lemire

/* auto-generated on 2022-10-06 13:43:02 +0000. Do not edit! */
// dofile: invoked with prepath=/home/lemire/CVS/github/simdutf/include, filename=simdutf.h
/* begin file include/simdutf.h */
#ifndef SIMDUTF_H
#define SIMDUTF_H
#include <cstring>

// dofile: invoked with prepath=/home/lemire/CVS/github/simdutf/include, filename=simdutf/compiler_check.h
/* begin file include/simdutf/compiler_check.h */
#ifndef SIMDUTF_COMPILER_CHECK_H

lemire

#include <fstream>
#include <iostream>

int main() {
  char16_t output_buffer[] = u"hello world";
  size_t len = sizeof(output_buffer) / sizeof(char16_t);
  std::ofstream out("output.ut16.txt", std::ios::binary | std::ios::trunc);
  out.write(reinterpret_cast<char *>(output_buffer), len * sizeof(char16_t));
  std::cout << "wrote " << out.tellp() << " bytes" << std::endl;
  out.close();

lemire

from math import *

def convert_to_degree(x):
  return [int(x[0] / (2 * pi) *360),int(x[1] / (2 * pi) *360),int(x[2] / (2 * pi) *360)]

def toangles(q):
    sqw = q[3] * q[3]
    sqx = q[0] * q[0]
    sqy = q[1] * q[1]
    sqz = q[2] * q[2]

lemire

Here is how to test rcppsimdjson.

• Install docker.
• Grab rcppsimdjson from GitHub.

Next, you want to create a file called 'Dockerfile'. You may put this file inside the root rcppsimdjson repository.

The file may have the following content: (there are more examples at https://github.com/RcppCore/Rcpp/tree/master/docker/ci-3.4 )

lemire

#include <stdio.h>
#include <stdlib.h>

int main(int argc, char **argv) {
  if (argc < 2) {
    perror("provide a file argument");
  }
  FILE *pFile = fopen(argv[1], "rb");
  if (pFile == NULL)
    perror("Error opening file");

lemire

	.globl	_compute_two            ; -- Begin function compute_two
	.p2align	2
_compute_two:                           ; @compute_two
	.cfi_startproc
; %bb.0:
Lloh0:
	adrp	x8, _M@PAGE
Lloh1:
	ldr	x8, [x8, _M@PAGEOFF]
	tst	x8, #0x7fffffffffffffff

lemire

# Copy this file as CMakeLists.txt in
# some directory. With a recent CMake
# (at least 3.15), in this directory do
#
# cmake -B build .
# cmake --build build
# ./build/repro
#
#
cmake_minimum_required(VERSION 3.15)

lemire

namespace {
/**
 * make_uint8x16_t initializes a SIMD register (uint8x16_t).
 * This is needed because, incredibly, the syntax uint8x16_t x = {1,2,3...}
 * is not recognized under Visual Studio! This is a workaround.
 * Using a std::initializer_list<uint8_t>  as a parameter resulted in
 * inefficient code. With the current approach, if the parameters are
 * compile-time constants,
 * GNU GCC compiles it to ldr, the same as uint8x16_t x = {1,2,3...}.

lemire

docker run -it --privileged ubuntu bash

apt-get update
apt-get install linux-tools-generic
/usr/lib/linux-tools/5.4.0-28-generic/perf stat ls

lemire

// returns true if the provided byte value is a
// "continuing" UTF-8 value, that is, if it starts with
// 0b10...
static inline bool is_utf8_continuing(char c) {
  // in 2 complement's notation, values start at 0b10000 (-128)... and
  // go up to 0b11111 (-1)... so we want all values from -128 to -65 (which is 0b10111111)
  return ((signed char)c) <= -65;
}