Fix clippy warnings

Author: wks

src/util/address.rs

@@ -503,7 +503,14 @@ impl ObjectReference {
         NonZeroUsize::new(addr.0).map(ObjectReference)
     }
 
-    /// Like `from_raw_address`, but assume `addr` is not zero.
+    /// Like `from_raw_address`, but assume `addr` is not zero.  This can be used to elide a check
+    /// against zero for performance-critical code.
+    ///
+    /// # Safety
+    ///
+    /// This method assumes `addr` is not zero.  It should only be used in cases where we know at
+    /// compile time that the input cannot be zero.  For example, if we compute the address by
+    /// adding a positive offset to a non-zero address, we know the result must not be zero.
     pub unsafe fn from_raw_address_unchecked(addr: Address) -> ObjectReference {
         debug_assert!(!addr.is_zero());
         ObjectReference(NonZeroUsize::new_unchecked(addr.0))

src/util/metadata/vo_bit/mod.rs

@@ -100,9 +100,7 @@ pub fn is_vo_bit_set<VM: VMBinding>(object: ObjectReference) -> bool {
 /// Check if an address can be turned directly into an object reference using the VO bit.
 /// If so, return `Some(object)`. Otherwise return `None`.
 pub fn is_vo_bit_set_for_addr<VM: VMBinding>(address: Address) -> Option<ObjectReference> {
-    let Some(potential_object) = ObjectReference::from_raw_address(address) else {
-        return None;
-    };
+    let potential_object = ObjectReference::from_raw_address(address)?;
 
     let addr = potential_object.to_address::<VM>();
 
@@ -126,9 +124,7 @@ pub fn is_vo_bit_set_for_addr<VM: VMBinding>(address: Address) -> Option<ObjectR
 ///
 /// This is unsafe: check the comment on `side_metadata::load`
 pub unsafe fn is_vo_bit_set_unsafe<VM: VMBinding>(address: Address) -> Option<ObjectReference> {
-    let Some(potential_object) = ObjectReference::from_raw_address(address) else {
-        return None;
-    };
+    let potential_object = ObjectReference::from_raw_address(address)?;
 
     let addr = potential_object.to_address::<VM>();