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Date: Fri, 30 Dec 2022 16:31:31 +0200
Message-Id: <835ydt6jzw.fsf@gnu.org>
From: Eli Zaretskii <eliz@gnu.org>
To: Simon Marchi <simark@simark.ca>
Cc: tom@tromey.com, gdb-patches@sourceware.org, luis.machado@arm.com
In-Reply-To: <587b899f-0f93-530a-7313-d4e1f9e501b9@simark.ca> (message from
	Simon Marchi on Thu, 29 Dec 2022 15:22:31 -0500)
Subject: Re: Two observations using GDB 13 snapshot
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> Date: Thu, 29 Dec 2022 15:22:31 -0500
> Cc: gdb-patches@sourceware.org, luis.machado@arm.com
> From: Simon Marchi <simark@simark.ca>
> 
> 
> It looks like we spend a lot of time sorting the vector of index
> entries.  We spend a lot of time in tolower.

Why do we need to use tolower in sorting here? is the sorting order
case-insensitive or something?

> Googling a bit, it looks
> like tolower can be slow on Windows when a locale (other than "C") is
> used:
> 
> https://stackoverflow.com/questions/36686381/windows-c-runtime-toupper-slow-when-locale-set
> https://bugs.php.net/bug.php?id=45265

I couldn't see any numbers there about the performance of tolower
itself, i.e. how many ms per call does it take on Windows vs glibc.
But if someone can show a patch to try to eliminate the calls to
tolower, I can try and see if it affects the processing time in this
scenario.

Thanks.