[NFC] polish colossalai/kernel/cuda_native/csrc/kernels/include/block_reduce.h code style (#938)

colossalai/kernel/cuda_native/csrc/kernels/include/block_reduce.h

@@ -13,22 +13,23 @@ const float REDUCE_FLOAT_INF_NEG = -100000000.f;
 const float REDUCE_FLOAT_INF_POS = 100000000.f;
 const unsigned int WARP_REDUCE_SIZE = 32;
 
-template <typename T> __forceinline__ __device__ T warpReduceSum(T val) {
+template <typename T>
+__forceinline__ __device__ T warpReduceSum(T val) {
   for (int mask = (WARP_REDUCE_SIZE >> 1); mask > 0; mask >>= 1)
     val += __shfl_xor_sync(WARP_REDUCE_MASK, val, mask, WARP_REDUCE_SIZE);
   return val;
 }
 
 /* Calculate the sum of all elements in a block */
-template <typename T> __forceinline__ __device__ T blockReduceSum(T val) {
+template <typename T>
+__forceinline__ __device__ T blockReduceSum(T val) {
   static __shared__ T shared[32];
   int lane = threadIdx.x & 0x1f;
   int wid = threadIdx.x >> 5;
 
   val = warpReduceSum<T>(val);
 
-  if (lane == 0)
+  if (lane == 0) shared[wid] = val;
-    shared[wid] = val;
   __syncthreads();
 
   val = (threadIdx.x < (blockDim.x >> 5)) ? shared[lane] : (T)0.0f;