diff options
author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-17 12:19:43 +0000 |
---|---|---|
committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-17 12:19:43 +0000 |
commit | 3e3e70d529d8c7d7c4d7bc4fefc9f109393b9245 (patch) | |
tree | daf049b282ab10e8c3d03e409b3cd84ff3f7690c /compiler/rustc_middle/src/mir/interpret/allocation.rs | |
parent | Adding debian version 1.68.2+dfsg1-1. (diff) | |
download | rustc-3e3e70d529d8c7d7c4d7bc4fefc9f109393b9245.tar.xz rustc-3e3e70d529d8c7d7c4d7bc4fefc9f109393b9245.zip |
Merging upstream version 1.69.0+dfsg1.
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'compiler/rustc_middle/src/mir/interpret/allocation.rs')
-rw-r--r-- | compiler/rustc_middle/src/mir/interpret/allocation.rs | 82 |
1 files changed, 67 insertions, 15 deletions
diff --git a/compiler/rustc_middle/src/mir/interpret/allocation.rs b/compiler/rustc_middle/src/mir/interpret/allocation.rs index 221105ac4..48375ed30 100644 --- a/compiler/rustc_middle/src/mir/interpret/allocation.rs +++ b/compiler/rustc_middle/src/mir/interpret/allocation.rs @@ -8,7 +8,8 @@ mod tests; use std::borrow::Cow; use std::fmt; use std::hash; -use std::ops::Range; +use std::hash::Hash; +use std::ops::{Deref, DerefMut, Range}; use std::ptr; use either::{Left, Right}; @@ -29,6 +30,39 @@ use provenance_map::*; pub use init_mask::{InitChunk, InitChunkIter}; +/// Functionality required for the bytes of an `Allocation`. +pub trait AllocBytes: + Clone + fmt::Debug + Eq + PartialEq + Hash + Deref<Target = [u8]> + DerefMut<Target = [u8]> +{ + /// Adjust the bytes to the specified alignment -- by default, this is a no-op. + fn adjust_to_align(self, _align: Align) -> Self; + + /// Create an `AllocBytes` from a slice of `u8`. + fn from_bytes<'a>(slice: impl Into<Cow<'a, [u8]>>, _align: Align) -> Self; + + /// Create a zeroed `AllocBytes` of the specified size and alignment; + /// call the callback error handler if there is an error in allocating the memory. + fn zeroed(size: Size, _align: Align) -> Option<Self>; +} + +// Default `bytes` for `Allocation` is a `Box<[u8]>`. +impl AllocBytes for Box<[u8]> { + fn adjust_to_align(self, _align: Align) -> Self { + self + } + + fn from_bytes<'a>(slice: impl Into<Cow<'a, [u8]>>, _align: Align) -> Self { + Box::<[u8]>::from(slice.into()) + } + + fn zeroed(size: Size, _align: Align) -> Option<Self> { + let bytes = Box::<[u8]>::try_new_zeroed_slice(size.bytes_usize()).ok()?; + // SAFETY: the box was zero-allocated, which is a valid initial value for Box<[u8]> + let bytes = unsafe { bytes.assume_init() }; + Some(bytes) + } +} + /// This type represents an Allocation in the Miri/CTFE core engine. /// /// Its public API is rather low-level, working directly with allocation offsets and a custom error @@ -38,10 +72,10 @@ pub use init_mask::{InitChunk, InitChunkIter}; // hashed. (see the `Hash` impl below for more details), so the impl is not derived. #[derive(Clone, Eq, PartialEq, TyEncodable, TyDecodable)] #[derive(HashStable)] -pub struct Allocation<Prov: Provenance = AllocId, Extra = ()> { +pub struct Allocation<Prov: Provenance = AllocId, Extra = (), Bytes = Box<[u8]>> { /// The actual bytes of the allocation. /// Note that the bytes of a pointer represent the offset of the pointer. - bytes: Box<[u8]>, + bytes: Bytes, /// Maps from byte addresses to extra provenance data for each pointer. /// Only the first byte of a pointer is inserted into the map; i.e., /// every entry in this map applies to `pointer_size` consecutive bytes starting @@ -220,14 +254,27 @@ impl AllocRange { } // The constructors are all without extra; the extra gets added by a machine hook later. -impl<Prov: Provenance> Allocation<Prov> { +impl<Prov: Provenance, Bytes: AllocBytes> Allocation<Prov, (), Bytes> { + /// Creates an allocation from an existing `Bytes` value - this is needed for miri FFI support + pub fn from_raw_bytes(bytes: Bytes, align: Align, mutability: Mutability) -> Self { + let size = Size::from_bytes(bytes.len()); + Self { + bytes, + provenance: ProvenanceMap::new(), + init_mask: InitMask::new(size, true), + align, + mutability, + extra: (), + } + } + /// Creates an allocation initialized by the given bytes pub fn from_bytes<'a>( slice: impl Into<Cow<'a, [u8]>>, align: Align, mutability: Mutability, ) -> Self { - let bytes = Box::<[u8]>::from(slice.into()); + let bytes = Bytes::from_bytes(slice, align); let size = Size::from_bytes(bytes.len()); Self { bytes, @@ -248,7 +295,7 @@ impl<Prov: Provenance> Allocation<Prov> { /// /// If `panic_on_fail` is true, this will never return `Err`. pub fn uninit<'tcx>(size: Size, align: Align, panic_on_fail: bool) -> InterpResult<'tcx, Self> { - let bytes = Box::<[u8]>::try_new_zeroed_slice(size.bytes_usize()).map_err(|_| { + let bytes = Bytes::zeroed(size, align).ok_or_else(|| { // This results in an error that can happen non-deterministically, since the memory // available to the compiler can change between runs. Normally queries are always // deterministic. However, we can be non-deterministic here because all uses of const @@ -262,8 +309,7 @@ impl<Prov: Provenance> Allocation<Prov> { }); InterpError::ResourceExhaustion(ResourceExhaustionInfo::MemoryExhausted) })?; - // SAFETY: the box was zero-allocated, which is a valid initial value for Box<[u8]> - let bytes = unsafe { bytes.assume_init() }; + Ok(Allocation { bytes, provenance: ProvenanceMap::new(), @@ -275,7 +321,7 @@ impl<Prov: Provenance> Allocation<Prov> { } } -impl Allocation { +impl<Bytes: AllocBytes> Allocation<AllocId, (), Bytes> { /// Adjust allocation from the ones in tcx to a custom Machine instance /// with a different Provenance and Extra type. pub fn adjust_from_tcx<Prov: Provenance, Extra, Err>( @@ -283,9 +329,11 @@ impl Allocation { cx: &impl HasDataLayout, extra: Extra, mut adjust_ptr: impl FnMut(Pointer<AllocId>) -> Result<Pointer<Prov>, Err>, - ) -> Result<Allocation<Prov, Extra>, Err> { - // Compute new pointer provenance, which also adjusts the bytes. - let mut bytes = self.bytes; + ) -> Result<Allocation<Prov, Extra, Bytes>, Err> { + // Compute new pointer provenance, which also adjusts the bytes, and realign the pointer if + // necessary. + let mut bytes = self.bytes.adjust_to_align(self.align); + let mut new_provenance = Vec::with_capacity(self.provenance.ptrs().len()); let ptr_size = cx.data_layout().pointer_size.bytes_usize(); let endian = cx.data_layout().endian; @@ -311,7 +359,7 @@ impl Allocation { } /// Raw accessors. Provide access to otherwise private bytes. -impl<Prov: Provenance, Extra> Allocation<Prov, Extra> { +impl<Prov: Provenance, Extra, Bytes: AllocBytes> Allocation<Prov, Extra, Bytes> { pub fn len(&self) -> usize { self.bytes.len() } @@ -340,7 +388,11 @@ impl<Prov: Provenance, Extra> Allocation<Prov, Extra> { } /// Byte accessors. -impl<Prov: Provenance, Extra> Allocation<Prov, Extra> { +impl<Prov: Provenance, Extra, Bytes: AllocBytes> Allocation<Prov, Extra, Bytes> { + pub fn base_addr(&self) -> *const u8 { + self.bytes.as_ptr() + } + /// This is the entirely abstraction-violating way to just grab the raw bytes without /// caring about provenance or initialization. /// @@ -412,7 +464,7 @@ impl<Prov: Provenance, Extra> Allocation<Prov, Extra> { } /// Reading and writing. -impl<Prov: Provenance, Extra> Allocation<Prov, Extra> { +impl<Prov: Provenance, Extra, Bytes: AllocBytes> Allocation<Prov, Extra, Bytes> { /// Sets the init bit for the given range. fn mark_init(&mut self, range: AllocRange, is_init: bool) { if range.size.bytes() == 0 { |