NB. 32 bit adder (circuit model)
NB. Constructed from 8 - fourBitAdder's

require 'circuits.ijs'

dtb =: (32 # 2) & #:

signed_value =: monad define 
  digits =. # y.
   if. 1 = 1 take y.
    do. ((digits copy 2) base x: y. ) - 2^ x: digits
    else. (digits copy 2) base x: y.
   end.
)

btd =: signed_value

NB.  thirtytwoBitAdder

thirtytwoBitAdder =: monad define 
'a b cin' =. dtb y.
t0 =. fourBitAdder (28 29 30 31 { a) , (28 29 30 31 { b) , 31 { cin
t1 =. fourBitAdder (24 25 26 27 { a) , (24 25 26 27 { b) , wireOutput 0 ; t0
t2 =. fourBitAdder (20 21 22 23 { a) , (20 21 22 23 { b) , wireOutput 0 ; t1
t3 =. fourBitAdder (16 17 18 19 { a) , (16 17 18 19 { b) , wireOutput 0 ; t2
t4 =. fourBitAdder (12 13 14 15 { a) , (12 13 14 15 { b) , wireOutput 0 ; t3
t5 =. fourBitAdder (8 9 10 11 { a) , (8 9 10 11 { b) , wireOutput 0 ; t4
t6 =. fourBitAdder (4 5 6 7 { a) , (4 5 6 7 { b) , wireOutput 0 ; t5
t7 =. fourBitAdder (0 1 2 3 { a) , (0 1 2 3 { b) , wireOutput 0 ; t6
btd (wireOutput   1 2 3 4 ; t7) , (wireOutput 1 2 3 4 ; t6) , (wireOutput 1 2 3 4 ; t5) , (wireOutput 1 2 3 4 ; t4) , (wireOutput 1 2 3 4 ; t3) , (wireOutput 1 2 3 4 ; t2) , (wireOutput 1 2 3 4 ; t1) , wireOutput 1 2 3 4 ; t0
)
 
NB.  thirtytwoBitALU

thirtytwoBitALU =: monad define 
'a b cin' =. y.
a =. dtb a
b =. bitXor rank 1 cin,rank 0 dtb b
t0 =. fourBitAdder (28 29 30 31 { a) , (28 29 30 31 { b) , cin
t1 =. fourBitAdder (24 25 26 27 { a) , (24 25 26 27 { b) , wireOutput 0 ; t0
t2 =. fourBitAdder (20 21 22 23 { a) , (20 21 22 23 { b) , wireOutput 0 ; t1
t3 =. fourBitAdder (16 17 18 19 { a) , (16 17 18 19 { b) , wireOutput 0 ; t2
t4 =. fourBitAdder (12 13 14 15 { a) , (12 13 14 15 { b) , wireOutput 0 ; t3
t5 =. fourBitAdder (8 9 10 11 { a) , (8 9 10 11 { b) , wireOutput 0 ; t4
t6 =. fourBitAdder (4 5 6 7 { a) , (4 5 6 7 { b) , wireOutput 0 ; t5
t7 =. fourBitAdder (0 1 2 3 { a) , (0 1 2 3 { b) , wireOutput 0 ; t6
btd (wireOutput   1 2 3 4 ; t7) , (wireOutput 1 2 3 4 ; t6) , (wireOutput 1 2 3 4 ; t5) , (wireOutput 1 2 3 4 ; t4) , (wireOutput 1 2 3 4 ; t3) , (wireOutput 1 2 3 4 ; t2) , (wireOutput 1 2 3 4 ; t1) , wireOutput 1 2 3 4 ; t0
)
 
NB. synonym for thirtytwoBitAdder

tba =: thirtytwoBitAdder

NB. A test suite of border-line values

test =: transpose 0 1 0x ,. _1 1 0x ,. _1 1 1x ,. 4294967295 1 0x ,. _4294967296 1 0x ,. 4294967295 2 0x ,. _4294967296 _1 0x ,. 4294967295 4294967295 0x ,. _4294967296 _4294967296 0x ,. 3 2 1x

NB. To test outputs, test ,. tba rows test
NB. To test outputs, test ,. thirtytwoBitALU rows test