Deprecate implicit .U() and .S() syntax for literal bit extracts (backport #2534) (#2559)

* Deprecate .U() and .S() syntax for literal bit extracts (#2534)

(cherry picked from commit cadaf33a650ef898fdab2f81244e4ad6a07a9ea8)

# Conflicts:
#	macros/src/main/scala/chisel3/internal/sourceinfo/SourceInfoTransform.scala

* Fix backport conflict (#2560)

Co-authored-by: Jared Barocsi <82000041+jared-barocsi@users.noreply.github.com>

1 files changed, 28 insertions, 0 deletions

diff --git a/macros/src/main/scala/chisel3/internal/sourceinfo/SourceInfoTransform.scala b/macros/src/main/scala/chisel3/internal/sourceinfo/SourceInfoTransform.scala
index 3e310774..6c83da00 100644
--- a/macros/src/main/scala/chisel3/internal/sourceinfo/SourceInfoTransform.scala
+++ b/macros/src/main/scala/chisel3/internal/sourceinfo/SourceInfoTransform.scala
@@ -249,3 +249,31 @@ class SourceInfoWhiteboxTransform(val c: whitebox.Context) extends AutoSourceTra
     q"$thisObj.$doFuncTerm($that)($implicitSourceInfo, $implicitCompileOptions)"
   }
 }
+
+// Workaround for https://github.com/sbt/sbt/issues/3966
+object IntLiteralApplyTransform
+
+class IntLiteralApplyTransform(val c: Context) extends AutoSourceTransform {
+  import c.universe._
+
+  def safeApply(x: c.Tree): c.Tree = {
+    c.macroApplication match {
+      case q"$_.$clazz($lit).$func.apply($arg)" =>
+        if (
+          Set("U", "S").contains(func.toString) &&
+          Set("fromStringToLiteral", "fromIntToLiteral", "fromLongToIteral", "fromBigIntToLiteral").contains(
+            clazz.toString
+          )
+        ) {
+          val msg =
+            s"""Passing an Int to .$func is usually a mistake: It does *not* set the width but does a bit extract.
+               |Did you mean .$func($arg.W)?
+               |If you want to hide this message, assign .$func to a val first, then invoke .apply($arg)
+               |""".stripMargin
+          c.warning(c.enclosingPosition, msg)
+        }
+      case _ => // do nothing
+    }
+    q"$thisObj.$doFuncTerm($x)($implicitSourceInfo, $implicitCompileOptions)"
+  }
+}