1 files changed, 109 insertions, 0 deletions
diff --git a/gr-blocks/lib/sub_impl.cc b/gr-blocks/lib/sub_impl.cc
new file mode 100644
index 0000000000..ee4df1ed66
--- /dev/null
+++ b/gr-blocks/lib/sub_impl.cc
@@ -0,0 +1,109 @@
+/* -*- c++ -*- */
+/*
+ * Copyright 2004,2009,2010,2012,2018 Free Software Foundation, Inc.
+ *
+ * This file is part of GNU Radio
+ *
+ * GNU Radio is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 3, or (at your option)
+ * any later version.
+ *
+ * GNU Radio is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with GNU Radio; see the file COPYING.  If not, write to
+ * the Free Software Foundation, Inc., 51 Franklin Street,
+ * Boston, MA 02110-1301, USA.
+ */
+
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include "sub_impl.h"
+#include <gnuradio/io_signature.h>
+#include <volk/volk.h>
+
+namespace gr {
+  namespace blocks {
+
+    template <class T>
+    typename sub<T>::sptr sub<T>::make(size_t vlen)
+    {
+      return gnuradio::get_initial_sptr(new sub_impl<T> (vlen));
+    }
+
+    template <>
+    sub_impl<float>::sub_impl(size_t vlen)
+      : sync_block("@sub_ff",
+                   io_signature::make(1, -1, sizeof(float)*vlen),
+                   io_signature::make(1,  1, sizeof(float)*vlen)),
+      d_vlen(vlen)
+    {
+      const int alignment_multiple =
+	volk_get_alignment() / sizeof(float);
+      set_alignment(std::max(1, alignment_multiple));
+    }
+
+    template <>
+    int
+    sub_impl<float>::work(int noutput_items,
+		      gr_vector_const_void_star &input_items,
+		      gr_vector_void_star &output_items)
+    {
+      float *out = (float*)output_items[0];
+
+      int ninputs = input_items.size();
+      int noi = noutput_items*d_vlen;
+
+      const float *in = (const float*)input_items[0];
+      memcpy(out, in, noi*sizeof(float));
+      for(int i = 1; i < ninputs; i++) {
+        in = (const float*)input_items[i];
+        volk_32f_x2_subtract_32f(out, out, in, noi);
+      }
+
+      return noutput_items;
+    }
+
+    template <class T>
+    sub_impl<T> ::sub_impl(size_t vlen)
+      : sync_block ("sub",
+		       io_signature::make (1, -1, sizeof (T)*vlen),
+		       io_signature::make (1,  1, sizeof (T)*vlen)),
+      d_vlen(vlen)
+    {
+    }
+
+    template <class T>
+    int
+    sub_impl<T> ::work(int noutput_items,
+		      gr_vector_const_void_star &input_items,
+		      gr_vector_void_star &output_items)
+    {
+      T *optr = (T *) output_items[0];
+
+      int ninputs = input_items.size ();
+
+      for (size_t i = 0; i < noutput_items*d_vlen; i++){
+	T acc = ((T *) input_items[0])[i];
+	for (int j = 1; j < ninputs; j++)
+	  acc -= ((T *) input_items[j])[i];
+
+	*optr++ = (T) acc;
+      }
+
+      return noutput_items;
+    }
+
+template class sub<std::int16_t>;
+template class sub<std::int32_t>;
+template class sub<gr_complex>;
+template class sub<float>;
+  } /* namespace blocks */
+} /* namespace gr */