encounter
/
dawn-cmake
mirror of https://github.com/encounter/dawn-cmake.git
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

Short circuit IsXIDStart check. 

Our common case is ASCII characters but, because those come at the start
of the XID Start range they'll end up being checked _last_ as we binary
search through the range. This means we're getting the worst case
behaviour for our common character.

This CL adds a quick check for [a-zA-Z] at the start of IsXIDStart to
quickly determine if we're an ascii character.

Change-Id: Iae733b0e8a64c855764cf58c0563a407e6a81f7d
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/97068
Kokoro: Kokoro <noreply+kokoro@google.com>
Commit-Queue: Dan Sinclair <dsinclair@chromium.org>
Reviewed-by: Ben Clayton <bclayton@google.com>
Commit-Queue: Ben Clayton <bclayton@google.com>
This commit is contained in:
dan sinclair 2022-07-24 19:06:07 +00:00 committed by Dawn LUCI CQ
parent afa7eff921
commit 3f9cc84d0a
1 changed files with 5 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

5
src/tint/text/unicode.cc
View File

@ -306,6 +306,11 @@ constexpr size_t kNumXIDContinueRanges = sizeof(kXIDContinueRanges) / sizeof(kXI
} // namespace } // namespace
bool CodePoint::IsXIDStart() const { bool CodePoint::IsXIDStart() const {
// Short circuit ascii. It will end up being at the end of the binary search
// but is our, currently, common case.
if ((value >= 'a' && value <= 'z') || (value >= 'A' && value <= 'Z')) {
return true;
}
return std::binary_search(kXIDStartRanges, kXIDStartRanges + kNumXIDStartRanges, *this); return std::binary_search(kXIDStartRanges, kXIDStartRanges + kNumXIDStartRanges, *this);
} }