dnl  MPFR specific autoconf macros

dnl  Copyright 2000, 2002, 2003 Free Software Foundation.
dnl  Contributed by the Spaces project, INRIA Lorraine.
dnl  
dnl  This file is part of the MPFR Library.
dnl  
dnl  The MPFR Library is free software; you can redistribute it and/or modify
dnl  it under the terms of the GNU Lesser General Public License as published
dnl  by the Free Software Foundation; either version 2.1 of the License, or (at
dnl  your option) any later version.
dnl  
dnl  The MPFR Library is distributed in the hope that it will be useful, but
dnl  WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
dnl  or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
dnl  License for more details.
dnl  
dnl  You should have received a copy of the GNU Lesser General Public License
dnl  along with the MPFR Library; see the file COPYING.LIB.  If not, write to
dnl  the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
dnl  MA 02111-1307, USA.

dnl  autoconf 2.50 is necessary because of the use of AH_VERBATIM,
dnl  but it would be better to make the config file compatible with
dnl  both autoconf 2.13 and autoconf 2.50.
dnl  The following line allows the autoconf wrapper (when installed)
dnl  to work as expected.
AC_PREREQ(2.50)

AC_DEFUN([AC_MY_LIBS],
[
if ` test "$1" `
then  
  AC_MSG_CHECKING($2 library)
	if  test -r "$1/lib$2.a"
	then
	  LIBS="$LIBS $1/lib$2.a"
	else
	if  test -r "$1/lib$2.so"
	then
	  LIBS="$LIBS $1/lib$2.so"
	else
	   AC_MSG_ERROR($1/lib$2.a/so not found)
	fi
	fi
  AC_MSG_RESULT(yes)
else
  AC_CHECK_LIB($2, main, , AC_MSG_ERROR($2 not found))
fi
]
)

dnl FIXME: Buggy?
AC_DEFUN([AC_MY_HEADERS], 
[
if  test "$1" 
then  
  AC_CHECK_HEADER($1/$2, INCLUDES="$INCLUDES -I$1",AC_MSG_ERROR($2 not found in $1)) 
else
  AC_CHECK_HEADER($2,, 	  AC_MSG_ERROR($2 not found))
fi
])

AC_DEFUN([AC_CHECK_OS], 
[
AC_CACHE_CHECK([OS type], mpfr_cv_os_type, [
  mpfr_cv_os_type=`uname -s`
])
OS_TYPE=$mpfr_cv_os_type
])

AC_DEFUN([AC_CHECK_MACHTYPE],
[
AC_CACHE_CHECK([Mach type], mpfr_cv_mach_type, [
  mpfr_cv_mach_type=`uname -m`
])
MACHTYPE=$mpfr_cv_mach_type
])

dnl ------------------------------------------------------------

AC_DEFUN([MPFR_CONFIGS],
[
AC_REQUIRE([AC_OBJEXT])
AC_REQUIRE([MPFR_CHECK_LIBM])
AC_REQUIRE([AC_HEADER_TIME])

# CPU-dependent objects for the test programs
case $host in
  X86_PATTERN)
    AC_SUBST(TESTS_ASM_OBJECTS, x86.$OBJEXT)
    AC_DEFINE(MPFR_HAVE_TESTS_x86, 1,
              [Define to 1 if mpfr x86/amd64 test routines are available.])
    ;;
  amd64-*-*)
    AC_SUBST(TESTS_ASM_OBJECTS, amd64.$OBJEXT)
    AC_DEFINE(MPFR_HAVE_TESTS_x86, 1)
    ;;
esac

dnl Check for sizeof size_t
dnl AC_CHECK_SIZEOF
dnl AC_TYPE_SIZE_T

dnl
AC_CHECK_FUNCS([memset])
AC_CHECK_FUNCS([strtol])
AC_CHECK_HEADER([limits.h],, AC_MSG_ERROR([limits.h not found]))
AC_CHECK_HEADER([float.h],,  AC_MSG_ERROR([float.h not found]))

dnl Check for stdargs
AC_CHECK_HEADER([stdarg.h],[AC_DEFINE([HAVE_STDARG])],
	[AC_CHECK_HEADER([varargs.h],, 
	AC_MSG_ERROR([stdarg.h or varargs.h not found]))])

AC_CHECK_HEADERS(sys/time.h)

# Reasons for testing:
#   gettimeofday - not in mingw
#
AC_CHECK_FUNCS(gettimeofday)
AC_REPLACE_FUNCS(strcasecmp strncasecmp)

dnl Check for IEEE-754 switches on Alpha
case $host in
alpha*-*-*)
  saved_CFLAGS="$CFLAGS"
  AC_CACHE_CHECK([for IEEE-754 switches], mpfr_cv_ieee_switches, [
  if test -n "$GCC"; then
    mpfr_cv_ieee_switches="-mfp-rounding-mode=d -mieee-with-inexact"
  else
    mpfr_cv_ieee_switches="-fprm d -ieee_with_inexact"
  fi
  CFLAGS="$CFLAGS $mpfr_cv_ieee_switches"
  AC_TRY_COMPILE(,,, mpfr_cv_ieee_switches="none")
  ])
  if test "$mpfr_cv_ieee_switches" = "none"; then
    CFLAGS="$saved_CFLAGS"
  else
    CFLAGS="$saved_CFLAGS $mpfr_cv_ieee_switches"
  fi
esac

# Reasons for testing:
#   sys/fpu.h - MIPS specific
#
AC_CHECK_HEADERS(sys/fpu.h)

dnl Check for fesetround
AC_CACHE_CHECK([for fesetround], mpfr_cv_have_fesetround, [
saved_LIBS="$LIBS"
LIBS="$LIBS $MPFR_LIBM"
AC_TRY_LINK([#include <fenv.h>], [fesetround(FE_TONEAREST);],
  mpfr_cv_have_fesetround=yes, mpfr_cv_have_fesetround=no)
LIBS="$saved_LIBS"
])
if test "$mpfr_cv_have_fesetround" = "yes"; then
  AC_DEFINE(MPFR_HAVE_FESETROUND,1,[Define if you have the `fesetround' function via the <fenv.h> header file.])
fi

dnl Check whether 0/0, 1/0, -1/0, sqrt(-1) are valid expressions
AC_CACHE_CHECK([for valid NaN], mpfr_cv_valid_nan, [
AC_TRY_RUN([
#include <math.h>
int main()
{
  double x = (0.0/0.0) + sqrt(-1.0);
  return x == 1.0/0.0;
}
], mpfr_cv_valid_nan=yes, mpfr_cv_valid_nan=no, mpfr_cv_valid_nan=no)
])
if test "$mpfr_cv_valid_nan" = "yes"; then
   AC_DEFINE(HAVE_INFS,1,[Define if 0/0, 1/0, -1/0 and sqrt(-1) work to generate NaN/infinities.])
fi

dnl Check for gcc float-conversion bug; if need be, -ffloat-store is used to
dnl force the conversion to the destination type when a value is stored to
dnl a variable (see ISO C99 standard 5.1.2.3#13, 6.3.1.5#2, 6.3.1.8#2). This
dnl is important concerning the exponent range. Note that this doesn't solve
dnl the double-rounding problem (x86 processors still have to be set to the
dnl IEEE-754 compatible rounding mode).
if test -n "$GCC"; then
  AC_CACHE_CHECK([for gcc float-conversion bug], mpfr_cv_gcc_floatconv_bug, [
  saved_LIBS="$LIBS"
  LIBS="$LIBS $MPFR_LIBM"
  AC_TRY_RUN([
#include <float.h>
#ifdef MPFR_HAVE_FESETROUND
#include <fenv.h>
#endif
int main()
{
  double x = 0.5;
  int i;
  for (i = 1; i <= 11; i++)
    x *= x;
  if (x != 0)
    return 1;
#ifdef MPFR_HAVE_FESETROUND
  /* Useful test for the G4 PowerPC */
  fesetround(FE_TOWARDZERO);
  x = DBL_MAX;
  x *= 2.0;
  if (x != DBL_MAX)
    return 1;
#endif
  return 0;
}
  ], [mpfr_cv_gcc_floatconv_bug="no"],
     [mpfr_cv_gcc_floatconv_bug="yes, use -ffloat-store"],
     [mpfr_cv_gcc_floatconv_bug="cannot test, use -ffloat-store"])
  LIBS="$saved_LIBS"
  ])
  if test "$mpfr_cv_gcc_floatconv_bug" != "no"; then
    CFLAGS="$CFLAGS -ffloat-store"
  fi
fi

dnl Check if denormalized numbers are supported
AC_CACHE_CHECK([for denormalized numbers], mpfr_cv_have_denorms, [
AC_TRY_RUN([
#include <math.h>
#include <stdio.h>
int main()
{
  double x = 2.22507385850720138309e-308;
  fprintf (stderr, "%e\n", x / 2.0);
  return 2.0 * (x / 2.0) != x;
}
], mpfr_cv_have_denorms=yes, mpfr_cv_have_denorms=no, mpfr_cv_have_denorms=no)
])
if test "$mpfr_cv_have_denorms" = "yes"; then
  AC_DEFINE(HAVE_DENORMS,1,[Define if denormalized floats work.])
fi

dnl Check if HUGE_VAL is supported without the need of a specific library
AC_CACHE_CHECK([for HUGE_VAL], mpfr_cv_have_huge_val, [
AC_TRY_LINK([#include <math.h>], [HUGE_VAL;],
  mpfr_cv_have_huge_val=yes, mpfr_cv_have_huge_val=no)
])
if test "$mpfr_cv_have_huge_val" = "yes"; then
  AC_DEFINE(HAVE_HUGE_VAL,1,[Define if HUGE_VAL can be used without the need of a specific library.])
fi

MPFR_C_LONG_DOUBLE_FORMAT
])


dnl  MPFR_C_LONG_DOUBLE_FORMAT
dnl  -------------------------
dnl  Determine the format of a long double.
dnl
dnl  The object file is grepped, so as to work when cross compiling.  A
dnl  start and end sequence is included to avoid false matches, and
dnl  allowance is made for the desired data crossing an "od -b" line
dnl  boundary.  The test number is a small integer so it should appear
dnl  exactly, no rounding or truncation etc.
dnl
dnl  "od -b" is supported even by Unix V7, and the awk script used doesn't
dnl  have functions or anything, so even an "old" awk should suffice.
dnl
dnl  The 10-byte IEEE extended format is generally padded to either 12 or 16
dnl  bytes for alignment purposes.  The SVR4 i386 ABI is 12 bytes, or i386
dnl  gcc -m128bit-long-double selects 16 bytes.  IA-64 is 16 bytes in LP64
dnl  mode, or 12 bytes in ILP32 mode.  The first 10 bytes is the relevant
dnl  part in all cases (big and little endian).
dnl
dnl  Enhancements:
dnl
dnl  Could match more formats, but no need to worry until there's code
dnl  wanting to use them.
dnl
dnl  Don't want to duplicate the double matching from GMP_C_DOUBLE_FORMAT,
dnl  perhaps we should merge with that macro, to match data formats
dnl  irrespective of the C type in question.  Or perhaps just let the code
dnl  use DOUBLE macros when sizeof(double)==sizeof(long double).

AC_DEFUN([MPFR_C_LONG_DOUBLE_FORMAT],
[AC_REQUIRE([AC_PROG_CC])
AC_REQUIRE([AC_PROG_AWK])
AC_REQUIRE([AC_OBJEXT])
AC_CHECK_TYPES([long double])
AC_CACHE_CHECK([format of `long double' floating point],
                mpfr_cv_c_long_double_format,
[mpfr_cv_c_long_double_format=unknown
if test "$ac_cv_type_long_double" != yes; then
  mpfr_cv_c_long_double_format="not available"
else
  cat >conftest.c <<\EOF
[
/* "before" is 16 bytes to ensure there's no padding between it and "x".
   We're not expecting any "long double" bigger than 16 bytes or with
   alignment requirements stricter than 16 bytes.  */
struct {
  char         before[16];
  long double  x;
  char         after[8];
} foo = {
  { '\0', '\0', '\0', '\0', '\0', '\0', '\0', '\0',
    '\001', '\043', '\105', '\147', '\211', '\253', '\315', '\357' },
  -123456789.0,
  { '\376', '\334', '\272', '\230', '\166', '\124', '\062', '\020' }
};
]
EOF
  mpfr_compile="$CC $CFLAGS $CPPFLAGS -c conftest.c >&AC_FD_CC 2>&1"
  if AC_TRY_EVAL(mpfr_compile); then
    cat >conftest.awk <<\EOF
[
BEGIN {
  found = 0
}

# got[] holds a sliding window of bytes read the input.  got[0] is the most
# recent byte read, and got[31] the oldest byte read, so when looking to
# match some data the indices are "reversed".
#
{
  for (f = 2; f <= NF; f++)
    {
      # new byte, shift others up
      for (i = 31; i >= 0; i--)
        got[i+1] = got[i];
      got[0] = $f;

      # end sequence
      if (got[7] != "376") continue
      if (got[6] != "334") continue
      if (got[5] != "272") continue
      if (got[4] != "230") continue
      if (got[3] != "166") continue
      if (got[2] != "124") continue
      if (got[1] != "062") continue
      if (got[0] != "020") continue

      # start sequence, with 12-byte body
      if (got[27] == "001" && \
          got[26] == "043" && \
          got[25] == "105" && \
          got[24] == "147" && \
          got[23] == "211" && \
          got[22] == "253" && \
          got[21] == "315" && \
          got[20] == "357")
        {
          saw = " (" got[19] \
                 " " got[18] \
                 " " got[17] \
                 " " got[16] \
                 " " got[15] \
                 " " got[14] \
                 " " got[13] \
                 " " got[12] \
                 " " got[11] \
                 " " got[10] \
                 " " got[9]  \
                 " " got[8] ")"

          if (got[19] == "000" && \
              got[18] == "000" && \
              got[17] == "000" && \
              got[16] == "000" && \
              got[15] == "240" && \
              got[14] == "242" && \
              got[13] == "171" && \
              got[12] == "353" && \
              got[11] == "031" && \
              got[10] == "300")
            {
              print "IEEE extended, little endian"
              found = 1
              exit
            }
        }

      # start sequence, with 16-byte body
      if (got[31] == "001" && \
          got[30] == "043" && \
          got[29] == "105" && \
          got[28] == "147" && \
          got[27] == "211" && \
          got[26] == "253" && \
          got[25] == "315" && \
          got[24] == "357")
        {
          saw = " (" got[23] \
                 " " got[22] \
                 " " got[21] \
                 " " got[20] \
                 " " got[19] \
                 " " got[18] \
                 " " got[17] \
                 " " got[16] \
                 " " got[15] \
                 " " got[14] \
                 " " got[13] \
                 " " got[12] \
                 " " got[11] \
                 " " got[10] \
                 " " got[9]  \
                 " " got[8] ")"

          if (got[23] == "000" && \
              got[22] == "000" && \
              got[21] == "000" && \
              got[20] == "000" && \
              got[19] == "240" && \
              got[18] == "242" && \
              got[17] == "171" && \
              got[16] == "353" && \
              got[15] == "031" && \
              got[14] == "300")
            {
              print "IEEE extended, little endian"
              found = 1
              exit
            }

          if (got[23] == "300" && \
	      got[22] == "031" && \
	      got[21] == "326" && \
	      got[20] == "363" && \
	      got[19] == "105" && \
	      got[18] == "100" && \
	      got[17] == "000" && \
	      got[16] == "000" && \
	      got[15] == "000" && \
	      got[14] == "000" && \
	      got[13] == "000" && \
	      got[12] == "000" && \
	      got[11] == "000" && \
	      got[10] == "000" && \
	      got[9]  == "000" && \
	      got[8]  == "000")
            {
              print "IEEE quad, big endian"
              found = 1
              exit
            }
        }
    }
}

END {
  if (! found)
    print "unknown", saw
}
]
EOF
    mpfr_cv_c_long_double_format=`od -b conftest.$OBJEXT | $AWK -f conftest.awk`
    case $mpfr_cv_c_long_double_format in
    unknown*)
      echo "cannot match anything, conftest.$OBJEXT contains" >&AC_FD_CC
      od -b conftest.$OBJEXT >&AC_FD_CC
      ;;
    esac
  else
    AC_MSG_WARN([oops, cannot compile test program])
  fi
fi
rm -f conftest*
])

AH_VERBATIM([HAVE_LDOUBLE],
[/* Define one of the following to 1 for the format of a `long double'.
   If your format is not among these choices, or you don't know what it is,
   then leave all undefined.
   IEEE_EXT is the 10-byte IEEE extended precision format.
   IEEE_QUAD is the 16-byte IEEE quadruple precision format.
   LITTLE or BIG is the endianness.  */
#undef HAVE_LDOUBLE_IEEE_EXT_LITTLE
#undef HAVE_LDOUBLE_IEEE_QUAD_BIG])

case $mpfr_cv_c_long_double_format in
  "IEEE extended, little endian")
    AC_DEFINE(HAVE_LDOUBLE_IEEE_EXT_LITTLE, 1)
    ;;
  "IEEE quad, big endian")
    AC_DEFINE(HAVE_LDOUBLE_IEEE_QUAD_BIG, 1)
    ;;
  unknown* | "not available")
    ;;
  *) 
    AC_MSG_WARN([oops, unrecognised float format: $mpfr_cv_c_long_double_format])
    ;;
esac
])


dnl  MPFR_CHECK_LIBM
dnl  ---------------
dnl  Determine a math library -lm to use.

AC_DEFUN([MPFR_CHECK_LIBM],
[AC_REQUIRE([AC_CANONICAL_HOST])
AC_SUBST(MPFR_LIBM,'')
case $host in
  *-*-beos* | *-*-cygwin* | *-*-pw32*)
    # According to libtool AC CHECK LIBM, these systems don't have libm
    ;;
  *-*-hpux*)
    # -lM means something subtly different to -lm, SVID style error handling
    # or something.  FIXME: Why exactly do we want this?
    AC_CHECK_LIB(M, main, MPFR_LIBM="-lM")
    ;;
  *-*-solaris*)
    # On Solaris the math functions new in C99 are in -lm9x.
    # FIXME: Do we need -lm9x as well as -lm, or just instead of?
    AC_CHECK_LIB(m9x, main, MPFR_LIBM="-lm9x")
    AC_CHECK_LIB(m,   main, MPFR_LIBM="$MPFR_LIBM -lm")
    ;;
  *-ncr-sysv4.3*)
    # FIXME: What does -lmw mean?  Libtool AC CHECK LIBM does it this way.
    AC_CHECK_LIB(mw, _mwvalidcheckl, MPFR_LIBM="-lmw")
    AC_CHECK_LIB(m, main, MPFR_LIBM="$MPFR_LIBM -lm")
    ;;
  *)
    AC_CHECK_LIB(m, main, MPFR_LIBM="-lm")
    ;;
esac
])