2 files changed, 31 insertions, 0 deletions
diff --git a/matrix/generic/cukernel.cu b/matrix/generic/cukernel.cu
index 4b6af61..2e794b7 100644
--- a/matrix/generic/cukernel.cu
+++ b/matrix/generic/cukernel.cu
@@ -105,6 +105,15 @@ __global__ void cudak_(block_reduce_rowmax)(const MATRIX_ELEM *input,
         output[blockIdx.x + ostride * blockIdx.y] = cudak_(arr)[0];
 }
 
+__global__ void cudak_(add_row)(const MATRIX_ELEM *a, MATRIX_ELEM *b,
+                                int nrow, int ncol, int stride, double beta) {
+    int j = blockIdx.x * blockDim.x + threadIdx.x;
+    int i = blockIdx.y * blockDim.y + threadIdx.y;
+    if (i >= nrow || j >= ncol) return;
+    b[j + i * stride] += beta * a[j];
+}
+
+
 extern "C" {
 #include "../cukernel.h"
     void cudak_(cuda_sigmoid)(const Matrix *a, Matrix *b) {
@@ -222,5 +231,16 @@ extern "C" {
              ncol);
         cudaFree(res);
     }
+
+    /* in-place calc */
+    void cudak_(cuda_add_row)(const Matrix *a, Matrix *b, double beta) {
+        dim3 threadsPerBlock(CUDA_THREADS_N,
+                CUDA_THREADS_N);
+        dim3 numBlocks(CEIL_DIV(b->ncol, threadsPerBlock.x),
+                CEIL_DIV(b->nrow, threadsPerBlock.y));
+        cudak_(add_row)<<<numBlocks, threadsPerBlock>>> \
+            (MATRIX_ELEM_PTR(a), MATRIX_ELEM_PTR(b), b->nrow, b->ncol,
+            b->stride / sizeof(MATRIX_ELEM), beta);
+    }
 }
 #endif
diff --git a/matrix/generic/cumatrix.c b/matrix/generic/cumatrix.c
index 557e4c1..ae57b21 100644
--- a/matrix/generic/cumatrix.c
+++ b/matrix/generic/cumatrix.c
@@ -126,6 +126,15 @@ static int nerv_matrix_(rowmax)(lua_State *L) {
     return 1;
 }
 
+
+static int nerv_matrix_(add_row)(lua_State *L) {
+    Matrix *a = luaT_checkudata(L, 2, nerv_matrix_(tname));
+    Matrix *b = luaT_checkudata(L, 1, nerv_matrix_(tname));
+    double beta = luaL_checknumber(L, 3);
+    cudak_(cuda_add_row)(a, b, beta);
+    return 0;
+}
+
 extern const char *MATRIX_CUMATRIX_HOST_TNAME;
 static int nerv_matrix_(copy_from)(lua_State *L) {
     Matrix *a = luaT_checkudata(L, 1, nerv_matrix_(tname));
@@ -163,6 +172,8 @@ static const luaL_Reg nerv_matrix_(extra_methods)[] = {
     {"rowmax", nerv_matrix_(rowmax)},
     {"copy_from", nerv_matrix_(copy_from)},
     {"copy_to", nerv_matrix_(copy_to)},
+    /* in-place calc */
+    {"add_row", nerv_matrix_(add_row)},
     {NULL, NULL}
 };