config/hwcaps.m4

   1 dnl
   2 dnl Check if the assembler used supports disabling generation of hardware
   3 dnl capabilities.  This is only supported by Solaris as at the moment.
   4 dnl
   5 dnl Defines:
   6 dnl  HWCAP_CFLAGS='-Wa,-nH' if possible.
   7 dnl
   8 AC_DEFUN([GCC_CHECK_ASSEMBLER_HWCAP], [
   9   test -z "$HWCAP_CFLAGS" && HWCAP_CFLAGS=''
  10   AC_REQUIRE([AC_CANONICAL_TARGET])
  11
  12   # Restrict the test to Solaris, other assemblers (e.g. AIX as) have -nH
  13   # with a different meaning.
  14   case ${target_os} in
  15     solaris2*)
  16       ac_save_CFLAGS="$CFLAGS"
  17       CFLAGS="$CFLAGS -Wa,-nH"
  18
  19       AC_MSG_CHECKING([for as that supports -Wa,-nH])
  20       AC_TRY_COMPILE([], [return 0;], [ac_hwcap_flags=yes],[ac_hwcap_flags=no])
  21       if test "$ac_hwcap_flags" = "yes"; then
  22         HWCAP_CFLAGS="-Wa,-nH $HWCAP_CFLAGS"
  23       fi
  24       AC_MSG_RESULT($ac_hwcap_flags)
  25
  26       CFLAGS="$ac_save_CFLAGS"
  27       ;;
  28   esac
  29
  30   AC_SUBST(HWCAP_CFLAGS)
  31 ])
  32
  33
  34 dnl
  35 dnl Check if the linker used supports linker maps to clear hardware
  36 dnl capabilities.  This is only supported on Solaris at the moment.
  37 dnl
  38 dnl Defines:
  39 dnl  HWCAP_LDFLAGS=-mclear-hwcap if possible
  40 dnl  LD (as a side effect of testing)
  41 dnl
  42 AC_DEFUN([GCC_CHECK_LINKER_HWCAP], [
  43   test -z "$HWCAP_LDFLAGS" && HWCAP_LDFLAGS=''
  44   AC_REQUIRE([AC_PROG_LD])
  45
  46   ac_save_LDFLAGS="$LDFLAGS"
  47   LDFLAGS="$LFLAGS -mclear-hwcap"
  48
  49   AC_MSG_CHECKING([for -mclear-hwcap])
  50   AC_TRY_LINK([], [return 0;], [ac_hwcap_ldflags=yes],[ac_hwcap_ldflags=no])
  51   if test "$ac_hwcap_ldflags" = "yes"; then
  52     HWCAP_LDFLAGS="-mclear-hwcap $HWCAP_LDFLAGS"
  53   fi
  54   AC_MSG_RESULT($ac_hwcap_ldflags)
  55
  56   LDFLAGS="$ac_save_LDFLAGS"
  57
  58   AC_SUBST(HWCAP_LDFLAGS)
  59
  60   AM_CONDITIONAL(HAVE_HWCAP, test $ac_hwcap_ldflags != no)
  61 ])