From 41074f3d3ff0e9a3c6f638627c12ebbf6d757cea Mon Sep 17 00:00:00 2001 From: Paolo Bonzini Date: Mon, 23 Mar 2015 15:29:29 +0000 Subject: omap_intc: convert ffs(3) to ctz32() in omap_inth_sir_update() Rewrite the loop using level &= level - 1 to clear the least significant bit after each iteration. This simplifies the loop and makes it easy to replace ffs(3) with ctz32(). Cc: Peter Maydell Signed-off-by: Paolo Bonzini Signed-off-by: Stefan Hajnoczi Message-id: 1427124571-28598-8-git-send-email-stefanha@redhat.com Signed-off-by: Kevin Wolf --- hw/intc/omap_intc.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) (limited to 'hw') diff --git a/hw/intc/omap_intc.c b/hw/intc/omap_intc.c index ad3931c112..e9b38a3c63 100644 --- a/hw/intc/omap_intc.c +++ b/hw/intc/omap_intc.c @@ -60,7 +60,7 @@ struct omap_intr_handler_s { static void omap_inth_sir_update(struct omap_intr_handler_s *s, int is_fiq) { - int i, j, sir_intr, p_intr, p, f; + int i, j, sir_intr, p_intr, p; uint32_t level; sir_intr = 0; p_intr = 255; @@ -72,14 +72,15 @@ static void omap_inth_sir_update(struct omap_intr_handler_s *s, int is_fiq) for (j = 0; j < s->nbanks; ++j) { level = s->bank[j].irqs & ~s->bank[j].mask & (is_fiq ? s->bank[j].fiq : ~s->bank[j].fiq); - for (f = ffs(level), i = f - 1, level >>= f - 1; f; i += f, - level >>= f) { + + while (level != 0) { + i = ctz32(level); p = s->bank[j].priority[i]; if (p <= p_intr) { p_intr = p; sir_intr = 32 * j + i; } - f = ffs(level >> 1); + level &= level - 1; } } s->sir_intr[is_fiq] = sir_intr; -- cgit v1.2.3