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pcordes / bittnkr-uniq-non-atomic-testcase.cpp
Created January 7, 2020 22:25
bittnkr/uniq non-atomic testcase.cpp
// compile with g++ -m32 -O1 -pthread -Wall
// based on sandbox/hello.cpp but parameterized for qtype instead of int
// and queuing values that have non-zero high halves (and aren't all the same as each other!!!)
#include <pthread.h>
#include <stdio.h>
#include <thread>
#include <vector>
pcordes / loop-up-down.asm
Created April 11, 2017 20:47
copy + bswap in-place vs. copy + swap on the fly, to simulate mmap vs. read
;; 3 versions, only one enabled with %if 1 NASM/YASM preprocessor stuff, like C #if 0 / #if 1
;; shuffle on the fly
;; copy + in-place
;; read-only up/down/bidir
;;; ~/bin/asm-link loop-up-down.asm && disas loop-up-down && stat -etask-clock,page-faults,cycles,L1-dcache-loads,L1-dcache-load-misses,LLC-loads,LLC-load-misses,instructions,dtlb_store_misses.miss_causes_a_walk -r4 ./loop-up-down
;;;~/bin/asm-link loop-up-down.asm && rm loop-up-down.o && disas loop-up-down && nice stat -etask-clock,page-faults,cycles,L1-dcache-loads,LLC-loads,LLC-load-misses,instructions,dtlb_store_misses.miss_causes_a_walk,dtlb_load_misses.stlb_hit,dtlb_load_misses.miss_causes_a_walk -r3 ./loop-up-down
default rel
// x86 SIMD string to uppercase
// See
#include <stdio.h>
#include <stdint.h>
#include <string.h>
#include <strings.h> // for ffs
#include <ctype.h>
#include <immintrin.h>