fix cogview4 rotary pos embed

Author: chengzeyi

src/diffusers/models/transformers/transformer_cogview4.py

@@ -244,28 +244,30 @@ class CogView4RotaryPosEmbed(nn.Module):
     def __init__(self, dim: int, patch_size: int, rope_axes_dim: Tuple[int, int], theta: float = 10000.0) -> None:
         super().__init__()
 
+        self.dim = dim
         self.patch_size = patch_size
         self.rope_axes_dim = rope_axes_dim
-
-        dim_h, dim_w = dim // 2, dim // 2
-        h_inv_freq = 1.0 / (theta ** (torch.arange(0, dim_h, 2, dtype=torch.float32)[: (dim_h // 2)].float() / dim_h))
-        w_inv_freq = 1.0 / (theta ** (torch.arange(0, dim_w, 2, dtype=torch.float32)[: (dim_w // 2)].float() / dim_w))
-        h_seq = torch.arange(self.rope_axes_dim[0])
-        w_seq = torch.arange(self.rope_axes_dim[1])
-        self.freqs_h = self.register_buffer("freqs_h", torch.outer(h_seq, h_inv_freq), persistent=False)
-        self.freqs_w = self.register_buffer("freqs_h", torch.outer(w_seq, w_inv_freq), persistent=False)
+        self.theta = theta
 
     def forward(self, hidden_states: torch.Tensor) -> Tuple[torch.Tensor, torch.Tensor]:
         batch_size, num_channels, height, width = hidden_states.shape
         height, width = height // self.patch_size, width // self.patch_size
 
-        h_idx = torch.arange(height, device=self.freqs_h.device)
-        w_idx = torch.arange(width, device=self.freqs_w.device)
+        dim_h, dim_w = self.dim // 2, self.dim // 2
+        h_inv_freq = 1.0 / (self.theta ** (torch.arange(0, dim_h, 2, dtype=torch.float32)[: (dim_h // 2)].float() / dim_h))
+        w_inv_freq = 1.0 / (self.theta ** (torch.arange(0, dim_w, 2, dtype=torch.float32)[: (dim_w // 2)].float() / dim_w))
+        h_seq = torch.arange(self.rope_axes_dim[0])
+        w_seq = torch.arange(self.rope_axes_dim[1])
+        freqs_h = torch.outer(h_seq, h_inv_freq)
+        freqs_w = torch.outer(w_seq, w_inv_freq)
+
+        h_idx = torch.arange(height, device=freqs_h.device)
+        w_idx = torch.arange(width, device=freqs_w.device)
         inner_h_idx = h_idx * self.rope_axes_dim[0] // height
         inner_w_idx = w_idx * self.rope_axes_dim[1] // width
 
-        freqs_h = self.freqs_h[inner_h_idx]
-        freqs_w = self.freqs_w[inner_w_idx]
+        freqs_h = freqs_h[inner_h_idx]
+        freqs_w = freqs_w[inner_w_idx]
 
         # Create position matrices for height and width
         # [height, 1, dim//4] and [1, width, dim//4]