summaryrefslogtreecommitdiff
path: root/libstdc++-v3/config/cpu/m68k/atomicity.h
diff options
context:
space:
mode:
authorupstream source tree <ports@midipix.org>2015-03-15 20:14:05 -0400
committerupstream source tree <ports@midipix.org>2015-03-15 20:14:05 -0400
commit554fd8c5195424bdbcabf5de30fdc183aba391bd (patch)
tree976dc5ab7fddf506dadce60ae936f43f58787092 /libstdc++-v3/config/cpu/m68k/atomicity.h
downloadcbb-gcc-4.6.4-554fd8c5195424bdbcabf5de30fdc183aba391bd.tar.bz2
cbb-gcc-4.6.4-554fd8c5195424bdbcabf5de30fdc183aba391bd.tar.xz
obtained gcc-4.6.4.tar.bz2 from upstream website;upstream
verified gcc-4.6.4.tar.bz2.sig; imported gcc-4.6.4 source tree from verified upstream tarball. downloading a git-generated archive based on the 'upstream' tag should provide you with a source tree that is binary identical to the one extracted from the above tarball. if you have obtained the source via the command 'git clone', however, do note that line-endings of files in your working directory might differ from line-endings of the respective files in the upstream repository.
Diffstat (limited to 'libstdc++-v3/config/cpu/m68k/atomicity.h')
-rw-r--r--libstdc++-v3/config/cpu/m68k/atomicity.h132
1 files changed, 132 insertions, 0 deletions
diff --git a/libstdc++-v3/config/cpu/m68k/atomicity.h b/libstdc++-v3/config/cpu/m68k/atomicity.h
new file mode 100644
index 000000000..571125584
--- /dev/null
+++ b/libstdc++-v3/config/cpu/m68k/atomicity.h
@@ -0,0 +1,132 @@
+// Low-level functions for atomic operations: m68k version -*- C++ -*-
+
+// Copyright (C) 2001, 2002, 2003, 2004, 2005, 2009 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library. This library 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; either version 3, or (at your option)
+// any later version.
+
+// This library 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.
+
+// Under Section 7 of GPL version 3, you are granted additional
+// permissions described in the GCC Runtime Library Exception, version
+// 3.1, as published by the Free Software Foundation.
+
+// You should have received a copy of the GNU General Public License and
+// a copy of the GCC Runtime Library Exception along with this program;
+// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
+// <http://www.gnu.org/licenses/>.
+
+#include <ext/atomicity.h>
+
+namespace __gnu_cxx _GLIBCXX_VISIBILITY(default)
+{
+_GLIBCXX_BEGIN_NAMESPACE_VERSION
+
+#if ( defined(__mc68020__) || defined(__mc68030__) \
+ || defined(__mc68040__) || defined(__mc68060__) ) \
+ && !defined(__mcpu32__)
+ // These variants support compare-and-swap.
+ _Atomic_word
+ __attribute__ ((__unused__))
+ __exchange_and_add(volatile _Atomic_word* __mem, int __val) throw ()
+ {
+ register _Atomic_word __result = *__mem;
+ register _Atomic_word __temp;
+ __asm__ __volatile__ ("1: move%.l %0,%1\n\t"
+ "add%.l %3,%1\n\t"
+ "cas%.l %0,%1,%2\n\t"
+ "jne 1b"
+ : "=d" (__result), "=&d" (__temp), "=m" (*__mem)
+ : "d" (__val), "0" (__result), "m" (*__mem));
+ return __result;
+ }
+
+#elif defined(__rtems__)
+ // TAS/JBNE is unsafe on systems with strict priority-based scheduling.
+ // Disable interrupts, which we can do only from supervisor mode.
+ _Atomic_word
+ __attribute__ ((__unused__))
+ __exchange_and_add(volatile _Atomic_word* __mem, int __val) throw ()
+ {
+ _Atomic_word __result;
+ short __level, __tmpsr;
+ __asm__ __volatile__ ("move%.w %%sr,%0\n\tor%.l %0,%1\n\tmove%.w %1,%%sr"
+ : "=d"(__level), "=d"(__tmpsr) : "1"(0x700));
+
+ __result = *__mem;
+ *__mem = __result + __val;
+ __asm__ __volatile__ ("move%.w %0,%%sr" : : "d"(__level));
+
+ return __result;
+ }
+
+#else
+
+ template<int __inst>
+ struct _Atomicity_lock
+ {
+ static volatile unsigned char _S_atomicity_lock;
+ };
+
+ template<int __inst>
+ volatile unsigned char _Atomicity_lock<__inst>::_S_atomicity_lock = 0;
+
+ template volatile unsigned char _Atomicity_lock<0>::_S_atomicity_lock;
+
+ _Atomic_word
+ __attribute__ ((__unused__))
+ __exchange_and_add(volatile _Atomic_word* __mem, int __val) throw ()
+ {
+ _Atomic_word __result;
+
+ // bset with no immediate addressing (not SMP-safe)
+#if defined(__mcfisaa__) || defined(__mcfisaaplus__)
+ __asm__ __volatile__("1: bset.b #7,%0@\n\tjbne 1b"
+ : /* no outputs */
+ : "a"(&_Atomicity_lock<0>::_S_atomicity_lock)
+ : "cc", "memory");
+
+ // CPU32 and CF ISAs B & C support test-and-set (SMP-safe).
+#elif defined(__mcpu32__) || defined(__mcfisab__) || defined (__mcfisac__)
+ __asm__ __volatile__("1: tas %0\n\tjbne 1b"
+ : "+m"(_Atomicity_lock<0>::_S_atomicity_lock)
+ : /* none */
+ : "cc");
+
+ // Use bset with immediate addressing for 68000/68010 (not SMP-safe)
+ // NOTE: TAS is available on the 68000, but unsupported by some Amiga
+ // memory controllers.
+#else
+ __asm__ __volatile__("1: bset.b #7,%0\n\tjbne 1b"
+ : "+m"(_Atomicity_lock<0>::_S_atomicity_lock)
+ : /* none */
+ : "cc");
+#endif
+
+ __result = *__mem;
+ *__mem = __result + __val;
+
+ _Atomicity_lock<0>::_S_atomicity_lock = 0;
+
+ return __result;
+ }
+
+#endif /* TAS / BSET */
+
+ void
+ __attribute__ ((__unused__))
+ __atomic_add(volatile _Atomic_word* __mem, int __val) throw ()
+ {
+ // Careful: using add.l with a memory destination is not
+ // architecturally guaranteed to be atomic.
+ __exchange_and_add(__mem, __val);
+ }
+
+_GLIBCXX_END_NAMESPACE_VERSION
+} // namespace