This is the mail archive of the
gcc-patches@gcc.gnu.org
mailing list for the GCC project.
Re: Remove SHIFT_COUNT_TRUNCATED from double-int.c
- From: Richard Biener <richard dot guenther at gmail dot com>
- To: GCC Patches <gcc-patches at gcc dot gnu dot org>, Richard Sandiford <rdsandiford at googlemail dot com>
- Date: Tue, 5 Nov 2013 12:43:38 +0100
- Subject: Re: Remove SHIFT_COUNT_TRUNCATED from double-int.c
- Authentication-results: sourceware.org; auth=none
- References: <878ux3hpl4 dot fsf at talisman dot default>
On Mon, Nov 4, 2013 at 9:36 PM, Richard Sandiford
<rdsandiford@googlemail.com> wrote:
> ...as suggested by Richard. This means that out-of-range shift values
> produce the same results on all targets at the tree level. The rtl level
> isn't affected since it explicitly truncates the count.
>
> Tested on mips64-linux-gnu. OK to install?
Ok (assuming you didn't pick TARGET_LOONGSON_VECTORS).
Thanks,
Richard.
> Thanks,
> Richard
>
>
> gcc/
> * double-int.c (lshift_double, rshift_double): Remove
> SHIFT_COUNT_TRUNCATED handling.
>
> Index: gcc/double-int.c
> ===================================================================
> --- gcc/double-int.c 2013-09-28 09:41:49.490113799 +0100
> +++ gcc/double-int.c 2013-11-04 15:49:56.963164424 +0000
> @@ -20,7 +20,7 @@ Free Software Foundation; either version
> #include "config.h"
> #include "system.h"
> #include "coretypes.h"
> -#include "tm.h" /* For SHIFT_COUNT_TRUNCATED. */
> +#include "tm.h" /* For BITS_PER_UNIT and *_BIG_ENDIAN. */
> #include "tree.h"
>
> static int add_double_with_sign (unsigned HOST_WIDE_INT, HOST_WIDE_INT,
> @@ -237,9 +237,6 @@ rshift_double (unsigned HOST_WIDE_INT l1
> ? -((unsigned HOST_WIDE_INT) h1 >> (HOST_BITS_PER_WIDE_INT - 1))
> : 0);
>
> - if (SHIFT_COUNT_TRUNCATED)
> - count %= prec;
> -
> if (count >= HOST_BITS_PER_DOUBLE_INT)
> {
> /* Shifting by the host word size is undefined according to the
> @@ -295,9 +292,6 @@ lshift_double (unsigned HOST_WIDE_INT l1
> {
> unsigned HOST_WIDE_INT signmask;
>
> - if (SHIFT_COUNT_TRUNCATED)
> - count %= prec;
> -
> if (count >= HOST_BITS_PER_DOUBLE_INT)
> {
> /* Shifting by the host word size is undefined according to the