faster popcount, tested

Makefile.in

@@ -1,7 +1,7 @@
-# Makefile.in generated by automake 1.16.1 from Makefile.am.
+# Makefile.in generated by automake 1.15.1 from Makefile.am.
 # @configure_input@
 
-# Copyright (C) 1994-2018 Free Software Foundation, Inc.
+# Copyright (C) 1994-2017 Free Software Foundation, Inc.
 
 # This Makefile.in is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
@@ -137,7 +137,7 @@ am__recursive_targets = \
   $(RECURSIVE_CLEAN_TARGETS) \
   $(am__extra_recursive_targets)
 AM_RECURSIVE_TARGETS = $(am__recursive_targets:-recursive=) TAGS CTAGS \
-	cscope distdir distdir-am dist dist-all distcheck
+	cscope distdir dist dist-all distcheck
 am__tagged_files = $(HEADERS) $(SOURCES) $(TAGS_FILES) $(LISP)
 # Read a list of newline-separated strings from the standard input,
 # and print each of them once, without duplicates.  Input order is
@@ -358,8 +358,8 @@ Makefile: $(srcdir)/Makefile.in $(top_builddir)/config.status
 	    echo ' $(SHELL) ./config.status'; \
 	    $(SHELL) ./config.status;; \
 	  *) \
-	    echo ' cd $(top_builddir) && $(SHELL) ./config.status $@ $(am__maybe_remake_depfiles)'; \
-	    cd $(top_builddir) && $(SHELL) ./config.status $@ $(am__maybe_remake_depfiles);; \
+	    echo ' cd $(top_builddir) && $(SHELL) ./config.status $@ $(am__depfiles_maybe)'; \
+	    cd $(top_builddir) && $(SHELL) ./config.status $@ $(am__depfiles_maybe);; \
 	esac;
 
 $(top_builddir)/config.status: $(top_srcdir)/configure $(CONFIG_STATUS_DEPENDENCIES)
@@ -486,10 +486,7 @@ distclean-tags:
 	-rm -f TAGS ID GTAGS GRTAGS GSYMS GPATH tags
 	-rm -f cscope.out cscope.in.out cscope.po.out cscope.files
 
-distdir: $(BUILT_SOURCES)
-	$(MAKE) $(AM_MAKEFLAGS) distdir-am
-
-distdir-am: $(DISTFILES)
+distdir: $(DISTFILES)
 	$(am__remove_distdir)
 	test -d "$(distdir)" || mkdir "$(distdir)"
 	@srcdirstrip=`echo "$(srcdir)" | sed 's/[].[^$$\\*]/\\\\&/g'`; \