[PATCH vkd3d v7 4/6] vkd3d-shader/hlsl: Perform a copy propagation pass.

[Matteo Bruni]

On Thu, Nov 18, 2021 at 6:43 PM Zebediah Figura (she/her)
<zfigura at codeweavers.com> wrote:
>
> On 11/18/21 11:28, Matteo Bruni wrote:
> > This and copy_propagation_transform_block() are a bit of a
> > reimplementation of transform_ir(). It should be possible to extend
> > transform_ir() to handle this new pass instead.
> >
> > I'd introduce a struct like
> >
> > struct transform_pass
> > {
> >      bool (*initialize)(struct hlsl_ctx *hlsl_ctx, void **ctx);
> >      bool (*process_instruction)(void *ctx, struct hlsl_ir_node *, void *);
> >      void (*destroy)(void *ctx);
> > };
> >
> > and update transform_ir() and the existing passes to make use of it. I
> > imagine we could have some generic initialize() implementation simply
> > doing *ctx = hlsl_ctx; and an empty destroy() implementation to be
> > used when there is no particular context to carry around (like in the
> > existing passes).
> >
>
> Pretty much the whole point of transform_ir() is that it recursively
> iterates through CF blocks for cases where you don't care about
> transforming the CF blocks themselves. That's not the case here. What
> you're describing sounds to me like a framework that doesn't actually
> serve any purpose to its use case.

Well, transform_ir() could start calling process_instruction() for the
HLSL_IR_IF and HLSL_IR_LOOP instructions before recursing, allowing
the pass to do what it needs for those, and existing passes would keep
ignoring those instructions. Would that not be enough? Or are you
saying that transform_ir() should not become more complex?