diff --git a/include/flashinfer/sampling.cuh b/include/flashinfer/sampling.cuh
index 1a2aebd1..49329fbd 100644
--- a/include/flashinfer/sampling.cuh
+++ b/include/flashinfer/sampling.cuh
@@ -115,7 +115,7 @@ __device__ __forceinline__ void DeviceSamplingFromProb(
     bool greater_than_u_diff[VEC_SIZE];
 #ifdef FLASHINFER_CUB_SUBTRACTLEFT_DEFINED
     BlockAdjacentDifference<bool, BLOCK_THREADS>(temp_storage->block_prim.adj_diff)
-        .SubtractLeft<VEC_SIZE>(greater_than_u_diff, greater_than_u, BoolDiffOp());
+        .SubtractLeft<VEC_SIZE>(greater_than_u, greater_than_u_diff, BoolDiffOp());
 #else
     BlockAdjacentDifference<bool, BLOCK_THREADS>(temp_storage->block_prim.adj_diff)
         .FlagHeads<VEC_SIZE>(greater_than_u_diff, greater_than_u, BoolDiffOp());