tract_core/ops/einsum/
optimize.rs

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
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
use std::ops::Deref;

use kernel_selection::wire_packing;
use tract_itertools::{izip, multiunzip};

use super::*;
use crate::ops::cast::cast;
use crate::ops::math::add;
use crate::ops::matmul::optimized::{
    AddMatMulGeometry, MapOutputAxisToInput, OptMatMul, ProtoFusedSpec,
};
use crate::ops::matmul::quant::{
    combine_scales, compensate_zero_points, requant, wire_ensure_q8_flavour,
};
use crate::ops::nn::{Reduce, Reducer};

#[allow(clippy::large_enum_variant)]
pub enum AxesOrPatch<'a> {
    Annotated(EinSumAnnotatedAsMatMul<'a>),
    Patch(TypedModelPatch),
    NotAMatMul(&'a Axis),
}

pub struct EinSumAnnotatedAsMatMul<'a> {
    pub op: &'a EinSum,
    pub m_axis: &'a Axis,
    pub k_axis: &'a Axis,
    pub n_axis: &'a Axis,
    pub m: TDim,
    pub k: TDim,
    pub n: TDim,
}

impl EinSumAnnotatedAsMatMul<'_> {
    pub fn a_m(&self) -> usize {
        self.m_axis.inputs[0][0]
    }
    pub fn a_k(&self) -> usize {
        self.k_axis.inputs[0][0]
    }
    pub fn b_k(&self) -> usize {
        self.k_axis.inputs[1][0]
    }
    pub fn b_n(&self) -> usize {
        self.n_axis.inputs[1][0]
    }
    pub fn c_m(&self) -> usize {
        self.m_axis.outputs[0][0]
    }
    pub fn c_n(&self) -> usize {
        self.n_axis.outputs[0][0]
    }
}

impl Deref for EinSumAnnotatedAsMatMul<'_> {
    type Target = EinSum;
    fn deref(&self) -> &Self::Target {
        self.op
    }
}

pub(crate) fn optimize(
    op: &EinSum,
    model: &TypedModel,
    node: &TypedNode,
) -> TractResult<Option<TypedModelPatch>> {
    if (op.q_params.is_none() && node.inputs.len() != 2)
        || (op.q_params.is_some() && node.inputs.len() != 9)
    {
        return Ok(None);
    }
    let annotated = match ensure_mkn_axes(op, model, node)? {
        AxesOrPatch::Annotated(op) => op,
        AxesOrPatch::Patch(p) => return Ok(Some(p)),
        AxesOrPatch::NotAMatMul(_) => return Ok(None),
    };
    if op.q_params.is_none() {
        optimized_mat_mul(model, node, &annotated).context("Translating to OptMatMul")
    } else {
        dequant(model, node, annotated).context("Dequantize")
    }
}

pub(crate) fn ensure_mkn_axes<'a>(
    op: &'a EinSum,
    model: &TypedModel,
    node: &TypedNode,
) -> TractResult<AxesOrPatch<'a>> {
    let input_facts = model.node_input_facts(node.id)?;
    let input_shapes = op.actual_input_shapes_from_facts(&input_facts)?;
    let output_shape = super::eval::output_shape(&op.axes, &input_shapes)?;
    let k_axes: TVec<&Axis> = op
        .axes
        .iter_all_axes()
        // Filter possible candidates (should be one time in each inputs but not in output)
        .filter(|a| {
            a.inputs[0].len() == 1 && a.inputs[1].len() == 1 && a.outputs[0].len() == 0
        })
    .collect();

    let non_trivial_k_axis = k_axes
        .iter()
        .filter(|a| {
            !input_shapes[0][a.inputs[0][0]].is_one() || !input_shapes[1][a.inputs[1][0]].is_one()
        })
        .collect::<TVec<_>>();

    let k_axis = if non_trivial_k_axis.len() > 1 {
        // TODO: handle case where multiple consecutive k in the same order in both input.
        bail!("Multiple k-axis candidate found");
    } else {
        non_trivial_k_axis.first().copied().or_else(|| k_axes.first()).copied()
    };
    let Some(k_axis) = k_axis else {
        return Ok(AxesOrPatch::Patch(inject_k_axis(op, model, node)?));
    };
    let m_axis = op
        .axes
        .iter_all_axes()
        .filter(|a| {
            a.inputs[0].len() == 1
                && (a.inputs[1].len() == 0 || input_shapes[1][a.inputs[1][0]].is_one())
                && a.outputs[0].len() == 1
        })
        .max_by_key(|a| output_shape[a.outputs[0][0]].as_i64().unwrap_or(i64::MAX));
    let Some(m_axis) = m_axis else {
        return Ok(AxesOrPatch::Patch(inject_m_or_n_axis(op, model, node, false, &[k_axis])?));
    };
    let n_axis = op
        .axes
        .iter_all_axes()
        .filter(|a| {
            (a.inputs[0].len() == 0 || input_shapes[0][a.inputs[0][0]].is_one())
                && a.inputs[1].len() == 1
                && a.outputs[0].len() == 1
        })
        .max_by_key(|a| output_shape[a.outputs[0][0]].as_i64().unwrap_or(i64::MAX));
    let Some(n_axis) = n_axis else {
        return Ok(AxesOrPatch::Patch(inject_m_or_n_axis(
            op,
            model,
            node,
            true,
            &[k_axis, m_axis],
        )?));
    };
    for axis in op.axes.iter_all_axes() {
        let one = TDim::one();
        let in_left =
            axis.inputs[0].first().map(|pos| &input_shapes[0][*pos]).unwrap_or(&one) != &one;
        let in_right =
            axis.inputs[1].first().map(|pos| &input_shapes[1][*pos]).unwrap_or(&one) != &one;
        let in_out = axis.outputs[0].first().map(|pos| &output_shape[*pos]).unwrap_or(&one) != &one;
        if (in_left ^ in_right) && !in_out {
            return Ok(AxesOrPatch::NotAMatMul(axis));
        }
    }
    let m = input_shapes[0][m_axis.inputs[0][0]].clone();
    let k = input_shapes[0][k_axis.inputs[0][0]].clone();
    let n = input_shapes[1][n_axis.inputs[1][0]].clone();
    Ok(AxesOrPatch::Annotated(EinSumAnnotatedAsMatMul { op, m_axis, k_axis, n_axis, m, k, n }))
}

pub(super) fn inject_k_axis(
    op: &EinSum,
    model: &TypedModel,
    node: &TypedNode,
) -> TractResult<TypedModelPatch> {
    let mut new_axes = op.axes.clone();
    let name = &node.name;
    let mut patch = TypedModelPatch::new("inject k axis");
    let mut wire = patch.taps(model, &node.inputs)?;
    let repr = new_axes.available_label();
    new_axes = new_axes.with_extra_axis(repr, InOut::In(0), 0)?.with_extra_axis_occurency(
        repr,
        InOut::In(1),
        0,
    )?;
    wire[0] = patch.wire_node(format!("{name}.add_k.0"), AxisOp::Add(0), &[wire[0]])?[0];
    wire[1] = patch.wire_node(format!("{name}.add_k.1"), AxisOp::Add(0), &[wire[1]])?[0];
    wire = patch.wire_node(&node.name, EinSum { axes: new_axes, ..op.clone() }, &wire)?;
    patch.shunt_outside(model, node.id.into(), wire[0])?;
    Ok(patch)
}

pub(super) fn inject_m_or_n_axis(
    op: &EinSum,
    model: &TypedModel,
    node: &TypedNode,
    is_n: bool,
    exclude: &[&Axis],
) -> TractResult<TypedModelPatch> {
    let input_facts = model.node_input_facts(node.id)?;
    let input_shapes = op.actual_input_shapes_from_facts(&input_facts)?;
    let input_to_fix = is_n as usize;
    let label = if is_n { "n" } else { "m" };
    let quasi_m_or_n_axis = op.axes.iter_all_axes().filter(|a| !exclude.contains(a)).find(|a| {
        (a.inputs[1 - input_to_fix].len() == 0
            || input_shapes[1 - input_to_fix][a.inputs[1 - input_to_fix][0]].is_one())
            && (a.inputs[input_to_fix].len() == 1 || a.outputs[0].len() == 1)
    });
    let name = &node.name;
    let mut patch = TypedModelPatch::new("Injecting m or n axis");
    let mut wire = patch.taps(model, &node.inputs)?;
    if let Some(axis) = quasi_m_or_n_axis {
        if axis.inputs[input_to_fix].len() == 1 {
            let new_axes =
                op.axes.clone().with_extra_axis('$', InOut::Out(0), 0)?.linking(axis.repr, '$')?;
            wire = patch.wire_node(
                format!("{name}.einsum"),
                EinSum { axes: new_axes, ..op.clone() },
                &wire,
            )?;
            wire = patch.wire_node(&node.name, AxisOp::Rm(0), &wire)?;
        } else {
            let new_axes = op
                .axes
                .clone()
                .with_extra_axis('$', InOut::In(input_to_fix), 0)?
                .linking(axis.repr, '$')?;
            wire[input_to_fix] = patch.wire_node(
                format!("{name}.add_{label}"),
                AxisOp::Add(0),
                &[wire[input_to_fix]],
            )?[0];
            wire = patch.wire_node(&node.name, EinSum { axes: new_axes, ..op.clone() }, &wire)?;
        }
    } else {
        let repr = op.axes.available_label();
        let new_axes = op
            .axes
            .clone()
            .with_extra_axis(repr, InOut::In(input_to_fix), 0)?
            .with_extra_axis('$', InOut::Out(0), 0)?
            .linking(repr, '$')?;
        wire[input_to_fix] = patch.wire_node(
            format!("{name}.add_{label}"),
            AxisOp::Add(0),
            &[wire[input_to_fix]],
        )?[0];
        wire = patch.wire_node(
            format!("{name}.einsum"),
            EinSum { axes: new_axes, ..op.clone() },
            &wire,
        )?;
        wire = patch.wire_node(&node.name, AxisOp::Rm(0), &wire)?;
    }
    patch.shunt_outside(model, node.id.into(), wire[0])?;
    Ok(patch)
}

fn wire_axes_fix(
    patch: &mut TypedModelPatch,
    name: &str,
    var: &str,
    mapping: &AxesMapping,
    mut outlet: TVec<OutletId>,
) -> TractResult<TVec<OutletId>> {
    for (ix, axis_op) in mapping.translate_to_axis_ops()?.into_iter().enumerate() {
        outlet = patch.wire_node(format!("{name}.fix_{var}.{ix})"), axis_op, &outlet)?;
    }
    Ok(outlet)
}

fn dequant(
    model: &TypedModel,
    node: &TypedNode,
    op: EinSumAnnotatedAsMatMul,
) -> TractResult<Option<TypedModelPatch>> {
    let name = &node.name;
    let mut patch = TypedModelPatch::new("Dequantizing einsum");

    let mut taps = patch.taps(model, &node.inputs)?;
    for ab in [0, 1] {
        let scale_input = 4 + ab * 2;
        if !patch.outlet_fact(taps[scale_input])?.shape.volume().is_one() {
            let q_axis_in_output = op.axes.axis((InOut::In(scale_input), 0))?.outputs[0][0];
            let output_rank = node.outputs[0].fact.rank();
            for i in 1..(output_rank - q_axis_in_output) {
                taps[scale_input] = patch.wire_node(
                    format!("{name}.scale_input{ab}_axis_fix_{i}"),
                    AxisOp::Add(i),
                    &[taps[scale_input]],
                )?[0];
            }
        }
    }

    let [mut a, mut b, bias, mut a0, a_scale, mut b0, b_scale, c0, c_scale] = *taps else {
        bail!("Expect exactly 9 inputs")
    };

    wire_ensure_q8_flavour(&mut patch, &node.name, &mut a, "a", &mut a0, i8::datum_type())?;
    wire_ensure_q8_flavour(&mut patch, &node.name, &mut b, "b", &mut b0, i8::datum_type())?;

    let mut output = patch.wire_node(
        &node.name,
        EinSum {
            q_params: None,
            axes: op.axes.extract_sub_mapping(&[0, 1], &[0])?,
            operating_dt: op.operating_dt,
        },
        &[a, b],
    )?;

    let a_i32 = patch.wire_node(format!("{name}.a_as_i32"), cast(i32::datum_type()), &[a])?[0];
    let b_i32 = patch.wire_node(format!("{name}.b_as_i32"), cast(i32::datum_type()), &[b])?[0];
    let sum_a = patch.wire_node(
        format!("{name}.sum_a"),
        Reduce::new(tvec!(op.k_axis.inputs[0][0]), Reducer::Sum),
        &[a_i32],
    )?;
    let sum_b = patch.wire_node(
        format!("{name}.sum_b"),
        Reduce::new(tvec!(op.k_axis.inputs[1][0]), Reducer::Sum),
        &[b_i32],
    )?;

    let sum_a =
        wire_axes_fix(&mut patch, name, "sum_a", &op.axes.extract_sub_mapping(&[0], &[0])?, sum_a)?;
    let sum_b =
        wire_axes_fix(&mut patch, name, "sum_b", &op.axes.extract_sub_mapping(&[1], &[0])?, sum_b)?;
    let bias = tvec!(bias);
    let bias =
        wire_axes_fix(&mut patch, name, "bias", &op.axes.extract_sub_mapping(&[2], &[0])?, bias)?;

    let abc_scale = combine_scales(&mut patch, name, a_scale, b_scale, c_scale)?;

    output = patch.wire_node(format!("{name}.add_bias"), add(), &[output[0], bias[0]])?;

    let k = model.outlet_fact(node.inputs[0])?.shape[op.k_axis.inputs[0][0]].clone();
    let output = compensate_zero_points(&mut patch, name, output[0], k, a0, b0, sum_a[0], sum_b[0])
        .context("Zero point compensation")?;
    let output = requant(&mut patch, name, output, op.q_params.unwrap(), abc_scale, c0)?;
    patch.shunt_outside(model, node.id.into(), output)?;
    Ok(Some(patch))
}

fn optimized_mat_mul(
    model: &TypedModel,
    node: &TypedNode,
    op: &EinSumAnnotatedAsMatMul,
) -> TractResult<Option<TypedModelPatch>> {
    let input_facts = model.node_input_facts(node.id)?;
    let input_shapes = op.actual_input_shapes_from_facts(&input_facts)?;
    let must_transpose = match (op.m.as_i64(), op.n.as_i64()) {
        (Some(m), Some(n)) => m < n,
        (None, Some(n)) => n >= 8,
        _ => false,
    };
    if must_transpose {
        let expr = op
            .op
            .axes
            .iter_all_axes()
            .map(|axis| {
                let mut axis = axis.clone();
                axis.inputs.swap(0, 1);
                axis
            })
            .collect::<TVec<Axis>>();
        return TypedModelPatch::replace_single_op(
            model,
            node,
            &[node.inputs[1], node.inputs[0]],
            EinSum { axes: AxesMapping::new(node.inputs.len(), 1, expr)?, ..op.op.clone() },
        )
        .map(Some);
    }

    let mut patch = TypedModelPatch::new("Einsum to OptMatMul");
    let name = &node.name;
    let taps = patch.taps(model, &node.inputs)?;
    let (a, b, mmms, mode_picker) = wire_packing(&mut patch, name, &taps[0..2], op)?;

    let mut c_to_a_axis_mapping = tvec!();
    let mut c_to_b_axis_mapping = tvec!();
    for axis in op
        .op
        .axes
        .iter_all_axes()
        .filter(|&axis| ![op.m_axis, op.k_axis, op.n_axis].contains(&axis))
    {
        if let (&[c], &[a]) = (&*axis.outputs[0], &*axis.inputs[0]) {
            if input_shapes[0][a] != 1.to_dim() {
                let a = a - (a > op.a_m()) as usize - (a > op.a_k()) as usize;
                c_to_a_axis_mapping.push((c, a));
            }
        }
        if let (&[c], &[b]) = (&*axis.outputs[0], &*axis.inputs[1]) {
            if input_shapes[1][b] != 1.to_dim() {
                let b = b - (b > op.b_n()) as usize - (b > op.b_k()) as usize;
                c_to_b_axis_mapping.push((c, b));
            }
        }
    }

    let c_fact = op.output_facts(&input_facts)?.remove(0);
    let geo = AddMatMulGeometry {
        k: op.k.clone(),
        c_to_a_axis_mapping: MapOutputAxisToInput(c_to_a_axis_mapping),
        c_to_b_axis_mapping: MapOutputAxisToInput(c_to_b_axis_mapping),
    };
    let (mmms, packings, extractor): (Vec<_>, Vec<_>, Vec<_>) = multiunzip(mmms);
    let outputs = mmms.iter().map(|mmm| unsafe { mmm.c_view(op.c_m(), op.c_n()) }).collect();
    let trivial_packing =
        mmms.len() == 1 && packings[0] == 0 && patch.outlet_fact(a)?.opaque_fact.is_none();
    let opt = OptMatMul::new(
        mmms,
        mode_picker,
        c_fact,
        op.c_m(),
        op.c_n(),
        vec![
            ProtoFusedSpec::AddMatMul {
                geo,
                a: 0,
                b: 1,
                packings: izip!(packings, extractor).collect_vec(),
            },
            ProtoFusedSpec::Store(outputs),
        ],
        trivial_packing,
    )
    .context("Creating OptMatMul")?;
    let output = patch.wire_node(name, opt, &[a, b])?[0];
    patch.shunt_outside(model, node.id.into(), output)?;
    Ok(Some(patch))
}