speed up rs implementation (still too slow)

This commit is contained in:
Henry Schimke
2022-10-15 10:21:19 -05:00
parent 27f491ffaa
commit 6b70f52bf6

View File

@@ -1,4 +1,4 @@
use std::{fmt}; use std::fmt;
use crate::Exceptions; use crate::Exceptions;
use std::hash::Hash; use std::hash::Hash;
@@ -64,9 +64,7 @@ pub fn get_predefined_genericgf(request: PredefinedGenericGF) -> GenericGFRef {
match request { match request {
PredefinedGenericGF::AztecData12 => &AZTEC_DATA_12, // x^12 + x^6 + x^5 + x^3 + 1, PredefinedGenericGF::AztecData12 => &AZTEC_DATA_12, // x^12 + x^6 + x^5 + x^3 + 1,
PredefinedGenericGF::AztecData10 => &AZTEC_DATA_10, // x^10 + x^3 + 1 PredefinedGenericGF::AztecData10 => &AZTEC_DATA_10, // x^10 + x^3 + 1
PredefinedGenericGF::AztecData6 | PredefinedGenericGF::MaxicodeField64 => { PredefinedGenericGF::AztecData6 | PredefinedGenericGF::MaxicodeField64 => &AZTEC_DATA_6, // x^6 + x + 1
&AZTEC_DATA_6
} // x^6 + x + 1
PredefinedGenericGF::AztecParam => &AZTEC_PARAM, // x^4 + x + 1 PredefinedGenericGF::AztecParam => &AZTEC_PARAM, // x^4 + x + 1
PredefinedGenericGF::QrCodeField256 => &QR_CODE_FIELD_256, // x^8 + x^4 + x^3 + x^2 + 1 PredefinedGenericGF::QrCodeField256 => &QR_CODE_FIELD_256, // x^8 + x^4 + x^3 + x^2 + 1
PredefinedGenericGF::DataMatrixField256 | PredefinedGenericGF::AztecData8 => { PredefinedGenericGF::DataMatrixField256 | PredefinedGenericGF::AztecData8 => {
@@ -86,7 +84,7 @@ pub fn get_predefined_genericgf(request: PredefinedGenericGF) -> GenericGFRef {
* @author Sean Owen * @author Sean Owen
* @author David Olivier * @author David Olivier
*/ */
#[derive(Debug, Clone)] #[derive(Debug, Clone, PartialEq, Eq)]
pub struct GenericGF { pub struct GenericGF {
expTable: Vec<i32>, expTable: Vec<i32>,
logTable: Vec<i32>, logTable: Vec<i32>,
@@ -97,18 +95,6 @@ pub struct GenericGF {
generatorBase: i32, generatorBase: i32,
} }
impl Hash for GenericGF {
fn hash<H: std::hash::Hasher>(&self, state: &mut H) {
self.to_string().hash(state);
}
}
impl PartialEq for GenericGF {
fn eq(&self, other: &Self) -> bool {
self.to_string() == other.to_string()
}
}
impl Eq for GenericGF {}
impl GenericGF { impl GenericGF {
/** /**
* Create a representation of GF(size) using the given primitive polynomial. * Create a representation of GF(size) using the given primitive polynomial.
@@ -130,7 +116,7 @@ impl GenericGF {
//expTable.push(x); //expTable.push(x);
expTable[i] = x; expTable[i] = x;
x *= 2; // we're assuming the generator alpha is 2 x *= 2; // we're assuming the generator alpha is 2
if x >= size.try_into().unwrap() { if x >= size as i32 {
x ^= primitive; x ^= primitive;
let sz_m_1: i32 = size as i32 - 1; let sz_m_1: i32 = size as i32 - 1;
x &= sz_m_1; x &= sz_m_1;
@@ -138,8 +124,8 @@ impl GenericGF {
} }
for i in 0..size - 1 { for i in 0..size - 1 {
//for (int i = 0; i < size - 1; i++) { //for (int i = 0; i < size - 1; i++) {
let loc: usize = expTable[i].try_into().unwrap(); let loc: usize = expTable[i] as usize;
logTable[loc] = i.try_into().unwrap(); logTable[loc] = i as i32;
} }
logTable[0] = 0; logTable[0] = 0;
@@ -157,8 +143,6 @@ impl GenericGF {
// // for (i = 0; i < 255; i++) // // for (i = 0; i < 255; i++)
// logTable[expTable[i].try_into().unwrap()] = i; // logTable[expTable[i].try_into().unwrap()] = i;
// /*Note that we rely on the fact that _gf->log[0]=0 below.*/ // /*Note that we rely on the fact that _gf->log[0]=0 below.*/
logTable[0] = 0;
Self { Self {
expTable, expTable,
logTable, logTable,
@@ -207,8 +191,8 @@ impl GenericGF {
* @return 2 to the power of a in GF(size) * @return 2 to the power of a in GF(size)
*/ */
pub fn exp(&self, a: i32) -> i32 { pub fn exp(&self, a: i32) -> i32 {
let pos: usize = a.try_into().unwrap(); // let pos: usize = a.try_into().unwrap();
return self.expTable[pos]; return self.expTable[a as usize];
} }
/** /**
@@ -218,8 +202,8 @@ impl GenericGF {
if a == 0 { if a == 0 {
return Err(Exceptions::IllegalArgumentException("".to_owned())); return Err(Exceptions::IllegalArgumentException("".to_owned()));
} }
let pos: usize = a.try_into().unwrap(); // let pos: usize = a.try_into().unwrap();
return Ok(self.logTable[pos]); return Ok(self.logTable[a as usize]);
} }
/** /**
@@ -229,10 +213,8 @@ impl GenericGF {
if a == 0 { if a == 0 {
return Err(Exceptions::ArithmeticException("".to_owned())); return Err(Exceptions::ArithmeticException("".to_owned()));
} }
let log_t_loc: usize = a.try_into().unwrap(); let log_t_loc: usize = a as usize;
let loc: usize = ((self.size as i32) - self.logTable[log_t_loc] - 1) let loc: usize = ((self.size as i32) - self.logTable[log_t_loc] - 1) as usize;
.try_into()
.unwrap();
return Ok(self.expTable[loc]); return Ok(self.expTable[loc]);
} }
@@ -243,11 +225,9 @@ impl GenericGF {
if a == 0 || b == 0 { if a == 0 || b == 0 {
return 0; return 0;
} }
let a_loc: usize = a.try_into().unwrap(); let a_loc: usize = a as usize; //.try_into().unwrap();
let b_loc: usize = b.try_into().unwrap(); let b_loc: usize = b as usize; //.try_into().unwrap();
let comb_loc: usize = (self.logTable[a_loc] + self.logTable[b_loc]) let comb_loc: usize = (self.logTable[a_loc] + self.logTable[b_loc]) as usize;
.try_into()
.unwrap();
return self.expTable[comb_loc % (self.size - 1)]; return self.expTable[comb_loc % (self.size - 1)];
} }
@@ -293,19 +273,12 @@ impl fmt::Display for GenericGF {
* *
* @author Sean Owen * @author Sean Owen
*/ */
#[derive(Debug, Clone)] #[derive(Debug, Clone, PartialEq, Eq)]
pub struct GenericGFPoly { pub struct GenericGFPoly {
field: GenericGFRef, field: GenericGFRef,
coefficients: Vec<i32>, coefficients: Vec<i32>,
} }
impl PartialEq for GenericGFPoly {
fn eq(&self, other: &Self) -> bool {
self.to_string() == other.to_string()
}
}
impl Eq for GenericGFPoly {}
impl GenericGFPoly { impl GenericGFPoly {
/** /**
* @param field the {@link GenericGF} instance representing the field to use * @param field the {@link GenericGF} instance representing the field to use
@@ -329,7 +302,8 @@ impl GenericGFPoly {
if coefficients_length > 1 && coefficients[0] == 0 { if coefficients_length > 1 && coefficients[0] == 0 {
// Leading term must be non-zero for anything except the constant polynomial "0" // Leading term must be non-zero for anything except the constant polynomial "0"
let mut first_non_zero = 1; let mut first_non_zero = 1;
while first_non_zero < coefficients_length && coefficients[first_non_zero] == 0 { while first_non_zero < coefficients_length && coefficients[first_non_zero] == 0
{
first_non_zero += 1; first_non_zero += 1;
} }
if first_non_zero == coefficients_length { if first_non_zero == coefficients_length {
@@ -399,10 +373,7 @@ impl GenericGFPoly {
for i in 1..size { for i in 1..size {
//for (int i = 1; i < size; i++) { //for (int i = 1; i < size; i++) {
result = GenericGF::addOrSubtract( result = GenericGF::addOrSubtract(
self.field self.field.multiply(a as i32, result as i32),
.multiply(a.try_into().unwrap(), result.try_into().unwrap())
.try_into()
.unwrap(),
self.coefficients[i], self.coefficients[i],
); );
} }
@@ -469,13 +440,7 @@ impl GenericGFPoly {
//for (int j = 0; j < bLength; j++) { //for (int j = 0; j < bLength; j++) {
product[i + j] = GenericGF::addOrSubtract( product[i + j] = GenericGF::addOrSubtract(
product[i + j], product[i + j],
self.field self.field.multiply(aCoeff, bCoefficients[j]),
.multiply(
aCoeff.try_into().unwrap(),
bCoefficients[j].try_into().unwrap(),
)
.try_into()
.unwrap(),
); );
} }
} }
@@ -494,9 +459,7 @@ impl GenericGFPoly {
let mut product = vec![0; size]; let mut product = vec![0; size];
for i in 0..size { for i in 0..size {
//for (int i = 0; i < size; i++) { //for (int i = 0; i < size; i++) {
product[i] = self product[i] = self.field.multiply(self.coefficients[i], scalar);
.field
.multiply(self.coefficients[i], scalar.try_into().unwrap());
} }
return GenericGFPoly::new(self.field, &product).unwrap(); return GenericGFPoly::new(self.field, &product).unwrap();
} }
@@ -514,9 +477,6 @@ impl GenericGFPoly {
degree: usize, degree: usize,
coefficient: i32, coefficient: i32,
) -> Result<GenericGFPoly, Exceptions> { ) -> Result<GenericGFPoly, Exceptions> {
if degree < 0 {
return Err(Exceptions::IllegalArgumentException("".to_owned()));
}
if coefficient == 0 { if coefficient == 0 {
return Ok(self.getZero()); return Ok(self.getZero());
} }
@@ -680,16 +640,11 @@ impl ReedSolomonDecoder {
*/ */
pub fn decode(&self, received: &mut Vec<i32>, twoS: i32) -> Result<(), Exceptions> { pub fn decode(&self, received: &mut Vec<i32>, twoS: i32) -> Result<(), Exceptions> {
let poly = GenericGFPoly::new(self.field, received).unwrap(); let poly = GenericGFPoly::new(self.field, received).unwrap();
let mut syndromeCoefficients = vec![0; twoS.try_into().unwrap()]; let mut syndromeCoefficients = vec![0; twoS as usize];
let mut noError = true; let mut noError = true;
for i in 0..twoS { for i in 0..twoS {
//for (int i = 0; i < twoS; i++) { //for (int i = 0; i < twoS; i++) {
let eval = poly.evaluateAt( let eval = poly.evaluateAt(self.field.exp(i + self.field.getGeneratorBase()) as usize);
self.field
.exp(i + self.field.getGeneratorBase())
.try_into()
.unwrap(),
);
let len = syndromeCoefficients.len(); let len = syndromeCoefficients.len();
syndromeCoefficients[len - 1 - i as usize] = eval; syndromeCoefficients[len - 1 - i as usize] = eval;
if eval != 0 { if eval != 0 {
@@ -708,9 +663,9 @@ impl ReedSolomonDecoder {
} }
}; };
let sigmaOmega = self.runEuclideanAlgorithm( let sigmaOmega = self.runEuclideanAlgorithm(
&GenericGF::buildMonomial(self.field, twoS.try_into().unwrap(), 1), &GenericGF::buildMonomial(self.field, twoS as usize, 1),
&syndrome, &syndrome,
twoS.try_into().unwrap(), twoS as usize,
)?; )?;
let sigma = &sigmaOmega[0]; let sigma = &sigmaOmega[0];
let omega = &sigmaOmega[1]; let omega = &sigmaOmega[1];
@@ -718,7 +673,7 @@ impl ReedSolomonDecoder {
let errorMagnitudes = self.findErrorMagnitudes(&omega, &errorLocations); let errorMagnitudes = self.findErrorMagnitudes(&omega, &errorLocations);
for i in 0..errorLocations.len() { for i in 0..errorLocations.len() {
//for (int i = 0; i < errorLocations.length; i++) { //for (int i = 0; i < errorLocations.length; i++) {
let log_value = self.field.log(errorLocations[i].try_into().unwrap())?; let log_value = self.field.log(errorLocations[i] as i32)?;
if log_value > received.len() as i32 - 1 { if log_value > received.len() as i32 - 1 {
return Ok(()); return Ok(());
} }
@@ -728,7 +683,8 @@ impl ReedSolomonDecoder {
"Bad error location".to_owned(), "Bad error location".to_owned(),
)); ));
} }
received[position as usize] = GenericGF::addOrSubtract(received[position as usize], errorMagnitudes[i]); received[position as usize] =
GenericGF::addOrSubtract(received[position as usize], errorMagnitudes[i]);
} }
Ok(()) Ok(())
} }
@@ -785,7 +741,8 @@ impl ReedSolomonDecoder {
let scale = self let scale = self
.field .field
.multiply(r.getCoefficient(r.getDegree()), dltInverse); .multiply(r.getCoefficient(r.getDegree()), dltInverse);
q = match q.addOrSubtract(&GenericGF::buildMonomial(self.field, degreeDiff, scale)) { q = match q.addOrSubtract(&GenericGF::buildMonomial(self.field, degreeDiff, scale))
{
Ok(res) => res, Ok(res) => res,
Err(_err) => { Err(_err) => {
return Err(Exceptions::ReedSolomonException( return Err(Exceptions::ReedSolomonException(
@@ -861,7 +818,7 @@ impl ReedSolomonDecoder {
let numErrors = errorLocator.getDegree(); let numErrors = errorLocator.getDegree();
if numErrors == 1 { if numErrors == 1 {
// shortcut // shortcut
return Ok(vec![errorLocator.getCoefficient(1).try_into().unwrap()]); return Ok(vec![errorLocator.getCoefficient(1) as usize]);
} }
let mut result: Vec<usize> = vec![0; numErrors]; let mut result: Vec<usize> = vec![0; numErrors];
@@ -872,8 +829,8 @@ impl ReedSolomonDecoder {
break; break;
} }
if errorLocator.evaluateAt(i) == 0 { if errorLocator.evaluateAt(i) == 0 {
result[e] = match self.field.inverse(i.try_into().unwrap()) { result[e] = match self.field.inverse(i as i32) {
Ok(res) => res.try_into().unwrap(), Ok(res) => res as usize,
Err(_err) => { Err(_err) => {
return Err(Exceptions::ReedSolomonException( return Err(Exceptions::ReedSolomonException(
"ArithmetricException".to_owned(), "ArithmetricException".to_owned(),
@@ -901,10 +858,7 @@ impl ReedSolomonDecoder {
let mut result = vec![0; s]; let mut result = vec![0; s];
for i in 0..s { for i in 0..s {
//for (int i = 0; i < s; i++) { //for (int i = 0; i < s; i++) {
let xiInverse = self let xiInverse = self.field.inverse(errorLocations[i] as i32).unwrap();
.field
.inverse(errorLocations[i].try_into().unwrap())
.unwrap();
let mut denominator = 1; let mut denominator = 1;
for j in 0..s { for j in 0..s {
//for (int j = 0; j < s; j++) { //for (int j = 0; j < s; j++) {
@@ -913,9 +867,7 @@ impl ReedSolomonDecoder {
// GenericGF.addOrSubtract(1, field.multiply(errorLocations[j], xiInverse))); // GenericGF.addOrSubtract(1, field.multiply(errorLocations[j], xiInverse)));
// Above should work but fails on some Apple and Linux JDKs due to a Hotspot bug. // Above should work but fails on some Apple and Linux JDKs due to a Hotspot bug.
// Below is a funny-looking workaround from Steven Parkes // Below is a funny-looking workaround from Steven Parkes
let term = self let term = self.field.multiply(errorLocations[j] as i32, xiInverse);
.field
.multiply(errorLocations[j].try_into().unwrap(), xiInverse);
let termPlus1 = if (term & 0x1) == 0 { let termPlus1 = if (term & 0x1) == 0 {
term | 1 term | 1
} else { } else {
@@ -925,7 +877,7 @@ impl ReedSolomonDecoder {
} }
} }
result[i] = self.field.multiply( result[i] = self.field.multiply(
errorEvaluator.evaluateAt(xiInverse.try_into().unwrap()), errorEvaluator.evaluateAt(xiInverse as usize),
self.field.inverse(denominator).unwrap(), self.field.inverse(denominator).unwrap(),
); );
if self.field.getGeneratorBase() != 0 { if self.field.getGeneratorBase() != 0 {
@@ -1026,7 +978,7 @@ impl ReedSolomonEncoder {
info_coefficients[0..data_bytes].clone_from_slice(&to_encode[0..data_bytes]); info_coefficients[0..data_bytes].clone_from_slice(&to_encode[0..data_bytes]);
//System.arraycopy(toEncode, 0, infoCoefficients, 0, dataBytes); //System.arraycopy(toEncode, 0, infoCoefficients, 0, dataBytes);
let mut info = GenericGFPoly::new(fld, &info_coefficients)?; let mut info = GenericGFPoly::new(fld, &info_coefficients)?;
info = info.multiply_by_monomial(ec_bytes.try_into().unwrap(), 1)?; info = info.multiply_by_monomial(ec_bytes, 1)?;
let remainder = &info.divide(&generator)?.1; let remainder = &info.divide(&generator)?.1;
let coefficients = remainder.getCoefficients(); let coefficients = remainder.getCoefficients();
let num_zero_coefficients = ec_bytes - coefficients.len(); let num_zero_coefficients = ec_bytes - coefficients.len();