Backend separation

.gitignore

@@ -6,6 +6,8 @@ __pycache__
 *.mod
 *.a
 PROC*
+!madgraph/iolibs/template_files/madmatrix/ProcessData.h
+!madgraph/iolibs/template_files/madmatrix/ProcessTables.h
 cmd*
 ptest*
 *.pkl

madgraph/iolibs/template_files/madmatrix/ColorData.h

@@ -0,0 +1,44 @@
+// Copyright (C) 2020-2026 CERN and UCLouvain.
+// Licensed under the GNU Lesser General Public License (version 3 or later).
+// Integrated with the MadGraph7 project in Feb 2026.
+//
+// Process-specific color structure, generated once per subprocess: the
+// normalized color matrix (for color_sum_cpu/color_sum_gpu) and the
+// diagram/channel/config maps for multichannel color selection.
+
+#ifndef COLORDATA_H
+#define COLORDATA_H 1
+
+#include "mgOnGpuConfig.h"
+#include "ProcessData.h"
+
+namespace ColorMatrixData
+{
+  constexpr int ncolor = ProcessData::ncolor;
+
+%(color_matrix_lines)s
+}
+
+namespace mgOnGpu
+{
+  // Diagram: C-indexed [0,ndiagrams). Channel (channelId): F-indexed [1,nchannels],
+  // not all diagrams have one (#919); channelId-1 indexes channel2iconfig. Config
+  // (iconfig): F-indexed [1,nconfigSDE]; iconfig-1 indexes icolamp.
+  constexpr unsigned int nchannels = %(nb_diag)i; // may be < ndiagrams, see #919
+  static_assert( nchannels <= ProcessData::ndiagrams, "nchannels should be <= ndiagrams" ); // #910 #919
+
+  // Map channel (C-indexed) to iconfig (F-indexed); -1 = no associated iconfig (#917)
+  __device__ constexpr int channel2iconfig[%(nb_diag)i] = {
+%(channelc2iconfig_lines)s
+  };
+
+  // #configs with an associated iconfig for single-diagram enhancement (#917)
+  constexpr unsigned int nconfigSDE = %(nb_channel)s;
+
+  // Map iconfig (C-indexed) to the mask of allowed colors
+  __device__ constexpr bool icolamp[%(nb_channel)s][%(nb_color)s] = {
+%(is_LC)s
+  };
+}
+
+#endif // COLORDATA_H

madgraph/iolibs/template_files/madmatrix/MadgraphTest.h

@@ -27,11 +27,7 @@
 #include <string>
 #include <vector>
 
-#ifdef MGONGPUCPP_GPUIMPL
-using mg5amcGpu::CPPProcess;
-#else
-using mg5amcCpu::CPPProcess;
-#endif
+using madmatrix::CPPProcess;
 
 namespace
 {