Mercurial > hg > xemacs-beta
annotate src/xgccache.c @ 4964:1f509f82c8c9
fix compile error
-------------------- ChangeLog entries follow: --------------------
src/ChangeLog addition:
2010-02-01 Ben Wing <ben@xemacs.org>
* alloc.c (common_init_alloc_early):
Fix compiler breakage.
author | Ben Wing <ben@xemacs.org> |
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date | Mon, 01 Feb 2010 13:35:15 -0600 |
parents | b3ce27ca7647 |
children |
rev | line source |
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2587 | 1 /* Efficient caching of X GCs (graphics contexts). |
2 Copyright (C) 1993 Free Software Foundation, Inc. | |
3 Copyright (C) 1994, 1995 Board of Trustees, University of Illinois. | |
4 | |
5 This file is part of XEmacs. | |
6 | |
7 XEmacs is free software; you can redistribute it and/or modify it | |
8 under the terms of the GNU General Public License as published by the | |
9 Free Software Foundation; either version 2, or (at your option) any | |
10 later version. | |
11 | |
12 XEmacs is distributed in the hope that it will be useful, but WITHOUT | |
13 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
15 for more details. | |
16 | |
17 You should have received a copy of the GNU General Public License | |
18 along with XEmacs; see the file COPYING. If not, write to | |
19 the Free Software Foundation, Inc., 59 Temple Place - Suite 330, | |
20 Boston, MA 02111-1307, USA. */ | |
21 | |
22 /* Synched up with: Not in FSF. */ | |
23 | |
24 /* Emacs uses a lot of different display attributes; for example, assume | |
25 that only four fonts are in use (normal, bold, italic, and bold-italic). | |
26 Then assume that one stipple or background is used for text selections, | |
27 and another is used for highlighting mousable regions. That makes 16 | |
28 GCs already. Add in the fact that another GC may be needed to display | |
29 the text cursor in any of those regions, and you've got 32. Add in | |
30 more fonts, and it keeps increasing exponentially. | |
31 | |
32 We used to keep these GCs in a cache of merged (fully qualified) faces. | |
33 However, a lot of other code in xterm.c used XChangeGC of existing GCs, | |
34 which is kind of slow and kind of random. Also, managing the face cache | |
35 was tricky because it was hard to know when a face was no longer visible | |
36 on the frame -- we had to mark all frames as garbaged whenever a face | |
37 was changed, which caused an unpleasant amount of flicker (since faces are | |
38 created/destroyed (= changed) whenever a frame is created/destroyed. | |
39 | |
40 So this code maintains a cache at the GC level instead of at the face | |
41 level. There is an upper limit on the size of the cache, after which we | |
42 will stop creating GCs and start reusing them (reusing the least-recently- | |
43 used ones first). So if faces get changed, their GCs will eventually be | |
44 recycled. Also more sharing of GCs is possible. | |
45 | |
46 This code uses hash tables. It could be that, if the cache size is small | |
47 enough, a linear search might be faster; but I doubt it, since we need | |
48 `equal' comparisons, not `eq', and I expect that the optimal cache size | |
49 will be ~100. | |
50 | |
51 Written by jwz, 14 jun 93 | |
52 */ | |
53 | |
54 #include <config.h> | |
4908
b3ce27ca7647
various fixes related to gtk, redisplay-xlike-inc.c
Ben Wing <ben@xemacs.org>
parents:
3243
diff
changeset
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55 #include "lisp.h" |
b3ce27ca7647
various fixes related to gtk, redisplay-xlike-inc.c
Ben Wing <ben@xemacs.org>
parents:
3243
diff
changeset
|
56 #include "hash.h" |
b3ce27ca7647
various fixes related to gtk, redisplay-xlike-inc.c
Ben Wing <ben@xemacs.org>
parents:
3243
diff
changeset
|
57 |
2587 | 58 #include "xgccache.h" |
59 | |
60 #define GC_CACHE_SIZE 100 | |
61 | |
62 #define GCCACHE_HASH | |
63 | |
64 struct gcv_and_mask { | |
65 XGCValues gcv; | |
66 unsigned long mask; | |
67 }; | |
68 | |
69 struct gc_cache_cell { | |
70 GC gc; | |
71 struct gcv_and_mask gcvm; | |
72 struct gc_cache_cell *prev, *next; | |
73 }; | |
74 | |
75 struct gc_cache { | |
76 Display *dpy; /* used only as arg to XCreateGC/XFreeGC */ | |
77 Window window; /* used only as arg to XCreateGC */ | |
78 int size; | |
79 struct gc_cache_cell *head; | |
80 struct gc_cache_cell *tail; | |
81 #ifdef GCCACHE_HASH | |
82 struct hash_table *table; | |
83 #endif | |
84 | |
85 int create_count; | |
86 int delete_count; | |
87 }; | |
88 | |
89 #ifdef GCCACHE_HASH | |
90 static Hashcode | |
91 gc_cache_hash (const void *arg) | |
92 { | |
93 const struct gcv_and_mask *gcvm = (const struct gcv_and_mask *) arg; | |
94 unsigned long *longs = (unsigned long *) &gcvm->gcv; | |
95 Hashcode hash = gcvm->mask; | |
96 int i; | |
97 /* This could look at the mask and only use the used slots in the | |
98 hash code. That would win in that we wouldn't have to initialize | |
99 every slot of the gcv when calling gc_cache_lookup. But we need | |
100 the hash function to be as fast as possible; some timings should | |
101 be done. */ | |
102 for (i = 0; i < (int) (sizeof (XGCValues) / sizeof (unsigned long)); i++) | |
103 hash = (hash << 1) ^ *longs++; | |
104 return hash; | |
105 } | |
106 | |
107 #endif /* GCCACHE_HASH */ | |
108 | |
109 static int | |
110 gc_cache_eql (const void *arg1, const void *arg2) | |
111 { | |
112 /* See comment in gc_cache_hash */ | |
113 return !memcmp (arg1, arg2, sizeof (struct gcv_and_mask)); | |
114 } | |
115 | |
116 struct gc_cache * | |
117 make_gc_cache (Display *dpy, Window window) | |
118 { | |
119 struct gc_cache *cache = xnew (struct gc_cache); | |
120 cache->dpy = dpy; | |
121 cache->window = window; | |
122 cache->size = 0; | |
123 cache->head = cache->tail = 0; | |
124 cache->create_count = cache->delete_count = 0; | |
125 #ifdef GCCACHE_HASH | |
126 cache->table = | |
127 make_general_hash_table (GC_CACHE_SIZE, gc_cache_hash, gc_cache_eql); | |
128 #endif | |
129 return cache; | |
130 } | |
131 | |
132 void | |
133 free_gc_cache (struct gc_cache *cache) | |
134 { | |
135 struct gc_cache_cell *rest, *next; | |
136 rest = cache->head; | |
137 while (rest) | |
138 { | |
139 XFreeGC (cache->dpy, rest->gc); | |
140 next = rest->next; | |
141 xfree (rest, struct gc_cache_cell *); | |
142 rest = next; | |
143 } | |
144 #ifdef GCCACHE_HASH | |
145 free_hash_table (cache->table); | |
146 #endif | |
147 xfree (cache, struct gc_cache *); | |
148 } | |
149 | |
150 GC | |
151 gc_cache_lookup (struct gc_cache *cache, XGCValues *gcv, unsigned long mask) | |
152 { | |
153 struct gc_cache_cell *cell, *next, *prev; | |
154 struct gcv_and_mask gcvm; | |
155 | |
3094 | 156 #ifdef DEBUG_XEMACS |
157 (void) describe_gc_cache (cache, DGCCFLAG_DISABLE); | |
158 #endif | |
159 | |
2587 | 160 if ((!!cache->head) != (!!cache->tail)) ABORT (); |
161 if (cache->head && (cache->head->prev || cache->tail->next)) ABORT (); | |
162 | |
163 gcvm.mask = mask; | |
164 gcvm.gcv = *gcv; /* this copies... */ | |
165 | |
166 #ifdef GCCACHE_HASH | |
167 | |
168 /* The intermediate cast fools gcc into not outputting strict-aliasing | |
169 complaints */ | |
170 if (gethash (&gcvm, cache->table, (const void **) (void *) &cell)) | |
171 | |
172 #else /* !GCCACHE_HASH */ | |
173 | |
174 cell = cache->tail; /* start at the end (most recently used) */ | |
175 while (cell) | |
176 { | |
177 if (gc_cache_eql (&gcvm, &cell->gcvm)) | |
178 break; | |
179 else | |
180 cell = cell->prev; | |
181 } | |
182 | |
183 /* #### This whole file needs some serious overhauling. */ | |
184 if (!(mask | GCTile) && cell->gc->values.tile) | |
185 cell = 0; | |
186 else if (!(mask | GCStipple) && cell->gc->values.stipple) | |
187 cell = 0; | |
188 | |
189 if (cell) | |
190 | |
191 #endif /* !GCCACHE_HASH */ | |
192 | |
193 { | |
194 /* Found a cell. Move this cell to the end of the list, so that it | |
195 will be less likely to be collected than a cell that was accessed | |
196 less recently. | |
197 */ | |
3094 | 198 #if 0 |
199 debug_out ("Returning cached GC: %08lx\n", XE_GCONTEXT(cell)); | |
200 #endif | |
2587 | 201 if (cell == cache->tail) |
202 return cell->gc; | |
203 | |
204 next = cell->next; | |
205 prev = cell->prev; | |
206 if (prev) prev->next = next; | |
207 if (next) next->prev = prev; | |
208 if (cache->head == cell) cache->head = next; | |
209 cell->next = 0; | |
210 cell->prev = cache->tail; | |
211 cache->tail->next = cell; | |
212 cache->tail = cell; | |
213 if (cache->head == cell) ABORT (); | |
214 if (cell->next) ABORT (); | |
215 if (cache->head->prev) ABORT (); | |
216 if (cache->tail->next) ABORT (); | |
217 return cell->gc; | |
218 } | |
219 | |
220 /* else, cache miss. */ | |
221 | |
222 if (cache->size == GC_CACHE_SIZE) | |
223 /* Reuse the first cell on the list (least-recently-used). | |
224 Remove it from the list, and unhash it from the table. | |
225 */ | |
226 { | |
227 cell = cache->head; | |
228 cache->head = cell->next; | |
229 cache->head->prev = 0; | |
230 if (cache->tail == cell) cache->tail = 0; /* only one */ | |
3243 | 231 #if 0 |
3094 | 232 debug_out ("Cache full, freeing GC: %08lx\n ", XE_GCONTEXT(cell)); |
3243 | 233 #endif |
2587 | 234 XFreeGC (cache->dpy, cell->gc); |
235 cache->delete_count++; | |
236 #ifdef GCCACHE_HASH | |
237 remhash (&cell->gcvm, cache->table); | |
238 #endif | |
239 } | |
240 else if (cache->size > GC_CACHE_SIZE) | |
241 ABORT (); | |
242 else | |
243 { | |
244 /* Allocate a new cell (don't put it in the list or table yet). */ | |
245 cell = xnew (struct gc_cache_cell); | |
246 cache->size++; | |
247 } | |
248 | |
249 /* Now we've got a cell (new or reused). Fill it in. */ | |
250 memcpy (&cell->gcvm.gcv, gcv, sizeof (XGCValues)); | |
251 cell->gcvm.mask = mask; | |
252 | |
253 /* Put the cell on the end of the list. */ | |
254 cell->next = 0; | |
255 cell->prev = cache->tail; | |
256 if (cache->tail) cache->tail->next = cell; | |
257 cache->tail = cell; | |
258 if (! cache->head) cache->head = cell; | |
259 | |
260 cache->create_count++; | |
261 #ifdef GCCACHE_HASH | |
262 /* Hash it in the table */ | |
263 puthash (&cell->gcvm, cell, cache->table); | |
264 #endif | |
265 | |
266 /* Now make and return the GC. */ | |
267 cell->gc = XCreateGC (cache->dpy, cache->window, mask, gcv); | |
268 | |
269 /* debug */ | |
270 assert (cell->gc == gc_cache_lookup (cache, gcv, mask)); | |
271 | |
3094 | 272 #if 0 |
273 debug_out ("Returning new GC: %08lx\n ", XE_GCONTEXT(cell)); | |
274 #endif | |
2587 | 275 return cell->gc; |
276 } | |
277 | |
278 | |
279 #ifdef DEBUG_XEMACS | |
280 | |
3094 | 281 /* FLAGS |
282 The flags argument is a bitwise or of any of the following: | |
283 | |
284 DGCCFLAG_SUMMARY Summary statistics for cache | |
285 DGCCFLAG_LIST_CELLS If summary is being printed, print cell IDs too. | |
286 DGCCFLAG_CELL_DETAILS If cell IDs are being printed, additionally | |
287 print the internal fields used and values. | |
288 | |
289 DGCCFLAG_DEFAULT A predefined combination giving whatever the | |
290 maintainers are currently interested in seeing. | |
291 */ | |
2587 | 292 void |
3094 | 293 describe_gc_cache (struct gc_cache *cache, int flags) |
2587 | 294 { |
295 int count = 0; | |
296 struct gc_cache_cell *cell = cache->head; | |
3094 | 297 |
298 if (! flags & DGCCFLAG_SUMMARY) return; | |
299 | |
2587 | 300 stderr_out ("\nsize: %d", cache->size); |
301 stderr_out ("\ncreated: %d", cache->create_count); | |
302 stderr_out ("\ndeleted: %d", cache->delete_count); | |
303 | |
3094 | 304 if (flags & DGCCFLAG_LIST_CELLS) |
305 while (cell) | |
306 { | |
307 struct gc_cache_cell *cell2; | |
308 int i = 0; | |
309 stderr_out ("\n%d:\t0x%lx GC: 0x%08lx hash: 0x%08lx\n", | |
310 count, (long) cell, (long) XE_GCONTEXT(cell), | |
311 gc_cache_hash (&cell->gcvm)); | |
312 | |
313 for (cell2 = cache->head; cell2; cell2 = cell2->next, i++) | |
314 if (count != i && | |
315 gc_cache_hash (&cell->gcvm) == gc_cache_hash (&cell2->gcvm)) | |
316 stderr_out ("\tHASH COLLISION with cell %d\n", i); | |
317 stderr_out ("\tmask: %8lx\n", cell->gcvm.mask); | |
318 | |
319 if (flags & DGCCFLAG_CELL_DETAILS) | |
320 { | |
2587 | 321 #define FROB(field) do { \ |
322 if ((int)cell->gcvm.gcv.field != (~0)) \ | |
323 stderr_out ("\t%-12s%8x\n", #field ":", (int)cell->gcvm.gcv.field); \ | |
324 } while (0) | |
3094 | 325 FROB (function); |
326 FROB (plane_mask); | |
327 FROB (foreground); | |
328 FROB (background); | |
329 FROB (line_width); | |
330 FROB (line_style); | |
331 FROB (cap_style); | |
332 FROB (join_style); | |
333 FROB (fill_style); | |
334 FROB (fill_rule); | |
335 FROB (arc_mode); | |
336 FROB (tile); | |
337 FROB (stipple); | |
338 FROB (ts_x_origin); | |
339 FROB (ts_y_origin); | |
340 FROB (font); | |
341 FROB (subwindow_mode); | |
342 FROB (graphics_exposures); | |
343 FROB (clip_x_origin); | |
344 FROB (clip_y_origin); | |
345 FROB (clip_mask); | |
346 FROB (dash_offset); | |
2587 | 347 #undef FROB |
3094 | 348 } |
2587 | 349 |
3094 | 350 count++; |
351 if (cell->next && cell == cache->tail) | |
352 stderr_out ("\nERROR! tail is here!\n\n"); | |
353 else if (!cell->next && cell != cache->tail) | |
354 stderr_out ("\nERROR! tail is not at the end\n\n"); | |
355 cell = cell->next; | |
356 } /* while (cell) */ | |
357 | |
2587 | 358 if (count != cache->size) |
359 stderr_out ("\nERROR! count should be %d\n\n", cache->size); | |
360 } | |
361 | |
362 #endif /* DEBUG_XEMACS */ |