Re: [PATCH v2 0/3] MR482: vkd3d-shader/hlsl: Fix infinite loops when applying copy-prop to swizzles.

[Zebediah Figura (＠zfigura)]

> 1 : A
> 2 : A = @1
> 3 : @1.x
>
> In this case @3 would call copy_propagation_get_value() on A.x and would get @1, without detecting that that is indeed the same node it is already using as swizzle->value. So it would return true, keeping copy-prop spinning.

Without thinking it through fully, that sounds like copy-prop is even more broken. Fundamentally we shouldn't be propagating a store that happens *after* the load we're reaching through.

After all, given

```
1: A
2: idk lol
3: A = @2
4: @1.x
```

the store at @3 should prevent us from replacing @4 with @2. Either that's not happening now, in which case we have bigger problems, or it is happening now, in which case why is that same logic not preventing the infinite loop?