tract_hir/ops/array/
constant_of_shape.rs

1use crate::infer::*;
2use crate::internal::*;
3
4#[derive(Debug, Clone, new, Hash)]
5pub struct ConstantOfShape {
6    scalar: Arc<Tensor>,
7}
8
9
10
11impl Expansion for ConstantOfShape {
12    fn name(&self) -> StaticName {
13        "ConstantOfShape".into()
14    }
15
16
17    fn rules<'r, 'p: 'r, 's: 'r>(
18        &'s self,
19        s: &mut Solver<'r>,
20        inputs: &'p [TensorProxy],
21        outputs: &'p [TensorProxy],
22    ) -> InferenceResult {
23        check_input_arity(inputs, 1)?;
24        check_output_arity(outputs, 1)?;
25        s.equals(&outputs[0].datum_type, self.scalar.datum_type())?;
26        s.equals(&inputs[0].rank, 1)?;
27        s.equals(&inputs[0].shape[0], outputs[0].rank.bex().to_dim())?;
28        s.given(&inputs[0].value, move |s, shape| {
29            let shape = shape.cast_to::<TDim>()?;
30            let shape = shape.as_slice::<TDim>()?;
31            for (axis, dim) in shape.iter().enumerate() {
32                s.equals(&outputs[0].shape[axis], dim)?;
33            }
34            Ok(())
35        })?;
36        /* does not work .value assumes ints
37        s.given(&outputs[0].rank, move |s, rank| {
38            for axis in 0..rank as usize {
39                s.equals(&outputs[0].shape[axis], &inputs[0].value[axis].bex())?;
40            }
41            Ok(())
42        })?;
43        */
44        Ok(())
45    }
46
47    fn wire(
48        &self,
49        prefix: &str,
50        target: &mut TypedModel,
51        inputs: &[OutletId],
52    ) -> TractResult<TVec<OutletId>> {
53        if let Some(shape) = target.outlet_fact(inputs[0])?.konst.clone() {
54            let shape = shape.cast_to::<TDim>()?;
55            let shape = shape.as_slice::<TDim>()?;
56            let scalar = target.add_const(format!("{prefix}.scalar"), self.scalar.clone())?;
57            let op = tract_core::ops::array::MultiBroadcastTo::new(shape.into());
58            return target.wire_node(prefix, op, &[scalar]);
59        }
60        bail!("shape input is variable")
61    }
62}