#! /bin/sh
#---------------------------------------------------------------------------#
# Copyright (C) 1996 The University of Melbourne.
# This file may only be copied under the terms of the GNU General
# Public License - see the file COPYING in the Mercury distribution.
#---------------------------------------------------------------------------#
#
# The purpose of this file is to work around a bug in gcc and/or `as'
# on AIX RS/6000.  The bug is that `as' complains about an offset
# being greater than +/- 32k.  The work-around is to chop large
# files into smaller bits.

# specify the maximum number of C source lines that we think gcc/as can handle
max_lines=10000

# specify the names of the files which gcc/as can't handle
files_to_fix="make_hlds.c prog_io.c"

#-----------------------------------------------------------------------------#

echo finding small files
files_to_use="`wc -l *.c | sort -n | grep -v total | grep -v _init |
		awk '{print $2;}'`"
#echo files_to_use=$files_to_use

# When we move bits, we need to make them external, rather than
# static
fixup="sed -e /^Declare_static/s//Declare_entry/ 
-e /^Define_static/s//Define_entry/"

set - $files_to_use
for file in $files_to_fix; do
	num_lines=`wc -l $file | awk '{print $1;}'`
	num_extra_pieces=`expr $num_lines / $max_lines`
	echo splitting $num_extra_pieces pieces off $file
	piece=1
	while [ $piece -le $num_extra_pieces ]; do
		echo splitting piece number $piece into $1
		first_line=`expr $piece "*" $max_lines`
		last_line=`expr $piece "*" $max_lines + $max_lines`
		v1='$1'
		export v1
		if [ $piece = 1 ]; then
		    #
		    # start at a Declare_... or Define_extern_entry...
		    #
		    begin_line=`
			egrep -n '^(Define_extern_entry|Declare)' $file |
			awk -F: "$v1 >= $first_line { print $v1; exit(0); }"
			`
		else
		   #
		   # start just after where we left off
		   #
			begin_line=`expr $end_line + 1`
		fi
		echo begin_line=$begin_line
		#
		# stop at an END_MODULE
		#
		end_line=`
			grep -n '^END_MODULE' $file |
			awk -F: "$v1 < $last_line { el = $v1; }
				END { print el; }"
			`
		echo end_line=$end_line
		len=`expr $end_line - $begin_line + 1`
		echo len=$len
		cp $1 $1.new
		tail +$begin_line $file | head -$len | $fixup >> $1.new
		mv $1 $1.old
		mv $1.new $1
		rm -f `basename $1 .c`.o
		if [ $piece = 1 ]; then
			head_count=`expr $begin_line - 1`
		fi
		tail_count=`expr $end_line + 1` 
		shift
		piece=`expr $piece + 1`
	done
	echo fixing $file
	head -$head_count $file | $fixup > $file.new
	tail +$tail_count $file | $fixup >> $file.new
	mv $file $file.old
	mv $file.new $file
	rm -f `basename $file .c`.o
done