[PATCH 1/11] drivers/ide: Move a dereference below a NULL test

From: Julia Lawall
Date: Tue Dec 16 2008 - 10:12:17 EST


From: Julia Lawall <julia@xxxxxxx>

In each case, if the NULL test is necessary, then the dereference should be
moved below the NULL test.

The semantic patch that makes this change is as follows:
(http://www.emn.fr/x-info/coccinelle/)

// <smpl>
@@
type T;
expression E;
identifier i,fld;
statement S;
@@

- T i = E->fld;
+ T i;
... when != E
when != i
if (E == NULL) S
+ i = E->fld;
// </smpl>

Signed-off-by: Julia Lawall <julia@xxxxxxx>

---
drivers/ide/cs5530.c | 3 ++-
drivers/ide/sc1200.c | 3 ++-
2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/ide/cs5530.c b/drivers/ide/cs5530.c
index 53f079c..d8ede85 100644
--- a/drivers/ide/cs5530.c
+++ b/drivers/ide/cs5530.c
@@ -81,11 +81,12 @@ static u8 cs5530_udma_filter(ide_drive_t *drive)
{
ide_hwif_t *hwif = drive->hwif;
ide_drive_t *mate = ide_get_pair_dev(drive);
- u16 *mateid = mate->id;
+ u16 *mateid;
u8 mask = hwif->ultra_mask;

if (mate == NULL)
goto out;
+ mateid = mate->id;

if (ata_id_has_dma(mateid) && __ide_dma_bad_drive(mate) == 0) {
if ((mateid[ATA_ID_FIELD_VALID] & 4) &&
diff --git a/drivers/ide/sc1200.c b/drivers/ide/sc1200.c
index f1a8758..ec7f766 100644
--- a/drivers/ide/sc1200.c
+++ b/drivers/ide/sc1200.c
@@ -104,11 +104,12 @@ static u8 sc1200_udma_filter(ide_drive_t *drive)
{
ide_hwif_t *hwif = drive->hwif;
ide_drive_t *mate = ide_get_pair_dev(drive);
- u16 *mateid = mate->id;
+ u16 *mateid;
u8 mask = hwif->ultra_mask;

if (mate == NULL)
goto out;
+ mateid = mate->id;

if (ata_id_has_dma(mateid) && __ide_dma_bad_drive(mate) == 0) {
if ((mateid[ATA_ID_FIELD_VALID] & 4) &&
--
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