__INSN_BARRIER(3) | Library Functions Manual | __INSN_BARRIER(3) |
__insn_barrier
—
#include <sys/cdefs.h>
void
__insn_barrier
();
__insn_barrier
() macro prevents GCC from moving code
across the barrier. In other words, the compiler is not allowed to reorder
read and write commands below the barrier with the code preceding the barrier.
Like with the volatile type qualifier,
__insn_barrier
() may be necessary in some corner cases
to prevent the compiler from misoptimizing.
Paul E. McKenney, Memory Barriers: a Hardware View for Software Hackers, http://www.rdrop.com/users/paulmck/scalability/paper/whymb.2010.06.07c.pdf, June 7, 2010.
__insn_barrier
() macro first appeared in
NetBSD 2.0.
January 2, 2011 | NetBSD 9.2 |