From 6187aa0b1bfcba7e5d956e05685ad1de42666221 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Daniel=20Ekl=C3=B6f?= <daniel@ekloef.se>
Date: Tue, 15 Jun 2021 08:44:52 +0200
Subject: [PATCH] term: lower maximum number of characters in a compose chain
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Before the grapheme cluster segmentation work, we limited the number
of combining characters to base+5. I.e. 6 in total.

For a while now, we’ve had it bumped all the way up to 20. This was
the reason the unicode-random benchmark ran so much slower (i.e. cache
contention).

Looking at emoji’s, there are a couple that need 6 code points,
and *three* that needs 7.

Now, with the limit at 7 chars, and the new ‘width’ member, the
composed struct is 8 bytes larger than before.
---
 terminal.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/terminal.h b/terminal.h
index 83406f41..307e2b0b 100644
--- a/terminal.h
+++ b/terminal.h
@@ -85,7 +85,7 @@ struct damage {
 };
 
 struct composed {
-    wchar_t chars[20];
+    wchar_t chars[7];
     uint8_t count;
     int width;
 };