[refactor] update variable declaration for clarity in gemm_layouts and gemm_sp

Author: LeiWang1999

src/layout/gemm_layouts.cc

@@ -672,7 +672,7 @@ Layout makeTensorOpMultiplicand(int mat_stride, int mat_continuous,
           kElementsPerAccess +
       FloorMod(j, kElementsPerAccess);
 
-  PrimExpr element_strided = vec_strided_idx;
+  const PrimExpr &element_strided = vec_strided_idx;
 
   const int stride = mat_continuous;
 

src/op/gemm_sp.cc

@@ -40,14 +40,12 @@ std::pair<int, int> GemmSPWarpPolicyNode::ComputeWarpPartition(int M, int N,
     int warp_shape_n = N / n_warp;
     if (warp_shape_m % m_atom_size) { // GemmWarpPolicy::kFullRow
       m_warp = M / m_atom_size;
-      warp_shape_m = m_atom_size;
       ICHECK(m_warp > 0) << err_msg;
       n_warp = num_warps / m_warp;
       warp_shape_n = N / n_warp;
       ICHECK(warp_shape_n % n_atom_size == 0) << err_msg;
     } else if (warp_shape_n % n_atom_size != 0) { // GemmWarpPolicy::kFullColumn
       n_warp = N / n_atom_size;
-      warp_shape_n = n_atom_size;
       ICHECK(n_warp > 0) << err_msg;
       m_warp = num_warps / n_warp;
       warp_shape_m = M / m_warp;