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Subject[PATCH 11/13] : Remove redundant test
From: Julia Lawall <julia@diku.dk>

priv is checked not to be NULL near the beginning of the function and not
changed subsequently, making the test redundant.

A simplified version of the semantic patch that makes this change is as
follows: (http://www.emn.fr/x-info/coccinelle/)

// <smpl>
@r exists@
local idexpression x;
expression E;
position p1,p2;
@@

if (x@p1 == NULL || ...) { ... when forall
return ...; }
... when != \(x=E\|x--\|x++\|--x\|++x\|x-=E\|x+=E\|x|=E\|x&=E\|&x\)
(
x@p2 == NULL
|
x@p2 != NULL
)

// another path to the test that is not through p1?
@s exists@
local idexpression r.x;
position r.p1,r.p2;
@@

... when != x@p1
(
x@p2 == NULL
|
x@p2 != NULL
)

@fix depends on !s@
position r.p1,r.p2;
expression x,E;
statement S1,S2;
@@

(
- if ((x@p2 != NULL) || ...)
S1
|
- if ((x@p2 == NULL) && ...) S1
|
- BUG_ON(x@p2 == NULL);
)
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>

---
drivers/usb/gadget/pxa27x_udc.c | 2 +-
drivers/usb/serial/ftdi_sio.c | 16 +++++++---------
2 files changed, 8 insertions(+), 10 deletions(-)

diff --git a/drivers/usb/gadget/pxa27x_udc.c b/drivers/usb/gadget/pxa27x_udc.c
index 990f40f..ee0d7a0 100644
--- a/drivers/usb/gadget/pxa27x_udc.c
+++ b/drivers/usb/gadget/pxa27x_udc.c
@@ -278,7 +278,7 @@ static void pxa_init_debugfs(struct pxa_udc *udc)
goto err_queues;
eps = debugfs_create_file("epstate", 0400, root, udc,
&eps_dbg_fops);
- if (!queues)
+ if (!eps)
goto err_eps;

udc->debugfs_root = root;
diff --git a/drivers/usb/serial/ftdi_sio.c b/drivers/usb/serial/ftdi_sio.c
index ef6cfa5..ad6142e 100644
--- a/drivers/usb/serial/ftdi_sio.c
+++ b/drivers/usb/serial/ftdi_sio.c
@@ -1928,15 +1928,13 @@ static void ftdi_process_read(struct work_struct *work)
/* Compare new line status to the old one, signal if different/
N.B. packet may be processed more than once, but differences
are only processed once. */
- if (priv != NULL) {
- char new_status = data[packet_offset + 0] &
- FTDI_STATUS_B0_MASK;
- if (new_status != priv->prev_status) {
- priv->diff_status |=
- new_status ^ priv->prev_status;
- wake_up_interruptible(&priv->delta_msr_wait);
- priv->prev_status = new_status;
- }
+ char new_status = data[packet_offset + 0] &
+ FTDI_STATUS_B0_MASK;
+ if (new_status != priv->prev_status) {
+ priv->diff_status |=
+ new_status ^ priv->prev_status;
+ wake_up_interruptible(&priv->delta_msr_wait);
+ priv->prev_status = new_status;
}

length = min(PKTSZ, urb->actual_length-packet_offset)-2;

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