[PATCH v4 4/6] xdiff/xdl_cleanup_records: make limits more clear

From

Ezekiel Newren via GitGitGadget <gitgitgadget@gmail.com>

Date

Mar 30, 2026, 17:00 UTC

Message-ID

<75fe3ea1250ab7dfa4e029f49f2ad353185afded.1774890003.git.gitgitgadget@gmail.com>

In-Reply-To

<pull.2156.v4.git.git.1774890003.gitgitgadget@gmail.com>

From: Ezekiel Newren <ezekielnewren@gmail.com>

Make the handling of per-file limits and the minimal-case clearer.
  * Use explicit per-file limit variables (mlim1, mlim2) and initialize
    them.
  * The additional condition `!need_min` is redudant now, remove it.
Best viewed with --color-words.

Signed-off-by: Ezekiel Newren <ezekielnewren@gmail.com>
---
 xdiff/xprepare.c | 19 ++++++++++++-------
 1 file changed, 12 insertions(+), 7 deletions(-)

diff --git a/xdiff/xprepare.c b/xdiff/xprepare.c
index 386668a92d..bd8baf214d 100644
--- a/xdiff/xprepare.c
+++ b/xdiff/xprepare.c
@@ -268,7 +268,7 @@ static bool xdl_clean_mmatch(uint8_t const *action, ptrdiff_t i, ptrdiff_t s, pt
  * might be potentially discarded if they appear in a run of discardable.
  */
 static int xdl_cleanup_records(xdlclassifier_t *cf, xdfile_t *xdf1, xdfile_t *xdf2) {
-	ptrdiff_t i, nm, mlim;
+	ptrdiff_t i, nm, mlim1, mlim2;
 	xdlclass_t *rcrec;
 	uint8_t *action1 = NULL, *action2 = NULL;
 	bool need_min = !!(cf->flags & XDF_NEED_MINIMAL);
@@ -287,25 +287,30 @@ static int xdl_cleanup_records(xdlclassifier_t *cf, xdfile_t *xdf1, xdfile_t *xd
 		goto cleanup;
 	}
 
+	if (need_min) {
+		/* i.e. infinity */
+		mlim1 = PTRDIFF_MAX;
+		mlim2 = PTRDIFF_MAX;
+	} else {
+		mlim1 = XDL_MIN(xdl_bogosqrt(xdf1->nrec), XDL_MAX_EQLIMIT);
+		mlim2 = XDL_MIN(xdl_bogosqrt(xdf2->nrec), XDL_MAX_EQLIMIT);
+	}
+
 	/*
 	 * Initialize temporary arrays with DISCARD, KEEP, or INVESTIGATE.
 	 */
-	if ((mlim = (long)xdl_bogosqrt((uint64_t)xdf1->nrec)) > XDL_MAX_EQLIMIT)
-		mlim = XDL_MAX_EQLIMIT;
 	for (i = xdf1->dstart; i <= xdf1->dend; i++) {
 		size_t mph1 = xdf1->recs[i].minimal_perfect_hash;
 		rcrec = cf->rcrecs[mph1];
 		nm = rcrec ? rcrec->len2 : 0;
-		action1[i] = (nm == 0) ? DISCARD: (nm >= mlim && !need_min) ? INVESTIGATE: KEEP;
+		action1[i] = (nm == 0) ? DISCARD: nm >= mlim1 ? INVESTIGATE: KEEP;
 	}
 
-	if ((mlim = (long)xdl_bogosqrt((uint64_t)xdf2->nrec)) > XDL_MAX_EQLIMIT)
-		mlim = XDL_MAX_EQLIMIT;
 	for (i = xdf2->dstart; i <= xdf2->dend; i++) {
 		size_t mph2 = xdf2->recs[i].minimal_perfect_hash;
 		rcrec = cf->rcrecs[mph2];
 		nm = rcrec ? rcrec->len1 : 0;
-		action2[i] = (nm == 0) ? DISCARD: (nm >= mlim && !need_min) ? INVESTIGATE: KEEP;
+		action2[i] = (nm == 0) ? DISCARD: nm >= mlim2 ? INVESTIGATE: KEEP;
 	}
 
 	/*

-- 
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