diff options
| -rw-r--r-- | src/librustc/lib.rs | 1 | ||||
| -rw-r--r-- | src/librustc/mir/interpret/allocation.rs | 37 | ||||
| -rw-r--r-- | src/librustc_mir/interpret/memory.rs | 21 |
3 files changed, 39 insertions, 20 deletions
diff --git a/src/librustc/lib.rs b/src/librustc/lib.rs index 8943fc342c0..3b0ac9ada8f 100644 --- a/src/librustc/lib.rs +++ b/src/librustc/lib.rs @@ -43,6 +43,7 @@ #![feature(nll)] #![feature(non_exhaustive)] #![feature(optin_builtin_traits)] +#![feature(option_expect_none)] #![feature(range_is_empty)] #![feature(slice_patterns)] #![feature(specialization)] diff --git a/src/librustc/mir/interpret/allocation.rs b/src/librustc/mir/interpret/allocation.rs index 15e6cb6bcab..796d293e2c6 100644 --- a/src/librustc/mir/interpret/allocation.rs +++ b/src/librustc/mir/interpret/allocation.rs @@ -245,6 +245,8 @@ impl<'tcx, Tag: Copy, Extra: AllocationExtra<Tag>> Allocation<Tag, Extra> { /// as a slice. /// /// It is the caller's responsibility to check bounds and alignment beforehand. + /// Most likely, you want to use the `PlaceTy` and `OperandTy`-based methods + /// on `InterpCx` instead. #[inline] pub fn get_bytes( &self, @@ -275,6 +277,8 @@ impl<'tcx, Tag: Copy, Extra: AllocationExtra<Tag>> Allocation<Tag, Extra> { /// so be sure to actually put data there! /// /// It is the caller's responsibility to check bounds and alignment beforehand. + /// Most likely, you want to use the `PlaceTy` and `OperandTy`-based methods + /// on `InterpCx` instead. pub fn get_bytes_mut( &mut self, cx: &impl HasDataLayout, @@ -297,6 +301,8 @@ impl<'tcx, Tag: Copy, Extra: AllocationExtra<Tag>> Allocation<Tag, Extra> { impl<'tcx, Tag: Copy, Extra: AllocationExtra<Tag>> Allocation<Tag, Extra> { /// Reads bytes until a `0` is encountered. Will error if the end of the allocation is reached /// before a `0` is found. + /// + /// Most likely, you want to call `Memory::read_c_str` instead of this method. pub fn read_c_str( &self, cx: &impl HasDataLayout, @@ -342,33 +348,22 @@ impl<'tcx, Tag: Copy, Extra: AllocationExtra<Tag>> Allocation<Tag, Extra> { /// Writes `src` to the memory starting at `ptr.offset`. /// /// It is the caller's responsibility to check bounds and alignment beforehand. + /// Most likely, you want to call `Memory::write_bytes` instead of this method. pub fn write_bytes( &mut self, cx: &impl HasDataLayout, ptr: Pointer<Tag>, - src: &[u8], + src: impl IntoIterator<Item=u8, IntoIter: iter::ExactSizeIterator>, ) -> InterpResult<'tcx> { + let mut src = src.into_iter(); let bytes = self.get_bytes_mut(cx, ptr, Size::from_bytes(src.len() as u64))?; - bytes.clone_from_slice(src); - Ok(()) - } - - /// Sets `count` bytes starting at `ptr.offset` with `val`. Basically `memset`. - /// - /// It is the caller's responsibility to check bounds and alignment beforehand. - pub fn write_repeat( - &mut self, - cx: &impl HasDataLayout, - ptr: Pointer<Tag>, - val: u8, - count: Size - ) -> InterpResult<'tcx> - { - let bytes = self.get_bytes_mut(cx, ptr, count)?; - for b in bytes { - *b = val; + // `zip` would stop when the first iterator ends; we want to definitely + // cover all of `bytes`. + for dest in bytes { + *dest = src.next().expect("iterator was shorter than it said it would be"); } + src.next().expect_none("iterator was longer than it said it would be"); Ok(()) } @@ -380,6 +375,7 @@ impl<'tcx, Tag: Copy, Extra: AllocationExtra<Tag>> Allocation<Tag, Extra> { /// pointers being valid for ZSTs. /// /// It is the caller's responsibility to check bounds and alignment beforehand. + /// Most likely, you want to call `InterpCx::read_scalar` instead of this method. pub fn read_scalar( &self, cx: &impl HasDataLayout, @@ -418,6 +414,7 @@ impl<'tcx, Tag: Copy, Extra: AllocationExtra<Tag>> Allocation<Tag, Extra> { /// Reads a pointer-sized scalar. /// /// It is the caller's responsibility to check bounds and alignment beforehand. + /// Most likely, you want to call `InterpCx::read_scalar` instead of this method. pub fn read_ptr_sized( &self, cx: &impl HasDataLayout, @@ -435,6 +432,7 @@ impl<'tcx, Tag: Copy, Extra: AllocationExtra<Tag>> Allocation<Tag, Extra> { /// pointers being valid for ZSTs. /// /// It is the caller's responsibility to check bounds and alignment beforehand. + /// Most likely, you want to call `InterpCx::write_scalar` instead of this method. pub fn write_scalar( &mut self, cx: &impl HasDataLayout, @@ -477,6 +475,7 @@ impl<'tcx, Tag: Copy, Extra: AllocationExtra<Tag>> Allocation<Tag, Extra> { /// Writes a pointer-sized scalar. /// /// It is the caller's responsibility to check bounds and alignment beforehand. + /// Most likely, you want to call `InterpCx::write_scalar` instead of this method. pub fn write_ptr_sized( &mut self, cx: &impl HasDataLayout, diff --git a/src/librustc_mir/interpret/memory.rs b/src/librustc_mir/interpret/memory.rs index 924474c5317..0b65e9742b6 100644 --- a/src/librustc_mir/interpret/memory.rs +++ b/src/librustc_mir/interpret/memory.rs @@ -7,7 +7,7 @@ //! short-circuiting the empty case! use std::collections::VecDeque; -use std::ptr; +use std::{ptr, iter}; use std::borrow::Cow; use rustc::ty::{self, Instance, ParamEnv, query::TyCtxtAt}; @@ -785,6 +785,25 @@ impl<'mir, 'tcx, M: Machine<'mir, 'tcx>> Memory<'mir, 'tcx, M> { self.get(ptr.alloc_id)?.read_c_str(self, ptr) } + /// Writes the given stream of bytes into memory. + /// + /// Performs appropriate bounds checks. + pub fn write_bytes( + &mut self, + ptr: Scalar<M::PointerTag>, + src: impl IntoIterator<Item=u8, IntoIter: iter::ExactSizeIterator>, + ) -> InterpResult<'tcx> + { + let src = src.into_iter(); + let size = Size::from_bytes(src.len() as u64); + let ptr = match self.check_ptr_access(ptr, size, Align::from_bytes(1).unwrap())? { + Some(ptr) => ptr, + None => return Ok(()), // zero-sized access + }; + let tcx = self.tcx.tcx; + self.get_mut(ptr.alloc_id)?.write_bytes(&tcx, ptr, src) + } + /// Expects the caller to have checked bounds and alignment. pub fn copy( &mut self, |