Make bitwiseNot an extern

Author: marzipankaiser

libraries/common/binstream.effekt

@@ -254,14 +254,6 @@ def collectBitsBE{ body: => Unit / emit[Bit] }: Int = {
   res
 }
 
-/// bitwise not on integers
-def bitwiseNot(n: Int): Int = {
-  // TODO currently implemented in Effekt, should use extern ?
-  collectBitsBE{
-    try bitsBE(n) with emit[Bit]{ b => resume(do emit(not(b))) }
-  }
-}
-
 /// split emitted bytes and emit the individual bits in big-endian bit order
 def ungroupBytes{ body: => Unit / emit[Byte] }: Unit / emit[Bit] =
   for[Byte]{body}{ b => bits(b) }

libraries/common/effekt.effekt

@@ -665,6 +665,12 @@ extern pure def bitwiseXor(x: Int, y: Int): Int =
   llvm "%z = xor %Int ${x}, ${y} ret %Int %z"
   vm "effekt::bitwiseXor(Int, Int)"
 
+extern pure def bitwiseNot(x: Int): Int =
+  js "(~${x})"
+  chez "(lognot ${x})"
+  llvm "%z = xor %Int ${x}, -1 ret %Int %z"
+  vm "effekt::bitwiseNot(Int)"
+
 
 // Byte operations
 // ===============