Integer vs Arbitrary Precise Integer Intel HLS

Altera_Forum · ‎02-12-2018

Hello all great people and Anand,

Below is the code snippet. I am using Intel HLS tool. The data type used in below given code is integer. I want to compare the result of integer data type with arbitrary precise integer represented as ac_int <W> in Intel HLS tool through AC data type library of Intel HLS tool. My question is what should be the exact representation of ac_int <W> in terms of 'W' for input arrays, dout, acc, a_reg, sub and sub2 for less latency and less resource utilization.

I want to use the exact code for precise integer type instead of native integer and later compare the results of integer and arbitrary precise data type.

void diff_sq_acc(int a[N], int b[N], int *dout)

{

unsigned char i;

int acc= 0;

int a_reg, b_reg, sub, sub2;

for(i=0; i<N; i++)

{

a_reg = a;

b_reg = b;

sub = a_reg - b_reg;

sub2 = sub*sub;

acc += sub2;

}

*dout = acc;

}

Altera_Forum · ‎02-12-2018

Hi,

You can try to optimize as per you design requriments.


# include "HLS/hls.h"
# include <stdio.h>
# include "HLS/ac_int.h"
# include "HLS/ac_fixed.h"
# include "HLS/extendedmath.h"
# include "HLS/math.h"
typedef ac_int<8, false> fixed_8_t;
typedef ac_int<16, false> fixed_16_t;
# define N 2
component void dut(fixed_8_t a, fixed_8_t b, fixed_8_t *dout)
{
unsigned int i;
fixed_16_t acc= 0;
fixed_8_t a_reg, b_reg, sub;
fixed_16_t sub2;
for(i=0; i<N; i++)
{
a_reg = a;
b_reg = b;
sub = a_reg - b_reg;
sub2 = sub*sub;
acc += sub2;
}
*dout = acc;
  
 }
int main() {
	fixed_8_t z;
	 fixed_16_t ip = &z;
	fixed_8_t x={128,128};
	fixed_8_t y={128,128};
  dut(x,y,&z);
  return 0;
}

let me know if this has helped resolve the issue you are facing or if you need any further assistance.

PS:Same as thread https://alteraforum.com/forum/showthread.php?t=57668&page=2

Best Regards,

Anand Raj Shankar

(This message was posted on behalf of Intel Corporation)

Altera_Forum · ‎02-12-2018

Dear Anand,

thanks ! it works...i think there was a type error in your code... *dout should be fixed_16_t..... right ?

Altera_Forum · ‎02-12-2018

Hi,

There was no error in code.

Yes logically it should be fixed_16_t .

let me know if you need any further assistance.

Best Regards,

Anand Raj Shankar

(This message was posted on behalf of Intel Corporation)

Altera_Forum · ‎02-12-2018

ok got your point...thanks !