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| author | Paul Eggert <eggert@cs.ucla.edu> | 2013-10-07 14:37:19 -0700 |
|---|---|---|
| committer | Paul Eggert <eggert@cs.ucla.edu> | 2013-10-07 14:37:19 -0700 |
| commit | 595e113b15e2ce80b95d39d1851ce78f25ffa1f4 (patch) | |
| tree | 42c02de46a13e0af39fcc83de9d57c29e309f99e /m4/count-trailing-zeros.m4 | |
| parent | ddb317ba828f05eb48e98fda530443955485e75d (diff) | |
| download | emacs-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-trailing-zeros.m4')
| -rw-r--r-- | m4/count-trailing-zeros.m4 | 12 |
1 files changed, 12 insertions, 0 deletions
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]) +]) |