diff --git a/src/librustc_borrowck/borrowck/gather_loans/lifetime.rs b/src/librustc_borrowck/borrowck/gather_loans/lifetime.rs
index 0e08b62668ac8..9680dd4ce2faf 100644
--- a/src/librustc_borrowck/borrowck/gather_loans/lifetime.rs
+++ b/src/librustc_borrowck/borrowck/gather_loans/lifetime.rs
@@ -2,13 +2,13 @@
 //! does not exceed the lifetime of the value being borrowed.
 
 use crate::borrowck::*;
+use rustc::hir::HirId;
 use rustc::middle::expr_use_visitor as euv;
 use rustc::middle::mem_categorization as mc;
 use rustc::middle::mem_categorization::Categorization;
 use rustc::middle::region;
 use rustc::ty;
 
-use syntax::ast;
 use syntax_pos::Span;
 use log::debug;
 
@@ -51,7 +51,7 @@ struct GuaranteeLifetimeContext<'a, 'tcx: 'a> {
 }
 
 impl<'a, 'tcx> GuaranteeLifetimeContext<'a, 'tcx> {
-    fn check(&self, cmt: &mc::cmt_<'tcx>, discr_scope: Option<ast::NodeId>) -> R {
+    fn check(&self, cmt: &mc::cmt_<'tcx>, discr_scope: Option<HirId>) -> R {
         //! Main routine. Walks down `cmt` until we find the
         //! "guarantor". Reports an error if `self.loan_region` is
         //! larger than scope of `cmt`.
diff --git a/src/librustc_borrowck/borrowck/gather_loans/mod.rs b/src/librustc_borrowck/borrowck/gather_loans/mod.rs
index bf730ba41f428..ed631f2cdaa0d 100644
--- a/src/librustc_borrowck/borrowck/gather_loans/mod.rs
+++ b/src/librustc_borrowck/borrowck/gather_loans/mod.rs
@@ -14,7 +14,6 @@ use rustc::middle::mem_categorization::Categorization;
 use rustc::middle::region;
 use rustc::ty::{self, TyCtxt};
 
-use syntax::ast;
 use syntax_pos::Span;
 use rustc::hir;
 use log::debug;
@@ -141,8 +140,7 @@ impl<'a, 'tcx> euv::Delegate<'tcx> for GatherLoanCtxt<'a, 'tcx> {
               assignee_cmt: &mc::cmt_<'tcx>,
               _: euv::MutateMode)
     {
-        let node_id = self.bccx.tcx.hir().hir_to_node_id(assignment_id);
-        self.guarantee_assignment_valid(node_id,
+        self.guarantee_assignment_valid(assignment_id,
                                         assignment_span,
                                         assignee_cmt);
     }
@@ -238,7 +236,7 @@ impl<'a, 'tcx> GatherLoanCtxt<'a, 'tcx> {
 
     /// Guarantees that `cmt` is assignable, or reports an error.
     fn guarantee_assignment_valid(&mut self,
-                                  assignment_id: ast::NodeId,
+                                  assignment_id: hir::HirId,
                                   assignment_span: Span,
                                   cmt: &mc::cmt_<'tcx>) {
 
@@ -272,8 +270,7 @@ impl<'a, 'tcx> GatherLoanCtxt<'a, 'tcx> {
                     self.mark_loan_path_as_mutated(&lp);
                 }
                 gather_moves::gather_assignment(self.bccx, &self.move_data,
-                                                self.bccx.tcx.hir().node_to_hir_id(assignment_id)
-                                                    .local_id,
+                                                assignment_id.local_id,
                                                 assignment_span,
                                                 lp);
             }
diff --git a/src/librustc_borrowck/borrowck/mod.rs b/src/librustc_borrowck/borrowck/mod.rs
index da065f9e05d9e..3a6e53a92482c 100644
--- a/src/librustc_borrowck/borrowck/mod.rs
+++ b/src/librustc_borrowck/borrowck/mod.rs
@@ -34,7 +34,6 @@ use std::fmt;
 use std::rc::Rc;
 use rustc_data_structures::sync::Lrc;
 use std::hash::{Hash, Hasher};
-use syntax::ast;
 use syntax_pos::{MultiSpan, Span};
 use errors::{Applicability, DiagnosticBuilder, DiagnosticId};
 use log::debug;
@@ -399,12 +398,12 @@ pub enum LoanPathElem<'tcx> {
 }
 
 fn closure_to_block(closure_id: LocalDefId,
-                    tcx: TyCtxt<'_, '_, '_>) -> ast::NodeId {
+                    tcx: TyCtxt<'_, '_, '_>) -> HirId {
     let closure_id = tcx.hir().local_def_id_to_node_id(closure_id);
     match tcx.hir().get(closure_id) {
         Node::Expr(expr) => match expr.node {
             hir::ExprKind::Closure(.., body_id, _, _) => {
-                tcx.hir().hir_to_node_id(body_id.hir_id)
+                body_id.hir_id
             }
             _ => {
                 bug!("encountered non-closure id: {}", closure_id)
@@ -422,8 +421,7 @@ impl<'a, 'tcx> LoanPath<'tcx> {
             }
             LpUpvar(upvar_id) => {
                 let block_id = closure_to_block(upvar_id.closure_expr_id, bccx.tcx);
-                let hir_id = bccx.tcx.hir().node_to_hir_id(block_id);
-                region::Scope { id: hir_id.local_id, data: region::ScopeData::Node }
+                region::Scope { id: block_id.local_id, data: region::ScopeData::Node }
             }
             LpDowncast(ref base, _) |
             LpExtend(ref base, ..) => base.kill_scope(bccx),