Added disalowIOCreation as a public API

chipsalliance · Oct 13, 2023 · fe5891a · fe5891a
1 parent 7acd8c3
commit fe5891a
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Showing 3 changed files with 23 additions and 5 deletions.
diff --git a/core/src/main/scala/chisel3/IO.scala b/core/src/main/scala/chisel3/IO.scala
@@ -23,7 +23,8 @@ object IO {
     */
   def apply[T <: Data](iodef: => T)(implicit sourceInfo: SourceInfo): T = {
     val module = Module.currentModule.get // Impossible to fail
-    require(module.isIOCreationAllowed, "This module cannot have user-created IO")
+    if (!module.isIOCreationAllowed)
+      Builder.error("This module cannot have IOs instantiated after calling disallowIOCreation()")
     require(!module.isClosed, "Can't add more ports after module close")
     val prevId = Builder.idGen.value
     val data = iodef // evaluate once (passed by name)

diff --git a/core/src/main/scala/chisel3/Module.scala b/core/src/main/scala/chisel3/Module.scala
@@ -403,7 +403,7 @@ package experimental {
     private[chisel3] def isIOCreationAllowed = _isIOCreationAllowed
 
     /** Disallow any more IO creation for this module. */
-    private[chisel3] def disallowIOCreation(): Unit = {
+    def disallowIOCreation(): Unit = {
       _isIOCreationAllowed = false
     }
 

diff --git a/src/test/scala/chiselTests/FixedIOModuleSpec.scala b/src/test/scala/chiselTests/FixedIOModuleSpec.scala
@@ -20,10 +20,10 @@ class FixedIOModuleSpec extends ChiselFlatSpec with Utils with MatchesAndOmits {
     class Foo extends FixedIORawModule[Bool](Bool()) {
       val a = IO(Bool())
     }
-    val exception = intercept[IllegalArgumentException] {
-      ChiselStage.emitCHIRRTL(new Foo)
+    val exception = intercept[ChiselException] {
+      ChiselStage.emitCHIRRTL(new Foo, Array("--throw-on-first-error"))
     }
-    exception.getMessage should include("This module cannot have user-created IO")
+    exception.getMessage should include("This module cannot have IOs instantiated after calling disallowIOCreation()")
   }
 
   "FixedIOBlackBox" should "create a module with flattend IO" in {
@@ -47,4 +47,21 @@ class FixedIOModuleSpec extends ChiselFlatSpec with Utils with MatchesAndOmits {
     )()
   }
 
+  "User defined RawModules" should "be able to lock down their ios" in {
+
+    class Bar extends RawModule {
+      val in = IO(Input(UInt(1.W)))
+      val out = IO(Output(UInt(1.W)))
+
+      disallowIOCreation()
+
+      val other = IO(Input(UInt(1.W)))
+    }
+
+    val exception = intercept[ChiselException] {
+      ChiselStage.emitCHIRRTL(new Bar, Array("--throw-on-first-error"))
+    }
+    exception.getMessage should include("This module cannot have IOs instantiated after calling disallowIOCreation()")
+  }
+
 }