From 665094d94b249ecf065f2219bd0eb3ee3637723d Mon Sep 17 00:00:00 2001
From: Peter Boyle <paboyle@ph.ed.ac.uk>
Date: Wed, 19 Aug 2026 19:38:48 -0400
Subject: [PATCH] Lex gauge actions.

---
 Grid/qcd/action/gauge/GaugeImplTypes.h       | 27 ++++++++++++++++----
 Grid/qcd/action/gauge/GaugeImplementations.h | 18 +++++++++++++
 2 files changed, 40 insertions(+), 5 deletions(-)

diff --git a/Grid/qcd/action/gauge/GaugeImplTypes.h b/Grid/qcd/action/gauge/GaugeImplTypes.h
index 95b692905..9ee0553b5 100644
--- a/Grid/qcd/action/gauge/GaugeImplTypes.h
+++ b/Grid/qcd/action/gauge/GaugeImplTypes.h
@@ -60,8 +60,10 @@ NAMESPACE_BEGIN(Grid);
   typedef typename Impl::SiteField SiteField;	    \
   typedef typename Impl::Field Field;
 
-// hardcodes the exponential approximation in the template
-template <class S, int Nrepresentation = Nc, int Nexp = 12, class Group = SU<Nc> > class GaugeImplTypes {
+// Order of the exponential approximation
+const int NexpDefault = 12;
+
+template <class S, int Nrepresentation = Nc, int Nexp = NexpDefault, class Group = SU<Nc> > class GaugeImplTypes {
 public:
   typedef S Simd;
   typedef typename Simd::scalar_type scalar_type;
@@ -188,14 +190,29 @@ typedef GaugeImplTypes<vComplex, Nc> GimplTypesR;
 typedef GaugeImplTypes<vComplexF, Nc> GimplTypesF;
 typedef GaugeImplTypes<vComplexD, Nc> GimplTypesD;
 
-typedef GaugeImplTypes<vComplex, Nc, 12, Sp<Nc> > SpGimplTypesR;
-typedef GaugeImplTypes<vComplexF, Nc, 12, Sp<Nc> > SpGimplTypesF;
-typedef GaugeImplTypes<vComplexD, Nc, 12, Sp<Nc> > SpGimplTypesD;
+typedef GaugeImplTypes<vComplex, Nc, NexpDefault, Sp<Nc> > SpGimplTypesR;
+typedef GaugeImplTypes<vComplexF, Nc, NexpDefault, Sp<Nc> > SpGimplTypesF;
+typedef GaugeImplTypes<vComplexD, Nc, NexpDefault, Sp<Nc> > SpGimplTypesD;
 
 typedef GaugeImplTypes<vComplex, SU<Nc>::AdjointDimension> GimplAdjointTypesR;
 typedef GaugeImplTypes<vComplexF, SU<Nc>::AdjointDimension> GimplAdjointTypesF;
 typedef GaugeImplTypes<vComplexD, SU<Nc>::AdjointDimension> GimplAdjointTypesD;
 
+/////////////////////////////////////////////////////////////////////////////
+// Lexicographic gauge implementation types
+/////////////////////////////////////////////////////////////////////////////
+typedef GaugeImplTypes<sComplexF, Nc> lexGimplTypesF;
+typedef GaugeImplTypes<sComplexD, Nc> lexGimplTypesD;
+
+typedef GaugeImplTypes<sComplexF, Nc, NexpDefault, Sp<Nc> > lexSpGimplTypesF;
+typedef GaugeImplTypes<sComplexD, Nc, NexpDefault, Sp<Nc> > lexSpGimplTypesD;
+
+typedef GaugeImplTypes<sComplexF, SU<Nc>::AdjointDimension> lexGimplAdjointTypesF;
+typedef GaugeImplTypes<sComplexD, SU<Nc>::AdjointDimension> lexGimplAdjointTypesD;
+/////////////////////////////////////////////////////////////////////////////
+// End lexicographic gauge implementation types
+/////////////////////////////////////////////////////////////////////////////
+
 
 
 
diff --git a/Grid/qcd/action/gauge/GaugeImplementations.h b/Grid/qcd/action/gauge/GaugeImplementations.h
index 62141c83f..47abbaf98 100644
--- a/Grid/qcd/action/gauge/GaugeImplementations.h
+++ b/Grid/qcd/action/gauge/GaugeImplementations.h
@@ -197,6 +197,24 @@ typedef PeriodicGaugeImpl<SpGimplTypesR> SpPeriodicGimplR; // Real.. whichever p
 typedef PeriodicGaugeImpl<SpGimplTypesF> SpPeriodicGimplF; // Float
 typedef PeriodicGaugeImpl<SpGimplTypesD> SpPeriodicGimplD; // Double
 
+/////////////////////////////////////////////////////////////////////////////
+// Lexicographic gauge implementations
+/////////////////////////////////////////////////////////////////////////////
+typedef PeriodicGaugeImpl<lexGimplTypesF> lexPeriodicGimplF;
+typedef PeriodicGaugeImpl<lexGimplTypesD> lexPeriodicGimplD;
+
+typedef PeriodicGaugeImpl<lexGimplAdjointTypesF> lexPeriodicGimplAdjF;
+typedef PeriodicGaugeImpl<lexGimplAdjointTypesD> lexPeriodicGimplAdjD;
+
+typedef ConjugateGaugeImpl<lexGimplTypesF> lexConjugateGimplF;
+typedef ConjugateGaugeImpl<lexGimplTypesD> lexConjugateGimplD;
+
+typedef PeriodicGaugeImpl<lexSpGimplTypesF> lexSpPeriodicGimplF;
+typedef PeriodicGaugeImpl<lexSpGimplTypesD> lexSpPeriodicGimplD;
+/////////////////////////////////////////////////////////////////////////////
+// End lexicographic gauge implementations
+/////////////////////////////////////////////////////////////////////////////
+
 
 NAMESPACE_END(Grid);