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diff --git a/share/gdb/python/gdb/function/strfns.py b/share/gdb/python/gdb/function/strfns.py
new file mode 100644
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+++ b/share/gdb/python/gdb/function/strfns.py
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+# Useful gdb string convenience functions.
+# Copyright (C) 2012-2013 Free Software Foundation, Inc.
+
+# 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 of the License, 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, see <http://www.gnu.org/licenses/>.
+
+"""$_memeq, $_strlen, $_streq, $_regex"""
+
+import gdb
+import re
+
+
+class _MemEq(gdb.Function):
+  """$_memeq - compare bytes of memory
+
+Usage:
+  $_memeq(a, b, len)
+
+Returns:
+  True if len bytes at a and b compare equally.
+"""
+  def __init__(self):
+    super(_MemEq, self).__init__("_memeq")
+
+  def invoke(self, a, b, length):
+    if length < 0:
+      raise ValueError("length must be non-negative")
+    if length == 0:
+      return True
+    # The argument(s) to vector are [low_bound,]high_bound.
+    byte_vector = gdb.lookup_type("char").vector(length - 1)
+    ptr_byte_vector = byte_vector.pointer()
+    a_ptr = a.reinterpret_cast(ptr_byte_vector)
+    b_ptr = b.reinterpret_cast(ptr_byte_vector)
+    return a_ptr.dereference() == b_ptr.dereference()
+
+
+class _StrLen(gdb.Function):
+  """$_strlen - compute string length
+
+Usage:
+  $_strlen(a)
+
+Returns:
+  Length of string a, assumed to be a string in the current language.
+"""
+  def __init__(self):
+    super(_StrLen, self).__init__("_strlen")
+
+  def invoke(self, a):
+    s = a.string()
+    return len(s)
+
+
+class _StrEq(gdb.Function):
+  """$_streq - check string equality
+
+Usage:
+  $_streq(a, b)
+
+Returns:
+  True if a and b are identical strings in the current language.
+
+Example (amd64-linux):
+  catch syscall open
+  cond $bpnum $_streq((char*) $rdi, "foo")
+"""
+  def __init__(self):
+    super(_StrEq, self).__init__("_streq")
+
+  def invoke(self, a, b):
+    return a.string() == b.string()
+
+
+class _RegEx(gdb.Function):
+  """$_regex - check if a string matches a regular expression
+
+Usage:
+  $_regex(string, regex)
+
+Returns:
+  True if string str (in the current language) matches the
+  regular expression regex.
+"""
+  def __init__(self):
+    super(_RegEx, self).__init__("_regex")
+
+  def invoke(self, string, regex):
+    s = string.string()
+    r = re.compile(regex.string())
+    return bool(r.match(s))
+
+
+# GDB will import us automagically via gdb/__init__.py.
+_MemEq()
+_StrLen()
+_StrEq()
+_RegEx()