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klauspost / boundscheck.go
Last active April 1, 2016 10:46
package main
import (
"fmt"
"math/rand"
)
// This will show various cases where bounds checks can be eliminated by keeping track of
// minimum and maximum potential values of slices and variables as SSA.
func main() {
@klauspost
klauspost / memmove.go
Created November 23, 2015 13:14
memmove testing harness.
package move
import "unsafe"
func memmove(to uintptr, from uintptr, n uintptr)
func MemMove(dst, src []byte) {
memmove(uintptr(unsafe.Pointer(&dst[0])), uintptr(unsafe.Pointer(&src[0])), uintptr(len(src)))
}
@klauspost
klauspost / prefetch_amd64.go
Created December 25, 2015 10:24
//+build !appengine
package prefetch
func prefetchBS(b [][]byte)
@klauspost
klauspost / test.go
Last active January 6, 2016 12:23
filesystem test
package main
import (
"fmt"
"io/ioutil"
"log"
"os"
)
func main() {
@klauspost
klauspost / bench.txt
Last active February 17, 2016 14:37
PASS
BenchmarkShift-4 20000 69666 ns/op 940.71 MB/s
BenchmarkAnd-4 20000 66802 ns/op 981.04 MB/s
ok _/c_/Temp/shifttest 4.146s
PASS
BenchmarkShift-4 20000 68680 ns/op 954.21 MB/s
BenchmarkAnd-4 20000 67339 ns/op 973.21 MB/s
ok _/c_/Temp/shifttest 4.121s
PASS
BenchmarkShift-4 20000 68687 ns/op 954.12 MB/s
@klauspost
klauspost / compress.go
Last active June 15, 2019 08:18
//+build ignore
package main
// Adapted from : https://gist.github.com/arnehormann/65421048f56ac108f6b5
import (
"bufio"
"encoding/binary"
"flag"
@klauspost
klauspost / gzip_test.go
Created October 27, 2016 09:13
package bench
import (
"bytes"
"compress/gzip"
ogzip "github.com/klauspost/compress/gzip"
"testing"
)
var bidReq = []byte(`{"id":"50215d10a41d474f77591bff601f6ade","imp":[{"id":"86df3bc6-7bd4-44d9-64e2-584a69790229","native":{"request":"{\"ver\":\"1.0\",\"plcmtcnt\":1,\"assets\":[{\"id\":1,\"data\":{\"type\":12}},{\"id\":2,\"required\":1,\"title\":{\"len\":50}},{\"id\":3,\"required\":1,\"img\":{\"type\":1,\"w\":80,\"h\":80}},{\"id\":4,\"required\":1,\"img\":{\"type\":3,\"w\":1200,\"h\":627}},{\"id\":5,\"data\":{\"type\":3}},{\"id\":6,\"required\":1,\"data\":{\"type\":2,\"len\":100}}]}","ver":"1.0"},"tagid":"1","bidfloor":0.6,"bidfloorcur":"USD"}],"site":{"id":"1012864","domain":"www.abc.com","cat":["IAB3"],"mobile":1,"keywords":"apps,games,discovery,recommendation"},"device":{"dnt":1,"ua":"Mozilla/5.0 (Linux; U; Android 4.2.2; km-kh; SHV-E120S Build/JZO54K) AppleWebKit/534.30 (KHTML, like Gecko) Version/4.0 Mobile Safari/534.30","ip":"175.100.59.170","geo":{"lat":11.5625,"lon":104.916,"country":"KHM","r
@klauspost
klauspost / keybase.md
Created January 2, 2018 13:48

Keybase proof

I hereby claim:

  • I am klauspost on github.
  • I am klauspost (https://keybase.io/klauspost) on keybase.
  • I have a public key ASD53DNo7kJeDE1yhLrl2x5X1So398SG0jwkzn5ozDA6xAo

To claim this, I am signing this object:

@klauspost
klauspost / _sqrt.prg
Last active July 8, 2018 10:47
#
# Finds the rounded down square root of 8 bit value value in 14.
# Uses self-modifying code to store result, so
# instruction 11 (LDI 0) and the two values (14, 15) needs to be reset between runs.
#
LDA 14
SUB 15
JPC 11
STA 14
@klauspost
klauspost / gist:f5df3a3522ac4bcb3bcde448872dffe6
Last active June 1, 2019 11:06
Compression memory test
func BenchmarkCompressAllocations(b *testing.B) {
payload := []byte(strings.Repeat("Tiny payload", 20))
for j := -2; j <= 9; j++ {
b.Run("level("+strconv.Itoa(j)+")", func(b *testing.B) {
b.Run("flate", func(b *testing.B) {
b.ReportAllocs()
for i := 0; i < b.N; i++ {
w, err := flate.NewWriter(ioutil.Discard, j)