From: Jakub Jelinek <jakub@redhat.com>
Date: Mon, 18 Oct 2004 10:00:48 +0000 (+0000)
Subject: 	* sysdeps/generic/strcpy_chk.c (__strcpy_chk): Speed up by checking
X-Git-Tag: cvs/fedora-glibc-2_3_3-69~2
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=3c7dae119e405a26bc23c07820d76bab0fdb0af0;p=thirdparty%2Fglibc.git

	* sysdeps/generic/strcpy_chk.c (__strcpy_chk): Speed up by checking
	destlen only every 4 bytes.
---

diff --git a/ChangeLog b/ChangeLog
index 1e5ff7d9817..a282a288dba 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2004-10-18  Jakub Jelinek  <jakub@redhat.com>
+
+	* sysdeps/generic/strcpy_chk.c (__strcpy_chk): Speed up by checking
+	destlen only every 4 bytes.
+
 2004-10-06  Maciej W. Rozycki  <macro@mips.com>
 
 	* sysdeps/unix/sysv/linux/mips/mips32/sysdep.h
diff --git a/sysdeps/generic/strcpy_chk.c b/sysdeps/generic/strcpy_chk.c
index 5c1ae44cd07..a4d909fedac 100644
--- a/sysdeps/generic/strcpy_chk.c
+++ b/sysdeps/generic/strcpy_chk.c
@@ -31,14 +31,36 @@ __strcpy_chk (dest, src, destlen)
 {
   reg_char c;
   char *s = (char *) src;
-  const ptrdiff_t off = dest - s - 1;
+  const ptrdiff_t off = dest - s;
+
+  while (__builtin_expect (destlen >= 4, 0))
+    {
+      c = s[0];
+      s[off] = c;
+      if (c == '\0')
+        return dest;
+      c = s[1];
+      s[off + 1] = c;
+      if (c == '\0')
+        return dest;
+      c = s[2];
+      s[off + 2] = c;
+      if (c == '\0')
+        return dest;
+      c = s[3];
+      s[off + 3] = c;
+      if (c == '\0')
+        return dest;
+      destlen -= 4;
+      s += 4;
+    }
 
   do
     {
       if (__builtin_expect (destlen-- == 0, 0))
-	__chk_fail ();
-      c = *s++;
-      s[off] = c;
+        __chk_fail ();
+      c = *s;
+      *(s++ + off) = c;
     }
   while (c != '\0');