[layer] Performance optimizations to LSTMCell

Add minor performance optimizations to LSTMCell.

Signed-off-by: Parichay Kapoor <pk.kapoor@samsung.com>

diff --git a/nntrainer/layers/lstmcell.cpp b/nntrainer/layers/lstmcell.cpp
index 1acac65..0807061 100644 (file)
--- a/nntrainer/layers/lstmcell.cpp
+++ b/nntrainer/layers/lstmcell.cpp
@@ -211,13 +211,13 @@ void LSTMCellLayer::forwarding(RunLayerContext &context, bool training) {
   Tensor fgio_t = fgio.getBatchSlice(start_timestep, 1);
 
   input_.dot(weight_xh, fgio_t);
-  fgio_t.add_i(bias_h);
 
   if (start_timestep > 0) {
     Tensor hs_prev = hidden_.getBatchSlice(start_timestep - 1, 1);
     hs_prev.dot(weight_hh, fgio_t, false, false, 1.0);
   }
 
+  fgio_t.add_i(bias_h);
   Tensor hif = fgio_t.getSharedDataTensor({batch, unit * 2}, 0, false);
   Tensor hi = fgio_t.getSharedDataTensor({batch, unit}, 0, false);
   Tensor hf = fgio_t.getSharedDataTensor({batch, unit}, unit, false);
@@ -302,10 +302,6 @@ void LSTMCellLayer::calcGradient(RunLayerContext &context) {
     djdw_x.setZero();
     djdw_h.setZero();
     djdb_h.setZero();
-
-    dm_cell_.setZero();
-    derivative_.setZero();
-    d_fgio.setZero();
   }
 
   Tensor dh = derivative_.getBatchSlice(start_timestep, 1);
@@ -370,11 +366,12 @@ void LSTMCellLayer::calcGradient(RunLayerContext &context) {
   recurrent_acti_func.run_prime_fn(ho, dho, dho);
   recurrent_acti_func.run_prime_fn(hif, dhif, dhif);
   acti_func.run_prime_fn(hg, dhg, dhg);
-  djdb_h.add_i(dfgio_t.sum(2));
-  djdw_x.add_i(xs.dot(dfgio_t, true, false));
+  dfgio_t.sum(2, djdb_h, 1.0, 1.0);
+
+  xs.dot(dfgio_t, djdw_x, true, false, 1.0f);
   if (start_timestep != 0) {
     Tensor hs_prev = hidden_.getBatchSlice(start_timestep - 1, 1);
-    djdw_h.add_i(hs_prev.dot(dfgio_t, true, false));
+    hs_prev.dot(dfgio_t, djdw_h, true, false, 1.0f);
     Tensor dh_nx = derivative_.getBatchSlice(start_timestep - 1, 1);
     dfgio_t.dot(weight_hh, dh_nx, false, true, 1.0f);
   }