Update negative literal emission (#1782)

* test const prop of addition of negative literals

* Emitter: handle minimum negative values correctly

* update expected verilog in AsyncResetSpec

2 files changed, 11 insertions, 1 deletions

diff --git a/src/test/scala/firrtlTests/AsyncResetSpec.scala b/src/test/scala/firrtlTests/AsyncResetSpec.scala
index 29c09787..65c68b27 100644
--- a/src/test/scala/firrtlTests/AsyncResetSpec.scala
+++ b/src/test/scala/firrtlTests/AsyncResetSpec.scala
@@ -278,7 +278,7 @@ class AsyncResetSpec extends FirrtlFlatSpec {
         |z <= r""".stripMargin
       )
     fixedResult should containLine ("always @(posedge clock or posedge reset) begin")
-    fixedResult should containLine ("r <= -2'sh2;")
+    fixedResult should containLine ("r <= 2'sh2;")
 
     val intervalResult = compileBody(s"""
         |input clock : Clock
diff --git a/src/test/scala/firrtlTests/ConstantPropagationTests.scala b/src/test/scala/firrtlTests/ConstantPropagationTests.scala
index 32303949..131f9466 100644
--- a/src/test/scala/firrtlTests/ConstantPropagationTests.scala
+++ b/src/test/scala/firrtlTests/ConstantPropagationTests.scala
@@ -1604,4 +1604,14 @@ class ConstantPropagationEquivalenceSpec extends FirrtlFlatSpec {
          |    out <= head_temp""".stripMargin
     firrtlEquivalenceTest(input, transforms)
   }
+
+   "addition of negative literals" should "be propagated" in {
+     val input =
+       s"""circuit AddTester :
+          |  module AddTester :
+          |    output ref : SInt<2>
+          |    ref <= add(SInt<1>("h-1"), SInt<1>("h-1"))
+          |""".stripMargin
+     firrtlEquivalenceTest(input, transforms)
+   }
 }