add support for beam search (tested with beam size 2)

source/sample/transformer/T2TPredictor.cpp

@@ -101,25 +101,10 @@ void T2TPredictor::Create(T2TModel* model, XTensor* top, const XTensor* input, i
     InitTensorV2(&state->nstep, input->order, dims, X_FLOAT, 1.0F, input->devID);
     InitTensorV2(&state->endMark, input->order, dims, X_INT, 1.0F, input->devID);
 
-    /*float* data = new float[state->probPath.unitNum];
-    for (int i = 0; i < state->probPath.unitNum; ++i) {
-        data[i] = -1e20F;
-        if (i % beamSize == 0)
-            data[i] = 0;
-    }
-    state->probPath.SetData(data, state->probPath.unitNum);
-    delete[] data;*/
-
-    SetDataFixed(state->probPath, -1e9F);
-    for (int i = 0; i < state->probPath.unitNum; ++i) {
-        if (i % beamSize == 0)
-            state->probPath.Set(0.0F, i);
-    }
-    
+    state->probPath.SetZeroAll();
     state->nstep.SetZeroAll();
     state->endMark.SetZeroAll();
 
-    
     state->stateNum = 0;
 }
 

source/sample/transformer/T2TSearch.cpp

@@ -285,11 +285,11 @@ void T2TSearch::Generate(T2TStateBundle* beam)
     XTensor mask;
     InitTensorV2(&mask, 1, dimMask, X_FLOAT, 1.0F, -1);
     mask.SetZeroAll();
-    mask.Set1D(-1e20F, 0);
-    mask.Set1D(-1e20F, 1);
+    mask.Set1D(-1e9F, 0);
+    mask.Set1D(-1e9F, 1);
     mask.SetDevice(score.devID, score.mem);
 
-    //_SumDim(&score, &mask, 2);
+    _SumDim(&score, &mask, 2);
     score.Reshape(order, dimsBeam);
 
     /* keep the most promissing candidates in the beam */
@@ -324,9 +324,6 @@ void T2TSearch::Generate(T2TStateBundle* beam)
         for (int j = 0; j < beamSize; j++)
             indexGPU.SetInt(i * stride + indexGPU.GetInt(i + j), i + j);
     }
-    /*for (int i = 0; i < indexGPU.unitNum; i++) {
-        indexGPU.SetInt(i + indexGPU.GetInt(i), i);
-    }*/
 
     CheckNTErrors(IsSameShaped(prob, probPath), "Wrong tensor shape!");