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+#include "model/electrical/BarrelShifter.h"
+#include "model/electrical/Multiplexer.h"
+
+#include <cmath>
+
+#include "model/PortInfo.h"
+#include "model/TransitionInfo.h"
+#include "model/EventInfo.h"
+#include "model/timing_graph/ElectricalDriverMultiplier.h"
+#include "model/timing_graph/ElectricalNet.h"
+#include "model/std_cells/StdCell.h"
+#include "model/std_cells/StdCellLib.h"
+
+namespace DSENT
+{
+ BarrelShifter::BarrelShifter(const String& instance_name_, const TechModel* tech_model_)
+ : ElectricalModel(instance_name_, tech_model_)
+ {
+ initParameters();
+ initProperties();
+ }
+
+ BarrelShifter::~BarrelShifter()
+ {}
+
+ void BarrelShifter::initParameters()
+ {
+ addParameterName("NumberBits");
+ addParameterName("ShiftIndexMin");
+ addParameterName("ShiftIndexMax");
+ addParameterName("BitDuplicate", "TRUE");
+ return;
+ }
+
+ void BarrelShifter::initProperties()
+ {
+ return;
+ }
+
+ BarrelShifter* BarrelShifter::clone() const
+ {
+ return NULL;
+ }
+
+ void BarrelShifter::constructModel()
+ {
+ // Get parameters
+ unsigned int number_bits = getParameter("NumberBits");
+ unsigned int number_shift_bits = (unsigned int)ceil(log2((double) number_bits));
+ unsigned int shift_index_min = getParameter("ShiftIndexMin");
+ unsigned int shift_index_max = getParameter("ShiftIndexMax");
+ bool bit_duplicate = (bool) getParameter("BitDuplicate");
+
+ ASSERT(number_bits > 0, "[Error] " + getInstanceName() + " -> Number of bits must be > 0!");
+ // No need to check these if there arent any shifts
+ if (number_shift_bits > 0)
+ {
+ ASSERT(shift_index_min <= number_shift_bits,
+ "[Error] " + getInstanceName() + " -> Min shift index must be >= 0 and <= " +
+ "the total number of shift bits!");
+ ASSERT(shift_index_max >= shift_index_min && shift_index_max <= number_shift_bits,
+ "[Error] " + getInstanceName() + " -> Max shift index must be >= minimum shift index and <= " +
+ "the total number of shift bits!");
+ }
+
+ //Construct electrical ports
+ //Create each input port
+ createInputPort( "In", makeNetIndex(0, number_bits-1));
+ //Create output
+ createOutputPort( "Out", makeNetIndex(0, number_bits-1));
+
+ //Create shift ports (which only exists if there is something to shift)
+ if (shift_index_min != number_shift_bits)
+ for (unsigned int i = shift_index_min; i <= shift_index_max; ++i)
+ createInputPort( "Shift" + (String) i);
+
+ //Create energy, power, and area results
+ createElectricalResults();
+ createElectricalEventResult("BarrelShift");
+ //Set conditions during idle event
+ getEventInfo("Idle")->setStaticTransitionInfos();
+
+ //If the input is only 1-bit, connect input to output and be done
+ if (number_shift_bits == 0 || (shift_index_min == number_shift_bits))
+ assign("Out", "In");
+ else
+ {
+ for (unsigned int i = shift_index_min; i <= shift_index_max; ++i)
+ {
+ //Create internally buffered shift select signals
+ createNet("Shift_b" + (String) i);
+ createNet("Shift_i" + (String) i);
+ }
+
+ // Create shift and shifted signals
+ for (unsigned int i = shift_index_min; i <= shift_index_max; ++i)
+ {
+ unsigned int current_shifts = (unsigned int)pow(2, i);
+ const String& n = (String) current_shifts;
+ //Instantiate and connect intermediate nets. In a barrel-shifter, the nets do
+ //all the "shifting" and the muxes just select which to take
+ createNet("R_" + n, makeNetIndex(0, number_bits-1)); //wire R_n[number_bits-1:0]
+ createNet("RS_" + n, makeNetIndex(0, number_bits-1)); //wire RS_n[number_bits-1:0]
+
+ //Implements the shifts
+ //assign RS_n[number_bits-1:number_bits-current_shifts] = R_n[current_shifts-1:0];
+ assign("RS_" + n, makeNetIndex(number_bits-current_shifts, number_bits-1),
+ "R_" + n, makeNetIndex(0, current_shifts-1));
+ //assign RS_n[number_bits-current_shifts-1:0] = R_n[current_shifts:number_bits-1];
+ assign("RS_" + n, makeNetIndex(0, number_bits-current_shifts-1),
+ "R_" + n, makeNetIndex(current_shifts, number_bits-1));
+ }
+
+ const String& n_max = (String) pow(2, shift_index_max+1);
+ const String& n_min = (String) pow(2, shift_index_min);
+ // Create the R_(max) net
+ createNet("R_" + n_max, makeNetIndex(0, number_bits-1));
+ // Set R_1 to be the input
+ assign("R_" + n_min, "In");
+ // Set R_(max) to be the output
+ assign("Out", "R_" + n_max, makeNetIndex(0, number_bits-1));
+
+ for (unsigned int i = shift_index_min; i <= shift_index_max; ++i)
+ {
+ unsigned int current_shifts = (unsigned int)pow(2, i);
+ const String& n = (String) current_shifts;
+ const String& n_next = (String) (current_shifts * 2);
+
+ const String& buf_inv_0_name = "ShiftBufInv0_" + (String) n;
+ const String& buf_inv_1_name = "ShiftBufInv1_" + (String) n;
+ // Create shift buffer inverters
+ StdCell* buf_inv_0 = getTechModel()->getStdCellLib()->createStdCell("INV", buf_inv_0_name);
+ buf_inv_0->construct();
+ StdCell* buf_inv_1 = getTechModel()->getStdCellLib()->createStdCell("INV", buf_inv_1_name);
+ buf_inv_1->construct();
+
+ // Connect up shift buffer inverters
+ portConnect(buf_inv_0, "A", "Shift" + (String) i);
+ portConnect(buf_inv_0, "Y", "Shift_b" + (String) i);
+ portConnect(buf_inv_1, "A", "Shift_b" + (String) i);
+ portConnect(buf_inv_1, "Y", "Shift_i" + (String) i);
+
+ // Add area, power, and event results for inverters
+ addSubInstances(buf_inv_0, 1.0);
+ addSubInstances(buf_inv_1, 1.0);
+ addElectricalSubResults(buf_inv_0, 1.0);
+ addElectricalSubResults(buf_inv_1, 1.0);
+ getEventResult("BarrelShift")->addSubResult(buf_inv_0->getEventResult("INV"), buf_inv_0_name, 1.0);
+ getEventResult("BarrelShift")->addSubResult(buf_inv_1->getEventResult("INV"), buf_inv_1_name, 1.0);
+
+ //Instantiate 2:1 multiplexers, one for each shift bit.
+ const String& mux_name = "SRL" + n;
+ Multiplexer* mux = new Multiplexer(mux_name, getTechModel());
+ mux->setParameter("NumberInputs", 2);
+ mux->setParameter("NumberBits", number_bits);
+ mux->setParameter("BitDuplicate", bit_duplicate);
+ mux->construct();
+
+ //Just have to connect the In0 and In1 inputs of the mux to the
+ //non-shifted and shifted intermediate signals, respectively.
+ portConnect(mux, "In0", "R_" + n);
+ portConnect(mux, "In1", "RS_" + n);
+ //Selector connects to the shift signal for that index
+ portConnect(mux, "Sel0", "Shift_i" + (String) i);
+ //Connect mux output
+ portConnect(mux, "Out", "R_" + n_next);
+
+ //Add area, power, and event results for each mux
+ addSubInstances(mux, 1.0);
+ addElectricalSubResults(mux, 1.0);
+ getEventResult("BarrelShift")->addSubResult(mux->getEventResult("Mux"), mux_name, 1.0);
+ }
+ }
+ return;
+ }
+
+ void BarrelShifter::propagateTransitionInfo()
+ {
+ // The only thing can be updated are the input probabilities...so we will update them
+ unsigned int number_bits = (unsigned int) getParameter("NumberBits");
+ unsigned int number_shift_bits = (unsigned int) ceil(log2((double) number_bits));
+ unsigned int shift_index_min = getParameter("ShiftIndexMin");
+ unsigned int shift_index_max = getParameter("ShiftIndexMax");
+
+ // Keep track of the multiplexer of the last stage
+ ElectricalModel* last_mux = NULL;
+ // We only need to update stuff if we are not shifting by exact multiples
+ // of number of input bits
+ if (shift_index_min < number_shift_bits)
+ {
+ for (unsigned int i = shift_index_min; i <= shift_index_max; ++i)
+ {
+ unsigned int current_shifts = (unsigned int)pow(2, i);
+ String n = (String) current_shifts;
+
+ // Set the
+ const String& buf_inv_0_name = "ShiftBufInv0_" + (String) n;
+ const String& buf_inv_1_name = "ShiftBufInv1_" + (String) n;
+ const String& mux_name = "SRL" + n;
+
+ // Set the transition infos for the inverter buffers
+ ElectricalModel* buf_inv_0 = (ElectricalModel*) getSubInstance(buf_inv_0_name);
+ propagatePortTransitionInfo(buf_inv_0, "A", "Shift" + (String) i);
+ buf_inv_0->use();
+
+ ElectricalModel* buf_inv_1 = (ElectricalModel*) getSubInstance(buf_inv_1_name);
+ propagatePortTransitionInfo(buf_inv_1, "A", buf_inv_0, "Y");
+ buf_inv_1->use();
+
+ // Set the transition infos for the shift multiplexers
+ ElectricalModel* mux = (ElectricalModel*) getSubInstance(mux_name);
+ propagatePortTransitionInfo(mux, "Sel0", buf_inv_1, "Y");
+ if (last_mux == NULL)
+ {
+ propagatePortTransitionInfo(mux, "In0", "In");
+ propagatePortTransitionInfo(mux, "In1", "In");
+ }
+ else
+ {
+ propagatePortTransitionInfo(mux, "In0", last_mux, "Out");
+ propagatePortTransitionInfo(mux, "In1", last_mux, "Out");
+ }
+ mux->use();
+
+ // Set this to be the last mux visted
+ last_mux = mux;
+ }
+ }
+
+ // If there isn't anything to shift
+ if (last_mux == NULL)
+ propagatePortTransitionInfo("Out", "In");
+ // Take the transition info of the last mux
+ else
+ propagatePortTransitionInfo("Out", last_mux, "Out");
+
+ return;
+ }
+
+} // namespace DSENT
+
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