Add awq dequantize kernel to sgl with 1x to 3x speedup (#4104)

sgl-kernel/python/sgl_kernel/__init__.py

@@ -23,6 +23,7 @@ from sgl_kernel.elementwise import (
     silu_and_mul,
 )
 from sgl_kernel.gemm import (
+    awq_dequantize,
     bmm_fp8,
     cublas_grouped_gemm,
     fp8_blockwise_scaled_mm,

sgl-kernel/python/sgl_kernel/gemm.py

@@ -4,6 +4,12 @@ import torch
 from sgl_kernel.utils import _get_cache_buf, get_cuda_stream
 
 
+def awq_dequantize(
+    qweight: torch.Tensor, scales: torch.Tensor, qzeros: torch.Tensor
+) -> torch.ByteTensor:
+    return torch.ops.sgl_kernels.awq_dequantize(qweight, scales, qzeros)
+
+
 def int8_scaled_mm(mat_a, mat_b, scales_a, scales_b, out_dtype, bias=None):
     return torch.ops.sgl_kernel.int8_scaled_mm(
         mat_a,