diff options
Diffstat (limited to 'compiler/rustc_middle')
5 files changed, 129 insertions, 116 deletions
diff --git a/compiler/rustc_middle/src/mir/interpret/allocation.rs b/compiler/rustc_middle/src/mir/interpret/allocation.rs index 27ead514531..2ea92a39d48 100644 --- a/compiler/rustc_middle/src/mir/interpret/allocation.rs +++ b/compiler/rustc_middle/src/mir/interpret/allocation.rs @@ -306,8 +306,6 @@ pub enum AllocError { ScalarSizeMismatch(ScalarSizeMismatch), /// Encountered a pointer where we needed raw bytes. ReadPointerAsInt(Option<BadBytesAccess>), - /// Partially overwriting a pointer. - OverwritePartialPointer(Size), /// Partially copying a pointer. ReadPartialPointer(Size), /// Using uninitialized data where it is not allowed. @@ -331,9 +329,6 @@ impl AllocError { ReadPointerAsInt(info) => InterpErrorKind::Unsupported( UnsupportedOpInfo::ReadPointerAsInt(info.map(|b| (alloc_id, b))), ), - OverwritePartialPointer(offset) => InterpErrorKind::Unsupported( - UnsupportedOpInfo::OverwritePartialPointer(Pointer::new(alloc_id, offset)), - ), ReadPartialPointer(offset) => InterpErrorKind::Unsupported( UnsupportedOpInfo::ReadPartialPointer(Pointer::new(alloc_id, offset)), ), @@ -633,11 +628,11 @@ impl<Prov: Provenance, Extra, Bytes: AllocBytes> Allocation<Prov, Extra, Bytes> &mut self, cx: &impl HasDataLayout, range: AllocRange, - ) -> AllocResult<&mut [u8]> { + ) -> &mut [u8] { self.mark_init(range, true); - self.provenance.clear(range, cx)?; + self.provenance.clear(range, cx); - Ok(&mut self.bytes[range.start.bytes_usize()..range.end().bytes_usize()]) + &mut self.bytes[range.start.bytes_usize()..range.end().bytes_usize()] } /// A raw pointer variant of `get_bytes_unchecked_for_overwrite` that avoids invalidating existing immutable aliases @@ -646,15 +641,15 @@ impl<Prov: Provenance, Extra, Bytes: AllocBytes> Allocation<Prov, Extra, Bytes> &mut self, cx: &impl HasDataLayout, range: AllocRange, - ) -> AllocResult<*mut [u8]> { + ) -> *mut [u8] { self.mark_init(range, true); - self.provenance.clear(range, cx)?; + self.provenance.clear(range, cx); assert!(range.end().bytes_usize() <= self.bytes.len()); // need to do our own bounds-check // Crucially, we go via `AllocBytes::as_mut_ptr`, not `AllocBytes::deref_mut`. let begin_ptr = self.bytes.as_mut_ptr().wrapping_add(range.start.bytes_usize()); let len = range.end().bytes_usize() - range.start.bytes_usize(); - Ok(ptr::slice_from_raw_parts_mut(begin_ptr, len)) + ptr::slice_from_raw_parts_mut(begin_ptr, len) } /// This gives direct mutable access to the entire buffer, just exposing their internal state @@ -723,26 +718,45 @@ impl<Prov: Provenance, Extra, Bytes: AllocBytes> Allocation<Prov, Extra, Bytes> let ptr = Pointer::new(prov, Size::from_bytes(bits)); return Ok(Scalar::from_pointer(ptr, cx)); } - - // If we can work on pointers byte-wise, join the byte-wise provenances. - if Prov::OFFSET_IS_ADDR { - let mut prov = self.provenance.get(range.start, cx); + // The other easy case is total absence of provenance. + if self.provenance.range_empty(range, cx) { + return Ok(Scalar::from_uint(bits, range.size)); + } + // If we get here, we have to check per-byte provenance, and join them together. + let prov = 'prov: { + // Initialize with first fragment. Must have index 0. + let Some((mut joint_prov, 0)) = self.provenance.get_byte(range.start, cx) else { + break 'prov None; + }; + // Update with the remaining fragments. for offset in Size::from_bytes(1)..range.size { - let this_prov = self.provenance.get(range.start + offset, cx); - prov = Prov::join(prov, this_prov); + // Ensure there is provenance here and it has the right index. + let Some((frag_prov, frag_idx)) = + self.provenance.get_byte(range.start + offset, cx) + else { + break 'prov None; + }; + // Wildcard provenance is allowed to come with any index (this is needed + // for Miri's native-lib mode to work). + if u64::from(frag_idx) != offset.bytes() && Some(frag_prov) != Prov::WILDCARD { + break 'prov None; + } + // Merge this byte's provenance with the previous ones. + joint_prov = match Prov::join(joint_prov, frag_prov) { + Some(prov) => prov, + None => break 'prov None, + }; } - // Now use this provenance. - let ptr = Pointer::new(prov, Size::from_bytes(bits)); - return Ok(Scalar::from_maybe_pointer(ptr, cx)); - } else { - // Without OFFSET_IS_ADDR, the only remaining case we can handle is total absence of - // provenance. - if self.provenance.range_empty(range, cx) { - return Ok(Scalar::from_uint(bits, range.size)); - } - // Else we have mixed provenance, that doesn't work. + break 'prov Some(joint_prov); + }; + if prov.is_none() && !Prov::OFFSET_IS_ADDR { + // There are some bytes with provenance here but overall the provenance does not add up. + // We need `OFFSET_IS_ADDR` to fall back to no-provenance here; without that option, we must error. return Err(AllocError::ReadPartialPointer(range.start)); } + // We can use this provenance. + let ptr = Pointer::new(prov, Size::from_bytes(bits)); + return Ok(Scalar::from_maybe_pointer(ptr, cx)); } else { // We are *not* reading a pointer. // If we can just ignore provenance or there is none, that's easy. @@ -782,7 +796,7 @@ impl<Prov: Provenance, Extra, Bytes: AllocBytes> Allocation<Prov, Extra, Bytes> let endian = cx.data_layout().endian; // Yes we do overwrite all the bytes in `dst`. - let dst = self.get_bytes_unchecked_for_overwrite(cx, range)?; + let dst = self.get_bytes_unchecked_for_overwrite(cx, range); write_target_uint(endian, dst, bytes).unwrap(); // See if we have to also store some provenance. @@ -795,10 +809,9 @@ impl<Prov: Provenance, Extra, Bytes: AllocBytes> Allocation<Prov, Extra, Bytes> } /// Write "uninit" to the given memory range. - pub fn write_uninit(&mut self, cx: &impl HasDataLayout, range: AllocRange) -> AllocResult { + pub fn write_uninit(&mut self, cx: &impl HasDataLayout, range: AllocRange) { self.mark_init(range, false); - self.provenance.clear(range, cx)?; - Ok(()) + self.provenance.clear(range, cx); } /// Mark all bytes in the given range as initialised and reset the provenance @@ -817,9 +830,12 @@ impl<Prov: Provenance, Extra, Bytes: AllocBytes> Allocation<Prov, Extra, Bytes> } /// Remove all provenance in the given memory range. - pub fn clear_provenance(&mut self, cx: &impl HasDataLayout, range: AllocRange) -> AllocResult { - self.provenance.clear(range, cx)?; - return Ok(()); + pub fn clear_provenance(&mut self, cx: &impl HasDataLayout, range: AllocRange) { + self.provenance.clear(range, cx); + } + + pub fn provenance_merge_bytes(&mut self, cx: &impl HasDataLayout) -> bool { + self.provenance.merge_bytes(cx) } /// Applies a previously prepared provenance copy. diff --git a/compiler/rustc_middle/src/mir/interpret/allocation/provenance_map.rs b/compiler/rustc_middle/src/mir/interpret/allocation/provenance_map.rs index 119d4be64e6..ea8596ea286 100644 --- a/compiler/rustc_middle/src/mir/interpret/allocation/provenance_map.rs +++ b/compiler/rustc_middle/src/mir/interpret/allocation/provenance_map.rs @@ -10,7 +10,7 @@ use rustc_macros::HashStable; use rustc_serialize::{Decodable, Decoder, Encodable, Encoder}; use tracing::trace; -use super::{AllocError, AllocRange, AllocResult, CtfeProvenance, Provenance, alloc_range}; +use super::{AllocRange, CtfeProvenance, Provenance, alloc_range}; /// Stores the provenance information of pointers stored in memory. #[derive(Clone, PartialEq, Eq, Hash, Debug)] @@ -19,25 +19,25 @@ pub struct ProvenanceMap<Prov = CtfeProvenance> { /// `Provenance` in this map applies from the given offset for an entire pointer-size worth of /// bytes. Two entries in this map are always at least a pointer size apart. ptrs: SortedMap<Size, Prov>, - /// 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: Option<Box<SortedMap<Size, Prov>>>, + /// This stores byte-sized provenance fragments. + /// The `u8` indicates the position of this byte inside its original pointer. + /// If the bytes are re-assembled in their original order, the pointer can be used again. + /// Wildcard provenance is allowed to have index 0 everywhere. + bytes: Option<Box<SortedMap<Size, (Prov, u8)>>>, } // These impls are generic over `Prov` since `CtfeProvenance` is only decodable/encodable // for some particular `D`/`S`. impl<D: Decoder, Prov: Provenance + Decodable<D>> Decodable<D> for ProvenanceMap<Prov> { fn decode(d: &mut D) -> Self { - assert!(!Prov::OFFSET_IS_ADDR); // only `CtfeProvenance` is ever serialized + // `bytes` is not in the serialized format Self { ptrs: Decodable::decode(d), bytes: None } } } impl<S: Encoder, Prov: Provenance + Encodable<S>> Encodable<S> for ProvenanceMap<Prov> { fn encode(&self, s: &mut S) { let Self { ptrs, bytes } = self; - assert!(!Prov::OFFSET_IS_ADDR); // only `CtfeProvenance` is ever serialized - debug_assert!(bytes.is_none()); // without `OFFSET_IS_ADDR`, this is always empty + assert!(bytes.is_none()); // interning refuses allocations with pointer fragments ptrs.encode(s) } } @@ -58,10 +58,10 @@ impl ProvenanceMap { /// Give access to the ptr-sized provenances (which can also be thought of as relocations, and /// indeed that is how codegen treats them). /// - /// Only exposed with `CtfeProvenance` provenance, since it panics if there is bytewise provenance. + /// Only use on interned allocations, as other allocations may have per-byte provenance! #[inline] pub fn ptrs(&self) -> &SortedMap<Size, CtfeProvenance> { - debug_assert!(self.bytes.is_none()); // `CtfeProvenance::OFFSET_IS_ADDR` is false so this cannot fail + assert!(self.bytes.is_none(), "`ptrs()` called on non-interned allocation"); &self.ptrs } } @@ -88,12 +88,12 @@ impl<Prov: Provenance> ProvenanceMap<Prov> { } /// `pm.range_ptrs_is_empty(r, cx)` == `pm.range_ptrs_get(r, cx).is_empty()`, but is faster. - pub(super) fn range_ptrs_is_empty(&self, range: AllocRange, cx: &impl HasDataLayout) -> bool { + fn range_ptrs_is_empty(&self, range: AllocRange, cx: &impl HasDataLayout) -> bool { self.ptrs.range_is_empty(Self::adjusted_range_ptrs(range, cx)) } /// Returns all byte-wise provenance in the given range. - fn range_bytes_get(&self, range: AllocRange) -> &[(Size, Prov)] { + fn range_bytes_get(&self, range: AllocRange) -> &[(Size, (Prov, u8))] { if let Some(bytes) = self.bytes.as_ref() { bytes.range(range.start..range.end()) } else { @@ -107,19 +107,47 @@ impl<Prov: Provenance> ProvenanceMap<Prov> { } /// Get the provenance of a single byte. - pub fn get(&self, offset: Size, cx: &impl HasDataLayout) -> Option<Prov> { + pub fn get_byte(&self, offset: Size, cx: &impl HasDataLayout) -> Option<(Prov, u8)> { let prov = self.range_ptrs_get(alloc_range(offset, Size::from_bytes(1)), cx); 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.as_ref().is_none_or(|b| !b.contains_key(&offset))); - Some(entry.1) + Some((entry.1, (offset - entry.0).bytes() as u8)) } else { // Look up per-byte provenance. self.bytes.as_ref().and_then(|b| b.get(&offset).copied()) } } + /// Attempt to merge per-byte provenance back into ptr chunks, if the right fragments + /// sit next to each other. Return `false` is that is not possible due to partial pointers. + pub fn merge_bytes(&mut self, cx: &impl HasDataLayout) -> bool { + let Some(bytes) = self.bytes.as_deref_mut() else { + return true; + }; + let ptr_size = cx.data_layout().pointer_size(); + while let Some((offset, (prov, _))) = bytes.iter().next().copied() { + // Check if this fragment starts a pointer. + let range = offset..offset + ptr_size; + let frags = bytes.range(range.clone()); + if frags.len() != ptr_size.bytes_usize() { + return false; + } + for (idx, (_offset, (frag_prov, frag_idx))) in frags.iter().copied().enumerate() { + if frag_prov != prov || frag_idx != idx as u8 { + return false; + } + } + // Looks like a pointer! Move it over to the ptr provenance map. + bytes.remove_range(range); + self.ptrs.insert(offset, prov); + } + // We managed to convert everything into whole pointers. + self.bytes = None; + true + } + /// Check if there is ptr-sized provenance at the given index. /// Does not mean anything for bytewise provenance! But can be useful as an optimization. pub fn get_ptr(&self, offset: Size) -> Option<Prov> { @@ -137,7 +165,7 @@ impl<Prov: Provenance> ProvenanceMap<Prov> { /// Yields all the provenances stored in this map. pub fn provenances(&self) -> impl Iterator<Item = Prov> { - let bytes = self.bytes.iter().flat_map(|b| b.values()); + let bytes = self.bytes.iter().flat_map(|b| b.values().map(|(p, _i)| p)); self.ptrs.values().chain(bytes).copied() } @@ -148,16 +176,12 @@ impl<Prov: Provenance> ProvenanceMap<Prov> { /// Removes all provenance inside the given range. /// If there is provenance overlapping with the edges, might result in an error. - pub fn clear(&mut self, range: AllocRange, cx: &impl HasDataLayout) -> AllocResult { + pub fn clear(&mut self, range: AllocRange, cx: &impl HasDataLayout) { let start = range.start; let end = range.end(); // Clear the bytewise part -- this is easy. - if Prov::OFFSET_IS_ADDR { - if let Some(bytes) = self.bytes.as_mut() { - bytes.remove_range(start..end); - } - } else { - debug_assert!(self.bytes.is_none()); + if let Some(bytes) = self.bytes.as_mut() { + bytes.remove_range(start..end); } let pointer_size = cx.data_layout().pointer_size(); @@ -168,7 +192,7 @@ impl<Prov: Provenance> ProvenanceMap<Prov> { // Find all provenance overlapping the given range. if self.range_ptrs_is_empty(range, cx) { // No provenance in this range, we are done. This is the common case. - return Ok(()); + return; } // This redoes some of the work of `range_get_ptrs_is_empty`, but this path is much @@ -179,28 +203,20 @@ impl<Prov: Provenance> ProvenanceMap<Prov> { // We need to handle clearing the provenance from parts of a pointer. if first < start { - if !Prov::OFFSET_IS_ADDR { - // We can't split up the provenance into less than a pointer. - return Err(AllocError::OverwritePartialPointer(first)); - } // 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 { - bytes.insert(offset, prov); + bytes.insert(offset, (prov, (offset - first).bytes() as u8)); } } if last > end { let begin_of_last = last - pointer_size; - if !Prov::OFFSET_IS_ADDR { - // We can't split up the provenance into less than a pointer. - return Err(AllocError::OverwritePartialPointer(begin_of_last)); - } // 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 { - bytes.insert(offset, prov); + bytes.insert(offset, (prov, (offset - begin_of_last).bytes() as u8)); } } @@ -208,8 +224,6 @@ impl<Prov: Provenance> ProvenanceMap<Prov> { // Since provenance do not overlap, we know that removing until `last` (exclusive) is fine, // i.e., this will not remove any other provenance just after the ones we care about. self.ptrs.remove_range(first..last); - - Ok(()) } /// Overwrites all provenance in the given range with wildcard provenance. @@ -218,10 +232,6 @@ impl<Prov: Provenance> ProvenanceMap<Prov> { /// /// Provided for usage in Miri and panics otherwise. pub fn write_wildcards(&mut self, cx: &impl HasDataLayout, range: AllocRange) { - assert!( - Prov::OFFSET_IS_ADDR, - "writing wildcard provenance is not supported when `OFFSET_IS_ADDR` is false" - ); let wildcard = Prov::WILDCARD.unwrap(); let bytes = self.bytes.get_or_insert_with(Box::default); @@ -229,21 +239,22 @@ impl<Prov: Provenance> ProvenanceMap<Prov> { // Remove pointer provenances that overlap with the range, then readd the edge ones bytewise. let ptr_range = Self::adjusted_range_ptrs(range, cx); let ptrs = self.ptrs.range(ptr_range.clone()); - if let Some((offset, prov)) = ptrs.first() { - for byte_ofs in *offset..range.start { - bytes.insert(byte_ofs, *prov); + if let Some((offset, prov)) = ptrs.first().copied() { + for byte_ofs in offset..range.start { + bytes.insert(byte_ofs, (prov, (byte_ofs - offset).bytes() as u8)); } } - if let Some((offset, prov)) = ptrs.last() { - for byte_ofs in range.end()..*offset + cx.data_layout().pointer_size() { - bytes.insert(byte_ofs, *prov); + if let Some((offset, prov)) = ptrs.last().copied() { + for byte_ofs in range.end()..offset + cx.data_layout().pointer_size() { + bytes.insert(byte_ofs, (prov, (byte_ofs - offset).bytes() as u8)); } } self.ptrs.remove_range(ptr_range); // Overwrite bytewise provenance. for offset in range.start..range.end() { - bytes.insert(offset, wildcard); + // The fragment index does not matter for wildcard provenance. + bytes.insert(offset, (wildcard, 0)); } } } @@ -253,7 +264,7 @@ impl<Prov: Provenance> ProvenanceMap<Prov> { /// Offsets are already adjusted to the destination allocation. pub struct ProvenanceCopy<Prov> { dest_ptrs: Option<Box<[(Size, Prov)]>>, - dest_bytes: Option<Box<[(Size, Prov)]>>, + dest_bytes: Option<Box<[(Size, (Prov, u8))]>>, } impl<Prov: Provenance> ProvenanceMap<Prov> { @@ -263,7 +274,7 @@ impl<Prov: Provenance> ProvenanceMap<Prov> { dest: Size, count: u64, cx: &impl HasDataLayout, - ) -> AllocResult<ProvenanceCopy<Prov>> { + ) -> ProvenanceCopy<Prov> { let shift_offset = move |idx, offset| { // compute offset for current repetition let dest_offset = dest + src.size * idx; // `Size` operations @@ -301,24 +312,16 @@ impl<Prov: Provenance> ProvenanceMap<Prov> { let mut dest_bytes_box = None; let begin_overlap = self.range_ptrs_get(alloc_range(src.start, Size::ZERO), cx).first(); let end_overlap = self.range_ptrs_get(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::ReadPartialPointer(entry.0)); - } - if let Some(entry) = end_overlap { - return Err(AllocError::ReadPartialPointer(entry.0)); - } - debug_assert!(self.bytes.is_none()); - } else { - let mut bytes = Vec::new(); + // We only need to go here if there is some overlap or some bytewise provenance. + if begin_overlap.is_some() || end_overlap.is_some() || self.bytes.is_some() { + let mut bytes: Vec<(Size, (Prov, u8))> = 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)); + bytes.push((offset, (entry.1, (offset - entry.0).bytes() as u8))); } } else { trace!("no start overlapping entry"); @@ -334,8 +337,9 @@ impl<Prov: Provenance> ProvenanceMap<Prov> { let entry_start = cmp::max(entry.0, src.start); for offset in entry_start..src.end() { if bytes.last().is_none_or(|bytes_entry| bytes_entry.0 < offset) { - // The last entry, if it exists, has a lower offset than us. - bytes.push((offset, entry.1)); + // The last entry, if it exists, has a lower offset than us, so we + // can add it at the end and remain sorted. + bytes.push((offset, (entry.1, (offset - entry.0).bytes() as u8))); } 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 @@ -358,7 +362,7 @@ impl<Prov: Provenance> ProvenanceMap<Prov> { dest_bytes_box = Some(dest_bytes.into_boxed_slice()); } - Ok(ProvenanceCopy { dest_ptrs: dest_ptrs_box, dest_bytes: dest_bytes_box }) + ProvenanceCopy { dest_ptrs: dest_ptrs_box, dest_bytes: dest_bytes_box } } /// Applies a provenance copy. @@ -368,14 +372,10 @@ impl<Prov: Provenance> ProvenanceMap<Prov> { if let Some(dest_ptrs) = copy.dest_ptrs { self.ptrs.insert_presorted(dest_ptrs.into()); } - if Prov::OFFSET_IS_ADDR { - 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_none()); + 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()); } } } diff --git a/compiler/rustc_middle/src/mir/interpret/error.rs b/compiler/rustc_middle/src/mir/interpret/error.rs index 2b0cfb86564..d8168697b4a 100644 --- a/compiler/rustc_middle/src/mir/interpret/error.rs +++ b/compiler/rustc_middle/src/mir/interpret/error.rs @@ -577,9 +577,6 @@ pub enum UnsupportedOpInfo { // // The variants below are only reachable from CTFE/const prop, miri will never emit them. // - /// Overwriting parts of a pointer; without knowing absolute addresses, the resulting state - /// cannot be represented by the CTFE interpreter. - OverwritePartialPointer(Pointer<AllocId>), /// Attempting to read or copy parts of a pointer to somewhere else; without knowing absolute /// addresses, the resulting state cannot be represented by the CTFE interpreter. ReadPartialPointer(Pointer<AllocId>), diff --git a/compiler/rustc_middle/src/mir/interpret/pointer.rs b/compiler/rustc_middle/src/mir/interpret/pointer.rs index e25ff7651f6..c581b2ebf09 100644 --- a/compiler/rustc_middle/src/mir/interpret/pointer.rs +++ b/compiler/rustc_middle/src/mir/interpret/pointer.rs @@ -56,7 +56,7 @@ impl<T: HasDataLayout> PointerArithmetic for T {} /// mostly opaque; the `Machine` trait extends it with some more operations that also have access to /// some global state. /// The `Debug` rendering is used to display bare provenance, and for the default impl of `fmt`. -pub trait Provenance: Copy + fmt::Debug + 'static { +pub trait Provenance: Copy + PartialEq + fmt::Debug + 'static { /// Says whether the `offset` field of `Pointer`s with this provenance is the actual physical address. /// - If `false`, the offset *must* be relative. This means the bytes representing a pointer are /// different from what the Abstract Machine prescribes, so the interpreter must prevent any @@ -79,7 +79,7 @@ pub trait Provenance: Copy + fmt::Debug + 'static { fn get_alloc_id(self) -> Option<AllocId>; /// Defines the 'join' of provenance: what happens when doing a pointer load and different bytes have different provenance. - fn join(left: Option<Self>, right: Option<Self>) -> Option<Self>; + fn join(left: Self, right: Self) -> Option<Self>; } /// The type of provenance in the compile-time interpreter. @@ -192,8 +192,8 @@ impl Provenance for CtfeProvenance { Some(self.alloc_id()) } - fn join(_left: Option<Self>, _right: Option<Self>) -> Option<Self> { - panic!("merging provenance is not supported when `OFFSET_IS_ADDR` is false") + fn join(left: Self, right: Self) -> Option<Self> { + if left == right { Some(left) } else { None } } } @@ -224,8 +224,8 @@ impl Provenance for AllocId { Some(self) } - fn join(_left: Option<Self>, _right: Option<Self>) -> Option<Self> { - panic!("merging provenance is not supported when `OFFSET_IS_ADDR` is false") + fn join(_left: Self, _right: Self) -> Option<Self> { + unreachable!() } } diff --git a/compiler/rustc_middle/src/mir/pretty.rs b/compiler/rustc_middle/src/mir/pretty.rs index 809cdb329f7..c0dd9a58f85 100644 --- a/compiler/rustc_middle/src/mir/pretty.rs +++ b/compiler/rustc_middle/src/mir/pretty.rs @@ -1826,7 +1826,7 @@ pub fn write_allocation_bytes<'tcx, Prov: Provenance, Extra, Bytes: AllocBytes>( ascii.push('╼'); i += ptr_size; } - } else if let Some(prov) = alloc.provenance().get(i, &tcx) { + } else if let Some((prov, idx)) = alloc.provenance().get_byte(i, &tcx) { // Memory with provenance must be defined assert!( alloc.init_mask().is_range_initialized(alloc_range(i, Size::from_bytes(1))).is_ok() @@ -1836,7 +1836,7 @@ pub fn write_allocation_bytes<'tcx, Prov: Provenance, Extra, Bytes: AllocBytes>( // Format is similar to "oversized" above. let j = i.bytes_usize(); let c = alloc.inspect_with_uninit_and_ptr_outside_interpreter(j..j + 1)[0]; - write!(w, "╾{c:02x}{prov:#?} (1 ptr byte)╼")?; + write!(w, "╾{c:02x}{prov:#?} (ptr fragment {idx})╼")?; i += Size::from_bytes(1); } else if alloc .init_mask() |