1 /*
2 * Copyright © 2012 Intel Corporation
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining a
5 * copy of this software and associated documentation files (the "Software"),
6 * to deal in the Software without restriction, including without limitation
7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8 * and/or sell copies of the Software, and to permit persons to whom the
9 * Software is furnished to do so, subject to the following conditions:
10 *
11 * The above copyright notice and this permission notice (including the next
12 * paragraph) shall be included in all copies or substantial portions of the
13 * Software.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
21 * IN THE SOFTWARE.
22 *
23 * Authors:
24 * Eric Anholt <eric@anholt.net>
25 *
26 */
27
28 #ifndef BRW_CFG_H
29 #define BRW_CFG_H
30
31 #include "brw_ir.h"
32 #ifdef __cplusplus
33 #include "brw_ir_analysis.h"
34 #endif
35
36 struct bblock_t;
37
38 /**
39 * CFG edge types.
40 *
41 * A logical edge represents a potential control flow path of the original
42 * scalar program, while a physical edge represents a control flow path that
43 * may not have existed in the original program but was introduced during
44 * vectorization in order to implement divergent control flow of different
45 * shader invocations within the same SIMD thread.
46 *
47 * All logical edges in the CFG are considered to be physical edges but not
48 * the other way around -- I.e. the logical CFG is a subset of the physical
49 * one.
50 */
51 enum bblock_link_kind {
52 bblock_link_logical = 0,
53 bblock_link_physical
54 };
55
56 struct bblock_link {
57 #ifdef __cplusplus
58 DECLARE_RALLOC_CXX_OPERATORS(bblock_link)
59
bblock_linkbblock_link60 bblock_link(bblock_t *block, enum bblock_link_kind kind)
61 : block(block), kind(kind)
62 {
63 }
64 #endif
65
66 struct exec_node link;
67 struct bblock_t *block;
68
69 /* Type of this CFG edge. Because bblock_link_logical also implies
70 * bblock_link_physical, the proper way to test for membership of edge 'l'
71 * in CFG kind 'k' is 'l.kind <= k'.
72 */
73 enum bblock_link_kind kind;
74 };
75
76 struct backend_shader;
77 struct cfg_t;
78
79 struct bblock_t {
80 #ifdef __cplusplus
81 DECLARE_RALLOC_CXX_OPERATORS(bblock_t)
82
83 explicit bblock_t(cfg_t *cfg);
84
85 void add_successor(void *mem_ctx, bblock_t *successor,
86 enum bblock_link_kind kind);
87 bool is_predecessor_of(const bblock_t *block,
88 enum bblock_link_kind kind) const;
89 bool is_successor_of(const bblock_t *block,
90 enum bblock_link_kind kind) const;
91 bool can_combine_with(const bblock_t *that) const;
92 void combine_with(bblock_t *that);
93 void dump() const;
94
95 backend_instruction *start();
96 const backend_instruction *start() const;
97 backend_instruction *end();
98 const backend_instruction *end() const;
99
100 bblock_t *next();
101 const bblock_t *next() const;
102 bblock_t *prev();
103 const bblock_t *prev() const;
104
105 bool starts_with_control_flow() const;
106 bool ends_with_control_flow() const;
107
108 backend_instruction *first_non_control_flow_inst();
109 backend_instruction *last_non_control_flow_inst();
110 #endif
111
112 struct exec_node link;
113 struct cfg_t *cfg;
114
115 int start_ip;
116 int end_ip;
117
118 /**
119 * Change in end_ip since the last time IPs of later blocks were updated.
120 */
121 int end_ip_delta;
122
123 struct exec_list instructions;
124 struct exec_list parents;
125 struct exec_list children;
126 int num;
127 };
128
129 static inline struct backend_instruction *
bblock_start(struct bblock_t * block)130 bblock_start(struct bblock_t *block)
131 {
132 return (struct backend_instruction *)exec_list_get_head(&block->instructions);
133 }
134
135 static inline const struct backend_instruction *
bblock_start_const(const struct bblock_t * block)136 bblock_start_const(const struct bblock_t *block)
137 {
138 return (const struct backend_instruction *)exec_list_get_head_const(&block->instructions);
139 }
140
141 static inline struct backend_instruction *
bblock_end(struct bblock_t * block)142 bblock_end(struct bblock_t *block)
143 {
144 return (struct backend_instruction *)exec_list_get_tail(&block->instructions);
145 }
146
147 static inline const struct backend_instruction *
bblock_end_const(const struct bblock_t * block)148 bblock_end_const(const struct bblock_t *block)
149 {
150 return (const struct backend_instruction *)exec_list_get_tail_const(&block->instructions);
151 }
152
153 static inline struct bblock_t *
bblock_next(struct bblock_t * block)154 bblock_next(struct bblock_t *block)
155 {
156 if (exec_node_is_tail_sentinel(block->link.next))
157 return NULL;
158
159 return (struct bblock_t *)block->link.next;
160 }
161
162 static inline const struct bblock_t *
bblock_next_const(const struct bblock_t * block)163 bblock_next_const(const struct bblock_t *block)
164 {
165 if (exec_node_is_tail_sentinel(block->link.next))
166 return NULL;
167
168 return (const struct bblock_t *)block->link.next;
169 }
170
171 static inline struct bblock_t *
bblock_prev(struct bblock_t * block)172 bblock_prev(struct bblock_t *block)
173 {
174 if (exec_node_is_head_sentinel(block->link.prev))
175 return NULL;
176
177 return (struct bblock_t *)block->link.prev;
178 }
179
180 static inline const struct bblock_t *
bblock_prev_const(const struct bblock_t * block)181 bblock_prev_const(const struct bblock_t *block)
182 {
183 if (exec_node_is_head_sentinel(block->link.prev))
184 return NULL;
185
186 return (const struct bblock_t *)block->link.prev;
187 }
188
189 static inline bool
bblock_starts_with_control_flow(const struct bblock_t * block)190 bblock_starts_with_control_flow(const struct bblock_t *block)
191 {
192 enum opcode op = bblock_start_const(block)->opcode;
193 return op == BRW_OPCODE_DO || op == BRW_OPCODE_ENDIF;
194 }
195
196 static inline bool
bblock_ends_with_control_flow(const struct bblock_t * block)197 bblock_ends_with_control_flow(const struct bblock_t *block)
198 {
199 enum opcode op = bblock_end_const(block)->opcode;
200 return op == BRW_OPCODE_IF ||
201 op == BRW_OPCODE_ELSE ||
202 op == BRW_OPCODE_WHILE ||
203 op == BRW_OPCODE_BREAK ||
204 op == BRW_OPCODE_CONTINUE;
205 }
206
207 static inline struct backend_instruction *
bblock_first_non_control_flow_inst(struct bblock_t * block)208 bblock_first_non_control_flow_inst(struct bblock_t *block)
209 {
210 struct backend_instruction *inst = bblock_start(block);
211 if (bblock_starts_with_control_flow(block))
212 #ifdef __cplusplus
213 inst = (struct backend_instruction *)inst->next;
214 #else
215 inst = (struct backend_instruction *)inst->link.next;
216 #endif
217 return inst;
218 }
219
220 static inline struct backend_instruction *
bblock_last_non_control_flow_inst(struct bblock_t * block)221 bblock_last_non_control_flow_inst(struct bblock_t *block)
222 {
223 struct backend_instruction *inst = bblock_end(block);
224 if (bblock_ends_with_control_flow(block))
225 #ifdef __cplusplus
226 inst = (struct backend_instruction *)inst->prev;
227 #else
228 inst = (struct backend_instruction *)inst->link.prev;
229 #endif
230 return inst;
231 }
232
233 #ifdef __cplusplus
234 inline backend_instruction *
start()235 bblock_t::start()
236 {
237 return bblock_start(this);
238 }
239
240 inline const backend_instruction *
start()241 bblock_t::start() const
242 {
243 return bblock_start_const(this);
244 }
245
246 inline backend_instruction *
end()247 bblock_t::end()
248 {
249 return bblock_end(this);
250 }
251
252 inline const backend_instruction *
end()253 bblock_t::end() const
254 {
255 return bblock_end_const(this);
256 }
257
258 inline bblock_t *
next()259 bblock_t::next()
260 {
261 return bblock_next(this);
262 }
263
264 inline const bblock_t *
next()265 bblock_t::next() const
266 {
267 return bblock_next_const(this);
268 }
269
270 inline bblock_t *
prev()271 bblock_t::prev()
272 {
273 return bblock_prev(this);
274 }
275
276 inline const bblock_t *
prev()277 bblock_t::prev() const
278 {
279 return bblock_prev_const(this);
280 }
281
282 inline bool
starts_with_control_flow()283 bblock_t::starts_with_control_flow() const
284 {
285 return bblock_starts_with_control_flow(this);
286 }
287
288 inline bool
ends_with_control_flow()289 bblock_t::ends_with_control_flow() const
290 {
291 return bblock_ends_with_control_flow(this);
292 }
293
294 inline backend_instruction *
first_non_control_flow_inst()295 bblock_t::first_non_control_flow_inst()
296 {
297 return bblock_first_non_control_flow_inst(this);
298 }
299
300 inline backend_instruction *
last_non_control_flow_inst()301 bblock_t::last_non_control_flow_inst()
302 {
303 return bblock_last_non_control_flow_inst(this);
304 }
305 #endif
306
307 struct cfg_t {
308 #ifdef __cplusplus
309 DECLARE_RALLOC_CXX_OPERATORS(cfg_t)
310
311 cfg_t(const backend_shader *s, exec_list *instructions);
312 ~cfg_t();
313
314 void remove_block(bblock_t *block);
315
316 bblock_t *first_block();
317 const bblock_t *first_block() const;
318 bblock_t *last_block();
319 const bblock_t *last_block() const;
320
321 bblock_t *new_block();
322 void set_next_block(bblock_t **cur, bblock_t *block, int ip);
323 void make_block_array();
324
325 void dump();
326 void dump_cfg();
327
328 /**
329 * Propagate bblock_t::end_ip_delta data through the CFG.
330 */
331 inline void adjust_block_ips();
332
333 #endif
334 const struct backend_shader *s;
335 void *mem_ctx;
336
337 /** Ordered list (by ip) of basic blocks */
338 struct exec_list block_list;
339 struct bblock_t **blocks;
340 int num_blocks;
341 };
342
343 static inline struct bblock_t *
cfg_first_block(struct cfg_t * cfg)344 cfg_first_block(struct cfg_t *cfg)
345 {
346 return (struct bblock_t *)exec_list_get_head(&cfg->block_list);
347 }
348
349 static inline const struct bblock_t *
cfg_first_block_const(const struct cfg_t * cfg)350 cfg_first_block_const(const struct cfg_t *cfg)
351 {
352 return (const struct bblock_t *)exec_list_get_head_const(&cfg->block_list);
353 }
354
355 static inline struct bblock_t *
cfg_last_block(struct cfg_t * cfg)356 cfg_last_block(struct cfg_t *cfg)
357 {
358 return (struct bblock_t *)exec_list_get_tail(&cfg->block_list);
359 }
360
361 static inline const struct bblock_t *
cfg_last_block_const(const struct cfg_t * cfg)362 cfg_last_block_const(const struct cfg_t *cfg)
363 {
364 return (const struct bblock_t *)exec_list_get_tail_const(&cfg->block_list);
365 }
366
367 #ifdef __cplusplus
368 inline bblock_t *
first_block()369 cfg_t::first_block()
370 {
371 return cfg_first_block(this);
372 }
373
374 const inline bblock_t *
first_block()375 cfg_t::first_block() const
376 {
377 return cfg_first_block_const(this);
378 }
379
380 inline bblock_t *
last_block()381 cfg_t::last_block()
382 {
383 return cfg_last_block(this);
384 }
385
386 const inline bblock_t *
last_block()387 cfg_t::last_block() const
388 {
389 return cfg_last_block_const(this);
390 }
391 #endif
392
393 /* Note that this is implemented with a double for loop -- break will
394 * break from the inner loop only!
395 */
396 #define foreach_block_and_inst(__block, __type, __inst, __cfg) \
397 foreach_block (__block, __cfg) \
398 foreach_inst_in_block (__type, __inst, __block)
399
400 /* Note that this is implemented with a double for loop -- break will
401 * break from the inner loop only!
402 */
403 #define foreach_block_and_inst_safe(__block, __type, __inst, __cfg) \
404 foreach_block_safe (__block, __cfg) \
405 foreach_inst_in_block_safe (__type, __inst, __block)
406
407 #define foreach_block(__block, __cfg) \
408 foreach_list_typed (bblock_t, __block, link, &(__cfg)->block_list)
409
410 #define foreach_block_reverse(__block, __cfg) \
411 foreach_list_typed_reverse (bblock_t, __block, link, &(__cfg)->block_list)
412
413 #define foreach_block_safe(__block, __cfg) \
414 foreach_list_typed_safe (bblock_t, __block, link, &(__cfg)->block_list)
415
416 #define foreach_block_reverse_safe(__block, __cfg) \
417 foreach_list_typed_reverse_safe (bblock_t, __block, link, &(__cfg)->block_list)
418
419 #define foreach_inst_in_block(__type, __inst, __block) \
420 foreach_in_list(__type, __inst, &(__block)->instructions)
421
422 #define foreach_inst_in_block_safe(__type, __inst, __block) \
423 for (__type *__inst = (__type *)__block->instructions.head_sentinel.next, \
424 *__next = (__type *)__inst->next; \
425 __next != NULL; \
426 __inst = __next, \
427 __next = (__type *)__next->next)
428
429 #define foreach_inst_in_block_reverse(__type, __inst, __block) \
430 foreach_in_list_reverse(__type, __inst, &(__block)->instructions)
431
432 #define foreach_inst_in_block_reverse_safe(__type, __inst, __block) \
433 foreach_in_list_reverse_safe(__type, __inst, &(__block)->instructions)
434
435 #define foreach_inst_in_block_starting_from(__type, __scan_inst, __inst) \
436 for (__type *__scan_inst = (__type *)__inst->next; \
437 !__scan_inst->is_tail_sentinel(); \
438 __scan_inst = (__type *)__scan_inst->next)
439
440 #define foreach_inst_in_block_reverse_starting_from(__type, __scan_inst, __inst) \
441 for (__type *__scan_inst = (__type *)__inst->prev; \
442 !__scan_inst->is_head_sentinel(); \
443 __scan_inst = (__type *)__scan_inst->prev)
444
445 #ifdef __cplusplus
446 inline void
adjust_block_ips()447 cfg_t::adjust_block_ips()
448 {
449 int delta = 0;
450
451 foreach_block(block, this) {
452 block->start_ip += delta;
453 block->end_ip += delta;
454
455 delta += block->end_ip_delta;
456
457 block->end_ip_delta = 0;
458 }
459 }
460
461 namespace brw {
462 /**
463 * Immediate dominator tree analysis of a shader.
464 */
465 struct idom_tree {
466 idom_tree(const backend_shader *s);
467 ~idom_tree();
468
469 bool
validateidom_tree470 validate(const backend_shader *) const
471 {
472 /* FINISHME */
473 return true;
474 }
475
476 analysis_dependency_class
dependency_classidom_tree477 dependency_class() const
478 {
479 return DEPENDENCY_BLOCKS;
480 }
481
482 const bblock_t *
parentidom_tree483 parent(const bblock_t *b) const
484 {
485 assert(unsigned(b->num) < num_parents);
486 return parents[b->num];
487 }
488
489 bblock_t *
parentidom_tree490 parent(bblock_t *b) const
491 {
492 assert(unsigned(b->num) < num_parents);
493 return parents[b->num];
494 }
495
496 bblock_t *
497 intersect(bblock_t *b1, bblock_t *b2) const;
498
499 void
500 dump() const;
501
502 private:
503 unsigned num_parents;
504 bblock_t **parents;
505 };
506 }
507 #endif
508
509 #endif /* BRW_CFG_H */
510