diff options
Diffstat (limited to 'src/test')
| -rw-r--r-- | src/test/scala/firrtlTests/ConstantPropagationTests.scala | 25 |
1 files changed, 25 insertions, 0 deletions
diff --git a/src/test/scala/firrtlTests/ConstantPropagationTests.scala b/src/test/scala/firrtlTests/ConstantPropagationTests.scala index af186cda..ef52507f 100644 --- a/src/test/scala/firrtlTests/ConstantPropagationTests.scala +++ b/src/test/scala/firrtlTests/ConstantPropagationTests.scala @@ -1148,6 +1148,31 @@ class ConstantPropagationIntegrationSpec extends LowTransformSpec { execute(input, check, Seq.empty) } + "Const prop of registers" should "do limited speculative expansion of optimized muxes to absorb bigger cones" in { + val input = + """circuit Top : + | module Top : + | input clock : Clock + | input en : UInt<1> + | output out : UInt<1> + | reg r1 : UInt<1>, clock + | reg r2 : UInt<1>, clock + | when en : + | r1 <= UInt<1>(1) + | r2 <= UInt<1>(0) + | when en : + | r2 <= r2 + | out <= xor(r1, r2)""".stripMargin + val check = + """circuit Top : + | module Top : + | input clock : Clock + | input en : UInt<1> + | output out : UInt<1> + | out <= UInt<1>("h1")""".stripMargin + execute(input, check, Seq.empty) + } + "A register with constant reset and all connection to either itself or the same constant" should "be replaced with that constant" in { val input = """circuit Top : |