transformer: add start of log reduction

sw/apps/transformer/src/transformer.h

@@ -925,21 +925,30 @@ static inline void transformer_layer_fp64(transformer_layer_fp64_t *const l) {
 
                     snrt_cluster_hw_barrier();
 
-                    for (int i = 0; i < B_r_lin2 / num_cores; i++) {
-                        for (int j = 0; j < B_c_lin2; j++) {
-                            dump_idx(i * B_c_lin2 + j + ofmap_offset);
-                            dump_debug(ofmap_lin2[i * B_c_lin2 + j + ofmap_offset]);
-                        }
-                    }
+                    // for (int i = 0; i < B_r_lin2 / num_cores; i++) {
+                    //     for (int j = 0; j < B_c_lin2; j++) {
+                    //         dump_idx(i * B_c_lin2 + j + ofmap_offset);
+                    //         dump_debug(ofmap_lin2[i * B_c_lin2 + j + ofmap_offset]);
+                    //     }
+                    // }
                 } else {
                     snrt_cluster_hw_barrier();
                 }
             }
             uint32_t end_loop_inner = snrt_mcycle();
         }
         uint32_t end_loop_outer = snrt_mcycle();
-
         snrt_cluster_hw_barrier();
+
+        // now we will add the partial results together
+        // in a logarithmic reduction fashion
+
+        float reduction_depth = log2(num_heads);
+        dump_debug(reduction_depth);
+        // round to the next integer (ceiling)
+        uint32_t reduction_depth_int = (uint32_t)ceil(reduction_depth);
+        dump_id(reduction_depth_int);
+
     }