You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
129 lines
5.1 KiB
129 lines
5.1 KiB
# floatparam.m4 serial 1
|
|
dnl Copyright (C) 2005 Free Software Foundation, Inc.
|
|
dnl This file is free software; the Free Software Foundation
|
|
dnl gives unlimited permission to copy and/or distribute it,
|
|
dnl with or without modifications, as long as this notice is preserved.
|
|
|
|
dnl From Bruno Haible.
|
|
|
|
AC_DEFUN([CL_FLOATPARAM_CROSS],
|
|
[
|
|
AC_REQUIRE([CL_LONGDOUBLE])
|
|
cl_machine_file_h=$1
|
|
{
|
|
echo "/* Rounding modes, for use below */"
|
|
echo "#define rounds_to_nearest 0 /* 0.5 ulp */"
|
|
echo "#define rounds_to_zero 1 /* 1 ulp */"
|
|
echo "#define rounds_to_infinity 2 /* 1 ulp */"
|
|
echo "#define rounds_to_minus_infinity 3 /* 1 ulp */"
|
|
echo
|
|
for type in float double "`if test $cl_cv_c_longdouble = yes; then echo 'long double'; fi`"; do
|
|
if test -n "$type"; then
|
|
epsilon_bits=-1; y="($type)1.0"
|
|
while true; do
|
|
AC_TRY_COMPILE([],
|
|
[typedef int verify[2*(
|
|
(($type)(($type)1.0 + ($type)($y)) == ($type)1.0)
|
|
|| ($type)(($type)(($type)1.0 + ($type)($y)) - ($type)1.0) != ($type)($y)
|
|
) - 1];],
|
|
[break;])
|
|
epsilon_bits=`expr $epsilon_bits + 1`; y="$y * ($type)0.5"
|
|
done
|
|
negepsilon_bits=-1; y="($type)-1.0"
|
|
while true; do
|
|
AC_TRY_COMPILE([],
|
|
[typedef int verify[2*(
|
|
(($type)(($type)1.0 + ($type)($y)) == ($type)1.0)
|
|
|| ($type)(($type)(($type)1.0 + ($type)($y)) - ($type)1.0) != ($type)($y)
|
|
) - 1];],
|
|
[break;])
|
|
negepsilon_bits=`expr $negepsilon_bits + 1`; y="$y * ($type)0.5"
|
|
done
|
|
echo "/* Properties of type \`$type': */"
|
|
echo "/* Largest n for which 1+2^(-n) is exactly represented is $epsilon_bits. */"
|
|
echo "/* Largest n for which 1-2^(-n) is exactly represented is $negepsilon_bits. */"
|
|
if test `expr $negepsilon_bits '<=' $epsilon_bits` = 1; then
|
|
echo "#error \"No exponent jump at 1.0 for type $type!\""
|
|
else
|
|
if test `expr $negepsilon_bits '>' $epsilon_bits + 1` = 1; then
|
|
echo "/* Base for type '$type' is 2^"`expr $negepsilon_bits - $epsilon_bits`
|
|
fi
|
|
echo "#define "`echo $type | sed -e 's, ,_,g'`"_mant_bits "`expr $epsilon_bits + 1`
|
|
fi
|
|
x="($type)1.0"
|
|
i=$epsilon_bits
|
|
while test $i != 0; do
|
|
x="$x * ($type)0.5"
|
|
i=`expr $i - 1`
|
|
done
|
|
x="($type)($x)"
|
|
y1="($type)(($type)1.0 + ($type)5.0*$x)"
|
|
y2="($type)(($type)1.0 + ($type)6.0*$x)"
|
|
ys1="($type)(($type)1.0 + ($type)5.4*$x)"
|
|
ys2="($type)(($type)1.0 + ($type)5.6*$x)"
|
|
z1="($type)(($type)-1.0 + ($type)(-5.0)*$x)"
|
|
z2="($type)(($type)-1.0 + ($type)(-6.0)*$x)"
|
|
zs1="($type)(($type)-1.0 + ($type)(-5.4)*$x)"
|
|
zs2="($type)(($type)-1.0 + ($type)(-5.6)*$x)"
|
|
rounds=
|
|
if test -z "$rounds"; then
|
|
AC_TRY_COMPILE([],
|
|
[typedef int verify[2*(
|
|
$ys1 == $y1 && $ys2 == $y2 && $zs1 == $z1 && $zs2 == $z2
|
|
) - 1];],
|
|
[rounds=rounds_to_nearest])
|
|
fi
|
|
if test -z "$rounds"; then
|
|
AC_TRY_COMPILE([],
|
|
[typedef int verify[2*(
|
|
$ys1 == $y1 && $ys2 == $y1 && $zs1 == $z1 && $zs2 == $z1
|
|
) - 1];],
|
|
[rounds=rounds_to_zero])
|
|
fi
|
|
if test -z "$rounds"; then
|
|
AC_TRY_COMPILE([],
|
|
[typedef int verify[2*(
|
|
$ys1 == $y2 && $ys2 == $y2 && $zs1 == $z1 && $zs2 == $z1
|
|
) - 1];],
|
|
[rounds=rounds_to_infinity])
|
|
fi
|
|
if test -z "$rounds"; then
|
|
AC_TRY_COMPILE([],
|
|
[typedef int verify[2*(
|
|
$ys1 == $y1 && $ys2 == $y1 && $zs1 == $z2 && $zs2 == $z2
|
|
) - 1];],
|
|
[rounds=rounds_to_minus_infinity])
|
|
fi
|
|
if test -n "$rounds"; then
|
|
echo "#define "`echo $type | sed -e 's, ,_,g'`"_rounds $rounds"
|
|
else
|
|
echo "#error \"Unknown rounding mode for type $type!\""
|
|
fi
|
|
echo
|
|
fi
|
|
done
|
|
dnl Words-in-a-double endianness test. Note that, assuming IEEE 754 format,
|
|
dnl 2.5479915693083957 = { 0x40 0x04 0x62 0x49 0x67 0x65 0x4E 0x64 } ..bIgeNd
|
|
dnl 1.4396527506122064e164 = { 0x62 0x04 0x00 0x00 0x4E 0x65 0x67 0x49 } b...NegI
|
|
dnl 2.5495230282078065 = { 0x40 0x04 0x65 0x6C 0x54 0x54 0x69 0x4C } ..elTTiL
|
|
dnl 1.4139248369879473e214 = { 0x6C 0x65 0x00 0x00 0x4C 0x69 0x54 0x54 } le..LiTT
|
|
double_wordorder_bigendian_p=
|
|
AC_TRY_COMPILE([double a[9] = {
|
|
0, 2.5479915693083957, 0, 1.4396527506122064e164,
|
|
0, 2.5495230282078065, 0, 1.4139248369879473e214,
|
|
0 };], [], [
|
|
if grep LiTTle conftest.$ac_objext >/dev/null ; then
|
|
double_wordorder_bigendian_p=0
|
|
else
|
|
if grep bIgeN conftest.$ac_objext >/dev/null ; then
|
|
double_wordorder_bigendian_p=1
|
|
fi
|
|
fi])
|
|
if test -n "$double_wordorder_bigendian_p"; then
|
|
echo "#define double_wordorder_bigendian_p $double_wordorder_bigendian_p"
|
|
else
|
|
echo "/* Dazed and confused! Better not define anything. */"
|
|
fi
|
|
echo
|
|
} > "$cl_machine_file_h"
|
|
])
|