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Date:   Tue, 14 Dec 2021 08:39:36 -0500
From:   Jeff King <peff@peff.net>
To:     =?utf-8?B?w4Z2YXIgQXJuZmrDtnLDsA==?= Bjarmason <avarab@gmail.com>
Cc:     git@vger.kernel.org, Junio C Hamano <gitster@pobox.com>,
        Johannes Schindelin <Johannes.Schindelin@gmx.de>,
        Erik Faye-Lund <kusmabite@gmail.com>,
        Jonathan Nieder <jrnieder@gmail.com>
Subject: Re: [RFC PATCH v2 2/5] linear-assignment.c: split up
 compute_assignment() function
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References: <RFC-cover-00.10-00000000000-20211209T191653Z-avarab@gmail.com>
 <RFC-cover-v2-0.5-00000000000-20211210T122901Z-avarab@gmail.com>
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On Fri, Dec 10, 2021 at 01:30:39PM +0100, Ævar Arnfjörð Bjarmason wrote:

> Split up the the long compute_assignment() function to make it easier
> to reason about, particularly when it comes to what variables are used
> later, and which aren't.

OK, this refactor seems reasonable. I don't know enough about the
linear-assignment algorithm to know whether the names you've picked are
meaningful.

> +void compute_assignment(int column_count, int row_count,
> +			int *cost,
> +			int *column2row, int *row2column)
> +{
> +	int *v;
> +	int *free_row, free_count = 0, saved_free_count;
> +
> +	assert(column_count > 1);
> +	memset(column2row, -1, sizeof(int) * column_count);
> +	memset(row2column, -1, sizeof(int) * row_count);
> +	ALLOC_ARRAY(v, column_count);

So this is the code where we would have kept the column_count check and
zero'd column2row and row2column, had we not moved it in the previous
commit. I actually think it would fit fine here in the refactored
compute_assignment() if you had left it.

-Peff