gcc/gcc/genmultilib

#!/bin/sh 
# Generates multilib.h.
#   Copyright (C) 1994-2017 Free Software Foundation, Inc.

#This file is part of GCC.

#GCC 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, or (at your option) any later
#version.

#GCC 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 GCC; see the file COPYING3.  If not see
#<http://www.gnu.org/licenses/>.  

# This shell script produces a header file which the gcc driver
# program uses to pick which library to use based on the machine
# specific options that it is given.

# The first argument is a list of sets of options.  The elements in
# the list are separated by spaces.  Within an element, the options
# are separated by slashes or pipes.  No leading dash is used on the
# options.
# Each option in a set separated by slashes is mutually incompatible
# with all other options
# in the set.
# Each option in a set separated by pipes will be used for the library
# compilation and any of the options in the set will be sufficient
# for it to be triggered.

# The optional second argument is a list of subdirectory names.  If
# the second argument is non-empty, there must be as many elements in
# the second argument as there are options in the first argument.  The
# elements in the second list are separated by spaces.  If the second
# argument is empty, the option names will be used as the directory
# names.

# The optional third argument is a list of options which are
# identical.  The elements in the list are separated by spaces.  Each
# element must be of the form OPTION=OPTION.  The first OPTION should
# appear in the first argument, and the second should be a synonym for
# it.  Question marks are replaced with equal signs in both options.

# The optional fourth argument is a list of multilib directory 
# combinations that should not be built.

# The optional fifth argument is a list of options that should be
# used whenever building multilib libraries.

# The optional sixth argument is a list of exclusions used internally by
# the compiler similar to exceptions. The difference being that exclusions
# allow matching default options that genmultilib does not know about and
# is done at runtime as opposed to being sorted out at compile time.
# Each element in the list is a separate exclusion rule. Each rule is
# a list of options (sans preceding '-') separated by a '/'. The options
# on the rule are grouped as an AND operation, and all options much match
# for the rule to exclude a set. Options can be preceded with a '!' to
# match a logical NOT.

# The optional seventh argument is a list of OS subdirectory names.
# The format is either the same as of the second argument, or a set of
# mappings. When it is the same as the second argument, it describes
# the multilib directories using OS conventions, rather than GCC
# conventions.  When it is a set of mappings of the form gccdir=osdir,
# the left side gives the GCC convention and the right gives the
# equivalent OS defined location.  If the osdir part begins with a !,
# the os directory names are used exclusively.  Use the mapping when
# there is no one-to-one equivalence between GCC levels and the OS.

# The optional eighth argument which intends to reduce the effort to write
# so many MULTILIB_EXCEPTIONS rules. This option defines a series of option
# combinations that we actually required.
# For some cases, the generated option combinations are far more than what
# we need, we have to write a lot of rules to screen out combinations we
# don't need. If we missed some rules, the unexpected libraries will be built.
# Now with this argument, one can simply give what combinations are needed.
# It is pretty straigtforward.
# This argument can be used together with MULTILIB_EXCEPTIONS and will take
# effect after the MULTILIB_EXCEPTIONS.

# The optional ninth argument is the multiarch name.

# The optional tenth argument specifies how to reuse multilib for different
# option sets.

# The last option should be "yes" if multilibs are enabled.  If it is not
# "yes", all GCC multilib dir names will be ".".

# The output looks like
#   #define MULTILIB_MATCHES "\
#   SUBDIRECTORY OPTIONS;\
#   ...
#   "
# The SUBDIRECTORY is the subdirectory to use.  The OPTIONS are
# multiple options separated by spaces.  Each option may start with an
# exclamation point.  gcc will consider each line in turn.  If none of
# the options beginning with an exclamation point are present, and all
# of the other options are present, that subdirectory will be used.
# The order of the subdirectories is such that they can be created in
# order; that is, a subdirectory is preceded by all its parents.

# Here is an example (this is from the actual sparc64 case):
#   genmultilib 'm64/m32 mno-app-regs|mcmodel=medany' '64 32 alt'
#		'mcmodel?medany=mcmodel?medmid' 'm32/mno-app-regs* m32/mcmodel=*'
#		'' 'm32/!m64/mno-app-regs m32/!m64/mcmodel=medany'
#		'../lib64 ../lib32 alt' '' '' '' yes
# This produces:
#   ". !m64 !m32 !mno-app-regs !mcmodel=medany;",
#   "64:../lib64 m64 !m32 !mno-app-regs !mcmodel=medany;",
#   "32:../lib32 !m64 m32 !mno-app-regs !mcmodel=medany;",
#   "alt !m64 !m32 mno-app-regs mcmodel=medany;",
#   "alt !m64 !m32 mno-app-regs !mcmodel=medany;",
#   "alt !m64 !m32 !mno-app-regs mcmodel=medany;",
#   "64/alt:../lib64/alt m64 !m32 mno-app-regs mcmodel=medany;",
#   "64/alt:../lib64/alt m64 !m32 mno-app-regs !mcmodel=medany;",
#   "64/alt:../lib64/alt m64 !m32 !mno-app-regs mcmodel=medany;",
#
# The effect is that `gcc -mno-app-regs' (for example) will append "alt"
# to the directory name when searching for libraries or startup files and
# `gcc -m32 -mcmodel=medany' (for example) will append "32/alt". Also note
# that exclusion above is moot, unless the compiler had a default of -m32,
# which would mean that all of the "alt" directories (not the 64/alt ones)
# would be ignored (not generated, nor used) since the exclusion also
# matches the multilib_default args.

# Copy the positional parameters into variables.
options=$1
dirnames=$2
matches=$3
exceptions=$4
extra=$5
exclusions=$6
osdirnames=$7
multilib_required=$8
multiarch=$9
multilib_reuse=${10}
enable_multilib=${11}

echo "static const char *const multilib_raw[] = {"

mkdir tmpmultilib.$$ || exit 1
# Use cd ./foo to avoid CDPATH output.
cd ./tmpmultilib.$$ || exit 1

# What we want to do is select all combinations of the sets in
# options.  Each combination which includes a set of mutually
# exclusive options must then be output multiple times, once for each
# item in the set.  Selecting combinations is a recursive process.
# Since not all versions of sh support functions, we achieve recursion
# by creating a temporary shell script which invokes itself.
rm -f tmpmultilib
cat >tmpmultilib <<\EOF
#!/bin/sh
# This recursive script basically outputs all combinations of its
# input arguments, handling mutually exclusive sets of options by
# repetition.  When the script is called, ${initial} is the list of
# options which should appear before all combinations this will
# output.  The output looks like a list of subdirectory names with
# leading and trailing slashes.
if [ "$#" != "0" ]; then
  first=$1
  shift
  case "$first" in
  *\|*)
    all=${initial}`echo $first | sed -e 's_|_/_'g`
    first=`echo $first | sed -e 's_|_ _'g`
    echo ${all}/
    initial="${initial}${all}/" ./tmpmultilib $@
    ./tmpmultilib $first $@ | grep -v "^${all}"
    ;;
  *)
    for opt in `echo $first | sed -e 's|/| |'g`; do
      echo ${initial}${opt}/
    done
    ./tmpmultilib $@
    for opt in `echo $first | sed -e 's|/| |'g`; do
      initial="${initial}${opt}/" ./tmpmultilib $@
    done
  esac
fi
EOF
chmod +x tmpmultilib

combination_space=`initial=/ ./tmpmultilib ${options}`
combinations="$combination_space"

# If there exceptions, weed them out now
if [ -n "${exceptions}" ]; then
  cat >tmpmultilib2 <<\EOF
#!/bin/sh
# This recursive script weeds out any combination of multilib
# switches that should not be generated.  The output looks like
# a list of subdirectory names with leading and trailing slashes.

  for opt in $@; do
    case "$opt" in
EOF

  for except in ${exceptions}; do
    echo "      /${except}/) : ;;" >> tmpmultilib2
  done

cat >>tmpmultilib2 <<\EOF
      *) echo ${opt};;
    esac
  done
EOF
  chmod +x tmpmultilib2
  combinations=`./tmpmultilib2 ${combinations}`
fi

# If the MULTILIB_REQUIRED list are provided,
# filter out combinations not in this list.
if [ -n "${multilib_required}" ]; then
  cat >tmpmultilib2 <<\EOF
#!/bin/sh
# This recursive script weeds out any combination of multilib
# switches that not in the expected list.

  for opt in $@; do
    case "$opt" in
EOF

  for expect in ${multilib_required}; do
    echo "      /${expect}/) echo \${opt};;" >> tmpmultilib2
  done

cat >>tmpmultilib2 <<\EOF
      *) ;;
    esac
  done
EOF

   chmod +x tmpmultilib2
   combinations=`./tmpmultilib2 ${combinations}`

fi

# Construct a sed pattern which will convert option names to directory
# names.
todirnames=
if [ -n "${dirnames}" ]; then
  set x ${dirnames}
  shift
  for set in ${options}; do
    for opts in `echo ${set} | sed -e 's|/| |'g`; do
      patt="/"
      for opt in `echo ${opts} | sed -e 's_|_ _'g`; do
        if [ "$1" != "${opt}" ]; then
          todirnames="${todirnames} -e s|/${opt}/|/${1}/|g"
	  patt="${patt}${1}/"
	  if [ "${patt}" != "/${1}/" ]; then
	    todirnames="${todirnames} -e s|${patt}|/${1}/|g"
          fi
        fi
      done
      shift
    done
  done
fi

# Construct a sed pattern which will convert option names to OS directory
# names.
toosdirnames=
defaultosdirname=
defaultosdirname2=
if [ -n "${multiarch}" ]; then
  defaultosdirname=::${multiarch}
fi
if [ -n "${osdirnames}" ]; then
  set x ${osdirnames}
  shift
  while [ $# != 0 ] ; do
    case "$1" in
      .=*)
        defaultosdirname=`echo $1 | sed 's|^.=|:|'`
	if [ -n "${multiarch}" ]; then
	  defaultosdirname=${defaultosdirname}:${multiarch}
	fi
	case "$defaultosdirname" in
	  ::*) ;;
	  *)
	    defaultosdirname2=${defaultosdirname}
	    defaultosdirname=
	    ;;
	esac
	shift
	;;
      *=*)
	patt=`echo $1 | sed -e 's|=|/$=/|'`
        toosdirnames="${toosdirnames} -e s=^/${patt}/="
	shift
        ;;
      *)
        break
	;;
    esac
  done
  
  if [ $# != 0 ]; then
    for set in ${options}; do
      for opts in `echo ${set} | sed -e 's|/| |'g`; do
        patt="/"
        for opt in `echo ${opts} | sed -e 's_|_ _'g`; do
          if [ "$1" != "${opt}" ]; then
            toosdirnames="${toosdirnames} -e s|/${opt}/|/${1}/|g"
	    patt="${patt}${1}/"
	    if [ "${patt}" != "/${1}/" ]; then
	      toosdirnames="${toosdirnames} -e s|${patt}|/${1}/|g"
            fi
          fi
        done
        shift
      done
    done
  fi
fi

# We need another recursive shell script to correctly handle positive
# matches.  If we are invoked as
#   genmultilib "opt1 opt2" "" "opt1=nopt1 opt2=nopt2"
# we must output
#   opt1/opt2 opt1 opt2
#   opt1/opt2 nopt1 opt2
#   opt1/opt2 opt1 nopt2
#   opt1/opt2 nopt1 nopt2
# In other words, we must output all combinations of matches.
rm -f tmpmultilib2
cat >tmpmultilib2 <<\EOF
#!/bin/sh
# The positional parameters are a list of matches to consider.
# ${dirout} is the directory name and ${optout} is the current list of
# options.
if [ "$#" = "0" ]; then
  echo "\"${dirout} ${optout};\","
else
  first=$1
  shift
  dirout="${dirout}" optout="${optout}" ./tmpmultilib2 $@
  l=`echo ${first} | sed -e 's/=.*$//' -e 's/?/=/g'`
  r=`echo ${first} | sed -e 's/^.*=//' -e 's/?/=/g'`
  if expr " ${optout} " : ".* ${l} .*" > /dev/null; then
    newopt=`echo " ${optout} " | sed -e "s/ ${l} / ${r} /" -e 's/^ //' -e 's/ $//'`
    dirout="${dirout}" optout="${newopt}" ./tmpmultilib2 $@
  fi
fi
EOF
chmod +x tmpmultilib2

# Start with the current directory, which includes only negations.
optout=
for set in ${options}; do
  for opt in `echo ${set} | sed -e 's_[/|]_ _g'`; do
    optout="${optout} !${opt}"
  done
done
optout=`echo ${optout} | sed -e 's/^ //'`
echo "\".${defaultosdirname} ${optout};\","
[ -n "${defaultosdirname2}" ] && echo "\".${defaultosdirname2} ${optout};\","

# This part of code convert an option combination to
# its corresponding directory names.
# The directory names will be deduced from MULTILIB_DIRNAMES,
# MULTILIB_OSDIRNAMES or the option combination itself.
rm -rf tmpmultilib3
cat >tmpmultilib3 <<\EOF
#!/bin/sh

dirout=
combo=$1
todirnames=$2
toosdirnames=$3
enable_multilib=$4

if [ -n "${todirnames}" ]; then
  dirout=`echo ${combo} | sed ${todirnames}`
else
  dirout=`echo ${combo} | sed -e 's/=/-/g'`
fi
# Remove the leading and trailing slashes.
dirout=`echo ${dirout} | sed -e 's|^/||' -e 's|/*:/*|:|' -e 's|/$||g'`

# Use the OS directory names rather than the option names.
if [ -n "${toosdirnames}" ]; then
  osdirout=`echo ${combo} | sed ${toosdirnames}`
  # Remove the leading and trailing slashes.
  osdirout=`echo ${osdirout} | sed -e 's|^/||' -e 's|/*:/*|:|' -e 's|/$||g'`
  if [ "x${enable_multilib}" != xyes ]; then
    dirout=".:${osdirout}"
    disable_multilib=yes
  else
    case "${osdirout}" in
      !*)
	dirout=`echo ${osdirout} | sed 's/^!//'`
	;;
       *)
	dirout="${dirout}:${osdirout}"
	;;
    esac
  fi
else
  if [ "x${enable_multilib}" != xyes ]; then
    # genmultilib with --disable-multilib should be
    # called with '' '' '' '' '' '' '' no
    # if MULTILIB_OSDIRNAMES is empty.
    exit 1
  fi
fi
echo "${dirout}"
EOF
chmod +x tmpmultilib3

# Script to look through the options and output each option that is present,
# and negate each option that is not present.
rm -rf tmpmultilib4
cat > tmpmultilib4 <<\EOF
#!/bin/sh

optout=
combo=$1
options=$2

for set in ${options}; do
  setopts=`echo ${set} | sed -e 's_[/|]_ _g'`
  for opt in ${setopts}; do
    if expr "${combo} " : ".*/${opt}/.*" > /dev/null; then
      optout="${optout} ${opt}"
    else
      optout="${optout} !${opt}"
    fi
  done
done
optout=`echo ${optout} | sed -e 's/^ //'`
echo "${optout}"
EOF
chmod +x tmpmultilib4

# Work over the list of combinations.  We have to translate each one
# to use the directory names rather than the option names, we have to
# include the information in matches, and we have to generate the
# correct list of options and negations.
for combo in ${combinations}; do
  # Use the directory names rather than the option names.
  dirout=`./tmpmultilib3 "${combo}" "${todirnames}" "${toosdirnames}" "${enable_multilib}"`

  # Look through the options.  We must output each option that is
  # present, and negate each option that is not present.
  optout=`./tmpmultilib4 "${combo}" "${options}"`

  # Output the line with all appropriate matches.
  dirout="${dirout}" optout="${optout}" ./tmpmultilib2
done

# Terminate the list of string.
echo "NULL"
echo "};"

# Output rules used for multilib reuse.
echo ""
echo "static const char *const multilib_reuse_raw[] = {"
for rrule in ${multilib_reuse}; do
  # The left part of the rule are the options we used to build multilib.
  # The right part of the rule are the options that can reuse this multilib.
  combo=`echo ${rrule} | sed -e 's/=.*$//' -e 's/\./=/g'`
  copts=`echo ${rrule} | sed -e 's/^.*=//' -e 's/\./=/g'`
  # The variable ${combinations} are the option combinations we will build
  # multilib from.  If the combination in the left part of reuse rule isn't
  # in this variable, it means no multilib will be built for current reuse
  # rule.  Thus the reuse purpose specified by current rule is meaningless.
  if expr "${combinations} " : ".*/${combo}/.*" > /dev/null; then
    if expr "${combination_space} " : ".*/${copts}/.*" > /dev/null; then
      combo="/${combo}/"
      dirout=`./tmpmultilib3 "${combo}" "${todirnames}" "${toosdirnames}" "${enable_multilib}"`
      copts="/${copts}/"
      optout=`./tmpmultilib4 "${copts}" "${options}"`
      # Output the line with all appropriate matches.
      dirout="${dirout}" optout="${optout}" ./tmpmultilib2
    else
      echo "The rule ${rrule} contains an option absent from MULTILIB_OPTIONS." >&2
      exit 1
    fi
  else
    echo "The rule ${rrule} is trying to reuse nonexistent multilib." >&2
    exit 1
  fi
done

# Terminate the list of string.
echo "NULL"
echo "};"

# Output all of the matches now as option and that is the same as that, with
# a semicolon trailer.  Include all of the normal options as well.
# Note, the format of the matches is reversed compared
# to what we want, so switch them around.
echo ""
echo "static const char *const multilib_matches_raw[] = {"
for match in ${matches}; do
  l=`echo ${match} | sed -e 's/=.*$//' -e 's/?/=/g'`
  r=`echo ${match} | sed -e 's/^.*=//' -e 's/?/=/g'`
  echo "\"${r} ${l};\","
done
for set in ${options}; do
  for opt in `echo ${set} | sed -e 's_[/|]_ _'g`; do
    echo "\"${opt} ${opt};\","
  done
done
echo "NULL"
echo "};"

# Output the default options now
echo ""
echo "static const char *multilib_extra = \"${extra}\";"

# Output the exclusion rules now
echo ""
echo "static const char *const multilib_exclusions_raw[] = {"
for rule in ${exclusions}; do
  s=`echo ${rule} | sed -e 's,/, ,g'`
  echo "\"${s};\","
done
echo "NULL"
echo "};"

# Output the options now
moptions=`echo ${options} | sed -e 's,[ 	][ 	]*, ,g'`
echo ""
echo "static const char *multilib_options = \"${moptions}\";"

# Finally output the disable flag if specified
if [ "x${disable_multilib}" = xyes ]; then
  echo ""
  echo "#define DISABLE_MULTILIB  1"
fi

cd ..
rm -r tmpmultilib.$$

exit 0