Add exercises

Exercises/src/main/scala/exercises/Top.scala

@@ -0,0 +1,55 @@
+package exercises
+
+import spinal.core._
+import spinal.core.sim._
+
+object PopcntSim {
+  def runSim(width: BitCount, multiCycle: Boolean, input: Int): Unit = {
+    SimConfig.withWave.compile(new Popcnt(width, multiCycle)).doSim {dut =>
+      dut.clockDomain.forkStimulus(10)
+
+      dut.value #= input
+      dut.start #= true
+      dut.clockDomain.waitSampling()
+      dut.start #= false
+
+      while (!dut.ready.toBoolean) {
+        dut.clockDomain.waitSampling()
+      }
+
+      dut.clockDomain.waitSampling()
+      println(s"popcnt($input) = ${dut.count.toBigInt}")
+    }
+  }
+
+  def main(args: Array[String]) {
+    runSim(4 bits, false, 15)
+  }
+}
+
+object ShiftRegSim {
+  def createShiftReg: ShiftReg = {
+    val sr = new ShiftReg
+    sr.addReg("foo", 8 bits, 3)
+    sr.addReg("bar", 16 bits, 5)
+    sr
+  }
+
+  def main(args: Array[String]) {
+    SimConfig.withWave.compile(createShiftReg).doSim {dut =>
+      dut.clockDomain.forkStimulus(10)
+
+      val (fooIn, fooOut) = dut.getReg("foo")
+      val (barIn, barOut) = dut.getReg("bar")
+
+      var tick = 0
+
+      while (tick < 10) {
+        fooIn #= tick
+        barIn #= 10 - tick
+        dut.clockDomain.waitSampling()
+        tick += 1
+      }
+    }
+  }
+}