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invert_packed_extension

p3_field

Function invert_packed_extension 

Source 
pub fn invert_packed_extension<F, EF>(
    packed: EF::ExtensionPacking,
) -> EF::ExtensionPacking
where
    F: Field,
    EF: ExtensionField<F>,
Expand description

Per-lane inverse of a packed extension via Montgomery’s trick. Allocation-free.

Dispatches on F::Packing::WIDTH to a const-generic body that materializes the W lanes via PackedFieldExtension::extract, runs batch_multiplicative_inverse_general over a stack-sized [EF; W] buffer, and rebuilds the packed extension via PackedFieldExtension::from_ext_fn. After monomorphization the match folds to the single live arm.

All PackedField backends in this workspace use WIDTH ∈ {1, 2, 4, 8, 16}; the fallback arm panics if a future backend introduces a different width.