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collections: merge unsafe_push_all_clone and push_all

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This commit is contained in:
Erick Tryzelaar 2014-07-07 09:45:00 -07:00
parent e2d107c397
commit b4984a490b
1 changed files with 14 additions and 29 deletions
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43
src/libcollections/vec.rs
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@ -197,14 +197,8 @@ impl<T: Clone> Vec<T> {
/// ```
#[inline]
pub fn from_slice(values: &[T]) -> Vec<T> {
let mut vector = Vec::with_capacity(values.len());
// Directly call `unsafe_push_all_clone` so we can skip a call to
// `reserve_addtional`.
unsafe {
unsafe_push_all_clone(&mut vector, values);
}
let mut vector = Vec::new();
vector.push_all(values);
vector
}
@ -248,8 +242,18 @@ impl<T: Clone> Vec<T> {
pub fn push_all(&mut self, other: &[T]) {
self.reserve_additional(other.len());
unsafe {
unsafe_push_all_clone(self, other)
for i in range(0, other.len()) {
let len = self.len();
// Unsafe code so this can be optimised to a memcpy (or something similarly
// fast) when T is Copy. LLVM is easily confused, so any extra operations
// during the loop can prevent this optimisation.
unsafe {
ptr::write(
self.as_mut_slice().unsafe_mut_ref(len),
other.unsafe_ref(i).clone());
self.set_len(len + 1);
}
}
}
@ -1550,25 +1554,6 @@ pub mod raw {
}
}
// Unsafe code so this can be optimised to a memcpy (or something similarly
// fast) when T is Copy. LLVM is easily confused, so any extra operations
// during the loop can prevent this optimisation.
//
// WARNING: You must preallocate space on the vector before you call this
// method.
#[inline(always)]
unsafe fn unsafe_push_all_clone<T: Clone>(dst: &mut Vec<T>, src: &[T]) {
let mut dst_len = dst.len();
for i in range(0, src.len()) {
ptr::write(
dst.as_mut_slice().unsafe_mut_ref(dst_len),
src.unsafe_ref(i).clone());
dst_len += 1;
dst.set_len(dst_len);
}
}
#[cfg(test)]
mod tests {
extern crate test;