+use rustc::hir::Mutability as TyMutability;
use rustc::mir;
use rustc::ty::layout::{Size, Align};
-use rustc::ty::{self, Ty};
+use rustc::ty::{self, Ty, TypeAndMut};
use rustc_data_structures::indexed_vec::Idx;
use syntax::ast::Mutability;
use error::{EvalError, EvalResult};
use eval_context::EvalContext;
-use memory::MemoryPointer;
-use value::{PrimVal, Value, Pointer};
+use memory::{MemoryPointer, AccessKind};
+use value::{PrimVal, Pointer, Value};
#[derive(Copy, Clone, Debug)]
pub enum Lvalue<'tcx> {
Ok(Lvalue::Ptr { ptr, extra, aligned: aligned && !packed })
}
+ fn val_to_lvalue(&mut self, val: Value, ty: Ty<'tcx>) -> EvalResult<'tcx, Lvalue<'tcx>> {
+ Ok(match self.tcx.struct_tail(ty).sty {
+ ty::TyDynamic(..) => {
+ let (ptr, vtable) = val.into_ptr_vtable_pair(&mut self.memory)?;
+ Lvalue::Ptr { ptr, extra: LvalueExtra::Vtable(vtable), aligned: true }
+ },
+ ty::TyStr | ty::TySlice(_) => {
+ let (ptr, len) = val.into_slice(&mut self.memory)?;
+ Lvalue::Ptr { ptr, extra: LvalueExtra::Length(len), aligned: true }
+ },
+ _ => Lvalue::Ptr { ptr: val.into_ptr(&mut self.memory)?, extra: LvalueExtra::None, aligned: true },
+ })
+ }
+
+ fn lvalue_index(&mut self, base: Lvalue<'tcx>, outer_ty: Ty<'tcx>, n: u64) -> EvalResult<'tcx, Lvalue<'tcx>> {
+ // Taking the outer type here may seem odd; it's needed because for array types, the outer type gives away the length.
+ let base = self.force_allocation(base)?;
+ let (base_ptr, _, aligned) = base.to_ptr_extra_aligned();
+
+ let (elem_ty, len) = base.elem_ty_and_len(outer_ty);
+ let elem_size = self.type_size(elem_ty)?.expect("slice element must be sized");
+ assert!(n < len, "Tried to access element {} of array/slice with length {}", n, len);
+ let ptr = base_ptr.offset(n * elem_size, self.memory.layout)?;
+ Ok(Lvalue::Ptr { ptr, extra: LvalueExtra::None, aligned })
+ }
+
fn eval_lvalue_projection(
&mut self,
base: Lvalue<'tcx>,
trace!("deref to {} on {:?}", pointee_type, val);
- match self.tcx.struct_tail(pointee_type).sty {
- ty::TyDynamic(..) => {
- let (ptr, vtable) = val.into_ptr_vtable_pair(&mut self.memory)?;
- (ptr, LvalueExtra::Vtable(vtable), true)
- },
- ty::TyStr | ty::TySlice(_) => {
- let (ptr, len) = val.into_slice(&mut self.memory)?;
- (ptr, LvalueExtra::Length(len), true)
- },
- _ => (val.into_ptr(&mut self.memory)?, LvalueExtra::None, true),
- }
+ return self.val_to_lvalue(val, pointee_type);
}
Index(ref operand) => {
// FIXME(solson)
- let base = self.force_allocation(base)?;
- let (base_ptr, _, aligned) = base.to_ptr_extra_aligned();
-
- let (elem_ty, len) = base.elem_ty_and_len(base_ty);
- let elem_size = self.type_size(elem_ty)?.expect("slice element must be sized");
let n_ptr = self.eval_operand(operand)?;
let usize = self.tcx.types.usize;
let n = self.value_to_primval(n_ptr, usize)?.to_u64()?;
- assert!(n < len, "Tried to access element {} of array/slice with length {}", n, len);
- let ptr = base_ptr.offset(n * elem_size, &self)?;
- (ptr, LvalueExtra::None, aligned)
+ return self.lvalue_index(base, base_ty, n);
}
ConstantIndex { offset, min_length, from_end } => {
self.monomorphize(lvalue.ty(self.mir(), self.tcx).to_ty(self.tcx), self.substs())
}
}
+
+// Validity checks
+impl<'a, 'tcx> EvalContext<'a, 'tcx> {
+ pub(super) fn acquire_valid(&mut self, lvalue: Lvalue<'tcx>, ty: Ty<'tcx>, outer_mutbl: TyMutability) -> EvalResult<'tcx> {
+ use rustc::ty::TypeVariants::*;
+ use rustc::ty::RegionKind::*;
+ use self::TyMutability::*;
+
+ trace!("Validating {:?} at type {}, outer mutability {:?}", lvalue, ty, outer_mutbl);
+ match ty.sty {
+ TyChar | TyInt(_) | TyUint(_) | TyRawPtr(_) => {
+ // TODO: Make sure these are not undef.
+ // We could do a bounds-check and other sanity checks on the lvalue, but it would be a bug in miri for this to ever fail.
+ Ok(())
+ }
+ TyBool | TyFloat(_) | TyStr => {
+ // TODO: Check if these are valid bool/float/UTF-8, respectively (and in particular, not undef).
+ Ok(())
+ }
+ TyRef(region, TypeAndMut { ty: pointee_ty, mutbl }) => {
+ // Acquire lock
+ let val = self.read_lvalue(lvalue)?;
+ let (len, _) = self.size_and_align_of_dst(pointee_ty, val)?;
+ let ptr = val.into_ptr(&mut self.memory)?.to_ptr()?;
+ let combined_mutbl = match outer_mutbl { MutMutable => mutbl, MutImmutable => MutImmutable };
+ let access = match combined_mutbl { MutMutable => AccessKind::Write, MutImmutable => AccessKind::Read };
+ let region = match *region {
+ ReScope(extent) => Some(extent),
+ _ => None,
+ };
+ self.memory.acquire_lock(ptr, len, region, access)?;
+
+ // Recurse
+ let pointee_lvalue = self.val_to_lvalue(val, pointee_ty)?;
+ self.acquire_valid(pointee_lvalue, pointee_ty, combined_mutbl)
+ }
+ TySlice(elem_ty) => {
+ let len = match lvalue {
+ Lvalue::Ptr { extra: LvalueExtra::Length(len), .. } => len,
+ _ => bug!("acquire_valid of a TySlice given non-slice lvalue: {:?}", lvalue),
+ };
+ for i in 0..len {
+ let inner_lvalue = self.lvalue_index(lvalue, ty, i)?;
+ self.acquire_valid(inner_lvalue, elem_ty, outer_mutbl)?;
+ }
+ Ok(())
+ }
+ TyFnPtr(_sig) => {
+ // TODO: The function names here could need some improvement.
+ let ptr = self.read_lvalue(lvalue)?.into_ptr(&mut self.memory)?.to_ptr()?;
+ self.memory.get_fn(ptr)?;
+ // TODO: Check if the signature matches (should be the same check as what terminator/mod.rs already does on call?).
+ Ok(())
+ }
+ _ => unimplemented!("Unimplemented type encountered when checking validity.")
+ }
+ }
+}
projects / rust.git / blobdiff