# From https://github.com/cliffordwolf/icestorm/blob/be0bca0/icefuzz/timings_hx8k.txt

# NB: Inputs/Outputs must be ordered alphabetically
#     (with exceptions for carry in/out)

# Inputs: I0 I1 CI
# Outputs: CO
#   (NB: carry chain input/output must be last
#        input/output and have been moved there
#        overriding the alphabetical ordering)
SB_CARRY 1 1 3 1
259 231 126

# Inputs: I0 I1 I2 I3
# Outputs: O
SB_LUT4 2 1 4 1
449 400 379 316