lihao/jemalloc
1
0
Fork 0
mirror of https://github.com/jemalloc/jemalloc.git synced 2026-07-24 13:53:11 +00:00
Code Issues Packages Projects Releases Wiki Activity

Use __sync_add_and_fetch and __sync_sub_and_fetch when they are available

Browse Source 
These functions may be available as inlines or as libgcc functions. In the
former case, a __GCC_HAVE_SYNC_COMPARE_AND_SWAP_n macro is defined. But we
still want to use these functions in the latter case, when we don't have
our own implementation.
This commit is contained in:
Mike Hommey
2012-03-26 17:03:41 +02:00
committed by Jason Evans
parent 1e6138c88c
commit c1e567bda0
3 changed files with 65 additions and 3 deletions
Download Patch File Download Diff File Expand all files Collapse all files

34
configure.ac
View File

@@ -886,6 +886,40 @@ if test "x${je_cv_osatomic}" = "xyes" ; then
AC_DEFINE([JEMALLOC_OSATOMIC], [ ])
fi
dnl ============================================================================
dnl Check whether __sync_{add,sub}_and_fetch() are available despite
dnl __GCC_HAVE_SYNC_COMPARE_AND_SWAP_n macros being undefined.
AC_DEFUN([JE_SYNC_COMPARE_AND_SWAP_CHECK],[
AC_CACHE_CHECK([whether to force $1-bit __sync_{add,sub}_and_fetch()],
[je_cv_sync_compare_and_swap_$2],
[AC_COMPILE_IFELSE([AC_LANG_PROGRAM([
#include <stdint.h>
],
[
#ifndef __GCC_HAVE_SYNC_COMPARE_AND_SWAP_$2
{
uint$1_t x$1 = 0;
__sync_add_and_fetch(&x$1, 42);
__sync_sub_and_fetch(&x$1, 1);
}
#else
#error __GCC_HAVE_SYNC_COMPARE_AND_SWAP_$2 is defined, no need to force
#endif
])],
[je_cv_sync_compare_and_swap_$2=yes],
[je_cv_sync_compare_and_swap_$2=no])])
if test "x${je_cv_sync_compare_and_swap_$2}" = "xyes" ; then
AC_DEFINE([JE_FORCE_SYNC_COMPARE_AND_SWAP_$2], [ ])
fi
])
if test "x${je_cv_osatomic}" != "xyes" ; then
JE_SYNC_COMPARE_AND_SWAP_CHECK(32, 4)
JE_SYNC_COMPARE_AND_SWAP_CHECK(64, 8)
fi
dnl ============================================================================
dnl Check for spinlock(3) operations as provided on Darwin.