Constant scheduling

• Now that constants are lowered to just memsets, they can be scheduled inside control flow just fine.

hercules_opt/src/gcm.rs

@@ -199,8 +199,6 @@ fn basic_blocks(
                 args: _,
             } => bbs[idx] = Some(control),
             Node::Parameter { index: _ } => bbs[idx] = Some(NodeID::new(0)),
-            Node::Constant { id: _ } => bbs[idx] = Some(NodeID::new(0)),
-            Node::DynamicConstant { id: _ } => bbs[idx] = Some(NodeID::new(0)),
             _ if function.nodes[idx].is_control() => bbs[idx] = Some(NodeID::new(idx)),
             _ => {}
         }