On Mon, May 19, 2025 at 4:14 PM Konstantinos Eleftheriou
<konstantinos.elefther...@vrull.eu> wrote:
>
> This patch adds the `bitmap_is_range_set_p` function in sbitmap,
> which checks if all the bits in a range are set. This function
> calls `bitmap_bit_in_range_p_1`, which has been updated to use
> the `any_inverted` parameter. When `any_inverted` is true, the helper
> function checks if any of the bits in the range is unset, instead of
> checking the opposite.
>
> Function `bitmap_bit_in_range_p` has been updated to call
> `bitmap_bit_in_range_p_1` with the `any_inverted` parameter
> set to false, retaining its previous functionality.
>
> Function `bitmap_is_range_set_p` calls `bitmap_bit_in_range_p_1`
> with `any_inverted` set to true and returns the negation of the
> result, i.e. true if all the bits in the range are set.
>
> gcc/ChangeLog:
>
> * sbitmap.cc (bitmap_bit_in_range_p_1): Added the `any_inverted`
> parameter and changed the logic to check if any of the bits in
> the range is unset, when the value of the parameter is "true".
> (bitmap_is_range_set_p): New function.
> (bitmap_bit_in_range_p): Call and return the result of
> `bitmap_bit_in_range_p_1` with the `any_inverted` parameter set
> to false.
> * sbitmap.h (bitmap_is_range_set_p): New function.
>
> Signed-off-by: Konstantinos Eleftheriou <konstantinos.elefther...@vrull.eu>
> ---
>
> (no changes since v1)
>
> gcc/sbitmap.cc | 27 ++++++++++++++++++++-------
> gcc/sbitmap.h | 1 +
> 2 files changed, 21 insertions(+), 7 deletions(-)
>
> diff --git a/gcc/sbitmap.cc b/gcc/sbitmap.cc
> index 94f2bbd6c8fd..99f1db540ab6 100644
> --- a/gcc/sbitmap.cc
> +++ b/gcc/sbitmap.cc
> @@ -326,12 +326,13 @@ bitmap_set_range (sbitmap bmap, unsigned int start,
> unsigned int count)
> bmap->elms[start_word] |= mask;
> }
>
> -/* Return TRUE if any bit between START and END inclusive is set within
> - the simple bitmap BMAP. Return FALSE otherwise. */
> +/* Helper function for bitmap_bit_in_range_p and bitmap_is_range_set_p.
> + If ANY_INVERTED is true, the function checks if any bit in the range
> + is unset. */
>
> bool
> bitmap_bit_in_range_p_1 (const_sbitmap bmap, unsigned int start,
> - unsigned int end)
> + unsigned int end, bool any_inverted)
> {
> gcc_checking_assert (start <= end);
> bitmap_check_index (bmap, end);
> @@ -351,7 +352,8 @@ bitmap_bit_in_range_p_1 (const_sbitmap bmap, unsigned int
> start,
>
> SBITMAP_ELT_TYPE low_mask = ((SBITMAP_ELT_TYPE)1 << start_bitno) - 1;
> SBITMAP_ELT_TYPE mask = high_mask - low_mask;
> - if (bmap->elms[start_word] & mask)
> + const SBITMAP_ELT_TYPE expected_partial = any_inverted ? mask : 0;
> + if ((bmap->elms[start_word] & mask) != expected_partial)
> return true;
> start_word++;
> }
> @@ -361,9 +363,10 @@ bitmap_bit_in_range_p_1 (const_sbitmap bmap, unsigned
> int start,
>
> /* Now test words at a time until we hit a partial word. */
> unsigned int nwords = (end_word - start_word);
> + const SBITMAP_ELT_TYPE expected = any_inverted ? ~(SBITMAP_ELT_TYPE)0 : 0;
> while (nwords)
> {
> - if (bmap->elms[start_word])
> + if (bmap->elms[start_word] != expected)
> return true;
> start_word++;
> nwords--;
> @@ -373,7 +376,17 @@ bitmap_bit_in_range_p_1 (const_sbitmap bmap, unsigned
> int start,
> SBITMAP_ELT_TYPE mask = ~(SBITMAP_ELT_TYPE)0;
> if (end_bitno + 1 < SBITMAP_ELT_BITS)
> mask = ((SBITMAP_ELT_TYPE)1 << (end_bitno + 1)) - 1;
> - return (bmap->elms[start_word] & mask) != 0;
> + const SBITMAP_ELT_TYPE expected_partial = any_inverted ? mask : 0;
> + return (bmap->elms[start_word] & mask) != expected_partial;
> +}
> +
> +/* Return TRUE if all bits between START and END inclusive are set within
> + the simple bitmap BMAP. Return FALSE otherwise. */
> +
> +bool
> +bitmap_is_range_set_p (const_sbitmap bmap, unsigned int start, unsigned int
> end)
> +{
> + return !bitmap_bit_in_range_p_1 (bmap, start, end, true);
> }
>
> /* Return TRUE if any bit between START and END inclusive is set within
> @@ -382,7 +395,7 @@ bitmap_bit_in_range_p_1 (const_sbitmap bmap, unsigned int
> start,
> bool
> bitmap_bit_in_range_p (const_sbitmap bmap, unsigned int start, unsigned int
> end)
> {
> - return bitmap_bit_in_range_p_1 (bmap, start, end);
> + return bitmap_bit_in_range_p_1 (bmap, start, end, false);
> }
>
> #if GCC_VERSION < 3400
> diff --git a/gcc/sbitmap.h b/gcc/sbitmap.h
> index 66f9e138503c..4ff93e7a98f9 100644
> --- a/gcc/sbitmap.h
> +++ b/gcc/sbitmap.h
> @@ -288,6 +288,7 @@ extern bool bitmap_ior (sbitmap, const_sbitmap,
> const_sbitmap);
> extern bool bitmap_xor (sbitmap, const_sbitmap, const_sbitmap);
> extern bool bitmap_subset_p (const_sbitmap, const_sbitmap);
> extern bool bitmap_bit_in_range_p (const_sbitmap, unsigned int, unsigned
> int);
> +extern bool bitmap_is_range_set_p (const_sbitmap, unsigned int, unsigned
> int);
To me those sound like doing the same thing. Maybe all_bits_in_range_p vs.
any_bit_in_range_p?
>
> extern int bitmap_first_set_bit (const_sbitmap);
> extern int bitmap_last_set_bit (const_sbitmap);
> --
> 2.49.0
>
