Merge branch '3.5.x' into 3.5-release

10 files changed, 298 insertions, 18 deletions

diff --git a/src/main/scala/chisel3/util/BlackBoxUtils.scala b/src/main/scala/chisel3/util/BlackBoxUtils.scala
index 7c4400f8..579a6307 100644
--- a/src/main/scala/chisel3/util/BlackBoxUtils.scala
+++ b/src/main/scala/chisel3/util/BlackBoxUtils.scala
@@ -4,13 +4,7 @@ package chisel3.util
 
 import chisel3._
 import chisel3.experimental.{ChiselAnnotation, RunFirrtlTransform}
-import firrtl.transforms.{
-  BlackBoxInlineAnno,
-  BlackBoxNotFoundException,
-  BlackBoxPathAnno,
-  BlackBoxResourceAnno,
-  BlackBoxSourceHelper
-}
+import firrtl.transforms.{BlackBoxInlineAnno, BlackBoxNotFoundException, BlackBoxPathAnno, BlackBoxSourceHelper}
 import firrtl.annotations.ModuleName
 import logger.LazyLogging
 
diff --git a/src/main/scala/chisel3/util/ExtModuleUtils.scala b/src/main/scala/chisel3/util/ExtModuleUtils.scala
index 5c9c02ba..8a687d36 100644
--- a/src/main/scala/chisel3/util/ExtModuleUtils.scala
+++ b/src/main/scala/chisel3/util/ExtModuleUtils.scala
@@ -3,13 +3,7 @@
 package chisel3.util
 
 import chisel3.experimental.{ChiselAnnotation, ExtModule, RunFirrtlTransform}
-import firrtl.transforms.{
-  BlackBoxInlineAnno,
-  BlackBoxNotFoundException,
-  BlackBoxPathAnno,
-  BlackBoxResourceAnno,
-  BlackBoxSourceHelper
-}
+import firrtl.transforms.{BlackBoxInlineAnno, BlackBoxNotFoundException, BlackBoxPathAnno, BlackBoxSourceHelper}
 
 import BlackBoxHelpers._
 
diff --git a/src/test/scala/chiselTests/BlackBox.scala b/src/test/scala/chiselTests/BlackBox.scala
index 27cdbbc4..f923a94a 100644
--- a/src/test/scala/chiselTests/BlackBox.scala
+++ b/src/test/scala/chiselTests/BlackBox.scala
@@ -145,6 +145,17 @@ class BlackBoxTypeParam(w: Int, raw: String) extends BlackBox(Map("T" -> RawPara
   })
 }
 
+class BlackBoxNoIO extends BlackBox {
+  // Whoops! typo
+  val ioo = IO(new Bundle {
+    val out = Output(UInt(8.W))
+  })
+}
+
+class BlackBoxUIntIO extends BlackBox {
+  val io = IO(Output(UInt(8.W)))
+}
+
 class BlackBoxWithParamsTester extends BasicTester {
   val blackBoxOne = Module(new BlackBoxConstant(1))
   val blackBoxFour = Module(new BlackBoxConstant(4))
@@ -192,7 +203,23 @@ class BlackBoxSpec extends ChiselFlatSpec {
       assert(DataMirror.modulePorts(m) == Seq("in" -> m.io.in, "out" -> m.io.out))
     })
   }
-  "A BlackBoxed using suggestName(\"io\")" should "work (but don't do this)" in {
+  "A BlackBox using suggestName(\"io\")" should "work (but don't do this)" in {
     assertTesterPasses({ new BlackBoxTesterSuggestName }, Seq("/chisel3/BlackBoxTest.v"), TesterDriver.verilatorOnly)
   }
+
+  "A BlackBox with no 'val io'" should "give a reasonable error message" in {
+    (the[ChiselException] thrownBy {
+      ChiselStage.elaborate(new Module {
+        val inst = Module(new BlackBoxNoIO)
+      })
+    }).getMessage should include("must have a port named 'io' of type Record")
+  }
+
+  "A BlackBox with non-Record 'val io'" should "give a reasonable error message" in {
+    (the[ChiselException] thrownBy {
+      ChiselStage.elaborate(new Module {
+        val inst = Module(new BlackBoxUIntIO)
+      })
+    }).getMessage should include("must have a port named 'io' of type Record")
+  }
 }
diff --git a/src/test/scala/chiselTests/BulkConnectSpec.scala b/src/test/scala/chiselTests/BulkConnectSpec.scala
index 463122bd..281890d4 100644
--- a/src/test/scala/chiselTests/BulkConnectSpec.scala
+++ b/src/test/scala/chiselTests/BulkConnectSpec.scala
@@ -94,6 +94,26 @@ class BulkConnectSpec extends ChiselPropSpec {
     chirrtl should include("deq <= enq")
   }
 
+  property("Chisel connects should not emit a FIRRTL bulk connect for BlackBox IO Bundles") {
+    class MyBundle extends Bundle {
+      val O: Bool = Output(Bool())
+      val I: Bool = Input(Bool())
+    }
+
+    val chirrtl = ChiselStage.emitChirrtl(new Module {
+      val io: MyBundle = IO(Flipped(new MyBundle))
+
+      val bb = Module(new BlackBox {
+        val io: MyBundle = IO(Flipped(new MyBundle))
+      })
+
+      io <> bb.io
+    })
+    // There won't be a bb.io Bundle in FIRRTL, so connections have to be done element-wise
+    chirrtl should include("bb.O <= io.O")
+    chirrtl should include("io.I <= bb.I")
+  }
+
   property("MonoConnect should bulk connect undirectioned internal wires") {
     val chirrtl = ChiselStage.emitChirrtl(new Module {
       val io = IO(new Bundle {})
diff --git a/src/test/scala/chiselTests/InvalidateAPISpec.scala b/src/test/scala/chiselTests/InvalidateAPISpec.scala
index 2c51e5d2..dbd353a0 100644
--- a/src/test/scala/chiselTests/InvalidateAPISpec.scala
+++ b/src/test/scala/chiselTests/InvalidateAPISpec.scala
@@ -228,4 +228,12 @@ class InvalidateAPISpec extends ChiselPropSpec with Matchers with BackendCompila
     val firrtlOutput = myGenerateFirrtl(new ModuleWithoutDontCare)
     firrtlOutput should include("is invalid")
   }
+
+  property("a clock should be able to be connected to a DontCare") {
+    class ClockConnectedToDontCare extends Module {
+      val foo = IO(Output(Clock()))
+      foo := DontCare
+    }
+    myGenerateFirrtl(new ClockConnectedToDontCare) should include("foo is invalid")
+  }
 }
diff --git a/src/test/scala/chiselTests/Mem.scala b/src/test/scala/chiselTests/Mem.scala
index 4dcb1ad4..c5fcc6b1 100644
--- a/src/test/scala/chiselTests/Mem.scala
+++ b/src/test/scala/chiselTests/Mem.scala
@@ -3,6 +3,7 @@
 package chiselTests
 
 import chisel3._
+import chisel3.stage.ChiselStage
 import chisel3.util._
 import chisel3.testers.BasicTester
 
@@ -141,6 +142,52 @@ class MemBundleTester extends BasicTester {
   }
 }
 
+private class TrueDualPortMemoryIO(val addrW: Int, val dataW: Int) extends Bundle {
+  require(addrW > 0, "address width must be greater than 0")
+  require(dataW > 0, "data width must be greater than 0")
+
+  val clka = Input(Clock())
+  val ena = Input(Bool())
+  val wea = Input(Bool())
+  val addra = Input(UInt(addrW.W))
+  val dia = Input(UInt(dataW.W))
+  val doa = Output(UInt(dataW.W))
+
+  val clkb = Input(Clock())
+  val enb = Input(Bool())
+  val web = Input(Bool())
+  val addrb = Input(UInt(addrW.W))
+  val dib = Input(UInt(dataW.W))
+  val dob = Output(UInt(dataW.W))
+}
+
+private class TrueDualPortMemory(addrW: Int, dataW: Int) extends RawModule {
+  val io = IO(new TrueDualPortMemoryIO(addrW, dataW))
+  val ram = SyncReadMem(1 << addrW, UInt(dataW.W))
+
+  // Port a
+  withClock(io.clka) {
+    io.doa := DontCare
+    when(io.ena) {
+      when(io.wea) {
+        ram(io.addra) := io.dia
+      }
+      io.doa := ram(io.addra)
+    }
+  }
+
+  // Port b
+  withClock(io.clkb) {
+    io.dob := DontCare
+    when(io.enb) {
+      when(io.web) {
+        ram(io.addrb) := io.dib
+      }
+      io.dob := ram(io.addrb)
+    }
+  }
+}
+
 class MemorySpec extends ChiselPropSpec {
   property("Mem of Vec should work") {
     assertTesterPasses { new MemVecTester }
@@ -186,4 +233,9 @@ class MemorySpec extends ChiselPropSpec {
       |}
       |""".stripMargin should compile
   }
+
+  property("memories in modules without implicit clock should compile without warning or error") {
+    val stage = new ChiselStage
+    stage.emitVerilog(new TrueDualPortMemory(4, 32))
+  }
 }
diff --git a/src/test/scala/chiselTests/ReduceTreeSpec.scala b/src/test/scala/chiselTests/ReduceTreeSpec.scala
new file mode 100644
index 00000000..3f078106
--- /dev/null
+++ b/src/test/scala/chiselTests/ReduceTreeSpec.scala
@@ -0,0 +1,106 @@
+// SPDX-License-Identifier: Apache-2.0
+
+package chiselTests
+
+import chisel3._
+import chisel3.util._
+import chisel3.testers.BasicTester
+
+class Arbiter[T <: Data: Manifest](n: Int, private val gen: T) extends Module {
+  val io = IO(new Bundle {
+    val in = Flipped(Vec(n, new DecoupledIO(gen)))
+    val out = new DecoupledIO(gen)
+  })
+
+  def arbitrateTwo(a: DecoupledIO[T], b: DecoupledIO[T]) = {
+
+    val idleA :: idleB :: hasA :: hasB :: Nil = Enum(4)
+    val regData = Reg(gen)
+    val regState = RegInit(idleA)
+    val out = Wire(new DecoupledIO(gen))
+
+    a.ready := regState === idleA
+    b.ready := regState === idleB
+    out.valid := (regState === hasA || regState === hasB)
+
+    switch(regState) {
+      is(idleA) {
+        when(a.valid) {
+          regData := a.bits
+          regState := hasA
+        }.otherwise {
+          regState := idleB
+        }
+      }
+      is(idleB) {
+        when(b.valid) {
+          regData := b.bits
+          regState := hasB
+        }.otherwise {
+          regState := idleA
+        }
+      }
+      is(hasA) {
+        when(out.ready) {
+          regState := idleB
+        }
+      }
+      is(hasB) {
+        when(out.ready) {
+          regState := idleA
+        }
+      }
+    }
+
+    out.bits := regData.asUInt + 1.U
+    out
+  }
+
+  io.out <> io.in.reduceTree(arbitrateTwo)
+}
+
+class ReduceTreeBalancedTester(nodes: Int) extends BasicTester {
+
+  val cnt = RegInit(0.U(8.W))
+  val min = RegInit(99.U(8.W))
+  val max = RegInit(0.U(8.W))
+
+  val dut = Module(new Arbiter(nodes, UInt(16.W)))
+  for (i <- 0 until nodes) {
+    dut.io.in(i).valid := true.B
+    dut.io.in(i).bits := 0.U
+  }
+  dut.io.out.ready := true.B
+
+  when(dut.io.out.valid) {
+    val hops = dut.io.out.bits
+    when(hops < min) {
+      min := hops
+    }
+    when(hops > max) {
+      max := hops
+    }
+  }
+
+  when(!(max === 0.U || min === 99.U)) {
+    assert(max - min <= 1.U)
+  }
+
+  cnt := cnt + 1.U
+  when(cnt === 10.U) {
+    stop()
+  }
+}
+
+class ReduceTreeBalancedSpec extends ChiselPropSpec {
+  property("Tree shall be fair and shall have a maximum difference of one hop for each node") {
+
+    // This test will fail for 5 nodes due to an unbalanced tree.
+    // A fix is on the way.
+    for (n <- 1 to 5) {
+      assertTesterPasses {
+        new ReduceTreeBalancedTester(n)
+      }
+    }
+  }
+}
diff --git a/src/test/scala/chiselTests/experimental/DataView.scala b/src/test/scala/chiselTests/experimental/DataView.scala
index 0285a524..e7caacfd 100644
--- a/src/test/scala/chiselTests/experimental/DataView.scala
+++ b/src/test/scala/chiselTests/experimental/DataView.scala
@@ -332,6 +332,36 @@ class DataViewSpec extends ChiselFlatSpec {
     chirrtl should include("dataOut <= vec[addr]")
   }
 
+  it should "support dynamic indexing for Vecs that correspond 1:1 in a view" in {
+    class MyBundle extends Bundle {
+      val foo = Vec(4, UInt(8.W))
+      val bar = UInt(2.W)
+    }
+    implicit val myView = DataView[(Vec[UInt], UInt), MyBundle](
+      _ => new MyBundle,
+      _._1 -> _.foo,
+      _._2 -> _.bar
+    )
+    class MyModule extends Module {
+      val dataIn = IO(Input(UInt(8.W)))
+      val addr = IO(Input(UInt(2.W)))
+      val dataOut = IO(Output(UInt(8.W)))
+
+      val vec = RegInit(0.U.asTypeOf(Vec(4, UInt(8.W))))
+      val addrReg = Reg(UInt(2.W))
+      val view = (vec, addrReg).viewAs[MyBundle]
+      // Dynamic indexing is more of a "generator" in Chisel3 than an individual node
+      // This style is not recommended, this is just testing the behavior
+      val selected = view.foo(view.bar)
+      view.bar := addr
+      selected := dataIn
+      dataOut := selected
+    }
+    val chirrtl = ChiselStage.emitChirrtl(new MyModule)
+    chirrtl should include("vec[addrReg] <= dataIn")
+    chirrtl should include("dataOut <= vec[addrReg]")
+  }
+
   it should "error if you try to dynamically index a Vec view that does not correspond to a Vec target" in {
     class MyModule extends Module {
       val inA, inB = IO(Input(UInt(8.W)))
diff --git a/src/test/scala/chiselTests/experimental/DataViewTargetSpec.scala b/src/test/scala/chiselTests/experimental/DataViewTargetSpec.scala
index da27c9c8..ddeeab6e 100644
--- a/src/test/scala/chiselTests/experimental/DataViewTargetSpec.scala
+++ b/src/test/scala/chiselTests/experimental/DataViewTargetSpec.scala
@@ -125,9 +125,7 @@ class DataViewTargetSpec extends ChiselFlatSpec {
     val pairs = annos.collect { case DummyAnno(t, idx) => (idx, t.toString) }.sortBy(_._1)
     val expected = Seq(
       0 -> "~MyParent|MyChild>out.foo",
-      // The child of the view that was itself an Aggregate got split because 1:1 is lacking here
-      1 -> "~MyParent|MyChild>out.foo[0]",
-      1 -> "~MyParent|MyChild>out.foo[1]",
+      1 -> "~MyParent|MyChild>out.foo",
       2 -> "~MyParent|MyParent/inst:MyChild>out.foo",
       3 -> "~MyParent|MyParent/inst:MyChild>out"
     )
diff --git a/src/test/scala/chiselTests/experimental/FlatIOSpec.scala b/src/test/scala/chiselTests/experimental/FlatIOSpec.scala
new file mode 100644
index 00000000..dfce447f
--- /dev/null
+++ b/src/test/scala/chiselTests/experimental/FlatIOSpec.scala
@@ -0,0 +1,51 @@
+// SPDX-License-Identifier: Apache-2.0
+
+package chiselTests.experimental
+
+import chisel3._
+import chisel3.util.Valid
+import chisel3.stage.ChiselStage.emitChirrtl
+import chisel3.experimental.FlatIO
+import chiselTests.ChiselFlatSpec
+
+class FlatIOSpec extends ChiselFlatSpec {
+  behavior.of("FlatIO")
+
+  it should "create ports without a prefix" in {
+    class MyModule extends RawModule {
+      val io = FlatIO(new Bundle {
+        val in = Input(UInt(8.W))
+        val out = Output(UInt(8.W))
+      })
+      io.out := io.in
+    }
+    val chirrtl = emitChirrtl(new MyModule)
+    chirrtl should include("input in : UInt<8>")
+    chirrtl should include("output out : UInt<8>")
+    chirrtl should include("out <= in")
+  }
+
+  it should "support bulk connections between FlatIOs and regular IOs" in {
+    class MyModule extends RawModule {
+      val in = FlatIO(Input(Valid(UInt(8.W))))
+      val out = IO(Output(Valid(UInt(8.W))))
+      out := in
+    }
+    val chirrtl = emitChirrtl(new MyModule)
+    chirrtl should include("out.bits <= bits")
+    chirrtl should include("out.valid <= valid")
+  }
+
+  it should "dynamically indexing Vecs inside of FlatIOs" in {
+    class MyModule extends RawModule {
+      val io = FlatIO(new Bundle {
+        val addr = Input(UInt(2.W))
+        val in = Input(Vec(4, UInt(8.W)))
+        val out = Output(Vec(4, UInt(8.W)))
+      })
+      io.out(io.addr) := io.in(io.addr)
+    }
+    val chirrtl = emitChirrtl(new MyModule)
+    chirrtl should include("out[addr] <= in[addr]")
+  }
+}