From 595e113b15e2ce80b95d39d1851ce78f25ffa1f4 Mon Sep 17 00:00:00 2001 From: Paul Eggert Date: Mon, 7 Oct 2013 14:37:19 -0700 Subject: 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 , . (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 --- m4/count-trailing-zeros.m4 | 12 ++++++++++++ 1 file changed, 12 insertions(+) create mode 100644 m4/count-trailing-zeros.m4 (limited to 'm4/count-trailing-zeros.m4') diff --git a/m4/count-trailing-zeros.m4 b/m4/count-trailing-zeros.m4 new file mode 100644 index 00000000000..b4a13c14397 --- /dev/null +++ b/m4/count-trailing-zeros.m4 @@ -0,0 +1,12 @@ +# count-trailing-zeros.m4 +dnl Copyright (C) 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_TRAILING_ZEROS], +[ + dnl We don't need (and can't compile) count_trailing_zeros_ll + dnl unless the type 'unsigned long long int' exists. + AC_REQUIRE([AC_TYPE_UNSIGNED_LONG_LONG_INT]) +]) -- cgit v1.2.3