reduce code duplication

Author: RalfJung

compiler/rustc_const_eval/src/interpret/operand.rs

@@ -284,15 +284,18 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
             Abi::Scalar(s) if force => Some(s.primitive()),
             _ => None,
         };
-        let number_may_have_provenance = !M::enforce_number_no_provenance(self);
+        let read_provenance = |s: abi::Primitive, size| {
+            // Should be just `s.is_ptr()`, but we support a Miri flag that accepts more
+            // questionable ptr-int transmutes.
+            let number_may_have_provenance = !M::enforce_number_no_provenance(self);
+            s.is_ptr() || (number_may_have_provenance && size == self.pointer_size())
+        };
         if let Some(s) = scalar_layout {
             //FIXME(#96185): let size = s.size(self);
             //FIXME(#96185): assert_eq!(size, mplace.layout.size, "abi::Scalar size does not match layout size");
             let size = mplace.layout.size; //FIXME(#96185): remove this line
-            let scalar = alloc.read_scalar(
-                alloc_range(Size::ZERO, size),
-                s.is_ptr() || (number_may_have_provenance && size == self.pointer_size()),
-            )?;
+            let scalar =
+                alloc.read_scalar(alloc_range(Size::ZERO, size), read_provenance(s, size))?;
             return Ok(Some(ImmTy { imm: scalar.into(), layout: mplace.layout }));
         }
         let scalar_pair_layout = match mplace.layout.abi {
@@ -310,14 +313,10 @@ impl<'mir, 'tcx: 'mir, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
             let (a_size, b_size) = (a.size(self), b.size(self));
             let b_offset = a_size.align_to(b.align(self).abi);
             assert!(b_offset.bytes() > 0); // in `operand_field` we use the offset to tell apart the fields
-            let a_val = alloc.read_scalar(
-                alloc_range(Size::ZERO, a_size),
-                a.is_ptr() || (number_may_have_provenance && a_size == self.pointer_size()),
-            )?;
-            let b_val = alloc.read_scalar(
-                alloc_range(b_offset, b_size),
-                b.is_ptr() || (number_may_have_provenance && b_size == self.pointer_size()),
-            )?;
+            let a_val =
+                alloc.read_scalar(alloc_range(Size::ZERO, a_size), read_provenance(a, a_size))?;
+            let b_val =
+                alloc.read_scalar(alloc_range(b_offset, b_size), read_provenance(b, b_size))?;
             return Ok(Some(ImmTy {
                 imm: Immediate::ScalarPair(a_val, b_val),
                 layout: mplace.layout,