Am 28.08.2015 um 15:49 schrieb Alexander Kuleshov:
> We can use .rept directive to simplify/decrease assembly code
> that makes storing and loading floating point registers in the
> arch/s390/kernel/swsusp.S.
> 
> The resulting code after the patch is the same that before
> 
>  2c4: 68 00 d2 00             ld      %f0,512(%r13)
>  2c8: 68 10 d2 08             ld      %f1,520(%r13)
>  2cc: 68 20 d2 10             ld      %f2,528(%r13)
>  2d0: 68 30 d2 18             ld      %f3,536(%r13)
>  2d4: 68 40 d2 20             ld      %f4,544(%r13)
>  2d8: 68 50 d2 28             ld      %f5,552(%r13)
>  2dc: 68 60 d2 30             ld      %f6,560(%r13)
>  2e0: 68 70 d2 38             ld      %f7,568(%r13)
>  2e4: 68 80 d2 40             ld      %f8,576(%r13)
>  2e8: 68 90 d2 48             ld      %f9,584(%r13)
>  2ec: 68 a0 d2 50             ld      %f10,592(%r13)
>  2f0: 68 b0 d2 58             ld      %f11,600(%r13)
>  2f4: 68 c0 d2 60             ld      %f12,608(%r13)
>  2f8: 68 d0 d2 68             ld      %f13,616(%r13)
>  2fc: 68 e0 d2 70             ld      %f14,624(%r13)
>  300: 68 f0 d2 78             ld      %f15,632(%r13)
> 
> Signed-off-by: Alexander Kuleshov <kuleshovm...@gmail.com>
> ---
>  arch/s390/kernel/swsusp.S | 49 
> ++++++++++++++++-------------------------------
>  1 file changed, 17 insertions(+), 32 deletions(-)
> 
> diff --git a/arch/s390/kernel/swsusp.S b/arch/s390/kernel/swsusp.S
> index ca62946..8011e14 100644
> --- a/arch/s390/kernel/swsusp.S
> +++ b/arch/s390/kernel/swsusp.S
> @@ -48,22 +48,15 @@ ENTRY(swsusp_arch_suspend)
>       /* Store registers */
>       mvc     0x318(4,%r1),__SF_EMPTY(%r15)   /* move prefix to lowcore */
>       stfpc   0x31c(%r1)                      /* store fpu control */
> -     std     0,0x200(%r1)                    /* store f0 */
> -     std     1,0x208(%r1)                    /* store f1 */
> -     std     2,0x210(%r1)                    /* store f2 */
> -     std     3,0x218(%r1)                    /* store f3 */
> -     std     4,0x220(%r1)                    /* store f4 */
> -     std     5,0x228(%r1)                    /* store f5 */
> -     std     6,0x230(%r1)                    /* store f6 */
> -     std     7,0x238(%r1)                    /* store f7 */
> -     std     8,0x240(%r1)                    /* store f8 */
> -     std     9,0x248(%r1)                    /* store f9 */
> -     std     10,0x250(%r1)                   /* store f10 */
> -     std     11,0x258(%r1)                   /* store f11 */
> -     std     12,0x260(%r1)                   /* store f12 */
> -     std     13,0x268(%r1)                   /* store f13 */
> -     std     14,0x270(%r1)                   /* store f14 */
> -     std     15,0x278(%r1)                   /* store f15 */
> +
> +     /* store f0..f15 floating point registers */
> +     .set i, 0
> +     .set f, 0x200
> +     .rept 16
> +     std i, f(%r1)
> +     .set i, (i+1)
> +     .set f, (f+0x8)
> +     .endr

I personally find the existing code easier to read, especially as it matches the
assembler output and I can directly where the slots are, (e.g. f11 is 0x258)

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