* fixed-value.h: New file.
	* fixed-value.c: New file.
	* Makefile.in (OBJS-common): Add fixed-value.o.
	(fixed-value.o): New rule.
	(GTFILES): Add fixed-value.h.
	* double-int.c (double_int_scmp): We should use unsigned HOST_WIDE_INT
	to compare a.low and b.low.
	* gengtype.c (main): Handle FIXED_VALUE_TYPE type as scalar typedef.

From-SVN: r127260