Document missing unsafe blocks · rust-lang/rust@5eff264 (original) (raw)
`@@ -21,6 +21,9 @@ struct InsertionHole {
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`impl Drop for InsertionHole {
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`fn drop(&mut self) {
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// SAFETY: This is a helper class. Please refer to its usage for correctness. Namely, one
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// must be sure that src and dst does not overlap as required by
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// ptr::copy_nonoverlapping and are both valid for writes.
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`unsafe {
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` ptr::copy_nonoverlapping(self.src, self.dest, 1);
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`}
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`{
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`debug_assert!(v.len() >= 2);
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``
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// SAFETY: caller must ensure v is at least len 2.
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`unsafe {
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`if is_less(v.get_unchecked(1), v.get_unchecked(0)) {
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`let arr_ptr = v.as_mut_ptr();
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`@@ -153,7 +157,8 @@ where
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`// Shift each element of the unsorted region v[i..] as far left as is needed to make v sorted.
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`for i in offset..len {
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`` // SAFETY: we tested that offset must be at least 1, so this loop is only entered if len
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// >= 2.
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// >= 2. The range is exclusive and we know i must be at least 1 so this slice has at
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// >least len 2.
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`unsafe {
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`insert_tail(&mut v[..=i], is_less);
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`}
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`@@ -176,9 +181,10 @@ where
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`// Shift each element of the unsorted region v[..i] as far left as is needed to make v sorted.
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`for i in (0..offset).rev() {
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``
`-
// We ensured that the slice length is always at least 2 long.
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// We know that start_found will be at least one less than end,
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// and the range is exclusive. Which gives us i always <= (end - 2).
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// SAFETY: we tested that offset must be at least 1, so this loop is only entered if len
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// >= 2.We ensured that the slice length is always at least 2 long. We know that start_found
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// will be at least one less than end, and the range is exclusive. Which gives us i always
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// <= (end - 2).
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`unsafe {
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`insert_head(&mut v[i..len], is_less);
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`}
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`@@ -1222,6 +1228,8 @@ pub fn merge_sort<T, CmpF, ElemAllocF, ElemDeallocF, RunAllocF, RunDeallocF>(
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`let left = runs[r];
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`let right = runs[r + 1];
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`let merge_slice = &mut v[left.start..right.start + right.len];
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// SAFETY: buf_ptr must hold enough capacity for the shorter of the two sides, and
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// neither side may be on length 0.
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`unsafe {
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`merge(merge_slice, left.len, buf_ptr, is_less);
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`}
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