From 2c770d676c4089d7f57abb9ed885d3e458ba6b39 Mon Sep 17 00:00:00 2001 From: shyouhei Date: Mon, 25 Oct 2010 07:46:53 +0000 Subject: [PATCH] * signal.c (rb_atomic_t): GCC (of at least recent versions) has ubiquitos support for atomic operations. On that compiler a C program can isse a memory barrier using these dedicated instructions. According to the GCC manual they cargo culted this feature form the Itanium ABI so chances are that other compilers could also support this feature. But so far GCC is the only compiler that I know to have it. Also note that this works on non-Itanium machines. git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@29589 b2dd03c8-39d4-4d8f-98ff-823fe69b080e --- ChangeLog | 11 +++++++++++ signal.c | 11 +++++++++++ 2 files changed, 22 insertions(+) diff --git a/ChangeLog b/ChangeLog index a0cf409a37..bc193350e4 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,14 @@ +Mon Oct 25 16:38:07 2010 URABE Shyouhei + + * signal.c (rb_atomic_t): GCC (of at least recent versions) + has ubiquitos support for atomic operations. On that + compiler a C program can isse a memory barrier using these + dedicated instructions. According to the GCC manual they + cargo culted this feature form the Itanium ABI so chances + are that other compilers could also support this feature. + But so far GCC is the only compiler that I know to have it. + Also note that this works on non-Itanium machines. + Mon Oct 25 06:21:35 2010 Nobuyoshi Nakada * vsnprintf.c (BSD_vfprintf): prec digits fractal part should be diff --git a/signal.c b/signal.c index 4906e9162a..e2d9d84e4d 100644 --- a/signal.c +++ b/signal.c @@ -25,6 +25,17 @@ typedef LONG rb_atomic_t; # define ATOMIC_INC(var) InterlockedIncrement(&(var)) # define ATOMIC_DEC(var) InterlockedDecrement(&(var)) +#elsif __GNUC__ >= 4 +/* @shyouhei hack to support atomic operations in case of gcc. Gcc + * has its own pseudo-insns to support them. See info, or + * http://gcc.gnu.org/onlinedocs/gcc/Atomic-Builtins.html */ + +typedef unsigned char rb_atomic_t; /* Anything OK */ +# define ATOMIC_TEST(var) __sync_lock_test_and_set(&(var), 0) +# define ATOMIC_SET(var, val) __sync_lock_test_and_set(&(var), (val)) +# define ATOMIC_INC(var) __sync_fetch_and_add(&(var), 1) +# define ATOMIC_DEC(var) __sync_fetch_and_sub(&(var), 1) + #else typedef int rb_atomic_t;