gcc:
	* config/rs6000/rs6000.h (TARGET_NO_LWSYNC): Define.
	* config/rs6000/rs6000-c.c (rs6000_cpu_cpp_builtins): Define
	__NO_LWSYNC__ if TARGET_NO_LWSYNC.
	* config/rs6000/sync.md (lwsync): Emit plain sync if
	TARGET_NO_LWSYNC.

libstdc++-v3:
	* config/cpu/powerpc/atomic_word.h (_GLIBCXX_WRITE_MEM_BARRIER):
	Use plain sync if __NO_LWSYNC__.

From-SVN: r118961