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diff --git a/gdb/hash-table.c b/gdb/hash-table.c
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+/* A type-safe hash table template.
+   Copyright (C) 2012-2019 Free Software Foundation, Inc.
+   Contributed by Lawrence Crowl <crowl@google.com>
+
+This file is part of GCC.
+
+GCC 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.
+
+GCC 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 GCC; see the file COPYING3.  If not see
+<http://www.gnu.org/licenses/>.  */
+
+
+/* This file implements a typed hash table.
+   The implementation borrows from libiberty's hashtab.  */
+
+#include "defs.h"
+#include "gdbtypes.h"
+#include "hash-table.h"
+
+/* Table of primes and multiplicative inverses.
+
+   Note that these are not minimally reduced inverses.  Unlike when generating
+   code to divide by a constant, we want to be able to use the same algorithm
+   all the time.  All of these inverses (are implied to) have bit 32 set.
+
+   For the record, here's the function that computed the table; it's a 
+   vastly simplified version of the function of the same name from gcc.  */
+
+struct prime_ent const prime_tab[] = {
+  {          7, 0x24924925, 0x9999999b, 2 },
+  {         13, 0x3b13b13c, 0x745d1747, 3 },
+  {         31, 0x08421085, 0x1a7b9612, 4 },
+  {         61, 0x0c9714fc, 0x15b1e5f8, 5 },
+  {        127, 0x02040811, 0x0624dd30, 6 },
+  {        251, 0x05197f7e, 0x073260a5, 7 },
+  {        509, 0x01824366, 0x02864fc8, 8 },
+  {       1021, 0x00c0906d, 0x014191f7, 9 },
+  {       2039, 0x0121456f, 0x0161e69e, 10 },
+  {       4093, 0x00300902, 0x00501908, 11 },
+  {       8191, 0x00080041, 0x00180241, 12 },
+  {      16381, 0x000c0091, 0x00140191, 13 },
+  {      32749, 0x002605a5, 0x002a06e6, 14 },
+  {      65521, 0x000f00e2, 0x00110122, 15 },
+  {     131071, 0x00008001, 0x00018003, 16 },
+  {     262139, 0x00014002, 0x0001c004, 17 },
+  {     524287, 0x00002001, 0x00006001, 18 },
+  {    1048573, 0x00003001, 0x00005001, 19 },
+  {    2097143, 0x00004801, 0x00005801, 20 },
+  {    4194301, 0x00000c01, 0x00001401, 21 },
+  {    8388593, 0x00001e01, 0x00002201, 22 },
+  {   16777213, 0x00000301, 0x00000501, 23 },
+  {   33554393, 0x00001381, 0x00001481, 24 },
+  {   67108859, 0x00000141, 0x000001c1, 25 },
+  {  134217689, 0x000004e1, 0x00000521, 26 },
+  {  268435399, 0x00000391, 0x000003b1, 27 },
+  {  536870909, 0x00000019, 0x00000029, 28 },
+  { 1073741789, 0x0000008d, 0x00000095, 29 },
+  { 2147483647, 0x00000003, 0x00000007, 30 },
+  /* Avoid "decimal constant so large it is unsigned" for 4294967291.  */
+  { 0xfffffffb, 0x00000006, 0x00000008, 31 }
+};
+
+/* Limit number of comparisons when calling hash_table<>::verify.  */
+unsigned int hash_table_sanitize_eq_limit;
+
+/* The following function returns an index into the above table of the
+   nearest prime number which is greater than N, and near a power of two. */
+
+unsigned int
+hash_table_higher_prime_index (unsigned long n)
+{
+  unsigned int low = 0;
+  unsigned int high = sizeof (prime_tab) / sizeof (prime_tab[0]);
+
+  while (low != high)
+    {
+      unsigned int mid = low + (high - low) / 2;
+      if (n > prime_tab[mid].prime)
+	low = mid + 1;
+      else
+	high = mid;
+    }
+
+  /* If we've run out of primes, abort.  */
+  gdb_assert (n <= prime_tab[low].prime);
+
+  return low;
+}