contrib/compare-lto

   1 #! /bin/sh
   2
   3 # Compare copies of two given object files.
   4
   5 # Copyright (C) 2007-2024 Free Software Foundation, Inc.
   6 # Originally by Alexandre Oliva <aoliva@redhat.com>
   7 # Modified for LTO bootstrap by Richard Biener <rguenther@suse.de>
   8
   9 # This file is part of GCC.
  10
  11 # GCC is free software; you can redistribute it and/or modify it under
  12 # the terms of the GNU General Public License as published by the Free
  13 # Software Foundation; either version 3, or (at your option) any later
  14 # version.
  15
  16 # GCC is distributed in the hope that it will be useful, but WITHOUT
  17 # ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  18 # or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public
  19 # License for more details.
  20
  21 # You should have received a copy of the GNU General Public License
  22 # along with GCC; see the file COPYING3.  If not see
  23 # <http://www.gnu.org/licenses/>.
  24
  25 rm='rm -f'
  26
  27 case $1 in
  28 -p | --preserve)
  29   rm='echo preserving'
  30   shift
  31   ;;
  32 esac
  33
  34 if test $# != 2; then
  35   echo 'usage: compare-lto file1 file2' >&2
  36   exit 1
  37 fi
  38
  39 if test ! -f "$1"; then
  40   echo "$1" does not exist >&2
  41   exit 1
  42 fi
  43
  44 if test ! -f "$2"; then
  45   echo "$2" does not exist >&2
  46   exit 1
  47 fi
  48
  49 suf1=stripped
  50 while test -f "$1.$suf1"; do
  51   suf1=$suf1.
  52 done
  53
  54 suf2=stripped
  55 while test -f "$2.$suf2"; do
  56   suf2=$suf2.
  57 done
  58
  59 trap 'rm -f "$1.$suf1" "$2.$suf2"' 0 1 2 15
  60
  61 if cmp "$1" "$2"; then
  62   status=0
  63 else
  64   status=1
  65
  66   cmd=
  67   for t in objdump readelf eu-readelf; do
  68     if ($t --help) 2>&1 | grep ' --\[*section-\]*headers' > /dev/null; then
  69       cmd=$t
  70       break
  71     fi
  72   done
  73
  74   # If there are LTO option sections, try to strip them off.
  75   if test "x$cmd" = "x" ||
  76      $cmd --section-headers "$1" | grep '.gnu.lto_.opts' > /dev/null ||
  77      $cmd --section-headers "$2" | grep '.gnu.lto_.opts' > /dev/null ; then
  78
  79     echo stripping off LTO option section, then retrying >&2
  80
  81     seclist=".gnu.lto_.opts"
  82     rsopts=`for sec in $seclist; do echo " --remove-section $sec"; done`
  83
  84     if (objcopy -v) 2>&1 | grep ' --remove-section' > /dev/null; then
  85       objcopy $rsopts "$1" "$1.$suf1"
  86       objcopy $rsopts "$2" "$2.$suf2"
  87     elif (strip --help) 2>&1 | grep ' --remove-section' > /dev/null; then
  88       cp "$1" "$1.$suf1"
  89       strip $rsopts "$1.$suf1"
  90
  91       cp "$2" "$2.$suf2"
  92       strip $rsopts "$2.$suf2"
  93     else
  94       echo failed to strip off LTO option section >&2
  95     fi
  96
  97     trap 'rm -f "$1.$suf1" "$2.$suf2"' 0 1 2 15
  98
  99     if cmp "$1.$suf1" "$2.$suf2"; then
 100       status=0
 101     else
 102       status=1
 103     fi
 104
 105   # PE-COFF executables are timestamped so skip leading bytes for them.
 106   else
 107     case "$1" in
 108       *.exe)
 109         if cmp -i 256 "$1" "$2"; then
 110           status=0
 111         else
 112           status=1
 113         fi
 114         ;;
 115       *)
 116         if test -f "$1.exe" && cmp -i 256 "$1.exe" "$2.exe"; then
 117           status=0
 118         else
 119           status=1
 120         fi
 121         ;;
 122     esac
 123   fi
 124 fi
 125
 126 $rm "$1.$suf1" "$2.$suf2"
 127
 128 trap "exit $status; exit" 0 1 2 15
 129
 130 exit $status