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5136 commits behind the upstream repository.
Jade's avatar
Jade authored
This patch improves the algorithm to sort lists in base.
It does so using two strategies:

1) Use a four-way-merge instead of the 'default' two-way-merge.
This is able to save comparisons and allocations.

2) Use `(>) a b` over `compare a b == GT` and allow inlining and specialization.
This mainly benefits types with a fast (>).

Note that this *may* break instances with a *malformed* Ord instance
where `a > b` is *not* equal to `compare a b == GT`.

CLC proposal: https://github.com/haskell/core-libraries-committee/issues/236

Fixes #24280

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Metric Decrease:
    MultiLayerModulesTH_Make
    T10421
    T13719
    T15164
    T18698a
    T18698b
    T1969
    T9872a
    T9961
    T18730
    WWRec
    T12425
    T15703
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fc2d6de1
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