foster/denoland-rusty-v8
0
0
Fork 0
mirror of https://github.com/denoland/rusty_v8.git synced 2024-12-25 08:39:15 -05:00
Code Issues Activity

fix: don't allocate for zero-length strings (#1309)

Browse source
This commit is contained in:
Matt Mastracci 2023-09-01 08:54:52 -04:00 committed by GitHub
parent aa203e032c
commit 987d520221
No known key found for this signature in database
GPG key ID: 4AEE18F83AFDEB23
1 changed files with 14 additions and 2 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

16
src/string.rs
View file

@ -552,9 +552,15 @@ impl String {
&self,
scope: &mut Isolate,
) -> std::string::String {
let len_utf8 = self.utf8_length(scope);
let len_utf16 = self.length();
// No need to allocate or do any work for zero-length strings
if len_utf16 == 0 {
return std::string::String::new();
}
let len_utf8 = self.utf8_length(scope);
// If len_utf8 == len_utf16 and the string is one-byte, we can take the fast memcpy path. This is true iff the
// string is 100% 7-bit ASCII.
if self.is_onebyte() && len_utf8 == len_utf16 {
@ -612,9 +618,15 @@ impl String {
scope: &mut Isolate,
buffer: &'a mut [MaybeUninit<u8>; N],
) -> Cow<'a, str> {
let len_utf16 = self.length();
// No need to allocate or do any work for zero-length strings
if len_utf16 == 0 {
return "".into();
}
// TODO(mmastrac): Ideally we should be able to access the string's internal representation
let len_utf8 = self.utf8_length(scope);
let len_utf16 = self.length();
// If len_utf8 == len_utf16 and the string is one-byte, we can take the fast memcpy path. This is true iff the
// string is 100% 7-bit ASCII.