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-rw-r--r--sysdeps/tile/tilepro/rawmemchr.c45
1 files changed, 45 insertions, 0 deletions
diff --git a/sysdeps/tile/tilepro/rawmemchr.c b/sysdeps/tile/tilepro/rawmemchr.c
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+++ b/sysdeps/tile/tilepro/rawmemchr.c
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+/* Copyright (C) 2011-2014 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Chris Metcalf <cmetcalf@tilera.com>, 2011.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library.  If not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <string.h>
+#include <stdint.h>
+
+void *
+__rawmemchr (const void *s, int c)
+{
+  /* Get an aligned pointer. */
+  const uintptr_t s_int = (uintptr_t) s;
+  const uint32_t *p = (const uint32_t *) (s_int & -4);
+
+  /* Create four copies of the byte for which we are looking. */
+  const uint32_t goal = 0x01010101 * (uint8_t) c;
+
+  /* Read the first word, but munge it so that bytes before the array
+     will not match goal.  Note that this shift count expression works
+     because we know shift counts are taken mod 32.  */
+  const uint32_t before_mask = (1 << (s_int << 3)) - 1;
+  uint32_t v = (*p | before_mask) ^ (goal & before_mask);
+
+  uint32_t bits;
+  while ((bits = __insn_seqb (v, goal)) == 0)
+    v = *++p;
+
+  return ((char *) p) + (__insn_ctz (bits) >> 3);
+}
+libc_hidden_def (__rawmemchr)
+weak_alias (__rawmemchr, rawmemchr)