On Mon, Apr 17, 2023 at 11:44 AM Aldy Hernandez via Gcc-patches
<gcc-patches@gcc.gnu.org> wrote:
>
> I'm about to add one more use of the same snippet of code, for a total
> of 4 identical calculations in the code base.
>
> This seems safe enough even before the release, since this file hardly
> changes and I'm pretty much the only one who's touched it this year.
>
> OK for trunk?
>
> gcc/ChangeLog:
>
> * wide-int.h (WIDE_INT_MAX_HWIS): New.
> (class fixed_wide_int_storage): Use it.
> (trailing_wide_ints <N>::set_precision): Use it.
> (trailing_wide_ints <N>::extra_size): Use it.
> ---
> gcc/wide-int.h | 12 +++++++-----
> 1 file changed, 7 insertions(+), 5 deletions(-)
>
> diff --git a/gcc/wide-int.h b/gcc/wide-int.h
> index a450a744c9f..6be343c0eb5 100644
> --- a/gcc/wide-int.h
> +++ b/gcc/wide-int.h
> @@ -264,6 +264,10 @@ along with GCC; see the file COPYING3. If not see
> /* The number of HWIs needed to store an offset_int. */
> #define OFFSET_INT_ELTS (ADDR_MAX_PRECISION / HOST_BITS_PER_WIDE_INT)
>
> +/* The max number of HWIs needed to store a wide_int of PRECISION. */
> +#define WIDE_INT_MAX_HWIS(PRECISION) \
> + ((PRECISION + HOST_BITS_PER_WIDE_INT - 1) / HOST_BITS_PER_WIDE_INT)
Does it make sense to use an constexpr inline function instead of a
define here since GCC is written in C++11 after all?
That is:
constexpr inline unsigned WIDE_INT_MAX_HWIS(unsigned precision)
{
return ((precision + HOST_BITS_PER_WIDE_INT - 1) / HOST_BITS_PER_WIDE_INT);
}
Thanks,
Andrew Pinski
> +
> /* The type of result produced by a binary operation on types T1 and T2.
> Defined purely for brevity. */
> #define WI_BINARY_RESULT(T1, T2) \
> @@ -1214,7 +1218,7 @@ template <int N>
> class GTY(()) fixed_wide_int_storage
> {
> private:
> - HOST_WIDE_INT val[(N + HOST_BITS_PER_WIDE_INT + 1) /
> HOST_BITS_PER_WIDE_INT];
> + HOST_WIDE_INT val[WIDE_INT_MAX_HWIS (N)];
> unsigned int len;
>
> public:
> @@ -1475,8 +1479,7 @@ trailing_wide_ints <N>::set_precision (unsigned int
> precision,
> gcc_checking_assert (num_elements <= N);
> m_num_elements = num_elements;
> m_precision = precision;
> - m_max_len = ((precision + HOST_BITS_PER_WIDE_INT - 1)
> - / HOST_BITS_PER_WIDE_INT);
> + m_max_len = WIDE_INT_MAX_HWIS (precision);
> }
>
> /* Return a reference to element INDEX. */
> @@ -1505,8 +1508,7 @@ inline size_t
> trailing_wide_ints <N>::extra_size (unsigned int precision,
> unsigned int num_elements)
> {
> - unsigned int max_len = ((precision + HOST_BITS_PER_WIDE_INT - 1)
> - / HOST_BITS_PER_WIDE_INT);
> + unsigned int max_len = WIDE_INT_MAX_HWIS (precision);
> gcc_checking_assert (num_elements <= N);
> return (num_elements * max_len - 1) * sizeof (HOST_WIDE_INT);
> }
> --
> 2.39.2
>
