From ddf21ec79f25410bed8ab25de5a7d3003a8d03b8 Mon Sep 17 00:00:00 2001 From: Adhemerval Zanella Date: Tue, 5 Feb 2019 18:43:18 -0200 Subject: wcsmbs: optimize wcsncat This patch rewrites wcsncat using wcslen, wcsnlen, and wmemcpy. This is similar to the optimization done on strncat by 3eb38795db and e80514b5a8. Checked on x86_64-linux-gnu. * wcsmbs/wcsncat.c (wcsncat): Rewrite using wcslen, wcsnlen, and wmemcpy. --- wcsmbs/wcsncat.c | 53 +++++++---------------------------------------------- 1 file changed, 7 insertions(+), 46 deletions(-) (limited to 'wcsmbs') diff --git a/wcsmbs/wcsncat.c b/wcsmbs/wcsncat.c index 65e9b22..cb6fe71 100644 --- a/wcsmbs/wcsncat.c +++ b/wcsmbs/wcsncat.c @@ -26,54 +26,15 @@ wchar_t * WCSNCAT (wchar_t *dest, const wchar_t *src, size_t n) { - wchar_t c; - wchar_t * const s = dest; + wchar_t *ret = dest; - /* Find the end of DEST. */ - do - c = *dest++; - while (c != L'\0'); + /* Find the end of dest. */ + dest += __wcslen (dest); - /* Make DEST point before next character, so we can increment - it while memory is read (wins on pipelined cpus). */ - dest -= 2; + size_t ds = __wcsnlen (src, n); - if (n >= 4) - { - size_t n4 = n >> 2; - do - { - c = *src++; - *++dest = c; - if (c == L'\0') - return s; - c = *src++; - *++dest = c; - if (c == L'\0') - return s; - c = *src++; - *++dest = c; - if (c == L'\0') - return s; - c = *src++; - *++dest = c; - if (c == L'\0') - return s; - } while (--n4 > 0); - n &= 3; - } + dest[ds] = L'\0'; + __wmemcpy (dest, src, ds); - while (n > 0) - { - c = *src++; - *++dest = c; - if (c == L'\0') - return s; - n--; - } - - if (c != L'\0') - *++dest = L'\0'; - - return s; + return ret; } -- cgit v1.1