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Re: [PATCH] byteswap.h: fix gcc ver test for __builtin_bswap32

From: Andreas Schwab <schwab at suse dot de>
To: Rich Felker <dalias at aerifal dot cx>
Cc: libc-alpha at sourceware dot org
Date: Thu, 29 Nov 2012 09:47:31 +0100
Subject: Re: [PATCH] byteswap.h: fix gcc ver test for __builtin_bswap32
References: <1354162043-16829-1-git-send-email-vapier@gentoo.org><20121129041611.GW20323@brightrain.aerifal.cx>

Rich Felker <dalias@aerifal.cx> writes:

> Using __builtin_bswap32 is utterly useless. Ever since the early to
> mid 4.x series, GCC generates the proper optimized code for the naive
> direct expression of bswap32 in C.

You need to be a bit careful about the exact form, though, and
__builtin_bswap32 doesn't require duplicating the argument.

Andreas.

-- 
Andreas Schwab, SUSE Labs, schwab@suse.de
GPG Key fingerprint = 0196 BAD8 1CE9 1970 F4BE  1748 E4D4 88E3 0EEA B9D7
"And now for something completely different."

References:
- [PATCH] byteswap.h: fix gcc ver test for __builtin_bswap32
  - From: Mike Frysinger
- Re: [PATCH] byteswap.h: fix gcc ver test for __builtin_bswap32
  - From: Rich Felker

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