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from typing import Optional, Tuple, List |
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import warnings |
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import math |
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import jittor as jt |
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from jittor import Var |
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from jittor.nn import Module, Linear, softmax, pad, linear, dropout |
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from jittor.init import xavier_uniform_, xavier_gauss_, constant_ |
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def _canonical_mask( |
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mask: Optional[Var], |
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mask_name: str, |
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other_type, |
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other_name: str, |
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target_type, |
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check_other: bool = True, |
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) -> Optional[Var]: |
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if mask is not None: |
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_mask_dtype = mask.dtype |
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_mask_is_float = mask.dtype == jt.float16 or mask.dtype == jt.float32 or mask.dtype == jt.float64 |
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if _mask_dtype != jt.bool and not _mask_is_float: |
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raise AssertionError( |
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f"only bool and floating types of {mask_name} are supported") |
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if check_other and other_type is not None: |
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if _mask_dtype != other_type: |
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warnings.warn( |
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f"Support for mismatched {mask_name} and {other_name} " |
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"is deprecated. Use same type for both instead.") |
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if not _mask_is_float: |
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# WARNING(514flowey): Check Here |
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new_mask = jt.zeros_like(mask, dtype=target_type) |
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new_mask[mask] = float("-inf") |
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mask = new_mask |
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return mask |
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def _none_or_dtype(input: Optional[Var]): |
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if input is None: |
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return None |
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elif isinstance(input, jt.Var): |
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return input.dtype |
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def baddbmm(input_var: jt.Var, |
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batch1: jt.Var, |
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batch2: jt.Var, |
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beta=1, |
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alpha=1) -> jt.Var: |
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# WARNING(514flowey): Check here |
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return beta * input_var + alpha * (batch1 @ batch2) |
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def scaled_dot_product_attention(query, |
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key, |
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value, |
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attn_mask=None, |
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dropout_p=0.0, |
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is_causal=False, |
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scale=None, |
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training=True) -> jt.Var: |
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# Efficient implementation equivalent to the following: |
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L, S = query.size(-2), key.size(-2) |
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scale_factor = 1 / math.sqrt(query.size(-1)) if scale is None else scale |
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attn_bias = jt.zeros(L, S, dtype=query.dtype) |
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if is_causal: |
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assert attn_mask is None |
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temp_mask = jt.ones(L, S, dtype=jt.bool).tril(diagonal=0) |
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attn_bias[jt.logical_not(temp_mask)] = float("-inf") |
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# attn_bias.to(query.dtype) |
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attn_bias = jt.array(attn_bias, query.dtype) |
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if attn_mask is not None: |
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if attn_mask.dtype == jt.bool: |
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attn_bias[jt.logical_not(temp_mask)] = float("-inf") |
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else: |
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attn_bias += attn_mask |
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attn_weight = query @ key.transpose(-2, -1) * scale_factor |
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attn_weight += attn_bias |
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attn_weight = softmax(attn_weight, dim=-1) |
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attn_weight = dropout(attn_weight, dropout_p, is_train=training) |
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return attn_weight @ value |
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def _mha_shape_check(query: Var, key: Var, value: Var, |
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key_padding_mask: Optional[Var], attn_mask: Optional[Var], |
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num_heads: int): |
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if query.dim() == 3: |
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is_batched = True |
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assert key.dim() == 3 and value.dim() == 3, \ |
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("For batched (3-D) `query`, expected `key` and `value` to be 3-D" |
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f" but found {key.dim()}-D and {value.dim()}-D Vars respectively") |
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if key_padding_mask is not None: |
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assert key_padding_mask.dim() == 2, \ |
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("For batched (3-D) `query`, expected `key_padding_mask` to be `None` or 2-D" |
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f" but found {key_padding_mask.dim()}-D Var instead") |
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if attn_mask is not None: |
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assert attn_mask.dim() in (2, 3), \ |
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("For batched (3-D) `query`, expected `attn_mask` to be `None`, 2-D or 3-D" |
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f" but found {attn_mask.dim()}-D Var instead") |
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elif query.dim() == 2: |
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is_batched = False |
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assert key.dim() == 2 and value.dim() == 2, \ |
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("For unbatched (2-D) `query`, expected `key` and `value` to be 2-D" |
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f" but found {key.dim()}-D and {value.dim()}-D Vars respectively") |
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if key_padding_mask is not None: |
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assert key_padding_mask.dim() == 1, \ |
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("For unbatched (2-D) `query`, expected `key_padding_mask` to be `None` or 1-D" |
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f" but found {key_padding_mask.dim()}-D Var instead") |
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if attn_mask is not None: |
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assert attn_mask.dim() in (2, 3), \ |
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("For unbatched (2-D) `query`, expected `attn_mask` to be `None`, 2-D or 3-D" |
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f" but found {attn_mask.dim()}-D Var instead") |
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if attn_mask.dim() == 3: |
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expected_shape = (num_heads, query.shape[0], key.shape[0]) |
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assert attn_mask.shape == expected_shape, \ |
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(f"Expected `attn_mask` shape to be {expected_shape} but got {attn_mask.shape}") |
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else: |
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raise AssertionError( |
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f"query should be unbatched 2D or batched 3D Var but received {query.dim()}-D query Var" |
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) |
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return is_batched |
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def _in_projection_packed( |
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q: Var, |
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k: Var, |
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v: Var, |
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w: Var, |
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b: Optional[Var] = None, |
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) -> List[Var]: |
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E = q.size(-1) |
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if k is v: |
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if q is k: |
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# self-attention |
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proj = linear(q, w, b) |
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# reshape to 3, E and not E, 3 is deliberate for better memory coalescing and keeping same order as chunk() |
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# proj = proj.unflatten(-1, (3, E)).unsqueeze(0).transpose(0, -2).squeeze(-2).contiguous() |
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nshape = proj.shape[:-1] + (3, E) |
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proj = proj.reshape(nshape).unsqueeze(0).transpose(0, |
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-2).squeeze(-2) |
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return proj[0], proj[1], proj[2] |
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else: |
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# encoder-decoder attention |
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w_q, w_kv = w.split([E, E * 2]) |
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if b is None: |
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b_q = b_kv = None |
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else: |
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b_q, b_kv = b.split([E, E * 2]) |
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q_proj = linear(q, w_q, b_q) |
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kv_proj = linear(k, w_kv, b_kv) |
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# reshape to 2, E and not E, 2 is deliberate for better memory coalescing and keeping same order as chunk() |
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# kv_proj = kv_proj.unflatten(-1, (2, E)).unsqueeze(0).transpose(0, -2).squeeze(-2).contiguous() |
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nshape = kv_proj.shape[:-1] + (2, E) |
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kv_proj = kv_proj.reshape(nshape).unsqueeze(0).transpose( |
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0, -2).squeeze(-2) |
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return (q_proj, kv_proj[0], kv_proj[1]) |
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else: |
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w_q, w_k, w_v = w.chunk(3) |
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if b is None: |
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b_q = b_k = b_v = None |
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else: |
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b_q, b_k, b_v = b.chunk(3) |
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return linear(q, w_q, b_q), linear(k, w_k, b_k), linear(v, w_v, b_v) |
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def _in_projection( |
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q: Var, |
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k: Var, |
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v: Var, |
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w_q: Var, |
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w_k: Var, |
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w_v: Var, |
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b_q: Optional[Var] = None, |
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b_k: Optional[Var] = None, |
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b_v: Optional[Var] = None, |
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) -> Tuple[Var, Var, Var]: |
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Eq, Ek, Ev = q.size(-1), k.size(-1), v.size(-1) |
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assert w_q.shape == ( |
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Eq, Eq |
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), f"expecting query weights shape of {(Eq, Eq)}, but got {w_q.shape}" |
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assert w_k.shape == ( |
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Eq, |
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Ek), f"expecting key weights shape of {(Eq, Ek)}, but got {w_k.shape}" |
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assert w_v.shape == ( |
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Eq, Ev |
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), f"expecting value weights shape of {(Eq, Ev)}, but got {w_v.shape}" |
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assert b_q is None or b_q.shape == ( |
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Eq, ), f"expecting query bias shape of {(Eq,)}, but got {b_q.shape}" |
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assert b_k is None or b_k.shape == ( |
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Eq, ), f"expecting key bias shape of {(Eq,)}, but got {b_k.shape}" |
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assert b_v is None or b_v.shape == ( |
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Eq, ), f"expecting value bias shape of {(Eq,)}, but got {b_v.shape}" |
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return linear(q, w_q, b_q), linear(k, w_k, b_k), linear(v, w_v, b_v) |
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def multi_head_attention_forward( |
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query: Var, |
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key: Var, |
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value: Var, |
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embed_dim_to_check: int, |
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num_heads: int, |
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in_proj_weight: Optional[Var], |
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in_proj_bias: Optional[Var], |
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bias_k: Optional[Var], |
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bias_v: Optional[Var], |
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add_zero_attn: bool, |
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dropout_p: float, |
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out_proj_weight: Var, |
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out_proj_bias: Optional[Var], |
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training: bool = True, |
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key_padding_mask: Optional[Var] = None, |
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need_weights: bool = True, |
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attn_mask: Optional[Var] = None, |
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use_separate_proj_weight: bool = False, |
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q_proj_weight: Optional[Var] = None, |
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k_proj_weight: Optional[Var] = None, |
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v_proj_weight: Optional[Var] = None, |
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static_k: Optional[Var] = None, |
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static_v: Optional[Var] = None, |
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average_attn_weights: bool = True, |
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is_causal: bool = False, |
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) -> Tuple[Var, Optional[Var]]: |
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is_batched = _mha_shape_check(query, key, value, key_padding_mask, |
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attn_mask, num_heads) |
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# For unbatched input, we unsqueeze at the expected batch-dim to pretend that the input |
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# is batched, run the computation and before returning squeeze the |
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# batch dimension so that the output doesn't carry this temporary batch dimension. |
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if not is_batched: |
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# unsqueeze if the input is unbatched |
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query = query.unsqueeze(1) |
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key = key.unsqueeze(1) |
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value = value.unsqueeze(1) |
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if key_padding_mask is not None: |
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key_padding_mask = key_padding_mask.unsqueeze(0) |
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# set up shape vars |
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tgt_len, bsz, embed_dim = query.shape |
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src_len, _, _ = key.shape |
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key_padding_mask = _canonical_mask(mask=key_padding_mask, |
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mask_name="key_padding_mask", |
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other_type=_none_or_dtype(attn_mask), |
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other_name="attn_mask", |
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target_type=query.dtype) |
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if is_causal and attn_mask is None: |
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raise RuntimeError( |
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"Need attn_mask if specifying the is_causal hint. " |
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"You may use the Transformer module method " |
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"`generate_square_subsequent_mask` to create this mask.") |
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if is_causal and key_padding_mask is None and not need_weights: |
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# when we have a kpm or need weights, we need attn_mask |
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# Otherwise, we use the is_causal hint go as is_causal |
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# indicator to SDPA. |
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attn_mask = None |
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else: |
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attn_mask = _canonical_mask( |
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mask=attn_mask, |
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mask_name="attn_mask", |
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other_type=None, |
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other_name="", |
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target_type=query.dtype, |
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check_other=False, |
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) |
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if key_padding_mask is not None: |
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# We have the attn_mask, and use that to merge kpm into it. |
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# Turn off use of is_causal hint, as the merged mask is no |
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# longer causal. |
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is_causal = False |
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assert embed_dim == embed_dim_to_check, \ |
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f"was expecting embedding dimension of {embed_dim_to_check}, but got {embed_dim}" |
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if isinstance(embed_dim, jt.Var): |
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# embed_dim can be a Var when JIT tracing |
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head_dim = embed_dim.div(num_heads, rounding_mode='trunc') |
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else: |
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head_dim = embed_dim // num_heads |
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assert head_dim * num_heads == embed_dim, f"embed_dim {embed_dim} not divisible by num_heads {num_heads}" |
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if use_separate_proj_weight: |
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# allow MHA to have different embedding dimensions when separate projection weights are used |
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assert key.shape[:2] == value.shape[:2], \ |
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f"key's sequence and batch dims {key.shape[:2]} do not match value's {value.shape[:2]}" |
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else: |
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assert key.shape == value.shape, f"key shape {key.shape} does not match value shape {value.shape}" |
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# |
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# compute in-projection |
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# |
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if not use_separate_proj_weight: |
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assert in_proj_weight is not None, "use_separate_proj_weight is False but in_proj_weight is None" |
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q, k, v = _in_projection_packed(query, key, value, in_proj_weight, |
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in_proj_bias) |
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else: |
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assert q_proj_weight is not None, "use_separate_proj_weight is True but q_proj_weight is None" |
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assert k_proj_weight is not None, "use_separate_proj_weight is True but k_proj_weight is None" |
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assert v_proj_weight is not None, "use_separate_proj_weight is True but v_proj_weight is None" |
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if in_proj_bias is None: |
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b_q = b_k = b_v = None |
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else: |
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b_q, b_k, b_v = in_proj_bias.chunk(3) |
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q, k, v = _in_projection(query, key, value, q_proj_weight, |
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k_proj_weight, v_proj_weight, b_q, b_k, b_v) |
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# prep attention mask |
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if attn_mask is not None: |
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# ensure attn_mask's dim is 3 |
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if attn_mask.dim() == 2: |
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correct_2d_size = (tgt_len, src_len) |
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if attn_mask.shape != correct_2d_size: |
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raise RuntimeError( |
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f"The shape of the 2D attn_mask is {attn_mask.shape}, but should be {correct_2d_size}." |
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) |
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attn_mask = attn_mask.unsqueeze(0) |
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elif attn_mask.dim() == 3: |
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correct_3d_size = (bsz * num_heads, tgt_len, src_len) |
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if attn_mask.shape != correct_3d_size: |
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raise RuntimeError( |
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f"The shape of the 3D attn_mask is {attn_mask.shape}, but should be {correct_3d_size}." |
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) |
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else: |
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raise RuntimeError( |
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f"attn_mask's dimension {attn_mask.dim()} is not supported") |
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# add bias along batch dimension (currently second) |
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if bias_k is not None and bias_v is not None: |
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assert static_k is None, "bias cannot be added to static key." |
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assert static_v is None, "bias cannot be added to static value." |
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k = jt.concat([k, bias_k.repeat(1, bsz, 1)]) |
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v = jt.concat([v, bias_v.repeat(1, bsz, 1)]) |
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if attn_mask is not None: |
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attn_mask = pad(attn_mask, (0, 1)) |
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if key_padding_mask is not None: |
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key_padding_mask = pad(key_padding_mask, (0, 1)) |
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else: |
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assert bias_k is None |
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assert bias_v is None |
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# |
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# reshape q, k, v for multihead attention and make em batch first |
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# |
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q = q.view(tgt_len, bsz * num_heads, head_dim).transpose(0, 1) |
|
|
|
if static_k is None: |
|
|
|
k = k.view(k.shape[0], bsz * num_heads, head_dim).transpose(0, 1) |
|
|
|
else: |
|
|
|
# TODO finish disentangling control flow so we don't do in-projections when statics are passed |
|
|
|
assert static_k.size(0) == bsz * num_heads, \ |
|
|
|
f"expecting static_k.size(0) of {bsz * num_heads}, but got {static_k.size(0)}" |
|
|
|
assert static_k.size(2) == head_dim, \ |
|
|
|
f"expecting static_k.size(2) of {head_dim}, but got {static_k.size(2)}" |
|
|
|
k = static_k |
|
|
|
if static_v is None: |
|
|
|
v = v.view(v.shape[0], bsz * num_heads, head_dim).transpose(0, 1) |
|
|
|
else: |
|
|
|
# TODO finish disentangling control flow so we don't do in-projections when statics are passed |
|
|
|
assert static_v.size(0) == bsz * num_heads, \ |
|
|
|
f"expecting static_v.size(0) of {bsz * num_heads}, but got {static_v.size(0)}" |
|
|
|
assert static_v.size(2) == head_dim, \ |
|
|
|
f"expecting static_v.size(2) of {head_dim}, but got {static_v.size(2)}" |
|
|
|
v = static_v |
|
|
|
|
|
|
|
# add zero attention along batch dimension (now first) |
|
|
|
if add_zero_attn: |
|
|
|
zero_attn_shape = (bsz * num_heads, 1, head_dim) |
|
|
|
k = jt.concat([k, jt.zeros(zero_attn_shape, dtype=k.dtype)], dim=1) |
|
|
|
v = jt.concat([v, jt.zeros(zero_attn_shape, dtype=v.dtype)], dim=1) |
|
|
|
if attn_mask is not None: |
|
|
|
attn_mask = pad(attn_mask, (0, 1)) |
|
|
|
if key_padding_mask is not None: |
|
|
|
key_padding_mask = pad(key_padding_mask, (0, 1)) |
|
|
|
|
|
|
|
# update source sequence length after adjustments |
|
|
|
src_len = k.size(1) |
|
|
|
|
|
|
|
# merge key padding and attention masks |
|
|
|
if key_padding_mask is not None: |
|
|
|
assert key_padding_mask.shape == (bsz, src_len), \ |
|
|
|
f"expecting key_padding_mask shape of {(bsz, src_len)}, but got {key_padding_mask.shape}" |
|
|
|
key_padding_mask = key_padding_mask.view(bsz, 1, 1, src_len). \ |
|
|
|
expand(-1, num_heads, -1, -1).reshape(bsz * num_heads, 1, src_len) |
|
|
|
if attn_mask is None: |
|
|
|
attn_mask = key_padding_mask |
|
|
|
else: |
|
|
|
attn_mask = attn_mask + key_padding_mask |
|
|
|
|
|
|
|
# adjust dropout probability |
|
|
|
if not training: |
|
|
|
dropout_p = 0.0 |
|
|
|
|
|
|
|
# |
|
|
|
# (deep breath) calculate attention and out projection |
|
|
|
# |
|
|
|
|
|
|
|
if need_weights: |
|
|
|
B, Nt, E = q.shape |
|
|
|
q_scaled = q / math.sqrt(E) |
|
|
|
|
|
|
|
assert not (is_causal and attn_mask is None |
|
|
|
), "FIXME: is_causal not implemented for need_weights" |
|
|
|
|
|
|
|
if attn_mask is not None: |
|
|
|
attn_output_weights = baddbmm(attn_mask, q_scaled, |
|
|
|
k.transpose(-2, -1)) |
|
|
|
else: |
|
|
|
attn_output_weights = jt.bmm(q_scaled, k.transpose(-2, -1)) |
|
|
|
attn_output_weights = softmax(attn_output_weights, dim=-1) |
|
|
|
if dropout_p > 0.0: |
|
|
|
attn_output_weights = dropout(attn_output_weights, p=dropout_p) |
|
|
|
|
|
|
|
attn_output = jt.bmm(attn_output_weights, v) |
|
|
|
|
|
|
|
attn_output = attn_output.transpose(0, 1).contiguous().view( |
|
|
|
tgt_len * bsz, embed_dim) |
|
|
|
attn_output = linear(attn_output, out_proj_weight, out_proj_bias) |
|
|
|
attn_output = attn_output.view(tgt_len, bsz, attn_output.size(1)) |
|
|
|
|
|
|
|
# optionally average attention weights over heads |
|
|
|
attn_output_weights = attn_output_weights.view(bsz, num_heads, tgt_len, |
|
|
|
src_len) |
|
|
|
if average_attn_weights: |
|
|
|
attn_output_weights = attn_output_weights.mean(dim=1) |
|
|
|
|
|
|
|
if not is_batched: |
|
|
|
# squeeze the output if input was unbatched |
|
|
|
attn_output = attn_output.squeeze(1) |
|
|
|
attn_output_weights = attn_output_weights.squeeze(0) |
|
|
|
return attn_output, attn_output_weights |
|
|
|
else: |
|
|
|
# attn_mask can be either (L,S) or (N*num_heads, L, S) |
|
|
|
# if attn_mask's shape is (1, L, S) we need to unsqueeze to (1, 1, L, S) |
|
|
|
# in order to match the input for SDPA of (N, num_heads, L, S) |
|
|
|
if attn_mask is not None: |
|
|
|
if attn_mask.size(0) == 1 and attn_mask.dim() == 3: |
|
|
|
attn_mask = attn_mask.unsqueeze(0) |
|
|
|
else: |
|
|
|
attn_mask = attn_mask.view(bsz, num_heads, -1, src_len) |
|
|
|
|
|
|
|
q = q.view(bsz, num_heads, tgt_len, head_dim) |
|
|
|
k = k.view(bsz, num_heads, src_len, head_dim) |
|
|
|
v = v.view(bsz, num_heads, src_len, head_dim) |
|
|
|
|
|
|
|
attn_output = scaled_dot_product_attention(q, |
|
|
|
k, |
|
|
|
v, |
|
|
|
attn_mask, |
|
|
|
dropout_p, |
|
|
|
is_causal, |
|
|
|
training=training) |
|
|
|
attn_output = attn_output.permute(2, 0, 1, 3).contiguous().view( |
|
|
|
bsz * tgt_len, embed_dim) |
|
|
|
|
|
|
|
attn_output = linear(attn_output, out_proj_weight, out_proj_bias) |
|
|
|
attn_output = attn_output.view(tgt_len, bsz, attn_output.size(1)) |
|
|
|
if not is_batched: |
|
|
|
# squeeze the output if input was unbatched |
|
|
|
attn_output = attn_output.squeeze(1) |
|
|
|
return attn_output, None |
|
|
|
|
|
|
|
|
|
|
|
class MultiheadAttention(Module): |
|
|
|
__constants__ = ['batch_first'] |
|
|
|
bias_k: Optional[jt.Var] |
|
|
|
bias_v: Optional[jt.Var] |
|
|
|
|
|
|
|
def __init__(self, |
|
|
|
embed_dim, |
|
|
|
num_heads, |
|
|
|
dropout=0., |
|
|
|
bias=True, |
|
|
|
add_bias_kv=False, |
|
|
|
add_zero_attn=False, |
|
|
|
kdim=None, |
|
|
|
vdim=None, |
|
|
|
batch_first=False, |
|
|
|
dtype=jt.float32) -> None: |
|
|
|
if embed_dim <= 0 or num_heads <= 0: |
|
|
|
raise ValueError( |
|
|
|
f"embed_dim and num_heads must be greater than 0," |
|
|
|
f" got embed_dim={embed_dim} and num_heads={num_heads} instead" |
|
|
|
) |
|
|
|
factory_kwargs = {'dtype': dtype} |
|
|
|
super().__init__() |
|
|
|
self.embed_dim = embed_dim |
|
|
|
self.kdim = kdim if kdim is not None else embed_dim |
|
|
|
self.vdim = vdim if vdim is not None else embed_dim |
|
|
|
self._qkv_same_embed_dim = self.kdim == embed_dim and self.vdim == embed_dim |
|
|
|
|
|
|
|
self.num_heads = num_heads |
|
|
|
self.dropout = dropout |
|
|
|
self.batch_first = batch_first |
|
|
|
self.head_dim = embed_dim // num_heads |
|
|
|
assert self.head_dim * num_heads == self.embed_dim, "embed_dim must be divisible by num_heads" |
|
|
|
|
|
|
|
if not self._qkv_same_embed_dim: |
|
|
|
self.q_proj_weight = jt.empty((embed_dim, embed_dim), |
|
|
|
**factory_kwargs) |
|
|
|
self.k_proj_weight = jt.empty((embed_dim, self.kdim), |
|
|
|
**factory_kwargs) |
|
|
|
self.v_proj_weight = jt.empty((embed_dim, self.vdim), |
|
|
|
**factory_kwargs) |
|
|
|
self.in_proj_weight = None |
|
|
|
else: |
|
|
|
self.q_proj_weight = None |
|
|
|
self.k_proj_weight = None |
|
|
|
self.v_proj_weight = None |
|
|
|
self.in_proj_weight = jt.empty((3 * embed_dim, embed_dim), |
|
|
|
**factory_kwargs) |
|
|
|
|
|
|
|
if bias: |
|
|
|
self.in_proj_bias = jt.empty(3 * embed_dim, **factory_kwargs) |
|
|
|
else: |
|
|
|
self.in_proj_bias = None |
|
|
|
self.out_proj = Linear(embed_dim, embed_dim, bias=bias) |
|
|
|
|
|
|
|
if add_bias_kv: |
|
|
|
self.bias_k = jt.empty((1, 1, embed_dim), **factory_kwargs) |
|
|
|
self.bias_v = jt.empty((1, 1, embed_dim), **factory_kwargs) |
|
|
|
else: |
|
|
|
self.bias_k = self.bias_v = None |
|
|
|
|
|
|
|
self.add_zero_attn = add_zero_attn |
|
|
|
|
|
|
|
self._reset_parameters() |
|
|
|
|
|
|
|
def _reset_parameters(self): |
|
|
|
if self._qkv_same_embed_dim: |
|
|
|
xavier_uniform_(self.in_proj_weight) |
|
|
|
else: |
|
|
|
xavier_uniform_(self.q_proj_weight) |
|
|
|
xavier_uniform_(self.k_proj_weight) |
|
|
|
xavier_uniform_(self.v_proj_weight) |
|
|
|
|
|
|
|
if self.in_proj_bias is not None: |
|
|
|
constant_(self.in_proj_bias, 0.) |
|
|
|
constant_(self.out_proj.bias, 0.) |
|
|
|
if self.bias_k is not None: |
|
|
|
xavier_gauss_(self.bias_k) |
|
|
|
if self.bias_v is not None: |
|
|
|
xavier_gauss_(self.bias_v) |
|
|
|
|
|
|
|
def __setstate__(self, state): |
|
|
|
# Support loading old MultiheadAttention checkpoints generated by v1.1.0 |
|
|
|
if '_qkv_same_embed_dim' not in state: |
|
|
|
state['_qkv_same_embed_dim'] = True |
|
|
|
|
|
|
|
super().__setstate__(state) |
|
|
|
|
|
|
|
def execute(self, |
|
|
|
query: Var, |
|
|
|
key: Var, |
|
|
|
value: Var, |
|
|
|
key_padding_mask: Optional[Var] = None, |
|
|
|
need_weights: bool = True, |
|
|
|
attn_mask: Optional[Var] = None, |
|
|
|
average_attn_weights: bool = True, |
|
|
|
is_causal: bool = False) -> Tuple[Var, Optional[Var]]: |
|
|
|
|
|
|
|
##### |
|
|
|
# Fast Path is not Supported. |
|
|
|
##### |
|
|
|
|
|
|
|
is_batched = query.dim() == 3 |
|
|
|
|
|
|
|
key_padding_mask = _canonical_mask( |
|
|
|
mask=key_padding_mask, |
|
|
|
mask_name="key_padding_mask", |
|
|
|
other_type=_none_or_dtype(attn_mask), |
|
|
|
other_name="attn_mask", |
|
|
|
target_type=query.dtype) |
|
|
|
|
|
|
|
attn_mask = _canonical_mask( |
|
|
|
mask=attn_mask, |
|
|
|
mask_name="attn_mask", |
|
|
|
other_type=None, |
|
|
|
other_name="", |
|
|
|
target_type=query.dtype, |
|
|
|
check_other=False, |
|
|
|
) |
|
|
|
|
|
|
|
if self.batch_first and is_batched: |
|
|
|
# make sure that the transpose op does not affect the "is" property |
|
|
|
if key is value: |
|
|
|
if query is key: |
|
|
|
query = key = value = query.transpose(1, 0) |
|
|
|
else: |
|
|
|
query, key = (x.transpose(1, 0) for x in (query, key)) |
|
|
|
value = key |
|
|
|
else: |
|
|
|
query, key, value = (x.transpose(1, 0) |
|
|
|
for x in (query, key, value)) |
|
|
|
|
|
|
|
if not self._qkv_same_embed_dim: |
|
|
|
attn_output, attn_output_weights = multi_head_attention_forward( |
|
|
|
query, |
|
|
|
key, |
|
|
|
value, |
|
|
|
self.embed_dim, |
|
|
|
self.num_heads, |
|
|
|
self.in_proj_weight, |
|
|
|
self.in_proj_bias, |
|
|
|
self.bias_k, |
|
|
|
self.bias_v, |
|
|
|
self.add_zero_attn, |
|
|
|
self.dropout, |
|
|
|
self.out_proj.weight, |
|
|
|
self.out_proj.bias, |
|
|
|
training=self.is_training(), |
|
|
|
key_padding_mask=key_padding_mask, |
|
|
|
need_weights=need_weights, |
|
|
|
attn_mask=attn_mask, |
|
|
|
use_separate_proj_weight=True, |
|
|
|
q_proj_weight=self.q_proj_weight, |
|
|
|
k_proj_weight=self.k_proj_weight, |
|
|
|
v_proj_weight=self.v_proj_weight, |
|
|
|
average_attn_weights=average_attn_weights, |
|
|
|
is_causal=is_causal) |
|
|
|
else: |
|
|
|
attn_output, attn_output_weights = multi_head_attention_forward( |
|
|
|
query, |
|
|
|
key, |
|
|
|
value, |
|
|
|
self.embed_dim, |
|
|
|
self.num_heads, |
|
|
|
self.in_proj_weight, |
|
|
|
self.in_proj_bias, |
|
|
|
self.bias_k, |
|
|
|
self.bias_v, |
|
|
|
self.add_zero_attn, |
|
|
|
self.dropout, |
|
|
|
self.out_proj.weight, |
|
|
|
self.out_proj.bias, |
|
|
|
training=self.is_training(), |
|
|
|
key_padding_mask=key_padding_mask, |
|
|
|
need_weights=need_weights, |
|
|
|
attn_mask=attn_mask, |
|
|
|
average_attn_weights=average_attn_weights, |
|
|
|
is_causal=is_causal) |
|
|
|
if self.batch_first and is_batched: |
|
|
|
return attn_output.transpose(1, 0), attn_output_weights |
|
|
|
else: |
|
|
|
return attn_output, attn_output_weights |