EvoApprox8B

/***
* This code is a part of EvoApproxLib library (ehw.fit.vutbr.cz/approxlib) distributed under The MIT License.
* When used, please cite the following article(s): V. Mrazek, R. Hrbacek, Z. Vasicek and L. Sekanina, "EvoApprox8b: Library of approximate adders and multipliers for circuit design and benchmarking of approximation methods". Design, Automation & Test in Europe Conference & Exhibition (DATE), 2017, Lausanne, 2017, pp. 258-261. doi: 10.23919/DATE.2017.7926993 
* This file contains a circuit from evoapprox8b dataset. Note that a new version of library was already published.
***/
#include <stdint.h>
#include <stdlib.h>

/// Approximate function add8_RippleCarryAdder
///  Library = EvoApprox8b
///  Circuit = add8_RCA
///  Area   (180) = 920
///  Delay  (180) = 1.680
///  Power  (180) = 339.90
///  Area   (45) = 67
///  Delay  (45) = 0.630
///  Power  (45) = 32.96
///  Nodes = 8
///  HD = 0
///  MAE = 0.00000
///  MSE = 0.00000
///  MRE = 0.00 %
///  WCE = 0
///  WCRE = 0 %
///  EP = 0.0 %
uint16_t add8_RippleCarryAdder(uint8_t a, uint8_t b)
{
  uint16_t c = 0;
  uint8_t n0 = (a >> 0) & 0x1;
  uint8_t n2 = (a >> 1) & 0x1;
  uint8_t n4 = (a >> 2) & 0x1;
  uint8_t n6 = (a >> 3) & 0x1;
  uint8_t n8 = (a >> 4) & 0x1;
  uint8_t n10 = (a >> 5) & 0x1;
  uint8_t n12 = (a >> 6) & 0x1;
  uint8_t n14 = (a >> 7) & 0x1;
  uint8_t n16 = (b >> 0) & 0x1;
  uint8_t n18 = (b >> 1) & 0x1;
  uint8_t n20 = (b >> 2) & 0x1;
  uint8_t n22 = (b >> 3) & 0x1;
  uint8_t n24 = (b >> 4) & 0x1;
  uint8_t n26 = (b >> 5) & 0x1;
  uint8_t n28 = (b >> 6) & 0x1;
  uint8_t n30 = (b >> 7) & 0x1;
  uint8_t n32;
  uint8_t n33;
  uint8_t n34;
  uint8_t n35;
  uint8_t n36;
  uint8_t n37;
  uint8_t n38;
  uint8_t n39;
  uint8_t n40;
  uint8_t n41;
  uint8_t n42;
  uint8_t n43;
  uint8_t n44;
  uint8_t n45;
  uint8_t n46;
  uint8_t n47;

  n32 = n0 ^ n16;
  n33 = n0 & n16;
  n34 = (n2 ^ n18) ^ n33;
  n35 = (n2 & n18) | (n18 & n33) | (n2 & n33);
  n36 = (n4 ^ n20) ^ n35;
  n37 = (n4 & n20) | (n20 & n35) | (n4 & n35);
  n38 = (n6 ^ n22) ^ n37;
  n39 = (n6 & n22) | (n22 & n37) | (n6 & n37);
  n40 = (n8 ^ n24) ^ n39;
  n41 = (n8 & n24) | (n24 & n39) | (n8 & n39);
  n42 = (n10 ^ n26) ^ n41;
  n43 = (n10 & n26) | (n26 & n41) | (n10 & n41);
  n44 = (n12 ^ n28) ^ n43;
  n45 = (n12 & n28) | (n28 & n43) | (n12 & n43);
  n46 = (n14 ^ n30) ^ n45;
  n47 = (n14 & n30) | (n30 & n45) | (n14 & n45);

  c |= (n32 & 0x1) << 0;
  c |= (n34 & 0x1) << 1;
  c |= (n36 & 0x1) << 2;
  c |= (n38 & 0x1) << 3;
  c |= (n40 & 0x1) << 4;
  c |= (n42 & 0x1) << 5;
  c |= (n44 & 0x1) << 6;
  c |= (n46 & 0x1) << 7;
  c |= (n47 & 0x1) << 8;

  return c;
}