Convert ffs() != 0 callers to ctz32()

There are a number of ffs(3) callers that do roughly:

  bit = ffs(val);
  if (bit) {
      do_something(bit - 1);
  }

This pattern can be converted to ctz32() like this:

  zeroes = ctz32(val);
  if (zeroes != 32) {
      do_something(zeroes);
  }

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 1427124571-28598-6-git-send-email-stefanha@redhat.com
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

1 files changed, 4 insertions, 4 deletions

diff --git a/hw/intc/allwinner-a10-pic.c b/hw/intc/allwinner-a10-pic.c
index de820b9723..eed7621f13 100644
--- a/hw/intc/allwinner-a10-pic.c
+++ b/hw/intc/allwinner-a10-pic.c
@@ -23,7 +23,7 @@
 static void aw_a10_pic_update(AwA10PICState *s)
 {
     uint8_t i;
-    int irq = 0, fiq = 0, pending;
+    int irq = 0, fiq = 0, zeroes;
 
     s->vector = 0;
 
@@ -32,9 +32,9 @@ static void aw_a10_pic_update(AwA10PICState *s)
         fiq |= s->select[i] & s->irq_pending[i] & ~s->mask[i];
 
         if (!s->vector) {
-            pending = ffs(s->irq_pending[i] & ~s->mask[i]);
-            if (pending) {
-                s->vector = (i * 32 + pending - 1) * 4;
+            zeroes = ctz32(s->irq_pending[i] & ~s->mask[i]);
+            if (zeroes != 32) {
+                s->vector = (i * 32 + zeroes) * 4;
             }
         }
     }