From: Andreas Schwab <schwab@linux-m68k.org>
To: Janne Blomqvist <blomqvist.janne@gmail.com>
Cc: GCC Patches <gcc-patches@gcc.gnu.org>,
Fortran List <fortran@gcc.gnu.org>
Subject: Re: [Patch, libfortran] Improve performance of byte swapped IO
Date: Fri, 04 Jan 2013 22:35:00 -0000 [thread overview]
Message-ID: <m2a9somv9s.fsf@igel.home> (raw)
In-Reply-To: <CAO9iq9HB5us6X3faKPt=ZaAcBz_KeVQBTy4ZDiZ6XfeTOVwohA@mail.gmail.com> (Janne Blomqvist's message of "Sat, 5 Jan 2013 00:15:11 +0200")
Janne Blomqvist <blomqvist.janne@gmail.com> writes:
> diff --git a/libgfortran/io/file_pos.c b/libgfortran/io/file_pos.c
> index c8ecc3a..bf2250a 100644
> --- a/libgfortran/io/file_pos.c
> +++ b/libgfortran/io/file_pos.c
> @@ -140,15 +140,21 @@ unformatted_backspace (st_parameter_filepos *fpp, gfc_unit *u)
> }
> else
> {
> + uint32_t u32;
> + uint64_t u64;
> switch (length)
> {
> case sizeof(GFC_INTEGER_4):
> - reverse_memcpy (&m4, p, sizeof (m4));
> + memcpy (&u32, p, sizeof (u32));
> + u32 = __builtin_bswap32 (u32);
> + m4 = *(GFC_INTEGER_4*)&u32;
Isn't that an aliasing violation?
Andreas.
--
Andreas Schwab, schwab@linux-m68k.org
GPG Key fingerprint = 58CA 54C7 6D53 942B 1756 01D3 44D5 214B 8276 4ED5
"And now for something completely different."
next prev parent reply other threads:[~2013-01-04 22:35 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-01-04 22:15 Janne Blomqvist
2013-01-04 22:35 ` Andreas Schwab [this message]
2013-01-05 15:35 ` Richard Biener
2013-01-05 21:13 ` Janne Blomqvist
2013-01-06 11:33 ` Richard Biener
2013-01-11 20:41 ` Janne Blomqvist
2013-01-13 22:44 ` Janne Blomqvist
2013-01-18 22:30 ` Janne Blomqvist
2013-01-22 22:32 ` Thomas Koenig
2013-01-23 21:57 ` Janne Blomqvist
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