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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/>.

# Setup a line table where:
#
# |      |      |      |      | Inline | Inline |
# | Addr | File | Line | Stmt | Rng A  | Rng B  |
# |------|------|------|------|--------|--------|
# | 1    | 1    | 16   | Y    |        |        |
# | 2    | 1    | 17   | Y    |        |        |
# | 3    | 2    | 21   | Y    | X      |        |
# | 4    | 2    | 22   | Y    | X      |        |
# | 4    | 1    | 18   | N    | X      |        |
# | 5    | 2    | 23   | N    | X      | X      |
# | 6    | 1    | 24   | Y    |        |        |
# | 7    | 1    | END  | Y    |        |        |
# |------|------|------|------|--------|--------|
#
# Places a brekpoint at file 2, line 22.  Previously GDB would discard
# the line table entry for this line due to switching files for the
# file 1, line 18 non-statement line.  After patching however, GDB now
# discards the file 1, line 18 entry instead, and the breakpoint at
# line 22 should succeed.
#
# The two inlined subroutine ranges 'A' and 'B' represent two possible
# ways that a compiler might represent this siuatio in the DWARF.
#
# Range 'B' is something that has been seen in the wild using GCC 8.2.
# In this case the compilers range information is clearly wrong, but
# this shouldn't impact the main point of the test.
#
# Range 'A' is a hypothetical case of how the compiler might choose to
# represent this range, this has never been seen in the wild, but is
# an improved debug experiece over range 'B'.  However, if we ever run
# in to the situation where GDB can support the range 'A' test, or
# support some real DWARF seen in the wild, then the range 'A' case
# should be dropped in favour of supporting real world cases.  This is
# included here as it "just worked" once the range 'B' case was
# working.

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
}

# Prepare and run the test.
proc do_test { start_label func_name tag } {
    global srcfile srcfile2 srcfile3 srcfile4 testfile

    standard_testfile dw2-inline-header-lbls.c dw2-inline-header-${tag}.S \
	dw2-inline-header.c dw2-inline-header.h

    set build_options {nodebug optimize=-O1}

    set asm_file [standard_output_file $srcfile2]
    Dwarf::assemble $asm_file {
	global srcdir subdir srcfile srcfile3 srcfile4 testfile
	upvar build_options build_options
	upvar start_label start_label
	declare_labels lines_label callee_subprog_label

	get_func_info main $build_options

	cu {} {
	    compile_unit {
		{producer "gcc" }
		{language @DW_LANG_C}
		{name ${srcfile3}}
		{low_pc 0 addr}
		{stmt_list ${lines_label} DW_FORM_sec_offset}
	    } {
		callee_subprog_label: subprogram {
		    {external 1 flag}
		    {name callee}
		    {inline 3 data1}
		}
		subprogram {
		    {external 1 flag}
		    {name main}
		    {low_pc $main_start addr}
		    {high_pc "$main_start + $main_len" addr}
		} {
		    inlined_subroutine {
			{abstract_origin %$callee_subprog_label}
			{low_pc $start_label addr}
			{high_pc line_label_6 addr}
			{call_file 1 data1}
			{call_line 18 data1}
		    }
		}
	    }
	}

	lines {version 2 default_is_stmt 1} lines_label {
	    include_dir "${srcdir}/${subdir}"
	    file_name "$srcfile3" 1
	    file_name "$srcfile4" 1

	    program {
		{DW_LNE_set_address line_label_1}
		{DW_LNS_advance_line 15}
		{DW_LNS_copy}

		{DW_LNE_set_address line_label_2}
		{DW_LNS_advance_line 1}
		{DW_LNS_copy}

		{DW_LNS_set_file 2}
		{DW_LNE_set_address line_label_3}
		{DW_LNS_advance_line 4}
		{DW_LNS_copy}

		{DW_LNE_set_address line_label_4}
		{DW_LNS_advance_line 1}
		{DW_LNS_copy}

		{DW_LNS_advance_line -4}
		{DW_LNS_set_file 1}
		{DW_LNS_negate_stmt}
		{DW_LNS_copy}

		{DW_LNS_set_file 2}
		{DW_LNE_set_address line_label_5}
		{DW_LNS_advance_line 5}
		{DW_LNS_copy}

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

		{DW_LNE_set_address line_label_7}
		{DW_LNE_end_sequence}
	    }
	}
    }

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

    if ![runto_main] {
	return -1
    }

    # Delete all breakpoints so that the output of "info breakpoints"
    # below will only contain a single breakpoint.
    delete_breakpoints

    # Place a breakpoint within the function in the header file.
    gdb_breakpoint "${srcfile4}:22"

    # Check that the breakpoint was placed where we expected.  It should
    # appear at the requested line.  When the bug in GDB was present the
    # breakpoint would be placed on one of the following lines instead.
    gdb_test "info breakpoints" \
	".* in $func_name at \[^\r\n\]+${srcfile4}:22\\y.*" \
	"info breakpoints, $tag"
}

do_test line_label_3 "callee" "range-a"
do_test line_label_5 "main" "range-b"