diff --git a/src/test/mir-opt/array_index_is_temporary.main.SimplifyCfg-elaborate-drops.after.64bit.mir b/src/test/mir-opt/array_index_is_temporary.main.SimplifyCfg-elaborate-drops.after.64bit.mir
index 2216c2bc92a55..deb5dbad7de67 100644
--- a/src/test/mir-opt/array_index_is_temporary.main.SimplifyCfg-elaborate-drops.after.64bit.mir
+++ b/src/test/mir-opt/array_index_is_temporary.main.SimplifyCfg-elaborate-drops.after.64bit.mir
@@ -48,7 +48,7 @@ fn main() -> () {
         _7 = _2;                         // scope 3 at $DIR/array-index-is-temporary.rs:16:7: 16:8
         _8 = Len(_1);                    // scope 3 at $DIR/array-index-is-temporary.rs:16:5: 16:9
         _9 = Lt(_7, _8);                 // scope 3 at $DIR/array-index-is-temporary.rs:16:5: 16:9
-        assert(move _9, "index out of bounds: the len is {} but the index is {}", move _8, _7) -> bb2; // scope 3 at $DIR/array-index-is-temporary.rs:16:5: 16:9
+        assert(move _9, "index out of bounds: the length is {} but the index is {}", move _8, _7) -> bb2; // scope 3 at $DIR/array-index-is-temporary.rs:16:5: 16:9
     }
 
     bb2: {
diff --git a/src/test/mir-opt/combine_array_len.norm2.InstCombine.64bit.diff b/src/test/mir-opt/combine_array_len.norm2.InstCombine.64bit.diff
index 61e987cc68516..979e5bc4d2118 100644
--- a/src/test/mir-opt/combine_array_len.norm2.InstCombine.64bit.diff
+++ b/src/test/mir-opt/combine_array_len.norm2.InstCombine.64bit.diff
@@ -32,7 +32,7 @@
 -         _4 = Len(_1);                    // scope 0 at $DIR/combine_array_len.rs:5:13: 5:17
 +         _4 = const 2_usize;              // scope 0 at $DIR/combine_array_len.rs:5:13: 5:17
           _5 = Lt(_3, _4);                 // scope 0 at $DIR/combine_array_len.rs:5:13: 5:17
-          assert(move _5, "index out of bounds: the len is {} but the index is {}", move _4, _3) -> bb1; // scope 0 at $DIR/combine_array_len.rs:5:13: 5:17
+          assert(move _5, "index out of bounds: the length is {} but the index is {}", move _4, _3) -> bb1; // scope 0 at $DIR/combine_array_len.rs:5:13: 5:17
       }
   
       bb1: {
@@ -44,7 +44,7 @@
 -         _8 = Len(_1);                    // scope 1 at $DIR/combine_array_len.rs:6:13: 6:17
 +         _8 = const 2_usize;              // scope 1 at $DIR/combine_array_len.rs:6:13: 6:17
           _9 = Lt(_7, _8);                 // scope 1 at $DIR/combine_array_len.rs:6:13: 6:17
-          assert(move _9, "index out of bounds: the len is {} but the index is {}", move _8, _7) -> bb2; // scope 1 at $DIR/combine_array_len.rs:6:13: 6:17
+          assert(move _9, "index out of bounds: the length is {} but the index is {}", move _8, _7) -> bb2; // scope 1 at $DIR/combine_array_len.rs:6:13: 6:17
       }
   
       bb2: {
diff --git a/src/test/mir-opt/const_prop/array_index.main.ConstProp.64bit.diff b/src/test/mir-opt/const_prop/array_index.main.ConstProp.64bit.diff
index 1ccda1c5003dc..4664934690845 100644
--- a/src/test/mir-opt/const_prop/array_index.main.ConstProp.64bit.diff
+++ b/src/test/mir-opt/const_prop/array_index.main.ConstProp.64bit.diff
@@ -20,9 +20,9 @@
           _3 = const 2_usize;              // scope 0 at $DIR/array_index.rs:5:31: 5:32
           _4 = const 4_usize;              // scope 0 at $DIR/array_index.rs:5:18: 5:33
 -         _5 = Lt(_3, _4);                 // scope 0 at $DIR/array_index.rs:5:18: 5:33
--         assert(move _5, "index out of bounds: the len is {} but the index is {}", move _4, _3) -> bb1; // scope 0 at $DIR/array_index.rs:5:18: 5:33
+-         assert(move _5, "index out of bounds: the length is {} but the index is {}", move _4, _3) -> bb1; // scope 0 at $DIR/array_index.rs:5:18: 5:33
 +         _5 = const true;                 // scope 0 at $DIR/array_index.rs:5:18: 5:33
-+         assert(const true, "index out of bounds: the len is {} but the index is {}", const 4_usize, const 2_usize) -> bb1; // scope 0 at $DIR/array_index.rs:5:18: 5:33
++         assert(const true, "index out of bounds: the length is {} but the index is {}", const 4_usize, const 2_usize) -> bb1; // scope 0 at $DIR/array_index.rs:5:18: 5:33
       }
   
       bb1: {
diff --git a/src/test/mir-opt/const_prop/bad_op_unsafe_oob_for_slices.main.ConstProp.64bit.diff b/src/test/mir-opt/const_prop/bad_op_unsafe_oob_for_slices.main.ConstProp.64bit.diff
index 245a7de5e9925..ec00fcf20c4d6 100644
--- a/src/test/mir-opt/const_prop/bad_op_unsafe_oob_for_slices.main.ConstProp.64bit.diff
+++ b/src/test/mir-opt/const_prop/bad_op_unsafe_oob_for_slices.main.ConstProp.64bit.diff
@@ -42,9 +42,9 @@
           _6 = const 3_usize;              // scope 2 at $DIR/bad_op_unsafe_oob_for_slices.rs:7:23: 7:24
           _7 = Len((*_1));                 // scope 2 at $DIR/bad_op_unsafe_oob_for_slices.rs:7:18: 7:25
 -         _8 = Lt(_6, _7);                 // scope 2 at $DIR/bad_op_unsafe_oob_for_slices.rs:7:18: 7:25
--         assert(move _8, "index out of bounds: the len is {} but the index is {}", move _7, _6) -> bb1; // scope 2 at $DIR/bad_op_unsafe_oob_for_slices.rs:7:18: 7:25
+-         assert(move _8, "index out of bounds: the length is {} but the index is {}", move _7, _6) -> bb1; // scope 2 at $DIR/bad_op_unsafe_oob_for_slices.rs:7:18: 7:25
 +         _8 = Lt(const 3_usize, _7);      // scope 2 at $DIR/bad_op_unsafe_oob_for_slices.rs:7:18: 7:25
-+         assert(move _8, "index out of bounds: the len is {} but the index is {}", move _7, const 3_usize) -> bb1; // scope 2 at $DIR/bad_op_unsafe_oob_for_slices.rs:7:18: 7:25
++         assert(move _8, "index out of bounds: the length is {} but the index is {}", move _7, const 3_usize) -> bb1; // scope 2 at $DIR/bad_op_unsafe_oob_for_slices.rs:7:18: 7:25
       }
   
       bb1: {
diff --git a/src/test/mir-opt/const_prop/large_array_index.main.ConstProp.64bit.diff b/src/test/mir-opt/const_prop/large_array_index.main.ConstProp.64bit.diff
index b1a9e1cb5d7de..fa790822b6bff 100644
--- a/src/test/mir-opt/const_prop/large_array_index.main.ConstProp.64bit.diff
+++ b/src/test/mir-opt/const_prop/large_array_index.main.ConstProp.64bit.diff
@@ -20,9 +20,9 @@
           _3 = const 2_usize;              // scope 0 at $DIR/large_array_index.rs:6:30: 6:31
           _4 = const 5000_usize;           // scope 0 at $DIR/large_array_index.rs:6:17: 6:32
 -         _5 = Lt(_3, _4);                 // scope 0 at $DIR/large_array_index.rs:6:17: 6:32
--         assert(move _5, "index out of bounds: the len is {} but the index is {}", move _4, _3) -> bb1; // scope 0 at $DIR/large_array_index.rs:6:17: 6:32
+-         assert(move _5, "index out of bounds: the length is {} but the index is {}", move _4, _3) -> bb1; // scope 0 at $DIR/large_array_index.rs:6:17: 6:32
 +         _5 = const true;                 // scope 0 at $DIR/large_array_index.rs:6:17: 6:32
-+         assert(const true, "index out of bounds: the len is {} but the index is {}", const 5000_usize, const 2_usize) -> bb1; // scope 0 at $DIR/large_array_index.rs:6:17: 6:32
++         assert(const true, "index out of bounds: the length is {} but the index is {}", const 5000_usize, const 2_usize) -> bb1; // scope 0 at $DIR/large_array_index.rs:6:17: 6:32
       }
   
       bb1: {
diff --git a/src/test/mir-opt/const_prop/optimizes_into_variable.main.ConstProp.64bit.diff b/src/test/mir-opt/const_prop/optimizes_into_variable.main.ConstProp.64bit.diff
index 2c8e7ada39b0a..53ffc01ccaf25 100644
--- a/src/test/mir-opt/const_prop/optimizes_into_variable.main.ConstProp.64bit.diff
+++ b/src/test/mir-opt/const_prop/optimizes_into_variable.main.ConstProp.64bit.diff
@@ -25,7 +25,7 @@
       bb0: {
           StorageLive(_1);                 // scope 0 at $DIR/optimizes_into_variable.rs:12:9: 12:10
 -         _2 = CheckedAdd(const 2_i32, const 2_i32); // scope 0 at $DIR/optimizes_into_variable.rs:12:13: 12:18
--         assert(!move (_2.1: bool), "attempt to compute `{} + {}` which would overflow", const 2_i32, const 2_i32) -> bb1; // scope 0 at $DIR/optimizes_into_variable.rs:12:13: 12:18
+-         assert(!move (_2.1: bool), "attempt to compute `{} + {}`, which would overflow", const 2_i32, const 2_i32) -> bb1; // scope 0 at $DIR/optimizes_into_variable.rs:12:13: 12:18
 +         _2 = const (4_i32, false);       // scope 0 at $DIR/optimizes_into_variable.rs:12:13: 12:18
 +                                          // ty::Const
 +                                          // + ty: (i32, bool)
@@ -33,7 +33,7 @@
 +                                          // mir::Constant
 +                                          // + span: $DIR/optimizes_into_variable.rs:12:13: 12:18
 +                                          // + literal: Const { ty: (i32, bool), val: Value(ByRef { alloc: Allocation { bytes: [4, 0, 0, 0, 0, 0, 0, 0], relocations: Relocations(SortedMap { data: [] }), init_mask: InitMask { blocks: [31], len: Size { raw: 8 } }, size: Size { raw: 8 }, align: Align { pow2: 2 }, mutability: Not, extra: () }, offset: Size { raw: 0 } }) }
-+         assert(!const false, "attempt to compute `{} + {}` which would overflow", const 2_i32, const 2_i32) -> bb1; // scope 0 at $DIR/optimizes_into_variable.rs:12:13: 12:18
++         assert(!const false, "attempt to compute `{} + {}`, which would overflow", const 2_i32, const 2_i32) -> bb1; // scope 0 at $DIR/optimizes_into_variable.rs:12:13: 12:18
       }
   
       bb1: {
@@ -46,9 +46,9 @@
           _5 = const 3_usize;              // scope 1 at $DIR/optimizes_into_variable.rs:13:32: 13:33
           _6 = const 6_usize;              // scope 1 at $DIR/optimizes_into_variable.rs:13:13: 13:34
 -         _7 = Lt(_5, _6);                 // scope 1 at $DIR/optimizes_into_variable.rs:13:13: 13:34
--         assert(move _7, "index out of bounds: the len is {} but the index is {}", move _6, _5) -> bb2; // scope 1 at $DIR/optimizes_into_variable.rs:13:13: 13:34
+-         assert(move _7, "index out of bounds: the length is {} but the index is {}", move _6, _5) -> bb2; // scope 1 at $DIR/optimizes_into_variable.rs:13:13: 13:34
 +         _7 = const true;                 // scope 1 at $DIR/optimizes_into_variable.rs:13:13: 13:34
-+         assert(const true, "index out of bounds: the len is {} but the index is {}", const 6_usize, const 3_usize) -> bb2; // scope 1 at $DIR/optimizes_into_variable.rs:13:13: 13:34
++         assert(const true, "index out of bounds: the length is {} but the index is {}", const 6_usize, const 3_usize) -> bb2; // scope 1 at $DIR/optimizes_into_variable.rs:13:13: 13:34
       }
   
       bb2: {
diff --git a/src/test/mir-opt/const_prop/repeat.main.ConstProp.64bit.diff b/src/test/mir-opt/const_prop/repeat.main.ConstProp.64bit.diff
index f14004fc25e00..98f409f326a58 100644
--- a/src/test/mir-opt/const_prop/repeat.main.ConstProp.64bit.diff
+++ b/src/test/mir-opt/const_prop/repeat.main.ConstProp.64bit.diff
@@ -22,9 +22,9 @@
           _4 = const 2_usize;              // scope 0 at $DIR/repeat.rs:6:26: 6:27
           _5 = const 8_usize;              // scope 0 at $DIR/repeat.rs:6:18: 6:28
 -         _6 = Lt(_4, _5);                 // scope 0 at $DIR/repeat.rs:6:18: 6:28
--         assert(move _6, "index out of bounds: the len is {} but the index is {}", move _5, _4) -> bb1; // scope 0 at $DIR/repeat.rs:6:18: 6:28
+-         assert(move _6, "index out of bounds: the length is {} but the index is {}", move _5, _4) -> bb1; // scope 0 at $DIR/repeat.rs:6:18: 6:28
 +         _6 = const true;                 // scope 0 at $DIR/repeat.rs:6:18: 6:28
-+         assert(const true, "index out of bounds: the len is {} but the index is {}", const 8_usize, const 2_usize) -> bb1; // scope 0 at $DIR/repeat.rs:6:18: 6:28
++         assert(const true, "index out of bounds: the length is {} but the index is {}", const 8_usize, const 2_usize) -> bb1; // scope 0 at $DIR/repeat.rs:6:18: 6:28
       }
   
       bb1: {
diff --git a/src/test/mir-opt/const_prop/slice_len.main.ConstProp.64bit.diff b/src/test/mir-opt/const_prop/slice_len.main.ConstProp.64bit.diff
index 02c4391baf560..98e5b5cedc2bb 100644
--- a/src/test/mir-opt/const_prop/slice_len.main.ConstProp.64bit.diff
+++ b/src/test/mir-opt/const_prop/slice_len.main.ConstProp.64bit.diff
@@ -33,10 +33,10 @@
           _6 = const 1_usize;              // scope 0 at $DIR/slice_len.rs:5:31: 5:32
 -         _7 = Len((*_2));                 // scope 0 at $DIR/slice_len.rs:5:5: 5:33
 -         _8 = Lt(_6, _7);                 // scope 0 at $DIR/slice_len.rs:5:5: 5:33
--         assert(move _8, "index out of bounds: the len is {} but the index is {}", move _7, _6) -> bb1; // scope 0 at $DIR/slice_len.rs:5:5: 5:33
+-         assert(move _8, "index out of bounds: the length is {} but the index is {}", move _7, _6) -> bb1; // scope 0 at $DIR/slice_len.rs:5:5: 5:33
 +         _7 = const 3_usize;              // scope 0 at $DIR/slice_len.rs:5:5: 5:33
 +         _8 = const true;                 // scope 0 at $DIR/slice_len.rs:5:5: 5:33
-+         assert(const true, "index out of bounds: the len is {} but the index is {}", const 3_usize, const 1_usize) -> bb1; // scope 0 at $DIR/slice_len.rs:5:5: 5:33
++         assert(const true, "index out of bounds: the length is {} but the index is {}", const 3_usize, const 1_usize) -> bb1; // scope 0 at $DIR/slice_len.rs:5:5: 5:33
       }
   
       bb1: {
diff --git a/src/test/mir-opt/issue_41697.{{impl}}-{{constant}}.SimplifyCfg-promote-consts.after.64bit.mir b/src/test/mir-opt/issue_41697.{{impl}}-{{constant}}.SimplifyCfg-promote-consts.after.64bit.mir
index 1cef88fd1096b..84a1149ba1879 100644
--- a/src/test/mir-opt/issue_41697.{{impl}}-{{constant}}.SimplifyCfg-promote-consts.after.64bit.mir
+++ b/src/test/mir-opt/issue_41697.{{impl}}-{{constant}}.SimplifyCfg-promote-consts.after.64bit.mir
@@ -6,7 +6,7 @@
 
     bb0: {
         _1 = CheckedAdd(const 1_usize, const 1_usize); // scope 0 at $DIR/issue-41697.rs:18:19: 18:22
-        assert(!move (_1.1: bool), "attempt to compute `{} + {}` which would overflow", const 1_usize, const 1_usize) -> [success: bb2, unwind: bb1]; // scope 0 at $DIR/issue-41697.rs:18:19: 18:22
+        assert(!move (_1.1: bool), "attempt to compute `{} + {}`, which would overflow", const 1_usize, const 1_usize) -> [success: bb2, unwind: bb1]; // scope 0 at $DIR/issue-41697.rs:18:19: 18:22
     }
 
     bb1 (cleanup): {
diff --git a/src/test/mir-opt/issue_72181.foo.mir_map.0.64bit.mir b/src/test/mir-opt/issue_72181.foo.mir_map.0.64bit.mir
index 972a36a30a127..c94f6c28cd907 100644
--- a/src/test/mir-opt/issue_72181.foo.mir_map.0.64bit.mir
+++ b/src/test/mir-opt/issue_72181.foo.mir_map.0.64bit.mir
@@ -12,7 +12,7 @@ fn foo(_1: [(Never, u32); 1]) -> u32 {
         _2 = const 0_usize;              // scope 0 at $DIR/issue-72181.rs:16:43: 16:44
         _3 = Len(_1);                    // scope 0 at $DIR/issue-72181.rs:16:40: 16:45
         _4 = Lt(_2, _3);                 // scope 0 at $DIR/issue-72181.rs:16:40: 16:45
-        assert(move _4, "index out of bounds: the len is {} but the index is {}", move _3, _2) -> [success: bb2, unwind: bb1]; // scope 0 at $DIR/issue-72181.rs:16:40: 16:45
+        assert(move _4, "index out of bounds: the length is {} but the index is {}", move _3, _2) -> [success: bb2, unwind: bb1]; // scope 0 at $DIR/issue-72181.rs:16:40: 16:45
     }
 
     bb1 (cleanup): {
diff --git a/src/test/mir-opt/issue_72181.main.mir_map.0.64bit.mir b/src/test/mir-opt/issue_72181.main.mir_map.0.64bit.mir
index 89b60121496f4..e003dc2aadb9f 100644
--- a/src/test/mir-opt/issue_72181.main.mir_map.0.64bit.mir
+++ b/src/test/mir-opt/issue_72181.main.mir_map.0.64bit.mir
@@ -48,7 +48,7 @@ fn main() -> () {
         _6 = const 0_usize;              // scope 4 at $DIR/issue-72181.rs:27:24: 27:25
         _7 = Len(_2);                    // scope 4 at $DIR/issue-72181.rs:27:22: 27:26
         _8 = Lt(_6, _7);                 // scope 4 at $DIR/issue-72181.rs:27:22: 27:26
-        assert(move _8, "index out of bounds: the len is {} but the index is {}", move _7, _6) -> [success: bb3, unwind: bb1]; // scope 4 at $DIR/issue-72181.rs:27:22: 27:26
+        assert(move _8, "index out of bounds: the length is {} but the index is {}", move _7, _6) -> [success: bb3, unwind: bb1]; // scope 4 at $DIR/issue-72181.rs:27:22: 27:26
     }
 
     bb3: {
diff --git a/src/test/mir-opt/nll/region_subtyping_basic.main.nll.0.32bit.mir b/src/test/mir-opt/nll/region_subtyping_basic.main.nll.0.32bit.mir
index 2885dd8eb7845..91135fbf41a71 100644
--- a/src/test/mir-opt/nll/region_subtyping_basic.main.nll.0.32bit.mir
+++ b/src/test/mir-opt/nll/region_subtyping_basic.main.nll.0.32bit.mir
@@ -52,7 +52,7 @@ fn main() -> () {
         _3 = const Const(Value(Scalar(0x00000000)): usize); // bb0[5]: scope 1 at $DIR/region-subtyping-basic.rs:18:16: 18:17
         _4 = Len(_1);                    // bb0[6]: scope 1 at $DIR/region-subtyping-basic.rs:18:14: 18:18
         _5 = Lt(_3, _4);                 // bb0[7]: scope 1 at $DIR/region-subtyping-basic.rs:18:14: 18:18
-        assert(move _5, "index out of bounds: the len is {} but the index is {}", move _4, _3) -> [success: bb2, unwind: bb1]; // bb0[8]: scope 1 at $DIR/region-subtyping-basic.rs:18:14: 18:18
+        assert(move _5, "index out of bounds: the length is {} but the index is {}", move _4, _3) -> [success: bb2, unwind: bb1]; // bb0[8]: scope 1 at $DIR/region-subtyping-basic.rs:18:14: 18:18
     }
 
     bb1 (cleanup): {