Fixed measurement conditional graph ordering bug (#3)

quantum/gate/compilers/scaffold/ScaffoldCompiler.cpp

@@ -49,11 +49,47 @@ void ScaffoldCompiler::modifySource() {
 	kernelSource.erase(kernelSource.find("__qpu__"), 7);
 	kernelSource = std::string("module ") + kernelSource;
 
-	std::string qubitAllocationLine;// = "   qbit qreg[3];\n";
+	std::string qubitAllocationLine, cbitAllocationLine;// = "   qbit qreg[3];\n";
 
 	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(" "));
+    auto qbitVarName = splitQbit[1].substr(0, splitQbit[1].find_first_of("["));
+
+    std::regex cbitName("cbit\\s.*");
+    cbitAllocationLine = (*std::sregex_iterator(kernelSource.begin(), kernelSource.end(),
+                            cbitName)).str() + "\n";
+    std::vector<std::string> splitCbit;
+    boost::split(splitCbit, cbitAllocationLine, boost::is_any_of(" "));
+    auto cbitVarName = splitCbit[1].substr(0, splitCbit[1].find_first_of("["));
+
+    std::regex measurements(".*Meas.*");
+    std::map<int, int> cbitToQubit;
+    for (auto i = std::sregex_iterator(kernelSource.begin(), kernelSource.end(),
+                    measurements); i != std::sregex_iterator(); ++i) {
+            auto measurement = (*i).str();
+            boost::trim(measurement);
+
+            boost::erase_all(measurement, "MeasZ");
+            boost::erase_all(measurement, "(");
+            boost::erase_all(measurement, ")");
+            boost::erase_all(measurement, cbitVarName);
+            boost::erase_all(measurement, qbitVarName);
+            // Should now have [#] = [#]
+            boost::erase_all(measurement, "[");
+            boost::erase_all(measurement, "]");
+
+            std::vector<std::string> splitVec;
+            boost::split(splitVec, measurement, boost::is_any_of("="));
+            auto cbit = splitVec[0];
+            auto qbit = splitVec[1];
+            boost::trim(cbit);
+            boost::trim(qbit);
+
+            cbitToQubit.insert(std::make_pair(std::stoi(cbit), std::stoi(qbit)));
+    }
 
 	// conditional on measurements
 	// FIXME FOR NOW WE ONLY ACCEPT format
@@ -73,12 +109,28 @@ void ScaffoldCompiler::modifySource() {
 		counter++;
 
 		ifLines.push_back(ifLine + ";\n");
-	}
 
-	for (auto s : conditionalCodeSegments) {
-		std::cout << s << "\n";
+        // Also get which cbit this conditional code belongs to
+		int measurementGateId = -1;
+		for (auto s : splitVec) {
+			if (boost::contains(s, cbitVarName)) {
+				boost::erase_all(s, "(");
+
+				boost::erase_all(s, cbitVarName);
+				boost::erase_all(s, "[");
+				boost::erase_all(s, "]");
+
+				conditionalCodeSegmentActingQubits.push_back(cbitToQubit[std::stoi(s)]);
+
+				break;
+			}
+		}
+
 	}
 
+	// Erase the if lines from the main source
+	// they are going to be represented with
+	// conditional graphs.
 	for (auto s : ifLines) {
 		auto idx = kernelSource.find(s);
 		kernelSource.erase(idx, s.size());
@@ -94,7 +146,7 @@ void ScaffoldCompiler::modifySource() {
 	kernelSource = kernelSource + std::string("\nint main() {\n   ") + fName
 			+ std::string(");\n}");
 
-	std::cout << "\n" << kernelSource << "\n";
+//	std::cout << "\n" << kernelSource << "\n";
 }
 
 std::shared_ptr<IR> ScaffoldCompiler::compile() {
@@ -111,7 +163,7 @@ std::shared_ptr<IR> ScaffoldCompiler::compile() {
 
 	// Generate a GraphIR instance, ie a graph
 	// tensor references making up this QASM
-	std::cout << "Flat QASM: \n" << qasm << "\n";
+//	std::cout << "Flat QASM: \n" << qasm << "\n";
 
 	// Get the Qasm as a Graph...
 	auto circuitGraph = QasmToGraph::getCircuitGraph(qasm);
@@ -122,6 +174,8 @@ std::shared_ptr<IR> ScaffoldCompiler::compile() {
 	// the addition of a COND conditional node that will enable the
 	// conditional nodes if the measured cbit is a 1.
 
+	// Get measurement acting qubits
+
 	// So a COND node needs to know the gate id of the measurement gate
 	// and the nodes to mark enabled if the measurement is a 1,
 	if (!conditionalCodeSegments.empty()) {
@@ -132,7 +186,8 @@ std::shared_ptr<IR> ScaffoldCompiler::compile() {
 			condGraphs.push_back(g);
 		}
 
-		QasmToGraph::linkConditionalQasm(circuitGraph, condGraphs);
+		QasmToGraph::linkConditionalQasm(circuitGraph, condGraphs,
+				conditionalCodeSegmentActingQubits);
 	}
 
 	// Create a GraphIR instance from that graph

quantum/gate/compilers/scaffold/ScaffoldCompiler.hpp

@@ -86,6 +86,7 @@ protected:
 	 * Reference to potential conditional code
 	 */
 	std::vector<std::string> conditionalCodeSegments;
+	std::vector<int> conditionalCodeSegmentActingQubits;
 
 };
 

quantum/gate/utils/QasmToGraph.hpp

@@ -214,7 +214,7 @@ public:
 	 * @param conditionalGraphs
 	 */
 	static void linkConditionalQasm(qci::common::Graph<CircuitNode>& mainGraph,
-			std::vector<qci::common::Graph<CircuitNode>> conditionalGraphs) {
+			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
@@ -224,18 +224,7 @@ public:
 		// pull out the gate vertices (skip initial final state nodes)
 		// and add them to the main graph after some conditional nodes
 
-		// NOTE We assume that the ith conditionalGraph corresponds to the ith
-		// measurement gate... WRONG!!!!
-		std::vector<int> measurementIds;
-		std::vector<std::vector<int>>measurementQubits;
-		for (int i = 0; i < mainGraph.order(); i++) {
-			if (mainGraph.getVertexProperty<0>(i) == "measure") {
-				measurementIds.push_back(mainGraph.getVertexProperty<2>(i));
-				measurementQubits.push_back(mainGraph.getVertexProperty<3>(i));
-			}
-		}
-
-		assert (measurementIds.size() == conditionalGraphs.size());
+		assert (conditionalQubits.size() == conditionalGraphs.size());
 
 		int counter = 0;
 		int finalIdMainGraph = mainGraph.getVertexProperty<2>(mainGraph.order() - 1);
@@ -250,8 +239,8 @@ public:
 		for (auto g : conditionalGraphs) {
 			CircuitNode node;
 			std::get<0>(node.properties) = "conditional";
-			std::get<2>(node.properties) = id;//measurementIds[counter];
-			std::get<3>(node.properties) = measurementQubits[counter];
+			std::get<2>(node.properties) = id;
+			std::get<3>(node.properties) = std::vector<int> {conditionalQubits[counter]};
 			mainGraph.addVertex(node);
 
 			// Connect the main graph to the cond node

xacc/program/Program.hpp

@@ -64,7 +64,6 @@ std::vector<IRTransformation> getAcceleratorIndependentTransformations(
  * Accelerator reference to be used and kernel source
  * code at construction time.
  */
-//template<typename AccType>
 class Program {
 
 protected:
@@ -147,7 +146,6 @@ public:
 		auto bitTypeStr = compiler->getBitType();
 		auto nBits = accelerator->getAllocationSize();
 		auto varName = accelerator->getVariableName();
-		std::cout << "HELLO WORLD: " << nBits << ", " << varName << "\n";
 		std::string bitAllocationSrc = bitTypeStr + " " + varName + "["
 				+ std::to_string(nBits) + "];\n";
 
@@ -202,7 +200,6 @@ public:
 	std::function<void(RuntimeArgs...)> getKernel(const std::string& name,
 			RuntimeArgs ... args) {
 		return [&]() {
-			std::cout << "HELLO WORLD FROM KERNEL\n";
 			accelerator->execute(xaccIR, args...);
 			return;
 		};