Adding binary encoded 2:1 vectorized mux

- More efficient than one hot when it's not possible for synthesis to do global optimization.

Author: aolofsson

lambdalib/veclib/__init__.py

@@ -2,6 +2,7 @@
 from .la_vinv.la_vinv import Vinv
 from .la_vmux.la_vmux import Vmux
 from .la_vmux2.la_vmux2 import Vmux2
+from .la_vmux2.la_vmux2b import Vmux2b
 from .la_vmux3.la_vmux3 import Vmux3
 from .la_vmux4.la_vmux4 import Vmux4
 from .la_vmux5.la_vmux5 import Vmux5
@@ -13,6 +14,7 @@
            'Vinv',
            'Vmux',
            'Vmux2',
+           'Vmux2b',
            'Vmux3',
            'Vmux4',
            'Vmux5',

lambdalib/veclib/la_vmux2b/la_vmux2b.py

@@ -0,0 +1,13 @@
+from lambdalib import Lambda
+
+
+class Vmux2b(Lambda):
+    def __init__(self):
+        name = 'la_vmux2'
+        sources = [f'rtl/{name}.v']
+        super().__init__(name, sources, __file__)
+
+
+if __name__ == "__main__":
+    d = Vmux2b()
+    d.write_fileset(f"{d.name()}.f", fileset="rtl")

lambdalib/veclib/la_vmux2b/rtl/la_vmux2b.v

@@ -0,0 +1,20 @@
+//############################################################################
+//# Function: 2-Input one-hot vectorized mux                                 #
+//# Copyright: Lambda Project Authors. All rights Reserved.                  #
+//# License:  MIT (see LICENSE file in Lambda repository)                    #
+//############################################################################
+
+module la_vmux2 #(parameter W = 1,           // width of mux
+                  parameter PROP = "DEFAULT" // cell property
+                  )
+   (
+    input          sel,
+    input [W-1:0]  in1,
+    input [W-1:0]  in0,
+    output [W-1:0] out
+    );
+
+   assign out[W-1:0] = ({(W) {~sel}} & in0[W-1:0] |
+                        {(W) {sel}}  & in1[W-1:0]);
+
+endmodule