glibc/sysdeps/i386/tst-ld-sse-use.sh

#!/bin/bash
# Make sure no code in ld.so uses xmm/ymm/zmm registers on i386.
# Copyright (C) 2009-2024 Free Software Foundation, Inc.
# This file is part of the GNU C Library.

# The GNU C Library is free software; you can redistribute it and/or
# modify it under the terms of the GNU Lesser General Public
# License as published by the Free Software Foundation; either
# version 2.1 of the License, or (at your option) any later version.

# The GNU C Library 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
# Lesser General Public License for more details.

# You should have received a copy of the GNU Lesser General Public
# License along with the GNU C Library; if not, see
# <https://www.gnu.org/licenses/>.

set -e

objpfx="$1"
NM="$2"
OBJDUMP="$3"
READELF="$4"

tmp=$(mktemp ${objpfx}tst-ld-sse-use.XXXXXX)
trap 'rm -f "$tmp"' 1 2 3 15

# List of object files we have to test
rtldobjs=$($READELF -W -wi ${objpfx}dl-allobjs.os |
    awk '/^ </ { if ($5 == "(DW_TAG_compile_unit)") c=1; else c=0 } $2 == "DW_AT_name" { if (c == 1) print $NF }' |
    sed 's,\(.*/\|\)\([_[:alnum:]-]*[.]\).$,\2os,')
rtldobjs="$rtldobjs $(ar t ${objpfx}rtld-libc.a)"

# OBJECT symbols can be ignored.
$READELF -sW ${objpfx}dl-allobjs.os ${objpfx}rtld-libc.a |
grep -E " OBJECT  *GLOBAL " |
awk '{if ($7 != "ABS") print $8 }' |
sort -u > "$tmp"
declare -a objects
objects=($(cat "$tmp"))

objs="dl-runtime.os"
tocheck="dl-runtime.os"

while test -n "$objs"; do
  this="$objs"
  objs=""

  for f in $this; do
    undef=$($NM -u "$objpfx"../*/"$f" | awk '{print $2}')
    if test -n "$undef"; then
      for s in $undef; do
	for obj in ${objects[*]} "_GLOBAL_OFFSET_TABLE_"; do
	  if test "$obj" = "$s"; then
	    continue 2
	  fi
	done
        for o in $rtldobjs; do
	  ro=$(echo "$objpfx"../*/"$o")
	  if $NM -g --defined-only "$ro" | grep -E -qs " $s\$"; then
	    if ! (echo "$tocheck $objs" | grep -F -qs "$o"); then
	      echo "$o needed for $s"
	      objs="$objs $o"
	    fi
	    break;
	  fi
	done
      done
    fi
  done
  tocheck="$tocheck$objs"
done

echo
echo
echo "object files needed: $tocheck"

cp /dev/null "$tmp"
for f in $tocheck; do
  $OBJDUMP -d "$objpfx"../*/"$f" |
  awk 'BEGIN { last="" } /^[[:xdigit:]]* <[_[:alnum:]]*>:$/ { fct=substr($2, 2, length($2)-3) } /,%[xyz]mm[[:digit:]]*$/ { if (last != fct) { print fct; last=fct} }' |
  while read fct; do
    if test "$fct" = "_dl_runtime_profile" -o "$fct" = "_dl_x86_64_restore_sse"; then
      continue;
    fi
    echo "function $fct in $f modifies xmm/ymm/zmm" >> "$tmp"
    result=1
  done
done

if test -s "$tmp"; then
  echo
  echo
  cat "$tmp"
  result=1
else
  result=0
fi

rm "$tmp"
exit $result