/// Provenance in this map only applies to the given single byte.
/// This map is disjoint from the previous. It will always be empty when
/// `Prov::OFFSET_IS_ADDR` is false.
- bytes: SortedMap<Size, Prov>,
+ bytes: Option<Box<SortedMap<Size, Prov>>>,
}
impl<Prov> ProvenanceMap<Prov> {
pub fn new() -> Self {
- ProvenanceMap { ptrs: SortedMap::new(), bytes: SortedMap::new() }
+ ProvenanceMap { ptrs: SortedMap::new(), bytes: None }
}
/// The caller must guarantee that the given provenance list is already sorted
/// by address and contain no duplicates.
pub fn from_presorted_ptrs(r: Vec<(Size, Prov)>) -> Self {
- ProvenanceMap { ptrs: SortedMap::from_presorted_elements(r), bytes: SortedMap::new() }
+ ProvenanceMap { ptrs: SortedMap::from_presorted_elements(r), bytes: None }
}
}
/// Only exposed with `AllocId` provenance, since it panics if there is bytewise provenance.
#[inline]
pub fn ptrs(&self) -> &SortedMap<Size, AllocId> {
- debug_assert!(self.bytes.is_empty()); // `AllocId::OFFSET_IS_ADDR` is false so this cannot fail
+ debug_assert!(self.bytes.is_none()); // `AllocId::OFFSET_IS_ADDR` is false so this cannot fail
&self.ptrs
}
}
/// Returns all byte-wise provenance in the given range.
fn range_get_bytes(&self, range: AllocRange) -> &[(Size, Prov)] {
- self.bytes.range(range.start..range.end())
+ if let Some(bytes) = self.bytes.as_ref() {
+ bytes.range(range.start..range.end())
+ } else {
+ &[]
+ }
}
/// Get the provenance of a single byte.
debug_assert!(prov.len() <= 1);
if let Some(entry) = prov.first() {
// If it overlaps with this byte, it is on this byte.
- debug_assert!(self.bytes.get(&offset).is_none());
+ debug_assert!(self.bytes.as_ref().map_or(true, |b| b.get(&offset).is_none()));
Some(entry.1)
} else {
// Look up per-byte provenance.
- self.bytes.get(&offset).copied()
+ self.bytes.as_ref().and_then(|b| b.get(&offset).copied())
}
}
/// Yields all the provenances stored in this map.
pub fn provenances(&self) -> impl Iterator<Item = Prov> + '_ {
- self.ptrs.values().chain(self.bytes.values()).copied()
+ let bytes = self.bytes.iter().flat_map(|b| b.values());
+ self.ptrs.values().chain(bytes).copied()
}
pub fn insert_ptr(&mut self, offset: Size, prov: Prov, cx: &impl HasDataLayout) {
let end = range.end();
// Clear the bytewise part -- this is easy.
if Prov::OFFSET_IS_ADDR {
- self.bytes.remove_range(start..end);
+ if let Some(bytes) = self.bytes.as_mut() {
+ bytes.remove_range(start..end);
+ }
} else {
- debug_assert!(self.bytes.is_empty());
+ debug_assert!(self.bytes.is_none());
}
// For the ptr-sized part, find the first (inclusive) and last (exclusive) byte of
}
// Insert the remaining part in the bytewise provenance.
let prov = self.ptrs[&first];
+ let bytes = self.bytes.get_or_insert_with(Box::default);
for offset in first..start {
- self.bytes.insert(offset, prov);
+ bytes.insert(offset, prov);
}
}
if last > end {
}
// Insert the remaining part in the bytewise provenance.
let prov = self.ptrs[&begin_of_last];
+ let bytes = self.bytes.get_or_insert_with(Box::default);
for offset in end..last {
- self.bytes.insert(offset, prov);
+ bytes.insert(offset, prov);
}
}
///
/// Offsets are already adjusted to the destination allocation.
pub struct ProvenanceCopy<Prov> {
- dest_ptrs: Vec<(Size, Prov)>,
- dest_bytes: Vec<(Size, Prov)>,
+ dest_ptrs: Option<Box<[(Size, Prov)]>>,
+ dest_bytes: Option<Box<[(Size, Prov)]>>,
}
impl<Prov: Provenance> ProvenanceMap<Prov> {
// Get the provenances that are entirely within this range.
// (Different from `range_get_ptrs` which asks if they overlap the range.)
// Only makes sense if we are copying at least one pointer worth of bytes.
- let mut dest_ptrs = Vec::new();
+ let mut dest_ptrs_box = None;
if src.size >= ptr_size {
let adjusted_end = Size::from_bytes(src.end().bytes() - (ptr_size.bytes() - 1));
let ptrs = self.ptrs.range(src.start..adjusted_end);
- dest_ptrs.reserve_exact(ptrs.len() * (count as usize));
// If `count` is large, this is rather wasteful -- we are allocating a big array here, which
// is mostly filled with redundant information since it's just N copies of the same `Prov`s
// at slightly adjusted offsets. The reason we do this is so that in `mark_provenance_range`
// we can use `insert_presorted`. That wouldn't work with an `Iterator` that just produces
// the right sequence of provenance for all N copies.
// Basically, this large array would have to be created anyway in the target allocation.
+ let mut dest_ptrs = Vec::with_capacity(ptrs.len() * (count as usize));
for i in 0..count {
dest_ptrs
.extend(ptrs.iter().map(|&(offset, reloc)| (shift_offset(i, offset), reloc)));
}
+ debug_assert_eq!(dest_ptrs.len(), dest_ptrs.capacity());
+ dest_ptrs_box = Some(dest_ptrs.into_boxed_slice());
};
// # Byte-sized provenances
- let mut bytes = Vec::new();
- // First, if there is a part of a pointer at the start, add that.
- if let Some(entry) = self.range_get_ptrs(alloc_range(src.start, Size::ZERO), cx).first() {
- if !Prov::OFFSET_IS_ADDR {
- // We can't split up the provenance into less than a pointer.
+ // This includes the existing bytewise provenance in the range, and ptr provenance
+ // that overlaps with the begin/end of the range.
+ let mut dest_bytes_box = None;
+ let begin_overlap = self.range_get_ptrs(alloc_range(src.start, Size::ZERO), cx).first();
+ let end_overlap = self.range_get_ptrs(alloc_range(src.end(), Size::ZERO), cx).first();
+ if !Prov::OFFSET_IS_ADDR {
+ // There can't be any bytewise provenance, and we cannot split up the begin/end overlap.
+ if let Some(entry) = begin_overlap {
return Err(AllocError::PartialPointerCopy(entry.0));
}
- trace!("start overlapping entry: {entry:?}");
- // For really small copies, make sure we don't run off the end of the `src` range.
- let entry_end = cmp::min(entry.0 + ptr_size, src.end());
- for offset in src.start..entry_end {
- bytes.push((offset, entry.1));
- }
- } else {
- trace!("no start overlapping entry");
- }
- // Then the main part, bytewise provenance from `self.bytes`.
- if Prov::OFFSET_IS_ADDR {
- bytes.extend(self.bytes.range(src.start..src.end()));
- } else {
- debug_assert!(self.bytes.is_empty());
- }
- // And finally possibly parts of a pointer at the end.
- if let Some(entry) = self.range_get_ptrs(alloc_range(src.end(), Size::ZERO), cx).first() {
- if !Prov::OFFSET_IS_ADDR {
- // We can't split up the provenance into less than a pointer.
+ if let Some(entry) = end_overlap {
return Err(AllocError::PartialPointerCopy(entry.0));
}
- trace!("end overlapping entry: {entry:?}");
- // For really small copies, make sure we don't start before `src` does.
- let entry_start = cmp::max(entry.0, src.start);
- for offset in entry_start..src.end() {
- if bytes.last().map_or(true, |bytes_entry| bytes_entry.0 < offset) {
- // The last entry, if it exists, has a lower offset than us.
+ debug_assert!(self.bytes.is_none());
+ } else {
+ let mut bytes = Vec::new();
+ // First, if there is a part of a pointer at the start, add that.
+ if let Some(entry) = begin_overlap {
+ trace!("start overlapping entry: {entry:?}");
+ // For really small copies, make sure we don't run off the end of the `src` range.
+ let entry_end = cmp::min(entry.0 + ptr_size, src.end());
+ for offset in src.start..entry_end {
bytes.push((offset, entry.1));
- } else {
- // There already is an entry for this offset in there! This can happen when the
- // start and end range checks actually end up hitting the same pointer, so we
- // already added this in the "pointer at the start" part above.
- assert!(entry.0 <= src.start);
}
+ } else {
+ trace!("no start overlapping entry");
}
- } else {
- trace!("no end overlapping entry");
- }
- trace!("byte provenances: {bytes:?}");
+ // Then the main part, bytewise provenance from `self.bytes`.
+ if let Some(all_bytes) = self.bytes.as_ref() {
+ bytes.extend(all_bytes.range(src.start..src.end()));
+ }
+ // And finally possibly parts of a pointer at the end.
+ if let Some(entry) = end_overlap {
+ trace!("end overlapping entry: {entry:?}");
+ // For really small copies, make sure we don't start before `src` does.
+ let entry_start = cmp::max(entry.0, src.start);
+ for offset in entry_start..src.end() {
+ if bytes.last().map_or(true, |bytes_entry| bytes_entry.0 < offset) {
+ // The last entry, if it exists, has a lower offset than us.
+ bytes.push((offset, entry.1));
+ } else {
+ // There already is an entry for this offset in there! This can happen when the
+ // start and end range checks actually end up hitting the same pointer, so we
+ // already added this in the "pointer at the start" part above.
+ assert!(entry.0 <= src.start);
+ }
+ }
+ } else {
+ trace!("no end overlapping entry");
+ }
+ trace!("byte provenances: {bytes:?}");
- // And again a buffer for the new list on the target side.
- let mut dest_bytes = Vec::new();
- if Prov::OFFSET_IS_ADDR {
- dest_bytes.reserve_exact(bytes.len() * (count as usize));
+ // And again a buffer for the new list on the target side.
+ let mut dest_bytes = Vec::with_capacity(bytes.len() * (count as usize));
for i in 0..count {
dest_bytes
.extend(bytes.iter().map(|&(offset, reloc)| (shift_offset(i, offset), reloc)));
}
- } else {
- // There can't be any bytewise provenance when OFFSET_IS_ADDR is false.
- debug_assert!(bytes.is_empty());
+ debug_assert_eq!(dest_bytes.len(), dest_bytes.capacity());
+ dest_bytes_box = Some(dest_bytes.into_boxed_slice());
}
- Ok(ProvenanceCopy { dest_ptrs, dest_bytes })
+ Ok(ProvenanceCopy { dest_ptrs: dest_ptrs_box, dest_bytes: dest_bytes_box })
}
/// Applies a provenance copy.
/// The affected range, as defined in the parameters to `prepare_copy` is expected
/// to be clear of provenance.
pub fn apply_copy(&mut self, copy: ProvenanceCopy<Prov>) {
- self.ptrs.insert_presorted(copy.dest_ptrs);
+ if let Some(dest_ptrs) = copy.dest_ptrs {
+ self.ptrs.insert_presorted(dest_ptrs.into());
+ }
if Prov::OFFSET_IS_ADDR {
- self.bytes.insert_presorted(copy.dest_bytes);
+ if let Some(dest_bytes) = copy.dest_bytes && !dest_bytes.is_empty() {
+ self.bytes.get_or_insert_with(Box::default).insert_presorted(dest_bytes.into());
+ }
} else {
- debug_assert!(copy.dest_bytes.is_empty());
+ debug_assert!(copy.dest_bytes.is_none());
}
}
}
projects / rust.git / commitdiff