Auto merge of #37220 - Mark-Simulacrum:arena-alloc-slice, r=eddyb

alloc_slice in TypedArena

Added `TypedArena::alloc_slice`, and moved from using `TypedArena<Vec<T>>` to `TypedArena<T>`.

`TypedArena::alloc_slice` is implemented by copying the slices elements into the typed arena, requiring that `T: Copy` when using it. We allocate a new chunk when there's insufficient space remaining in the previous chunk, and we cannot resize the old chunk in place. This is non-optimal, since we may waste allocated space when allocating (especially longer) slices, but is considered good enough for the time being.

This change also reduces heap fragmentation, since the arena now directly stores objects instead of storing the Vec's length and pointer to its contents.

Performance:
```
futures-rs-test  5.048s vs  5.061s --> 0.997x faster (variance: 1.028x, 1.020x)
helloworld       0.284s vs  0.295s --> 0.963x faster (variance: 1.207x, 1.189x)
html5ever-2016-  8.396s vs  8.208s --> 1.023x faster (variance: 1.019x, 1.036x)
hyper.0.5.0      5.768s vs  5.797s --> 0.995x faster (variance: 1.027x, 1.028x)
inflate-0.1.0    5.213s vs  5.069s --> 1.028x faster (variance: 1.008x, 1.022x)
issue-32062-equ  0.428s vs  0.467s --> 0.916x faster (variance: 1.188x, 1.015x)
issue-32278-big  1.949s vs  2.010s --> 0.970x faster (variance: 1.112x, 1.049x)
jld-day15-parse  1.795s vs  1.877s --> 0.956x faster (variance: 1.037x, 1.015x)
piston-image-0. 13.554s vs 13.522s --> 1.002x faster (variance: 1.019x, 1.020x)
rust-encoding-0  2.489s vs  2.465s --> 1.010x faster (variance: 1.047x, 1.086x)
syntex-0.42.2   34.646s vs 34.593s --> 1.002x faster (variance: 1.007x, 1.005x)
syntex-0.42.2-i 17.181s vs 17.163s --> 1.001x faster (variance: 1.004x, 1.004x)
```

r? @eddyb

19 files changed, 93 insertions, 56 deletions

diff --git a/src/libarena/lib.rs b/src/libarena/lib.rs
index 4986c9850d7..cfbd29571f7 100644
--- a/src/libarena/lib.rs
+++ b/src/libarena/lib.rs
@@ -46,6 +46,7 @@ use std::intrinsics;
 use std::marker::{PhantomData, Send};
 use std::mem;
 use std::ptr;
+use std::slice;
 
 use alloc::heap;
 use alloc::raw_vec::RawVec;
@@ -133,7 +134,7 @@ impl<T> TypedArena<T> {
     #[inline]
     pub fn alloc(&self, object: T) -> &mut T {
         if self.ptr == self.end {
-            self.grow()
+            self.grow(1)
         }
 
         unsafe {
@@ -154,24 +155,56 @@ impl<T> TypedArena<T> {
         }
     }
 
+    /// Allocates a slice of objects that are copy into the `TypedArena`, returning a mutable
+    /// reference to it. Will panic if passed a zero-sized types.
+    #[inline]
+    pub fn alloc_slice(&self, slice: &[T]) -> &mut [T]
+        where T: Copy {
+        assert!(mem::size_of::<T>() != 0);
+        if slice.len() == 0 {
+            return unsafe { slice::from_raw_parts_mut(heap::EMPTY as *mut T, 0) };
+        }
+
+        let available_capacity_bytes = self.end.get() as usize - self.ptr.get() as usize;
+        let at_least_bytes = slice.len() * mem::size_of::<T>();
+        if available_capacity_bytes < at_least_bytes {
+            self.grow(slice.len());
+        }
+
+        unsafe {
+            let start_ptr = self.ptr.get();
+            let arena_slice = slice::from_raw_parts_mut(start_ptr, slice.len());
+            self.ptr.set(start_ptr.offset(arena_slice.len() as isize));
+            arena_slice.copy_from_slice(slice);
+            arena_slice
+        }
+    }
+
     /// Grows the arena.
     #[inline(never)]
     #[cold]
-    fn grow(&self) {
+    fn grow(&self, n: usize) {
         unsafe {
             let mut chunks = self.chunks.borrow_mut();
-            let (chunk, new_capacity);
+            let (chunk, mut new_capacity);
             if let Some(last_chunk) = chunks.last_mut() {
-                if last_chunk.storage.double_in_place() {
+                let used_bytes = self.ptr.get() as usize - last_chunk.start() as usize;
+                let currently_used_cap = used_bytes / mem::size_of::<T>();
+                if last_chunk.storage.reserve_in_place(currently_used_cap, n) {
                     self.end.set(last_chunk.end());
                     return;
                 } else {
                     let prev_capacity = last_chunk.storage.cap();
-                    new_capacity = prev_capacity.checked_mul(2).unwrap();
+                    loop {
+                        new_capacity = prev_capacity.checked_mul(2).unwrap();
+                        if new_capacity >= currently_used_cap + n {
+                            break;
+                        }
+                    }
                 }
             } else {
                 let elem_size = cmp::max(1, mem::size_of::<T>());
-                new_capacity = cmp::max(1, PAGE / elem_size);
+                new_capacity = cmp::max(n, PAGE / elem_size);
             }
             chunk = TypedArenaChunk::<T>::new(new_capacity);
             self.ptr.set(chunk.start());
diff --git a/src/librustc/mir/tcx.rs b/src/librustc/mir/tcx.rs
index 960d61adba7..6fe6498ff78 100644
--- a/src/librustc/mir/tcx.rs
+++ b/src/librustc/mir/tcx.rs
@@ -163,7 +163,7 @@ impl<'tcx> Rvalue<'tcx> {
                 let lhs_ty = lhs.ty(mir, tcx);
                 let rhs_ty = rhs.ty(mir, tcx);
                 let ty = op.ty(tcx, lhs_ty, rhs_ty);
-                let ty = tcx.mk_tup(vec![ty, tcx.types.bool]);
+                let ty = tcx.mk_tup(&[ty, tcx.types.bool]);
                 Some(ty)
             }
             &Rvalue::UnaryOp(_, ref operand) => {
@@ -184,7 +184,7 @@ impl<'tcx> Rvalue<'tcx> {
                     }
                     AggregateKind::Tuple => {
                         Some(tcx.mk_tup(
-                            ops.iter().map(|op| op.ty(mir, tcx)).collect()
+                            &ops.iter().map(|op| op.ty(mir, tcx)).collect::<Vec<_>>()
                         ))
                     }
                     AggregateKind::Adt(def, _, substs, _) => {
diff --git a/src/librustc/traits/util.rs b/src/librustc/traits/util.rs
index 2cefc2ad796..fa951b5efdb 100644
--- a/src/librustc/traits/util.rs
+++ b/src/librustc/traits/util.rs
@@ -486,7 +486,7 @@ impl<'a, 'gcx, 'tcx> TyCtxt<'a, 'gcx, 'tcx> {
     {
         let arguments_tuple = match tuple_arguments {
             TupleArgumentsFlag::No => sig.0.inputs[0],
-            TupleArgumentsFlag::Yes => self.mk_tup(sig.0.inputs.to_vec()),
+            TupleArgumentsFlag::Yes => self.mk_tup(&sig.0.inputs),
         };
         let trait_ref = ty::TraitRef {
             def_id: fn_trait_def_id,
diff --git a/src/librustc/ty/context.rs b/src/librustc/ty/context.rs
index 8352d6bed50..d075b08f738 100644
--- a/src/librustc/ty/context.rs
+++ b/src/librustc/ty/context.rs
@@ -54,8 +54,8 @@ use hir;
 pub struct CtxtArenas<'tcx> {
     // internings
     type_: TypedArena<TyS<'tcx>>,
-    type_list: TypedArena<Vec<Ty<'tcx>>>,
-    substs: TypedArena<Vec<Kind<'tcx>>>,
+    type_list: TypedArena<Ty<'tcx>>,
+    substs: TypedArena<Kind<'tcx>>,
     bare_fn: TypedArena<BareFnTy<'tcx>>,
     region: TypedArena<Region>,
     stability: TypedArena<attr::Stability>,
@@ -1117,6 +1117,7 @@ impl<'tcx> Borrow<Region> for Interned<'tcx, Region> {
 
 macro_rules! intern_method {
     ($lt_tcx:tt, $name:ident: $method:ident($alloc:ty,
+                                            $alloc_method:ident,
                                             $alloc_to_key:expr,
                                             $alloc_to_ret:expr,
                                             $needs_infer:expr) -> $ty:ty) => {
@@ -1142,7 +1143,8 @@ macro_rules! intern_method {
                         let v = unsafe {
                             mem::transmute(v)
                         };
-                        let i = ($alloc_to_ret)(self.global_interners.arenas.$name.alloc(v));
+                        let i = ($alloc_to_ret)(self.global_interners.arenas.$name
+                                                    .$alloc_method(v));
                         self.global_interners.$name.borrow_mut().insert(Interned(i));
                         return i;
                     }
@@ -1156,7 +1158,7 @@ macro_rules! intern_method {
                     }
                 }
 
-                let i = ($alloc_to_ret)(self.interners.arenas.$name.alloc(v));
+                let i = ($alloc_to_ret)(self.interners.arenas.$name.$alloc_method(v));
                 self.interners.$name.borrow_mut().insert(Interned(i));
                 i
             }
@@ -1180,7 +1182,7 @@ macro_rules! direct_interners {
             }
         }
 
-        intern_method!($lt_tcx, $name: $method($ty, |x| x, |x| x, $needs_infer) -> $ty);)+
+        intern_method!($lt_tcx, $name: $method($ty, alloc, |x| x, |x| x, $needs_infer) -> $ty);)+
     }
 }
 
@@ -1200,16 +1202,18 @@ direct_interners!('tcx,
     }) -> Region
 );
 
-intern_method!('tcx,
-    type_list: mk_type_list(Vec<Ty<'tcx>>, Deref::deref, |xs: &[Ty]| -> &Slice<Ty> {
-        unsafe { mem::transmute(xs) }
-    }, keep_local) -> Slice<Ty<'tcx>>
-);
+macro_rules! slice_interners {
+    ($($field:ident: $method:ident($ty:ident)),+) => (
+        $(intern_method!('tcx, $field: $method(&[$ty<'tcx>], alloc_slice, Deref::deref,
+                                               |xs: &[$ty]| -> &Slice<$ty> {
+            unsafe { mem::transmute(xs) }
+        }, |xs: &[$ty]| xs.iter().any(keep_local)) -> Slice<$ty<'tcx>>);)+
+    )
+}
 
-intern_method!('tcx,
-    substs: mk_substs(Vec<Kind<'tcx>>, Deref::deref, |xs: &[Kind]| -> &Slice<Kind> {
-        unsafe { mem::transmute(xs) }
-    }, keep_local) -> Slice<Kind<'tcx>>
+slice_interners!(
+    type_list: mk_type_list(Ty),
+    substs: mk_substs(Kind)
 );
 
 impl<'a, 'gcx, 'tcx> TyCtxt<'a, 'gcx, 'tcx> {
@@ -1314,12 +1318,12 @@ impl<'a, 'gcx, 'tcx> TyCtxt<'a, 'gcx, 'tcx> {
         self.mk_ty(TySlice(ty))
     }
 
-    pub fn mk_tup(self, ts: Vec<Ty<'tcx>>) -> Ty<'tcx> {
+    pub fn mk_tup(self, ts: &[Ty<'tcx>]) -> Ty<'tcx> {
         self.mk_ty(TyTuple(self.mk_type_list(ts)))
     }
 
     pub fn mk_nil(self) -> Ty<'tcx> {
-        self.mk_tup(Vec::new())
+        self.mk_tup(&[])
     }
 
     pub fn mk_diverging_default(self) -> Ty<'tcx> {
@@ -1361,7 +1365,7 @@ impl<'a, 'gcx, 'tcx> TyCtxt<'a, 'gcx, 'tcx> {
     pub fn mk_closure(self,
                       closure_id: DefId,
                       substs: &'tcx Substs<'tcx>,
-                      tys: Vec<Ty<'tcx>>)
+                      tys: &[Ty<'tcx>])
                       -> Ty<'tcx> {
         self.mk_closure_from_closure_substs(closure_id, ClosureSubsts {
             func_substs: substs,
diff --git a/src/librustc/ty/mod.rs b/src/librustc/ty/mod.rs
index 03d0e1e41be..018f01e5913 100644
--- a/src/librustc/ty/mod.rs
+++ b/src/librustc/ty/mod.rs
@@ -1797,7 +1797,7 @@ impl<'a, 'tcx> AdtDefData<'tcx, 'tcx> {
             _ if tys.references_error() => tcx.types.err,
             0 => tcx.types.bool,
             1 => tys[0],
-            _ => tcx.mk_tup(tys)
+            _ => tcx.mk_tup(&tys)
         };
 
         match self.sized_constraint.get(dep_node()) {
diff --git a/src/librustc/ty/relate.rs b/src/librustc/ty/relate.rs
index b10c731fe27..48b0b4ec9e5 100644
--- a/src/librustc/ty/relate.rs
+++ b/src/librustc/ty/relate.rs
@@ -491,8 +491,8 @@ pub fn super_relate_tys<'a, 'gcx, 'tcx, R>(relation: &mut R,
             if as_.len() == bs.len() {
                 let ts = as_.iter().zip(bs)
                             .map(|(a, b)| relation.relate(a, b))
-                            .collect::<Result<_, _>>()?;
-                Ok(tcx.mk_tup(ts))
+                            .collect::<Result<Vec<_>, _>>()?;
+                Ok(tcx.mk_tup(&ts))
             } else if !(as_.is_empty() || bs.is_empty()) {
                 Err(TypeError::TupleSize(
                     expected_found(relation, &as_.len(), &bs.len())))
@@ -547,7 +547,7 @@ impl<'tcx> Relate<'tcx> for ty::ClosureSubsts<'tcx> {
         let upvar_tys = relation.relate_zip(&a.upvar_tys, &b.upvar_tys)?;
         Ok(ty::ClosureSubsts {
             func_substs: substs,
-            upvar_tys: relation.tcx().mk_type_list(upvar_tys)
+            upvar_tys: relation.tcx().mk_type_list(&upvar_tys)
         })
     }
 }
diff --git a/src/librustc/ty/structural_impls.rs b/src/librustc/ty/structural_impls.rs
index 49683c63469..0f4cff3d487 100644
--- a/src/librustc/ty/structural_impls.rs
+++ b/src/librustc/ty/structural_impls.rs
@@ -448,8 +448,8 @@ impl<'tcx> TypeFoldable<'tcx> for ty::TraitObject<'tcx> {
 
 impl<'tcx> TypeFoldable<'tcx> for &'tcx ty::Slice<Ty<'tcx>> {
     fn super_fold_with<'gcx: 'tcx, F: TypeFolder<'gcx, 'tcx>>(&self, folder: &mut F) -> Self {
-        let tys = self.iter().map(|t| t.fold_with(folder)).collect();
-        folder.tcx().mk_type_list(tys)
+        let tys = self.iter().map(|t| t.fold_with(folder)).collect::<Vec<_>>();
+        folder.tcx().mk_type_list(&tys)
     }
 
     fn super_visit_with<V: TypeVisitor<'tcx>>(&self, visitor: &mut V) -> bool {
diff --git a/src/librustc/ty/subst.rs b/src/librustc/ty/subst.rs
index e82da3c3958..b0fdaa17099 100644
--- a/src/librustc/ty/subst.rs
+++ b/src/librustc/ty/subst.rs
@@ -167,7 +167,7 @@ impl<'a, 'gcx, 'tcx> Substs<'tcx> {
     pub fn new<I>(tcx: TyCtxt<'a, 'gcx, 'tcx>, params: I)
                   -> &'tcx Substs<'tcx>
     where I: IntoIterator<Item=Kind<'tcx>> {
-        tcx.mk_substs(params.into_iter().collect())
+        tcx.mk_substs(&params.into_iter().collect::<Vec<_>>())
     }
 
     pub fn maybe_new<I, E>(tcx: TyCtxt<'a, 'gcx, 'tcx>, params: I)
@@ -311,7 +311,7 @@ impl<'tcx> TypeFoldable<'tcx> for &'tcx Substs<'tcx> {
         if params[..] == self[..] {
             self
         } else {
-            folder.tcx().mk_substs(params)
+            folder.tcx().mk_substs(&params)
         }
     }
 
diff --git a/src/librustc_driver/test.rs b/src/librustc_driver/test.rs
index f6772b87718..15be80f4ee5 100644
--- a/src/librustc_driver/test.rs
+++ b/src/librustc_driver/test.rs
@@ -275,7 +275,7 @@ impl<'a, 'gcx, 'tcx> Env<'a, 'gcx, 'tcx> {
     }
 
     pub fn t_pair(&self, ty1: Ty<'tcx>, ty2: Ty<'tcx>) -> Ty<'tcx> {
-        self.infcx.tcx.mk_tup(vec![ty1, ty2])
+        self.infcx.tcx.mk_tup(&[ty1, ty2])
     }
 
     pub fn t_param(&self, index: u32) -> Ty<'tcx> {
@@ -803,8 +803,8 @@ fn walk_ty() {
         let tcx = env.infcx.tcx;
         let int_ty = tcx.types.isize;
         let uint_ty = tcx.types.usize;
-        let tup1_ty = tcx.mk_tup(vec![int_ty, uint_ty, int_ty, uint_ty]);
-        let tup2_ty = tcx.mk_tup(vec![tup1_ty, tup1_ty, uint_ty]);
+        let tup1_ty = tcx.mk_tup(&[int_ty, uint_ty, int_ty, uint_ty]);
+        let tup2_ty = tcx.mk_tup(&[tup1_ty, tup1_ty, uint_ty]);
         let uniq_ty = tcx.mk_box(tup2_ty);
         let walked: Vec<_> = uniq_ty.walk().collect();
         assert_eq!(walked,
@@ -819,8 +819,8 @@ fn walk_ty_skip_subtree() {
         let tcx = env.infcx.tcx;
         let int_ty = tcx.types.isize;
         let uint_ty = tcx.types.usize;
-        let tup1_ty = tcx.mk_tup(vec![int_ty, uint_ty, int_ty, uint_ty]);
-        let tup2_ty = tcx.mk_tup(vec![tup1_ty, tup1_ty, uint_ty]);
+        let tup1_ty = tcx.mk_tup(&[int_ty, uint_ty, int_ty, uint_ty]);
+        let tup2_ty = tcx.mk_tup(&[tup1_ty, tup1_ty, uint_ty]);
         let uniq_ty = tcx.mk_box(tup2_ty);
 
         // types we expect to see (in order), plus a boolean saying
diff --git a/src/librustc_metadata/decoder.rs b/src/librustc_metadata/decoder.rs
index bdb4d383cee..e18fd581443 100644
--- a/src/librustc_metadata/decoder.rs
+++ b/src/librustc_metadata/decoder.rs
@@ -374,7 +374,7 @@ impl<'a, 'tcx> SpecializedDecoder<ty::GenericPredicates<'tcx>> for DecodeContext
 
 impl<'a, 'tcx> SpecializedDecoder<&'tcx Substs<'tcx>> for DecodeContext<'a, 'tcx> {
     fn specialized_decode(&mut self) -> Result<&'tcx Substs<'tcx>, Self::Error> {
-        Ok(self.tcx().mk_substs(Decodable::decode(self)?))
+        Ok(self.tcx().mk_substs(&Vec::decode(self)?))
     }
 }
 
@@ -386,7 +386,7 @@ impl<'a, 'tcx> SpecializedDecoder<&'tcx ty::Region> for DecodeContext<'a, 'tcx>
 
 impl<'a, 'tcx> SpecializedDecoder<&'tcx ty::Slice<Ty<'tcx>>> for DecodeContext<'a, 'tcx> {
     fn specialized_decode(&mut self) -> Result<&'tcx ty::Slice<Ty<'tcx>>, Self::Error> {
-        Ok(self.tcx().mk_type_list(Decodable::decode(self)?))
+        Ok(self.tcx().mk_type_list(&Vec::decode(self)?))
     }
 }
 
diff --git a/src/librustc_mir/build/expr/as_rvalue.rs b/src/librustc_mir/build/expr/as_rvalue.rs
index 9b7f3468c19..d30af8b8255 100644
--- a/src/librustc_mir/build/expr/as_rvalue.rs
+++ b/src/librustc_mir/build/expr/as_rvalue.rs
@@ -257,7 +257,7 @@ impl<'a, 'gcx, 'tcx> Builder<'a, 'gcx, 'tcx> {
         let source_info = self.source_info(span);
         let bool_ty = self.hir.bool_ty();
         if self.hir.check_overflow() && op.is_checkable() && ty.is_integral() {
-            let result_tup = self.hir.tcx().mk_tup(vec![ty, bool_ty]);
+            let result_tup = self.hir.tcx().mk_tup(&[ty, bool_ty]);
             let result_value = self.temp(result_tup);
 
             self.cfg.push_assign(block, source_info,
diff --git a/src/librustc_trans/callee.rs b/src/librustc_trans/callee.rs
index 05e22896c40..5c7ab77648e 100644
--- a/src/librustc_trans/callee.rs
+++ b/src/librustc_trans/callee.rs
@@ -327,7 +327,7 @@ fn trans_fn_pointer_shim<'a, 'tcx>(
         }
     };
     let sig = tcx.erase_late_bound_regions_and_normalize(sig);
-    let tuple_input_ty = tcx.mk_tup(sig.inputs.to_vec());
+    let tuple_input_ty = tcx.mk_tup(&sig.inputs);
     let sig = ty::FnSig {
         inputs: vec![bare_fn_ty_maybe_ref,
                      tuple_input_ty],
diff --git a/src/librustc_trans/mir/constant.rs b/src/librustc_trans/mir/constant.rs
index 76b63512bdb..baa306069f1 100644
--- a/src/librustc_trans/mir/constant.rs
+++ b/src/librustc_trans/mir/constant.rs
@@ -773,7 +773,7 @@ impl<'a, 'tcx> MirConstContext<'a, 'tcx> {
                 let rhs = self.const_operand(rhs, span)?;
                 let ty = lhs.ty;
                 let val_ty = op.ty(tcx, lhs.ty, rhs.ty);
-                let binop_ty = tcx.mk_tup(vec![val_ty, tcx.types.bool]);
+                let binop_ty = tcx.mk_tup(&[val_ty, tcx.types.bool]);
                 let (lhs, rhs) = (lhs.llval, rhs.llval);
                 assert!(!ty.is_fp());
 
diff --git a/src/librustc_trans/mir/rvalue.rs b/src/librustc_trans/mir/rvalue.rs
index 97aa475be68..5ffaadf972a 100644
--- a/src/librustc_trans/mir/rvalue.rs
+++ b/src/librustc_trans/mir/rvalue.rs
@@ -430,7 +430,7 @@ impl<'bcx, 'tcx> MirContext<'bcx, 'tcx> {
                                                              lhs.immediate(), rhs.immediate(),
                                                              lhs.ty);
                 let val_ty = op.ty(bcx.tcx(), lhs.ty, rhs.ty);
-                let operand_ty = bcx.tcx().mk_tup(vec![val_ty, bcx.tcx().types.bool]);
+                let operand_ty = bcx.tcx().mk_tup(&[val_ty, bcx.tcx().types.bool]);
                 let operand = OperandRef {
                     val: result,
                     ty: operand_ty
diff --git a/src/librustc_typeck/astconv.rs b/src/librustc_typeck/astconv.rs
index c9ce320988c..0c4e6324b89 100644
--- a/src/librustc_typeck/astconv.rs
+++ b/src/librustc_typeck/astconv.rs
@@ -660,7 +660,7 @@ impl<'o, 'gcx: 'tcx, 'tcx> AstConv<'gcx, 'tcx>+'o {
             span: output_span
         };
 
-        (self.tcx().mk_tup(inputs), output_binding)
+        (self.tcx().mk_tup(&inputs), output_binding)
     }
 
     pub fn instantiate_poly_trait_ref(&self,
@@ -1663,8 +1663,8 @@ impl<'o, 'gcx: 'tcx, 'tcx> AstConv<'gcx, 'tcx>+'o {
             hir::TyTup(ref fields) => {
                 let flds = fields.iter()
                                  .map(|t| self.ast_ty_to_ty(rscope, &t))
-                                 .collect();
-                tcx.mk_tup(flds)
+                                 .collect::<Vec<_>>();
+                tcx.mk_tup(&flds)
             }
             hir::TyBareFn(ref bf) => {
                 require_c_abi_if_variadic(tcx, &bf.decl, bf.abi, ast_ty.span);
diff --git a/src/librustc_typeck/check/_match.rs b/src/librustc_typeck/check/_match.rs
index 87729da773f..f7e590871fc 100644
--- a/src/librustc_typeck/check/_match.rs
+++ b/src/librustc_typeck/check/_match.rs
@@ -169,7 +169,7 @@ impl<'a, 'gcx, 'tcx> FnCtxt<'a, 'gcx, 'tcx> {
                 let max_len = cmp::max(expected_len, elements.len());
 
                 let element_tys: Vec<_> = (0 .. max_len).map(|_| self.next_ty_var()).collect();
-                let pat_ty = tcx.mk_tup(element_tys.clone());
+                let pat_ty = tcx.mk_tup(&element_tys);
                 self.demand_eqtype(pat.span, expected, pat_ty);
                 for (i, elem) in elements.iter().enumerate_and_adjust(max_len, ddpos) {
                     self.check_pat(elem, &element_tys[i]);
diff --git a/src/librustc_typeck/check/closure.rs b/src/librustc_typeck/check/closure.rs
index 1dbd0728bf2..7b05cd1d483 100644
--- a/src/librustc_typeck/check/closure.rs
+++ b/src/librustc_typeck/check/closure.rs
@@ -71,7 +71,7 @@ impl<'a, 'gcx, 'tcx> FnCtxt<'a, 'gcx, 'tcx> {
 
         let closure_type = self.tcx.mk_closure(expr_def_id,
                                                self.parameter_environment.free_substs,
-                                               upvar_tys);
+                                               &upvar_tys);
 
         let fn_sig = self.tcx
             .liberate_late_bound_regions(self.tcx.region_maps.call_site_extent(expr.id, body.id),
@@ -88,7 +88,7 @@ impl<'a, 'gcx, 'tcx> FnCtxt<'a, 'gcx, 'tcx> {
 
         // Tuple up the arguments and insert the resulting function type into
         // the `closures` table.
-        fn_ty.sig.0.inputs = vec![self.tcx.mk_tup(fn_ty.sig.0.inputs)];
+        fn_ty.sig.0.inputs = vec![self.tcx.mk_tup(&fn_ty.sig.0.inputs)];
 
         debug!("closure for {:?} --> sig={:?} opt_kind={:?}",
                expr_def_id,
diff --git a/src/librustc_typeck/check/intrinsic.rs b/src/librustc_typeck/check/intrinsic.rs
index 93d8b3e1563..7171b33a3af 100644
--- a/src/librustc_typeck/check/intrinsic.rs
+++ b/src/librustc_typeck/check/intrinsic.rs
@@ -89,7 +89,7 @@ pub fn check_intrinsic_type(ccx: &CrateCtxt, it: &hir::ForeignItem) {
             "cxchg" | "cxchgweak" => (1, vec!(tcx.mk_mut_ptr(param(ccx, 0)),
                                               param(ccx, 0),
                                               param(ccx, 0)),
-                                      tcx.mk_tup(vec!(param(ccx, 0), tcx.types.bool))),
+                                      tcx.mk_tup(&[param(ccx, 0), tcx.types.bool])),
             "load" => (1, vec!(tcx.mk_imm_ptr(param(ccx, 0))),
                        param(ccx, 0)),
             "store" => (1, vec!(tcx.mk_mut_ptr(param(ccx, 0)), param(ccx, 0)),
@@ -274,7 +274,7 @@ pub fn check_intrinsic_type(ccx: &CrateCtxt, it: &hir::ForeignItem) {
 
             "add_with_overflow" | "sub_with_overflow"  | "mul_with_overflow" =>
                 (1, vec!(param(ccx, 0), param(ccx, 0)),
-                tcx.mk_tup(vec!(param(ccx, 0), tcx.types.bool))),
+                tcx.mk_tup(&[param(ccx, 0), tcx.types.bool])),
 
             "unchecked_div" | "unchecked_rem" =>
                 (1, vec![param(ccx, 0), param(ccx, 0)], param(ccx, 0)),
diff --git a/src/librustc_typeck/check/mod.rs b/src/librustc_typeck/check/mod.rs
index 2224b747210..af5a1d7b713 100644
--- a/src/librustc_typeck/check/mod.rs
+++ b/src/librustc_typeck/check/mod.rs
@@ -2380,7 +2380,7 @@ impl<'a, 'gcx, 'tcx> FnCtxt<'a, 'gcx, 'tcx> {
 
             let err_inputs = match tuple_arguments {
                 DontTupleArguments => err_inputs,
-                TupleArguments => vec![self.tcx.mk_tup(err_inputs)],
+                TupleArguments => vec![self.tcx.mk_tup(&err_inputs)],
             };
 
             self.check_argument_types(sp, &err_inputs[..], &[], args_no_rcvr,
@@ -3733,11 +3733,11 @@ impl<'a, 'gcx, 'tcx> FnCtxt<'a, 'gcx, 'tcx> {
                 };
                 err_field = err_field || t.references_error();
                 t
-            }).collect();
+            }).collect::<Vec<_>>();
             if err_field {
                 tcx.types.err
             } else {
-                tcx.mk_tup(elt_ts)
+                tcx.mk_tup(&elt_ts)
             }
           }
           hir::ExprStruct(ref path, ref fields, ref base_expr) => {