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reduction
=========

Covers ``sum``, ``max``, ``min`` (reduce over ``axes``). Three variants: ``local``
and ``shared`` (priority 10, discriminated by operand storage scope) and
``sm100_packed`` (priority 20, which pre-empts the others for the thread-scope
float32 case on Blackwell).

.. list-table::
   :header-rows: 1
   :widths: 26 14 60

   * - Variant
     - Prio
     - Lowering
   * - :doc:`reduction/local`
     - 10
     - register src/dst; sequential thread reduction (+ optional warp shuffle)
   * - :doc:`reduction/shared`
     - 10
     - shared src/dst; adaptive group-size ``__shfl_xor`` tree
   * - :doc:`reduction/sm100_packed`
     - 20
     - Blackwell thread-scope fp32 ≥8: packed ``add.f32x2`` / ``max3``/``min3``

.. toctree::
   :maxdepth: 1

   reduction/local
   reduction/shared
   reduction/sm100_packed