ext: add the source code for DSENT

This patch adds a tool called DSENT to the ext/ directory.  DSENT
is a tool that models power and area for on-chip networks.  The next
patch adds a script for using the tool.

1 files changed, 57 insertions, 0 deletions

diff --git a/ext/dsent/model/optical_graph/OpticalWavelength.h b/ext/dsent/model/optical_graph/OpticalWavelength.h
new file mode 100644
index 000000000..6a5f31e9a
--- /dev/null
+++ b/ext/dsent/model/optical_graph/OpticalWavelength.h
@@ -0,0 +1,57 @@
+#ifndef __DSENT_MODEL_OPTICALGRAPH_OPTICALWAVELENGTH_H__
+#define __DSENT_MODEL_OPTICALGRAPH_OPTICALWAVELENGTH_H__
+
+#include "model/OpticalModel.h"
+#include "util/CommonType.h"
+
+namespace DSENT
+{
+    // Optical datapath structure storing a detector table consisting of a
+    // detector, the loss to that detector, and the modulator driving
+    // the wavelength for that detector
+    struct OpticalDataPath
+    {
+        OpticalLaser* laser;
+        OpticalModulator* modulator;
+        vector<OpticalDetector*> detectors;
+        vector<double> losses;
+        
+        OpticalDataPath(OpticalLaser* laser_, OpticalModulator* modulator_, OpticalDetector* detector_, double loss_)
+            : laser(laser_), modulator(modulator_), detectors(1, detector_), losses(1, loss_) {}
+    };
+
+    class OpticalWavelength
+    {
+        // A data structure of a wavelength (or a group of wavelengths). This
+        // keeps track of all lasers sources, modulators, and detectors that
+        // the wavelength hits.
+        public:
+            OpticalWavelength(const String& instance_name_, const WavelengthGroup& wavelengths_);
+            ~OpticalWavelength();
+
+        public:
+            // Get tree name
+            const String& getInstanceName() const;
+            // Get wavelength groups
+            WavelengthGroup getWavelengths() const;
+            // Add a datapath for this wavelength
+            void addDataPath(OpticalLaser* laser_, OpticalModulator* modulator_, OpticalDetector* detector_, double loss_);
+            const vector<OpticalDataPath>* getDataPaths() const;
+            // Calculate required wavelength power to reach some number of detectors
+            // If number_detectors < the number of total detectors this wavelength hits then
+            // it simply returns the laser power required to reach the worst-case detectors
+            double getLaserPower(unsigned int number_detectors_) const;
+        
+        private:
+            // Name of the wavelength
+            const String m_instance_name_;
+            // Keeps track of the wavelengths
+            const WavelengthGroup m_wavelengths_;
+            // Keeps track of a table of laser, detector, modulator mappings
+            vector<OpticalDataPath>* m_data_paths_;            
+    };
+    
+} // namespace DSENT
+
+#endif // __DSENT_MODEL_OPTICALGRAPH_OPTICALWAVEGUIDE_H__
+