summaryrefslogtreecommitdiff
path: root/m4/count-one-bits.m4
diff options
context:
space:
mode:
authorPaul Eggert <eggert@cs.ucla.edu>2013-10-07 14:37:19 -0700
committerPaul Eggert <eggert@cs.ucla.edu>2013-10-07 14:37:19 -0700
commit595e113b15e2ce80b95d39d1851ce78f25ffa1f4 (patch)
tree42c02de46a13e0af39fcc83de9d57c29e309f99e /m4/count-one-bits.m4
parentddb317ba828f05eb48e98fda530443955485e75d (diff)
downloademacs-595e113b15e2ce80b95d39d1851ce78f25ffa1f4.tar.gz
Improve support for popcount and counting trailing zeros.
Do this by using the Gnulib modules for this. This should generate faster code on non-GCC, non-MSC platforms, and make the code a bit more portable, at least in theory. * admin/merge-gnulib (GNULIB_MODULES): Add count-one-bits and count-trailing-zeros. * lib/count-one-bits.c, lib/count-one-bits.h: * lib/count-trailing-zeros.c, lib/count-trailing-zeros.h: * m4/count-one-bits.m4, m4/count-trailing-zeros.m4: New files, copied from gnulib. * lib/gnulib.mk, m4/gnulib-comp.m4: Regenerate. * nt/gnulib.mk: Merge changes from lib/gnulib.mk. * src/data.c: Include <count-one-bits.h>, <count-trailing-zeros.h>. (USE_MSC_POPCOUNT, POPCOUNT_STATIC_INLINE) (NEED_GENERIC_POPCOUNT, popcount_size_t_generic) (popcount_size_t_msc, popcount_size_t_gcc): Remove; now done by Gnulib. (popcount_size_t): Now a macro that defers to Gnulib. (count_trailing_zero_bits): Return int, for consistency with Gnulib and because Emacs prefers signed to unsigned int. Don't assume that size_t is either unsigned int or unsigned long or unsigned long long. (size_t_to_host_endian): Do not assume that size_t is either exactly 32 or exactly 64 bits wide. * src/lisp.h (BITS_PER_SIZE_T): Define consistently with BITS_PER_LONG etc., so that it's now an enum constant, not a macro. No need to assume that it's either 32 or 64. Fixes: debbugs:15550
Diffstat (limited to 'm4/count-one-bits.m4')
-rw-r--r--m4/count-one-bits.m412
1 files changed, 12 insertions, 0 deletions
diff --git a/m4/count-one-bits.m4 b/m4/count-one-bits.m4
new file mode 100644
index 00000000000..07289641d4a
--- /dev/null
+++ b/m4/count-one-bits.m4
@@ -0,0 +1,12 @@
+# count-one-bits.m4 serial 3
+dnl Copyright (C) 2007, 2009-2013 Free Software Foundation, Inc.
+dnl This file is free software; the Free Software Foundation
+dnl gives unlimited permission to copy and/or distribute it,
+dnl with or without modifications, as long as this notice is preserved.
+
+AC_DEFUN([gl_COUNT_ONE_BITS],
+[
+ dnl We don't need (and can't compile) count_one_bits_ll
+ dnl unless the type 'unsigned long long int' exists.
+ AC_REQUIRE([AC_TYPE_UNSIGNED_LONG_LONG_INT])
+])