Merge pull request #1384 from freechipsproject/no-more-compile-internal

No more compile internal

1 files changed, 47 insertions, 0 deletions

diff --git a/core/src/main/scala/chisel3/UIntFactory.scala b/core/src/main/scala/chisel3/UIntFactory.scala
new file mode 100644
index 00000000..3868962b
--- /dev/null
+++ b/core/src/main/scala/chisel3/UIntFactory.scala
@@ -0,0 +1,47 @@
+// See LICENSE for license details.
+
+package chisel3
+
+import chisel3.internal.firrtl.{IntervalRange, KnownWidth, ULit, UnknownWidth, Width}
+import firrtl.Utils
+import firrtl.constraint.IsKnown
+import firrtl.ir.{Closed, IntWidth, Open}
+
+// This is currently a factory because both Bits and UInt inherit it.
+trait UIntFactory {
+  /** Create a UInt type with inferred width. */
+  def apply(): UInt = apply(Width())
+  /** Create a UInt port with specified width. */
+  def apply(width: Width): UInt = new UInt(width)
+
+  /** Create a UInt literal with specified width. */
+  // scalastyle:off method.name
+  protected[chisel3] def Lit(value: BigInt, width: Width): UInt = {
+    val lit = ULit(value, width)
+    val result = new UInt(lit.width)
+    // Bind result to being an Literal
+    lit.bindLitArg(result)
+  }
+  /** Create a UInt with the specified range, validate that range is effectively > 0
+    */
+  //scalastyle:off cyclomatic.complexity
+  def apply(range: IntervalRange): UInt = {
+    // Check is only done against lower bound because range will already insist that range high >= low
+    range.lowerBound match {
+      case Closed(bound) if bound < 0 =>
+        throw new ChiselException(s"Attempt to create UInt with closed lower bound of $bound, must be > 0")
+      case Open(bound) if bound < -1 =>
+        throw new ChiselException(s"Attempt to create UInt with open lower bound of $bound, must be > -1")
+      case _ =>
+    }
+
+    // because this is a UInt we don't have to take into account the lower bound
+    val newWidth = if(range.upperBound.isInstanceOf[IsKnown]) {
+      KnownWidth(Utils.getUIntWidth(range.maxAdjusted.get).max(1))  // max(1) handles range"[0,0]"
+    } else {
+      UnknownWidth()
+    }
+
+    apply(newWidth)
+  }
+}