Re: [kvm-devel] [Qemu-devel] [PATCH] use common code for i386 and x86_64

[Aurelien J. <aur...@au...>]

On Wed, Apr 30, 2008 at 05:04:19PM -0300, Glauber Costa wrote:
> There is no reason why should i386 and x86_64 code for rdtsc be different.
> Unify them.

This makes the generated i386 assembly code far more complex (21 
instructions instead of 5).

> ---
>  cpu-all.h |   11 +----------
>  1 files changed, 1 insertions(+), 10 deletions(-)
> 
> diff --git a/cpu-all.h b/cpu-all.h
> index 2a2b197..1c9e2a3 100644
> --- a/cpu-all.h
> +++ b/cpu-all.h
> @@ -930,16 +930,7 @@ static inline int64_t cpu_get_real_ticks(void)
>      return ((int64_t)h << 32) | l;
>  }
>  
> -#elif defined(__i386__)
> -
> -static inline int64_t cpu_get_real_ticks(void)
> -{
> -    int64_t val;
> -    asm volatile ("rdtsc" : "=A" (val));
> -    return val;
> -}
> -
> -#elif defined(__x86_64__)
> +#elif defined(__i386__) || defined(__x86_64__)
>  
>  static inline int64_t cpu_get_real_ticks(void)
>  {
> -- 
> 1.5.0.6
> 
> 
> 
> 

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  .''`.  Aurelien Jarno	            | GPG: 1024D/F1BCDB73
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