1 files changed, 38 insertions, 8 deletions
diff --git a/string/strcspn.c b/string/strcspn.c
index 8888919639..c535dd1c3d 100644
--- a/string/strcspn.c
+++ b/string/strcspn.c
@@ -16,6 +16,7 @@
    <http://www.gnu.org/licenses/>.  */
 
 #include <string.h>
+#include <stdint.h>
 
 #undef strcspn
 
@@ -26,16 +27,45 @@
 /* Return the length of the maximum initial segment of S
    which contains no characters from REJECT.  */
 size_t
-STRCSPN (const char *s, const char *reject)
+STRCSPN (const char *str, const char *reject)
 {
-  size_t count = 0;
+  if (__glibc_unlikely (reject[0] == '\0') ||
+      __glibc_unlikely (reject[1] == '\0'))
+    return __strchrnul (str, reject [0]) - str;
 
-  while (*s != '\0')
-    if (strchr (reject, *s++) == NULL)
-      ++count;
-    else
-      return count;
+  /* Use multiple small memsets to enable inlining on most targets.  */
+  unsigned char table[256];
+  unsigned char *p = memset (table, 0, 64);
+  memset (p + 64, 0, 64);
+  memset (p + 128, 0, 64);
+  memset (p + 192, 0, 64);
 
-  return count;
+  unsigned char *s = (unsigned char*) reject;
+  unsigned char tmp;
+  do
+    p[tmp = *s++] = 1;
+  while (tmp);
+
+  s = (unsigned char*) str;
+  if (p[s[0]]) return 0;
+  if (p[s[1]]) return 1;
+  if (p[s[2]]) return 2;
+  if (p[s[3]]) return 3;
+
+  s = (unsigned char *) ((uintptr_t)(s) & ~3);
+
+  unsigned int c0, c1, c2, c3;
+  do
+    {
+      s += 4;
+      c0 = p[s[0]];
+      c1 = p[s[1]];
+      c2 = p[s[2]];
+      c3 = p[s[3]];
+    }
+  while ((c0 | c1 | c2 | c3) == 0);
+
+  size_t count = s - (unsigned char *) str;
+  return (c0 | c1) != 0 ? count - c0 + 1 : count - c2 + 3;
 }
 libc_hidden_builtin_def (strcspn)