cc-with-tweaks.sh revision 1.7 
1#! /bin/sh
2# Wrapper around gcc to tweak the output in various ways when running
3# the testsuite.
4
5# Copyright (C) 2010-2017 Free Software Foundation, Inc.
6# This program is free software; you can redistribute it and/or modify
7# it under the terms of the GNU General Public License as published by
8# the Free Software Foundation; either version 3 of the License, or
9# (at your option) any later version.
10#
11# This program is distributed in the hope that it will be useful,
12# but WITHOUT ANY WARRANTY; without even the implied warranty of
13# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14# GNU General Public License for more details.
15#
16# You should have received a copy of the GNU General Public License
17# along with this program.  If not, see <http://www.gnu.org/licenses/>.
18
19# This program requires gdb and objcopy in addition to gcc.
20# The default values are gdb from the build tree and objcopy from $PATH.
21# They may be overridden by setting environment variables GDB and OBJCOPY
22# respectively.  Note that GDB should contain the gdb binary as well as the
23# -data-directory flag, e.g., "foo/gdb -data-directory foo/data-directory".
24# We assume the current directory is either $obj/gdb or $obj/gdb/testsuite.
25#
26# Example usage:
27#
28# bash$ cd $objdir/gdb/testsuite
29# bash$ runtest \
30#   CC_FOR_TARGET="/bin/sh $srcdir/gdb/contrib/cc-with-tweaks.sh ARGS gcc" \
31#   CXX_FOR_TARGET="/bin/sh $srcdir/gdb/contrib/cc-with-tweaks.sh ARGS g++"
32#
33# For documentation on Fission and dwp files:
34#     http://gcc.gnu.org/wiki/DebugFission
35#     http://gcc.gnu.org/wiki/DebugFissionDWP
36# For documentation on index files: info -f gdb.info -n "Index Files"
37# For information about 'dwz', see the announcement:
38#     http://gcc.gnu.org/ml/gcc/2012-04/msg00686.html
39# (More documentation is to come.)
40
41# ARGS determine what is done.  They can be:
42# -Z invoke objcopy --compress-debug-sections
43# -z compress using dwz
44# -m compress using dwz -m
45# -i make an index
46# -p create .dwp files (Fission), you need to also use gcc option -gsplit-dwarf
47# If nothing is given, no changes are made
48
49myname=cc-with-tweaks.sh
50
51if [ -z "$GDB" ]
52then
53    if [ -f ./gdb ]
54    then
55	GDB="./gdb -data-directory data-directory"
56    elif [ -f ../gdb ]
57    then
58	GDB="../gdb -data-directory ../data-directory"
59    elif [ -f ../../gdb ]
60    then
61	GDB="../../gdb -data-directory ../../data-directory"
62    else
63	echo "$myname: unable to find usable gdb" >&2
64	exit 1
65    fi
66fi
67
68OBJCOPY=${OBJCOPY:-objcopy}
69READELF=${READELF:-readelf}
70
71DWZ=${DWZ:-dwz}
72DWP=${DWP:-dwp}
73
74have_link=unknown
75next_is_output_file=no
76output_file=a.out
77
78want_index=false
79want_dwz=false
80want_multi=false
81want_dwp=false
82want_objcopy_compress=false
83
84while [ $# -gt 0 ]; do
85    case "$1" in
86	-Z) want_objcopy_compress=true ;;
87	-z) want_dwz=true ;;
88	-i) want_index=true ;;
89	-m) want_multi=true ;;
90	-p) want_dwp=true ;;
91	*) break ;;
92    esac
93    shift
94done
95
96for arg in "$@"
97do
98    if [ "$next_is_output_file" = "yes" ]
99    then
100	output_file="$arg"
101	next_is_output_file=no
102	continue
103    fi
104
105    # Poor man's gcc argument parser.
106    # We don't need to handle all arguments, we just need to know if we're
107    # doing a link and what the output file is.
108    # It's not perfect, but it seems to work well enough for the task at hand.
109    case "$arg" in
110    "-c") have_link=no ;;
111    "-E") have_link=no ;;
112    "-S") have_link=no ;;
113    "-o") next_is_output_file=yes ;;
114    esac
115done
116
117if [ "$next_is_output_file" = "yes" ]
118then
119    echo "$myname: Unable to find output file" >&2
120    exit 1
121fi
122
123if [ "$have_link" = "no" ]
124then
125    "$@"
126    exit $?
127fi
128
129index_file="${output_file}.gdb-index"
130if [ "$want_index" = true ] && [ -f "$index_file" ]
131then
132    echo "$myname: Index file $index_file exists, won't clobber." >&2
133    exit 1
134fi
135
136output_dir="${output_file%/*}"
137[ "$output_dir" = "$output_file" ] && output_dir="."
138
139"$@"
140rc=$?
141[ $rc != 0 ] && exit $rc
142if [ ! -f "$output_file" ]
143then
144    echo "$myname: Internal error: $output_file missing." >&2
145    exit 1
146fi
147
148if [ "$want_objcopy_compress" = true ]; then
149    $OBJCOPY --compress-debug-sections "$output_file"
150    rc=$?
151    [ $rc != 0 ] && exit $rc
152fi
153
154if [ "$want_index" = true ]; then
155    $GDB --batch-silent -nx -ex "set auto-load no" -ex "file $output_file" -ex "save gdb-index $output_dir"
156    rc=$?
157    [ $rc != 0 ] && exit $rc
158
159    # GDB might not always create an index.  Cope.
160    if [ -f "$index_file" ]
161    then
162	$OBJCOPY --add-section .gdb_index="$index_file" \
163	    --set-section-flags .gdb_index=readonly \
164	    "$output_file" "$output_file"
165	rc=$?
166    else
167	rc=0
168    fi
169    [ $rc != 0 ] && exit $rc
170fi
171
172if [ "$want_dwz" = true ]; then
173    $DWZ "$output_file" > /dev/null 2>&1
174elif [ "$want_multi" = true ]; then
175    cp $output_file ${output_file}.alt
176    $DWZ -m ${output_file}.dwz "$output_file" ${output_file}.alt > /dev/null 2>&1
177fi
178
179if [ "$want_dwp" = true ]; then
180    dwo_files=$($READELF -wi "${output_file}" | grep _dwo_name | \
181	sed -e 's/^.*: //' | sort | uniq)
182    rc=0
183    if [ -n "$dwo_files" ]; then
184	$DWP -o "${output_file}.dwp" ${dwo_files} > /dev/null
185	rc=$?
186	[ $rc != 0 ] && exit $rc
187	rm -f ${dwo_files}
188    fi
189fi
190
191rm -f "$index_file"
192exit $rc
193