[10/12] Add femode_t functions: s390
Yury Norov
ynorov@caviumnetworks.com
Sat Sep 3 14:38:00 GMT 2016
On Fri, Sep 02, 2016 at 09:58:37PM +0000, Joseph Myers wrote:
[...]
> diff --git a/sysdeps/s390/fpu/fesetmode.c b/sysdeps/s390/fpu/fesetmode.c
> new file mode 100644
> index 0000000..8feb9b6
> --- /dev/null
> +++ b/sysdeps/s390/fpu/fesetmode.c
> @@ -0,0 +1,38 @@
> +/* Install given floating-point control modes. S/390 version.
> + Copyright (C) 2016 Free Software Foundation, Inc.
> + This file is part of the GNU C Library.
> +
> + The GNU C Library is free software; you can redistribute it and/or
> + modify it under the terms of the GNU Lesser General Public
> + License as published by the Free Software Foundation; either
> + version 2.1 of the License, or (at your option) any later version.
> +
> + The GNU C Library is distributed in the hope that it will be useful,
> + but WITHOUT ANY WARRANTY; without even the implied warranty of
> + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
> + Lesser General Public License for more details.
> +
> + You should have received a copy of the GNU Lesser General Public
> + License along with the GNU C Library; if not, see
> + <http://www.gnu.org/licenses/>. */
> +
> +#include <fenv.h>
> +#include <fpu_control.h>
> +#include <fenv_libc.h>
> +
> +#define FPC_STATUS (FPC_FLAGS_MASK | FPC_DXC_MASK)
> +
> +int
> +fesetmode (const femode_t *modep)
> +{
> + fpu_control_t fpc;
> +
> + _FPU_GETCW (fpc);
> + if (modep == FE_DFL_ENV)
> + fpc = (fpc & FPC_STATUS) | _FPU_DEFAULT;
> + else
> + fpc = (fpc & FPC_STATUS) | (*modep & ~FPC_STATUS);
You do fpc = (fpc & FPC_STATUS) in both branches of condition.
So you can save few instruction if move this snippet upper,
and also increase readability.
Not sure how much gcc-s390 is smart, maybe it can do it for you, but
readability is still in case.
> + _FPU_SETCW (fpc);
> +
> + return 0;
> +}
>
> --
> Joseph S. Myers
> joseph@codesourcery.com
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