This adds a mechanism for the unittests to be run with the TreadleBackend

This mechanism is not enabled and should not change the behavior of existing tests
A following PR will deliver a switch that will allow changing the backend.
The reasons for this PR
- Treadle tests run much faster, enabling quicker debugging and CI cycles
- This will help ensure fidelity of Treadle to the Verilator backend

A few tests are marked as verilator only due to black box limitations

Change treadle to a direct dependency

I tried to make it a test only dependency but the TesterDriver sits in src/main requiring that
regular compile have access to treadle

Oops, made treadle the default

A number of changes in response to @ducky64 review
- made backend check clearer and add error handling for multiple backends specified
- Fixed duplicate TargetDirAnnotation uses in Treadle backend
- Cleaned up BlackBox test formatting
- Undid unnecessary debugging changes from Counter
- Undid .gitignore change, that should be on another PR

A number of changes in response to @ducky64 review
- Undid debugging changes made to BitWiseOps

1 files changed, 5 insertions, 3 deletions

diff --git a/src/test/scala/chiselTests/aop/InjectionSpec.scala b/src/test/scala/chiselTests/aop/InjectionSpec.scala
index 6c022d60..7e09bd54 100644
--- a/src/test/scala/chiselTests/aop/InjectionSpec.scala
+++ b/src/test/scala/chiselTests/aop/InjectionSpec.scala
@@ -2,7 +2,7 @@
 
 package chiselTests.aop
 
-import chisel3.testers.BasicTester
+import chisel3.testers.{BasicTester, TesterDriver}
 import chiselTests.ChiselFlatSpec
 import chisel3._
 import chisel3.aop.injecting.InjectingAspect
@@ -47,10 +47,12 @@ class InjectionSpec extends ChiselFlatSpec {
     assertTesterFails{ new AspectTester(Seq(9, 9, 9)) }
   }
   "Test" should "pass if pass wrong values, but correct with aspect" in {
-    assertTesterPasses({ new AspectTester(Seq(9, 9, 9))} , Nil, Seq(correctValueAspect))
+    assertTesterPasses({ new AspectTester(Seq(9, 9, 9))} , Nil, Seq(correctValueAspect) ++ TesterDriver.verilatorOnly)
   }
   "Test" should "pass if pass wrong values, then wrong aspect, then correct aspect" in {
-    assertTesterPasses({ new AspectTester(Seq(9, 9, 9))} , Nil, Seq(wrongValueAspect, correctValueAspect))
+    assertTesterPasses(
+      new AspectTester(Seq(9, 9, 9)), Nil, Seq(wrongValueAspect, correctValueAspect) ++ TesterDriver.verilatorOnly
+    )
   }
   "Test" should "fail if pass wrong values, then correct aspect, then wrong aspect" in {
     assertTesterFails({ new AspectTester(Seq(9, 9, 9))} , Nil, Seq(correctValueAspect, wrongValueAspect))