[Bug middle-end/107284] New: Option properties Mask infrastructure can be extended with wide_int_bitmask

[Bug middle-end/107284] New: Option properties Mask infrastructure can be extended with wide_int_bitmask

[crazylht at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107284

            Bug ID: 107284
           Summary: Option properties Mask infrastructure can be extended
                    with wide_int_bitmask
           Product: gcc
           Version: 13.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: middle-end
          Assignee: unassigned at gcc dot gnu.org
          Reporter: crazylht at gmail dot com
  Target Milestone: ---

For x86, as more and more ISAs are introduced, we're almost running out of
ix86_isa_flags2, a ix86_isa_flags3 needs to be introduced, that caused
maintainance difficulty since there're depenedence between bits in different
isa_flag(and several values used as same purpose for isa bit mask), it would be
nice if we can introduce wide_int_bit_mask in the
opth-gen.awk/opts-functions.awk ..etc, extend wide_int_bit_mask to 256 bits,
and overload bit set/shift in wide_int_bitmask.h. So the backend can be
released from maintain those "overloads" for mask bits.

[Bug middle-end/107284] Option properties Mask infrastructure can be extended with wide_int_bitmask

[marxin at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107284

Martin Liška <marxin at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |ASSIGNED
                 CC|                            |marxin at gcc dot gnu.org
           Assignee|unassigned at gcc dot gnu.org      |marxin at gcc dot gnu.org
   Last reconfirmed|                            |2022-10-17
     Ever confirmed|0                           |1

--- Comment #1 from Martin Liška <marxin at gcc dot gnu.org> ---
I welcome the idea and I can take a look at it during stage3.

[Bug middle-end/107284] Option properties Mask infrastructure can be extended with wide_int_bitmask

[marxin at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107284

Martin Liška <marxin at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Assignee|marxin at gcc dot gnu.org          |unassigned at gcc dot gnu.org
             Status|ASSIGNED                    |NEW

--- Comment #2 from Martin Liška <marxin at gcc dot gnu.org> ---
So apparently it won't be so simple as cl_target_option is a GGC structure and
thus wide_int_bitmask needs to use GTY. However, I get the following errors:

/home/marxin/Programming/gcc/gcc/wide-int-bitmask.h:26: undefined type
`constexpr'
/home/marxin/Programming/gcc/gcc/wide-int-bitmask.h:26: undefined type
`constexpr'
/home/marxin/Programming/gcc/gcc/wide-int-bitmask.h:26: undefined type
`constexpr'

Just for the record, right now, there are 26 free bits available in
ix86_isa_flags2.

[Bug middle-end/107284] Option properties Mask infrastructure can be extended with wide_int_bitmask

[marxin at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=107284

--- Comment #3 from Martin Liška <marxin at gcc dot gnu.org> ---
Well, the ideal option would be std::bitset<N> which would replace
host_wide_bitset.