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ChangeSet@stripped, 2008-01-08 12:06:54-02:00, davi@stripped +3 -0
Bug#33728 Atomic builtins
Use compiler provided atomic builtins as a 'backend' for
MySQL's atomic primitives. The builtins are available on
a handful of platforms and compilers.
configure.in@stripped, 2008-01-08 12:06:52-02:00, davi@stripped +23 -0
Check if the compiler provides atomic builtins and
that __sync_lock_test_and_set stores the correct value.
include/atomic/builtins.h@stripped, 2008-01-08 12:06:52-02:00, davi@stripped +33 -0
Implement the atomic ADD, SWAP, CAS, STORE (or operation
optimized away) and LOAD primitives using atomic builtins
provided by the compiler.
include/atomic/builtins.h@stripped, 2008-01-08 12:06:52-02:00, davi@stripped +0 -0
include/atomic/nolock.h@stripped, 2008-01-08 12:06:52-02:00, davi@stripped +4 -2
Use the atomic builtins if available.
diff -Nrup a/configure.in b/configure.in
--- a/configure.in 2007-12-14 15:03:30 -02:00
+++ b/configure.in 2008-01-08 12:06:52 -02:00
@@ -1688,6 +1688,29 @@ case "$with_atomic_ops" in
*) AC_MSG_ERROR(["$with_atomic_ops" is not a valid value for --with-atomic-ops]) ;;
esac
+AC_CACHE_CHECK([whether the compiler provides atomic builtins],
+ [mysql_cv_atomic_builtins], [AC_TRY_RUN([
+ int main()
+ {
+ int foo= -10; int bar= 10;
+ __sync_fetch_and_add(&foo, bar);
+ if (foo)
+ return -1;
+ bar= __sync_lock_test_and_set(&foo, bar);
+ if (bar || foo != 10)
+ return -1;
+ bar= __sync_val_compare_and_swap(&bar, foo, 15);
+ if (bar)
+ return -1;
+ return 0;
+ }
+], [mysql_cv_atomic_builtins=yes], [mysql_cv_atomic_builtins=no])])
+
+if test "x$mysql_cv_atomic_builtins" = xyes; then
+ AC_DEFINE(HAVE_ATOMIC_BUILTINS, 1,
+ [Define to 1 if compiler provides atomic builtins.])
+fi
+
# Force static compilation to avoid linking problems/get more speed
AC_ARG_WITH(mysqld-ldflags,
[ --with-mysqld-ldflags Extra linking arguments for mysqld],
diff -Nrup a/include/atomic/builtins.h b/include/atomic/builtins.h
--- /dev/null Wed Dec 31 16:00:00 196900
+++ b/include/atomic/builtins.h 2008-01-08 12:06:52 -02:00
@@ -0,0 +1,33 @@
+/* Copyright (C) 2008 MySQL AB
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; version 2 of the License.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */
+
+#define make_atomic_add_body(S) \
+ v= __sync_fetch_and_add(a, v);
+#define make_atomic_swap_body(S) \
+ v= __sync_lock_test_and_set(a, v);
+#define make_atomic_cas_body(S) \
+ int ## S sav; \
+ sav= __sync_val_compare_and_swap(a, *cmp, set); \
+ if (!(ret= (sav == *cmp))) *cmp= sav;
+
+#ifdef MY_ATOMIC_MODE_DUMMY
+#define make_atomic_load_body(S) ret= *a
+#define make_atomic_store_body(S) *a= v
+#else
+#define make_atomic_load_body(S) \
+ ret= __sync_fetch_and_or(a, 0);
+#define make_atomic_store_body(S) \
+ (void) __sync_lock_test_and_set(a, v);
+#endif
diff -Nrup a/include/atomic/nolock.h b/include/atomic/nolock.h
--- a/include/atomic/nolock.h 2006-12-23 17:33:28 -02:00
+++ b/include/atomic/nolock.h 2008-01-08 12:06:52 -02:00
@@ -13,7 +13,7 @@
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */
-#if defined(__i386__) || defined(_M_IX86)
+#if defined(__i386__) || defined(_M_IX86) || defined(HAVE_ATOMIC_BUILTINS)
#ifdef MY_ATOMIC_MODE_DUMMY
# define LOCK ""
@@ -21,7 +21,9 @@
# define LOCK "lock"
#endif
-#ifdef __GNUC__
+#ifdef HAVE_ATOMIC_BUILTINS
+#include "builtins.h"
+#elif __GNUC__
#include "x86-gcc.h"
#elif defined(_MSC_VER)
#include "x86-msvc.h"
