From e36b9bc6fdb888baeeca43617de15efa000e4cac Mon Sep 17 00:00:00 2001
From: Christian Zimmermann <christian.zimmermann@ur.de>
Date: Tue, 15 Oct 2024 10:51:23 -0700
Subject: [PATCH] mpi: WIP: add rank acc xpr

---
 src/opt/mpi/include/racc_xpr.cc.h | 46 +++++++++++++++++++++++++++++++
 src/opt/mpi/include/racc_xpr.h    | 45 ++++++++++++++++++++++++++++++
 2 files changed, 91 insertions(+)
 create mode 100644 src/opt/mpi/include/racc_xpr.cc.h
 create mode 100644 src/opt/mpi/include/racc_xpr.h

diff --git a/src/opt/mpi/include/racc_xpr.cc.h b/src/opt/mpi/include/racc_xpr.cc.h
new file mode 100644
index 0000000..5ed1b31
--- /dev/null
+++ b/src/opt/mpi/include/racc_xpr.cc.h
@@ -0,0 +1,46 @@
+
+#ifndef __cxz_mpi_racc_xpr_cc_h__
+#define __cxz_mpi_racc_xpr_cc_h__
+
+#include "racc_xpr.h"
+
+namespace CNOXRZ
+{
+    namespace mpi
+    {
+	template <SizeT L, class Xpr, class F = NoF>
+	constexpr RankAccXpr<L,Xpr,F>::RankAccXpr(SizeT size, const IndexId<L>& id,
+						  const Xpr& xpr, F&& f) :
+
+	{}
+
+	template <SizeT L, class Xpr, class F = NoF>
+	template <class PosT>
+	inline decltype(auto) RankAccXpr<L,Xpr,F>::operator()(const PosT& last) const
+	{
+
+	}
+
+	template <SizeT L, class Xpr, class F = NoF>
+	inline decltype(auto) RankAccXpr<L,Xpr,F>::operator()() const
+	{
+
+	}
+
+	template <SizeT L, class Xpr, class F = NoF>
+	template <SizeT I>
+	inline decltype(auto) RankAccXpr<L,Xpr,F>::rootSteps(const IndexId<I>& id) const
+	{
+
+	}
+
+	template <SizeT L, class Xpr, class F = NoF>
+	constexpr decltype(auto) rankaccxpr(SizeT size, const IndexId<L>& id,
+					    const Xpr& xpr, F&& f)
+	{
+	    return RankAccXpr<L,Xpr,F>(size, id, xpr, std::forward<F>(f));
+	}
+    }
+}
+
+#endif
diff --git a/src/opt/mpi/include/racc_xpr.h b/src/opt/mpi/include/racc_xpr.h
new file mode 100644
index 0000000..23b84fd
--- /dev/null
+++ b/src/opt/mpi/include/racc_xpr.h
@@ -0,0 +1,45 @@
+
+// rank access expression, fix rank position to current rank
+
+#ifndef __cxz_mpi_racc_xpr_h__
+#define __cxz_mpi_racc_xpr_h__
+
+#include "mpi_base.h"
+
+namespace CNORXZ
+{
+    namespace mpi
+    {
+
+	template <SizeT L, class Xpr, class F = NoF>
+	class RankAccXpr : public XprInterface<RankAccXpr<L,Xpr,F>>
+	{
+	public:
+	    DEFAULT_MEMBERS(RankAccXpr);
+
+	    constexpr RankAccXpr(SizeT size, const IndexId<L>& id, const Xpr& xpr, F&& f);
+
+	    template <class PosT>
+	    inline decltype(auto) operator()(const PosT& last) const;
+
+	    inline decltype(auto) operator()() const;
+
+	    template <SizeT I>
+	    inline decltype(auto) rootSteps(const IndexId<I>& id) const;
+	    
+	private:
+	    SizeT mSize = 0;
+	    IndexId<L> mId;
+	    Xpr mXpr;
+	    typedef decltype(mXpr.rootSteps(mId)) XPosT;
+	    XPosT mExt;
+	    F mF;
+	};
+
+	template <SizeT L, class Xpr, class F = NoF>
+	constexpr decltype(auto) rankaccxpr(SizeT size, const IndexId<L>& id,
+					    const Xpr& xpr, F&& f);
+    }
+}
+
+#endif