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From: Richard Henderson <rth@twiddle.net>
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Date: Sun, 9 Jul 2017 10:48:27 -1000
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Subject: Re: [Qemu-devel] [PATCH 19/22] tcg: introduce tcg_context_clone
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To: "Emilio G. Cota" <cota@braap.org>, qemu-devel@nongnu.org

On 07/08/2017 09:50 PM, Emilio G. Cota wrote:
> @@ -409,6 +411,18 @@ void tcg_context_init(TCGContext *s)
>   }
>   
>   /*
> + * Clone the initial TCGContext. Used by TCG threads to copy the TCGContext
> + * set up by their parent thread via tcg_context_init().
> + */
> +void tcg_context_clone(TCGContext *s)
> +{
> +    if (unlikely(tcg_init_ctx == NULL || tcg_init_ctx == s)) {
> +        tcg_abort();
> +    }
> +    memcpy(s, tcg_init_ctx, sizeof(*s));
> +}

Under what conditions will this be called?  How much of this might you need to 
zero out again after the fact?


r~