SPO600 Lab 6

#include <stdio.h>
#include <stdbool.h>
#include <arm_sve.h>
#include "vol.h"

int main()
{
    int x;
    int ttl = 0;

    // ---- Create in[] and out[] arrays
    int64_t *in;
    int64_t *out;
    in = (int64_t *)calloc(SAMPLES, sizeof(int64_t));
    out = (int64_t *)calloc(SAMPLES, sizeof(int64_t));

    // ---- Create dummy samples in in[]
    vol_createsample(in, SAMPLES);

    // ---- This is the part we're interested in!
    // ---- Scale the samples from in[], placing results in out[]

    /*for (x = 0; x < SAMPLES; x++) {
        out[x]=(int64_t) ((float) (VOLUME/100.0) * (float) in[x]);
    }*/

    svbool_t pg; // [1]
    svint64_t svin; // [1]
    svfloat64_t svv;// [1]
    const float64_t division = (float)(VOLUME / 100.0); // [2]
    for (int i = 0; i < SAMPLES; i += svcntd()) // [3]
    {
        pg = svwhilelt_b64(i, SAMPLES); // [4]
        svin = svld1(pg, &in[i]); // [5]
        svv = svld1(pg, &division); // [6]
        svst1(pg, &out[i], svcvt_s64_z(pg, svmul_f64_z(pg, svv, svcvt_f64_z(pg, svin)))); // [7]
    }

    // ---- This part sums the samples. (Why is this needed?)
    for (x = 0; x < SAMPLES; x++)
    {
        ttl = (ttl + out[x]) % 1000;
    }

    // ---- Print the sum of the samples. (Why is this needed?)
    printf("Result: %d\n", ttl);

    return 0;
}

The above code is my SVE2 implementation for the vol0.c program, specially for the scale volume function:

[1]: Declarations of vectors and guarded predicate for the loop.

[2]: Scale rate defined by VOLUME in vol.h

[3]: The loop with i increase by  the number of double-precision lanes in the vector.

[4]: Verify loop predicate after each loop.

[5]: Load a vector with data of samples.

[6]: Load another vector with the scale volume rate

[7]: Do multiply between 2 vectors and some conversions to mimic the original algorithm.

The hard part in the lab is that it is hard to find public discussions about SVE2 code, and I have to look at the instruction references.

Comments

Post a Comment

Popular posts from this blog

SPO600 Lab 2

Image
 Lab 2, where I have a given 6502 assembly code: lda #$00 ; set a pointer at $40 to point to $0200 sta $40 lda #$02 sta $41 lda #$07 ; colour number ldy #$00 ; set index to 0 loop: sta ($40),y ; set pixel at the address (pointer)+Y iny ; increment index bne loop ; continue until done the page inc $41 ; increment the page ldx $41 ; get the current page number cpx #$06 ; compare with 6 bne loop ; continue until done all pages My job is to play around with the code, calculate the performance of the given code, and try to optimize the code to have a better performance. First, starting to run the code on  http://6502.cdot.systems/  - a website that stimulates a 6502 emulator, I got a result of a yellow screen, which consists of 4 pages.  Let's look at the performance by calculating the number of cycles and cycle count. We will do this on Microsoft Excel to have a clear perspective. After doing some calculations on Excel, I got a result of 0.012 seconds. How did I fin
Read more

SPO600 Lab 1

Image
 In the first lab of SPO600 course, my work is to explore two open-source software projects. As an Android user, who like to root my phone (I have a Pixel 6, and I saw you are having one too), I am using several applications that take advantage of root permissions. One of those apps is Adaway – an application that blocks ads system-wide. Source: https://adaway.org/ Looking at its source code on Github, I found the software is distributed under GNU GENERAL PUBLIC LICENSE - Version 3. In short, PGLv3 is a copyleft license, which requires copies or modifications of the source must also be released under the same license. Everyone can make contributions to the project by reporting bugs, suggesting enhancements, or translating to languages. For example, look at the most commented pull request – pull request number 784: Source: https://github.com/AdAway/AdAway/pull Source: https://github.com/AdAway/AdAway/pull/784 There were 21 commits and months needed in total to resolve the issue. The
Read more

SPO600 Lab 3

Image
  For lab 3, my task is to write a simple program using the output screen and to make use of math operation in 6502 assembly. Even though it is a simple program with basic tasks, it is not that easy to write the program in assembly language, while we can do this easily in modern language. Especially we just learned a whole new concept for several classes. Luckily, the lab says: I decided to write a subtraction calculator. Inspired by the adding calculator from my professor’s Github:  (https://github.com/ctyler/6502js-code/blob/master/adding-calculator.6502) I made an investigation to understand how the code works, so later I can modify it to become a subtraction calculator. With a limited amount of time learning 6502 assembly and not many resources on the internet, I could only understand the main part of the program, but it was enough for me to make an incomplete subtraction calculator. My input process is identical to the source code. The only difference is instead of adding tw
Read more