Add abs_and_normal_FAC1

src/basic/math/b8d2.abs_and_normal.s

@@ -0,0 +1,22 @@
+;; #LAYOUT# STD *       #TAKE
+;; #LAYOUT# X16 BASIC_0 #TAKE-OFFSET 2000
+;; #LAYOUT# *   BASIC_0 #TAKE
+;; #LAYOUT# *   *       #IGNORE
+
+; This file is under the MIT license, it contains code released by Microsoft Corporation.
+; See LICENSE for more information.
+
+; Math package - abs and noramlize FAC1
+;
+; Input:
+; CF - Sign of number
+;
+; This is verified to be identical to the original Microsoft implementation where it was named FADFLT.
+;
+
+abs_and_normal_FAC1:
+
+    bcs normal_FAC1             ; If CF set only normalize
+    jsr inv_FAC1
+    
+    ; Fallthrough to normal_FAC1