Function insert

cranelift/codegen/src/ir/constant.rs:284–289

()

    #[test]
    fn insert() {
        let mut sut = ConstantPool::new();
        sut.insert(vec![1, 2, 3].into());
        sut.insert(vec![4, 5, 6].into());
        assert_eq!(sut.len(), 2);
    }

    #[test]
    fn insert_duplicate() {