[PATCH] mfd: twl4030-irq: remove unnecessary static in twl4030_init_irq()

[PATCH] mfd: twl4030-irq: remove unnecessary static in twl4030_init_irq()

[Gustavo A. R. Silva]

Remove unnecessary static on local variable twl4030_irq_chip.
Such variable is initialized before being used, on every
execution path throughout the function. The static has no
benefit and, removing it reduces the object file size.

This issue was detected using Coccinelle and the following semantic patch:

@bad exists@
position p;
identifier x;
type T;
@@

static T x@p;
...
x = <+...x...+>

@@
identifier x;
expression e;
type T;
position p != bad.p;
@@

-static
 T x@p;
 ... when != x
     when strict
?x = e;

In the following log you can see a significant difference in the object
file size. This log is the output of the size command, before and after
the code change:

before:
   text    data     bss     dec     hex filename
   7076    2400     640   10116    2784 drivers/mfd/twl4030-irq.o

after:
   text    data     bss     dec     hex filename
   7119    2344     320    9783    2637 drivers/mfd/twl4030-irq.o

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
---
 drivers/mfd/twl4030-irq.c             | 2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/drivers/mfd/twl4030-irq.c b/drivers/mfd/twl4030-irq.c
index 378c02d..65d5500 100644
--- a/drivers/mfd/twl4030-irq.c
+++ b/drivers/mfd/twl4030-irq.c
@@ -685,7 +685,7 @@ int twl4030_sih_setup(struct device *dev, int module, int irq_base)
 
 int twl4030_init_irq(struct device *dev, int irq_num)
 {
-	static struct irq_chip	twl4030_irq_chip;
+	struct irq_chip	twl4030_irq_chip;
 	int			status, i;
 	int			irq_base, irq_end, nr_irqs;
 	struct			device_node *node = dev->of_node;
-- 
2.5.0

Re: [PATCH] mfd: twl4030-irq: remove unnecessary static in twl4030_init_irq()

[Lee Jones]

On Mon, 17 Jul 2017, Gustavo A. R. Silva wrote:

> Remove unnecessary static on local variable twl4030_irq_chip.
> Such variable is initialized before being used, on every
> execution path throughout the function. The static has no
> benefit and, removing it reduces the object file size.
> 
> This issue was detected using Coccinelle and the following semantic patch:
> 
> @bad exists@
> position p;
> identifier x;
> type T;
> @@
> 
> static T x@p;
> ...
> x = <+...x...+>
> 
> @@
> identifier x;
> expression e;
> type T;
> position p != bad.p;
> @@
> 
> -static
>  T x@p;
>  ... when != x
>      when strict
> ?x = e;
> 
> In the following log you can see a significant difference in the object
> file size. This log is the output of the size command, before and after
> the code change:
> 
> before:
>    text    data     bss     dec     hex filename
>    7076    2400     640   10116    2784 drivers/mfd/twl4030-irq.o
> 
> after:
>    text    data     bss     dec     hex filename
>    7119    2344     320    9783    2637 drivers/mfd/twl4030-irq.o
> 
> Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
> ---
>  drivers/mfd/twl4030-irq.c             | 2 +-
>  1 files changed, 1 insertions(+), 1 deletions(-)

Applied, thanks.

> diff --git a/drivers/mfd/twl4030-irq.c b/drivers/mfd/twl4030-irq.c
> index 378c02d..65d5500 100644
> --- a/drivers/mfd/twl4030-irq.c
> +++ b/drivers/mfd/twl4030-irq.c
> @@ -685,7 +685,7 @@ int twl4030_sih_setup(struct device *dev, int module, int irq_base)
>  
>  int twl4030_init_irq(struct device *dev, int irq_num)
>  {
> -	static struct irq_chip	twl4030_irq_chip;
> +	struct irq_chip	twl4030_irq_chip;
>  	int			status, i;
>  	int			irq_base, irq_end, nr_irqs;
>  	struct			device_node *node = dev->of_node;

-- 
Lee Jones
Linaro STMicroelectronics Landing Team Lead
Linaro.org │ Open source software for ARM SoCs
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