| Message ID | 20190206145850.22003-6-adhemerval.zanella@linaro.org |
|---|---|
| State | New |
| Headers | show |
| Series | [1/7] wcsmbs: optimize wcpcpy | expand |
If no one opposes it, I will commit this shortly. On 06/02/2019 12:58, Adhemerval Zanella wrote: > This patch rewrites wcsncpy using wcsnlen, wmemset, and wmemcpy. This is > similar to the optimization done on strncpy by f6482cf29d and 6423d4754c. > > Checked on x86_64-linux-gnu. > > * wcsmbs/wcsncpy.c (__wcsncpy): Rewrite using wcsnlen, wmemset, and > wmemcpy. > --- > wcsmbs/wcsncpy.c | 60 ++++-------------------------------------------- > 1 file changed, 4 insertions(+), 56 deletions(-) > > diff --git a/wcsmbs/wcsncpy.c b/wcsmbs/wcsncpy.c > index 2fd523c815..d5d7f4ad86 100644 > --- a/wcsmbs/wcsncpy.c > +++ b/wcsmbs/wcsncpy.c > @@ -26,62 +26,10 @@ > wchar_t * > __wcsncpy (wchar_t *dest, const wchar_t *src, size_t n) > { > - wint_t c; > - wchar_t *const s = dest; > - > - --dest; > - > - if (n >= 4) > - { > - size_t n4 = n >> 2; > - > - for (;;) > - { > - c = *src++; > - *++dest = c; > - if (c == L'\0') > - break; > - c = *src++; > - *++dest = c; > - if (c == L'\0') > - break; > - c = *src++; > - *++dest = c; > - if (c == L'\0') > - break; > - c = *src++; > - *++dest = c; > - if (c == L'\0') > - break; > - if (--n4 == 0) > - goto last_chars; > - } > - n = n - (dest - s) - 1; > - if (n == 0) > - return s; > - goto zero_fill; > - } > - > - last_chars: > - n &= 3; > - if (n == 0) > - return s; > - > - do > - { > - c = *src++; > - *++dest = c; > - if (--n == 0) > - return s; > - } > - while (c != L'\0'); > - > - zero_fill: > - do > - *++dest = L'\0'; > - while (--n > 0); > - > - return s; > + size_t size = __wcsnlen (src, n); > + if (size != n) > + __wmemset (dest + size, L'\0', n - size); > + return __wmemcpy (dest, src, size); > } > #ifndef WCSNCPY > weak_alias (__wcsncpy, wcsncpy) >
diff --git a/wcsmbs/wcsncpy.c b/wcsmbs/wcsncpy.c index 2fd523c815..d5d7f4ad86 100644 --- a/wcsmbs/wcsncpy.c +++ b/wcsmbs/wcsncpy.c @@ -26,62 +26,10 @@ wchar_t * __wcsncpy (wchar_t *dest, const wchar_t *src, size_t n) { - wint_t c; - wchar_t *const s = dest; - - --dest; - - if (n >= 4) - { - size_t n4 = n >> 2; - - for (;;) - { - c = *src++; - *++dest = c; - if (c == L'\0') - break; - c = *src++; - *++dest = c; - if (c == L'\0') - break; - c = *src++; - *++dest = c; - if (c == L'\0') - break; - c = *src++; - *++dest = c; - if (c == L'\0') - break; - if (--n4 == 0) - goto last_chars; - } - n = n - (dest - s) - 1; - if (n == 0) - return s; - goto zero_fill; - } - - last_chars: - n &= 3; - if (n == 0) - return s; - - do - { - c = *src++; - *++dest = c; - if (--n == 0) - return s; - } - while (c != L'\0'); - - zero_fill: - do - *++dest = L'\0'; - while (--n > 0); - - return s; + size_t size = __wcsnlen (src, n); + if (size != n) + __wmemset (dest + size, L'\0', n - size); + return __wmemcpy (dest, src, size); } #ifndef WCSNCPY weak_alias (__wcsncpy, wcsncpy)