Rollup merge of #60928 - TheSirC:fix/60229, r=eddyb

Changes the type `mir::Mir` into `mir::Body`

Fixes part 1 of #60229 (previously attempted in #60242).

I stumbled upon the issue and it seems that the previous attempt at solving it was not merged. This is a second try more up-to-date.

The commit should have changed comments as well.
At the time of writting, it passes the tidy and check tool.

93 files changed, 458 insertions, 447 deletions

diff --git a/src/librustc/mir/cache.rs b/src/librustc/mir/cache.rs
index 1cc927b1f72..007013f8f82 100644
--- a/src/librustc/mir/cache.rs
+++ b/src/librustc/mir/cache.rs
@@ -3,7 +3,7 @@ use rustc_data_structures::sync::{RwLock, MappedReadGuard, ReadGuard};
 use rustc_data_structures::stable_hasher::{HashStable, StableHasher,
                                            StableHasherResult};
 use crate::ich::StableHashingContext;
-use crate::mir::{Mir, BasicBlock};
+use crate::mir::{Body, BasicBlock};
 
 use crate::rustc_serialize as serialize;
 
@@ -47,7 +47,7 @@ impl Cache {
 
     pub fn predecessors(
         &self,
-        mir: &Mir<'_>
+        mir: &Body<'_>
     ) -> MappedReadGuard<'_, IndexVec<BasicBlock, Vec<BasicBlock>>> {
         if self.predecessors.borrow().is_none() {
             *self.predecessors.borrow_mut() = Some(calculate_predecessors(mir));
@@ -57,7 +57,7 @@ impl Cache {
     }
 }
 
-fn calculate_predecessors(mir: &Mir<'_>) -> IndexVec<BasicBlock, Vec<BasicBlock>> {
+fn calculate_predecessors(mir: &Body<'_>) -> IndexVec<BasicBlock, Vec<BasicBlock>> {
     let mut result = IndexVec::from_elem(vec![], mir.basic_blocks());
     for (bb, data) in mir.basic_blocks().iter_enumerated() {
         if let Some(ref term) = data.terminator {
diff --git a/src/librustc/mir/interpret/mod.rs b/src/librustc/mir/interpret/mod.rs
index 07d22cf991c..7985af914ff 100644
--- a/src/librustc/mir/interpret/mod.rs
+++ b/src/librustc/mir/interpret/mod.rs
@@ -47,7 +47,7 @@ pub struct GlobalId<'tcx> {
     /// For a promoted global, the `Instance` of the function they belong to.
     pub instance: ty::Instance<'tcx>,
 
-    /// The index for promoted globals within their function's `Mir`.
+    /// The index for promoted globals within their function's `mir::Body`.
     pub promoted: Option<mir::Promoted>,
 }
 
diff --git a/src/librustc/mir/mod.rs b/src/librustc/mir/mod.rs
index e2a8cd6b17d..a703a396b02 100644
--- a/src/librustc/mir/mod.rs
+++ b/src/librustc/mir/mod.rs
@@ -60,7 +60,7 @@ impl<'tcx> HasLocalDecls<'tcx> for LocalDecls<'tcx> {
     }
 }
 
-impl<'tcx> HasLocalDecls<'tcx> for Mir<'tcx> {
+impl<'tcx> HasLocalDecls<'tcx> for Body<'tcx> {
     fn local_decls(&self) -> &LocalDecls<'tcx> {
         &self.local_decls
     }
@@ -86,7 +86,7 @@ impl MirPhase {
 
 /// Lowered representation of a single function.
 #[derive(Clone, RustcEncodable, RustcDecodable, Debug)]
-pub struct Mir<'tcx> {
+pub struct Body<'tcx> {
     /// List of basic blocks. References to basic block use a newtyped index type `BasicBlock`
     /// that indexes into this vector.
     basic_blocks: IndexVec<BasicBlock, BasicBlockData<'tcx>>,
@@ -107,15 +107,15 @@ pub struct Mir<'tcx> {
     pub source_scope_local_data: ClearCrossCrate<IndexVec<SourceScope, SourceScopeLocalData>>,
 
     /// Rvalues promoted from this function, such as borrows of constants.
-    /// Each of them is the Mir of a constant with the fn's type parameters
+    /// Each of them is the Body of a constant with the fn's type parameters
     /// in scope, but a separate set of locals.
-    pub promoted: IndexVec<Promoted, Mir<'tcx>>,
+    pub promoted: IndexVec<Promoted, Body<'tcx>>,
 
     /// Yields type of the function, if it is a generator.
     pub yield_ty: Option<Ty<'tcx>>,
 
     /// Generator drop glue
-    pub generator_drop: Option<Box<Mir<'tcx>>>,
+    pub generator_drop: Option<Box<Body<'tcx>>>,
 
     /// The layout of a generator. Produced by the state transformation.
     pub generator_layout: Option<GeneratorLayout<'tcx>>,
@@ -167,12 +167,12 @@ pub struct Mir<'tcx> {
     cache: cache::Cache,
 }
 
-impl<'tcx> Mir<'tcx> {
+impl<'tcx> Body<'tcx> {
     pub fn new(
         basic_blocks: IndexVec<BasicBlock, BasicBlockData<'tcx>>,
         source_scopes: IndexVec<SourceScope, SourceScopeData>,
         source_scope_local_data: ClearCrossCrate<IndexVec<SourceScope, SourceScopeLocalData>>,
-        promoted: IndexVec<Promoted, Mir<'tcx>>,
+        promoted: IndexVec<Promoted, Body<'tcx>>,
         yield_ty: Option<Ty<'tcx>>,
         local_decls: LocalDecls<'tcx>,
         user_type_annotations: CanonicalUserTypeAnnotations<'tcx>,
@@ -189,7 +189,7 @@ impl<'tcx> Mir<'tcx> {
             local_decls.len()
         );
 
-        Mir {
+        Body {
             phase: MirPhase::Build,
             basic_blocks,
             source_scopes,
@@ -423,7 +423,7 @@ pub enum Safety {
     ExplicitUnsafe(hir::HirId),
 }
 
-impl_stable_hash_for!(struct Mir<'tcx> {
+impl_stable_hash_for!(struct Body<'tcx> {
     phase,
     basic_blocks,
     source_scopes,
@@ -442,7 +442,7 @@ impl_stable_hash_for!(struct Mir<'tcx> {
     cache
 });
 
-impl<'tcx> Index<BasicBlock> for Mir<'tcx> {
+impl<'tcx> Index<BasicBlock> for Body<'tcx> {
     type Output = BasicBlockData<'tcx>;
 
     #[inline]
@@ -451,7 +451,7 @@ impl<'tcx> Index<BasicBlock> for Mir<'tcx> {
     }
 }
 
-impl<'tcx> IndexMut<BasicBlock> for Mir<'tcx> {
+impl<'tcx> IndexMut<BasicBlock> for Body<'tcx> {
     #[inline]
     fn index_mut(&mut self, index: BasicBlock) -> &mut BasicBlockData<'tcx> {
         &mut self.basic_blocks_mut()[index]
@@ -599,7 +599,7 @@ newtype_index! {
     }
 }
 
-/// Classifies locals into categories. See `Mir::local_kind`.
+/// Classifies locals into categories. See `Body::local_kind`.
 #[derive(PartialEq, Eq, Debug, HashStable)]
 pub enum LocalKind {
     /// User-declared variable binding
@@ -2828,23 +2828,23 @@ impl<'tcx> Display for Constant<'tcx> {
     }
 }
 
-impl<'tcx> graph::DirectedGraph for Mir<'tcx> {
+impl<'tcx> graph::DirectedGraph for Body<'tcx> {
     type Node = BasicBlock;
 }
 
-impl<'tcx> graph::WithNumNodes for Mir<'tcx> {
+impl<'tcx> graph::WithNumNodes for Body<'tcx> {
     fn num_nodes(&self) -> usize {
         self.basic_blocks.len()
     }
 }
 
-impl<'tcx> graph::WithStartNode for Mir<'tcx> {
+impl<'tcx> graph::WithStartNode for Body<'tcx> {
     fn start_node(&self) -> Self::Node {
         START_BLOCK
     }
 }
 
-impl<'tcx> graph::WithPredecessors for Mir<'tcx> {
+impl<'tcx> graph::WithPredecessors for Body<'tcx> {
     fn predecessors<'graph>(
         &'graph self,
         node: Self::Node,
@@ -2853,7 +2853,7 @@ impl<'tcx> graph::WithPredecessors for Mir<'tcx> {
     }
 }
 
-impl<'tcx> graph::WithSuccessors for Mir<'tcx> {
+impl<'tcx> graph::WithSuccessors for Body<'tcx> {
     fn successors<'graph>(
         &'graph self,
         node: Self::Node,
@@ -2862,12 +2862,12 @@ impl<'tcx> graph::WithSuccessors for Mir<'tcx> {
     }
 }
 
-impl<'a, 'b> graph::GraphPredecessors<'b> for Mir<'a> {
+impl<'a, 'b> graph::GraphPredecessors<'b> for Body<'a> {
     type Item = BasicBlock;
     type Iter = IntoIter<BasicBlock>;
 }
 
-impl<'a, 'b> graph::GraphSuccessors<'b> for Mir<'a> {
+impl<'a, 'b> graph::GraphSuccessors<'b> for Body<'a> {
     type Item = BasicBlock;
     type Iter = iter::Cloned<Successors<'b>>;
 }
@@ -2906,7 +2906,7 @@ impl Location {
     }
 
     /// Returns `true` if `other` is earlier in the control flow graph than `self`.
-    pub fn is_predecessor_of<'tcx>(&self, other: Location, mir: &Mir<'tcx>) -> bool {
+    pub fn is_predecessor_of<'tcx>(&self, other: Location, mir: &Body<'tcx>) -> bool {
         // If we are in the same block as the other location and are an earlier statement
         // then we are a predecessor of `other`.
         if self.block == other.block && self.statement_index < other.statement_index {
@@ -3159,7 +3159,7 @@ CloneTypeFoldableAndLiftImpls! {
 }
 
 BraceStructTypeFoldableImpl! {
-    impl<'tcx> TypeFoldable<'tcx> for Mir<'tcx> {
+    impl<'tcx> TypeFoldable<'tcx> for Body<'tcx> {
         phase,
         basic_blocks,
         source_scopes,
diff --git a/src/librustc/mir/traversal.rs b/src/librustc/mir/traversal.rs
index f8398c27cc2..75d995d801d 100644
--- a/src/librustc/mir/traversal.rs
+++ b/src/librustc/mir/traversal.rs
@@ -21,14 +21,14 @@ use super::*;
 /// A preorder traversal of this graph is either `A B D C` or `A C D B`
 #[derive(Clone)]
 pub struct Preorder<'a, 'tcx: 'a> {
-    mir: &'a Mir<'tcx>,
+    mir: &'a Body<'tcx>,
     visited: BitSet<BasicBlock>,
     worklist: Vec<BasicBlock>,
     root_is_start_block: bool,
 }
 
 impl<'a, 'tcx> Preorder<'a, 'tcx> {
-    pub fn new(mir: &'a Mir<'tcx>, root: BasicBlock) -> Preorder<'a, 'tcx> {
+    pub fn new(mir: &'a Body<'tcx>, root: BasicBlock) -> Preorder<'a, 'tcx> {
         let worklist = vec![root];
 
         Preorder {
@@ -40,7 +40,7 @@ impl<'a, 'tcx> Preorder<'a, 'tcx> {
     }
 }
 
-pub fn preorder<'a, 'tcx>(mir: &'a Mir<'tcx>) -> Preorder<'a, 'tcx> {
+pub fn preorder<'a, 'tcx>(mir: &'a Body<'tcx>) -> Preorder<'a, 'tcx> {
     Preorder::new(mir, START_BLOCK)
 }
 
@@ -99,14 +99,14 @@ impl<'a, 'tcx> Iterator for Preorder<'a, 'tcx> {
 ///
 /// A Postorder traversal of this graph is `D B C A` or `D C B A`
 pub struct Postorder<'a, 'tcx: 'a> {
-    mir: &'a Mir<'tcx>,
+    mir: &'a Body<'tcx>,
     visited: BitSet<BasicBlock>,
     visit_stack: Vec<(BasicBlock, Successors<'a>)>,
     root_is_start_block: bool,
 }
 
 impl<'a, 'tcx> Postorder<'a, 'tcx> {
-    pub fn new(mir: &'a Mir<'tcx>, root: BasicBlock) -> Postorder<'a, 'tcx> {
+    pub fn new(mir: &'a Body<'tcx>, root: BasicBlock) -> Postorder<'a, 'tcx> {
         let mut po = Postorder {
             mir,
             visited: BitSet::new_empty(mir.basic_blocks().len()),
@@ -194,7 +194,7 @@ impl<'a, 'tcx> Postorder<'a, 'tcx> {
     }
 }
 
-pub fn postorder<'a, 'tcx>(mir: &'a Mir<'tcx>) -> Postorder<'a, 'tcx> {
+pub fn postorder<'a, 'tcx>(mir: &'a Body<'tcx>) -> Postorder<'a, 'tcx> {
     Postorder::new(mir, START_BLOCK)
 }
 
@@ -252,13 +252,13 @@ impl<'a, 'tcx> Iterator for Postorder<'a, 'tcx> {
 /// to re-use the traversal
 #[derive(Clone)]
 pub struct ReversePostorder<'a, 'tcx: 'a> {
-    mir: &'a Mir<'tcx>,
+    mir: &'a Body<'tcx>,
     blocks: Vec<BasicBlock>,
     idx: usize
 }
 
 impl<'a, 'tcx> ReversePostorder<'a, 'tcx> {
-    pub fn new(mir: &'a Mir<'tcx>, root: BasicBlock) -> ReversePostorder<'a, 'tcx> {
+    pub fn new(mir: &'a Body<'tcx>, root: BasicBlock) -> ReversePostorder<'a, 'tcx> {
         let blocks : Vec<_> = Postorder::new(mir, root).map(|(bb, _)| bb).collect();
 
         let len = blocks.len();
@@ -276,7 +276,7 @@ impl<'a, 'tcx> ReversePostorder<'a, 'tcx> {
 }
 
 
-pub fn reverse_postorder<'a, 'tcx>(mir: &'a Mir<'tcx>) -> ReversePostorder<'a, 'tcx> {
+pub fn reverse_postorder<'a, 'tcx>(mir: &'a Body<'tcx>) -> ReversePostorder<'a, 'tcx> {
     ReversePostorder::new(mir, START_BLOCK)
 }
 
diff --git a/src/librustc/mir/visit.rs b/src/librustc/mir/visit.rs
index 64ffd80e21e..dd33fae0d61 100644
--- a/src/librustc/mir/visit.rs
+++ b/src/librustc/mir/visit.rs
@@ -71,8 +71,8 @@ macro_rules! make_mir_visitor {
             // Override these, and call `self.super_xxx` to revert back to the
             // default behavior.
 
-            fn visit_mir(&mut self, mir: & $($mutability)? Mir<'tcx>) {
-                self.super_mir(mir);
+            fn visit_body(&mut self, mir: & $($mutability)? Body<'tcx>) {
+                self.super_body(mir);
             }
 
             fn visit_basic_block_data(&mut self,
@@ -251,8 +251,8 @@ macro_rules! make_mir_visitor {
             // The `super_xxx` methods comprise the default behavior and are
             // not meant to be overridden.
 
-            fn super_mir(&mut self,
-                         mir: & $($mutability)? Mir<'tcx>) {
+            fn super_body(&mut self,
+                         mir: & $($mutability)? Body<'tcx>) {
                 if let Some(yield_ty) = &$($mutability)? mir.yield_ty {
                     self.visit_ty(yield_ty, TyContext::YieldTy(SourceInfo {
                         span: mir.span,
@@ -261,7 +261,7 @@ macro_rules! make_mir_visitor {
                 }
 
                 // for best performance, we want to use an iterator rather
-                // than a for-loop, to avoid calling Mir::invalidate for
+                // than a for-loop, to avoid calling `mir::Body::invalidate` for
                 // each basic block.
                 macro_rules! basic_blocks {
                     (mut) => (mir.basic_blocks_mut().iter_enumerated_mut());
@@ -825,7 +825,7 @@ macro_rules! make_mir_visitor {
 
             // Convenience methods
 
-            fn visit_location(&mut self, mir: & $($mutability)? Mir<'tcx>, location: Location) {
+            fn visit_location(&mut self, mir: & $($mutability)? Body<'tcx>, location: Location) {
                 let basic_block = & $($mutability)? mir[location.block];
                 if basic_block.statements.len() == location.statement_index {
                     if let Some(ref $($mutability)? terminator) = basic_block.terminator {
diff --git a/src/librustc/query/mod.rs b/src/librustc/query/mod.rs
index ed363800d79..81aa8d434d3 100644
--- a/src/librustc/query/mod.rs
+++ b/src/librustc/query/mod.rs
@@ -88,7 +88,7 @@ rustc_queries! {
             desc { "getting a list of all mir_keys" }
         }
 
-        /// Maps DefId's that have an associated Mir to the result
+        /// Maps DefId's that have an associated `mir::Body` to the result
         /// of the MIR qualify_consts pass. The actual meaning of
         /// the value isn't known except to the pass itself.
         query mir_const_qualif(key: DefId) -> (u8, &'tcx BitSet<mir::Local>) {
@@ -97,26 +97,26 @@ rustc_queries! {
 
         /// Fetch the MIR for a given `DefId` right after it's built - this includes
         /// unreachable code.
-        query mir_built(_: DefId) -> &'tcx Steal<mir::Mir<'tcx>> {}
+        query mir_built(_: DefId) -> &'tcx Steal<mir::Body<'tcx>> {}
 
         /// Fetch the MIR for a given `DefId` up till the point where it is
         /// ready for const evaluation.
         ///
         /// See the README for the `mir` module for details.
-        query mir_const(_: DefId) -> &'tcx Steal<mir::Mir<'tcx>> {
+        query mir_const(_: DefId) -> &'tcx Steal<mir::Body<'tcx>> {
             no_hash
         }
 
-        query mir_validated(_: DefId) -> &'tcx Steal<mir::Mir<'tcx>> {
+        query mir_validated(_: DefId) -> &'tcx Steal<mir::Body<'tcx>> {
             no_hash
         }
 
         /// MIR after our optimization passes have run. This is MIR that is ready
         /// for codegen. This is also the only query that can fetch non-local MIR, at present.
-        query optimized_mir(key: DefId) -> &'tcx mir::Mir<'tcx> {
+        query optimized_mir(key: DefId) -> &'tcx mir::Body<'tcx> {
             cache { key.is_local() }
             load_cached(tcx, id) {
-                let mir: Option<crate::mir::Mir<'tcx>> = tcx.queries.on_disk_cache
+                let mir: Option<crate::mir::Body<'tcx>> = tcx.queries.on_disk_cache
                                                             .try_load_query_result(tcx, id);
                 mir.map(|x| tcx.alloc_mir(x))
             }
@@ -456,7 +456,7 @@ rustc_queries! {
         /// in the case of closures, this will be redirected to the enclosing function.
         query region_scope_tree(_: DefId) -> &'tcx region::ScopeTree {}
 
-        query mir_shims(key: ty::InstanceDef<'tcx>) -> &'tcx mir::Mir<'tcx> {
+        query mir_shims(key: ty::InstanceDef<'tcx>) -> &'tcx mir::Body<'tcx> {
             no_force
             desc { |tcx| "generating MIR shim for `{}`", tcx.def_path_str(key.def_id()) }
         }
diff --git a/src/librustc/ty/context.rs b/src/librustc/ty/context.rs
index 92de3e28d19..ff218911ffb 100644
--- a/src/librustc/ty/context.rs
+++ b/src/librustc/ty/context.rs
@@ -23,7 +23,7 @@ use crate::middle::cstore::EncodedMetadata;
 use crate::middle::lang_items;
 use crate::middle::resolve_lifetime::{self, ObjectLifetimeDefault};
 use crate::middle::stability;
-use crate::mir::{self, Mir, interpret, ProjectionKind};
+use crate::mir::{self, Body, interpret, ProjectionKind};
 use crate::mir::interpret::{ConstValue, Allocation, Scalar};
 use crate::ty::subst::{Kind, InternalSubsts, SubstsRef, Subst};
 use crate::ty::ReprOptions;
@@ -103,8 +103,8 @@ pub struct GlobalArenas<'tcx> {
     generics: TypedArena<ty::Generics>,
     trait_def: TypedArena<ty::TraitDef>,
     adt_def: TypedArena<ty::AdtDef>,
-    steal_mir: TypedArena<Steal<Mir<'tcx>>>,
-    mir: TypedArena<Mir<'tcx>>,
+    steal_mir: TypedArena<Steal<Body<'tcx>>>,
+    mir: TypedArena<Body<'tcx>>,
     tables: TypedArena<ty::TypeckTables<'tcx>>,
     /// miri allocations
     const_allocs: TypedArena<interpret::Allocation>,
@@ -1154,11 +1154,11 @@ impl<'a, 'gcx, 'tcx> TyCtxt<'a, 'gcx, 'tcx> {
         self.global_arenas.generics.alloc(generics)
     }
 
-    pub fn alloc_steal_mir(self, mir: Mir<'gcx>) -> &'gcx Steal<Mir<'gcx>> {
+    pub fn alloc_steal_mir(self, mir: Body<'gcx>) -> &'gcx Steal<Body<'gcx>> {
         self.global_arenas.steal_mir.alloc(Steal::new(mir))
     }
 
-    pub fn alloc_mir(self, mir: Mir<'gcx>) -> &'gcx Mir<'gcx> {
+    pub fn alloc_mir(self, mir: Body<'gcx>) -> &'gcx Body<'gcx> {
         self.global_arenas.mir.alloc(mir)
     }
 
diff --git a/src/librustc/ty/mod.rs b/src/librustc/ty/mod.rs
index f1d1abfa0fb..fa993325e27 100644
--- a/src/librustc/ty/mod.rs
+++ b/src/librustc/ty/mod.rs
@@ -19,7 +19,7 @@ use crate::ich::StableHashingContext;
 use crate::infer::canonical::Canonical;
 use crate::middle::lang_items::{FnTraitLangItem, FnMutTraitLangItem, FnOnceTraitLangItem};
 use crate::middle::resolve_lifetime::ObjectLifetimeDefault;
-use crate::mir::Mir;
+use crate::mir::Body;
 use crate::mir::interpret::{GlobalId, ErrorHandled};
 use crate::mir::GeneratorLayout;
 use crate::session::CrateDisambiguator;
@@ -3002,7 +3002,7 @@ impl<'a, 'gcx, 'tcx> TyCtxt<'a, 'gcx, 'tcx> {
 
     /// Returns the possibly-auto-generated MIR of a `(DefId, Subst)` pair.
     pub fn instance_mir(self, instance: ty::InstanceDef<'gcx>)
-                        -> &'gcx Mir<'gcx>
+                        -> &'gcx Body<'gcx>
     {
         match instance {
             ty::InstanceDef::Item(did) => {
diff --git a/src/librustc/ty/steal.rs b/src/librustc/ty/steal.rs
index a8f9301ba51..711e59dbcc9 100644
--- a/src/librustc/ty/steal.rs
+++ b/src/librustc/ty/steal.rs
@@ -7,9 +7,9 @@ use rustc_data_structures::sync::{RwLock, ReadGuard, MappedReadGuard};
 /// optimization, but that'd be expensive. And yet we don't just want
 /// to mutate it in place, because that would spoil the idea that
 /// queries are these pure functions that produce an immutable value
-/// (since if you did the query twice, you could observe the
-/// mutations). So instead we have the query produce a `&'tcx
-/// Steal<Mir<'tcx>>` (to be very specific). Now we can read from this
+/// (since if you did the query twice, you could observe the mutations).
+/// So instead we have the query produce a `&'tcx Steal<mir::Body<'tcx>>`
+/// (to be very specific). Now we can read from this
 /// as much as we want (using `borrow()`), but you can also
 /// `steal()`. Once you steal, any further attempt to read will panic.
 /// Therefore, we know that -- assuming no ICE -- nobody is observing
diff --git a/src/librustc_codegen_llvm/debuginfo/create_scope_map.rs b/src/librustc_codegen_llvm/debuginfo/create_scope_map.rs
index c8ddf733ecf..8b3ed5b0c62 100644
--- a/src/librustc_codegen_llvm/debuginfo/create_scope_map.rs
+++ b/src/librustc_codegen_llvm/debuginfo/create_scope_map.rs
@@ -5,7 +5,7 @@ use super::utils::{DIB, span_start};
 use crate::llvm;
 use crate::llvm::debuginfo::{DIScope, DISubprogram};
 use crate::common::CodegenCx;
-use rustc::mir::{Mir, SourceScope};
+use rustc::mir::{Body, SourceScope};
 
 use libc::c_uint;
 
@@ -20,7 +20,7 @@ use syntax_pos::BytePos;
 /// If debuginfo is disabled, the returned vector is empty.
 pub fn create_mir_scopes(
     cx: &CodegenCx<'ll, '_>,
-    mir: &Mir<'_>,
+    mir: &Body<'_>,
     debug_context: &FunctionDebugContext<&'ll DISubprogram>,
 ) -> IndexVec<SourceScope, MirDebugScope<&'ll DIScope>> {
     let null_scope = MirDebugScope {
@@ -55,7 +55,7 @@ pub fn create_mir_scopes(
 }
 
 fn make_mir_scope(cx: &CodegenCx<'ll, '_>,
-                  mir: &Mir<'_>,
+                  mir: &Body<'_>,
                   has_variables: &BitSet<SourceScope>,
                   debug_context: &FunctionDebugContextData<&'ll DISubprogram>,
                   scope: SourceScope,
diff --git a/src/librustc_codegen_llvm/debuginfo/mod.rs b/src/librustc_codegen_llvm/debuginfo/mod.rs
index 527290392ff..6fa594d4453 100644
--- a/src/librustc_codegen_llvm/debuginfo/mod.rs
+++ b/src/librustc_codegen_llvm/debuginfo/mod.rs
@@ -239,7 +239,7 @@ impl DebugInfoMethods<'tcx> for CodegenCx<'ll, 'tcx> {
         instance: Instance<'tcx>,
         sig: ty::FnSig<'tcx>,
         llfn: &'ll Value,
-        mir: &mir::Mir<'_>,
+        mir: &mir::Body<'_>,
     ) -> FunctionDebugContext<&'ll DISubprogram> {
         if self.sess().opts.debuginfo == DebugInfo::None {
             return FunctionDebugContext::DebugInfoDisabled;
@@ -523,7 +523,7 @@ impl DebugInfoMethods<'tcx> for CodegenCx<'ll, 'tcx> {
 
     fn create_mir_scopes(
         &self,
-        mir: &mir::Mir<'_>,
+        mir: &mir::Body<'_>,
         debug_context: &mut FunctionDebugContext<&'ll DISubprogram>,
     ) -> IndexVec<mir::SourceScope, MirDebugScope<&'ll DIScope>> {
         create_scope_map::create_mir_scopes(self, mir, debug_context)
diff --git a/src/librustc_codegen_ssa/mir/analyze.rs b/src/librustc_codegen_ssa/mir/analyze.rs
index 06d7b6c78f1..bb6a13ed15a 100644
--- a/src/librustc_codegen_ssa/mir/analyze.rs
+++ b/src/librustc_codegen_ssa/mir/analyze.rs
@@ -18,7 +18,7 @@ pub fn non_ssa_locals<'a, 'tcx: 'a, Bx: BuilderMethods<'a, 'tcx>>(
     let mir = fx.mir;
     let mut analyzer = LocalAnalyzer::new(fx);
 
-    analyzer.visit_mir(mir);
+    analyzer.visit_body(mir);
 
     for (index, ty) in mir.local_decls.iter().map(|l| l.ty).enumerate() {
         let ty = fx.monomorphize(&ty);
@@ -272,9 +272,9 @@ impl CleanupKind {
     }
 }
 
-pub fn cleanup_kinds<'a, 'tcx>(mir: &mir::Mir<'tcx>) -> IndexVec<mir::BasicBlock, CleanupKind> {
+pub fn cleanup_kinds<'a, 'tcx>(mir: &mir::Body<'tcx>) -> IndexVec<mir::BasicBlock, CleanupKind> {
     fn discover_masters<'tcx>(result: &mut IndexVec<mir::BasicBlock, CleanupKind>,
-                              mir: &mir::Mir<'tcx>) {
+                              mir: &mir::Body<'tcx>) {
         for (bb, data) in mir.basic_blocks().iter_enumerated() {
             match data.terminator().kind {
                 TerminatorKind::Goto { .. } |
@@ -304,7 +304,7 @@ pub fn cleanup_kinds<'a, 'tcx>(mir: &mir::Mir<'tcx>) -> IndexVec<mir::BasicBlock
     }
 
     fn propagate<'tcx>(result: &mut IndexVec<mir::BasicBlock, CleanupKind>,
-                       mir: &mir::Mir<'tcx>) {
+                       mir: &mir::Body<'tcx>) {
         let mut funclet_succs = IndexVec::from_elem(None, mir.basic_blocks());
 
         let mut set_successor = |funclet: mir::BasicBlock, succ| {
diff --git a/src/librustc_codegen_ssa/mir/mod.rs b/src/librustc_codegen_ssa/mir/mod.rs
index fed12c9a29f..4a43201dedf 100644
--- a/src/librustc_codegen_ssa/mir/mod.rs
+++ b/src/librustc_codegen_ssa/mir/mod.rs
@@ -1,6 +1,6 @@
 use rustc::ty::{self, Ty, TypeFoldable, UpvarSubsts};
 use rustc::ty::layout::{TyLayout, HasTyCtxt, FnTypeExt};
-use rustc::mir::{self, Mir};
+use rustc::mir::{self, Body};
 use rustc::session::config::DebugInfo;
 use rustc_mir::monomorphize::Instance;
 use rustc_target::abi::call::{FnType, PassMode, IgnoreMode};
@@ -27,7 +27,7 @@ use self::operand::{OperandRef, OperandValue};
 pub struct FunctionCx<'a, 'tcx: 'a, Bx: BuilderMethods<'a, 'tcx>> {
     instance: Instance<'tcx>,
 
-    mir: &'a mir::Mir<'tcx>,
+    mir: &'a mir::Body<'tcx>,
 
     debug_context: FunctionDebugContext<Bx::DIScope>,
 
@@ -196,7 +196,7 @@ impl<'a, 'tcx: 'a, V: CodegenObject> LocalRef<'tcx, V> {
 pub fn codegen_mir<'a, 'tcx: 'a, Bx: BuilderMethods<'a, 'tcx>>(
     cx: &'a Bx::CodegenCx,
     llfn: Bx::Value,
-    mir: &'a Mir<'tcx>,
+    mir: &'a Body<'tcx>,
     instance: Instance<'tcx>,
     sig: ty::FnSig<'tcx>,
 ) {
@@ -360,7 +360,7 @@ pub fn codegen_mir<'a, 'tcx: 'a, Bx: BuilderMethods<'a, 'tcx>>(
 }
 
 fn create_funclets<'a, 'tcx: 'a, Bx: BuilderMethods<'a, 'tcx>>(
-    mir: &'a Mir<'tcx>,
+    mir: &'a Body<'tcx>,
     bx: &mut Bx,
     cleanup_kinds: &IndexVec<mir::BasicBlock, CleanupKind>,
     block_bxs: &IndexVec<mir::BasicBlock, Bx::BasicBlock>)
diff --git a/src/librustc_codegen_ssa/traits/debuginfo.rs b/src/librustc_codegen_ssa/traits/debuginfo.rs
index aadffc5932b..37b7a15e2ba 100644
--- a/src/librustc_codegen_ssa/traits/debuginfo.rs
+++ b/src/librustc_codegen_ssa/traits/debuginfo.rs
@@ -22,12 +22,12 @@ pub trait DebugInfoMethods<'tcx>: BackendTypes {
         instance: Instance<'tcx>,
         sig: ty::FnSig<'tcx>,
         llfn: Self::Value,
-        mir: &mir::Mir<'_>,
+        mir: &mir::Body<'_>,
     ) -> FunctionDebugContext<Self::DIScope>;
 
     fn create_mir_scopes(
         &self,
-        mir: &mir::Mir<'_>,
+        mir: &mir::Body<'_>,
         debug_context: &mut FunctionDebugContext<Self::DIScope>,
     ) -> IndexVec<mir::SourceScope, MirDebugScope<Self::DIScope>>;
     fn extend_scope_to_file(
diff --git a/src/librustc_metadata/decoder.rs b/src/librustc_metadata/decoder.rs
index a484928ce6c..10ff606b013 100644
--- a/src/librustc_metadata/decoder.rs
+++ b/src/librustc_metadata/decoder.rs
@@ -18,7 +18,7 @@ use rustc::mir::interpret::AllocDecodingSession;
 use rustc::session::Session;
 use rustc::ty::{self, Ty, TyCtxt};
 use rustc::ty::codec::TyDecoder;
-use rustc::mir::Mir;
+use rustc::mir::Body;
 use rustc::util::captures::Captures;
 
 use std::io;
@@ -887,7 +887,7 @@ impl<'a, 'tcx> CrateMetadata {
     pub fn maybe_get_optimized_mir(&self,
                                    tcx: TyCtxt<'a, 'tcx, 'tcx>,
                                    id: DefIndex)
-                                   -> Option<Mir<'tcx>> {
+                                   -> Option<Body<'tcx>> {
         match self.is_proc_macro(id) {
             true => None,
             false => self.entry(id).mir.map(|mir| mir.decode((self, tcx))),
diff --git a/src/librustc_metadata/encoder.rs b/src/librustc_metadata/encoder.rs
index 5d080de2645..588682a2420 100644
--- a/src/librustc_metadata/encoder.rs
+++ b/src/librustc_metadata/encoder.rs
@@ -1026,7 +1026,7 @@ impl EncodeContext<'_, 'tcx> {
         self.lazy_seq(param_names.iter().map(|ident| ident.name))
     }
 
-    fn encode_optimized_mir(&mut self, def_id: DefId) -> Option<Lazy<mir::Mir<'tcx>>> {
+    fn encode_optimized_mir(&mut self, def_id: DefId) -> Option<Lazy<mir::Body<'tcx>>> {
         debug!("EntryBuilder::encode_mir({:?})", def_id);
         if self.tcx.mir_keys(LOCAL_CRATE).contains(&def_id) {
             let mir = self.tcx.optimized_mir(def_id);
diff --git a/src/librustc_metadata/schema.rs b/src/librustc_metadata/schema.rs
index b9e5bdef27a..2c3291a41d3 100644
--- a/src/librustc_metadata/schema.rs
+++ b/src/librustc_metadata/schema.rs
@@ -222,7 +222,7 @@ pub struct Entry<'tcx> {
     pub predicates: Option<Lazy<ty::GenericPredicates<'tcx>>>,
     pub predicates_defined_on: Option<Lazy<ty::GenericPredicates<'tcx>>>,
 
-    pub mir: Option<Lazy<mir::Mir<'tcx>>>,
+    pub mir: Option<Lazy<mir::Body<'tcx>>>,
 }
 
 #[derive(Copy, Clone, RustcEncodable, RustcDecodable)]
diff --git a/src/librustc_mir/borrow_check/borrow_set.rs b/src/librustc_mir/borrow_check/borrow_set.rs
index 5ced497baa1..d9d6fe0affb 100644
--- a/src/librustc_mir/borrow_check/borrow_set.rs
+++ b/src/librustc_mir/borrow_check/borrow_set.rs
@@ -5,7 +5,7 @@ use crate::dataflow::indexes::BorrowIndex;
 use crate::dataflow::move_paths::MoveData;
 use rustc::mir::traversal;
 use rustc::mir::visit::{PlaceContext, Visitor, NonUseContext, MutatingUseContext};
-use rustc::mir::{self, Location, Mir, Local};
+use rustc::mir::{self, Location, Body, Local};
 use rustc::ty::{RegionVid, TyCtxt};
 use rustc::util::nodemap::{FxHashMap, FxHashSet};
 use rustc_data_structures::indexed_vec::IndexVec;
@@ -90,7 +90,7 @@ crate enum LocalsStateAtExit {
 impl LocalsStateAtExit {
     fn build(
         locals_are_invalidated_at_exit: bool,
-        mir: &Mir<'tcx>,
+        mir: &Body<'tcx>,
         move_data: &MoveData<'tcx>
     ) -> Self {
         struct HasStorageDead(BitSet<Local>);
@@ -107,7 +107,7 @@ impl LocalsStateAtExit {
             LocalsStateAtExit::AllAreInvalidated
         } else {
             let mut has_storage_dead = HasStorageDead(BitSet::new_empty(mir.local_decls.len()));
-            has_storage_dead.visit_mir(mir);
+            has_storage_dead.visit_body(mir);
             let mut has_storage_dead_or_moved = has_storage_dead.0;
             for move_out in &move_data.moves {
                 if let Some(index) = move_data.base_local(move_out.path) {
@@ -123,7 +123,7 @@ impl LocalsStateAtExit {
 impl<'tcx> BorrowSet<'tcx> {
     pub fn build(
         tcx: TyCtxt<'_, '_, 'tcx>,
-        mir: &Mir<'tcx>,
+        mir: &Body<'tcx>,
         locals_are_invalidated_at_exit: bool,
         move_data: &MoveData<'tcx>
     ) -> Self {
@@ -163,7 +163,7 @@ impl<'tcx> BorrowSet<'tcx> {
 
 struct GatherBorrows<'a, 'gcx: 'tcx, 'tcx: 'a> {
     tcx: TyCtxt<'a, 'gcx, 'tcx>,
-    mir: &'a Mir<'tcx>,
+    mir: &'a Body<'tcx>,
     idx_vec: IndexVec<BorrowIndex, BorrowData<'tcx>>,
     location_map: FxHashMap<Location, BorrowIndex>,
     activation_map: FxHashMap<Location, Vec<BorrowIndex>>,
diff --git a/src/librustc_mir/borrow_check/location.rs b/src/librustc_mir/borrow_check/location.rs
index 20a477576c9..feade0d2a4a 100644
--- a/src/librustc_mir/borrow_check/location.rs
+++ b/src/librustc_mir/borrow_check/location.rs
@@ -1,4 +1,4 @@
-use rustc::mir::{BasicBlock, Location, Mir};
+use rustc::mir::{BasicBlock, Location, Body};
 use rustc_data_structures::indexed_vec::{Idx, IndexVec};
 
 /// Maps between a MIR Location, which identifies a particular
@@ -30,7 +30,7 @@ crate enum RichLocation {
 }
 
 impl LocationTable {
-    crate fn new(mir: &Mir<'_>) -> Self {
+    crate fn new(mir: &Body<'_>) -> Self {
         let mut num_points = 0;
         let statements_before_block = mir.basic_blocks()
             .iter()
diff --git a/src/librustc_mir/borrow_check/mod.rs b/src/librustc_mir/borrow_check/mod.rs
index 437f95e332a..82be2405701 100644
--- a/src/librustc_mir/borrow_check/mod.rs
+++ b/src/librustc_mir/borrow_check/mod.rs
@@ -10,7 +10,9 @@ use rustc::lint::builtin::{MUTABLE_BORROW_RESERVATION_CONFLICT};
 use rustc::middle::borrowck::SignalledError;
 use rustc::mir::{AggregateKind, BasicBlock, BorrowCheckResult, BorrowKind};
 use rustc::mir::{
-    ClearCrossCrate, Local, Location, Mir, Mutability, Operand, Place, PlaceBase, Static, StaticKind
+    ClearCrossCrate, Local, Location, Body, Mutability, Operand, Place, PlaceBase, Static,
+
+    StaticKind
 };
 use rustc::mir::{Field, Projection, ProjectionElem, Rvalue, Statement, StatementKind};
 use rustc::mir::{Terminator, TerminatorKind};
@@ -118,7 +120,7 @@ fn mir_borrowck<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>, def_id: DefId) -> BorrowC
     }
 
     let opt_closure_req = tcx.infer_ctxt().enter(|infcx| {
-        let input_mir: &Mir<'_> = &input_mir.borrow();
+        let input_mir: &Body<'_> = &input_mir.borrow();
         do_mir_borrowck(&infcx, input_mir, def_id)
     });
     debug!("mir_borrowck done");
@@ -128,7 +130,7 @@ fn mir_borrowck<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>, def_id: DefId) -> BorrowC
 
 fn do_mir_borrowck<'a, 'gcx, 'tcx>(
     infcx: &InferCtxt<'a, 'gcx, 'tcx>,
-    input_mir: &Mir<'gcx>,
+    input_mir: &Body<'gcx>,
     def_id: DefId,
 ) -> BorrowCheckResult<'gcx> {
     debug!("do_mir_borrowck(def_id = {:?})", def_id);
@@ -175,7 +177,7 @@ fn do_mir_borrowck<'a, 'gcx, 'tcx>(
     // requires first making our own copy of the MIR. This copy will
     // be modified (in place) to contain non-lexical lifetimes. It
     // will have a lifetime tied to the inference context.
-    let mut mir: Mir<'tcx> = input_mir.clone();
+    let mut mir: Body<'tcx> = input_mir.clone();
     let free_regions = nll::replace_regions_in_mir(infcx, def_id, param_env, &mut mir);
     let mir = &mir; // no further changes
     let location_table = &LocationTable::new(mir);
@@ -451,7 +453,7 @@ fn downgrade_if_error(diag: &mut Diagnostic) {
 
 pub struct MirBorrowckCtxt<'cx, 'gcx: 'tcx, 'tcx: 'cx> {
     infcx: &'cx InferCtxt<'cx, 'gcx, 'tcx>,
-    mir: &'cx Mir<'tcx>,
+    mir: &'cx Body<'tcx>,
     mir_def_id: DefId,
     move_data: &'cx MoveData<'tcx>,
 
@@ -537,7 +539,7 @@ pub struct MirBorrowckCtxt<'cx, 'gcx: 'tcx, 'tcx: 'cx> {
 impl<'cx, 'gcx, 'tcx> DataflowResultsConsumer<'cx, 'tcx> for MirBorrowckCtxt<'cx, 'gcx, 'tcx> {
     type FlowState = Flows<'cx, 'gcx, 'tcx>;
 
-    fn mir(&self) -> &'cx Mir<'tcx> {
+    fn mir(&self) -> &'cx Body<'tcx> {
         self.mir
     }
 
diff --git a/src/librustc_mir/borrow_check/mutability_errors.rs b/src/librustc_mir/borrow_check/mutability_errors.rs
index 16fbc8d6bb2..a292115707d 100644
--- a/src/librustc_mir/borrow_check/mutability_errors.rs
+++ b/src/librustc_mir/borrow_check/mutability_errors.rs
@@ -1,6 +1,6 @@
 use rustc::hir;
 use rustc::hir::Node;
-use rustc::mir::{self, BindingForm, Constant, ClearCrossCrate, Local, Location, Mir};
+use rustc::mir::{self, BindingForm, Constant, ClearCrossCrate, Local, Location, Body};
 use rustc::mir::{
     Mutability, Operand, Place, PlaceBase, Projection, ProjectionElem, Static, StaticKind,
 };
@@ -562,7 +562,7 @@ fn suggest_ampmut_self<'cx, 'gcx, 'tcx>(
 // by trying (3.), then (2.) and finally falling back on (1.).
 fn suggest_ampmut<'cx, 'gcx, 'tcx>(
     tcx: TyCtxt<'cx, 'gcx, 'tcx>,
-    mir: &Mir<'tcx>,
+    mir: &Body<'tcx>,
     local: Local,
     local_decl: &mir::LocalDecl<'tcx>,
     opt_ty_info: Option<Span>,
diff --git a/src/librustc_mir/borrow_check/nll/constraint_generation.rs b/src/librustc_mir/borrow_check/nll/constraint_generation.rs
index b0e395cbbdf..b485f37b78c 100644
--- a/src/librustc_mir/borrow_check/nll/constraint_generation.rs
+++ b/src/librustc_mir/borrow_check/nll/constraint_generation.rs
@@ -6,7 +6,7 @@ use crate::borrow_check::nll::region_infer::values::LivenessValues;
 use rustc::infer::InferCtxt;
 use rustc::mir::visit::TyContext;
 use rustc::mir::visit::Visitor;
-use rustc::mir::{BasicBlock, BasicBlockData, Location, Mir, Place, PlaceBase, Rvalue};
+use rustc::mir::{BasicBlock, BasicBlockData, Location, Body, Place, PlaceBase, Rvalue};
 use rustc::mir::{SourceInfo, Statement, Terminator};
 use rustc::mir::UserTypeProjection;
 use rustc::ty::fold::TypeFoldable;
@@ -18,7 +18,7 @@ pub(super) fn generate_constraints<'cx, 'gcx, 'tcx>(
     liveness_constraints: &mut LivenessValues<RegionVid>,
     all_facts: &mut Option<AllFacts>,
     location_table: &LocationTable,
-    mir: &Mir<'tcx>,
+    mir: &Body<'tcx>,
     borrow_set: &BorrowSet<'tcx>,
 ) {
     let mut cg = ConstraintGeneration {
diff --git a/src/librustc_mir/borrow_check/nll/explain_borrow/find_use.rs b/src/librustc_mir/borrow_check/nll/explain_borrow/find_use.rs
index 9a2090d0508..3921246b06d 100644
--- a/src/librustc_mir/borrow_check/nll/explain_borrow/find_use.rs
+++ b/src/librustc_mir/borrow_check/nll/explain_borrow/find_use.rs
@@ -5,12 +5,12 @@ use crate::borrow_check::nll::region_infer::{Cause, RegionInferenceContext};
 use crate::borrow_check::nll::ToRegionVid;
 use crate::util::liveness::{self, DefUse};
 use rustc::mir::visit::{MirVisitable, PlaceContext, Visitor};
-use rustc::mir::{Local, Location, Mir};
+use rustc::mir::{Local, Location, Body};
 use rustc::ty::{RegionVid, TyCtxt};
 use rustc_data_structures::fx::FxHashSet;
 
 crate fn find<'tcx>(
-    mir: &Mir<'tcx>,
+    mir: &Body<'tcx>,
     regioncx: &Rc<RegionInferenceContext<'tcx>>,
     tcx: TyCtxt<'_, '_, 'tcx>,
     region_vid: RegionVid,
@@ -28,7 +28,7 @@ crate fn find<'tcx>(
 }
 
 struct UseFinder<'cx, 'gcx: 'tcx, 'tcx: 'cx> {
-    mir: &'cx Mir<'tcx>,
+    mir: &'cx Body<'tcx>,
     regioncx: &'cx Rc<RegionInferenceContext<'tcx>>,
     tcx: TyCtxt<'cx, 'gcx, 'tcx>,
     region_vid: RegionVid,
@@ -100,7 +100,7 @@ impl<'cx, 'gcx, 'tcx> UseFinder<'cx, 'gcx, 'tcx> {
 }
 
 struct DefUseVisitor<'cx, 'gcx: 'tcx, 'tcx: 'cx> {
-    mir: &'cx Mir<'tcx>,
+    mir: &'cx Body<'tcx>,
     tcx: TyCtxt<'cx, 'gcx, 'tcx>,
     region_vid: RegionVid,
     def_use_result: Option<DefUseResult>,
diff --git a/src/librustc_mir/borrow_check/nll/explain_borrow/mod.rs b/src/librustc_mir/borrow_check/nll/explain_borrow/mod.rs
index 6bca470bf3e..60c46b36f5f 100644
--- a/src/librustc_mir/borrow_check/nll/explain_borrow/mod.rs
+++ b/src/librustc_mir/borrow_check/nll/explain_borrow/mod.rs
@@ -6,7 +6,7 @@ use crate::borrow_check::nll::region_infer::{Cause, RegionName};
 use crate::borrow_check::nll::ConstraintDescription;
 use crate::borrow_check::{MirBorrowckCtxt, WriteKind};
 use rustc::mir::{
-    CastKind, ConstraintCategory, FakeReadCause, Local, Location, Mir, Operand, Place, PlaceBase,
+    CastKind, ConstraintCategory, FakeReadCause, Local, Location, Body, Operand, Place, PlaceBase,
     Projection, ProjectionElem, Rvalue, Statement, StatementKind, TerminatorKind,
 };
 use rustc::ty::{self, TyCtxt};
@@ -54,7 +54,7 @@ impl BorrowExplanation {
     pub(in crate::borrow_check) fn add_explanation_to_diagnostic<'cx, 'gcx, 'tcx>(
         &self,
         tcx: TyCtxt<'cx, 'gcx, 'tcx>,
-        mir: &Mir<'tcx>,
+        mir: &Body<'tcx>,
         err: &mut DiagnosticBuilder<'_>,
         borrow_desc: &str,
         borrow_span: Option<Span>,
diff --git a/src/librustc_mir/borrow_check/nll/invalidation.rs b/src/librustc_mir/borrow_check/nll/invalidation.rs
index e3ab48ccff1..017f4d48c12 100644
--- a/src/librustc_mir/borrow_check/nll/invalidation.rs
+++ b/src/librustc_mir/borrow_check/nll/invalidation.rs
@@ -11,7 +11,7 @@ use crate::borrow_check::path_utils::*;
 use crate::dataflow::indexes::BorrowIndex;
 use rustc::ty::TyCtxt;
 use rustc::mir::visit::Visitor;
-use rustc::mir::{BasicBlock, Location, Mir, Place, PlaceBase, Rvalue};
+use rustc::mir::{BasicBlock, Location, Body, Place, PlaceBase, Rvalue};
 use rustc::mir::{Statement, StatementKind};
 use rustc::mir::TerminatorKind;
 use rustc::mir::{Operand, BorrowKind};
@@ -21,7 +21,7 @@ pub(super) fn generate_invalidates<'cx, 'gcx, 'tcx>(
     tcx: TyCtxt<'cx, 'gcx, 'tcx>,
     all_facts: &mut Option<AllFacts>,
     location_table: &LocationTable,
-    mir: &Mir<'tcx>,
+    mir: &Body<'tcx>,
     borrow_set: &BorrowSet<'tcx>,
 ) {
     if all_facts.is_none() {
@@ -39,7 +39,7 @@ pub(super) fn generate_invalidates<'cx, 'gcx, 'tcx>(
             mir,
             dominators,
         };
-        ig.visit_mir(mir);
+        ig.visit_body(mir);
     }
 }
 
@@ -47,7 +47,7 @@ struct InvalidationGenerator<'cx, 'tcx: 'cx, 'gcx: 'tcx> {
     tcx: TyCtxt<'cx, 'gcx, 'tcx>,
     all_facts: &'cx mut AllFacts,
     location_table: &'cx LocationTable,
-    mir: &'cx Mir<'tcx>,
+    mir: &'cx Body<'tcx>,
     dominators: Dominators<BasicBlock>,
     borrow_set: &'cx BorrowSet<'tcx>,
 }
diff --git a/src/librustc_mir/borrow_check/nll/mod.rs b/src/librustc_mir/borrow_check/nll/mod.rs
index fa490c108c8..0fb1705c8c2 100644
--- a/src/librustc_mir/borrow_check/nll/mod.rs
+++ b/src/librustc_mir/borrow_check/nll/mod.rs
@@ -11,7 +11,7 @@ use crate::transform::MirSource;
 use crate::borrow_check::Upvar;
 use rustc::hir::def_id::DefId;
 use rustc::infer::InferCtxt;
-use rustc::mir::{ClosureOutlivesSubject, ClosureRegionRequirements, Mir};
+use rustc::mir::{ClosureOutlivesSubject, ClosureRegionRequirements, Body};
 use rustc::ty::{self, RegionKind, RegionVid};
 use rustc_errors::Diagnostic;
 use std::fmt::Debug;
@@ -50,7 +50,7 @@ pub(in crate::borrow_check) fn replace_regions_in_mir<'cx, 'gcx, 'tcx>(
     infcx: &InferCtxt<'cx, 'gcx, 'tcx>,
     def_id: DefId,
     param_env: ty::ParamEnv<'tcx>,
-    mir: &mut Mir<'tcx>,
+    mir: &mut Body<'tcx>,
 ) -> UniversalRegions<'tcx> {
     debug!("replace_regions_in_mir(def_id={:?})", def_id);
 
@@ -73,7 +73,7 @@ pub(in crate::borrow_check) fn compute_regions<'cx, 'gcx, 'tcx>(
     infcx: &InferCtxt<'cx, 'gcx, 'tcx>,
     def_id: DefId,
     universal_regions: UniversalRegions<'tcx>,
-    mir: &Mir<'tcx>,
+    mir: &Body<'tcx>,
     upvars: &[Upvar],
     location_table: &LocationTable,
     param_env: ty::ParamEnv<'gcx>,
@@ -213,7 +213,7 @@ pub(in crate::borrow_check) fn compute_regions<'cx, 'gcx, 'tcx>(
 fn dump_mir_results<'a, 'gcx, 'tcx>(
     infcx: &InferCtxt<'a, 'gcx, 'tcx>,
     source: MirSource<'tcx>,
-    mir: &Mir<'tcx>,
+    mir: &Body<'tcx>,
     regioncx: &RegionInferenceContext<'_>,
     closure_region_requirements: &Option<ClosureRegionRequirements<'_>>,
 ) {
@@ -273,7 +273,7 @@ fn dump_mir_results<'a, 'gcx, 'tcx>(
 
 fn dump_annotation<'a, 'gcx, 'tcx>(
     infcx: &InferCtxt<'a, 'gcx, 'tcx>,
-    mir: &Mir<'tcx>,
+    mir: &Body<'tcx>,
     mir_def_id: DefId,
     regioncx: &RegionInferenceContext<'tcx>,
     closure_region_requirements: &Option<ClosureRegionRequirements<'_>>,
diff --git a/src/librustc_mir/borrow_check/nll/region_infer/error_reporting/mod.rs b/src/librustc_mir/borrow_check/nll/region_infer/error_reporting/mod.rs
index 18ca105070e..db43ea0558c 100644
--- a/src/librustc_mir/borrow_check/nll/region_infer/error_reporting/mod.rs
+++ b/src/librustc_mir/borrow_check/nll/region_infer/error_reporting/mod.rs
@@ -9,7 +9,7 @@ use rustc::hir::def_id::DefId;
 use rustc::infer::error_reporting::nice_region_error::NiceRegionError;
 use rustc::infer::InferCtxt;
 use rustc::infer::NLLRegionVariableOrigin;
-use rustc::mir::{ConstraintCategory, Location, Mir};
+use rustc::mir::{ConstraintCategory, Location, Body};
 use rustc::ty::{self, RegionVid};
 use rustc_data_structures::indexed_vec::IndexVec;
 use rustc_errors::{Diagnostic, DiagnosticBuilder};
@@ -62,7 +62,7 @@ impl<'tcx> RegionInferenceContext<'tcx> {
     /// path to blame.
     fn best_blame_constraint(
         &self,
-        mir: &Mir<'tcx>,
+        mir: &Body<'tcx>,
         from_region: RegionVid,
         target_test: impl Fn(RegionVid) -> bool,
     ) -> (ConstraintCategory, bool, Span) {
@@ -237,7 +237,7 @@ impl<'tcx> RegionInferenceContext<'tcx> {
     /// Here we would be invoked with `fr = 'a` and `outlived_fr = `'b`.
     pub(super) fn report_error(
         &self,
-        mir: &Mir<'tcx>,
+        mir: &Body<'tcx>,
         upvars: &[Upvar],
         infcx: &InferCtxt<'_, '_, 'tcx>,
         mir_def_id: DefId,
@@ -357,7 +357,7 @@ impl<'tcx> RegionInferenceContext<'tcx> {
     /// ```
     fn report_fnmut_error(
         &self,
-        mir: &Mir<'tcx>,
+        mir: &Body<'tcx>,
         upvars: &[Upvar],
         infcx: &InferCtxt<'_, '_, 'tcx>,
         mir_def_id: DefId,
@@ -422,7 +422,7 @@ impl<'tcx> RegionInferenceContext<'tcx> {
     /// ```
     fn report_escaping_data_error(
         &self,
-        mir: &Mir<'tcx>,
+        mir: &Body<'tcx>,
         upvars: &[Upvar],
         infcx: &InferCtxt<'_, '_, 'tcx>,
         mir_def_id: DefId,
@@ -514,7 +514,7 @@ impl<'tcx> RegionInferenceContext<'tcx> {
     /// ```
     fn report_general_error(
         &self,
-        mir: &Mir<'tcx>,
+        mir: &Body<'tcx>,
         upvars: &[Upvar],
         infcx: &InferCtxt<'_, '_, 'tcx>,
         mir_def_id: DefId,
@@ -667,7 +667,7 @@ impl<'tcx> RegionInferenceContext<'tcx> {
 
     crate fn free_region_constraint_info(
         &self,
-        mir: &Mir<'tcx>,
+        mir: &Body<'tcx>,
         upvars: &[Upvar],
         mir_def_id: DefId,
         infcx: &InferCtxt<'_, '_, 'tcx>,
@@ -724,7 +724,7 @@ impl<'tcx> RegionInferenceContext<'tcx> {
     // Finds a good span to blame for the fact that `fr1` outlives `fr2`.
     crate fn find_outlives_blame_span(
         &self,
-        mir: &Mir<'tcx>,
+        mir: &Body<'tcx>,
         fr1: RegionVid,
         fr2: RegionVid,
     ) -> (ConstraintCategory, Span) {
@@ -735,7 +735,7 @@ impl<'tcx> RegionInferenceContext<'tcx> {
 
     fn retrieve_closure_constraint_info(
         &self,
-        mir: &Mir<'tcx>,
+        mir: &Body<'tcx>,
         constraint: &OutlivesConstraint,
     ) -> (ConstraintCategory, bool, Span) {
         let loc = match constraint.locations {
diff --git a/src/librustc_mir/borrow_check/nll/region_infer/error_reporting/region_name.rs b/src/librustc_mir/borrow_check/nll/region_infer/error_reporting/region_name.rs
index f3cfc1a59a9..25415039fc8 100644
--- a/src/librustc_mir/borrow_check/nll/region_infer/error_reporting/region_name.rs
+++ b/src/librustc_mir/borrow_check/nll/region_infer/error_reporting/region_name.rs
@@ -7,7 +7,7 @@ use rustc::hir;
 use rustc::hir::def::{Res, DefKind};
 use rustc::hir::def_id::DefId;
 use rustc::infer::InferCtxt;
-use rustc::mir::Mir;
+use rustc::mir::Body;
 use rustc::ty::subst::{SubstsRef, UnpackedKind};
 use rustc::ty::{self, RegionKind, RegionVid, Ty, TyCtxt};
 use rustc::ty::print::RegionHighlightMode;
@@ -152,7 +152,7 @@ impl<'tcx> RegionInferenceContext<'tcx> {
     crate fn give_region_a_name(
         &self,
         infcx: &InferCtxt<'_, '_, 'tcx>,
-        mir: &Mir<'tcx>,
+        mir: &Body<'tcx>,
         upvars: &[Upvar],
         mir_def_id: DefId,
         fr: RegionVid,
@@ -332,7 +332,7 @@ impl<'tcx> RegionInferenceContext<'tcx> {
     fn give_name_if_anonymous_region_appears_in_arguments(
         &self,
         infcx: &InferCtxt<'_, '_, 'tcx>,
-        mir: &Mir<'tcx>,
+        mir: &Body<'tcx>,
         mir_def_id: DefId,
         fr: RegionVid,
         counter: &mut usize,
@@ -360,7 +360,7 @@ impl<'tcx> RegionInferenceContext<'tcx> {
     fn give_name_if_we_can_match_hir_ty_from_argument(
         &self,
         infcx: &InferCtxt<'_, '_, 'tcx>,
-        mir: &Mir<'tcx>,
+        mir: &Body<'tcx>,
         mir_def_id: DefId,
         needle_fr: RegionVid,
         argument_ty: Ty<'tcx>,
@@ -406,7 +406,7 @@ impl<'tcx> RegionInferenceContext<'tcx> {
     fn give_name_if_we_cannot_match_hir_ty(
         &self,
         infcx: &InferCtxt<'_, '_, 'tcx>,
-        mir: &Mir<'tcx>,
+        mir: &Body<'tcx>,
         needle_fr: RegionVid,
         argument_ty: Ty<'tcx>,
         counter: &mut usize,
@@ -676,7 +676,7 @@ impl<'tcx> RegionInferenceContext<'tcx> {
     fn give_name_if_anonymous_region_appears_in_output(
         &self,
         infcx: &InferCtxt<'_, '_, 'tcx>,
-        mir: &Mir<'tcx>,
+        mir: &Body<'tcx>,
         mir_def_id: DefId,
         fr: RegionVid,
         counter: &mut usize,
@@ -736,7 +736,7 @@ impl<'tcx> RegionInferenceContext<'tcx> {
     fn give_name_if_anonymous_region_appears_in_yield_ty(
         &self,
         infcx: &InferCtxt<'_, '_, 'tcx>,
-        mir: &Mir<'tcx>,
+        mir: &Body<'tcx>,
         mir_def_id: DefId,
         fr: RegionVid,
         counter: &mut usize,
diff --git a/src/librustc_mir/borrow_check/nll/region_infer/error_reporting/var_name.rs b/src/librustc_mir/borrow_check/nll/region_infer/error_reporting/var_name.rs
index d8f34233839..c02a492c341 100644
--- a/src/librustc_mir/borrow_check/nll/region_infer/error_reporting/var_name.rs
+++ b/src/librustc_mir/borrow_check/nll/region_infer/error_reporting/var_name.rs
@@ -1,7 +1,7 @@
 use crate::borrow_check::nll::region_infer::RegionInferenceContext;
 use crate::borrow_check::nll::ToRegionVid;
 use crate::borrow_check::Upvar;
-use rustc::mir::{Local, Mir};
+use rustc::mir::{Local, Body};
 use rustc::ty::{RegionVid, TyCtxt};
 use rustc_data_structures::indexed_vec::Idx;
 use syntax::source_map::Span;
@@ -11,7 +11,7 @@ impl<'tcx> RegionInferenceContext<'tcx> {
     crate fn get_var_name_and_span_for_region(
         &self,
         tcx: TyCtxt<'_, '_, 'tcx>,
-        mir: &Mir<'tcx>,
+        mir: &Body<'tcx>,
         upvars: &[Upvar],
         fr: RegionVid,
     ) -> Option<(Option<Symbol>, Span)> {
@@ -120,7 +120,7 @@ impl<'tcx> RegionInferenceContext<'tcx> {
     /// declared.
     crate fn get_argument_name_and_span_for_region(
         &self,
-        mir: &Mir<'tcx>,
+        mir: &Body<'tcx>,
         argument_index: usize,
     ) -> (Option<Symbol>, Span) {
         let implicit_inputs = self.universal_regions.defining_ty.implicit_inputs();
diff --git a/src/librustc_mir/borrow_check/nll/region_infer/mod.rs b/src/librustc_mir/borrow_check/nll/region_infer/mod.rs
index 9dd18ab76a5..4a00571feb1 100644
--- a/src/librustc_mir/borrow_check/nll/region_infer/mod.rs
+++ b/src/librustc_mir/borrow_check/nll/region_infer/mod.rs
@@ -13,7 +13,7 @@ use rustc::infer::region_constraints::{GenericKind, VarInfos, VerifyBound};
 use rustc::infer::{InferCtxt, NLLRegionVariableOrigin, RegionVariableOrigin};
 use rustc::mir::{
     ClosureOutlivesRequirement, ClosureOutlivesSubject, ClosureRegionRequirements,
-    ConstraintCategory, Local, Location, Mir,
+    ConstraintCategory, Local, Location, Body,
 };
 use rustc::ty::{self, subst::SubstsRef, RegionVid, Ty, TyCtxt, TypeFoldable};
 use rustc::util::common::{self, ErrorReported};
@@ -185,7 +185,7 @@ impl<'tcx> RegionInferenceContext<'tcx> {
         universal_regions: Rc<UniversalRegions<'tcx>>,
         placeholder_indices: Rc<PlaceholderIndices>,
         universal_region_relations: Rc<UniversalRegionRelations<'tcx>>,
-        _mir: &Mir<'tcx>,
+        _mir: &Body<'tcx>,
         outlives_constraints: ConstraintSet,
         closure_bounds_mapping: FxHashMap<
             Location,
@@ -400,7 +400,7 @@ impl<'tcx> RegionInferenceContext<'tcx> {
     pub(super) fn solve<'gcx>(
         &mut self,
         infcx: &InferCtxt<'_, 'gcx, 'tcx>,
-        mir: &Mir<'tcx>,
+        mir: &Body<'tcx>,
         upvars: &[Upvar],
         mir_def_id: DefId,
         errors_buffer: &mut Vec<Diagnostic>,
@@ -416,7 +416,7 @@ impl<'tcx> RegionInferenceContext<'tcx> {
     fn solve_inner<'gcx>(
         &mut self,
         infcx: &InferCtxt<'_, 'gcx, 'tcx>,
-        mir: &Mir<'tcx>,
+        mir: &Body<'tcx>,
         upvars: &[Upvar],
         mir_def_id: DefId,
         errors_buffer: &mut Vec<Diagnostic>,
@@ -468,7 +468,7 @@ impl<'tcx> RegionInferenceContext<'tcx> {
     /// for each region variable until all the constraints are
     /// satisfied. Note that some values may grow **too** large to be
     /// feasible, but we check this later.
-    fn propagate_constraints(&mut self, _mir: &Mir<'tcx>) {
+    fn propagate_constraints(&mut self, _mir: &Body<'tcx>) {
         debug!("propagate_constraints()");
 
         debug!("propagate_constraints: constraints={:#?}", {
@@ -581,7 +581,7 @@ impl<'tcx> RegionInferenceContext<'tcx> {
     fn check_type_tests<'gcx>(
         &self,
         infcx: &InferCtxt<'_, 'gcx, 'tcx>,
-        mir: &Mir<'tcx>,
+        mir: &Body<'tcx>,
         mir_def_id: DefId,
         mut propagated_outlives_requirements: Option<&mut Vec<ClosureOutlivesRequirement<'gcx>>>,
         errors_buffer: &mut Vec<Diagnostic>,
@@ -725,7 +725,7 @@ impl<'tcx> RegionInferenceContext<'tcx> {
     fn try_promote_type_test<'gcx>(
         &self,
         infcx: &InferCtxt<'_, 'gcx, 'tcx>,
-        mir: &Mir<'tcx>,
+        mir: &Body<'tcx>,
         type_test: &TypeTest<'tcx>,
         propagated_outlives_requirements: &mut Vec<ClosureOutlivesRequirement<'gcx>>,
     ) -> bool {
@@ -944,7 +944,7 @@ impl<'tcx> RegionInferenceContext<'tcx> {
     fn eval_verify_bound(
         &self,
         tcx: TyCtxt<'_, '_, 'tcx>,
-        mir: &Mir<'tcx>,
+        mir: &Body<'tcx>,
         generic_ty: Ty<'tcx>,
         lower_bound: RegionVid,
         verify_bound: &VerifyBound<'tcx>,
@@ -977,7 +977,7 @@ impl<'tcx> RegionInferenceContext<'tcx> {
     fn eval_if_eq(
         &self,
         tcx: TyCtxt<'_, '_, 'tcx>,
-        mir: &Mir<'tcx>,
+        mir: &Body<'tcx>,
         generic_ty: Ty<'tcx>,
         lower_bound: RegionVid,
         test_ty: Ty<'tcx>,
@@ -1037,7 +1037,7 @@ impl<'tcx> RegionInferenceContext<'tcx> {
     // Evaluate whether `sup_region: sub_region @ point`.
     fn eval_outlives(
         &self,
-        _mir: &Mir<'tcx>,
+        _mir: &Body<'tcx>,
         sup_region: RegionVid,
         sub_region: RegionVid,
     ) -> bool {
@@ -1105,7 +1105,7 @@ impl<'tcx> RegionInferenceContext<'tcx> {
     fn check_universal_regions<'gcx>(
         &self,
         infcx: &InferCtxt<'_, 'gcx, 'tcx>,
-        mir: &Mir<'tcx>,
+        mir: &Body<'tcx>,
         upvars: &[Upvar],
         mir_def_id: DefId,
         mut propagated_outlives_requirements: Option<&mut Vec<ClosureOutlivesRequirement<'gcx>>>,
@@ -1150,7 +1150,7 @@ impl<'tcx> RegionInferenceContext<'tcx> {
     fn check_universal_region<'gcx>(
         &self,
         infcx: &InferCtxt<'_, 'gcx, 'tcx>,
-        mir: &Mir<'tcx>,
+        mir: &Body<'tcx>,
         upvars: &[Upvar],
         mir_def_id: DefId,
         longer_fr: RegionVid,
@@ -1216,7 +1216,7 @@ impl<'tcx> RegionInferenceContext<'tcx> {
         longer_fr: RegionVid,
         shorter_fr: RegionVid,
         infcx: &InferCtxt<'_, 'gcx, 'tcx>,
-        mir: &Mir<'tcx>,
+        mir: &Body<'tcx>,
         upvars: &[Upvar],
         mir_def_id: DefId,
         propagated_outlives_requirements: &mut Option<&mut Vec<ClosureOutlivesRequirement<'gcx>>>,
@@ -1282,7 +1282,7 @@ impl<'tcx> RegionInferenceContext<'tcx> {
     fn check_bound_universal_region<'gcx>(
         &self,
         infcx: &InferCtxt<'_, 'gcx, 'tcx>,
-        mir: &Mir<'tcx>,
+        mir: &Body<'tcx>,
         _mir_def_id: DefId,
         longer_fr: RegionVid,
         placeholder: ty::PlaceholderRegion,
diff --git a/src/librustc_mir/borrow_check/nll/region_infer/values.rs b/src/librustc_mir/borrow_check/nll/region_infer/values.rs
index 2101447965a..8822d7bb373 100644
--- a/src/librustc_mir/borrow_check/nll/region_infer/values.rs
+++ b/src/librustc_mir/borrow_check/nll/region_infer/values.rs
@@ -1,4 +1,4 @@
-use rustc::mir::{BasicBlock, Location, Mir};
+use rustc::mir::{BasicBlock, Location, Body};
 use rustc::ty::{self, RegionVid};
 use rustc_data_structures::bit_set::{HybridBitSet, SparseBitMatrix};
 use rustc_data_structures::fx::FxHashMap;
@@ -20,7 +20,7 @@ crate struct RegionValueElements {
 }
 
 impl RegionValueElements {
-    crate fn new(mir: &Mir<'_>) -> Self {
+    crate fn new(mir: &Body<'_>) -> Self {
         let mut num_points = 0;
         let statements_before_block: IndexVec<BasicBlock, usize> = mir.basic_blocks()
             .iter()
@@ -92,7 +92,7 @@ impl RegionValueElements {
     /// Pushes all predecessors of `index` onto `stack`.
     crate fn push_predecessors(
         &self,
-        mir: &Mir<'_>,
+        mir: &Body<'_>,
         index: PointIndex,
         stack: &mut Vec<PointIndex>,
     ) {
diff --git a/src/librustc_mir/borrow_check/nll/renumber.rs b/src/librustc_mir/borrow_check/nll/renumber.rs
index 58e567c39a9..a3b142c2ffc 100644
--- a/src/librustc_mir/borrow_check/nll/renumber.rs
+++ b/src/librustc_mir/borrow_check/nll/renumber.rs
@@ -1,17 +1,17 @@
 use rustc::ty::subst::SubstsRef;
 use rustc::ty::{self, ClosureSubsts, GeneratorSubsts, Ty, TypeFoldable};
-use rustc::mir::{Location, Mir};
+use rustc::mir::{Location, Body};
 use rustc::mir::visit::{MutVisitor, TyContext};
 use rustc::infer::{InferCtxt, NLLRegionVariableOrigin};
 
 /// Replaces all free regions appearing in the MIR with fresh
 /// inference variables, returning the number of variables created.
-pub fn renumber_mir<'tcx>(infcx: &InferCtxt<'_, '_, 'tcx>, mir: &mut Mir<'tcx>) {
+pub fn renumber_mir<'tcx>(infcx: &InferCtxt<'_, '_, 'tcx>, mir: &mut Body<'tcx>) {
     debug!("renumber_mir()");
     debug!("renumber_mir: mir.arg_count={:?}", mir.arg_count);
 
     let mut visitor = NLLVisitor { infcx };
-    visitor.visit_mir(mir);
+    visitor.visit_body(mir);
 }
 
 /// Replaces all regions appearing in `value` with fresh inference
@@ -47,12 +47,12 @@ impl<'a, 'gcx, 'tcx> NLLVisitor<'a, 'gcx, 'tcx> {
 }
 
 impl<'a, 'gcx, 'tcx> MutVisitor<'tcx> for NLLVisitor<'a, 'gcx, 'tcx> {
-    fn visit_mir(&mut self, mir: &mut Mir<'tcx>) {
+    fn visit_body(&mut self, mir: &mut Body<'tcx>) {
         for promoted in mir.promoted.iter_mut() {
-            self.visit_mir(promoted);
+            self.visit_body(promoted);
         }
 
-        self.super_mir(mir);
+        self.super_body(mir);
     }
 
     fn visit_ty(&mut self, ty: &mut Ty<'tcx>, ty_context: TyContext) {
diff --git a/src/librustc_mir/borrow_check/nll/type_check/input_output.rs b/src/librustc_mir/borrow_check/nll/type_check/input_output.rs
index 50828c294fa..120088e1784 100644
--- a/src/librustc_mir/borrow_check/nll/type_check/input_output.rs
+++ b/src/librustc_mir/borrow_check/nll/type_check/input_output.rs
@@ -20,7 +20,7 @@ use super::{Locations, TypeChecker};
 impl<'a, 'gcx, 'tcx> TypeChecker<'a, 'gcx, 'tcx> {
     pub(super) fn equate_inputs_and_outputs(
         &mut self,
-        mir: &Mir<'tcx>,
+        mir: &Body<'tcx>,
         universal_regions: &UniversalRegions<'tcx>,
         normalized_inputs_and_output: &[Ty<'tcx>],
     ) {
diff --git a/src/librustc_mir/borrow_check/nll/type_check/liveness/local_use_map.rs b/src/librustc_mir/borrow_check/nll/type_check/liveness/local_use_map.rs
index 6ba41806a31..e1a7b9babd4 100644
--- a/src/librustc_mir/borrow_check/nll/type_check/liveness/local_use_map.rs
+++ b/src/librustc_mir/borrow_check/nll/type_check/liveness/local_use_map.rs
@@ -1,7 +1,7 @@
 use crate::borrow_check::nll::region_infer::values::{PointIndex, RegionValueElements};
 use crate::util::liveness::{categorize, DefUse};
 use rustc::mir::visit::{PlaceContext, Visitor};
-use rustc::mir::{Local, Location, Mir};
+use rustc::mir::{Local, Location, Body};
 use rustc_data_structures::indexed_vec::{Idx, IndexVec};
 use rustc_data_structures::vec_linked_list as vll;
 
@@ -60,7 +60,7 @@ impl LocalUseMap {
     crate fn build(
         live_locals: &Vec<Local>,
         elements: &RegionValueElements,
-        mir: &Mir<'_>,
+        mir: &Body<'_>,
     ) -> Self {
         let nones = IndexVec::from_elem_n(None, mir.local_decls.len());
         let mut local_use_map = LocalUseMap {
@@ -81,7 +81,7 @@ impl LocalUseMap {
             elements,
             locals_with_use_data,
         }
-        .visit_mir(mir);
+        .visit_body(mir);
 
         local_use_map
     }
diff --git a/src/librustc_mir/borrow_check/nll/type_check/liveness/mod.rs b/src/librustc_mir/borrow_check/nll/type_check/liveness/mod.rs
index 58a164b38f9..3cefab36e23 100644
--- a/src/librustc_mir/borrow_check/nll/type_check/liveness/mod.rs
+++ b/src/librustc_mir/borrow_check/nll/type_check/liveness/mod.rs
@@ -7,7 +7,7 @@ use crate::borrow_check::nll::ToRegionVid;
 use crate::dataflow::move_paths::MoveData;
 use crate::dataflow::FlowAtLocation;
 use crate::dataflow::MaybeInitializedPlaces;
-use rustc::mir::{Local, Mir};
+use rustc::mir::{Local, Body};
 use rustc::ty::{RegionVid, TyCtxt};
 use rustc_data_structures::fx::FxHashSet;
 use std::rc::Rc;
@@ -27,7 +27,7 @@ mod trace;
 /// performed before
 pub(super) fn generate<'gcx, 'tcx>(
     typeck: &mut TypeChecker<'_, 'gcx, 'tcx>,
-    mir: &Mir<'tcx>,
+    mir: &Body<'tcx>,
     elements: &Rc<RegionValueElements>,
     flow_inits: &mut FlowAtLocation<'tcx, MaybeInitializedPlaces<'_, 'gcx, 'tcx>>,
     move_data: &MoveData<'tcx>,
@@ -77,7 +77,7 @@ pub(super) fn generate<'gcx, 'tcx>(
 fn compute_live_locals(
     tcx: TyCtxt<'_, '_, 'tcx>,
     free_regions: &FxHashSet<RegionVid>,
-    mir: &Mir<'tcx>,
+    mir: &Body<'tcx>,
 ) -> Vec<Local> {
     let live_locals: Vec<Local> = mir
         .local_decls
diff --git a/src/librustc_mir/borrow_check/nll/type_check/liveness/trace.rs b/src/librustc_mir/borrow_check/nll/type_check/liveness/trace.rs
index 87e9a704fac..345780c4760 100644
--- a/src/librustc_mir/borrow_check/nll/type_check/liveness/trace.rs
+++ b/src/librustc_mir/borrow_check/nll/type_check/liveness/trace.rs
@@ -7,7 +7,7 @@ use crate::dataflow::indexes::MovePathIndex;
 use crate::dataflow::move_paths::MoveData;
 use crate::dataflow::{FlowAtLocation, FlowsAtLocation, MaybeInitializedPlaces};
 use rustc::infer::canonical::QueryRegionConstraint;
-use rustc::mir::{BasicBlock, ConstraintCategory, Local, Location, Mir};
+use rustc::mir::{BasicBlock, ConstraintCategory, Local, Location, Body};
 use rustc::traits::query::dropck_outlives::DropckOutlivesResult;
 use rustc::traits::query::type_op::outlives::DropckOutlives;
 use rustc::traits::query::type_op::TypeOp;
@@ -32,7 +32,7 @@ use std::rc::Rc;
 /// this respects `#[may_dangle]` annotations).
 pub(super) fn trace(
     typeck: &mut TypeChecker<'_, 'gcx, 'tcx>,
-    mir: &Mir<'tcx>,
+    mir: &Body<'tcx>,
     elements: &Rc<RegionValueElements>,
     flow_inits: &mut FlowAtLocation<'tcx, MaybeInitializedPlaces<'_, 'gcx, 'tcx>>,
     move_data: &MoveData<'tcx>,
@@ -72,7 +72,7 @@ where
     elements: &'me RegionValueElements,
 
     /// MIR we are analyzing.
-    mir: &'me Mir<'tcx>,
+    mir: &'me Body<'tcx>,
 
     /// Mapping to/from the various indices used for initialization tracking.
     move_data: &'me MoveData<'tcx>,
diff --git a/src/librustc_mir/borrow_check/nll/type_check/mod.rs b/src/librustc_mir/borrow_check/nll/type_check/mod.rs
index 20b7f7eef0a..ad3b2f985d7 100644
--- a/src/librustc_mir/borrow_check/nll/type_check/mod.rs
+++ b/src/librustc_mir/borrow_check/nll/type_check/mod.rs
@@ -112,7 +112,7 @@ mod relate_tys;
 pub(crate) fn type_check<'gcx, 'tcx>(
     infcx: &InferCtxt<'_, 'gcx, 'tcx>,
     param_env: ty::ParamEnv<'gcx>,
-    mir: &Mir<'tcx>,
+    mir: &Body<'tcx>,
     mir_def_id: DefId,
     universal_regions: &Rc<UniversalRegions<'tcx>>,
     location_table: &LocationTable,
@@ -179,7 +179,7 @@ fn type_check_internal<'a, 'gcx, 'tcx, R>(
     infcx: &'a InferCtxt<'a, 'gcx, 'tcx>,
     mir_def_id: DefId,
     param_env: ty::ParamEnv<'gcx>,
-    mir: &'a Mir<'tcx>,
+    mir: &'a Body<'tcx>,
     region_bound_pairs: &'a RegionBoundPairs<'tcx>,
     implicit_region_bound: ty::Region<'tcx>,
     borrowck_context: &'a mut BorrowCheckContext<'a, 'tcx>,
@@ -198,7 +198,7 @@ fn type_check_internal<'a, 'gcx, 'tcx, R>(
     );
     let errors_reported = {
         let mut verifier = TypeVerifier::new(&mut checker, mir);
-        verifier.visit_mir(mir);
+        verifier.visit_body(mir);
         verifier.errors_reported
     };
 
@@ -253,7 +253,7 @@ enum FieldAccessError {
 /// is a problem.
 struct TypeVerifier<'a, 'b: 'a, 'gcx: 'tcx, 'tcx: 'b> {
     cx: &'a mut TypeChecker<'b, 'gcx, 'tcx>,
-    mir: &'b Mir<'tcx>,
+    mir: &'b Body<'tcx>,
     last_span: Span,
     mir_def_id: DefId,
     errors_reported: bool,
@@ -368,7 +368,7 @@ impl<'a, 'b, 'gcx, 'tcx> Visitor<'tcx> for TypeVerifier<'a, 'b, 'gcx, 'tcx> {
         }
     }
 
-    fn visit_mir(&mut self, mir: &Mir<'tcx>) {
+    fn visit_body(&mut self, mir: &Body<'tcx>) {
         self.sanitize_type(&"return type", mir.return_ty());
         for local_decl in &mir.local_decls {
             self.sanitize_type(local_decl, local_decl.ty);
@@ -376,12 +376,12 @@ impl<'a, 'b, 'gcx, 'tcx> Visitor<'tcx> for TypeVerifier<'a, 'b, 'gcx, 'tcx> {
         if self.errors_reported {
             return;
         }
-        self.super_mir(mir);
+        self.super_body(mir);
     }
 }
 
 impl<'a, 'b, 'gcx, 'tcx> TypeVerifier<'a, 'b, 'gcx, 'tcx> {
-    fn new(cx: &'a mut TypeChecker<'b, 'gcx, 'tcx>, mir: &'b Mir<'tcx>) -> Self {
+    fn new(cx: &'a mut TypeChecker<'b, 'gcx, 'tcx>, mir: &'b Body<'tcx>) -> Self {
         TypeVerifier {
             mir,
             mir_def_id: cx.mir_def_id,
@@ -538,7 +538,7 @@ impl<'a, 'b, 'gcx, 'tcx> TypeVerifier<'a, 'b, 'gcx, 'tcx> {
         })
     }
 
-    fn sanitize_promoted(&mut self, promoted_mir: &'b Mir<'tcx>, location: Location) {
+    fn sanitize_promoted(&mut self, promoted_mir: &'b Body<'tcx>, location: Location) {
         // Determine the constraints from the promoted MIR by running the type
         // checker on the promoted MIR, then transfer the constraints back to
         // the main MIR, changing the locations to the provided location.
@@ -562,7 +562,7 @@ impl<'a, 'b, 'gcx, 'tcx> TypeVerifier<'a, 'b, 'gcx, 'tcx> {
             &mut closure_bounds
         );
 
-        self.visit_mir(promoted_mir);
+        self.visit_body(promoted_mir);
 
         if !self.errors_reported {
             // if verifier failed, don't do further checks to avoid ICEs
@@ -969,7 +969,7 @@ impl Locations {
     }
 
     /// Gets a span representing the location.
-    pub fn span(&self, mir: &Mir<'_>) -> Span {
+    pub fn span(&self, mir: &Body<'_>) -> Span {
         match self {
             Locations::All(span) => *span,
             Locations::Single(l) => mir.source_info(*l).span,
@@ -980,7 +980,7 @@ impl Locations {
 impl<'a, 'gcx, 'tcx> TypeChecker<'a, 'gcx, 'tcx> {
     fn new(
         infcx: &'a InferCtxt<'a, 'gcx, 'tcx>,
-        mir: &'a Mir<'tcx>,
+        mir: &'a Body<'tcx>,
         mir_def_id: DefId,
         param_env: ty::ParamEnv<'gcx>,
         region_bound_pairs: &'a RegionBoundPairs<'tcx>,
@@ -1317,7 +1317,7 @@ impl<'a, 'gcx, 'tcx> TypeChecker<'a, 'gcx, 'tcx> {
         self.infcx.tcx
     }
 
-    fn check_stmt(&mut self, mir: &Mir<'tcx>, stmt: &Statement<'tcx>, location: Location) {
+    fn check_stmt(&mut self, mir: &Body<'tcx>, stmt: &Statement<'tcx>, location: Location) {
         debug!("check_stmt: {:?}", stmt);
         let tcx = self.tcx();
         match stmt.kind {
@@ -1456,7 +1456,7 @@ impl<'a, 'gcx, 'tcx> TypeChecker<'a, 'gcx, 'tcx> {
 
     fn check_terminator(
         &mut self,
-        mir: &Mir<'tcx>,
+        mir: &Body<'tcx>,
         term: &Terminator<'tcx>,
         term_location: Location,
     ) {
@@ -1618,7 +1618,7 @@ impl<'a, 'gcx, 'tcx> TypeChecker<'a, 'gcx, 'tcx> {
 
     fn check_call_dest(
         &mut self,
-        mir: &Mir<'tcx>,
+        mir: &Body<'tcx>,
         term: &Terminator<'tcx>,
         sig: &ty::FnSig<'tcx>,
         destination: &Option<(Place<'tcx>, BasicBlock)>,
@@ -1687,7 +1687,7 @@ impl<'a, 'gcx, 'tcx> TypeChecker<'a, 'gcx, 'tcx> {
 
     fn check_call_inputs(
         &mut self,
-        mir: &Mir<'tcx>,
+        mir: &Body<'tcx>,
         term: &Terminator<'tcx>,
         sig: &ty::FnSig<'tcx>,
         args: &[Operand<'tcx>],
@@ -1728,7 +1728,7 @@ impl<'a, 'gcx, 'tcx> TypeChecker<'a, 'gcx, 'tcx> {
         }
     }
 
-    fn check_iscleanup(&mut self, mir: &Mir<'tcx>, block_data: &BasicBlockData<'tcx>) {
+    fn check_iscleanup(&mut self, mir: &Body<'tcx>, block_data: &BasicBlockData<'tcx>) {
         let is_cleanup = block_data.is_cleanup;
         self.last_span = block_data.terminator().source_info.span;
         match block_data.terminator().kind {
@@ -1820,7 +1820,7 @@ impl<'a, 'gcx, 'tcx> TypeChecker<'a, 'gcx, 'tcx> {
 
     fn assert_iscleanup(
         &mut self,
-        mir: &Mir<'tcx>,
+        mir: &Body<'tcx>,
         ctxt: &dyn fmt::Debug,
         bb: BasicBlock,
         iscleanuppad: bool,
@@ -1836,7 +1836,7 @@ impl<'a, 'gcx, 'tcx> TypeChecker<'a, 'gcx, 'tcx> {
         }
     }
 
-    fn check_local(&mut self, mir: &Mir<'tcx>, local: Local, local_decl: &LocalDecl<'tcx>) {
+    fn check_local(&mut self, mir: &Body<'tcx>, local: Local, local_decl: &LocalDecl<'tcx>) {
         match mir.local_kind(local) {
             LocalKind::ReturnPointer | LocalKind::Arg => {
                 // return values of normal functions are required to be
@@ -1938,7 +1938,7 @@ impl<'a, 'gcx, 'tcx> TypeChecker<'a, 'gcx, 'tcx> {
         }
     }
 
-    fn check_rvalue(&mut self, mir: &Mir<'tcx>, rvalue: &Rvalue<'tcx>, location: Location) {
+    fn check_rvalue(&mut self, mir: &Body<'tcx>, rvalue: &Rvalue<'tcx>, location: Location) {
         let tcx = self.tcx();
 
         match rvalue {
@@ -2274,7 +2274,7 @@ impl<'a, 'gcx, 'tcx> TypeChecker<'a, 'gcx, 'tcx> {
 
     fn check_aggregate_rvalue(
         &mut self,
-        mir: &Mir<'tcx>,
+        mir: &Body<'tcx>,
         rvalue: &Rvalue<'tcx>,
         aggregate_kind: &AggregateKind<'tcx>,
         operands: &[Operand<'tcx>],
@@ -2332,7 +2332,7 @@ impl<'a, 'gcx, 'tcx> TypeChecker<'a, 'gcx, 'tcx> {
     /// - `borrowed_place`: the place `P` being borrowed
     fn add_reborrow_constraint(
         &mut self,
-        mir: &Mir<'tcx>,
+        mir: &Body<'tcx>,
         location: Location,
         borrow_region: ty::Region<'tcx>,
         borrowed_place: &Place<'tcx>,
@@ -2621,7 +2621,7 @@ impl<'a, 'gcx, 'tcx> TypeChecker<'a, 'gcx, 'tcx> {
         })
     }
 
-    fn typeck_mir(&mut self, mir: &Mir<'tcx>) {
+    fn typeck_mir(&mut self, mir: &Body<'tcx>) {
         self.last_span = mir.span;
         debug!("run_on_mir: {:?}", mir.span);
 
diff --git a/src/librustc_mir/borrow_check/path_utils.rs b/src/librustc_mir/borrow_check/path_utils.rs
index caef8d8bc5a..557d235c23f 100644
--- a/src/librustc_mir/borrow_check/path_utils.rs
+++ b/src/librustc_mir/borrow_check/path_utils.rs
@@ -2,7 +2,7 @@ use crate::borrow_check::borrow_set::{BorrowSet, BorrowData, TwoPhaseActivation}
 use crate::borrow_check::places_conflict;
 use crate::borrow_check::AccessDepth;
 use crate::dataflow::indexes::BorrowIndex;
-use rustc::mir::{BasicBlock, Location, Mir, Place, PlaceBase};
+use rustc::mir::{BasicBlock, Location, Body, Place, PlaceBase};
 use rustc::mir::{ProjectionElem, BorrowKind};
 use rustc::ty::TyCtxt;
 use rustc_data_structures::graph::dominators::Dominators;
@@ -25,7 +25,7 @@ pub(super) enum Control {
 pub(super) fn each_borrow_involving_path<'a, 'tcx, 'gcx: 'tcx, F, I, S> (
     s: &mut S,
     tcx: TyCtxt<'a, 'gcx, 'tcx>,
-    mir: &Mir<'tcx>,
+    mir: &Body<'tcx>,
     _location: Location,
     access_place: (AccessDepth, &Place<'tcx>),
     borrow_set: &BorrowSet<'tcx>,
diff --git a/src/librustc_mir/borrow_check/place_ext.rs b/src/librustc_mir/borrow_check/place_ext.rs
index 9ad0e936e1b..9306e88e9ae 100644
--- a/src/librustc_mir/borrow_check/place_ext.rs
+++ b/src/librustc_mir/borrow_check/place_ext.rs
@@ -1,6 +1,6 @@
 use rustc::hir;
 use rustc::mir::ProjectionElem;
-use rustc::mir::{Mir, Place, PlaceBase, Mutability, Static, StaticKind};
+use rustc::mir::{Body, Place, PlaceBase, Mutability, Static, StaticKind};
 use rustc::ty::{self, TyCtxt};
 use crate::borrow_check::borrow_set::LocalsStateAtExit;
 
@@ -13,7 +13,7 @@ crate trait PlaceExt<'tcx> {
     fn ignore_borrow(
         &self,
         tcx: TyCtxt<'_, '_, 'tcx>,
-        mir: &Mir<'tcx>,
+        mir: &Body<'tcx>,
         locals_state_at_exit: &LocalsStateAtExit,
         ) -> bool;
 }
@@ -22,7 +22,7 @@ impl<'tcx> PlaceExt<'tcx> for Place<'tcx> {
     fn ignore_borrow(
         &self,
         tcx: TyCtxt<'_, '_, 'tcx>,
-        mir: &Mir<'tcx>,
+        mir: &Body<'tcx>,
         locals_state_at_exit: &LocalsStateAtExit,
     ) -> bool {
         self.iterate(|place_base, place_projection| {
diff --git a/src/librustc_mir/borrow_check/places_conflict.rs b/src/librustc_mir/borrow_check/places_conflict.rs
index c9e8d989478..74da3f96653 100644
--- a/src/librustc_mir/borrow_check/places_conflict.rs
+++ b/src/librustc_mir/borrow_check/places_conflict.rs
@@ -3,7 +3,7 @@ use crate::borrow_check::Overlap;
 use crate::borrow_check::{Deep, Shallow, AccessDepth};
 use rustc::hir;
 use rustc::mir::{
-    BorrowKind, Mir, Place, PlaceBase, Projection, ProjectionElem, ProjectionsIter,
+    BorrowKind, Body, Place, PlaceBase, Projection, ProjectionElem, ProjectionsIter,
     StaticKind
 };
 use rustc::ty::{self, TyCtxt};
@@ -26,7 +26,7 @@ crate enum PlaceConflictBias {
 /// dataflow).
 crate fn places_conflict<'gcx, 'tcx>(
     tcx: TyCtxt<'_, 'gcx, 'tcx>,
-    mir: &Mir<'tcx>,
+    mir: &Body<'tcx>,
     borrow_place: &Place<'tcx>,
     access_place: &Place<'tcx>,
     bias: PlaceConflictBias,
@@ -48,7 +48,7 @@ crate fn places_conflict<'gcx, 'tcx>(
 /// order to make the conservative choice and preserve soundness.
 pub(super) fn borrow_conflicts_with_place<'gcx, 'tcx>(
     tcx: TyCtxt<'_, 'gcx, 'tcx>,
-    mir: &Mir<'tcx>,
+    mir: &Body<'tcx>,
     borrow_place: &Place<'tcx>,
     borrow_kind: BorrowKind,
     access_place: &Place<'tcx>,
@@ -85,7 +85,7 @@ pub(super) fn borrow_conflicts_with_place<'gcx, 'tcx>(
 
 fn place_components_conflict<'gcx, 'tcx>(
     tcx: TyCtxt<'_, 'gcx, 'tcx>,
-    mir: &Mir<'tcx>,
+    mir: &Body<'tcx>,
     borrow_projections: (&PlaceBase<'tcx>, ProjectionsIter<'_, 'tcx>),
     borrow_kind: BorrowKind,
     access_projections: (&PlaceBase<'tcx>, ProjectionsIter<'_, 'tcx>),
@@ -367,7 +367,7 @@ fn place_base_conflict<'a, 'gcx: 'tcx, 'tcx>(
 // between `elem1` and `elem2`.
 fn place_projection_conflict<'a, 'gcx: 'tcx, 'tcx>(
     tcx: TyCtxt<'a, 'gcx, 'tcx>,
-    mir: &Mir<'tcx>,
+    mir: &Body<'tcx>,
     pi1: &Projection<'tcx>,
     pi2: &Projection<'tcx>,
     bias: PlaceConflictBias,
diff --git a/src/librustc_mir/borrow_check/prefixes.rs b/src/librustc_mir/borrow_check/prefixes.rs
index 866f1cf994e..0e1abeba70d 100644
--- a/src/librustc_mir/borrow_check/prefixes.rs
+++ b/src/librustc_mir/borrow_check/prefixes.rs
@@ -11,7 +11,7 @@ use super::MirBorrowckCtxt;
 
 use rustc::hir;
 use rustc::ty::{self, TyCtxt};
-use rustc::mir::{Mir, Place, PlaceBase, ProjectionElem};
+use rustc::mir::{Body, Place, PlaceBase, ProjectionElem};
 
 pub trait IsPrefixOf<'tcx> {
     fn is_prefix_of(&self, other: &Place<'tcx>) -> bool;
@@ -38,7 +38,7 @@ impl<'tcx> IsPrefixOf<'tcx> for Place<'tcx> {
 
 
 pub(super) struct Prefixes<'cx, 'gcx: 'tcx, 'tcx: 'cx> {
-    mir: &'cx Mir<'tcx>,
+    mir: &'cx Body<'tcx>,
     tcx: TyCtxt<'cx, 'gcx, 'tcx>,
     kind: PrefixSet,
     next: Option<&'cx Place<'tcx>>,
diff --git a/src/librustc_mir/borrow_check/used_muts.rs b/src/librustc_mir/borrow_check/used_muts.rs
index f4866fad9a5..abfc2f9466c 100644
--- a/src/librustc_mir/borrow_check/used_muts.rs
+++ b/src/librustc_mir/borrow_check/used_muts.rs
@@ -34,7 +34,7 @@ impl<'cx, 'gcx, 'tcx> MirBorrowckCtxt<'cx, 'gcx, 'tcx> {
                 never_initialized_mut_locals: &mut never_initialized_mut_locals,
                 mbcx: self,
             };
-            visitor.visit_mir(visitor.mbcx.mir);
+            visitor.visit_body(visitor.mbcx.mir);
         }
 
         // Take the union of the existed `used_mut` set with those variables we've found were
diff --git a/src/librustc_mir/build/mod.rs b/src/librustc_mir/build/mod.rs
index 55b5d5d1471..5797f9c3478 100644
--- a/src/librustc_mir/build/mod.rs
+++ b/src/librustc_mir/build/mod.rs
@@ -26,7 +26,7 @@ use syntax_pos::Span;
 use super::lints;
 
 /// Construct the MIR for a given `DefId`.
-pub fn mir_build<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>, def_id: DefId) -> Mir<'tcx> {
+pub fn mir_build<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>, def_id: DefId) -> Body<'tcx> {
     let id = tcx.hir().as_local_hir_id(def_id).unwrap();
 
     // Figure out what primary body this item has.
@@ -164,14 +164,14 @@ pub fn mir_build<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>, def_id: DefId) -> Mir<'t
             build::construct_const(cx, body_id, return_ty, return_ty_span)
         };
 
-        // Convert the Mir to global types.
+        // Convert the `mir::Body` to global types.
         let mut globalizer = GlobalizeMir {
             tcx,
             span: mir.span
         };
-        globalizer.visit_mir(&mut mir);
+        globalizer.visit_body(&mut mir);
         let mir = unsafe {
-            mem::transmute::<Mir<'_>, Mir<'tcx>>(mir)
+            mem::transmute::<Body<'_>, Body<'tcx>>(mir)
         };
 
         mir_util::dump_mir(tcx, None, "mir_map", &0,
@@ -236,22 +236,22 @@ impl<'a, 'gcx: 'tcx, 'tcx> MutVisitor<'tcx> for GlobalizeMir<'a, 'gcx> {
 fn create_constructor_shim<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
                                      ctor_id: hir::HirId,
                                      v: &'tcx hir::VariantData)
-                                     -> Mir<'tcx>
+                                     -> Body<'tcx>
 {
     let span = tcx.hir().span_by_hir_id(ctor_id);
     if let hir::VariantData::Tuple(ref fields, ctor_id) = *v {
         tcx.infer_ctxt().enter(|infcx| {
             let mut mir = shim::build_adt_ctor(&infcx, ctor_id, fields, span);
 
-            // Convert the Mir to global types.
+            // Convert the `mir::Body` to global types.
             let tcx = infcx.tcx.global_tcx();
             let mut globalizer = GlobalizeMir {
                 tcx,
                 span: mir.span
             };
-            globalizer.visit_mir(&mut mir);
+            globalizer.visit_body(&mut mir);
             let mir = unsafe {
-                mem::transmute::<Mir<'_>, Mir<'tcx>>(mir)
+                mem::transmute::<Body<'_>, Body<'tcx>>(mir)
             };
 
             mir_util::dump_mir(tcx, None, "mir_map", &0,
@@ -628,7 +628,7 @@ fn construct_fn<'a, 'gcx, 'tcx, A>(hir: Cx<'a, 'gcx, 'tcx>,
                                    yield_ty: Option<Ty<'gcx>>,
                                    return_ty_span: Span,
                                    body: &'gcx hir::Body)
-                                   -> Mir<'tcx>
+                                   -> Body<'tcx>
     where A: Iterator<Item=ArgInfo<'gcx>>
 {
     let arguments: Vec<_> = arguments.collect();
@@ -748,7 +748,7 @@ fn construct_const<'a, 'gcx, 'tcx>(
     body_id: hir::BodyId,
     const_ty: Ty<'tcx>,
     const_ty_span: Span,
-) -> Mir<'tcx> {
+) -> Body<'tcx> {
     let tcx = hir.tcx();
     let owner_id = tcx.hir().body_owner(body_id);
     let span = tcx.hir().span(owner_id);
@@ -787,7 +787,7 @@ fn construct_const<'a, 'gcx, 'tcx>(
 
 fn construct_error<'a, 'gcx, 'tcx>(hir: Cx<'a, 'gcx, 'tcx>,
                                    body_id: hir::BodyId)
-                                   -> Mir<'tcx> {
+                                   -> Body<'tcx> {
     let owner_id = hir.tcx().hir().body_owner(body_id);
     let span = hir.tcx().hir().span(owner_id);
     let ty = hir.tcx().types.err;
@@ -849,14 +849,14 @@ impl<'a, 'gcx, 'tcx> Builder<'a, 'gcx, 'tcx> {
 
     fn finish(self,
               yield_ty: Option<Ty<'tcx>>)
-              -> Mir<'tcx> {
+              -> Body<'tcx> {
         for (index, block) in self.cfg.basic_blocks.iter().enumerate() {
             if block.terminator.is_none() {
                 span_bug!(self.fn_span, "no terminator on block {:?}", index);
             }
         }
 
-        Mir::new(
+        Body::new(
             self.cfg.basic_blocks,
             self.source_scopes,
             ClearCrossCrate::Set(self.source_scope_local_data),
diff --git a/src/librustc_mir/const_eval.rs b/src/librustc_mir/const_eval.rs
index 7b3d0bceb68..0637c7b0588 100644
--- a/src/librustc_mir/const_eval.rs
+++ b/src/librustc_mir/const_eval.rs
@@ -55,7 +55,7 @@ pub(crate) fn mk_eval_cx<'a, 'mir, 'tcx>(
 pub(crate) fn eval_promoted<'a, 'mir, 'tcx>(
     tcx: TyCtxt<'a, 'tcx, 'tcx>,
     cid: GlobalId<'tcx>,
-    mir: &'mir mir::Mir<'tcx>,
+    mir: &'mir mir::Body<'tcx>,
     param_env: ty::ParamEnv<'tcx>,
 ) -> EvalResult<'tcx, MPlaceTy<'tcx>> {
     let span = tcx.def_span(cid.instance.def_id());
@@ -137,7 +137,7 @@ fn op_to_const<'tcx>(
 fn eval_body_using_ecx<'mir, 'tcx>(
     ecx: &mut CompileTimeEvalContext<'_, 'mir, 'tcx>,
     cid: GlobalId<'tcx>,
-    mir: &'mir mir::Mir<'tcx>,
+    mir: &'mir mir::Body<'tcx>,
     param_env: ty::ParamEnv<'tcx>,
 ) -> EvalResult<'tcx, MPlaceTy<'tcx>> {
     debug!("eval_body_using_ecx: {:?}, {:?}", cid, param_env);
@@ -331,7 +331,7 @@ impl<'a, 'mir, 'tcx> interpret::Machine<'a, 'mir, 'tcx>
         args: &[OpTy<'tcx>],
         dest: Option<PlaceTy<'tcx>>,
         ret: Option<mir::BasicBlock>,
-    ) -> EvalResult<'tcx, Option<&'mir mir::Mir<'tcx>>> {
+    ) -> EvalResult<'tcx, Option<&'mir mir::Body<'tcx>>> {
         debug!("eval_fn_call: {:?}", instance);
         // Only check non-glue functions
         if let ty::InstanceDef::Item(def_id) = instance.def {
diff --git a/src/librustc_mir/dataflow/drop_flag_effects.rs b/src/librustc_mir/dataflow/drop_flag_effects.rs
index 66ca4b4dc89..f9d88ab8795 100644
--- a/src/librustc_mir/dataflow/drop_flag_effects.rs
+++ b/src/librustc_mir/dataflow/drop_flag_effects.rs
@@ -1,4 +1,4 @@
-use rustc::mir::{self, Mir, Location};
+use rustc::mir::{self, Body, Location};
 use rustc::ty::{self, TyCtxt};
 use crate::util::elaborate_drops::DropFlagState;
 
@@ -47,7 +47,7 @@ pub fn move_path_children_matching<'tcx, F>(move_data: &MoveData<'tcx>,
 //
 // FIXME: we have to do something for moving slice patterns.
 fn place_contents_drop_state_cannot_differ<'a, 'gcx, 'tcx>(tcx: TyCtxt<'a, 'gcx, 'tcx>,
-                                                            mir: &Mir<'tcx>,
+                                                            mir: &Body<'tcx>,
                                                             place: &mir::Place<'tcx>) -> bool {
     let ty = place.ty(mir, tcx).ty;
     match ty.sty {
@@ -74,7 +74,7 @@ fn place_contents_drop_state_cannot_differ<'a, 'gcx, 'tcx>(tcx: TyCtxt<'a, 'gcx,
 
 pub(crate) fn on_lookup_result_bits<'a, 'gcx, 'tcx, F>(
     tcx: TyCtxt<'a, 'gcx, 'tcx>,
-    mir: &Mir<'tcx>,
+    mir: &Body<'tcx>,
     move_data: &MoveData<'tcx>,
     lookup_result: LookupResult,
     each_child: F)
@@ -92,7 +92,7 @@ pub(crate) fn on_lookup_result_bits<'a, 'gcx, 'tcx, F>(
 
 pub(crate) fn on_all_children_bits<'a, 'gcx, 'tcx, F>(
     tcx: TyCtxt<'a, 'gcx, 'tcx>,
-    mir: &Mir<'tcx>,
+    mir: &Body<'tcx>,
     move_data: &MoveData<'tcx>,
     move_path_index: MovePathIndex,
     mut each_child: F)
@@ -100,7 +100,7 @@ pub(crate) fn on_all_children_bits<'a, 'gcx, 'tcx, F>(
 {
     fn is_terminal_path<'a, 'gcx, 'tcx>(
         tcx: TyCtxt<'a, 'gcx, 'tcx>,
-        mir: &Mir<'tcx>,
+        mir: &Body<'tcx>,
         move_data: &MoveData<'tcx>,
         path: MovePathIndex) -> bool
     {
@@ -110,7 +110,7 @@ pub(crate) fn on_all_children_bits<'a, 'gcx, 'tcx, F>(
 
     fn on_all_children_bits<'a, 'gcx, 'tcx, F>(
         tcx: TyCtxt<'a, 'gcx, 'tcx>,
-        mir: &Mir<'tcx>,
+        mir: &Body<'tcx>,
         move_data: &MoveData<'tcx>,
         move_path_index: MovePathIndex,
         each_child: &mut F)
@@ -133,7 +133,7 @@ pub(crate) fn on_all_children_bits<'a, 'gcx, 'tcx, F>(
 
 pub(crate) fn on_all_drop_children_bits<'a, 'gcx, 'tcx, F>(
     tcx: TyCtxt<'a, 'gcx, 'tcx>,
-    mir: &Mir<'tcx>,
+    mir: &Body<'tcx>,
     ctxt: &MoveDataParamEnv<'gcx, 'tcx>,
     path: MovePathIndex,
     mut each_child: F)
@@ -156,7 +156,7 @@ pub(crate) fn on_all_drop_children_bits<'a, 'gcx, 'tcx, F>(
 
 pub(crate) fn drop_flag_effects_for_function_entry<'a, 'gcx, 'tcx, F>(
     tcx: TyCtxt<'a, 'gcx, 'tcx>,
-    mir: &Mir<'tcx>,
+    mir: &Body<'tcx>,
     ctxt: &MoveDataParamEnv<'gcx, 'tcx>,
     mut callback: F)
     where F: FnMut(MovePathIndex, DropFlagState)
@@ -173,7 +173,7 @@ pub(crate) fn drop_flag_effects_for_function_entry<'a, 'gcx, 'tcx, F>(
 
 pub(crate) fn drop_flag_effects_for_location<'a, 'gcx, 'tcx, F>(
     tcx: TyCtxt<'a, 'gcx, 'tcx>,
-    mir: &Mir<'tcx>,
+    mir: &Body<'tcx>,
     ctxt: &MoveDataParamEnv<'gcx, 'tcx>,
     loc: Location,
     mut callback: F)
@@ -205,7 +205,7 @@ pub(crate) fn drop_flag_effects_for_location<'a, 'gcx, 'tcx, F>(
 
 pub(crate) fn for_location_inits<'a, 'gcx, 'tcx, F>(
     tcx: TyCtxt<'a, 'gcx, 'tcx>,
-    mir: &Mir<'tcx>,
+    mir: &Body<'tcx>,
     move_data: &MoveData<'tcx>,
     loc: Location,
     mut callback: F)
diff --git a/src/librustc_mir/dataflow/graphviz.rs b/src/librustc_mir/dataflow/graphviz.rs
index d68377681f1..4965f1a585d 100644
--- a/src/librustc_mir/dataflow/graphviz.rs
+++ b/src/librustc_mir/dataflow/graphviz.rs
@@ -1,7 +1,7 @@
 //! Hook into libgraphviz for rendering dataflow graphs for MIR.
 
 use rustc::hir::def_id::DefId;
-use rustc::mir::{BasicBlock, Mir};
+use rustc::mir::{BasicBlock, Body};
 
 use std::fs;
 use std::io;
@@ -17,7 +17,7 @@ use super::DebugFormatted;
 pub trait MirWithFlowState<'tcx> {
     type BD: BitDenotation<'tcx>;
     fn def_id(&self) -> DefId;
-    fn mir(&self) -> &Mir<'tcx>;
+    fn mir(&self) -> &Body<'tcx>;
     fn flow_state(&self) -> &DataflowState<'tcx, Self::BD>;
 }
 
@@ -26,7 +26,7 @@ impl<'a, 'tcx, BD> MirWithFlowState<'tcx> for DataflowBuilder<'a, 'tcx, BD>
 {
     type BD = BD;
     fn def_id(&self) -> DefId { self.def_id }
-    fn mir(&self) -> &Mir<'tcx> { self.flow_state.mir() }
+    fn mir(&self) -> &Body<'tcx> { self.flow_state.mir() }
     fn flow_state(&self) -> &DataflowState<'tcx, Self::BD> { &self.flow_state.flow_state }
 }
 
@@ -59,7 +59,7 @@ pub type Node = BasicBlock;
 #[derive(Copy, Clone, PartialEq, Eq, Debug)]
 pub struct Edge { source: BasicBlock, index: usize }
 
-fn outgoing(mir: &Mir<'_>, bb: BasicBlock) -> Vec<Edge> {
+fn outgoing(mir: &Body<'_>, bb: BasicBlock) -> Vec<Edge> {
     (0..mir[bb].terminator().successors().count())
         .map(|index| Edge { source: bb, index: index}).collect()
 }
@@ -124,7 +124,7 @@ where MWF: MirWithFlowState<'tcx>,
                                          n: &Node,
                                          w: &mut W,
                                          block: BasicBlock,
-                                         mir: &Mir<'_>) -> io::Result<()> {
+                                         mir: &Body<'_>) -> io::Result<()> {
         // Header rows
         const HDRS: [&str; 4] = ["ENTRY", "MIR", "BLOCK GENS", "BLOCK KILLS"];
         const HDR_FMT: &str = "bgcolor=\"grey\"";
@@ -149,7 +149,7 @@ where MWF: MirWithFlowState<'tcx>,
                                             n: &Node,
                                             w: &mut W,
                                             block: BasicBlock,
-                                            mir: &Mir<'_>)
+                                            mir: &Body<'_>)
                                             -> io::Result<()> {
         let i = n.index();
 
@@ -199,7 +199,7 @@ where MWF: MirWithFlowState<'tcx>,
                                           n: &Node,
                                           w: &mut W,
                                           block: BasicBlock,
-                                          mir: &Mir<'_>)
+                                          mir: &Body<'_>)
                                           -> io::Result<()> {
         let i = n.index();
 
diff --git a/src/librustc_mir/dataflow/impls/borrowed_locals.rs b/src/librustc_mir/dataflow/impls/borrowed_locals.rs
index 65cbc83fbcb..47af10a1c50 100644
--- a/src/librustc_mir/dataflow/impls/borrowed_locals.rs
+++ b/src/librustc_mir/dataflow/impls/borrowed_locals.rs
@@ -12,16 +12,16 @@ use crate::dataflow::BitDenotation;
 /// immovable generators.
 #[derive(Copy, Clone)]
 pub struct HaveBeenBorrowedLocals<'a, 'tcx: 'a> {
-    mir: &'a Mir<'tcx>,
+    mir: &'a Body<'tcx>,
 }
 
 impl<'a, 'tcx: 'a> HaveBeenBorrowedLocals<'a, 'tcx> {
-    pub fn new(mir: &'a Mir<'tcx>)
+    pub fn new(mir: &'a Body<'tcx>)
                -> Self {
         HaveBeenBorrowedLocals { mir }
     }
 
-    pub fn mir(&self) -> &Mir<'tcx> {
+    pub fn mir(&self) -> &Body<'tcx> {
         self.mir
     }
 }
diff --git a/src/librustc_mir/dataflow/impls/borrows.rs b/src/librustc_mir/dataflow/impls/borrows.rs
index 43cb0ed4565..99051fb37f1 100644
--- a/src/librustc_mir/dataflow/impls/borrows.rs
+++ b/src/librustc_mir/dataflow/impls/borrows.rs
@@ -1,7 +1,7 @@
 use crate::borrow_check::borrow_set::{BorrowSet, BorrowData};
 use crate::borrow_check::place_ext::PlaceExt;
 
-use rustc::mir::{self, Location, Place, PlaceBase, Mir};
+use rustc::mir::{self, Location, Place, PlaceBase, Body};
 use rustc::ty::TyCtxt;
 use rustc::ty::RegionVid;
 
@@ -31,7 +31,7 @@ newtype_index! {
 /// borrows in compact bitvectors.
 pub struct Borrows<'a, 'gcx: 'tcx, 'tcx: 'a> {
     tcx: TyCtxt<'a, 'gcx, 'tcx>,
-    mir: &'a Mir<'tcx>,
+    mir: &'a Body<'tcx>,
 
     borrow_set: Rc<BorrowSet<'tcx>>,
     borrows_out_of_scope_at_location: FxHashMap<Location, Vec<BorrowIndex>>,
@@ -48,7 +48,7 @@ struct StackEntry {
 }
 
 fn precompute_borrows_out_of_scope<'tcx>(
-    mir: &Mir<'tcx>,
+    mir: &Body<'tcx>,
     regioncx: &Rc<RegionInferenceContext<'tcx>>,
     borrows_out_of_scope_at_location: &mut FxHashMap<Location, Vec<BorrowIndex>>,
     borrow_index: BorrowIndex,
@@ -136,7 +136,7 @@ fn precompute_borrows_out_of_scope<'tcx>(
 impl<'a, 'gcx, 'tcx> Borrows<'a, 'gcx, 'tcx> {
     crate fn new(
         tcx: TyCtxt<'a, 'gcx, 'tcx>,
-        mir: &'a Mir<'tcx>,
+        mir: &'a Body<'tcx>,
         nonlexical_regioncx: Rc<RegionInferenceContext<'tcx>>,
         borrow_set: &Rc<BorrowSet<'tcx>>,
     ) -> Self {
diff --git a/src/librustc_mir/dataflow/impls/mod.rs b/src/librustc_mir/dataflow/impls/mod.rs
index 03d55b84f32..4f3b180edd1 100644
--- a/src/librustc_mir/dataflow/impls/mod.rs
+++ b/src/librustc_mir/dataflow/impls/mod.rs
@@ -3,7 +3,7 @@
 //! zero-sized structure.
 
 use rustc::ty::TyCtxt;
-use rustc::mir::{self, Mir, Location};
+use rustc::mir::{self, Body, Location};
 use rustc_data_structures::bit_set::{BitSet, BitSetOperator};
 use rustc_data_structures::indexed_vec::Idx;
 
@@ -65,13 +65,13 @@ pub(super) mod borrows;
 /// places that would require a dynamic drop-flag at that statement.
 pub struct MaybeInitializedPlaces<'a, 'gcx: 'tcx, 'tcx: 'a> {
     tcx: TyCtxt<'a, 'gcx, 'tcx>,
-    mir: &'a Mir<'tcx>,
+    mir: &'a Body<'tcx>,
     mdpe: &'a MoveDataParamEnv<'gcx, 'tcx>,
 }
 
 impl<'a, 'gcx: 'tcx, 'tcx> MaybeInitializedPlaces<'a, 'gcx, 'tcx> {
     pub fn new(tcx: TyCtxt<'a, 'gcx, 'tcx>,
-               mir: &'a Mir<'tcx>,
+               mir: &'a Body<'tcx>,
                mdpe: &'a MoveDataParamEnv<'gcx, 'tcx>)
                -> Self
     {
@@ -120,13 +120,13 @@ impl<'a, 'gcx, 'tcx> HasMoveData<'tcx> for MaybeInitializedPlaces<'a, 'gcx, 'tcx
 /// places that would require a dynamic drop-flag at that statement.
 pub struct MaybeUninitializedPlaces<'a, 'gcx: 'tcx, 'tcx: 'a> {
     tcx: TyCtxt<'a, 'gcx, 'tcx>,
-    mir: &'a Mir<'tcx>,
+    mir: &'a Body<'tcx>,
     mdpe: &'a MoveDataParamEnv<'gcx, 'tcx>,
 }
 
 impl<'a, 'gcx, 'tcx> MaybeUninitializedPlaces<'a, 'gcx, 'tcx> {
     pub fn new(tcx: TyCtxt<'a, 'gcx, 'tcx>,
-               mir: &'a Mir<'tcx>,
+               mir: &'a Body<'tcx>,
                mdpe: &'a MoveDataParamEnv<'gcx, 'tcx>)
                -> Self
     {
@@ -174,13 +174,13 @@ impl<'a, 'gcx, 'tcx> HasMoveData<'tcx> for MaybeUninitializedPlaces<'a, 'gcx, 't
 /// that would require a dynamic drop-flag at that statement.
 pub struct DefinitelyInitializedPlaces<'a, 'gcx: 'tcx, 'tcx: 'a> {
     tcx: TyCtxt<'a, 'gcx, 'tcx>,
-    mir: &'a Mir<'tcx>,
+    mir: &'a Body<'tcx>,
     mdpe: &'a MoveDataParamEnv<'gcx, 'tcx>,
 }
 
 impl<'a, 'gcx, 'tcx: 'a> DefinitelyInitializedPlaces<'a, 'gcx, 'tcx> {
     pub fn new(tcx: TyCtxt<'a, 'gcx, 'tcx>,
-               mir: &'a Mir<'tcx>,
+               mir: &'a Body<'tcx>,
                mdpe: &'a MoveDataParamEnv<'gcx, 'tcx>)
                -> Self
     {
@@ -223,13 +223,13 @@ impl<'a, 'gcx, 'tcx: 'a> HasMoveData<'tcx> for DefinitelyInitializedPlaces<'a, '
 /// ```
 pub struct EverInitializedPlaces<'a, 'gcx: 'tcx, 'tcx: 'a> {
     tcx: TyCtxt<'a, 'gcx, 'tcx>,
-    mir: &'a Mir<'tcx>,
+    mir: &'a Body<'tcx>,
     mdpe: &'a MoveDataParamEnv<'gcx, 'tcx>,
 }
 
 impl<'a, 'gcx: 'tcx, 'tcx: 'a> EverInitializedPlaces<'a, 'gcx, 'tcx> {
     pub fn new(tcx: TyCtxt<'a, 'gcx, 'tcx>,
-               mir: &'a Mir<'tcx>,
+               mir: &'a Body<'tcx>,
                mdpe: &'a MoveDataParamEnv<'gcx, 'tcx>)
                -> Self
     {
diff --git a/src/librustc_mir/dataflow/impls/storage_liveness.rs b/src/librustc_mir/dataflow/impls/storage_liveness.rs
index 3bf11c57379..ab79d6cc947 100644
--- a/src/librustc_mir/dataflow/impls/storage_liveness.rs
+++ b/src/librustc_mir/dataflow/impls/storage_liveness.rs
@@ -5,16 +5,16 @@ use crate::dataflow::BitDenotation;
 
 #[derive(Copy, Clone)]
 pub struct MaybeStorageLive<'a, 'tcx: 'a> {
-    mir: &'a Mir<'tcx>,
+    mir: &'a Body<'tcx>,
 }
 
 impl<'a, 'tcx: 'a> MaybeStorageLive<'a, 'tcx> {
-    pub fn new(mir: &'a Mir<'tcx>)
+    pub fn new(mir: &'a Body<'tcx>)
                -> Self {
         MaybeStorageLive { mir }
     }
 
-    pub fn mir(&self) -> &Mir<'tcx> {
+    pub fn mir(&self) -> &Body<'tcx> {
         self.mir
     }
 }
diff --git a/src/librustc_mir/dataflow/mod.rs b/src/librustc_mir/dataflow/mod.rs
index a9d23a0afea..26bad0cb04d 100644
--- a/src/librustc_mir/dataflow/mod.rs
+++ b/src/librustc_mir/dataflow/mod.rs
@@ -7,7 +7,7 @@ use rustc_data_structures::work_queue::WorkQueue;
 
 use rustc::hir::def_id::DefId;
 use rustc::ty::{self, TyCtxt};
-use rustc::mir::{self, Mir, BasicBlock, BasicBlockData, Location, Statement, Terminator};
+use rustc::mir::{self, Body, BasicBlock, BasicBlockData, Location, Statement, Terminator};
 use rustc::mir::traversal;
 use rustc::session::Session;
 
@@ -122,7 +122,7 @@ pub struct MoveDataParamEnv<'gcx, 'tcx> {
 }
 
 pub(crate) fn do_dataflow<'a, 'gcx, 'tcx, BD, P>(tcx: TyCtxt<'a, 'gcx, 'tcx>,
-                                                 mir: &'a Mir<'tcx>,
+                                                 mir: &'a Body<'tcx>,
                                                  def_id: DefId,
                                                  attributes: &[ast::Attribute],
                                                  dead_unwinds: &BitSet<BasicBlock>,
@@ -343,13 +343,13 @@ pub(crate) trait DataflowResultsConsumer<'a, 'tcx: 'a> {
 
     // Delegated Hooks: Provide access to the MIR and process the flow state.
 
-    fn mir(&self) -> &'a Mir<'tcx>;
+    fn mir(&self) -> &'a Body<'tcx>;
 }
 
 pub fn state_for_location<'tcx, T: BitDenotation<'tcx>>(loc: Location,
                                                         analysis: &T,
                                                         result: &DataflowResults<'tcx, T>,
-                                                        mir: &Mir<'tcx>)
+                                                        mir: &Body<'tcx>)
     -> BitSet<T::Idx> {
     let mut on_entry = result.sets().on_entry_set_for(loc.block.index()).to_owned();
     let mut kill_set = on_entry.to_hybrid();
@@ -384,7 +384,7 @@ pub struct DataflowAnalysis<'a, 'tcx: 'a, O> where O: BitDenotation<'tcx>
 {
     flow_state: DataflowState<'tcx, O>,
     dead_unwinds: &'a BitSet<mir::BasicBlock>,
-    mir: &'a Mir<'tcx>,
+    mir: &'a Body<'tcx>,
 }
 
 impl<'a, 'tcx: 'a, O> DataflowAnalysis<'a, 'tcx, O> where O: BitDenotation<'tcx>
@@ -393,7 +393,7 @@ impl<'a, 'tcx: 'a, O> DataflowAnalysis<'a, 'tcx, O> where O: BitDenotation<'tcx>
         DataflowResults(self.flow_state)
     }
 
-    pub fn mir(&self) -> &'a Mir<'tcx> { self.mir }
+    pub fn mir(&self) -> &'a Body<'tcx> { self.mir }
 }
 
 pub struct DataflowResults<'tcx, O>(pub(crate) DataflowState<'tcx, O>) where O: BitDenotation<'tcx>;
@@ -697,7 +697,7 @@ pub trait BitDenotation<'tcx>: BitSetOperator {
 
 impl<'a, 'tcx, D> DataflowAnalysis<'a, 'tcx, D> where D: BitDenotation<'tcx>
 {
-    pub fn new(mir: &'a Mir<'tcx>,
+    pub fn new(mir: &'a Body<'tcx>,
                dead_unwinds: &'a BitSet<mir::BasicBlock>,
                denotation: D) -> Self where D: InitialFlow {
         let bits_per_block = denotation.bits_per_block();
diff --git a/src/librustc_mir/dataflow/move_paths/builder.rs b/src/librustc_mir/dataflow/move_paths/builder.rs
index ab0a2d87302..816a2696253 100644
--- a/src/librustc_mir/dataflow/move_paths/builder.rs
+++ b/src/librustc_mir/dataflow/move_paths/builder.rs
@@ -13,14 +13,14 @@ use super::{MoveError, InitIndex, Init, InitLocation, LookupResult, InitKind};
 use super::IllegalMoveOriginKind::*;
 
 struct MoveDataBuilder<'a, 'gcx: 'tcx, 'tcx: 'a> {
-    mir: &'a Mir<'tcx>,
+    mir: &'a Body<'tcx>,
     tcx: TyCtxt<'a, 'gcx, 'tcx>,
     data: MoveData<'tcx>,
     errors: Vec<(Place<'tcx>, MoveError<'tcx>)>,
 }
 
 impl<'a, 'gcx, 'tcx> MoveDataBuilder<'a, 'gcx, 'tcx> {
-    fn new(mir: &'a Mir<'tcx>, tcx: TyCtxt<'a, 'gcx, 'tcx>) -> Self {
+    fn new(mir: &'a Body<'tcx>, tcx: TyCtxt<'a, 'gcx, 'tcx>) -> Self {
         let mut move_paths = IndexVec::new();
         let mut path_map = IndexVec::new();
         let mut init_path_map = IndexVec::new();
@@ -203,7 +203,7 @@ impl<'a, 'gcx, 'tcx> MoveDataBuilder<'a, 'gcx, 'tcx> {
 }
 
 pub(super) fn gather_moves<'a, 'gcx, 'tcx>(
-    mir: &Mir<'tcx>,
+    mir: &Body<'tcx>,
     tcx: TyCtxt<'a, 'gcx, 'tcx>
 ) -> Result<MoveData<'tcx>, (MoveData<'tcx>, Vec<(Place<'tcx>, MoveError<'tcx>)>)> {
     let mut builder = MoveDataBuilder::new(mir, tcx);
diff --git a/src/librustc_mir/dataflow/move_paths/mod.rs b/src/librustc_mir/dataflow/move_paths/mod.rs
index 7aaf44a8a89..0d20040d0d2 100644
--- a/src/librustc_mir/dataflow/move_paths/mod.rs
+++ b/src/librustc_mir/dataflow/move_paths/mod.rs
@@ -138,7 +138,7 @@ impl<T> IndexMut<Location> for LocationMap<T> {
 }
 
 impl<T> LocationMap<T> where T: Default + Clone {
-    fn new(mir: &Mir<'_>) -> Self {
+    fn new(mir: &Body<'_>) -> Self {
         LocationMap {
             map: mir.basic_blocks().iter().map(|block| {
                 vec![T::default(); block.statements.len()+1]
@@ -205,7 +205,7 @@ impl fmt::Debug for Init {
 }
 
 impl Init {
-    crate fn span<'gcx>(&self, mir: &Mir<'gcx>) -> Span {
+    crate fn span<'gcx>(&self, mir: &Body<'gcx>) -> Span {
         match self.location {
             InitLocation::Argument(local) => mir.local_decls[local].source_info.span,
             InitLocation::Statement(location) => mir.source_info(location).span,
@@ -306,7 +306,7 @@ impl<'tcx> MoveError<'tcx> {
 }
 
 impl<'a, 'gcx, 'tcx> MoveData<'tcx> {
-    pub fn gather_moves(mir: &Mir<'tcx>, tcx: TyCtxt<'a, 'gcx, 'tcx>)
+    pub fn gather_moves(mir: &Body<'tcx>, tcx: TyCtxt<'a, 'gcx, 'tcx>)
                         -> Result<Self, (Self, Vec<(Place<'tcx>, MoveError<'tcx>)>)> {
         builder::gather_moves(mir, tcx)
     }
diff --git a/src/librustc_mir/hair/cx/mod.rs b/src/librustc_mir/hair/cx/mod.rs
index 9798d7e8a16..80f64e85f9c 100644
--- a/src/librustc_mir/hair/cx/mod.rs
+++ b/src/librustc_mir/hair/cx/mod.rs
@@ -44,7 +44,7 @@ pub struct Cx<'a, 'gcx: 'a + 'tcx, 'tcx: 'a> {
     /// Whether this constant/function needs overflow checks.
     check_overflow: bool,
 
-    /// See field with the same name on `Mir`.
+    /// See field with the same name on `mir::Body`.
     control_flow_destroyed: Vec<(Span, String)>,
 }
 
diff --git a/src/librustc_mir/interpret/eval_context.rs b/src/librustc_mir/interpret/eval_context.rs
index 2f89740876d..d3cbd2bcc03 100644
--- a/src/librustc_mir/interpret/eval_context.rs
+++ b/src/librustc_mir/interpret/eval_context.rs
@@ -53,7 +53,7 @@ pub struct Frame<'mir, 'tcx: 'mir, Tag=(), Extra=()> {
     // Function and callsite information
     ////////////////////////////////////////////////////////////////////////////////
     /// The MIR for the function called on this frame.
-    pub mir: &'mir mir::Mir<'tcx>,
+    pub mir: &'mir mir::Body<'tcx>,
 
     /// The def_id and substs of the current function.
     pub instance: ty::Instance<'tcx>,
@@ -244,7 +244,7 @@ impl<'a, 'mir, 'tcx: 'mir, M: Machine<'a, 'mir, 'tcx>> InterpretCx<'a, 'mir, 'tc
     }
 
     #[inline(always)]
-    pub(super) fn mir(&self) -> &'mir mir::Mir<'tcx> {
+    pub(super) fn mir(&self) -> &'mir mir::Body<'tcx> {
         self.frame().mir
     }
 
@@ -294,7 +294,7 @@ impl<'a, 'mir, 'tcx: 'mir, M: Machine<'a, 'mir, 'tcx>> InterpretCx<'a, 'mir, 'tc
     pub fn load_mir(
         &self,
         instance: ty::InstanceDef<'tcx>,
-    ) -> EvalResult<'tcx, &'tcx mir::Mir<'tcx>> {
+    ) -> EvalResult<'tcx, &'tcx mir::Body<'tcx>> {
         // do not continue if typeck errors occurred (can only occur in local crate)
         let did = instance.def_id();
         if did.is_local()
@@ -472,7 +472,7 @@ impl<'a, 'mir, 'tcx: 'mir, M: Machine<'a, 'mir, 'tcx>> InterpretCx<'a, 'mir, 'tc
         &mut self,
         instance: ty::Instance<'tcx>,
         span: source_map::Span,
-        mir: &'mir mir::Mir<'tcx>,
+        mir: &'mir mir::Body<'tcx>,
         return_place: Option<PlaceTy<'tcx, M::PointerTag>>,
         return_to_block: StackPopCleanup,
     ) -> EvalResult<'tcx> {
diff --git a/src/librustc_mir/interpret/machine.rs b/src/librustc_mir/interpret/machine.rs
index 288ffbf3cd6..873c2d2ec60 100644
--- a/src/librustc_mir/interpret/machine.rs
+++ b/src/librustc_mir/interpret/machine.rs
@@ -117,7 +117,7 @@ pub trait Machine<'a, 'mir, 'tcx>: Sized {
         args: &[OpTy<'tcx, Self::PointerTag>],
         dest: Option<PlaceTy<'tcx, Self::PointerTag>>,
         ret: Option<mir::BasicBlock>,
-    ) -> EvalResult<'tcx, Option<&'mir mir::Mir<'tcx>>>;
+    ) -> EvalResult<'tcx, Option<&'mir mir::Body<'tcx>>>;
 
     /// Directly process an intrinsic without pushing a stack frame.
     /// If this returns successfully, the engine will take care of jumping to the next block.
diff --git a/src/librustc_mir/lints.rs b/src/librustc_mir/lints.rs
index 51ceb2a01c3..cbfc8993471 100644
--- a/src/librustc_mir/lints.rs
+++ b/src/librustc_mir/lints.rs
@@ -3,12 +3,12 @@ use rustc::hir::def_id::DefId;
 use rustc::hir::intravisit::FnKind;
 use rustc::hir::map::blocks::FnLikeNode;
 use rustc::lint::builtin::UNCONDITIONAL_RECURSION;
-use rustc::mir::{self, Mir, TerminatorKind};
+use rustc::mir::{self, Body, TerminatorKind};
 use rustc::ty::{self, AssocItem, AssocItemContainer, Instance, TyCtxt};
 use rustc::ty::subst::InternalSubsts;
 
 pub fn check(tcx: TyCtxt<'a, 'tcx, 'tcx>,
-             mir: &Mir<'tcx>,
+             mir: &Body<'tcx>,
              def_id: DefId) {
     let hir_id = tcx.hir().as_local_hir_id(def_id).unwrap();
 
@@ -19,7 +19,7 @@ pub fn check(tcx: TyCtxt<'a, 'tcx, 'tcx>,
 
 fn check_fn_for_unconditional_recursion(tcx: TyCtxt<'a, 'tcx, 'tcx>,
                                         fn_kind: FnKind<'_>,
-                                        mir: &Mir<'tcx>,
+                                        mir: &Body<'tcx>,
                                         def_id: DefId) {
     if let FnKind::Closure(_) = fn_kind {
         // closures can't recur, so they don't matter.
diff --git a/src/librustc_mir/monomorphize/collector.rs b/src/librustc_mir/monomorphize/collector.rs
index b90db7646d4..c1131336f36 100644
--- a/src/librustc_mir/monomorphize/collector.rs
+++ b/src/librustc_mir/monomorphize/collector.rs
@@ -517,7 +517,7 @@ fn check_type_length_limit<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
 
 struct MirNeighborCollector<'a, 'tcx: 'a> {
     tcx: TyCtxt<'a, 'tcx, 'tcx>,
-    mir: &'a mir::Mir<'tcx>,
+    mir: &'a mir::Body<'tcx>,
     output: &'a mut Vec<MonoItem<'tcx>>,
     param_substs: SubstsRef<'tcx>,
 }
@@ -1218,7 +1218,7 @@ fn collect_neighbours<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
         mir: &mir,
         output,
         param_substs: instance.substs,
-    }.visit_mir(&mir);
+    }.visit_body(&mir);
     let param_env = ty::ParamEnv::reveal_all();
     for i in 0..mir.promoted.len() {
         use rustc_data_structures::indexed_vec::Idx;
diff --git a/src/librustc_mir/shim.rs b/src/librustc_mir/shim.rs
index 12a1659e043..087f8779b69 100644
--- a/src/librustc_mir/shim.rs
+++ b/src/librustc_mir/shim.rs
@@ -28,7 +28,7 @@ pub fn provide(providers: &mut Providers<'_>) {
 
 fn make_shim<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
                        instance: ty::InstanceDef<'tcx>)
-                       -> &'tcx Mir<'tcx>
+                       -> &'tcx Body<'tcx>
 {
     debug!("make_shim({:?})", instance);
 
@@ -169,7 +169,7 @@ fn local_decls_for_sig<'tcx>(sig: &ty::FnSig<'tcx>, span: Span)
 fn build_drop_shim<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
                              def_id: DefId,
                              ty: Option<Ty<'tcx>>)
-                             -> Mir<'tcx>
+                             -> Body<'tcx>
 {
     debug!("build_drop_shim(def_id={:?}, ty={:?})", def_id, ty);
 
@@ -202,7 +202,7 @@ fn build_drop_shim<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
     block(&mut blocks, TerminatorKind::Goto { target: return_block });
     block(&mut blocks, TerminatorKind::Return);
 
-    let mut mir = Mir::new(
+    let mut mir = Body::new(
         blocks,
         IndexVec::from_elem_n(
             SourceScopeData { span: span, parent_scope: None }, 1
@@ -256,7 +256,7 @@ fn build_drop_shim<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
 }
 
 pub struct DropShimElaborator<'a, 'tcx: 'a> {
-    pub mir: &'a Mir<'tcx>,
+    pub mir: &'a Body<'tcx>,
     pub patch: MirPatch<'tcx>,
     pub tcx: TyCtxt<'a, 'tcx, 'tcx>,
     pub param_env: ty::ParamEnv<'tcx>,
@@ -272,7 +272,7 @@ impl<'a, 'tcx> DropElaborator<'a, 'tcx> for DropShimElaborator<'a, 'tcx> {
     type Path = ();
 
     fn patch(&mut self) -> &mut MirPatch<'tcx> { &mut self.patch }
-    fn mir(&self) -> &'a Mir<'tcx> { self.mir }
+    fn mir(&self) -> &'a Body<'tcx> { self.mir }
     fn tcx(&self) -> TyCtxt<'a, 'tcx, 'tcx> { self.tcx }
     fn param_env(&self) -> ty::ParamEnv<'tcx> { self.param_env }
 
@@ -309,7 +309,7 @@ impl<'a, 'tcx> DropElaborator<'a, 'tcx> for DropShimElaborator<'a, 'tcx> {
 fn build_clone_shim<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
                               def_id: DefId,
                               self_ty: Ty<'tcx>)
-                              -> Mir<'tcx>
+                              -> Body<'tcx>
 {
     debug!("build_clone_shim(def_id={:?})", def_id);
 
@@ -371,8 +371,8 @@ impl<'a, 'tcx> CloneShimBuilder<'a, 'tcx> {
         }
     }
 
-    fn into_mir(self) -> Mir<'tcx> {
-        Mir::new(
+    fn into_mir(self) -> Body<'tcx> {
+        Body::new(
             self.blocks,
             IndexVec::from_elem_n(
                 SourceScopeData { span: self.span, parent_scope: None }, 1
@@ -696,7 +696,7 @@ fn build_call_shim<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
                              rcvr_adjustment: Adjustment,
                              call_kind: CallKind,
                              untuple_args: Option<&[Ty<'tcx>]>)
-                             -> Mir<'tcx>
+                             -> Body<'tcx>
 {
     debug!("build_call_shim(def_id={:?}, rcvr_adjustment={:?}, \
             call_kind={:?}, untuple_args={:?})",
@@ -821,7 +821,7 @@ fn build_call_shim<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
         block(&mut blocks, vec![], TerminatorKind::Resume, true);
     }
 
-    let mut mir = Mir::new(
+    let mut mir = Body::new(
         blocks,
         IndexVec::from_elem_n(
             SourceScopeData { span: span, parent_scope: None }, 1
@@ -846,7 +846,7 @@ pub fn build_adt_ctor<'a, 'gcx, 'tcx>(infcx: &infer::InferCtxt<'a, 'gcx, 'tcx>,
                                       ctor_id: hir::HirId,
                                       fields: &[hir::StructField],
                                       span: Span)
-                                      -> Mir<'tcx>
+                                      -> Body<'tcx>
 {
     let tcx = infcx.tcx;
     let gcx = tcx.global_tcx();
@@ -900,7 +900,7 @@ pub fn build_adt_ctor<'a, 'gcx, 'tcx>(infcx: &infer::InferCtxt<'a, 'gcx, 'tcx>,
         is_cleanup: false
     };
 
-    Mir::new(
+    Body::new(
         IndexVec::from_elem_n(start_block, 1),
         IndexVec::from_elem_n(
             SourceScopeData { span: span, parent_scope: None }, 1
diff --git a/src/librustc_mir/transform/add_call_guards.rs b/src/librustc_mir/transform/add_call_guards.rs
index 88042d64e96..712e9b1fe25 100644
--- a/src/librustc_mir/transform/add_call_guards.rs
+++ b/src/librustc_mir/transform/add_call_guards.rs
@@ -34,13 +34,13 @@ impl MirPass for AddCallGuards {
     fn run_pass<'a, 'tcx>(&self,
                           _tcx: TyCtxt<'a, 'tcx, 'tcx>,
                           _src: MirSource<'tcx>,
-                          mir: &mut Mir<'tcx>) {
+                          mir: &mut Body<'tcx>) {
         self.add_call_guards(mir);
     }
 }
 
 impl AddCallGuards {
-    pub fn add_call_guards(&self, mir: &mut Mir<'_>) {
+    pub fn add_call_guards(&self, mir: &mut Body<'_>) {
         let pred_count: IndexVec<_, _> =
             mir.predecessors().iter().map(|ps| ps.len()).collect();
 
diff --git a/src/librustc_mir/transform/add_moves_for_packed_drops.rs b/src/librustc_mir/transform/add_moves_for_packed_drops.rs
index b6436ec70ee..f7a4bf75954 100644
--- a/src/librustc_mir/transform/add_moves_for_packed_drops.rs
+++ b/src/librustc_mir/transform/add_moves_for_packed_drops.rs
@@ -43,7 +43,7 @@ impl MirPass for AddMovesForPackedDrops {
     fn run_pass<'a, 'tcx>(&self,
                           tcx: TyCtxt<'a, 'tcx, 'tcx>,
                           src: MirSource<'tcx>,
-                          mir: &mut Mir<'tcx>)
+                          mir: &mut Body<'tcx>)
     {
         debug!("add_moves_for_packed_drops({:?} @ {:?})", src, mir.span);
         add_moves_for_packed_drops(tcx, mir, src.def_id());
@@ -52,7 +52,7 @@ impl MirPass for AddMovesForPackedDrops {
 
 pub fn add_moves_for_packed_drops<'a, 'tcx>(
     tcx: TyCtxt<'a, 'tcx, 'tcx>,
-    mir: &mut Mir<'tcx>,
+    mir: &mut Body<'tcx>,
     def_id: DefId)
 {
     let patch = add_moves_for_packed_drops_patch(tcx, mir, def_id);
@@ -61,7 +61,7 @@ pub fn add_moves_for_packed_drops<'a, 'tcx>(
 
 fn add_moves_for_packed_drops_patch<'a, 'tcx>(
     tcx: TyCtxt<'a, 'tcx, 'tcx>,
-    mir: &Mir<'tcx>,
+    mir: &Body<'tcx>,
     def_id: DefId)
     -> MirPatch<'tcx>
 {
@@ -92,7 +92,7 @@ fn add_moves_for_packed_drops_patch<'a, 'tcx>(
 
 fn add_move_for_packed_drop<'a, 'tcx>(
     tcx: TyCtxt<'a, 'tcx, 'tcx>,
-    mir: &Mir<'tcx>,
+    mir: &Body<'tcx>,
     patch: &mut MirPatch<'tcx>,
     terminator: &Terminator<'tcx>,
     loc: Location,
diff --git a/src/librustc_mir/transform/add_retag.rs b/src/librustc_mir/transform/add_retag.rs
index 32c9953ee9e..23319f70551 100644
--- a/src/librustc_mir/transform/add_retag.rs
+++ b/src/librustc_mir/transform/add_retag.rs
@@ -77,7 +77,7 @@ impl MirPass for AddRetag {
     fn run_pass<'a, 'tcx>(&self,
                           tcx: TyCtxt<'a, 'tcx, 'tcx>,
                           _src: MirSource<'tcx>,
-                          mir: &mut Mir<'tcx>)
+                          mir: &mut Body<'tcx>)
     {
         if !tcx.sess.opts.debugging_opts.mir_emit_retag {
             return;
diff --git a/src/librustc_mir/transform/check_unsafety.rs b/src/librustc_mir/transform/check_unsafety.rs
index 394d1f06029..8ec8a8fa12e 100644
--- a/src/librustc_mir/transform/check_unsafety.rs
+++ b/src/librustc_mir/transform/check_unsafety.rs
@@ -19,7 +19,7 @@ use std::ops::Bound;
 use crate::util;
 
 pub struct UnsafetyChecker<'a, 'tcx: 'a> {
-    mir: &'a Mir<'tcx>,
+    mir: &'a Body<'tcx>,
     const_context: bool,
     min_const_fn: bool,
     source_scope_local_data: &'a IndexVec<SourceScope, SourceScopeLocalData>,
@@ -36,7 +36,7 @@ impl<'a, 'gcx, 'tcx> UnsafetyChecker<'a, 'tcx> {
     fn new(
         const_context: bool,
         min_const_fn: bool,
-        mir: &'a Mir<'tcx>,
+        mir: &'a Body<'tcx>,
         source_scope_local_data: &'a IndexVec<SourceScope, SourceScopeLocalData>,
         tcx: TyCtxt<'a, 'tcx, 'tcx>,
         param_env: ty::ParamEnv<'tcx>,
@@ -538,7 +538,7 @@ fn unsafety_check_result<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>, def_id: DefId)
     let mut checker = UnsafetyChecker::new(
         const_context, min_const_fn,
         mir, source_scope_local_data, tcx, param_env);
-    checker.visit_mir(mir);
+    checker.visit_body(mir);
 
     check_unused_unsafe(tcx, def_id, &checker.used_unsafe, &mut checker.inherited_blocks);
     UnsafetyCheckResult {
diff --git a/src/librustc_mir/transform/cleanup_post_borrowck.rs b/src/librustc_mir/transform/cleanup_post_borrowck.rs
index 64fd0b13656..63a1b059d90 100644
--- a/src/librustc_mir/transform/cleanup_post_borrowck.rs
+++ b/src/librustc_mir/transform/cleanup_post_borrowck.rs
@@ -16,7 +16,7 @@
 //! [`FakeRead`]: rustc::mir::StatementKind::FakeRead
 //! [`Nop`]: rustc::mir::StatementKind::Nop
 
-use rustc::mir::{BorrowKind, Rvalue, Location, Mir};
+use rustc::mir::{BorrowKind, Rvalue, Location, Body};
 use rustc::mir::{Statement, StatementKind};
 use rustc::mir::visit::MutVisitor;
 use rustc::ty::TyCtxt;
@@ -30,9 +30,9 @@ impl MirPass for CleanupNonCodegenStatements {
     fn run_pass<'a, 'tcx>(&self,
                           _tcx: TyCtxt<'a, 'tcx, 'tcx>,
                           _source: MirSource<'tcx>,
-                          mir: &mut Mir<'tcx>) {
+                          mir: &mut Body<'tcx>) {
         let mut delete = DeleteNonCodegenStatements;
-        delete.visit_mir(mir);
+        delete.visit_body(mir);
     }
 }
 
diff --git a/src/librustc_mir/transform/const_prop.rs b/src/librustc_mir/transform/const_prop.rs
index c46b439f4d3..728ea41a9d8 100644
--- a/src/librustc_mir/transform/const_prop.rs
+++ b/src/librustc_mir/transform/const_prop.rs
@@ -3,7 +3,7 @@
 
 use rustc::hir::def::DefKind;
 use rustc::mir::{
-    AggregateKind, Constant, Location, Place, PlaceBase, Mir, Operand, Rvalue, Local,
+    AggregateKind, Constant, Location, Place, PlaceBase, Body, Operand, Rvalue, Local,
     NullOp, UnOp, StatementKind, Statement, LocalKind, Static, StaticKind,
     TerminatorKind, Terminator,  ClearCrossCrate, SourceInfo, BinOp, ProjectionElem,
     SourceScope, SourceScopeLocalData, LocalDecl, Promoted,
@@ -33,7 +33,7 @@ impl MirPass for ConstProp {
     fn run_pass<'a, 'tcx>(&self,
                           tcx: TyCtxt<'a, 'tcx, 'tcx>,
                           source: MirSource<'tcx>,
-                          mir: &mut Mir<'tcx>) {
+                          mir: &mut Body<'tcx>) {
         // will be evaluated by miri and produce its errors there
         if source.promoted.is_some() {
             return;
@@ -63,7 +63,7 @@ impl MirPass for ConstProp {
         // That would require an uniform one-def no-mutation analysis
         // and RPO (or recursing when needing the value of a local).
         let mut optimization_finder = ConstPropagator::new(mir, tcx, source);
-        optimization_finder.visit_mir(mir);
+        optimization_finder.visit_body(mir);
 
         // put back the data we stole from `mir`
         std::mem::replace(
@@ -91,7 +91,7 @@ struct ConstPropagator<'a, 'mir, 'tcx:'a+'mir> {
     param_env: ParamEnv<'tcx>,
     source_scope_local_data: ClearCrossCrate<IndexVec<SourceScope, SourceScopeLocalData>>,
     local_decls: IndexVec<Local, LocalDecl<'tcx>>,
-    promoted: IndexVec<Promoted, Mir<'tcx>>,
+    promoted: IndexVec<Promoted, Body<'tcx>>,
 }
 
 impl<'a, 'b, 'tcx> LayoutOf for ConstPropagator<'a, 'b, 'tcx> {
@@ -119,7 +119,7 @@ impl<'a, 'b, 'tcx> HasTyCtxt<'tcx> for ConstPropagator<'a, 'b, 'tcx> {
 
 impl<'a, 'mir, 'tcx> ConstPropagator<'a, 'mir, 'tcx> {
     fn new(
-        mir: &mut Mir<'tcx>,
+        mir: &mut Body<'tcx>,
         tcx: TyCtxt<'a, 'tcx, 'tcx>,
         source: MirSource<'tcx>,
     ) -> ConstPropagator<'a, 'mir, 'tcx> {
@@ -143,7 +143,7 @@ impl<'a, 'mir, 'tcx> ConstPropagator<'a, 'mir, 'tcx> {
             can_const_prop,
             places: IndexVec::from_elem(None, &mir.local_decls),
             source_scope_local_data,
-            //FIXME(wesleywiser) we can't steal this because `Visitor::super_visit_mir()` needs it
+            //FIXME(wesleywiser) we can't steal this because `Visitor::super_visit_body()` needs it
             local_decls: mir.local_decls.clone(),
             promoted,
         }
@@ -569,7 +569,7 @@ struct CanConstProp {
 
 impl CanConstProp {
     /// returns true if `local` can be propagated
-    fn check(mir: &Mir<'_>) -> IndexVec<Local, bool> {
+    fn check(mir: &Body<'_>) -> IndexVec<Local, bool> {
         let mut cpv = CanConstProp {
             can_const_prop: IndexVec::from_elem(true, &mir.local_decls),
             found_assignment: IndexVec::from_elem(false, &mir.local_decls),
@@ -586,7 +586,7 @@ impl CanConstProp {
                 trace!("local {:?} can't be propagated because it's not a temporary", local);
             }
         }
-        cpv.visit_mir(mir);
+        cpv.visit_body(mir);
         cpv.can_const_prop
     }
 }
diff --git a/src/librustc_mir/transform/copy_prop.rs b/src/librustc_mir/transform/copy_prop.rs
index dfe2e991ba9..c48d2d29571 100644
--- a/src/librustc_mir/transform/copy_prop.rs
+++ b/src/librustc_mir/transform/copy_prop.rs
@@ -20,7 +20,7 @@
 //! future.
 
 use rustc::mir::{
-    Constant, Local, LocalKind, Location, Place, PlaceBase, Mir, Operand, Rvalue, StatementKind
+    Constant, Local, LocalKind, Location, Place, PlaceBase, Body, Operand, Rvalue, StatementKind
 };
 use rustc::mir::visit::MutVisitor;
 use rustc::ty::TyCtxt;
@@ -33,7 +33,7 @@ impl MirPass for CopyPropagation {
     fn run_pass<'a, 'tcx>(&self,
                           tcx: TyCtxt<'a, 'tcx, 'tcx>,
                           _source: MirSource<'tcx>,
-                          mir: &mut Mir<'tcx>) {
+                          mir: &mut Body<'tcx>) {
         // We only run when the MIR optimization level is > 1.
         // This avoids a slow pass, and messing up debug info.
         if tcx.sess.opts.debugging_opts.mir_opt_level <= 1 {
@@ -135,7 +135,7 @@ impl MirPass for CopyPropagation {
 }
 
 fn eliminate_self_assignments(
-    mir: &mut Mir<'_>,
+    mir: &mut Body<'_>,
     def_use_analysis: &DefUseAnalysis,
 ) -> bool {
     let mut changed = false;
@@ -177,7 +177,7 @@ enum Action<'tcx> {
 }
 
 impl<'tcx> Action<'tcx> {
-    fn local_copy(mir: &Mir<'tcx>, def_use_analysis: &DefUseAnalysis, src_place: &Place<'tcx>)
+    fn local_copy(mir: &Body<'tcx>, def_use_analysis: &DefUseAnalysis, src_place: &Place<'tcx>)
                   -> Option<Action<'tcx>> {
         // The source must be a local.
         let src_local = if let Place::Base(PlaceBase::Local(local)) = *src_place {
@@ -232,7 +232,7 @@ impl<'tcx> Action<'tcx> {
     }
 
     fn perform(self,
-               mir: &mut Mir<'tcx>,
+               mir: &mut Body<'tcx>,
                def_use_analysis: &DefUseAnalysis,
                dest_local: Local,
                location: Location)
diff --git a/src/librustc_mir/transform/deaggregator.rs b/src/librustc_mir/transform/deaggregator.rs
index 9215356daa4..7da37f956ce 100644
--- a/src/librustc_mir/transform/deaggregator.rs
+++ b/src/librustc_mir/transform/deaggregator.rs
@@ -10,7 +10,7 @@ impl MirPass for Deaggregator {
     fn run_pass<'a, 'tcx>(&self,
                           tcx: TyCtxt<'a, 'tcx, 'tcx>,
                           _source: MirSource<'tcx>,
-                          mir: &mut Mir<'tcx>) {
+                          mir: &mut Body<'tcx>) {
         let (basic_blocks, local_decls) = mir.basic_blocks_and_local_decls_mut();
         let local_decls = &*local_decls;
         for bb in basic_blocks {
diff --git a/src/librustc_mir/transform/dump_mir.rs b/src/librustc_mir/transform/dump_mir.rs
index 81e48fe2dbe..ebb65094a30 100644
--- a/src/librustc_mir/transform/dump_mir.rs
+++ b/src/librustc_mir/transform/dump_mir.rs
@@ -5,7 +5,7 @@ use std::fmt;
 use std::fs::File;
 use std::io;
 
-use rustc::mir::Mir;
+use rustc::mir::Body;
 use rustc::session::config::{OutputFilenames, OutputType};
 use rustc::ty::TyCtxt;
 use crate::transform::{MirPass, MirSource};
@@ -21,7 +21,7 @@ impl MirPass for Marker {
     fn run_pass<'a, 'tcx>(&self,
                           _tcx: TyCtxt<'a, 'tcx, 'tcx>,
                           _source: MirSource<'tcx>,
-                          _mir: &mut Mir<'tcx>)
+                          _mir: &mut Body<'tcx>)
     {
     }
 }
@@ -42,7 +42,7 @@ pub fn on_mir_pass<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
                              pass_num: &dyn fmt::Display,
                              pass_name: &str,
                              source: MirSource<'tcx>,
-                             mir: &Mir<'tcx>,
+                             mir: &Body<'tcx>,
                              is_after: bool) {
     if mir_util::dump_enabled(tcx, pass_name, source) {
         mir_util::dump_mir(tcx,
diff --git a/src/librustc_mir/transform/elaborate_drops.rs b/src/librustc_mir/transform/elaborate_drops.rs
index 6320cb44248..c833af29c36 100644
--- a/src/librustc_mir/transform/elaborate_drops.rs
+++ b/src/librustc_mir/transform/elaborate_drops.rs
@@ -24,7 +24,7 @@ impl MirPass for ElaborateDrops {
     fn run_pass<'a, 'tcx>(&self,
                           tcx: TyCtxt<'a, 'tcx, 'tcx>,
                           src: MirSource<'tcx>,
-                          mir: &mut Mir<'tcx>)
+                          mir: &mut Body<'tcx>)
     {
         debug!("elaborate_drops({:?} @ {:?})", src, mir.span);
 
@@ -79,7 +79,7 @@ impl MirPass for ElaborateDrops {
 /// that can't drop anything.
 fn find_dead_unwinds<'a, 'tcx>(
     tcx: TyCtxt<'a, 'tcx, 'tcx>,
-    mir: &Mir<'tcx>,
+    mir: &Body<'tcx>,
     def_id: hir::def_id::DefId,
     env: &MoveDataParamEnv<'tcx, 'tcx>)
     -> BitSet<BasicBlock>
@@ -143,7 +143,7 @@ struct InitializationData {
 impl InitializationData {
     fn apply_location<'a,'tcx>(&mut self,
                                tcx: TyCtxt<'a, 'tcx, 'tcx>,
-                               mir: &Mir<'tcx>,
+                               mir: &Body<'tcx>,
                                env: &MoveDataParamEnv<'tcx, 'tcx>,
                                loc: Location)
     {
@@ -186,7 +186,7 @@ impl<'a, 'b, 'tcx> DropElaborator<'a, 'tcx> for Elaborator<'a, 'b, 'tcx> {
         &mut self.ctxt.patch
     }
 
-    fn mir(&self) -> &'a Mir<'tcx> {
+    fn mir(&self) -> &'a Body<'tcx> {
         self.ctxt.mir
     }
 
@@ -291,7 +291,7 @@ impl<'a, 'b, 'tcx> DropElaborator<'a, 'tcx> for Elaborator<'a, 'b, 'tcx> {
 
 struct ElaborateDropsCtxt<'a, 'tcx: 'a> {
     tcx: TyCtxt<'a, 'tcx, 'tcx>,
-    mir: &'a Mir<'tcx>,
+    mir: &'a Body<'tcx>,
     env: &'a MoveDataParamEnv<'tcx, 'tcx>,
     flow_inits: DataflowResults<'tcx, MaybeInitializedPlaces<'a, 'tcx, 'tcx>>,
     flow_uninits:  DataflowResults<'tcx, MaybeUninitializedPlaces<'a, 'tcx, 'tcx>>,
diff --git a/src/librustc_mir/transform/erase_regions.rs b/src/librustc_mir/transform/erase_regions.rs
index 7c2ff94b75d..ffc5bba6d60 100644
--- a/src/librustc_mir/transform/erase_regions.rs
+++ b/src/librustc_mir/transform/erase_regions.rs
@@ -53,7 +53,7 @@ impl MirPass for EraseRegions {
     fn run_pass<'a, 'tcx>(&self,
                           tcx: TyCtxt<'a, 'tcx, 'tcx>,
                           _: MirSource<'tcx>,
-                          mir: &mut Mir<'tcx>) {
-        EraseRegionsVisitor::new(tcx).visit_mir(mir);
+                          mir: &mut Body<'tcx>) {
+        EraseRegionsVisitor::new(tcx).visit_body(mir);
     }
 }
diff --git a/src/librustc_mir/transform/generator.rs b/src/librustc_mir/transform/generator.rs
index ab2f2933a96..f36ede4e8d9 100644
--- a/src/librustc_mir/transform/generator.rs
+++ b/src/librustc_mir/transform/generator.rs
@@ -210,7 +210,7 @@ impl<'a, 'tcx> TransformVisitor<'a, 'tcx> {
     }
 
     // Create a statement which reads the discriminant into a temporary
-    fn get_discr(&self, mir: &mut Mir<'tcx>) -> (Statement<'tcx>, Place<'tcx>) {
+    fn get_discr(&self, mir: &mut Body<'tcx>) -> (Statement<'tcx>, Place<'tcx>) {
         let temp_decl = LocalDecl::new_internal(self.tcx.types.isize, mir.span);
         let local_decls_len = mir.local_decls.push(temp_decl);
         let temp = Place::Base(PlaceBase::Local(local_decls_len));
@@ -304,7 +304,7 @@ impl<'a, 'tcx> MutVisitor<'tcx> for TransformVisitor<'a, 'tcx> {
 fn make_generator_state_argument_indirect<'a, 'tcx>(
                 tcx: TyCtxt<'a, 'tcx, 'tcx>,
                 def_id: DefId,
-                mir: &mut Mir<'tcx>) {
+                mir: &mut Body<'tcx>) {
     let gen_ty = mir.local_decls.raw[1].ty;
 
     let region = ty::ReFree(ty::FreeRegion {
@@ -323,12 +323,12 @@ fn make_generator_state_argument_indirect<'a, 'tcx>(
     mir.local_decls.raw[1].ty = ref_gen_ty;
 
     // Add a deref to accesses of the generator state
-    DerefArgVisitor.visit_mir(mir);
+    DerefArgVisitor.visit_body(mir);
 }
 
 fn make_generator_state_argument_pinned<'a, 'tcx>(
                 tcx: TyCtxt<'a, 'tcx, 'tcx>,
-                mir: &mut Mir<'tcx>) {
+                mir: &mut Body<'tcx>) {
     let ref_gen_ty = mir.local_decls.raw[1].ty;
 
     let pin_did = tcx.lang_items().pin_type().unwrap();
@@ -340,12 +340,12 @@ fn make_generator_state_argument_pinned<'a, 'tcx>(
     mir.local_decls.raw[1].ty = pin_ref_gen_ty;
 
     // Add the Pin field access to accesses of the generator state
-    PinArgVisitor { ref_gen_ty }.visit_mir(mir);
+    PinArgVisitor { ref_gen_ty }.visit_body(mir);
 }
 
 fn replace_result_variable<'tcx>(
     ret_ty: Ty<'tcx>,
-    mir: &mut Mir<'tcx>,
+    mir: &mut Body<'tcx>,
 ) -> Local {
     let source_info = source_info(mir);
     let new_ret = LocalDecl {
@@ -366,7 +366,7 @@ fn replace_result_variable<'tcx>(
     RenameLocalVisitor {
         from: RETURN_PLACE,
         to: new_ret_local,
-    }.visit_mir(mir);
+    }.visit_body(mir);
 
     new_ret_local
 }
@@ -387,7 +387,7 @@ impl<'tcx> Visitor<'tcx> for StorageIgnored {
 
 fn locals_live_across_suspend_points(
     tcx: TyCtxt<'a, 'tcx, 'tcx>,
-    mir: &Mir<'tcx>,
+    mir: &Body<'tcx>,
     source: MirSource<'tcx>,
     movable: bool,
 ) -> (
@@ -408,7 +408,7 @@ fn locals_live_across_suspend_points(
     // Find the MIR locals which do not use StorageLive/StorageDead statements.
     // The storage of these locals are always live.
     let mut ignored = StorageIgnored(BitSet::new_filled(mir.local_decls.len()));
-    ignored.visit_mir(mir);
+    ignored.visit_body(mir);
 
     // Calculate the MIR locals which have been previously
     // borrowed (even if they are still active).
@@ -503,7 +503,7 @@ fn compute_layout<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
                             upvars: &Vec<Ty<'tcx>>,
                             interior: Ty<'tcx>,
                             movable: bool,
-                            mir: &mut Mir<'tcx>)
+                            mir: &mut Body<'tcx>)
     -> (FxHashMap<Local, (Ty<'tcx>, VariantIdx, usize)>,
         GeneratorLayout<'tcx>,
         FxHashMap<BasicBlock, liveness::LiveVarSet>)
@@ -576,7 +576,7 @@ fn compute_layout<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
     (remap, layout, storage_liveness)
 }
 
-fn insert_switch<'a, 'tcx>(mir: &mut Mir<'tcx>,
+fn insert_switch<'a, 'tcx>(mir: &mut Body<'tcx>,
                            cases: Vec<(usize, BasicBlock)>,
                            transform: &TransformVisitor<'a, 'tcx>,
                            default: TerminatorKind<'tcx>) {
@@ -608,7 +608,7 @@ fn insert_switch<'a, 'tcx>(mir: &mut Mir<'tcx>,
 
 fn elaborate_generator_drops<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
                                        def_id: DefId,
-                                       mir: &mut Mir<'tcx>) {
+                                       mir: &mut Body<'tcx>) {
     use crate::util::elaborate_drops::{elaborate_drop, Unwind};
     use crate::util::patch::MirPatch;
     use crate::shim::DropShimElaborator;
@@ -663,8 +663,8 @@ fn create_generator_drop_shim<'a, 'tcx>(
                 def_id: DefId,
                 source: MirSource<'tcx>,
                 gen_ty: Ty<'tcx>,
-                mir: &Mir<'tcx>,
-                drop_clean: BasicBlock) -> Mir<'tcx> {
+                mir: &Body<'tcx>,
+                drop_clean: BasicBlock) -> Body<'tcx> {
     let mut mir = mir.clone();
 
     let source_info = source_info(&mir);
@@ -734,7 +734,7 @@ fn create_generator_drop_shim<'a, 'tcx>(
     mir
 }
 
-fn insert_term_block<'tcx>(mir: &mut Mir<'tcx>, kind: TerminatorKind<'tcx>) -> BasicBlock {
+fn insert_term_block<'tcx>(mir: &mut Body<'tcx>, kind: TerminatorKind<'tcx>) -> BasicBlock {
     let term_block = BasicBlock::new(mir.basic_blocks().len());
     let source_info = source_info(mir);
     mir.basic_blocks_mut().push(BasicBlockData {
@@ -749,7 +749,7 @@ fn insert_term_block<'tcx>(mir: &mut Mir<'tcx>, kind: TerminatorKind<'tcx>) -> B
 }
 
 fn insert_panic_block<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
-                                mir: &mut Mir<'tcx>,
+                                mir: &mut Body<'tcx>,
                                 message: AssertMessage<'tcx>) -> BasicBlock {
     let assert_block = BasicBlock::new(mir.basic_blocks().len());
     let term = TerminatorKind::Assert {
@@ -783,7 +783,7 @@ fn create_generator_resume_function<'a, 'tcx>(
         transform: TransformVisitor<'a, 'tcx>,
         def_id: DefId,
         source: MirSource<'tcx>,
-        mir: &mut Mir<'tcx>) {
+        mir: &mut Body<'tcx>) {
     // Poison the generator when it unwinds
     for block in mir.basic_blocks_mut() {
         let source_info = block.terminator().source_info;
@@ -821,14 +821,14 @@ fn create_generator_resume_function<'a, 'tcx>(
     dump_mir(tcx, None, "generator_resume", &0, source, mir, |_, _| Ok(()) );
 }
 
-fn source_info<'a, 'tcx>(mir: &Mir<'tcx>) -> SourceInfo {
+fn source_info<'a, 'tcx>(mir: &Body<'tcx>) -> SourceInfo {
     SourceInfo {
         span: mir.span,
         scope: OUTERMOST_SOURCE_SCOPE,
     }
 }
 
-fn insert_clean_drop<'a, 'tcx>(mir: &mut Mir<'tcx>) -> BasicBlock {
+fn insert_clean_drop<'a, 'tcx>(mir: &mut Body<'tcx>) -> BasicBlock {
     let return_block = insert_term_block(mir, TerminatorKind::Return);
 
     // Create a block to destroy an unresumed generators. This can only destroy upvars.
@@ -851,7 +851,7 @@ fn insert_clean_drop<'a, 'tcx>(mir: &mut Mir<'tcx>) -> BasicBlock {
     drop_clean
 }
 
-fn create_cases<'a, 'tcx, F>(mir: &mut Mir<'tcx>,
+fn create_cases<'a, 'tcx, F>(mir: &mut Body<'tcx>,
                           transform: &TransformVisitor<'a, 'tcx>,
                           target: F) -> Vec<(usize, BasicBlock)>
     where F: Fn(&SuspensionPoint) -> Option<BasicBlock> {
@@ -895,7 +895,7 @@ impl MirPass for StateTransform {
     fn run_pass<'a, 'tcx>(&self,
                     tcx: TyCtxt<'a, 'tcx, 'tcx>,
                     source: MirSource<'tcx>,
-                    mir: &mut Mir<'tcx>) {
+                    mir: &mut Body<'tcx>) {
         let yield_ty = if let Some(yield_ty) = mir.yield_ty {
             yield_ty
         } else {
@@ -959,7 +959,7 @@ impl MirPass for StateTransform {
             new_ret_local,
             discr_ty,
         };
-        transform.visit_mir(mir);
+        transform.visit_body(mir);
 
         // Update our MIR struct to reflect the changed we've made
         mir.yield_ty = None;
diff --git a/src/librustc_mir/transform/inline.rs b/src/librustc_mir/transform/inline.rs
index 782af3024ad..0fac6868f57 100644
--- a/src/librustc_mir/transform/inline.rs
+++ b/src/librustc_mir/transform/inline.rs
@@ -41,7 +41,7 @@ impl MirPass for Inline {
     fn run_pass<'a, 'tcx>(&self,
                           tcx: TyCtxt<'a, 'tcx, 'tcx>,
                           source: MirSource<'tcx>,
-                          mir: &mut Mir<'tcx>) {
+                          mir: &mut Body<'tcx>) {
         if tcx.sess.opts.debugging_opts.mir_opt_level >= 2 {
             Inliner { tcx, source }.run_pass(mir);
         }
@@ -54,7 +54,7 @@ struct Inliner<'a, 'tcx: 'a> {
 }
 
 impl<'a, 'tcx> Inliner<'a, 'tcx> {
-    fn run_pass(&self, caller_mir: &mut Mir<'tcx>) {
+    fn run_pass(&self, caller_mir: &mut Body<'tcx>) {
         // Keep a queue of callsites to try inlining on. We take
         // advantage of the fact that queries detect cycles here to
         // allow us to try and fetch the fully optimized MIR of a
@@ -171,7 +171,7 @@ impl<'a, 'tcx> Inliner<'a, 'tcx> {
     fn get_valid_function_call(&self,
                                bb: BasicBlock,
                                bb_data: &BasicBlockData<'tcx>,
-                               caller_mir: &Mir<'tcx>,
+                               caller_mir: &Body<'tcx>,
                                param_env: ParamEnv<'tcx>,
     ) -> Option<CallSite<'tcx>> {
         // Don't inline calls that are in cleanup blocks.
@@ -204,7 +204,7 @@ impl<'a, 'tcx> Inliner<'a, 'tcx> {
 
     fn consider_optimizing(&self,
                            callsite: CallSite<'tcx>,
-                           callee_mir: &Mir<'tcx>)
+                           callee_mir: &Body<'tcx>)
                            -> bool
     {
         debug!("consider_optimizing({:?})", callsite);
@@ -216,7 +216,7 @@ impl<'a, 'tcx> Inliner<'a, 'tcx> {
 
     fn should_inline(&self,
                      callsite: CallSite<'tcx>,
-                     callee_mir: &Mir<'tcx>)
+                     callee_mir: &Body<'tcx>)
                      -> bool
     {
         debug!("should_inline({:?})", callsite);
@@ -394,8 +394,8 @@ impl<'a, 'tcx> Inliner<'a, 'tcx> {
 
     fn inline_call(&self,
                    callsite: CallSite<'tcx>,
-                   caller_mir: &mut Mir<'tcx>,
-                   mut callee_mir: Mir<'tcx>) -> bool {
+                   caller_mir: &mut Body<'tcx>,
+                   mut callee_mir: Body<'tcx>) -> bool {
         let terminator = caller_mir[callsite.bb].terminator.take().unwrap();
         match terminator.kind {
             // FIXME: Handle inlining of diverging calls
@@ -531,7 +531,7 @@ impl<'a, 'tcx> Inliner<'a, 'tcx> {
         &self,
         args: Vec<Operand<'tcx>>,
         callsite: &CallSite<'tcx>,
-        caller_mir: &mut Mir<'tcx>,
+        caller_mir: &mut Body<'tcx>,
     ) -> Vec<Local> {
         let tcx = self.tcx;
 
@@ -601,7 +601,7 @@ impl<'a, 'tcx> Inliner<'a, 'tcx> {
         &self,
         arg: Operand<'tcx>,
         callsite: &CallSite<'tcx>,
-        caller_mir: &mut Mir<'tcx>,
+        caller_mir: &mut Body<'tcx>,
     ) -> Local {
         // FIXME: Analysis of the usage of the arguments to avoid
         // unnecessary temporaries.
diff --git a/src/librustc_mir/transform/instcombine.rs b/src/librustc_mir/transform/instcombine.rs
index 8187a81f0ed..1b92b1acac5 100644
--- a/src/librustc_mir/transform/instcombine.rs
+++ b/src/librustc_mir/transform/instcombine.rs
@@ -1,6 +1,7 @@
 //! Performs various peephole optimizations.
 
-use rustc::mir::{Constant, Location, Place, PlaceBase, Mir, Operand, ProjectionElem, Rvalue, Local};
+use rustc::mir::{Constant, Location, Place, PlaceBase, Body, Operand, ProjectionElem, Rvalue,
+    Local};
 use rustc::mir::visit::{MutVisitor, Visitor};
 use rustc::ty::{self, TyCtxt};
 use rustc::util::nodemap::{FxHashMap, FxHashSet};
@@ -14,7 +15,7 @@ impl MirPass for InstCombine {
     fn run_pass<'a, 'tcx>(&self,
                           tcx: TyCtxt<'a, 'tcx, 'tcx>,
                           _: MirSource<'tcx>,
-                          mir: &mut Mir<'tcx>) {
+                          mir: &mut Body<'tcx>) {
         // We only run when optimizing MIR (at any level).
         if tcx.sess.opts.debugging_opts.mir_opt_level == 0 {
             return
@@ -25,12 +26,12 @@ impl MirPass for InstCombine {
         // `Place::ty()`).
         let optimizations = {
             let mut optimization_finder = OptimizationFinder::new(mir, tcx);
-            optimization_finder.visit_mir(mir);
+            optimization_finder.visit_body(mir);
             optimization_finder.optimizations
         };
 
         // Then carry out those optimizations.
-        MutVisitor::visit_mir(&mut InstCombineVisitor { optimizations }, mir);
+        MutVisitor::visit_body(&mut InstCombineVisitor { optimizations }, mir);
     }
 }
 
@@ -63,13 +64,13 @@ impl<'tcx> MutVisitor<'tcx> for InstCombineVisitor<'tcx> {
 
 /// Finds optimization opportunities on the MIR.
 struct OptimizationFinder<'b, 'a, 'tcx:'a+'b> {
-    mir: &'b Mir<'tcx>,
+    mir: &'b Body<'tcx>,
     tcx: TyCtxt<'a, 'tcx, 'tcx>,
     optimizations: OptimizationList<'tcx>,
 }
 
 impl<'b, 'a, 'tcx:'b> OptimizationFinder<'b, 'a, 'tcx> {
-    fn new(mir: &'b Mir<'tcx>, tcx: TyCtxt<'a, 'tcx, 'tcx>) -> OptimizationFinder<'b, 'a, 'tcx> {
+    fn new(mir: &'b Body<'tcx>, tcx: TyCtxt<'a, 'tcx, 'tcx>) -> OptimizationFinder<'b, 'a, 'tcx> {
         OptimizationFinder {
             mir,
             tcx,
diff --git a/src/librustc_mir/transform/lower_128bit.rs b/src/librustc_mir/transform/lower_128bit.rs
index fd9d6bb5760..8c19637a955 100644
--- a/src/librustc_mir/transform/lower_128bit.rs
+++ b/src/librustc_mir/transform/lower_128bit.rs
@@ -13,7 +13,7 @@ impl MirPass for Lower128Bit {
     fn run_pass<'a, 'tcx>(&self,
                           tcx: TyCtxt<'a, 'tcx, 'tcx>,
                           _src: MirSource<'tcx>,
-                          mir: &mut Mir<'tcx>) {
+                          mir: &mut Body<'tcx>) {
         let debugging_override = tcx.sess.opts.debugging_opts.lower_128bit_ops;
         let target_default = tcx.sess.host.options.i128_lowering;
         if !debugging_override.unwrap_or(target_default) {
@@ -25,7 +25,7 @@ impl MirPass for Lower128Bit {
 }
 
 impl Lower128Bit {
-    fn lower_128bit_ops<'a, 'tcx>(&self, tcx: TyCtxt<'a, 'tcx, 'tcx>, mir: &mut Mir<'tcx>) {
+    fn lower_128bit_ops<'a, 'tcx>(&self, tcx: TyCtxt<'a, 'tcx, 'tcx>, mir: &mut Body<'tcx>) {
         let mut new_blocks = Vec::new();
         let cur_len = mir.basic_blocks().len();
 
diff --git a/src/librustc_mir/transform/mod.rs b/src/librustc_mir/transform/mod.rs
index b6091644157..22b96a9db47 100644
--- a/src/librustc_mir/transform/mod.rs
+++ b/src/librustc_mir/transform/mod.rs
@@ -1,6 +1,6 @@
 use crate::build;
 use rustc::hir::def_id::{CrateNum, DefId, LOCAL_CRATE};
-use rustc::mir::{Mir, MirPhase, Promoted};
+use rustc::mir::{Body, MirPhase, Promoted};
 use rustc::ty::{TyCtxt, InstanceDef};
 use rustc::ty::query::Providers;
 use rustc::ty::steal::Steal;
@@ -95,12 +95,12 @@ fn mir_keys<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>, krate: CrateNum)
     tcx.arena.alloc(set)
 }
 
-fn mir_built<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>, def_id: DefId) -> &'tcx Steal<Mir<'tcx>> {
+fn mir_built<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>, def_id: DefId) -> &'tcx Steal<Body<'tcx>> {
     let mir = build::mir_build(tcx, def_id);
     tcx.alloc_steal_mir(mir)
 }
 
-/// Where a specific Mir comes from.
+/// Where a specific `mir::Body` comes from.
 #[derive(Debug, Copy, Clone)]
 pub struct MirSource<'tcx> {
     pub instance: InstanceDef<'tcx>,
@@ -145,19 +145,19 @@ pub trait MirPass {
     fn run_pass<'a, 'tcx>(&self,
                           tcx: TyCtxt<'a, 'tcx, 'tcx>,
                           source: MirSource<'tcx>,
-                          mir: &mut Mir<'tcx>);
+                          mir: &mut Body<'tcx>);
 }
 
 pub fn run_passes(
     tcx: TyCtxt<'a, 'tcx, 'tcx>,
-    mir: &mut Mir<'tcx>,
+    mir: &mut Body<'tcx>,
     instance: InstanceDef<'tcx>,
     mir_phase: MirPhase,
     passes: &[&dyn MirPass],
 ) {
     let phase_index = mir_phase.phase_index();
 
-    let run_passes = |mir: &mut Mir<'tcx>, promoted| {
+    let run_passes = |mir: &mut Body<'tcx>, promoted| {
         if mir.phase >= mir_phase {
             return;
         }
@@ -196,7 +196,7 @@ pub fn run_passes(
     }
 }
 
-fn mir_const<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>, def_id: DefId) -> &'tcx Steal<Mir<'tcx>> {
+fn mir_const<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>, def_id: DefId) -> &'tcx Steal<Body<'tcx>> {
     // Unsafety check uses the raw mir, so make sure it is run
     let _ = tcx.unsafety_check_result(def_id);
 
@@ -210,7 +210,7 @@ fn mir_const<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>, def_id: DefId) -> &'tcx Stea
     tcx.alloc_steal_mir(mir)
 }
 
-fn mir_validated<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>, def_id: DefId) -> &'tcx Steal<Mir<'tcx>> {
+fn mir_validated<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>, def_id: DefId) -> &'tcx Steal<Body<'tcx>> {
     let hir_id = tcx.hir().as_local_hir_id(def_id).unwrap();
     if let hir::BodyOwnerKind::Const = tcx.hir().body_owner_kind_by_hir_id(hir_id) {
         // Ensure that we compute the `mir_const_qualif` for constants at
@@ -227,8 +227,8 @@ fn mir_validated<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>, def_id: DefId) -> &'tcx
     tcx.alloc_steal_mir(mir)
 }
 
-fn optimized_mir<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>, def_id: DefId) -> &'tcx Mir<'tcx> {
-    // (Mir-)Borrowck uses `mir_validated`, so we have to force it to
+fn optimized_mir<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>, def_id: DefId) -> &'tcx Body<'tcx> {
+    // `mir_borrowck` uses `mir_validated`, so we have to force it to
     // execute before we can steal.
     tcx.ensure().mir_borrowck(def_id);
 
diff --git a/src/librustc_mir/transform/no_landing_pads.rs b/src/librustc_mir/transform/no_landing_pads.rs
index 648f4e65b0d..719e22ca150 100644
--- a/src/librustc_mir/transform/no_landing_pads.rs
+++ b/src/librustc_mir/transform/no_landing_pads.rs
@@ -12,14 +12,14 @@ impl MirPass for NoLandingPads {
     fn run_pass<'a, 'tcx>(&self,
                           tcx: TyCtxt<'a, 'tcx, 'tcx>,
                           _: MirSource<'tcx>,
-                          mir: &mut Mir<'tcx>) {
+                          mir: &mut Body<'tcx>) {
         no_landing_pads(tcx, mir)
     }
 }
 
-pub fn no_landing_pads<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>, mir: &mut Mir<'tcx>) {
+pub fn no_landing_pads<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>, mir: &mut Body<'tcx>) {
     if tcx.sess.no_landing_pads() {
-        NoLandingPads.visit_mir(mir);
+        NoLandingPads.visit_body(mir);
     }
 }
 
diff --git a/src/librustc_mir/transform/promote_consts.rs b/src/librustc_mir/transform/promote_consts.rs
index 0bf96c68917..4b95fbf4b7d 100644
--- a/src/librustc_mir/transform/promote_consts.rs
+++ b/src/librustc_mir/transform/promote_consts.rs
@@ -71,7 +71,7 @@ pub enum Candidate {
 struct TempCollector<'tcx> {
     temps: IndexVec<Local, TempState>,
     span: Span,
-    mir: &'tcx Mir<'tcx>,
+    mir: &'tcx Body<'tcx>,
 }
 
 impl<'tcx> Visitor<'tcx> for TempCollector<'tcx> {
@@ -134,7 +134,7 @@ impl<'tcx> Visitor<'tcx> for TempCollector<'tcx> {
     }
 }
 
-pub fn collect_temps(mir: &Mir<'_>,
+pub fn collect_temps(mir: &Body<'_>,
                      rpo: &mut ReversePostorder<'_, '_>) -> IndexVec<Local, TempState> {
     let mut collector = TempCollector {
         temps: IndexVec::from_elem(TempState::Undefined, &mir.local_decls),
@@ -149,8 +149,8 @@ pub fn collect_temps(mir: &Mir<'_>,
 
 struct Promoter<'a, 'tcx: 'a> {
     tcx: TyCtxt<'a, 'tcx, 'tcx>,
-    source: &'a mut Mir<'tcx>,
-    promoted: Mir<'tcx>,
+    source: &'a mut Body<'tcx>,
+    promoted: Body<'tcx>,
     temps: &'a mut IndexVec<Local, TempState>,
 
     /// If true, all nested temps are also kept in the
@@ -369,7 +369,7 @@ impl<'a, 'tcx> MutVisitor<'tcx> for Promoter<'a, 'tcx> {
     }
 }
 
-pub fn promote_candidates<'a, 'tcx>(mir: &mut Mir<'tcx>,
+pub fn promote_candidates<'a, 'tcx>(mir: &mut Body<'tcx>,
                                     tcx: TyCtxt<'a, 'tcx, 'tcx>,
                                     mut temps: IndexVec<Local, TempState>,
                                     candidates: Vec<Candidate>) {
@@ -393,13 +393,13 @@ pub fn promote_candidates<'a, 'tcx>(mir: &mut Mir<'tcx>,
         }
 
 
-        // Declare return place local so that `Mir::new` doesn't complain.
+        // Declare return place local so that `mir::Body::new` doesn't complain.
         let initial_locals = iter::once(
             LocalDecl::new_return_place(tcx.types.never, mir.span)
         ).collect();
 
         let promoter = Promoter {
-            promoted: Mir::new(
+            promoted: Body::new(
                 IndexVec::new(),
                 // FIXME: maybe try to filter this to avoid blowing up
                 // memory usage?
diff --git a/src/librustc_mir/transform/qualify_consts.rs b/src/librustc_mir/transform/qualify_consts.rs
index dca28368393..a416792101f 100644
--- a/src/librustc_mir/transform/qualify_consts.rs
+++ b/src/librustc_mir/transform/qualify_consts.rs
@@ -113,7 +113,7 @@ struct ConstCx<'a, 'tcx> {
     tcx: TyCtxt<'a, 'tcx, 'tcx>,
     param_env: ty::ParamEnv<'tcx>,
     mode: Mode,
-    mir: &'a Mir<'tcx>,
+    mir: &'a Body<'tcx>,
 
     per_local: PerQualif<BitSet<Local>>,
 }
@@ -619,7 +619,7 @@ impl Deref for Checker<'a, 'tcx> {
 impl<'a, 'tcx> Checker<'a, 'tcx> {
     fn new(tcx: TyCtxt<'a, 'tcx, 'tcx>,
            def_id: DefId,
-           mir: &'a Mir<'tcx>,
+           mir: &'a Body<'tcx>,
            mode: Mode)
            -> Self {
         assert!(def_id.is_local());
@@ -1431,7 +1431,7 @@ fn mir_const_qualif<'a, 'tcx>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
     let mir = &tcx.mir_const(def_id).borrow();
 
     if mir.return_ty().references_error() {
-        tcx.sess.delay_span_bug(mir.span, "mir_const_qualif: Mir had errors");
+        tcx.sess.delay_span_bug(mir.span, "mir_const_qualif: MIR had errors");
         return (1 << IsNotPromotable::IDX, tcx.arena.alloc(BitSet::new_empty(0)));
     }
 
@@ -1444,10 +1444,10 @@ impl MirPass for QualifyAndPromoteConstants {
     fn run_pass<'a, 'tcx>(&self,
                           tcx: TyCtxt<'a, 'tcx, 'tcx>,
                           src: MirSource<'tcx>,
-                          mir: &mut Mir<'tcx>) {
+                          mir: &mut Body<'tcx>) {
         // There's not really any point in promoting errorful MIR.
         if mir.return_ty().references_error() {
-            tcx.sess.delay_span_bug(mir.span, "QualifyAndPromoteConstants: Mir had errors");
+            tcx.sess.delay_span_bug(mir.span, "QualifyAndPromoteConstants: MIR had errors");
             return;
         }
 
diff --git a/src/librustc_mir/transform/qualify_min_const_fn.rs b/src/librustc_mir/transform/qualify_min_const_fn.rs
index a1e2d0683d3..4811380e238 100644
--- a/src/librustc_mir/transform/qualify_min_const_fn.rs
+++ b/src/librustc_mir/transform/qualify_min_const_fn.rs
@@ -11,7 +11,7 @@ type McfResult = Result<(), (Span, Cow<'static, str>)>;
 pub fn is_min_const_fn(
     tcx: TyCtxt<'a, 'tcx, 'tcx>,
     def_id: DefId,
-    mir: &'a Mir<'tcx>,
+    mir: &'a Body<'tcx>,
 ) -> McfResult {
     let mut current = def_id;
     loop {
@@ -130,7 +130,7 @@ fn check_ty(
 
 fn check_rvalue(
     tcx: TyCtxt<'a, 'tcx, 'tcx>,
-    mir: &'a Mir<'tcx>,
+    mir: &'a Body<'tcx>,
     rvalue: &Rvalue<'tcx>,
     span: Span,
 ) -> McfResult {
@@ -210,7 +210,7 @@ fn check_rvalue(
 
 fn check_statement(
     tcx: TyCtxt<'a, 'tcx, 'tcx>,
-    mir: &'a Mir<'tcx>,
+    mir: &'a Body<'tcx>,
     statement: &Statement<'tcx>,
 ) -> McfResult {
     let span = statement.source_info.span;
@@ -250,7 +250,10 @@ fn check_operand(
     }
 }
 
-fn check_place(place: &Place<'tcx>, span: Span) -> McfResult {
+fn check_place(
+    place: &Place<'tcx>,
+    span: Span,
+) -> McfResult {
     place.iterate(|place_base, place_projection| {
         for proj in place_projection {
             match proj.elem {
@@ -277,7 +280,7 @@ fn check_place(place: &Place<'tcx>, span: Span) -> McfResult {
 
 fn check_terminator(
     tcx: TyCtxt<'a, 'tcx, 'tcx>,
-    mir: &'a Mir<'tcx>,
+    mir: &'a Body<'tcx>,
     terminator: &Terminator<'tcx>,
 ) -> McfResult {
     let span = terminator.source_info.span;
diff --git a/src/librustc_mir/transform/remove_noop_landing_pads.rs b/src/librustc_mir/transform/remove_noop_landing_pads.rs
index b7493b25d46..42818a57115 100644
--- a/src/librustc_mir/transform/remove_noop_landing_pads.rs
+++ b/src/librustc_mir/transform/remove_noop_landing_pads.rs
@@ -11,7 +11,7 @@ pub struct RemoveNoopLandingPads;
 
 pub fn remove_noop_landing_pads<'a, 'tcx>(
     tcx: TyCtxt<'a, 'tcx, 'tcx>,
-    mir: &mut Mir<'tcx>)
+    mir: &mut Body<'tcx>)
 {
     if tcx.sess.no_landing_pads() {
         return
@@ -25,7 +25,7 @@ impl MirPass for RemoveNoopLandingPads {
     fn run_pass<'a, 'tcx>(&self,
                           tcx: TyCtxt<'a, 'tcx, 'tcx>,
                           _src: MirSource<'tcx>,
-                          mir: &mut Mir<'tcx>) {
+                          mir: &mut Body<'tcx>) {
         remove_noop_landing_pads(tcx, mir);
     }
 }
@@ -34,7 +34,7 @@ impl RemoveNoopLandingPads {
     fn is_nop_landing_pad(
         &self,
         bb: BasicBlock,
-        mir: &Mir<'_>,
+        mir: &Body<'_>,
         nop_landing_pads: &BitSet<BasicBlock>,
     ) -> bool {
         for stmt in &mir[bb].statements {
@@ -86,7 +86,7 @@ impl RemoveNoopLandingPads {
         }
     }
 
-    fn remove_nop_landing_pads(&self, mir: &mut Mir<'_>) {
+    fn remove_nop_landing_pads(&self, mir: &mut Body<'_>) {
         // make sure there's a single resume block
         let resume_block = {
             let patch = MirPatch::new(mir);
diff --git a/src/librustc_mir/transform/rustc_peek.rs b/src/librustc_mir/transform/rustc_peek.rs
index 7d2dbff996d..2b3eb9e1edf 100644
--- a/src/librustc_mir/transform/rustc_peek.rs
+++ b/src/librustc_mir/transform/rustc_peek.rs
@@ -5,7 +5,7 @@ use syntax_pos::Span;
 
 use rustc::ty::{self, TyCtxt};
 use rustc::hir::def_id::DefId;
-use rustc::mir::{self, Mir, Location};
+use rustc::mir::{self, Body, Location};
 use rustc_data_structures::bit_set::BitSet;
 use crate::transform::{MirPass, MirSource};
 
@@ -26,7 +26,7 @@ pub struct SanityCheck;
 
 impl MirPass for SanityCheck {
     fn run_pass<'a, 'tcx>(&self, tcx: TyCtxt<'a, 'tcx, 'tcx>,
-                          src: MirSource<'tcx>, mir: &mut Mir<'tcx>) {
+                          src: MirSource<'tcx>, mir: &mut Body<'tcx>) {
         let def_id = src.def_id();
         if !tcx.has_attr(def_id, sym::rustc_mir) {
             debug!("skipping rustc_peek::SanityCheck on {}", tcx.def_path_str(def_id));
@@ -85,7 +85,7 @@ impl MirPass for SanityCheck {
 /// expression form above, then that emits an error as well, but those
 /// errors are not intended to be used for unit tests.)
 pub fn sanity_check_via_rustc_peek<'a, 'tcx, O>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
-                                                mir: &Mir<'tcx>,
+                                                mir: &Body<'tcx>,
                                                 def_id: DefId,
                                                 _attributes: &[ast::Attribute],
                                                 results: &DataflowResults<'tcx, O>)
@@ -102,7 +102,7 @@ pub fn sanity_check_via_rustc_peek<'a, 'tcx, O>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
 }
 
 fn each_block<'a, 'tcx, O>(tcx: TyCtxt<'a, 'tcx, 'tcx>,
-                           mir: &Mir<'tcx>,
+                           mir: &Body<'tcx>,
                            results: &DataflowResults<'tcx, O>,
                            bb: mir::BasicBlock) where
     O: BitDenotation<'tcx, Idx=MovePathIndex> + HasMoveData<'tcx>
diff --git a/src/librustc_mir/transform/simplify.rs b/src/librustc_mir/transform/simplify.rs
index ee16ec7b41c..e7be238e850 100644
--- a/src/librustc_mir/transform/simplify.rs
+++ b/src/librustc_mir/transform/simplify.rs
@@ -44,7 +44,7 @@ impl SimplifyCfg {
     }
 }
 
-pub fn simplify_cfg(mir: &mut Mir<'_>) {
+pub fn simplify_cfg(mir: &mut Body<'_>) {
     CfgSimplifier::new(mir).simplify();
     remove_dead_blocks(mir);
 
@@ -60,7 +60,7 @@ impl MirPass for SimplifyCfg {
     fn run_pass<'a, 'tcx>(&self,
                           _tcx: TyCtxt<'a, 'tcx, 'tcx>,
                           _src: MirSource<'tcx>,
-                          mir: &mut Mir<'tcx>) {
+                          mir: &mut Body<'tcx>) {
         debug!("SimplifyCfg({:?}) - simplifying {:?}", self.label, mir);
         simplify_cfg(mir);
     }
@@ -72,7 +72,7 @@ pub struct CfgSimplifier<'a, 'tcx: 'a> {
 }
 
 impl<'a, 'tcx: 'a> CfgSimplifier<'a, 'tcx> {
-    pub fn new(mir: &'a mut Mir<'tcx>) -> Self {
+    pub fn new(mir: &'a mut Body<'tcx>) -> Self {
         let mut pred_count = IndexVec::from_elem(0u32, mir.basic_blocks());
 
         // we can't use mir.predecessors() here because that counts
@@ -263,7 +263,7 @@ impl<'a, 'tcx: 'a> CfgSimplifier<'a, 'tcx> {
     }
 }
 
-pub fn remove_dead_blocks(mir: &mut Mir<'_>) {
+pub fn remove_dead_blocks(mir: &mut Body<'_>) {
     let mut seen = BitSet::new_empty(mir.basic_blocks().len());
     for (bb, _) in traversal::preorder(mir) {
         seen.insert(bb.index());
@@ -299,9 +299,9 @@ impl MirPass for SimplifyLocals {
     fn run_pass<'a, 'tcx>(&self,
                           tcx: TyCtxt<'a, 'tcx, 'tcx>,
                           _: MirSource<'tcx>,
-                          mir: &mut Mir<'tcx>) {
+                          mir: &mut Body<'tcx>) {
         let mut marker = DeclMarker { locals: BitSet::new_empty(mir.local_decls.len()) };
-        marker.visit_mir(mir);
+        marker.visit_body(mir);
         // Return pointer and arguments are always live
         marker.locals.insert(RETURN_PLACE);
         for arg in mir.args_iter() {
@@ -317,7 +317,7 @@ impl MirPass for SimplifyLocals {
 
         let map = make_local_map(&mut mir.local_decls, marker.locals);
         // Update references to all vars and tmps now
-        LocalUpdater { map }.visit_mir(mir);
+        LocalUpdater { map }.visit_body(mir);
         mir.local_decls.shrink_to_fit();
     }
 }
diff --git a/src/librustc_mir/transform/simplify_branches.rs b/src/librustc_mir/transform/simplify_branches.rs
index db73e829c53..53949bcfcd7 100644
--- a/src/librustc_mir/transform/simplify_branches.rs
+++ b/src/librustc_mir/transform/simplify_branches.rs
@@ -22,7 +22,7 @@ impl MirPass for SimplifyBranches {
     fn run_pass<'a, 'tcx>(&self,
                           tcx: TyCtxt<'a, 'tcx, 'tcx>,
                           _src: MirSource<'tcx>,
-                          mir: &mut Mir<'tcx>) {
+                          mir: &mut Body<'tcx>) {
         for block in mir.basic_blocks_mut() {
             let terminator = block.terminator_mut();
             terminator.kind = match terminator.kind {
diff --git a/src/librustc_mir/transform/uniform_array_move_out.rs b/src/librustc_mir/transform/uniform_array_move_out.rs
index a2433ab838d..ee1d2ca2a89 100644
--- a/src/librustc_mir/transform/uniform_array_move_out.rs
+++ b/src/librustc_mir/transform/uniform_array_move_out.rs
@@ -40,18 +40,18 @@ impl MirPass for UniformArrayMoveOut {
     fn run_pass<'a, 'tcx>(&self,
                           tcx: TyCtxt<'a, 'tcx, 'tcx>,
                           _src: MirSource<'tcx>,
-                          mir: &mut Mir<'tcx>) {
+                          mir: &mut Body<'tcx>) {
         let mut patch = MirPatch::new(mir);
         {
             let mut visitor = UniformArrayMoveOutVisitor{mir, patch: &mut patch, tcx};
-            visitor.visit_mir(mir);
+            visitor.visit_body(mir);
         }
         patch.apply(mir);
     }
 }
 
 struct UniformArrayMoveOutVisitor<'a, 'tcx: 'a> {
-    mir: &'a Mir<'tcx>,
+    mir: &'a Body<'tcx>,
     patch: &'a mut MirPatch<'tcx>,
     tcx: TyCtxt<'a, 'tcx, 'tcx>,
 }
@@ -165,14 +165,14 @@ impl MirPass for RestoreSubsliceArrayMoveOut {
     fn run_pass<'a, 'tcx>(&self,
                           tcx: TyCtxt<'a, 'tcx, 'tcx>,
                           _src: MirSource<'tcx>,
-                          mir: &mut Mir<'tcx>) {
+                          mir: &mut Body<'tcx>) {
         let mut patch = MirPatch::new(mir);
         {
             let mut visitor = RestoreDataCollector {
                 locals_use: IndexVec::from_elem(LocalUse::new(), &mir.local_decls),
                 candidates: vec![],
             };
-            visitor.visit_mir(mir);
+            visitor.visit_body(mir);
 
             for candidate in &visitor.candidates {
                 let statement = &mir[candidate.block].statements[candidate.statement_index];
@@ -254,7 +254,7 @@ impl RestoreSubsliceArrayMoveOut {
     }
 
     fn try_get_item_source<'a, 'tcx>(local_use: &LocalUse,
-                                     mir: &'a Mir<'tcx>) -> Option<(u32, &'a Place<'tcx>)> {
+                                     mir: &'a Body<'tcx>) -> Option<(u32, &'a Place<'tcx>)> {
         if let Some(location) = local_use.first_use {
             let block = &mir[location.block];
             if block.statements.len() > location.statement_index {
diff --git a/src/librustc_mir/util/collect_writes.rs b/src/librustc_mir/util/collect_writes.rs
index 7bd61c3a59c..c8804dfbaf2 100644
--- a/src/librustc_mir/util/collect_writes.rs
+++ b/src/librustc_mir/util/collect_writes.rs
@@ -1,5 +1,5 @@
 use rustc::mir::{Local, Location};
-use rustc::mir::Mir;
+use rustc::mir::Body;
 use rustc::mir::visit::PlaceContext;
 use rustc::mir::visit::Visitor;
 
@@ -9,10 +9,10 @@ crate trait FindAssignments {
     fn find_assignments(&self, local: Local) -> Vec<Location>;
 }
 
-impl<'tcx> FindAssignments for Mir<'tcx>{
+impl<'tcx> FindAssignments for Body<'tcx>{
     fn find_assignments(&self, local: Local) -> Vec<Location>{
             let mut visitor = FindLocalAssignmentVisitor{ needle: local, locations: vec![]};
-            visitor.visit_mir(self);
+            visitor.visit_body(self);
             visitor.locations
     }
 }
diff --git a/src/librustc_mir/util/def_use.rs b/src/librustc_mir/util/def_use.rs
index 2925005b667..ba0190756c5 100644
--- a/src/librustc_mir/util/def_use.rs
+++ b/src/librustc_mir/util/def_use.rs
@@ -1,6 +1,6 @@
 //! Def-use analysis.
 
-use rustc::mir::{Local, Location, Mir};
+use rustc::mir::{Local, Location, Body};
 use rustc::mir::visit::{PlaceContext, MutVisitor, Visitor};
 use rustc_data_structures::indexed_vec::IndexVec;
 use std::mem;
@@ -21,19 +21,19 @@ pub struct Use {
 }
 
 impl DefUseAnalysis {
-    pub fn new(mir: &Mir<'_>) -> DefUseAnalysis {
+    pub fn new(mir: &Body<'_>) -> DefUseAnalysis {
         DefUseAnalysis {
             info: IndexVec::from_elem_n(Info::new(), mir.local_decls.len()),
         }
     }
 
-    pub fn analyze(&mut self, mir: &Mir<'_>) {
+    pub fn analyze(&mut self, mir: &Body<'_>) {
         self.clear();
 
         let mut finder = DefUseFinder {
             info: mem::replace(&mut self.info, IndexVec::new()),
         };
-        finder.visit_mir(mir);
+        finder.visit_body(mir);
         self.info = finder.info
     }
 
@@ -47,7 +47,7 @@ impl DefUseAnalysis {
         &self.info[local]
     }
 
-    fn mutate_defs_and_uses<F>(&self, local: Local, mir: &mut Mir<'_>, mut callback: F)
+    fn mutate_defs_and_uses<F>(&self, local: Local, mir: &mut Body<'_>, mut callback: F)
                                where F: for<'a> FnMut(&'a mut Local,
                                                       PlaceContext,
                                                       Location) {
@@ -61,7 +61,7 @@ impl DefUseAnalysis {
     // FIXME(pcwalton): this should update the def-use chains.
     pub fn replace_all_defs_and_uses_with(&self,
                                           local: Local,
-                                          mir: &mut Mir<'_>,
+                                          mir: &mut Body<'_>,
                                           new_local: Local) {
         self.mutate_defs_and_uses(local, mir, |local, _, _| *local = new_local)
     }
@@ -123,7 +123,7 @@ struct MutateUseVisitor<F> {
 }
 
 impl<F> MutateUseVisitor<F> {
-    fn new(query: Local, callback: F, _: &Mir<'_>)
+    fn new(query: Local, callback: F, _: &Body<'_>)
            -> MutateUseVisitor<F>
            where F: for<'a> FnMut(&'a mut Local, PlaceContext, Location) {
         MutateUseVisitor {
diff --git a/src/librustc_mir/util/elaborate_drops.rs b/src/librustc_mir/util/elaborate_drops.rs
index ac5ebc5e251..076ba60c644 100644
--- a/src/librustc_mir/util/elaborate_drops.rs
+++ b/src/librustc_mir/util/elaborate_drops.rs
@@ -74,7 +74,7 @@ pub trait DropElaborator<'a, 'tcx: 'a> : fmt::Debug {
     type Path : Copy + fmt::Debug;
 
     fn patch(&mut self) -> &mut MirPatch<'tcx>;
-    fn mir(&self) -> &'a Mir<'tcx>;
+    fn mir(&self) -> &'a Body<'tcx>;
     fn tcx(&self) -> TyCtxt<'a, 'tcx, 'tcx>;
     fn param_env(&self) -> ty::ParamEnv<'tcx>;
 
diff --git a/src/librustc_mir/util/graphviz.rs b/src/librustc_mir/util/graphviz.rs
index fc4c6b3fd3f..20d92da9ba3 100644
--- a/src/librustc_mir/util/graphviz.rs
+++ b/src/librustc_mir/util/graphviz.rs
@@ -34,7 +34,7 @@ pub fn graphviz_safe_def_name(def_id: DefId) -> String {
 /// Write a graphviz DOT graph of the MIR.
 pub fn write_mir_fn_graphviz<'tcx, W>(tcx: TyCtxt<'_, '_, 'tcx>,
                                       def_id: DefId,
-                                      mir: &Mir<'_>,
+                                      mir: &Body<'_>,
                                       w: &mut W) -> io::Result<()>
     where W: Write
 {
@@ -68,7 +68,7 @@ pub fn write_mir_fn_graphviz<'tcx, W>(tcx: TyCtxt<'_, '_, 'tcx>,
 /// `init` and `fini` are callbacks for emitting additional rows of
 /// data (using HTML enclosed with `<tr>` in the emitted text).
 pub fn write_node_label<W: Write, INIT, FINI>(block: BasicBlock,
-                                              mir: &Mir<'_>,
+                                              mir: &Body<'_>,
                                               w: &mut W,
                                               num_cols: u32,
                                               init: INIT,
@@ -110,7 +110,7 @@ pub fn write_node_label<W: Write, INIT, FINI>(block: BasicBlock,
 }
 
 /// Write a graphviz DOT node for the given basic block.
-fn write_node<W: Write>(block: BasicBlock, mir: &Mir<'_>, w: &mut W) -> io::Result<()> {
+fn write_node<W: Write>(block: BasicBlock, mir: &Body<'_>, w: &mut W) -> io::Result<()> {
     // Start a new node with the label to follow, in one of DOT's pseudo-HTML tables.
     write!(w, r#"    {} [shape="none", label=<"#, node(block))?;
     write_node_label(block, mir, w, 1, |_| Ok(()), |_| Ok(()))?;
@@ -119,7 +119,7 @@ fn write_node<W: Write>(block: BasicBlock, mir: &Mir<'_>, w: &mut W) -> io::Resu
 }
 
 /// Write graphviz DOT edges with labels between the given basic block and all of its successors.
-fn write_edges<W: Write>(source: BasicBlock, mir: &Mir<'_>, w: &mut W) -> io::Result<()> {
+fn write_edges<W: Write>(source: BasicBlock, mir: &Body<'_>, w: &mut W) -> io::Result<()> {
     let terminator = mir[source].terminator();
     let labels = terminator.kind.fmt_successor_labels();
 
@@ -135,7 +135,7 @@ fn write_edges<W: Write>(source: BasicBlock, mir: &Mir<'_>, w: &mut W) -> io::Re
 /// all the variables and temporaries.
 fn write_graph_label<'a, 'gcx, 'tcx, W: Write>(tcx: TyCtxt<'a, 'gcx, 'tcx>,
                                                def_id: DefId,
-                                               mir: &Mir<'_>,
+                                               mir: &Body<'_>,
                                                w: &mut W)
                                                -> io::Result<()> {
     write!(w, "    label=<fn {}(", dot::escape_html(&tcx.def_path_str(def_id)))?;
diff --git a/src/librustc_mir/util/liveness.rs b/src/librustc_mir/util/liveness.rs
index 8d9a878fc9e..a3317d3956b 100644
--- a/src/librustc_mir/util/liveness.rs
+++ b/src/librustc_mir/util/liveness.rs
@@ -57,7 +57,7 @@ pub struct LivenessResult {
 /// Computes which local variables are live within the given function
 /// `mir`, including drops.
 pub fn liveness_of_locals<'tcx>(
-    mir: &Mir<'tcx>,
+    mir: &Body<'tcx>,
 ) -> LivenessResult {
     let num_live_vars = mir.local_decls.len();
 
@@ -258,7 +258,7 @@ pub fn dump_mir<'a, 'tcx>(
     tcx: TyCtxt<'a, 'tcx, 'tcx>,
     pass_name: &str,
     source: MirSource<'tcx>,
-    mir: &Mir<'tcx>,
+    mir: &Body<'tcx>,
     result: &LivenessResult,
 ) {
     if !dump_enabled(tcx, pass_name, source) {
@@ -276,7 +276,7 @@ fn dump_matched_mir_node<'a, 'tcx>(
     pass_name: &str,
     node_path: &str,
     source: MirSource<'tcx>,
-    mir: &Mir<'tcx>,
+    mir: &Body<'tcx>,
     result: &LivenessResult,
 ) {
     let mut file_path = PathBuf::new();
@@ -297,7 +297,7 @@ fn dump_matched_mir_node<'a, 'tcx>(
 pub fn write_mir_fn<'a, 'tcx>(
     tcx: TyCtxt<'a, 'tcx, 'tcx>,
     src: MirSource<'tcx>,
-    mir: &Mir<'tcx>,
+    mir: &Body<'tcx>,
     w: &mut dyn Write,
     result: &LivenessResult,
 ) -> io::Result<()> {
diff --git a/src/librustc_mir/util/patch.rs b/src/librustc_mir/util/patch.rs
index 366cd71f6d4..974dda867bc 100644
--- a/src/librustc_mir/util/patch.rs
+++ b/src/librustc_mir/util/patch.rs
@@ -17,7 +17,7 @@ pub struct MirPatch<'tcx> {
 }
 
 impl<'tcx> MirPatch<'tcx> {
-    pub fn new(mir: &Mir<'tcx>) -> Self {
+    pub fn new(mir: &Body<'tcx>) -> Self {
         let mut result = MirPatch {
             patch_map: IndexVec::from_elem(None, mir.basic_blocks()),
             new_blocks: vec![],
@@ -75,7 +75,7 @@ impl<'tcx> MirPatch<'tcx> {
         self.patch_map[bb].is_some()
     }
 
-    pub fn terminator_loc(&self, mir: &Mir<'tcx>, bb: BasicBlock) -> Location {
+    pub fn terminator_loc(&self, mir: &Body<'tcx>, bb: BasicBlock) -> Location {
         let offset = match bb.index().checked_sub(mir.basic_blocks().len()) {
             Some(index) => self.new_blocks[index].statements.len(),
             None => mir[bb].statements.len()
@@ -127,7 +127,7 @@ impl<'tcx> MirPatch<'tcx> {
         self.make_nop.push(loc);
     }
 
-    pub fn apply(self, mir: &mut Mir<'tcx>) {
+    pub fn apply(self, mir: &mut Body<'tcx>) {
         debug!("MirPatch: make nops at: {:?}", self.make_nop);
         for loc in self.make_nop {
             mir.make_statement_nop(loc);
@@ -177,7 +177,7 @@ impl<'tcx> MirPatch<'tcx> {
         }
     }
 
-    pub fn source_info_for_location(&self, mir: &Mir<'_>, loc: Location) -> SourceInfo {
+    pub fn source_info_for_location(&self, mir: &Body<'_>, loc: Location) -> SourceInfo {
         let data = match loc.block.index().checked_sub(mir.basic_blocks().len()) {
             Some(new) => &self.new_blocks[new],
             None => &mir[loc.block]
diff --git a/src/librustc_mir/util/pretty.rs b/src/librustc_mir/util/pretty.rs
index cf90f44e670..aec8ce7ced6 100644
--- a/src/librustc_mir/util/pretty.rs
+++ b/src/librustc_mir/util/pretty.rs
@@ -68,7 +68,7 @@ pub fn dump_mir<'a, 'gcx, 'tcx, F>(
     pass_name: &str,
     disambiguator: &dyn Display,
     source: MirSource<'tcx>,
-    mir: &Mir<'tcx>,
+    mir: &Body<'tcx>,
     extra_data: F,
 ) where
     F: FnMut(PassWhere, &mut dyn Write) -> io::Result<()>,
@@ -124,7 +124,7 @@ fn dump_matched_mir_node<'a, 'gcx, 'tcx, F>(
     node_path: &str,
     disambiguator: &dyn Display,
     source: MirSource<'tcx>,
-    mir: &Mir<'tcx>,
+    mir: &Body<'tcx>,
     mut extra_data: F,
 ) where
     F: FnMut(PassWhere, &mut dyn Write) -> io::Result<()>,
@@ -282,7 +282,7 @@ pub fn write_mir_pretty<'a, 'gcx, 'tcx>(
 pub fn write_mir_fn<'a, 'gcx, 'tcx, F>(
     tcx: TyCtxt<'a, 'gcx, 'tcx>,
     src: MirSource<'tcx>,
-    mir: &Mir<'tcx>,
+    mir: &Body<'tcx>,
     extra_data: &mut F,
     w: &mut dyn Write,
 ) -> io::Result<()>
@@ -306,7 +306,7 @@ where
 pub fn write_basic_block<'cx, 'gcx, 'tcx, F>(
     tcx: TyCtxt<'cx, 'gcx, 'tcx>,
     block: BasicBlock,
-    mir: &Mir<'tcx>,
+    mir: &Body<'tcx>,
     extra_data: &mut F,
     w: &mut dyn Write,
 ) -> io::Result<()>
@@ -464,7 +464,7 @@ fn comment(tcx: TyCtxt<'_, '_, '_>, SourceInfo { span, scope }: SourceInfo) -> S
 /// Prints local variables in a scope tree.
 fn write_scope_tree(
     tcx: TyCtxt<'_, '_, '_>,
-    mir: &Mir<'_>,
+    mir: &Body<'_>,
     scope_tree: &FxHashMap<SourceScope, Vec<SourceScope>>,
     w: &mut dyn Write,
     parent: SourceScope,
@@ -541,7 +541,7 @@ fn write_scope_tree(
 pub fn write_mir_intro<'a, 'gcx, 'tcx>(
     tcx: TyCtxt<'a, 'gcx, 'tcx>,
     src: MirSource<'tcx>,
-    mir: &Mir<'_>,
+    mir: &Body<'_>,
     w: &mut dyn Write,
 ) -> io::Result<()> {
     write_mir_sig(tcx, src, mir, w)?;
@@ -572,7 +572,7 @@ pub fn write_mir_intro<'a, 'gcx, 'tcx>(
 fn write_mir_sig(
     tcx: TyCtxt<'_, '_, '_>,
     src: MirSource<'tcx>,
-    mir: &Mir<'_>,
+    mir: &Body<'_>,
     w: &mut dyn Write,
 ) -> io::Result<()> {
     use rustc::hir::def::DefKind;
@@ -629,7 +629,7 @@ fn write_mir_sig(
     Ok(())
 }
 
-fn write_user_type_annotations(mir: &Mir<'_>, w: &mut dyn Write) -> io::Result<()> {
+fn write_user_type_annotations(mir: &Body<'_>, w: &mut dyn Write) -> io::Result<()> {
     if !mir.user_type_annotations.is_empty() {
         writeln!(w, "| User Type Annotations")?;
     }
diff --git a/src/libsyntax/source_map.rs b/src/libsyntax/source_map.rs
index 8a210db9185..e2171a84e23 100644
--- a/src/libsyntax/source_map.rs
+++ b/src/libsyntax/source_map.rs
@@ -727,6 +727,11 @@ impl SourceMap {
         debug!("find_width_of_character_at_span: local_begin=`{:?}`, local_end=`{:?}`",
                local_begin, local_end);
 
+        if local_begin.sf.start_pos != local_end.sf.start_pos {
+            debug!("find_width_of_character_at_span: begin and end are in different files");
+            return 1;
+        }
+
         let start_index = local_begin.pos.to_usize();
         let end_index = local_end.pos.to_usize();
         debug!("find_width_of_character_at_span: start_index=`{:?}`, end_index=`{:?}`",
diff --git a/src/test/run-pass/regions/regions-lub-ref-ref-rc.rs b/src/test/run-pass/regions/regions-lub-ref-ref-rc.rs
index cd095f6f3a4..96c71b084b1 100644
--- a/src/test/run-pass/regions/regions-lub-ref-ref-rc.rs
+++ b/src/test/run-pass/regions/regions-lub-ref-ref-rc.rs
@@ -11,16 +11,16 @@
 use std::rc::Rc;
 
 #[derive(Clone)]
-enum CachedMir<'mir> {
+enum Cached<'mir> {
     Ref(&'mir String),
     Owned(Rc<String>),
 }
 
-impl<'mir> CachedMir<'mir> {
+impl<'mir> Cached<'mir> {
     fn get_ref<'a>(&'a self) -> &'a String {
         match *self {
-            CachedMir::Ref(r) => r,
-            CachedMir::Owned(ref rc) => &rc,
+            Cached::Ref(r) => r,
+            Cached::Owned(ref rc) => &rc,
         }
     }
 }