MIG optimization

[ratul619]

Hi , i generated a blif using yosys for full adder. And when i try to use lsoracle for optimization , doesnt seem to give optimized result. For example , i expect the cout to be just one level - majority between In1 , In2 & Cin.

.model fullAdder .inputs In1 In2 Cin .outputs Sum Cout .names $false .names $true 1 .names $undef .names In1 In2 $xor$fa.v:25$1_Y 10 1 01 1 .names $xor$fa.v:25$1_Y Cin Sum 10 1 01 1 .names In1 In2 $and$fa.v:27$3_Y 11 1 .names In2 Cin $and$fa.v:27$4_Y 11 1 .names $and$fa.v:27$3_Y $and$fa.v:27$4_Y $or$fa.v:27$5_Y 1- 1 -1 1 .names Cin In1 $and$fa.v:27$6_Y 11 1 .names $or$fa.v:27$5_Y $and$fa.v:27$6_Y Cout 1- 1 -1 1 .end

Commands used :

read_blif -m fa.blif migtune migscript

MIG logic depth 5 nodes 13 MIG logic depth 5 nodes 13 Final ntk size = 13 and depth = 5 Area Delay Product = 65 Full Optimization: 6ms Finished optimization

Any more optimization step i am missing ?? Thanks

[ratul619]

??

[yashton]

In general, the logic synthesis operations being performed attempt to apply large scale transformations to the logic graph in an attempt to optimize. For something like a single gate or a very small number of gates, these operations don't have a lot of impact and will usually make things significantly worse.