sim: drop mention of & support for subdir configure

Now that no ports use these common configure APIs, delete the logic
and remove it from the documentation.

sim/README-HACKING

@@ -31,24 +31,6 @@ in configure.ac and Makefile.in, and it also provides a foundation for
 enhancing the simulators uniformly (e.g. the more they share in common
 the easier a feature added to one is added to all).
 
-The configure.ac of a simulator using the common framework should look like:
-
---- snip ---
-dnl Process this file with autoconf to produce a configure script.
-AC_INIT(Makefile.in)
-AC_CONFIG_MACRO_DIRS([../common ../.. ../../config])
-
-... target specific additions ...
-
-SIM_AC_OUTPUT
---- snip ---
-
-SIM_AC_OUTPUT:
-
-- creates the symbolic links defined in sim_link_{files,links}
-- creates config.h
-- creates the Makefile
-
 The Makefile.in of a simulator using the common framework should look like:
 
 --- snip ---
@@ -81,7 +63,7 @@ SIM_EXTRA_CLEAN =
 ... target specific rules ...
 --- snip ---
 
-COMMON_{PRE,POST}_CONFIG_FRAG are markers for SIM_AC_OUTPUT to tell it
+COMMON_{PRE,POST}_CONFIG_FRAG are markers for configure to tell it
 where to insert the two pieces of common/Make-common.in.
 The resulting Makefile is created by doing autoconf substitions on
 both the target's Makefile.in and Make-common.in, and inserting
@@ -107,35 +89,7 @@ are greppable and appear in the TAGS file.
 Generating "configure" files
 ============================
 
-For targets using the common framework, "configure" can be generated
-by running `autoconf'.
-
-To regenerate the configure files for all targets using the common framework:
-
-	$  cd devo/sim
-	$  make -f Makefile.in SHELL=/bin/sh autoconf-common
-
-To add a change-log entry to the ChangeLog file for each updated
-directory (WARNING - check the modified new-ChangeLog files before
-renaming):
-
-	$  make -f Makefile.in SHELL=/bin/sh autoconf-changelog
-	$  more */new-ChangeLog
-	$  make -f Makefile.in SHELL=/bin/sh autoconf-install
-
-In a similar vein, both the configure and config.in files can be
-updated using the sequence:
-
-	$  cd devo/sim
-	$  make -f Makefile.in SHELL=/bin/sh autoheader-common
-	$  make -f Makefile.in SHELL=/bin/sh autoheader-changelog
-	$  more */new-ChangeLog
-	$  make -f Makefile.in SHELL=/bin/sh autoheader-install
-
-To add the entries to an alternative ChangeLog file, use:
-
-	$  make ChangeLog=MyChangeLog ....
-
+"configure" can be generated by running `autoreconf'.
 
 C Language Assumptions
 ======================

sim/m4/sim_ac_option_environment.m4

@@ -13,12 +13,6 @@ dnl
 dnl You should have received a copy of the GNU General Public License
 dnl along with this program.  If not, see <http://www.gnu.org/licenses/>.
 dnl
-dnl Additional SIM options that can (optionally) be configured
-dnl For optional simulator options, a macro SIM_AC_OPTION_* is defined.
-dnl Simulators that wish to use the relevant option specify the macro
-dnl in the simulator specific configure.ac file between the SIM_AC_COMMON
-dnl and SIM_AC_OUTPUT lines.
-dnl
 dnl Specify the running environment.
 dnl If the simulator invokes this in its configure.ac then without this option
 dnl the default is the user environment and all are runtime selectable.

sim/m4/sim_ac_output.m4

@@ -1,51 +0,0 @@
-dnl Copyright (C) 1997-2023 Free Software Foundation, Inc.
-dnl
-dnl This program is free software; you can redistribute it and/or modify
-dnl it under the terms of the GNU General Public License as published by
-dnl the Free Software Foundation; either version 3 of the License, or
-dnl (at your option) any later version.
-dnl
-dnl This program is distributed in the hope that it will be useful,
-dnl but WITHOUT ANY WARRANTY; without even the implied warranty of
-dnl MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-dnl GNU General Public License for more details.
-dnl
-dnl You should have received a copy of the GNU General Public License
-dnl along with this program.  If not, see <http://www.gnu.org/licenses/>.
-dnl
-dnl Generate the Makefile in a target specific directory.
-dnl Substitutions aren't performed on the file in AC_SUBST_FILE,
-dnl so this is a cover macro to tuck the details away of how we cope.
-dnl We cope by having autoconf generate two files and then merge them into
-dnl one afterwards.  The two pieces of the common fragment are inserted into
-dnl the target's fragment at the appropriate points.
-AC_DEFUN([SIM_AC_OUTPUT],
-[dnl
-AC_CONFIG_FILES(Makefile.sim:Makefile.in)
-AC_CONFIG_FILES(Make-common.sim:../common/Make-common.in)
-AC_CONFIG_COMMANDS([Makefile],
-[echo "Merging Makefile.sim+Make-common.sim into Makefile ..."
- rm -f Makesim1.tmp Makesim2.tmp Makefile
- sed -n -e '/^## COMMON_PRE_/,/^## End COMMON_PRE_/ p' <Make-common.sim >Makesim1.tmp
- sed -n -e '/^## COMMON_POST_/,/^## End COMMON_POST_/ p' <Make-common.sim >Makesim2.tmp
- sed -e '/^## COMMON_PRE_/ r Makesim1.tmp' \
-	-e '/^## COMMON_POST_/ r Makesim2.tmp' \
-	<Makefile.sim >Makefile
- rm -f Makefile.sim Make-common.sim Makesim1.tmp Makesim2.tmp
-])
-AC_CONFIG_COMMANDS([stamp-h], [echo > stamp-h])
-
-dnl These are unfortunate.  They are conditionally called by other sim macros
-dnl but always used by common/Make-common.in.  So we have to subst here even
-dnl when the rest of the code is in the respective macros.
-AC_SUBST(sim_bitsize)
-AC_SUBST(sim_float)
-
-dnl Used by common/Make-common.in to see which configure script created it.
-SIM_COMMON_BUILD_TRUE='#'
-SIM_COMMON_BUILD_FALSE=
-AC_SUBST(SIM_COMMON_BUILD_TRUE)
-AC_SUBST(SIM_COMMON_BUILD_FALSE)
-
-AC_OUTPUT
-])