tor-browser

commit 3c213707b73adac686fd208ff1f109d7a39bea2e
parent 7252cb0aa54684bb7dde137be692a1483027aa78
Author: Jonathan Kew <jkew@mozilla.com>
Date:   Mon, 10 Nov 2025 22:10:58 +0000

Bug 1999164 - If unicode-range is simply 0..10FFFF, don't bother to create a gfxCharacterMap for it as nothing will be masked. r=layout-reviewers,firefox-style-system-reviewers,emilio

This virtually eliminates GetUnicodeRangeAsCharacterMap from the profile with the testcase here.

Differential Revision: https://phabricator.services.mozilla.com/D272045

Diffstat:
M
layout/style/FontFaceImpl.cpp
 | 
5
+++++

1 file changed, 5 insertions(+), 0 deletions(-)
diff --git a/layout/style/FontFaceImpl.cpp b/layout/style/FontFaceImpl.cpp
@@ -609,6 +609,11 @@ static already_AddRefed<gfxCharacterMap> ComputeCharacterMap(
   if (ranges.IsEmpty()) {
     return nullptr;
   }
+  // A single range covering the entire Unicode code space is equivalent to
+  // having no range at all.
+  if (ranges.Length() == 1 && ranges[0] == StyleUnicodeRange{0, 0x10ffff}) {
+    return nullptr;
+  }
   auto charMap = MakeRefPtr<gfxCharacterMap>(256);
   for (auto& range : ranges) {
     charMap->SetRange(range.start, range.end);