ggml : get_rows : support non-contiguos tensors with gaps, generalize up to 3D

Author: slaren

Diff for: ggml.c

@@ -4734,7 +4734,8 @@ struct ggml_tensor * ggml_get_rows(
         struct ggml_tensor  * a,
         struct ggml_tensor  * b) {
     GGML_ASSERT(a->ne[2] == b->ne[1]);
-    GGML_ASSERT(ggml_is_matrix(b) && b->type == GGML_TYPE_I32);
+    GGML_ASSERT(b->ne[3] == 1);
+    GGML_ASSERT(b->type == GGML_TYPE_I32);
 
     bool is_node = false;
 
@@ -4744,7 +4745,7 @@ struct ggml_tensor * ggml_get_rows(
 
     // TODO: implement non F32 return
     //struct ggml_tensor * result = ggml_new_tensor_2d(ctx, a->type, a->ne[0], b->ne[0]);
-    struct ggml_tensor * result = ggml_new_tensor_3d(ctx, GGML_TYPE_F32, a->ne[0], b->ne[0], b->ne[1]);
+    struct ggml_tensor * result = ggml_new_tensor_4d(ctx, GGML_TYPE_F32, a->ne[0], b->ne[0], b->ne[1], b->ne[2]);
 
     result->op   = GGML_OP_GET_ROWS;
     result->grad = is_node ? ggml_dup_tensor(ctx, result) : NULL;
@@ -10414,22 +10415,24 @@ static void ggml_compute_forward_get_rows_f32(
     GGML_TENSOR_BINARY_OP_LOCALS
 
     const int64_t nc = ne00;
-    const int64_t nr = ggml_nelements(src1);
 
     assert(ne0  == nc);
     assert(ne02 == ne11);
     assert(nb00 == sizeof(float));
     assert(ggml_nrows(dst) == nr);
 
     // TODO: multi-thread
-    for (int64_t i = 0; i < nr; ++i) {
-        const int64_t r = ((int32_t *) src1->data)[i];
-
-        const int64_t i02 = i/ne10;
-
-        ggml_vec_cpy_f32(nc,
-                (float *) ((char *)  dst->data + i*nb1),
-                (float *) ((char *) src0->data + i02*nb02 + r*nb01));
+    // TODO: same impl for get_rows_q and get_rows_f16
+    for (int64_t i12 = 0; i12 < ne12; ++i12) {
+        for (int64_t i11 = 0; i11 < ne11; ++i11) {
+            for (int64_t i10 = 0; i10 < ne10; ++i10) {
+                const int64_t i01 = *(int32_t *) ((char *) src1->data + i10*nb10 + i11*nb11 + i12*nb12);
+
+                ggml_vec_cpy_f32(nc,
+                        (float *) ((char *)  dst->data + i10*nb1  + i11*nb2  + i12*nb3),
+                        (float *) ((char *) src0->data + i01*nb01 + i11*nb02 + i12*nb03));
+            }
+        }
     }
 }