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Re: [SG16-Unicode] Performance of C interfaces (was: Re: SG16 meeting summary for August 21st, 2019)

From: Henri Sivonen <hsivonen_at_[hidden]>
Date: Mon, 2 Sep 2019 23:27:53 +0300
On Mon, Sep 2, 2019 at 2:00 AM JeanHeyd Meneide <phdofthehouse_at_[hidden]> wrote:
>
> On Sun, Sep 1, 2019 at 12:07 PM Steve Downey <sdowney_at_[hidden]> wrote:
> >
> > That was, if I recall correctly, about the C standard library interfaces in the Null-terminated multibyte strings section. Basically that the character at a time interfaces are not amenable to vectorization.
...
> With ptr + length, someone can optimize the resulting call as
> much as they like. With null-terminated versions of the function, I am
> skeptical the same performance can be achieved without first calling
> strlen() but I have no experience or data to back up that intuition.

I see.

To me it seems clear that C APIs on this topic should use pointer and length.

-- 
Henri Sivonen
hsivonen_at_[hidden]
https://hsivonen.fi/

Received on 2019-09-02 22:28:08