diff options
Diffstat (limited to 'compiler/rustc_const_eval/src/interpret/memory.rs')
| -rw-r--r-- | compiler/rustc_const_eval/src/interpret/memory.rs | 51 |
1 files changed, 38 insertions, 13 deletions
diff --git a/compiler/rustc_const_eval/src/interpret/memory.rs b/compiler/rustc_const_eval/src/interpret/memory.rs index 16905e93b..3fde6ae9b 100644 --- a/compiler/rustc_const_eval/src/interpret/memory.rs +++ b/compiler/rustc_const_eval/src/interpret/memory.rs @@ -22,8 +22,8 @@ use crate::fluent_generated as fluent; use super::{ alloc_range, AllocBytes, AllocId, AllocMap, AllocRange, Allocation, CheckAlignMsg, - CheckInAllocMsg, GlobalAlloc, InterpCx, InterpResult, Machine, MayLeak, Misalignment, Pointer, - PointerArithmetic, Provenance, Scalar, + CheckInAllocMsg, CtfeProvenance, GlobalAlloc, InterpCx, InterpResult, Machine, MayLeak, + Misalignment, Pointer, PointerArithmetic, Provenance, Scalar, }; #[derive(Debug, PartialEq, Copy, Clone)] @@ -58,6 +58,7 @@ impl<T: fmt::Display> fmt::Display for MemoryKind<T> { } /// The return value of `get_alloc_info` indicates the "kind" of the allocation. +#[derive(Copy, Clone, PartialEq, Debug)] pub enum AllocKind { /// A regular live data allocation. LiveData, @@ -158,9 +159,9 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> { #[inline] pub fn global_base_pointer( &self, - ptr: Pointer<AllocId>, + ptr: Pointer<CtfeProvenance>, ) -> InterpResult<'tcx, Pointer<M::Provenance>> { - let alloc_id = ptr.provenance; + let alloc_id = ptr.provenance.alloc_id(); // We need to handle `extern static`. match self.tcx.try_get_global_alloc(alloc_id) { Some(GlobalAlloc::Static(def_id)) if self.tcx.is_thread_local_static(def_id) => { @@ -338,7 +339,7 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> { // Let the machine take some extra action let size = alloc.size(); M::before_memory_deallocation( - *self.tcx, + self.tcx, &mut self.machine, &mut alloc.extra, (alloc_id, prov), @@ -473,8 +474,12 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> { match self.ptr_try_get_alloc_id(ptr) { Err(addr) => offset_misalignment(addr, align), Ok((alloc_id, offset, _prov)) => { - let (_size, alloc_align, _kind) = self.get_alloc_info(alloc_id); - if M::use_addr_for_alignment_check(self) { + let (_size, alloc_align, kind) = self.get_alloc_info(alloc_id); + if let Some(misalign) = + M::alignment_check(self, alloc_id, alloc_align, kind, offset, align) + { + Some(misalign) + } else if M::Provenance::OFFSET_IS_ADDR { // `use_addr_for_alignment_check` can only be true if `OFFSET_IS_ADDR` is true. offset_misalignment(ptr.addr().bytes(), align) } else { @@ -501,6 +506,17 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> { } } +impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> { + /// This function is used by Miri's provenance GC to remove unreachable entries from the dead_alloc_map. + pub fn remove_unreachable_allocs(&mut self, reachable_allocs: &FxHashSet<AllocId>) { + // Unlike all the other GC helpers where we check if an `AllocId` is found in the interpreter or + // is live, here all the IDs in the map are for dead allocations so we don't + // need to check for liveness. + #[allow(rustc::potential_query_instability)] // Only used from Miri, not queries. + self.memory.dead_alloc_map.retain(|id, _| reachable_allocs.contains(id)); + } +} + /// Allocation accessors impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> { /// Helper function to obtain a global (tcx) allocation. @@ -545,7 +561,7 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> { (val, Some(def_id)) } }; - M::before_access_global(*self.tcx, &self.machine, id, alloc, def_id, is_write)?; + M::before_access_global(self.tcx, &self.machine, id, alloc, def_id, is_write)?; // We got tcx memory. Let the machine initialize its "extra" stuff. M::adjust_allocation( self, @@ -610,7 +626,7 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> { )?; if let Some((alloc_id, offset, prov, alloc)) = ptr_and_alloc { let range = alloc_range(offset, size); - M::before_memory_read(*self.tcx, &self.machine, &alloc.extra, (alloc_id, prov), range)?; + M::before_memory_read(self.tcx, &self.machine, &alloc.extra, (alloc_id, prov), range)?; Ok(Some(AllocRef { alloc, range, tcx: *self.tcx, alloc_id })) } else { // Even in this branch we have to be sure that we actually access the allocation, in @@ -671,13 +687,13 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> { { let parts = self.get_ptr_access(ptr, size)?; if let Some((alloc_id, offset, prov)) = parts { - let tcx = *self.tcx; + let tcx = self.tcx; // FIXME: can we somehow avoid looking up the allocation twice here? // We cannot call `get_raw_mut` inside `check_and_deref_ptr` as that would duplicate `&mut self`. let (alloc, machine) = self.get_alloc_raw_mut(alloc_id)?; let range = alloc_range(offset, size); M::before_memory_write(tcx, machine, &mut alloc.extra, (alloc_id, prov), range)?; - Ok(Some(AllocRefMut { alloc, range, tcx, alloc_id })) + Ok(Some(AllocRefMut { alloc, range, tcx: *tcx, alloc_id })) } else { Ok(None) } @@ -692,6 +708,15 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> { Ok((&mut alloc.extra, machine)) } + /// Check whether an allocation is live. This is faster than calling + /// [`InterpCx::get_alloc_info`] if all you need to check is whether the kind is + /// [`AllocKind::Dead`] because it doesn't have to look up the type and layout of statics. + pub fn is_alloc_live(&self, id: AllocId) -> bool { + self.tcx.try_get_global_alloc(id).is_some() + || self.memory.alloc_map.contains_key_ref(&id) + || self.memory.extra_fn_ptr_map.contains_key(&id) + } + /// Obtain the size and alignment of an allocation, even if that allocation has /// been deallocated. pub fn get_alloc_info(&self, id: AllocId) -> (Size, Align, AllocKind) { @@ -1108,7 +1133,7 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> { let src_alloc = self.get_alloc_raw(src_alloc_id)?; let src_range = alloc_range(src_offset, size); M::before_memory_read( - *tcx, + tcx, &self.machine, &src_alloc.extra, (src_alloc_id, src_prov), @@ -1138,7 +1163,7 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> { let (dest_alloc, extra) = self.get_alloc_raw_mut(dest_alloc_id)?; let dest_range = alloc_range(dest_offset, size * num_copies); M::before_memory_write( - *tcx, + tcx, extra, &mut dest_alloc.extra, (dest_alloc_id, dest_prov), |