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fix: remove causal cross attn mask

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This commit is contained in:
Zach Nussbaum 2023-04-21 14:23:33 +00:00
parent e62baf87f8
commit ca66d12d89
1 changed files with 0 additions and 25 deletions
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25
gpt4all/models/modeling_gpt_jr.py
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@ -316,34 +316,11 @@ class GPTJRCrossAttention(GPTJRAttention):
head_mask=None,
):
# compute causal mask from causal mask buffer
# since key and value don't have seq length, just use causal mask as normal
query_length = query.size(-2)
causal_mask = self.bias[:, :, : query_length, :query_length].to(torch.bool)
# Keep the attention weights computation in fp32 to avoid overflow issues
# TODO: do we need to do this with bfloat16??
# query = query.to(torch.float32)
# key = key.to(torch.float32)
# query -> (bs, seq_len, num_attention_heads, head_dim)
# key -> (bs, num_attention_heads, head_dim)
# attn_weights -> (bs, seq_len, num_attention_heads, num_attention_heads)
attn_weights = torch.matmul(query, key.transpose(-1, -2))
mask_value = torch.finfo(attn_weights.dtype).min
# Need to be a tensor, otherwise we get error: `RuntimeError: expected scalar type float but found double`.
# Need to be on the same device, otherwise `RuntimeError: ..., x and y to be on the same device`
mask_value = torch.tensor(mask_value, dtype=attn_weights.dtype).to(attn_weights.device)
attn_weights = torch.where(causal_mask, attn_weights, mask_value)
attn_weights = attn_weights / self.scale_attn
if attention_mask is not None:
# Apply the attention mask
# attn mask (1, 1, 1, seq_len)
attn_weights = (attn_weights.permute(0, 2, 3, 1) + attention_mask).permute(0, 3, 1, 2)
attn_weights = nn.functional.softmax(attn_weights, dim=-1)
attn_weights = attn_weights.to(value.dtype)
attn_weights = self.attn_dropout(attn_weights)
@ -441,8 +418,6 @@ class GPTJRBlock(nn.Module):
self.attn = GPTJRAttention(config)
self.mlp = GPTJRMLP(inner_dim, config)
# TODO: fix for n neighbors
# for SBERT this is 384
self.ln_2 = nn.LayerNorm(config.encoder_dim, eps=config.layer_norm_epsilon)
self.cross_attn = GPTJRCrossAttention(config)
self.cross_attn_mlp = GPTJRMLP(inner_dim, config)