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Diffstat (limited to 'ports/sysdeps/alpha/memchr.c')
-rw-r--r--ports/sysdeps/alpha/memchr.c174
1 files changed, 0 insertions, 174 deletions
diff --git a/ports/sysdeps/alpha/memchr.c b/ports/sysdeps/alpha/memchr.c
deleted file mode 100644
index 6d80690b1d..0000000000
--- a/ports/sysdeps/alpha/memchr.c
+++ /dev/null
@@ -1,174 +0,0 @@
-/* Copyright (C) 2010-2014 Free Software Foundation, Inc.
-   This file is part of the GNU C Library.
-
-   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>
-
-typedef unsigned long word;
-
-static inline word
-ldq_u(const void *s)
-{
-  return *(const word *)((word)s & -8);
-}
-
-#define unlikely(X)	__builtin_expect ((X), 0)
-#define prefetch(X)	__builtin_prefetch ((void *)(X), 0)
-
-#define cmpbeq0(X)	__builtin_alpha_cmpbge(0, (X))
-#define find(X, Y)	cmpbeq0 ((X) ^ (Y))
-
-/* Search no more than N bytes of S for C.  */
-
-void *
-__memchr (const void *s, int xc, size_t n)
-{
-  const word *s_align;
-  word t, current, found, mask, offset;
-
-  if (unlikely (n == 0))
-    return 0;
-
-  current = ldq_u (s);
-
-  /* Replicate low byte of XC into all bytes of C.  */
-  t = xc & 0xff;			/* 0000000c */
-  t = (t << 8) | t;			/* 000000cc */
-  t = (t << 16) | t;			/* 0000cccc */
-  const word c = (t << 32) | t;		/* cccccccc */
-
-  /* Align the source, and decrement the count by the number
-     of bytes searched in the first word.  */
-  s_align = (const word *)((word)s & -8);
-  n += ((word)s & 7);
-
-  /* Deal with misalignment in the first word for the comparison.  */
-  mask = (1ul << ((word)s & 7)) - 1;
-
-  /* If the entire string fits within one word, we may need masking
-     at both the front and the back of the string.  */
-  if (unlikely (n <= 8))
-    {
-      mask |= -1ul << n;
-      goto last_quad;
-    }
-
-  found = find (current, c) & ~mask;
-  if (unlikely (found))
-    goto found_it;
-
-  s_align++;
-  n -= 8;
-
-  /* If the block is sufficiently large, align to cacheline and prefetch.  */
-  if (unlikely (n >= 256))
-    {
-      /* Prefetch 3 cache lines beyond the one we're working on.  */
-      prefetch (s_align + 8);
-      prefetch (s_align + 16);
-      prefetch (s_align + 24);
-
-      while ((word)s_align & 63)
-	{
-	  current = *s_align;
-	  found = find (current, c);
-	  if (found)
-	    goto found_it;
-	  s_align++;
-	  n -= 8;
-	}
-
-	/* Within each cacheline, advance the load for the next word
-	   before the test for the previous word is complete.  This
-	   allows us to hide the 3 cycle L1 cache load latency.  We
-	   only perform this advance load within a cacheline to prevent
-	   reading across page boundary.  */
-#define CACHELINE_LOOP				\
-	do {					\
-	  word i, next = s_align[0];		\
-	  for (i = 0; i < 7; ++i)		\
-	    {					\
-	      current = next;			\
-	      next = s_align[1];		\
-	      found = find (current, c);	\
-	      if (unlikely (found))		\
-		goto found_it;			\
-	      s_align++;			\
-	    }					\
-	  current = next;			\
-	  found = find (current, c);		\
-	  if (unlikely (found))			\
-	    goto found_it;			\
-	  s_align++;				\
-	  n -= 64;				\
-	} while (0)
-
-      /* While there's still lots more data to potentially be read,
-	 continue issuing prefetches for the 4th cacheline out.  */
-      while (n >= 256)
-	{
-	  prefetch (s_align + 24);
-	  CACHELINE_LOOP;
-	}
-
-      /* Up to 3 cache lines remaining.  Continue issuing advanced
-	 loads, but stop prefetching.  */
-      while (n >= 64)
-	CACHELINE_LOOP;
-
-      /* We may have exhausted the buffer.  */
-      if (n == 0)
-	return NULL;
-    }
-
-  /* Quadword aligned loop.  */
-  current = *s_align;
-  while (n > 8)
-    {
-      found = find (current, c);
-      if (unlikely (found))
-	goto found_it;
-      current = *++s_align;
-      n -= 8;
-    }
-
-  /* The last word may need masking at the tail of the compare.  */
-  mask = -1ul << n;
- last_quad:
-  found = find (current, c) & ~mask;
-  if (found == 0)
-    return NULL;
-
- found_it:
-#ifdef __alpha_cix__
-  offset = __builtin_alpha_cttz (found);
-#else
-  /* Extract LSB.  */
-  found &= -found;
-
-  /* Binary search for the LSB.  */
-  offset  = (found & 0x0f ? 0 : 4);
-  offset += (found & 0x33 ? 0 : 2);
-  offset += (found & 0x55 ? 0 : 1);
-#endif
-
-  return (void *)((word)s_align + offset);
-}
-
-#ifdef weak_alias
-weak_alias (__memchr, memchr)
-#endif
-libc_hidden_builtin_def (memchr)