of particular interest is how 'disassemble /m' handles the
# non-statement addresses, we want to ensure that these addresses are
# included in the disassembly output.  For completeness we test both
# 'disassemble /m' and 'disassemble /s'.

load_lib dwarf.exp

# This test can only be run on targets which support DWARF-2 and use gas.
if {![dwarf2_support]} {
    return 0
}

# The .c files use __attribute__.
if [get_compiler_info] {
    return -1
}
if !$gcc_compiled {
    return 0
}

# Reuse many of the test source files from dw2-inline-header-1.exp.
standard_testfile dw2-inline-header-lbls.c dw2-inline-header.S \
    dw2-inline-header.c

set asm_file [standard_output_file $srcfile2]
Dwarf::assemble $asm_file {
    global srcdir subdir srcfile srcfile3
    declare_labels lines_label

    get_func_info main

    cu {} {
	compile_unit {
	    {producer "gcc" }
	    {language @DW_LANG_C}
	    {name ${srcfile3}}
	    {low_pc 0 addr}
	    {stmt_list ${lines_label} DW_FORM_sec_offset}
	} {
	    subprogram {
		{external 1 flag}
		{MACRO_AT_func {main}}
	    }
	}
    }

    lines {version 2 default_is_stmt 1} lines_label {
	include_dir "${srcdir}/${subdir}"
	file_name "$srcfile3" 1

	program {
	    {DW_LNE_set_address $main_start}
	    {DW_LNS_advance_line 15}
	    {DW_LNS_copy}

	    {DW_LNE_set_address line_label_2}
	    {DW_LNS_negate_stmt}
	    {DW_LNS_copy}

	    {DW_LNE_set_address line_label_3}
	    {DW_LNS_advance_line 1}
	    {DW_LNS_copy}

	    {DW_LNE_set_address line_label_4}
	    {DW_LNS_negate_stmt}
	    {DW_LNS_copy}

	    {DW_LNE_set_address line_label_5}
	    {DW_LNS_negate_stmt}
	    {DW_LNS_copy}

	    {DW_LNE_set_address line_label_6}
	    {DW_LNS_advance_line 1}
	    {DW_LNS_negate_stmt}
	    {DW_LNS_copy}

	    {DW_LNE_set_address $main_end}
	    {DW_LNS_copy}
	    {DW_LNE_end_sequence}
	}
    }
}

if { [prepare_for_testing "failed to prepare" ${testfile} \
	  [list $srcfile $asm_file] {nodebug} ] } {
    return -1
}

if ![runto_main] {
    return -1
}

# Global lines array, maps lines numbers to the list of addresses
# associated with that line in the debug output.
array set lines {}

# Look in the global LINES array and check that the disassembly for
# line LINENUM includes the address of LABEL.
proc check_disassembly_results { linenum label } {
    global lines

    set address [get_hexadecimal_valueof "&${label}" "__unknown__"]
    set testname "check_disassembly_results $linenum $label"
    if {![info exists lines($linenum)]} {
	fail "$testname (no disassembly for $linenum)"
	return
    }

    # Use a loop to compare the addresses as the addresses extracted
    # from the disassembly output can be padded with zeros, while the
    # address of the label will not be padded.
    set addrs $lines($linenum)
    foreach a $addrs {
	if { $a == $address } {
	    pass $testname
	    return
	}
    }
    fail $testname
}

foreach_with_prefix opt { m s } {
    # Disassemble 'main' and split up the disassembly output.  We
    # build an associative array, for each line number store the list
    # of addresses that were part of its disassembly output.
    #
    # LINENUM is the line we are currently collecting the disassembly
    # addresses for, and ADDRS is the list of addresses collected for
    # this line.
    set linenum -1
    set addrs {}

    # Clear the global associative array used to hold the results.
    unset lines
    array set lines {}

    gdb_test_multiple "disassemble /${opt} main" "" {
	-re "Dump of assembler code for function main:\r\n" {
	    exp_continue
	}

	-re "^\[^\r\n\]+${srcfile3}:" {
	    exp_continue
	}

	-re "^(\\d+)\\s+\[^\r\n\]+\r\n" {
	    if { $linenum != -1 } {
		set lines($linenum) $addrs
		set addrs {}
	    }
	    set linenum $expect_out(1,string)
	    exp_continue
	}

	-re "^(?:=>)?\\s*($hex)\\s*\[^\r\n\]+\r\n" {
	    set address $expect_out(1,string)
	    lappend addrs $address
	    exp_continue
	}

	-re "^\\s*\r\n" {
	    exp_continue
	}

	-re "^End of assembler dump\\.\r\n" {
	    if { $linenum != -1 } {
		set lines($linenum) $addrs
		set linenum -1
		set addrs {}
	    }
	    exp_continue
	}

	-re "^$gdb_prompt $" {
	    # All done.
	}
    }

    # Now check that each label we expect to be associated with each line
    # shows up in the disassembly output.
    check_disassembly_results 16 "line_label_1"
    check_disassembly_results 16 "line_label_2"
    check_disassembly_results 17 "line_label_3"
    check_disassembly_results 17 "line_label_4"
    check_disassembly_results 17 "line_label_5"
    check_disassembly_results 18 "line_label_6"
}