Merge branch 'master' of https://github.com/tsion/miri

src/interpreter/cast.rs

@@ -28,7 +28,7 @@ impl<'a, 'tcx> EvalContext<'a, 'tcx> {
             U64(u) |
             IntegerPtr(u) => self.cast_const_int(u, ty, false),
             FnPtr(ptr) |
-            AbstractPtr(ptr) => self.cast_ptr(ptr, ty),
+            Ptr(ptr) => self.cast_ptr(ptr, ty),
         }
     }
 
@@ -36,7 +36,7 @@ impl<'a, 'tcx> EvalContext<'a, 'tcx> {
         use primval::PrimVal::*;
         match ty.sty {
             ty::TyRef(..) |
-            ty::TyRawPtr(_) => Ok(AbstractPtr(ptr)),
+            ty::TyRawPtr(_) => Ok(Ptr(ptr)),
             ty::TyFnPtr(_) => Ok(FnPtr(ptr)),
             _ => Err(EvalError::Unimplemented(format!("ptr to {:?} cast", ty))),
         }

src/interpreter/mod.rs

@@ -246,7 +246,7 @@ impl<'a, 'tcx> EvalContext<'a, 'tcx> {
                 self.memory.write_bytes(ptr, s.as_bytes())?;
                 self.memory.freeze(ptr.alloc_id)?;
                 Value::ByValPair(
-                    PrimVal::AbstractPtr(ptr),
+                    PrimVal::Ptr(ptr),
                     self.target_usize_primval(s.len() as u64)
                 )
             }
@@ -255,7 +255,7 @@ impl<'a, 'tcx> EvalContext<'a, 'tcx> {
                 let ptr = self.memory.allocate(bs.len(), 1)?;
                 self.memory.write_bytes(ptr, bs)?;
                 self.memory.freeze(ptr.alloc_id)?;
-                Value::ByVal(PrimVal::AbstractPtr(ptr))
+                Value::ByVal(PrimVal::Ptr(ptr))
             }
 
             Struct(_)    => unimplemented!(),
@@ -782,31 +782,8 @@ impl<'a, 'tcx> EvalContext<'a, 'tcx> {
     // remove it as soon as PrimVal can represent fat pointers.
     fn eval_operand_to_ptr(&mut self, op: &mir::Operand<'tcx>) -> EvalResult<'tcx, Pointer> {
         let value = self.eval_operand(op)?;
-        match value {
+        let ty = self.operand_ty(op);
-            Value::ByRef(ptr) => Ok(ptr),
+        self.value_to_ptr(value, ty)
-
-            Value::ByVal(primval) => {
-                let ty = self.operand_ty(op);
-                let size = self.type_size(ty);
-                let align = self.type_align(ty);
-                let ptr = self.memory.allocate(size, align)?;
-                self.memory.write_primval(ptr, primval)?;
-                Ok(ptr)
-            }
-
-            Value::ByValPair(primval1, primval2) => {
-                let ty = self.operand_ty(op);
-                let size = self.type_size(ty);
-                let align = self.type_align(ty);
-                let ptr = self.memory.allocate(size, align)?;
-
-                // FIXME(solson): Major dangerous assumptions here. Ideally obliterate this
-                // function.
-                self.memory.write_primval(ptr, primval1)?;
-                self.memory.write_primval(ptr.offset((size / 2) as isize), primval2)?;
-                Ok(ptr)
-            }
-        }
     }
 
     fn eval_operand_to_primval(&mut self, op: &mir::Operand<'tcx>) -> EvalResult<'tcx, PrimVal> {
@@ -992,6 +969,34 @@ impl<'a, 'tcx> EvalContext<'a, 'tcx> {
         Ok(())
     }
 
+    // FIXME(solson): This method unnecessarily allocates and should not be necessary. We can
+    // remove it as soon as PrimVal can represent fat pointers.
+    fn value_to_ptr(&mut self, value: Value, ty: Ty<'tcx>) -> EvalResult<'tcx, Pointer> {
+        match value {
+            Value::ByRef(ptr) => Ok(ptr),
+
+            Value::ByVal(primval) => {
+                let size = self.type_size(ty);
+                let align = self.type_align(ty);
+                let ptr = self.memory.allocate(size, align)?;
+                self.memory.write_primval(ptr, primval)?;
+                Ok(ptr)
+            }
+
+            Value::ByValPair(primval1, primval2) => {
+                let size = self.type_size(ty);
+                let align = self.type_align(ty);
+                let ptr = self.memory.allocate(size, align)?;
+
+                // FIXME(solson): Major dangerous assumptions here. Ideally obliterate this
+                // function.
+                self.memory.write_primval(ptr, primval1)?;
+                self.memory.write_primval(ptr.offset((size / 2) as isize), primval2)?;
+                Ok(ptr)
+            }
+        }
+    }
+
     fn value_to_primval(&mut self, value: Value, ty: Ty<'tcx>) -> EvalResult<'tcx, PrimVal> {
         match value {
             Value::ByRef(ptr) => self.read_primval(ptr, ty),
@@ -1057,7 +1062,7 @@ impl<'a, 'tcx> EvalContext<'a, 'tcx> {
             &ty::TyRawPtr(ty::TypeAndMut { ty, .. }) => {
                 if self.type_is_sized(ty) {
                     match self.memory.read_ptr(ptr) {
-                        Ok(p) => PrimVal::AbstractPtr(p),
+                        Ok(p) => PrimVal::Ptr(p),
                         Err(EvalError::ReadBytesAsPointer) => {
                             PrimVal::IntegerPtr(self.memory.read_usize(ptr)?)
                         }

src/interpreter/step.rs

@@ -82,6 +82,10 @@ impl<'a, 'tcx> EvalContext<'a, 'tcx> {
 
             // Miri can safely ignore these. Only translation needs them.
             StorageLive(_) | StorageDead(_) => {}
+
+            // Defined to do nothing. These are added by optimization passes, to avoid changing the
+            // size of MIR constantly.
+            Nop => {}
         }
 
         self.frame_mut().stmt += 1;
@@ -186,12 +190,18 @@ impl<'a, 'b, 'tcx> Visitor<'tcx> for ConstantExtractor<'a, 'b, 'tcx> {
         }
     }
 
-    fn visit_lvalue(&mut self, lvalue: &mir::Lvalue<'tcx>, context: LvalueContext, location: mir::Location) {
+    fn visit_lvalue(
+        &mut self,
+        lvalue: &mir::Lvalue<'tcx>,
+        context: LvalueContext<'tcx>,
+        location: mir::Location
+    ) {
         self.super_lvalue(lvalue, context, location);
         if let mir::Lvalue::Static(def_id) = *lvalue {
             let substs = subst::Substs::empty(self.ecx.tcx);
             let span = self.span;
-            if let hir::map::Node::NodeItem(&hir::Item { ref node, .. }) = self.ecx.tcx.map.get_if_local(def_id).expect("static not found") {
+            let node_item = self.ecx.tcx.map.get_if_local(def_id).expect("static not found");
+            if let hir::map::Node::NodeItem(&hir::Item { ref node, .. }) = node_item {
                 if let hir::ItemStatic(_, m, _) = *node {
                     self.global_item(def_id, substs, span, m == hir::MutImmutable);
                     return;

src/interpreter/terminator/mod.rs

@@ -13,7 +13,8 @@ use syntax::{ast, attr};
 
 use error::{EvalError, EvalResult};
 use memory::Pointer;
-use super::{EvalContext, IntegerExt, StackPopCleanup};
+use primval::PrimVal;
+use super::{EvalContext, IntegerExt, StackPopCleanup, Value};
 
 mod intrinsics;
 
@@ -154,7 +155,7 @@ impl<'a, 'tcx> EvalContext<'a, 'tcx> {
         substs: &'tcx Substs<'tcx>,
         fn_ty: &'tcx BareFnTy,
         destination: Option<(Pointer, mir::BasicBlock)>,
-        args: &[mir::Operand<'tcx>],
+        arg_operands: &[mir::Operand<'tcx>],
         span: Span,
     ) -> EvalResult<'tcx, ()> {
         use syntax::abi::Abi;
@@ -163,7 +164,7 @@ impl<'a, 'tcx> EvalContext<'a, 'tcx> {
                 let ty = fn_ty.sig.0.output;
                 let layout = self.type_layout(ty);
                 let (ret, target) = destination.unwrap();
-                self.call_intrinsic(def_id, substs, args, ret, layout)?;
+                self.call_intrinsic(def_id, substs, arg_operands, ret, layout)?;
                 self.goto_block(target);
                 Ok(())
             }
@@ -172,23 +173,23 @@ impl<'a, 'tcx> EvalContext<'a, 'tcx> {
                 let ty = fn_ty.sig.0.output;
                 let size = self.type_size(ty);
                 let (ret, target) = destination.unwrap();
-                self.call_c_abi(def_id, args, ret, size)?;
+                self.call_c_abi(def_id, arg_operands, ret, size)?;
                 self.goto_block(target);
                 Ok(())
             }
 
             Abi::Rust | Abi::RustCall => {
-                let mut arg_srcs = Vec::new();
+                let mut args = Vec::new();
-                for arg in args {
+                for arg in arg_operands {
-                    let src = self.eval_operand_to_ptr(arg)?;
+                    let arg_val = self.eval_operand(arg)?;
-                    let src_ty = self.operand_ty(arg);
+                    let arg_ty = self.operand_ty(arg);
-                    arg_srcs.push((src, src_ty));
+                    args.push((arg_val, arg_ty));
                 }
 
                 // Only trait methods can have a Self parameter.
                 let (resolved_def_id, resolved_substs) =
                     if let Some(trait_id) = self.tcx.trait_of_item(def_id) {
-                        self.trait_method(trait_id, def_id, substs, &mut arg_srcs)?
+                        self.trait_method(trait_id, def_id, substs, &mut args)?
                     } else {
                         (def_id, substs)
                     };
@@ -200,9 +201,9 @@ impl<'a, 'tcx> EvalContext<'a, 'tcx> {
                 };
                 self.push_stack_frame(resolved_def_id, span, mir, resolved_substs, return_ptr, return_to_block)?;
 
-                for (i, (src, src_ty)) in arg_srcs.into_iter().enumerate() {
+                for (i, (arg_val, arg_ty)) in args.into_iter().enumerate() {
                     let dest = self.frame().locals[i];
-                    self.move_(src, dest, src_ty)?;
+                    self.write_value(arg_val, dest, arg_ty)?;
                 }
 
                 Ok(())
@@ -344,7 +345,7 @@ impl<'a, 'tcx> EvalContext<'a, 'tcx> {
         })
     }
 
-    fn unpack_fn_args(&self, args: &mut Vec<(Pointer, Ty<'tcx>)>) {
+    fn unpack_fn_args(&self, args: &mut Vec<(Value, Ty<'tcx>)>) {
         if let Some((last, last_ty)) = args.pop() {
             let last_layout = self.type_layout(last_ty);
             match (&last_ty.sty, last_layout) {
@@ -353,9 +354,13 @@ impl<'a, 'tcx> EvalContext<'a, 'tcx> {
                     let offsets = iter::once(0)
                         .chain(variant.offset_after_field.iter()
                             .map(|s| s.bytes()));
+                    let last_ptr = match last {
+                        Value::ByRef(ptr) => ptr,
+                        _ => bug!("rust-call ABI tuple argument wasn't Value::ByRef"),
+                    };
                     for (offset, ty) in offsets.zip(fields) {
-                        let src = last.offset(offset as isize);
+                        let arg = Value::ByRef(last_ptr.offset(offset as isize));
-                        args.push((src, ty));
+                        args.push((arg, ty));
                     }
                 }
                 ty => bug!("expected tuple as last argument in function with 'rust-call' ABI, got {:?}", ty),
@@ -369,7 +374,7 @@ impl<'a, 'tcx> EvalContext<'a, 'tcx> {
         trait_id: DefId,
         def_id: DefId,
         substs: &'tcx Substs<'tcx>,
-        args: &mut Vec<(Pointer, Ty<'tcx>)>,
+        args: &mut Vec<(Value, Ty<'tcx>)>,
     ) -> EvalResult<'tcx, (DefId, &'tcx Substs<'tcx>)> {
         let trait_ref = ty::TraitRef::from_method(self.tcx, trait_id, substs);
         let trait_ref = self.tcx.normalize_associated_type(&ty::Binder(trait_ref));
@@ -398,6 +403,7 @@ impl<'a, 'tcx> EvalContext<'a, 'tcx> {
                     (ty::ClosureKind::FnMut, ty::ClosureKind::FnMut) |
                     (ty::ClosureKind::FnOnce, ty::ClosureKind::FnOnce) |
                     (ty::ClosureKind::Fn, ty::ClosureKind::FnMut) => {} // No adapter needed.
+
                     (ty::ClosureKind::Fn, ty::ClosureKind::FnOnce) |
                     (ty::ClosureKind::FnMut, ty::ClosureKind::FnOnce) => {
                         // The closure fn is a `fn(&self, ...)` or `fn(&mut self, ...)`.
@@ -409,13 +415,15 @@ impl<'a, 'tcx> EvalContext<'a, 'tcx> {
                         //
                         // These are both the same at trans time.
 
-                        // interpreter magic: insert an intermediate pointer, so we can skip the intermediate function call
+                        // Interpreter magic: insert an intermediate pointer, so we can skip the
-                        // FIXME: this is a memory leak, should probably add the pointer to the current stack
+                        // intermediate function call.
-                        let ptr_size = self.memory.pointer_size();
+                        // FIXME: this is a memory leak, should probably add the pointer to the
-                        let first = self.memory.allocate(ptr_size, ptr_size)?;
+                        // current stack.
-                        self.memory.copy(args[0].0, first, ptr_size, ptr_size)?;
+                        let first = self.value_to_ptr(args[0].0, args[0].1)?;
-                        self.memory.write_ptr(args[0].0, first)?;
+                        args[0].0 = Value::ByVal(PrimVal::Ptr(first));
+                        args[0].1 = self.tcx.mk_mut_ptr(args[0].1);
                     }
+
                     _ => bug!("cannot convert {:?} to {:?}", closure_kind, trait_closure_kind),
                 }
                 Ok((vtable_closure.closure_def_id, vtable_closure.substs.func_substs))
@@ -433,8 +441,11 @@ impl<'a, 'tcx> EvalContext<'a, 'tcx> {
 
             traits::VtableObject(ref data) => {
                 let idx = self.tcx.get_vtable_index_of_object_method(data, def_id);
-                if let Some(&mut(first_arg, ref mut first_ty)) = args.get_mut(0) {
+                if let Some(&mut(ref mut first_arg, ref mut first_ty)) = args.get_mut(0) {
-                    let (_, vtable) = self.get_fat_ptr(first_arg);
+                    // FIXME(solson): Remove this allocating hack.
+                    let ptr = self.value_to_ptr(*first_arg, *first_ty)?;
+                    *first_arg = Value::ByRef(ptr);
+                    let (_, vtable) = self.get_fat_ptr(ptr);
                     let vtable = self.memory.read_ptr(vtable)?;
                     let idx = idx + 3;
                     let offset = idx * self.memory.pointer_size();

src/memory.rs

@@ -530,7 +530,7 @@ impl<'a, 'tcx> Memory<'a, 'tcx> {
             PrimVal::F32(f) => self.write_f32(ptr, f),
             PrimVal::F64(f) => self.write_f64(ptr, f),
             PrimVal::FnPtr(p) |
-            PrimVal::AbstractPtr(p) => self.write_ptr(ptr, p),
+            PrimVal::Ptr(p) => self.write_ptr(ptr, p),
         }
     }
 

src/primval.rs

@@ -12,7 +12,7 @@ pub enum PrimVal {
     I8(i8), I16(i16), I32(i32), I64(i64),
     U8(u8), U16(u16), U32(u32), U64(u64),
 
-    AbstractPtr(Pointer),
+    Ptr(Pointer),
     FnPtr(Pointer),
     IntegerPtr(u64),
     Char(char),
@@ -211,10 +211,10 @@ pub fn binary_op<'tcx>(bin_op: mir::BinOp, left: PrimVal, right: PrimVal) -> Eva
 
         (IntegerPtr(l), IntegerPtr(r)) => int_binops!(IntegerPtr, l, r),
 
-        (AbstractPtr(_), IntegerPtr(_)) |
+        (Ptr(_), IntegerPtr(_)) |
-        (IntegerPtr(_), AbstractPtr(_)) |
+        (IntegerPtr(_), Ptr(_)) |
-        (FnPtr(_), AbstractPtr(_)) |
+        (FnPtr(_), Ptr(_)) |
-        (AbstractPtr(_), FnPtr(_)) |
+        (Ptr(_), FnPtr(_)) |
         (FnPtr(_), IntegerPtr(_)) |
         (IntegerPtr(_), FnPtr(_)) =>
             unrelated_ptr_ops(bin_op)?,
@@ -225,7 +225,7 @@ pub fn binary_op<'tcx>(bin_op: mir::BinOp, left: PrimVal, right: PrimVal) -> Eva
             _ => return Err(EvalError::Unimplemented(format!("unimplemented fn ptr comparison: {:?}", bin_op))),
         },
 
-        (AbstractPtr(l_ptr), AbstractPtr(r_ptr)) => {
+        (Ptr(l_ptr), Ptr(r_ptr)) => {
             if l_ptr.alloc_id != r_ptr.alloc_id {
                 return Ok((unrelated_ptr_ops(bin_op)?, false));
             }