Merge GDB 7.5.1

gdb/gnulib/str-two-way.h

Index: gdb/gnulib/str-two-way.h
diff --git a/gdb/gnulib/str-two-way.h b/gdb/gnulib/str-two-way.h
deleted file mode 100644
index 7868eb81530e03445e02e2cddef1b6d301d1d134..0000000000000000000000000000000000000000
--- a/gdb/gnulib/str-two-way.h
+++ /dev/null
@@ -1,429 +0,0 @@
-/* Byte-wise substring search, using the Two-Way algorithm.
-   Copyright (C) 2008, 2009, 2010, 2011 Free Software Foundation, Inc.
-   This file is part of the GNU C Library.
-   Written by Eric Blake <ebb9@byu.net>, 2008.
-
-   This program is free software; you can redistribute it and/or modify
-   it under the terms of the GNU General Public License as published by
-   the Free Software Foundation; either version 3, or (at your option)
-   any later version.
-
-   This program 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 General Public License for more details.
-
-   You should have received a copy of the GNU General Public License along
-   with this program; if not, write to the Free Software Foundation,
-   Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */
-
-/* Before including this file, you need to include <config.h> and
-   <string.h>, and define:
-     RESULT_TYPE             A macro that expands to the return type.
-     AVAILABLE(h, h_l, j, n_l)
-                             A macro that returns nonzero if there are
-                             at least N_L bytes left starting at H[J].
-                             H is 'unsigned char *', H_L, J, and N_L
-                             are 'size_t'; H_L is an lvalue.  For
-                             NUL-terminated searches, H_L can be
-                             modified each iteration to avoid having
-                             to compute the end of H up front.
-
-  For case-insensitivity, you may optionally define:
-     CMP_FUNC(p1, p2, l)     A macro that returns 0 iff the first L
-                             characters of P1 and P2 are equal.
-     CANON_ELEMENT(c)        A macro that canonicalizes an element right after
-                             it has been fetched from one of the two strings.
-                             The argument is an 'unsigned char'; the result
-                             must be an 'unsigned char' as well.
-
-  This file undefines the macros documented above, and defines
-  LONG_NEEDLE_THRESHOLD.
-*/
-
-#include <limits.h>
-#include <stdint.h>
-
-/* We use the Two-Way string matching algorithm, which guarantees
-   linear complexity with constant space.  Additionally, for long
-   needles, we also use a bad character shift table similar to the
-   Boyer-Moore algorithm to achieve improved (potentially sub-linear)
-   performance.
-
-   See http://www-igm.univ-mlv.fr/~lecroq/string/node26.html#SECTION00260
-   and http://en.wikipedia.org/wiki/Boyer-Moore_string_search_algorithm
-*/
-
-/* Point at which computing a bad-byte shift table is likely to be
-   worthwhile.  Small needles should not compute a table, since it
-   adds (1 << CHAR_BIT) + NEEDLE_LEN computations of preparation for a
-   speedup no greater than a factor of NEEDLE_LEN.  The larger the
-   needle, the better the potential performance gain.  On the other
-   hand, on non-POSIX systems with CHAR_BIT larger than eight, the
-   memory required for the table is prohibitive.  */
-#if CHAR_BIT < 10
-# define LONG_NEEDLE_THRESHOLD 32U
-#else
-# define LONG_NEEDLE_THRESHOLD SIZE_MAX
-#endif
-
-#ifndef MAX
-# define MAX(a, b) ((a < b) ? (b) : (a))
-#endif
-
-#ifndef CANON_ELEMENT
-# define CANON_ELEMENT(c) c
-#endif
-#ifndef CMP_FUNC
-# define CMP_FUNC memcmp
-#endif
-
-/* Perform a critical factorization of NEEDLE, of length NEEDLE_LEN.
-   Return the index of the first byte in the right half, and set
-   *PERIOD to the global period of the right half.
-
-   The global period of a string is the smallest index (possibly its
-   length) at which all remaining bytes in the string are repetitions
-   of the prefix (the last repetition may be a subset of the prefix).
-
-   When NEEDLE is factored into two halves, a local period is the
-   length of the smallest word that shares a suffix with the left half
-   and shares a prefix with the right half.  All factorizations of a
-   non-empty NEEDLE have a local period of at least 1 and no greater
-   than NEEDLE_LEN.
-
-   A critical factorization has the property that the local period
-   equals the global period.  All strings have at least one critical
-   factorization with the left half smaller than the global period.
-
-   Given an ordered alphabet, a critical factorization can be computed
-   in linear time, with 2 * NEEDLE_LEN comparisons, by computing the
-   larger of two ordered maximal suffixes.  The ordered maximal
-   suffixes are determined by lexicographic comparison of
-   periodicity.  */
-static size_t
-critical_factorization (const unsigned char *needle, size_t needle_len,
-                        size_t *period)
-{
-  /* Index of last byte of left half, or SIZE_MAX.  */
-  size_t max_suffix, max_suffix_rev;
-  size_t j; /* Index into NEEDLE for current candidate suffix.  */
-  size_t k; /* Offset into current period.  */
-  size_t p; /* Intermediate period.  */
-  unsigned char a, b; /* Current comparison bytes.  */
-
-  /* Invariants:
-     0 <= j < NEEDLE_LEN - 1
-     -1 <= max_suffix{,_rev} < j (treating SIZE_MAX as if it were signed)
-     min(max_suffix, max_suffix_rev) < global period of NEEDLE
-     1 <= p <= global period of NEEDLE
-     p == global period of the substring NEEDLE[max_suffix{,_rev}+1...j]
-     1 <= k <= p
-  */
-
-  /* Perform lexicographic search.  */
-  max_suffix = SIZE_MAX;
-  j = 0;
-  k = p = 1;
-  while (j + k < needle_len)
-    {
-      a = CANON_ELEMENT (needle[j + k]);
-      b = CANON_ELEMENT (needle[max_suffix + k]);
-      if (a < b)
-        {
-          /* Suffix is smaller, period is entire prefix so far.  */
-          j += k;
-          k = 1;
-          p = j - max_suffix;
-        }
-      else if (a == b)
-        {
-          /* Advance through repetition of the current period.  */
-          if (k != p)
-            ++k;
-          else
-            {
-              j += p;
-              k = 1;
-            }
-        }
-      else /* b < a */
-        {
-          /* Suffix is larger, start over from current location.  */
-          max_suffix = j++;
-          k = p = 1;
-        }
-    }
-  *period = p;
-
-  /* Perform reverse lexicographic search.  */
-  max_suffix_rev = SIZE_MAX;
-  j = 0;
-  k = p = 1;
-  while (j + k < needle_len)
-    {
-      a = CANON_ELEMENT (needle[j + k]);
-      b = CANON_ELEMENT (needle[max_suffix_rev + k]);
-      if (b < a)
-        {
-          /* Suffix is smaller, period is entire prefix so far.  */
-          j += k;
-          k = 1;
-          p = j - max_suffix_rev;
-        }
-      else if (a == b)
-        {
-          /* Advance through repetition of the current period.  */
-          if (k != p)
-            ++k;
-          else
-            {
-              j += p;
-              k = 1;
-            }
-        }
-      else /* a < b */
-        {
-          /* Suffix is larger, start over from current location.  */
-          max_suffix_rev = j++;
-          k = p = 1;
-        }
-    }
-
-  /* Choose the longer suffix.  Return the first byte of the right
-     half, rather than the last byte of the left half.  */
-  if (max_suffix_rev + 1 < max_suffix + 1)
-    return max_suffix + 1;
-  *period = p;
-  return max_suffix_rev + 1;
-}
-
-/* Return the first location of non-empty NEEDLE within HAYSTACK, or
-   NULL.  HAYSTACK_LEN is the minimum known length of HAYSTACK.  This
-   method is optimized for NEEDLE_LEN < LONG_NEEDLE_THRESHOLD.
-   Performance is guaranteed to be linear, with an initialization cost
-   of 2 * NEEDLE_LEN comparisons.
-
-   If AVAILABLE does not modify HAYSTACK_LEN (as in memmem), then at
-   most 2 * HAYSTACK_LEN - NEEDLE_LEN comparisons occur in searching.
-   If AVAILABLE modifies HAYSTACK_LEN (as in strstr), then at most 3 *
-   HAYSTACK_LEN - NEEDLE_LEN comparisons occur in searching.  */
-static RETURN_TYPE
-two_way_short_needle (const unsigned char *haystack, size_t haystack_len,
-                      const unsigned char *needle, size_t needle_len)
-{
-  size_t i; /* Index into current byte of NEEDLE.  */
-  size_t j; /* Index into current window of HAYSTACK.  */
-  size_t period; /* The period of the right half of needle.  */
-  size_t suffix; /* The index of the right half of needle.  */
-
-  /* Factor the needle into two halves, such that the left half is
-     smaller than the global period, and the right half is
-     periodic (with a period as large as NEEDLE_LEN - suffix).  */
-  suffix = critical_factorization (needle, needle_len, &period);
-
-  /* Perform the search.  Each iteration compares the right half
-     first.  */
-  if (CMP_FUNC (needle, needle + period, suffix) == 0)
-    {
-      /* Entire needle is periodic; a mismatch can only advance by the
-         period, so use memory to avoid rescanning known occurrences
-         of the period.  */
-      size_t memory = 0;
-      j = 0;
-      while (AVAILABLE (haystack, haystack_len, j, needle_len))
-        {
-          /* Scan for matches in right half.  */
-          i = MAX (suffix, memory);
-          while (i < needle_len && (CANON_ELEMENT (needle[i])
-                                    == CANON_ELEMENT (haystack[i + j])))
-            ++i;
-          if (needle_len <= i)
-            {
-              /* Scan for matches in left half.  */
-              i = suffix - 1;
-              while (memory < i + 1 && (CANON_ELEMENT (needle[i])
-                                        == CANON_ELEMENT (haystack[i + j])))
-                --i;
-              if (i + 1 < memory + 1)
-                return (RETURN_TYPE) (haystack + j);
-              /* No match, so remember how many repetitions of period
-                 on the right half were scanned.  */
-              j += period;
-              memory = needle_len - period;
-            }
-          else
-            {
-              j += i - suffix + 1;
-              memory = 0;
-            }
-        }
-    }
-  else
-    {
-      /* The two halves of needle are distinct; no extra memory is
-         required, and any mismatch results in a maximal shift.  */
-      period = MAX (suffix, needle_len - suffix) + 1;
-      j = 0;
-      while (AVAILABLE (haystack, haystack_len, j, needle_len))
-        {
-          /* Scan for matches in right half.  */
-          i = suffix;
-          while (i < needle_len && (CANON_ELEMENT (needle[i])
-                                    == CANON_ELEMENT (haystack[i + j])))
-            ++i;
-          if (needle_len <= i)
-            {
-              /* Scan for matches in left half.  */
-              i = suffix - 1;
-              while (i != SIZE_MAX && (CANON_ELEMENT (needle[i])
-                                       == CANON_ELEMENT (haystack[i + j])))
-                --i;
-              if (i == SIZE_MAX)
-                return (RETURN_TYPE) (haystack + j);
-              j += period;
-            }
-          else
-            j += i - suffix + 1;
-        }
-    }
-  return NULL;
-}
-
-/* Return the first location of non-empty NEEDLE within HAYSTACK, or
-   NULL.  HAYSTACK_LEN is the minimum known length of HAYSTACK.  This
-   method is optimized for LONG_NEEDLE_THRESHOLD <= NEEDLE_LEN.
-   Performance is guaranteed to be linear, with an initialization cost
-   of 3 * NEEDLE_LEN + (1 << CHAR_BIT) operations.
-
-   If AVAILABLE does not modify HAYSTACK_LEN (as in memmem), then at
-   most 2 * HAYSTACK_LEN - NEEDLE_LEN comparisons occur in searching,
-   and sublinear performance O(HAYSTACK_LEN / NEEDLE_LEN) is possible.
-   If AVAILABLE modifies HAYSTACK_LEN (as in strstr), then at most 3 *
-   HAYSTACK_LEN - NEEDLE_LEN comparisons occur in searching, and
-   sublinear performance is not possible.  */
-static RETURN_TYPE
-two_way_long_needle (const unsigned char *haystack, size_t haystack_len,
-                     const unsigned char *needle, size_t needle_len)
-{
-  size_t i; /* Index into current byte of NEEDLE.  */
-  size_t j; /* Index into current window of HAYSTACK.  */
-  size_t period; /* The period of the right half of needle.  */
-  size_t suffix; /* The index of the right half of needle.  */
-  size_t shift_table[1U << CHAR_BIT]; /* See below.  */
-
-  /* Factor the needle into two halves, such that the left half is
-     smaller than the global period, and the right half is
-     periodic (with a period as large as NEEDLE_LEN - suffix).  */
-  suffix = critical_factorization (needle, needle_len, &period);
-
-  /* Populate shift_table.  For each possible byte value c,
-     shift_table[c] is the distance from the last occurrence of c to
-     the end of NEEDLE, or NEEDLE_LEN if c is absent from the NEEDLE.
-     shift_table[NEEDLE[NEEDLE_LEN - 1]] contains the only 0.  */
-  for (i = 0; i < 1U << CHAR_BIT; i++)
-    shift_table[i] = needle_len;
-  for (i = 0; i < needle_len; i++)
-    shift_table[CANON_ELEMENT (needle[i])] = needle_len - i - 1;
-
-  /* Perform the search.  Each iteration compares the right half
-     first.  */
-  if (CMP_FUNC (needle, needle + period, suffix) == 0)
-    {
-      /* Entire needle is periodic; a mismatch can only advance by the
-         period, so use memory to avoid rescanning known occurrences
-         of the period.  */
-      size_t memory = 0;
-      size_t shift;
-      j = 0;
-      while (AVAILABLE (haystack, haystack_len, j, needle_len))
-        {
-          /* Check the last byte first; if it does not match, then
-             shift to the next possible match location.  */
-          shift = shift_table[CANON_ELEMENT (haystack[j + needle_len - 1])];
-          if (0 < shift)
-            {
-              if (memory && shift < period)
-                {
-                  /* Since needle is periodic, but the last period has
-                     a byte out of place, there can be no match until
-                     after the mismatch.  */
-                  shift = needle_len - period;
-                  memory = 0;
-                }
-              j += shift;
-              continue;
-            }
-          /* Scan for matches in right half.  The last byte has
-             already been matched, by virtue of the shift table.  */
-          i = MAX (suffix, memory);
-          while (i < needle_len - 1 && (CANON_ELEMENT (needle[i])
-                                        == CANON_ELEMENT (haystack[i + j])))
-            ++i;
-          if (needle_len - 1 <= i)
-            {
-              /* Scan for matches in left half.  */
-              i = suffix - 1;
-              while (memory < i + 1 && (CANON_ELEMENT (needle[i])
-                                        == CANON_ELEMENT (haystack[i + j])))
-                --i;
-              if (i + 1 < memory + 1)
-                return (RETURN_TYPE) (haystack + j);
-              /* No match, so remember how many repetitions of period
-                 on the right half were scanned.  */
-              j += period;
-              memory = needle_len - period;
-            }
-          else
-            {
-              j += i - suffix + 1;
-              memory = 0;
-            }
-        }
-    }
-  else
-    {
-      /* The two halves of needle are distinct; no extra memory is
-         required, and any mismatch results in a maximal shift.  */
-      size_t shift;
-      period = MAX (suffix, needle_len - suffix) + 1;
-      j = 0;
-      while (AVAILABLE (haystack, haystack_len, j, needle_len))
-        {
-          /* Check the last byte first; if it does not match, then
-             shift to the next possible match location.  */
-          shift = shift_table[CANON_ELEMENT (haystack[j + needle_len - 1])];
-          if (0 < shift)
-            {
-              j += shift;
-              continue;
-            }
-          /* Scan for matches in right half.  The last byte has
-             already been matched, by virtue of the shift table.  */
-          i = suffix;
-          while (i < needle_len - 1 && (CANON_ELEMENT (needle[i])
-                                        == CANON_ELEMENT (haystack[i + j])))
-            ++i;
-          if (needle_len - 1 <= i)
-            {
-              /* Scan for matches in left half.  */
-              i = suffix - 1;
-              while (i != SIZE_MAX && (CANON_ELEMENT (needle[i])
-                                       == CANON_ELEMENT (haystack[i + j])))
-                --i;
-              if (i == SIZE_MAX)
-                return (RETURN_TYPE) (haystack + j);
-              j += period;
-            }
-          else
-            j += i - suffix + 1;
-        }
-    }
-  return NULL;
-}
-
-#undef AVAILABLE
-#undef CANON_ELEMENT
-#undef CMP_FUNC
-#undef MAX
-#undef RETURN_TYPE