@code{MULTILIB_OPTIONS} will be filtered by @code{MULTILIB_EXCEPTIONS}
and then by @code{MULTILIB_REQUIRED}.
+@findex MULTILIB_REUSE
+@item MULTILIB_REUSE
+Sometimes it is desirable to reuse one existing multilib for different
+sets of options. Such kind of reuse can minimize the number of multilib
+variants. And for some targets it is better to reuse an existing multilib
+than to fall back to default multilib when there is no corresponding multilib.
+This can be done by adding reuse rules to @code{MULTILIB_REUSE}.
+
+A reuse rule is comprised of two parts connected by equality sign. The left part
+is option set used to build multilib and the right part is option set that will
+reuse this multilib. The order of options in the left part matters and should be
+same with those specified in @code{MULTILIB_REQUIRED} or aligned with order in
+@code{MULTILIB_OPTIONS}. There is no such limitation for options in right part
+as we don't build multilib from them. But the equality sign in both parts should
+be replaced with period.
+
+The @code{MULTILIB_REUSE} is different from @code{MULTILIB_MATCHES} in that it
+sets up relations between two option sets rather than two options. Here is an
+example to demo how we reuse libraries built in Thumb mode for applications built
+in ARM mode:
+@smallexample
+@code{MULTILIB_REUSE} = mthumb/march.armv7-r=marm/march.armv7-r
+@end smallexample
+
+Before the advent of @code{MULTILIB_REUSE}, GCC select multilib by comparing command
+line options with options used to build multilib. The @code{MULTILIB_REUSE} is
+complementary to that way. Only when the original comparison matches nothing it will
+work to see if it is OK to reuse some existing multilib.
+
@findex MULTILIB_EXTRA_OPTS
@item MULTILIB_EXTRA_OPTS
Sometimes it is desirable that when building multiple versions of
static const char *multilib_matches;
static const char *multilib_defaults;
static const char *multilib_exclusions;
+static const char *multilib_reuse;
/* Check whether a particular argument is a default argument. */
INIT_STATIC_SPEC ("multilib_matches", &multilib_matches),
INIT_STATIC_SPEC ("multilib_exclusions", &multilib_exclusions),
INIT_STATIC_SPEC ("multilib_options", &multilib_options),
+ INIT_STATIC_SPEC ("multilib_reuse", &multilib_reuse),
INIT_STATIC_SPEC ("linker", &linker_name_spec),
INIT_STATIC_SPEC ("linker_plugin_file", &linker_plugin_file_spec),
INIT_STATIC_SPEC ("lto_wrapper", <o_wrapper_spec),
obstack_1grow (&multilib_obstack, 0);
multilib_exclusions = XOBFINISH (&multilib_obstack, const char *);
+ q = multilib_reuse_raw;
+ while ((p = *q++) != (char *) 0)
+ obstack_grow (&multilib_obstack, p, strlen (p));
+
+ obstack_1grow (&multilib_obstack, 0);
+ multilib_reuse = XOBFINISH (&multilib_obstack, const char *);
+
need_space = FALSE;
for (i = 0; i < ARRAY_SIZE (multilib_defaults_raw); i++)
{
first = 1;
p = multilib_select;
+
+ /* Append multilib reuse rules if any. With those rules, we can reuse
+ one multilib for certain different options sets. */
+ if (strlen (multilib_reuse) > 0)
+ p = concat (p, multilib_reuse, NULL);
+
while (*p != '\0')
{
/* Ignore newlines. */
if (*p == '\0')
{
invalid_select:
- fatal_error ("multilib select %qs is invalid",
- multilib_select);
+ fatal_error ("multilib select %qs %qs is invalid",
+ multilib_select, multilib_reuse);
}
++p;
}
# 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 ".".
# 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
+# '../lib64 ../lib32 alt' '' '' '' yes
# This produces:
# ". !m64 !m32 !mno-app-regs !mcmodel=medany;",
# "64:../lib64 m64 !m32 !mno-app-regs !mcmodel=medany;",
osdirnames=$7
multilib_required=$8
multiarch=$9
-enable_multilib=${10}
+multilib_reuse=${10}
+enable_multilib=${11}
echo "static const char *const multilib_raw[] = {"
optout=`echo ${optout} | sed -e 's/^ //'`
echo "\".${defaultosdirname} ${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 ${combinations}; do
# Use the directory names rather than the option names.
- if [ -n "${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
+ 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=
- 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 ${optout} | sed -e 's/^ //'`
+ optout=`./tmpmultilib4 "${combo}" "${options}"`
# Output the line with all appropriate matches.
dirout="${dirout}" optout="${optout}" ./tmpmultilib2
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} " : ".*/${combo}/.*" > /dev/null; then
+ combo="/${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} is trying to reuse nonexistent multilib."
+ 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