OPTIM: epoll: use a temp variable for intermediary flag computations

Playing with fdtab[fd].ev makes gcc constantly reload the pointers
because it does not know they don't alias. Use a temporary variable
instead. This saves a few operations in the fast path.

diff --git a/src/ev_epoll.c b/src/ev_epoll.c
index a9b841035cfc136499ce1fe51650763c1eb60334..b858e18ae65bb7251bab58788e8aae640734f54b 100644 (file)
--- a/src/ev_epoll.c
+++ b/src/ev_epoll.c
@@ -137,7 +137,8 @@ REGPRM2 static void _do_poll(struct poller *p, int exp)
        /* process polled events */
 
        for (count = 0; count < status; count++) {
-               int e = epoll_events[count].events;
+               unsigned char n;
+               unsigned char e = epoll_events[count].events;
                fd = epoll_events[count].data.fd;
 
                if (!fdtab[fd].owner)
@@ -150,18 +151,22 @@ REGPRM2 static void _do_poll(struct poller *p, int exp)
                if (EPOLLIN == FD_POLL_IN && EPOLLOUT == FD_POLL_OUT &&
                    EPOLLPRI == FD_POLL_PRI && EPOLLERR == FD_POLL_ERR &&
                    EPOLLHUP == FD_POLL_HUP) {
-                       fdtab[fd].ev |= e & (EPOLLIN|EPOLLOUT|EPOLLPRI|EPOLLERR|EPOLLHUP);
+                       n = e & (EPOLLIN|EPOLLOUT|EPOLLPRI|EPOLLERR|EPOLLHUP);
                }
                else {
-                       fdtab[fd].ev |=
-                               ((e & EPOLLIN ) ? FD_POLL_IN  : 0) |
+                       n =     ((e & EPOLLIN ) ? FD_POLL_IN  : 0) |
                                ((e & EPOLLPRI) ? FD_POLL_PRI : 0) |
                                ((e & EPOLLOUT) ? FD_POLL_OUT : 0) |
                                ((e & EPOLLERR) ? FD_POLL_ERR : 0) |
                                ((e & EPOLLHUP) ? FD_POLL_HUP : 0);
                }
 
-               if (fdtab[fd].iocb && fdtab[fd].ev) {
+               if (!n)
+                       continue;
+
+               fdtab[fd].ev |= n;
+
+               if (fdtab[fd].iocb) {
                        int new_updt, old_updt = fd_nbupdt; /* Save number of updates to detect creation of new FDs. */
 
                        /* Mark the events as speculative before processing