stdlib: Add SparseHist to PyStats

This is inclusive of tests to ensure they have implemented correctly.

Change-Id: I5c84d5ffdb7b914936cfd86ca012a7b141eeaf42

src/test_objects/SConscript

@@ -32,5 +32,6 @@ if env['CONF']['USE_TEST_OBJECTS']:
         'ScalarStatTester',
         'VectorStatTester',
         'Vector2dStatTester',
+        'SparseHistStatTester',
     ])
     Source('stat_tester.cc')

src/test_objects/StatTester.py

@@ -87,3 +87,14 @@ class Vector2dStatTester(StatTester):
         [],
         "The vector stat's y subdescriptions. If empty, the subdescriptions ",
     )
+
+
+class SparseHistStatTester(StatTester):
+    type = "SparseHistStatTester"
+    cxx_header = "test_objects/stat_tester.hh"
+    cxx_class = "gem5::SparseHistStatTester"
+
+    samples = VectorParam.Float(
+        "The sparse histogram's sampled values, to be inserted into the "
+        "histogram."
+    )

src/test_objects/stat_tester.cc

@@ -28,6 +28,8 @@
 
 #include "test_objects/stat_tester.hh"
 
+#include <set>
+
 #include "base/stats/group.hh"
 
 namespace gem5
@@ -133,4 +135,28 @@ Vector2dStatTester::Vector2dStatTesterStats::Vector2dStatTesterStats(
 
 }
 
+void
+SparseHistStatTester::setStats()
+{
+    for (auto sample : params.samples) {
+        stats.sparse_histogram.sample(sample);
+    }
+}
+
+SparseHistStatTester::SparseHistStatTesterStats::SparseHistStatTesterStats(
+    statistics::Group *parent,
+    const SparseHistStatTesterParams &params
+) : statistics::Group(parent),
+    sparse_histogram(
+        this,
+        params.name.c_str(),
+        statistics::units::Count::get(),
+        params.description.c_str()
+    )
+{
+    sparse_histogram.init(
+        (std::set(params.samples.begin(), params.samples.end())).size()
+    );
+}
+
 } // namespace gem5

src/test_objects/stat_tester.hh

@@ -31,6 +31,7 @@
 
 #include "base/statistics.hh"
 #include "params/ScalarStatTester.hh"
+#include "params/SparseHistStatTester.hh"
 #include "params/StatTester.hh"
 #include "params/Vector2dStatTester.hh"
 #include "params/VectorStatTester.hh"
@@ -158,6 +159,27 @@ class Vector2dStatTester : public StatTester
         } stats;
 };
 
+class SparseHistStatTester : public StatTester
+{
+    private:
+        SparseHistStatTesterParams params;
+
+    public:
+        SparseHistStatTester(const SparseHistStatTesterParams &p) :
+            StatTester(p), params(p), stats(this, p) {}
+
+    protected:
+        void setStats() override;
+        struct SparseHistStatTesterStats : public statistics::Group
+        {
+            SparseHistStatTesterStats(
+                statistics::Group *parent,
+                const SparseHistStatTesterParams &params
+            );
+            statistics::SparseHistogram sparse_histogram;
+        } stats;
+};
+
 
 } // namespace gem5