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Improve miri's error reporting in check_in_alloc
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LooMaclin committed Apr 10, 2019
1 parent 9147e26 commit 30a9626
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Showing 2 changed files with 9 additions and 13 deletions.
18 changes: 7 additions & 11 deletions src/librustc/mir/interpret/allocation.rs
Expand Up @@ -239,12 +239,11 @@ impl<'tcx, Tag: Copy, Extra> Allocation<Tag, Extra> {
cx: &impl HasDataLayout,
ptr: Pointer<Tag>,
size: Size,
msg: CheckInAllocMsg,
) -> EvalResult<'tcx, &[u8]>
// FIXME: Working around https://github.com/rust-lang/rust/issues/56209
where Extra: AllocationExtra<Tag, MemoryExtra>
{
self.get_bytes_internal(cx, ptr, size, false, msg)
self.get_bytes_internal(cx, ptr, size, false, CheckInAllocMsg::MemoryAccess)
}

/// Just calling this already marks everything as defined and removes relocations,
Expand All @@ -254,13 +253,12 @@ impl<'tcx, Tag: Copy, Extra> Allocation<Tag, Extra> {
cx: &impl HasDataLayout,
ptr: Pointer<Tag>,
size: Size,
msg: CheckInAllocMsg,
) -> EvalResult<'tcx, &mut [u8]>
// FIXME: Working around https://github.com/rust-lang/rust/issues/56209
where Extra: AllocationExtra<Tag, MemoryExtra>
{
assert_ne!(size.bytes(), 0, "0-sized accesses should never even get a `Pointer`");
self.check_bounds(cx, ptr, size, msg)?;
self.check_bounds(cx, ptr, size, CheckInAllocMsg::MemoryAccess)?;

self.mark_definedness(ptr, size, true)?;
self.clear_relocations(cx, ptr, size)?;
Expand Down Expand Up @@ -314,7 +312,7 @@ impl<'tcx, Tag: Copy, Extra> Allocation<Tag, Extra> {
where Extra: AllocationExtra<Tag, MemoryExtra>
{
// Check bounds and relocations on the edges
self.get_bytes_with_undef_and_ptr(cx, ptr, size, CheckInAllocMsg::OutOfBounds)?;
self.get_bytes_with_undef_and_ptr(cx, ptr, size)?;
// Check undef and ptr
if !allow_ptr_and_undef {
self.check_defined(ptr, size)?;
Expand All @@ -335,8 +333,7 @@ impl<'tcx, Tag: Copy, Extra> Allocation<Tag, Extra> {
// FIXME: Working around https://github.com/rust-lang/rust/issues/56209
where Extra: AllocationExtra<Tag, MemoryExtra>
{
let bytes = self.get_bytes_mut(cx, ptr, Size::from_bytes(src.len() as u64),
CheckInAllocMsg::MemoryAccess)?;
let bytes = self.get_bytes_mut(cx, ptr, Size::from_bytes(src.len() as u64))?;
bytes.clone_from_slice(src);
Ok(())
}
Expand All @@ -352,7 +349,7 @@ impl<'tcx, Tag: Copy, Extra> Allocation<Tag, Extra> {
// FIXME: Working around https://github.com/rust-lang/rust/issues/56209
where Extra: AllocationExtra<Tag, MemoryExtra>
{
let bytes = self.get_bytes_mut(cx, ptr, count, CheckInAllocMsg::MemoryAccess)?;
let bytes = self.get_bytes_mut(cx, ptr, count)?;
for b in bytes {
*b = val;
}
Expand All @@ -377,8 +374,7 @@ impl<'tcx, Tag: Copy, Extra> Allocation<Tag, Extra> {
where Extra: AllocationExtra<Tag, MemoryExtra>
{
// get_bytes_unchecked tests relocation edges
let bytes = self.get_bytes_with_undef_and_ptr(cx, ptr, size,
CheckInAllocMsg::MemoryAccess)?;
let bytes = self.get_bytes_with_undef_and_ptr(cx, ptr, size)?;
// Undef check happens *after* we established that the alignment is correct.
// We must not return Ok() for unaligned pointers!
if self.check_defined(ptr, size).is_err() {
Expand Down Expand Up @@ -455,7 +451,7 @@ impl<'tcx, Tag: Copy, Extra> Allocation<Tag, Extra> {
};

let endian = cx.data_layout().endian;
let dst = self.get_bytes_mut(cx, ptr, type_size, CheckInAllocMsg::MemoryAccess)?;
let dst = self.get_bytes_mut(cx, ptr, type_size)?;
write_target_uint(endian, dst, bytes).unwrap();

// See if we have to also write a relocation
Expand Down
4 changes: 2 additions & 2 deletions src/librustc_mir/interpret/memory.rs
Expand Up @@ -731,10 +731,10 @@ impl<'a, 'mir, 'tcx, M: Machine<'a, 'mir, 'tcx>> Memory<'a, 'mir, 'tcx, M> {

// This checks relocation edges on the src.
let src_bytes = self.get(src.alloc_id)?
.get_bytes_with_undef_and_ptr(&tcx, src, size, CheckInAllocMsg::MemoryAccess)?
.get_bytes_with_undef_and_ptr(&tcx, src, size)?
.as_ptr();
let dest_bytes = self.get_mut(dest.alloc_id)?
.get_bytes_mut(&tcx, dest, size * length, CheckInAllocMsg::MemoryAccess)?
.get_bytes_mut(&tcx, dest, size * length)?
.as_mut_ptr();

// SAFE: The above indexing would have panicked if there weren't at least `size` bytes
Expand Down

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