musl - Fwd: Alignment check in strlen

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Message-ID: <CAMRJFfL3ZnFdiW9_JS2p3mpvSLp_28zwmZDu3GbmNo+jkfdqsA@mail.gmail.com>
Date: Wed, 20 Feb 2013 19:05:28 +0100
From: Jonas Wagner <jonas.wagner@...l.ch>
To: musl@...ts.openwall.com
Subject: Fwd: Alignment check in strlen

Dear all,

attached is a patch that makes the alignment check in strlen more
consistent with the one in memcpy, and hopefully faster.

In src/string/memcpy.c, I find the following:

#define ALIGN (sizeof(size_t)-1)
if (((uintptr_t)d & ALIGN) != ((uintptr_t)s & ALIGN))
  goto misaligned;

In src/string/strlen.c, a different check was used instead:

#define ALIGN (sizeof(size_t))
for (; (uintptr_t)s % ALIGN; s++) if (!*s) return s-a;

I do not think there is any particular reason for this difference.

Best,
Jonas

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