Add ir::Types::lane_of as an alias of lane_type to be used in typevar constraints;

cranelift/codegen/src/ir/instructions.rs

@@ -498,7 +498,7 @@ enum OperandConstraint {
     /// This operand is the same type as the controlling type variable.
     Same,
 
-    /// This operand is `ctrlType.lane_type()`.
+    /// This operand is `ctrlType.lane_of()`.
     LaneOf,
 
     /// This operand is `ctrlType.as_bool()`.
@@ -527,7 +527,7 @@ impl OperandConstraint {
             Concrete(t) => Bound(t),
             Free(vts) => ResolvedConstraint::Free(TYPE_SETS[vts as usize]),
             Same => Bound(ctrl_type),
-            LaneOf => Bound(ctrl_type.lane_type()),
+            LaneOf => Bound(ctrl_type.lane_of()),
             AsBool => Bound(ctrl_type.as_bool()),
             HalfWidth => Bound(ctrl_type.half_width().expect("invalid type for half_width")),
             DoubleWidth => Bound(

cranelift/codegen/src/ir/types.rs

@@ -44,10 +44,17 @@ impl Type {
         if self.0 < VECTOR_BASE {
             self
         } else {
-            Type(LANE_BASE | (self.0 & 0x0f))
+            Self(LANE_BASE | (self.0 & 0x0f))
         }
     }
 
+    /// The type transformation that returns the lane type of a type variable; it is just a
+    /// renaming of lane_type() to be used in context where we think in terms of type variable
+    /// transformations.
+    pub fn lane_of(self) -> Self {
+        self.lane_type()
+    }
+
     /// Get log_2 of the number of bits in a lane.
     pub fn log2_lane_bits(self) -> u8 {
         match self.lane_type() {