1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62

use crate::{kernel, ops::to_device, tensor::JitTensor, JitBackend, Runtime};
use burn_tensor::{
    backend::BackendBridge,
    ops::{FloatElem, FloatTensor},
};
use core::marker::PhantomData;

/// Handle precision conversion for the jit backend.
#[derive(Debug)]
pub struct PrecisionBridge<R> {
    _runtime: PhantomData<R>,
}

impl<ROrigin, RTarget> BackendBridge<JitBackend<ROrigin>> for PrecisionBridge<RTarget>
where
    ROrigin: Runtime,
    RTarget:
        Runtime<Device = ROrigin::Device, Server = ROrigin::Server, Channel = ROrigin::Channel>,
{
    type Target = JitBackend<RTarget>;

    fn into_target<const D: usize>(
        tensor: FloatTensor<JitBackend<ROrigin>, D>,
        device: Option<burn_tensor::Device<Self::Target>>,
    ) -> FloatTensor<Self::Target, D> {
        let tensor = kernel::cast::<
            ROrigin,
            FloatElem<JitBackend<ROrigin>>,
            FloatElem<JitBackend<RTarget>>,
            D,
        >(tensor);

        // The line below does the backend type cast.
        let tensor = JitTensor::new(tensor.client, tensor.device, tensor.shape, tensor.handle);

        if let Some(device) = &device {
            to_device(tensor, device)
        } else {
            tensor
        }
    }

    fn from_target<const D: usize>(
        tensor: FloatTensor<Self::Target, D>,
        device: Option<burn_tensor::Device<JitBackend<ROrigin>>>,
    ) -> FloatTensor<JitBackend<ROrigin>, D> {
        let tensor = kernel::cast::<
            RTarget,
            FloatElem<JitBackend<RTarget>>,
            FloatElem<JitBackend<ROrigin>>,
            D,
        >(tensor);
        // The line below does the backend type cast.
        let tensor = JitTensor::new(tensor.client, tensor.device, tensor.shape, tensor.handle);

        if let Some(device) = &device {
            to_device(tensor, device)
        } else {
            tensor
        }
    }
}