Alex Coplan <alex.cop...@arm.com> writes:
> This adds some helpers to access-utils.h for removing accesses from an
> access_array. This is needed by the upcoming aarch64 load/store pair
> fusion pass.
>
> Bootstrapped/regtested as a series on aarch64-linux-gnu, OK for trunk?
>
> gcc/ChangeLog:
>
> * rtl-ssa/access-utils.h (filter_accesses): New.
> (remove_regno_access): New.
> (check_remove_regno_access): New.
> ---
> gcc/rtl-ssa/access-utils.h | 42 ++++++++++++++++++++++++++++++++++++++
> 1 file changed, 42 insertions(+)
>
> diff --git a/gcc/rtl-ssa/access-utils.h b/gcc/rtl-ssa/access-utils.h
> index f078625babf..31259d742d9 100644
> --- a/gcc/rtl-ssa/access-utils.h
> +++ b/gcc/rtl-ssa/access-utils.h
> @@ -78,6 +78,48 @@ drop_memory_access (T accesses)
> return T (arr.begin (), accesses.size () - 1);
> }
>
> +// Filter ACCESSES to return an access_array of only those accesses that
> +// satisfy PREDICATE. Alocate the new array above WATERMARK.
> +template<typename T, typename FilterPredicate>
> +inline T
> +filter_accesses (obstack_watermark &watermark,
> + T accesses,
> + FilterPredicate predicate)
> +{
> + access_array_builder builder (watermark);
> + builder.reserve (accesses.size ());
> + auto it = accesses.begin ();
> + auto end = accesses.end ();
> + for (; it != end; it++)
> + if (predicate (*it))
> + builder.quick_push (*it);
It looks like the last five lines could be simplified to:
for (access_info *access : accesses)
if (!predicate (access))
builder.quick_push (access);
> + return T (builder.finish ());
> +}
> +
> +// Given an array of ACCESSES, remove any access with regno REGNO.
> +// Allocate the new access array above WM.
> +template<typename T>
> +inline T
> +remove_regno_access (obstack_watermark &watermark,
> + T accesses, unsigned int regno)
> +{
> + using Access = decltype (accesses[0]);
> + auto pred = [regno](Access a) { return a->regno () != regno; };
> + return filter_accesses (watermark, accesses, pred);
> +}
> +
> +// As above, but additionally check that we actually did remove an access.
> +template<typename T>
> +inline T
> +check_remove_regno_access (obstack_watermark &watermark,
> + T accesses, unsigned regno)
> +{
> + auto orig_size = accesses.size ();
> + auto result = remove_regno_access (watermark, accesses, regno);
> + gcc_assert (result.size () < orig_size);
> + return result;
> +}
> +
Could you also use the helper to replace:
access_array_builder builder (watermark);
builder.reserve (accesses.size ());
for (access_info *access2 : accesses)
if (!access2->only_occurs_in_notes ())
builder.quick_push (access2);
return builder.finish ();
in remove_note_accesses_base?
OK with those changes, thanks.
Richard
> // If sorted array ACCESSES includes a reference to REGNO, return the
> // access, otherwise return null.
> template<typename T>
