diff --git a/Cargo.lock b/Cargo.lock
index 6849c40a54f23..3875ea9921642 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -3598,6 +3598,33 @@ dependencies = [
  "rustc_span",
 ]
 
+[[package]]
+name = "rustc_borrowck"
+version = "0.0.0"
+dependencies = [
+ "either",
+ "itertools 0.9.0",
+ "polonius-engine",
+ "rustc_const_eval",
+ "rustc_data_structures",
+ "rustc_errors",
+ "rustc_graphviz",
+ "rustc_hir",
+ "rustc_index",
+ "rustc_infer",
+ "rustc_lexer",
+ "rustc_middle",
+ "rustc_mir_dataflow",
+ "rustc_serialize",
+ "rustc_session",
+ "rustc_span",
+ "rustc_target",
+ "rustc_trait_selection",
+ "rustc_traits",
+ "smallvec",
+ "tracing",
+]
+
 [[package]]
 name = "rustc_builtin_macros"
 version = "0.0.0"
@@ -3681,6 +3708,30 @@ dependencies = [
  "tracing",
 ]
 
+[[package]]
+name = "rustc_const_eval"
+version = "0.0.0"
+dependencies = [
+ "either",
+ "gsgdt",
+ "rustc_apfloat",
+ "rustc_ast",
+ "rustc_attr",
+ "rustc_data_structures",
+ "rustc_errors",
+ "rustc_hir",
+ "rustc_index",
+ "rustc_infer",
+ "rustc_macros",
+ "rustc_middle",
+ "rustc_mir_dataflow",
+ "rustc_session",
+ "rustc_span",
+ "rustc_target",
+ "rustc_trait_selection",
+ "tracing",
+]
+
 [[package]]
 name = "rustc_data_structures"
 version = "0.0.0"
@@ -3719,6 +3770,7 @@ dependencies = [
  "rustc_ast",
  "rustc_ast_pretty",
  "rustc_codegen_ssa",
+ "rustc_const_eval",
  "rustc_data_structures",
  "rustc_error_codes",
  "rustc_errors",
@@ -3729,7 +3781,6 @@ dependencies = [
  "rustc_lint",
  "rustc_metadata",
  "rustc_middle",
- "rustc_mir",
  "rustc_parse",
  "rustc_plugin_impl",
  "rustc_save_analysis",
@@ -3888,9 +3939,11 @@ dependencies = [
  "rustc_ast_lowering",
  "rustc_ast_passes",
  "rustc_attr",
+ "rustc_borrowck",
  "rustc_builtin_macros",
  "rustc_codegen_llvm",
  "rustc_codegen_ssa",
+ "rustc_const_eval",
  "rustc_data_structures",
  "rustc_errors",
  "rustc_expand",
@@ -3899,8 +3952,9 @@ dependencies = [
  "rustc_lint",
  "rustc_metadata",
  "rustc_middle",
- "rustc_mir",
  "rustc_mir_build",
+ "rustc_mir_transform",
+ "rustc_monomorphize",
  "rustc_parse",
  "rustc_passes",
  "rustc_plugin_impl",
@@ -4018,6 +4072,8 @@ version = "0.0.0"
 dependencies = [
  "bitflags",
  "chalk-ir",
+ "either",
+ "gsgdt",
  "polonius-engine",
  "rustc-rayon-core",
  "rustc_apfloat",
@@ -4027,6 +4083,7 @@ dependencies = [
  "rustc_data_structures",
  "rustc_errors",
  "rustc_feature",
+ "rustc_graphviz",
  "rustc_hir",
  "rustc_index",
  "rustc_macros",
@@ -4041,51 +4098,63 @@ dependencies = [
 ]
 
 [[package]]
-name = "rustc_mir"
+name = "rustc_mir_build"
 version = "0.0.0"
 dependencies = [
- "coverage_test_macros",
- "either",
- "gsgdt",
- "itertools 0.9.0",
- "polonius-engine",
- "regex",
  "rustc_apfloat",
+ "rustc_arena",
  "rustc_ast",
  "rustc_attr",
  "rustc_data_structures",
  "rustc_errors",
- "rustc_graphviz",
  "rustc_hir",
  "rustc_index",
  "rustc_infer",
- "rustc_lexer",
- "rustc_macros",
  "rustc_middle",
  "rustc_serialize",
  "rustc_session",
  "rustc_span",
  "rustc_target",
  "rustc_trait_selection",
- "rustc_traits",
  "smallvec",
  "tracing",
 ]
 
 [[package]]
-name = "rustc_mir_build"
+name = "rustc_mir_dataflow"
 version = "0.0.0"
 dependencies = [
- "rustc_apfloat",
- "rustc_arena",
+ "polonius-engine",
+ "regex",
+ "rustc_ast",
+ "rustc_data_structures",
+ "rustc_graphviz",
+ "rustc_hir",
+ "rustc_index",
+ "rustc_middle",
+ "rustc_serialize",
+ "rustc_session",
+ "rustc_span",
+ "rustc_target",
+ "smallvec",
+ "tracing",
+]
+
+[[package]]
+name = "rustc_mir_transform"
+version = "0.0.0"
+dependencies = [
+ "coverage_test_macros",
+ "itertools 0.9.0",
  "rustc_ast",
  "rustc_attr",
+ "rustc_const_eval",
  "rustc_data_structures",
  "rustc_errors",
  "rustc_hir",
  "rustc_index",
- "rustc_infer",
  "rustc_middle",
+ "rustc_mir_dataflow",
  "rustc_serialize",
  "rustc_session",
  "rustc_span",
@@ -4095,6 +4164,22 @@ dependencies = [
  "tracing",
 ]
 
+[[package]]
+name = "rustc_monomorphize"
+version = "0.0.0"
+dependencies = [
+ "rustc_data_structures",
+ "rustc_errors",
+ "rustc_hir",
+ "rustc_index",
+ "rustc_middle",
+ "rustc_session",
+ "rustc_span",
+ "rustc_target",
+ "smallvec",
+ "tracing",
+]
+
 [[package]]
 name = "rustc_parse"
 version = "0.0.0"
diff --git a/compiler/rustc_mir/Cargo.toml b/compiler/rustc_borrowck/Cargo.toml
similarity index 74%
rename from compiler/rustc_mir/Cargo.toml
rename to compiler/rustc_borrowck/Cargo.toml
index 3049fb3b383b3..c683c388ba9ea 100644
--- a/compiler/rustc_mir/Cargo.toml
+++ b/compiler/rustc_borrowck/Cargo.toml
@@ -1,5 +1,5 @@
 [package]
-name = "rustc_mir"
+name = "rustc_borrowck"
 version = "0.0.0"
 edition = "2018"
 
@@ -8,30 +8,23 @@ doctest = false
 
 [dependencies]
 either = "1.5.0"
-rustc_graphviz = { path = "../rustc_graphviz" }
-gsgdt = "0.1.2"
 itertools = "0.9"
 tracing = "0.1"
 polonius-engine = "0.13.0"
-regex = "1"
-rustc_middle = { path = "../rustc_middle" }
-rustc_attr = { path = "../rustc_attr" }
+smallvec = { version = "1.6.1", features = ["union", "may_dangle"] }
 rustc_data_structures = { path = "../rustc_data_structures" }
 rustc_errors = { path = "../rustc_errors" }
+rustc_graphviz = { path = "../rustc_graphviz" }
 rustc_hir = { path = "../rustc_hir" }
 rustc_index = { path = "../rustc_index" }
 rustc_infer = { path = "../rustc_infer" }
 rustc_lexer = { path = "../rustc_lexer" }
-rustc_macros = { path = "../rustc_macros" }
+rustc_middle = { path = "../rustc_middle" }
+rustc_const_eval = { path = "../rustc_const_eval" }
+rustc_mir_dataflow = { path = "../rustc_mir_dataflow" }
 rustc_serialize = { path = "../rustc_serialize" }
 rustc_session = { path = "../rustc_session" }
 rustc_target = { path = "../rustc_target" }
 rustc_trait_selection = { path = "../rustc_trait_selection" }
 rustc_traits = { path = "../rustc_traits" }
-rustc_ast = { path = "../rustc_ast" }
 rustc_span = { path = "../rustc_span" }
-rustc_apfloat = { path = "../rustc_apfloat" }
-smallvec = { version = "1.6.1", features = ["union", "may_dangle"] }
-
-[dev-dependencies]
-coverage_test_macros = { path = "src/transform/coverage/test_macros" }
diff --git a/compiler/rustc_mir/src/borrow_check/borrow_set.rs b/compiler/rustc_borrowck/src/borrow_set.rs
similarity index 98%
rename from compiler/rustc_mir/src/borrow_check/borrow_set.rs
rename to compiler/rustc_borrowck/src/borrow_set.rs
index 288eda32e414e..ee2ce1d3f74c3 100644
--- a/compiler/rustc_mir/src/borrow_check/borrow_set.rs
+++ b/compiler/rustc_borrowck/src/borrow_set.rs
@@ -1,14 +1,14 @@
-use crate::borrow_check::nll::ToRegionVid;
-use crate::borrow_check::path_utils::allow_two_phase_borrow;
-use crate::borrow_check::place_ext::PlaceExt;
-use crate::dataflow::indexes::BorrowIndex;
-use crate::dataflow::move_paths::MoveData;
+use crate::nll::ToRegionVid;
+use crate::path_utils::allow_two_phase_borrow;
+use crate::place_ext::PlaceExt;
+use crate::BorrowIndex;
 use rustc_data_structures::fx::{FxHashMap, FxHashSet, FxIndexMap};
 use rustc_index::bit_set::BitSet;
 use rustc_middle::mir::traversal;
 use rustc_middle::mir::visit::{MutatingUseContext, NonUseContext, PlaceContext, Visitor};
 use rustc_middle::mir::{self, Body, Local, Location};
 use rustc_middle::ty::{RegionVid, TyCtxt};
+use rustc_mir_dataflow::move_paths::MoveData;
 use std::fmt;
 use std::ops::Index;
 
diff --git a/compiler/rustc_mir/src/util/borrowck_errors.rs b/compiler/rustc_borrowck/src/borrowck_errors.rs
similarity index 99%
rename from compiler/rustc_mir/src/util/borrowck_errors.rs
rename to compiler/rustc_borrowck/src/borrowck_errors.rs
index 56d8045813c42..5702203d7c4ff 100644
--- a/compiler/rustc_mir/src/util/borrowck_errors.rs
+++ b/compiler/rustc_borrowck/src/borrowck_errors.rs
@@ -2,7 +2,7 @@ use rustc_errors::{struct_span_err, DiagnosticBuilder, DiagnosticId};
 use rustc_middle::ty::{self, Ty, TyCtxt};
 use rustc_span::{MultiSpan, Span};
 
-impl<'cx, 'tcx> crate::borrow_check::MirBorrowckCtxt<'cx, 'tcx> {
+impl<'cx, 'tcx> crate::MirBorrowckCtxt<'cx, 'tcx> {
     crate fn cannot_move_when_borrowed(&self, span: Span, desc: &str) -> DiagnosticBuilder<'cx> {
         struct_span_err!(self, span, E0505, "cannot move out of {} because it is borrowed", desc,)
     }
diff --git a/compiler/rustc_mir/src/borrow_check/constraint_generation.rs b/compiler/rustc_borrowck/src/constraint_generation.rs
similarity index 99%
rename from compiler/rustc_mir/src/borrow_check/constraint_generation.rs
rename to compiler/rustc_borrowck/src/constraint_generation.rs
index c84928523d9d6..a40f148cdf88c 100644
--- a/compiler/rustc_mir/src/borrow_check/constraint_generation.rs
+++ b/compiler/rustc_borrowck/src/constraint_generation.rs
@@ -9,7 +9,7 @@ use rustc_middle::ty::fold::TypeFoldable;
 use rustc_middle::ty::subst::SubstsRef;
 use rustc_middle::ty::{self, RegionVid, Ty};
 
-use crate::borrow_check::{
+use crate::{
     borrow_set::BorrowSet, facts::AllFacts, location::LocationTable, nll::ToRegionVid,
     places_conflict, region_infer::values::LivenessValues,
 };
diff --git a/compiler/rustc_mir/src/borrow_check/constraints/graph.rs b/compiler/rustc_borrowck/src/constraints/graph.rs
similarity index 99%
rename from compiler/rustc_mir/src/borrow_check/constraints/graph.rs
rename to compiler/rustc_borrowck/src/constraints/graph.rs
index 9e4cfb2cc00fa..cb9e0234c49ff 100644
--- a/compiler/rustc_mir/src/borrow_check/constraints/graph.rs
+++ b/compiler/rustc_borrowck/src/constraints/graph.rs
@@ -4,7 +4,7 @@ use rustc_middle::mir::ConstraintCategory;
 use rustc_middle::ty::{RegionVid, VarianceDiagInfo};
 use rustc_span::DUMMY_SP;
 
-use crate::borrow_check::{
+use crate::{
     constraints::OutlivesConstraintIndex,
     constraints::{OutlivesConstraint, OutlivesConstraintSet},
     type_check::Locations,
diff --git a/compiler/rustc_mir/src/borrow_check/constraints/mod.rs b/compiler/rustc_borrowck/src/constraints/mod.rs
similarity index 98%
rename from compiler/rustc_mir/src/borrow_check/constraints/mod.rs
rename to compiler/rustc_borrowck/src/constraints/mod.rs
index b944479ca456b..98378a98684e2 100644
--- a/compiler/rustc_mir/src/borrow_check/constraints/mod.rs
+++ b/compiler/rustc_borrowck/src/constraints/mod.rs
@@ -5,7 +5,7 @@ use rustc_middle::ty::{RegionVid, VarianceDiagInfo};
 use std::fmt;
 use std::ops::Index;
 
-use crate::borrow_check::type_check::Locations;
+use crate::type_check::Locations;
 
 crate mod graph;
 
diff --git a/compiler/rustc_mir/src/borrow_check/consumers.rs b/compiler/rustc_borrowck/src/consumers.rs
similarity index 100%
rename from compiler/rustc_mir/src/borrow_check/consumers.rs
rename to compiler/rustc_borrowck/src/consumers.rs
diff --git a/compiler/rustc_mir/src/dataflow/impls/borrows.rs b/compiler/rustc_borrowck/src/dataflow.rs
similarity index 78%
rename from compiler/rustc_mir/src/dataflow/impls/borrows.rs
rename to compiler/rustc_borrowck/src/dataflow.rs
index c92cff1433f1a..1e660ece90868 100644
--- a/compiler/rustc_mir/src/dataflow/impls/borrows.rs
+++ b/compiler/rustc_borrowck/src/dataflow.rs
@@ -1,17 +1,110 @@
-use rustc_middle::mir::{self, Body, Location, Place};
-use rustc_middle::ty::RegionVid;
-use rustc_middle::ty::TyCtxt;
-
 use rustc_data_structures::fx::FxHashMap;
 use rustc_index::bit_set::BitSet;
+use rustc_middle::mir::{self, BasicBlock, Body, Location, Place};
+use rustc_middle::ty::RegionVid;
+use rustc_middle::ty::TyCtxt;
+use rustc_mir_dataflow::impls::{EverInitializedPlaces, MaybeUninitializedPlaces};
+use rustc_mir_dataflow::ResultsVisitable;
+use rustc_mir_dataflow::{self, fmt::DebugWithContext, GenKill};
+use rustc_mir_dataflow::{Analysis, Direction, Results};
+use std::fmt;
+use std::iter;
 
-use crate::borrow_check::{
+use crate::{
     places_conflict, BorrowSet, PlaceConflictBias, PlaceExt, RegionInferenceContext, ToRegionVid,
 };
-use crate::dataflow::{self, fmt::DebugWithContext, GenKill};
 
-use std::fmt;
-use std::iter;
+/// A tuple with named fields that can hold either the results or the transient state of the
+/// dataflow analyses used by the borrow checker.
+#[derive(Debug)]
+pub struct BorrowckAnalyses<B, U, E> {
+    pub borrows: B,
+    pub uninits: U,
+    pub ever_inits: E,
+}
+
+/// The results of the dataflow analyses used by the borrow checker.
+pub type BorrowckResults<'mir, 'tcx> = BorrowckAnalyses<
+    Results<'tcx, Borrows<'mir, 'tcx>>,
+    Results<'tcx, MaybeUninitializedPlaces<'mir, 'tcx>>,
+    Results<'tcx, EverInitializedPlaces<'mir, 'tcx>>,
+>;
+
+/// The transient state of the dataflow analyses used by the borrow checker.
+pub type BorrowckFlowState<'mir, 'tcx> =
+    <BorrowckResults<'mir, 'tcx> as ResultsVisitable<'tcx>>::FlowState;
+
+macro_rules! impl_visitable {
+    ( $(
+        $T:ident { $( $field:ident : $A:ident ),* $(,)? }
+    )* ) => { $(
+        impl<'tcx, $($A),*, D: Direction> ResultsVisitable<'tcx> for $T<$( Results<'tcx, $A> ),*>
+        where
+            $( $A: Analysis<'tcx, Direction = D>, )*
+        {
+            type Direction = D;
+            type FlowState = $T<$( $A::Domain ),*>;
+
+            fn new_flow_state(&self, body: &mir::Body<'tcx>) -> Self::FlowState {
+                $T {
+                    $( $field: self.$field.analysis.bottom_value(body) ),*
+                }
+            }
+
+            fn reset_to_block_entry(
+                &self,
+                state: &mut Self::FlowState,
+                block: BasicBlock,
+            ) {
+                $( state.$field.clone_from(&self.$field.entry_set_for_block(block)); )*
+            }
+
+            fn reconstruct_before_statement_effect(
+                &self,
+                state: &mut Self::FlowState,
+                stmt: &mir::Statement<'tcx>,
+                loc: Location,
+            ) {
+                $( self.$field.analysis
+                    .apply_before_statement_effect(&mut state.$field, stmt, loc); )*
+            }
+
+            fn reconstruct_statement_effect(
+                &self,
+                state: &mut Self::FlowState,
+                stmt: &mir::Statement<'tcx>,
+                loc: Location,
+            ) {
+                $( self.$field.analysis
+                    .apply_statement_effect(&mut state.$field, stmt, loc); )*
+            }
+
+            fn reconstruct_before_terminator_effect(
+                &self,
+                state: &mut Self::FlowState,
+                term: &mir::Terminator<'tcx>,
+                loc: Location,
+            ) {
+                $( self.$field.analysis
+                    .apply_before_terminator_effect(&mut state.$field, term, loc); )*
+            }
+
+            fn reconstruct_terminator_effect(
+                &self,
+                state: &mut Self::FlowState,
+                term: &mir::Terminator<'tcx>,
+                loc: Location,
+            ) {
+                $( self.$field.analysis
+                    .apply_terminator_effect(&mut state.$field, term, loc); )*
+            }
+        }
+    )* }
+}
+
+impl_visitable! {
+    BorrowckAnalyses { borrows: B, uninits: U, ever_inits: E }
+}
 
 rustc_index::newtype_index! {
     pub struct BorrowIndex {
@@ -230,7 +323,7 @@ impl<'a, 'tcx> Borrows<'a, 'tcx> {
     }
 }
 
-impl<'tcx> dataflow::AnalysisDomain<'tcx> for Borrows<'_, 'tcx> {
+impl<'tcx> rustc_mir_dataflow::AnalysisDomain<'tcx> for Borrows<'_, 'tcx> {
     type Domain = BitSet<BorrowIndex>;
 
     const NAME: &'static str = "borrows";
@@ -246,7 +339,7 @@ impl<'tcx> dataflow::AnalysisDomain<'tcx> for Borrows<'_, 'tcx> {
     }
 }
 
-impl<'tcx> dataflow::GenKillAnalysis<'tcx> for Borrows<'_, 'tcx> {
+impl<'tcx> rustc_mir_dataflow::GenKillAnalysis<'tcx> for Borrows<'_, 'tcx> {
     type Idx = BorrowIndex;
 
     fn before_statement_effect(
diff --git a/compiler/rustc_mir/src/borrow_check/def_use.rs b/compiler/rustc_borrowck/src/def_use.rs
similarity index 100%
rename from compiler/rustc_mir/src/borrow_check/def_use.rs
rename to compiler/rustc_borrowck/src/def_use.rs
diff --git a/compiler/rustc_mir/src/borrow_check/diagnostics/bound_region_errors.rs b/compiler/rustc_borrowck/src/diagnostics/bound_region_errors.rs
similarity index 99%
rename from compiler/rustc_mir/src/borrow_check/diagnostics/bound_region_errors.rs
rename to compiler/rustc_borrowck/src/diagnostics/bound_region_errors.rs
index ac30093ba8260..76e779bfec608 100644
--- a/compiler/rustc_mir/src/borrow_check/diagnostics/bound_region_errors.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/bound_region_errors.rs
@@ -14,8 +14,8 @@ use rustc_traits::{type_op_ascribe_user_type_with_span, type_op_prove_predicate_
 use std::fmt;
 use std::rc::Rc;
 
-use crate::borrow_check::region_infer::values::RegionElement;
-use crate::borrow_check::MirBorrowckCtxt;
+use crate::region_infer::values::RegionElement;
+use crate::MirBorrowckCtxt;
 
 #[derive(Clone)]
 crate struct UniverseInfo<'tcx>(UniverseInfoInner<'tcx>);
diff --git a/compiler/rustc_mir/src/borrow_check/diagnostics/conflict_errors.rs b/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs
similarity index 99%
rename from compiler/rustc_mir/src/borrow_check/diagnostics/conflict_errors.rs
rename to compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs
index 6561fe37c1c47..ce1e7c14b1ff6 100644
--- a/compiler/rustc_mir/src/borrow_check/diagnostics/conflict_errors.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs
@@ -10,16 +10,16 @@ use rustc_middle::mir::{
     ProjectionElem, Rvalue, Statement, StatementKind, Terminator, TerminatorKind, VarBindingForm,
 };
 use rustc_middle::ty::{self, suggest_constraining_type_param, Ty};
+use rustc_mir_dataflow::drop_flag_effects;
+use rustc_mir_dataflow::move_paths::{MoveOutIndex, MovePathIndex};
 use rustc_span::source_map::DesugaringKind;
 use rustc_span::symbol::sym;
 use rustc_span::{BytePos, MultiSpan, Span, DUMMY_SP};
 use rustc_trait_selection::infer::InferCtxtExt;
 
-use crate::dataflow::drop_flag_effects;
-use crate::dataflow::indexes::{MoveOutIndex, MovePathIndex};
-use crate::util::borrowck_errors;
+use crate::borrowck_errors;
 
-use crate::borrow_check::{
+use crate::{
     borrow_set::BorrowData, diagnostics::Instance, prefixes::IsPrefixOf,
     InitializationRequiringAction, MirBorrowckCtxt, PrefixSet, WriteKind,
 };
@@ -49,7 +49,7 @@ enum StorageDeadOrDrop<'tcx> {
 }
 
 impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
-    pub(in crate::borrow_check) fn report_use_of_moved_or_uninitialized(
+    pub(crate) fn report_use_of_moved_or_uninitialized(
         &mut self,
         location: Location,
         desired_action: InitializationRequiringAction,
@@ -441,7 +441,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
         }
     }
 
-    pub(in crate::borrow_check) fn report_move_out_while_borrowed(
+    pub(crate) fn report_move_out_while_borrowed(
         &mut self,
         location: Location,
         (place, span): (Place<'tcx>, Span),
@@ -489,7 +489,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
         err.buffer(&mut self.errors_buffer);
     }
 
-    pub(in crate::borrow_check) fn report_use_while_mutably_borrowed(
+    pub(crate) fn report_use_while_mutably_borrowed(
         &mut self,
         location: Location,
         (place, _span): (Place<'tcx>, Span),
@@ -535,7 +535,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
         err
     }
 
-    pub(in crate::borrow_check) fn report_conflicting_borrow(
+    pub(crate) fn report_conflicting_borrow(
         &mut self,
         location: Location,
         (place, span): (Place<'tcx>, Span),
@@ -798,7 +798,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
     /// cannot borrow `a.u` (via `a.u.z.c`) as immutable because it is also borrowed as
     /// mutable (via `a.u.s.b`) [E0502]
     /// ```
-    pub(in crate::borrow_check) fn describe_place_for_conflicting_borrow(
+    pub(crate) fn describe_place_for_conflicting_borrow(
         &self,
         first_borrowed_place: Place<'tcx>,
         second_borrowed_place: Place<'tcx>,
@@ -875,7 +875,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
     /// short a lifetime. (But sometimes it is more useful to report
     /// it as a more direct conflict between the execution of a
     /// `Drop::drop` with an aliasing borrow.)
-    pub(in crate::borrow_check) fn report_borrowed_value_does_not_live_long_enough(
+    pub(crate) fn report_borrowed_value_does_not_live_long_enough(
         &mut self,
         location: Location,
         borrow: &BorrowData<'tcx>,
@@ -1634,7 +1634,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
         (result, reinits_reachable)
     }
 
-    pub(in crate::borrow_check) fn report_illegal_mutation_of_borrowed(
+    pub(crate) fn report_illegal_mutation_of_borrowed(
         &mut self,
         location: Location,
         (place, span): (Place<'tcx>, Span),
@@ -1695,7 +1695,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
             Some((method_did, method_substs)),
         ) = (
             &self.body[loan.reserve_location.block].terminator,
-            crate::util::find_self_call(
+            rustc_const_eval::util::find_self_call(
                 tcx,
                 self.body,
                 loan.assigned_place.local,
@@ -1726,7 +1726,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
     /// assigned; `err_place` is a place providing a reason why
     /// `place` is not mutable (e.g., the non-`mut` local `x` in an
     /// assignment to `x.f`).
-    pub(in crate::borrow_check) fn report_illegal_reassignment(
+    pub(crate) fn report_illegal_reassignment(
         &mut self,
         _location: Location,
         (place, span): (Place<'tcx>, Span),
@@ -2226,7 +2226,7 @@ enum AnnotatedBorrowFnSignature<'tcx> {
 impl<'tcx> AnnotatedBorrowFnSignature<'tcx> {
     /// Annotate the provided diagnostic with information about borrow from the fn signature that
     /// helps explain.
-    pub(in crate::borrow_check) fn emit(
+    pub(crate) fn emit(
         &self,
         cx: &mut MirBorrowckCtxt<'_, 'tcx>,
         diag: &mut DiagnosticBuilder<'_>,
diff --git a/compiler/rustc_mir/src/borrow_check/diagnostics/explain_borrow.rs b/compiler/rustc_borrowck/src/diagnostics/explain_borrow.rs
similarity index 98%
rename from compiler/rustc_mir/src/borrow_check/diagnostics/explain_borrow.rs
rename to compiler/rustc_borrowck/src/diagnostics/explain_borrow.rs
index f40a2db330a97..2d12a682e7ae6 100644
--- a/compiler/rustc_mir/src/borrow_check/diagnostics/explain_borrow.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/explain_borrow.rs
@@ -15,8 +15,8 @@ use rustc_middle::ty::{self, RegionVid, TyCtxt};
 use rustc_span::symbol::Symbol;
 use rustc_span::Span;
 
-use crate::borrow_check::region_infer::BlameConstraint;
-use crate::borrow_check::{
+use crate::region_infer::BlameConstraint;
+use crate::{
     borrow_set::BorrowData, nll::ConstraintDescription, region_infer::Cause, MirBorrowckCtxt,
     WriteKind,
 };
@@ -24,7 +24,7 @@ use crate::borrow_check::{
 use super::{find_use, RegionName, UseSpans};
 
 #[derive(Debug)]
-pub(in crate::borrow_check) enum BorrowExplanation {
+pub(crate) enum BorrowExplanation {
     UsedLater(LaterUseKind, Span, Option<Span>),
     UsedLaterInLoop(LaterUseKind, Span, Option<Span>),
     UsedLaterWhenDropped {
@@ -43,7 +43,7 @@ pub(in crate::borrow_check) enum BorrowExplanation {
 }
 
 #[derive(Clone, Copy, Debug)]
-pub(in crate::borrow_check) enum LaterUseKind {
+pub(crate) enum LaterUseKind {
     TraitCapture,
     ClosureCapture,
     Call,
@@ -52,13 +52,13 @@ pub(in crate::borrow_check) enum LaterUseKind {
 }
 
 impl BorrowExplanation {
-    pub(in crate::borrow_check) fn is_explained(&self) -> bool {
+    pub(crate) fn is_explained(&self) -> bool {
         match self {
             BorrowExplanation::Unexplained => false,
             _ => true,
         }
     }
-    pub(in crate::borrow_check) fn add_explanation_to_diagnostic<'tcx>(
+    pub(crate) fn add_explanation_to_diagnostic<'tcx>(
         &self,
         tcx: TyCtxt<'tcx>,
         body: &Body<'tcx>,
@@ -267,7 +267,7 @@ impl BorrowExplanation {
             _ => {}
         }
     }
-    pub(in crate::borrow_check) fn add_lifetime_bound_suggestion_to_diagnostic(
+    pub(crate) fn add_lifetime_bound_suggestion_to_diagnostic(
         &self,
         err: &mut DiagnosticBuilder<'_>,
         category: &ConstraintCategory,
@@ -326,7 +326,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
     ///   - second half is the place being accessed
     ///
     /// [d]: https://rust-lang.github.io/rfcs/2094-nll.html#leveraging-intuition-framing-errors-in-terms-of-points
-    pub(in crate::borrow_check) fn explain_why_borrow_contains_point(
+    pub(crate) fn explain_why_borrow_contains_point(
         &self,
         location: Location,
         borrow: &BorrowData<'tcx>,
diff --git a/compiler/rustc_mir/src/borrow_check/diagnostics/find_use.rs b/compiler/rustc_borrowck/src/diagnostics/find_use.rs
similarity index 99%
rename from compiler/rustc_mir/src/borrow_check/diagnostics/find_use.rs
rename to compiler/rustc_borrowck/src/diagnostics/find_use.rs
index 8d8cdfb52934c..ab4536f00fc42 100644
--- a/compiler/rustc_mir/src/borrow_check/diagnostics/find_use.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/find_use.rs
@@ -1,7 +1,7 @@
 use std::collections::VecDeque;
 use std::rc::Rc;
 
-use crate::borrow_check::{
+use crate::{
     def_use::{self, DefUse},
     nll::ToRegionVid,
     region_infer::{Cause, RegionInferenceContext},
diff --git a/compiler/rustc_mir/src/borrow_check/diagnostics/mod.rs b/compiler/rustc_borrowck/src/diagnostics/mod.rs
similarity index 99%
rename from compiler/rustc_mir/src/borrow_check/diagnostics/mod.rs
rename to compiler/rustc_borrowck/src/diagnostics/mod.rs
index 55c6410ed3204..50130dc2a27ed 100644
--- a/compiler/rustc_mir/src/borrow_check/diagnostics/mod.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/mod.rs
@@ -12,6 +12,7 @@ use rustc_middle::mir::{
 };
 use rustc_middle::ty::print::Print;
 use rustc_middle::ty::{self, DefIdTree, Instance, Ty, TyCtxt};
+use rustc_mir_dataflow::move_paths::{InitLocation, LookupResult};
 use rustc_span::{
     hygiene::{DesugaringKind, ForLoopLoc},
     symbol::sym,
@@ -21,7 +22,6 @@ use rustc_target::abi::VariantIdx;
 
 use super::borrow_set::BorrowData;
 use super::MirBorrowckCtxt;
-use crate::dataflow::move_paths::{InitLocation, LookupResult};
 
 mod find_use;
 mod outlives_suggestion;
@@ -900,8 +900,12 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
         }) = &self.body[location.block].terminator
         {
             let (method_did, method_substs) = if let Some(info) =
-                crate::util::find_self_call(self.infcx.tcx, &self.body, target_temp, location.block)
-            {
+                rustc_const_eval::util::find_self_call(
+                    self.infcx.tcx,
+                    &self.body,
+                    target_temp,
+                    location.block,
+                ) {
                 info
             } else {
                 return normal_ret;
diff --git a/compiler/rustc_mir/src/borrow_check/diagnostics/move_errors.rs b/compiler/rustc_borrowck/src/diagnostics/move_errors.rs
similarity index 99%
rename from compiler/rustc_mir/src/borrow_check/diagnostics/move_errors.rs
rename to compiler/rustc_borrowck/src/diagnostics/move_errors.rs
index 66e06325fa982..3c11408458629 100644
--- a/compiler/rustc_mir/src/borrow_check/diagnostics/move_errors.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/move_errors.rs
@@ -2,16 +2,16 @@ use rustc_errors::{Applicability, DiagnosticBuilder};
 use rustc_infer::infer::TyCtxtInferExt;
 use rustc_middle::mir::*;
 use rustc_middle::ty;
+use rustc_mir_dataflow::move_paths::{
+    IllegalMoveOrigin, IllegalMoveOriginKind, LookupResult, MoveError, MovePathIndex,
+};
 use rustc_span::source_map::DesugaringKind;
 use rustc_span::{sym, Span, DUMMY_SP};
 use rustc_trait_selection::traits::type_known_to_meet_bound_modulo_regions;
 
-use crate::borrow_check::diagnostics::UseSpans;
-use crate::borrow_check::prefixes::PrefixSet;
-use crate::borrow_check::MirBorrowckCtxt;
-use crate::dataflow::move_paths::{
-    IllegalMoveOrigin, IllegalMoveOriginKind, LookupResult, MoveError, MovePathIndex,
-};
+use crate::diagnostics::UseSpans;
+use crate::prefixes::PrefixSet;
+use crate::MirBorrowckCtxt;
 
 // Often when desugaring a pattern match we may have many individual moves in
 // MIR that are all part of one operation from the user's point-of-view. For
diff --git a/compiler/rustc_mir/src/borrow_check/diagnostics/mutability_errors.rs b/compiler/rustc_borrowck/src/diagnostics/mutability_errors.rs
similarity index 99%
rename from compiler/rustc_mir/src/borrow_check/diagnostics/mutability_errors.rs
rename to compiler/rustc_borrowck/src/diagnostics/mutability_errors.rs
index 4e079ed865ac3..7ca72cbed8de8 100644
--- a/compiler/rustc_mir/src/borrow_check/diagnostics/mutability_errors.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/mutability_errors.rs
@@ -14,9 +14,9 @@ use rustc_span::source_map::DesugaringKind;
 use rustc_span::symbol::{kw, Symbol};
 use rustc_span::{BytePos, Span};
 
-use crate::borrow_check::diagnostics::BorrowedContentSource;
-use crate::borrow_check::MirBorrowckCtxt;
-use crate::util::collect_writes::FindAssignments;
+use crate::diagnostics::BorrowedContentSource;
+use crate::MirBorrowckCtxt;
+use rustc_const_eval::util::collect_writes::FindAssignments;
 use rustc_errors::{Applicability, DiagnosticBuilder};
 
 #[derive(Copy, Clone, Debug, Eq, PartialEq)]
diff --git a/compiler/rustc_mir/src/borrow_check/diagnostics/outlives_suggestion.rs b/compiler/rustc_borrowck/src/diagnostics/outlives_suggestion.rs
similarity index 99%
rename from compiler/rustc_mir/src/borrow_check/diagnostics/outlives_suggestion.rs
rename to compiler/rustc_borrowck/src/diagnostics/outlives_suggestion.rs
index 7dc3434bf3338..9de0c62f186c0 100644
--- a/compiler/rustc_mir/src/borrow_check/diagnostics/outlives_suggestion.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/outlives_suggestion.rs
@@ -1,16 +1,14 @@
 //! Contains utilities for generating suggestions for borrowck errors related to unsatisfied
 //! outlives constraints.
 
-use std::collections::BTreeMap;
-
 use rustc_data_structures::fx::FxHashSet;
 use rustc_errors::DiagnosticBuilder;
 use rustc_middle::ty::RegionVid;
-use tracing::debug;
-
 use smallvec::SmallVec;
+use std::collections::BTreeMap;
+use tracing::debug;
 
-use crate::borrow_check::MirBorrowckCtxt;
+use crate::MirBorrowckCtxt;
 
 use super::{ErrorConstraintInfo, RegionName, RegionNameSource};
 
diff --git a/compiler/rustc_mir/src/borrow_check/diagnostics/region_errors.rs b/compiler/rustc_borrowck/src/diagnostics/region_errors.rs
similarity index 99%
rename from compiler/rustc_mir/src/borrow_check/diagnostics/region_errors.rs
rename to compiler/rustc_borrowck/src/diagnostics/region_errors.rs
index cbb8f064bb81a..57d2a3c5ce91b 100644
--- a/compiler/rustc_mir/src/borrow_check/diagnostics/region_errors.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/region_errors.rs
@@ -11,10 +11,10 @@ use rustc_middle::ty::{self, RegionVid, Ty};
 use rustc_span::symbol::{kw, sym};
 use rustc_span::{BytePos, Span};
 
-use crate::util::borrowck_errors;
+use crate::borrowck_errors;
 
-use crate::borrow_check::region_infer::BlameConstraint;
-use crate::borrow_check::{
+use crate::region_infer::BlameConstraint;
+use crate::{
     nll::ConstraintDescription,
     region_infer::{values::RegionElement, TypeTest},
     universal_regions::DefiningTy,
@@ -152,7 +152,7 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
     }
 
     /// Produces nice borrowck error diagnostics for all the errors collected in `nll_errors`.
-    pub(in crate::borrow_check) fn report_region_errors(&mut self, nll_errors: RegionErrors<'tcx>) {
+    pub(crate) fn report_region_errors(&mut self, nll_errors: RegionErrors<'tcx>) {
         // Iterate through all the errors, producing a diagnostic for each one. The diagnostics are
         // buffered in the `MirBorrowckCtxt`.
 
@@ -265,7 +265,7 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
     /// ```
     ///
     /// Here we would be invoked with `fr = 'a` and `outlived_fr = `'b`.
-    pub(in crate::borrow_check) fn report_region_error(
+    pub(crate) fn report_region_error(
         &mut self,
         fr: RegionVid,
         fr_origin: NllRegionVariableOrigin,
diff --git a/compiler/rustc_mir/src/borrow_check/diagnostics/region_name.rs b/compiler/rustc_borrowck/src/diagnostics/region_name.rs
similarity index 99%
rename from compiler/rustc_mir/src/borrow_check/diagnostics/region_name.rs
rename to compiler/rustc_borrowck/src/diagnostics/region_name.rs
index 1f168c612f167..5edb52b0b650d 100644
--- a/compiler/rustc_mir/src/borrow_check/diagnostics/region_name.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/region_name.rs
@@ -10,7 +10,7 @@ use rustc_middle::ty::{self, RegionVid, Ty};
 use rustc_span::symbol::{kw, sym, Ident, Symbol};
 use rustc_span::{Span, DUMMY_SP};
 
-use crate::borrow_check::{nll::ToRegionVid, universal_regions::DefiningTy, MirBorrowckCtxt};
+use crate::{nll::ToRegionVid, universal_regions::DefiningTy, MirBorrowckCtxt};
 
 /// A name for a particular region used in emitting diagnostics. This name could be a generated
 /// name like `'1`, a name used by the user like `'a`, or a name like `'static`.
diff --git a/compiler/rustc_mir/src/borrow_check/diagnostics/var_name.rs b/compiler/rustc_borrowck/src/diagnostics/var_name.rs
similarity index 97%
rename from compiler/rustc_mir/src/borrow_check/diagnostics/var_name.rs
rename to compiler/rustc_borrowck/src/diagnostics/var_name.rs
index 4abc623fc5f37..00f6280675355 100644
--- a/compiler/rustc_mir/src/borrow_check/diagnostics/var_name.rs
+++ b/compiler/rustc_borrowck/src/diagnostics/var_name.rs
@@ -1,5 +1,5 @@
-use crate::borrow_check::Upvar;
-use crate::borrow_check::{nll::ToRegionVid, region_infer::RegionInferenceContext};
+use crate::Upvar;
+use crate::{nll::ToRegionVid, region_infer::RegionInferenceContext};
 use rustc_index::vec::{Idx, IndexVec};
 use rustc_middle::mir::{Body, Local};
 use rustc_middle::ty::{RegionVid, TyCtxt};
diff --git a/compiler/rustc_mir/src/borrow_check/facts.rs b/compiler/rustc_borrowck/src/facts.rs
similarity index 95%
rename from compiler/rustc_mir/src/borrow_check/facts.rs
rename to compiler/rustc_borrowck/src/facts.rs
index 215dead5bd15e..86b719bdfa0c7 100644
--- a/compiler/rustc_mir/src/borrow_check/facts.rs
+++ b/compiler/rustc_borrowck/src/facts.rs
@@ -1,10 +1,11 @@
-use crate::borrow_check::location::{LocationIndex, LocationTable};
-use crate::dataflow::indexes::{BorrowIndex, MovePathIndex};
+use crate::location::{LocationIndex, LocationTable};
+use crate::BorrowIndex;
 use polonius_engine::AllFacts as PoloniusFacts;
 use polonius_engine::Atom;
 use rustc_index::vec::Idx;
 use rustc_middle::mir::Local;
 use rustc_middle::ty::{RegionVid, TyCtxt};
+use rustc_mir_dataflow::move_paths::MovePathIndex;
 use std::error::Error;
 use std::fmt::Debug;
 use std::fs::{self, File};
@@ -100,12 +101,6 @@ impl Atom for LocationIndex {
     }
 }
 
-impl Atom for MovePathIndex {
-    fn index(self) -> usize {
-        Idx::index(self)
-    }
-}
-
 struct FactWriter<'w> {
     location_table: &'w LocationTable,
     dir: &'w Path,
diff --git a/compiler/rustc_mir/src/borrow_check/invalidation.rs b/compiler/rustc_borrowck/src/invalidation.rs
similarity index 98%
rename from compiler/rustc_mir/src/borrow_check/invalidation.rs
rename to compiler/rustc_borrowck/src/invalidation.rs
index b83a427f47574..016fe0bb6dedf 100644
--- a/compiler/rustc_mir/src/borrow_check/invalidation.rs
+++ b/compiler/rustc_borrowck/src/invalidation.rs
@@ -7,12 +7,10 @@ use rustc_middle::mir::{Statement, StatementKind};
 use rustc_middle::ty::TyCtxt;
 use std::iter;
 
-use crate::dataflow::indexes::BorrowIndex;
-
-use crate::borrow_check::{
+use crate::{
     borrow_set::BorrowSet, facts::AllFacts, location::LocationTable, path_utils::*, AccessDepth,
-    Activation, ArtificialField, Deep, JustWrite, LocalMutationIsAllowed, MutateMode, Read,
-    ReadKind, ReadOrWrite, Reservation, Shallow, Write, WriteAndRead, WriteKind,
+    Activation, ArtificialField, BorrowIndex, Deep, JustWrite, LocalMutationIsAllowed, MutateMode,
+    Read, ReadKind, ReadOrWrite, Reservation, Shallow, Write, WriteAndRead, WriteKind,
 };
 
 pub(super) fn generate_invalidates<'tcx>(
diff --git a/compiler/rustc_mir/src/borrow_check/mod.rs b/compiler/rustc_borrowck/src/lib.rs
similarity index 98%
rename from compiler/rustc_mir/src/borrow_check/mod.rs
rename to compiler/rustc_borrowck/src/lib.rs
index 1dcb067656258..4e4b8a953cd12 100644
--- a/compiler/rustc_mir/src/borrow_check/mod.rs
+++ b/compiler/rustc_borrowck/src/lib.rs
@@ -1,5 +1,23 @@
 //! This query borrow-checks the MIR to (further) ensure it is not broken.
 
+#![feature(bool_to_option)]
+#![feature(box_patterns)]
+#![feature(const_panic)]
+#![feature(crate_visibility_modifier)]
+#![feature(format_args_capture)]
+#![feature(in_band_lifetimes)]
+#![feature(iter_zip)]
+#![feature(min_specialization)]
+#![feature(stmt_expr_attributes)]
+#![feature(trusted_step)]
+#![feature(try_blocks)]
+#![recursion_limit = "256"]
+
+#[macro_use]
+extern crate rustc_middle;
+#[macro_use]
+extern crate tracing;
+
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_data_structures::graph::dominators::Dominators;
 use rustc_errors::{Applicability, Diagnostic, DiagnosticBuilder, ErrorReported};
@@ -29,14 +47,13 @@ use std::iter;
 use std::mem;
 use std::rc::Rc;
 
-use crate::dataflow;
-use crate::dataflow::impls::{
-    Borrows, EverInitializedPlaces, MaybeInitializedPlaces, MaybeUninitializedPlaces,
+use rustc_mir_dataflow::impls::{
+    EverInitializedPlaces, MaybeInitializedPlaces, MaybeUninitializedPlaces,
 };
-use crate::dataflow::indexes::{BorrowIndex, InitIndex, MoveOutIndex, MovePathIndex};
-use crate::dataflow::move_paths::{InitLocation, LookupResult, MoveData, MoveError};
-use crate::dataflow::MoveDataParamEnv;
-use crate::dataflow::{Analysis, BorrowckFlowState as Flows, BorrowckResults};
+use rustc_mir_dataflow::move_paths::{InitIndex, MoveOutIndex, MovePathIndex};
+use rustc_mir_dataflow::move_paths::{InitLocation, LookupResult, MoveData, MoveError};
+use rustc_mir_dataflow::Analysis;
+use rustc_mir_dataflow::MoveDataParamEnv;
 
 use self::diagnostics::{AccessKind, RegionName};
 use self::location::LocationTable;
@@ -47,9 +64,10 @@ use facts::AllFacts;
 use self::path_utils::*;
 
 mod borrow_set;
+mod borrowck_errors;
 mod constraint_generation;
 mod constraints;
-pub mod consumers;
+mod dataflow;
 mod def_use;
 mod diagnostics;
 mod facts;
@@ -67,15 +85,19 @@ mod type_check;
 mod universal_regions;
 mod used_muts;
 
-crate use borrow_set::{BorrowData, BorrowSet};
-crate use nll::{PoloniusOutput, ToRegionVid};
-crate use place_ext::PlaceExt;
-crate use places_conflict::{places_conflict, PlaceConflictBias};
-crate use region_infer::RegionInferenceContext;
+// A public API provided for the Rust compiler consumers.
+pub mod consumers;
+
+use borrow_set::{BorrowData, BorrowSet};
+use dataflow::{BorrowIndex, BorrowckFlowState as Flows, BorrowckResults, Borrows};
+use nll::{PoloniusOutput, ToRegionVid};
+use place_ext::PlaceExt;
+use places_conflict::{places_conflict, PlaceConflictBias};
+use region_infer::RegionInferenceContext;
 
 // FIXME(eddyb) perhaps move this somewhere more centrally.
 #[derive(Debug)]
-crate struct Upvar<'tcx> {
+struct Upvar<'tcx> {
     place: CapturedPlace<'tcx>,
 
     /// If true, the capture is behind a reference.
@@ -352,7 +374,7 @@ fn do_mir_borrowck<'a, 'tcx>(
 
     mbcx.report_move_errors(move_errors);
 
-    dataflow::visit_results(
+    rustc_mir_dataflow::visit_results(
         &body,
         traversal::reverse_postorder(&body).map(|(bb, _)| bb),
         &results,
@@ -495,8 +517,8 @@ pub struct BodyWithBorrowckFacts<'tcx> {
     pub location_table: LocationTable,
 }
 
-crate struct MirBorrowckCtxt<'cx, 'tcx> {
-    crate infcx: &'cx InferCtxt<'cx, 'tcx>,
+struct MirBorrowckCtxt<'cx, 'tcx> {
+    infcx: &'cx InferCtxt<'cx, 'tcx>,
     param_env: ParamEnv<'tcx>,
     body: &'cx Body<'tcx>,
     move_data: &'cx MoveData<'tcx>,
@@ -594,7 +616,7 @@ crate struct MirBorrowckCtxt<'cx, 'tcx> {
 // 2. loans made in overlapping scopes do not conflict
 // 3. assignments do not affect things loaned out as immutable
 // 4. moves do not affect things loaned out in any way
-impl<'cx, 'tcx> dataflow::ResultsVisitor<'cx, 'tcx> for MirBorrowckCtxt<'cx, 'tcx> {
+impl<'cx, 'tcx> rustc_mir_dataflow::ResultsVisitor<'cx, 'tcx> for MirBorrowckCtxt<'cx, 'tcx> {
     type FlowState = Flows<'cx, 'tcx>;
 
     fn visit_statement_before_primary_effect(
@@ -2344,7 +2366,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
     /// then returns the index of the field being projected. Note that this closure will always
     /// be `self` in the current MIR, because that is the only time we directly access the fields
     /// of a closure type.
-    pub fn is_upvar_field_projection(&self, place_ref: PlaceRef<'tcx>) -> Option<Field> {
+    fn is_upvar_field_projection(&self, place_ref: PlaceRef<'tcx>) -> Option<Field> {
         path_utils::is_upvar_field_projection(self.infcx.tcx, &self.upvars, place_ref, self.body())
     }
 }
diff --git a/compiler/rustc_mir/src/borrow_check/location.rs b/compiler/rustc_borrowck/src/location.rs
similarity index 100%
rename from compiler/rustc_mir/src/borrow_check/location.rs
rename to compiler/rustc_borrowck/src/location.rs
diff --git a/compiler/rustc_mir/src/borrow_check/member_constraints.rs b/compiler/rustc_borrowck/src/member_constraints.rs
similarity index 100%
rename from compiler/rustc_mir/src/borrow_check/member_constraints.rs
rename to compiler/rustc_borrowck/src/member_constraints.rs
diff --git a/compiler/rustc_mir/src/borrow_check/nll.rs b/compiler/rustc_borrowck/src/nll.rs
similarity index 95%
rename from compiler/rustc_mir/src/borrow_check/nll.rs
rename to compiler/rustc_borrowck/src/nll.rs
index 66ca94d3b415d..8b2c0362261ca 100644
--- a/compiler/rustc_mir/src/borrow_check/nll.rs
+++ b/compiler/rustc_borrowck/src/nll.rs
@@ -4,6 +4,7 @@ use rustc_data_structures::vec_map::VecMap;
 use rustc_errors::Diagnostic;
 use rustc_index::vec::IndexVec;
 use rustc_infer::infer::InferCtxt;
+use rustc_middle::mir::{create_dump_file, dump_enabled, dump_mir, PassWhere};
 use rustc_middle::mir::{
     BasicBlock, Body, ClosureOutlivesSubject, ClosureRegionRequirements, LocalKind, Location,
     Promoted,
@@ -17,16 +18,13 @@ use std::path::PathBuf;
 use std::rc::Rc;
 use std::str::FromStr;
 
-use self::mir_util::PassWhere;
 use polonius_engine::{Algorithm, Output};
 
-use crate::dataflow::impls::MaybeInitializedPlaces;
-use crate::dataflow::move_paths::{InitKind, InitLocation, MoveData};
-use crate::dataflow::ResultsCursor;
-use crate::util as mir_util;
-use crate::util::pretty;
+use rustc_mir_dataflow::impls::MaybeInitializedPlaces;
+use rustc_mir_dataflow::move_paths::{InitKind, InitLocation, MoveData};
+use rustc_mir_dataflow::ResultsCursor;
 
-use crate::borrow_check::{
+use crate::{
     borrow_set::BorrowSet,
     constraint_generation,
     diagnostics::RegionErrors,
@@ -56,7 +54,7 @@ crate struct NllOutput<'tcx> {
 /// Rewrites the regions in the MIR to use NLL variables, also scraping out the set of universal
 /// regions (e.g., region parameters) declared on the function. That set will need to be given to
 /// `compute_regions`.
-pub(in crate::borrow_check) fn replace_regions_in_mir<'cx, 'tcx>(
+pub(crate) fn replace_regions_in_mir<'cx, 'tcx>(
     infcx: &InferCtxt<'cx, 'tcx>,
     param_env: ty::ParamEnv<'tcx>,
     body: &mut Body<'tcx>,
@@ -72,7 +70,7 @@ pub(in crate::borrow_check) fn replace_regions_in_mir<'cx, 'tcx>(
     // Replace all remaining regions with fresh inference variables.
     renumber::renumber_mir(infcx, body, promoted);
 
-    mir_util::dump_mir(infcx.tcx, None, "renumber", &0, body, |_, _| Ok(()));
+    dump_mir(infcx.tcx, None, "renumber", &0, body, |_, _| Ok(()));
 
     universal_regions
 }
@@ -155,7 +153,7 @@ fn populate_polonius_move_facts(
 /// Computes the (non-lexical) regions from the input MIR.
 ///
 /// This may result in errors being reported.
-pub(in crate::borrow_check) fn compute_regions<'cx, 'tcx>(
+pub(crate) fn compute_regions<'cx, 'tcx>(
     infcx: &InferCtxt<'cx, 'tcx>,
     universal_regions: UniversalRegions<'tcx>,
     body: &Body<'tcx>,
@@ -322,11 +320,11 @@ pub(super) fn dump_mir_results<'a, 'tcx>(
     regioncx: &RegionInferenceContext<'tcx>,
     closure_region_requirements: &Option<ClosureRegionRequirements<'_>>,
 ) {
-    if !mir_util::dump_enabled(infcx.tcx, "nll", body.source.def_id()) {
+    if !dump_enabled(infcx.tcx, "nll", body.source.def_id()) {
         return;
     }
 
-    mir_util::dump_mir(infcx.tcx, None, "nll", &0, body, |pass_where, out| {
+    dump_mir(infcx.tcx, None, "nll", &0, body, |pass_where, out| {
         match pass_where {
             // Before the CFG, dump out the values for each region variable.
             PassWhere::BeforeCFG => {
@@ -354,14 +352,14 @@ pub(super) fn dump_mir_results<'a, 'tcx>(
     // Also dump the inference graph constraints as a graphviz file.
     let _: io::Result<()> = try {
         let mut file =
-            pretty::create_dump_file(infcx.tcx, "regioncx.all.dot", None, "nll", &0, body.source)?;
+            create_dump_file(infcx.tcx, "regioncx.all.dot", None, "nll", &0, body.source)?;
         regioncx.dump_graphviz_raw_constraints(&mut file)?;
     };
 
     // Also dump the inference graph constraints as a graphviz file.
     let _: io::Result<()> = try {
         let mut file =
-            pretty::create_dump_file(infcx.tcx, "regioncx.scc.dot", None, "nll", &0, body.source)?;
+            create_dump_file(infcx.tcx, "regioncx.scc.dot", None, "nll", &0, body.source)?;
         regioncx.dump_graphviz_scc_constraints(&mut file)?;
     };
 }
diff --git a/compiler/rustc_mir/src/borrow_check/path_utils.rs b/compiler/rustc_borrowck/src/path_utils.rs
similarity index 96%
rename from compiler/rustc_mir/src/borrow_check/path_utils.rs
rename to compiler/rustc_borrowck/src/path_utils.rs
index 80de3b4e363bf..d5d00b467eeed 100644
--- a/compiler/rustc_mir/src/borrow_check/path_utils.rs
+++ b/compiler/rustc_borrowck/src/path_utils.rs
@@ -1,8 +1,8 @@
-use crate::borrow_check::borrow_set::{BorrowData, BorrowSet, TwoPhaseActivation};
-use crate::borrow_check::places_conflict;
-use crate::borrow_check::AccessDepth;
-use crate::borrow_check::Upvar;
-use crate::dataflow::indexes::BorrowIndex;
+use crate::borrow_set::{BorrowData, BorrowSet, TwoPhaseActivation};
+use crate::places_conflict;
+use crate::AccessDepth;
+use crate::BorrowIndex;
+use crate::Upvar;
 use rustc_data_structures::graph::dominators::Dominators;
 use rustc_middle::mir::BorrowKind;
 use rustc_middle::mir::{BasicBlock, Body, Field, Location, Place, PlaceRef, ProjectionElem};
diff --git a/compiler/rustc_mir/src/borrow_check/place_ext.rs b/compiler/rustc_borrowck/src/place_ext.rs
similarity index 98%
rename from compiler/rustc_mir/src/borrow_check/place_ext.rs
rename to compiler/rustc_borrowck/src/place_ext.rs
index 52fac3e53ee65..83ff1595b0be4 100644
--- a/compiler/rustc_mir/src/borrow_check/place_ext.rs
+++ b/compiler/rustc_borrowck/src/place_ext.rs
@@ -1,4 +1,4 @@
-use crate::borrow_check::borrow_set::LocalsStateAtExit;
+use crate::borrow_set::LocalsStateAtExit;
 use rustc_hir as hir;
 use rustc_middle::mir::ProjectionElem;
 use rustc_middle::mir::{Body, Mutability, Place};
diff --git a/compiler/rustc_mir/src/borrow_check/places_conflict.rs b/compiler/rustc_borrowck/src/places_conflict.rs
similarity index 99%
rename from compiler/rustc_mir/src/borrow_check/places_conflict.rs
rename to compiler/rustc_borrowck/src/places_conflict.rs
index d21550a8e1af6..773e9e90b0c6b 100644
--- a/compiler/rustc_mir/src/borrow_check/places_conflict.rs
+++ b/compiler/rustc_borrowck/src/places_conflict.rs
@@ -1,6 +1,6 @@
-use crate::borrow_check::ArtificialField;
-use crate::borrow_check::Overlap;
-use crate::borrow_check::{AccessDepth, Deep, Shallow};
+use crate::ArtificialField;
+use crate::Overlap;
+use crate::{AccessDepth, Deep, Shallow};
 use rustc_hir as hir;
 use rustc_middle::mir::{Body, BorrowKind, Local, Place, PlaceElem, PlaceRef, ProjectionElem};
 use rustc_middle::ty::{self, TyCtxt};
diff --git a/compiler/rustc_mir/src/borrow_check/prefixes.rs b/compiler/rustc_borrowck/src/prefixes.rs
similarity index 100%
rename from compiler/rustc_mir/src/borrow_check/prefixes.rs
rename to compiler/rustc_borrowck/src/prefixes.rs
diff --git a/compiler/rustc_mir/src/borrow_check/region_infer/dump_mir.rs b/compiler/rustc_borrowck/src/region_infer/dump_mir.rs
similarity index 98%
rename from compiler/rustc_mir/src/borrow_check/region_infer/dump_mir.rs
rename to compiler/rustc_borrowck/src/region_infer/dump_mir.rs
index 213ebff12abc0..cfd3acb6bdebd 100644
--- a/compiler/rustc_mir/src/borrow_check/region_infer/dump_mir.rs
+++ b/compiler/rustc_borrowck/src/region_infer/dump_mir.rs
@@ -4,7 +4,7 @@
 //! context internal state.
 
 use super::{OutlivesConstraint, RegionInferenceContext};
-use crate::borrow_check::type_check::Locations;
+use crate::type_check::Locations;
 use rustc_infer::infer::NllRegionVariableOrigin;
 use rustc_middle::ty::TyCtxt;
 use std::io::{self, Write};
diff --git a/compiler/rustc_mir/src/borrow_check/region_infer/graphviz.rs b/compiler/rustc_borrowck/src/region_infer/graphviz.rs
similarity index 98%
rename from compiler/rustc_mir/src/borrow_check/region_infer/graphviz.rs
rename to compiler/rustc_borrowck/src/region_infer/graphviz.rs
index b944d74e6f231..95048d50f117f 100644
--- a/compiler/rustc_mir/src/borrow_check/region_infer/graphviz.rs
+++ b/compiler/rustc_borrowck/src/region_infer/graphviz.rs
@@ -6,7 +6,7 @@ use std::borrow::Cow;
 use std::io::{self, Write};
 
 use super::*;
-use crate::borrow_check::constraints::OutlivesConstraint;
+use crate::constraints::OutlivesConstraint;
 use rustc_graphviz as dot;
 
 impl<'tcx> RegionInferenceContext<'tcx> {
diff --git a/compiler/rustc_mir/src/borrow_check/region_infer/mod.rs b/compiler/rustc_borrowck/src/region_infer/mod.rs
similarity index 99%
rename from compiler/rustc_mir/src/borrow_check/region_infer/mod.rs
rename to compiler/rustc_borrowck/src/region_infer/mod.rs
index a96cdbc13f345..48e45a9b1ce72 100644
--- a/compiler/rustc_mir/src/borrow_check/region_infer/mod.rs
+++ b/compiler/rustc_borrowck/src/region_infer/mod.rs
@@ -17,7 +17,7 @@ use rustc_middle::mir::{
 use rustc_middle::ty::{self, subst::SubstsRef, RegionVid, Ty, TyCtxt, TypeFoldable};
 use rustc_span::Span;
 
-use crate::borrow_check::{
+use crate::{
     constraints::{
         graph::NormalConstraintGraph, ConstraintSccIndex, OutlivesConstraint, OutlivesConstraintSet,
     },
@@ -132,33 +132,33 @@ pub(crate) struct AppliedMemberConstraint {
     ///
     /// The vector if `AppliedMemberConstraint` elements is kept sorted
     /// by this field.
-    pub(in crate::borrow_check) member_region_scc: ConstraintSccIndex,
+    pub(crate) member_region_scc: ConstraintSccIndex,
 
     /// The "best option" that `apply_member_constraint` found -- this was
     /// added as an "ad-hoc" lower-bound to `member_region_scc`.
-    pub(in crate::borrow_check) min_choice: ty::RegionVid,
+    pub(crate) min_choice: ty::RegionVid,
 
     /// The "member constraint index" -- we can find out details about
     /// the constraint from
     /// `set.member_constraints[member_constraint_index]`.
-    pub(in crate::borrow_check) member_constraint_index: NllMemberConstraintIndex,
+    pub(crate) member_constraint_index: NllMemberConstraintIndex,
 }
 
 pub(crate) struct RegionDefinition<'tcx> {
     /// What kind of variable is this -- a free region? existential
     /// variable? etc. (See the `NllRegionVariableOrigin` for more
     /// info.)
-    pub(in crate::borrow_check) origin: NllRegionVariableOrigin,
+    pub(crate) origin: NllRegionVariableOrigin,
 
     /// Which universe is this region variable defined in? This is
     /// most often `ty::UniverseIndex::ROOT`, but when we encounter
     /// forall-quantifiers like `for<'a> { 'a = 'b }`, we would create
     /// the variable for `'a` in a fresh universe that extends ROOT.
-    pub(in crate::borrow_check) universe: ty::UniverseIndex,
+    pub(crate) universe: ty::UniverseIndex,
 
     /// If this is 'static or an early-bound region, then this is
     /// `Some(X)` where `X` is the name of the region.
-    pub(in crate::borrow_check) external_name: Option<ty::Region<'tcx>>,
+    pub(crate) external_name: Option<ty::Region<'tcx>>,
 }
 
 /// N.B., the variants in `Cause` are intentionally ordered. Lower
@@ -245,7 +245,7 @@ impl<'tcx> RegionInferenceContext<'tcx> {
     ///
     /// The `outlives_constraints` and `type_tests` are an initial set
     /// of constraints produced by the MIR type check.
-    pub(in crate::borrow_check) fn new(
+    pub(crate) fn new(
         var_infos: VarInfos,
         universal_regions: Rc<UniversalRegions<'tcx>>,
         placeholder_indices: Rc<PlaceholderIndices>,
@@ -534,7 +534,7 @@ impl<'tcx> RegionInferenceContext<'tcx> {
     /// Once region solving has completed, this function will return
     /// the member constraints that were applied to the value of a given
     /// region `r`. See `AppliedMemberConstraint`.
-    pub(in crate::borrow_check) fn applied_member_constraints(
+    pub(crate) fn applied_member_constraints(
         &self,
         r: impl ToRegionVid,
     ) -> &[AppliedMemberConstraint] {
@@ -1088,7 +1088,7 @@ impl<'tcx> RegionInferenceContext<'tcx> {
     ///   include the CFG anyhow.
     /// - For each `end('x)` element in `'r`, compute the mutual LUB, yielding
     ///   a result `'y`.
-    pub(in crate::borrow_check) fn universal_upper_bound(&self, r: RegionVid) -> RegionVid {
+    pub(crate) fn universal_upper_bound(&self, r: RegionVid) -> RegionVid {
         debug!("universal_upper_bound(r={:?}={})", r, self.region_value_str(r));
 
         // Find the smallest universal region that contains all other
@@ -1115,7 +1115,7 @@ impl<'tcx> RegionInferenceContext<'tcx> {
     /// Therefore, this method should only be used in diagnostic code,
     /// where displaying *some* named universal region is better than
     /// falling back to 'static.
-    pub(in crate::borrow_check) fn approx_universal_upper_bound(&self, r: RegionVid) -> RegionVid {
+    pub(crate) fn approx_universal_upper_bound(&self, r: RegionVid) -> RegionVid {
         debug!("approx_universal_upper_bound(r={:?}={})", r, self.region_value_str(r));
 
         // Find the smallest universal region that contains all other
diff --git a/compiler/rustc_mir/src/borrow_check/region_infer/opaque_types.rs b/compiler/rustc_borrowck/src/region_infer/opaque_types.rs
similarity index 97%
rename from compiler/rustc_mir/src/borrow_check/region_infer/opaque_types.rs
rename to compiler/rustc_borrowck/src/region_infer/opaque_types.rs
index 12fceeff0884c..39b83e5043101 100644
--- a/compiler/rustc_mir/src/borrow_check/region_infer/opaque_types.rs
+++ b/compiler/rustc_borrowck/src/region_infer/opaque_types.rs
@@ -47,7 +47,7 @@ impl<'tcx> RegionInferenceContext<'tcx> {
     /// which has no `external_name` in which case we use `'empty` as the
     /// region to pass to `infer_opaque_definition_from_instantiation`.
     #[instrument(skip(self, infcx))]
-    pub(in crate::borrow_check) fn infer_opaque_types(
+    pub(crate) fn infer_opaque_types(
         &self,
         infcx: &InferCtxt<'_, 'tcx>,
         opaque_ty_decls: VecMap<OpaqueTypeKey<'tcx>, Ty<'tcx>>,
@@ -105,7 +105,7 @@ impl<'tcx> RegionInferenceContext<'tcx> {
     /// that the regions produced are in fact equal to the named region they are
     /// replaced with. This is fine because this function is only to improve the
     /// region names in error messages.
-    pub(in crate::borrow_check) fn name_regions<T>(&self, tcx: TyCtxt<'tcx>, ty: T) -> T
+    pub(crate) fn name_regions<T>(&self, tcx: TyCtxt<'tcx>, ty: T) -> T
     where
         T: TypeFoldable<'tcx>,
     {
diff --git a/compiler/rustc_mir/src/borrow_check/region_infer/reverse_sccs.rs b/compiler/rustc_borrowck/src/region_infer/reverse_sccs.rs
similarity index 95%
rename from compiler/rustc_mir/src/borrow_check/region_infer/reverse_sccs.rs
rename to compiler/rustc_borrowck/src/region_infer/reverse_sccs.rs
index 5d345a6e63d6b..056907dcb1656 100644
--- a/compiler/rustc_mir/src/borrow_check/region_infer/reverse_sccs.rs
+++ b/compiler/rustc_borrowck/src/region_infer/reverse_sccs.rs
@@ -1,5 +1,5 @@
-use crate::borrow_check::constraints::ConstraintSccIndex;
-use crate::borrow_check::RegionInferenceContext;
+use crate::constraints::ConstraintSccIndex;
+use crate::RegionInferenceContext;
 use itertools::Itertools;
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_data_structures::graph::vec_graph::VecGraph;
diff --git a/compiler/rustc_mir/src/borrow_check/region_infer/values.rs b/compiler/rustc_borrowck/src/region_infer/values.rs
similarity index 100%
rename from compiler/rustc_mir/src/borrow_check/region_infer/values.rs
rename to compiler/rustc_borrowck/src/region_infer/values.rs
diff --git a/compiler/rustc_mir/src/borrow_check/renumber.rs b/compiler/rustc_borrowck/src/renumber.rs
similarity index 100%
rename from compiler/rustc_mir/src/borrow_check/renumber.rs
rename to compiler/rustc_borrowck/src/renumber.rs
diff --git a/compiler/rustc_mir/src/borrow_check/type_check/canonical.rs b/compiler/rustc_borrowck/src/type_check/canonical.rs
similarity index 98%
rename from compiler/rustc_mir/src/borrow_check/type_check/canonical.rs
rename to compiler/rustc_borrowck/src/type_check/canonical.rs
index b501716a89975..7a8c0a3da1f1f 100644
--- a/compiler/rustc_mir/src/borrow_check/type_check/canonical.rs
+++ b/compiler/rustc_borrowck/src/type_check/canonical.rs
@@ -8,7 +8,7 @@ use rustc_span::Span;
 use rustc_trait_selection::traits::query::type_op::{self, TypeOpOutput};
 use rustc_trait_selection::traits::query::Fallible;
 
-use crate::borrow_check::diagnostics::{ToUniverseInfo, UniverseInfo};
+use crate::diagnostics::{ToUniverseInfo, UniverseInfo};
 
 use super::{Locations, NormalizeLocation, TypeChecker};
 
diff --git a/compiler/rustc_mir/src/borrow_check/type_check/constraint_conversion.rs b/compiler/rustc_borrowck/src/type_check/constraint_conversion.rs
similarity index 99%
rename from compiler/rustc_mir/src/borrow_check/type_check/constraint_conversion.rs
rename to compiler/rustc_borrowck/src/type_check/constraint_conversion.rs
index 446a0f8e72fbd..b020746848535 100644
--- a/compiler/rustc_mir/src/borrow_check/type_check/constraint_conversion.rs
+++ b/compiler/rustc_borrowck/src/type_check/constraint_conversion.rs
@@ -9,7 +9,7 @@ use rustc_middle::ty::subst::GenericArgKind;
 use rustc_middle::ty::{self, TyCtxt};
 use rustc_span::DUMMY_SP;
 
-use crate::borrow_check::{
+use crate::{
     constraints::OutlivesConstraint,
     nll::ToRegionVid,
     region_infer::TypeTest,
diff --git a/compiler/rustc_mir/src/borrow_check/type_check/free_region_relations.rs b/compiler/rustc_borrowck/src/type_check/free_region_relations.rs
similarity index 99%
rename from compiler/rustc_mir/src/borrow_check/type_check/free_region_relations.rs
rename to compiler/rustc_borrowck/src/type_check/free_region_relations.rs
index 6426098d843fe..e1e8f6a61adb8 100644
--- a/compiler/rustc_mir/src/borrow_check/type_check/free_region_relations.rs
+++ b/compiler/rustc_borrowck/src/type_check/free_region_relations.rs
@@ -13,7 +13,7 @@ use rustc_trait_selection::traits::query::type_op::{self, TypeOp};
 use std::rc::Rc;
 use type_op::TypeOpOutput;
 
-use crate::borrow_check::{
+use crate::{
     nll::ToRegionVid,
     type_check::constraint_conversion,
     type_check::{Locations, MirTypeckRegionConstraints},
@@ -55,7 +55,7 @@ type RegionBoundPairs<'tcx> = Vec<(ty::Region<'tcx>, GenericKind<'tcx>)>;
 type NormalizedInputsAndOutput<'tcx> = Vec<Ty<'tcx>>;
 
 crate struct CreateResult<'tcx> {
-    pub(in crate::borrow_check) universal_region_relations: Frozen<UniversalRegionRelations<'tcx>>,
+    crate universal_region_relations: Frozen<UniversalRegionRelations<'tcx>>,
     crate region_bound_pairs: RegionBoundPairs<'tcx>,
     crate normalized_inputs_and_output: NormalizedInputsAndOutput<'tcx>,
 }
diff --git a/compiler/rustc_mir/src/borrow_check/type_check/input_output.rs b/compiler/rustc_borrowck/src/type_check/input_output.rs
similarity index 99%
rename from compiler/rustc_mir/src/borrow_check/type_check/input_output.rs
rename to compiler/rustc_borrowck/src/type_check/input_output.rs
index ba9b6926526be..9d6f6f60a94f9 100644
--- a/compiler/rustc_mir/src/borrow_check/type_check/input_output.rs
+++ b/compiler/rustc_borrowck/src/type_check/input_output.rs
@@ -7,16 +7,15 @@
 //! `RETURN_PLACE` the MIR arguments) are always fully normalized (and
 //! contain revealed `impl Trait` values).
 
+use rustc_index::vec::Idx;
 use rustc_infer::infer::LateBoundRegionConversionTime;
 use rustc_middle::mir::*;
 use rustc_middle::traits::ObligationCause;
 use rustc_middle::ty::{self, Ty};
-use rustc_trait_selection::traits::query::normalize::AtExt;
-
-use rustc_index::vec::Idx;
 use rustc_span::Span;
+use rustc_trait_selection::traits::query::normalize::AtExt;
 
-use crate::borrow_check::universal_regions::UniversalRegions;
+use crate::universal_regions::UniversalRegions;
 
 use super::{Locations, TypeChecker};
 
diff --git a/compiler/rustc_mir/src/borrow_check/type_check/liveness/local_use_map.rs b/compiler/rustc_borrowck/src/type_check/liveness/local_use_map.rs
similarity index 97%
rename from compiler/rustc_mir/src/borrow_check/type_check/liveness/local_use_map.rs
rename to compiler/rustc_borrowck/src/type_check/liveness/local_use_map.rs
index 7e8a33efe114e..8b74abd94c077 100644
--- a/compiler/rustc_mir/src/borrow_check/type_check/liveness/local_use_map.rs
+++ b/compiler/rustc_borrowck/src/type_check/liveness/local_use_map.rs
@@ -3,8 +3,8 @@ use rustc_index::vec::IndexVec;
 use rustc_middle::mir::visit::{PlaceContext, Visitor};
 use rustc_middle::mir::{Body, Local, Location};
 
-use crate::borrow_check::def_use::{self, DefUse};
-use crate::borrow_check::region_infer::values::{PointIndex, RegionValueElements};
+use crate::def_use::{self, DefUse};
+use crate::region_infer::values::{PointIndex, RegionValueElements};
 
 /// A map that cross references each local with the locations where it
 /// is defined (assigned), used, or dropped. Used during liveness
diff --git a/compiler/rustc_mir/src/borrow_check/type_check/liveness/mod.rs b/compiler/rustc_borrowck/src/type_check/liveness/mod.rs
similarity index 96%
rename from compiler/rustc_mir/src/borrow_check/type_check/liveness/mod.rs
rename to compiler/rustc_borrowck/src/type_check/liveness/mod.rs
index a34ae281b70df..1e712354d6a83 100644
--- a/compiler/rustc_mir/src/borrow_check/type_check/liveness/mod.rs
+++ b/compiler/rustc_borrowck/src/type_check/liveness/mod.rs
@@ -3,11 +3,11 @@ use rustc_middle::mir::{Body, Local};
 use rustc_middle::ty::{RegionVid, TyCtxt};
 use std::rc::Rc;
 
-use crate::dataflow::impls::MaybeInitializedPlaces;
-use crate::dataflow::move_paths::MoveData;
-use crate::dataflow::ResultsCursor;
+use rustc_mir_dataflow::impls::MaybeInitializedPlaces;
+use rustc_mir_dataflow::move_paths::MoveData;
+use rustc_mir_dataflow::ResultsCursor;
 
-use crate::borrow_check::{
+use crate::{
     constraints::OutlivesConstraintSet,
     facts::{AllFacts, AllFactsExt},
     location::LocationTable,
diff --git a/compiler/rustc_mir/src/borrow_check/type_check/liveness/polonius.rs b/compiler/rustc_borrowck/src/type_check/liveness/polonius.rs
similarity index 96%
rename from compiler/rustc_mir/src/borrow_check/type_check/liveness/polonius.rs
rename to compiler/rustc_borrowck/src/type_check/liveness/polonius.rs
index d285098c52ad2..79ab8b713f95d 100644
--- a/compiler/rustc_mir/src/borrow_check/type_check/liveness/polonius.rs
+++ b/compiler/rustc_borrowck/src/type_check/liveness/polonius.rs
@@ -1,10 +1,9 @@
-use crate::borrow_check::def_use::{self, DefUse};
-use crate::borrow_check::location::{LocationIndex, LocationTable};
-use crate::dataflow::indexes::MovePathIndex;
-use crate::dataflow::move_paths::{LookupResult, MoveData};
+use crate::def_use::{self, DefUse};
+use crate::location::{LocationIndex, LocationTable};
 use rustc_middle::mir::visit::{MutatingUseContext, PlaceContext, Visitor};
 use rustc_middle::mir::{Body, Local, Location, Place};
 use rustc_middle::ty::subst::GenericArg;
+use rustc_mir_dataflow::move_paths::{LookupResult, MoveData, MovePathIndex};
 
 use super::TypeChecker;
 
diff --git a/compiler/rustc_mir/src/borrow_check/type_check/liveness/trace.rs b/compiler/rustc_borrowck/src/type_check/liveness/trace.rs
similarity index 98%
rename from compiler/rustc_mir/src/borrow_check/type_check/liveness/trace.rs
rename to compiler/rustc_borrowck/src/type_check/liveness/trace.rs
index 566c11811e6e1..1671c7c627e19 100644
--- a/compiler/rustc_mir/src/borrow_check/type_check/liveness/trace.rs
+++ b/compiler/rustc_borrowck/src/type_check/liveness/trace.rs
@@ -8,12 +8,11 @@ use rustc_trait_selection::traits::query::type_op::outlives::DropckOutlives;
 use rustc_trait_selection::traits::query::type_op::{TypeOp, TypeOpOutput};
 use std::rc::Rc;
 
-use crate::dataflow::impls::MaybeInitializedPlaces;
-use crate::dataflow::indexes::MovePathIndex;
-use crate::dataflow::move_paths::{HasMoveData, MoveData};
-use crate::dataflow::ResultsCursor;
+use rustc_mir_dataflow::impls::MaybeInitializedPlaces;
+use rustc_mir_dataflow::move_paths::{HasMoveData, MoveData, MovePathIndex};
+use rustc_mir_dataflow::ResultsCursor;
 
-use crate::borrow_check::{
+use crate::{
     region_infer::values::{self, PointIndex, RegionValueElements},
     type_check::liveness::local_use_map::LocalUseMap,
     type_check::liveness::polonius,
diff --git a/compiler/rustc_mir/src/borrow_check/type_check/mod.rs b/compiler/rustc_borrowck/src/type_check/mod.rs
similarity index 99%
rename from compiler/rustc_mir/src/borrow_check/type_check/mod.rs
rename to compiler/rustc_borrowck/src/type_check/mod.rs
index 639bcb8fa94ef..2c8ff45b00da4 100644
--- a/compiler/rustc_mir/src/borrow_check/type_check/mod.rs
+++ b/compiler/rustc_borrowck/src/type_check/mod.rs
@@ -41,14 +41,14 @@ use rustc_trait_selection::traits::query::type_op::custom::CustomTypeOp;
 use rustc_trait_selection::traits::query::Fallible;
 use rustc_trait_selection::traits::{self, ObligationCause, PredicateObligations};
 
-use crate::dataflow::impls::MaybeInitializedPlaces;
-use crate::dataflow::move_paths::MoveData;
-use crate::dataflow::ResultsCursor;
-use crate::transform::{
+use rustc_const_eval::transform::{
     check_consts::ConstCx, promote_consts::is_const_fn_in_array_repeat_expression,
 };
+use rustc_mir_dataflow::impls::MaybeInitializedPlaces;
+use rustc_mir_dataflow::move_paths::MoveData;
+use rustc_mir_dataflow::ResultsCursor;
 
-use crate::borrow_check::{
+use crate::{
     borrow_set::BorrowSet,
     constraints::{OutlivesConstraint, OutlivesConstraintSet},
     diagnostics::UniverseInfo,
@@ -68,7 +68,7 @@ use crate::borrow_check::{
 
 macro_rules! span_mirbug {
     ($context:expr, $elem:expr, $($message:tt)*) => ({
-        $crate::borrow_check::type_check::mirbug(
+        $crate::type_check::mirbug(
             $context.tcx(),
             $context.last_span,
             &format!(
@@ -887,7 +887,7 @@ struct BorrowCheckContext<'a, 'tcx> {
 
 crate struct MirTypeckResults<'tcx> {
     crate constraints: MirTypeckRegionConstraints<'tcx>,
-    pub(in crate::borrow_check) universal_region_relations: Frozen<UniversalRegionRelations<'tcx>>,
+    crate universal_region_relations: Frozen<UniversalRegionRelations<'tcx>>,
     crate opaque_type_values: VecMap<OpaqueTypeKey<'tcx>, Ty<'tcx>>,
 }
 
diff --git a/compiler/rustc_mir/src/borrow_check/type_check/relate_tys.rs b/compiler/rustc_borrowck/src/type_check/relate_tys.rs
similarity index 96%
rename from compiler/rustc_mir/src/borrow_check/type_check/relate_tys.rs
rename to compiler/rustc_borrowck/src/type_check/relate_tys.rs
index 971c4daa6b311..0b9c33ccb775a 100644
--- a/compiler/rustc_mir/src/borrow_check/type_check/relate_tys.rs
+++ b/compiler/rustc_borrowck/src/type_check/relate_tys.rs
@@ -5,9 +5,9 @@ use rustc_middle::ty::relate::TypeRelation;
 use rustc_middle::ty::{self, Const, Ty};
 use rustc_trait_selection::traits::query::Fallible;
 
-use crate::borrow_check::constraints::OutlivesConstraint;
-use crate::borrow_check::diagnostics::UniverseInfo;
-use crate::borrow_check::type_check::{BorrowCheckContext, Locations};
+use crate::constraints::OutlivesConstraint;
+use crate::diagnostics::UniverseInfo;
+use crate::type_check::{BorrowCheckContext, Locations};
 
 /// Adds sufficient constraints to ensure that `a R b` where `R` depends on `v`:
 ///
diff --git a/compiler/rustc_mir/src/borrow_check/universal_regions.rs b/compiler/rustc_borrowck/src/universal_regions.rs
similarity index 99%
rename from compiler/rustc_mir/src/borrow_check/universal_regions.rs
rename to compiler/rustc_borrowck/src/universal_regions.rs
index 3c9b4272b3649..bebd19370299d 100644
--- a/compiler/rustc_mir/src/borrow_check/universal_regions.rs
+++ b/compiler/rustc_borrowck/src/universal_regions.rs
@@ -26,7 +26,7 @@ use rustc_middle::ty::subst::{InternalSubsts, Subst, SubstsRef};
 use rustc_middle::ty::{self, RegionVid, Ty, TyCtxt};
 use std::iter;
 
-use crate::borrow_check::nll::ToRegionVid;
+use crate::nll::ToRegionVid;
 
 #[derive(Debug)]
 pub struct UniversalRegions<'tcx> {
diff --git a/compiler/rustc_mir/src/borrow_check/used_muts.rs b/compiler/rustc_borrowck/src/used_muts.rs
similarity index 99%
rename from compiler/rustc_mir/src/borrow_check/used_muts.rs
rename to compiler/rustc_borrowck/src/used_muts.rs
index e027056842db9..6022a9809502b 100644
--- a/compiler/rustc_mir/src/borrow_check/used_muts.rs
+++ b/compiler/rustc_borrowck/src/used_muts.rs
@@ -1,11 +1,10 @@
+use rustc_data_structures::fx::FxHashSet;
 use rustc_middle::mir::visit::{PlaceContext, Visitor};
 use rustc_middle::mir::{
     Local, Location, Place, Statement, StatementKind, Terminator, TerminatorKind,
 };
 
-use rustc_data_structures::fx::FxHashSet;
-
-use crate::borrow_check::MirBorrowckCtxt;
+use crate::MirBorrowckCtxt;
 
 impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
     /// Walks the MIR adding to the set of `used_mut` locals that will be ignored for the purposes
diff --git a/compiler/rustc_codegen_cranelift/scripts/filter_profile.rs b/compiler/rustc_codegen_cranelift/scripts/filter_profile.rs
index c4801a0a87b88..7a51293f5cda5 100755
--- a/compiler/rustc_codegen_cranelift/scripts/filter_profile.rs
+++ b/compiler/rustc_codegen_cranelift/scripts/filter_profile.rs
@@ -42,7 +42,7 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
             continue;
         }
 
-        if stack.contains("rustc_mir::monomorphize::partitioning::collect_and_partition_mono_items")
+        if stack.contains("rustc_monomorphize::partitioning::collect_and_partition_mono_items")
             || stack.contains("rustc_incremental::assert_dep_graph::assert_dep_graph")
             || stack.contains("rustc_symbol_mangling::test::report_symbol_names")
         {
@@ -81,7 +81,7 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
         }
 
         const COLLECT_AND_PARTITION_MONO_ITEMS: &str =
-            "rustc_mir::monomorphize::partitioning::collect_and_partition_mono_items";
+            "rustc_monomorphize::partitioning::collect_and_partition_mono_items";
         if let Some(index) = stack.find(COLLECT_AND_PARTITION_MONO_ITEMS) {
             stack = &stack[..index + COLLECT_AND_PARTITION_MONO_ITEMS.len()];
         }
diff --git a/compiler/rustc_codegen_cranelift/src/base.rs b/compiler/rustc_codegen_cranelift/src/base.rs
index e99a227a3a6ea..46a7485e4ef9c 100644
--- a/compiler/rustc_codegen_cranelift/src/base.rs
+++ b/compiler/rustc_codegen_cranelift/src/base.rs
@@ -23,7 +23,7 @@ pub(crate) fn codegen_fn<'tcx>(
     let mir = tcx.instance_mir(instance.def);
     let _mir_guard = crate::PrintOnPanic(|| {
         let mut buf = Vec::new();
-        rustc_mir::util::write_mir_pretty(tcx, Some(instance.def_id()), &mut buf).unwrap();
+        rustc_middle::mir::write_mir_pretty(tcx, Some(instance.def_id()), &mut buf).unwrap();
         String::from_utf8_lossy(&buf).into_owned()
     });
 
diff --git a/compiler/rustc_codegen_cranelift/src/lib.rs b/compiler/rustc_codegen_cranelift/src/lib.rs
index 2e5e8f683cdaa..87193e3ef5341 100644
--- a/compiler/rustc_codegen_cranelift/src/lib.rs
+++ b/compiler/rustc_codegen_cranelift/src/lib.rs
@@ -16,7 +16,6 @@ extern crate rustc_incremental;
 extern crate rustc_index;
 extern crate rustc_interface;
 extern crate rustc_metadata;
-extern crate rustc_mir;
 extern crate rustc_session;
 extern crate rustc_span;
 extern crate rustc_target;
diff --git a/compiler/rustc_const_eval/Cargo.toml b/compiler/rustc_const_eval/Cargo.toml
new file mode 100644
index 0000000000000..1653d5cf6c560
--- /dev/null
+++ b/compiler/rustc_const_eval/Cargo.toml
@@ -0,0 +1,27 @@
+[package]
+name = "rustc_const_eval"
+version = "0.0.0"
+edition = "2018"
+
+[lib]
+doctest = false
+
+[dependencies]
+either = "1.5.0"
+gsgdt = "0.1.2"
+tracing = "0.1"
+rustc_apfloat = { path = "../rustc_apfloat" }
+rustc_ast = { path = "../rustc_ast" }
+rustc_attr = { path = "../rustc_attr" }
+rustc_data_structures = { path = "../rustc_data_structures" }
+rustc_errors = { path = "../rustc_errors" }
+rustc_hir = { path = "../rustc_hir" }
+rustc_index = { path = "../rustc_index" }
+rustc_infer = { path = "../rustc_infer" }
+rustc_macros = { path = "../rustc_macros" }
+rustc_middle = { path = "../rustc_middle" }
+rustc_mir_dataflow = { path = "../rustc_mir_dataflow" }
+rustc_session = { path = "../rustc_session" }
+rustc_target = { path = "../rustc_target" }
+rustc_trait_selection = { path = "../rustc_trait_selection" }
+rustc_span = { path = "../rustc_span" }
diff --git a/compiler/rustc_mir/src/const_eval/error.rs b/compiler/rustc_const_eval/src/const_eval/error.rs
similarity index 100%
rename from compiler/rustc_mir/src/const_eval/error.rs
rename to compiler/rustc_const_eval/src/const_eval/error.rs
diff --git a/compiler/rustc_mir/src/const_eval/eval_queries.rs b/compiler/rustc_const_eval/src/const_eval/eval_queries.rs
similarity index 99%
rename from compiler/rustc_mir/src/const_eval/eval_queries.rs
rename to compiler/rustc_const_eval/src/const_eval/eval_queries.rs
index 3e8a93e08c29d..171fc45ea4696 100644
--- a/compiler/rustc_mir/src/const_eval/eval_queries.rs
+++ b/compiler/rustc_const_eval/src/const_eval/eval_queries.rs
@@ -5,12 +5,12 @@ use crate::interpret::{
     Immediate, InternKind, InterpCx, InterpResult, MPlaceTy, MemoryKind, OpTy, RefTracking, Scalar,
     ScalarMaybeUninit, StackPopCleanup,
 };
-use crate::util::pretty::display_allocation;
 
 use rustc_errors::ErrorReported;
 use rustc_hir::def::DefKind;
 use rustc_middle::mir;
 use rustc_middle::mir::interpret::ErrorHandled;
+use rustc_middle::mir::pretty::display_allocation;
 use rustc_middle::traits::Reveal;
 use rustc_middle::ty::layout::LayoutOf;
 use rustc_middle::ty::print::with_no_trimmed_paths;
diff --git a/compiler/rustc_mir/src/const_eval/fn_queries.rs b/compiler/rustc_const_eval/src/const_eval/fn_queries.rs
similarity index 100%
rename from compiler/rustc_mir/src/const_eval/fn_queries.rs
rename to compiler/rustc_const_eval/src/const_eval/fn_queries.rs
diff --git a/compiler/rustc_mir/src/const_eval/machine.rs b/compiler/rustc_const_eval/src/const_eval/machine.rs
similarity index 100%
rename from compiler/rustc_mir/src/const_eval/machine.rs
rename to compiler/rustc_const_eval/src/const_eval/machine.rs
diff --git a/compiler/rustc_mir/src/const_eval/mod.rs b/compiler/rustc_const_eval/src/const_eval/mod.rs
similarity index 100%
rename from compiler/rustc_mir/src/const_eval/mod.rs
rename to compiler/rustc_const_eval/src/const_eval/mod.rs
diff --git a/compiler/rustc_mir/src/interpret/cast.rs b/compiler/rustc_const_eval/src/interpret/cast.rs
similarity index 100%
rename from compiler/rustc_mir/src/interpret/cast.rs
rename to compiler/rustc_const_eval/src/interpret/cast.rs
diff --git a/compiler/rustc_mir/src/interpret/eval_context.rs b/compiler/rustc_const_eval/src/interpret/eval_context.rs
similarity index 99%
rename from compiler/rustc_mir/src/interpret/eval_context.rs
rename to compiler/rustc_const_eval/src/interpret/eval_context.rs
index 05502d8b21f1c..0521443533b78 100644
--- a/compiler/rustc_mir/src/interpret/eval_context.rs
+++ b/compiler/rustc_const_eval/src/interpret/eval_context.rs
@@ -12,6 +12,7 @@ use rustc_middle::ty::layout::{self, LayoutError, LayoutOf, LayoutOfHelpers, TyA
 use rustc_middle::ty::{
     self, query::TyCtxtAt, subst::SubstsRef, ParamEnv, Ty, TyCtxt, TypeFoldable,
 };
+use rustc_mir_dataflow::storage::AlwaysLiveLocals;
 use rustc_session::Limit;
 use rustc_span::{Pos, Span};
 use rustc_target::abi::{Align, HasDataLayout, Size, TargetDataLayout};
@@ -22,7 +23,6 @@ use super::{
     ScalarMaybeUninit, StackPopJump,
 };
 use crate::transform::validate::equal_up_to_regions;
-use crate::util::storage::AlwaysLiveLocals;
 
 pub struct InterpCx<'mir, 'tcx, M: Machine<'mir, 'tcx>> {
     /// Stores the `Machine` instance.
diff --git a/compiler/rustc_mir/src/interpret/intern.rs b/compiler/rustc_const_eval/src/interpret/intern.rs
similarity index 99%
rename from compiler/rustc_mir/src/interpret/intern.rs
rename to compiler/rustc_const_eval/src/interpret/intern.rs
index f2457d11d9ee3..84e79408397e5 100644
--- a/compiler/rustc_mir/src/interpret/intern.rs
+++ b/compiler/rustc_const_eval/src/interpret/intern.rs
@@ -420,7 +420,7 @@ impl<'mir, 'tcx: 'mir, M: super::intern::CompileTimeMachine<'mir, 'tcx, !>>
     /// A helper function that allocates memory for the layout given and gives you access to mutate
     /// it. Once your own mutation code is done, the backing `Allocation` is removed from the
     /// current `Memory` and returned.
-    pub(crate) fn intern_with_temp_alloc(
+    pub fn intern_with_temp_alloc(
         &mut self,
         layout: TyAndLayout<'tcx>,
         f: impl FnOnce(
diff --git a/compiler/rustc_mir/src/interpret/intrinsics.rs b/compiler/rustc_const_eval/src/interpret/intrinsics.rs
similarity index 100%
rename from compiler/rustc_mir/src/interpret/intrinsics.rs
rename to compiler/rustc_const_eval/src/interpret/intrinsics.rs
diff --git a/compiler/rustc_mir/src/interpret/intrinsics/caller_location.rs b/compiler/rustc_const_eval/src/interpret/intrinsics/caller_location.rs
similarity index 100%
rename from compiler/rustc_mir/src/interpret/intrinsics/caller_location.rs
rename to compiler/rustc_const_eval/src/interpret/intrinsics/caller_location.rs
diff --git a/compiler/rustc_mir/src/interpret/intrinsics/type_name.rs b/compiler/rustc_const_eval/src/interpret/intrinsics/type_name.rs
similarity index 100%
rename from compiler/rustc_mir/src/interpret/intrinsics/type_name.rs
rename to compiler/rustc_const_eval/src/interpret/intrinsics/type_name.rs
diff --git a/compiler/rustc_mir/src/interpret/machine.rs b/compiler/rustc_const_eval/src/interpret/machine.rs
similarity index 100%
rename from compiler/rustc_mir/src/interpret/machine.rs
rename to compiler/rustc_const_eval/src/interpret/machine.rs
diff --git a/compiler/rustc_mir/src/interpret/memory.rs b/compiler/rustc_const_eval/src/interpret/memory.rs
similarity index 99%
rename from compiler/rustc_mir/src/interpret/memory.rs
rename to compiler/rustc_const_eval/src/interpret/memory.rs
index 4d13274a1200d..b8b6ff93753f0 100644
--- a/compiler/rustc_mir/src/interpret/memory.rs
+++ b/compiler/rustc_const_eval/src/interpret/memory.rs
@@ -15,6 +15,7 @@ use std::ptr;
 
 use rustc_ast::Mutability;
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
+use rustc_middle::mir::display_allocation;
 use rustc_middle::ty::{Instance, ParamEnv, TyCtxt};
 use rustc_target::abi::{Align, HasDataLayout, Size, TargetDataLayout};
 
@@ -23,7 +24,6 @@ use super::{
     InterpResult, Machine, MayLeak, Pointer, PointerArithmetic, Provenance, Scalar,
     ScalarMaybeUninit,
 };
-use crate::util::pretty;
 
 #[derive(Debug, PartialEq, Copy, Clone)]
 pub enum MemoryKind<T> {
@@ -851,7 +851,7 @@ impl<'a, 'mir, 'tcx, M: Machine<'mir, 'tcx>> std::fmt::Debug for DumpAllocs<'a,
             for alloc_id in alloc.relocations().values().map(|tag| tag.get_alloc_id()) {
                 allocs_to_print.push_back(alloc_id);
             }
-            write!(fmt, "{}", pretty::display_allocation(tcx, alloc))
+            write!(fmt, "{}", display_allocation(tcx, alloc))
         }
 
         let mut allocs_to_print: VecDeque<_> = self.allocs.iter().copied().collect();
diff --git a/compiler/rustc_mir/src/interpret/mod.rs b/compiler/rustc_const_eval/src/interpret/mod.rs
similarity index 100%
rename from compiler/rustc_mir/src/interpret/mod.rs
rename to compiler/rustc_const_eval/src/interpret/mod.rs
diff --git a/compiler/rustc_mir/src/interpret/operand.rs b/compiler/rustc_const_eval/src/interpret/operand.rs
similarity index 99%
rename from compiler/rustc_mir/src/interpret/operand.rs
rename to compiler/rustc_const_eval/src/interpret/operand.rs
index e67a6690836ad..63aca67c9443c 100644
--- a/compiler/rustc_mir/src/interpret/operand.rs
+++ b/compiler/rustc_const_eval/src/interpret/operand.rs
@@ -296,7 +296,7 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
     /// Note that for a given layout, this operation will either always fail or always
     /// succeed!  Whether it succeeds depends on whether the layout can be represented
     /// in an `Immediate`, not on which data is stored there currently.
-    pub(crate) fn try_read_immediate(
+    pub fn try_read_immediate(
         &self,
         src: &OpTy<'tcx, M::PointerTag>,
     ) -> InterpResult<'tcx, Result<ImmTy<'tcx, M::PointerTag>, MPlaceTy<'tcx, M::PointerTag>>> {
@@ -547,7 +547,7 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
     // in patterns via the `const_eval` module
     /// The `val` and `layout` are assumed to already be in our interpreter
     /// "universe" (param_env).
-    crate fn const_to_op(
+    pub fn const_to_op(
         &self,
         val: &ty::Const<'tcx>,
         layout: Option<TyAndLayout<'tcx>>,
@@ -566,7 +566,7 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
         }
     }
 
-    crate fn mir_const_to_op(
+    pub fn mir_const_to_op(
         &self,
         val: &mir::ConstantKind<'tcx>,
         layout: Option<TyAndLayout<'tcx>>,
diff --git a/compiler/rustc_mir/src/interpret/operator.rs b/compiler/rustc_const_eval/src/interpret/operator.rs
similarity index 100%
rename from compiler/rustc_mir/src/interpret/operator.rs
rename to compiler/rustc_const_eval/src/interpret/operator.rs
diff --git a/compiler/rustc_mir/src/interpret/place.rs b/compiler/rustc_const_eval/src/interpret/place.rs
similarity index 100%
rename from compiler/rustc_mir/src/interpret/place.rs
rename to compiler/rustc_const_eval/src/interpret/place.rs
diff --git a/compiler/rustc_mir/src/interpret/step.rs b/compiler/rustc_const_eval/src/interpret/step.rs
similarity index 99%
rename from compiler/rustc_mir/src/interpret/step.rs
rename to compiler/rustc_const_eval/src/interpret/step.rs
index 1e96581c392d2..09bd07660a33e 100644
--- a/compiler/rustc_mir/src/interpret/step.rs
+++ b/compiler/rustc_const_eval/src/interpret/step.rs
@@ -76,7 +76,7 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
 
     /// Runs the interpretation logic for the given `mir::Statement` at the current frame and
     /// statement counter. This also moves the statement counter forward.
-    crate fn statement(&mut self, stmt: &mir::Statement<'tcx>) -> InterpResult<'tcx> {
+    pub fn statement(&mut self, stmt: &mir::Statement<'tcx>) -> InterpResult<'tcx> {
         info!("{:?}", stmt);
 
         use rustc_middle::mir::StatementKind::*;
diff --git a/compiler/rustc_mir/src/interpret/terminator.rs b/compiler/rustc_const_eval/src/interpret/terminator.rs
similarity index 100%
rename from compiler/rustc_mir/src/interpret/terminator.rs
rename to compiler/rustc_const_eval/src/interpret/terminator.rs
diff --git a/compiler/rustc_mir/src/interpret/traits.rs b/compiler/rustc_const_eval/src/interpret/traits.rs
similarity index 100%
rename from compiler/rustc_mir/src/interpret/traits.rs
rename to compiler/rustc_const_eval/src/interpret/traits.rs
diff --git a/compiler/rustc_mir/src/interpret/util.rs b/compiler/rustc_const_eval/src/interpret/util.rs
similarity index 100%
rename from compiler/rustc_mir/src/interpret/util.rs
rename to compiler/rustc_const_eval/src/interpret/util.rs
diff --git a/compiler/rustc_mir/src/interpret/validity.rs b/compiler/rustc_const_eval/src/interpret/validity.rs
similarity index 100%
rename from compiler/rustc_mir/src/interpret/validity.rs
rename to compiler/rustc_const_eval/src/interpret/validity.rs
diff --git a/compiler/rustc_mir/src/interpret/visitor.rs b/compiler/rustc_const_eval/src/interpret/visitor.rs
similarity index 100%
rename from compiler/rustc_mir/src/interpret/visitor.rs
rename to compiler/rustc_const_eval/src/interpret/visitor.rs
diff --git a/compiler/rustc_mir/src/lib.rs b/compiler/rustc_const_eval/src/lib.rs
similarity index 68%
rename from compiler/rustc_mir/src/lib.rs
rename to compiler/rustc_const_eval/src/lib.rs
index e439a247c7f6c..0aa2dfb010f54 100644
--- a/compiler/rustc_mir/src/lib.rs
+++ b/compiler/rustc_const_eval/src/lib.rs
@@ -4,32 +4,25 @@ Rust MIR: a lowered representation of Rust.
 
 */
 
-#![feature(nll)]
-#![feature(in_band_lifetimes)]
-#![feature(array_windows)]
 #![feature(assert_matches)]
 #![cfg_attr(bootstrap, feature(bindings_after_at))]
 #![feature(bool_to_option)]
 #![feature(box_patterns)]
+#![feature(control_flow_enum)]
 #![feature(crate_visibility_modifier)]
 #![feature(decl_macro)]
 #![feature(exact_size_is_empty)]
-#![feature(format_args_capture)]
+#![feature(in_band_lifetimes)]
 #![feature(iter_zip)]
-#![feature(never_type)]
 #![feature(map_try_insert)]
 #![feature(min_specialization)]
 #![feature(slice_ptr_get)]
+#![feature(option_get_or_insert_default)]
+#![feature(never_type)]
+#![feature(trait_alias)]
 #![feature(trusted_len)]
+#![feature(trusted_step)]
 #![feature(try_blocks)]
-#![feature(associated_type_defaults)]
-#![feature(stmt_expr_attributes)]
-#![feature(trait_alias)]
-#![feature(option_get_or_insert_default)]
-#![feature(once_cell)]
-#![feature(control_flow_enum)]
-#![feature(try_reserve)]
-#![feature(try_reserve_kind)]
 #![recursion_limit = "256"]
 
 #[macro_use]
@@ -37,32 +30,18 @@ extern crate tracing;
 #[macro_use]
 extern crate rustc_middle;
 
-mod borrow_check;
 pub mod const_eval;
-pub mod dataflow;
 pub mod interpret;
-pub mod monomorphize;
-mod shim;
 pub mod transform;
 pub mod util;
 
-// A public API provided for the Rust compiler consumers.
-pub use self::borrow_check::consumers;
-
 use rustc_middle::ty::query::Providers;
 
 pub fn provide(providers: &mut Providers) {
-    borrow_check::provide(providers);
     const_eval::provide(providers);
-    shim::provide(providers);
-    transform::provide(providers);
-    monomorphize::partitioning::provide(providers);
-    monomorphize::polymorphize::provide(providers);
     providers.eval_to_const_value_raw = const_eval::eval_to_const_value_raw_provider;
     providers.eval_to_allocation_raw = const_eval::eval_to_allocation_raw_provider;
     providers.const_caller_location = const_eval::const_caller_location;
-    providers.mir_callgraph_reachable = transform::inline::cycle::mir_callgraph_reachable;
-    providers.mir_inliner_callees = transform::inline::cycle::mir_inliner_callees;
     providers.destructure_const = |tcx, param_env_and_value| {
         let (param_env, value) = param_env_and_value.into_parts();
         const_eval::destructure_const(tcx, param_env, value)
diff --git a/compiler/rustc_mir/src/transform/check_consts/check.rs b/compiler/rustc_const_eval/src/transform/check_consts/check.rs
similarity index 99%
rename from compiler/rustc_mir/src/transform/check_consts/check.rs
rename to compiler/rustc_const_eval/src/transform/check_consts/check.rs
index 0c38127682359..d02b4286c175a 100644
--- a/compiler/rustc_mir/src/transform/check_consts/check.rs
+++ b/compiler/rustc_const_eval/src/transform/check_consts/check.rs
@@ -12,6 +12,8 @@ use rustc_middle::ty::cast::CastTy;
 use rustc_middle::ty::subst::{GenericArgKind, InternalSubsts};
 use rustc_middle::ty::{self, adjustment::PointerCast, Instance, InstanceDef, Ty, TyCtxt};
 use rustc_middle::ty::{Binder, TraitPredicate, TraitRef};
+use rustc_mir_dataflow::impls::MaybeMutBorrowedLocals;
+use rustc_mir_dataflow::{self, Analysis};
 use rustc_span::{sym, Span, Symbol};
 use rustc_trait_selection::traits::error_reporting::InferCtxtExt;
 use rustc_trait_selection::traits::{self, SelectionContext, TraitEngine};
@@ -24,17 +26,15 @@ use super::qualifs::{self, CustomEq, HasMutInterior, NeedsDrop};
 use super::resolver::FlowSensitiveAnalysis;
 use super::{is_lang_panic_fn, ConstCx, Qualif};
 use crate::const_eval::is_unstable_const_fn;
-use crate::dataflow::impls::MaybeMutBorrowedLocals;
-use crate::dataflow::{self, Analysis};
 
 // We are using `MaybeMutBorrowedLocals` as a proxy for whether an item may have been mutated
 // through a pointer prior to the given point. This is okay even though `MaybeMutBorrowedLocals`
 // kills locals upon `StorageDead` because a local will never be used after a `StorageDead`.
 type IndirectlyMutableResults<'mir, 'tcx> =
-    dataflow::ResultsCursor<'mir, 'tcx, MaybeMutBorrowedLocals<'mir, 'tcx>>;
+    rustc_mir_dataflow::ResultsCursor<'mir, 'tcx, MaybeMutBorrowedLocals<'mir, 'tcx>>;
 
 type QualifResults<'mir, 'tcx, Q> =
-    dataflow::ResultsCursor<'mir, 'tcx, FlowSensitiveAnalysis<'mir, 'mir, 'tcx, Q>>;
+    rustc_mir_dataflow::ResultsCursor<'mir, 'tcx, FlowSensitiveAnalysis<'mir, 'mir, 'tcx, Q>>;
 
 #[derive(Default)]
 pub struct Qualifs<'mir, 'tcx> {
diff --git a/compiler/rustc_mir/src/transform/check_consts/mod.rs b/compiler/rustc_const_eval/src/transform/check_consts/mod.rs
similarity index 100%
rename from compiler/rustc_mir/src/transform/check_consts/mod.rs
rename to compiler/rustc_const_eval/src/transform/check_consts/mod.rs
diff --git a/compiler/rustc_mir/src/transform/check_consts/ops.rs b/compiler/rustc_const_eval/src/transform/check_consts/ops.rs
similarity index 100%
rename from compiler/rustc_mir/src/transform/check_consts/ops.rs
rename to compiler/rustc_const_eval/src/transform/check_consts/ops.rs
diff --git a/compiler/rustc_mir/src/transform/check_consts/post_drop_elaboration.rs b/compiler/rustc_const_eval/src/transform/check_consts/post_drop_elaboration.rs
similarity index 100%
rename from compiler/rustc_mir/src/transform/check_consts/post_drop_elaboration.rs
rename to compiler/rustc_const_eval/src/transform/check_consts/post_drop_elaboration.rs
diff --git a/compiler/rustc_mir/src/transform/check_consts/qualifs.rs b/compiler/rustc_const_eval/src/transform/check_consts/qualifs.rs
similarity index 100%
rename from compiler/rustc_mir/src/transform/check_consts/qualifs.rs
rename to compiler/rustc_const_eval/src/transform/check_consts/qualifs.rs
diff --git a/compiler/rustc_mir/src/transform/check_consts/resolver.rs b/compiler/rustc_const_eval/src/transform/check_consts/resolver.rs
similarity index 97%
rename from compiler/rustc_mir/src/transform/check_consts/resolver.rs
rename to compiler/rustc_const_eval/src/transform/check_consts/resolver.rs
index a00301952b328..8e1b69a1d7413 100644
--- a/compiler/rustc_mir/src/transform/check_consts/resolver.rs
+++ b/compiler/rustc_const_eval/src/transform/check_consts/resolver.rs
@@ -9,7 +9,6 @@ use rustc_middle::mir::{self, BasicBlock, Local, Location};
 use std::marker::PhantomData;
 
 use super::{qualifs, ConstCx, Qualif};
-use crate::dataflow;
 
 /// A `Visitor` that propagates qualifs between locals. This defines the transfer function of
 /// `FlowSensitiveAnalysis`.
@@ -165,7 +164,7 @@ where
     }
 }
 
-impl<Q> dataflow::AnalysisDomain<'tcx> for FlowSensitiveAnalysis<'_, '_, 'tcx, Q>
+impl<Q> rustc_mir_dataflow::AnalysisDomain<'tcx> for FlowSensitiveAnalysis<'_, '_, 'tcx, Q>
 where
     Q: Qualif,
 {
@@ -182,7 +181,7 @@ where
     }
 }
 
-impl<Q> dataflow::Analysis<'tcx> for FlowSensitiveAnalysis<'_, '_, 'tcx, Q>
+impl<Q> rustc_mir_dataflow::Analysis<'tcx> for FlowSensitiveAnalysis<'_, '_, 'tcx, Q>
 where
     Q: Qualif,
 {
diff --git a/compiler/rustc_const_eval/src/transform/mod.rs b/compiler/rustc_const_eval/src/transform/mod.rs
new file mode 100644
index 0000000000000..38c28f34934a4
--- /dev/null
+++ b/compiler/rustc_const_eval/src/transform/mod.rs
@@ -0,0 +1,5 @@
+pub mod check_consts;
+pub mod promote_consts;
+pub mod validate;
+
+pub use rustc_middle::mir::MirPass;
diff --git a/compiler/rustc_mir/src/transform/promote_consts.rs b/compiler/rustc_const_eval/src/transform/promote_consts.rs
similarity index 99%
rename from compiler/rustc_mir/src/transform/promote_consts.rs
rename to compiler/rustc_const_eval/src/transform/promote_consts.rs
index 1b43670ba3ac1..6822ad2d7b5dd 100644
--- a/compiler/rustc_mir/src/transform/promote_consts.rs
+++ b/compiler/rustc_const_eval/src/transform/promote_consts.rs
@@ -1058,7 +1058,7 @@ pub fn promote_candidates<'tcx>(
 
 /// This function returns `true` if the function being called in the array
 /// repeat expression is a `const` function.
-crate fn is_const_fn_in_array_repeat_expression<'tcx>(
+pub fn is_const_fn_in_array_repeat_expression<'tcx>(
     ccx: &ConstCx<'_, 'tcx>,
     place: &Place<'tcx>,
     body: &Body<'tcx>,
diff --git a/compiler/rustc_mir/src/transform/validate.rs b/compiler/rustc_const_eval/src/transform/validate.rs
similarity index 99%
rename from compiler/rustc_mir/src/transform/validate.rs
rename to compiler/rustc_const_eval/src/transform/validate.rs
index 835789069bb2e..40a32a76c9446 100644
--- a/compiler/rustc_mir/src/transform/validate.rs
+++ b/compiler/rustc_const_eval/src/transform/validate.rs
@@ -1,9 +1,5 @@
 //! Validates the MIR to ensure that invariants are upheld.
 
-use crate::dataflow::impls::MaybeStorageLive;
-use crate::dataflow::{Analysis, ResultsCursor};
-use crate::util::storage::AlwaysLiveLocals;
-
 use super::MirPass;
 use rustc_index::bit_set::BitSet;
 use rustc_infer::infer::TyCtxtInferExt;
@@ -17,6 +13,9 @@ use rustc_middle::mir::{
 };
 use rustc_middle::ty::fold::BottomUpFolder;
 use rustc_middle::ty::{self, ParamEnv, Ty, TyCtxt, TypeFoldable};
+use rustc_mir_dataflow::impls::MaybeStorageLive;
+use rustc_mir_dataflow::storage::AlwaysLiveLocals;
+use rustc_mir_dataflow::{Analysis, ResultsCursor};
 use rustc_target::abi::Size;
 
 #[derive(Copy, Clone, Debug)]
diff --git a/compiler/rustc_mir/src/util/aggregate.rs b/compiler/rustc_const_eval/src/util/aggregate.rs
similarity index 100%
rename from compiler/rustc_mir/src/util/aggregate.rs
rename to compiler/rustc_const_eval/src/util/aggregate.rs
diff --git a/compiler/rustc_mir/src/util/alignment.rs b/compiler/rustc_const_eval/src/util/alignment.rs
similarity index 100%
rename from compiler/rustc_mir/src/util/alignment.rs
rename to compiler/rustc_const_eval/src/util/alignment.rs
diff --git a/compiler/rustc_mir/src/util/collect_writes.rs b/compiler/rustc_const_eval/src/util/collect_writes.rs
similarity index 97%
rename from compiler/rustc_mir/src/util/collect_writes.rs
rename to compiler/rustc_const_eval/src/util/collect_writes.rs
index ecf3b08a96eed..9c56fd722bda6 100644
--- a/compiler/rustc_mir/src/util/collect_writes.rs
+++ b/compiler/rustc_const_eval/src/util/collect_writes.rs
@@ -2,7 +2,7 @@ use rustc_middle::mir::visit::PlaceContext;
 use rustc_middle::mir::visit::Visitor;
 use rustc_middle::mir::{Body, Local, Location};
 
-crate trait FindAssignments {
+pub trait FindAssignments {
     // Finds all statements that assign directly to local (i.e., X = ...)
     // and returns their locations.
     fn find_assignments(&self, local: Local) -> Vec<Location>;
diff --git a/compiler/rustc_mir/src/util/find_self_call.rs b/compiler/rustc_const_eval/src/util/find_self_call.rs
similarity index 100%
rename from compiler/rustc_mir/src/util/find_self_call.rs
rename to compiler/rustc_const_eval/src/util/find_self_call.rs
diff --git a/compiler/rustc_const_eval/src/util/mod.rs b/compiler/rustc_const_eval/src/util/mod.rs
new file mode 100644
index 0000000000000..4a406f8bfd088
--- /dev/null
+++ b/compiler/rustc_const_eval/src/util/mod.rs
@@ -0,0 +1,8 @@
+pub mod aggregate;
+mod alignment;
+pub mod collect_writes;
+mod find_self_call;
+
+pub use self::aggregate::expand_aggregate;
+pub use self::alignment::is_disaligned;
+pub use self::find_self_call::find_self_call;
diff --git a/compiler/rustc_driver/Cargo.toml b/compiler/rustc_driver/Cargo.toml
index 57159962a9e68..ba8616cc6ef73 100644
--- a/compiler/rustc_driver/Cargo.toml
+++ b/compiler/rustc_driver/Cargo.toml
@@ -22,7 +22,7 @@ rustc_feature = { path = "../rustc_feature" }
 rustc_hir = { path = "../rustc_hir" }
 rustc_hir_pretty = { path = "../rustc_hir_pretty" }
 rustc_metadata = { path = "../rustc_metadata" }
-rustc_mir = { path = "../rustc_mir" }
+rustc_const_eval = { path = "../rustc_const_eval" }
 rustc_parse = { path = "../rustc_parse" }
 rustc_plugin_impl = { path = "../rustc_plugin_impl" }
 rustc_save_analysis = { path = "../rustc_save_analysis" }
diff --git a/compiler/rustc_driver/src/pretty.rs b/compiler/rustc_driver/src/pretty.rs
index 579ba43b6d8e7..a25cc000443c7 100644
--- a/compiler/rustc_driver/src/pretty.rs
+++ b/compiler/rustc_driver/src/pretty.rs
@@ -6,8 +6,8 @@ use rustc_errors::ErrorReported;
 use rustc_hir as hir;
 use rustc_hir_pretty as pprust_hir;
 use rustc_middle::hir::map as hir_map;
+use rustc_middle::mir::{write_mir_graphviz, write_mir_pretty};
 use rustc_middle::ty::{self, TyCtxt};
-use rustc_mir::util::{write_mir_graphviz, write_mir_pretty};
 use rustc_session::config::{Input, PpAstTreeMode, PpHirMode, PpMode, PpSourceMode};
 use rustc_session::Session;
 use rustc_span::symbol::Ident;
diff --git a/compiler/rustc_interface/Cargo.toml b/compiler/rustc_interface/Cargo.toml
index dad5b256e42ab..e76fa6d8a1bc6 100644
--- a/compiler/rustc_interface/Cargo.toml
+++ b/compiler/rustc_interface/Cargo.toml
@@ -14,6 +14,7 @@ rayon = { version = "0.3.1", package = "rustc-rayon" }
 smallvec = { version = "1.6.1", features = ["union", "may_dangle"] }
 rustc_ast = { path = "../rustc_ast" }
 rustc_attr = { path = "../rustc_attr" }
+rustc_borrowck = { path = "../rustc_borrowck" }
 rustc_builtin_macros = { path = "../rustc_builtin_macros" }
 rustc_expand = { path = "../rustc_expand" }
 rustc_parse = { path = "../rustc_parse" }
@@ -31,8 +32,10 @@ rustc_symbol_mangling = { path = "../rustc_symbol_mangling" }
 rustc_codegen_llvm = { path = "../rustc_codegen_llvm", optional = true }
 rustc_hir = { path = "../rustc_hir" }
 rustc_metadata = { path = "../rustc_metadata" }
-rustc_mir = { path = "../rustc_mir" }
+rustc_const_eval = { path = "../rustc_const_eval" }
 rustc_mir_build = { path = "../rustc_mir_build" }
+rustc_mir_transform = { path = "../rustc_mir_transform" }
+rustc_monomorphize = { path = "../rustc_monomorphize" }
 rustc_passes = { path = "../rustc_passes" }
 rustc_typeck = { path = "../rustc_typeck" }
 rustc_lint = { path = "../rustc_lint" }
diff --git a/compiler/rustc_interface/src/passes.rs b/compiler/rustc_interface/src/passes.rs
index 1d542db9b69c3..1f3d6f70ff837 100644
--- a/compiler/rustc_interface/src/passes.rs
+++ b/compiler/rustc_interface/src/passes.rs
@@ -4,6 +4,7 @@ use crate::util;
 
 use rustc_ast::mut_visit::MutVisitor;
 use rustc_ast::{self as ast, visit};
+use rustc_borrowck as mir_borrowck;
 use rustc_codegen_ssa::back::link::emit_metadata;
 use rustc_codegen_ssa::traits::CodegenBackend;
 use rustc_data_structures::parallel;
@@ -21,7 +22,6 @@ use rustc_middle::middle;
 use rustc_middle::middle::cstore::{MetadataLoader, MetadataLoaderDyn};
 use rustc_middle::ty::query::Providers;
 use rustc_middle::ty::{self, GlobalCtxt, ResolverOutputs, TyCtxt};
-use rustc_mir as mir;
 use rustc_mir_build as mir_build;
 use rustc_parse::{parse_crate_from_file, parse_crate_from_source_str};
 use rustc_passes::{self, hir_stats, layout_test};
@@ -737,9 +737,12 @@ pub static DEFAULT_QUERY_PROVIDERS: SyncLazy<Providers> = SyncLazy::new(|| {
     let providers = &mut Providers::default();
     providers.analysis = analysis;
     proc_macro_decls::provide(providers);
+    rustc_const_eval::provide(providers);
     rustc_middle::hir::provide(providers);
-    mir::provide(providers);
+    mir_borrowck::provide(providers);
     mir_build::provide(providers);
+    rustc_mir_transform::provide(providers);
+    rustc_monomorphize::provide(providers);
     rustc_privacy::provide(providers);
     typeck::provide(providers);
     ty::provide(providers);
@@ -911,7 +914,7 @@ fn analysis(tcx: TyCtxt<'_>, (): ()) -> Result<()> {
         for def_id in tcx.body_owners() {
             tcx.ensure().thir_check_unsafety(def_id);
             if !tcx.sess.opts.debugging_opts.thir_unsafeck {
-                mir::transform::check_unsafety::check_unsafety(tcx, def_id);
+                rustc_mir_transform::check_unsafety::check_unsafety(tcx, def_id);
             }
 
             if tcx.hir().body_const_context(def_id).is_some() {
@@ -1059,7 +1062,7 @@ pub fn start_codegen<'tcx>(
     info!("Post-codegen\n{:?}", tcx.debug_stats());
 
     if tcx.sess.opts.output_types.contains_key(&OutputType::Mir) {
-        if let Err(e) = mir::transform::dump_mir::emit_mir(tcx, outputs) {
+        if let Err(e) = rustc_mir_transform::dump_mir::emit_mir(tcx, outputs) {
             tcx.sess.err(&format!("could not emit MIR: {}", e));
             tcx.sess.abort_if_errors();
         }
diff --git a/compiler/rustc_middle/Cargo.toml b/compiler/rustc_middle/Cargo.toml
index 2403ce2d24f55..68b83fccc85fd 100644
--- a/compiler/rustc_middle/Cargo.toml
+++ b/compiler/rustc_middle/Cargo.toml
@@ -9,6 +9,8 @@ doctest = false
 [dependencies]
 rustc_arena = { path = "../rustc_arena" }
 bitflags = "1.2.1"
+either = "1.5.0"
+gsgdt = "0.1.2"
 tracing = "0.1"
 rustc-rayon-core = "0.3.1"
 polonius-engine = "0.13.0"
@@ -21,6 +23,7 @@ rustc_macros = { path = "../rustc_macros" }
 rustc_data_structures = { path = "../rustc_data_structures" }
 rustc_query_system = { path = "../rustc_query_system" }
 rustc_errors = { path = "../rustc_errors" }
+rustc_graphviz = { path = "../rustc_graphviz" }
 rustc_index = { path = "../rustc_index" }
 rustc_serialize = { path = "../rustc_serialize" }
 rustc_ast = { path = "../rustc_ast" }
diff --git a/compiler/rustc_middle/src/lib.rs b/compiler/rustc_middle/src/lib.rs
index 6868be50f1d06..a366232c349d7 100644
--- a/compiler/rustc_middle/src/lib.rs
+++ b/compiler/rustc_middle/src/lib.rs
@@ -8,7 +8,7 @@
 //! - **MIR.** The "mid-level (M) intermediate representation (IR)" is
 //!   defined in the `mir` module. This module contains only the
 //!   *definition* of the MIR; the passes that transform and operate
-//!   on MIR are found in `rustc_mir` crate.
+//!   on MIR are found in `rustc_const_eval` crate.
 //! - **Types.** The internal representation of types used in rustc is
 //!   defined in the `ty` module. This includes the **type context**
 //!   (or `tcx`), which is the central context during most of
@@ -51,6 +51,8 @@
 #![feature(associated_type_defaults)]
 #![feature(iter_zip)]
 #![feature(thread_local_const_init)]
+#![feature(trusted_step)]
+#![feature(try_blocks)]
 #![feature(try_reserve)]
 #![feature(try_reserve_kind)]
 #![feature(nonzero_ops)]
diff --git a/compiler/rustc_mir/src/util/generic_graph.rs b/compiler/rustc_middle/src/mir/generic_graph.rs
similarity index 100%
rename from compiler/rustc_mir/src/util/generic_graph.rs
rename to compiler/rustc_middle/src/mir/generic_graph.rs
diff --git a/compiler/rustc_mir/src/util/generic_graphviz.rs b/compiler/rustc_middle/src/mir/generic_graphviz.rs
similarity index 100%
rename from compiler/rustc_mir/src/util/generic_graphviz.rs
rename to compiler/rustc_middle/src/mir/generic_graphviz.rs
diff --git a/compiler/rustc_mir/src/util/graphviz.rs b/compiler/rustc_middle/src/mir/graphviz.rs
similarity index 100%
rename from compiler/rustc_mir/src/util/graphviz.rs
rename to compiler/rustc_middle/src/mir/graphviz.rs
diff --git a/compiler/rustc_middle/src/mir/mod.rs b/compiler/rustc_middle/src/mir/mod.rs
index 83f6e79d5fcf6..38d4c5b4bd10e 100644
--- a/compiler/rustc_middle/src/mir/mod.rs
+++ b/compiler/rustc_middle/src/mir/mod.rs
@@ -42,11 +42,17 @@ pub use self::query::*;
 
 pub mod abstract_const;
 pub mod coverage;
+mod generic_graph;
+pub mod generic_graphviz;
 mod graph_cyclic_cache;
+pub mod graphviz;
 pub mod interpret;
 pub mod mono;
+pub mod patch;
 mod predecessors;
+pub mod pretty;
 mod query;
+pub mod spanview;
 pub mod tcx;
 pub mod terminator;
 pub use terminator::*;
@@ -54,6 +60,12 @@ pub mod traversal;
 mod type_foldable;
 pub mod visit;
 
+pub use self::generic_graph::graphviz_safe_def_name;
+pub use self::graphviz::write_mir_graphviz;
+pub use self::pretty::{
+    create_dump_file, display_allocation, dump_enabled, dump_mir, write_mir_pretty, PassWhere,
+};
+
 /// Types for locals
 pub type LocalDecls<'tcx> = IndexVec<Local, LocalDecl<'tcx>>;
 
@@ -75,6 +87,22 @@ impl<'tcx> HasLocalDecls<'tcx> for Body<'tcx> {
     }
 }
 
+/// A streamlined trait that you can implement to create a pass; the
+/// pass will be named after the type, and it will consist of a main
+/// loop that goes over each available MIR and applies `run_pass`.
+pub trait MirPass<'tcx> {
+    fn name(&self) -> Cow<'_, str> {
+        let name = std::any::type_name::<Self>();
+        if let Some(tail) = name.rfind(':') {
+            Cow::from(&name[tail + 1..])
+        } else {
+            Cow::from(name)
+        }
+    }
+
+    fn run_pass(&self, tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>);
+}
+
 /// The various "big phases" that MIR goes through.
 ///
 /// These phases all describe dialects of MIR. Since all MIR uses the same datastructures, the
@@ -1142,7 +1170,7 @@ rustc_index::newtype_index! {
     /// [CFG]: https://rustc-dev-guide.rust-lang.org/appendix/background.html#cfg
     /// [data-flow analyses]:
     ///     https://rustc-dev-guide.rust-lang.org/appendix/background.html#what-is-a-dataflow-analysis
-    /// [`CriticalCallEdges`]: ../../rustc_mir/transform/add_call_guards/enum.AddCallGuards.html#variant.CriticalCallEdges
+    /// [`CriticalCallEdges`]: ../../rustc_const_eval/transform/add_call_guards/enum.AddCallGuards.html#variant.CriticalCallEdges
     /// [guide-mir]: https://rustc-dev-guide.rust-lang.org/mir/
     pub struct BasicBlock {
         derive [HashStable]
diff --git a/compiler/rustc_mir/src/util/patch.rs b/compiler/rustc_middle/src/mir/patch.rs
similarity index 100%
rename from compiler/rustc_mir/src/util/patch.rs
rename to compiler/rustc_middle/src/mir/patch.rs
diff --git a/compiler/rustc_mir/src/util/pretty.rs b/compiler/rustc_middle/src/mir/pretty.rs
similarity index 99%
rename from compiler/rustc_mir/src/util/pretty.rs
rename to compiler/rustc_middle/src/mir/pretty.rs
index 92591db668ce9..db98cb763430f 100644
--- a/compiler/rustc_mir/src/util/pretty.rs
+++ b/compiler/rustc_middle/src/mir/pretty.rs
@@ -7,7 +7,6 @@ use std::path::{Path, PathBuf};
 
 use super::graphviz::write_mir_fn_graphviz;
 use super::spanview::write_mir_fn_spanview;
-use crate::transform::MirSource;
 use either::Either;
 use rustc_data_structures::fx::FxHashMap;
 use rustc_hir::def_id::DefId;
@@ -16,6 +15,7 @@ use rustc_middle::mir::interpret::{
     read_target_uint, AllocId, Allocation, ConstValue, GlobalAlloc, Pointer, Provenance,
 };
 use rustc_middle::mir::visit::Visitor;
+use rustc_middle::mir::MirSource;
 use rustc_middle::mir::*;
 use rustc_middle::ty::{self, TyCtxt, TyS, TypeFoldable, TypeVisitor};
 use rustc_target::abi::Size;
@@ -250,7 +250,7 @@ fn create_dump_file_with_basename(
 /// bit of MIR-related data. Used by `mir-dump`, but also by other
 /// bits of code (e.g., NLL inference) that dump graphviz data or
 /// other things, and hence takes the extension as an argument.
-pub(crate) fn create_dump_file(
+pub fn create_dump_file(
     tcx: TyCtxt<'_>,
     extension: &str,
     pass_num: Option<&dyn Display>,
diff --git a/compiler/rustc_middle/src/mir/query.rs b/compiler/rustc_middle/src/mir/query.rs
index 4fb737f463a86..1bdb6ca012b4a 100644
--- a/compiler/rustc_middle/src/mir/query.rs
+++ b/compiler/rustc_middle/src/mir/query.rs
@@ -219,7 +219,7 @@ pub struct BorrowCheckResult<'tcx> {
 /// The result of the `mir_const_qualif` query.
 ///
 /// Each field (except `error_occured`) corresponds to an implementer of the `Qualif` trait in
-/// `rustc_mir/src/transform/check_consts/qualifs.rs`. See that file for more information on each
+/// `rustc_const_eval/src/transform/check_consts/qualifs.rs`. See that file for more information on each
 /// `Qualif`.
 #[derive(Clone, Copy, Debug, Default, TyEncodable, TyDecodable, HashStable)]
 pub struct ConstQualifs {
@@ -313,7 +313,7 @@ pub struct ClosureOutlivesRequirement<'tcx> {
 /// are interesting (for error reporting). Order of variants indicates sort
 /// order of the category, thereby influencing diagnostic output.
 ///
-/// See also `rustc_mir::borrow_check::constraints`.
+/// See also `rustc_const_eval::borrow_check::constraints`.
 #[derive(Copy, Clone, Debug, Eq, PartialEq, PartialOrd, Ord, Hash)]
 #[derive(TyEncodable, TyDecodable, HashStable)]
 pub enum ConstraintCategory {
diff --git a/compiler/rustc_mir/src/util/spanview.rs b/compiler/rustc_middle/src/mir/spanview.rs
similarity index 100%
rename from compiler/rustc_mir/src/util/spanview.rs
rename to compiler/rustc_middle/src/mir/spanview.rs
diff --git a/compiler/rustc_middle/src/ty/sty.rs b/compiler/rustc_middle/src/ty/sty.rs
index 65dd61b63295c..0fbaf81c21e40 100644
--- a/compiler/rustc_middle/src/ty/sty.rs
+++ b/compiler/rustc_middle/src/ty/sty.rs
@@ -643,7 +643,7 @@ impl<'tcx> GeneratorSubsts<'tcx> {
     }
 
     /// This returns the types of the MIR locals which had to be stored across suspension points.
-    /// It is calculated in rustc_mir::transform::generator::StateTransform.
+    /// It is calculated in rustc_const_eval::transform::generator::StateTransform.
     /// All the types here must be in the tuple in GeneratorInterior.
     ///
     /// The locals are grouped by their variant number. Note that some locals may
@@ -1268,7 +1268,7 @@ pub type Region<'tcx> = &'tcx RegionKind;
 /// Representation of regions. Note that the NLL checker uses a distinct
 /// representation of regions. For this reason, it internally replaces all the
 /// regions with inference variables -- the index of the variable is then used
-/// to index into internal NLL data structures. See `rustc_mir::borrow_check`
+/// to index into internal NLL data structures. See `rustc_const_eval::borrow_check`
 /// module for more information.
 ///
 /// ## The Region lattice within a given function
diff --git a/compiler/rustc_mir/src/dataflow/mod.rs b/compiler/rustc_mir/src/dataflow/mod.rs
deleted file mode 100644
index 8a426cc1015cc..0000000000000
--- a/compiler/rustc_mir/src/dataflow/mod.rs
+++ /dev/null
@@ -1,49 +0,0 @@
-use rustc_ast::{self as ast, MetaItem};
-use rustc_middle::ty;
-use rustc_session::Session;
-use rustc_span::symbol::{sym, Symbol};
-
-pub(crate) use self::drop_flag_effects::*;
-pub use self::framework::{
-    fmt, graphviz, lattice, visit_results, Analysis, AnalysisDomain, Backward, BorrowckFlowState,
-    BorrowckResults, Engine, Forward, GenKill, GenKillAnalysis, JoinSemiLattice, Results,
-    ResultsCursor, ResultsRefCursor, ResultsVisitor, SwitchIntEdgeEffects,
-};
-
-use self::move_paths::MoveData;
-
-pub mod drop_flag_effects;
-mod framework;
-pub mod impls;
-pub mod move_paths;
-
-pub(crate) mod indexes {
-    pub(crate) use super::{
-        impls::borrows::BorrowIndex,
-        move_paths::{InitIndex, MoveOutIndex, MovePathIndex},
-    };
-}
-
-pub struct MoveDataParamEnv<'tcx> {
-    pub(crate) move_data: MoveData<'tcx>,
-    pub(crate) param_env: ty::ParamEnv<'tcx>,
-}
-
-pub(crate) fn has_rustc_mir_with(
-    _sess: &Session,
-    attrs: &[ast::Attribute],
-    name: Symbol,
-) -> Option<MetaItem> {
-    for attr in attrs {
-        if attr.has_name(sym::rustc_mir) {
-            let items = attr.meta_item_list();
-            for item in items.iter().flat_map(|l| l.iter()) {
-                match item.meta_item() {
-                    Some(mi) if mi.has_name(name) => return Some(mi.clone()),
-                    _ => continue,
-                }
-            }
-        }
-    }
-    None
-}
diff --git a/compiler/rustc_mir/src/util/mod.rs b/compiler/rustc_mir/src/util/mod.rs
deleted file mode 100644
index 3e466b5060feb..0000000000000
--- a/compiler/rustc_mir/src/util/mod.rs
+++ /dev/null
@@ -1,21 +0,0 @@
-pub mod aggregate;
-pub mod borrowck_errors;
-pub mod elaborate_drops;
-pub mod patch;
-pub mod storage;
-
-mod alignment;
-pub mod collect_writes;
-mod find_self_call;
-mod generic_graph;
-pub(crate) mod generic_graphviz;
-mod graphviz;
-pub(crate) mod pretty;
-pub(crate) mod spanview;
-
-pub use self::aggregate::expand_aggregate;
-pub use self::alignment::is_disaligned;
-pub use self::find_self_call::find_self_call;
-pub use self::generic_graph::graphviz_safe_def_name;
-pub use self::graphviz::write_mir_graphviz;
-pub use self::pretty::{dump_enabled, dump_mir, write_mir_fn, write_mir_pretty, PassWhere};
diff --git a/compiler/rustc_mir_dataflow/Cargo.toml b/compiler/rustc_mir_dataflow/Cargo.toml
new file mode 100644
index 0000000000000..3cd4892402e4c
--- /dev/null
+++ b/compiler/rustc_mir_dataflow/Cargo.toml
@@ -0,0 +1,23 @@
+[package]
+name = "rustc_mir_dataflow"
+version = "0.0.0"
+edition = "2018"
+
+[lib]
+doctest = false
+
+[dependencies]
+polonius-engine = "0.13.0"
+regex = "1"
+smallvec = { version = "1.6.1", features = ["union", "may_dangle"] }
+tracing = "0.1"
+rustc_ast = { path = "../rustc_ast" }
+rustc_data_structures = { path = "../rustc_data_structures" }
+rustc_graphviz = { path = "../rustc_graphviz" }
+rustc_hir = { path = "../rustc_hir" }
+rustc_index = { path = "../rustc_index" }
+rustc_middle = { path = "../rustc_middle" }
+rustc_serialize = { path = "../rustc_serialize" }
+rustc_session = { path = "../rustc_session" }
+rustc_target = { path = "../rustc_target" }
+rustc_span = { path = "../rustc_span" }
diff --git a/compiler/rustc_mir/src/dataflow/drop_flag_effects.rs b/compiler/rustc_mir_dataflow/src/drop_flag_effects.rs
similarity index 96%
rename from compiler/rustc_mir/src/dataflow/drop_flag_effects.rs
rename to compiler/rustc_mir_dataflow/src/drop_flag_effects.rs
index d16366fded900..e2269562b3d9b 100644
--- a/compiler/rustc_mir/src/dataflow/drop_flag_effects.rs
+++ b/compiler/rustc_mir_dataflow/src/drop_flag_effects.rs
@@ -1,4 +1,4 @@
-use crate::util::elaborate_drops::DropFlagState;
+use crate::elaborate_drops::DropFlagState;
 use rustc_middle::mir::{self, Body, Location};
 use rustc_middle::ty::{self, TyCtxt};
 use rustc_target::abi::VariantIdx;
@@ -79,7 +79,7 @@ fn place_contents_drop_state_cannot_differ<'tcx>(
     }
 }
 
-pub(crate) fn on_lookup_result_bits<'tcx, F>(
+pub fn on_lookup_result_bits<'tcx, F>(
     tcx: TyCtxt<'tcx>,
     body: &Body<'tcx>,
     move_data: &MoveData<'tcx>,
@@ -96,7 +96,7 @@ pub(crate) fn on_lookup_result_bits<'tcx, F>(
     }
 }
 
-pub(crate) fn on_all_children_bits<'tcx, F>(
+pub fn on_all_children_bits<'tcx, F>(
     tcx: TyCtxt<'tcx>,
     body: &Body<'tcx>,
     move_data: &MoveData<'tcx>,
@@ -138,7 +138,7 @@ pub(crate) fn on_all_children_bits<'tcx, F>(
     on_all_children_bits(tcx, body, move_data, move_path_index, &mut each_child);
 }
 
-pub(crate) fn on_all_drop_children_bits<'tcx, F>(
+pub fn on_all_drop_children_bits<'tcx, F>(
     tcx: TyCtxt<'tcx>,
     body: &Body<'tcx>,
     ctxt: &MoveDataParamEnv<'tcx>,
@@ -161,7 +161,7 @@ pub(crate) fn on_all_drop_children_bits<'tcx, F>(
     })
 }
 
-pub(crate) fn drop_flag_effects_for_function_entry<'tcx, F>(
+pub fn drop_flag_effects_for_function_entry<'tcx, F>(
     tcx: TyCtxt<'tcx>,
     body: &Body<'tcx>,
     ctxt: &MoveDataParamEnv<'tcx>,
@@ -179,7 +179,7 @@ pub(crate) fn drop_flag_effects_for_function_entry<'tcx, F>(
     }
 }
 
-pub(crate) fn drop_flag_effects_for_location<'tcx, F>(
+pub fn drop_flag_effects_for_location<'tcx, F>(
     tcx: TyCtxt<'tcx>,
     body: &Body<'tcx>,
     ctxt: &MoveDataParamEnv<'tcx>,
@@ -204,7 +204,7 @@ pub(crate) fn drop_flag_effects_for_location<'tcx, F>(
     for_location_inits(tcx, body, move_data, loc, |mpi| callback(mpi, DropFlagState::Present));
 }
 
-pub(crate) fn for_location_inits<'tcx, F>(
+pub fn for_location_inits<'tcx, F>(
     tcx: TyCtxt<'tcx>,
     body: &Body<'tcx>,
     move_data: &MoveData<'tcx>,
diff --git a/compiler/rustc_mir/src/util/elaborate_drops.rs b/compiler/rustc_mir_dataflow/src/elaborate_drops.rs
similarity index 99%
rename from compiler/rustc_mir/src/util/elaborate_drops.rs
rename to compiler/rustc_mir_dataflow/src/elaborate_drops.rs
index 50756fc15fb85..7607ccc3aba83 100644
--- a/compiler/rustc_mir/src/util/elaborate_drops.rs
+++ b/compiler/rustc_mir_dataflow/src/elaborate_drops.rs
@@ -1,7 +1,7 @@
-use crate::util::patch::MirPatch;
 use rustc_hir as hir;
 use rustc_hir::lang_items::LangItem;
 use rustc_index::vec::Idx;
+use rustc_middle::mir::patch::MirPatch;
 use rustc_middle::mir::*;
 use rustc_middle::traits::Reveal;
 use rustc_middle::ty::subst::SubstsRef;
diff --git a/compiler/rustc_mir/src/dataflow/framework/cursor.rs b/compiler/rustc_mir_dataflow/src/framework/cursor.rs
similarity index 100%
rename from compiler/rustc_mir/src/dataflow/framework/cursor.rs
rename to compiler/rustc_mir_dataflow/src/framework/cursor.rs
diff --git a/compiler/rustc_mir/src/dataflow/framework/direction.rs b/compiler/rustc_mir_dataflow/src/framework/direction.rs
similarity index 100%
rename from compiler/rustc_mir/src/dataflow/framework/direction.rs
rename to compiler/rustc_mir_dataflow/src/framework/direction.rs
diff --git a/compiler/rustc_mir/src/dataflow/framework/engine.rs b/compiler/rustc_mir_dataflow/src/framework/engine.rs
similarity index 99%
rename from compiler/rustc_mir/src/dataflow/framework/engine.rs
rename to compiler/rustc_mir_dataflow/src/framework/engine.rs
index 7ff7c860591fb..804abc3b42b53 100644
--- a/compiler/rustc_mir/src/dataflow/framework/engine.rs
+++ b/compiler/rustc_mir_dataflow/src/framework/engine.rs
@@ -11,6 +11,7 @@ use rustc_hir::def_id::DefId;
 use rustc_index::bit_set::BitSet;
 use rustc_index::vec::{Idx, IndexVec};
 use rustc_middle::mir::{self, traversal, BasicBlock};
+use rustc_middle::mir::{create_dump_file, dump_enabled};
 use rustc_middle::ty::TyCtxt;
 use rustc_span::symbol::{sym, Symbol};
 
@@ -20,7 +21,6 @@ use super::{
     visit_results, Analysis, Direction, GenKill, GenKillAnalysis, GenKillSet, JoinSemiLattice,
     ResultsCursor, ResultsVisitor,
 };
-use crate::util::pretty::{create_dump_file, dump_enabled};
 
 /// A dataflow analysis that has converged to fixpoint.
 pub struct Results<'tcx, A>
diff --git a/compiler/rustc_mir/src/dataflow/framework/fmt.rs b/compiler/rustc_mir_dataflow/src/framework/fmt.rs
similarity index 94%
rename from compiler/rustc_mir/src/dataflow/framework/fmt.rs
rename to compiler/rustc_mir_dataflow/src/framework/fmt.rs
index 35115ca9db756..1d1553bbbd984 100644
--- a/compiler/rustc_mir/src/dataflow/framework/fmt.rs
+++ b/compiler/rustc_mir_dataflow/src/framework/fmt.rs
@@ -147,18 +147,18 @@ where
 }
 
 impl<C> DebugWithContext<C> for rustc_middle::mir::Local {}
-impl<C> DebugWithContext<C> for crate::dataflow::move_paths::InitIndex {}
+impl<C> DebugWithContext<C> for crate::move_paths::InitIndex {}
 
-impl<'tcx, C> DebugWithContext<C> for crate::dataflow::move_paths::MovePathIndex
+impl<'tcx, C> DebugWithContext<C> for crate::move_paths::MovePathIndex
 where
-    C: crate::dataflow::move_paths::HasMoveData<'tcx>,
+    C: crate::move_paths::HasMoveData<'tcx>,
 {
     fn fmt_with(&self, ctxt: &C, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         write!(f, "{}", ctxt.move_data().move_paths[*self])
     }
 }
 
-impl<T, C> DebugWithContext<C> for crate::dataflow::lattice::Dual<T>
+impl<T, C> DebugWithContext<C> for crate::lattice::Dual<T>
 where
     T: DebugWithContext<C>,
 {
diff --git a/compiler/rustc_mir/src/dataflow/framework/graphviz.rs b/compiler/rustc_mir_dataflow/src/framework/graphviz.rs
similarity index 99%
rename from compiler/rustc_mir/src/dataflow/framework/graphviz.rs
rename to compiler/rustc_mir_dataflow/src/framework/graphviz.rs
index 4e54257a1cb2d..a370f8e40f9ae 100644
--- a/compiler/rustc_mir/src/dataflow/framework/graphviz.rs
+++ b/compiler/rustc_mir_dataflow/src/framework/graphviz.rs
@@ -6,11 +6,11 @@ use std::{io, ops, str};
 
 use regex::Regex;
 use rustc_graphviz as dot;
+use rustc_middle::mir::graphviz_safe_def_name;
 use rustc_middle::mir::{self, BasicBlock, Body, Location};
 
 use super::fmt::{DebugDiffWithAdapter, DebugWithAdapter, DebugWithContext};
 use super::{Analysis, Direction, Results, ResultsRefCursor, ResultsVisitor};
-use crate::util::graphviz_safe_def_name;
 
 #[derive(Clone, Copy, Debug, PartialEq, Eq)]
 pub enum OutputStyle {
diff --git a/compiler/rustc_mir/src/dataflow/framework/lattice.rs b/compiler/rustc_mir_dataflow/src/framework/lattice.rs
similarity index 100%
rename from compiler/rustc_mir/src/dataflow/framework/lattice.rs
rename to compiler/rustc_mir_dataflow/src/framework/lattice.rs
diff --git a/compiler/rustc_mir/src/dataflow/framework/mod.rs b/compiler/rustc_mir_dataflow/src/framework/mod.rs
similarity index 99%
rename from compiler/rustc_mir/src/dataflow/framework/mod.rs
rename to compiler/rustc_mir_dataflow/src/framework/mod.rs
index a5badc07d1017..f0c9ac4c504a3 100644
--- a/compiler/rustc_mir/src/dataflow/framework/mod.rs
+++ b/compiler/rustc_mir_dataflow/src/framework/mod.rs
@@ -11,7 +11,7 @@
 //! `visit_results`. The following example uses the `ResultsCursor` approach.
 //!
 //! ```ignore (cross-crate-imports)
-//! use rustc_mir::dataflow::Analysis; // Makes `into_engine` available.
+//! use rustc_const_eval::dataflow::Analysis; // Makes `into_engine` available.
 //!
 //! fn do_my_analysis(tcx: TyCtxt<'tcx>, body: &mir::Body<'tcx>) {
 //!     let analysis = MyAnalysis::new()
@@ -50,8 +50,7 @@ pub use self::cursor::{ResultsCursor, ResultsRefCursor};
 pub use self::direction::{Backward, Direction, Forward};
 pub use self::engine::{Engine, Results};
 pub use self::lattice::{JoinSemiLattice, MeetSemiLattice};
-pub use self::visitor::{visit_results, ResultsVisitor};
-pub use self::visitor::{BorrowckFlowState, BorrowckResults};
+pub use self::visitor::{visit_results, ResultsVisitable, ResultsVisitor};
 
 /// Define the domain of a dataflow problem.
 ///
diff --git a/compiler/rustc_mir/src/dataflow/framework/tests.rs b/compiler/rustc_mir_dataflow/src/framework/tests.rs
similarity index 100%
rename from compiler/rustc_mir/src/dataflow/framework/tests.rs
rename to compiler/rustc_mir_dataflow/src/framework/tests.rs
diff --git a/compiler/rustc_mir/src/dataflow/framework/visitor.rs b/compiler/rustc_mir_dataflow/src/framework/visitor.rs
similarity index 63%
rename from compiler/rustc_mir/src/dataflow/framework/visitor.rs
rename to compiler/rustc_mir_dataflow/src/framework/visitor.rs
index 82eb734ed0699..84136c4d78cf1 100644
--- a/compiler/rustc_mir/src/dataflow/framework/visitor.rs
+++ b/compiler/rustc_mir_dataflow/src/framework/visitor.rs
@@ -1,7 +1,6 @@
 use rustc_middle::mir::{self, BasicBlock, Location};
 
 use super::{Analysis, Direction, Results};
-use crate::dataflow::impls::{borrows::Borrows, EverInitializedPlaces, MaybeUninitializedPlaces};
 
 /// Calls the corresponding method in `ResultsVisitor` for every location in a `mir::Body` with the
 /// dataflow state at that location.
@@ -186,95 +185,3 @@ where
         self.analysis.apply_terminator_effect(state, term, loc);
     }
 }
-
-/// A tuple with named fields that can hold either the results or the transient state of the
-/// dataflow analyses used by the borrow checker.
-#[derive(Debug)]
-pub struct BorrowckAnalyses<B, U, E> {
-    pub borrows: B,
-    pub uninits: U,
-    pub ever_inits: E,
-}
-
-/// The results of the dataflow analyses used by the borrow checker.
-pub type BorrowckResults<'mir, 'tcx> = BorrowckAnalyses<
-    Results<'tcx, Borrows<'mir, 'tcx>>,
-    Results<'tcx, MaybeUninitializedPlaces<'mir, 'tcx>>,
-    Results<'tcx, EverInitializedPlaces<'mir, 'tcx>>,
->;
-
-/// The transient state of the dataflow analyses used by the borrow checker.
-pub type BorrowckFlowState<'mir, 'tcx> =
-    <BorrowckResults<'mir, 'tcx> as ResultsVisitable<'tcx>>::FlowState;
-
-macro_rules! impl_visitable {
-    ( $(
-        $T:ident { $( $field:ident : $A:ident ),* $(,)? }
-    )* ) => { $(
-        impl<'tcx, $($A),*, D: Direction> ResultsVisitable<'tcx> for $T<$( Results<'tcx, $A> ),*>
-        where
-            $( $A: Analysis<'tcx, Direction = D>, )*
-        {
-            type Direction = D;
-            type FlowState = $T<$( $A::Domain ),*>;
-
-            fn new_flow_state(&self, body: &mir::Body<'tcx>) -> Self::FlowState {
-                $T {
-                    $( $field: self.$field.analysis.bottom_value(body) ),*
-                }
-            }
-
-            fn reset_to_block_entry(
-                &self,
-                state: &mut Self::FlowState,
-                block: BasicBlock,
-            ) {
-                $( state.$field.clone_from(&self.$field.entry_set_for_block(block)); )*
-            }
-
-            fn reconstruct_before_statement_effect(
-                &self,
-                state: &mut Self::FlowState,
-                stmt: &mir::Statement<'tcx>,
-                loc: Location,
-            ) {
-                $( self.$field.analysis
-                    .apply_before_statement_effect(&mut state.$field, stmt, loc); )*
-            }
-
-            fn reconstruct_statement_effect(
-                &self,
-                state: &mut Self::FlowState,
-                stmt: &mir::Statement<'tcx>,
-                loc: Location,
-            ) {
-                $( self.$field.analysis
-                    .apply_statement_effect(&mut state.$field, stmt, loc); )*
-            }
-
-            fn reconstruct_before_terminator_effect(
-                &self,
-                state: &mut Self::FlowState,
-                term: &mir::Terminator<'tcx>,
-                loc: Location,
-            ) {
-                $( self.$field.analysis
-                    .apply_before_terminator_effect(&mut state.$field, term, loc); )*
-            }
-
-            fn reconstruct_terminator_effect(
-                &self,
-                state: &mut Self::FlowState,
-                term: &mir::Terminator<'tcx>,
-                loc: Location,
-            ) {
-                $( self.$field.analysis
-                    .apply_terminator_effect(&mut state.$field, term, loc); )*
-            }
-        }
-    )* }
-}
-
-impl_visitable! {
-    BorrowckAnalyses { borrows: B, uninits: U, ever_inits: E }
-}
diff --git a/compiler/rustc_mir/src/dataflow/impls/borrowed_locals.rs b/compiler/rustc_mir_dataflow/src/impls/borrowed_locals.rs
similarity index 99%
rename from compiler/rustc_mir/src/dataflow/impls/borrowed_locals.rs
rename to compiler/rustc_mir_dataflow/src/impls/borrowed_locals.rs
index 65e04ed6831cc..81d84f80ad4c1 100644
--- a/compiler/rustc_mir/src/dataflow/impls/borrowed_locals.rs
+++ b/compiler/rustc_mir_dataflow/src/impls/borrowed_locals.rs
@@ -1,6 +1,6 @@
-pub use super::*;
+use super::*;
 
-use crate::dataflow::{AnalysisDomain, GenKill, GenKillAnalysis};
+use crate::{AnalysisDomain, GenKill, GenKillAnalysis};
 use rustc_middle::mir::visit::Visitor;
 use rustc_middle::mir::*;
 use rustc_middle::ty::{ParamEnv, TyCtxt};
diff --git a/compiler/rustc_mir/src/dataflow/impls/init_locals.rs b/compiler/rustc_mir_dataflow/src/impls/init_locals.rs
similarity index 95%
rename from compiler/rustc_mir/src/dataflow/impls/init_locals.rs
rename to compiler/rustc_mir_dataflow/src/impls/init_locals.rs
index bb7292cd0337a..07570e764f5e0 100644
--- a/compiler/rustc_mir/src/dataflow/impls/init_locals.rs
+++ b/compiler/rustc_mir_dataflow/src/impls/init_locals.rs
@@ -2,7 +2,7 @@
 //!
 //! A local will be maybe initialized if *any* projections of that local might be initialized.
 
-use crate::dataflow::{self, GenKill};
+use crate::GenKill;
 
 use rustc_index::bit_set::BitSet;
 use rustc_middle::mir::visit::{PlaceContext, Visitor};
@@ -10,7 +10,7 @@ use rustc_middle::mir::{self, BasicBlock, Local, Location};
 
 pub struct MaybeInitializedLocals;
 
-impl dataflow::AnalysisDomain<'tcx> for MaybeInitializedLocals {
+impl crate::AnalysisDomain<'tcx> for MaybeInitializedLocals {
     type Domain = BitSet<Local>;
 
     const NAME: &'static str = "maybe_init_locals";
@@ -28,7 +28,7 @@ impl dataflow::AnalysisDomain<'tcx> for MaybeInitializedLocals {
     }
 }
 
-impl dataflow::GenKillAnalysis<'tcx> for MaybeInitializedLocals {
+impl crate::GenKillAnalysis<'tcx> for MaybeInitializedLocals {
     type Idx = Local;
 
     fn statement_effect(
diff --git a/compiler/rustc_mir/src/dataflow/impls/liveness.rs b/compiler/rustc_mir_dataflow/src/impls/liveness.rs
similarity index 98%
rename from compiler/rustc_mir/src/dataflow/impls/liveness.rs
rename to compiler/rustc_mir_dataflow/src/impls/liveness.rs
index 2d20f0d9547c1..0039d3188d57a 100644
--- a/compiler/rustc_mir/src/dataflow/impls/liveness.rs
+++ b/compiler/rustc_mir_dataflow/src/impls/liveness.rs
@@ -2,7 +2,7 @@ use rustc_index::bit_set::BitSet;
 use rustc_middle::mir::visit::{MutatingUseContext, NonMutatingUseContext, PlaceContext, Visitor};
 use rustc_middle::mir::{self, Local, Location};
 
-use crate::dataflow::{AnalysisDomain, Backward, GenKill, GenKillAnalysis};
+use crate::{AnalysisDomain, Backward, GenKill, GenKillAnalysis};
 
 /// A [live-variable dataflow analysis][liveness].
 ///
diff --git a/compiler/rustc_mir/src/dataflow/impls/mod.rs b/compiler/rustc_mir_dataflow/src/impls/mod.rs
similarity index 97%
rename from compiler/rustc_mir/src/dataflow/impls/mod.rs
rename to compiler/rustc_mir_dataflow/src/impls/mod.rs
index 185f0edfeb6bc..771ad90af28d6 100644
--- a/compiler/rustc_mir/src/dataflow/impls/mod.rs
+++ b/compiler/rustc_mir_dataflow/src/impls/mod.rs
@@ -7,27 +7,22 @@ use rustc_index::vec::Idx;
 use rustc_middle::mir::{self, Body, Location};
 use rustc_middle::ty::{self, TyCtxt};
 
-use super::MoveDataParamEnv;
-
-use crate::util::elaborate_drops::DropFlagState;
-
-use super::move_paths::{HasMoveData, InitIndex, InitKind, MoveData, MovePathIndex};
-use super::{lattice, AnalysisDomain, GenKill, GenKillAnalysis};
-
-use super::drop_flag_effects_for_function_entry;
-use super::drop_flag_effects_for_location;
-use super::on_lookup_result_bits;
-use crate::dataflow::drop_flag_effects;
-use crate::dataflow::framework::SwitchIntEdgeEffects;
+use crate::drop_flag_effects;
+use crate::drop_flag_effects_for_function_entry;
+use crate::drop_flag_effects_for_location;
+use crate::elaborate_drops::DropFlagState;
+use crate::framework::SwitchIntEdgeEffects;
+use crate::move_paths::{HasMoveData, InitIndex, InitKind, MoveData, MovePathIndex};
+use crate::on_lookup_result_bits;
+use crate::MoveDataParamEnv;
+use crate::{lattice, AnalysisDomain, GenKill, GenKillAnalysis};
 
 mod borrowed_locals;
-pub(super) mod borrows;
 mod init_locals;
 mod liveness;
 mod storage_liveness;
 
 pub use self::borrowed_locals::{MaybeBorrowedLocals, MaybeMutBorrowedLocals};
-pub use self::borrows::Borrows;
 pub use self::init_locals::MaybeInitializedLocals;
 pub use self::liveness::MaybeLiveLocals;
 pub use self::storage_liveness::{MaybeRequiresStorage, MaybeStorageLive};
diff --git a/compiler/rustc_mir/src/dataflow/impls/storage_liveness.rs b/compiler/rustc_mir_dataflow/src/impls/storage_liveness.rs
similarity index 96%
rename from compiler/rustc_mir/src/dataflow/impls/storage_liveness.rs
rename to compiler/rustc_mir_dataflow/src/impls/storage_liveness.rs
index 792664597fd9a..b468e50b391ca 100644
--- a/compiler/rustc_mir/src/dataflow/impls/storage_liveness.rs
+++ b/compiler/rustc_mir_dataflow/src/impls/storage_liveness.rs
@@ -1,7 +1,7 @@
 pub use super::*;
 
-use crate::dataflow::{self, GenKill, Results, ResultsRefCursor};
-use crate::util::storage::AlwaysLiveLocals;
+use crate::storage::AlwaysLiveLocals;
+use crate::{GenKill, Results, ResultsRefCursor};
 use rustc_middle::mir::visit::{NonMutatingUseContext, PlaceContext, Visitor};
 use rustc_middle::mir::*;
 use std::cell::RefCell;
@@ -17,7 +17,7 @@ impl MaybeStorageLive {
     }
 }
 
-impl dataflow::AnalysisDomain<'tcx> for MaybeStorageLive {
+impl crate::AnalysisDomain<'tcx> for MaybeStorageLive {
     type Domain = BitSet<Local>;
 
     const NAME: &'static str = "maybe_storage_live";
@@ -39,7 +39,7 @@ impl dataflow::AnalysisDomain<'tcx> for MaybeStorageLive {
     }
 }
 
-impl dataflow::GenKillAnalysis<'tcx> for MaybeStorageLive {
+impl crate::GenKillAnalysis<'tcx> for MaybeStorageLive {
     type Idx = Local;
 
     fn statement_effect(
@@ -97,7 +97,7 @@ impl<'mir, 'tcx> MaybeRequiresStorage<'mir, 'tcx> {
     }
 }
 
-impl<'mir, 'tcx> dataflow::AnalysisDomain<'tcx> for MaybeRequiresStorage<'mir, 'tcx> {
+impl<'mir, 'tcx> crate::AnalysisDomain<'tcx> for MaybeRequiresStorage<'mir, 'tcx> {
     type Domain = BitSet<Local>;
 
     const NAME: &'static str = "requires_storage";
@@ -116,7 +116,7 @@ impl<'mir, 'tcx> dataflow::AnalysisDomain<'tcx> for MaybeRequiresStorage<'mir, '
     }
 }
 
-impl<'mir, 'tcx> dataflow::GenKillAnalysis<'tcx> for MaybeRequiresStorage<'mir, 'tcx> {
+impl<'mir, 'tcx> crate::GenKillAnalysis<'tcx> for MaybeRequiresStorage<'mir, 'tcx> {
     type Idx = Local;
 
     fn before_statement_effect(
diff --git a/compiler/rustc_mir_dataflow/src/lib.rs b/compiler/rustc_mir_dataflow/src/lib.rs
new file mode 100644
index 0000000000000..bfae09b7760a0
--- /dev/null
+++ b/compiler/rustc_mir_dataflow/src/lib.rs
@@ -0,0 +1,72 @@
+#![feature(associated_type_defaults)]
+#![feature(bool_to_option)]
+#![feature(box_patterns)]
+#![feature(box_syntax)]
+#![feature(const_panic)]
+#![feature(exact_size_is_empty)]
+#![feature(in_band_lifetimes)]
+#![feature(iter_zip)]
+#![feature(min_specialization)]
+#![feature(once_cell)]
+#![feature(stmt_expr_attributes)]
+#![feature(trusted_step)]
+#![recursion_limit = "256"]
+
+#[macro_use]
+extern crate tracing;
+#[macro_use]
+extern crate rustc_middle;
+
+use rustc_ast::{self as ast, MetaItem};
+use rustc_middle::ty;
+use rustc_session::Session;
+use rustc_span::symbol::{sym, Symbol};
+
+pub use self::drop_flag_effects::{
+    drop_flag_effects_for_function_entry, drop_flag_effects_for_location,
+    move_path_children_matching, on_all_children_bits, on_all_drop_children_bits,
+    on_lookup_result_bits,
+};
+pub use self::framework::{
+    fmt, lattice, visit_results, Analysis, AnalysisDomain, Backward, Direction, Engine, Forward,
+    GenKill, GenKillAnalysis, JoinSemiLattice, Results, ResultsCursor, ResultsRefCursor,
+    ResultsVisitable, ResultsVisitor,
+};
+
+use self::move_paths::MoveData;
+
+pub mod drop_flag_effects;
+pub mod elaborate_drops;
+mod framework;
+pub mod impls;
+pub mod move_paths;
+pub mod rustc_peek;
+pub mod storage;
+
+pub(crate) mod indexes {
+    pub(crate) use super::move_paths::MovePathIndex;
+}
+
+pub struct MoveDataParamEnv<'tcx> {
+    pub move_data: MoveData<'tcx>,
+    pub param_env: ty::ParamEnv<'tcx>,
+}
+
+pub fn has_rustc_mir_with(
+    _sess: &Session,
+    attrs: &[ast::Attribute],
+    name: Symbol,
+) -> Option<MetaItem> {
+    for attr in attrs {
+        if attr.has_name(sym::rustc_mir) {
+            let items = attr.meta_item_list();
+            for item in items.iter().flat_map(|l| l.iter()) {
+                match item.meta_item() {
+                    Some(mi) if mi.has_name(name) => return Some(mi.clone()),
+                    _ => continue,
+                }
+            }
+        }
+    }
+    None
+}
diff --git a/compiler/rustc_mir/src/dataflow/move_paths/abs_domain.rs b/compiler/rustc_mir_dataflow/src/move_paths/abs_domain.rs
similarity index 100%
rename from compiler/rustc_mir/src/dataflow/move_paths/abs_domain.rs
rename to compiler/rustc_mir_dataflow/src/move_paths/abs_domain.rs
diff --git a/compiler/rustc_mir/src/dataflow/move_paths/builder.rs b/compiler/rustc_mir_dataflow/src/move_paths/builder.rs
similarity index 100%
rename from compiler/rustc_mir/src/dataflow/move_paths/builder.rs
rename to compiler/rustc_mir_dataflow/src/move_paths/builder.rs
diff --git a/compiler/rustc_mir/src/dataflow/move_paths/mod.rs b/compiler/rustc_mir_dataflow/src/move_paths/mod.rs
similarity index 97%
rename from compiler/rustc_mir/src/dataflow/move_paths/mod.rs
rename to compiler/rustc_mir_dataflow/src/move_paths/mod.rs
index 7c63025918603..699ec4bbff80f 100644
--- a/compiler/rustc_mir/src/dataflow/move_paths/mod.rs
+++ b/compiler/rustc_mir_dataflow/src/move_paths/mod.rs
@@ -19,6 +19,12 @@ rustc_index::newtype_index! {
     }
 }
 
+impl polonius_engine::Atom for MovePathIndex {
+    fn index(self) -> usize {
+        rustc_index::vec::Idx::index(self)
+    }
+}
+
 rustc_index::newtype_index! {
     pub struct MoveOutIndex {
         DEBUG_FORMAT = "mo{}"
@@ -276,7 +282,7 @@ impl fmt::Debug for Init {
 }
 
 impl Init {
-    crate fn span<'tcx>(&self, body: &Body<'tcx>) -> Span {
+    pub fn span<'tcx>(&self, body: &Body<'tcx>) -> Span {
         match self.location {
             InitLocation::Argument(local) => body.local_decls[local].source_info.span,
             InitLocation::Statement(location) => body.source_info(location).span,
@@ -338,12 +344,12 @@ impl MovePathLookup {
 
 #[derive(Debug)]
 pub struct IllegalMoveOrigin<'tcx> {
-    pub(crate) location: Location,
-    pub(crate) kind: IllegalMoveOriginKind<'tcx>,
+    pub location: Location,
+    pub kind: IllegalMoveOriginKind<'tcx>,
 }
 
 #[derive(Debug)]
-pub(crate) enum IllegalMoveOriginKind<'tcx> {
+pub enum IllegalMoveOriginKind<'tcx> {
     /// Illegal move due to attempt to move from behind a reference.
     BorrowedContent {
         /// The place the reference refers to: if erroneous code was trying to
diff --git a/compiler/rustc_mir/src/transform/rustc_peek.rs b/compiler/rustc_mir_dataflow/src/rustc_peek.rs
similarity index 96%
rename from compiler/rustc_mir/src/transform/rustc_peek.rs
rename to compiler/rustc_mir_dataflow/src/rustc_peek.rs
index f4a1b0ddba53f..29ffed9934421 100644
--- a/compiler/rustc_mir/src/transform/rustc_peek.rs
+++ b/compiler/rustc_mir_dataflow/src/rustc_peek.rs
@@ -5,25 +5,25 @@ use rustc_span::symbol::sym;
 use rustc_span::Span;
 use rustc_target::spec::abi::Abi;
 
-use crate::transform::MirPass;
 use rustc_index::bit_set::BitSet;
+use rustc_middle::mir::MirPass;
 use rustc_middle::mir::{self, Body, Local, Location};
 use rustc_middle::ty::{self, Ty, TyCtxt};
 
-use crate::dataflow::impls::{
+use crate::impls::{
     DefinitelyInitializedPlaces, MaybeInitializedPlaces, MaybeLiveLocals, MaybeMutBorrowedLocals,
     MaybeUninitializedPlaces,
 };
-use crate::dataflow::move_paths::{HasMoveData, MoveData};
-use crate::dataflow::move_paths::{LookupResult, MovePathIndex};
-use crate::dataflow::MoveDataParamEnv;
-use crate::dataflow::{Analysis, JoinSemiLattice, Results, ResultsCursor};
+use crate::move_paths::{HasMoveData, MoveData};
+use crate::move_paths::{LookupResult, MovePathIndex};
+use crate::MoveDataParamEnv;
+use crate::{Analysis, JoinSemiLattice, Results, ResultsCursor};
 
 pub struct SanityCheck;
 
 impl<'tcx> MirPass<'tcx> for SanityCheck {
     fn run_pass(&self, tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) {
-        use crate::dataflow::has_rustc_mir_with;
+        use crate::has_rustc_mir_with;
         let def_id = body.source.def_id();
         if !tcx.has_attr(def_id, sym::rustc_mir) {
             debug!("skipping rustc_peek::SanityCheck on {}", tcx.def_path_str(def_id));
diff --git a/compiler/rustc_mir/src/util/storage.rs b/compiler/rustc_mir_dataflow/src/storage.rs
similarity index 100%
rename from compiler/rustc_mir/src/util/storage.rs
rename to compiler/rustc_mir_dataflow/src/storage.rs
diff --git a/compiler/rustc_mir_transform/Cargo.toml b/compiler/rustc_mir_transform/Cargo.toml
new file mode 100644
index 0000000000000..5e1a587b0ecea
--- /dev/null
+++ b/compiler/rustc_mir_transform/Cargo.toml
@@ -0,0 +1,29 @@
+[package]
+name = "rustc_mir_transform"
+version = "0.0.0"
+edition = "2018"
+
+[lib]
+doctest = false
+
+[dependencies]
+itertools = "0.9"
+smallvec = { version = "1.6.1", features = ["union", "may_dangle"] }
+tracing = "0.1"
+rustc_ast = { path = "../rustc_ast" }
+rustc_attr = { path = "../rustc_attr" }
+rustc_data_structures = { path = "../rustc_data_structures" }
+rustc_errors = { path = "../rustc_errors" }
+rustc_hir = { path = "../rustc_hir" }
+rustc_index = { path = "../rustc_index" }
+rustc_middle = { path = "../rustc_middle" }
+rustc_const_eval = { path = "../rustc_const_eval" }
+rustc_mir_dataflow = { path = "../rustc_mir_dataflow" }
+rustc_serialize = { path = "../rustc_serialize" }
+rustc_session = { path = "../rustc_session" }
+rustc_target = { path = "../rustc_target" }
+rustc_trait_selection = { path = "../rustc_trait_selection" }
+rustc_span = { path = "../rustc_span" }
+
+[dev-dependencies]
+coverage_test_macros = { path = "src/coverage/test_macros" }
diff --git a/compiler/rustc_mir/src/transform/abort_unwinding_calls.rs b/compiler/rustc_mir_transform/src/abort_unwinding_calls.rs
similarity index 99%
rename from compiler/rustc_mir/src/transform/abort_unwinding_calls.rs
rename to compiler/rustc_mir_transform/src/abort_unwinding_calls.rs
index aecb2373eaf36..855dcbc431b1e 100644
--- a/compiler/rustc_mir/src/transform/abort_unwinding_calls.rs
+++ b/compiler/rustc_mir_transform/src/abort_unwinding_calls.rs
@@ -1,4 +1,4 @@
-use crate::transform::MirPass;
+use crate::MirPass;
 use rustc_hir::def::DefKind;
 use rustc_middle::middle::codegen_fn_attrs::CodegenFnAttrFlags;
 use rustc_middle::mir::*;
diff --git a/compiler/rustc_mir/src/transform/add_call_guards.rs b/compiler/rustc_mir_transform/src/add_call_guards.rs
similarity index 98%
rename from compiler/rustc_mir/src/transform/add_call_guards.rs
rename to compiler/rustc_mir_transform/src/add_call_guards.rs
index 12ee6bb4c67fa..cd6b671a0dbfd 100644
--- a/compiler/rustc_mir/src/transform/add_call_guards.rs
+++ b/compiler/rustc_mir_transform/src/add_call_guards.rs
@@ -1,4 +1,4 @@
-use crate::transform::MirPass;
+use crate::MirPass;
 use rustc_index::vec::{Idx, IndexVec};
 use rustc_middle::mir::*;
 use rustc_middle::ty::TyCtxt;
diff --git a/compiler/rustc_mir/src/transform/add_moves_for_packed_drops.rs b/compiler/rustc_mir_transform/src/add_moves_for_packed_drops.rs
similarity index 98%
rename from compiler/rustc_mir/src/transform/add_moves_for_packed_drops.rs
rename to compiler/rustc_mir_transform/src/add_moves_for_packed_drops.rs
index 417e0a51aecf0..9eaf2b6a21113 100644
--- a/compiler/rustc_mir/src/transform/add_moves_for_packed_drops.rs
+++ b/compiler/rustc_mir_transform/src/add_moves_for_packed_drops.rs
@@ -1,9 +1,9 @@
 use rustc_middle::mir::*;
 use rustc_middle::ty::TyCtxt;
 
-use crate::transform::MirPass;
 use crate::util;
-use crate::util::patch::MirPatch;
+use crate::MirPass;
+use rustc_middle::mir::patch::MirPatch;
 
 // This pass moves values being dropped that are within a packed
 // struct to a separate local before dropping them, to ensure that
diff --git a/compiler/rustc_mir/src/transform/add_retag.rs b/compiler/rustc_mir_transform/src/add_retag.rs
similarity index 99%
rename from compiler/rustc_mir/src/transform/add_retag.rs
rename to compiler/rustc_mir_transform/src/add_retag.rs
index cb608819ea8ac..7a8dee09c29f0 100644
--- a/compiler/rustc_mir/src/transform/add_retag.rs
+++ b/compiler/rustc_mir_transform/src/add_retag.rs
@@ -4,7 +4,7 @@
 //! of MIR building, and only after this pass we think of the program has having the
 //! normal MIR semantics.
 
-use crate::transform::MirPass;
+use crate::MirPass;
 use rustc_middle::mir::*;
 use rustc_middle::ty::{self, Ty, TyCtxt};
 
diff --git a/compiler/rustc_mir/src/transform/check_const_item_mutation.rs b/compiler/rustc_mir_transform/src/check_const_item_mutation.rs
similarity index 99%
rename from compiler/rustc_mir/src/transform/check_const_item_mutation.rs
rename to compiler/rustc_mir_transform/src/check_const_item_mutation.rs
index e2d50ba034ad3..27fe80a456f7d 100644
--- a/compiler/rustc_mir/src/transform/check_const_item_mutation.rs
+++ b/compiler/rustc_mir_transform/src/check_const_item_mutation.rs
@@ -6,7 +6,7 @@ use rustc_middle::ty::TyCtxt;
 use rustc_session::lint::builtin::CONST_ITEM_MUTATION;
 use rustc_span::def_id::DefId;
 
-use crate::transform::MirPass;
+use crate::MirPass;
 
 pub struct CheckConstItemMutation;
 
diff --git a/compiler/rustc_mir/src/transform/check_packed_ref.rs b/compiler/rustc_mir_transform/src/check_packed_ref.rs
similarity index 99%
rename from compiler/rustc_mir/src/transform/check_packed_ref.rs
rename to compiler/rustc_mir_transform/src/check_packed_ref.rs
index 13b7221046bda..49be34c7a2845 100644
--- a/compiler/rustc_mir/src/transform/check_packed_ref.rs
+++ b/compiler/rustc_mir_transform/src/check_packed_ref.rs
@@ -6,8 +6,8 @@ use rustc_middle::ty::{self, TyCtxt};
 use rustc_session::lint::builtin::UNALIGNED_REFERENCES;
 use rustc_span::symbol::sym;
 
-use crate::transform::MirPass;
 use crate::util;
+use crate::MirPass;
 
 pub(crate) fn provide(providers: &mut Providers) {
     *providers = Providers { unsafe_derive_on_repr_packed, ..*providers };
diff --git a/compiler/rustc_mir/src/transform/check_unsafety.rs b/compiler/rustc_mir_transform/src/check_unsafety.rs
similarity index 100%
rename from compiler/rustc_mir/src/transform/check_unsafety.rs
rename to compiler/rustc_mir_transform/src/check_unsafety.rs
diff --git a/compiler/rustc_mir/src/transform/cleanup_post_borrowck.rs b/compiler/rustc_mir_transform/src/cleanup_post_borrowck.rs
similarity index 98%
rename from compiler/rustc_mir/src/transform/cleanup_post_borrowck.rs
rename to compiler/rustc_mir_transform/src/cleanup_post_borrowck.rs
index 8ff0fae768618..611d29a4ee29a 100644
--- a/compiler/rustc_mir/src/transform/cleanup_post_borrowck.rs
+++ b/compiler/rustc_mir_transform/src/cleanup_post_borrowck.rs
@@ -18,7 +18,7 @@
 //! [`ForMatchGuard`]: rustc_middle::mir::FakeReadCause::ForMatchGuard
 //! [`Nop`]: rustc_middle::mir::StatementKind::Nop
 
-use crate::transform::MirPass;
+use crate::MirPass;
 use rustc_middle::mir::visit::MutVisitor;
 use rustc_middle::mir::{Body, BorrowKind, Location, Rvalue};
 use rustc_middle::mir::{Statement, StatementKind};
diff --git a/compiler/rustc_mir/src/transform/const_debuginfo.rs b/compiler/rustc_mir_transform/src/const_debuginfo.rs
similarity index 99%
rename from compiler/rustc_mir/src/transform/const_debuginfo.rs
rename to compiler/rustc_mir_transform/src/const_debuginfo.rs
index 3cdaf4c7dcd47..b613634560fbd 100644
--- a/compiler/rustc_mir/src/transform/const_debuginfo.rs
+++ b/compiler/rustc_mir_transform/src/const_debuginfo.rs
@@ -9,7 +9,7 @@ use rustc_middle::{
     ty::TyCtxt,
 };
 
-use crate::transform::MirPass;
+use crate::MirPass;
 use rustc_index::{bit_set::BitSet, vec::IndexVec};
 
 pub struct ConstDebugInfo;
diff --git a/compiler/rustc_mir/src/transform/const_goto.rs b/compiler/rustc_mir_transform/src/const_goto.rs
similarity index 99%
rename from compiler/rustc_mir/src/transform/const_goto.rs
rename to compiler/rustc_mir_transform/src/const_goto.rs
index ba10b54c5ae2e..d319fdcaa6b7e 100644
--- a/compiler/rustc_mir/src/transform/const_goto.rs
+++ b/compiler/rustc_mir_transform/src/const_goto.rs
@@ -17,7 +17,7 @@
 //! }
 //! ```
 
-use crate::transform::MirPass;
+use crate::MirPass;
 use rustc_middle::mir::*;
 use rustc_middle::ty::TyCtxt;
 use rustc_middle::{mir::visit::Visitor, ty::ParamEnv};
diff --git a/compiler/rustc_mir/src/transform/const_prop.rs b/compiler/rustc_mir_transform/src/const_prop.rs
similarity index 99%
rename from compiler/rustc_mir/src/transform/const_prop.rs
rename to compiler/rustc_mir_transform/src/const_prop.rs
index 71c07be4c6d8d..71b3a555587f7 100644
--- a/compiler/rustc_mir/src/transform/const_prop.rs
+++ b/compiler/rustc_mir_transform/src/const_prop.rs
@@ -28,13 +28,13 @@ use rustc_target::abi::{HasDataLayout, Size, TargetDataLayout};
 use rustc_target::spec::abi::Abi;
 use rustc_trait_selection::traits;
 
-use crate::const_eval::ConstEvalErr;
-use crate::interpret::{
+use crate::MirPass;
+use rustc_const_eval::const_eval::ConstEvalErr;
+use rustc_const_eval::interpret::{
     self, compile_time_machine, AllocId, Allocation, ConstValue, CtfeValidationMode, Frame, ImmTy,
     Immediate, InterpCx, InterpResult, LocalState, LocalValue, MemPlace, MemoryKind, OpTy,
     Operand as InterpOperand, PlaceTy, Scalar, ScalarMaybeUninit, StackPopCleanup, StackPopUnwind,
 };
-use crate::transform::MirPass;
 
 /// The maximum number of bytes that we'll allocate space for a local or the return value.
 /// Needed for #66397, because otherwise we eval into large places and that can cause OOM or just
diff --git a/compiler/rustc_mir/src/transform/coverage/counters.rs b/compiler/rustc_mir_transform/src/coverage/counters.rs
similarity index 100%
rename from compiler/rustc_mir/src/transform/coverage/counters.rs
rename to compiler/rustc_mir_transform/src/coverage/counters.rs
diff --git a/compiler/rustc_mir/src/transform/coverage/debug.rs b/compiler/rustc_mir_transform/src/coverage/debug.rs
similarity index 97%
rename from compiler/rustc_mir/src/transform/coverage/debug.rs
rename to compiler/rustc_mir_transform/src/coverage/debug.rs
index 464079656f9fb..513a85b591306 100644
--- a/compiler/rustc_mir/src/transform/coverage/debug.rs
+++ b/compiler/rustc_mir_transform/src/coverage/debug.rs
@@ -44,7 +44,7 @@
 //! points, which can be enabled via environment variable:
 //!
 //! ```shell
-//! RUSTC_LOG=rustc_mir::transform::coverage=debug
+//! RUSTC_LOG=rustc_mir_transform::transform::coverage=debug
 //! ```
 //!
 //! Other module paths with coverage-related debug logs may also be of interest, particularly for
@@ -52,7 +52,7 @@
 //! code generation pass). For example:
 //!
 //! ```shell
-//! RUSTC_LOG=rustc_mir::transform::coverage,rustc_codegen_ssa::coverageinfo,rustc_codegen_llvm::coverageinfo=debug
+//! RUSTC_LOG=rustc_mir_transform::transform::coverage,rustc_codegen_ssa::coverageinfo,rustc_codegen_llvm::coverageinfo=debug
 //! ```
 //!
 //! Coverage Debug Options
@@ -111,9 +111,9 @@
 use super::graph::{BasicCoverageBlock, BasicCoverageBlockData, CoverageGraph};
 use super::spans::CoverageSpan;
 
-use crate::util::generic_graphviz::GraphvizWriter;
-use crate::util::pretty;
-use crate::util::spanview::{self, SpanViewable};
+use rustc_middle::mir::create_dump_file;
+use rustc_middle::mir::generic_graphviz::GraphvizWriter;
+use rustc_middle::mir::spanview::{self, SpanViewable};
 
 use rustc_data_structures::fx::FxHashMap;
 use rustc_middle::mir::coverage::*;
@@ -181,13 +181,11 @@ impl DebugOptions {
                             }
                         };
                     }
-                    _ => {
-                        bug!(
-                            "Unsupported setting `{}` in environment variable {}",
-                            option,
-                            RUSTC_COVERAGE_DEBUG_OPTIONS
-                        )
-                    }
+                    _ => bug!(
+                        "Unsupported setting `{}` in environment variable {}",
+                        option,
+                        RUSTC_COVERAGE_DEBUG_OPTIONS
+                    ),
                 };
             }
         }
@@ -643,7 +641,7 @@ pub(super) fn dump_coverage_spanview(
     let def_id = mir_source.def_id();
 
     let span_viewables = span_viewables(tcx, mir_body, basic_coverage_blocks, &coverage_spans);
-    let mut file = pretty::create_dump_file(tcx, "html", None, pass_name, &0, mir_source)
+    let mut file = create_dump_file(tcx, "html", None, pass_name, &0, mir_source)
         .expect("Unexpected error creating MIR spanview HTML file");
     let crate_name = tcx.crate_name(def_id.krate);
     let item_name = tcx.def_path(def_id).to_filename_friendly_no_crate();
@@ -745,7 +743,7 @@ pub(super) fn dump_coverage_graphviz(
                 .join("\n  ")
         ));
     }
-    let mut file = pretty::create_dump_file(tcx, "dot", None, pass_name, &0, mir_source)
+    let mut file = create_dump_file(tcx, "dot", None, pass_name, &0, mir_source)
         .expect("Unexpected error creating BasicCoverageBlock graphviz DOT file");
     graphviz_writer
         .write_graphviz(tcx, &mut file)
diff --git a/compiler/rustc_mir/src/transform/coverage/graph.rs b/compiler/rustc_mir_transform/src/coverage/graph.rs
similarity index 100%
rename from compiler/rustc_mir/src/transform/coverage/graph.rs
rename to compiler/rustc_mir_transform/src/coverage/graph.rs
diff --git a/compiler/rustc_mir/src/transform/coverage/mod.rs b/compiler/rustc_mir_transform/src/coverage/mod.rs
similarity index 99%
rename from compiler/rustc_mir/src/transform/coverage/mod.rs
rename to compiler/rustc_mir_transform/src/coverage/mod.rs
index f7fbea6ad5371..6043606c37957 100644
--- a/compiler/rustc_mir/src/transform/coverage/mod.rs
+++ b/compiler/rustc_mir_transform/src/coverage/mod.rs
@@ -12,8 +12,7 @@ use counters::CoverageCounters;
 use graph::{BasicCoverageBlock, BasicCoverageBlockData, CoverageGraph};
 use spans::{CoverageSpan, CoverageSpans};
 
-use crate::transform::MirPass;
-use crate::util::pretty;
+use crate::MirPass;
 
 use rustc_data_structures::fingerprint::Fingerprint;
 use rustc_data_structures::graph::WithNumNodes;
@@ -25,6 +24,7 @@ use rustc_middle::hir::map::blocks::FnLikeNode;
 use rustc_middle::ich::StableHashingContext;
 use rustc_middle::middle::codegen_fn_attrs::CodegenFnAttrFlags;
 use rustc_middle::mir::coverage::*;
+use rustc_middle::mir::dump_enabled;
 use rustc_middle::mir::{
     self, BasicBlock, BasicBlockData, Coverage, SourceInfo, Statement, StatementKind, Terminator,
     TerminatorKind,
@@ -159,7 +159,7 @@ impl<'a, 'tcx> Instrumentor<'a, 'tcx> {
         let mut graphviz_data = debug::GraphvizData::new();
         let mut debug_used_expressions = debug::UsedExpressions::new();
 
-        let dump_mir = pretty::dump_enabled(tcx, self.pass_name, def_id);
+        let dump_mir = dump_enabled(tcx, self.pass_name, def_id);
         let dump_graphviz = dump_mir && tcx.sess.opts.debugging_opts.dump_mir_graphviz;
         let dump_spanview = dump_mir && tcx.sess.opts.debugging_opts.dump_mir_spanview.is_some();
 
diff --git a/compiler/rustc_mir/src/transform/coverage/query.rs b/compiler/rustc_mir_transform/src/coverage/query.rs
similarity index 100%
rename from compiler/rustc_mir/src/transform/coverage/query.rs
rename to compiler/rustc_mir_transform/src/coverage/query.rs
diff --git a/compiler/rustc_mir/src/transform/coverage/spans.rs b/compiler/rustc_mir_transform/src/coverage/spans.rs
similarity index 99%
rename from compiler/rustc_mir/src/transform/coverage/spans.rs
rename to compiler/rustc_mir_transform/src/coverage/spans.rs
index 08cc87ccc349d..2ea2e06029d67 100644
--- a/compiler/rustc_mir/src/transform/coverage/spans.rs
+++ b/compiler/rustc_mir_transform/src/coverage/spans.rs
@@ -1,15 +1,13 @@
 use super::debug::term_type;
 use super::graph::{BasicCoverageBlock, BasicCoverageBlockData, CoverageGraph, START_BCB};
 
-use crate::util::spanview::source_range_no_file;
-
 use rustc_data_structures::graph::WithNumNodes;
+use rustc_middle::mir::spanview::source_range_no_file;
 use rustc_middle::mir::{
     self, AggregateKind, BasicBlock, FakeReadCause, Rvalue, Statement, StatementKind, Terminator,
     TerminatorKind,
 };
 use rustc_middle::ty::TyCtxt;
-
 use rustc_span::source_map::original_sp;
 use rustc_span::{BytePos, ExpnKind, MacroKind, Span, Symbol};
 
diff --git a/compiler/rustc_mir/src/transform/coverage/test_macros/Cargo.toml b/compiler/rustc_mir_transform/src/coverage/test_macros/Cargo.toml
similarity index 100%
rename from compiler/rustc_mir/src/transform/coverage/test_macros/Cargo.toml
rename to compiler/rustc_mir_transform/src/coverage/test_macros/Cargo.toml
diff --git a/compiler/rustc_mir/src/transform/coverage/test_macros/src/lib.rs b/compiler/rustc_mir_transform/src/coverage/test_macros/src/lib.rs
similarity index 100%
rename from compiler/rustc_mir/src/transform/coverage/test_macros/src/lib.rs
rename to compiler/rustc_mir_transform/src/coverage/test_macros/src/lib.rs
diff --git a/compiler/rustc_mir/src/transform/coverage/tests.rs b/compiler/rustc_mir_transform/src/coverage/tests.rs
similarity index 100%
rename from compiler/rustc_mir/src/transform/coverage/tests.rs
rename to compiler/rustc_mir_transform/src/coverage/tests.rs
diff --git a/compiler/rustc_mir/src/transform/deaggregator.rs b/compiler/rustc_mir_transform/src/deaggregator.rs
similarity index 98%
rename from compiler/rustc_mir/src/transform/deaggregator.rs
rename to compiler/rustc_mir_transform/src/deaggregator.rs
index 5bd7256c666c6..a5491f0ef4e2d 100644
--- a/compiler/rustc_mir/src/transform/deaggregator.rs
+++ b/compiler/rustc_mir_transform/src/deaggregator.rs
@@ -1,5 +1,5 @@
-use crate::transform::MirPass;
 use crate::util::expand_aggregate;
+use crate::MirPass;
 use rustc_middle::mir::*;
 use rustc_middle::ty::TyCtxt;
 
diff --git a/compiler/rustc_mir/src/transform/deduplicate_blocks.rs b/compiler/rustc_mir_transform/src/deduplicate_blocks.rs
similarity index 99%
rename from compiler/rustc_mir/src/transform/deduplicate_blocks.rs
rename to compiler/rustc_mir_transform/src/deduplicate_blocks.rs
index 912505c65983e..8d2413433a92b 100644
--- a/compiler/rustc_mir/src/transform/deduplicate_blocks.rs
+++ b/compiler/rustc_mir_transform/src/deduplicate_blocks.rs
@@ -3,7 +3,7 @@
 
 use std::{collections::hash_map::Entry, hash::Hash, hash::Hasher, iter};
 
-use crate::transform::MirPass;
+use crate::MirPass;
 
 use rustc_data_structures::fx::FxHashMap;
 use rustc_middle::mir::visit::MutVisitor;
diff --git a/compiler/rustc_mir/src/transform/dest_prop.rs b/compiler/rustc_mir_transform/src/dest_prop.rs
similarity index 99%
rename from compiler/rustc_mir/src/transform/dest_prop.rs
rename to compiler/rustc_mir_transform/src/dest_prop.rs
index 4f5a467a6ee62..dd95f00142309 100644
--- a/compiler/rustc_mir/src/transform/dest_prop.rs
+++ b/compiler/rustc_mir_transform/src/dest_prop.rs
@@ -96,12 +96,7 @@
 //! [previous attempt]: https://github.com/rust-lang/rust/pull/47954
 //! [subsequent approach]: https://github.com/rust-lang/rust/pull/71003
 
-use crate::dataflow::impls::{MaybeInitializedLocals, MaybeLiveLocals};
-use crate::dataflow::Analysis;
-use crate::{
-    transform::MirPass,
-    util::{dump_mir, PassWhere},
-};
+use crate::MirPass;
 use itertools::Itertools;
 use rustc_data_structures::unify::{InPlaceUnificationTable, UnifyKey};
 use rustc_index::{
@@ -110,11 +105,14 @@ use rustc_index::{
 };
 use rustc_middle::mir::tcx::PlaceTy;
 use rustc_middle::mir::visit::{MutVisitor, PlaceContext, Visitor};
+use rustc_middle::mir::{dump_mir, PassWhere};
 use rustc_middle::mir::{
     traversal, Body, InlineAsmOperand, Local, LocalKind, Location, Operand, Place, PlaceElem,
     Rvalue, Statement, StatementKind, Terminator, TerminatorKind,
 };
 use rustc_middle::ty::TyCtxt;
+use rustc_mir_dataflow::impls::{MaybeInitializedLocals, MaybeLiveLocals};
+use rustc_mir_dataflow::Analysis;
 
 // Empirical measurements have resulted in some observations:
 // - Running on a body with a single block and 500 locals takes barely any time
diff --git a/compiler/rustc_mir/src/transform/dump_mir.rs b/compiler/rustc_mir_transform/src/dump_mir.rs
similarity index 74%
rename from compiler/rustc_mir/src/transform/dump_mir.rs
rename to compiler/rustc_mir_transform/src/dump_mir.rs
index 5b6edf17d06ab..2a24e1ea8d7ed 100644
--- a/compiler/rustc_mir/src/transform/dump_mir.rs
+++ b/compiler/rustc_mir_transform/src/dump_mir.rs
@@ -5,9 +5,9 @@ use std::fmt;
 use std::fs::File;
 use std::io;
 
-use crate::transform::MirPass;
-use crate::util as mir_util;
+use crate::MirPass;
 use rustc_middle::mir::Body;
+use rustc_middle::mir::{dump_enabled, dump_mir, write_mir_pretty};
 use rustc_middle::ty::TyCtxt;
 use rustc_session::config::{OutputFilenames, OutputType};
 
@@ -39,21 +39,14 @@ pub fn on_mir_pass<'tcx>(
     body: &Body<'tcx>,
     is_after: bool,
 ) {
-    if mir_util::dump_enabled(tcx, pass_name, body.source.def_id()) {
-        mir_util::dump_mir(
-            tcx,
-            Some(pass_num),
-            pass_name,
-            &Disambiguator { is_after },
-            body,
-            |_, _| Ok(()),
-        );
+    if dump_enabled(tcx, pass_name, body.source.def_id()) {
+        dump_mir(tcx, Some(pass_num), pass_name, &Disambiguator { is_after }, body, |_, _| Ok(()));
     }
 }
 
 pub fn emit_mir(tcx: TyCtxt<'_>, outputs: &OutputFilenames) -> io::Result<()> {
     let path = outputs.path(OutputType::Mir);
     let mut f = io::BufWriter::new(File::create(&path)?);
-    mir_util::write_mir_pretty(tcx, None, &mut f)?;
+    write_mir_pretty(tcx, None, &mut f)?;
     Ok(())
 }
diff --git a/compiler/rustc_mir/src/transform/early_otherwise_branch.rs b/compiler/rustc_mir_transform/src/early_otherwise_branch.rs
similarity index 99%
rename from compiler/rustc_mir/src/transform/early_otherwise_branch.rs
rename to compiler/rustc_mir_transform/src/early_otherwise_branch.rs
index e507bcb0f812c..d7f1ad7f69643 100644
--- a/compiler/rustc_mir/src/transform/early_otherwise_branch.rs
+++ b/compiler/rustc_mir_transform/src/early_otherwise_branch.rs
@@ -1,4 +1,4 @@
-use crate::{transform::MirPass, util::patch::MirPatch};
+use rustc_middle::mir::patch::MirPatch;
 use rustc_middle::mir::*;
 use rustc_middle::ty::{Ty, TyCtxt};
 use std::fmt::Debug;
diff --git a/compiler/rustc_mir/src/transform/elaborate_drops.rs b/compiler/rustc_mir_transform/src/elaborate_drops.rs
similarity index 94%
rename from compiler/rustc_mir/src/transform/elaborate_drops.rs
rename to compiler/rustc_mir_transform/src/elaborate_drops.rs
index 9b44af06b7dee..b9a48197a351a 100644
--- a/compiler/rustc_mir/src/transform/elaborate_drops.rs
+++ b/compiler/rustc_mir_transform/src/elaborate_drops.rs
@@ -1,18 +1,17 @@
-use crate::dataflow;
-use crate::dataflow::impls::{MaybeInitializedPlaces, MaybeUninitializedPlaces};
-use crate::dataflow::move_paths::{LookupResult, MoveData, MovePathIndex};
-use crate::dataflow::on_lookup_result_bits;
-use crate::dataflow::MoveDataParamEnv;
-use crate::dataflow::{on_all_children_bits, on_all_drop_children_bits};
-use crate::dataflow::{Analysis, ResultsCursor};
-use crate::transform::MirPass;
-use crate::util::elaborate_drops::{elaborate_drop, DropFlagState, Unwind};
-use crate::util::elaborate_drops::{DropElaborator, DropFlagMode, DropStyle};
-use crate::util::patch::MirPatch;
+use crate::MirPass;
 use rustc_data_structures::fx::FxHashMap;
 use rustc_index::bit_set::BitSet;
+use rustc_middle::mir::patch::MirPatch;
 use rustc_middle::mir::*;
 use rustc_middle::ty::{self, TyCtxt};
+use rustc_mir_dataflow::elaborate_drops::{elaborate_drop, DropFlagState, Unwind};
+use rustc_mir_dataflow::elaborate_drops::{DropElaborator, DropFlagMode, DropStyle};
+use rustc_mir_dataflow::impls::{MaybeInitializedPlaces, MaybeUninitializedPlaces};
+use rustc_mir_dataflow::move_paths::{LookupResult, MoveData, MovePathIndex};
+use rustc_mir_dataflow::on_lookup_result_bits;
+use rustc_mir_dataflow::MoveDataParamEnv;
+use rustc_mir_dataflow::{on_all_children_bits, on_all_drop_children_bits};
+use rustc_mir_dataflow::{Analysis, ResultsCursor};
 use rustc_span::Span;
 use rustc_target::abi::VariantIdx;
 use std::fmt;
@@ -214,14 +213,14 @@ impl<'a, 'b, 'tcx> DropElaborator<'a, 'tcx> for Elaborator<'a, 'b, 'tcx> {
     }
 
     fn field_subpath(&self, path: Self::Path, field: Field) -> Option<Self::Path> {
-        dataflow::move_path_children_matching(self.ctxt.move_data(), path, |e| match e {
+        rustc_mir_dataflow::move_path_children_matching(self.ctxt.move_data(), path, |e| match e {
             ProjectionElem::Field(idx, _) => idx == field,
             _ => false,
         })
     }
 
     fn array_subpath(&self, path: Self::Path, index: u64, size: u64) -> Option<Self::Path> {
-        dataflow::move_path_children_matching(self.ctxt.move_data(), path, |e| match e {
+        rustc_mir_dataflow::move_path_children_matching(self.ctxt.move_data(), path, |e| match e {
             ProjectionElem::ConstantIndex { offset, min_length, from_end } => {
                 debug_assert!(size == min_length, "min_length should be exact for arrays");
                 assert!(!from_end, "from_end should not be used for array element ConstantIndex");
@@ -232,13 +231,13 @@ impl<'a, 'b, 'tcx> DropElaborator<'a, 'tcx> for Elaborator<'a, 'b, 'tcx> {
     }
 
     fn deref_subpath(&self, path: Self::Path) -> Option<Self::Path> {
-        dataflow::move_path_children_matching(self.ctxt.move_data(), path, |e| {
+        rustc_mir_dataflow::move_path_children_matching(self.ctxt.move_data(), path, |e| {
             e == ProjectionElem::Deref
         })
     }
 
     fn downcast_subpath(&self, path: Self::Path, variant: VariantIdx) -> Option<Self::Path> {
-        dataflow::move_path_children_matching(self.ctxt.move_data(), path, |e| match e {
+        rustc_mir_dataflow::move_path_children_matching(self.ctxt.move_data(), path, |e| match e {
             ProjectionElem::Downcast(_, idx) => idx == variant,
             _ => false,
         })
@@ -513,9 +512,14 @@ impl<'b, 'tcx> ElaborateDropsCtxt<'b, 'tcx> {
 
     fn drop_flags_for_args(&mut self) {
         let loc = Location::START;
-        dataflow::drop_flag_effects_for_function_entry(self.tcx, self.body, self.env, |path, ds| {
-            self.set_drop_flag(loc, path, ds);
-        })
+        rustc_mir_dataflow::drop_flag_effects_for_function_entry(
+            self.tcx,
+            self.body,
+            self.env,
+            |path, ds| {
+                self.set_drop_flag(loc, path, ds);
+            },
+        )
     }
 
     fn drop_flags_for_locs(&mut self) {
@@ -556,7 +560,7 @@ impl<'b, 'tcx> ElaborateDropsCtxt<'b, 'tcx> {
                     }
                 }
                 let loc = Location { block: bb, statement_index: i };
-                dataflow::drop_flag_effects_for_location(
+                rustc_mir_dataflow::drop_flag_effects_for_location(
                     self.tcx,
                     self.body,
                     self.env,
diff --git a/compiler/rustc_mir/src/transform/function_item_references.rs b/compiler/rustc_mir_transform/src/function_item_references.rs
similarity index 99%
rename from compiler/rustc_mir/src/transform/function_item_references.rs
rename to compiler/rustc_mir_transform/src/function_item_references.rs
index ba2c91a9347ec..d96a067fdda79 100644
--- a/compiler/rustc_mir/src/transform/function_item_references.rs
+++ b/compiler/rustc_mir_transform/src/function_item_references.rs
@@ -11,7 +11,7 @@ use rustc_session::lint::builtin::FUNCTION_ITEM_REFERENCES;
 use rustc_span::{symbol::sym, Span};
 use rustc_target::spec::abi::Abi;
 
-use crate::transform::MirPass;
+use crate::MirPass;
 
 pub struct FunctionItemReferences;
 
diff --git a/compiler/rustc_mir/src/transform/generator.rs b/compiler/rustc_mir_transform/src/generator.rs
similarity index 98%
rename from compiler/rustc_mir/src/transform/generator.rs
rename to compiler/rustc_mir_transform/src/generator.rs
index acdaa5b456857..06366b6fc31d5 100644
--- a/compiler/rustc_mir/src/transform/generator.rs
+++ b/compiler/rustc_mir_transform/src/generator.rs
@@ -49,25 +49,25 @@
 //! For generators with state 1 (returned) and state 2 (poisoned) it does nothing.
 //! Otherwise it drops all the values in scope at the last suspension point.
 
-use crate::dataflow::impls::{
-    MaybeBorrowedLocals, MaybeLiveLocals, MaybeRequiresStorage, MaybeStorageLive,
-};
-use crate::dataflow::{self, Analysis};
-use crate::transform::simplify;
-use crate::transform::MirPass;
-use crate::util::dump_mir;
+use crate::simplify;
 use crate::util::expand_aggregate;
-use crate::util::storage;
+use crate::MirPass;
 use rustc_data_structures::fx::FxHashMap;
 use rustc_hir as hir;
 use rustc_hir::lang_items::LangItem;
 use rustc_index::bit_set::{BitMatrix, BitSet};
 use rustc_index::vec::{Idx, IndexVec};
+use rustc_middle::mir::dump_mir;
 use rustc_middle::mir::visit::{MutVisitor, PlaceContext, Visitor};
 use rustc_middle::mir::*;
 use rustc_middle::ty::subst::{Subst, SubstsRef};
 use rustc_middle::ty::GeneratorSubsts;
 use rustc_middle::ty::{self, AdtDef, Ty, TyCtxt};
+use rustc_mir_dataflow::impls::{
+    MaybeBorrowedLocals, MaybeLiveLocals, MaybeRequiresStorage, MaybeStorageLive,
+};
+use rustc_mir_dataflow::storage;
+use rustc_mir_dataflow::{self, Analysis};
 use rustc_target::abi::VariantIdx;
 use rustc_target::spec::PanicStrategy;
 use std::{iter, ops};
@@ -468,7 +468,7 @@ fn locals_live_across_suspend_points(
         .iterate_to_fixpoint();
 
     let mut borrowed_locals_cursor =
-        dataflow::ResultsCursor::new(body_ref, &borrowed_locals_results);
+        rustc_mir_dataflow::ResultsCursor::new(body_ref, &borrowed_locals_results);
 
     // Calculate the MIR locals that we actually need to keep storage around
     // for.
@@ -476,7 +476,7 @@ fn locals_live_across_suspend_points(
         .into_engine(tcx, body_ref)
         .iterate_to_fixpoint();
     let mut requires_storage_cursor =
-        dataflow::ResultsCursor::new(body_ref, &requires_storage_results);
+        rustc_mir_dataflow::ResultsCursor::new(body_ref, &requires_storage_results);
 
     // Calculate the liveness of MIR locals ignoring borrows.
     let mut liveness = MaybeLiveLocals
@@ -616,7 +616,7 @@ fn compute_storage_conflicts(
     body: &'mir Body<'tcx>,
     saved_locals: &GeneratorSavedLocals,
     always_live_locals: storage::AlwaysLiveLocals,
-    requires_storage: dataflow::Results<'tcx, MaybeRequiresStorage<'mir, 'tcx>>,
+    requires_storage: rustc_mir_dataflow::Results<'tcx, MaybeRequiresStorage<'mir, 'tcx>>,
 ) -> BitMatrix<GeneratorSavedLocal, GeneratorSavedLocal> {
     assert_eq!(body.local_decls.len(), saved_locals.domain_size());
 
@@ -671,7 +671,7 @@ struct StorageConflictVisitor<'mir, 'tcx, 's> {
     local_conflicts: BitMatrix<Local, Local>,
 }
 
-impl dataflow::ResultsVisitor<'mir, 'tcx> for StorageConflictVisitor<'mir, 'tcx, '_> {
+impl rustc_mir_dataflow::ResultsVisitor<'mir, 'tcx> for StorageConflictVisitor<'mir, 'tcx, '_> {
     type FlowState = BitSet<Local>;
 
     fn visit_statement_before_primary_effect(
@@ -865,8 +865,8 @@ fn insert_switch<'tcx>(
 
 fn elaborate_generator_drops<'tcx>(tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) {
     use crate::shim::DropShimElaborator;
-    use crate::util::elaborate_drops::{elaborate_drop, Unwind};
-    use crate::util::patch::MirPatch;
+    use rustc_middle::mir::patch::MirPatch;
+    use rustc_mir_dataflow::elaborate_drops::{elaborate_drop, Unwind};
 
     // Note that `elaborate_drops` only drops the upvars of a generator, and
     // this is ok because `open_drop` can only be reached within that own
diff --git a/compiler/rustc_mir/src/transform/inline.rs b/compiler/rustc_mir_transform/src/inline.rs
similarity index 99%
rename from compiler/rustc_mir/src/transform/inline.rs
rename to compiler/rustc_mir_transform/src/inline.rs
index 8e9da31eba11f..d43528a1cf098 100644
--- a/compiler/rustc_mir/src/transform/inline.rs
+++ b/compiler/rustc_mir_transform/src/inline.rs
@@ -13,7 +13,7 @@ use rustc_span::{hygiene::ExpnKind, ExpnData, Span};
 use rustc_target::spec::abi::Abi;
 
 use super::simplify::{remove_dead_blocks, CfgSimplifier};
-use crate::transform::MirPass;
+use crate::MirPass;
 use std::iter;
 use std::ops::{Range, RangeFrom};
 
diff --git a/compiler/rustc_mir/src/transform/inline/cycle.rs b/compiler/rustc_mir_transform/src/inline/cycle.rs
similarity index 100%
rename from compiler/rustc_mir/src/transform/inline/cycle.rs
rename to compiler/rustc_mir_transform/src/inline/cycle.rs
diff --git a/compiler/rustc_mir/src/transform/instcombine.rs b/compiler/rustc_mir_transform/src/instcombine.rs
similarity index 99%
rename from compiler/rustc_mir/src/transform/instcombine.rs
rename to compiler/rustc_mir_transform/src/instcombine.rs
index 805f546104cae..e15a69c95ae9c 100644
--- a/compiler/rustc_mir/src/transform/instcombine.rs
+++ b/compiler/rustc_mir_transform/src/instcombine.rs
@@ -1,6 +1,6 @@
 //! Performs various peephole optimizations.
 
-use crate::transform::MirPass;
+use crate::MirPass;
 use rustc_hir::Mutability;
 use rustc_middle::mir::{
     BinOp, Body, Constant, LocalDecls, Operand, Place, ProjectionElem, Rvalue, SourceInfo,
diff --git a/compiler/rustc_mir/src/transform/mod.rs b/compiler/rustc_mir_transform/src/lib.rs
similarity index 91%
rename from compiler/rustc_mir/src/transform/mod.rs
rename to compiler/rustc_mir_transform/src/lib.rs
index d4c2456e9a436..22abce65a4b7d 100644
--- a/compiler/rustc_mir/src/transform/mod.rs
+++ b/compiler/rustc_mir_transform/src/lib.rs
@@ -1,5 +1,26 @@
-use crate::{shim, util};
+#![cfg_attr(bootstrap, feature(bindings_after_at))]
+#![feature(box_patterns)]
+#![feature(box_syntax)]
+#![feature(crate_visibility_modifier)]
+#![feature(const_panic)]
+#![feature(in_band_lifetimes)]
+#![feature(iter_zip)]
+#![feature(map_try_insert)]
+#![feature(min_specialization)]
+#![feature(option_get_or_insert_default)]
+#![feature(once_cell)]
+#![feature(never_type)]
+#![feature(trusted_step)]
+#![feature(try_blocks)]
+#![recursion_limit = "256"]
+
+#[macro_use]
+extern crate tracing;
+#[macro_use]
+extern crate rustc_middle;
+
 use required_consts::RequiredConstsVisitor;
+use rustc_const_eval::util;
 use rustc_data_structures::fx::FxHashSet;
 use rustc_data_structures::steal::Steal;
 use rustc_hir as hir;
@@ -11,57 +32,59 @@ use rustc_middle::mir::{traversal, Body, ConstQualifs, MirPhase, Promoted};
 use rustc_middle::ty::query::Providers;
 use rustc_middle::ty::{self, TyCtxt, TypeFoldable};
 use rustc_span::{Span, Symbol};
-use std::borrow::Cow;
-
-pub mod abort_unwinding_calls;
-pub mod add_call_guards;
-pub mod add_moves_for_packed_drops;
-pub mod add_retag;
-pub mod check_const_item_mutation;
-pub mod check_consts;
-pub mod check_packed_ref;
+
+mod abort_unwinding_calls;
+mod add_call_guards;
+mod add_moves_for_packed_drops;
+mod add_retag;
+mod check_const_item_mutation;
+mod check_packed_ref;
 pub mod check_unsafety;
-pub mod cleanup_post_borrowck;
-pub mod const_debuginfo;
-pub mod const_goto;
-pub mod const_prop;
-pub mod coverage;
-pub mod deaggregator;
-pub mod deduplicate_blocks;
-pub mod dest_prop;
+mod cleanup_post_borrowck;
+mod const_debuginfo;
+mod const_goto;
+mod const_prop;
+mod coverage;
+mod deaggregator;
+mod deduplicate_blocks;
+mod dest_prop;
 pub mod dump_mir;
-pub mod early_otherwise_branch;
-pub mod elaborate_drops;
-pub mod function_item_references;
-pub mod generator;
-pub mod inline;
-pub mod instcombine;
-pub mod lower_intrinsics;
-pub mod lower_slice_len;
-pub mod match_branches;
-pub mod multiple_return_terminators;
-pub mod nrvo;
-pub mod promote_consts;
-pub mod remove_noop_landing_pads;
-pub mod remove_storage_markers;
-pub mod remove_unneeded_drops;
-pub mod remove_zsts;
-pub mod required_consts;
-pub mod rustc_peek;
-pub mod separate_const_switch;
-pub mod simplify;
-pub mod simplify_branches;
-pub mod simplify_comparison_integral;
-pub mod simplify_try;
-pub mod uninhabited_enum_branching;
-pub mod unreachable_prop;
-pub mod validate;
-
-pub use rustc_middle::mir::MirSource;
-
-pub(crate) fn provide(providers: &mut Providers) {
-    self::check_unsafety::provide(providers);
-    self::check_packed_ref::provide(providers);
+mod early_otherwise_branch;
+mod elaborate_drops;
+mod function_item_references;
+mod generator;
+mod inline;
+mod instcombine;
+mod lower_intrinsics;
+mod lower_slice_len;
+mod match_branches;
+mod multiple_return_terminators;
+mod nrvo;
+mod remove_noop_landing_pads;
+mod remove_storage_markers;
+mod remove_unneeded_drops;
+mod remove_zsts;
+mod required_consts;
+mod separate_const_switch;
+mod shim;
+mod simplify;
+mod simplify_branches;
+mod simplify_comparison_integral;
+mod simplify_try;
+mod uninhabited_enum_branching;
+mod unreachable_prop;
+
+use rustc_const_eval::transform::check_consts;
+use rustc_const_eval::transform::promote_consts;
+use rustc_const_eval::transform::validate;
+use rustc_const_eval::transform::MirPass;
+use rustc_mir_dataflow::rustc_peek;
+
+pub fn provide(providers: &mut Providers) {
+    check_unsafety::provide(providers);
+    check_packed_ref::provide(providers);
+    coverage::query::provide(providers);
+    shim::provide(providers);
     *providers = Providers {
         mir_keys,
         mir_const,
@@ -83,6 +106,8 @@ pub(crate) fn provide(providers: &mut Providers) {
         optimized_mir,
         is_mir_available,
         is_ctfe_mir_available: |tcx, did| is_mir_available(tcx, did),
+        mir_callgraph_reachable: inline::cycle::mir_callgraph_reachable,
+        mir_inliner_callees: inline::cycle::mir_inliner_callees,
         promoted_mir: |tcx, def_id| {
             let def_id = def_id.expect_local();
             if let Some(def) = ty::WithOptConstParam::try_lookup(def_id, tcx) {
@@ -96,7 +121,6 @@ pub(crate) fn provide(providers: &mut Providers) {
         },
         ..*providers
     };
-    coverage::query::provide(providers);
 }
 
 fn is_mir_available(tcx: TyCtxt<'_>, def_id: DefId) -> bool {
@@ -144,25 +168,7 @@ fn mir_keys(tcx: TyCtxt<'_>, (): ()) -> FxHashSet<LocalDefId> {
     set
 }
 
-/// Generates a default name for the pass based on the name of the
-/// type `T`.
-pub fn default_name<T: ?Sized>() -> Cow<'static, str> {
-    let name = std::any::type_name::<T>();
-    if let Some(tail) = name.rfind(':') { Cow::from(&name[tail + 1..]) } else { Cow::from(name) }
-}
-
-/// A streamlined trait that you can implement to create a pass; the
-/// pass will be named after the type, and it will consist of a main
-/// loop that goes over each available MIR and applies `run_pass`.
-pub trait MirPass<'tcx> {
-    fn name(&self) -> Cow<'_, str> {
-        default_name::<Self>()
-    }
-
-    fn run_pass(&self, tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>);
-}
-
-pub fn run_passes(
+fn run_passes(
     tcx: TyCtxt<'tcx>,
     body: &mut Body<'tcx>,
     mir_phase: MirPhase,
@@ -269,7 +275,7 @@ fn mir_const<'tcx>(
 
     let mut body = tcx.mir_built(def).steal();
 
-    util::dump_mir(tcx, None, "mir_map", &0, &body, |_, _| Ok(()));
+    rustc_middle::mir::dump_mir(tcx, None, "mir_map", &0, &body, |_, _| Ok(()));
 
     run_passes(
         tcx,
diff --git a/compiler/rustc_mir/src/transform/lower_intrinsics.rs b/compiler/rustc_mir_transform/src/lower_intrinsics.rs
similarity index 99%
rename from compiler/rustc_mir/src/transform/lower_intrinsics.rs
rename to compiler/rustc_mir_transform/src/lower_intrinsics.rs
index e9f1d4f2ce827..2f89b041c27b1 100644
--- a/compiler/rustc_mir/src/transform/lower_intrinsics.rs
+++ b/compiler/rustc_mir_transform/src/lower_intrinsics.rs
@@ -1,6 +1,6 @@
 //! Lowers intrinsic calls
 
-use crate::transform::MirPass;
+use crate::MirPass;
 use rustc_middle::mir::*;
 use rustc_middle::ty::subst::SubstsRef;
 use rustc_middle::ty::{self, Ty, TyCtxt};
diff --git a/compiler/rustc_mir/src/transform/lower_slice_len.rs b/compiler/rustc_mir_transform/src/lower_slice_len.rs
similarity index 99%
rename from compiler/rustc_mir/src/transform/lower_slice_len.rs
rename to compiler/rustc_mir_transform/src/lower_slice_len.rs
index c3eb2d9f921b3..30de374a2d822 100644
--- a/compiler/rustc_mir/src/transform/lower_slice_len.rs
+++ b/compiler/rustc_mir_transform/src/lower_slice_len.rs
@@ -1,7 +1,7 @@
 //! This pass lowers calls to core::slice::len to just Len op.
 //! It should run before inlining!
 
-use crate::transform::MirPass;
+use crate::MirPass;
 use rustc_hir::def_id::DefId;
 use rustc_index::vec::IndexVec;
 use rustc_middle::mir::*;
diff --git a/compiler/rustc_mir/src/transform/match_branches.rs b/compiler/rustc_mir_transform/src/match_branches.rs
similarity index 98%
rename from compiler/rustc_mir/src/transform/match_branches.rs
rename to compiler/rustc_mir_transform/src/match_branches.rs
index 37a3fa50a52dd..c618abe9d0599 100644
--- a/compiler/rustc_mir/src/transform/match_branches.rs
+++ b/compiler/rustc_mir_transform/src/match_branches.rs
@@ -1,4 +1,4 @@
-use crate::transform::MirPass;
+use crate::MirPass;
 use rustc_middle::mir::*;
 use rustc_middle::ty::TyCtxt;
 use std::iter;
@@ -134,7 +134,7 @@ impl<'tcx> MirPass<'tcx> for MatchBranchSimplification {
                             let const_cmp = Operand::const_from_scalar(
                                 tcx,
                                 switch_ty,
-                                crate::interpret::Scalar::from_uint(val, size),
+                                rustc_const_eval::interpret::Scalar::from_uint(val, size),
                                 rustc_span::DUMMY_SP,
                             );
                             let op = if f_b { BinOp::Eq } else { BinOp::Ne };
diff --git a/compiler/rustc_mir/src/transform/multiple_return_terminators.rs b/compiler/rustc_mir_transform/src/multiple_return_terminators.rs
similarity index 96%
rename from compiler/rustc_mir/src/transform/multiple_return_terminators.rs
rename to compiler/rustc_mir_transform/src/multiple_return_terminators.rs
index cd2db18055286..b614917a88369 100644
--- a/compiler/rustc_mir/src/transform/multiple_return_terminators.rs
+++ b/compiler/rustc_mir_transform/src/multiple_return_terminators.rs
@@ -1,7 +1,7 @@
 //! This pass removes jumps to basic blocks containing only a return, and replaces them with a
 //! return instead.
 
-use crate::transform::{simplify, MirPass};
+use crate::{simplify, MirPass};
 use rustc_index::bit_set::BitSet;
 use rustc_middle::mir::*;
 use rustc_middle::ty::TyCtxt;
diff --git a/compiler/rustc_mir/src/transform/nrvo.rs b/compiler/rustc_mir_transform/src/nrvo.rs
similarity index 99%
rename from compiler/rustc_mir/src/transform/nrvo.rs
rename to compiler/rustc_mir_transform/src/nrvo.rs
index 445dc12909c14..3ac4e77cf9a75 100644
--- a/compiler/rustc_mir/src/transform/nrvo.rs
+++ b/compiler/rustc_mir_transform/src/nrvo.rs
@@ -6,7 +6,7 @@ use rustc_middle::mir::visit::{MutVisitor, NonUseContext, PlaceContext, Visitor}
 use rustc_middle::mir::{self, BasicBlock, Local, Location};
 use rustc_middle::ty::TyCtxt;
 
-use crate::transform::MirPass;
+use crate::MirPass;
 
 /// This pass looks for MIR that always copies the same local into the return place and eliminates
 /// the copy by renaming all uses of that local to `_0`.
diff --git a/compiler/rustc_mir/src/transform/remove_noop_landing_pads.rs b/compiler/rustc_mir_transform/src/remove_noop_landing_pads.rs
similarity index 98%
rename from compiler/rustc_mir/src/transform/remove_noop_landing_pads.rs
rename to compiler/rustc_mir_transform/src/remove_noop_landing_pads.rs
index 5347846a4b334..298bcd9dc24f9 100644
--- a/compiler/rustc_mir/src/transform/remove_noop_landing_pads.rs
+++ b/compiler/rustc_mir_transform/src/remove_noop_landing_pads.rs
@@ -1,6 +1,6 @@
-use crate::transform::MirPass;
-use crate::util::patch::MirPatch;
+use crate::MirPass;
 use rustc_index::bit_set::BitSet;
+use rustc_middle::mir::patch::MirPatch;
 use rustc_middle::mir::*;
 use rustc_middle::ty::TyCtxt;
 use rustc_target::spec::PanicStrategy;
diff --git a/compiler/rustc_mir/src/transform/remove_storage_markers.rs b/compiler/rustc_mir_transform/src/remove_storage_markers.rs
similarity index 96%
rename from compiler/rustc_mir/src/transform/remove_storage_markers.rs
rename to compiler/rustc_mir_transform/src/remove_storage_markers.rs
index 2d529feb072f9..0c7323cbac5b1 100644
--- a/compiler/rustc_mir/src/transform/remove_storage_markers.rs
+++ b/compiler/rustc_mir_transform/src/remove_storage_markers.rs
@@ -1,6 +1,6 @@
 //! This pass removes storage markers if they won't be emitted during codegen.
 
-use crate::transform::MirPass;
+use crate::MirPass;
 use rustc_middle::mir::*;
 use rustc_middle::ty::TyCtxt;
 
diff --git a/compiler/rustc_mir/src/transform/remove_unneeded_drops.rs b/compiler/rustc_mir_transform/src/remove_unneeded_drops.rs
similarity index 97%
rename from compiler/rustc_mir/src/transform/remove_unneeded_drops.rs
rename to compiler/rustc_mir_transform/src/remove_unneeded_drops.rs
index 02e45021a0aaf..5c9d04a08bfec 100644
--- a/compiler/rustc_mir/src/transform/remove_unneeded_drops.rs
+++ b/compiler/rustc_mir_transform/src/remove_unneeded_drops.rs
@@ -1,6 +1,6 @@
 //! This pass replaces a drop of a type that does not need dropping, with a goto
 
-use crate::transform::MirPass;
+use crate::MirPass;
 use rustc_middle::mir::*;
 use rustc_middle::ty::TyCtxt;
 
diff --git a/compiler/rustc_mir/src/transform/remove_zsts.rs b/compiler/rustc_mir_transform/src/remove_zsts.rs
similarity index 98%
rename from compiler/rustc_mir/src/transform/remove_zsts.rs
rename to compiler/rustc_mir_transform/src/remove_zsts.rs
index 03277b1b2e0be..25e3c52132cca 100644
--- a/compiler/rustc_mir/src/transform/remove_zsts.rs
+++ b/compiler/rustc_mir_transform/src/remove_zsts.rs
@@ -1,6 +1,6 @@
 //! Removes assignments to ZST places.
 
-use crate::transform::MirPass;
+use crate::MirPass;
 use rustc_middle::mir::tcx::PlaceTy;
 use rustc_middle::mir::{Body, LocalDecls, Place, StatementKind};
 use rustc_middle::ty::{self, Ty, TyCtxt};
diff --git a/compiler/rustc_mir/src/transform/required_consts.rs b/compiler/rustc_mir_transform/src/required_consts.rs
similarity index 100%
rename from compiler/rustc_mir/src/transform/required_consts.rs
rename to compiler/rustc_mir_transform/src/required_consts.rs
diff --git a/compiler/rustc_mir/src/transform/separate_const_switch.rs b/compiler/rustc_mir_transform/src/separate_const_switch.rs
similarity index 99%
rename from compiler/rustc_mir/src/transform/separate_const_switch.rs
rename to compiler/rustc_mir_transform/src/separate_const_switch.rs
index 87cd27984a073..1945e551485d8 100644
--- a/compiler/rustc_mir/src/transform/separate_const_switch.rs
+++ b/compiler/rustc_mir_transform/src/separate_const_switch.rs
@@ -37,7 +37,7 @@
 //! simplicity rather than completeness (it notably
 //! sometimes duplicates abusively).
 
-use crate::transform::MirPass;
+use crate::MirPass;
 use rustc_middle::mir::*;
 use rustc_middle::ty::TyCtxt;
 use smallvec::SmallVec;
diff --git a/compiler/rustc_mir/src/shim.rs b/compiler/rustc_mir_transform/src/shim.rs
similarity index 99%
rename from compiler/rustc_mir/src/shim.rs
rename to compiler/rustc_mir_transform/src/shim.rs
index 8083ec954478a..4d350fc87cb3a 100644
--- a/compiler/rustc_mir/src/shim.rs
+++ b/compiler/rustc_mir_transform/src/shim.rs
@@ -15,13 +15,13 @@ use rustc_target::spec::abi::Abi;
 use std::fmt;
 use std::iter;
 
-use crate::transform::{
+use crate::util::expand_aggregate;
+use crate::{
     abort_unwinding_calls, add_call_guards, add_moves_for_packed_drops, remove_noop_landing_pads,
     run_passes, simplify,
 };
-use crate::util::elaborate_drops::{self, DropElaborator, DropFlagMode, DropStyle};
-use crate::util::expand_aggregate;
-use crate::util::patch::MirPatch;
+use rustc_middle::mir::patch::MirPatch;
+use rustc_mir_dataflow::elaborate_drops::{self, DropElaborator, DropFlagMode, DropStyle};
 
 pub fn provide(providers: &mut Providers) {
     providers.mir_shims = make_shim;
@@ -940,7 +940,7 @@ pub fn build_adt_ctor(tcx: TyCtxt<'_>, ctor_id: DefId) -> Body<'_> {
         span,
     );
 
-    crate::util::dump_mir(tcx, None, "mir_map", &0, &body, |_, _| Ok(()));
+    rustc_middle::mir::dump_mir(tcx, None, "mir_map", &0, &body, |_, _| Ok(()));
 
     body
 }
diff --git a/compiler/rustc_mir/src/transform/simplify.rs b/compiler/rustc_mir_transform/src/simplify.rs
similarity index 99%
rename from compiler/rustc_mir/src/transform/simplify.rs
rename to compiler/rustc_mir_transform/src/simplify.rs
index 3ecb5133e3b48..e3cfd1d0afcd7 100644
--- a/compiler/rustc_mir/src/transform/simplify.rs
+++ b/compiler/rustc_mir_transform/src/simplify.rs
@@ -27,7 +27,7 @@
 //! naively generate still contains the `_a = ()` write in the unreachable block "after" the
 //! return.
 
-use crate::transform::MirPass;
+use crate::MirPass;
 use rustc_index::vec::{Idx, IndexVec};
 use rustc_middle::mir::coverage::*;
 use rustc_middle::mir::visit::{MutVisitor, MutatingUseContext, PlaceContext, Visitor};
diff --git a/compiler/rustc_mir/src/transform/simplify_branches.rs b/compiler/rustc_mir_transform/src/simplify_branches.rs
similarity index 98%
rename from compiler/rustc_mir/src/transform/simplify_branches.rs
rename to compiler/rustc_mir_transform/src/simplify_branches.rs
index a9a45e61a38cb..df90cfa318df0 100644
--- a/compiler/rustc_mir/src/transform/simplify_branches.rs
+++ b/compiler/rustc_mir_transform/src/simplify_branches.rs
@@ -1,6 +1,6 @@
 //! A pass that simplifies branches when their condition is known.
 
-use crate::transform::MirPass;
+use crate::MirPass;
 use rustc_middle::mir::*;
 use rustc_middle::ty::TyCtxt;
 
diff --git a/compiler/rustc_mir/src/transform/simplify_comparison_integral.rs b/compiler/rustc_mir_transform/src/simplify_comparison_integral.rs
similarity index 100%
rename from compiler/rustc_mir/src/transform/simplify_comparison_integral.rs
rename to compiler/rustc_mir_transform/src/simplify_comparison_integral.rs
diff --git a/compiler/rustc_mir/src/transform/simplify_try.rs b/compiler/rustc_mir_transform/src/simplify_try.rs
similarity index 99%
rename from compiler/rustc_mir/src/transform/simplify_try.rs
rename to compiler/rustc_mir_transform/src/simplify_try.rs
index 7c35dab694f3c..fd36671b36f54 100644
--- a/compiler/rustc_mir/src/transform/simplify_try.rs
+++ b/compiler/rustc_mir_transform/src/simplify_try.rs
@@ -9,7 +9,7 @@
 //!
 //! into just `x`.
 
-use crate::transform::{simplify, MirPass};
+use crate::{simplify, MirPass};
 use itertools::Itertools as _;
 use rustc_index::{bit_set::BitSet, vec::IndexVec};
 use rustc_middle::mir::visit::{NonUseContext, PlaceContext, Visitor};
diff --git a/compiler/rustc_mir/src/transform/uninhabited_enum_branching.rs b/compiler/rustc_mir_transform/src/uninhabited_enum_branching.rs
similarity index 99%
rename from compiler/rustc_mir/src/transform/uninhabited_enum_branching.rs
rename to compiler/rustc_mir_transform/src/uninhabited_enum_branching.rs
index 5c6c158d46e3a..5cef64d7786b3 100644
--- a/compiler/rustc_mir/src/transform/uninhabited_enum_branching.rs
+++ b/compiler/rustc_mir_transform/src/uninhabited_enum_branching.rs
@@ -1,6 +1,6 @@
 //! A pass that eliminates branches on uninhabited enum variants.
 
-use crate::transform::MirPass;
+use crate::MirPass;
 use rustc_data_structures::stable_set::FxHashSet;
 use rustc_middle::mir::{
     BasicBlock, BasicBlockData, Body, Local, Operand, Rvalue, StatementKind, SwitchTargets,
diff --git a/compiler/rustc_mir/src/transform/unreachable_prop.rs b/compiler/rustc_mir_transform/src/unreachable_prop.rs
similarity index 98%
rename from compiler/rustc_mir/src/transform/unreachable_prop.rs
rename to compiler/rustc_mir_transform/src/unreachable_prop.rs
index e7fb6b4f6b4ad..baf381081ddab 100644
--- a/compiler/rustc_mir/src/transform/unreachable_prop.rs
+++ b/compiler/rustc_mir_transform/src/unreachable_prop.rs
@@ -2,8 +2,8 @@
 //! when all of their successors are unreachable. This is achieved through a
 //! post-order traversal of the blocks.
 
-use crate::transform::simplify;
-use crate::transform::MirPass;
+use crate::simplify;
+use crate::MirPass;
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_middle::mir::*;
 use rustc_middle::ty::TyCtxt;
diff --git a/compiler/rustc_monomorphize/Cargo.toml b/compiler/rustc_monomorphize/Cargo.toml
new file mode 100644
index 0000000000000..350ae08877718
--- /dev/null
+++ b/compiler/rustc_monomorphize/Cargo.toml
@@ -0,0 +1,19 @@
+[package]
+name = "rustc_monomorphize"
+version = "0.0.0"
+edition = "2018"
+
+[lib]
+doctest = false
+
+[dependencies]
+smallvec = { version = "1.6.1", features = ["union", "may_dangle"] }
+tracing = "0.1"
+rustc_data_structures = { path = "../rustc_data_structures" }
+rustc_errors = { path = "../rustc_errors" }
+rustc_hir = { path = "../rustc_hir" }
+rustc_index = { path = "../rustc_index" }
+rustc_middle = { path = "../rustc_middle" }
+rustc_session = { path = "../rustc_session" }
+rustc_span = { path = "../rustc_span" }
+rustc_target = { path = "../rustc_target" }
diff --git a/compiler/rustc_mir/src/monomorphize/collector.rs b/compiler/rustc_monomorphize/src/collector.rs
similarity index 99%
rename from compiler/rustc_mir/src/monomorphize/collector.rs
rename to compiler/rustc_monomorphize/src/collector.rs
index 4cb362238c1c5..1e39b1bd5e80e 100644
--- a/compiler/rustc_mir/src/monomorphize/collector.rs
+++ b/compiler/rustc_monomorphize/src/collector.rs
@@ -178,8 +178,6 @@
 //! this is not implemented however: a mono item will be produced
 //! regardless of whether it is actually needed or not.
 
-use crate::monomorphize;
-
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_data_structures::sync::{par_iter, MTLock, MTRef, ParallelIterator};
 use rustc_errors::{ErrorReported, FatalError};
@@ -1052,7 +1050,7 @@ fn find_vtable_types_for_unsizing<'tcx>(
             assert_eq!(source_adt_def, target_adt_def);
 
             let CustomCoerceUnsized::Struct(coerce_index) =
-                monomorphize::custom_coerce_unsize_info(tcx, source_ty, target_ty);
+                crate::custom_coerce_unsize_info(tcx, source_ty, target_ty);
 
             let source_fields = &source_adt_def.non_enum_variant().fields;
             let target_fields = &target_adt_def.non_enum_variant().fields;
@@ -1085,7 +1083,7 @@ fn create_fn_mono_item<'tcx>(
     let def_id = instance.def_id();
     if tcx.sess.opts.debugging_opts.profile_closures && def_id.is_local() && tcx.is_closure(def_id)
     {
-        monomorphize::util::dump_closure_profile(tcx, instance);
+        crate::util::dump_closure_profile(tcx, instance);
     }
 
     respan(source, MonoItem::Fn(instance.polymorphize(tcx)))
diff --git a/compiler/rustc_mir/src/monomorphize/mod.rs b/compiler/rustc_monomorphize/src/lib.rs
similarity index 65%
rename from compiler/rustc_mir/src/monomorphize/mod.rs
rename to compiler/rustc_monomorphize/src/lib.rs
index 57d2723cf9cfd..08b1d7b7fabd7 100644
--- a/compiler/rustc_mir/src/monomorphize/mod.rs
+++ b/compiler/rustc_monomorphize/src/lib.rs
@@ -1,13 +1,25 @@
+#![feature(array_windows)]
+#![feature(bool_to_option)]
+#![feature(crate_visibility_modifier)]
+#![feature(control_flow_enum)]
+#![feature(in_band_lifetimes)]
+#![recursion_limit = "256"]
+
+#[macro_use]
+extern crate tracing;
+#[macro_use]
+extern crate rustc_middle;
+
+use rustc_hir::lang_items::LangItem;
 use rustc_middle::traits;
 use rustc_middle::ty::adjustment::CustomCoerceUnsized;
+use rustc_middle::ty::query::Providers;
 use rustc_middle::ty::{self, Ty, TyCtxt};
 
-use rustc_hir::lang_items::LangItem;
-
-pub mod collector;
-pub mod partitioning;
-pub mod polymorphize;
-pub mod util;
+mod collector;
+mod partitioning;
+mod polymorphize;
+mod util;
 
 fn custom_coerce_unsize_info<'tcx>(
     tcx: TyCtxt<'tcx>,
@@ -31,3 +43,8 @@ fn custom_coerce_unsize_info<'tcx>(
         }
     }
 }
+
+pub fn provide(providers: &mut Providers) {
+    partitioning::provide(providers);
+    polymorphize::provide(providers);
+}
diff --git a/compiler/rustc_mir/src/monomorphize/partitioning/default.rs b/compiler/rustc_monomorphize/src/partitioning/default.rs
similarity index 99%
rename from compiler/rustc_mir/src/monomorphize/partitioning/default.rs
rename to compiler/rustc_monomorphize/src/partitioning/default.rs
index a559a6ce415a3..429ed53d37977 100644
--- a/compiler/rustc_mir/src/monomorphize/partitioning/default.rs
+++ b/compiler/rustc_monomorphize/src/partitioning/default.rs
@@ -13,9 +13,9 @@ use rustc_middle::ty::{self, DefIdTree, InstanceDef, TyCtxt};
 use rustc_span::symbol::Symbol;
 
 use super::PartitioningCx;
-use crate::monomorphize::collector::InliningMap;
-use crate::monomorphize::partitioning::merging;
-use crate::monomorphize::partitioning::{
+use crate::collector::InliningMap;
+use crate::partitioning::merging;
+use crate::partitioning::{
     MonoItemPlacement, Partitioner, PostInliningPartitioning, PreInliningPartitioning,
 };
 
diff --git a/compiler/rustc_mir/src/monomorphize/partitioning/merging.rs b/compiler/rustc_monomorphize/src/partitioning/merging.rs
similarity index 98%
rename from compiler/rustc_mir/src/monomorphize/partitioning/merging.rs
rename to compiler/rustc_monomorphize/src/partitioning/merging.rs
index cbe366657905a..229468b47ff62 100644
--- a/compiler/rustc_mir/src/monomorphize/partitioning/merging.rs
+++ b/compiler/rustc_monomorphize/src/partitioning/merging.rs
@@ -6,7 +6,7 @@ use rustc_middle::mir::mono::{CodegenUnit, CodegenUnitNameBuilder};
 use rustc_span::symbol::{Symbol, SymbolStr};
 
 use super::PartitioningCx;
-use crate::monomorphize::partitioning::PreInliningPartitioning;
+use crate::partitioning::PreInliningPartitioning;
 
 pub fn merge_codegen_units<'tcx>(
     cx: &PartitioningCx<'_, 'tcx>,
diff --git a/compiler/rustc_mir/src/monomorphize/partitioning/mod.rs b/compiler/rustc_monomorphize/src/partitioning/mod.rs
similarity index 99%
rename from compiler/rustc_mir/src/monomorphize/partitioning/mod.rs
rename to compiler/rustc_monomorphize/src/partitioning/mod.rs
index 6ed0ab8be41ee..7a7a56a034ed2 100644
--- a/compiler/rustc_mir/src/monomorphize/partitioning/mod.rs
+++ b/compiler/rustc_monomorphize/src/partitioning/mod.rs
@@ -105,8 +105,8 @@ use rustc_middle::ty::query::Providers;
 use rustc_middle::ty::TyCtxt;
 use rustc_span::symbol::Symbol;
 
-use crate::monomorphize::collector::InliningMap;
-use crate::monomorphize::collector::{self, MonoItemCollectionMode};
+use crate::collector::InliningMap;
+use crate::collector::{self, MonoItemCollectionMode};
 
 pub struct PartitioningCx<'a, 'tcx> {
     tcx: TyCtxt<'tcx>,
diff --git a/compiler/rustc_mir/src/monomorphize/polymorphize.rs b/compiler/rustc_monomorphize/src/polymorphize.rs
similarity index 100%
rename from compiler/rustc_mir/src/monomorphize/polymorphize.rs
rename to compiler/rustc_monomorphize/src/polymorphize.rs
diff --git a/compiler/rustc_mir/src/monomorphize/util.rs b/compiler/rustc_monomorphize/src/util.rs
similarity index 100%
rename from compiler/rustc_mir/src/monomorphize/util.rs
rename to compiler/rustc_monomorphize/src/util.rs
diff --git a/compiler/rustc_typeck/src/check/generator_interior.rs b/compiler/rustc_typeck/src/check/generator_interior.rs
index 5f26e701c0ab7..3da9fd159a728 100644
--- a/compiler/rustc_typeck/src/check/generator_interior.rs
+++ b/compiler/rustc_typeck/src/check/generator_interior.rs
@@ -1,6 +1,6 @@
 //! This calculates the types which has storage which lives across a suspension point in a
 //! generator from the perspective of typeck. The actual types used at runtime
-//! is calculated in `rustc_mir::transform::generator` and may be a subset of the
+//! is calculated in `rustc_const_eval::transform::generator` and may be a subset of the
 //! types computed here.
 
 use super::FnCtxt;
diff --git a/src/librustdoc/clean/mod.rs b/src/librustdoc/clean/mod.rs
index 71348b3eb65ff..f2941e67ac30a 100644
--- a/src/librustdoc/clean/mod.rs
+++ b/src/librustdoc/clean/mod.rs
@@ -11,6 +11,7 @@ crate mod utils;
 
 use rustc_ast as ast;
 use rustc_attr as attr;
+use rustc_const_eval::const_eval::{is_const_fn, is_unstable_const_fn};
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_hir as hir;
 use rustc_hir::def::{CtorKind, DefKind, Res};
@@ -22,7 +23,6 @@ use rustc_middle::ty::fold::TypeFolder;
 use rustc_middle::ty::subst::{InternalSubsts, Subst};
 use rustc_middle::ty::{self, AdtKind, DefIdTree, Lift, Ty, TyCtxt};
 use rustc_middle::{bug, span_bug};
-use rustc_mir::const_eval::{is_const_fn, is_unstable_const_fn};
 use rustc_span::hygiene::{AstPass, MacroKind};
 use rustc_span::symbol::{kw, sym, Ident, Symbol};
 use rustc_span::{self, ExpnKind};
diff --git a/src/librustdoc/lib.rs b/src/librustdoc/lib.rs
index 2dbe4c42b888e..8246834a74688 100644
--- a/src/librustdoc/lib.rs
+++ b/src/librustdoc/lib.rs
@@ -34,6 +34,7 @@ extern crate rustc_ast;
 extern crate rustc_ast_lowering;
 extern crate rustc_ast_pretty;
 extern crate rustc_attr;
+extern crate rustc_const_eval;
 extern crate rustc_data_structures;
 extern crate rustc_driver;
 extern crate rustc_errors;
@@ -49,7 +50,6 @@ extern crate rustc_lint;
 extern crate rustc_lint_defs;
 extern crate rustc_metadata;
 extern crate rustc_middle;
-extern crate rustc_mir;
 extern crate rustc_parse;
 extern crate rustc_passes;
 extern crate rustc_resolve;
diff --git a/src/test/run-make-fulldeps/obtain-borrowck/driver.rs b/src/test/run-make-fulldeps/obtain-borrowck/driver.rs
index 308df0b030c27..961ea518c13ab 100644
--- a/src/test/run-make-fulldeps/obtain-borrowck/driver.rs
+++ b/src/test/run-make-fulldeps/obtain-borrowck/driver.rs
@@ -11,13 +11,14 @@
 //! `optimized_mir` and pulls out the MIR bodies with the borrowck information
 //! from the thread local storage.
 
+extern crate rustc_borrowck;
 extern crate rustc_driver;
 extern crate rustc_hir;
 extern crate rustc_interface;
 extern crate rustc_middle;
-extern crate rustc_mir;
 extern crate rustc_session;
 
+use rustc_borrowck::consumers::BodyWithBorrowckFacts;
 use rustc_driver::Compilation;
 use rustc_hir::def_id::LocalDefId;
 use rustc_hir::itemlikevisit::ItemLikeVisitor;
@@ -26,7 +27,6 @@ use rustc_interface::{Config, Queries};
 use rustc_middle::ty::query::query_values::mir_borrowck;
 use rustc_middle::ty::query::Providers;
 use rustc_middle::ty::{self, TyCtxt};
-use rustc_mir::consumers::BodyWithBorrowckFacts;
 use rustc_session::Session;
 use std::cell::RefCell;
 use std::collections::HashMap;
@@ -108,7 +108,7 @@ thread_local! {
 }
 
 fn mir_borrowck<'tcx>(tcx: TyCtxt<'tcx>, def_id: LocalDefId) -> mir_borrowck<'tcx> {
-    let body_with_facts = rustc_mir::consumers::get_body_with_borrowck_facts(
+    let body_with_facts = rustc_borrowck::consumers::get_body_with_borrowck_facts(
         tcx,
         ty::WithOptConstParam::unknown(def_id),
     );
@@ -120,7 +120,7 @@ fn mir_borrowck<'tcx>(tcx: TyCtxt<'tcx>, def_id: LocalDefId) -> mir_borrowck<'tc
         assert!(map.insert(def_id, body_with_facts).is_none());
     });
     let mut providers = Providers::default();
-    rustc_mir::provide(&mut providers);
+    rustc_borrowck::provide(&mut providers);
     let original_mir_borrowck = providers.mir_borrowck;
     original_mir_borrowck(tcx, def_id)
 }
diff --git a/src/test/run-make-fulldeps/sepcomp-cci-copies/Makefile b/src/test/run-make-fulldeps/sepcomp-cci-copies/Makefile
index 36f913ff3faac..77d1d71e9b269 100644
--- a/src/test/run-make-fulldeps/sepcomp-cci-copies/Makefile
+++ b/src/test/run-make-fulldeps/sepcomp-cci-copies/Makefile
@@ -3,7 +3,7 @@
 # Check that cross-crate inlined items are inlined in all compilation units
 # that refer to them, and not in any other compilation units.
 # Note that we have to pass `-C codegen-units=6` because up to two CGUs may be
-# created for each source module (see `rustc_mir::monomorphize::partitioning`).
+# created for each source module (see `rustc_const_eval::monomorphize::partitioning`).
 
 all:
 	$(RUSTC) cci_lib.rs
diff --git a/src/tools/clippy/clippy_lints/src/lib.rs b/src/tools/clippy/clippy_lints/src/lib.rs
index 19719502870bd..3c6faf117fde5 100644
--- a/src/tools/clippy/clippy_lints/src/lib.rs
+++ b/src/tools/clippy/clippy_lints/src/lib.rs
@@ -31,7 +31,7 @@ extern crate rustc_infer;
 extern crate rustc_lexer;
 extern crate rustc_lint;
 extern crate rustc_middle;
-extern crate rustc_mir;
+extern crate rustc_mir_dataflow;
 extern crate rustc_parse;
 extern crate rustc_parse_format;
 extern crate rustc_session;
diff --git a/src/tools/clippy/clippy_lints/src/redundant_clone.rs b/src/tools/clippy/clippy_lints/src/redundant_clone.rs
index f5e43264a5c69..7041e4f980ef4 100644
--- a/src/tools/clippy/clippy_lints/src/redundant_clone.rs
+++ b/src/tools/clippy/clippy_lints/src/redundant_clone.rs
@@ -15,7 +15,7 @@ use rustc_middle::mir::{
     Mutability,
 };
 use rustc_middle::ty::{self, fold::TypeVisitor, Ty, TyCtxt};
-use rustc_mir::dataflow::{Analysis, AnalysisDomain, GenKill, GenKillAnalysis, ResultsCursor};
+use rustc_mir_dataflow::{Analysis, AnalysisDomain, GenKill, GenKillAnalysis, ResultsCursor};
 use rustc_session::{declare_lint_pass, declare_tool_lint};
 use rustc_span::source_map::{BytePos, Span};
 use rustc_span::sym;
@@ -625,7 +625,10 @@ impl<'a, 'tcx> mir::visit::Visitor<'tcx> for PossibleBorrowerVisitor<'a, 'tcx> {
                 .flat_map(HybridBitSet::iter)
                 .collect();
 
-            if ContainsRegion(self.cx.tcx).visit_ty(self.body.local_decls[*dest].ty).is_break() {
+            if ContainsRegion(self.cx.tcx)
+                .visit_ty(self.body.local_decls[*dest].ty)
+                .is_break()
+            {
                 mutable_variables.push(*dest);
             }
 
diff --git a/src/tools/clippy/clippy_utils/src/lib.rs b/src/tools/clippy/clippy_utils/src/lib.rs
index ddff1686ba2ce..0906f958cfb1f 100644
--- a/src/tools/clippy/clippy_utils/src/lib.rs
+++ b/src/tools/clippy/clippy_utils/src/lib.rs
@@ -17,6 +17,7 @@
 extern crate rustc_ast;
 extern crate rustc_ast_pretty;
 extern crate rustc_attr;
+extern crate rustc_const_eval;
 extern crate rustc_data_structures;
 extern crate rustc_errors;
 extern crate rustc_hir;
@@ -24,7 +25,6 @@ extern crate rustc_infer;
 extern crate rustc_lexer;
 extern crate rustc_lint;
 extern crate rustc_middle;
-extern crate rustc_mir;
 extern crate rustc_session;
 extern crate rustc_span;
 extern crate rustc_target;
diff --git a/src/tools/clippy/clippy_utils/src/qualify_min_const_fn.rs b/src/tools/clippy/clippy_utils/src/qualify_min_const_fn.rs
index e5bbf75c3b0a1..4fb9e6b07e71a 100644
--- a/src/tools/clippy/clippy_utils/src/qualify_min_const_fn.rs
+++ b/src/tools/clippy/clippy_utils/src/qualify_min_const_fn.rs
@@ -366,7 +366,7 @@ fn check_terminator(
 }
 
 fn is_const_fn(tcx: TyCtxt<'_>, def_id: DefId, msrv: Option<&RustcVersion>) -> bool {
-    rustc_mir::const_eval::is_const_fn(tcx, def_id)
+    rustc_const_eval::const_eval::is_const_fn(tcx, def_id)
         && tcx.lookup_const_stability(def_id).map_or(true, |const_stab| {
             if let rustc_attr::StabilityLevel::Stable { since } = const_stab.level {
                 // Checking MSRV is manually necessary because `rustc` has no such concept. This entire