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
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166

#[allow(clippy::module_inception)]
mod conv;
mod depth_wise;
mod im2col;
mod lazy_im2col;
mod q_sum_b;

use crate::internal::*;

pub use self::im2col::Im2Col;
pub(crate) use self::q_sum_b::QSumB;
pub use self::conv::Conv;

#[derive(Debug, Copy, Clone, PartialEq, Eq, Hash, Default)]
pub enum KernelFormat {
    #[default]
    OIHW,
    HWIO,
    OHWI,
}

impl KernelFormat {
    pub fn h_axis(&self) -> usize {
        match self {
            KernelFormat::OIHW => 2,
            KernelFormat::HWIO => 0,
            KernelFormat::OHWI => 1,
        }
    }

    pub fn spatial_shape<'a, D>(&self, full_shape: &'a [D]) -> &'a [D] {
        &full_shape[self.h_axis()..][..full_shape.len() - 2]
    }

    pub fn hw<'a, D>(&self, full_shape: &'a [D]) -> &'a [D] {
        self.spatial_shape(full_shape)
    }

    pub fn i<'a, D>(&self, full_shape: &'a [D]) -> &'a D {
        match self {
            KernelFormat::OIHW => &full_shape[1],
            KernelFormat::HWIO => &full_shape[full_shape.len() - 2],
            KernelFormat::OHWI => &full_shape[full_shape.len() - 1],
        }
    }

    pub fn o_axis<D>(&self, full_shape: &[D]) -> usize {
        match self {
            KernelFormat::OIHW | KernelFormat::OHWI => 0,
            KernelFormat::HWIO => full_shape.len() - 1,
        }
    }

    pub fn o<'a, D>(&self, full_shape: &'a [D]) -> &'a D {
        &full_shape[self.o_axis(full_shape)]
    }

    pub fn input_channels<'s, D: DimLike>(
        &self,
        full_kernel_shape: &'s [D],
        group: usize,
    ) -> Cow<'s, D> {
        match self {
            KernelFormat::OIHW => Cow::Owned(self.i(full_kernel_shape).clone() * group),
            KernelFormat::HWIO | KernelFormat::OHWI => Cow::Borrowed(self.i(full_kernel_shape)),
        }
    }

    pub fn output_channels<'s, D: DimLike>(
        &self,
        full_kernel_shape: &'s [D],
        group: usize,
    ) -> Cow<'s, D> {
        match self {
            KernelFormat::OIHW => Cow::Borrowed(self.o(full_kernel_shape)),
            KernelFormat::HWIO | KernelFormat::OHWI => {
                Cow::Owned(self.o(full_kernel_shape).clone() * group)
            }
        }
    }

    pub fn kernel_as_group_o_i_h_w_ops(
        &self,
        full_shape: &[impl DimLike],
        group: usize,
    ) -> TVec<AxisOp> {
        let geo_rank = full_shape.len() - 2;
        match self {
            // g is on i
            KernelFormat::HWIO => {
                tvec!(
                    AxisOp::Reshape(
                        geo_rank,
                        tvec!(self.i(full_shape).to_dim()),
                        tvec!(group.to_dim(), self.i(full_shape).to_dim() / group),
                    ), // h w g i o
                    AxisOp::Move(geo_rank, 0),     // g h w i o
                    AxisOp::Move(geo_rank + 2, 1), // g o h w i
                    AxisOp::Move(geo_rank + 2, 2)
                ) // g o i h w
            }
            // g is on o
            KernelFormat::OIHW => {
                tvec!(AxisOp::Reshape(
                    0,
                    tvec!(self.o(full_shape).to_dim()),
                    tvec!(group.to_dim(), self.o(full_shape).to_dim() / group),
                ))
            }
            // g is on i
            KernelFormat::OHWI => {
                tvec!(
                    AxisOp::Reshape(
                        geo_rank + 1,
                        tvec!(self.i(full_shape).to_dim()),
                        tvec!(group.to_dim(), self.i(full_shape).to_dim() / group),
                    ), // o h w g i
                    AxisOp::Move(geo_rank + 1, 0), // g o h w i
                    AxisOp::Move(geo_rank + 2, 2)
                )
            }
        }
    }

    pub fn kernel_as_group_o_i_hw_ops(
        &self,
        full_shape: &[impl DimLike],
        group: usize,
    ) -> TVec<AxisOp> {
        let mut ops = self.kernel_as_group_o_i_h_w_ops(full_shape, group);
        if self.hw(full_shape).len() > 1 {
            ops.push(AxisOp::Reshape(
                3,
                self.hw(full_shape).iter().map(|t| t.to_dim()).collect(),
                tvec!(self.hw(full_shape).iter().map(|t| t.to_dim()).product()),
            ));
        }
        ops
    }

    pub fn kernel_as_group_o_ihw_ops(
        &self,
        full_shape: &[impl DimLike],
        group: usize,
    ) -> TVec<AxisOp> {
        let i = (self.input_channels(full_shape, group).into_owned() / group).to_dim();
        let hw = self.hw(full_shape).iter().map(|t| t.to_dim()).product::<TDim>();
        let mut ops = self.kernel_as_group_o_i_hw_ops(full_shape, group);
        ops.push(AxisOp::Reshape(2, tvec!(i.clone(), hw.clone()), tvec!(i * hw)));
        ops
    }

    pub fn kernel_as_group_o_i_hw(&self, kernel: &Tensor, group: usize) -> TractResult<Tensor> {
        let mut kernel = kernel.clone();
        let ops = self.kernel_as_group_o_i_hw_ops(kernel.shape(), group);
        for op in &ops {
            op.change_tensor(&mut kernel, false)?;
        }
        Ok(kernel)
    }

    pub fn kernel_as_group_o_ihw(&self, kernel: &Tensor, group: usize) -> TractResult<Tensor> {
        let group_o_i_hw = self.kernel_as_group_o_i_hw(kernel, group)?;
        Ok(group_o_i_hw.collapse_axis_with_next(2))
    }
}