Warn on <literal>.asUInt|.asSInt(_: Int) (#4764)

The user probably forgot .W. Apply the same technique as used for .U|.S.

Author: jackkoenig

core/src/main/scala/chisel3/package.scala

@@ -30,10 +30,6 @@ package object chisel3 {
     * after this call using apply, ie. 0.asUInt(1)(0) due to potential for
     * confusion (the 1 is a bit length and the 0 is a bit extraction position).
     * Prefer storing the result and then extracting from it.
-    *
-    * Implementation note: the empty parameter list (like `U()`) is necessary to prevent
-    * interpreting calls that have a non-Width parameter as a chained apply, otherwise things like
-    * `0.asUInt(16)` (instead of `16.W`) compile without error and produce undesired results.
     */
   implicit class fromBigIntToLiteral(bigint: BigInt) {
 

macros/src/main/scala/chisel3/internal/sourceinfo/SourceInfoTransform.scala

@@ -361,13 +361,13 @@ class IntLiteralApplyTransform(val c: Context) extends AutoSourceTransform {
     c.macroApplication match {
       case q"$_.$clazz($lit).$func.apply($arg)" =>
         if (
-          Set("U", "S").contains(func.toString) &&
+          Set("U", "S", "asUInt", "asSInt").contains(func.toString) &&
           Set("fromStringToLiteral", "fromIntToLiteral", "fromLongToIteral", "fromBigIntToLiteral").contains(
             clazz.toString
           )
         ) {
           val msg =
-            s"""Passing an Int to .$func is usually a mistake: It does *not* set the width but does a bit extract.
+            s"""Passing an Int to .$func is usually a mistake: It does *not* set the width; it does a bit extraction.
                |Did you mean .$func($arg.W)?
                |If you do want bit extraction, use .$func.extract($arg) instead.
                |""".stripMargin