ruby/internal
Peter Zhu abff5f6203 Move classpath to rb_classext_t
This commit moves the classpath (and tmp_classpath) from instance
variables to the rb_classext_t. This improves performance as we no
longer need to set an instance variable when assigning a classpath to
a class.

I benchmarked with the following script:

```ruby
name = :MyClass

puts(Benchmark.measure do
  10_000_000.times do |i|
    Object.const_set(name, Class.new)
    Object.send(:remove_const, name)
  end
end)
```

Before this patch:

```
  5.440119   0.025264   5.465383 (  5.467105)
```

After this patch:

```
  4.889646   0.028325   4.917971 (  4.942678)
```
2023-01-11 11:06:58 -05:00
..
2022-12-17 14:51:49 -08:00
2023-01-11 11:06:58 -05:00
2022-12-02 01:31:27 +09:00
2022-11-02 11:03:21 -04:00
2022-10-21 14:56:48 -07:00