foster/denoland-deno
1
0
Fork 0
mirror of https://github.com/denoland/deno.git synced 2024-12-25 00:29:09 -05:00
Code Issues Packages 1 Wiki Activity

refactor(serde_v8): don't access backing store twice (#19382)

Browse source 
I did that change recently, did spot that we're calling 
`get_backing_store()` in succession and that API call
is not cheap.
This commit is contained in:
Bartek Iwańczuk 2023-06-06 16:02:16 +02:00
parent 61c65d671b
commit e70a1c2312
No known key found for this signature in database
GPG key ID: 0C6BCDDC3B3AD750
1 changed files with 8 additions and 19 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

27
serde_v8/magic/v8slice.rs
View file

@ -31,20 +31,6 @@ pub struct V8Slice {
unsafe impl Send for V8Slice {}
impl V8Slice {
pub fn from_buffer(
buffer: v8::Local<v8::ArrayBuffer>,
range: Range<usize>,
) -> Result<Self, v8::DataError> {
let store = buffer.get_backing_store();
if store.is_shared() {
return Err(v8::DataError::BadType {
actual: "shared ArrayBufferView",
expected: "non-shared ArrayBufferView",
});
}
Ok(Self { store, range })
}
fn as_slice(&self) -> &[u8] {
// SAFETY: v8::SharedRef<v8::BackingStore> is similar to Arc<[u8]>,
// it points to a fixed continuous slice of bytes on the heap.
@ -92,12 +78,15 @@ impl FromV8 for V8Slice {
value: v8::Local<v8::Value>,
) -> Result<Self, crate::Error> {
match to_ranged_buffer(scope, value) {
Ok((b, r)) => {
if b.get_backing_store().is_resizable_by_user_javascript() {
return Err(crate::Error::ResizableBackingStoreNotSupported);
Ok((b, range)) => {
let store = b.get_backing_store();
if store.is_resizable_by_user_javascript() {
Err(crate::Error::ResizableBackingStoreNotSupported)
} else if store.is_shared() {
Err(crate::Error::ExpectedBuffer(value_to_type_str(value)))
} else {
Ok(V8Slice { store, range })
}
Self::from_buffer(b, r)
.map_err(|_| crate::Error::ExpectedBuffer(value_to_type_str(value)))
}
Err(_) => Err(crate::Error::ExpectedBuffer(value_to_type_str(value))),
}