Add light shifter plugin

src/main/scala/SpinalRiscv/Pipeline.scala

@@ -92,7 +92,7 @@ trait Pipeline {
             inputDefault := stage.inserts(key)
           } else {
             val stageBefore = stages(stageIndex - 1)
-            inputDefault := RegNextWhen(stageBefore.output(key), !stageBefore.arbitration.isStuck) //!stage.input.valid || stage.input.ready
+            inputDefault := RegNextWhen(stageBefore.output(key), !stage.arbitration.isStuck) //!stage.input.valid || stage.input.ready
           }
         }
       }

src/main/scala/SpinalRiscv/Plugin/FullBarrielShifterPlugin.scala

@@ -1,83 +0,0 @@
-package SpinalRiscv.Plugin
-
-import SpinalRiscv._
-import spinal.core._
-import spinal.lib.Reverse
-
-
-
-class FullBarrielShifterPlugin extends Plugin[VexRiscv]{
-  object ShiftCtrlEnum extends SpinalEnum(binarySequential){
-    val DISABLE, SLL, SRL, SRA = newElement()
-  }
-
-  object SHIFT_CTRL extends Stageable(ShiftCtrlEnum())
-  object SHIFT_RIGHT extends Stageable(Bits(32 bits))
-
-  override def setup(pipeline: VexRiscv): Unit = {
-    import Riscv._
-    import pipeline.config._
-
-
-
-    val immediateActions = List[(Stageable[_ <: BaseType],Any)](
-      LEGAL_INSTRUCTION        -> True,
-      SRC1_CTRL                -> Src1CtrlEnum.RS,
-      SRC2_CTRL                -> Src2CtrlEnum.IMI,
-      REGFILE_WRITE_VALID      -> True,
-      BYPASSABLE_EXECUTE_STAGE -> False,
-      BYPASSABLE_MEMORY_STAGE  -> True,
-      REG1_USE                 -> True
-    )
-
-    val nonImmediateActions = List[(Stageable[_ <: BaseType],Any)](
-      LEGAL_INSTRUCTION        -> True,
-      SRC1_CTRL                -> Src1CtrlEnum.RS,
-      SRC2_CTRL                -> Src2CtrlEnum.RS,
-      REGFILE_WRITE_VALID      -> True,
-      BYPASSABLE_EXECUTE_STAGE -> False,
-      BYPASSABLE_MEMORY_STAGE  -> True,
-      REG1_USE                 -> True,
-      REG2_USE                 -> True
-    )
-
-    val decoderService = pipeline.service(classOf[DecoderService])
-    decoderService.addDefault(SHIFT_CTRL, ShiftCtrlEnum.DISABLE)
-    decoderService.add(List(
-      SLL  -> (nonImmediateActions ++ List(SHIFT_CTRL -> ShiftCtrlEnum.SLL)),
-      SRL  -> (nonImmediateActions ++ List(SHIFT_CTRL -> ShiftCtrlEnum.SRL)),
-      SRA  -> (nonImmediateActions ++ List(SHIFT_CTRL -> ShiftCtrlEnum.SRA))
-    ))
-
-    decoderService.add(List(
-      SLLI  -> (immediateActions ++ List(SHIFT_CTRL -> ShiftCtrlEnum.SLL)),
-      SRLI  -> (immediateActions ++ List(SHIFT_CTRL -> ShiftCtrlEnum.SRL)),
-      SRAI  -> (immediateActions ++ List(SHIFT_CTRL -> ShiftCtrlEnum.SRA))
-    ))
-  }
-
-  override def build(pipeline: VexRiscv): Unit = {
-    import pipeline._
-    import pipeline.config._
-
-
-    execute plug new Area{
-      import execute._
-      val amplitude  = input(SRC2)(4 downto 0).asUInt
-      val reversed   = Mux(input(SHIFT_CTRL) === ShiftCtrlEnum.SLL, Reverse(input(SRC1)), input(SRC1))
-      insert(SHIFT_RIGHT) := (Cat(input(SHIFT_CTRL) === ShiftCtrlEnum.SRA & reversed.msb, reversed).asSInt >> amplitude)(31 downto 0).asBits
-    }
-
-    memory plug new Area{
-      import memory._
-      switch(input(SHIFT_CTRL)){
-        is(ShiftCtrlEnum.SLL){
-          output(REGFILE_WRITE_DATA) := Reverse(input(SHIFT_RIGHT))
-        }
-        is(ShiftCtrlEnum.SRL,ShiftCtrlEnum.SRA){
-          output(REGFILE_WRITE_DATA) := input(SHIFT_RIGHT)
-        }
-      }
-    }
-  }
-}

src/main/scala/SpinalRiscv/Plugin/IntAluPlugin.scala

@@ -2,15 +2,17 @@ package SpinalRiscv.Plugin
 
 import SpinalRiscv._
 import spinal.core._
-
+object IntAluPlugin{
-
-class IntAluPlugin extends Plugin[VexRiscv]{
-
   object AluCtrlEnum extends SpinalEnum(binarySequential){
     val ADD_SUB, SLT_SLTU, XOR, OR, AND, SRC1 = newElement()
   }
 
   object ALU_CTRL extends Stageable(AluCtrlEnum())
+}
+
+class IntAluPlugin extends Plugin[VexRiscv]{
+  import IntAluPlugin._
+
 
   override def setup(pipeline: VexRiscv): Unit = {
     import Riscv._

src/main/scala/SpinalRiscv/Plugin/ShiftPlugins.scala

@@ -0,0 +1,172 @@
+package SpinalRiscv.Plugin
+
+import SpinalRiscv._
+import spinal.core._
+import spinal.lib.Reverse
+
+
+
+class FullBarrielShifterPlugin extends Plugin[VexRiscv]{
+  object ShiftCtrlEnum extends SpinalEnum(binarySequential){
+    val DISABLE, SLL, SRL, SRA = newElement()
+  }
+
+  object SHIFT_CTRL extends Stageable(ShiftCtrlEnum())
+  object SHIFT_RIGHT extends Stageable(Bits(32 bits))
+
+  override def setup(pipeline: VexRiscv): Unit = {
+    import Riscv._
+    import pipeline.config._
+
+
+
+    val immediateActions = List[(Stageable[_ <: BaseType],Any)](
+      LEGAL_INSTRUCTION        -> True,
+      SRC1_CTRL                -> Src1CtrlEnum.RS,
+      SRC2_CTRL                -> Src2CtrlEnum.IMI,
+      REGFILE_WRITE_VALID      -> True,
+      BYPASSABLE_EXECUTE_STAGE -> False,
+      BYPASSABLE_MEMORY_STAGE  -> True,
+      REG1_USE                 -> True
+    )
+
+    val nonImmediateActions = List[(Stageable[_ <: BaseType],Any)](
+      LEGAL_INSTRUCTION        -> True,
+      SRC1_CTRL                -> Src1CtrlEnum.RS,
+      SRC2_CTRL                -> Src2CtrlEnum.RS,
+      REGFILE_WRITE_VALID      -> True,
+      BYPASSABLE_EXECUTE_STAGE -> False,
+      BYPASSABLE_MEMORY_STAGE  -> True,
+      REG1_USE                 -> True,
+      REG2_USE                 -> True
+    )
+
+    val decoderService = pipeline.service(classOf[DecoderService])
+    decoderService.addDefault(SHIFT_CTRL, ShiftCtrlEnum.DISABLE)
+    decoderService.add(List(
+      SLL  -> (nonImmediateActions ++ List(SHIFT_CTRL -> ShiftCtrlEnum.SLL)),
+      SRL  -> (nonImmediateActions ++ List(SHIFT_CTRL -> ShiftCtrlEnum.SRL)),
+      SRA  -> (nonImmediateActions ++ List(SHIFT_CTRL -> ShiftCtrlEnum.SRA))
+    ))
+
+    decoderService.add(List(
+      SLLI  -> (immediateActions ++ List(SHIFT_CTRL -> ShiftCtrlEnum.SLL)),
+      SRLI  -> (immediateActions ++ List(SHIFT_CTRL -> ShiftCtrlEnum.SRL)),
+      SRAI  -> (immediateActions ++ List(SHIFT_CTRL -> ShiftCtrlEnum.SRA))
+    ))
+  }
+
+  override def build(pipeline: VexRiscv): Unit = {
+    import pipeline._
+    import pipeline.config._
+
+
+    execute plug new Area{
+      import execute._
+      val amplitude  = input(SRC2)(4 downto 0).asUInt
+      val reversed   = Mux(input(SHIFT_CTRL) === ShiftCtrlEnum.SLL, Reverse(input(SRC1)), input(SRC1))
+      insert(SHIFT_RIGHT) := (Cat(input(SHIFT_CTRL) === ShiftCtrlEnum.SRA & reversed.msb, reversed).asSInt >> amplitude)(31 downto 0).asBits
+    }
+
+    memory plug new Area{
+      import memory._
+      switch(input(SHIFT_CTRL)){
+        is(ShiftCtrlEnum.SLL){
+          output(REGFILE_WRITE_DATA) := Reverse(input(SHIFT_RIGHT))
+        }
+        is(ShiftCtrlEnum.SRL,ShiftCtrlEnum.SRA){
+          output(REGFILE_WRITE_DATA) := input(SHIFT_RIGHT)
+        }
+      }
+    }
+  }
+}
+
+class LightShifterPlugin extends Plugin[VexRiscv]{
+  object ShiftCtrlEnum extends SpinalEnum(binarySequential){
+    val DISABLE, SLL, SRL, SRA = newElement()
+  }
+
+  object SHIFT_CTRL extends Stageable(ShiftCtrlEnum())
+
+  override def setup(pipeline: VexRiscv): Unit = {
+    import Riscv._
+    import pipeline.config._
+    import IntAluPlugin._
+
+
+
+    val immediateActions = List[(Stageable[_ <: BaseType],Any)](
+      LEGAL_INSTRUCTION        -> True,
+      SRC1_CTRL                -> Src1CtrlEnum.RS,
+      SRC2_CTRL                -> Src2CtrlEnum.IMI,
+      ALU_CTRL                 -> AluCtrlEnum.SRC1,
+      REGFILE_WRITE_VALID      -> True,
+      BYPASSABLE_EXECUTE_STAGE -> True,
+      BYPASSABLE_MEMORY_STAGE  -> True,
+      REG1_USE                 -> True
+    )
+
+    val nonImmediateActions = List[(Stageable[_ <: BaseType],Any)](
+      LEGAL_INSTRUCTION        -> True,
+      SRC1_CTRL                -> Src1CtrlEnum.RS,
+      SRC2_CTRL                -> Src2CtrlEnum.RS,
+      ALU_CTRL                 -> AluCtrlEnum.SRC1,
+      REGFILE_WRITE_VALID      -> True,
+      BYPASSABLE_EXECUTE_STAGE -> True,
+      BYPASSABLE_MEMORY_STAGE  -> True,
+      REG1_USE                 -> True,
+      REG2_USE                 -> True
+    )
+
+    val decoderService = pipeline.service(classOf[DecoderService])
+    decoderService.addDefault(SHIFT_CTRL, ShiftCtrlEnum.DISABLE)
+    decoderService.add(List(
+      SLL  -> (nonImmediateActions ++ List(SHIFT_CTRL -> ShiftCtrlEnum.SLL)),
+      SRL  -> (nonImmediateActions ++ List(SHIFT_CTRL -> ShiftCtrlEnum.SRL)),
+      SRA  -> (nonImmediateActions ++ List(SHIFT_CTRL -> ShiftCtrlEnum.SRA))
+    ))
+
+    decoderService.add(List(
+      SLLI  -> (immediateActions ++ List(SHIFT_CTRL -> ShiftCtrlEnum.SLL)),
+      SRLI  -> (immediateActions ++ List(SHIFT_CTRL -> ShiftCtrlEnum.SRL)),
+      SRAI  -> (immediateActions ++ List(SHIFT_CTRL -> ShiftCtrlEnum.SRA))
+    ))
+  }
+
+  override def build(pipeline: VexRiscv): Unit = {
+    import pipeline._
+    import pipeline.config._
+
+
+    execute plug new Area{
+      import execute._
+
+      val isActive = RegInit(False)
+      val isShift = input(SHIFT_CTRL) =/= ShiftCtrlEnum.DISABLE
+      val amplitudeReg = Reg(UInt(5 bits))
+      val amplitude = isActive ? amplitudeReg | input(SRC2)(4 downto 0).asUInt
+      val shiftInput = isActive ? memory.input(REGFILE_WRITE_DATA) | input(SRC1)
+      val done = amplitude(4 downto 1) === 0
+
+
+      when(arbitration.isValid && isShift && input(SRC2)(4 downto 0) =/= 0){
+        insert(REGFILE_WRITE_DATA) := input(SHIFT_CTRL).mux(
+          ShiftCtrlEnum.SLL -> (shiftInput |<<  1),
+          default -> (((input(SHIFT_CTRL) === ShiftCtrlEnum.SRA && shiftInput.msb) ## shiftInput).asSInt >> 1).asBits  //ALU.SRL,ALU.SRA
+        )
+
+        when(!arbitration.isStuckByOthers){
+          isActive := True
+          amplitudeReg := amplitude - 1
+
+          when(done){
+            isActive := False
+          } otherwise{
+            arbitration.haltIt := True
+          }
+        }
+      }
+    }
+  }
+}

src/main/scala/SpinalRiscv/TopLevel.scala

@@ -37,7 +37,8 @@ object TopLevel {
         new RegFilePlugin(Plugin.SYNC),
         new IntAluPlugin,
         new SrcPlugin,
-        new FullBarrielShifterPlugin,
+//        new FullBarrielShifterPlugin,
+        new LightShifterPlugin,
         new DBusSimplePlugin,
         new HazardSimplePlugin(false, true, false, true),
         //        new HazardSimplePlugin(false, false, false, false),