linux-kernel - Re: [PATCH v2 next 04/11] tools/nolibc/printf: Output pad characters in 16 byte chunks

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Message-ID: <aYioTsLEytuc1uue@1wt.eu>
Date: Sun, 8 Feb 2026 16:14:22 +0100
From: Willy Tarreau <w@....eu>
To: David Laight <david.laight.linux@...il.com>
Cc: Thomas Weißschuh <linux@...ssschuh.net>,
        linux-kernel@...r.kernel.org, Cheng Li <lechain@...il.com>
Subject: Re: [PATCH v2 next 04/11] tools/nolibc/printf: Output pad characters
 in 16 byte chunks

On Sat, Feb 07, 2026 at 11:43:05PM +0000, David Laight wrote:
> On Sat, 7 Feb 2026 20:38:36 +0100
> Willy Tarreau <w@....eu> wrote:
> 
> > On Fri, Feb 06, 2026 at 07:11:14PM +0000, david.laight.linux@...il.com wrote:
> > > From: David Laight <david.laight.linux@...il.com>
> > > 
> > > Simple to do and saves calls to the callback function.  
> > 
> > +20 bytes here but OK for me.
> 
> I think some of those come back when I change all the variables to 'int'.
> Some, but not all, is because width is 32bit but len is 64bit.
> The final change that did:
> 	width -= len;
> 	...
> 	while (width > 0)
> saved a surprising amount provided the ... contained some code.
> Breath on the code (or compiler version) and you easily get +/-60 bytes.

Yeah I tried as well with size_t (since compilers generally do not like
mixing data types and tend to place conversions every few instructions),
but some constants become larger and the code inflates as well.

Willy