use fused multiply-add pointwise ops in chroma (#8279)

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drhead 2025-05-30 18:09:54 -04:00 committed by GitHub
parent 6c319cbb4e
commit 08b7cc7506
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@ -80,15 +80,13 @@ class DoubleStreamBlock(nn.Module):
(img_mod1, img_mod2), (txt_mod1, txt_mod2) = vec
# prepare image for attention
img_modulated = self.img_norm1(img)
img_modulated = (1 + img_mod1.scale) * img_modulated + img_mod1.shift
img_modulated = torch.addcmul(img_mod1.shift, 1 + img_mod1.scale, self.img_norm1(img))
img_qkv = self.img_attn.qkv(img_modulated)
img_q, img_k, img_v = img_qkv.view(img_qkv.shape[0], img_qkv.shape[1], 3, self.num_heads, -1).permute(2, 0, 3, 1, 4)
img_q, img_k = self.img_attn.norm(img_q, img_k, img_v)
# prepare txt for attention
txt_modulated = self.txt_norm1(txt)
txt_modulated = (1 + txt_mod1.scale) * txt_modulated + txt_mod1.shift
txt_modulated = torch.addcmul(txt_mod1.shift, 1 + txt_mod1.scale, self.txt_norm1(txt))
txt_qkv = self.txt_attn.qkv(txt_modulated)
txt_q, txt_k, txt_v = txt_qkv.view(txt_qkv.shape[0], txt_qkv.shape[1], 3, self.num_heads, -1).permute(2, 0, 3, 1, 4)
txt_q, txt_k = self.txt_attn.norm(txt_q, txt_k, txt_v)
@ -102,12 +100,12 @@ class DoubleStreamBlock(nn.Module):
txt_attn, img_attn = attn[:, : txt.shape[1]], attn[:, txt.shape[1] :]
# calculate the img bloks
img = img + img_mod1.gate * self.img_attn.proj(img_attn)
img = img + img_mod2.gate * self.img_mlp((1 + img_mod2.scale) * self.img_norm2(img) + img_mod2.shift)
img.addcmul_(img_mod1.gate, self.img_attn.proj(img_attn))
img.addcmul_(img_mod2.gate, self.img_mlp(torch.addcmul(img_mod2.shift, 1 + img_mod2.scale, self.img_norm2(img))))
# calculate the txt bloks
txt += txt_mod1.gate * self.txt_attn.proj(txt_attn)
txt += txt_mod2.gate * self.txt_mlp((1 + txt_mod2.scale) * self.txt_norm2(txt) + txt_mod2.shift)
txt.addcmul_(txt_mod1.gate, self.txt_attn.proj(txt_attn))
txt.addcmul_(txt_mod2.gate, self.txt_mlp(torch.addcmul(txt_mod2.shift, 1 + txt_mod2.scale, self.txt_norm2(txt))))
if txt.dtype == torch.float16:
txt = torch.nan_to_num(txt, nan=0.0, posinf=65504, neginf=-65504)
@ -152,7 +150,7 @@ class SingleStreamBlock(nn.Module):
def forward(self, x: Tensor, pe: Tensor, vec: Tensor, attn_mask=None) -> Tensor:
mod = vec
x_mod = (1 + mod.scale) * self.pre_norm(x) + mod.shift
x_mod = torch.addcmul(mod.shift, 1 + mod.scale, self.pre_norm(x))
qkv, mlp = torch.split(self.linear1(x_mod), [3 * self.hidden_size, self.mlp_hidden_dim], dim=-1)
q, k, v = qkv.view(qkv.shape[0], qkv.shape[1], 3, self.num_heads, -1).permute(2, 0, 3, 1, 4)
@ -162,7 +160,7 @@ class SingleStreamBlock(nn.Module):
attn = attention(q, k, v, pe=pe, mask=attn_mask)
# compute activation in mlp stream, cat again and run second linear layer
output = self.linear2(torch.cat((attn, self.mlp_act(mlp)), 2))
x += mod.gate * output
x.addcmul_(mod.gate, output)
if x.dtype == torch.float16:
x = torch.nan_to_num(x, nan=0.0, posinf=65504, neginf=-65504)
return x
@ -178,6 +176,6 @@ class LastLayer(nn.Module):
shift, scale = vec
shift = shift.squeeze(1)
scale = scale.squeeze(1)
x = (1 + scale[:, None, :]) * self.norm_final(x) + shift[:, None, :]
x = torch.addcmul(shift[:, None, :], 1 + scale[:, None, :], self.norm_final(x))
x = self.linear(x)
return x