--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/config/dfp.m4	Sun Aug 21 07:53:12 2011 +0900
@@ -0,0 +1,56 @@
+dnl @synopsis GCC_AC_ENABLE_DECIMAL_FLOAT([target triplet])
+dnl
+dnl Enable C extension for decimal float if target supports it.
+dnl
+dnl @author Andreas Krebbel  <Andreas.Krebbel@de.ibm.com>
+
+AC_DEFUN([GCC_AC_ENABLE_DECIMAL_FLOAT],
+[
+AC_ARG_ENABLE(decimal-float,
+[  --enable-decimal-float={no,yes,bid,dpd}
+			enable decimal float extension to C.  Selecting 'bid'
+			or 'dpd' choses which decimal floating point format
+			to use],
+[
+  case $enable_decimal_float in
+    yes | no | bid | dpd) default_decimal_float=$enable_decimal_float ;;
+    *) AC_MSG_ERROR(['$enable_decimal_float' is an invalid value for --enable-decimal-float.
+Valid choices are 'yes', 'bid', 'dpd', and 'no'.]) ;;
+  esac
+],
+[
+  case $1 in
+    powerpc*-*-linux* | i?86*-*-linux* | x86_64*-*-linux* | s390*-*-linux* | \
+    i?86*-*-mingw* | x86_64*-*-mingw* | \
+    i?86*-*-cygwin*)
+      enable_decimal_float=yes
+      ;;
+    *)
+      AC_MSG_WARN([decimal float is not supported for this target, ignored])
+      enable_decimal_float=no
+      ;;
+  esac
+])
+
+# x86's use BID format instead of DPD
+case x$enable_decimal_float in
+  xyes)
+    case $1 in
+      i?86*-*-* | x86_64*-*-*)
+	enable_decimal_float=bid
+	;;
+      *)
+	enable_decimal_float=dpd
+	;;
+    esac
+    default_decimal_float=$enable_decimal_float
+    ;;
+  xno)
+    # ENABLE_DECIMAL_FLOAT is set to 0. But we have to have proper
+    # dependency on libdecnumber.
+    default_decimal_float=dpd
+    ;;
+esac
+AC_SUBST(enable_decimal_float)
+
+])