acdimalev

#include <assert.h>
#include <fcntl.h>
#include <stdbool.h>
#include <stdint.h>
#include <stdlib.h>
#include <stdio.h>
#include <termios.h>
#include <unistd.h>
#include <sys/ioctl.h>
#include <sys/timerfd.h>

acdimalev

#!/bin/sh
r2 -qc "e anal.bb.maxsize=2048;s sym.$2;af;agfj" "$1" | python3 control-flow-graph.py

acdimalev

set a base directory (just to make things easier)

$ basedir="$(pwd)"

set up Emscripten https://kripken.github.io/emscripten-site/docs/getting_started/downloads.html

$ cd "$basedir"

$ git clone https://github.com/juj/emsdk.git

acdimalev

00: 902  !..! .... ..!.  mov r0, 2
01: cf0  !!.. !!!! ....  mov [0xf0], r0
02: 901  !..! .... ...!  mov r0, 1
03: cf1  !!.. !!!! ...!  mov [0xf1], r0
04: 912  !..! ...! ..!.  mov r1, 2
05: 923  !..! ..!. ..!!  mov r2, 3
06: dff  !!.! !!!! !!!!  mov r0, [0xff]
07: a19  !.!. ...! !..!  mov [r1:r9], r0
08: dff  !!.! !!!! !!!!  mov r0, [0xff]
09: a29  !.!. ..!. !..!  mov [r2:r9], r0

acdimalev

# https://docs.oracle.com/javase/specs/jvms/se7/html/jvms-6.html

from bs4 import BeautifulSoup
soup = BeautifulSoup(open('jvms-6.html', encoding='ISO8859').read(), 'html.parser')

ops = {
    div['title']: {
        'words': len(div.find('div', {'class': 'literallayout'}).find_all('br')) - 1,
        'opcodes': [
            int(p.text.split(' ')[2])

acdimalev

# this builds on https://gist.github.com/acdimalev/ff75aa864e49a41231d19c921132faf1

# double-word division takes three input parameters and outputs two
# for ALU-type usage, it makes sense to re-use two of the input registers as output registers

# A : dividend high-word -> remainder
# B : dividend low-word -> quotient
# C : divisor

# long-division is accomplished by zeroing out the dividend high-word,

acdimalev

// modprobe snd_pcm_oss

#include <fcntl.h>
#include <linux/soundcard.h>
#include <math.h>
#include <stdbool.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/ioctl.h>

acdimalev

from math import log
from random import random, randrange


sample = lambda: (randrange(1, 101), random())

q = [
    (1 - y) * log(x) + y * x
    for (x, y)
    in (sample() for _ in range(1000))

acdimalev

#!/usr/bin/env python3

# interactive log-log profiling visualizer with scales I personally find useful for microprocessor-scale optimizations

# usage: ./profile <depth> <filename>
#
# "depth" is basically the height of the graph
# it controlls how many samples are stored at any given time

# legend for reading the output

acdimalev

from socket import create_server

MAX_SOCKETS = 1024
BUFFER_SIZE = 4096

sockets = [(0, None)] * MAX_SOCKETS
buffers = [b''] * MAX_SOCKETS

connections = []