Merge commit 'refs/top-bases/t/bigmem' into t/bigmem

1 files changed, 270 insertions, 0 deletions

diff --git a/sysdeps/tile/tilegx/strstr.c b/sysdeps/tile/tilegx/strstr.c
new file mode 100644
index 0000000000..c0cca1908a
--- /dev/null
+++ b/sysdeps/tile/tilegx/strstr.c
@@ -0,0 +1,270 @@
+/* Copyright (C) 2013-2015 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, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+/* Specification of strstr.  */
+#include <string.h>
+
+#include <stdbool.h>
+#include "string-endian.h"
+
+#define RETURN_TYPE char *
+#define AVAILABLE(h, h_l, j, n_l)			\
+  (!memchr ((h) + (h_l), '\0', (j) + (n_l) - (h_l))	\
+   && ((h_l) = (j) + (n_l)))
+#include "str-two-way.h"
+typeof(two_way_short_needle) two_way_short_needle __attribute__((unused));
+
+#undef strstr
+
+#ifndef STRSTR
+#define STRSTR strstr
+#endif
+
+#ifndef STRSTR2
+#define STRSTR2 strstr2
+#endif
+
+#ifndef STRCHR
+#define STRCHR strchr
+#endif
+
+#ifndef STRSTR_SCAN
+#define STRSTR_SCAN strstr_scan
+#endif
+
+#ifndef TOLOWER
+# define TOLOWER(Ch) (Ch)
+#endif
+
+#ifdef USE_AS_STRCASESTR
+
+static uint64_t
+vec_tolower (uint64_t cc)
+{
+  /* For Uppercases letters, add 32 to convert to lower case.  */
+  uint64_t less_than_eq_Z = __insn_v1cmpltui (cc, 'Z' + 1);
+  uint64_t less_than_A =  __insn_v1cmpltui (cc, 'A');
+  uint64_t is_upper = __insn_v1cmpne (less_than_eq_Z, less_than_A);
+  return __insn_v1add (cc,__insn_v1shli (is_upper, 5));
+}
+
+/* There is no strcasechr() defined, but needed for 1 byte case
+   of strcasestr(), so create it here.  */
+
+static char *
+strcasechr (const char *s, int c)
+{
+  int z, g;
+
+  c = tolower (c);
+
+  /* Get an aligned pointer.  */
+  const uintptr_t s_int = (uintptr_t) s;
+  const uint64_t *p = (const uint64_t *) (s_int & -8);
+
+  /* Create eight copies of the byte for which we are looking.  */
+  const uint64_t goal = copy_byte(c);
+
+  /* Read the first aligned word, but force bytes before the string to
+     match neither zero nor goal (we make sure the high bit of each byte
+     is 1, and the low 7 bits are all the opposite of the goal byte).  */
+  const uint64_t before_mask = MASK (s_int);
+  uint64_t v =
+    (vec_tolower (*p) | before_mask) ^ (goal & __insn_v1shrui (before_mask, 1));
+
+  uint64_t zero_matches, goal_matches;
+  while (1)
+    {
+      /* Look for a terminating '\0'.  */
+      zero_matches = __insn_v1cmpeqi (v, 0);
+
+      /* Look for the goal byte.  */
+      goal_matches = __insn_v1cmpeq (v, goal);
+
+      if (__builtin_expect ((zero_matches | goal_matches) != 0, 0))
+        break;
+
+      v = vec_tolower (*++p);
+    }
+
+  z = CFZ (zero_matches);
+  g = CFZ (goal_matches);
+
+  /* If we found c before '\0' we got a match. Note that if c == '\0'
+     then g == z, and we correctly return the address of the '\0'
+     rather than NULL.  */
+  return (g <= z) ? ((char *) p) + (g >> 3) : NULL;
+}
+
+# define vec_load(p) vec_tolower (*(p))
+# define STRCHR strcasechr
+# define CMP_FUNC __strncasecmp
+
+#else
+
+# define vec_load(p) (*(p))
+# define STRCHR strchr
+# define CMP_FUNC memcmp
+
+#endif
+
+
+/* Compare 2-character needle using SIMD.  */
+static char *
+STRSTR2 (const char *haystack_start, const char *needle)
+{
+  int z, g;
+
+  __insn_prefetch (haystack_start + 64);
+
+  /* Get an aligned pointer.  */
+  const uintptr_t s_int = (uintptr_t) haystack_start;
+  const uint64_t *p = (const uint64_t *) (s_int & -8);
+
+  /* Create eight copies of the first byte for which we are looking.  */
+  const uint64_t byte1 = copy_byte (TOLOWER (*needle));
+  /* Create eight copies of the second byte for which we are looking.  */
+  const uint64_t byte2 = copy_byte (TOLOWER (*(needle + 1)));
+
+  /* Read the first aligned word, but force bytes before the string to
+     match neither zero nor goal (we make sure the high bit of each byte
+     is 1, and the low 7 bits are all the opposite of the goal byte).  */
+  const uint64_t before_mask = MASK (s_int);
+  uint64_t v =
+    (vec_load (p) | before_mask) ^ (byte1 & __insn_v1shrui (before_mask, 1));
+
+  uint64_t zero_matches, goal_matches;
+  while (1)
+    {
+      /* Look for a terminating '\0'.  */
+      zero_matches = __insn_v1cmpeqi (v, 0);
+      uint64_t byte1_matches = __insn_v1cmpeq (v, byte1);
+      if (__builtin_expect (zero_matches != 0, 0))
+	{
+	  /* This is the last vector.  Don't worry about matches
+	     crossing into the next vector.  Shift the second byte
+	     back 1 byte to align it with the first byte, then and to
+	     check for both matching.  Each vector has a 1 in the LSB
+	     of the byte if there was match.  */
+	  uint64_t byte2_matches = __insn_v1cmpeq (v, byte2);
+	  goal_matches = byte1_matches & STRSHIFT (byte2_matches, 8);
+	  break;
+	}
+      else
+	{
+	  /* This is not the last vector, so load the next vector now.
+	     And compare byte2 to the 8-bytes starting 1 byte shifted from v,
+	     which goes 1-byte into the next vector.  */
+	  uint64_t v2 = vec_load (p + 1);
+	  if (byte1_matches)
+	    {
+	      /* 8-bytes starting 1 byte into v.  */
+	      v = __insn_dblalign (v, v2, (void*)1);
+	      uint64_t byte2_matches_shifted = __insn_v1cmpeq (v, byte2);
+	      goal_matches = byte1_matches & byte2_matches_shifted;
+	      if (__builtin_expect (goal_matches != 0, 0))
+		break;
+	    }
+	  __insn_prefetch (p + 4);
+	  /* Move to next vector.  */
+	  v = v2;
+	  p++;
+	}
+    }
+
+  z = CFZ (zero_matches);
+  g = CFZ (goal_matches);
+
+  /* If we found the match before '\0' we got a true match. Note that
+     if c == '\0' then g == z, and we correctly return the address of
+     the '\0' rather than NULL.  */
+  return (g <= z) ? ((char *) p) + (g >> 3) : NULL;
+}
+
+/* Scan for NEEDLE, using the first two characters as a filter.  */
+static char *
+STRSTR_SCAN (const char *haystack, const char *needle,
+	     unsigned int needle_len)
+{
+  char *match;
+  while (1)
+    {
+      match = STRSTR2 (haystack, needle);
+      if (match == NULL)
+	return NULL;
+      /* Found first two characters of needle, check for remainder.  */
+      if (CMP_FUNC (match + 2, needle + 2, needle_len - 2) == 0)
+	return match;
+      /* Move past the previous match. Could be +2 instead of +1 if
+         first two characters are different, but that tested slower.  */
+      haystack = match + 1;
+    }
+}
+
+/* Return the first occurrence of NEEDLE in HAYSTACK.  Return HAYSTACK
+   if NEEDLE is empty, otherwise NULL if NEEDLE is not found in
+   HAYSTACK.  */
+char *
+STRSTR (const char *haystack_start, const char *needle_start)
+{
+  const char *haystack = haystack_start;
+  const char *needle = needle_start;
+  __insn_prefetch (haystack);
+  size_t needle_len = strlen (needle_start); /* Length of NEEDLE.  */
+  size_t haystack_len; /* Known minimum length of HAYSTACK.  */
+
+  if (needle_len <= 2)
+    {
+      if (needle_len == 1)
+	return STRCHR (haystack_start, *needle_start);
+      if (needle_len == 0)
+	return (char *) haystack_start;
+      else
+	return STRSTR2 (haystack_start, needle_start);
+    }
+
+  /* Fail if NEEDLE is longer than HAYSTACK.  */
+  if (__strnlen (haystack, needle_len) < needle_len)
+    return NULL;
+
+  /* Perform the search.  Abstract memory is considered to be an array
+     of 'unsigned char' values, not an array of 'char' values.  See
+     ISO C 99 section 6.2.6.1.  */
+  if (needle_len < 40)
+    return STRSTR_SCAN (haystack_start, needle_start, needle_len);
+  else
+    {
+      /* Reduce the size of haystack using STRSTR2, since it has a smaller
+	 linear coefficient than the Two-Way algorithm.  */
+      haystack = STRSTR2 (haystack_start, needle_start);
+      if (haystack == NULL)
+	return NULL;
+      needle = needle_start;
+      haystack_len = (haystack > haystack_start + needle_len ? 1
+		      : needle_len + haystack_start - haystack);
+
+      return two_way_long_needle ((const unsigned char *) haystack,
+				  haystack_len,
+				  (const unsigned char *) needle, needle_len);
+    }
+}
+#ifndef USE_AS_STRCASESTR
+libc_hidden_builtin_def (STRSTR)
+#endif
+
+#undef LONG_NEEDLE_THRESHOLD