2017-09-21 22:30:11

by Colin King

Subject: [PATCH] i2c: designware: make const array supported_speeds static to shink object code size

From: Colin Ian King <[email protected]>

Don't populate const array supported_speeds on the stack, instead
make it static. Makes the object code smaller by 150 bytes:

Before:
text data bss dec hex filename
8474 1440 0 9914 26ba i2c-designware-platdrv.o

After:
text data bss dec hex filename
8324 1440 0 9764 2624 i2c-designware-platdrv.o

(gcc version 7.2.0 x86_64)

Signed-off-by: Colin Ian King <[email protected]>
---
drivers/i2c/busses/i2c-designware-platdrv.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/i2c/busses/i2c-designware-platdrv.c b/drivers/i2c/busses/i2c-designware-platdrv.c
index 0e65b97842b4..8a7b29b9afbe 100644
--- a/drivers/i2c/busses/i2c-designware-platdrv.c
+++ b/drivers/i2c/busses/i2c-designware-platdrv.c
@@ -257,7 +257,9 @@ static int dw_i2c_plat_probe(struct platform_device *pdev)
u32 acpi_speed, ht = 0;
struct resource *mem;
int i, irq, ret;
- const int supported_speeds[] = { 0, 100000, 400000, 1000000, 3400000 };
+ static const int supported_speeds[] = {
+ 0, 100000, 400000, 1000000, 3400000
+ };

irq = platform_get_irq(pdev, 0);
if (irq < 0)
--
2.14.1

2017-09-22 07:20:13

by Jarkko Nikula

Subject: Re: [PATCH] i2c: designware: make const array supported_speeds static to shink object code size

On 09/22/2017 01:30 AM, Colin King wrote:
> From: Colin Ian King <[email protected]>
>
> Don't populate const array supported_speeds on the stack, instead
> make it static. Makes the object code smaller by 150 bytes:
>
> Before:
> text data bss dec hex filename
> 8474 1440 0 9914 26ba i2c-designware-platdrv.o
>
> After:
> text data bss dec hex filename
> 8324 1440 0 9764 2624 i2c-designware-platdrv.o
>
> (gcc version 7.2.0 x86_64)
>
> Signed-off-by: Colin Ian King <[email protected]>
> ---
> drivers/i2c/busses/i2c-designware-platdrv.c | 4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/i2c/busses/i2c-designware-platdrv.c b/drivers/i2c/busses/i2c-designware-platdrv.c
> index 0e65b97842b4..8a7b29b9afbe 100644
> --- a/drivers/i2c/busses/i2c-designware-platdrv.c
> +++ b/drivers/i2c/busses/i2c-designware-platdrv.c
> @@ -257,7 +257,9 @@ static int dw_i2c_plat_probe(struct platform_device *pdev)
> u32 acpi_speed, ht = 0;
> struct resource *mem;
> int i, irq, ret;
> - const int supported_speeds[] = { 0, 100000, 400000, 1000000, 3400000 };
> + static const int supported_speeds[] = {
> + 0, 100000, 400000, 1000000, 3400000
> + };
>
Oh, this is so easy to forget.

Acked-by: Jarkko Nikula <[email protected]>