Starting on implementing ability to allocate subsets of qubit resources

examples/quantum/gate/teleport_scaffold.cpp

@@ -51,14 +51,17 @@ const std::string src("__qpu__ teleport () {\n"
 int main (int argc, char** argv) {
 
 	// Create a convenient alias...
-	using Simple3QubitAcc = xacc::quantum::EigenAccelerator<3>;
+	using Simple6QubitAcc = xacc::quantum::EigenAccelerator<6>;
 
 	// Create a reference to the 3 qubit simulation Accelerator
-	auto qpu = std::make_shared<Simple3QubitAcc>();
+	auto qpu = std::make_shared<Simple6QubitAcc>();
 
 	// Allocate some qubits, give them a unique identifier...
 	auto qreg = qpu->allocate("qreg");
 
+	auto qreg2 = qpu->allocate("qreg", 0, 1, 2);
+
+
 	// Construct a new Program
 	xacc::Program quantumProgram(qpu, src);
 

quantum/gate/accelerators/Qubits.hpp

@@ -20,14 +20,33 @@ protected:
 
 	QubitState state;
 
+	QubitState subState;
+
+	bool usingSubstate;
+
 public:
+
 	Qubits() :
-			state((int) std::pow(2, NumberOfQubits)) {
+			state((int) std::pow(2, NumberOfQubits)), usingSubstate(false) {
 		// Initialize to |000...000> state
 		state.setZero();
 		state(0) = 1.0;
 	}
 
+	template<typename ... ActiveBits>
+	Qubits(QubitState& currentState, ActiveBits ... activeBits) :
+			state(currentState), subState((int) std::pow(2, sizeof...(ActiveBits))),
+			usingSubstate(true) {
+
+	}
+
+	template<typename... SubBits>
+	auto allocateSubset(
+			SubBits... subset) -> decltype(std::shared_ptr<Qubits<sizeof...(SubBits)>>()) {
+		auto qubits = std::make_shared<Qubits<sizeof...(SubBits)>>(state, subset...);
+		return qubits;
+	}
+
 	void applyUnitary(Eigen::MatrixXcd& U) {
 		state = U * state;
 	}

quantum/gate/accelerators/eigenaccelerator/EigenAccelerator.hpp

@@ -48,7 +48,7 @@ using QuantumGraphIR = xacc::GraphIR<GraphType>;
  *
  */
 template<const int NQubits>
-class EigenAccelerator : public QPUGate<NQubits> {
+class EigenAccelerator : virtual public QPUGate<NQubits> {
 public:
 
 	/**
@@ -265,4 +265,5 @@ protected:
 
 
 
+
 #endif

quantum/gate/accelerators/tests/QubitsTester.cpp

@@ -41,6 +41,6 @@ BOOST_AUTO_TEST_CASE(checkConstruction) {
 	Qubits<3> qubits;
 	BOOST_VERIFY(qubits.N == 3);
 	std::bitset<3> bits;
-	BOOST_VERIFY(bits == qubits.toBits());
+	BOOST_VERIFY(bits == qubits.measure());
 }
 

quantum/gate/compilers/scaffold/ScaffoldCompiler.cpp

@@ -53,12 +53,13 @@ void ScaffoldCompiler::modifySource() {
 	std::map<int, int> cbitToQubit;
 
 	std::regex qbitName("qbit\\s.*");
-	qubitAllocationLine = (*std::sregex_iterator(kernelSource.begin(), kernelSource.end(),
-				qbitName)).str() + "\n";
-	  std::vector<std::string> splitQbit;
-	    boost::split(splitQbit, qubitAllocationLine, boost::is_any_of(" "));
+	qubitAllocationLine = (*std::sregex_iterator(kernelSource.begin(),
+			kernelSource.end(), qbitName)).str() + "\n";
+	std::vector<std::string> splitQbit;
+	boost::split(splitQbit, qubitAllocationLine, boost::is_any_of(" "));
     auto qbitVarName = splitQbit[1].substr(0, splitQbit[1].find_first_of("["));
 
+    // Create Cbit to Qbit mapping
 	std::regex cbitName("cbit\\s.*");
 	auto it = std::sregex_iterator(kernelSource.begin(), kernelSource.end(),
 			cbitName);
@@ -168,10 +169,6 @@ std::shared_ptr<IR> ScaffoldCompiler::compile() {
 	// This will throw if it fails.
 	auto qasm = scaffcc.getFlatQASMFromSource(kernelSource);
 
-	// Generate a GraphIR instance, ie a graph
-	// tensor references making up this QASM
-//	std::cout << "Flat QASM: \n" << qasm << "\n";
-
 	// Get the Qasm as a Graph...
 	auto circuitGraph = QasmToGraph::getCircuitGraph(qasm);
 

quantum/gate/utils/QasmToGraph.hpp

@@ -185,20 +185,6 @@ public:
 		// Set how many layers are in this circuit
 		int maxLayer = layer+1;
 
-		// Print info...
-//		for (auto cn : gateOperations) {
-//			std::cout << "Gate Operation: \n";
-//			std::cout << "\tName: " << std::get<0>(cn.properties) << "\n";
-//			std::cout << "\tLayer: " << std::get<1>(cn.properties) << "\n";
-//			std::cout << "\tGate Vertex Id: " << std::get<2>(cn.properties) << "\n";
-//			std::cout << "\tActing Qubits: ";
-//			std::vector<int> qubits = std::get<3>(cn.properties);
-//			for (auto v : qubits) {
-//				std::cout << v << ", ";
-//			}
-//			std::cout << "\n\n";
-//		}
-
 		generateEdgesFromLayer(1, graph, gateOperations, 0);
 
 		return graph;
@@ -214,7 +200,8 @@ public:
 	 * @param conditionalGraphs
 	 */
 	static void linkConditionalQasm(qci::common::Graph<CircuitNode>& mainGraph,
-			std::vector<qci::common::Graph<CircuitNode>>& conditionalGraphs, std::vector<int>& conditionalQubits) {
+			std::vector<qci::common::Graph<CircuitNode>>& conditionalGraphs,
+			std::vector<int>& conditionalQubits) {
 
 		// At this point we have a main circuit graph,
 		// and one or more smaller conditional graphs (each with

xacc/accelerator/Accelerator.hpp

@@ -78,19 +78,26 @@ public:
 	 * Return the current state of the bits
 	 * @return
 	 */
-	virtual std::bitset<(size_t) Number> toBits() {
+	virtual std::bitset<(size_t) Number> measure() {
 		return bits;
 	}
 
+	template<typename... SubBits>
+	auto allocateSubset(
+			SubBits ... subset) ->
+			decltype(std::shared_ptr<AcceleratorBits<sizeof...(SubBits)>>()) {
+	}
 	virtual ~AcceleratorBits() {}
 
-private:
+protected:
 
 	/**
 	 *  The bits themselves
 	 */
 	std::bitset<(size_t)Number> bits;
 
+	std::vector<int> activeBits;
+
 };
 
 class IAccelerator : public qci::common::QCIObject {
@@ -146,11 +153,11 @@ public:
  * instances that transform XACC IR to be amenable to execution
  * on the hardware.
  */
-template<typename BitsType>
+template<typename TotalBits>
 class Accelerator : public IAccelerator {
 
-	static_assert(is_valid_bitstype<BitsType>::value, "Derived BitsType parameter must contain N int member for number of bits.");
-	static_assert(std::is_base_of<AcceleratorBits<BitsType::N>, BitsType>::value, "");
+	static_assert(is_valid_bitstype<TotalBits>::value, "Derived BitsType parameter must contain N int member for number of bits.");
+	static_assert(std::is_base_of<AcceleratorBits<TotalBits::N>, TotalBits>::value, "");
 
 public:
 
@@ -159,16 +166,38 @@ public:
 	 *
 	 * @return bits The AcceleratorBits derived type
 	 */
-	std::shared_ptr<BitsType> allocate(const std::string& variableNameId) {
-		if (!canAllocate(BitsType::N)) {
+	std::shared_ptr<TotalBits> allocate(const std::string& variableNameId) {
+		if (!canAllocate(TotalBits::N)) {
 			QCIError("Error in allocated requested bits");
 		}
-		bits = std::make_shared<BitsType>();
-		NBitsAllocated = BitsType::N;
+		bits = std::make_shared<TotalBits>();
+		NBitsAllocated = TotalBits::N;
 		bitVarId = variableNameId;
 		return bits;
 	}
 
+	/**
+	 * Allocate some subset of Accelerator bit resources.
+	 *
+	 * @param variableNameId
+	 * @param bitList
+	 * @return
+	 */
+	template<typename... SubBits>
+	auto allocate(const std::string& variableNameId,
+			SubBits... bitList) -> decltype(std::declval<TotalBits>().allocateSubset(bitList...)) {
+		// FIXME CHECK THAT THEY PASSED IN LIST OF INTS
+		if (!canAllocate(sizeof...(SubBits))) {
+			QCIError("Error in allocated requested bits");
+		}
+
+		auto subsetBits = bits->allocateSubset(bitList...);
+		NBitsAllocated = (int) sizeof...(SubBits);
+		bitVarId = variableNameId;
+
+		return subsetBits;
+	}
+
 	/**
 	 * Return the number of bits that the user most recently
 	 * requested.
@@ -210,7 +239,7 @@ protected:
 	/**
 	 *
 	 */
-	std::shared_ptr<BitsType> bits;
+	std::shared_ptr<TotalBits> bits;
 
 	/**
 	 * Return true if this Accelerator can allocate

xacc/compiler/Compiler.hpp

@@ -36,7 +36,6 @@
 #include "AbstractFactory.hpp"
 #include "QCIError.hpp"
 #include "IR.hpp"
-#include "Accelerator.hpp"
 #include <ostream>
 
 using namespace qci::common;