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Re: [PATCH] Add a barrier in the double fma implementation
- From: Andreas Schwab <schwab at linux-m68k dot org>
- To: Aurelien Jarno <aurelien at aurel32 dot net>
- Cc: libc-alpha at sources dot redhat dot com, Joseph Myers <joseph at codesourcery dot com>
- Date: Wed, 15 Feb 2012 23:26:19 +0100
- Subject: Re: [PATCH] Add a barrier in the double fma implementation
- References: <20120215192056.GD17446@hall.aurel32.net>
Aurelien Jarno <aurelien@aurel32.net> writes:
> --- a/sysdeps/ieee754/dbl-64/s_fma.c
> +++ b/sysdeps/ieee754/dbl-64/s_fma.c
> @@ -174,6 +174,8 @@
> if ((u.ieee.mantissa1 & 1) == 0)
> u.ieee.mantissa1 |= libc_fetestexcept (FE_INEXACT) != 0;
> v.d = a1 + u.d;
> + /* Ensure the addition is not scheduled after fetestexcept call. */
> + asm volatile ("" : : "m" (v));
math_force_eval (v.d);
Andreas.
--
Andreas Schwab, schwab@linux-m68k.org
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