Adjust Allocation Bytes used by Miri to custom MiriAllocBytes #3526
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| } else { | ||
| alloc_fn(layout) | ||
| }; | ||
| if ptr.is_null() { |
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You're now checking this even in the size == 0 case, which is unnecessary. You can move this if inside the else { ... } above.
| } | ||
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| impl Clone for MiriAllocBytes { | ||
| fn clone(&self) -> Self { |
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Can you implement this using MiriAllocBytes:: from_bytes(Cow::Borrowed(&*self), ...)? Then you don't need unsafe here. :)
| let alloc_bytes = MiriAllocBytes::alloc_with(size, align, alloc_fn) | ||
| .unwrap_or_else(|layout| alloc::handle_alloc_error(layout)); | ||
| // SAFETY: `alloc_bytes.ptr` and `slice.as_ptr()` are non-null, properly aligned | ||
| // and valid for the `slice.len()`-many bytes to be copied. |
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| // and valid for the `slice.len()`-many bytes to be copied. | |
| // and valid for the `size`-many bytes to be copied. |
| fn as_mut_ptr(&mut self) -> *mut u8 { | ||
| self.ptr | ||
| } | ||
| } |
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Please add a newline at the end. (./miri fmt should do that automatically, and also otherwise will make sure you use standard Rust formatting.)
| @@ -122,7 +122,7 @@ impl VisitProvenance for OpTy<'_, Provenance> { | |||
| } | |||
| } | |||
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| impl VisitProvenance for Allocation<Provenance, AllocExtra<'_>> { | |||
| impl<Bytes: AllocBytes> VisitProvenance for Allocation<Provenance, AllocExtra<'_>, Bytes> { | |||
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| impl<Bytes: AllocBytes> VisitProvenance for Allocation<Provenance, AllocExtra<'_>, Bytes> { | |
| impl VisitProvenance for Allocation<Provenance, AllocExtra<'_>, MiriAllocBytes> { |
| fn from_bytes<'a>(slice: impl Into<Cow<'a, [u8]>>, align: Align) -> Self { | ||
| let slice = slice.into(); | ||
| let size = slice.len(); | ||
| let align = align.bytes().try_into().unwrap(); |
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After rebasing over the latest Miri master, you should be able to use align.bytes_usize() here.
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Co-authored-by: Ralf Jung <post@ralfj.de>
Co-authored-by: Ralf Jung <post@ralfj.de>
Co-authored-by: Ralf Jung <post@ralfj.de>
Preparing for merge from rustc Unblocks #3526.
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If you rebase over the latest Miri master, you should get the updated rustc that includes your PR, so that this one can finally build. :) |
Preparing for merge from rustc Unblocks rust-lang/miri#3526.
Preparing for merge from rustc Unblocks rust-lang/miri#3526.
RalfJung
added
the
S-waiting-on-author
Previously, the
MiriMachineusedtype Bytes = Box<[u8]>for its allocations.This PR swaps this out for a custom
MiriAllocBytestype implemented inalloc_bytes.rs.This is in anticipation of an extension to Miri's FFI, which will require its allocations to take care of alignment (the methods in
impl AllocBytes for Box<[u8]>ignore this_align: Alignargument).Needs rust-lang/rust#124492