Minor speed up block_quant_dequant (#6814)

This commit is contained in:
fzyzcjy
2025-06-14 05:32:46 +08:00
committed by GitHub
parent b04df75acd
commit e3ec6bf4b6

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@@ -369,27 +369,15 @@ def block_quant_dequant(
The output is an unquantized tensor with dtype.
"""
block_n, block_k = block_size[0], block_size[1]
n, k = x_q_block.shape
n_tiles = (n + block_n - 1) // block_n
k_tiles = (k + block_k - 1) // block_k
assert n_tiles == x_s.shape[0]
assert k_tiles == x_s.shape[1]
*_, n, k = x_q_block.shape
x_dq_block = torch.empty_like(x_q_block, dtype=dtype)
# ... n_scale k_scale -> ... (n_scale block_n) (k_scale block_k)
x_scale_repeat = x_s.repeat_interleave(block_n, dim=-2).repeat_interleave(
block_k, dim=-1
)
x_scale_repeat = x_scale_repeat[..., :n, :k]
for j in range(n_tiles):
for i in range(k_tiles):
x_q_block_tile = x_q_block[
j * block_n : min((j + 1) * block_n, n),
i * block_k : min((i + 1) * block_k, k),
]
x_dq_block_tile = x_dq_block[
j * block_n : min((j + 1) * block_n, n),
i * block_k : min((i + 1) * block_k, k),
]
x_dq_block_tile[:, :] = x_q_block_tile.to(torch.float32) * x_s[j][i]
return x_dq_block
return (x_q_block.to(torch.float32) * x_scale_repeat).to(dtype)
def channel_quant_to_tensor_quant(