From c9d933185181cb1cf81bc4c9e5c3a10a5934b017 Mon Sep 17 00:00:00 2001 From: Stefan Hajnoczi Date: Mon, 23 Mar 2015 15:29:28 +0000 Subject: sd: convert sd_normal_command() ffs(3) call to ctz32() ffs() cannot be replaced with ctz32() when the argument might be zero, because ffs(0) returns 0 while ctz32(0) returns 32. The ffs(3) call in sd_normal_command() is a special case though. It can be converted to ctz32() + 1 because the argument is never zero: if (!(req.arg >> 8) || (req.arg >> (ctz32(req.arg & ~0xff) + 1))) { ~~~~~~~~~~~~~~~ ^--------------- req.arg cannot be zero Cc: Markus Armbruster Cc: Peter Crosthwaite Signed-off-by: Stefan Hajnoczi Message-id: 1427124571-28598-7-git-send-email-stefanha@redhat.com Signed-off-by: Kevin Wolf --- hw/sd/sd.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'hw') diff --git a/hw/sd/sd.c b/hw/sd/sd.c index f955265..8abf0c9 100644 --- a/hw/sd/sd.c +++ b/hw/sd/sd.c @@ -796,8 +796,9 @@ static sd_rsp_type_t sd_normal_command(SDState *sd, sd->vhs = 0; /* No response if not exactly one VHS bit is set. */ - if (!(req.arg >> 8) || (req.arg >> ffs(req.arg & ~0xff))) + if (!(req.arg >> 8) || (req.arg >> (ctz32(req.arg & ~0xff) + 1))) { return sd->spi ? sd_r7 : sd_r0; + } /* Accept. */ sd->vhs = req.arg; -- cgit v1.1