GitLab

* Softcap v2 (fwd only).

* Some missing interface + remove overrides in tests.

When user send `out` as a parameter of the function
`seqlenq_ngroups_swapped` with parameters that trigger,
the CHECK_SHAPE is incorrect (since q shape is modified.)

Co-authored-by: zl <zl@deepseek.com>

* Support unpadded LSE layout.
Co-authored-by: Xinfeng Xie <xfxie.ceca@gmail.com>
Co-authored-by: Jianyu Huang <hjyahead@gmail.com>

* Cleanup

* Fix unpadded LSE on split-kv path

* Fix formatting and comments

* Fix inline vs forceinline

---------
Co-authored-by: Xinfeng Xie <xfxie.ceca@gmail.com>
Co-authored-by: Jianyu Huang <hjyahead@gmail.com>

* Enable paged attention in varlen forward

* Format + fix padding

For faster and smaller builds in some simple cases,
provide switches to allow disabling
-backward
-alibi
-uneven k
-dropout
-local attention
Co-authored-by: Jeremy Francis Reizenstein <bottler@users.noreply.github.com>

Co-authored-by: ljss <450993438@qq.com>

* Add split-k, M<->H to varseq path

* skip M<->H when dropout>0, fix LSE