aboutsummaryrefslogtreecommitdiffstats
path: root/src/gen-perf.cc
diff options
context:
space:
mode:
Diffstat (limited to 'src/gen-perf.cc')
-rw-r--r--src/gen-perf.cc359
1 files changed, 0 insertions, 359 deletions
diff --git a/src/gen-perf.cc b/src/gen-perf.cc
deleted file mode 100644
index 0b5109d4ff4d..000000000000
--- a/src/gen-perf.cc
+++ /dev/null
@@ -1,359 +0,0 @@
-/* Provides high-level routines to manipulate the keywork list
- structures the code generation output.
- Copyright (C) 1989-1998, 2000 Free Software Foundation, Inc.
- written by Douglas C. Schmidt (schmidt@ics.uci.edu)
-
-This file is part of GNU GPERF.
-
-GNU GPERF 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 1, or (at your option)
-any later version.
-
-GNU GPERF 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 GNU GPERF; see the file COPYING. If not, write to the Free
-Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111, USA. */
-
-#include <stdio.h>
-#include <stdlib.h> /* declares rand(), srand() */
-#include <time.h> /* declares time() */
-#include "options.h"
-#include "gen-perf.h"
-#include "trace.h"
-
-/* Efficiently returns the least power of two greater than or equal to X! */
-#define POW(X) ((!X)?1:(X-=1,X|=X>>1,X|=X>>2,X|=X>>4,X|=X>>8,X|=X>>16,(++X)))
-
-/* Reads input keys, possibly applies the reordering heuristic, sets the
- maximum associated value size (rounded up to the nearest power of 2),
- may initialize the associated values array, and determines the maximum
- hash table size. Note: using the random numbers is often helpful,
- though not as deterministic, of course! */
-
-Gen_Perf::Gen_Perf (void)
-{
- T (Trace t ("Gen_Perf::Gen_Perf");)
- int asso_value_max;
- int non_linked_length;
-
- Key_List::read_keys ();
- if (option[ORDER])
- reorder ();
- asso_value_max = option.get_asso_max ();
- non_linked_length = Key_List::keyword_list_length ();
- num_done = 1;
- fewest_collisions = 0;
- if (asso_value_max == 0)
- asso_value_max = non_linked_length;
- else if (asso_value_max > 0)
- asso_value_max *= non_linked_length;
- else /* if (asso_value_max < 0) */
- asso_value_max = non_linked_length / -asso_value_max;
- option.set_asso_max (POW (asso_value_max));
-
- if (option[RANDOM])
- {
- srand ((long) time (0));
-
- for (int i = 0; i < ALPHA_SIZE; i++)
- asso_values[i] = (rand () & asso_value_max - 1);
- }
- else
- {
- int asso_value = option.initial_value ();
-
- if (asso_value) /* Initialize array if user requests non-zero default. */
- for (int i = ALPHA_SIZE - 1; i >= 0; i--)
- asso_values[i] = asso_value & option.get_asso_max () - 1;
- }
- max_hash_value = Key_List::max_key_length () + option.get_asso_max () *
- option.get_max_keysig_size ();
-
- if (option[DEBUG])
- fprintf (stderr, "total non-linked keys = %d\nmaximum associated value is %d"
- "\nmaximum size of generated hash table is %d\n",
- non_linked_length, asso_value_max, max_hash_value);
-}
-
-/* Merge two disjoint hash key multisets to form the ordered disjoint union of the sets.
- (In a multiset, an element can occur multiple times.)
- Precondition: both set_1 and set_2 must be ordered. Returns the length
- of the combined set. */
-
-inline int
-Gen_Perf::compute_disjoint_union (const char *set_1, int size_1, const char *set_2, int size_2, char *set_3)
-{
- T (Trace t ("Gen_Perf::compute_disjoint_union");)
- char *base = set_3;
-
- while (size_1 > 0 && size_2 > 0)
- if (*set_1 == *set_2)
- set_1++, size_1--, set_2++, size_2--;
- else
- {
- char next;
- if (*set_1 < *set_2)
- next = *set_1++, size_1--;
- else
- next = *set_2++, size_2--;
- if (set_3 == base || next != set_3[-1])
- *set_3++ = next;
- }
-
- while (size_1 > 0)
- {
- char next;
- next = *set_1++, size_1--;
- if (set_3 == base || next != set_3[-1])
- *set_3++ = next;
- }
-
- while (size_2 > 0)
- {
- char next;
- next = *set_2++, size_2--;
- if (set_3 == base || next != set_3[-1])
- *set_3++ = next;
- }
- return set_3 - base;
-}
-
-/* Sort the UNION_SET in increasing frequency of occurrence.
- This speeds up later processing since we may assume the resulting
- set (Set_3, in this case), is ordered. Uses insertion sort, since
- the UNION_SET is typically short. */
-
-inline void
-Gen_Perf::sort_set (char *union_set, int len)
-{
- T (Trace t ("Gen_Perf::sort_set");)
- int i, j;
-
- for (i = 0, j = len - 1; i < j; i++)
- {
- int curr;
- char tmp;
-
- for (curr = i + 1, tmp = union_set[curr];
- curr > 0 && occurrences[(unsigned char)tmp] < occurrences[(unsigned char)(union_set[curr-1])];
- curr--)
- union_set[curr] = union_set[curr - 1];
-
- union_set[curr] = tmp;
- }
-}
-
-/* Generate a key set's hash value. */
-
-inline int
-Gen_Perf::hash (List_Node *key_node)
-{
- T (Trace t ("Gen_Perf::hash");)
- int sum = option[NOLENGTH] ? 0 : key_node->key_length;
-
- const char *p = key_node->char_set;
- int i = key_node->char_set_length;
- for (; i > 0; p++, i--)
- sum += asso_values[(unsigned char)(*p)];
-
- return key_node->hash_value = sum;
-}
-
-/* Find out how character value change affects successfully hashed items.
- Returns FALSE if no other hash values are affected, else returns TRUE.
- Note that because Option.Get_Asso_Max is a power of two we can guarantee
- that all legal Asso_Values are visited without repetition since
- Option.Get_Jump was forced to be an odd value! */
-
-inline int
-Gen_Perf::affects_prev (char c, List_Node *curr)
-{
- T (Trace t ("Gen_Perf::affects_prev");)
- int original_char = asso_values[(unsigned char)c];
- int total_iterations = !option[FAST]
- ? option.get_asso_max () : option.get_iterations () ? option.get_iterations () : keyword_list_length ();
-
- /* Try all legal associated values. */
-
- for (int i = total_iterations - 1; i >= 0; i--)
- {
- int collisions = 0;
-
- asso_values[(unsigned char)c] =
- (asso_values[(unsigned char)c] + (option.get_jump () ? option.get_jump () : rand ()))
- & (option.get_asso_max () - 1);
-
- /* Iteration Number array is a win, O(1) intialization time! */
- reset ();
-
- /* See how this asso_value change affects previous keywords. If
- it does better than before we'll take it! */
-
- for (List_Node *ptr = head;
- !Bool_Array::find (hash (ptr)) || ++collisions < fewest_collisions;
- ptr = ptr->next)
- if (ptr == curr)
- {
- fewest_collisions = collisions;
- if (option[DEBUG])
- fprintf (stderr, "- resolved after %d iterations", total_iterations - i);
- return 0;
- }
- }
-
- /* Restore original values, no more tries. */
- asso_values[(unsigned char)c] = original_char;
- /* If we're this far it's time to try the next character.... */
- return 1;
-}
-
-/* Change a character value, try least-used characters first. */
-
-void
-Gen_Perf::change (List_Node *prior, List_Node *curr)
-{
- T (Trace t ("Gen_Perf::change");)
- static char *union_set;
- int union_set_length;
-
- if (!union_set)
- union_set = new char [2 * option.get_max_keysig_size ()];
-
- if (option[DEBUG])
- {
- fprintf (stderr, "collision on keyword #%d, prior = \"%.*s\", curr = \"%.*s\" hash = %d\n",
- num_done,
- prior->key_length, prior->key,
- curr->key_length, curr->key,
- curr->hash_value);
- fflush (stderr);
- }
- union_set_length = compute_disjoint_union (prior->char_set, prior->char_set_length, curr->char_set, curr->char_set_length, union_set);
- sort_set (union_set, union_set_length);
-
- /* Try changing some values, if change doesn't alter other values continue normal action. */
- fewest_collisions++;
-
- const char *p = union_set;
- int i = union_set_length;
- for (; i > 0; p++, i--)
- if (!affects_prev (*p, curr))
- {
- if (option[DEBUG])
- {
- fprintf (stderr, " by changing asso_value['%c'] (char #%d) to %d\n",
- *p, p - union_set + 1, asso_values[(unsigned char)(*p)]);
- fflush (stderr);
- }
- return; /* Good, doesn't affect previous hash values, we'll take it. */
- }
-
- for (List_Node *ptr = head; ptr != curr; ptr = ptr->next)
- hash (ptr);
-
- hash (curr);
-
- if (option[DEBUG])
- {
- fprintf (stderr, "** collision not resolved after %d iterations, %d duplicates remain, continuing...\n",
- !option[FAST] ? option.get_asso_max () : option.get_iterations () ? option.get_iterations () : keyword_list_length (),
- fewest_collisions + total_duplicates);
- fflush (stderr);
- }
-}
-
-/* Does the hard stuff....
- Initializes the Iteration Number array, and attempts to find a perfect
- function that will hash all the key words without getting any
- duplications. This is made much easier since we aren't attempting
- to generate *minimum* functions, only perfect ones.
- If we can't generate a perfect function in one pass *and* the user
- hasn't enabled the DUP option, we'll inform the user to try the
- randomization option, use -D, or choose alternative key positions.
- The alternatives (e.g., back-tracking) are too time-consuming, i.e,
- exponential in the number of keys. */
-
-int
-Gen_Perf::operator() (void)
-{
- T (Trace t ("Gen_Perf::operator()");)
-#if LARGE_STACK_ARRAYS
- STORAGE_TYPE buffer[max_hash_value + 1];
-#else
- // Note: we don't use new, because that invokes a custom operator new.
- STORAGE_TYPE *buffer
- = (STORAGE_TYPE*) malloc (sizeof(STORAGE_TYPE) * (max_hash_value + 1));
- if (buffer == NULL)
- abort ();
-#endif
-
- Bool_Array::init (buffer, max_hash_value + 1);
-
- List_Node *curr;
- for (curr = head; curr; curr = curr->next)
- {
- hash (curr);
-
- for (List_Node *ptr = head; ptr != curr; ptr = ptr->next)
- if (ptr->hash_value == curr->hash_value)
- {
- change (ptr, curr);
- break;
- }
- num_done++;
- }
-
- /* Make one final check, just to make sure nothing weird happened.... */
-
- Bool_Array::reset ();
-
- for (curr = head; curr; curr = curr->next)
- if (Bool_Array::find (hash (curr)))
- if (option[DUP]) /* Keep track of this number... */
- total_duplicates++;
- else /* Yow, big problems. we're outta here! */
- {
- fprintf (stderr, "\nInternal error, duplicate value %d:\n"
- "try options -D or -r, or use new key positions.\n\n", hash (curr));
-#if !LARGE_STACK_ARRAYS
- free ((char *) buffer);
-#endif
- return 1;
- }
-
- /* Sorts the key word list by hash value, and then outputs the list.
- The generated hash table code is only output if the early stage of
- processing turned out O.K. */
-
- sort ();
- output ();
-#if !LARGE_STACK_ARRAYS
- free ((char *) buffer);
-#endif
- return 0;
-}
-
-/* Prints out some diagnostics upon completion. */
-
-Gen_Perf::~Gen_Perf (void)
-{
- T (Trace t ("Gen_Perf::~Gen_Perf");)
- if (option[DEBUG])
- {
- fprintf (stderr, "\ndumping occurrence and associated values tables\n");
-
- for (int i = 0; i < ALPHA_SIZE; i++)
- if (occurrences[i])
- fprintf (stderr, "asso_values[%c] = %6d, occurrences[%c] = %6d\n",
- i, asso_values[i], i, occurrences[i]);
-
- fprintf (stderr, "end table dumping\n");
-
- }
-}
-