diff --git a/compiler/rustc_const_eval/src/interpret/cast.rs b/compiler/rustc_const_eval/src/interpret/cast.rs
index 6d470ff162e..a88e130cd4b 100644
--- a/compiler/rustc_const_eval/src/interpret/cast.rs
+++ b/compiler/rustc_const_eval/src/interpret/cast.rs
@@ -153,7 +153,7 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
                     );
                 }
 
-                self.copy_op(src, dest, /*allow_transmute*/ true)?;
+                self.copy_op_allow_transmute(src, dest)?;
             }
         }
         Ok(())
@@ -441,7 +441,7 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
                     if src_field.layout.is_1zst() && cast_ty_field.is_1zst() {
                         // Skip 1-ZST fields.
                     } else if src_field.layout.ty == cast_ty_field.ty {
-                        self.copy_op(&src_field, &dst_field, /*allow_transmute*/ false)?;
+                        self.copy_op(&src_field, &dst_field)?;
                     } else {
                         if found_cast_field {
                             span_bug!(self.cur_span(), "unsize_into: more than one field to cast");
diff --git a/compiler/rustc_const_eval/src/interpret/eval_context.rs b/compiler/rustc_const_eval/src/interpret/eval_context.rs
index 8af69220e03..d45e8a19717 100644
--- a/compiler/rustc_const_eval/src/interpret/eval_context.rs
+++ b/compiler/rustc_const_eval/src/interpret/eval_context.rs
@@ -899,7 +899,7 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
                 .local_to_op(self.frame(), mir::RETURN_PLACE, None)
                 .expect("return place should always be live");
             let dest = self.frame().return_place.clone();
-            let err = self.copy_op(&op, &dest, /*allow_transmute*/ true);
+            let err = self.copy_op_allow_transmute(&op, &dest);
             trace!("return value: {:?}", self.dump_place(&dest));
             // We delay actually short-circuiting on this error until *after* the stack frame is
             // popped, since we want this error to be attributed to the caller, whose type defines
diff --git a/compiler/rustc_const_eval/src/interpret/intrinsics.rs b/compiler/rustc_const_eval/src/interpret/intrinsics.rs
index 7991f90b815..f020616f6d8 100644
--- a/compiler/rustc_const_eval/src/interpret/intrinsics.rs
+++ b/compiler/rustc_const_eval/src/interpret/intrinsics.rs
@@ -120,7 +120,7 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
                 let val = self.tcx.span_as_caller_location(span);
                 let val =
                     self.const_val_to_op(val, self.tcx.caller_location_ty(), Some(dest.layout))?;
-                self.copy_op(&val, dest, /* allow_transmute */ false)?;
+                self.copy_op(&val, dest)?;
             }
 
             sym::min_align_of_val | sym::size_of_val => {
@@ -157,7 +157,7 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
                     tcx.const_eval_global_id(self.param_env, gid, Some(tcx.span))
                 })?;
                 let val = self.const_val_to_op(val, ty, Some(dest.layout))?;
-                self.copy_op(&val, dest, /*allow_transmute*/ false)?;
+                self.copy_op(&val, dest)?;
             }
 
             sym::ctpop
@@ -391,7 +391,7 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
                     } else {
                         self.project_index(&input, i)?.into()
                     };
-                    self.copy_op(&value, &place, /*allow_transmute*/ false)?;
+                    self.copy_op(&value, &place)?;
                 }
             }
             sym::simd_extract => {
@@ -401,15 +401,11 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
                     index < input_len,
                     "index `{index}` must be in bounds of vector with length {input_len}"
                 );
-                self.copy_op(
-                    &self.project_index(&input, index)?,
-                    dest,
-                    /*allow_transmute*/ false,
-                )?;
+                self.copy_op(&self.project_index(&input, index)?, dest)?;
             }
             sym::likely | sym::unlikely | sym::black_box => {
                 // These just return their argument
-                self.copy_op(&args[0], dest, /*allow_transmute*/ false)?;
+                self.copy_op(&args[0], dest)?;
             }
             sym::raw_eq => {
                 let result = self.raw_eq_intrinsic(&args[0], &args[1])?;
diff --git a/compiler/rustc_const_eval/src/interpret/place.rs b/compiler/rustc_const_eval/src/interpret/place.rs
index 03d1dc9fd3d..807d3804d1c 100644
--- a/compiler/rustc_const_eval/src/interpret/place.rs
+++ b/compiler/rustc_const_eval/src/interpret/place.rs
@@ -758,11 +758,32 @@ where
         Ok(())
     }
 
+    /// Copies the data from an operand to a place.
+    /// The layouts of the `src` and `dest` may disagree.
+    #[inline(always)]
+    pub fn copy_op_allow_transmute(
+        &mut self,
+        src: &impl Readable<'tcx, M::Provenance>,
+        dest: &impl Writeable<'tcx, M::Provenance>,
+    ) -> InterpResult<'tcx> {
+        self.copy_op_inner(src, dest, /* allow_transmute */ true)
+    }
+
+    /// Copies the data from an operand to a place.
+    #[inline(always)]
+    pub fn copy_op(
+        &mut self,
+        src: &impl Readable<'tcx, M::Provenance>,
+        dest: &impl Writeable<'tcx, M::Provenance>,
+    ) -> InterpResult<'tcx> {
+        self.copy_op_inner(src, dest, /* allow_transmute */ false)
+    }
+
     /// Copies the data from an operand to a place.
     /// `allow_transmute` indicates whether the layouts may disagree.
     #[inline(always)]
     #[instrument(skip(self), level = "debug")]
-    pub fn copy_op(
+    fn copy_op_inner(
         &mut self,
         src: &impl Readable<'tcx, M::Provenance>,
         dest: &impl Writeable<'tcx, M::Provenance>,
diff --git a/compiler/rustc_const_eval/src/interpret/step.rs b/compiler/rustc_const_eval/src/interpret/step.rs
index 23f3d7eb67d..d4c96f4573d 100644
--- a/compiler/rustc_const_eval/src/interpret/step.rs
+++ b/compiler/rustc_const_eval/src/interpret/step.rs
@@ -151,12 +151,12 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
             Use(ref operand) => {
                 // Avoid recomputing the layout
                 let op = self.eval_operand(operand, Some(dest.layout))?;
-                self.copy_op(&op, &dest, /*allow_transmute*/ false)?;
+                self.copy_op(&op, &dest)?;
             }
 
             CopyForDeref(place) => {
                 let op = self.eval_place_to_op(place, Some(dest.layout))?;
-                self.copy_op(&op, &dest, /* allow_transmute*/ false)?;
+                self.copy_op(&op, &dest)?;
             }
 
             BinaryOp(bin_op, box (ref left, ref right)) => {
@@ -316,7 +316,7 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
             let field_index = active_field_index.unwrap_or(field_index);
             let field_dest = self.project_field(&variant_dest, field_index.as_usize())?;
             let op = self.eval_operand(operand, Some(field_dest.layout))?;
-            self.copy_op(&op, &field_dest, /*allow_transmute*/ false)?;
+            self.copy_op(&op, &field_dest)?;
         }
         self.write_discriminant(variant_index, dest)
     }
@@ -339,7 +339,7 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
         } else {
             // Write the src to the first element.
             let first = self.project_index(&dest, 0)?;
-            self.copy_op(&src, &first, /*allow_transmute*/ false)?;
+            self.copy_op(&src, &first)?;
 
             // This is performance-sensitive code for big static/const arrays! So we
             // avoid writing each operand individually and instead just make many copies
diff --git a/compiler/rustc_const_eval/src/interpret/terminator.rs b/compiler/rustc_const_eval/src/interpret/terminator.rs
index 4037220e5ed..b2207c3d310 100644
--- a/compiler/rustc_const_eval/src/interpret/terminator.rs
+++ b/compiler/rustc_const_eval/src/interpret/terminator.rs
@@ -481,7 +481,7 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
         // FIXME: Depending on the PassMode, this should reset some padding to uninitialized. (This
         // is true for all `copy_op`, but there are a lot of special cases for argument passing
         // specifically.)
-        self.copy_op(&caller_arg_copy, &callee_arg, /*allow_transmute*/ true)?;
+        self.copy_op_allow_transmute(&caller_arg_copy, &callee_arg)?;
         // If this was an in-place pass, protect the place it comes from for the duration of the call.
         if let FnArg::InPlace(place) = caller_arg {
             M::protect_in_place_function_argument(self, place)?;
diff --git a/compiler/rustc_mir_transform/src/gvn.rs b/compiler/rustc_mir_transform/src/gvn.rs
index 370f0db72cb..a080e2423d4 100644
--- a/compiler/rustc_mir_transform/src/gvn.rs
+++ b/compiler/rustc_mir_transform/src/gvn.rs
@@ -399,7 +399,7 @@ impl<'body, 'tcx> VnState<'body, 'tcx> {
                     };
                     for (field_index, op) in fields.into_iter().enumerate() {
                         let field_dest = self.ecx.project_field(&variant_dest, field_index).ok()?;
-                        self.ecx.copy_op(op, &field_dest, /*allow_transmute*/ false).ok()?;
+                        self.ecx.copy_op(op, &field_dest).ok()?;
                     }
                     self.ecx.write_discriminant(variant.unwrap_or(FIRST_VARIANT), &dest).ok()?;
                     self.ecx
@@ -1181,8 +1181,7 @@ fn op_to_prop_const<'tcx>(
     }
 
     // Everything failed: create a new allocation to hold the data.
-    let alloc_id =
-        ecx.intern_with_temp_alloc(op.layout, |ecx, dest| ecx.copy_op(op, dest, false)).ok()?;
+    let alloc_id = ecx.intern_with_temp_alloc(op.layout, |ecx, dest| ecx.copy_op(op, dest)).ok()?;
     let value = ConstValue::Indirect { alloc_id, offset: Size::ZERO };
 
     // Check that we do not leak a pointer.
diff --git a/src/tools/miri/src/shims/intrinsics/mod.rs b/src/tools/miri/src/shims/intrinsics/mod.rs
index e34fb118f72..df2761bfaf4 100644
--- a/src/tools/miri/src/shims/intrinsics/mod.rs
+++ b/src/tools/miri/src/shims/intrinsics/mod.rs
@@ -108,12 +108,12 @@ pub trait EvalContextExt<'mir, 'tcx: 'mir>: crate::MiriInterpCxExt<'mir, 'tcx> {
             "volatile_load" => {
                 let [place] = check_arg_count(args)?;
                 let place = this.deref_pointer(place)?;
-                this.copy_op(&place, dest, /*allow_transmute*/ false)?;
+                this.copy_op(&place, dest)?;
             }
             "volatile_store" => {
                 let [place, dest] = check_arg_count(args)?;
                 let place = this.deref_pointer(place)?;
-                this.copy_op(dest, &place, /*allow_transmute*/ false)?;
+                this.copy_op(dest, &place)?;
             }
 
             "write_bytes" | "volatile_set_memory" => {
diff --git a/src/tools/miri/src/shims/x86/mod.rs b/src/tools/miri/src/shims/x86/mod.rs
index 1aaf820f460..b24ea8aec84 100644
--- a/src/tools/miri/src/shims/x86/mod.rs
+++ b/src/tools/miri/src/shims/x86/mod.rs
@@ -299,7 +299,6 @@ fn bin_op_simd_float_first<'tcx, F: rustc_apfloat::Float>(
         this.copy_op(
             &this.project_index(&left, i)?,
             &this.project_index(&dest, i)?,
-            /*allow_transmute*/ false,
         )?;
     }
 
@@ -424,7 +423,6 @@ fn unary_op_ss<'tcx>(
         this.copy_op(
             &this.project_index(&op, i)?,
             &this.project_index(&dest, i)?,
-            /*allow_transmute*/ false,
         )?;
     }
 
@@ -484,7 +482,6 @@ fn round_first<'tcx, F: rustc_apfloat::Float>(
         this.copy_op(
             &this.project_index(&left, i)?,
             &this.project_index(&dest, i)?,
-            /*allow_transmute*/ false,
         )?;
     }
 
diff --git a/src/tools/miri/src/shims/x86/sse.rs b/src/tools/miri/src/shims/x86/sse.rs
index 1e9afc1e9e0..9fb947cb2a3 100644
--- a/src/tools/miri/src/shims/x86/sse.rs
+++ b/src/tools/miri/src/shims/x86/sse.rs
@@ -211,7 +211,6 @@ pub(super) trait EvalContextExt<'mir, 'tcx: 'mir>:
                     this.copy_op(
                         &this.project_index(&left, i)?,
                         &this.project_index(&dest, i)?,
-                        /*allow_transmute*/ false,
                     )?;
                 }
             }
diff --git a/src/tools/miri/src/shims/x86/sse2.rs b/src/tools/miri/src/shims/x86/sse2.rs
index 49bf7547ab0..e5c8267320a 100644
--- a/src/tools/miri/src/shims/x86/sse2.rs
+++ b/src/tools/miri/src/shims/x86/sse2.rs
@@ -443,7 +443,6 @@ pub(super) trait EvalContextExt<'mir, 'tcx: 'mir>:
                     this.copy_op(
                         &this.project_index(&op, i)?,
                         &this.project_index(&dest, i)?,
-                        /*allow_transmute*/ false,
                     )?;
                 }
             }
@@ -584,7 +583,6 @@ pub(super) trait EvalContextExt<'mir, 'tcx: 'mir>:
                     this.copy_op(
                         &this.project_index(&left, i)?,
                         &this.project_index(&dest, i)?,
-                        /*allow_transmute*/ false,
                     )?;
                 }
             }
diff --git a/src/tools/miri/src/shims/x86/sse41.rs b/src/tools/miri/src/shims/x86/sse41.rs
index 67bb63f0a3d..2abd10fa7a7 100644
--- a/src/tools/miri/src/shims/x86/sse41.rs
+++ b/src/tools/miri/src/shims/x86/sse41.rs
@@ -60,7 +60,6 @@ pub(super) trait EvalContextExt<'mir, 'tcx: 'mir>:
                         this.copy_op(
                             &this.project_index(&left, i)?,
                             &dest,
-                            /*allow_transmute*/ false,
                         )?;
                     }
                 }