ayo/kitty
1
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

Speedup Memset for single val

Browse source
This commit is contained in:
Kovid Goyal 2023-07-04 17:52:58 +05:30
parent 678ad627b2
commit ed6e3dfe2c
No known key found for this signature in database
GPG key ID: 06BC317B515ACE7C
1 changed files with 13 additions and 6 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

19
tools/utils/misc.go
View file

@ -136,7 +136,8 @@ func Min[T constraints.Ordered](a T, items ...T) (ans T) {
}
func Memset[T any](dest []T, pattern ...T) []T {
if len(pattern) == 0 {
switch len(pattern) {
case 0:
var zero T
switch any(zero).(type) {
case byte: // special case this as the compiler can generate efficient code for memset of a byte slice to zero
@ -150,11 +151,17 @@ func Memset[T any](dest []T, pattern ...T) []T {
}
}
return dest
}
bp := copy(dest, pattern)
for bp < len(dest) {
copy(dest[bp:], dest[:bp])
bp *= 2
case 1:
val := pattern[0]
for i := range dest {
dest[i] = val
}
default:
bp := copy(dest, pattern)
for bp < len(dest) {
copy(dest[bp:], dest[:bp])
bp *= 2
}
}
return dest
}