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SubjectRe: [PATCH] ARC: bitops: Remove unecessary operation and value
Date
On 10/21/20 2:12 PM, Gustavo Pimentel wrote:
> The 1-bit shift rotation to the left on x variable located on
> 4 last if statement can be removed because the computed value is will
> not be used afront.

All of constant_fls() is anyhow optimized away at compile time, so this
won't affect any code-gen at all, still this patch is legit.

> Signed-off-by: Gustavo Pimentel <gustavo.pimentel@synopsys.com>

Added to for-curr !

Thx,
-Vineet

> ---
> arch/arc/include/asm/bitops.h | 4 +---
> 1 file changed, 1 insertion(+), 3 deletions(-)
>
> diff --git a/arch/arc/include/asm/bitops.h b/arch/arc/include/asm/bitops.h
> index 50eb3f6..8cddddc 100644
> --- a/arch/arc/include/asm/bitops.h
> +++ b/arch/arc/include/asm/bitops.h
> @@ -297,10 +297,8 @@ static inline int constant_fls(unsigned int x)
> x <<= 2;
> r -= 2;
> }
> - if (!(x & 0x80000000u)) {
> - x <<= 1;
> + if (!(x & 0x80000000u))
> r -= 1;
> - }
> return r;
> }
>

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