[naga] Calling a function accepting a ptr from within another function

[gents83]

I'm in a situation where I would like to call a function accepting a ptr from within another function.
But it fails to compile without much info

and inside another function I'm calling

But the error that I get is just: Function [44] 'my_function_name' is invalid

It seems that it should work, but the error doesn't give much info and it seems to not be able to validate the shader

[teoxoy]

let will load the value, you should use var.

[gents83]

I tried also with var but with no luck 😥

[teoxoy]

Same error message?

[gents83]

Adding maybe similar use case scenario - the situation is the following one:
I've following struct

struct RayData {
ray: Ray,
node_index: i32,
next_index: i32,
data_type: u32,
visibility_id: u32,
};

and a function

fn intersect_aabb(ray: ptr<function, Ray>, aabb_min: vec3, aabb_max: vec3) -> f32 { /* ... */ }

and it seems that naga today is complaining on:

let intersection = intersect_aabb(&data.ray, (*node).min, (*node).max);

while it seems to accept if I do something like:

var ray_copied = data.ray;
let intersection = intersect_aabb(&ray_copied, (*node).min, (*node).max);

data is also declared as a var data but it seems that ptr is not able to use to inner variables of a struct as ptr, but maybe is correct and it's me that I'm expecting something that should not work like that

[teoxoy]

struct RayData {
    ray: Ray,
};

struct Ray {
    data_type: u32,
};

fn main() {
    var data = RayData();
    let intersection = intersect_aabb(&data.ray);
}

fn intersect_aabb(ray: ptr<function, Ray>) -> f32 {
    return 0.0;
}

This compiles fine via naga cli on trunk. Could you provide a minimum reproducible example like the one above that doesn't?

[gents83]

Oh sorry, maybe I didn't clarity it.
It compiles/validate fine on my side too, but once used inside a compute pipeline it actually fails to be used 😅

[teoxoy]

It compiles/validate fine on my side too, but once used inside a compute pipeline it actually fails to be used

In what way does it fail to be used?

The original error you were getting was "Function [44] 'my_function_name' is invalid" which is a naga validation error; I'm confused 😅.

[gents83]

I'm usually validating my shaders at compile time with:

And it's successefully validated.
But at runtime - when calling the device.create_compute_pipeline() - it fails with that error :(

[gents83]

This is an example that validate correctly but than fails at runtime:

struct InnerContainer {
    inner_id: u32,
}
struct Container {
    id: u32,
    inner: InnerContainer,
};

fn id(c: ptr<function, Container>) -> u32 {
    return (*c).id;
}
fn inner_id(c: ptr<function, InnerContainer>) -> u32 {
    return (*c).inner_id;
}
fn first(c: ptr<function, Container>) -> u32 {
    return id(c);
}
fn second(c: ptr<function, Container>) -> u32 {
    return inner_id(&(*c).inner);
}

@compute
@workgroup_size(16, 16, 1)
fn main() {
    var global_var = Container(1u, InnerContainer(2u));
    let u = first(&global_var);
    let v = second(&global_var);
}

But this time the error is:
internal error: entered unreachable code: Expression [2] is not cached!

[teoxoy]

Ah, this is probably the same issue as #4517.